WO1996004346A1 - Acrylic syrup curable to a crosslinked viscoelastomeric material - Google Patents

Acrylic syrup curable to a crosslinked viscoelastomeric material Download PDF

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Publication number
WO1996004346A1
WO1996004346A1 PCT/US1995/009601 US9509601W WO9604346A1 WO 1996004346 A1 WO1996004346 A1 WO 1996004346A1 US 9509601 W US9509601 W US 9509601W WO 9604346 A1 WO9604346 A1 WO 9604346A1
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WO
WIPO (PCT)
Prior art keywords
group
radiation
syrup
unsaturated monomer
sensitive
Prior art date
Application number
PCT/US1995/009601
Other languages
French (fr)
Inventor
Greggory S. Bennett
Gaddam N. Babu
Kejian Chen
Louis E. Winslow
George F. Vesley
Patrick G. Zimmerman
Original Assignee
Minnesota Mining And Manufacturing Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Minnesota Mining And Manufacturing Company filed Critical Minnesota Mining And Manufacturing Company
Priority to JP50665496A priority Critical patent/JP3548933B2/en
Priority to DE69515310T priority patent/DE69515310T2/en
Priority to EP95928204A priority patent/EP0772655B1/en
Priority to KR1019970700535A priority patent/KR970704849A/en
Priority to US08/505,350 priority patent/US5902836A/en
Publication of WO1996004346A1 publication Critical patent/WO1996004346A1/en

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    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03FPHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004Photosensitive materials
    • G03F7/027Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00Processes of polymerisation
    • C08F2/46Polymerisation initiated by wave energy or particle radiation
    • C08F2/48Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00Processes of polymerisation
    • C08F2/46Polymerisation initiated by wave energy or particle radiation
    • C08F2/48Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light
    • C08F2/50Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light with sensitising agents
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F291/00Macromolecular compounds obtained by polymerising monomers on to macromolecular compounds according to more than one of the groups C08F251/00 - C08F289/00
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D4/00Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16
    • C09D4/06Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J4/00Adhesives based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; adhesives, based on monomers of macromolecular compounds of groups C09J183/00 - C09J183/16
    • C09J4/06Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09J159/00 - C09J187/00
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S522/00Synthetic resins or natural rubbers -- part of the class 520 series
    • Y10S522/904Monomer or polymer contains initiating group
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S522/00Synthetic resins or natural rubbers -- part of the class 520 series
    • Y10S522/904Monomer or polymer contains initiating group
    • Y10S522/905Benzophenone group

Definitions

  • This invention describes a viscoelastomeric material with high shear at ambient and elevated temperatures prepared from a blend of ethylenically unsaturated monomers. A process for making this material is also described.
  • PSAs Pressure sensitive adhesives made by photopolymerizing an alkyl acrylate and a polar copolymerizable monomer are known in the art. See, e.g., U.S. Patent Nos. RE 24,906; 4,181,755; 4,364,972; and 4,243,500.
  • Acrylic-based PSAs exhibit good adherence to high energy (i.e., polar) substrates such as metal and painted steel surfaces but generally exhibit lower adhesion to low energy (i.e., nonpolar) substrates such as polyethylene and polypropylene.
  • Solvent-processed acrylic PSA compositions can be crosslinked by adding a polyfunctional crosslinking agent that reacts with a reactive group present in the polymer. See, e.g., Japanese Kokoku 58[1983]-046236 in which is described a solvent-processed crosslinked acrylic PSA with excellent cohesion that is the reaction product of (a) a polyisocyanate, prepared by reacting (1) an acrylic copolymer having a molecular weight between 1,000 and 30,000 and from 1.7 to 5.0 functional groups that can react with an isocyanate group with (2) a diisocyanate, so that the ratio of isocyanate groups per coreactive functional group is about 2: 1, and (b) an adherent copolymer comprising functional groups that can react with an isocyanate group.
  • a polyisocyanate prepared by reacting (1) an acrylic copolymer having a molecular weight between 1,000 and 30,000 and from 1.7 to 5.0 functional groups that can react with an isocyanate group with (2) a diis
  • the cohesive strength of an acrylic PSA can be increased without unduly affecting its compliance by utilizing a photoactive crosslinking agent in conjunction with a photoinitiator. See, e.g., U.S. Patent Nos. 4,181,752;
  • Useful photoactive crosslinking agents include various aldehydes, quinones, and particularly certain chromophore- substituted halomethyl-s-triazines (because they provide desirably shortened reaction times and somewhat greater tolerance to oxygen over the non- halomethyl-containing agents), although their use can result in evolution of HC1 during polymerization.
  • An ultraviolet (UV) radiation-curable composition that includes 20 to 99% (by wt.) of a copolymer of ethylenically unsaturated monomers, 1 to 80% (by wt.) ethylenically unsaturated monomers, and 0 to 20% (by wt.) of one or more polyethylenically unsaturated compounds is described in U.S. Patent No. 5,180,756.
  • Copolymerizable photoinitiators such as 2-[4-(2-hydroxy-2,2-dimethyl-l- oxopropyl)phenoxy]ethyl 2-propenoate and their use in the polymerization of ethylenically unsaturated compounds is disclosed in U.S. Patent No. 4,922,004.
  • Japanese Kokai 2[1990]-248482 describes a photocurable PSA obtained by reacting (a) 30 to 50 parts by weight (pbw) of a copolymer of an acrylic acid alkyl ester, a copolymerizable ethylenically unsaturated monomer having a polar group, and a copolymerizable monomer with a photosensitizing group (such as 2- acryloyloxybenzophenone or 1 -acryloyloxy-2-[4-(4-chlorobenzoyl)benzoyl- oxy]ethane); (b) 40 to 60 pbw of an aryloxy acrylic monomer such as phenoxyethyl acrylate or nonylphenoxyethyl acrylate; and (c) a tackifying resin.
  • the composition is cured using a total dose of energy of 300 to 800 mJ/cm 2 from a high pressure mercury lamp. Such high intensity ultraviolet radiation is likely to produce an adhesive
  • DE 42 03 183 Cl discloses a method for producing PSA layers comprising the steps of thickening a monomer mixture that includes a photoinitiator with a separately made, solvent-free saturated UV-reactive polyacrylate; coating the thickened mixture onto a substrate; and irradiating the coated substrate.
  • the separately made polymer comprises side chains that, when irradiated, participate in crosslinking reactions.
  • the sole example involves the addition of a commercially available polymer having a molecular weight of about 200,000 to a monomer mixture that is then polymerized.
  • PSAs prepared by actinically irradiating acrylic monomers can be enhanced by the addition of polyacrylic crosslinking agents. See, e.g., U.S. Patent No. 4,379,201.
  • PSAs involve networks and are sensitive to processing conditions.
  • a composition that can be radiation cured to provide thick, high molecular weight PSA compositions with outstanding properties has not been previously described.
  • the present invention provides a syrup, preferably a syrup of a coatable viscosity, curable to a crosslinked viscoelastomeric material comprising: a) about 85 to 99.9 weight percent, preferably about 90 to 99.9 weight percent, of a solvent monomer mixture comprising 95 to 100 pbw, preferably 97 to 100 pbw, of at least one free radically-polymerizable ethylenically unsaturated monomer and 0 to 5 pbw, preferably 0 to 3 pbw, of an ethylenically unsaturated monomer comprising a radiation-sensitive ⁇ -cleaving group; b) about 0.1 to 15 weight percent, preferably about 0.1 to 10 weight percent, of a solute polymer, preferably a polymer having a molecular weight of at least 500,000, comprising about 95 to 100 weight percent mer units derived from one or more free radically-polymerizable eth
  • the present invention provides a process for making a crosslinked viscoelastomeric material comprising the steps: a) providing a composition comprising a solvent monomer mixture comprising at least one free radically-polymerizable ethylenically unsaturated monomer and 0 to 5 pbw, preferably 0 to 3 pbw, of an ethylenically unsaturated monomer comprising a radiation-sensitive ⁇ -cleaving group and 0 to 3 pbw, preferably 0.001 to 0.5 pbw, of a saturated energy-activated initiator of polymerization, preferably a saturated radiation-activated initiator of polymerization, with the proviso that the amount of saturated initiator must be greater than zero when the amount of ethylenically unsaturated monomer comprising a radiation-sensitive ⁇ -cleaving group is zero; b) exposing the composition to energy, preferably radiative energy, so as to
  • the viscoelastomeric material produced from the above syrup is also described.
  • the syrup optionally can be coated on a substrate prior to being irradiated, and such articles are also described.
  • the coatable syrup of the present invention is polymerizable to a viscoelastomeric material that can be crosslinked directly.
  • the viscoelastomeric material is preferably a PSA having high shear at both ambient and elevated
  • This syrup comprises a solute polymer in a solvent monomer mixture.
  • the polymer preferably has a very high molecular weight, preferably at least 500,000, more preferably at least 750,000, even more preferably at least 1,000,000, most preferably at least 1,500,000.
  • One or both of the polymer and monomer contains at least one radiation-sensitive ⁇ -cleaving group that, upon exposure to UV radiation, is activated to enable curing.
  • the cured product is a viscoelastomeric material.
  • the polymer of the syrup of the present invention contains side chains that comprise radiation-sensitive ⁇ -cleaving groups activatable by UV radiation, free radicals are formed that allow for growth of the side chain by addition of ethylenically unsaturated monomer(s). These growing side chains become entangled with other such side chains, or react with other such side chains, to produce a crosslinked viscoelastomeric material.
  • the polymer does not include radiation-sensitive ⁇ -cleaving group-containing side chains, the monomer mixture contains enough ethylenically unsaturated monomer comprising a radiation-sensitive ⁇ -cleaving group to form, upon exposure to UV radiation, a polymer that includes radiation-sensitive ⁇ -cleaving groups in side chains.
  • the original polymer chains become entangled with the newly formed polymer chains to form a crosslinked network.
  • some polymer that includes side chains comprising the aforementioned radiation- sensitive ⁇ -cleaving groups or some monomer that contains a radiation-sensitive ⁇ -cleaving group must be added to the syrup prior to formation of the viscoelastomeric material therefrom (i.e., polymerization of the monomer(s) of the monomer mixture).
  • the solute polymer is prepared in situ, i.e., directly from the solvent monomer mixture.
  • Viscoelastomeric materials produced from the syrup of the present invention can be used as PSAs, vibration damping materials, transfer adhesives, structural adhesives, protective coatings, and the like.
  • the syrup of the present invention can have a coatable viscosity and can therefore be applied to a substrate prior to curing, thus allowing for the simple production of articles comprising one or more layers of the aforementioned viscoelastomeric material.
  • group or “compound” or “monomer” or “polymer” means, unless otherwise noted, a chemical species that can be substituted by conventional substituents that do not interfere with the desired product;
  • (meth)acrylic refers to acrylate, methacrylate, acrylamide, and methacrylamide compounds, as well as alkyl and aryl compounds that have been substituted with an acrylate or methacrylate group.
  • the syrup of the present invention comprises from about 85 to 99.9 weight percent, preferably from about 90 to 99.9 weight percent, of a solvent monomer mixture and from about 0.1 to 15 weight percent, preferably from about 0.1 to 10 weight percent, of a solute polymer.
  • the solute polymers and the solvent monomer mixtures are based, in substantial part, on free radically-polymerizable ethylenically unsaturated monomers.
  • Ethylenically unsaturated monomers that do not contain a radiation-sensitive ⁇ -cleaving group comprise from about 95 to 100 pbw, preferably 97 to 100 pbw, of the monomer mixture. From 95 to 100% (by wt.) of the mer units of the polymer are also derived from such monomers.
  • Preferred free radically-polymerizable ethylenically unsaturated monomers are (meth)acrylic acid and its numerous well known derivatives.
  • a monomers monoethylenically- unsaturated monomers that are homopolymerizable to a polymer with a glass transition temperature (T ) less than about 0°C
  • a monomers preferably constitute from about 50 to 100 pbw, more preferably from about 60 to 95 pbw, of the solvent monomer mixture of the syrup of the present invention.
  • a monomers include (meth)acrylic acid esters of monohydric alcohols. Preferred among these are monofunctional esters of non-tertiary alcohols, particularly primary alcohols. Those (meth)acrylic acid esters wherein the alkyl portion of the ester contains from 4 to about 12 carbon atoms have been found to be especially useful.
  • Such monomers include, but are not limited to, isooctyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, decyl acrylate, and dodecyl acrylate.
  • Monethylenically unsaturated monomers that are homopolymerizable to a polymer with a T greater than about 50°C (hereinafter "B monomers”) can also be included in the free radically-polymerizable ethylenically unsaturated portion of the monomer mixture of the composition of the present invention.
  • B monomers when present, preferably constitute from about 0.1 to about 50 pbw, more preferably from about 5 to about 40 pbw of the monomer mixture.
  • useful B monomers include, but are not limited to, (meth)acrylic acid, itaconic acid, substituted (meth)acrylamides such as N,N-dimethylacrylamide and N- octylacrylamide, N-vinyl pyrrolidone, N-vinyl caprolactam, acrylonitrile, tetrahydrofurfuryl acrylate, isobornyl acrylate, abitol acrylate, and dicyclopentadienyl acrylate.
  • Ethylenically unsaturated monomers that comprise a radiation-sensitive ⁇ - cleaving group and that are copolymerizable with the aforementioned free radically-polymerizable ethylenically unsaturated monomers (hereinafter "C monomers") constitute from 0 to about 5 pbw, preferably 0 to 3 pbw, of the solvent monomer mixture of the syrup of the present invention.
  • C monomers include ethylenically unsaturated compounds having the general formula
  • R is H or a Ci to C 3 alkyl group, preferably H or a methyl group;
  • X is O or NH;
  • n is 0 or 1 ;
  • m is 0 or an integer from 1 to 5;
  • a, b, and c are independently 0 or 1 ;
  • M 1 is CH 2 or SiR*R 2 ;
  • M 2 is CR 3 R 4 or SiR'R 2 ;
  • M 3 is O, NH, C(O), C(O)O, C(O)NH, or OC(O)NH;
  • R 1 and R 2 are independently H or a Ci to C4 alkyl group;
  • R 3 and R 4 are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyi group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic O heteroatoms, or R 3 and R 4 taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;
  • G is a covalent bond, (CH 2 ) d , or (CH 2 ) d O where d is an integer from 1 to 4, preferably from 1 to 2;
  • Z is a radiation-sensitive ⁇ -cleaving group having the formula
  • Ar is a substituted arene having 6 to 12 carbon atoms, preferably a benzene group
  • R is hydrogen, a C ⁇ to C, 2 alkyl group, a C j to C 12 alkoxy group, or a phenyl group;
  • SUBSTITUTE SHEET (RULE 26j R is selected from the group consisting of
  • R is hydrogen, a C j to C ]2 alkyl group, a C j to C 12 alkoxy group, or a phenyl group, with the proviso that, when R and R 4 are both ortho to the carbonyl group of Z, together they can be one of
  • R , R , and R are independently a hydroxyl group, a phenyl group, a C j to C 6 alkyl group, a C j to C 6 alkoxy group, or a
  • R and R are independently hydrogen or a C j to C 6 alkyl group
  • At least one of R , R , and R is selected from the class consisting of hydroxyl, alkoxy, and — NR 10 R n groups;
  • M 1 and M 2 are not both SiR'R 2 .
  • Preferred ⁇ -cleaving type C monomers are those compounds described immediately above
  • Particularly preferred C monomers include
  • H 2 C CH COCH 2 CH 2 0 ( / V J C 'I C 1 H PIA #3
  • a variety of C monomers can be made by reacting an ethylenically unsaturated monomer comprising a first functional group (hereinafter “D compounds”) with a compound that comprises a radiation-sensitive ⁇ -cleaving group and a second functional group (hereinafter “E compounds”), the two functional groups being coreactive with each other.
  • D compounds ethylenically unsaturated monomer comprising a first functional group
  • E compounds a compound that comprises a radiation-sensitive ⁇ -cleaving group
  • the two functional groups being coreactive with each other.
  • D and E compounds are ethylenically unsaturated aliphatic, cycloaliphatic, and aromatic compounds having up to 36 carbon atoms, optionally one or more oxygen and/or nitrogen atoms, and at least one reactive functional group.
  • the first and second functional groups react, they form a covalent bond and link the D and E compounds.
  • Examples of useful functional groups include hydroxyl, secondary amino, azlactyl, oxazolinyl, acetyl acetonyl, carboxyl, isocyanato, epoxy, aziridinyl, acyl
  • D or E compound comprises an isocyanato group
  • the other preferably comprises a secondary amino or hydroxyl group
  • the D or E compound comprises a hydroxyl group
  • the other preferably comprises a carboxyl, isocyanato, epoxy, anhydride, or azlactyl group
  • the D or E compound comprises a carboxyl group
  • the other preferably comprises a hydroxyl, amino, epoxy, vinyloxy, or oxazolinyl group
  • the D or E compound comprises a vinyloxy group
  • the other preferably comprises a carboxyl group.
  • Representative examples of useful D compounds include hydroxyalkyl
  • (meth)acrylates such as 2-hydroxyethyl (meth)acrylate and 2-(2- hydroxyethoxy)ethyl (meth)acrylate; aminoalkyl (meth)acrylates such as 3- aminopropyl (meth)acrylate and 4-aminostyrene; azlactyl-substituted compounds such as 2-ethenyl-l,3-oxazolin-5-one and 2-propenyl-4,4-dimethyl-l,3-oxazolin-5- one; carboxy-substituted compounds such as (meth)acrylic acid and 4- carboxybenzyl (meth)acrylate; isocyanato-substituted compounds such as isocyanatoethyl (meth)acrylate and 4-isocyanatocyclohexyl (meth)acrylate; epoxy- substituted compounds such as glycidyl (meth)acrylate; aziridinyl-substituted compounds such as N-acryla
  • E compounds include functional group- substituted ⁇ -cleaving compounds such as 1 -(4-hydroxyphenyl)-2,2- dimethoxyethanone, 1 -[4-(2-hydroxyethyl)phenyl]-2,2-dimethoxyethanone, (4- isocyanatophenyl)-2,2-dimethoxy-2-phenylethanone, l- ⁇ 4-[2-(2,3- epoxypropoxy)phenyl] ⁇ -2,2-dimethyl-2-hydroxyethanone, l-[4-(2- aminoethoxy)phenyl]-2,2-dimethoxyethanone, and l-[4-(carbomethoxy)phenyl]- 2,2-dimethoxyethanone.
  • functional group- substituted ⁇ -cleaving compounds such as 1 -(4-hydroxyphenyl)-2,2- dimethoxyethanone, 1 -[4-(2-hydroxyethyl)phenyl]-2,2-dimethoxyethanone, (4-
  • a saturated energy-activated initiator of polymerization i.e., a source of free radicals other than a C monomer
  • energy-activated sources can be either heat- or UV radiation
  • heat-activated sources include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, azobis(isobutyronitrile), and methyl ethyl ketoperoxide.
  • Useful UV radiation-activated initiators include the benzoin ethers such as benzoin methyl ether and benzoin ispropyl ether; substituted acetophenones such as 2,2-diethoxyacetophenone available as IrgacureTM 651 photoinitiator (Ciba-Geigy Corp.; Ardsley, NY), 2,2-dimethoxy-2-phenyl-l- phenylethanone commonly available as EsacureTM KB-1 photoinitiator, (Sartomer Co.; West Chester, PA), and dimethoxyhydroxyacetophenone; substituted ⁇ - ketols such as 2-methyl-2-hydroxy propiophenone; aromatic sulfonyl chlorides such as 2-naphthalenesulfonyl chloride; and photoactive oximes such as 1-phenyl- l,2-propanedione-2-(O-ethoxycarbonyl)oxime.
  • substituted acetophenones such as 2,2-dieth
  • a saturated energy-activated source of free radicals can be present in an amount from about 0 to 3 pbw, preferably from 0.001 to about 1.0 pbw, more preferably from 0.005 to 0.5 pbw, per 100 pbw of the solvent monomer mixture.
  • the saturated energy-activated initiator of polymerization initiates polymerization of the free radically-polymerizable ethylenically unsaturated monomers (i.e., the A and B monomers).
  • ethylenically unsaturated monomers comprising a radiation-sensitive ⁇ -cleaving group i.e., C monomers
  • they also can be incorporated into the backbone chain of the polymer, resulting in radiation-sensitive ⁇ -cleaving groups pendent from the backbone chain.
  • the syrup can be exposed to heat only or to heat and UV-radiation so as to initiate polymerization of the monomer mixture.
  • the saturated photoinitiator can have an absorption spectum with an onset of absorption ( ⁇ A ) that is at least 25 nm apart from the onset of absorption of the radiation-sensitive ⁇ -cleaving group of
  • unsaturated hydrogen abstracting monomers and/or polyunsaturated monomers will provide a polymer with pendent groups that include hydrogen abstracting or unsaturated groups, respectively. Those groups can then be activated by means known in the art to allow for further polymerization, normally after the monomer-polymer composition (i.e., syrup) has been coated onto a substrate.
  • One or more free radically-polymerizable polyethylenically unsaturated monomers can be included in the monomer mixture or, preferably, added to the syrup.
  • polyethylenically unsaturated monomers that can be used include, but are not limited to, polyacrylic-functional monomers such as ethylene glycol diacrylate, propylene glycol dimethacrylate, trimethylolpropane triacrylate, 1,6- hexamethylenedioldiacrylate, pentaerythritol di-, tri-, and tetraacrylate, and 1,12- dodecanedioldiacrylate; olefinic-acrylic-functional monomers such as allyl methacrylate, 2-allyloxycarbonylamidoethyl methacrylate, and 2-allylaminoethyl acrylate; allyl 2-acrylamido-2,2-dimethylacetate; divinylbenzene;
  • microspheres can be added to the syrup of the present invention.
  • the resultant viscoelastomeric material has a foam ⁇ like appearance.
  • microspheres can be made from materials such as glass and polymers.
  • Glass microspheres as described in U.S. Patent No. 4,223,067, can have an average diameter of from about 5 to 200 ⁇ m, preferably from about 20 to about 80 ⁇ m.
  • Such microspheres can comprise from 5 to 65% (by vol.) of the viscoelastomeric material of the present invention.
  • a coated layer of the viscoelastomeric material is at least three times as thick, preferably at least seven times thick, as the diameter of the glass microspheres.
  • hollow polymeric microspheres having average diameters of from 5 to 200 ⁇ m are blended into the syrup of the present invention in amounts of from about 15 to about 75% (by vol.) prior to coating. Where such polymeric microspheres are used, they can be added into the syrup in an unexpanded form and subsequently heated to cause expansion. However, expanding them prior to addition is generally preferred because this helps to ensure that the hollow microspheres are substantially surrounded by at least a thin layer of viscoelastomeric material in the final article.
  • Useful polymeric microspheres are described in U.S. Patent Nos. 3,615,972, 4,075,238, and 4,287,308. Hollow polymeric microspheres are available under the tradename ExpancelTM (Eka Nobel Inc.; Marietta, GA). In expanded form, they have a specific density of approximately 0.02 to 0.036 g/cm .
  • a particularly useful adjuvant is fumed silica, especially hydrophobic silica as disclosed in U.S. Patent Nos. 4,710,536 and 4,749,590.
  • a layer of the viscoelastomeric material can contain from about 2 to about 15 pbw of hydrophobic silica having a surface area
  • compositions of the present invention include fillers, dyes, pigments, plasticizers, fibrous reinforcing agents, woven and nonwoven fabrics, foaming agents, antioxidants, stabilizers, fire retardants, tackifiers, electrically conductive particles, and viscosity adjusting agents.
  • chain transfer agents might be desirable to keep the molecular weight of the solute polymer below a desired value.
  • the amount of such adjuvants can vary from about 0.1 to 50% (by wt.), depending on the desired end use.
  • viscoelastomeric films can be prepared directly from the solvent monomer mixture (by quickly polymerizing a coated layer of the monomer to a polymer-monomer mixture), increasing the viscosity to a level more suitable for coating is preferred. This is readily accomplished by exposing the monomer(s) to a source of energy until about 0.1 to 15% (by wt.), preferably about 0.1 to 10%
  • the source of energy is heat
  • a heat-activated initiator of free radicals can be included in the composition.
  • the source of energy is UV radiation
  • a radiation-activated source of free radicals can be used (but is not required where the C monomer contains a radiation-sensitive group that produces free radicals on exposure to suitable radiation). Use of a radiation-activated source of free radicals is preferred in such situations, however.
  • composition (i.e., syrup) of the present invention is preferably prepared in situ by mixing one or more free radically-polymerizable ethylenically unsaturated monomers and 0 to 5 pbw of one or more of the above-described C monomers and then polymerizing the monomer(s) to form a solute polymer.
  • the monomers can be added in any order. Where no C monomer is present in the monomer mixture from which the syrup is formed (i.e., no radiation-sensitive ⁇ - cleaving groups are present in either the solute polymer or the solvent monomer mixture), some of these groups must be introduced into the syrup prior to formation of the viscoelastomeric material.
  • the in situ preparation of the composition just described allows for the production and solubilization of very high molecular weight polymers.
  • Such polymers preferably have a molecular weight of at least 500,000, more preferably at least 750,000, even more preferably at least 1,000,000, most preferably at least 1,500,000.
  • the solubilization of a separately made polymer of such a high molecular weight is very difficult. Therefore, the above-described in situ preparation method is the preferred manner of making the composition of the present invention.
  • a syrup of a coatable viscosity can be applied to a substrate, preferably a flexible carrier web, using any conventional coating means such as roller coating, dip coating, knife coating, and extrusion coating.
  • the substrate can further comprise any conventional coating means such as roller coating, dip coating, knife coating, and extrusion coating.
  • (RULE 26) comprise a release coating between the substrate and the syrup or on the side of the substrate opposite the side on which the syrup is coated.
  • a crosslinked viscoelastomeric material can be prepared therefrom in a variety of ways.
  • the remaining monomer(s) in the syrup are polymerized by exposure to radiation that activates the ⁇ -cleaving groups and facilitates polymerization.
  • this process can be carried out in a variety of ways.
  • Low intensity radiation is defined as 10 mW/cm or less (as measured in accordance with procedures approved by the United States National Institute of
  • High intensity radiation is defined as anything greater than 10 mW/cm 2 , preferably between 15 and 450 mW/cm . When such radiation is used, the viscoelastomeric material is formed directly from the syrup.
  • the amount of C monomer(s) can be about 0.04% (by wt.) and, yet, a viscoelastomeric material with balanced PSA properties can be obtained. Where the percentage (by wt.) of mer units derived from the C monomer(s) is less than about 0.4%, however, further
  • SUBS i i ⁇ uT ⁇ n ' LZT (RULE 25) processing is preferable Specifically, exposure to low intensity light followed by exposure to high intensity radiation can produce a crosslinked viscoelastomeric material with balanced PSA properties. About 0.05% (by wt ) of a multifunctional acrylate (e.g., hexanediol diacrylate) is preferably added to the syrup to aid in the formation of the viscoelastomeric material.
  • a multifunctional acrylate e.g., hexanediol diacrylate
  • Polymerization is preferably performed in an inert (i.e., oxygen free) atmosphere, such as a nitrogen atmosphere.
  • an inert i.e., oxygen free
  • Tolerance to oxygen can be increased by including in the syrup an oxidizable tin compound, as is taught in U.S. Patent No. 4,303,485, the teaching of which is incorporated herein by reference.
  • the syrup of the present invention can be cured in air by covering a layer of the photoactive coating with a plastic film that is substantially transparent to UV radiation but impervious to oxygen and irradiating the composition through that film using UV lamps that emit light in the wavelength range corresponding to the absorption maximum of any saturated photoinitiator used.
  • Several different commercially available lamps, including medium pressure mercury lamps and low- intensity fluorescent lamps, can be used. The radiation intensity of these lamps is preferably adjusted so that the radiation intensity at the surface of the coating is
  • the syrup preferably is exposed to a heat source either before or simultaneously with exposure to radiation of a wavelength that activates the ⁇ -cleaving groups present in the monomer and/or the polymer of the syrup.
  • the energy-activated initiator in the syrup of the present invention is a UV radiation-activated initiator
  • the syrup preferably is exposed first to a wavelength of radiation that activates the saturated initiator until the monomers polymerize to a coatable viscosity so that the syrup can be coated on a substrate. This coated composition is exposed to radiation of a wavelength to
  • the ⁇ -cleaving group of the C monomer is sensitive at an intensity of less than 10 mW/cm 2 (for a total dose of 30 to 800 mJ/cm 2 ) so as to further polymerize the monomers as well as crosslink the polymer chains.
  • the wavelengths used to activate the saturated initiator and the ⁇ -cleaving group can be the same as long as the wavelength is one at which the saturated initiator is more sensitive than the ⁇ -cleaving group.
  • composition comprising PIA #2 (which has an absorption spectrum with an absorption maximum at a wavelength of about 300 nm) as the C monomer and 2,2-dimethoxy-2-phenyl-l- phenylethanone (which is activated by radiation having a wavelength maximum at about 350 nm) as the saturated initiator.
  • PIA #2 which has an absorption spectrum with an absorption maximum at a wavelength of about 300 nm
  • 2,2-dimethoxy-2-phenyl-l- phenylethanone which is activated by radiation having a wavelength maximum at about 350 nm
  • Extent of polymerization can be monitored by measuring the refractive index of the adhesive layer.
  • Refractive index is a sensitive measure of the extent of polymerization. This method is commonly applied in polymerization kinetics work. See, for example, discussions about the method in Polymerization at Advanced Degrees of Conversion, G.P. Gladyshev and K M. Gibov, Keter Press, Jerusalem (1970). Change in refractive index occurs linearly with conversion of (meth)acrylate unsaturation.
  • crosslinked viscoelastomeric material of the present invention is a PSA
  • PSA displays balanced PSA properties (i.e., a good combination of adhesion, cohesion, stretchiness, and elasticity). This is believed to result from the crosslinked nature of the viscoelastomeric material.
  • Crosslinking in the present invention is quite different from the conventional mechanism of crosslinking provided by diacrylates where a similar increase in concentration of diacrylates results in a concomitant reduction in peel adhesion strength without an increase in static shear strength.
  • a multilayered tape that includes at least one cured layer derived from the syrup of the present invention is also within the scope of the present invention.
  • Such tapes can have a thin layer of a different PSA laminated thereto, so that the adhesive of the invention is being used as a backing or core layer.
  • the additional layer(s) can be any conventional adhesive known in the art; however,
  • additional adhesive layers include polymers of at least one alkyl (meth)acrylate monomer and a copolymerizable monomer hompolymerizable to a polymer with a T above about 50°C.
  • Multilayered tapes where a layer of a polyurethane, polychloroprene, polyacrylic foam, or polyethylene foam on which is coated a layer of the viscoelastomeric material of the present invention are also possible. Such tapes are often used to attain very high bond strengths. Further information about such constructions can be found in, for example, U.S. Patent Nos. 3,565,247,
  • the coated films of the present invention When the coated films of the present invention are cured, they preferably have a percent gel (corrected for any soluble tackifying resins and other additives) in the range of from 2 to 95% (by wt ), more preferably from 30 to 90% (by wt.), and most preferably from 50 to 80% (by wt.).
  • compositions of the present invention can also be used to make a cellular PSA membrane as is described in U.S. Patent No. 4,415,615, the teaching of which is incorporated herein by reference.
  • Objects and advantages of this invention are further illustrated by the following examples. The particular materials and amounts thereof, as well as other conditions and details, recited in these examples should not be used to unduly limit this invention.
  • the adhesive films described in the examples were cut into strips 1.27 cm in width. One of the release liners was removed and the strip was placed, with the adhesive side down, onto a piece of aluminum foil 125 ⁇ m thick and 1.6 cm wide. The remaining release liner film was removed from each of the strips to form a
  • test adhesive tape and adhered by its adhesive to a flat, rigid stainless steel plate with exactly 1.27 cm length of tape in contact with the plate.
  • a 1000 g weight at 25°C was placed over the bonded area for about 15 minutes.
  • the plate with the adhered tape was placed either at room temperature (RT) or in an air-circulating oven which had been preheated to 70°C.
  • RT room temperature
  • a weight was hung from the free end of the tape, with the panel tilted 2° from vertical to eliminate any peel forces.
  • the time (in minutes) at which the weight fell was designated the static shear RT (1000 g) or 70°C (500 g).
  • the test was discontinued after 10,000 minutes if no failure occurred and the result given as "10,000+".
  • Pieces of stainless steel were washed once with acetone and three times with a 50:50 water-isopropanol solution. Each adhesive film was adhered to a stainless steel backing for three days prior to being tested. Each sample was about 1.3 cm wide and had a 0.13 mm anodized aluminum backing (about 1.6 cm wide).
  • compositions including the following components were prepared: 90 pbw isooctyl acrylate (prepared according to processes available in the literature) 10 pbw acrylic acid 0.04 pbw 2,2-dimethoxy-2-phenyl-l-phenylethanone (Ciba Geigy).
  • PIA #2 available as ZLI 3331 from Ciba-Geigy
  • Table II the amount of PIA #2 (available as ZLI 3331 from Ciba-Geigy), shown in Table II.
  • PIA #2 available as ZLI 3331 from Ciba-Geigy
  • Table II the amount of PIA #2 (available as ZLI 3331 from Ciba-Geigy), shown in Table II.
  • Each mixture was degassed in a vacuum desiccator. The degassed mixture was partially polymerized by exposure for about 10 seconds to SylvaniaTM F15T8/350 BL 15-watt fluorescent black lamps.
  • the resulting syrup was knife coated onto a 50 ⁇ m biaxially-oriented poly( ethylene terephthalate) (PET) film at a thickness of 125 mm for Examples 1 to 5.
  • PET biaxially-oriented poly( ethylene terephthalate)
  • the coated films were passed through a coating device maintained under N 2 .
  • the films
  • the concentration of C monomer i.e., PIA #2
  • concentration of C monomer i.e., PIA #2
  • a concentration of C monomer of 0.2% (by wt.) or more in the adhesive is helpful in obtaining shear strengths of more than 5000 minutes at room temperature, and 0.3%) (by wt.) or more is helpful in obtaining shear strengths of more than 5000 minutes at 70°C.
  • Examples 6-9 Syrups were prepared as described in Examples 1 to 5 using mixtures of monomers as shown in Table III. (In Example 9, the monomer mixture also included a polystyrene macromer with a number average molecular weight of about 13,000.) The weight percentage of 2,2-dimethoxy-2-phenyl-l- phenylethanone and PIA #2 used in each syrup was 0.04%.
  • the mixtures were cured on a solvent-free silicone paper release liner at a thickness of 0.13 mm.
  • the samples were exposed to low intensity radiation for 145 seconds, the first third of the time at an intensity of 1.9 mW/cm 2 and the remainder of the time at an intensity of 4.2 mW/cm 2 .
  • the oxygen level was 250 ⁇ 20 ppm.
  • the samples were exposed to high intensity radiation at an average intensity of 112 mW/cm 2 for about five seconds. The conversion of all the polymers was greater than 98%. Peel strength values were determined after the peel samples were adhered to the stainless steel substrates for three days.
  • Static shear strength values were measured using stainless steel substrates cleaned once with acetone and three times with a 50:50 isopropanol/water mixture. 2.54 cm x 1.27 cm samples were prepared and a 1000 g load was used at room temperature and a 500 g load was used at 70°C. The shear samples were adhered to stainless steel for four hours prior to hanging. (0.13 mm anodized aluminum backings were used for all of the samples.) The time until failure is the average of two samples (in minutes).
  • Example CI shows that, when using HDDA by itself, balanced properties (i.e., a PSA with high room temperature shear, high 70°C shear, and high peel strength) are not obtained.
  • Example C2 shows that too low of a loading level of PIA, when used with HDDA, also does not provide balanced static shear strength properties. However, at loading levels of about 0.1 pph of PIA used in combination with high intensity radiation and about 0.05 pph HDDA, balanced shear properties can be achieved.
  • Various modifications and alterations that do not depart from the scope and spirit of this invention will become apparent to those skilled in the art. This invention is not to be unduly limited to the illustrative embodiments set forth therein.

Abstract

Solute polymers in solvent monomers form a coatable syrup that can be cured to a viscoelastomeric material when radiation-sensitive α-cleaving groups in either the polymer or one of the monomers are exposed to ultraviolet radiation. The solute polymers can be formed from the solvent monomers or be added thereto to form the syrup.

Description

ACRYLIC SYRUP CURABLE TO A CROSSLINKED VISCOELASTOMERIC MATERIAL
This application is a Continuation-in-Part of U.S. Serial No. 08/282,058 filed July 29, 1994, currently pending.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention describes a viscoelastomeric material with high shear at ambient and elevated temperatures prepared from a blend of ethylenically unsaturated monomers. A process for making this material is also described.
2. Background Information
Pressure sensitive adhesives (PSAs) made by photopolymerizing an alkyl acrylate and a polar copolymerizable monomer are known in the art. See, e.g., U.S. Patent Nos. RE 24,906; 4,181,755; 4,364,972; and 4,243,500. Acrylic-based PSAs exhibit good adherence to high energy (i.e., polar) substrates such as metal and painted steel surfaces but generally exhibit lower adhesion to low energy (i.e., nonpolar) substrates such as polyethylene and polypropylene.
Solvent-processed acrylic PSA compositions can be crosslinked by adding a polyfunctional crosslinking agent that reacts with a reactive group present in the polymer. See, e.g., Japanese Kokoku 58[1983]-046236 in which is described a solvent-processed crosslinked acrylic PSA with excellent cohesion that is the reaction product of (a) a polyisocyanate, prepared by reacting (1) an acrylic copolymer having a molecular weight between 1,000 and 30,000 and from 1.7 to 5.0 functional groups that can react with an isocyanate group with (2) a diisocyanate, so that the ratio of isocyanate groups per coreactive functional group is about 2: 1, and (b) an adherent copolymer comprising functional groups that can react with an isocyanate group. Like any solvent processing technique, however, the preparation of thick adhesives is difficult because the solvent causes bubbling in the adhesive and the emission of solvent vapors into the atmosphere is undesirable.
To avoid environmental pollution, manufacturing processes that do not require the use of volatile solvents have become of great interest. An early step in this direction for the manufacture of PSA tape was the process described in Belgium Patent No. 675,420. In this process, flexible carriers are coated with acrylic monomers, or mixtures of such monomers with copolymerizable compounds, with the possible addition of a thickening and/or initiating agent, and the monomers are polymerized directly on the carrier using ultraviolet radiation. Hot melt coating a PSA composition eliminates the necessity of solvent processing. To hot melt process an adhesive composition, the composition must be uncrosslinked during the coating process; however, to achieve a PSA with balanced properties (i.e., peel and shear adhesion), the composition must be crosslinked. In hot melt coating processes, this is usually done by exposure to high energy radiation (e.g., E-beam or high intensity ultraviolet radiation). When high intensity ultraviolet radiation is used, a photoactive crosslinking species such as benzophenone is generally added to the composition. However, this often results in PSAs that display cure gradients. Additionally, thicker sections of PSA compositions cannot be cured this way. A more efficient method of photocrosslinking involves incorporating hydrogen abstracting moieties into the polymer backbone prior to coating. Such polymers can be hot melt coated and subsequently cured by conventional irradiation techniques. This process is typified by U.S. Patent No. 4,737,599 where a PSA with good adhesion to skin is described. That process is much more efficient than the high intensity irradiation method described immediately above, but the preparation of a thick PSA section that does not display a cure gradient is not described.
The cohesive strength of an acrylic PSA can be increased without unduly affecting its compliance by utilizing a photoactive crosslinking agent in conjunction with a photoinitiator. See, e.g., U.S. Patent Nos. 4,181,752;
4,329,384; 4,330,590; 4,391,687, and 5,202,361. Useful photoactive crosslinking agents include various aldehydes, quinones, and particularly certain chromophore- substituted halomethyl-s-triazines (because they provide desirably shortened reaction times and somewhat greater tolerance to oxygen over the non- halomethyl-containing agents), although their use can result in evolution of HC1 during polymerization.
An ultraviolet (UV) radiation-curable composition that includes 20 to 99% (by wt.) of a copolymer of ethylenically unsaturated monomers, 1 to 80% (by wt.) ethylenically unsaturated monomers, and 0 to 20% (by wt.) of one or more polyethylenically unsaturated compounds is described in U.S. Patent No. 5,180,756.
Copolymerizable photoinitiators such as 2-[4-(2-hydroxy-2,2-dimethyl-l- oxopropyl)phenoxy]ethyl 2-propenoate and their use in the polymerization of ethylenically unsaturated compounds is disclosed in U.S. Patent No. 4,922,004. Japanese Kokai 2[1990]-248482 describes a photocurable PSA obtained by reacting (a) 30 to 50 parts by weight (pbw) of a copolymer of an acrylic acid alkyl ester, a copolymerizable ethylenically unsaturated monomer having a polar group, and a copolymerizable monomer with a photosensitizing group (such as 2- acryloyloxybenzophenone or 1 -acryloyloxy-2-[4-(4-chlorobenzoyl)benzoyl- oxy]ethane); (b) 40 to 60 pbw of an aryloxy acrylic monomer such as phenoxyethyl acrylate or nonylphenoxyethyl acrylate; and (c) a tackifying resin. The composition is cured using a total dose of energy of 300 to 800 mJ/cm2 from a high pressure mercury lamp. Such high intensity ultraviolet radiation is likely to produce an adhesive that has a shear value less than 100 minutes.
Similarly, DE 42 03 183 Cl (Germany) discloses a method for producing PSA layers comprising the steps of thickening a monomer mixture that includes a photoinitiator with a separately made, solvent-free saturated UV-reactive polyacrylate; coating the thickened mixture onto a substrate; and irradiating the coated substrate. The separately made polymer comprises side chains that, when irradiated, participate in crosslinking reactions. The sole example involves the addition of a commercially available polymer having a molecular weight of about 200,000 to a monomer mixture that is then polymerized.
buoό'u i ϋ i c ώπcti iU c k ) The shear values of PSAs prepared by actinically irradiating acrylic monomers can be enhanced by the addition of polyacrylic crosslinking agents. See, e.g., U.S. Patent No. 4,379,201. Such PSAs involve networks and are sensitive to processing conditions. A composition that can be radiation cured to provide thick, high molecular weight PSA compositions with outstanding properties has not been previously described.
SUMMARY OF THE INVENTION Briefly, the present invention provides a syrup, preferably a syrup of a coatable viscosity, curable to a crosslinked viscoelastomeric material comprising: a) about 85 to 99.9 weight percent, preferably about 90 to 99.9 weight percent, of a solvent monomer mixture comprising 95 to 100 pbw, preferably 97 to 100 pbw, of at least one free radically-polymerizable ethylenically unsaturated monomer and 0 to 5 pbw, preferably 0 to 3 pbw, of an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group; b) about 0.1 to 15 weight percent, preferably about 0.1 to 10 weight percent, of a solute polymer, preferably a polymer having a molecular weight of at least 500,000, comprising about 95 to 100 weight percent mer units derived from one or more free radically-polymerizable ethylenically unsaturated monomers and about 0 to 5 weight percent mer units derived from an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group, with the proviso that the weight percent of the second component of the polymer cannot be zero when the monomer mixture comprises zero parts by weight of the ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group; c) from 0 to 5 pbw, preferably 0.01 to 0.30 pbw, of a free radically- polymerizable polyethylenically unsaturated monomer; and d) from 0 to 3 pbw, preferably 0.001 to 1.0 pbw of a saturated energy- activated initiator of polymerization (i.e., an energy-activated initiator of polymerization that is free of ethylenic unsaturation).
SUBSTITUTE SHEET (RULE 2 ) In another aspect, the present invention provides a process for making a crosslinked viscoelastomeric material comprising the steps: a) providing a composition comprising a solvent monomer mixture comprising at least one free radically-polymerizable ethylenically unsaturated monomer and 0 to 5 pbw, preferably 0 to 3 pbw, of an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group and 0 to 3 pbw, preferably 0.001 to 0.5 pbw, of a saturated energy-activated initiator of polymerization, preferably a saturated radiation-activated initiator of polymerization, with the proviso that the amount of saturated initiator must be greater than zero when the amount of ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group is zero; b) exposing the composition to energy, preferably radiative energy, so as to partially polymerize the monomer mixture and form a coatable syrup; c) adding to the syrup, based on the total amount of monomer initially present in said monomer mixture, 0 to 3 pbw, preferably 0.001 to 0.5 pbw, of a saturated energy-activated initiator of polymerization, preferably a saturated radiation-activated initiator of polymerization; 0 to 3 pbw of an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group, with the proviso that the amount of ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group added to the syrup must be greater than zero when the amount of ethylenically unsaturated monomer comprising a radiation- sensitive α-cleaving group in the monomer mixture is zero; and/or 0 to 5 pbw, preferably 0.01 to 0.30 pbw, of a polyethylenically unsaturated monomer; and d) exposing the syrup to energy that activates the initiator and the radiation- sensitive α-cleaving group so as to form the crosslinked viscoelastomeric material.
The viscoelastomeric material produced from the above syrup is also described. The syrup optionally can be coated on a substrate prior to being irradiated, and such articles are also described.
The coatable syrup of the present invention is polymerizable to a viscoelastomeric material that can be crosslinked directly. The viscoelastomeric material is preferably a PSA having high shear at both ambient and elevated
SUBSTITU VE G.-.ΞET (ή l.L __^j temperatures. This syrup comprises a solute polymer in a solvent monomer mixture. The polymer preferably has a very high molecular weight, preferably at least 500,000, more preferably at least 750,000, even more preferably at least 1,000,000, most preferably at least 1,500,000. One or both of the polymer and monomer contains at least one radiation-sensitive α-cleaving group that, upon exposure to UV radiation, is activated to enable curing. The cured product is a viscoelastomeric material.
Where the polymer of the syrup of the present invention contains side chains that comprise radiation-sensitive α-cleaving groups activatable by UV radiation, free radicals are formed that allow for growth of the side chain by addition of ethylenically unsaturated monomer(s). These growing side chains become entangled with other such side chains, or react with other such side chains, to produce a crosslinked viscoelastomeric material. Where the polymer does not include radiation-sensitive α-cleaving group-containing side chains, the monomer mixture contains enough ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group to form, upon exposure to UV radiation, a polymer that includes radiation-sensitive α-cleaving groups in side chains. In this embodiment, the original polymer chains become entangled with the newly formed polymer chains to form a crosslinked network. Where no ethylenically unsaturated monomer comprising a radiation- sensitive α-cleaving group is present in the initial monomer mixture, some polymer that includes side chains comprising the aforementioned radiation- sensitive α-cleaving groups or some monomer that contains a radiation-sensitive α-cleaving group must be added to the syrup prior to formation of the viscoelastomeric material therefrom (i.e., polymerization of the monomer(s) of the monomer mixture). Preferably, however, the solute polymer is prepared in situ, i.e., directly from the solvent monomer mixture. This eliminates the need for solubilizing a separately made polymer in a monomer mixture and allows very high molecular weight polymers to be formed and solubilized. Viscoelastomeric materials produced from the syrup of the present invention can be used as PSAs, vibration damping materials, transfer adhesives, structural adhesives, protective coatings, and the like. Advantageously, the syrup of the present invention can have a coatable viscosity and can therefore be applied to a substrate prior to curing, thus allowing for the simple production of articles comprising one or more layers of the aforementioned viscoelastomeric material.
Unless otherwise indicated, the following definitions apply in this application:
"group" or "compound" or "monomer" or "polymer" means, unless otherwise noted, a chemical species that can be substituted by conventional substituents that do not interfere with the desired product; and
"(meth)acrylic" refers to acrylate, methacrylate, acrylamide, and methacrylamide compounds, as well as alkyl and aryl compounds that have been substituted with an acrylate or methacrylate group.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The syrup of the present invention comprises from about 85 to 99.9 weight percent, preferably from about 90 to 99.9 weight percent, of a solvent monomer mixture and from about 0.1 to 15 weight percent, preferably from about 0.1 to 10 weight percent, of a solute polymer.
In the syrup of the present invention, the solute polymers and the solvent monomer mixtures are based, in substantial part, on free radically-polymerizable ethylenically unsaturated monomers. Ethylenically unsaturated monomers that do not contain a radiation-sensitive α-cleaving group comprise from about 95 to 100 pbw, preferably 97 to 100 pbw, of the monomer mixture. From 95 to 100% (by wt.) of the mer units of the polymer are also derived from such monomers. Preferred free radically-polymerizable ethylenically unsaturated monomers are (meth)acrylic acid and its numerous well known derivatives.
Particularly preferred among such monomers are monoethylenically- unsaturated monomers that are homopolymerizable to a polymer with a glass transition temperature (T ) less than about 0°C (hereinafter "A monomers"). These monomers preferably constitute from about 50 to 100 pbw, more preferably from about 60 to 95 pbw, of the solvent monomer mixture of the syrup of the present invention. Common examples of A monomers include (meth)acrylic acid esters of monohydric alcohols. Preferred among these are monofunctional esters of non-tertiary alcohols, particularly primary alcohols. Those (meth)acrylic acid esters wherein the alkyl portion of the ester contains from 4 to about 12 carbon atoms have been found to be especially useful. Such monomers include, but are not limited to, isooctyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, decyl acrylate, and dodecyl acrylate. Monethylenically unsaturated monomers that are homopolymerizable to a polymer with a T greater than about 50°C (hereinafter "B monomers") can also be included in the free radically-polymerizable ethylenically unsaturated portion of the monomer mixture of the composition of the present invention. B monomers, when present, preferably constitute from about 0.1 to about 50 pbw, more preferably from about 5 to about 40 pbw of the monomer mixture. Examples of useful B monomers include, but are not limited to, (meth)acrylic acid, itaconic acid, substituted (meth)acrylamides such as N,N-dimethylacrylamide and N- octylacrylamide, N-vinyl pyrrolidone, N-vinyl caprolactam, acrylonitrile, tetrahydrofurfuryl acrylate, isobornyl acrylate, abitol acrylate, and dicyclopentadienyl acrylate.
Ethylenically unsaturated monomers that comprise a radiation-sensitive α- cleaving group and that are copolymerizable with the aforementioned free radically-polymerizable ethylenically unsaturated monomers (hereinafter "C monomers") constitute from 0 to about 5 pbw, preferably 0 to 3 pbw, of the solvent monomer mixture of the syrup of the present invention. Preferred C monomers include ethylenically unsaturated compounds having the general formula
SUBSTITUTE SHEET (RULE 26;
Figure imgf000011_0001
wherein
R is H or a Ci to C3 alkyl group, preferably H or a methyl group; X is O or NH; n is 0 or 1 ; m is 0 or an integer from 1 to 5; a, b, and c are independently 0 or 1 ; M1 is CH2 or SiR*R2; M2 is CR3R4 or SiR'R2;
M3 is O, NH, C(O), C(O)O, C(O)NH, or OC(O)NH; R1 and R2 are independently H or a Ci to C4 alkyl group;
R3 and R4 are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyi group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic O heteroatoms, or R3 and R4 taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;
G is a covalent bond, (CH2)d, or (CH2)dO where d is an integer from 1 to 4, preferably from 1 to 2;
Z is a radiation-sensitive α-cleaving group having the formula
Figure imgf000011_0002
in which
Ar is a substituted arene having 6 to 12 carbon atoms, preferably a benzene group;
R is hydrogen, a C{ to C,2 alkyl group, a Cj to C12 alkoxy group, or a phenyl group; and
SUBSTITUTE SHEET (RULE 26j R is selected from the group consisting of
Figure imgf000012_0001
in which
4
R is hydrogen, a Cj to C]2 alkyl group, a Cj to C12 alkoxy group, or a phenyl group, with the proviso that, when R and R4 are both ortho to the carbonyl group of Z, together they can be one of
-C— — S- and — CH.—
and
6 7 8 .
R , R , and R are independently a hydroxyl group, a phenyl group, a Cj to C6 alkyl group, a Cj to C6 alkoxy group, or a
10 11 10 11
— NR R group, wherein R and R are independently hydrogen or a Cj to C6 alkyl group,
9 6 7 8 with the proviso that, when R is CR R R , one of the following must be true:
6 7 8
(1) at least one of R , R , and R is selected from the class consisting of hydroxyl, alkoxy, and — NR10Rn groups;
6 7 8
(2) any two of R , R , and R together are one of — C H2 — and
— OC H2 O — wherein p is either 2 or 3 so that they, together with the carbon atoms to which they are attached, form a 5- or 6-membered ring; and
(3) any two of R , R , and R together are a carbonyl group,
6 7 8 . provided that the remaining one of R , R , and R is selected
SUBSTITUTE Si IE ET < 10 π from the class consisting of hydroxy, alkoxy, — NR R , and phenyl groups.
Preferably, where m is not 0, M1 and M2 are not both SiR'R2. Preferred α-cleaving type C monomers are those compounds described immediately above
9 where R is t-,6 i 7 — C-R7
and/or Ar (from Z) being a benzenetriyl group.
Particularly preferred C monomers include
Figure imgf000013_0001
OCH3
H2C=CH COCH2CH20 ( / V J C 'I C 1 H PIA #3
OCH3
Figure imgf000013_0002
Figure imgf000014_0001
Figure imgf000014_0002
Figure imgf000014_0003
A variety of C monomers can be made by reacting an ethylenically unsaturated monomer comprising a first functional group (hereinafter "D compounds") with a compound that comprises a radiation-sensitive α-cleaving group and a second functional group (hereinafter "E compounds"), the two functional groups being coreactive with each other. Preferred D and E compounds are ethylenically unsaturated aliphatic, cycloaliphatic, and aromatic compounds having up to 36 carbon atoms, optionally one or more oxygen and/or nitrogen atoms, and at least one reactive functional group. When the first and second functional groups react, they form a covalent bond and link the D and E compounds.
Examples of useful functional groups include hydroxyl, secondary amino, azlactyl, oxazolinyl, acetyl acetonyl, carboxyl, isocyanato, epoxy, aziridinyl, acyl
SUBST- ΠJTP HEFT RULE 26) halide, vinyloxy, and cyclic anhydride groups. Preferred among these are isocyanato, hydroxyl, carboxyl, and vinyloxy groups. Where the D or E compound comprises an isocyanato group, the other preferably comprises a secondary amino or hydroxyl group; where the D or E compound comprises a hydroxyl group, the other preferably comprises a carboxyl, isocyanato, epoxy, anhydride, or azlactyl group; where the D or E compound comprises a carboxyl group, the other preferably comprises a hydroxyl, amino, epoxy, vinyloxy, or oxazolinyl group; and where the D or E compound comprises a vinyloxy group, the other preferably comprises a carboxyl group. Representative examples of useful D compounds include hydroxyalkyl
(meth)acrylates such as 2-hydroxyethyl (meth)acrylate and 2-(2- hydroxyethoxy)ethyl (meth)acrylate; aminoalkyl (meth)acrylates such as 3- aminopropyl (meth)acrylate and 4-aminostyrene; azlactyl-substituted compounds such as 2-ethenyl-l,3-oxazolin-5-one and 2-propenyl-4,4-dimethyl-l,3-oxazolin-5- one; carboxy-substituted compounds such as (meth)acrylic acid and 4- carboxybenzyl (meth)acrylate; isocyanato-substituted compounds such as isocyanatoethyl (meth)acrylate and 4-isocyanatocyclohexyl (meth)acrylate; epoxy- substituted compounds such as glycidyl (meth)acrylate; aziridinyl-substituted compounds such as N-acrylaziridine and l-(2-propenyl)-aziridine; and acyl halides such as (meth)acryl chloride.
Representative examples of E compounds include functional group- substituted α-cleaving compounds such as 1 -(4-hydroxyphenyl)-2,2- dimethoxyethanone, 1 -[4-(2-hydroxyethyl)phenyl]-2,2-dimethoxyethanone, (4- isocyanatophenyl)-2,2-dimethoxy-2-phenylethanone, l-{4-[2-(2,3- epoxypropoxy)phenyl]}-2,2-dimethyl-2-hydroxyethanone, l-[4-(2- aminoethoxy)phenyl]-2,2-dimethoxyethanone, and l-[4-(carbomethoxy)phenyl]- 2,2-dimethoxyethanone.
If desired, a saturated energy-activated initiator of polymerization (i.e., a source of free radicals other than a C monomer) can be used in forming the polymer component of the syrup of the present invention from the monomer component. These energy-activated sources can be either heat- or UV radiation
:-' it- ": ■ ■ ;LL . . :L\ _χ f activated. Examples of heat-activated sources include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, azobis(isobutyronitrile), and methyl ethyl ketoperoxide. Useful UV radiation-activated initiators include the benzoin ethers such as benzoin methyl ether and benzoin ispropyl ether; substituted acetophenones such as 2,2-diethoxyacetophenone available as Irgacure™ 651 photoinitiator (Ciba-Geigy Corp.; Ardsley, NY), 2,2-dimethoxy-2-phenyl-l- phenylethanone commonly available as Esacure™ KB-1 photoinitiator, (Sartomer Co.; West Chester, PA), and dimethoxyhydroxyacetophenone; substituted α- ketols such as 2-methyl-2-hydroxy propiophenone; aromatic sulfonyl chlorides such as 2-naphthalenesulfonyl chloride; and photoactive oximes such as 1-phenyl- l,2-propanedione-2-(O-ethoxycarbonyl)oxime. Particularly preferred among these are the substituted acetophenones. A saturated energy-activated source of free radicals can be present in an amount from about 0 to 3 pbw, preferably from 0.001 to about 1.0 pbw, more preferably from 0.005 to 0.5 pbw, per 100 pbw of the solvent monomer mixture.
When present and upon activation through introduction of appropriate energy, the saturated energy-activated initiator of polymerization initiates polymerization of the free radically-polymerizable ethylenically unsaturated monomers (i.e., the A and B monomers). When ethylenically unsaturated monomers comprising a radiation-sensitive α-cleaving group (i.e., C monomers) are also present, they also can be incorporated into the backbone chain of the polymer, resulting in radiation-sensitive α-cleaving groups pendent from the backbone chain.
Where a saturated heat-activated initiator is used with a monomer mixture that includes at least one C monomer, the syrup can be exposed to heat only or to heat and UV-radiation so as to initiate polymerization of the monomer mixture.
Where a saturated UV radiation-activated initiator is used with a monomer mixture that includes at least one C monomer, the saturated photoinitiator can have an absorption spectum with an onset of absorption (λA) that is at least 25 nm apart from the onset of absorption of the radiation-sensitive α-cleaving group of
, — v. . _ _.-. --U J the C monomer (λβ). This allows for crosslinking, through activation of the α- cleaving group, to occur after the saturated photoinitiator has initiated polymerization.
Inclusion of unsaturated hydrogen abstracting monomers and/or polyunsaturated monomers will provide a polymer with pendent groups that include hydrogen abstracting or unsaturated groups, respectively. Those groups can then be activated by means known in the art to allow for further polymerization, normally after the monomer-polymer composition (i.e., syrup) has been coated onto a substrate. One or more free radically-polymerizable polyethylenically unsaturated monomers can be included in the monomer mixture or, preferably, added to the syrup. Use of such monomer(s) allows for a reduction in the amount of ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group necessary to produce the viscoelastomeric material of the present invention. Examples of polyethylenically unsaturated monomers that can be used include, but are not limited to, polyacrylic-functional monomers such as ethylene glycol diacrylate, propylene glycol dimethacrylate, trimethylolpropane triacrylate, 1,6- hexamethylenedioldiacrylate, pentaerythritol di-, tri-, and tetraacrylate, and 1,12- dodecanedioldiacrylate; olefinic-acrylic-functional monomers such as allyl methacrylate, 2-allyloxycarbonylamidoethyl methacrylate, and 2-allylaminoethyl acrylate; allyl 2-acrylamido-2,2-dimethylacetate; divinylbenzene; and the like.
If desired, microspheres can be added to the syrup of the present invention. When microspheres are used, the resultant viscoelastomeric material has a foam¬ like appearance. These microspheres can be made from materials such as glass and polymers.
Glass microspheres, as described in U.S. Patent No. 4,223,067, can have an average diameter of from about 5 to 200 μm, preferably from about 20 to about 80 μm. Such microspheres can comprise from 5 to 65% (by vol.) of the viscoelastomeric material of the present invention. Preferably, a coated layer of the viscoelastomeric material is at least three times as thick, preferably at least seven times thick, as the diameter of the glass microspheres.
£25) Alternatively, hollow polymeric microspheres having average diameters of from 5 to 200 μm are blended into the syrup of the present invention in amounts of from about 15 to about 75% (by vol.) prior to coating. Where such polymeric microspheres are used, they can be added into the syrup in an unexpanded form and subsequently heated to cause expansion. However, expanding them prior to addition is generally preferred because this helps to ensure that the hollow microspheres are substantially surrounded by at least a thin layer of viscoelastomeric material in the final article. Useful polymeric microspheres are described in U.S. Patent Nos. 3,615,972, 4,075,238, and 4,287,308. Hollow polymeric microspheres are available under the tradename Expancel™ (Eka Nobel Inc.; Marietta, GA). In expanded form, they have a specific density of approximately 0.02 to 0.036 g/cm .
A particularly useful adjuvant is fumed silica, especially hydrophobic silica as disclosed in U.S. Patent Nos. 4,710,536 and 4,749,590. In another embodiment of the present invention, a layer of the viscoelastomeric material can contain from about 2 to about 15 pbw of hydrophobic silica having a surface area
2 of at least 10 m /g.
Other useful adjuvants that can be blended into the syrup of the present invention include fillers, dyes, pigments, plasticizers, fibrous reinforcing agents, woven and nonwoven fabrics, foaming agents, antioxidants, stabilizers, fire retardants, tackifiers, electrically conductive particles, and viscosity adjusting agents. For some applications, the use of chain transfer agents might be desirable to keep the molecular weight of the solute polymer below a desired value. The amount of such adjuvants can vary from about 0.1 to 50% (by wt.), depending on the desired end use.
Although viscoelastomeric films can be prepared directly from the solvent monomer mixture (by quickly polymerizing a coated layer of the monomer to a polymer-monomer mixture), increasing the viscosity to a level more suitable for coating is preferred. This is readily accomplished by exposing the monomer(s) to a source of energy until about 0.1 to 15% (by wt.), preferably about 0.1 to 10%
SUBSTITUTE Si icET (RULE 26) (by wt ), more preferably about 3 to 7% (by wt.), of the monomers have polymerized. If the source of energy is heat, a heat-activated initiator of free radicals can be included in the composition. If the source of energy is UV radiation, a radiation-activated source of free radicals can be used (but is not required where the C monomer contains a radiation-sensitive group that produces free radicals on exposure to suitable radiation). Use of a radiation-activated source of free radicals is preferred in such situations, however.
The composition (i.e., syrup) of the present invention is preferably prepared in situ by mixing one or more free radically-polymerizable ethylenically unsaturated monomers and 0 to 5 pbw of one or more of the above-described C monomers and then polymerizing the monomer(s) to form a solute polymer. The monomers can be added in any order. Where no C monomer is present in the monomer mixture from which the syrup is formed (i.e., no radiation-sensitive α- cleaving groups are present in either the solute polymer or the solvent monomer mixture), some of these groups must be introduced into the syrup prior to formation of the viscoelastomeric material. This can be done by adding C monomer to the syrup after formation of the solute polymer or by adding to the syrup a second polymer (made separately from the syrup) that contains mer units with the above-described radiation-sensitive α-cleaving groups pendent therefrom. Adjuvants, when desired, can thereafter be blended into the mixture.
The in situ preparation of the composition just described allows for the production and solubilization of very high molecular weight polymers. Such polymers preferably have a molecular weight of at least 500,000, more preferably at least 750,000, even more preferably at least 1,000,000, most preferably at least 1,500,000. The solubilization of a separately made polymer of such a high molecular weight is very difficult. Therefore, the above-described in situ preparation method is the preferred manner of making the composition of the present invention.
A syrup of a coatable viscosity can be applied to a substrate, preferably a flexible carrier web, using any conventional coating means such as roller coating, dip coating, knife coating, and extrusion coating. The substrate can further
SUBSTITU" v. f l _. | (RULE 26) comprise a release coating between the substrate and the syrup or on the side of the substrate opposite the side on which the syrup is coated.
Once a syrup has been prepared, a crosslinked viscoelastomeric material can be prepared therefrom in a variety of ways. In each method, the remaining monomer(s) in the syrup are polymerized by exposure to radiation that activates the α-cleaving groups and facilitates polymerization. However, this process can be carried out in a variety of ways.
One way to make the viscoelastomeric material from the remaining monomer(s) is to irradiate the syrup with both high and low intensity UV
2 radiation. Low intensity radiation is defined as 10 mW/cm or less (as measured in accordance with procedures approved by the United States National Institute of
Standards and Technology as, for example, with a UVTMAP™ UM 365 L-S radiometer manufactured by Electronic Instrumentation & Technology, Inc., in
Sterling, VA), preferably in the wavelength region of 200 to 600 nm, more preferably 280 to 400 nm. High intensity radiation is defined as anything greater than 10 mW/cm 2 , preferably between 15 and 450 mW/cm . When such radiation is used, the viscoelastomeric material is formed directly from the syrup.
Other ways of making the viscoelastomeric material involve initially exposing the syrup to only low intensity radiation. Syrup formulations that produce high performance viscoelastomeric materials will depend on the particular crosslinker (i.e., C monomer) and its ability to be activated by the particular radiation used. Generally, where the percentage (by wt.) of mer units derived from the C monomer(s) is about 0.4% or greater and.no polyethylenically unsaturated monomer is present and curing is performed in an environment that is substantially free of oxygen, this low intensity exposure is sufficient to make a viscoelastomeric material that is a PSA with balanced properties. Where curing occurs between radiation transparent release liners, the amount of C monomer(s) can be about 0.04% (by wt.) and, yet, a viscoelastomeric material with balanced PSA properties can be obtained. Where the percentage (by wt.) of mer units derived from the C monomer(s) is less than about 0.4%, however, further
SUBS i iϊuTΞ n'LZT (RULE 25) processing is preferable Specifically, exposure to low intensity light followed by exposure to high intensity radiation can produce a crosslinked viscoelastomeric material with balanced PSA properties. About 0.05% (by wt ) of a multifunctional acrylate (e.g., hexanediol diacrylate) is preferably added to the syrup to aid in the formation of the viscoelastomeric material.
Polymerization is preferably performed in an inert (i.e., oxygen free) atmosphere, such as a nitrogen atmosphere. Tolerance to oxygen can be increased by including in the syrup an oxidizable tin compound, as is taught in U.S. Patent No. 4,303,485, the teaching of which is incorporated herein by reference. The syrup of the present invention can be cured in air by covering a layer of the photoactive coating with a plastic film that is substantially transparent to UV radiation but impervious to oxygen and irradiating the composition through that film using UV lamps that emit light in the wavelength range corresponding to the absorption maximum of any saturated photoinitiator used. Several different commercially available lamps, including medium pressure mercury lamps and low- intensity fluorescent lamps, can be used. The radiation intensity of these lamps is preferably adjusted so that the radiation intensity at the surface of the coating is
2 2 less than 20 mW/cm , preferably 0.5 to 6 mW/cm , each having emission maxima between 200 and 600 nm, preferably between 280 and 400 nm. Maximum efficiency and rate of polymerization is dictated by the relationship between emission properties of the radiation source and the absorption properties of the photoactive compounds employed.
Where the saturated energy-activated initiator in the syrup of the present invention is heat-activated, the syrup preferably is exposed to a heat source either before or simultaneously with exposure to radiation of a wavelength that activates the α-cleaving groups present in the monomer and/or the polymer of the syrup. Where saturated the energy-activated initiator in the syrup of the present invention is a UV radiation-activated initiator, the syrup preferably is exposed first to a wavelength of radiation that activates the saturated initiator until the monomers polymerize to a coatable viscosity so that the syrup can be coated on a substrate. This coated composition is exposed to radiation of a wavelength to
l -JW 1 l I _ . _. _ . |_._, , ^, l ,_ _.j_ __ _J which the α-cleaving group of the C monomer is sensitive at an intensity of less than 10 mW/cm 2 (for a total dose of 30 to 800 mJ/cm 2 ) so as to further polymerize the monomers as well as crosslink the polymer chains. The wavelengths used to activate the saturated initiator and the α-cleaving group can be the same as long as the wavelength is one at which the saturated initiator is more sensitive than the α-cleaving group. For example, a composition comprising PIA #2 (which has an absorption spectrum with an absorption maximum at a wavelength of about 300 nm) as the C monomer and 2,2-dimethoxy-2-phenyl-l- phenylethanone (which is activated by radiation having a wavelength maximum at about 350 nm) as the saturated initiator.
Extent of polymerization can be monitored by measuring the refractive index of the adhesive layer. Refractive index is a sensitive measure of the extent of polymerization. This method is commonly applied in polymerization kinetics work. See, for example, discussions about the method in Polymerization at Advanced Degrees of Conversion, G.P. Gladyshev and K M. Gibov, Keter Press, Jerusalem (1970). Change in refractive index occurs linearly with conversion of (meth)acrylate unsaturation.
Where the crosslinked viscoelastomeric material of the present invention is a PSA, it displays balanced PSA properties (i.e., a good combination of adhesion, cohesion, stretchiness, and elasticity). This is believed to result from the crosslinked nature of the viscoelastomeric material. Crosslinking in the present invention is quite different from the conventional mechanism of crosslinking provided by diacrylates where a similar increase in concentration of diacrylates results in a concomitant reduction in peel adhesion strength without an increase in static shear strength.
A multilayered tape that includes at least one cured layer derived from the syrup of the present invention is also within the scope of the present invention. Such tapes can have a thin layer of a different PSA laminated thereto, so that the adhesive of the invention is being used as a backing or core layer. The additional layer(s) can be any conventional adhesive known in the art; however,
(meth)acrylic adhesives are preferred. Such multilayered constructions can be
n ; r - . _..
-0) prepared by processes disclosed in U.S. Patent Nos. 4,818,610, 4,894,259, and 4,895,738, the teachings of which are incorporated herein by reference. More preferably, additional adhesive layers include polymers of at least one alkyl (meth)acrylate monomer and a copolymerizable monomer hompolymerizable to a polymer with a T above about 50°C.
Multilayered tapes where a layer of a polyurethane, polychloroprene, polyacrylic foam, or polyethylene foam on which is coated a layer of the viscoelastomeric material of the present invention are also possible. Such tapes are often used to attain very high bond strengths. Further information about such constructions can be found in, for example, U.S. Patent Nos. 3,565,247,
3,993,833, and 4,415,615, the teachings of which are incorporated herein by reference.
When the coated films of the present invention are cured, they preferably have a percent gel (corrected for any soluble tackifying resins and other additives) in the range of from 2 to 95% (by wt ), more preferably from 30 to 90% (by wt.), and most preferably from 50 to 80% (by wt.).
The compositions of the present invention can also be used to make a cellular PSA membrane as is described in U.S. Patent No. 4,415,615, the teaching of which is incorporated herein by reference. Objects and advantages of this invention are further illustrated by the following examples. The particular materials and amounts thereof, as well as other conditions and details, recited in these examples should not be used to unduly limit this invention.
EXAMPLES
A. Static Shear Value
The adhesive films described in the examples were cut into strips 1.27 cm in width. One of the release liners was removed and the strip was placed, with the adhesive side down, onto a piece of aluminum foil 125 μm thick and 1.6 cm wide. The remaining release liner film was removed from each of the strips to form a
"test adhesive tape" and adhered by its adhesive to a flat, rigid stainless steel plate with exactly 1.27 cm length of tape in contact with the plate. Before testing, a 1000 g weight at 25°C was placed over the bonded area for about 15 minutes. The plate with the adhered tape was placed either at room temperature (RT) or in an air-circulating oven which had been preheated to 70°C. A weight was hung from the free end of the tape, with the panel tilted 2° from vertical to eliminate any peel forces. The time (in minutes) at which the weight fell was designated the static shear RT (1000 g) or 70°C (500 g). The test was discontinued after 10,000 minutes if no failure occurred and the result given as "10,000+".
B. Peel Strength
Each measurement was made using a 90° peel mode at 30.5 cm/ in. In the Examples below, results are reported in N/dm.
Pieces of stainless steel were washed once with acetone and three times with a 50:50 water-isopropanol solution. Each adhesive film was adhered to a stainless steel backing for three days prior to being tested. Each sample was about 1.3 cm wide and had a 0.13 mm anodized aluminum backing (about 1.6 cm wide).
Examples 1-5 A number of compositions including the following components were prepared: 90 pbw isooctyl acrylate (prepared according to processes available in the literature) 10 pbw acrylic acid 0.04 pbw 2,2-dimethoxy-2-phenyl-l-phenylethanone (Ciba Geigy).
To each mixture was added the amount of PIA #2 (available as ZLI 3331 from Ciba-Geigy), shown in Table II. Each mixture was degassed in a vacuum desiccator. The degassed mixture was partially polymerized by exposure for about 10 seconds to Sylvania™ F15T8/350 BL 15-watt fluorescent black lamps. The resulting syrup was knife coated onto a 50 μm biaxially-oriented poly( ethylene terephthalate) (PET) film at a thickness of 125 mm for Examples 1 to 5. The coated films were passed through a coating device maintained under N2. The films were exposed to radiation from black lamps having a peak output at 350
2 n and an intensity of 4.0 mW/cm . Each coated tape was aged 72 hours at 25°C and 50% relative humidity. Measured peel adhesion and shear strengths and are listed in Table II.
Table II
Peel Adhesion (N/dm) Shear Strength (min) 1
Ex. Wt. % Stainless Polypropylene 25°C, 70°C,
No. PIA #2 Steel 1 kg load 0.5 kg load
1 0.0 181.5 71.5 366 366
2 0.1 163.3 71.8 612 34
3 0.2 185.7 52.8 7440 199
4 0.3 177.3 58.9 10,000+ 5399
5 0.4 154.5 57.5 10,000+ 10,000+
Those skilled in the art will readily observe that the concentration of C monomer (i.e., PIA #2) over the range from 0 to 0.4% (by wt.) has very little effect on the peel adhesion of the tapes (i.e., the peel adhesion remained within 154 to 186 N/dm for stainless steel and 52 to 72 N/dm for polypropylene). A concentration of C monomer of 0.2% (by wt.) or more in the adhesive is helpful in obtaining shear strengths of more than 5000 minutes at room temperature, and 0.3%) (by wt.) or more is helpful in obtaining shear strengths of more than 5000 minutes at 70°C.
Examples 6-9 Syrups were prepared as described in Examples 1 to 5 using mixtures of monomers as shown in Table III. (In Example 9, the monomer mixture also included a polystyrene macromer with a number average molecular weight of about 13,000.) The weight percentage of 2,2-dimethoxy-2-phenyl-l- phenylethanone and PIA #2 used in each syrup was 0.04%.
SU The syrups of Examples 6 and 7 were coated at a thickness of 250 μm and those of Examples 8 and 9 at 125 μm. A 25 μm thick release-coated sheet of PET was laminated to the syrup-coated side of each tape, and the laminate exposed to radiation as described in Examples 1 to 5. Each PSA tape was then aged for 72 hours at 25°C and a relative humidity of 50%. The peel adhesion and shear strength of each is shown in Table III.
Table III
Amounts of monomer Peel Adhesion (N/dm) Shear Strength (min), (pbw) 25 mm x 125 mm
Ex. IOA AA Poly¬ Stainless Poly(acrylo- 25°C, 1 kg 70°C, 0.5
No. styrene steel nitrilebutadiene- load kg load stvrene)
6 95 5 0 65.5 133.0 10,000+ 10,000+
7 90 10 0 177.4 142.1 10,000+ 10,000+
8 80 20 0 131.2 45.9 10,000+ 10,000+
9 90 10 4 139.7 59.9 10,000+ 10,000+
Example 10
To a series of glass jars purged with nitrogen were added 90 pbw IOA, 10 pbw AA, 0.04 pph 2,2-dimethoxy-2-phenyl-l-phenylethanone, and varying amounts of PIA #2. Each mixture was exposed to low intensity UV radiation so as to partially polymerize the monomers to a coatable viscosity. An additional 0.16 pph 2,2-dimethoxy-2-phenyl-l-phenylethanone was added after the syrup was made. Varying amounts of HDD A were also added to the syrup.
The mixtures were cured on a solvent-free silicone paper release liner at a thickness of 0.13 mm. The samples were exposed to low intensity radiation for 145 seconds, the first third of the time at an intensity of 1.9 mW/cm2 and the remainder of the time at an intensity of 4.2 mW/cm2. The oxygen level was 250 ± 20 ppm. The samples were exposed to high intensity radiation at an average intensity of 112 mW/cm2 for about five seconds. The conversion of all the polymers was greater than 98%. Peel strength values were determined after the peel samples were adhered to the stainless steel substrates for three days.
Static shear strength values were measured using stainless steel substrates cleaned once with acetone and three times with a 50:50 isopropanol/water mixture. 2.54 cm x 1.27 cm samples were prepared and a 1000 g load was used at room temperature and a 500 g load was used at 70°C. The shear samples were adhered to stainless steel for four hours prior to hanging. (0.13 mm anodized aluminum backings were used for all of the samples.) The time until failure is the average of two samples (in minutes).
Table IV
Ex. Amt. of Amt. of Shear Strength (min) Peel
No. PIA (pph) HDDA (pph) Strength (N/dm) RT 70°C
CI 0 0.1 10,000+ 141 203
C2 0.028 0.05 10,000+ 265 200
10 0.125 0.05 10,000+ 10,000+ 196
Example CI shows that, when using HDDA by itself, balanced properties (i.e., a PSA with high room temperature shear, high 70°C shear, and high peel strength) are not obtained. Example C2 shows that too low of a loading level of PIA, when used with HDDA, also does not provide balanced static shear strength properties. However, at loading levels of about 0.1 pph of PIA used in combination with high intensity radiation and about 0.05 pph HDDA, balanced shear properties can be achieved. Various modifications and alterations that do not depart from the scope and spirit of this invention will become apparent to those skilled in the art. This invention is not to be unduly limited to the illustrative embodiments set forth therein.

Claims

We claim:
1. A syrup curable to a crosslinked viscoelastomeric material comprising: a) about 85 to 99.9 weight percent of a solvent monomer mixture comprising
1) 95 to 100 parts by weight of at least one free radically- polymerizable ethylenically unsaturated monomer, and
2) 0 to 5 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group; b) about 0.1 to 15 weight percent of a solute polymer comprising
1) 95 to 100 weight percent mer units derived from one or more free radically-polymerizable ethylenically unsaturated monomers, and 2) 0 to 5 weight percent mer units derived from an ethylenically- unsaturated monomer comprising a radiation-sensitive α- cleaving group; with the proviso that the weight percent of the second component of said polymer cannot be zero when said monomer mixture comprises zero parts by weight of said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group; c) from 0 to 5 parts by weight of a free radically-polymerizable polyethylenically unsaturated monomer; and d) from 0 to 3 parts by weight of a saturated energy-activated initiator of polymerization.
2. The syrup of claim 1 wherein said at least one free radically- polymerizable ethylenically unsaturated monomer of said monomer mixture comprises a monoethylenically unsaturated monomer homopolymerizable to a polymer having a glass transition temperature of less than about 0°C.
SUES ITUT. c bn (R LE 26)
3. The syrup of claim 2 wherein said (meth)acrylic acid ester is selected from the group consisting of isooctyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, decyl acrylate, dodecyl acrylate, hexyl acrylate, and butyl acrylate.
4. The syrup of claim 2 wherein said at least one free radically- polymerizable ethylenically unsaturated monomer further comprises a monoethylenically unsaturated monomer homopolymerizable to a polymer having a glass transition temperature of greater than about 50°C.
5. The syrup of claim 4 wherein said second monoethylenically unsaturated monomer is selected from the group consisting of (meth)acrylic acid, itaconic acid, N,N-dimethylacrylamide, N-octylacrylamide, 2-hydroxyethyl acrylate, N-vinyl pyrrolidone, N-vinyl caprolactam, acrylonitrile, tetrahydrofurfuryl acrylate, and isobornyl acrylate.
6. The syaip of claim 1 wherein said ethylenically unsaturated monomer comprising a radiation-sensitive group has the formula
Figure imgf000029_0001
wherein
R is H or a Ci to C3 alkyl group, preferably H or a methyl group;
X is O or NH, n is 0 or 1; m is 0 or an integer from 1 to 5; a, b, and c are independently 0 or 1 ;
M1 is CH2 or SiR'R2;
M2 is CR3R4 or SiR^2,
M3 is O, NH, C(O), C(O)O, C(O)NH, or OC(O)NH;
SUBSTITUTE SHEET (RULE 2o) R1 and R2 are independently H or a Ci to C4 alkyl group;
RJ and R4 are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyi group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic O heteroatoms, or R3 and R4 taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;
G is a covalent bond, (CH2)_, or (CH2)_O where d is an integer from 1 to 4, preferably from 1 to 2;
Z is a radiation-sensitive α-cleaving group having the formula
Figure imgf000030_0001
in which
Ar is a substituted arene having 6 to 12 carbon atoms;
R is hydrogen, a { to CJ2 alkyl group, a Cl to C12 alkoxy group, or a phenyl group, and
9 R is selected from the group consisting of
Figure imgf000030_0002
in which R is selected from the class consisting of hydrogen, C, to C12 alkyl groups, C, to C,2 alkoxy groups, and phenyl groups, with the proviso that, when R and R are both ortho to the carbonyl group of Z, together they can be one of
SUBSTITUTE SHEET (PULE j?^ O
II
— O- -C- -S — and -CH2-
and
6 7 8
R , R , and R are independently selected from the class consisting of hydroxyl, phenyl, Cj to C6 alkyl, Cj to C6 alkoxy, and
10 11 10 11
— NR R groups, wherein R and R are independently hydrogen or a Cχ to C6 alkyl group,
9 6 7 8 with the proviso that, when R is — CR R R , one of the following must be true:
6 7 8
(1) at least one of R , R , and R is selected from the class
10 11 consisting of hydroxyl, alkoxy, and — NR R ;
6 7 8
(2) any two of R , R , and R together are one of — C H_ — and
— OC H2 O — wherein p is either 2 or 3 so that they, together with the carbon atoms to which they are attached, form a 5- or 6-membered ring; and
6 7 8
(3) any two of R , R , and R together are a carbonyl group,
6 7 8 provided that the remaining one of R , R , and R is selected
10_ 11 from the class consisting of hydroxy, alkoxy, — NR R , and phenyl groups.
9
7. The syrup of claim 6 wherein R of said ethylenically unsaturated monomer comprising a radiation-sensitive group is
R6
I 7 — C-R7
' _ R8
8. The syrup of claim 6 wherein X is O, m is 0, and G is (CH2)_O with d being 2.
SUBSTITUTE SHZET (M:L E 2-"!)
9. The syrup of claim 6 wherein Ar of said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group is a benzene group.
10. The syrup of claim 1 wherein said saturated energy-activated initiator of polymerization is present in an amount of 0.001 to 1.0 parts by weight.
1 1. The syrup of claim 10 wherein said energy is ultraviolet radiation.
12. The syrup of claim 1 wherein said syrup is of a coatable viscosity.
13. A process for making a viscoelastomeric material comprising the steps: a) providing a composition comprising
1) a solvent monomer mixture comprising (a) at least one free radically-polymerizable ethylenically unsaturated monomer, and (b) 0 to 5 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive group, and
2) 0 to 3 parts by weight of a saturated energy-activated initiator of polymerization, with the proviso that the amount of said saturated initiator must be greater than zero when the amount of said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group is zero; b) exposing said composition to energy so as to partially polymerize said monomer mixture to form a coatable syrup; c) adding to said syrup, based on the total amount of monomer initially present in said monomer mixture,
1) 0 to 3 parts by weight of a saturated energy-activated initiator of polymerization, 2) 0 to 3 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group, with the proviso
Sϋb. that the amount of ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group added to said syrup must be greater than zero when the amount of said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group in said monomer mixture is zero, and
3) 0 to 5 parts by weight of a free radically-polymerizable polyethylenically unsaturated monomer; and d) exposing said syrup to energy that activates said saturated initiator and said radiation-sensitive α-cleaving group of said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group so as to form said viscoelastomeric material.
14. The process of claim 13 wherein said ethylenically unsaturated monomer comprising a radiation-sensitive α-cleaving group has the formula
Figure imgf000033_0001
wherein
R is H or a d to Cj alkyl group, preferably H or a methyl group;
X is O or NH; n is 0 or 1; m is 0 or an integer from 1 to 5; a, b, and c are independently 0 or 1;
M1 is CH2 or SiR l'Rτ_ 2;.
M' is CR | 3R or SiR l'Rr> 2,. M3 is O, NH, C(O), C(0)0, C(O)NH, or OC(O)NH; R1 and R2 are independently H or a Ci to C alkyl group; R3 and R4 are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyi group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic O heteroatoms, or R3 and R4 taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;
G is a covalent bond, (CH2)_, or (CH2)_O where d is an integer from 1 to 4, preferably from 1 to 2;
Z is a radiation-sensitive α-cleaving group having the formula
Figure imgf000034_0001
in which
Ar is a substituted arene group having 6 to 12 carbon atoms;
R is hydrogen, a Cχ to C,2 alkyl group, a C, to C12 alkoxy group, or a phenyl group; and
9
R is selected from the group consisting of
Figure imgf000034_0002
in which
R is selected from the class consisting of hydrogen, C to C12 alkyl groups, C} to C]2 alkoxy groups, and phenyl groups, with the
_ 5 proviso that, when R and R are both ortho to the carbonyl group of Z, together they can be one of
— O — — C — — S — and -CH2-
and 6 7 8
R , R , and R are independently selected from the class consisting of hydroxyl, phenyl, Cj to Cfi alkyl, C( to Cfi alkoxy, and
10 11 10 11
— NR R groups, wherein R and R are independently hydrogen or a C{ to C6 alkyl group,
9 6 7 8 with the proviso that, when R is — CR R R , one of the following must be true:
6 7 8
(1) at least one of R , R , and R is selected from the class
10 11 consisting of hydroxyl, alkoxy, and — NR R ;
6 7 8
(2) any two of R , R , and R together are one of — C Y^ — and — OC H2 O — wherein p is either 2 or 3 so that they, together with the carbon atoms to which they are attached, form a 5- or 6-membered ring; and
6 7 8
(3) any two of R , R , and R together are a carbonyl group,
6 7 8 provided that the remaining one of R , R , and R is selected from the class
10 11 consisting of hydroxy, alkoxy, — NR R , and phenyl groups.
15. The process of claim 14 further comprising the step: e) prior to irradiating said syrup, coating said syrup on a substrate.
16. The process of claim 15 wherein said substrate is a flexible web.
SU3STITUTI L_ 2_)
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EP95928204A EP0772655B1 (en) 1994-07-29 1995-07-28 Acrylic syrup curable to a crosslinked viscoelastomeric material
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5879759A (en) * 1997-12-22 1999-03-09 Adhesives Research, Inc. Two-step method for the production of pressure sensitive adhesive by radiation curing
WO2015164087A1 (en) * 2014-04-24 2015-10-29 3M Innovative Properties Company Compositions comprising cleavable crosslinker and methods
US9254262B2 (en) 2008-03-13 2016-02-09 Almirall, S.A. Dosage and formulation
US9333195B2 (en) 1999-07-14 2016-05-10 Almirall, S.A. Quinuclidine derivatives and medicinal compositions containing the same
US9737520B2 (en) 2011-04-15 2017-08-22 Almirall, S.A. Aclidinium for use in improving the quality of sleep in respiratory patients
US10085974B2 (en) 2008-03-13 2018-10-02 Almirall, S.A. Dosage and formulation

Families Citing this family (141)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5538774A (en) * 1994-07-29 1996-07-23 Minnesota Mining And Manufacturing Company Internally damped rotatable storage article
US5773485A (en) 1994-07-29 1998-06-30 Minnesota Mining And Manufacturing Company Acrylic syrup curable to a crosslinked viscoelastomeric material
EP0837844B1 (en) * 1995-07-28 2000-04-05 Minnesota Mining And Manufacturing Company Acrylamide derivatives as chromophoric photocrosslinking compound
DE19653631A1 (en) * 1996-12-20 1998-06-25 Basf Coatings Ag Process for producing radiation-crosslinkable polymeric acrylic or methacrylic acid esters
US6628040B2 (en) * 2000-02-23 2003-09-30 Sri International Electroactive polymer thermal electric generators
US7320457B2 (en) * 1997-02-07 2008-01-22 Sri International Electroactive polymer devices for controlling fluid flow
US6376971B1 (en) 1997-02-07 2002-04-23 Sri International Electroactive polymer electrodes
US6812624B1 (en) * 1999-07-20 2004-11-02 Sri International Electroactive polymers
US6781284B1 (en) 1997-02-07 2004-08-24 Sri International Electroactive polymer transducers and actuators
US6545384B1 (en) 1997-02-07 2003-04-08 Sri International Electroactive polymer devices
CN1121421C (en) * 1997-02-19 2003-09-17 西巴特殊化学品控股有限公司 (CO) polymers by photopolymerization
US6599602B2 (en) 1999-06-02 2003-07-29 3M Innovative Properties Company Polycarbonate articles and adhesive composition therefor
US7537197B2 (en) * 1999-07-20 2009-05-26 Sri International Electroactive polymer devices for controlling fluid flow
DE60037433T2 (en) * 1999-07-20 2008-12-04 Sri International, Menlo Park Electroactive polymer generators
US6448337B1 (en) 1999-10-07 2002-09-10 3M Innovative Properties Company Pressure sensitive adhesives possessing high load bearing capability
US6340719B1 (en) 1999-12-29 2002-01-22 3M-Innovative Properties Company Crosslinking process
US6911764B2 (en) 2000-02-09 2005-06-28 Sri International Energy efficient electroactive polymers and electroactive polymer devices
EP1259992B1 (en) * 2000-02-23 2011-10-05 SRI International Biologically powered electroactive polymer generators
DE10008842C1 (en) * 2000-02-25 2001-06-28 Beiersdorf Ag Method of reducing flow viscosity of polyacrylate composition, used as adhesive, involves mixing (co)polyacrylate(s) with (co)polyacrylate(s) with lower molecular weight and ultraviolet-curable functional groups
US20020004130A1 (en) * 2000-07-07 2002-01-10 Ramesh Lhila Acrylic foam-like tape
US6841234B2 (en) 2000-08-04 2005-01-11 Scapa Tapes North America Inc. Heat-activated adhesive tape having an acrylic foam-like backing
US6448301B1 (en) 2000-09-08 2002-09-10 3M Innovative Properties Company Crosslinkable polymeric compositions and use thereof
US6709716B2 (en) 2001-04-27 2004-03-23 3M Innovative Properties Company Microemulsion compositions and methods of making and using same
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DE10295498D2 (en) * 2001-11-24 2004-11-11 Tesa Ag 2-component crosslinking of end-functionalized polyacrylates
EP2317639A1 (en) * 2002-03-18 2011-05-04 SRI International Electroactive polymer devices for moving fluid
US7157535B2 (en) * 2002-06-19 2007-01-02 National Starch And Chemical Investment Holding Corporation Polymeric photoinitiators
AU2002953099A0 (en) * 2002-12-04 2002-12-19 Australian Composites Pty Ltd Reinforced polymer composition
US7927703B2 (en) * 2003-04-11 2011-04-19 3M Innovative Properties Company Adhesive blends, articles, and methods
WO2004101678A1 (en) 2003-05-19 2004-11-25 Nippon Shokubai Co., Ltd. Resin composition for thermally conductive material and thermally conductive material
WO2005007819A2 (en) 2003-07-09 2005-01-27 Wisconsin Alumni Research Foundation Charge-dynamic polymers and delivery of anionic compounds
US20050070688A1 (en) * 2003-09-26 2005-03-31 3M Innovative Properties Company Reactive hydrophilic oligomers
US7691437B2 (en) * 2003-10-31 2010-04-06 3M Innovative Properties Company Method for preparing a pressure-sensitive adhesive
US7384984B2 (en) * 2003-12-10 2008-06-10 3M Innovative Properties Company Reactive hydrophilic oligomers
US7074839B2 (en) * 2004-03-01 2006-07-11 3M Innovative Properties Company Crosslinkable hydrophilic materials from reactive oligomers having pendent photoinitiator groups
US7342047B2 (en) * 2004-03-02 2008-03-11 3M Innovative Properties Company Crosslinkable hydrophilic materials from reactive oligomers having pendent unsaturated groups
JP4543140B2 (en) * 2004-08-16 2010-09-15 綜研化学株式会社 Circuit board protecting adhesive sheet and method for producing the same
US7332546B2 (en) * 2004-10-01 2008-02-19 3M Innovative Properties Company Ring-opened azlactone telechelic polymer
US7304112B2 (en) * 2004-10-01 2007-12-04 3M Innovative Properties Company Azlactone telechelic polymer
US7307106B2 (en) * 2004-12-10 2007-12-11 3M Innovative Properties Company Photocurable Michael addition polymers
US20060234014A1 (en) * 2005-04-14 2006-10-19 Liu Yaoqi J Patterned adhesives for tamper evident feature
US20060234040A1 (en) * 2005-04-14 2006-10-19 Liu Yaoqi J Patterned adhesives for color shifting effect
US7981988B2 (en) * 2006-05-25 2011-07-19 3M Innovative Properties Company Ultraviolet radiation-polymerizable compositions
US8834918B2 (en) * 2007-01-22 2014-09-16 Wisconsin Alumni Research Foundation Modified multilayered film
WO2009006318A1 (en) 2007-06-29 2009-01-08 Artificial Muscle, Inc. Electroactive polymer transducers for sensory feedback applications
US7842762B2 (en) * 2007-08-08 2010-11-30 Ppg Industries Ohio, Inc. Electrodepositable coating composition containing a cyclic guanidine
WO2009049092A1 (en) * 2007-10-09 2009-04-16 Wisconsin Alumni Research Foundation Covalent assembly of ultrathin polymeric films
US20090098359A1 (en) 2007-10-11 2009-04-16 Waller Jr Clinton P Hydrophilic porous substrates
US7652103B2 (en) * 2008-02-14 2010-01-26 3M Innovative Properties Company Acrylic pressure-sensitive adhesives with aziridine crosslinking agents
US7714076B2 (en) * 2008-03-27 2010-05-11 3M Innovative Properties Company Acrylic pressure-sensitive adhesives with aziridine crosslinking agents
EP2294118B1 (en) * 2008-05-30 2012-07-04 3M Innovative Properties Company Method of making ligand functionalized substrates
JP2011523965A (en) 2008-05-30 2011-08-25 スリーエム イノベイティブ プロパティズ カンパニー Ligand functionalized substrate
EP2291478B1 (en) * 2008-06-09 2012-08-01 3M Innovative Properties Company Acrylic pressure-sensitive adhesives with aziridine crosslinking agents
WO2010033807A1 (en) * 2008-09-19 2010-03-25 3M Innovative Properties Company Ligand graft functionalized substrates
US8765217B2 (en) 2008-11-04 2014-07-01 Entrotech, Inc. Method for continuous production of (meth)acrylate syrup and adhesives therefrom
US7838110B2 (en) * 2008-12-02 2010-11-23 3M Innovative Properties Company Aziridine-functional photoactive crosslinking compounds
JP5595413B2 (en) * 2008-12-12 2014-09-24 ビーエーエスエフ ソシエタス・ヨーロピア Modified polyvinyl lactam
WO2010077435A1 (en) * 2008-12-31 2010-07-08 3M Innovative Properties Company Stretch releasable pressure-sensitive adhesives
EP2406338B1 (en) 2009-03-09 2012-11-28 3M Innovative Properties Company Aziridine crosslinking agents for acrylic adhesives
EP2239793A1 (en) 2009-04-11 2010-10-13 Bayer MaterialScience AG Electrically switchable polymer film structure and use thereof
US8329079B2 (en) 2009-04-20 2012-12-11 Entrochem, Inc. Method and apparatus for continuous production of partially polymerized compositions and polymers therefrom
BRPI1011747A2 (en) 2009-06-23 2018-02-27 3M Innovative Properties Co functionalized nonwoven article.
US8067504B2 (en) 2009-08-25 2011-11-29 3M Innovative Properties Company Acrylic pressure-sensitive adhesives with acylaziridine crosslinking agents
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CN102108133B (en) * 2009-12-23 2014-12-10 3M创新有限公司 (Methyl) acrylyl-aziridine crosslinking agent and adhesive polymer
CN102127183B (en) 2010-01-20 2014-08-20 3M创新有限公司 Crosslinkable acrylate adhesive polymer composite
US8712559B2 (en) * 2010-02-10 2014-04-29 The Board Of Trustees Of The University Of Illionois Adaptive control for uncertain nonlinear multi-input multi-output systems
US8377672B2 (en) 2010-02-18 2013-02-19 3M Innovative Properties Company Ligand functionalized polymers
EP2889625B1 (en) 2010-03-03 2016-09-14 3M Innovative Properties Company Ligand guanidinyl functionalized polymers
US8222340B2 (en) 2010-04-05 2012-07-17 3M Innovative Properties Company Crosslinkable syrup copolymers with aminoalkyl (meth)acryloyl solvent monomers
WO2012077720A1 (en) * 2010-12-09 2012-06-14 協立化学産業株式会社 Compound suitable for photopolymerization initiator, photopolymerization initiator, and photocurable resin composition
CN103282429B (en) 2010-12-29 2015-11-25 3M创新有限公司 There is the pressure sensitive adhesive of triazine-epoxy cross-linking system
US8563560B2 (en) 2011-02-25 2013-10-22 Ppg Industries Ohio, Inc. Preparation of bicyclic guanidine salts in an aqueous media
EP2681748B1 (en) 2011-03-01 2016-06-08 Parker-Hannifin Corp Automated manufacturing processes for producing deformable polymer devices and films
US9195058B2 (en) 2011-03-22 2015-11-24 Parker-Hannifin Corporation Electroactive polymer actuator lenticular system
US8785517B2 (en) 2011-05-25 2014-07-22 3M Innovative Properties Company Pressure-sensitive adhesives with onium-epdxy crosslinking system
US8871827B2 (en) * 2011-06-07 2014-10-28 Basf Se Hotmelt adhesive comprising radiation-crosslinkable poly(meth)acrylate and oligo(meth)acrylate with nonacrylic C-C double bonds
WO2012177337A1 (en) 2011-06-23 2012-12-27 3M Innovative Properties Company Pressure-sensitive adhesives with onium-epoxy resin crosslinking system
WO2013052105A2 (en) 2011-10-03 2013-04-11 Biomimedica, Inc. Polymeric adhesive for anchoring compliant materials to another surface
US9876160B2 (en) 2012-03-21 2018-01-23 Parker-Hannifin Corporation Roll-to-roll manufacturing processes for producing self-healing electroactive polymer devices
US8715904B2 (en) * 2012-04-27 2014-05-06 3M Innovative Properties Company Photocurable composition
WO2013192143A1 (en) 2012-06-18 2013-12-27 Bayer Intellectual Property Gmbh Stretch frame for stretching process
CN104737018B (en) 2012-09-27 2017-06-30 3M创新有限公司 Part graft base
WO2014066576A1 (en) 2012-10-24 2014-05-01 Bayer Intellectual Property Gmbh Polymer diode
EP2970725A1 (en) 2013-03-13 2016-01-20 3M Innovative Properties Company Adhesives comprising epoxy-acid crosslinked groups and methods
US9068089B2 (en) 2013-03-15 2015-06-30 Ppg Industries Ohio, Inc. Phenolic admix for electrodepositable coating composition containing a cyclic guanidine
JP2016521306A (en) 2013-04-15 2016-07-21 スリーエム イノベイティブ プロパティズ カンパニー Adhesive and method comprising a crosslinking agent having a (meth) acrylate group and an olefin group
US9688874B2 (en) 2013-10-25 2017-06-27 Ppg Industries Ohio, Inc. Method of making a bicyclic guanidine-cured acrylic coating
EP2878606B1 (en) * 2013-11-29 2015-08-05 ICAP-SIRA S.p.A. UV-curable composition and pressure sensitive adhesive having breathability derived therefrom, as well as method for manufacturing the same
CN105814155A (en) 2013-12-09 2016-07-27 3M创新有限公司 Curable silsesquioxane polymers, compositions, articles, and methods
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JP2017519081A (en) 2014-06-20 2017-07-13 スリーエム イノベイティブ プロパティズ カンパニー Curable polymer and method comprising a silsesquioxane polymer core and a silsesquioxane polymer outer layer
WO2016036634A1 (en) 2014-09-02 2016-03-10 3M Innovative Properties Company Acrylate adhesive with vinylsilane crosslinking agents
CN106715495A (en) 2014-09-12 2017-05-24 3M创新有限公司 Allyl acrylate crosslinkers for PSAs
US9957358B2 (en) 2014-09-22 2018-05-01 3M Innovative Properties Company Curable polymers comprising silsesquioxane polymer core silsesquioxane polymer outer layer, and reactive groups
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CN107001862A (en) 2014-12-05 2017-08-01 3M创新有限公司 Slurry polymerisation compositions and by its obtained adhesive
CN107108922B (en) 2014-12-08 2020-08-18 3M创新有限公司 Acrylic polyvinyl acetal films and compositions
CN107001761B (en) 2014-12-08 2020-06-16 3M创新有限公司 Acrylic polyvinyl acetal film, composition, and heat-bondable article
EP3298098A1 (en) 2015-05-18 2018-03-28 3M Innovative Properties Company Pressure sensitive adhesive comprising (meth)acrylic polymer comprising epoxy-functional groups and triazine crosslinker
US10350861B2 (en) * 2015-07-31 2019-07-16 Corning Incorporated Laminate structures with enhanced damping properties
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CN114929776A (en) 2019-12-20 2022-08-19 3M创新有限公司 Adhesive articles, adhesive compositions, and methods comprising polymer and polymerizable cyclic olefin
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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993020164A1 (en) * 1992-03-31 1993-10-14 Minnesota Mining And Manufacturing Company Ultraviolet radiation curable acrylate pressure-sensitive adhesive compositions

Family Cites Families (68)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE24906E (en) * 1955-11-18 1960-12-13 Pressure-sensitive adhesive sheet material
DE1184034B (en) * 1963-03-13 1964-12-23 Hoechst Ag Process for dry cleaning of fiber material
FR1432713A (en) * 1965-02-10 1966-03-25 Novacel Sa New manufacturing process for pressure-adhering adhesive tapes and device therefor
US3615972A (en) * 1967-04-28 1971-10-26 Dow Chemical Co Expansible thermoplastic polymer particles containing volatile fluid foaming agent and method of foaming the same
US3575925A (en) * 1968-06-17 1971-04-20 Nat Starch Chem Corp Photosensitive coating systems
US3565247A (en) * 1968-10-21 1971-02-23 Minnesota Mining & Mfg Pressure-sensitive adhesive tape product
US4075238A (en) * 1973-10-29 1978-02-21 Hooker Chemicals & Plastics Corporation Polyhalobenzylic disulfooxonium compounds
US4181752A (en) * 1974-09-03 1980-01-01 Minnesota Mining And Manufacturing Company Acrylic-type pressure sensitive adhesives by means of ultraviolet radiation curing
DE2443414C2 (en) * 1974-09-11 1983-05-19 Beiersdorf Ag, 2000 Hamburg Process for the manufacture of self-adhesive products
US3993833A (en) * 1976-01-19 1976-11-23 Minnesota Mining And Manufacturing Company Polyurethane foam-backed pressure-sensitive adhesive tape
US4223067A (en) * 1978-03-27 1980-09-16 Minnesota Mining And Manufacturing Company Foam-like pressure-sensitive adhesive tape
US4181755A (en) * 1978-11-21 1980-01-01 Rca Corporation Thin film pattern generation by an inverse self-lifting technique
US4243500A (en) * 1978-12-04 1981-01-06 International Coatings, Co., Inc. Pressure sensitive adhesives
US4303485A (en) * 1979-08-20 1981-12-01 Minnesota Mining And Manufacturing Company Ultraviolet polymerization of acrylate monomers using oxidizable tin compounds
US4304705A (en) 1980-01-02 1981-12-08 Minnesota Mining And Manufacturing Company Radiation-curable polymers containing pendant unsaturated peptide groups derived from azlactone polymers
US4329384A (en) * 1980-02-14 1982-05-11 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive tape produced from photoactive mixture of acrylic monomers and polynuclear-chromophore-substituted halomethyl-2-triazine
US4330590A (en) * 1980-02-14 1982-05-18 Minnesota Mining And Manufacturing Company Photoactive mixture of acrylic monomers and chromophore-substituted halomethyl-2-triazine
US4391687A (en) * 1980-02-14 1983-07-05 Minnesota Mining And Manufacturing Company Photoactive mixture of acrylic monomers and chromophore-substituted halomethyl-1-triazine
JPS6021770B2 (en) * 1980-02-14 1985-05-29 松本油脂製薬株式会社 Method for manufacturing thermally expandable microcapsules
JPS5846236B2 (en) * 1980-03-05 1983-10-14 日東電工株式会社 pressure sensitive adhesive composition
US4364972A (en) * 1981-01-16 1982-12-21 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive copolymers of acrylic acid ester and N-vinyl pyrrolidone
US4379201A (en) * 1981-03-30 1983-04-05 Minnesota Mining And Manufacturing Company Multiacrylate cross-linking agents in pressure-sensitive photoadhesives
JPS5846236A (en) * 1981-09-16 1983-03-17 Clarion Co Ltd Clutch
US4777276A (en) 1981-10-29 1988-10-11 Minnesota Mining And Manufacturing Company Acrylamidoacylated oligomers
GB2108487B (en) 1981-11-03 1985-07-31 Sericol Group Ltd Water soluble thioxanthone photoinitiators
US4415615A (en) * 1982-01-15 1983-11-15 Minnesota Mining And Manufacturing Co. Cellular pressure-sensitive adhesive product and method of making
JPS6183273A (en) * 1984-09-28 1986-04-26 Nitto Electric Ind Co Ltd Photo-setting self-adhesive molding
US4710536A (en) * 1985-08-07 1987-12-01 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive tape containing hydrophobic silica
US4749590A (en) * 1985-08-07 1988-06-07 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive tape containing hydrophobic silica
DE3534645A1 (en) * 1985-09-28 1987-04-02 Merck Patent Gmbh COPOLYMERIZABLE PHOTOINITIATORS
US4732808A (en) * 1985-11-14 1988-03-22 Minnesota Mining And Manufacturing Company Macromer reinforced pressure sensitive skin adhesive sheet material
US4737559A (en) * 1986-05-19 1988-04-12 Minnesota Mining And Manufacturing Co. Pressure-sensitive adhesive crosslinked by copolymerizable aromatic ketone monomers
US4818610A (en) * 1986-08-29 1989-04-04 Minnesota Mining And Manufacturing Company Unified pressure-sensitive adhesive tape
US4894259A (en) * 1986-08-29 1990-01-16 Minnesota Mining And Manufacturing Company Process of making a unified pressure-sensitive adhesive tape
US4895738A (en) * 1986-08-29 1990-01-23 Minnesota Mining And Manufacturing Company Method of making a unified pressure-sensitive adhesive tape
EP0258719A3 (en) * 1986-08-30 1989-07-05 Ciba-Geigy Ag Two-layer system
DE3738567A1 (en) * 1987-03-12 1988-09-22 Merck Patent Gmbh COREACTIVE PHOTOINITIATORS
DE3880920T2 (en) * 1987-08-05 1993-10-07 Ciba Geigy Links.
US4874822A (en) 1988-04-07 1989-10-17 Minnesota Mining And Manufacturing Company Process for the acrylamidoacylation of alcohols
US5264533A (en) * 1988-06-16 1993-11-23 Basf Aktiengesellschaft Benzophenone derivatives and their preparation
JPH089586B2 (en) * 1988-09-28 1996-01-31 昭和電工株式会社 Bifunctional acrylate compound and method for producing the same
DE3836968A1 (en) * 1988-10-31 1990-05-03 Basf Ag UV CROSSLINKABLE MASSES BASED ON ISOAMYL (METH) ACRYLATE COPOLYMERISATS
US4931582A (en) 1988-11-04 1990-06-05 Minnesota Mining And Manufacturing Company Fluorinated, acrylamide-functional monomers
JP2604453B2 (en) * 1988-12-14 1997-04-30 積水化学工業株式会社 Acrylic adhesive tape
DE3844445A1 (en) * 1988-12-31 1990-07-19 Basf Ag UV-CROSSLINKABLE MASSES BASED ON (METH) -ACRYLESTER POLYMERISATS
US5248805A (en) * 1988-12-31 1993-09-28 Basf Aktiengesellschaft Radiation-senstive, ethylenically unsaturated, copolymerizable compounds and their preparation
JP2744051B2 (en) * 1989-03-09 1998-04-28 積水化学工業株式会社 Acrylic adhesive and method for producing acrylic adhesive tape or sheet
JPH02248482A (en) * 1989-03-23 1990-10-04 Fujikura Kasei Co Ltd Photocurable pressure-sensitive adhesive composition
DE3914374A1 (en) * 1989-04-29 1990-10-31 Basf Ag THROUGH ULTRAVIOLET RADIATION UNDER AIR OXYGEN ATMOSPHERIC CROSSLINKABLE COPOLYMERS
DE3914375A1 (en) * 1989-04-29 1990-11-15 Basf Ag THANKS TO ULTRAVIOLET RADIATION
JP2974150B2 (en) * 1989-06-30 1999-11-08 王子製紙株式会社 Adhesive sheet
JP2777219B2 (en) * 1989-09-01 1998-07-16 東陶機器株式会社 Toilet flush water supply
JP2899346B2 (en) * 1990-02-27 1999-06-02 ユニチカ株式会社 Composite material with good laser marking properties
DE4037079A1 (en) 1990-11-22 1992-05-27 Basf Ag UNSATURATED PHENONE DERIVATIVES AND THEIR USE AS ADHESIVE ADHESIVES
AU1641492A (en) * 1991-02-28 1992-10-06 Minnesota Mining And Manufacturing Company Multi-stage irradiation process for production of acrylic based adhesives and adhesives made thereby
WO1993009152A1 (en) * 1991-11-05 1993-05-13 Avery Dennison Corporation Uv-cured hot melt pressure-sensitive adhesives
US5202361A (en) * 1991-12-23 1993-04-13 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive
US5302629A (en) * 1992-05-15 1994-04-12 Berejka Anthony J Hydrophilic acrylic pressure sensitive adhesives
JPH0819392B2 (en) * 1992-11-30 1996-02-28 日東電工株式会社 Pressure-sensitive adhesives and their adhesive sheets
SG49755A1 (en) * 1992-12-07 1998-06-15 Minnesota Mining & Mfg Adhesive for polycarbonate
JPH0819393B2 (en) * 1992-12-09 1996-02-28 日東電工株式会社 Pressure-sensitive adhesives and their adhesive sheets
JP2795366B2 (en) * 1992-12-09 1998-09-10 日東電工株式会社 Adhesive sheets with foam base
DE4243270A1 (en) * 1992-12-21 1994-06-23 Lohmann Gmbh & Co Kg Process for crosslinking pressure sensitive adhesives using lasers
JPH06200225A (en) * 1992-12-29 1994-07-19 Nitto Denko Corp Pressure-sensitive adhesive for coating material and adhesive sheet using the same
DE4303183C1 (en) * 1993-02-04 1994-07-21 Lohmann Gmbh & Co Kg Process for the production of thick pressure-sensitive adhesive layers, in particular for the production of self-adhesive high-performance adhesive articles
US5506279A (en) * 1993-10-13 1996-04-09 Minnesota Mining And Manufacturing Company Acrylamido functional disubstituted acetyl aryl ketone photoinitiators
US5773485A (en) 1994-07-29 1998-06-30 Minnesota Mining And Manufacturing Company Acrylic syrup curable to a crosslinked viscoelastomeric material
WO1997005100A1 (en) 1995-07-28 1997-02-13 Minnesota Mining And Manufacturing Company Chromophoric photocrosslinking compound

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993020164A1 (en) * 1992-03-31 1993-10-14 Minnesota Mining And Manufacturing Company Ultraviolet radiation curable acrylate pressure-sensitive adhesive compositions

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Derwent World Patents Index; *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5879759A (en) * 1997-12-22 1999-03-09 Adhesives Research, Inc. Two-step method for the production of pressure sensitive adhesive by radiation curing
US9333195B2 (en) 1999-07-14 2016-05-10 Almirall, S.A. Quinuclidine derivatives and medicinal compositions containing the same
USRE46417E1 (en) 1999-07-14 2017-05-30 Almirall, S.A. Quinuclidine derivatives and their use as muscarinic M3 receptor ligands
US9687478B2 (en) 1999-07-14 2017-06-27 Almirall, S.A. Quinuclidine derivatives and medicinal compositions containing the same
US10034867B2 (en) 1999-07-14 2018-07-31 Almirall, S.A. Quinuclidine derivatives and medicinal compositions containing the same
US10588895B2 (en) 1999-07-14 2020-03-17 Almirall, S.A. Quinuclidine derivatives and medicinal compositions containing the same
US9254262B2 (en) 2008-03-13 2016-02-09 Almirall, S.A. Dosage and formulation
US10085974B2 (en) 2008-03-13 2018-10-02 Almirall, S.A. Dosage and formulation
US11000517B2 (en) 2008-03-13 2021-05-11 Almirall, S.A. Dosage and formulation
US9737520B2 (en) 2011-04-15 2017-08-22 Almirall, S.A. Aclidinium for use in improving the quality of sleep in respiratory patients
WO2015164087A1 (en) * 2014-04-24 2015-10-29 3M Innovative Properties Company Compositions comprising cleavable crosslinker and methods
US9732173B2 (en) 2014-04-24 2017-08-15 3M Innovative Properties Co. Compositions comprising cleavable crosslinker and methods

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US6245922B1 (en) 2001-06-12
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JP3545414B2 (en) 2004-07-21
JPH10503548A (en) 1998-03-31
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WO1996005249A3 (en) 1996-03-28
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US5773485A (en) 1998-06-30
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US5902836A (en) 1999-05-11
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EP0772655A1 (en) 1997-05-14
ES2142489T3 (en) 2000-04-16
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DE69520434D1 (en) 2001-04-26
WO1996005249A2 (en) 1996-02-22

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