CA1241701A - Self-venting vapor-tight microwave oven package - Google Patents
Self-venting vapor-tight microwave oven packageInfo
- Publication number
- CA1241701A CA1241701A CA000488438A CA488438A CA1241701A CA 1241701 A CA1241701 A CA 1241701A CA 000488438 A CA000488438 A CA 000488438A CA 488438 A CA488438 A CA 488438A CA 1241701 A CA1241701 A CA 1241701A
- Authority
- CA
- Canada
- Prior art keywords
- package
- deposit
- layer
- tape
- particles
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D81/00—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents
- B65D81/34—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within the package
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D81/00—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents
- B65D81/34—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within the package
- B65D81/3446—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within the package specially adapted to be heated by microwaves
- B65D81/3461—Flexible containers, e.g. bags, pouches, envelopes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D2205/00—Venting means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D2581/00—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents
- B65D2581/34—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within
- B65D2581/3437—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within specially adapted to be heated by microwaves
- B65D2581/3439—Means for affecting the heating or cooking properties
- B65D2581/3445—Microwave reactive adhesives, e.g. also used in valves or lids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D2581/00—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents
- B65D2581/34—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within
- B65D2581/3437—Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging foodstuffs or other articles intended to be cooked or heated within specially adapted to be heated by microwaves
- B65D2581/3471—Microwave reactive substances present in the packaging material
- B65D2581/3483—Carbon, carbon black, or graphite
-
- Y—GENERAL 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S229/00—Envelopes, wrappers, and paperboard boxes
- Y10S229/902—Box for prepared or processed food
- Y10S229/903—Ovenable, i.e. disclosed to be placed in an oven
-
- Y—GENERAL 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
-
- Y—GENERAL 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
- Y10T428/2848—Three or more layers
Abstract
Abstract of the Disclosure A vapor-tight package having a deposit comprising nonmetallic, microwave-absorbing particles such as graphite dispersed in nonmetallic binder. When heated in a microwave oven, heat built up in the particles may soften and weaken the underlying packaging material, thus venting the package.
Description
~ 24 17q~ 40177 CAN 4A
--1~
SELF-VENTING VAPOR-TIGHT ~ICROWAVF. OVEN PACKAGE
_ _ Technical Field The invention concerns a vapor-tight package including means automatically venting the package when it i8 heated in a microwave oven.
In~tructions for heating vapor-ti~ht packages in a microwave oven usually call for first piercing each package with a sharp utensil. See, for example, Fig~ 22 of U.S~ Patent No. 4,425,368 (Watkins). Vapor-tight frozen food packages which comprise polymeric or plastic film can be hard to pierCQ~ and one may think that the film has been pierced when it has only been indented. If the film is not pierced, vapor pressures built up during heating may cause the package to explode. Instead of exploding, the package may rip at a seam through which the contents may spill out into the oven.
A number of self-venting, vapor-tight microwave oven packages have been proposed. Each of the packages shown in U~S. Patent No. 4,013,798 (Goltsos) consists of a compartmented plastic tray across which is sealed a plastic film. A side wall of one or more of the compartments has a notch at which the plastic film is less well sealed so that a buildup of vapor pressure in a compartment breaks the seal at the notch to vent the compartment.
U.S. Patent No. 4,292,332 (McHam) concerns a vapor-tight package for popping popcorn in a microwave oven. Its top wall is provided with lines of weakness that will begin to rupture at a vapor pressure less than that which would cause the bag to explode.
U.S. Patent No. 4,141,487 (Faust et al.) concerns a vapor-tight package comprising a plastic film which is formed with a slit along a crease line. The edges of the slit are sealed together by an adhesive sealant ~laterial ,,
--1~
SELF-VENTING VAPOR-TIGHT ~ICROWAVF. OVEN PACKAGE
_ _ Technical Field The invention concerns a vapor-tight package including means automatically venting the package when it i8 heated in a microwave oven.
In~tructions for heating vapor-ti~ht packages in a microwave oven usually call for first piercing each package with a sharp utensil. See, for example, Fig~ 22 of U.S~ Patent No. 4,425,368 (Watkins). Vapor-tight frozen food packages which comprise polymeric or plastic film can be hard to pierCQ~ and one may think that the film has been pierced when it has only been indented. If the film is not pierced, vapor pressures built up during heating may cause the package to explode. Instead of exploding, the package may rip at a seam through which the contents may spill out into the oven.
A number of self-venting, vapor-tight microwave oven packages have been proposed. Each of the packages shown in U~S. Patent No. 4,013,798 (Goltsos) consists of a compartmented plastic tray across which is sealed a plastic film. A side wall of one or more of the compartments has a notch at which the plastic film is less well sealed so that a buildup of vapor pressure in a compartment breaks the seal at the notch to vent the compartment.
U.S. Patent No. 4,292,332 (McHam) concerns a vapor-tight package for popping popcorn in a microwave oven. Its top wall is provided with lines of weakness that will begin to rupture at a vapor pressure less than that which would cause the bag to explode.
U.S. Patent No. 4,141,487 (Faust et al.) concerns a vapor-tight package comprising a plastic film which is formed with a slit along a crease line. The edges of the slit are sealed together by an adhesive sealant ~laterial ,,
-2-that melts below the cooking temperature to open the slit and thereby release vapors.
U.S. Patent No~ 4,404,241 (Mueller et al.) concerns a vapor-tight package comprising a heat-resistant S sheet formed with apertures, and bonded to that sheet is a continuous heat-softening material which extends across the apertures. Rising temperaturqs and pressures within the package cause the heat-softening material to flow to create vents through the apertures.
U.S. Patent No. 4,390,554 (Levinson) concerns a vapor~tight, multi-layer microwave oven package including a liquid-barrier plastic film 4 such as nylon or polyester which is "designed to vent at a preselected temperature by blow out plugs 13 or can be constructed of a low tempera-ture plastic (as polyethylene) formulated to melt at a predetermined temperature". See col. 4, lines 30-40, and Fig. 1.
U.S. Patent No. 4,210,674 (Mitchell) illustrates a tray which is hermetically sealed by a plastic film to which a narrow strip of aluminum foil is adhesively secured. When the aluminum foil has certain dimensions, it converts microwave energy to heat sufficient to melt the plastic film, thus venting the package. When we con-structed such a package, the venting clid occur, but there 2~ was visible and audible arcing which would probably be objectionable to prospective users. Also, it was difficult to adhere such a narrow strip of aluminum foil to a plastic film. Furthermore, many food processors routinely monitor their products to locate any hazardous metal ob~ects, and such an aluminum strip might interfere.
The Mitchell patent suggests at column 3, lines 18-30 that substitutes for the aluminum foil include "silver micropaint", "a copper-filled coating" and "dispersions of metal powder", and that ~uch substituents may be applied by "a printing wheel or a spray applicator".
~24~17(~
other Prior Art U.S. Patent No. 4,434,197 concerns a reusable flexible sheet containing semi-conductive or energy-absorbing material such as colloidal graphite, ferric oxide and carbon (col. 5, lines 26-32). When the sheet is wrapped around food to be cooked in a microwave oven the semi-conductive material becomes hot enough to permit browning or crisping of the food. The semi-conductive material is encapsulated between layers of polytetrafluoroethylene which is so heat resistant that the sheet can be reused.
Disclosure of Invention The invention concerns a vapor-tight package including means for automatically venting through the package upon heating in a microwave oven, as do the vapor-tight packages of the patents discussed above under "Background Art". The novel package differs from the above-discussed prior packages in that its venting means is a deposit which is adhered to the package and comprises nonmetallic, microwave-absorbing particles dispersed in a nonmetallic binder, preferably a polymeric binder, which deposit has a thickness within the range from 10 to 300 micrometers, said particles comprising at least 10% by weight of said deposit.
Preferred nonmetallic, microwave-absorbing particles are graphite and carbon black particles.
Somewhat less, but still highly absorptive of microwave energy, are iron oxide and ferrite particles. All such nonmetallic particles which are highly-absorptive of microwave energy are hereinafter called "microwave-absorbing particles".
When the package comprises heat-sensitive material such as thermoplastic film and the deposit is adhered to the film, heating of the particles by microwaves can soften and weaken that portion of the film to which the deposit is adhered, thus venting the package through that ~L2~1701 ~4--portion. When an unfilled adhesive layer adheres the deposit to a packaging material which is to be weakened by heat from the particles, that adhesive layer should be thin to afford good heat transfer, preferably from 10 to 20 micrometers.
When the deposit itself is impervious to vapors, but softens and weakens when heated by the particles, it can be positioned over a weakness in the package such as an opening, a slit, or a score. When qo used, it may be desirable to cover the deposit with a vapor-impervious thermoplastic film. Upon doing so, heat from the particles may either soften and weaken the covering thermoplastic film, or venting may occur lateral]y through the deposit or through an unfilled adhesive layer by which the deposit is adhered over a weakness of the package.
For economy, the nonmetallic binder of the deposit should be the minimum proportion that will firmly anchor the microwave-absorbing particles but, when the binder also serves to adhere the deposit to the package, that proportion should be high enough to assure good adhe~ion. The particles should be firmly anchored when the binder comprises at least 30% by weight of the deposit, but when the binder also serves as an adhesive, it preferably comprises more than 50 weight percent of the deposit. When a separate adhesive coating is used, the binder preferably comprises from 30 to 80 weight percent of the deposit.
Particles which are substantially le~s absorptive of microwave energy than is graphite preferably comprise about 60% by weight of the deposit.
The dispersion of microwave-absorbing particles in nonmetallic binder can be printed or otherwise directly deposited onto the packaging. When printed, the deposit can form an alpha-numeric message or a distinctive pattern that inform~ the user of the self-venting nature ~f the package. Whether printed or cut from a preformed sheet, the deposit may be shaped to concentrate the microwave energy. Preliminary experiments suggest that notches in , the edges of ~he deposit have such effect, but this has not been confirmedO Preferably the deposit has a distincti-~e shape to remind the user by its very appearance that the package is self-venting and to position the package in the S oven so that nothing spills when the vent forms~ For such reasons, the deposit preferably is highly conspicuous. The deposit may have the shape of a logo or trademark to identify the company marketing the package.
For convenience and economy, the deposit may be a psece of a layer of tape which itself is believed to be novel. Such a tape comprises a carrier web, adhered to the carrier web a layer of particles selected from a graphite and carbon black dispersed in nonmetallic binder, said particles comprising at least 10% by weight of the layer, the layer having a thickness within the range from 10 to 300 micrometers, and means for adhering a piece of said layer to a package to provide self-venting of the package in a microwave oven.
The particle-containing layer may be coextensive with the carrier web and may be die-cut in the form of individual shapes such as a star or a diamond, at least one piece to be adhered to each package to provide a venting deposit.
While the nonmetallic binder may serve to adhere the pieces to a package to be vented as is pointed out above, the tape may include an unfilled adhesive layer.
The carrier web of the tape may have a low-adhesion surface from which pieces of the particle-containing layer can be cleanly peeled, thus permitting the carrier web to be reused. On the other hand, the carrier web can remain firmly adhered to the deposit. When the carrier web is vapor-impervious and is selected to soften and weaken when the microwave-absorbing particles of the deposit are heated by microwave energy, the package can be made with a heat-resistant plastic film ~uch as cellophane which the 7~
deposit would not soften hy positioning the deposit over a weakness in the package such as an opening, slit, or score.
To insure reliable venting before a package explodes due to vapor pressure buildup, the deposit preferably has a thickness of at least 20 micrometers and a width of at least 5 mm in all directions. At lesser dimensions, heat might he conducted or radiated away from the microwave-absorbing particles before it could produce the desired venting. Thicknesses greater than 100 micrometers may be economically wasteful and may cause arcing in a microwave oven.
Because of lateral heat conduction, the venting usually occurs at the center of the deposit. A deposit in the shape of a "C" or "U" tends to produce venting along a correspondingly shaped line, and this may open a flap to create quite a large vent. A vent produced by a small circular deposit may be so small that vapor pressures are not sufficiently relieved to avoid an explosion. For this reason, a circular deposit preferably is at least 5 mm in diameter, more preferably at least 1.0 cm in diame~er.
Larger packages may have several vent-producing deposits to insure against explosion.
For convenience to the user, the deposit may be placed at a position to enhance the opening of the package to remove its contents. When the package comprises an oriented thermoplastic film, such positioning may take advantage of the tear characteristics of the film.
The novel vapor-tight package may comprise a thermoplastic film sealed across the rim of a tray or the mouth of a jar with the deposit adhered to the film. If the thermoplastic film envelops a tray, the deposit preferably is applied to the film at a position within the rim of the tray.
Self-venting packages of the invention can be put to uses other than in a microwave oven. A package which is intended for processing in boiling water may employ a deposit which does not vent at 100C.
~Z4~7CI'~L
The self-venting depo~it uqually, but not necessarily, is intended for application to the exterior of d package. When a package comprises two plies of thermoplastic film, the deposit may be positioned between the two plies.
Brief Description of the Drawing In the drawing:
Fig. 1 is a schematic edgeview of a first tape of the invention which is useful for making a self venting, vapor-tight package of the invention;
Fig. 2 is a schematic sectional view of a pouch-like package of the invention wherein a piece of the tape of Fig. 1 provides a self-venting deposit;
Fig. 3 is a schematic edgeview of a second tape of the invention;
Fig. 4 is a schematic sectional view of a second package of the invention wherein a piece of the tape of Fig. 3 provides a self-venting deposit Fig. 5 is a fragmental schemat;c top view of a third self-venting microwave oven package of the invention;
and Fig. 6 fragmentally shows in perspective a fourth self-venting microwave oven package of the invention.
Detailed Description The tape 10 shown in Fig. 1 has a low-adhesion silicone paper carrier web 12 to which is releasably adhered a pressure-sensitive adhesive layer 14~ Adhered in turn to the adhesive layer 14 is a layer 16 consisting of a dispersion of graphite particles in a polymeric binder.
The tape 10 with its carrier web 12 can be wound upon itself for convenience in storage and shipment.
Upon peeling off the carrier web 12, a rectangular piece of particle-containing layer 16 of the tape i8 adhered by its adhesive layer 14 to a vapor-tight, pouch-like package 17 (Fig. 2) comprising thermoplastic ~Z41~70~
film 18. When the package 17 is heated in a microwave oven, heat generated by microwave eneryy absorbed by the graphite particles of the layer 16 softens and weakens the underlying portion of the thermoplastic film 18, whereupon vapor pressure generated in the package vents the package 17 through that portion and the deposited piece of the tape.
The tape 20 shown in Fig. 3 consists of a low-density polyethylene carrier web 22 to which is adhered a layer 24 that is a dispersion of colloidal graphite particles in a pressure-sensitive adhesive. When the open face 25 of the carrier web 22 has a low-adhesion surface, the tape 20 can be wound upon itself for convenient storage and shipment.
The package 30 shown in Fig. 4 has a molded plastic tray 32 across which is sealed a thermoplastic film 34O Adhered to the outer surface o~ the thermoplastic film is a deposit of a piece of the tape 20 of Fig. 3 which covers a perforation 36 in the plastic film. Heat generated by microwave energy absorbed by the graphite particles of the layer 24 softens and weakens both the adhesive of the layer 24 and the polyethylene web 22 to vent the package.
The fragment of a package 40 shown in Fig. 5 2S includes a thermoplastic film 42 to which is adhered a deposit 44 consisting of microwave-absorbing particles dispersed in an organic binder. The distinctive U-shape of the deposit 44 ~ay be created either by printing a dispersion of the particles in a solution of the binder, or by die-cutting such a shape from the particle-containing tape 10 of Fig. 1 and adhering that shape by its adhesive layer 14 to the plastic film 42. Notches 45 in the edges of the deposit 44 may concentrate the absorbed microwave energy. When the particles are heated by microwave energy, that heat flows to and tends to soften and weaken the film 42 along the dotted line 46 which may result in a flap-like vent. When a package as shown in Fig. 5 was tested, the flap like vent served as a pull tab for tearing the package.
The fragment of a package 50 shown in Fig. 6 includes a plastic film 52 to which a piece 54 of a 5 microwave-absorbing particle-filled layer is adhered by an adhesive layer 56 which softens and melts at a temperature lower ~han does the binder of the piece 54. Before doing so, a slit 5~ was made in the film 52. Thus the package 50 is vented when the v~por pressure builds to a level sufficient to soften and open a channel laterally through the adhesive layer 56. The slit 5~ would not be visible through the piece 54 due to the opacity provided by its microwave-absorbing particles~
In the following examples, all parts are by weight except as noted.
Exa~le_l The following were placed in a glass jar and mixed overnight on a laboratory shaker:
45 grams - Practical graphite powder (GX-0279, Matheson - Coleman & Bell, Norwood, OH) 45 grams - Soluble polyester of (on a molar basis) terephthalic acid (23~), isophthalic acid (21%), aliphatic diacids (7%), ethylene glycol (27%), and neopentyl glycol (21%), available as "Vitel PE 222" from B. F.
Goodrich.
114.6 grams - Toluene 20.4 grams Methyl ethyl ketone The resulting dispersion was coated onto a 40-micrometer thick biaxially-oriented polypropylene film using a laboratory k~ife coater with a 250-micrometer orifice; then dried in an oven at 66C for 10 minutes. A layer of pressure-sen~itive aclhesive was laminated to the dried coating to provide a tape of the invention.
For testing purposes, a pouch of fro~en corn was purchased at a grocery store. The pouch was believed to be a laminate of polyethylene film and biaxially-oriented polyethylene terphthalate film, the latter at the exterior.
A 2.54 x 2.54 cm piece of the tape of the invention was adhered by its adhesive layer to the pouch while the corn was frozen, and the polypropylene film was peeled off and diAcarded. Following instructions on the corn package except not puncturing the pouch, the corn was cooked for 7 10 minutes in a microwave oven. At three minutes, the pouch vented automatically through the tape deposit, and steam continued to escape through the vent during the final four minutes.
Example 2 The following were placed in a glass jar and mixed overnight on a laboratory shaker:
8 grams - Carbon black ("Monarch 700" from Cabot Corp., Boston, MA).
8 grams - Soluble polyester of Example 1 54.4 grams - Toluene 9.6 grams - Methyl ethyl ketone The resulting dispersion was coated over a release coating 2S on a 40-micrometer thick biaxially-oriented polypropylene film using a laboratory knife coater with a 250-micrometer orifice; then dried in an oven at 66C for 10 minutes. A
layer of pressure-sensitive adhesive was laminated to the dried coating. The polypropylene film was ~hen removed, 30 and another layer of the same adhesive was laminated to the exposed face of the dried coating.
Used for testin~ purposes was a 10 by 15 cm pouch of a duplex film, the outer layer of which was biaxially-oriented poly(ethylene terephthalate) film and the inner 35 layer of which was polyethylene. After inserting a paper towel and 12 ml of water, the pouch was sealed. A 2.5~ by 2.54 cm piece of the double-coated tape was adhered by its ~241~7~1 second adhesive layer to the exterior of the pouch. When the pouch was placed in a microwave oven (high setting), within 12 seconds the pouch vented through the duplex film beneath the deposited piece of tape.
Example 3 The following were placed in a glass jar and mixed overnight on a laboratory shaker:
50 grams - 22% solution of a pressure-sensitive adhesive copolymer of isooctyl acrylate (95.5) and acrylic acid (4.5) in heptane and isopropyl alcohol.
11 grams - Practical graphite powder of Example 1 The resulting dispersion was coated onto silicone-coated release paper using a laboratory knife coater with a 300-micrometer orifice; then dried in an oven at 66C for 10 minutes. A 50-micrometer low-density polyethylene film was laminated to the exposed surface of the dried coating, with the preasure-senqitive adhesive copolymer of the coating serving as the laminating adhesive, thus providing a tape of the invention.
A 1.3 by 5.1 cm piece of the tape, after stripping off the release paper, was adhered by the adhesive matrix of the graphite layer to a p~uch containing a paper towel and water as described in Example 2. The pouch was then placed in a microwave oven (high setting).
Within one minute, heat generated in the graphite powder weakened the pouch immediately beneath the tape deposit, thus venting the pouch through the weakened spot.
Example 4 A tape was made having at its backing a plastic film (believed to be polytetrafluoroethylene) 250 micrometers thick, throughout which was dispersed graphite powder comprising 40% by weight of the backing ("DC 7035"
from Dixon Indu~tries, Bristolr RI). To one face of the 7~
backing was laminated a layer oE unfilled pressure-sensitive adhesive to provide a tape of the invention.
A 2.5 by 2.5 cm piece of the tape ~as adhered by its adhesive layer to a pouch containing a paper towel and water as described in Example 2. The pouch was placed in a microwave oven (high setting) for one minu~e. The tape weakened the bag at the spot it was applied, and the pressure built by the steam ruptured through the bag but not the tape. Instead, the steam channeled through the adhesive and the pressure was relieved.
Example 5 A 3.~3 by 1.3 cm piece of tape as described in Example 1 was placed over a 2.5 cm slit in a paper/aluminum-foil/polyethylene lid (137.5 micrometers thick) called "~et Cadet Lid Stock" that had been sealed to the top of a 37-ml high-density polyethylene unit dose cup which was half full of water. The cup was then placed in a microwave oven (high setting) and vented through the piece of tape soon after a slight bulging of the flexible lid was observed.
The term "vapor-tight package" is intended to encompass packages which contain a pressure-release valve of the type currently being used on some coffee packages.
~5
U.S. Patent No~ 4,404,241 (Mueller et al.) concerns a vapor-tight package comprising a heat-resistant S sheet formed with apertures, and bonded to that sheet is a continuous heat-softening material which extends across the apertures. Rising temperaturqs and pressures within the package cause the heat-softening material to flow to create vents through the apertures.
U.S. Patent No. 4,390,554 (Levinson) concerns a vapor~tight, multi-layer microwave oven package including a liquid-barrier plastic film 4 such as nylon or polyester which is "designed to vent at a preselected temperature by blow out plugs 13 or can be constructed of a low tempera-ture plastic (as polyethylene) formulated to melt at a predetermined temperature". See col. 4, lines 30-40, and Fig. 1.
U.S. Patent No. 4,210,674 (Mitchell) illustrates a tray which is hermetically sealed by a plastic film to which a narrow strip of aluminum foil is adhesively secured. When the aluminum foil has certain dimensions, it converts microwave energy to heat sufficient to melt the plastic film, thus venting the package. When we con-structed such a package, the venting clid occur, but there 2~ was visible and audible arcing which would probably be objectionable to prospective users. Also, it was difficult to adhere such a narrow strip of aluminum foil to a plastic film. Furthermore, many food processors routinely monitor their products to locate any hazardous metal ob~ects, and such an aluminum strip might interfere.
The Mitchell patent suggests at column 3, lines 18-30 that substitutes for the aluminum foil include "silver micropaint", "a copper-filled coating" and "dispersions of metal powder", and that ~uch substituents may be applied by "a printing wheel or a spray applicator".
~24~17(~
other Prior Art U.S. Patent No. 4,434,197 concerns a reusable flexible sheet containing semi-conductive or energy-absorbing material such as colloidal graphite, ferric oxide and carbon (col. 5, lines 26-32). When the sheet is wrapped around food to be cooked in a microwave oven the semi-conductive material becomes hot enough to permit browning or crisping of the food. The semi-conductive material is encapsulated between layers of polytetrafluoroethylene which is so heat resistant that the sheet can be reused.
Disclosure of Invention The invention concerns a vapor-tight package including means for automatically venting through the package upon heating in a microwave oven, as do the vapor-tight packages of the patents discussed above under "Background Art". The novel package differs from the above-discussed prior packages in that its venting means is a deposit which is adhered to the package and comprises nonmetallic, microwave-absorbing particles dispersed in a nonmetallic binder, preferably a polymeric binder, which deposit has a thickness within the range from 10 to 300 micrometers, said particles comprising at least 10% by weight of said deposit.
Preferred nonmetallic, microwave-absorbing particles are graphite and carbon black particles.
Somewhat less, but still highly absorptive of microwave energy, are iron oxide and ferrite particles. All such nonmetallic particles which are highly-absorptive of microwave energy are hereinafter called "microwave-absorbing particles".
When the package comprises heat-sensitive material such as thermoplastic film and the deposit is adhered to the film, heating of the particles by microwaves can soften and weaken that portion of the film to which the deposit is adhered, thus venting the package through that ~L2~1701 ~4--portion. When an unfilled adhesive layer adheres the deposit to a packaging material which is to be weakened by heat from the particles, that adhesive layer should be thin to afford good heat transfer, preferably from 10 to 20 micrometers.
When the deposit itself is impervious to vapors, but softens and weakens when heated by the particles, it can be positioned over a weakness in the package such as an opening, a slit, or a score. When qo used, it may be desirable to cover the deposit with a vapor-impervious thermoplastic film. Upon doing so, heat from the particles may either soften and weaken the covering thermoplastic film, or venting may occur lateral]y through the deposit or through an unfilled adhesive layer by which the deposit is adhered over a weakness of the package.
For economy, the nonmetallic binder of the deposit should be the minimum proportion that will firmly anchor the microwave-absorbing particles but, when the binder also serves to adhere the deposit to the package, that proportion should be high enough to assure good adhe~ion. The particles should be firmly anchored when the binder comprises at least 30% by weight of the deposit, but when the binder also serves as an adhesive, it preferably comprises more than 50 weight percent of the deposit. When a separate adhesive coating is used, the binder preferably comprises from 30 to 80 weight percent of the deposit.
Particles which are substantially le~s absorptive of microwave energy than is graphite preferably comprise about 60% by weight of the deposit.
The dispersion of microwave-absorbing particles in nonmetallic binder can be printed or otherwise directly deposited onto the packaging. When printed, the deposit can form an alpha-numeric message or a distinctive pattern that inform~ the user of the self-venting nature ~f the package. Whether printed or cut from a preformed sheet, the deposit may be shaped to concentrate the microwave energy. Preliminary experiments suggest that notches in , the edges of ~he deposit have such effect, but this has not been confirmedO Preferably the deposit has a distincti-~e shape to remind the user by its very appearance that the package is self-venting and to position the package in the S oven so that nothing spills when the vent forms~ For such reasons, the deposit preferably is highly conspicuous. The deposit may have the shape of a logo or trademark to identify the company marketing the package.
For convenience and economy, the deposit may be a psece of a layer of tape which itself is believed to be novel. Such a tape comprises a carrier web, adhered to the carrier web a layer of particles selected from a graphite and carbon black dispersed in nonmetallic binder, said particles comprising at least 10% by weight of the layer, the layer having a thickness within the range from 10 to 300 micrometers, and means for adhering a piece of said layer to a package to provide self-venting of the package in a microwave oven.
The particle-containing layer may be coextensive with the carrier web and may be die-cut in the form of individual shapes such as a star or a diamond, at least one piece to be adhered to each package to provide a venting deposit.
While the nonmetallic binder may serve to adhere the pieces to a package to be vented as is pointed out above, the tape may include an unfilled adhesive layer.
The carrier web of the tape may have a low-adhesion surface from which pieces of the particle-containing layer can be cleanly peeled, thus permitting the carrier web to be reused. On the other hand, the carrier web can remain firmly adhered to the deposit. When the carrier web is vapor-impervious and is selected to soften and weaken when the microwave-absorbing particles of the deposit are heated by microwave energy, the package can be made with a heat-resistant plastic film ~uch as cellophane which the 7~
deposit would not soften hy positioning the deposit over a weakness in the package such as an opening, slit, or score.
To insure reliable venting before a package explodes due to vapor pressure buildup, the deposit preferably has a thickness of at least 20 micrometers and a width of at least 5 mm in all directions. At lesser dimensions, heat might he conducted or radiated away from the microwave-absorbing particles before it could produce the desired venting. Thicknesses greater than 100 micrometers may be economically wasteful and may cause arcing in a microwave oven.
Because of lateral heat conduction, the venting usually occurs at the center of the deposit. A deposit in the shape of a "C" or "U" tends to produce venting along a correspondingly shaped line, and this may open a flap to create quite a large vent. A vent produced by a small circular deposit may be so small that vapor pressures are not sufficiently relieved to avoid an explosion. For this reason, a circular deposit preferably is at least 5 mm in diameter, more preferably at least 1.0 cm in diame~er.
Larger packages may have several vent-producing deposits to insure against explosion.
For convenience to the user, the deposit may be placed at a position to enhance the opening of the package to remove its contents. When the package comprises an oriented thermoplastic film, such positioning may take advantage of the tear characteristics of the film.
The novel vapor-tight package may comprise a thermoplastic film sealed across the rim of a tray or the mouth of a jar with the deposit adhered to the film. If the thermoplastic film envelops a tray, the deposit preferably is applied to the film at a position within the rim of the tray.
Self-venting packages of the invention can be put to uses other than in a microwave oven. A package which is intended for processing in boiling water may employ a deposit which does not vent at 100C.
~Z4~7CI'~L
The self-venting depo~it uqually, but not necessarily, is intended for application to the exterior of d package. When a package comprises two plies of thermoplastic film, the deposit may be positioned between the two plies.
Brief Description of the Drawing In the drawing:
Fig. 1 is a schematic edgeview of a first tape of the invention which is useful for making a self venting, vapor-tight package of the invention;
Fig. 2 is a schematic sectional view of a pouch-like package of the invention wherein a piece of the tape of Fig. 1 provides a self-venting deposit;
Fig. 3 is a schematic edgeview of a second tape of the invention;
Fig. 4 is a schematic sectional view of a second package of the invention wherein a piece of the tape of Fig. 3 provides a self-venting deposit Fig. 5 is a fragmental schemat;c top view of a third self-venting microwave oven package of the invention;
and Fig. 6 fragmentally shows in perspective a fourth self-venting microwave oven package of the invention.
Detailed Description The tape 10 shown in Fig. 1 has a low-adhesion silicone paper carrier web 12 to which is releasably adhered a pressure-sensitive adhesive layer 14~ Adhered in turn to the adhesive layer 14 is a layer 16 consisting of a dispersion of graphite particles in a polymeric binder.
The tape 10 with its carrier web 12 can be wound upon itself for convenience in storage and shipment.
Upon peeling off the carrier web 12, a rectangular piece of particle-containing layer 16 of the tape i8 adhered by its adhesive layer 14 to a vapor-tight, pouch-like package 17 (Fig. 2) comprising thermoplastic ~Z41~70~
film 18. When the package 17 is heated in a microwave oven, heat generated by microwave eneryy absorbed by the graphite particles of the layer 16 softens and weakens the underlying portion of the thermoplastic film 18, whereupon vapor pressure generated in the package vents the package 17 through that portion and the deposited piece of the tape.
The tape 20 shown in Fig. 3 consists of a low-density polyethylene carrier web 22 to which is adhered a layer 24 that is a dispersion of colloidal graphite particles in a pressure-sensitive adhesive. When the open face 25 of the carrier web 22 has a low-adhesion surface, the tape 20 can be wound upon itself for convenient storage and shipment.
The package 30 shown in Fig. 4 has a molded plastic tray 32 across which is sealed a thermoplastic film 34O Adhered to the outer surface o~ the thermoplastic film is a deposit of a piece of the tape 20 of Fig. 3 which covers a perforation 36 in the plastic film. Heat generated by microwave energy absorbed by the graphite particles of the layer 24 softens and weakens both the adhesive of the layer 24 and the polyethylene web 22 to vent the package.
The fragment of a package 40 shown in Fig. 5 2S includes a thermoplastic film 42 to which is adhered a deposit 44 consisting of microwave-absorbing particles dispersed in an organic binder. The distinctive U-shape of the deposit 44 ~ay be created either by printing a dispersion of the particles in a solution of the binder, or by die-cutting such a shape from the particle-containing tape 10 of Fig. 1 and adhering that shape by its adhesive layer 14 to the plastic film 42. Notches 45 in the edges of the deposit 44 may concentrate the absorbed microwave energy. When the particles are heated by microwave energy, that heat flows to and tends to soften and weaken the film 42 along the dotted line 46 which may result in a flap-like vent. When a package as shown in Fig. 5 was tested, the flap like vent served as a pull tab for tearing the package.
The fragment of a package 50 shown in Fig. 6 includes a plastic film 52 to which a piece 54 of a 5 microwave-absorbing particle-filled layer is adhered by an adhesive layer 56 which softens and melts at a temperature lower ~han does the binder of the piece 54. Before doing so, a slit 5~ was made in the film 52. Thus the package 50 is vented when the v~por pressure builds to a level sufficient to soften and open a channel laterally through the adhesive layer 56. The slit 5~ would not be visible through the piece 54 due to the opacity provided by its microwave-absorbing particles~
In the following examples, all parts are by weight except as noted.
Exa~le_l The following were placed in a glass jar and mixed overnight on a laboratory shaker:
45 grams - Practical graphite powder (GX-0279, Matheson - Coleman & Bell, Norwood, OH) 45 grams - Soluble polyester of (on a molar basis) terephthalic acid (23~), isophthalic acid (21%), aliphatic diacids (7%), ethylene glycol (27%), and neopentyl glycol (21%), available as "Vitel PE 222" from B. F.
Goodrich.
114.6 grams - Toluene 20.4 grams Methyl ethyl ketone The resulting dispersion was coated onto a 40-micrometer thick biaxially-oriented polypropylene film using a laboratory k~ife coater with a 250-micrometer orifice; then dried in an oven at 66C for 10 minutes. A layer of pressure-sen~itive aclhesive was laminated to the dried coating to provide a tape of the invention.
For testing purposes, a pouch of fro~en corn was purchased at a grocery store. The pouch was believed to be a laminate of polyethylene film and biaxially-oriented polyethylene terphthalate film, the latter at the exterior.
A 2.54 x 2.54 cm piece of the tape of the invention was adhered by its adhesive layer to the pouch while the corn was frozen, and the polypropylene film was peeled off and diAcarded. Following instructions on the corn package except not puncturing the pouch, the corn was cooked for 7 10 minutes in a microwave oven. At three minutes, the pouch vented automatically through the tape deposit, and steam continued to escape through the vent during the final four minutes.
Example 2 The following were placed in a glass jar and mixed overnight on a laboratory shaker:
8 grams - Carbon black ("Monarch 700" from Cabot Corp., Boston, MA).
8 grams - Soluble polyester of Example 1 54.4 grams - Toluene 9.6 grams - Methyl ethyl ketone The resulting dispersion was coated over a release coating 2S on a 40-micrometer thick biaxially-oriented polypropylene film using a laboratory knife coater with a 250-micrometer orifice; then dried in an oven at 66C for 10 minutes. A
layer of pressure-sensitive adhesive was laminated to the dried coating. The polypropylene film was ~hen removed, 30 and another layer of the same adhesive was laminated to the exposed face of the dried coating.
Used for testin~ purposes was a 10 by 15 cm pouch of a duplex film, the outer layer of which was biaxially-oriented poly(ethylene terephthalate) film and the inner 35 layer of which was polyethylene. After inserting a paper towel and 12 ml of water, the pouch was sealed. A 2.5~ by 2.54 cm piece of the double-coated tape was adhered by its ~241~7~1 second adhesive layer to the exterior of the pouch. When the pouch was placed in a microwave oven (high setting), within 12 seconds the pouch vented through the duplex film beneath the deposited piece of tape.
Example 3 The following were placed in a glass jar and mixed overnight on a laboratory shaker:
50 grams - 22% solution of a pressure-sensitive adhesive copolymer of isooctyl acrylate (95.5) and acrylic acid (4.5) in heptane and isopropyl alcohol.
11 grams - Practical graphite powder of Example 1 The resulting dispersion was coated onto silicone-coated release paper using a laboratory knife coater with a 300-micrometer orifice; then dried in an oven at 66C for 10 minutes. A 50-micrometer low-density polyethylene film was laminated to the exposed surface of the dried coating, with the preasure-senqitive adhesive copolymer of the coating serving as the laminating adhesive, thus providing a tape of the invention.
A 1.3 by 5.1 cm piece of the tape, after stripping off the release paper, was adhered by the adhesive matrix of the graphite layer to a p~uch containing a paper towel and water as described in Example 2. The pouch was then placed in a microwave oven (high setting).
Within one minute, heat generated in the graphite powder weakened the pouch immediately beneath the tape deposit, thus venting the pouch through the weakened spot.
Example 4 A tape was made having at its backing a plastic film (believed to be polytetrafluoroethylene) 250 micrometers thick, throughout which was dispersed graphite powder comprising 40% by weight of the backing ("DC 7035"
from Dixon Indu~tries, Bristolr RI). To one face of the 7~
backing was laminated a layer oE unfilled pressure-sensitive adhesive to provide a tape of the invention.
A 2.5 by 2.5 cm piece of the tape ~as adhered by its adhesive layer to a pouch containing a paper towel and water as described in Example 2. The pouch was placed in a microwave oven (high setting) for one minu~e. The tape weakened the bag at the spot it was applied, and the pressure built by the steam ruptured through the bag but not the tape. Instead, the steam channeled through the adhesive and the pressure was relieved.
Example 5 A 3.~3 by 1.3 cm piece of tape as described in Example 1 was placed over a 2.5 cm slit in a paper/aluminum-foil/polyethylene lid (137.5 micrometers thick) called "~et Cadet Lid Stock" that had been sealed to the top of a 37-ml high-density polyethylene unit dose cup which was half full of water. The cup was then placed in a microwave oven (high setting) and vented through the piece of tape soon after a slight bulging of the flexible lid was observed.
The term "vapor-tight package" is intended to encompass packages which contain a pressure-release valve of the type currently being used on some coffee packages.
~5
Claims (15)
1. A vapor-tight package including means for automatically venting through the package upon heating in a microwave oven, wherein the venting means is a deposit which is adhered to the package and comprises nonmetallic, microwave-absorbing particles dispersed in a nonmetallic binder which deposit has a thickness within the range from 10 to 300 micrometers, said particles comprising at least 10% by weight of said deposit.
2. A package as defined in claim 1 wherein the microwave-absorbing particles are graphite.
3. A package as defined in claim 1 wherein the package comprises a plastic film, said deposit covering a weakness in the plastic film.
4. A package as defined in claim 1 wherein the binder is an adhesive which adheres the deposit to the package.
5. A package as defined in claim 1 wherein the deposit is printed.
6. A package as defined in claim 1 wherein said deposit has a thickness from 50 to 75 micrometers and a minimum breadth of 5 mm.
7. A tape for use in making the package of claim 1 wherein the tape comprises a carrier web, adhered to the carrier web a layer of particles selected from graphite and carbon black dispersed in nonmetallic binder, said particles comprising at least 10% by weight of the layer, the layer having a thickness with the range from 10 to 300 micrometers, and means for adhering a piece of said layer to a package to provide self venting of the package in a microwave oven.
8, A tape as defined in claim 7 wherein the carrier web has a low-adhesion surface from which said particle-containing layer is readily separated.
9. A tape as defined in claim 7 wherein the microwave-absorbing particles are graphite.
10. A tape as defined in claim 7 wherein the binder is an adhesive which functions as said means for adhering.
11. A tape as defined in claim 7 wherein the adhering means is a layer of unfilled adhesive covering the layer of particles.
12. A tape as defined in claim 7 wherein said carrier web is a thermoplastic film to which the particle-containing layer is permanently adhered, which thermoplastic film is softened and weakened by heat generated in the particles when they absorb microwave energy.
13. A method for venting in a microwave oven a vapor-tight package, said method comprising the sequential steps of:
(1) dispersing nonmetallic microwave-absorbing particles in a binder to provide a dispersion, of which said particles comprise at least 10% by weight and (2) depositing a piece of the dispersion onto said package, which piece has a thickness within the range from 10 to 300 micrometers.
(1) dispersing nonmetallic microwave-absorbing particles in a binder to provide a dispersion, of which said particles comprise at least 10% by weight and (2) depositing a piece of the dispersion onto said package, which piece has a thickness within the range from 10 to 300 micrometers.
14. A method as defined in claim 13 wherein the binder is an adhesive which adheres strongly to the plastic film.
15. A method as defined in claim 13 wherein prior to step (2) the dispersion is formed into a strip, there is an additional step of applying an adhesive layer to the strip, and a piece of the adhesive-bearing strip is adhered by said adhesive layer to the package in step (2).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/647,882 US4640838A (en) | 1984-09-06 | 1984-09-06 | Self-venting vapor-tight microwave oven package |
US647,882 | 1984-09-06 |
Publications (1)
Publication Number | Publication Date |
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CA1241701A true CA1241701A (en) | 1988-09-06 |
Family
ID=24598643
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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CA000488438A Expired CA1241701A (en) | 1984-09-06 | 1985-08-09 | Self-venting vapor-tight microwave oven package |
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US (1) | US4640838A (en) |
EP (1) | EP0174188B1 (en) |
JP (1) | JPS6169576A (en) |
KR (1) | KR930002049B1 (en) |
AR (1) | AR245919A1 (en) |
AU (2) | AU585244B2 (en) |
BR (1) | BR8504131A (en) |
CA (1) | CA1241701A (en) |
DE (1) | DE3571593D1 (en) |
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MX (1) | MX163238B (en) |
NO (1) | NO160702C (en) |
PH (1) | PH22232A (en) |
ZA (1) | ZA856823B (en) |
Families Citing this family (160)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5306512A (en) * | 1985-05-09 | 1994-04-26 | Bagcraft Corporation Of America | Method and means for enhancing microwave popping of popcorn |
US4873101A (en) * | 1985-09-26 | 1989-10-10 | Minnesota Mining And Manufacturing Company | Microwave food package and grease absorbent pad therefor |
CA1283384C (en) * | 1985-09-26 | 1991-04-23 | Curtis L. Larson | Microwave food package |
US4961944A (en) * | 1985-10-19 | 1990-10-09 | Gourmec Laboratory Co., Ltd. | Package for microwave oven cooking and method of use |
US5308945A (en) * | 1986-03-17 | 1994-05-03 | James River Corporation | Microwave interactive printable coatings |
JPH0825583B2 (en) * | 1986-03-27 | 1996-03-13 | ハウス食品株式会社 | Sealed container for cooking |
JPS62265799A (en) * | 1986-05-14 | 1987-11-18 | 横浜ゴム株式会社 | Manufacture of multilayer wave absorber |
JPS62248299A (en) * | 1986-04-22 | 1987-10-29 | 横浜ゴム株式会社 | Electric wave absorbing composite unit |
JPS62271864A (en) * | 1986-05-09 | 1987-11-26 | 東洋製罐株式会社 | Sealed vessel |
US5190777A (en) * | 1986-07-18 | 1993-03-02 | American Home Food Products, Inc. | Package for microwaving popcorn |
US4786513A (en) * | 1986-12-05 | 1988-11-22 | Conagra, Inc. | Package for sliced bacon adapted for microwave cooking |
US4786773A (en) * | 1986-12-18 | 1988-11-22 | Alcan International Limited | Systems and methods for determining doneness of microwave-heated bodies |
EP0274553B1 (en) * | 1987-01-13 | 1990-06-13 | Thomas Philipp | Method of manufacturing and packing a fresh product of vegetables and fruits and the like |
JPH0615880Y2 (en) * | 1987-04-01 | 1994-04-27 | 大日本印刷株式会社 | Food packaging for microwave cooking |
US5041295A (en) * | 1987-07-06 | 1991-08-20 | The Pillsbury Company | Package for crisping the surface of food products in a microwave oven |
US4940158A (en) * | 1987-09-22 | 1990-07-10 | American National Can Company | Container and seam ring for container |
EP0440792B1 (en) * | 1987-10-05 | 1993-09-15 | Toyo Seikan Kaisha, Ltd. | Sealed container for cooking in microwave range |
JPH0811591B2 (en) * | 1988-04-25 | 1996-02-07 | 東洋製罐株式会社 | Microwave oven sealed container |
US4810844A (en) * | 1987-11-30 | 1989-03-07 | Anderson Alan R | Microwave popcorn package |
US5500235A (en) * | 1987-12-07 | 1996-03-19 | Packaging Concepts, Inc. | Method for making a microwavable, expandable package |
US4911960A (en) * | 1988-01-19 | 1990-03-27 | National Starch And Chemical Corporation | Laminating adhesive for film/paper microwavable products |
JPH01134081U (en) * | 1988-03-07 | 1989-09-12 | ||
US4864089A (en) * | 1988-05-16 | 1989-09-05 | Dennison Manufacturing Company | Localized microwave radiation heating |
US4959516A (en) * | 1988-05-16 | 1990-09-25 | Dennison Manufacturing Company | Susceptor coating for localized microwave radiation heating |
US4876423A (en) * | 1988-05-16 | 1989-10-24 | Dennison Manufacturing Company | Localized microwave radiation heating |
US4859822A (en) * | 1988-05-19 | 1989-08-22 | Mobil Oil Corporation | Microwaveable container |
US4904836A (en) * | 1988-05-23 | 1990-02-27 | The Pillsbury Co. | Microwave heater and method of manufacture |
US4925684A (en) * | 1988-08-19 | 1990-05-15 | Campbell Soup Company | Food package with a microwave releasable sealed closure |
US4911938A (en) * | 1988-08-22 | 1990-03-27 | E. I. Du Pont De Nemours And Company | Conformable wrap susceptor with releasable seal for microwave cooking |
US5175031A (en) * | 1988-10-24 | 1992-12-29 | Golden Valley Microwave Foods, Inc. | Laminated sheets for microwave heating |
US4959231A (en) * | 1988-11-30 | 1990-09-25 | Marquee Foods, Incorporated | Microwave food packaging |
US5070223A (en) * | 1989-03-01 | 1991-12-03 | Colasante David A | Microwave reheatable clothing and toys |
US5254354A (en) * | 1990-12-07 | 1993-10-19 | Landec Corporation | Food package comprised of polymer with thermally responsive permeability |
US4950859A (en) * | 1989-03-27 | 1990-08-21 | Anderson Alan R | Bag for containing edibles during microwave cooking |
US4937410A (en) * | 1989-03-27 | 1990-06-26 | Anderson Alan R | Bag for containing edibles during microwave cooking |
CA2011740A1 (en) * | 1989-04-07 | 1990-10-07 | Glen Connell | Microwave heatable materials |
US5171950A (en) * | 1989-09-11 | 1992-12-15 | General Mills, Inc. | Flexible pouch and paper bag combination for use in the microwave popping of popcorn |
CA2025130A1 (en) * | 1989-10-02 | 1991-04-03 | Joseph F. Garvey | Microwave food package |
US5241150A (en) * | 1989-10-02 | 1993-08-31 | Minnesota Mining And Manufacturing Company | Microwave food package |
US5053594A (en) * | 1989-11-09 | 1991-10-01 | Rich-Seapak Processing Corporation | Cook and serve food package for the storing and heating by microwave energy of a food item |
US5012068A (en) * | 1989-11-15 | 1991-04-30 | Anderson Alan R | Susceptor for converting microwave energy into heat and method of use |
US4970358A (en) * | 1989-12-22 | 1990-11-13 | Golden Valley Microwave Foods Inc. | Microwave susceptor with attenuator for heat control |
US5254073A (en) | 1990-04-27 | 1993-10-19 | Kapak Corporation | Method of making a vented pouch |
US5059036A (en) * | 1990-04-27 | 1991-10-22 | Kapak Corporation | Vented pouch arrangement and method |
US5012061A (en) * | 1990-07-09 | 1991-04-30 | Lesser Emmett H | Microwave safety lid |
BR9102998A (en) * | 1990-08-02 | 1992-04-28 | Du Pont | MICROWAVE COOKING FOOD PACKAGING WITH EASY TO OPEN SEWING |
US5665822A (en) * | 1991-10-07 | 1997-09-09 | Landec Corporation | Thermoplastic Elastomers |
EP0496130B1 (en) * | 1990-12-21 | 1995-09-13 | The Procter & Gamble Company | Microwave susceptor incorporating a coating material having a silicate binder and an active constituent |
US5298708A (en) * | 1991-02-07 | 1994-03-29 | Minnesota Mining And Manufacturing Company | Microwave-active tape having a cured polyolefin pressure-sensitive adhesive layer |
US5307985A (en) * | 1991-12-17 | 1994-05-03 | Societe De Constructions De Materiel Metallique Et Electrique | Container and process for its manufacture |
US5414248A (en) * | 1991-12-24 | 1995-05-09 | Eastman Chemical Company | Grease and moisture absorbing inserts for microwave cooking |
FR2698082B1 (en) * | 1992-11-13 | 1994-12-23 | Mat Metallique Elec Const | Gas tight container. |
US5407087A (en) * | 1992-12-30 | 1995-04-18 | Lever Brothers Company, Division Of Conopco, Inc. | Venting closure |
US5454471A (en) * | 1993-03-24 | 1995-10-03 | W. L. Gore & Associates, Inc. | Insulative food container employing breathable polymer laminate |
US5419096A (en) * | 1993-07-28 | 1995-05-30 | World Class Packaging Systems, Inc. | Packaging method and apparatus for packaging large meat products in a desired gaseous atmosphere |
US5322182A (en) * | 1993-05-21 | 1994-06-21 | Mobil Oil Corporation | Microwave container |
CA2116929C (en) * | 1993-05-21 | 1999-11-02 | Jill Ann Fritz | Microwaveable container |
FR2706472B1 (en) * | 1993-06-10 | 1995-09-01 | Breger Guy | Method for manufacturing a product from a hot-melt or thermosetting polymer comprising zones sensitive to electromagnetic radiation in the microwave field and product obtained. |
US5464969A (en) * | 1994-11-10 | 1995-11-07 | Curwood, Inc. | Self-venting microwaveable package and method of manufacture |
GB9526285D0 (en) * | 1995-12-21 | 1996-02-21 | Shimell Richard J | Polymeric films |
US5698306A (en) | 1995-12-29 | 1997-12-16 | The Procter & Gamble Company | Microwave susceptor comprising a dielectric silicate foam substrate coated with a microwave active coating |
US5880435A (en) * | 1996-10-24 | 1999-03-09 | Vesture Corporation | Food delivery container |
US6054698A (en) * | 1996-11-01 | 2000-04-25 | Mast; Roy Lee | Microwave retaining package for microwave cooking |
US5780824A (en) * | 1997-02-07 | 1998-07-14 | Lulirama International, Inc. | Expandable and self-venting novelty container for cooking microwavable popcorn |
US5971613A (en) | 1997-04-11 | 1999-10-26 | Kapak Corp. | Bag constructions having inwardly directed side seal portions |
US5958482A (en) * | 1997-10-20 | 1999-09-28 | General Mills, Inc. | Easily expandable nontrapping flexible paper microwavable popcorn package |
BR9807693A (en) * | 1997-12-18 | 2000-03-21 | Karl Keller | Packaging for foodstuffs and cooking process for foodstuffs |
US6095324A (en) * | 1998-02-04 | 2000-08-01 | Mullin; Robert | Food transportation container |
DK1122189T3 (en) * | 1998-05-27 | 2004-11-22 | Morinaga Milk Industry Co Ltd | Packaging material and container for sealing beverages and foodstuffs |
SE511353C2 (en) | 1998-06-23 | 1999-09-20 | Joel Haamer | Method and apparatus for boiling and vacuum packing of microwaves with microwaves |
US6844534B2 (en) | 1998-06-23 | 2005-01-18 | Micvac Ab | Process for microwave cooking and vacuum packing of food |
US5989608A (en) * | 1998-07-15 | 1999-11-23 | Mizuno; Maki | Food container for cooking with microwave oven |
US6053474A (en) * | 1998-09-16 | 2000-04-25 | Corning Consumer Products Company | Vent valve |
DE19912365A1 (en) | 1999-03-19 | 2000-09-21 | Roche Diagnostics Gmbh | Multi-layer analytical tool |
USD443205S1 (en) | 1999-05-14 | 2001-06-05 | Tenneco Packaging Inc. | Bottom for a container |
US6257401B1 (en) | 1999-05-14 | 2001-07-10 | Pactiv Corporation | Vented container with handles and embossment |
USD432914S (en) * | 1999-05-27 | 2000-10-31 | Pactiv Corporation | Bottom for a container |
USD433334S (en) * | 1999-05-27 | 2000-11-07 | Pactiv Corporation | Cover for a container |
US6306448B1 (en) | 1999-07-15 | 2001-10-23 | General Mills, Inc. | Easily expandable, nontrapping, flexible paper, microwave package |
US6733807B2 (en) | 1999-07-15 | 2004-05-11 | General Mills, Inc. | Easily expandable, nontrapping, flexible paper, microwave package |
US6660983B2 (en) | 2001-08-31 | 2003-12-09 | General Mills, Inc. | Easily expandable, nontrapping, flexible paper, microwave package |
DE29918753U1 (en) | 1999-08-09 | 2000-02-17 | Keller Karl | Food packaging |
USD439160S1 (en) | 1999-09-03 | 2001-03-20 | Tenneco Packaging Inc. | Container |
USD444382S1 (en) | 1999-10-06 | 2001-07-03 | Pactiv Corporation | Cover for a container |
PL354993A1 (en) | 1999-11-19 | 2004-03-22 | Conagra Foods, Inc. | Microwave packaging having patterned adhesive, and methods |
JP3707977B2 (en) * | 2000-02-01 | 2005-10-19 | 株式会社ザック | Packaged food and packaged food containers |
KR100469764B1 (en) | 2000-04-26 | 2005-02-02 | 가부시키가이샤 프라스토 | Packaging material and packaging product |
KR200199033Y1 (en) * | 2000-05-20 | 2000-10-02 | 이은정 | Coffee bag |
US6566637B1 (en) * | 2000-06-28 | 2003-05-20 | Cem Corporation | Microwave assisted content analyzer |
DE10037883A1 (en) * | 2000-08-03 | 2002-02-14 | Henkel Kgaa | Ferromagnetic resonance excitation and its use for heating particle-filled substrates |
US6534174B1 (en) | 2000-08-21 | 2003-03-18 | The Procter & Gamble Company | Surface bonded entangled fibrous web and method of making and using |
US6673158B1 (en) | 2000-08-21 | 2004-01-06 | The Procter & Gamble Company | Entangled fibrous web of eccentric bicomponent fibers and method of using |
JP3602043B2 (en) | 2000-09-19 | 2004-12-15 | 株式会社ザック | Packaging containers, packaged foods, and packaged feed |
US6887916B2 (en) * | 2000-12-28 | 2005-05-03 | Kimberly-Clark Worldwide, Inc. | Materials having controlled shrinkage and patterns and methods of making same |
US20080138474A1 (en) * | 2001-08-27 | 2008-06-12 | Pouch Pac Innovations, Llc | Heatable package with multi-purpose valve and method of manufacture |
US20060127549A1 (en) * | 2001-08-27 | 2006-06-15 | Murray R C | Heatable package with frangible seal and method of manufacture |
US20030049354A1 (en) * | 2001-08-27 | 2003-03-13 | R. Charles Murray | Packaging for use in heating food in a microwave oven and method of use |
SE520355C2 (en) * | 2002-03-18 | 2003-07-01 | Micvac Ab | One-way disposable valve for food packaging which, when sufficiently heated, emits an audible signal |
AU2003250390A1 (en) * | 2002-07-05 | 2004-01-23 | Burall Limited | Microwavable food package having a venting valve |
GB2393091A (en) * | 2002-09-11 | 2004-03-17 | Northern Foods Ltd | Food container with heat sensitive seal released by microwave susceptor |
EP1422163A1 (en) * | 2002-11-22 | 2004-05-26 | Amcor Flexibles Europe A/S | Food package for heating in an oven |
GB0229413D0 (en) * | 2002-12-17 | 2003-01-22 | Little Jem Product Company Ltd | Food additives,foods and methods |
US7141771B2 (en) * | 2003-01-15 | 2006-11-28 | Steamway Franchise Sales, Inc. | Microwave cooking tray with multiple floor patterns |
US7004632B2 (en) | 2003-03-31 | 2006-02-28 | The Glad Products Company | Ventable storage bag |
GB2401172A (en) * | 2003-04-08 | 2004-11-03 | Ffp Packaging Solutions Ltd | Heating food products within a sealed food package |
SE527398C2 (en) * | 2003-05-30 | 2006-02-28 | Micvac Ab | One-way valve for food packaging |
US7244223B2 (en) * | 2003-05-30 | 2007-07-17 | Avery Dennison Corporation | Food bag release valve |
GB0316708D0 (en) * | 2003-07-16 | 2003-08-20 | Dupont Teijin Films Us Ltd | Polymeric film |
US6960748B2 (en) * | 2003-10-09 | 2005-11-01 | Smurfit-Stone Container Enterprises, Inc. | Collapsible microwave popcorn box |
KR20060103897A (en) * | 2003-10-16 | 2006-10-04 | 파우치 팩 이노베이션즈, 엘엘씨. | Packaging release valve for microwavable food items |
JP4569249B2 (en) * | 2003-11-28 | 2010-10-27 | 東洋製罐株式会社 | Packaging container for microwave oven |
US20070212452A1 (en) * | 2003-12-12 | 2007-09-13 | Franklin Brian J | Food Additives, Foods and Methods of Making Foods |
US20060043093A1 (en) * | 2004-09-01 | 2006-03-02 | Cox Shirley J | Cooking apparatus and method of use |
US7985192B2 (en) | 2004-09-09 | 2011-07-26 | Fastform Research Limited | Geometrically apertured protective and/or splint device comprising a re-mouldable thermoplastic material |
US20050118315A1 (en) * | 2004-10-28 | 2005-06-02 | Leitch Steven D. | Method of cooking a frozen turkey |
US20080056624A1 (en) * | 2004-12-22 | 2008-03-06 | Chudley Robin W | Cooking Bags |
GB0500907D0 (en) * | 2005-01-17 | 2005-02-23 | Dupont Teijin Films Us Ltd | Self-venting polymeric film IV |
US7468498B2 (en) * | 2005-01-21 | 2008-12-23 | General Mills Marketing, Inc. | Microwavable container with sleeve |
US20060191935A1 (en) * | 2005-01-21 | 2006-08-31 | Tuszkiewicz George A | Microwavable container with sleeve |
GB0504418D0 (en) * | 2005-03-03 | 2005-04-06 | Ffp Packaging Solutions Ltd | Self-venting cover for heatable food package |
AT502142B1 (en) * | 2005-04-21 | 2007-07-15 | Mondi Packaging Ag | MICROWAVE-SUITABLE PACKAGING |
US9211030B2 (en) * | 2005-10-20 | 2015-12-15 | Conagra Foods Rdm, Inc. | Steam cooking apparatus |
US8302528B2 (en) * | 2005-10-20 | 2012-11-06 | Conagra Foods Rdm, Inc. | Cooking method and apparatus |
US8850964B2 (en) | 2005-10-20 | 2014-10-07 | Conagra Foods Rdm, Inc. | Cooking method and apparatus |
US9132951B2 (en) * | 2005-11-23 | 2015-09-15 | Conagra Foods Rdm, Inc. | Food tray |
CA2527770C (en) | 2005-11-21 | 2014-07-22 | Steven M. Parsons | Food tray |
US7770360B2 (en) * | 2005-12-05 | 2010-08-10 | Ds Smith Plastics Limited | Form fill and seal container |
SE0600306L (en) * | 2006-02-10 | 2006-12-05 | Micvac Ab | Valve system for a package |
USD636218S1 (en) | 2006-06-09 | 2011-04-19 | Conagra Foods Rdm, Inc. | Container assembly |
US20080047956A1 (en) * | 2006-08-28 | 2008-02-28 | Richard Dudman | Inductively heated warming system |
US8610039B2 (en) | 2010-09-13 | 2013-12-17 | Conagra Foods Rdm, Inc. | Vent assembly for microwave cooking package |
CA2914235C (en) * | 2007-01-08 | 2018-01-30 | Conagra Foods Rdm, Inc. | Microwave popcorn package; methods and product |
US20100015293A1 (en) * | 2007-03-02 | 2010-01-21 | Conagra Foods Rdm, Inc. | Multi-component packaging system and apparatus |
MX2009009239A (en) * | 2007-03-02 | 2009-09-08 | Conagra Foods Rdm Inc | Multi-component packaging system. |
US8613249B2 (en) * | 2007-08-03 | 2013-12-24 | Conagra Foods Rdm, Inc. | Cooking apparatus and food product |
US20090098257A1 (en) * | 2007-10-11 | 2009-04-16 | Flaherty Robert C | Self-venting microwavable packaging film; package using the film; and, methods |
US20090117323A1 (en) * | 2007-11-05 | 2009-05-07 | David Lin | Airtight Self-venting Composite Film for Food Packaging |
US20090142455A1 (en) * | 2007-11-29 | 2009-06-04 | Conagra Foods Rdm, Inc. | Dessert food package |
JP5478823B2 (en) | 2007-12-27 | 2014-04-23 | 大日本印刷株式会社 | Packaging material |
JP5162298B2 (en) * | 2008-03-27 | 2013-03-13 | 株式会社フジシールインターナショナル | Sheet-like lid for microwave processing package and microwave processing package |
US20090257687A1 (en) * | 2008-04-11 | 2009-10-15 | Birds Eye Foods, Inc. | Package fof cooking foodstuffs having high-moisture content |
US20100266732A1 (en) * | 2009-04-20 | 2010-10-21 | Fres-Co System Usa, Inc. | Microwavable self-venting package |
US20140110403A1 (en) * | 2011-05-26 | 2014-04-24 | Amcor Flexibles Transpac B.V.B.A. | Hermetically closed package to be heated in a microwave oven |
USD703547S1 (en) | 2011-06-14 | 2014-04-29 | Conagra Foods Rdm, Inc. | Microwavable bag |
USD671012S1 (en) | 2011-06-14 | 2012-11-20 | Conagra Foods Rdm, Inc. | Microwavable bag |
US8563104B1 (en) | 2012-04-02 | 2013-10-22 | Apple Inc. | Laminated roll of sealed graphite pouches and methods for making the same |
KR101194780B1 (en) * | 2012-04-17 | 2012-10-25 | 씨앤케이프로팩 (주) | Vacuum packing envelope for electronic range |
USD717162S1 (en) | 2012-06-12 | 2014-11-11 | Conagra Foods Rdm, Inc. | Container |
USD680426S1 (en) | 2012-06-12 | 2013-04-23 | Conagra Foods Rdm, Inc. | Container |
US9027825B2 (en) | 2012-06-12 | 2015-05-12 | Conagra Foods Rdm, Inc. | Container assembly and foldable container system |
EP3003902B1 (en) | 2013-05-24 | 2019-09-18 | Graphic Packaging International, LLC | Package for combined steam and microwave heating of food |
US20160152400A1 (en) * | 2014-10-30 | 2016-06-02 | LaserSharp FlexPak Services, LLC | Hermetically sealed Microwave Package and Process |
EP3229743B1 (en) | 2014-12-12 | 2020-09-30 | FastForm Research Ltd. | Multifunctional orthosis device |
WO2018015504A1 (en) * | 2016-07-21 | 2018-01-25 | Basf Se | Microwave welding of elastomer powder |
WO2018033845A1 (en) * | 2016-08-17 | 2018-02-22 | Gomes Dos Santos Antonio Alberto | Packaging for preserving preserved foodstuffs and the uses thereof in the preservation and preparation of foodstuffs |
US10358275B1 (en) | 2017-06-16 | 2019-07-23 | Plitek, L.L.C. | Pressure relief valve with a plural-part dry strap |
US11111067B2 (en) * | 2017-07-20 | 2021-09-07 | Marstonmap, Llc | Package for storing and cooking food with temperature-activated ventilation |
ES1214089Y (en) * | 2018-05-10 | 2018-09-13 | Garcia Pedro Terron | Timed valves with warning system |
EP3670340B1 (en) | 2018-12-21 | 2021-03-24 | LEONARDO S.p.A. | Aircraft |
US11352183B2 (en) | 2020-03-05 | 2022-06-07 | Plitek, L.L.C. | Pressure relief valve with wetting fluid reservoirs |
Family Cites Families (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2633284A (en) * | 1949-03-28 | 1953-03-31 | Howard J Moffett | Sealed cooking container for comestibles |
US2927722A (en) * | 1954-11-10 | 1960-03-08 | Melvin R Metzger | Vacuum type valve-equipped containers |
NL128148C (en) * | 1960-02-15 | |||
US3052554A (en) * | 1960-11-16 | 1962-09-04 | Benjamin W Colman | Popcorn package |
US3312368A (en) * | 1964-09-09 | 1967-04-04 | Reynolds Metals Co | Easy-open can end |
US3410697A (en) * | 1965-02-12 | 1968-11-12 | Brown Co | Laminated closure for food trays having heat-retractable window |
US3432087A (en) * | 1966-09-01 | 1969-03-11 | Alfred P Costello | Package valve |
US3716180A (en) * | 1970-06-01 | 1973-02-13 | Robalex Inc | Packaging |
US3672916A (en) * | 1970-08-31 | 1972-06-27 | Mass Feeding Corp | Food tray having a laminated closure that is heat-retractable |
US3941967A (en) * | 1973-09-28 | 1976-03-02 | Asahi Kasei Kogyo Kabushiki Kaisha | Microwave cooking apparatus |
US4013798A (en) * | 1973-11-21 | 1977-03-22 | Teckton, Inc. | Selectively ventable food package and micro-wave shielding device |
US4390554A (en) * | 1975-04-28 | 1983-06-28 | Levinson Melvin L | Microwave heating of certain frozen foods |
US4292332A (en) * | 1976-05-10 | 1981-09-29 | Mcham David E | Container for prepackaging, popping and serving popcorn |
US4190757A (en) * | 1976-10-08 | 1980-02-26 | The Pillsbury Company | Microwave heating package and method |
US4141487A (en) * | 1977-03-29 | 1979-02-27 | Union Carbide Corporation | Disposable food package |
US4210674A (en) * | 1978-12-20 | 1980-07-01 | American Can Company | Automatically ventable sealed food package for use in microwave ovens |
US4261504A (en) * | 1979-09-21 | 1981-04-14 | Maryland Cup Corporation | Heat-sealable, ovenable containers |
US4404241A (en) * | 1979-12-19 | 1983-09-13 | James River-Dixie/Northern, Inc. | Microwave package with vent |
US4358466A (en) * | 1980-04-11 | 1982-11-09 | The Dow Chemical Company | Freezer to microwave oven bag |
US4398077A (en) * | 1980-10-06 | 1983-08-09 | Raytheon Company | Microwave cooking utensil |
US4454403A (en) * | 1980-12-01 | 1984-06-12 | Raytheon Company | Microwave heating method and apparatus |
US4362917A (en) * | 1980-12-29 | 1982-12-07 | Raytheon Company | Ferrite heating apparatus |
US4450334A (en) * | 1981-04-24 | 1984-05-22 | Raytheon Company | Microwave pizza maker |
US4425368A (en) * | 1981-07-13 | 1984-01-10 | Golden Valley Foods Inc. | Food heating container |
US4419373A (en) * | 1982-03-29 | 1983-12-06 | American Can Company | Method of heating contents in a self venting container |
US4434197A (en) * | 1982-08-25 | 1984-02-28 | N. F. Industries, Inc. | Non-stick energy-modifying cooking liner and method of making same |
US4486640A (en) * | 1982-11-01 | 1984-12-04 | Raytheon Company | Cooker/baker utensil for microwave oven |
US4496815A (en) * | 1983-01-14 | 1985-01-29 | Northland Aluminum Products, Inc. | Microwave browning utensil |
-
1984
- 1984-09-06 US US06/647,882 patent/US4640838A/en not_active Expired - Fee Related
-
1985
- 1985-08-09 CA CA000488438A patent/CA1241701A/en not_active Expired
- 1985-08-13 AU AU46133/85A patent/AU585244B2/en not_active Ceased
- 1985-08-14 PH PH32637A patent/PH22232A/en unknown
- 1985-08-15 DK DK370985A patent/DK160932C/en not_active IP Right Cessation
- 1985-08-28 BR BR8504131A patent/BR8504131A/en not_active IP Right Cessation
- 1985-09-03 MX MX206501A patent/MX163238B/en unknown
- 1985-09-03 NO NO853470A patent/NO160702C/en unknown
- 1985-09-04 EP EP85306262A patent/EP0174188B1/en not_active Expired
- 1985-09-04 DE DE8585306262T patent/DE3571593D1/en not_active Expired
- 1985-09-05 JP JP60196858A patent/JPS6169576A/en active Granted
- 1985-09-05 ZA ZA856823A patent/ZA856823B/en unknown
- 1985-09-05 KR KR1019850006468A patent/KR930002049B1/en not_active IP Right Cessation
- 1985-09-06 AR AR85301539A patent/AR245919A1/en active
-
1989
- 1989-02-03 AU AU29624/89A patent/AU607042B2/en not_active Ceased
Also Published As
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---|---|
EP0174188A3 (en) | 1987-04-01 |
AU2962489A (en) | 1989-06-08 |
JPS6169576A (en) | 1986-04-10 |
MX163238B (en) | 1992-03-20 |
AU4613385A (en) | 1986-03-13 |
DK370985D0 (en) | 1985-08-15 |
JPH0249986B2 (en) | 1990-10-31 |
AU607042B2 (en) | 1991-02-21 |
KR930002049B1 (en) | 1993-03-22 |
AR245919A1 (en) | 1994-03-30 |
DE3571593D1 (en) | 1989-08-24 |
DK160932C (en) | 1991-11-04 |
KR860002404A (en) | 1986-04-24 |
NO160702B (en) | 1989-02-13 |
NO160702C (en) | 1989-05-24 |
DK160932B (en) | 1991-05-06 |
AU585244B2 (en) | 1989-06-15 |
EP0174188A2 (en) | 1986-03-12 |
PH22232A (en) | 1988-07-01 |
US4640838A (en) | 1987-02-03 |
BR8504131A (en) | 1986-06-17 |
ZA856823B (en) | 1987-04-29 |
DK370985A (en) | 1986-03-07 |
NO853470L (en) | 1986-03-07 |
EP0174188B1 (en) | 1989-07-19 |
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