US20050186392A1 - Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials - Google Patents

Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials Download PDF

Info

Publication number
US20050186392A1
US20050186392A1 US11/099,142 US9914205A US2005186392A1 US 20050186392 A1 US20050186392 A1 US 20050186392A1 US 9914205 A US9914205 A US 9914205A US 2005186392 A1 US2005186392 A1 US 2005186392A1
Authority
US
United States
Prior art keywords
microprojections
sheet
material according
pattern
microperforations
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.)
Abandoned
Application number
US11/099,142
Inventor
Marc Fontaine
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=8846089&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US20050186392(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Individual filed Critical Individual
Priority to US11/099,142 priority Critical patent/US20050186392A1/en
Publication of US20050186392A1 publication Critical patent/US20050186392A1/en
Priority to US12/431,383 priority patent/US8906486B2/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04FFINISHING WORK ON BUILDINGS, e.g. STAIRS, FLOORS
    • E04F13/00Coverings or linings, e.g. for walls or ceilings
    • E04F13/002Coverings or linings, e.g. for walls or ceilings made of webs, e.g. of fabrics, or wallpaper, used as coverings or linings
    • E04F13/005Stretched foil- or web-like elements attached with edge gripping devices
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26DCUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
    • B26D7/00Details of apparatus for cutting, cutting-out, stamping-out, punching, perforating, or severing by means other than cutting
    • B26D7/08Means for treating work or cutting member to facilitate cutting
    • B26D7/14Means for treating work or cutting member to facilitate cutting by tensioning the work
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26FPERFORATING; PUNCHING; CUTTING-OUT; STAMPING-OUT; SEVERING BY MEANS OTHER THAN CUTTING
    • B26F1/00Perforating; Punching; Cutting-out; Stamping-out; Apparatus therefor
    • B26F1/24Perforating by needles or pins
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84Sound-absorbing elements
    • E04B1/8409Sound-absorbing elements sheet-shaped
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B9/00Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation
    • E04B9/30Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation characterised by edge details of the ceiling; e.g. securing to an adjacent wall
    • E04B9/303Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation characterised by edge details of the ceiling; e.g. securing to an adjacent wall for flexible tensioned membranes
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84Sound-absorbing elements
    • E04B2001/8414Sound-absorbing elements with non-planar face, e.g. curved, egg-crate shaped
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84Sound-absorbing elements
    • E04B2001/8457Solid slabs or blocks
    • E04B2001/8476Solid slabs or blocks with acoustical cavities, with or without acoustical filling
    • E04B2001/848Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element
    • E04B2001/8495Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element the openings going through from one face to the other face of the element
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24273Structurally defined web or sheet [e.g., overall dimension, etc.] including aperture
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24273Structurally defined web or sheet [e.g., overall dimension, etc.] including aperture
    • Y10T428/24281Struck out portion type
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24355Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24479Structurally defined web or sheet [e.g., overall dimension, etc.] including variation in thickness
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00Cutting
    • Y10T83/04Processes
    • Y10T83/0481Puncturing

Definitions

  • the invention relates to the technical field of relatively thin sheet materials, typically less than half a millimeter thick, used for making under-ceilings, false ceilings, false walls, wall coverings, by putting such sheet materials under tension.
  • known materials for making tensioned false ceilings or tensioned false walls are usually polymer materials having numerous qualities such as the following in particular: resistance to fire; leakproof against air and also dust or moisture; and ease of cleaning.
  • False ceilings obtained using such materials can incorporate thermal insulation, spotlamps or various other kinds of lighting, and openings for ventilation or aeration or for sprinklers. Since they can be removed, they also make it possible, where appropriate, to take action in the plenum.
  • the polymer materials for tensioned ceilings that are known in the prior art can be translucent or opaque, optionally bulk colored, mat, shiny, marbled, frosted, or glazed, and can thus be used both in industrial premises and in hospitals, in public buildings, in laboratories, or in dwellings.
  • a shiny finish provides a mirror effect which is often used in commercial centers, while a mat finish similar in appearance to plaster is more usual for traditional decoration.
  • Attenuating sound reverberation on walls and ceilings is a technical problem which, as such, has been known for a long time.
  • soundproofing panels comprise a perforated plate of metal or plastics material fixed on a support of the mineral wall or polyurethane foam type.
  • Concerning this first technique whereby sound is absorbed passively by fibrous or porous materials reference can be made by way of example to the following documents: EP-A-013 513, EP-A-023 618, EP-A-246 464, EP-A-524 566, EP-A-605 784, EP-A-652 331, FR-A-2 405 818, FR-A-2 536 444, FR-A-2 544 358, FR-A-2 549 112, FR-A-2 611 776, FR-A-2 611 777, FR-A-2 732 381, U.S.
  • the panels used to form walls such as suspended ceilings are provided with cavities of volume designed to tune them to certain frequency ranges, with said cavities being protected by porous facing.
  • cavities of volume designed to tune them to certain frequency ranges, with said cavities being protected by porous facing.
  • the visible surface of the ceiling panels is embossed or provided with deep cavities or grooves.
  • a first object of the invention is to provide a flexible sheet material suitable for being used in tensioned structures for decoration, masking, or display purposes, such as false ceilings or false walls, in particular, said material presenting acoustic properties that are greatly improved.
  • a second object of the invention is to provide a material of the kind mentioned above whose visual appearance remains entirely suited to its use, whether in industrial premises or in hospitals or in public buildings or in recent or historic dwellings.
  • the invention provides a flexible sheet material of thickness less than half a millimeter for making tensioned structures such as false ceilings, in particular, the material including microprojections formed by displacing the material from which it is made, said material presenting an acoustic absorption coefficient which is higher than that of the same material without said projections.
  • this material also possesses the following characteristics, possibly in combination:
  • the invention provides a false ceiling characterized in that it comprises a sheet of material as presented above, and tensioned relative to support means.
  • FIGS. 1 a , 1 b, and 1 c show various embodiments of a material of the invention for providing a tensioned sheet
  • FIG. 5 is a graph analogous to FIG. 2 for experimental condition 10 , with the results obtained in tests 3 and 6 being plotted on the FIG. 5 graph for comparison purposes;
  • FIG. 6 is a graph analogous to FIG. 2 for experimental condition 11 , with the results obtained for conditions 4 and 5 being plotted on the FIG. 6 graph for comparison purposes;
  • FIG. 7 is a graph analogous to FIG. 2 , for experimental conditions 12 , 13 , and 14 ;
  • FIG. 8 is a histogram of sound absorption coefficient values as a function of one-third octave band frequencies for experimental conditions A;
  • FIG. 9 is a histogram analogous to FIG. 8 for experimental conditions B.
  • FIG. 10 is a histogram analogous to FIG. 8 for experimental conditions C.
  • FIG. 1 Reference is made initially to FIG. 1 .
  • FIG. 1 a is a face view of a material 1 that is about one-tenth of a millimeter thick, being provided with substantially identical microprojections 2 that are uniformly distributed in a square-mesh array.
  • FIG. 1 b is a greatly enlarged view showing the shape of such a projection 2 when seen in section perpendicular to the plane of FIG. 1 .
  • the dimensions of the micro-projections are such as to make them appear substantially as points in FIG. 1 .
  • these projections 2 are in the form of substantially circular depressions about an axis 3 perpendicular to the mean plane of the sheet of material 1 when laid out flat.
  • These projections extend over a small height h that is of the order of a few microns ( ⁇ m) to a few tens of microns, and they present a visible opening of the order of two-tenths of a millimeter.
  • these microprojections have a perforated end wall 4 .
  • these through holes 19 are the result of needling using needles whose tips have a diameter of the order of a few hundredths of a millimeter, e.g. four-hundredths of a millimeter.
  • the through holes 19 having a diameter of the order of a few hundredths of a millimeter are obtained without removing any material.
  • the end walls 4 of the perforated microprojections 2 are connected to the edges of the depressions via annular walls 5 that are bodies of revolution about the corresponding axes 3 .
  • these walls 5 can be of a thickness e 5 that is less than the thickness e 1 as measured in the sheet of material 1 away from the projections. This difference in thickness is more marked for increasing height h of the microprojections 2 , for given thickness e 1 .
  • the annular wall 5 is discontinuous.
  • the end walls of at least a fraction of the microprojections can be substantially solid, i.e. without any through holes.
  • the projections are not all identical, with two or more than two populations of different projections being provided, said projections being different in shape.
  • the projections are not all substantially in the form of points, but are elongate in at least one direction so as to form microfluting and microgrooves.
  • not all of the projections are circularly symmetrical about an axis substantially perpendicular to the mean plane of the sheet of material 1 .
  • the end walls of the depressions when seen in plan view, could be square, rectangular, oval, or in the shape of an optionally regular polygon.
  • the mesh of the array of microprojections in the embodiment shown in FIG. 1 is square. In other embodiments, the mesh need not be square but could be rectangular.
  • At least two arrays of microprojections having different meshes and/or pitches p 1 , p 2 , p′ 2 are disposed on the sheet of material 1 , as shown in FIG. 1 c.
  • the inventors have found that the visual impact of providing such projections is more or less marked, as is the impact on the acoustic properties of the sheet of material 1 , with it being possible to obtain a spectacular improvement in acoustic properties without any significant visual impact, the provision of micro-perforated microprojections turning out to be highly effective in acoustic terms and practically invisible.
  • the invention makes it possible in particular to achieve acoustic properties that are analogous to those of anti-noise suspended ceilings.
  • the sheet is provided with microprojections but is not perforated or microperforated.
  • Providing micro-projections without perforations serve to improve the acoustic properties of the material without affecting its properties as a fluid-proof barrier. Compared with perforated sheets, possible traces of air passing through such as dark marks can also be avoided. Similarly, perforations with irregular edges as obtained when the perforation tool is worn can be avoided. The material is also easy to wash.
  • microperforations 19 do not perceptibly spoil its visual appearance.
  • the inventors have found that the provision of microperforations 19 such as those shown in FIG. 1 b is practically undetectable when combined with a mat finish for the visible face 20 of the sheet of material 1 .
  • the improved acoustic properties for the material make it possible to avoid installing any fiber insulation that can give rise to dust and micro-fibers that might have harmful effects on health.
  • Soundwaves are the result of pressure variations propagating in elastic media, in the form of wave fronts at a speed that depends, in a solid, on the modulus of elasticity and on the density of the solid (being 500 meters per second (m/s) in cork and 3100 m/s in ordinary concrete, for example).
  • the spectrum audible to the human ear is formed by sound vibrations at frequencies lying in the range 16 hertz (Hz) to 20,000 Hz, providing such sounds are emitted at a sound pressure greater than a certain threshold (the threshold of audibility being equal to four phons).
  • the frequency range of speech lies in the range about 10 Hz to about 10 kHz, with speech comprehension being concentrated on frequencies lying in the range 300 Hz to 3 kHz.
  • the musical frequency range lies between about 16 Hz and 16 kHz, and one octave corresponds to a doubling in frequency.
  • Sounds can be absorbed by converting sound energy into deformation work or internal friction within a porous absorbent material having low acoustic impedance, or by using a resonator that dissipates the acoustic energy of sounds at frequencies close to the resonant frequencies of the resonator in the form of heat generated by internal friction.
  • a resonator that dissipates the acoustic energy of sounds at frequencies close to the resonant frequencies of the resonator in the form of heat generated by internal friction.
  • four types of sound insulator are distinguished:
  • a dimensionless sound absorption index a is defined such that the index a is the normalized difference between the incident and the reflected acoustic energy. This index is a function of the frequency of the incident sound.
  • the attenuation of sound in air is a function of temperature, pressure, and relative humidity, so absorption index measurements must be performed at known temperature, pressure, and humidity (see French standard NF S 30 009).
  • NF S 30 009 For standards relating to how to measure this index, reference can be made, for example, to the following documents: international standard ISO 354, French standards NF EN 20354, NF S 31 065, U.S. standard ASTM C423. The table below gives typical values of this sound absorption index a.
  • a sound reflection index p is also defined, as are a sound dissipation index 6 and a sound transmission index T.
  • Echo or reverberation due to sound being reflected on an obstacle gives rise to interference which can greatly increase the sound level in premises and make conversation difficult to follow.
  • Reverberation time is the length of time required for acoustic energy to decrease by 60 decibels (dB), i.e. to 1 part per million (ppm) compared with its initial value.
  • the sheets of material had dimensions of 9 feet by 8 feet (9′ ⁇ 8′) were fixed on the surface of a parallelepipedal box of glass wool having a wall thickness of three-quarters of an inch (3 ⁇ 4′′), and dimensions of 9′ ⁇ 8′ ⁇ 4′, the box being stood on a plate of corrugated steel.
  • the glass wool box was removed from the reverberation chamber for “empty chamber” measurements.
  • Table II is a summary of the corresponding test conditions. TABLE II Experimental conditions for the first test series Coating of Sona Spray Acoustical Glass fiber Finish from K13 from Owens Test Type of Spray-On Coming number sheet Support Systems on steel sheet 1b Smooth Steel plate No No 2b Smooth Steel plate No 6′′ R19 3 Perforated Steel plate No 6′′ R19 NLM41 4 Perforated Steel plate No 6′′ R19 NL601 5 Perforated Steel plate 1′′ No NL601 6 Perforated Steel plate 1′′ No NLM41 7 Smooth Steel plate 1′′ No 8 Smooth — No 6′′ R19, at 3′′ from the sheet 8b Smooth — No 37 ⁇ 8′′ RA24 (1.5#) at 5.75′′ from the sheet 9 Smooth Steel plate 2.25′′ No 10 Perforated Steel plate 2.25′′ No NLM41 11 Perforated Steel plate 2.25′′ No NL601
  • the “perforated NLM41” sheets were of the type sold by the Applicant under the reference NewLine NLM41. Those sheets have perforations of large dimensions (circular holes with a diameter of 4 mm), obtained by removing material, with the density of the holes being less than 1 per square centimeter. The circular holes are to enable the plenum to be ventilated and smoke, if any, to be removed: this range of NLM41 products has the N1/B1/Fire 1 classification.
  • the “perforated NL601” sheets were of the type sold by the Applicant under the reference NewLine NL601. Those sheets are likewise provided with perforations of large size (circular holes having a diameter of 1 millimeter), which perforations are obtained by removing material. Like the holes in NLM41 sheets, these circular holes are intended to enable the plenum to be ventilated and any smoke to be removed, this NL601 range of products having the M1/B1/Fire 1 classification.
  • FIG. 2 gives the results for tests 1 b, 2 b, 3 , 4 compared with five values obtained with a reference;
  • FIG. 3 gives the results for tests 5 , 6 , and 7 relative to said reference
  • FIG. 4 is a graph combining the results of tests 8 , 8 b, and 9 , compared with those obtained in tests 1 b, 2 b, and 7 ;
  • FIG. 5 is a graph showing the results obtained for test 10 , as compared with tests 3 and 6 ;
  • FIG. 6 is a graph showing the results obtained for test 11 , compared with those obtained for tests 4 and 5 .
  • Comparing curves 1 b and 2 b shows the impact of installing conventional fiber acoustic insulation, as can be done in the plenum.
  • the sheets of tensioned material can vibrate so they are therefore neither rigid nor undeformable, and in addition the thickness h is very small compared with the thickness of acoustic insulating panels, such that the above model is not suitable.
  • Other models known in the field of acoustics seek to predict the behavior of panels comprising perforated diaphragms, taking account of the stiffness specific to the panel and the compression of the air behind the panel, and also how air flows through the perforations since that can have a dissipating effect.
  • Curves 5 , 6 , and 7 illustrate the impact of using a spray acoustical finish on the tensioned sheets. The effect of this finish is particularly marked at high frequencies.
  • FIG. 4 for a smooth tensioned sheet, installing fibrous insulation (tests 2 b, 8 , 8 b ) or applying a spray acoustical finish (tests 7 and 9 ) gives results at frequencies above 400 Hz that are inferior to those obtained using perforated sheets with or without a spray acoustical finish.
  • the acoustic attenuation properties are highly asymmetrical below low frequencies and high frequencies.
  • micro-perforated is used herein, with reference to tests 12 , 13 , and 14 , to mean a sheet of PVC material having a thickness of 17 hundredths of a millimeter and provided with microperforations formed by needling, without removing any material, the needles used have a tip diameter of about 4 hundredths of a millimeter, the density of the resulting microperforations being about twenty-three per square centimeter, the perforations being distributed in a mesh of the kind shown in FIG. 1 a.
  • the sheet was tensioned on the top face of an unpainted parallelepipedal box having a 3 ⁇ 4′′ thick wall of glass fibers, and a volume of 10,154.72 cubic feet (cu.ft).
  • the “empty chamber” results were obtained without using the box, the sheet of material being placed on a steel plate.
  • the values T60 correspond to average reverberation times.
  • the acoustic absorption coefficient (AAC) and the results were obtained in application of United States standard ASTM C423-90a.
  • the noise reduction coefficient (NRC) and AAC values were obtained in application of the standard ASTM C423.
  • a 6′′ thick layer of glass wool R19 from Owens Corning was suspended in the box, at 3.75′′ from the sheet of tensioned material.
  • a 1′′ thick layer of RA24 glass fiber from Owens Corning was suspended in the box at 8.75′′ from the sheet of tensioned material.
  • the acoustic absorption values obtained during tests 12 , 13 , and 14 are plotted on the graph of FIG. 7 , with only frequencies lying in the range 125 Hz to 4000 Hz being taken into account so as to make them comparable with the presentation of the graphs of FIGS. 2 to 6 .
  • Those frames constituted supports for tips of smooth tensioned PVC material.
  • the frame supporting the smooth PVC panels was of metal tubes having a height of 4′′ and a nominal thickness of 11 ⁇ 2′′.
  • the frame was fixed on the outside to the base wall of the reverberation chamber.
  • a 2′′ thick glass fiber panel (density 3 lb/cu.ft) was placed directly on the end wall of the chamber.
  • the total weight of the glass fiber panel was 0.49 psf, with the PVC strip weighing 0.05 psf.
  • 8′ ⁇ 9′ panels of smooth (5 mil) PVC were placed using a barb/rail mount at 4′′ from the end wall of the reverberation chamber (E90 setup of the standard ASTM E 795).
  • the support frame for the smooth PVC panels was made of metal tubes having a height of 4′′ and a nominal thickness of 11 ⁇ 2′′.
  • the frame was fixed on the outside to the base wall of the reverberation chamber.
  • a 1′′ thick (density 3 lb/cu.ft) glass fiber panel was placed directly on the end wall of the chamber.
  • the total weight of the glass fiber panel was 0.25 psf, the PVC strip weighing 0.05 psf.
  • NRC and mean NRC values obtained for tests A, B, C are given in Table VI below. TABLE VI NRC values obtained for tests A, B, and C Test A Test B Test C NRC Moyen 0.65 0.633 0.455 NRC 0.65 0.65 0.45
  • FIGS. 8, 9 , and 10 show how the acoustic absorption coefficients vary with frequency for frequencies lying in the range 100 Hz to 5000 Hz for tests A, B, and C.
  • the flexible sheet polymer material having improved acoustic properties as described above is suitable for use in tensioned decorative or masking structures, such as those constituting false ceilings or false walls, in particular.
  • the material can also be used for display panels, whether of the fixed type or of the moving type, with the attenuation in reverberation making it possible to reduce the sound nuisance that is generated by such panels.
  • the material Since the visual appearance of the material is not significantly altered by making the microprojections, the material remains entirely suited for use in industrial premises and in hospitals, and also for use in public buildings or in recent or historic dwellings.

Abstract

A flexible sheet material of thickness less than half a millimeter for making tensioned structures such as false ceilings, in particular, the material including microprojections formed by displacing the material from which it is made, said material presenting an acoustic absorption coefficient which is higher than that of the same material without said projections.

Description

  • The invention relates to the technical field of relatively thin sheet materials, typically less than half a millimeter thick, used for making under-ceilings, false ceilings, false walls, wall coverings, by putting such sheet materials under tension.
  • A large number of embodiments of such materials and also the use thereof in tensioned or “stretched” false ceilings are already known in the prior art.
  • By way of example, reference can be made to the patent applications made in France published under the following numbers: 2 767 851, 2 751 682, 2 734 296, 2 712 006, 2 707 708, 2 703 711, 2 699 211, 2 699 209, 2 695 670, 2 691 193, 2 685 036, 2 645 135, 2 630 476, 2 627 207, 2 624 167, 2 623 540, 2 619 531, 2 597 906, 2 611 779, 2 592 416, 2 587 447, 2 561 690, 2 587 392, 2 552 473, 2 537 112, 2 531 012, 2 524 922, 2 475 093, 2 486 127, 2 523 622, 2 310 450, 2 270 407, 2 202 997, 2 175 854, 2 145 147, 2 106 407, 2 002 261, 1 475 446, 1 303 930, 1 287 077. Reference can also be made, by way of example, to the following documents: U.S. Pat. No. 5,058,340, U.S. Pat. No. 4,083,157, EP-A-643 180, EP-A-652 339, EP-A-588 748, EP-A-504 530, EP-A-338 925, EP-A-281 468, EP-A-215 715, EP-A-089 905, EP-A-043 466, WO-A-94/12741, WO-A-92/18722. Reference can also be made to the following French patent applications stemming from the Applicant: 2 736 615, 2 756 600, 2 727 711, 2 712 325, 2 699 613, 2 695 670, 2 692 302, 2 658 849.
  • In the prior art, known materials for making tensioned false ceilings or tensioned false walls are usually polymer materials having numerous qualities such as the following in particular: resistance to fire; leakproof against air and also dust or moisture; and ease of cleaning.
  • False ceilings obtained using such materials can incorporate thermal insulation, spotlamps or various other kinds of lighting, and openings for ventilation or aeration or for sprinklers. Since they can be removed, they also make it possible, where appropriate, to take action in the plenum.
  • The polymer materials for tensioned ceilings that are known in the prior art can be translucent or opaque, optionally bulk colored, mat, shiny, marbled, frosted, or glazed, and can thus be used both in industrial premises and in hospitals, in public buildings, in laboratories, or in dwellings.
  • A shiny finish provides a mirror effect which is often used in commercial centers, while a mat finish similar in appearance to plaster is more usual for traditional decoration.
  • In spite of the numerous advantages that have led to increasing use of prior art tensioned polymer sheet false ceilings and false walls in a variety of environments, they suffer from the major drawback of presenting poor acoustic properties, with the reverberation of sound on such tensioned ceilings being particularly high.
  • Attenuating sound reverberation on walls and ceilings is a technical problem which, as such, has been known for a long time.
  • Several technical solutions have been envisaged.
  • In a first technique, soundproofing panels comprise a perforated plate of metal or plastics material fixed on a support of the mineral wall or polyurethane foam type. Concerning this first technique whereby sound is absorbed passively by fibrous or porous materials, reference can be made by way of example to the following documents: EP-A-013 513, EP-A-023 618, EP-A-246 464, EP-A-524 566, EP-A-605 784, EP-A-652 331, FR-A-2 405 818, FR-A-2 536 444, FR-A-2 544 358, FR-A-2 549 112, FR-A-2 611 776, FR-A-2 611 777, FR-A-2 732 381, U.S. Pat. No. 4,441,580, U.S. Pat. No. 3,948,347. That technique leads to an assembly in which the acoustically absorbent backing is secured to the visible perforated facing. The perforations are intended to allow waves to be attenuated by the acoustically absorbent material which cannot be left visible because it is too fragile, has a surface that is sometimes easily dirtied, and has raw appearance that is unattractive.
  • In a second technique, the panels used to form walls such as suspended ceilings, for example, are provided with cavities of volume designed to tune them to certain frequency ranges, with said cavities being protected by porous facing. For that second type of technique using Helmholtz resonators, reference can be made for example to the following documents: DE-PS-36 43 481, FR-A-2 463 235.
  • In a third technique which is used in the field of suspended ceilings, the visible surface of the ceiling panels is embossed or provided with deep cavities or grooves. By way of example, reference can be made to the following documents: FR-A-2 381 142, FR-A-2 523 621, FR-A-2 573 798, WO-A-80/01 183, WO-A-94/24382.
  • In a fourth technique, honeycomb sheets form absorbing membranes. That technique is expensive, but is sometimes used in recording studios.
  • None of the technical solutions known in the prior art for improving the sound properties of suspended ceilings or walls is suitable for the particular technique of tensioned walls or ceilings.
  • A first object of the invention is to provide a flexible sheet material suitable for being used in tensioned structures for decoration, masking, or display purposes, such as false ceilings or false walls, in particular, said material presenting acoustic properties that are greatly improved.
  • A second object of the invention is to provide a material of the kind mentioned above whose visual appearance remains entirely suited to its use, whether in industrial premises or in hospitals or in public buildings or in recent or historic dwellings.
  • To these ends, in a first aspect the invention provides a flexible sheet material of thickness less than half a millimeter for making tensioned structures such as false ceilings, in particular, the material including microprojections formed by displacing the material from which it is made, said material presenting an acoustic absorption coefficient which is higher than that of the same material without said projections.
  • In various embodiments, this material also possesses the following characteristics, possibly in combination:
      • the height of the microprojections measured in a direction perpendicular to the plane of said sheet in the vicinity of said microprojections is less than three times the thickness of said sheet;
      • the microprojections project on one side only of said sheet;
      • each of the microprojections is located at a node of a regular pattern;
      • all of the microprojections are located at the nodes of a single pattern, e.g. having a square mesh;
      • its microprojections project from both faces of said sheet, each of the microprojections being disposed at a node of a regular pattern, and, where appropriate, all of the microprojections being disposed at the nodes of a single pattern, e.g. a square mesh;
      • the microprojections are in the form of depressions having a substantially plane end wall connected to an opening via a strip of material of thickness that is smaller than or equal to the thickness of portions of the sheet between the microprojections;
      • the depressions are circularly symmetrical about respective axes that are substantially perpendicular to their end walls;
      • the strip of material connecting the end wall of a depression to its opening is discontinuous;
      • it is provided with microperforations, having openings smaller than four-tenths of a millimeter (0.4 mm);
      • the material is provided with microperforations, having openings smaller than four-tenths of a millimeter, at least a fraction of the microprojections being provided with said microperforations, said micro-perforations being, where appropriate, likewise disposed between the microprojections;
      • the microperforations are disposed at the nodes of a pattern;
      • the microperforations are disposed at the nodes of a pattern identical to the pattern of the micro-projections and offset relative thereto;
      • the microperforations are obtained by needling or by any other equivalent method;
      • the microperforations are obtained without removing any material;
      • the material is selected from the group comprising plastified polyvinyl chlorides, vinylidene chlorides, copolymers of vinyl chloride and vinylidene chloride, and any other equivalent material;
      • the area occupied by the microprojections lies in the range 0.5% to 10% of the area of said sheet; and
      • the density of the microprojections and/or the microperforations lies in the range 2 to 60 per square centimeter, preferably in the range 15 to 35 per square centimeter, and more particularly in the range 20 to 30 per square centimeter.
  • In a second aspect, the invention also provides a method of making a sheet of material as presented above, the method comprising a step of needling to displace locally the material constituting the sheet so as to subject it to microperforation in a predetermined pattern. The needling step is performed without any material being removed from the sheet. The needles used in the needling method have a tip diameter of less than one-tenth of a millimeter, for example of the order of four-hundredths of a millimeter. In an implementation, the needling is performed while the sheet of material is subjected to tension of the same order as the tension to which it will be subjected in final use in a tensioned structure.
  • In a third aspect, the invention provides a false ceiling characterized in that it comprises a sheet of material as presented above, and tensioned relative to support means.
  • Other objects and advantages of the invention appear from the following description of embodiments, which description is given with reference to the accompanying drawings, in which:
  • FIGS. 1 a, 1 b, and 1 c show various embodiments of a material of the invention for providing a tensioned sheet;
  • FIG. 2 is a graph showing measured values for the acoustic absorption coefficient as a function of one-third octave band center frequencies under four experimental conditions 1 b, 2 b, 3, and 4, and also for a reference sample;
  • FIG. 3 is a graph analogous to FIG. 2 for experimental conditions 5, 6, and 7;
  • FIG. 4 is a graph analogous to FIG. 3 for experimental conditions 8, 8 b, and 9, with the results obtained for conditions 1 b and 2 b being plotted on the FIG. 4 graph for comparison purposes;
  • FIG. 5 is a graph analogous to FIG. 2 for experimental condition 10, with the results obtained in tests 3 and 6 being plotted on the FIG. 5 graph for comparison purposes;
  • FIG. 6 is a graph analogous to FIG. 2 for experimental condition 11, with the results obtained for conditions 4 and 5 being plotted on the FIG. 6 graph for comparison purposes;
  • FIG. 7 is a graph analogous to FIG. 2, for experimental conditions 12, 13, and 14;
  • FIG. 8 is a histogram of sound absorption coefficient values as a function of one-third octave band frequencies for experimental conditions A;
  • FIG. 9 is a histogram analogous to FIG. 8 for experimental conditions B; and
  • FIG. 10 is a histogram analogous to FIG. 8 for experimental conditions C.
  • Reference is made initially to FIG. 1.
  • FIG. 1 a is a face view of a material 1 that is about one-tenth of a millimeter thick, being provided with substantially identical microprojections 2 that are uniformly distributed in a square-mesh array. FIG. 1 b is a greatly enlarged view showing the shape of such a projection 2 when seen in section perpendicular to the plane of FIG. 1. The dimensions of the micro-projections are such as to make them appear substantially as points in FIG. 1. In the embodiment shown here, these projections 2 are in the form of substantially circular depressions about an axis 3 perpendicular to the mean plane of the sheet of material 1 when laid out flat. These projections extend over a small height h that is of the order of a few microns (μm) to a few tens of microns, and they present a visible opening of the order of two-tenths of a millimeter.
  • In the embodiment shown, these microprojections have a perforated end wall 4. In a particular embodiment, these through holes 19 are the result of needling using needles whose tips have a diameter of the order of a few hundredths of a millimeter, e.g. four-hundredths of a millimeter.
  • In an implementation, the needling is performed while the sheet of material 1 is placed under tension. In a particular implementation, this tension is of the same order as that to which the sheet is subjected in use, e.g. as a tensioned false ceiling.
  • The through holes 19 having a diameter of the order of a few hundredths of a millimeter are obtained without removing any material.
  • The end walls 4 of the perforated microprojections 2 are connected to the edges of the depressions via annular walls 5 that are bodies of revolution about the corresponding axes 3. Where appropriate, these walls 5 can be of a thickness e5 that is less than the thickness e1 as measured in the sheet of material 1 away from the projections. This difference in thickness is more marked for increasing height h of the microprojections 2, for given thickness e1.
  • In certain particular embodiments (not shown) for at least a fraction of the projections 2, the annular wall 5 is discontinuous.
  • In a variant, the end walls of at least a fraction of the microprojections can be substantially solid, i.e. without any through holes.
  • By way of example, the following values can be implemented:
      • pitch p between microprojections: 1 mm;
      • density of microprojections per square centimeter (cm2): 25; and
      • height of projections: a few microns to 100 μm.
  • Other embodiments could be envisaged.
  • In a first type of variant, the projections are not all identical, with two or more than two populations of different projections being provided, said projections being different in shape.
  • In a second type of variant, possibly combined with the first type mentioned above, the projections are not all substantially in the form of points, but are elongate in at least one direction so as to form microfluting and microgrooves.
  • In a third type of variant, possibly combined with one or both of the above types, not all of the projections are circularly symmetrical about an axis substantially perpendicular to the mean plane of the sheet of material 1.
  • Thus, for example, the end walls of the depressions, when seen in plan view, could be square, rectangular, oval, or in the shape of an optionally regular polygon. The mesh of the array of microprojections in the embodiment shown in FIG. 1 is square. In other embodiments, the mesh need not be square but could be rectangular.
  • In certain embodiments, at least two arrays of microprojections having different meshes and/or pitches p1, p2, p′2 are disposed on the sheet of material 1, as shown in FIG. 1 c.
  • Depending on the density of the microprojections, the pattern in which they are distributed, and their height, the inventors have found that the visual impact of providing such projections is more or less marked, as is the impact on the acoustic properties of the sheet of material 1, with it being possible to obtain a spectacular improvement in acoustic properties without any significant visual impact, the provision of micro-perforated microprojections turning out to be highly effective in acoustic terms and practically invisible. Thus while maintaining conventional appearance for the tensioned sheet, making it clearly different from suspended ceilings that are perforated or gridded, the invention makes it possible in particular to achieve acoustic properties that are analogous to those of anti-noise suspended ceilings.
  • In certain embodiments, as mentioned above, the sheet is provided with microprojections but is not perforated or microperforated. Providing micro-projections without perforations serve to improve the acoustic properties of the material without affecting its properties as a fluid-proof barrier. Compared with perforated sheets, possible traces of air passing through such as dark marks can also be avoided. Similarly, perforations with irregular edges as obtained when the perforation tool is worn can be avoided. The material is also easy to wash.
  • When a sheet of material provided with micro-perforations is seen looking along arrow F in FIG. 1 b, the microperforations 19 do not perceptibly spoil its visual appearance. In particular, the inventors have found that the provision of microperforations 19 such as those shown in FIG. 1 b is practically undetectable when combined with a mat finish for the visible face 20 of the sheet of material 1. The improved acoustic properties for the material make it possible to avoid installing any fiber insulation that can give rise to dust and micro-fibers that might have harmful effects on health.
  • The improvement obtained in the acoustic properties of sheets of material by providing microperforated micro-projections is illustrated below with the help of various experimental results. In order to present these results, the following elements of acoustics need to be recalled insofar as these elements are not part of the knowledge of the person skilled in the art of tensioned sheet walls and ceilings.
  • Soundwaves are the result of pressure variations propagating in elastic media, in the form of wave fronts at a speed that depends, in a solid, on the modulus of elasticity and on the density of the solid (being 500 meters per second (m/s) in cork and 3100 m/s in ordinary concrete, for example). The spectrum audible to the human ear is formed by sound vibrations at frequencies lying in the range 16 hertz (Hz) to 20,000 Hz, providing such sounds are emitted at a sound pressure greater than a certain threshold (the threshold of audibility being equal to four phons). The frequency range of speech lies in the range about 10 Hz to about 10 kHz, with speech comprehension being concentrated on frequencies lying in the range 300 Hz to 3 kHz. The musical frequency range lies between about 16 Hz and 16 kHz, and one octave corresponds to a doubling in frequency.
    Instrument or voice Low frequency (Hz) High frequency (Hz)
    Violin 200 3000
    Piano 30 4000
    Flute 250 2500
    Cello 70 800
    Double bass 40 300
    Tuba 50 400
    Trumpet 200 1000
    Organ 16 1600
    Bass 100 350
    Baritone 150 400
    Tenor 150 500
    Alto 200 800
    Soprano 250 1200
  • Sounds can be absorbed by converting sound energy into deformation work or internal friction within a porous absorbent material having low acoustic impedance, or by using a resonator that dissipates the acoustic energy of sounds at frequencies close to the resonant frequencies of the resonator in the form of heat generated by internal friction. In conventional manner, four types of sound insulator are distinguished:
      • rigid porous materials such as porous concretes and rigid foams, in which the capillary networks provide acoustic resistance;
      • elastic porous materials such as minerals wools, felts, polystyrenes, in which acoustic energy is dissipated by solid friction;
      • materials exhibiting acoustic resonance, acting on the principle of Helmholtz resonators, such as perforated panels; and
      • materials presenting mechanical resonance, operating on the basis of a damped oscillator.
  • A dimensionless sound absorption index a is defined such that the index a is the normalized difference between the incident and the reflected acoustic energy. This index is a function of the frequency of the incident sound. The attenuation of sound in air is a function of temperature, pressure, and relative humidity, so absorption index measurements must be performed at known temperature, pressure, and humidity (see French standard NF S 30 009). For standards relating to how to measure this index, reference can be made, for example, to the following documents: international standard ISO 354, French standards NF EN 20354, NF S 31 065, U.S. standard ASTM C423. The table below gives typical values of this sound absorption index a.
    α α α
    at 125 Hz at 500 Hz at 2000 Hz
    Rendering on masonry 0.02 0.02 0.03
    Lime rendering 0.03 0.03 0.04
    Lightweight concrete 0.07 0.22 0.10
    Mortar 0.03 0.03 0.07
    2.5 cm thick acoustic plate
    with 3 cm of air; 0.25 0.23 0.74
    applied against a wall 0.15 0.23 0.73
    2 cm thick insulating panels
    applied
    against a wall 0.13 0.19 0.24
    with 3 cm of air 0.15 0.23 0.23
    with 3 cm of glass wool 0.33 0.44 0.37
    Wooden door 0.14 0.06 0.10
    Wooden flooring 0.05 0.06 0.10
    3 mm thick plywood plus 2 cm of 0.07 0.22 0.10
    air
    3 mm thick plywood on a wall 0.07 0.05 0.10
  • In similar manner, a sound reflection index p is also defined, as are a sound dissipation index 6 and a sound transmission index T.
  • At the interface between two media, the principle of sound energy conservation means that:
    ρ+τ+δ=1, ρ+α=1
  • The greater the amount of acoustic energy dissipated by an acoustic insulator, the smaller the amount of acoustic energy that is reflected, thereby reducing the echo effect.
  • Echo or reverberation due to sound being reflected on an obstacle gives rise to interference which can greatly increase the sound level in premises and make conversation difficult to follow.
  • For such reverberation, a reverberation time T is defined using the Sabine formula:
    T=0.163 V/αA
    where V is the volume of empty space; A is the absorbing area; and α is the absorption index as defined above.
  • The Sabine formula is established on the basis of the assumption that the reverberating field is distributed entirely uniformly. Reverberation time is the length of time required for acoustic energy to decrease by 60 decibels (dB), i.e. to 1 part per million (ppm) compared with its initial value.
  • Now that these notions of acoustics have been summarized, there follow various experimental results obtained under standardized conditions.
  • In a first series of tests, twelve strips of material were subjected to acoustic absorption testing.
  • The sheets of material had dimensions of 9 feet by 8 feet (9′×8′) were fixed on the surface of a parallelepipedal box of glass wool having a wall thickness of three-quarters of an inch (¾″), and dimensions of 9′×8′×4′, the box being stood on a plate of corrugated steel.
  • The glass wool box was removed from the reverberation chamber for “empty chamber” measurements.
  • The results of the tests are given in Table I below.
  • The frequencies given in Table I are the standardized one-third octave band center frequencies.
    TABLE I
    First test series
    Frequencies
    (Hz) Test 1b Test 2b Test 3 Test 4 Test 5 Test 6 Test 7 Test 8 Test 9 Test 10 Test 11 Test 8b
    125 0.43 0.71 0.77 0.77 0.37 0.43 0.47 0.80 0.46 0.33 0.42 0.90
    160 0.31 0.70 0.68 0.60 0.43 0.45 0.49 0.97 0.59 0.61 0.59 1.01
    200 0.18 0.69 0.69 0.66 0.41 0.41 0.40 0.89 0.42 0.49 0.55 0.93
    250 0.21 0.63 0.73 0.72 0.49 0.51 0.43 0.88 0.51 0.63 0.61 0.97
    315 0.29 0.79 0.87 0.88 0.68 0.73 0.65 0.90 0.70 0.79 0.75 0.94
    400 0.39 0.87 1.00 1.03 0.81 0.83 0.70 0.82 0.76 0.83 0.83 0.76
    500 0.41 0.82 1.02 1.03 0.82 0.85 0.70 0.75 0.74 0.92 0.93 0.69
    630 0.39 0.73 0.98 0.99 0.87 0.87 0.68 0.69 0.69 0.91 0.90 0.65
    800 0.37 0.69 1.00 1.00 0.93 0.93 0.67 0.68 0.68 0.94 0.93 0.67
    1000 0.34 0.61 1.01 1.00 0.97 0.99 0.61 0.63 0.60 0.95 0.93 0.67
    1250 0.35 0.58 1.06 1.06 1.02 1.04 0.59 0.61 0.57 1.01 1.00 0.62
    1600 0.37 0.56 1.09 1.09 1.05 1.07 0.54 0.57 0.53 1.02 1.00 0.59
    2000 0.35 0.48 1.08 1.04 1.07 1.07 0.50 0.50 0.44 0.97 0.97 0.52
    2500 0.34 0.43 1.07 1.01 1.07 1.07 0.44 0.43 0.34 0.91 0.88 0.49
    3150 0.30 0.36 1.01 0.91 1.01 1.01 0.38 0.36 0.24 0.76 0.70 0.45
    4000 0.27 0.32 0.93 0.78 0.97 0.98 0.37 0.33 0.10 0.57 0.46 0.43
    AAC 0.35 0.65 0.95 0.95 0.85 0.85 0.55 0.70 0.55 0.85 0.85 0.70
  • Table II is a summary of the corresponding test conditions.
    TABLE II
    Experimental conditions for the first test
    series
    Coating of Sona
    Spray Acoustical Glass fiber
    Finish from K13 from Owens
    Test Type of Spray-On Coming
    number sheet Support Systems on steel sheet
     1b Smooth Steel plate No No
     2b Smooth Steel plate No 6″ R19
     3 Perforated Steel plate No 6″ R19
    NLM41
     4 Perforated Steel plate No 6″ R19
    NL601
     5 Perforated Steel plate 1″ No
    NL601
     6 Perforated Steel plate 1″ No
    NLM41
     7 Smooth Steel plate 1″ No
     8 Smooth No 6″ R19,
    at 3″ from the sheet
     8b Smooth No 3⅞″ RA24
    (1.5#) at 5.75″
    from the sheet
     9 Smooth Steel plate  2.25″ No
    10 Perforated Steel plate  2.25″ No
    NLM41
    11 Perforated Steel plate  2.25″ No
    NL601
  • The “perforated NLM41” sheets were of the type sold by the Applicant under the reference NewLine NLM41. Those sheets have perforations of large dimensions (circular holes with a diameter of 4 mm), obtained by removing material, with the density of the holes being less than 1 per square centimeter. The circular holes are to enable the plenum to be ventilated and smoke, if any, to be removed: this range of NLM41 products has the N1/B1/Fire 1 classification.
  • The “perforated NL601” sheets were of the type sold by the Applicant under the reference NewLine NL601. Those sheets are likewise provided with perforations of large size (circular holes having a diameter of 1 millimeter), which perforations are obtained by removing material. Like the holes in NLM41 sheets, these circular holes are intended to enable the plenum to be ventilated and any smoke to be removed, this NL601 range of products having the M1/B1/Fire 1 classification.
  • Curves corresponding to the above results are given in FIGS. 2 to 7:
  • FIG. 2 gives the results for tests 1 b, 2 b, 3, 4 compared with five values obtained with a reference;
  • FIG. 3 gives the results for tests 5, 6, and 7 relative to said reference;
  • FIG. 4 is a graph combining the results of tests 8, 8 b, and 9, compared with those obtained in tests 1 b, 2 b, and 7;
  • FIG. 5 is a graph showing the results obtained for test 10, as compared with tests 3 and 6; and
  • FIG. 6 is a graph showing the results obtained for test 11, compared with those obtained for tests 4 and 5.
  • Comparing curves 1 b and 2 b shows the impact of installing conventional fiber acoustic insulation, as can be done in the plenum.
  • Comparing curves 3 and 4 with curves 1 b and 2 b shows that perforating the tensioned sheet serves to increase the acoustic absorption properties thereof, in particular at high frequencies, a range in which installing fiber insulation turns out to have little effect. The inventors have sought an explanation for this observation. It turns out that in acoustics, it is known that a rigid perforated panel of thickness h situated at a distance e from a wall and having n cylindrical perforations of radius a, said panel being supported by four orthogonal battens, presents maximum effectiveness at an angular frequency given by:
    ω=c(nπ/a 2 e(h+8a/3π))½
    the panel behaving like a set of Helmholtz resonators with its maximum acoustic absorption value depending on the value of the damping coefficient and the perforation density. That type of mechanism is used in perforated suspended ceilings.
  • With the tensioned sheets under consideration herein, the sheets of tensioned material can vibrate so they are therefore neither rigid nor undeformable, and in addition the thickness h is very small compared with the thickness of acoustic insulating panels, such that the above model is not suitable. Other models known in the field of acoustics seek to predict the behavior of panels comprising perforated diaphragms, taking account of the stiffness specific to the panel and the compression of the air behind the panel, and also how air flows through the perforations since that can have a dissipating effect.
  • Those highly complex models might possibly apply to the results obtained during steps 3, 4, 5, 6, 10, and 11.
  • Curves 5, 6, and 7 illustrate the impact of using a spray acoustical finish on the tensioned sheets. The effect of this finish is particularly marked at high frequencies. Conversely, as shown in FIG. 4, for a smooth tensioned sheet, installing fibrous insulation ( tests 2 b, 8, 8 b) or applying a spray acoustical finish (tests 7 and 9) gives results at frequencies above 400 Hz that are inferior to those obtained using perforated sheets with or without a spray acoustical finish. In all of the configurations shown by tests 1 b, 2 b, 3, 4, 5, 6, 7, 8, 8 b, 9, 10, and 11, the acoustic attenuation properties are highly asymmetrical below low frequencies and high frequencies.
  • Unexpectedly, and without being able to give any simple explanation, the inventors have found that making microprojections and microperforations gives rise to results that are just as favorable as making perforations of large size. Indeed, the results obtained with micro-perforations are better in the high frequency range than those obtained with perforations of large size.
  • Tests 12, 13, and 14 illustrate these surprising results. Test conditions were as follows: temperature=70° F. (about 21.2° C.), humidity=64%, pressure=atmospheric. A 9′×8′ microperforated sheet of material was tested in an E 1219 type setup. The term “micro-perforated” is used herein, with reference to tests 12, 13, and 14, to mean a sheet of PVC material having a thickness of 17 hundredths of a millimeter and provided with microperforations formed by needling, without removing any material, the needles used have a tip diameter of about 4 hundredths of a millimeter, the density of the resulting microperforations being about twenty-three per square centimeter, the perforations being distributed in a mesh of the kind shown in FIG. 1 a. The sheet was tensioned on the top face of an unpainted parallelepipedal box having a ¾″ thick wall of glass fibers, and a volume of 10,154.72 cubic feet (cu.ft). The “empty chamber” results were obtained without using the box, the sheet of material being placed on a steel plate. For empty chamber testing, the values T60 correspond to average reverberation times. The acoustic absorption coefficient (AAC) and the results were obtained in application of United States standard ASTM C423-90a. The noise reduction coefficient (NRC) and AAC values were obtained in application of the standard ASTM C423. For test 12, a 6″ thick layer of glass wool R19 from Owens Corning was suspended in the box, at 3.75″ from the sheet of tensioned material. For test 13, a 1″ thick layer of RA24 glass fiber from Owens Corning was suspended in the box at 8.75″ from the sheet of tensioned material. For test 14, no material was placed in the box.
    TABLE III
    Tests Nos. 12, 13, and 14.
    Acoustic absorption measurements using a reverberation chamber
    Test Test Test
    Empty 14 Margin 13 Margin 12 Margin
    chamber T60 sabins/ T60 sabins/ T60 sabins/
    Freq.. (Hz) T60 (s) Uncert. % (s) Uncert. % AAC sq. ft (s) Uncert. % AAC Sq. ft (s) Uncert. % AAC Sq. ft
    50 1.63 5 1.31 3.23 0.76 0.26 1.37 2.59 0.52 0.26 1.88 15.29 0.84 0.61
    63 1.37 7.56 0.96 4.48 2.15 0.50 0.90 3.25 2.59 0.46 1.01 4.61 1.80 0.50
    80 1.60 5.44 1.17 14.97 1.61 0.92 1.12 6.42 1.88 0.48 1.15 4.52 1.71 0.36
    100 2.40 5.74 2.21 6.64 0.24 0.32 1.96 9.18 0.64 0.36 1.70 2.44 1.17 0.19
    125 3.16 2.37 2.81 3.90 0.27 0.11 2.57 3.86 0.51 0.12 2.37 2.67 0.73 0.09
    160 3.56 3.22 3.06 1.99 0.32 0.08 2.63 1.95 0.69 0.08 2.56 4.01 0.76 0.13
    200 4.01 2.53 3.55 2.31 0.22 0.06 2.94 2.38 0.63 0.07 2.58 2.07 0.96 0.07
    250 5.62 1.34 4.37 2.16 0.35 0.04 3.45 2.53 0.77 0.05 3.18 2.06 0.94 0.05
    315 6.67 1.77 5.02 1.43 0.34 0.03 3.81 1.58 0.78 0.03 3.54 1.19 0.91 0.03
    400 6.25 0.90 4.53 1.65 0.42 0.03 3.64 1.62 0.80 0.03 3.39 1.77 0.93 0.04
    500 7.05 0.62 4.82 1.08 0.45 0.03 3.93 1.28 0.78 0.02 3.85 1.43 0.81 0.03
    630 7.23 0.73 4.85 1.29 0.47 0.02 3.99 1.44 0.78 0.03 3.95 1.43 0.79 0.03
    800 7.23 0.41 4.65 1.01 0.53 0.02 3.89 0.71 0.82 0.01 3.87 0.84 0.83 0.02
    1000 7.17 0.45 4.47 1.06 0.58 0.02 3.85 0.59 0.83 0.01 3.88 0.93 0.82 0.02
    1250 6.92 0.45 4.17 0.55 0.66 0.01 3.72 0.51 0.86 0.01 3.70 0.52 0.87 0.01
    1600 6.25 0.34 3.83 0.61 0.70 0.01 3.50 0.49 0.87 0.01 3.49 0.61 0.88 0.01
    2000 5.29 0.43 3.45 0.73 0.70 0.02 3.21 0.47 0.85 0.01 3.21 0.52 0.85 0.01
    2500 4.06 0.49 2.90 0.41 0.68 0.01 2.76 0.42 0.80 0.01 2.76 0.59 0.81 0.02
    3150 3.37 0.57 2.54 0.59 0.57 0.02 2.45 0.40 0.78 0.02 2.44 0.48 0.78 0.02
    4000 2.80 0.48 2.23 0.46 0.63 0.02 2.17 0.36 0.72 0.02 2.17 0.48 0.72 0.02
    5000 2.20 0.55 1.85 0.50 0.59 0.03 1.82 0.40 0.66 0.02 1.80 0.48 0.69 0.03
    6300 1.67 0.38 1.48 0.44 0.54 0.03 1.45 0.39 0.62 0.02 1.43 0.44 0.68 0.03
    8000 1.21 0.53 1.11 0.50 0.50 0.04 1.09 0.68 0.58 0.05 1.08 0.60 0.65 0.05
    10000 0.89 0.78 0.83 0.85 0.51 0.09 0.83 0.61 0.58 0.08 0.82 0.64 0.70 0.08
  • The values obtained for AAC and NRC are given in Table IV below.
    TABLE IV
    Test Nos. 12, 13, and 14, values obtained for
    NRC and AAC
    NRC AAC
    Test
    12 0.85 0.87
    Test 13 0.8 0.8
    Test 14 0.5 0.51
  • The acoustic absorption values obtained during tests 12, 13, and 14 are plotted on the graph of FIG. 7, with only frequencies lying in the range 125 Hz to 4000 Hz being taken into account so as to make them comparable with the presentation of the graphs of FIGS. 2 to 6.
  • Combining a microperforated membrane with fiber insulation placed at a distance from the rigid wall makes it possible to obtain acoustic attenuation that is uniform over the entire range of frequencies under consideration.
  • The tests performed for the first and second series mentioned above made use of an acoustic chamber having walls made of glass fiber, and that does not correspond to the real situation for tensioned ceilings.
  • In order to obtain a better evaluation of the impact of the presence of the support for the tensioned sheet on the acoustic attenuation properties of the entire assembly, a third series of tests was performed under the following conditions.
  • TEST A
  • 8′×9′ panels of glass fibers having a total weight of 0.25 pounds per square foot (psf), thickness of 1″ (density 3 lb/cu.ft) surrounded by a tubular metal frame having a height of 4″ and a nominal thickness of 1½″ were fixed directly on the base wall of the reverberation chamber (setup A in the standard ASTM E 795).
  • Those frames constituted supports for tips of smooth tensioned PVC material.
  • TEST B
  • 8′×9′ panels of smooth PVC (5 thousandths of an inch. (mil)) were placed using a barb/rail mount at 4″ from the end wall of the reverberation chamber (E90 setup of the standard ASTM E 795).
  • The frame supporting the smooth PVC panels was of metal tubes having a height of 4″ and a nominal thickness of 1½″.
  • The frame was fixed on the outside to the base wall of the reverberation chamber.
  • A 2″ thick glass fiber panel (density 3 lb/cu.ft) was placed directly on the end wall of the chamber.
  • The total weight of the glass fiber panel was 0.49 psf, with the PVC strip weighing 0.05 psf.
  • TEST C
  • 8′×9′ panels of smooth (5 mil) PVC were placed using a barb/rail mount at 4″ from the end wall of the reverberation chamber (E90 setup of the standard ASTM E 795).
  • The support frame for the smooth PVC panels was made of metal tubes having a height of 4″ and a nominal thickness of 1½″.
  • The frame was fixed on the outside to the base wall of the reverberation chamber.
  • A 1″ thick (density 3 lb/cu.ft) glass fiber panel was placed directly on the end wall of the chamber.
  • The total weight of the glass fiber panel was 0.25 psf, the PVC strip weighing 0.05 psf.
  • The results obtained are given in Table V below.
    TABLE V
    Results obtained for tests A, B, and C
    Acoustic Acoustic Acoustic
    absorption absorption absorption
    coefficient Sabins coefficient Sabins coefficient Sabins
    Test A Test A Test B Test B Test C Test C
    100 0.05 3.6 0.17 12.5 0.09 6.6
    125 0.07 5.3 0.28 20.0 0.14 9.8
    160 0.12 8.3 0.47 33.8 0.24 17.2
    200 0.21 15.3 0.75 54.3 0.34 24.7
    250 0.30 21.6 1.02 73.5 0.52 37.1
    315 0.45 32.6 1.11 80.0 0.70 50.3
    400 0.66 47.5 1.08 77.9 0.87 62.5
    500 0.69 49.6 0.84 60.7 0.69 50.0
    630 0.71 50.9 0.66 47.3 0.52 37.1
    800 0.72 52.0 0.52 37.3 0.39 27.9
    1000 0.74 53.3 0.42 29.9 0.30 21.3
    1250 0.78 56.4 0.34 24.8 0.25 18.2
    1600 0.83 60.1 0.30 21.3 0.28 19.9
    2000 0.87 62.6 0.25 18.2 0.31 22.4
    2500 0.92 65.9 0.22 15.7 0.25 17.9
    3150 0.94 67.7 0.18 13.2 0.21 14.8
    4000 0.98 70.2 0.15 11.0 0.18 13.3
    5000 1.01 72.5 0.13 9.3 0.18 13.0
  • The NRC and mean NRC values obtained for tests A, B, C are given in Table VI below.
    TABLE VI
    NRC values obtained for tests A, B, and C
    Test A Test B Test C
    NRC Moyen 0.65 0.633 0.455
    NRC 0.65 0.65 0.45
  • The values for the acoustic absorption coefficients were obtained using the terms of standard ASTM C 423-90a using a Bruel Kjaer type 2133 analyzer.
  • The histograms of FIGS. 8, 9, and 10 show how the acoustic absorption coefficients vary with frequency for frequencies lying in the range 100 Hz to 5000 Hz for tests A, B, and C.
  • The flexible sheet polymer material having improved acoustic properties as described above is suitable for use in tensioned decorative or masking structures, such as those constituting false ceilings or false walls, in particular.
  • The material can also be used for display panels, whether of the fixed type or of the moving type, with the attenuation in reverberation making it possible to reduce the sound nuisance that is generated by such panels.
  • Since the visual appearance of the material is not significantly altered by making the microprojections, the material remains entirely suited for use in industrial premises and in hospitals, and also for use in public buildings or in recent or historic dwellings.
  • The acoustic properties obtained using these materials are entirely comparable with those obtained using conventional suspended ceilings, as can be seen from the following table, given by way of indication.
    TABLE VII
    Comparison of the acoustic properties of
    a microperforated sheet of the invention with
    conventional ceiling plates
    125 250 500 1000 2000 4000
    Product Hz Hz Hz Hz Hz Hz AAC
    Suspended ceiling 0.23 0.32 0.40 0.87 0.74 0.83 0.55
    plate a (Armstrong)
    Suspended ceiling 0.34 0.32 0.40 0.64 0.71 0.76 0.55
    plate b (Armstrong)
    Suspended ceiling 0.33 0.31 0.53 0.68 0.62 0.52 0.55
    plate c (Armstrong)
    New Mat 0.27 0.35 0.45 0.58 0.70 0.63 0.50
    microperforated
    tensioned sheet
    (test 14)

Claims (29)

1. A flexible sheet material of thickness less than half a millimeter for making tensioned structures such as false ceilings, wherein the material includes microprojections formed by displacing the material from which it is made, said material presenting an acoustic absorption coefficient which is higher than that of the same material without said projections.
2. The material according to claim 1, wherein the height of the microprojections measured in a direction perpendicular to the plane of said sheet in the vicinity of said microprojections is less than three times the thickness of said sheet.
3. The material according to claim 1, wherein the microprojections project on one side only of said sheet.
4. The material according to claim 3, wherein each of the microprojections is located at a node of a regular pattern.
5. The material according to claim 4, characterized in that all of the microprojections are located at the nodes of a single pattern.
6. The material according to claim 5, wherein the pattern has a square mesh.
7. The material according to claim 1, wherein its microprojections project from both faces of said sheet.
8. The material according to claim 7, wherein each microprojection is located at a node of a regular pattern.
9. The material according to claim 8, wherein all of the microprojections are disposed at the nodes of a single pattern.
10. The material according to claim 9, wherein the pattern has a square mesh.
11. The material according to claim 1, wherein the microprojections are in the form of depressions having a substantially plane end wall connected to an opening via a strip of material of thickness that is smaller than or equal to the thickness of portions of the sheet between the microprojections.
12. The material according to claim 11, wherein the depressions are circularly symmetrical about respective axes that are substantially perpendicular to their end walls.
13. The material according to claim 12, wherein the strip of material connecting the end wall of a depression to its opening is discontinuous.
14. The material according to claim 1, wherein the material is provided with microperforations, having openings smaller than four-tenths of a millimeter.
15. The material according to claim 14, wherein at least a fraction of the microprojections are provided with said microperforations.
16. The material according to claim 14, wherein said microperforations are disposed between the microprojections.
17. The material according to claim 16, wherein the microperforations are disposed at the nodes of a pattern.
18. The material according to claim 17, wherein the microperforations are disposed at the nodes of a pattern identical to the pattern of the microprojections and offset relative thereto.
19. The material according to claim 14, wherein the density of microperforations lies in the range 2 to 60 per square centimeter.
20. The material according to claim 1, the material is selected from the group comprising plastified polyvinyl chlorides, vinylidene chlorides, copolymers of vinyl chloride and vinylidene chloride, and any other equivalent material.
21. The material according to claim 1, wherein the area occupied by the microprojections lies in the range 0.5% to 10% of the area of said sheet.
22. A method of making a sheet of material as presented in claim 1, comprising a step of needling, locally displacing the material constituting the sheet, in a predetermined pattern.
23. The method according to claim 22, wherein the needling step is performed without the sheet suffering any removal of material.
24. The method according to claim 22, wherein the needles used in the needling method have a tip diameter less than one-tenth of millimeter.
25. The method according to claim 22, wherein the needling step is performed while the sheet of material is placed under tension of the same order as the tension of the sheet in final use in a tensioned structure.
26. The material according to claim 2, wherein:
the microprojections project on one side only of said sheet;
each of the microprojections is located at a node of a regular pattern;
all of the microprojections are located at the nodes of a single pattern;
the pattern has a square mesh.
27. The material according to claim 2, wherein:
its microprojections project from both faces of said sheet;
each microprojection is located at a node of a regular pattern;
all of the microprojections are disposed at the nodes of a single pattern;
the pattern has a square mesh;
the microprojections are in the form of depressions having a substantially plane end wall connected to an opening via a strip of material of thickness that is smaller than or equal to the thickness of portions of the sheet between the microprojections;
the depressions are circularly symmetrical about respective axes that are substantially perpendicular to their end walls;
the strip of material connecting the end wall of a depression to its opening is discontinuous;
the material is provided with microperforations, having openings smaller than four-tenths of a millimeter;
at least a fraction of the microprojections are provided with said microperforations or said microperforations are disposed between the microprojections.
28. The material according to claim 16, wherein:
the microperforations are disposed at the nodes of a pattern;
the microperforations are disposed at the nodes of a pattern identical to the pattern of the microprojections and offset relative thereto;
the density of microperforations lies in the range 2 to 60 per square centimeter;
the material is selected from the group comprising plastified polyvinyl chlorides, vinylidene chlorides, copolymers of vinyl chloride and vinylidene chloride, and any other equivalent material;
the area occupied by the microprojections lies in the range 0.5% to 10% of the area of said sheet.
29. The method of making a sheet of material as presented in claim 1, wherein:
the method comprises a step of needling, locally displacing the material constituting the sheet, in a predetermined pattern;
the needling step is performed without the sheet suffering any removal of material;
the needles used in the needling method have a tip diameter less than one-tenth of a millimeter;
the needling step is performed while the sheet of material is placed under tension of the same order as the tension of the sheet in final use in a tensioned structure.
US11/099,142 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials Abandoned US20050186392A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US11/099,142 US20050186392A1 (en) 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US12/431,383 US8906486B2 (en) 2000-03-20 2009-04-28 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
PCT/FR2000/000682 WO2001071116A1 (en) 2000-03-20 2000-03-20 Flexible sheet fabrics for tensile structures, method for making same, tensile false ceilings comprising same
US09/979,245 US7059089B1 (en) 2000-03-20 2000-03-20 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US11/099,142 US20050186392A1 (en) 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Related Parent Applications (3)

Application Number Title Priority Date Filing Date
US09/979,245 Division US7059089B1 (en) 2000-03-20 2000-03-20 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US09979245 Division 2000-03-20
PCT/FR2000/000682 Division WO2001071116A1 (en) 2000-03-20 2000-03-20 Flexible sheet fabrics for tensile structures, method for making same, tensile false ceilings comprising same

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US12/431,383 Continuation US8906486B2 (en) 2000-03-20 2009-04-28 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Publications (1)

Publication Number Publication Date
US20050186392A1 true US20050186392A1 (en) 2005-08-25

Family

ID=8846089

Family Applications (4)

Application Number Title Priority Date Filing Date
US09/979,245 Expired - Lifetime US7059089B1 (en) 2000-03-20 2000-03-20 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US11/099,142 Abandoned US20050186392A1 (en) 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US11/099,357 Expired - Fee Related US7467498B2 (en) 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US12/431,383 Expired - Fee Related US8906486B2 (en) 2000-03-20 2009-04-28 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US09/979,245 Expired - Lifetime US7059089B1 (en) 2000-03-20 2000-03-20 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Family Applications After (2)

Application Number Title Priority Date Filing Date
US11/099,357 Expired - Fee Related US7467498B2 (en) 2000-03-20 2005-04-05 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US12/431,383 Expired - Fee Related US8906486B2 (en) 2000-03-20 2009-04-28 Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials

Country Status (10)

Country Link
US (4) US7059089B1 (en)
EP (1) EP1180186B2 (en)
AT (1) ATE288001T1 (en)
AU (1) AU3300900A (en)
CA (1) CA2374414C (en)
DE (1) DE60017725T3 (en)
DK (1) DK1180186T4 (en)
ES (1) ES2237411T5 (en)
PT (1) PT1180186E (en)
WO (1) WO2001071116A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007127891A2 (en) * 2006-04-27 2007-11-08 3M Innovative Properties Company Methods of making structured films
US20090000219A1 (en) * 2007-06-29 2009-01-01 Carlson Gregory L Acoustic reflective panel assembly
US20090233045A1 (en) * 2006-04-27 2009-09-17 Slama David F Structured films having acoustical absorbance properties
US20110048850A1 (en) * 2008-05-05 2011-03-03 Alexander Jonathan H Acoustic composite
US9194124B2 (en) 2011-12-09 2015-11-24 3M Innovative Properties Company Acoustic light panel
US20160185521A1 (en) * 2013-08-02 2016-06-30 Roquette Freres Flexible storage device comprising a flexible container and an inner liner

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7637698B2 (en) * 2004-10-22 2009-12-29 Meernik Paul R Tent ground cloth with drainage
JP5039559B2 (en) * 2004-11-26 2012-10-03 エージェンシー フォー サイエンス,テクノロジー アンド リサーチ Fine structure manufacturing method and fine structure manufacturing apparatus
FR2926099B1 (en) * 2008-01-09 2010-03-19 Normalu PATCH FOR ACCOUSTIC TIGHTS, SEALED AND PARTIALLY TRANSLUCENT
US20100014282A1 (en) * 2008-07-15 2010-01-21 Michael Danesh Fire-resistant and noise attenuating recessed lighting assembly
US8657067B1 (en) 2012-09-25 2014-02-25 The Boeing Company Acoustic damping device for noise reduction
EP2783656B1 (en) 2013-03-15 2017-06-28 American Orthodontics Corporation Self-ligating bracket
FR3101653B1 (en) 2019-10-02 2022-02-18 Newmat PROFILE ELEMENT FOR FALSE WALL WITH STRETCHED CANVAS, FALSE WALL COMPRISING SUCH PROFILE ELEMENT
FR3105552B1 (en) * 2019-12-23 2022-05-27 Saint Gobain Isover THERMAL AND ACOUSTIC INSULATION ASSEMBLY COMPRISING A THERMAL AND ACOUSTIC INSULATION PRODUCT AND A MEMBRANE ON THE FRONT FACE
FR3120884B1 (en) 2021-03-16 2023-04-14 Newmat Profile for maintaining a fabric for a false ceiling and false ceiling comprising such a profile

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1726500A (en) * 1928-12-28 1929-08-27 Burgess Lab Inc C F Sound-deadening construction
US1918149A (en) * 1931-05-08 1933-07-11 Burgess Lab Inc C F Sound transmitting and sound absorbing construction
US3782495A (en) * 1972-06-08 1974-01-01 M Nassof Ceiling tile
US4219376A (en) * 1979-03-05 1980-08-26 L. E. Carpenter & Company, Inc. Flexible acoustical wall covering, method of making same, and wall panel employing same
US4343848A (en) * 1980-12-15 1982-08-10 Ethyl Corporation Embossed thermoplastic material
US4835914A (en) * 1987-02-27 1989-06-06 Fernand Scherrer False ceiling constituted by a stretched sheet fixed along its edges to a support frame
US5491309A (en) * 1988-03-28 1996-02-13 Quilite International Limited Liability Company Acoustical panel system
US5740649A (en) * 1993-04-20 1998-04-21 Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. False ceiling
US6598701B1 (en) * 2000-06-30 2003-07-29 3M Innovative Properties Company Shaped microperforated polymeric film sound absorbers and methods of manufacturing the same
US6617002B2 (en) * 1998-07-24 2003-09-09 Minnesota Mining And Manufacturing Company Microperforated polymeric film for sound absorption and sound absorber using same
US6640507B1 (en) * 1999-09-23 2003-11-04 Saint-Gobain Isover Acoustic building structure
US6782971B2 (en) * 2002-02-19 2004-08-31 Ets-Lindgren, L.P. Serviceable acoustic interiors
US6977109B1 (en) * 1998-07-24 2005-12-20 3M Innovative Properties Company Microperforated polymeric film for sound absorption and sound absorber using same
US7111434B2 (en) * 2000-11-06 2006-09-26 Clipso Swiss Ag Method for producing a panel substantially stretched on a frame and resulting panel

Family Cites Families (93)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3126978A (en) * 1964-03-31 Acoustical and thermal insulation
US1554179A (en) * 1922-09-05 1925-09-15 Dahlberg & Company Sound-absorbing material for walls and ceilings
US2990027A (en) * 1957-07-11 1961-06-27 Celotex Corp Composite sound absorber
US3087577A (en) * 1960-01-18 1963-04-30 Michael J Prestia Ceiling tile with sound attenuating and visual effects
GB914430A (en) 1960-04-12 1963-01-02 Nils Emil Lennart Bergstroem Method for mounting of plastic sheet material, particularly as ceiling covering in a room, and tool for accomplishing the method
FR1303930A (en) 1961-10-18 1962-09-14 Barracudaverken Ab Device for fixing a thin sheet of elastic material between opposing walls of a room in a building
SE309667B (en) 1965-04-12 1969-03-31 Barracuda Center Ab
SE323189B (en) 1968-02-20 1970-04-27 Barracudaverken Ab
US3649430A (en) * 1965-10-21 1972-03-14 American Cyanamid Co Vibration damping laminates
FR1515260A (en) 1967-01-13 1968-03-01 New method of fixing plastic covering for walls and ceilings
SE331184B (en) 1970-02-13 1970-12-14 O Blick
AR199871A1 (en) 1970-05-08 1974-10-08 Ici Ltd A METHOD TO PERFOR A THERMOPLASTIC MATERIAL FILM AND A DEVICE TO CARRY OUT SUCH METHOD
GB1360975A (en) 1970-09-09 1974-07-24 Ici Ltd Suspended ceiling
US3712846A (en) * 1971-06-23 1973-01-23 Carpenter L & Co Acoustical panel
FR2145147A5 (en) 1971-07-06 1973-02-16 Ms Handel Manfred Schier
BE780464A (en) 1972-03-10 1972-07-03 Tombu Gerard IMPROVEMENTS TO THE HANGING PROFILES FOR FIXING TO WALL TABLES.
FR2202997B2 (en) 1972-08-13 1979-04-13 Ici Ltd
FR2270407A1 (en) 1974-03-01 1975-12-05 Moreton Pierre Covering layer with concealed attachment - has layer doubled around angle member fitting behind block secured to surface
US3948347A (en) 1974-11-25 1976-04-06 Gallagher-Kaiser Corporation Acoustical panel
US3965906A (en) * 1975-02-24 1976-06-29 Colgate-Palmolive Company Absorbent article with pattern and method
FR2310450A1 (en) 1975-05-07 1976-12-03 Anthonioz Camille IMPROVEMENTS TO FALSE CEILINGS AND FALSE WALLS
US4055180A (en) * 1976-04-23 1977-10-25 Colgate-Palmolive Company Absorbent article with retained hydrocolloid material
DE2753467A1 (en) 1977-02-18 1978-08-24 Armstrong Cork Co HANGING CEILING SYSTEM
LU77230A1 (en) 1977-04-29 1978-06-01
FR2405818A1 (en) 1977-10-14 1979-05-11 Sable Freres Int PVC coated polyurethane foam backed fabric for acoustic insulation - esp. for lining lorry or tractor cabs etc.
JPS6029349B2 (en) * 1978-10-06 1985-07-10 大日本印刷株式会社 Decorative material manufacturing method
US4213516A (en) 1978-11-29 1980-07-22 American Seating Company Acoustical wall panel
DK4379A (en) 1979-01-04 1980-07-05 Daempa As SOUND ABSORPTION UNIT
DE2930123A1 (en) 1979-07-25 1981-02-12 Wilhelmi Holzwerk SOUND-absorbing building board
US4248647A (en) 1979-08-07 1981-02-03 Armstrong Cork Company Method for producing acoustical ceiling tile faced with a smooth distortion free decorative thin plastic film
FR2475093A1 (en) 1980-02-05 1981-08-07 Scherrer Fernand PROFILE CONSISTING OF AN EXTERIOR WALL OF A FALSE CEILING OR A WALL WALL
FR2486127A1 (en) 1980-07-07 1982-01-08 Allemann Roland TENSIONED CEILING
US4441580A (en) 1980-10-17 1984-04-10 Steelcase Inc. Acoustical control media
FR2523622A1 (en) 1982-03-18 1983-09-23 Perradin Guy PROCESS FOR PRODUCING FALSE CEILINGS AND FALSE CEILINGS OBTAINED
AU557379B2 (en) 1982-03-22 1986-12-18 Armstrong World Industries, Inc. Acoustical ceiling board
FR2524922A1 (en) 1982-04-13 1983-10-14 Scherrer Fernand Horizontally stretched sheet mounting for false ceilings - has sheet edge hook gripping edge beam shoulder
FR2544358B1 (en) 1982-06-02 1986-04-11 Uzan Daniel PASSIVE ACOUSTIC ABSORBER DEVICE FOR AIR PASSAGE, ALSO ABSORBING LOW FREQUENCIES
FR2531012B1 (en) 1982-07-30 1985-11-08 Gaillard Patrick PROFILE FOR LAYING FABRICS IN WALL COVERING
DE3242940A1 (en) 1982-11-20 1984-05-24 Hans Julius 6303 Hungen Schmitt ACOUSTICALLY EFFECTIVE COMPONENT
FR2537112A1 (en) 1982-12-02 1984-06-08 Bernardy Claude Device for positioning and fixing flexible sheets
IT1169744B (en) 1983-07-12 1987-06-03 Laterlite Spa COLD BITUMINOUS CONGLOMERATE ESPECIALLY FOR ROAD MAINTENANCE AND PROCEDURE FOR ITS PRODUCTION
FR2552473B1 (en) 1983-09-27 1986-10-17 Chiausa Christian METHOD OF PERFORMING FALSE CEILINGS, AND FALSE CEILINGS OBTAINED BY THE IMPLEMENTATION OF THIS PROCESS
FR2573798B2 (en) 1984-11-27 1987-12-24 Thierry Martin IMPROVEMENTS ON WOODEN SLABS WITH INTEGRATED SOUND AND THERMAL INSULATION FOR COVERING FLOORS, WALLS AND THE LIKE
FR2561690B1 (en) 1984-03-21 1987-07-10 Chenel Guy FALSE CEILING ELEMENT
FR2587447B1 (en) 1985-09-13 1988-09-16 Scherrer Fernand SPOT CHAIR FOR A FALSE CEILING OR FALSE WALL
FR2587392B1 (en) 1985-09-13 1991-06-21 Scherrer Fernand FALSE CEILING OR FALSE WALL CONSISTING OF A TENSIONED TABLECLOTH
FR2592416B1 (en) 1985-12-26 1989-06-02 Fibraconsult Management Beratu INSULATING PANEL FOR CEILING, AND METHOD FOR MANUFACTURING THE SAME
FR2597906A1 (en) 1986-04-25 1987-10-30 Bouttier Dominique Fastening device for a stretched flexible false ceiling
DE3643481A1 (en) 1986-05-14 1987-11-19 Pape Hans SOUND ABSORPTION COATING OF AN ACOUSTIC WALL OR ACOUSTIC CEILING
FR2611776A1 (en) 1987-02-24 1988-09-09 Brunel Christian Method and panel for sound absorption
SE461048B (en) 1987-03-02 1989-12-18 Gyproc Ab PERFORED, SOUND-ABSORBING DISC
FR2619531A1 (en) 1987-08-18 1989-02-24 Nicot Jean Pierre Device for attaching ceilings or stretched fabrics of all types
FR2623540A1 (en) 1987-11-23 1989-05-26 Dur Lumen Stretched fabric false ceiling
FR2624167A1 (en) 1987-12-07 1989-06-09 Ruhlmann Rene Level-compensation section for ceiling or wall coverings, in particular for stretched ceilings
FR2627207A1 (en) 1988-02-12 1989-08-18 Bidini Jean Claude Tensioned fabric ceiling assembly system - uses concealed edging strips and arrow-head anchor elements inserted with special tool
FR2630476B1 (en) 1988-04-22 1990-08-24 Scherrer Fernand FALSE-CEILING CONSISTING OF A TENSIONED CLOTH HANGED ALONG ITS EDGES, TO A SUPPORT FIXED TO THE WALLS OF A PIECE OF A BUILDING
FR2645135B1 (en) 1989-03-31 1991-08-16 Philippe Jean Pierre METHOD AND INSTALLATION FOR UNLOCKING AN ELEVATOR OR LIFT CAR ACCIDENTALLY IMMOBILIZED BETWEEN TWO LANDINGS
FR2648496B1 (en) * 1989-05-25 1994-04-15 Bader Michel FALSE CEILINGS IN FABRICS TIGHTENED AT LEAST IN PART PERMEABLE USED TO CREATE A VOLUME OF AIR DISTRIBUTION IN HEATING OR AIR CONDITIONING
FR2658849B1 (en) 1990-02-23 1997-04-04 New Mat Sa DEVICE FOR ATTACHING AND HOLDING IN TENSION OF AT LEAST ONE FLEXIBLE SHEET, SHEETS OF FLEXIBLE MATERIAL EQUIPPED WITH AT LEAST ONE MEMBER ACCORDING TO THIS DEVICE AND INSTALLATIONS USING AT LEAST ONE SHEET.
US5058340A (en) 1990-03-16 1991-10-22 Muller Jurgen H Custom stretched ceilings
US5091235A (en) * 1990-05-04 1992-02-25 E. I. Du Pont De Nemours And Company Laminated sill wrap assembly for providing an air infiltration barrier
US5085340A (en) 1990-12-28 1992-02-04 Rubbermaid Incorporated System for locking a waste receptacle
US5501047A (en) 1991-04-15 1996-03-26 Profilfix Securement profile for wall covering with invisible mounting
CH683855A5 (en) 1991-07-24 1994-05-31 Zdzislaw Pregowski Sound absorbing plate.
US5169712A (en) * 1991-08-23 1992-12-08 Amoco Corporation Porous film composites
FR2685036B1 (en) 1991-12-13 1995-03-17 Ruhlmann Rene INVISIBLE JOINING DEVICE, PARTICULARLY FOR TIGHT CANVAS.
CH683496A5 (en) 1992-02-04 1994-03-31 Magnetic Elektromotoren Ag Drive for displacement of movable part of mechanism
FR2691193B1 (en) 1992-05-13 1994-08-05 Hosteing Guy PROFILES TO SUPPORT AND TENSION A FALSE CEILING OR A FALSE WALL.
FR2692302B1 (en) 1992-06-16 1994-09-09 Newmat Sa Method for tensioning and mounting a flexible and elastic sheet and means for implementing this method.
FR2695670B1 (en) 1992-09-14 1994-11-25 Newmat Hanging device for a flexible and elastic sheet stretched between two supports to constitute in particular a false ceiling and false ceiling provided with such a hanging device.
FR2698647B1 (en) 1992-12-01 1995-02-03 Andre Bellamy Device for keeping a panel of flexible material stretched by its edges.
FR2699613B1 (en) 1992-12-08 1995-03-31 Newmat Sa Temporary holding accessory at a short distance from a flexible sheet to be stretched between two supports.
FR2699211A1 (en) 1992-12-11 1994-06-17 Swal Sarl Extruded strip for fixing coverings to surfaces - includes L=shaped body with shorter leg parallel to surface to be covered and bent back double to form jaws with longer leg extension, this longer leg having provision for permitting fixing of strip to surface
FR2699209A1 (en) 1992-12-11 1994-06-17 Swal Sarl Profile strip for holding wall cladding
DE9300152U1 (en) 1993-01-08 1993-03-11 Wilhelmi Werke Gmbh & Co Kg, 6335 Lahnau, De
FR2703711A1 (en) 1993-04-08 1994-10-14 Hosteing Guy Improvements made to the implementation of a false ceiling or a false wall
WO1994024382A1 (en) 1993-04-20 1994-10-27 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. False ceiling
DE4315499C2 (en) 1993-05-10 1997-02-06 Kluth Marlene Profile strip for fastening tensioning tracks and for hanging objects
FR2707708B1 (en) 1993-07-12 1996-01-05 Rene Philippe Ruhlmann Removable device for blocking the hanging of stretched fabrics.
FR2712006B1 (en) 1993-11-05 1997-01-24 Marc Gagliardi New device for laying wall coverings and means for this realization.
FI945224A (en) 1993-11-08 1995-05-09 Saint Gobain Isover Absorbent acoustic disc
FR2712325B1 (en) 1993-11-09 1996-02-23 Newmat Sa Method of manufacturing tiles, especially for suspended ceilings.
FR2727711B1 (en) 1994-12-05 1997-01-24 Newmat Sa TENSION SHEET SHEET FOR CONSTRUCTION OF SUSPENDED CEILINGS AND SUSPENDED CEILING PROVIDED WITH SAME
FR2732381A1 (en) 1995-03-29 1996-10-04 Biguet Guy Airborne sound reducing panel
FR2734296B1 (en) 1995-05-17 1997-08-08 Ringaud Jean FIXING PROFILE FOR TENSILE CEILING WITH INVISIBLE FINISH
US5888614A (en) * 1995-06-06 1999-03-30 Donald H. Slocum Microperforated strength film for use as an anti-infiltration barrier
FR2736615B1 (en) 1995-07-13 1997-09-19 Aerospatiale SLOTTED NUT DEVICE FOR MICROSATELLITE, WITH MECHANICAL AND PYROTECHNIC REDUNDANCY
DE19626676A1 (en) * 1996-07-03 1998-01-08 Kaefer Isoliertechnik Device for reducing sound levels in buildings
FR2751682B1 (en) 1996-07-26 1998-09-25 Fernand Scherrer WALL FABRIC TILE
FR2756600B1 (en) 1996-12-04 1999-03-19 Newmat Sa DEVICE FOR FIXING A SHEET TENSIONED BETWEEN TWO OPPOSITE WALLS
FR2767851B3 (en) 1997-08-26 1999-10-29 Guy Luc Piat FALSE TENSE CEILING
DE19754107C1 (en) * 1997-12-05 1999-02-25 Fraunhofer Ges Forschung Sound absorber, for suspension from ceiling
EP1020846B1 (en) * 1999-01-14 2018-09-19 Nichias Corporation Sound absorbing structure

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1726500A (en) * 1928-12-28 1929-08-27 Burgess Lab Inc C F Sound-deadening construction
US1918149A (en) * 1931-05-08 1933-07-11 Burgess Lab Inc C F Sound transmitting and sound absorbing construction
US3782495A (en) * 1972-06-08 1974-01-01 M Nassof Ceiling tile
US4219376A (en) * 1979-03-05 1980-08-26 L. E. Carpenter & Company, Inc. Flexible acoustical wall covering, method of making same, and wall panel employing same
US4343848A (en) * 1980-12-15 1982-08-10 Ethyl Corporation Embossed thermoplastic material
US4835914A (en) * 1987-02-27 1989-06-06 Fernand Scherrer False ceiling constituted by a stretched sheet fixed along its edges to a support frame
US5491309A (en) * 1988-03-28 1996-02-13 Quilite International Limited Liability Company Acoustical panel system
US5641950A (en) * 1988-03-28 1997-06-24 Quilite International Limited Liability Company Acoustical panel system
US5740649A (en) * 1993-04-20 1998-04-21 Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. False ceiling
US6617002B2 (en) * 1998-07-24 2003-09-09 Minnesota Mining And Manufacturing Company Microperforated polymeric film for sound absorption and sound absorber using same
US6977109B1 (en) * 1998-07-24 2005-12-20 3M Innovative Properties Company Microperforated polymeric film for sound absorption and sound absorber using same
US6640507B1 (en) * 1999-09-23 2003-11-04 Saint-Gobain Isover Acoustic building structure
US6598701B1 (en) * 2000-06-30 2003-07-29 3M Innovative Properties Company Shaped microperforated polymeric film sound absorbers and methods of manufacturing the same
US7111434B2 (en) * 2000-11-06 2006-09-26 Clipso Swiss Ag Method for producing a panel substantially stretched on a frame and resulting panel
US6782971B2 (en) * 2002-02-19 2004-08-31 Ets-Lindgren, L.P. Serviceable acoustic interiors

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101432116B (en) * 2006-04-27 2012-10-10 3M创新有限公司 Methods of making structured films
WO2007127891A3 (en) * 2006-04-27 2007-12-21 3M Innovative Properties Co Methods of making structured films
US20090233045A1 (en) * 2006-04-27 2009-09-17 Slama David F Structured films having acoustical absorbance properties
WO2007127891A2 (en) * 2006-04-27 2007-11-08 3M Innovative Properties Company Methods of making structured films
US8367184B2 (en) * 2006-04-27 2013-02-05 3M Innovative Properties Company Structured films having acoustical absorbance properties
KR101308300B1 (en) 2006-04-27 2013-09-17 쓰리엠 이노베이티브 프로퍼티즈 컴파니 Methods of making structured films
US20090000219A1 (en) * 2007-06-29 2009-01-01 Carlson Gregory L Acoustic reflective panel assembly
US7918312B2 (en) * 2007-06-29 2011-04-05 Carlson Gregory L Acoustic reflective panel assembly
US20110048850A1 (en) * 2008-05-05 2011-03-03 Alexander Jonathan H Acoustic composite
US8381872B2 (en) 2008-05-05 2013-02-26 3M Innovative Properties Company Acoustic composite
US9194124B2 (en) 2011-12-09 2015-11-24 3M Innovative Properties Company Acoustic light panel
US20160185521A1 (en) * 2013-08-02 2016-06-30 Roquette Freres Flexible storage device comprising a flexible container and an inner liner
US9938076B2 (en) * 2013-08-02 2018-04-10 Roquette Freres Flexible storage device comprising a flexible container and an inner liner

Also Published As

Publication number Publication date
US20090297767A1 (en) 2009-12-03
ES2237411T5 (en) 2009-06-03
ES2237411T3 (en) 2005-08-01
US8906486B2 (en) 2014-12-09
WO2001071116A1 (en) 2001-09-27
DK1180186T3 (en) 2005-06-06
DE60017725T3 (en) 2009-08-13
US7059089B1 (en) 2006-06-13
ATE288001T1 (en) 2005-02-15
US7467498B2 (en) 2008-12-23
CA2374414A1 (en) 2001-09-27
DE60017725T2 (en) 2006-01-12
CA2374414C (en) 2008-05-20
PT1180186E (en) 2005-05-31
EP1180186B1 (en) 2005-01-26
US20050188633A1 (en) 2005-09-01
DE60017725D1 (en) 2005-03-03
EP1180186B2 (en) 2009-01-14
AU3300900A (en) 2001-10-03
DK1180186T4 (en) 2009-05-11
EP1180186A1 (en) 2002-02-20

Similar Documents

Publication Publication Date Title
US7467498B2 (en) Flexible sheet materials for tensioned structures, a method of making such materials, and tensioned false ceilings comprising such materials
US7677359B2 (en) Sound absorbent
US4607466A (en) Method and apparatus for controlling reverberation of sound in enclosed environments
US5975238A (en) Plate resonator
RU2495500C2 (en) Sound-absorbing structure
US7178630B1 (en) Acoustic device for wall mounting for diffusion and absorption of sound
US6615951B1 (en) Absorbent material, consisting of a porous substance with double porosity
JP2018537604A (en) Soundproof drywall panel
EP3024993A1 (en) Acoustic panel
Gupta An analysis of acoustic treatment on recording studio
RU2238378C2 (en) Flexible sheet material for stretched structure, method of its production and sheet material for stretched suspended ceiling
EP0892386A2 (en) A resonance-absorption acoustic-insulation panel
Hawkins Studies and research regarding sound reduction materials with the purpose of reducing sound pollution
JP2001081878A (en) Sound absorbing panel and acoustic panel
KR102023366B1 (en) Sound absorbing sandwich panel
Szymanski Acoustical treatment for indoor areas
US4614553A (en) Method of manufacturing acoustic panels for controlling reverberation of sound in enclosed environments
Fuchs et al. Sound absorbers
Khan et al. Noise Control in Buildings
Vania et al. The Composition of Room with Acoustical Applications in the Ensemble Room of Purwacaraka College of Music
Remes Sound insulation of wooden double-leaf partitions
Gade 4 Sound absorbers and their application in room design
JP2022129181A (en) sound absorbing structure
Foreman et al. Absorption, Silencers, Room Acoustics, and Transmission Loss
Heng Acoustic absorption properties of materials

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION