CA2337834C - Multilayer film with polyolefin and polyvinyl chloride - Google Patents
Multilayer film with polyolefin and polyvinyl chloride Download PDFInfo
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- CA2337834C CA2337834C CA002337834A CA2337834A CA2337834C CA 2337834 C CA2337834 C CA 2337834C CA 002337834 A CA002337834 A CA 002337834A CA 2337834 A CA2337834 A CA 2337834A CA 2337834 C CA2337834 C CA 2337834C
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2250/00—Layers arrangement
- B32B2250/24—All layers being polymeric
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/30—Properties of the layers or laminate having particular thermal properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2327/00—Polyvinylhalogenides
- B32B2327/06—PVC, i.e. polyvinylchloride
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2331/00—Polyvinylesters
- B32B2331/04—Polymers of vinyl acetate, e.g. PVA
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2553/00—Packaging equipment or accessories not otherwise provided for
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/91—Product with molecular orientation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/13—Hollow or container type article [e.g., tube, vase, etc.]
- Y10T428/1328—Shrinkable or shrunk [e.g., due to heat, solvent, volatile agent, restraint removal, etc.]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/13—Hollow or container type article [e.g., tube, vase, etc.]
- Y10T428/1352—Polymer or resin containing [i.e., natural or synthetic]
- Y10T428/1379—Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31909—Next to second addition polymer from unsaturated monomers
- Y10T428/31913—Monoolefin polymer
- Y10T428/3192—Next to vinyl or vinylidene chloride polymer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31909—Next to second addition polymer from unsaturated monomers
- Y10T428/31928—Ester, halide or nitrile of addition polymer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31935—Ester, halide or nitrile of addition polymer
Abstract
A film includes a first layer including polyvinyl chloride; and a second lay er including a material such as anhydride functionalized polyolefin, ethylenelvinyl acetate copolymer having a vinyl acetate content of between 10 % and 35 %, ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10 % and 30 %, ethylenelalkyl methacrylate copolymer having an alkyl methacrylate content of between 10 % and 30 %, ethylene/acrylic acid copolymer having an acrylic aci d content of between 10 % and 30 %, ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10 % and 30 %, a nd ionomer. A layer of polyolefin, and/or an additional layer including any of the materials of the second layer, or polyvinyl chloride, can be optionally included in a film of the invention.
Description
MULTILAYER FILM WITH POLYOLEFIN AND POLYVINYL CHLORIDE
FIELD OF THE INVENTION
The present invention relates to a thermoplastic film containing polyolefin and polyvinyl chloride, which film can be utilized to package a wide variety of items.
BACKGROUND OF THE INVENTION
The present invention is directed to a new and useful film. Films, and especially heat shrinkable films are well known for many packaging applications.
Examples of such films are the polyolefinic films supplied commercially by Cryovac, Inc. These films have proven to be very useful in packaging applications where high shrink, good optics, impact resistance, tear initiation and tear propagation resistance are needed. Films of this type are disclosed in U.S. Patent Nos. 4,551,380 and 4,643,943, both to Schoenberg.
Polyvinyl chloride (hereinafter "PVC") films are also widely used in packaging applications.
PVC films exhibit good elastic recovery, high modulus, and low shrink tension, but poor sealability, and poor tear resistance. They also carbonize during a trim sealing processs.
It would be desirable to provide a film having the good sealability and tear resistance properties of polyolefinic films, but with the good elastic recovery, high modulus, and low shrink tension of PVC films.
la SUMMARY OF THE INVENTION
In a first aspect, a multilayer film comprises a first layer, having two major surfaces, comprising polyvinyl chloride; and a second layer, adhered to a first major surface of the first layer, comprising a material selected from the group consisting of anhydride functionalized polyolefin, ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10%
and 30% by weight of the ethylene/alkyl methacrylate copolymer, ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by .weight of the ethylene/methacrylic acid copolymer, and ionomer. Optionally, the film further comprises a third layer-, adhered to a second major surface of the first layer, comprising any of the materials of the second layer.
In a second aspect, a multilayer film comprises a core layer, having two major surfaces, comprising a material selected from the grou~.~ consisting of anhydric;~e functionalizec~ poayole:_ir~, ethylene/vinyl acetate copolymer having a viny:L acetate content of between 10% and 35% by weight of the ethylene/'vi.nyl acetate copolymer, ethylene/alkyt acrylat~e copolymer having an alkyl acryla.te content of between 10% a.nd 30'% by ~Neight of tine ethylene/alky:L ac:rylat7 o:opol.ymer, etriylene/a:Lkyl methacrylate copolymer lu:aving an al.ky7_ methac~-ylate content of between 10s and 30% b~.r weight of t:he ethylene/alkyl methacrylate Copolymer, ethylene/acryl,~c: acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/crcrylic acid copolymer, ethylene/meth.acrylic a~~.~d copolymer_ having a methacrylic acid content of between 10% and 30% by weight of the ethylene/meth~~crylic a:~:id copolymer, ancx ionomer; a first outer layer, adhered t:;:~ a f:i:rst major surface of the core layer, comprz.;~ing polyrir~y:l chiari.de; and a second outer layer, adhered to a second major ~~urfa~e of the core layer, 2 ~~ comprising po:Lyolef in or polyvinyl. chloride . The first outer layer c:ompzisinc~ polyvinyl chloride can optionally have adhered vo it, a fourth layer comprising any of the materials disclosed f<.~r the core layer.
In a third aaspect, a multilayer film comprises a core layer, 'maving two cnajor surfaces, comprising polyvinyl chloride; two interme~_~iate layers, each adhered to a respective major surface of the core layer, comprising a material selected fro~i take group consisting of anhydride 2a functionalized polyolefin, ethylene/vinyl acetate copolymer having a viny:l_ acetate cement of between to o and 35°s by weight of the ethylene!vinyl acetate copolymer, ethylene/alkyl acrylate~ copolymer caving an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylatf~: copolymer, ethylene/al.kyl methacrylate ~~opolymer having an alkyl methacrylate content of between 10'o and 30% by weight of the ethylE:ne/alkyl methacrylate copolymer, E:thylene/a~~ryl.ic acid copolymer having an acrylic acid content of between loo and 30% by weight of the ethylene/a.cryli.c acid copolymer, ethylene/methacrylic ac:i.d copolymer having a methacrylic acid content of between 10~s and 30o by weight of the ethylene/methacry:Lic ac:i.d copolymer., and ionocner; and two outer layers, each adhe~:c-ed to a major :surface of a respective intermediatE_~ Layer, compris~_ng polyolefin.
In one speci:Ei.c~ aspect, the ~.nvention provides a heat shrinkable multil.ayer film r:ompr:ising (a) a first layer, having two majox: surfaces, comer=:.sing polyvinyl chloride, and (b) a second layer, adhered in a first major surfaces of the first Layer, comprising a material selected from the group consisting of: (ii anhydride functionalized polyolefin, (ii) ethyl~an~~/~w~inyl acetate copolymer having a vinyl acetate content c:>:E bet.ween 10% and 35~ by weight of 2~; the ethylene%~rinyl acetate copolymer, (_~ii) ethylene/allcyl acrylate copo:Lymer having an alkyl acrylate content of between 10o aIld 3O-°s bj~ weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 1.0'o and 30% by weight of the: ethylene/alkyl methacrylate copolymer, (v) ethylene/acrvlic acid copolymer having an acrylic acid content of between 10~ and 30°s by weight of the ethylene/acrylic acid copolymer, ;vi) ethylene/methacrylic 2b acid copolyme~:~ having ~i methacrylic: acid content of between 10% and 30% bar weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, wherein the film has a shrink tension of bet~Neen 100 and 300 psi in at least one of the machine and transverse directions at 200'F, and a free shrink of between 25'% and 65% in at least. one of the machine and transverse di-~~,~scti.ons <~t 220°F.
In <:r furvther specific aspect, the :invention provides a he<:~t shrink<a.bl.e mul.tilayer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group consisting of (i) anhydride functionalized polyole:E:iri, (ii) et~:ylene/vinyl acetate copolymer having a vin,r~l. acetate contera of between 10% and 35% by weight of the e::h.ylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alky:i acrylat:e c:~opol.ymer, (i.v) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer,. ;v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene; ac.~.ryl_ic acid copolymer, (vi) ethylene/metha.cry:lic acid copolymer having a methacryl.ic:
acid content c>f between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer; (b) a first outer layer, ac~ihered to a first major surface of. the first layer, comprising ~?o:iyvinyl chloride; and (c) a second outer layer, adhered to ;~ second major surface of the first layer, compri:~ing polyolefin or polyvinvl_ chloride; wherein 3C the film has a shrink t=ens:ion of between 100 and 300 psi_ in at least one of the mo.clnine <~nd transverse directions at 200°F, and a free shrin k: of between 2.5 ~ and 65 % in at least one of the machine and transverse dire~~tions at 220°F.
2c In a still fl.irther specific aspect, the invention provides a hear shrinkable muli=ilayer film comprising: (a) a core layer, ha,Jing two major surfaces, comprising polyvinyl chloride; (b) two intermediate layers, each adhered to a respective major surfac~~e of the core layer, comprising a material selected from the group consisting of (e) anhydride functionalized polyole_~ir~, (ii) ethylene/vinyl acetate copolymer having a viyY~l acetate conter_t of between 10% and 35% by weight of the e~hylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an a~~_kyl acryla.te content of between 10% a.nd 30'% by weight of the ethylene/alky:L acx.-ylat ' c:opolymex-, ( iv) ethylene/alkyl.
methacrylate ~_opo.l.ymer leaving an a:Lkyl methacrylate content of between 10% and 300 1>y weight of thE: ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid <content. of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/meth<~crylic acid copolymer, and (vii) ionomer; and (c) two outer: layers, each adhered to a major surface of a respective iritermediat.e layer, comprising a poiyolef i:n;
wherein the f: elm has ~~ shrink ten.~ion of between 100 and 300 psi in at least cme o1= the machine and transverse directions at 200°F, and a free ~~l~:rink of between 25% and 55 % in air least one of the machinee arid tran:werse :lirec:tions at 220°F.
In a yet further specific aspect, the invention provides a heat shrine>abl.e multilayer film comprising (a) a first layer, having t~ao major surfaces, comprising polyvinyl chloride; and. (b) a second layer, adhered to a first major surface of tl-..e first _l.~irer. , comprising a material se7.ec:ted from the group consist~i..ng of_ : (:e) a.nhydride functionalized polyolefin, (ii) ethyLelne/vinyl acetate copolymer having a 2d vinyl acetate content c~f between 10% and 35% by weight of the ethylene/viny~. acetate copolymer, (iii) et.hylene/alkyl acrylate copolymer hav:i.ng an alkyl acrylate content of between 10 % a~:ld 30% by wE:ight of the ethylene/alkyl acrylate copolymer, (i~r) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate _:c~mt.ent of between 10% and 30% by weight of the ethylene/sl.kyl. methacrylate copolymer, (v) ethylene/acrylic acid ~~opolymer having an acrylic acid content of beLweer~ 10 % a.rud 3C% by sNeight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having _~ naethacrylic acid contf~nt of between 10% and 30% by weight ~of the ethylene rtiethacrylic acid copolymer, and (vii) ionomer; wherein the film has an oxygen transmission :rate of at :l..east 100 cc/square meter-day-atmosphere in accordance' with ASTM D 3985; and wherein the film has a shrink tens:LC7r1 Uf between 100 and 300 psi in at least one of the machine' and transverse directions at 200°F, and a free shrink of bet;vveen 25 % and ~:5°-<, in at least one of the machine and transverse directions at 220°F.
In ~.nother specific aspect, the invention provides a heat shrink~~ble mutt:..:Layer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group <:or=listing of : i; anhydride functionalized polyaletun, (ii) ethylene/vinyl acetate copolymer having a viny_L acetate content of between 10% and % by weight of the e~tny:Lene/vinyl acet::ate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10 0 and 30% by weight.. of the ethylene/alkyl acrylate wopolymer, (iv) ethylene/alkyl 3C~ methacrylate copolymer l:laving an a.:Lky-'~ rnethaCrylate content of between 10'-; and 30° by weight. o:E the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acx°~Tlic acid content: of between 10% and 30 % by 2e weight of the ethylene!acrylic acid copolymer, (vi) ethylene/methacrylic ac-_~.id copolymer having a methacrylic acid content of betweerL 1.0% and 30% by weight of the ethylene/meth<~cryiic awicL copolymer:, and (vii) ionomer, (b) a first outer layer, a~=~h.ered .in a first major surface of the first layer, comprisin~_~ polyvinyl chloride; and (c) a second outer layer, :adhered t~=,~ a second major surface. of the first layer, comprising poly~:~l.efin or polyvinyl chloride; wherein the film has an oxygen t.x~ansmissio:ru rate of at, least 100 cc/square meter-day--atmosphere in accordance with ASTM D 3985; ~~nd where:i.n the film fuas a shrink tension of between 100 ar:.d 300 ps:L ~n at least one of the machine and transverse directions <:~t: 200°F, and a free shz~ink of between 25% and 55% i:n at least.. rime of tine mac~hir~e and transverse directions at 220'~'F.
DEFINITIONS
"Anhydride functionalized po:Lyolefin" (ahPO) herein refers to any 1 o:rm of anhydride functionality, such as the anhydride of malei~~ acid, itacon_ic acid, etc., grafted onto a polyole.fin or copolymerized with a polyolefin; and optionally blended with one or more polyolefins.
FIELD OF THE INVENTION
The present invention relates to a thermoplastic film containing polyolefin and polyvinyl chloride, which film can be utilized to package a wide variety of items.
BACKGROUND OF THE INVENTION
The present invention is directed to a new and useful film. Films, and especially heat shrinkable films are well known for many packaging applications.
Examples of such films are the polyolefinic films supplied commercially by Cryovac, Inc. These films have proven to be very useful in packaging applications where high shrink, good optics, impact resistance, tear initiation and tear propagation resistance are needed. Films of this type are disclosed in U.S. Patent Nos. 4,551,380 and 4,643,943, both to Schoenberg.
Polyvinyl chloride (hereinafter "PVC") films are also widely used in packaging applications.
PVC films exhibit good elastic recovery, high modulus, and low shrink tension, but poor sealability, and poor tear resistance. They also carbonize during a trim sealing processs.
It would be desirable to provide a film having the good sealability and tear resistance properties of polyolefinic films, but with the good elastic recovery, high modulus, and low shrink tension of PVC films.
la SUMMARY OF THE INVENTION
In a first aspect, a multilayer film comprises a first layer, having two major surfaces, comprising polyvinyl chloride; and a second layer, adhered to a first major surface of the first layer, comprising a material selected from the group consisting of anhydride functionalized polyolefin, ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10%
and 30% by weight of the ethylene/alkyl methacrylate copolymer, ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by .weight of the ethylene/methacrylic acid copolymer, and ionomer. Optionally, the film further comprises a third layer-, adhered to a second major surface of the first layer, comprising any of the materials of the second layer.
In a second aspect, a multilayer film comprises a core layer, having two major surfaces, comprising a material selected from the grou~.~ consisting of anhydric;~e functionalizec~ poayole:_ir~, ethylene/vinyl acetate copolymer having a viny:L acetate content of between 10% and 35% by weight of the ethylene/'vi.nyl acetate copolymer, ethylene/alkyt acrylat~e copolymer having an alkyl acryla.te content of between 10% a.nd 30'% by ~Neight of tine ethylene/alky:L ac:rylat7 o:opol.ymer, etriylene/a:Lkyl methacrylate copolymer lu:aving an al.ky7_ methac~-ylate content of between 10s and 30% b~.r weight of t:he ethylene/alkyl methacrylate Copolymer, ethylene/acryl,~c: acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/crcrylic acid copolymer, ethylene/meth.acrylic a~~.~d copolymer_ having a methacrylic acid content of between 10% and 30% by weight of the ethylene/meth~~crylic a:~:id copolymer, ancx ionomer; a first outer layer, adhered t:;:~ a f:i:rst major surface of the core layer, comprz.;~ing polyrir~y:l chiari.de; and a second outer layer, adhered to a second major ~~urfa~e of the core layer, 2 ~~ comprising po:Lyolef in or polyvinyl. chloride . The first outer layer c:ompzisinc~ polyvinyl chloride can optionally have adhered vo it, a fourth layer comprising any of the materials disclosed f<.~r the core layer.
In a third aaspect, a multilayer film comprises a core layer, 'maving two cnajor surfaces, comprising polyvinyl chloride; two interme~_~iate layers, each adhered to a respective major surface of the core layer, comprising a material selected fro~i take group consisting of anhydride 2a functionalized polyolefin, ethylene/vinyl acetate copolymer having a viny:l_ acetate cement of between to o and 35°s by weight of the ethylene!vinyl acetate copolymer, ethylene/alkyl acrylate~ copolymer caving an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylatf~: copolymer, ethylene/al.kyl methacrylate ~~opolymer having an alkyl methacrylate content of between 10'o and 30% by weight of the ethylE:ne/alkyl methacrylate copolymer, E:thylene/a~~ryl.ic acid copolymer having an acrylic acid content of between loo and 30% by weight of the ethylene/a.cryli.c acid copolymer, ethylene/methacrylic ac:i.d copolymer having a methacrylic acid content of between 10~s and 30o by weight of the ethylene/methacry:Lic ac:i.d copolymer., and ionocner; and two outer layers, each adhe~:c-ed to a major :surface of a respective intermediatE_~ Layer, compris~_ng polyolefin.
In one speci:Ei.c~ aspect, the ~.nvention provides a heat shrinkable multil.ayer film r:ompr:ising (a) a first layer, having two majox: surfaces, comer=:.sing polyvinyl chloride, and (b) a second layer, adhered in a first major surfaces of the first Layer, comprising a material selected from the group consisting of: (ii anhydride functionalized polyolefin, (ii) ethyl~an~~/~w~inyl acetate copolymer having a vinyl acetate content c:>:E bet.ween 10% and 35~ by weight of 2~; the ethylene%~rinyl acetate copolymer, (_~ii) ethylene/allcyl acrylate copo:Lymer having an alkyl acrylate content of between 10o aIld 3O-°s bj~ weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 1.0'o and 30% by weight of the: ethylene/alkyl methacrylate copolymer, (v) ethylene/acrvlic acid copolymer having an acrylic acid content of between 10~ and 30°s by weight of the ethylene/acrylic acid copolymer, ;vi) ethylene/methacrylic 2b acid copolyme~:~ having ~i methacrylic: acid content of between 10% and 30% bar weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, wherein the film has a shrink tension of bet~Neen 100 and 300 psi in at least one of the machine and transverse directions at 200'F, and a free shrink of between 25'% and 65% in at least. one of the machine and transverse di-~~,~scti.ons <~t 220°F.
In <:r furvther specific aspect, the :invention provides a he<:~t shrink<a.bl.e mul.tilayer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group consisting of (i) anhydride functionalized polyole:E:iri, (ii) et~:ylene/vinyl acetate copolymer having a vin,r~l. acetate contera of between 10% and 35% by weight of the e::h.ylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alky:i acrylat:e c:~opol.ymer, (i.v) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer,. ;v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene; ac.~.ryl_ic acid copolymer, (vi) ethylene/metha.cry:lic acid copolymer having a methacryl.ic:
acid content c>f between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer; (b) a first outer layer, ac~ihered to a first major surface of. the first layer, comprising ~?o:iyvinyl chloride; and (c) a second outer layer, adhered to ;~ second major surface of the first layer, compri:~ing polyolefin or polyvinvl_ chloride; wherein 3C the film has a shrink t=ens:ion of between 100 and 300 psi_ in at least one of the mo.clnine <~nd transverse directions at 200°F, and a free shrin k: of between 2.5 ~ and 65 % in at least one of the machine and transverse dire~~tions at 220°F.
2c In a still fl.irther specific aspect, the invention provides a hear shrinkable muli=ilayer film comprising: (a) a core layer, ha,Jing two major surfaces, comprising polyvinyl chloride; (b) two intermediate layers, each adhered to a respective major surfac~~e of the core layer, comprising a material selected from the group consisting of (e) anhydride functionalized polyole_~ir~, (ii) ethylene/vinyl acetate copolymer having a viyY~l acetate conter_t of between 10% and 35% by weight of the e~hylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an a~~_kyl acryla.te content of between 10% a.nd 30'% by weight of the ethylene/alky:L acx.-ylat ' c:opolymex-, ( iv) ethylene/alkyl.
methacrylate ~_opo.l.ymer leaving an a:Lkyl methacrylate content of between 10% and 300 1>y weight of thE: ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid <content. of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/meth<~crylic acid copolymer, and (vii) ionomer; and (c) two outer: layers, each adhered to a major surface of a respective iritermediat.e layer, comprising a poiyolef i:n;
wherein the f: elm has ~~ shrink ten.~ion of between 100 and 300 psi in at least cme o1= the machine and transverse directions at 200°F, and a free ~~l~:rink of between 25% and 55 % in air least one of the machinee arid tran:werse :lirec:tions at 220°F.
In a yet further specific aspect, the invention provides a heat shrine>abl.e multilayer film comprising (a) a first layer, having t~ao major surfaces, comprising polyvinyl chloride; and. (b) a second layer, adhered to a first major surface of tl-..e first _l.~irer. , comprising a material se7.ec:ted from the group consist~i..ng of_ : (:e) a.nhydride functionalized polyolefin, (ii) ethyLelne/vinyl acetate copolymer having a 2d vinyl acetate content c~f between 10% and 35% by weight of the ethylene/viny~. acetate copolymer, (iii) et.hylene/alkyl acrylate copolymer hav:i.ng an alkyl acrylate content of between 10 % a~:ld 30% by wE:ight of the ethylene/alkyl acrylate copolymer, (i~r) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate _:c~mt.ent of between 10% and 30% by weight of the ethylene/sl.kyl. methacrylate copolymer, (v) ethylene/acrylic acid ~~opolymer having an acrylic acid content of beLweer~ 10 % a.rud 3C% by sNeight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having _~ naethacrylic acid contf~nt of between 10% and 30% by weight ~of the ethylene rtiethacrylic acid copolymer, and (vii) ionomer; wherein the film has an oxygen transmission :rate of at :l..east 100 cc/square meter-day-atmosphere in accordance' with ASTM D 3985; and wherein the film has a shrink tens:LC7r1 Uf between 100 and 300 psi in at least one of the machine' and transverse directions at 200°F, and a free shrink of bet;vveen 25 % and ~:5°-<, in at least one of the machine and transverse directions at 220°F.
In ~.nother specific aspect, the invention provides a heat shrink~~ble mutt:..:Layer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group <:or=listing of : i; anhydride functionalized polyaletun, (ii) ethylene/vinyl acetate copolymer having a viny_L acetate content of between 10% and % by weight of the e~tny:Lene/vinyl acet::ate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10 0 and 30% by weight.. of the ethylene/alkyl acrylate wopolymer, (iv) ethylene/alkyl 3C~ methacrylate copolymer l:laving an a.:Lky-'~ rnethaCrylate content of between 10'-; and 30° by weight. o:E the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acx°~Tlic acid content: of between 10% and 30 % by 2e weight of the ethylene!acrylic acid copolymer, (vi) ethylene/methacrylic ac-_~.id copolymer having a methacrylic acid content of betweerL 1.0% and 30% by weight of the ethylene/meth<~cryiic awicL copolymer:, and (vii) ionomer, (b) a first outer layer, a~=~h.ered .in a first major surface of the first layer, comprisin~_~ polyvinyl chloride; and (c) a second outer layer, :adhered t~=,~ a second major surface. of the first layer, comprising poly~:~l.efin or polyvinyl chloride; wherein the film has an oxygen t.x~ansmissio:ru rate of at, least 100 cc/square meter-day--atmosphere in accordance with ASTM D 3985; ~~nd where:i.n the film fuas a shrink tension of between 100 ar:.d 300 ps:L ~n at least one of the machine and transverse directions <:~t: 200°F, and a free shz~ink of between 25% and 55% i:n at least.. rime of tine mac~hir~e and transverse directions at 220'~'F.
DEFINITIONS
"Anhydride functionalized po:Lyolefin" (ahPO) herein refers to any 1 o:rm of anhydride functionality, such as the anhydride of malei~~ acid, itacon_ic acid, etc., grafted onto a polyole.fin or copolymerized with a polyolefin; and optionally blended with one or more polyolefins.
"Core layer" herein refers to a central layer of a multi-layer film.
"Intermediate layer" herein refers to a layer of a multilayer film which is neither a core layer nor an outer layer.
"Ionomer" herein refers to an ionized copolymer of ethylene and a vinyl monomer with an acid group, such as copolymers of acrylic or methacrylic acid, in which the ionization is a result of replacing protons with metal ions on a portion of the acid groups on the polymer.
"Outer layer" herein refers to what is typically an outermost, surface layer of a multi-layer film, although additional layers and/or films can be optionally adhered to it.
"Polymer" herein refers to homopolymer, copolymer, terpolymer, etc.
"Copolymer"
herein refers to copolymer, terpolymer, etc.
All compositional percentages used herein are calculated on a "by weight"
basis.
"Polyolefin" (PO) herein refers to the class or group of thermoplastic polymers derived from simple olefins, such as polyethylene (e.g. tow density polyethylene and high density polyethylene), polypropylene, polybutene, etc. and includes copolymers such as ethylene/aipha-olefin copolymer; ethylene/vinyl acetate copolymer;
ethylene/alkyl acrylate copolymer, ethylene/alkyl methacrylate copolymer, propylene/ethylene copolymer, and ionomer.
"Ethylene/alpha-olefin copolymer" (EAO) refers to such heterogeneous materials as linear medium density polyethylene (LMDPE), linear low density polyethylene (LLDPE), and very low and ultra low density polyethylene (VLDPE and ULDPE); as well as homogeneous polymers (HEAO) such as TAFMERT"' ethylene/alpha olefin copolymers supplied by Mitsui Petrochemical Corporation and metallocene-catalyzed polymers such as EXACTT"' materials supplied by Exxon, AFFINITY T"' resins supplied by Dow Chemical Company, and ENGAGET"' resins supplied by DuPont Dow Elastomers. These materials generally include copolymers of ethylene with one or more comonomers selected from C4 to C,o alpha-olefins such as butene-1 (i.e., 1-butane), hexane-1, octane-1, etc.
"Polyvinyl chloride" is defined herein as a polymer made by the catalytic polymerization of vinyl chloride. "Polyvinyl chloride" also includes copolymers that contain at least 50% vinyl chloride. Stabilizers, and plasticizers such as epoxidized vegetable oil, dialkyl adipate, and dialkyl phthalate, are commonly used and are herein included when referring to "polyvinyl chloride".
"Heat shrinkable" herein refers to a material which, when heated to a temperature of 180°F, will have a free shrink of 5% or greater, more preferably 10% or greater, in at least one linear direction, as measured by ASTM D 2732.
"MD" herein refers to machine direction or longitudinal direction.
"Intermediate layer" herein refers to a layer of a multilayer film which is neither a core layer nor an outer layer.
"Ionomer" herein refers to an ionized copolymer of ethylene and a vinyl monomer with an acid group, such as copolymers of acrylic or methacrylic acid, in which the ionization is a result of replacing protons with metal ions on a portion of the acid groups on the polymer.
"Outer layer" herein refers to what is typically an outermost, surface layer of a multi-layer film, although additional layers and/or films can be optionally adhered to it.
"Polymer" herein refers to homopolymer, copolymer, terpolymer, etc.
"Copolymer"
herein refers to copolymer, terpolymer, etc.
All compositional percentages used herein are calculated on a "by weight"
basis.
"Polyolefin" (PO) herein refers to the class or group of thermoplastic polymers derived from simple olefins, such as polyethylene (e.g. tow density polyethylene and high density polyethylene), polypropylene, polybutene, etc. and includes copolymers such as ethylene/aipha-olefin copolymer; ethylene/vinyl acetate copolymer;
ethylene/alkyl acrylate copolymer, ethylene/alkyl methacrylate copolymer, propylene/ethylene copolymer, and ionomer.
"Ethylene/alpha-olefin copolymer" (EAO) refers to such heterogeneous materials as linear medium density polyethylene (LMDPE), linear low density polyethylene (LLDPE), and very low and ultra low density polyethylene (VLDPE and ULDPE); as well as homogeneous polymers (HEAO) such as TAFMERT"' ethylene/alpha olefin copolymers supplied by Mitsui Petrochemical Corporation and metallocene-catalyzed polymers such as EXACTT"' materials supplied by Exxon, AFFINITY T"' resins supplied by Dow Chemical Company, and ENGAGET"' resins supplied by DuPont Dow Elastomers. These materials generally include copolymers of ethylene with one or more comonomers selected from C4 to C,o alpha-olefins such as butene-1 (i.e., 1-butane), hexane-1, octane-1, etc.
"Polyvinyl chloride" is defined herein as a polymer made by the catalytic polymerization of vinyl chloride. "Polyvinyl chloride" also includes copolymers that contain at least 50% vinyl chloride. Stabilizers, and plasticizers such as epoxidized vegetable oil, dialkyl adipate, and dialkyl phthalate, are commonly used and are herein included when referring to "polyvinyl chloride".
"Heat shrinkable" herein refers to a material which, when heated to a temperature of 180°F, will have a free shrink of 5% or greater, more preferably 10% or greater, in at least one linear direction, as measured by ASTM D 2732.
"MD" herein refers to machine direction or longitudinal direction.
"TD" herein refers to transverse direction or cross direction.
"EVA" herein refers to ethylene/vinyl acetate copolymer.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be further understood with reference to the drawings wherein Figures 1 through 4 are schematic cross-sections of various embodiments of a film of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to Figure 1, a multilayer film 10 is shown, having first layer 12 and second layer 14.
First layer t 2 comprises any of anhydride functionalized polyolefin;
ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight, preferably between 13% and 30% by weight, of the ethylene/vinyi acetate copolymer;
ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30%
by weight of the ethylene/alkyl acrylate copolymer; ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer; ethylene/acrylic acid copolymer having a acrylic acid content of between 10% and 30% by weight of the ethylene/acryiic acid copolymer;
ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer; or ionomer. Blends of any of these materials can also be used. These materials. in any combination preferably comprise at least 50%, more preferably at least 70%, and most preferably at least 90% of the first layer, and can comprise 100% of the first layer.
Second layer 14 comprises polyvinyl chloride.
Other materials can be blended with the materials of the first layer 12. These include ethylene/alpha olefin copolymer or other polymeric materials, slip and antiblock agents, stabilizers, crosslinking enhancers or inhibitors, and the like. A practical limit on the use of such materials in the first layer 12 is the degree to which interlaminar adhesion between the first layer 12, and the second layer 14, can be at least minimally maintained for commercial use.
Figure 2 shows in a first embodiment a multilayer film with first outer layer 12, core layer 14, and second outer layer 16. Layers 12 and 14 can comprise any of the materials disclosed above for layers 12 and 14 of Figure 1. Layer 16 can comprise any of the materials disclosed for layer 12 of Figure 1. Although the two outer layers 12 and 16 are preferably identical in composition, they can be different from each other, within the parameters defined herein.
In an alternative embodiment, Figure 2 represents a film in which core layer can comprise any of the materials disclosed above for layer 12 of Figure 1.
Layer 12 comprises 5 polyvinyl chloride. Layer 16 comprises a polyolefin or polyvinyl chloride.
Referring to Figure 3, the film comprises layer 34 comprising polyvinyl chloride;
layers 32 and 36 each comprising any of the materials disclosed for layer 12 of Figure 1; and layer 38 comprising a polyolefin.
Referring to Figure 4, the film comprises a core layer 44, two intermediate layers 42 and 48, and two outer layers 49 and 46. Outer layers 49 and 46 are preferably surface layers.
Core layer 44 comprises polyvinyl chloride.
Intermediate layers 49 and 46 comprise any of the materials recited above for layer 12 of Figure 1.
Outer layers 49 and 46 comprise a polyolefin. Preferred is ethylene/alpha-olefin copolymer, propylene/ethylene copolymer, ethylene/vinyl acetate copolymer, and/or ionomer.
In the five layer embodiment, the outer layers preferably differ in composition from each other, although they can be the same; the intermediate layers differ in composition from each other, although they can be the same; and the outer layers preferably differ in composition from the intermediate layers.
The invention can be further understood by reference to the examples and physical properties given below. These films can be made by a conventional flat or tubular cast coextrusion, or other suitable process such as a blown film process. If desired for a given end use, these films can be oriented by trapped bubble, tenterframe, or other suitable process. They can thereafter optionally be annealed. Films of the present invention are preferably heat shrinkable, although they can be non-heat shrinkable as well. Films of the invention can optionally be crosslinked by chemical means, or physical means such as the use of actinic radiation, preferably electron beam irradiation. Final film thicknesses can vary, depending on process, end use application, etc. Typical thicknesses are between 0.1 and 10 mils; preferably between 0.2 and 5 mils, more preferably between 0.3 mils and 3 mils, and most preferably 0.4 and 2 mils.
If oriented, the film can be oriented either monoaxially or biaxially.
Orientation ratios preferably range from 2:1 to 10:1 in each direction, more preferably 2.0:1 to 5:1 in one or both directions.
Table 1 identifies the materials used in the examples. The remaining tables describe the properties of films made with these materials.
"EVA" herein refers to ethylene/vinyl acetate copolymer.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be further understood with reference to the drawings wherein Figures 1 through 4 are schematic cross-sections of various embodiments of a film of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to Figure 1, a multilayer film 10 is shown, having first layer 12 and second layer 14.
First layer t 2 comprises any of anhydride functionalized polyolefin;
ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight, preferably between 13% and 30% by weight, of the ethylene/vinyi acetate copolymer;
ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30%
by weight of the ethylene/alkyl acrylate copolymer; ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer; ethylene/acrylic acid copolymer having a acrylic acid content of between 10% and 30% by weight of the ethylene/acryiic acid copolymer;
ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer; or ionomer. Blends of any of these materials can also be used. These materials. in any combination preferably comprise at least 50%, more preferably at least 70%, and most preferably at least 90% of the first layer, and can comprise 100% of the first layer.
Second layer 14 comprises polyvinyl chloride.
Other materials can be blended with the materials of the first layer 12. These include ethylene/alpha olefin copolymer or other polymeric materials, slip and antiblock agents, stabilizers, crosslinking enhancers or inhibitors, and the like. A practical limit on the use of such materials in the first layer 12 is the degree to which interlaminar adhesion between the first layer 12, and the second layer 14, can be at least minimally maintained for commercial use.
Figure 2 shows in a first embodiment a multilayer film with first outer layer 12, core layer 14, and second outer layer 16. Layers 12 and 14 can comprise any of the materials disclosed above for layers 12 and 14 of Figure 1. Layer 16 can comprise any of the materials disclosed for layer 12 of Figure 1. Although the two outer layers 12 and 16 are preferably identical in composition, they can be different from each other, within the parameters defined herein.
In an alternative embodiment, Figure 2 represents a film in which core layer can comprise any of the materials disclosed above for layer 12 of Figure 1.
Layer 12 comprises 5 polyvinyl chloride. Layer 16 comprises a polyolefin or polyvinyl chloride.
Referring to Figure 3, the film comprises layer 34 comprising polyvinyl chloride;
layers 32 and 36 each comprising any of the materials disclosed for layer 12 of Figure 1; and layer 38 comprising a polyolefin.
Referring to Figure 4, the film comprises a core layer 44, two intermediate layers 42 and 48, and two outer layers 49 and 46. Outer layers 49 and 46 are preferably surface layers.
Core layer 44 comprises polyvinyl chloride.
Intermediate layers 49 and 46 comprise any of the materials recited above for layer 12 of Figure 1.
Outer layers 49 and 46 comprise a polyolefin. Preferred is ethylene/alpha-olefin copolymer, propylene/ethylene copolymer, ethylene/vinyl acetate copolymer, and/or ionomer.
In the five layer embodiment, the outer layers preferably differ in composition from each other, although they can be the same; the intermediate layers differ in composition from each other, although they can be the same; and the outer layers preferably differ in composition from the intermediate layers.
The invention can be further understood by reference to the examples and physical properties given below. These films can be made by a conventional flat or tubular cast coextrusion, or other suitable process such as a blown film process. If desired for a given end use, these films can be oriented by trapped bubble, tenterframe, or other suitable process. They can thereafter optionally be annealed. Films of the present invention are preferably heat shrinkable, although they can be non-heat shrinkable as well. Films of the invention can optionally be crosslinked by chemical means, or physical means such as the use of actinic radiation, preferably electron beam irradiation. Final film thicknesses can vary, depending on process, end use application, etc. Typical thicknesses are between 0.1 and 10 mils; preferably between 0.2 and 5 mils, more preferably between 0.3 mils and 3 mils, and most preferably 0.4 and 2 mils.
If oriented, the film can be oriented either monoaxially or biaxially.
Orientation ratios preferably range from 2:1 to 10:1 in each direction, more preferably 2.0:1 to 5:1 in one or both directions.
Table 1 identifies the materials used in the examples. The remaining tables describe the properties of films made with these materials.
Examples MATERIAL TRADENAME SOURCE
PVC, ReynoldsT"' 5044 film*Reynolds PVCZ PVC 83-SHOE Unichem EVA, EIvaxT"' 3175 DuPont EVA2 EscoreneT"' LD-720.92 Exxon EVA3 EscoreneT"' LD-705.15 Exxon EMA, EMACT'"SP 1305 Chevron PO, AttaneT"' 4201 Dow pQz DowIexTM2045.03 Dow DowlexT"'2244A Dow p04 EltexTM P KS 409 Solvay * hot pressed, served as source or resin.
<remove second footnote>
PVC, = polyvinyl chloride resin derived from commercial film, as stated above.
PVCZ = polyvinyl chloride resin with approximately 13% by weight of dioctyl adipate and approximately 2% by weight or epoxidized soybean oil plasticizers.
EVA, = ethylene/vinyl acetate copolymer with 28%, by weight of the EVA, of vinyl acetate monomer.
EVAz = ethylene/vinyl acetate copolymer with 19%, by weight of the EVA, of vinyl acetate monomer.
EVAN= ethylene/vinyl acetate copolymer with 13%, by weight of the EVA, of vinyl acetate monomer.
EMA,= ethylene/methyl acrylate copolymer with 20%, by weight of the EMA, of methyl acrylate monomer.
PO, = ethylene/1-octene copolymer with a density of 0.912 grams/cc; and a melt flow index of 1Ø
POz = ethylene/1-octene copolymer with a density of 0.920 grams/cc, and 6.5%, by weight of the copolymer, of 1-octene monomer, and a melt flow index of 1.1.
PO~ = ethylene/1-octene copolymer with a density of 0.916 grams/cc, and a melt flow index of 3.3.
PVC, ReynoldsT"' 5044 film*Reynolds PVCZ PVC 83-SHOE Unichem EVA, EIvaxT"' 3175 DuPont EVA2 EscoreneT"' LD-720.92 Exxon EVA3 EscoreneT"' LD-705.15 Exxon EMA, EMACT'"SP 1305 Chevron PO, AttaneT"' 4201 Dow pQz DowIexTM2045.03 Dow DowlexT"'2244A Dow p04 EltexTM P KS 409 Solvay * hot pressed, served as source or resin.
<remove second footnote>
PVC, = polyvinyl chloride resin derived from commercial film, as stated above.
PVCZ = polyvinyl chloride resin with approximately 13% by weight of dioctyl adipate and approximately 2% by weight or epoxidized soybean oil plasticizers.
EVA, = ethylene/vinyl acetate copolymer with 28%, by weight of the EVA, of vinyl acetate monomer.
EVAz = ethylene/vinyl acetate copolymer with 19%, by weight of the EVA, of vinyl acetate monomer.
EVAN= ethylene/vinyl acetate copolymer with 13%, by weight of the EVA, of vinyl acetate monomer.
EMA,= ethylene/methyl acrylate copolymer with 20%, by weight of the EMA, of methyl acrylate monomer.
PO, = ethylene/1-octene copolymer with a density of 0.912 grams/cc; and a melt flow index of 1Ø
POz = ethylene/1-octene copolymer with a density of 0.920 grams/cc, and 6.5%, by weight of the copolymer, of 1-octene monomer, and a melt flow index of 1.1.
PO~ = ethylene/1-octene copolymer with a density of 0.916 grams/cc, and a melt flow index of 3.3.
P04 = propylene/ethylene copolymer with 3.2% ethylene by weight of the resin.
The data below demonstrates the benefits of a thermoplastic film containing polyolefin and polyvinyl chloride.
Examgle 1 A workable lab scale orientation process for purposes of evaluating the invention was determined empirically by using a T.M. Long Biaxial Film Stretcher with modifications to permit cooling of the film. Compression-molded plaques of single- and multi-layer resin formulations were stretched.
ComRression molded plaque Preparation Mono-layer PVC was made by pressing cut up pieces of Reynolds 5044 I .5 mil (150 gauge) thick film at 10,000 pounds pressure on a small CarverTM Press with 12 mil shims and a 425 ° F platen temperature. Dwell time was kept to a minimum to minimize discoloration of the PVC.
Multi-layer pressed film prototypes were made by pressing mono-layers of each resin (6 mils or greater in thickness), then cutting disks from each, assembling a stack of these, and pressing down to final thickness (10-12 mils) in the Carver press as for the mono-layer material.
Inter-ply adhesion to PVC was tested on the pressed plaques. Adhesion was poor for EVA with a vinyl acetate content of less than 10 weight percent, and LLDPE. As tie layers, EVAZ, EMA,, and EVA, were screened. Based on manually peeling apart the film layers, the best inter-piy adhesion was obtained with EVA,, so this resin was used as the tie layer.
EMA, exhibited a level of interply adhesion not as good as EVA,, but better than EVA2. The sealant layers used were PO, and POi. Under the stretching conditions used for PVC (see below), the PO, was the best sealant layer with respect to orientability.
Thus, the multilayer structure produced (Example 1 ) had the structure:
PO,/EVA,/PVC/EVA,/PO~.
Stretched Film Conditions for stretching PVC on the T.M. Long Biaxial Film Stretcher were arrived at by trial and error, comparing shrink properties of the resulting film samples to the commercial PVC shrink film (Reynolds 5044 150 gauge). The following conditions were adopted:
Rack (Orientation)Ratio: 2.6 MD x 2.6 TD.
Sample Temperature: 210° F.
Stretch Rate: 20 inches/second.
The data below demonstrates the benefits of a thermoplastic film containing polyolefin and polyvinyl chloride.
Examgle 1 A workable lab scale orientation process for purposes of evaluating the invention was determined empirically by using a T.M. Long Biaxial Film Stretcher with modifications to permit cooling of the film. Compression-molded plaques of single- and multi-layer resin formulations were stretched.
ComRression molded plaque Preparation Mono-layer PVC was made by pressing cut up pieces of Reynolds 5044 I .5 mil (150 gauge) thick film at 10,000 pounds pressure on a small CarverTM Press with 12 mil shims and a 425 ° F platen temperature. Dwell time was kept to a minimum to minimize discoloration of the PVC.
Multi-layer pressed film prototypes were made by pressing mono-layers of each resin (6 mils or greater in thickness), then cutting disks from each, assembling a stack of these, and pressing down to final thickness (10-12 mils) in the Carver press as for the mono-layer material.
Inter-ply adhesion to PVC was tested on the pressed plaques. Adhesion was poor for EVA with a vinyl acetate content of less than 10 weight percent, and LLDPE. As tie layers, EVAZ, EMA,, and EVA, were screened. Based on manually peeling apart the film layers, the best inter-piy adhesion was obtained with EVA,, so this resin was used as the tie layer.
EMA, exhibited a level of interply adhesion not as good as EVA,, but better than EVA2. The sealant layers used were PO, and POi. Under the stretching conditions used for PVC (see below), the PO, was the best sealant layer with respect to orientability.
Thus, the multilayer structure produced (Example 1 ) had the structure:
PO,/EVA,/PVC/EVA,/PO~.
Stretched Film Conditions for stretching PVC on the T.M. Long Biaxial Film Stretcher were arrived at by trial and error, comparing shrink properties of the resulting film samples to the commercial PVC shrink film (Reynolds 5044 150 gauge). The following conditions were adopted:
Rack (Orientation)Ratio: 2.6 MD x 2.6 TD.
Sample Temperature: 210° F.
Stretch Rate: 20 inches/second.
The T.M. Long Biaxial Film Stretcher had been modified to permit cooling of the samples with ambient air at the end of the stretch. Thus-prepared samples were immersed in warm water (120°F) for about 8 seconds to anneal the samples prior to testing. Samples stretched this way showed similar shrink tension properties compared with the commercial Reynolds PVC film, and somewhat higher free shrink. Multi-layer stretched films were prepared from the multi-layer pressed films by this same process. They were checked for final layer gauge. The results are as follows for Example 1 after orientation:
Table 2 Layer Layer 2 Layer 3 Layer 4 Layer S
Resin PO, EVA, PVC EVA, PO, Target 0.17 0.17 0.87 0.17 0.17 mils) Actual 0.54- 0.08-0.10 0.32-0.38 0.10-0.10 0.52-0.66 (mils) 0.65 The sealant layer was much thicker than target value, and the core much thinner, meaning that there was not as much PVC in these films as was desired. This was the result of reduced flow in the sealant during pressing of the multi-layer sample.
Because of this, we can assume that bulk properties of these films are less similar to those of PVC than they could be with more realistic layer ratios.
Testing, of Sealabilitv One inch wide test strips were cut from the stretched film, and sealed on a hot bar sealer at 350° F with 2 seconds dwell time and 40 psi pressure. Due to shrinkage, the final seal area width was less than 1" for these samples. As relates to aspects of the test not explicitly cited above, seal strength was tested on an InstronTM tester according to ASTM
F-88.
The D 940 control is an oriented, heat shrinkable three layer film with outer layers of a blend of ethylene/alpha-olefin copolymers, and a core layer of a blend of ethylene/vinyl acetate copolymer and ethylene/acrylate copolymer. The D-955 control is an oriented, heat shrinkable three layer film with outer layers of a blend of ethylene/alpha-olefin copolymers and ethylene/vinyl acetate copolymer, and a core layer of ethylene/alpha olefin copolymer.
Table 2 Layer Layer 2 Layer 3 Layer 4 Layer S
Resin PO, EVA, PVC EVA, PO, Target 0.17 0.17 0.87 0.17 0.17 mils) Actual 0.54- 0.08-0.10 0.32-0.38 0.10-0.10 0.52-0.66 (mils) 0.65 The sealant layer was much thicker than target value, and the core much thinner, meaning that there was not as much PVC in these films as was desired. This was the result of reduced flow in the sealant during pressing of the multi-layer sample.
Because of this, we can assume that bulk properties of these films are less similar to those of PVC than they could be with more realistic layer ratios.
Testing, of Sealabilitv One inch wide test strips were cut from the stretched film, and sealed on a hot bar sealer at 350° F with 2 seconds dwell time and 40 psi pressure. Due to shrinkage, the final seal area width was less than 1" for these samples. As relates to aspects of the test not explicitly cited above, seal strength was tested on an InstronTM tester according to ASTM
F-88.
The D 940 control is an oriented, heat shrinkable three layer film with outer layers of a blend of ethylene/alpha-olefin copolymers, and a core layer of a blend of ethylene/vinyl acetate copolymer and ethylene/acrylate copolymer. The D-955 control is an oriented, heat shrinkable three layer film with outer layers of a blend of ethylene/alpha-olefin copolymers and ethylene/vinyl acetate copolymer, and a core layer of ethylene/alpha olefin copolymer.
Table 3 Reynold D-940 D-955 Mono-Ply Oriented s 5044 Control Control PVC Example Control Thickness 1.5 0.6 0.75 1.5 1.5 mils _ Film MD MD MD N/A NIA
Direction Seal 1.5+/- 3.1 +/- 3.6 +/- Did not 3.6 +/-0.3 0.3 1.0 Strength 1.0 seal Ibs/in) The data in Table 3 indicate a significant improvement in sealability of the Example 1 structure compared with the mono-ply PVC and the Reynolds 5044 control, and similar to the non-PVC control films. Preferred films of the invention have a seal strength of between 2.6 and 4.6 pounds/inch.
_Shrink Tension Testing Shrink tension curves were tested on half inch strips of each film, using a shrink tension sample holder as defined in ASTM D 2838, whereby the temperature of the heating medium (silicone oil) is continually increased at about 12°F/min., then the temperature and stress at which peak shrink tension occurs is read from the curve.
Table 4 Reynolds D-940 D-955 Mono-Ply Oriented 5044 Control ControlPVC Example Control 1 Thickness 1.5 0.6 0.75 1.5 1.5 mils Film MD MD MD N/A NIA
Direction Peak Shrink182 306 425 185 175 Tension si Peak Temp. 204 199 231 199 208 F*
* temperature at which peak shank tension occurrea.
The data of Table 4 show that the low peak shrink tension of PVC shrink film is matched in the structure of Example 1. Films of the invention have a preferred peak shrink tension of between 100 and 300 psi, more preferably between 100 and 200 psi.
<removed last part(?)>
_Free Shrink Testinst Free shrink was tested at three temperatures by immersing strips of film in a hot water bath (or hot silicone oil for temperatures above the boiling point of water) for eight seconds, then determining the change in length.
Table 5 Reynolds D 40 D-955 Mono-Ply Oriented 5044 Control ControlPVC Example Control 1 Thickness 1.5 0.6 0.75 1.5 1.5 mils) Film ' MD MD MD N/A N/A
Direction Free 24 21 10 38 25 shrink @
Free 29 42 15 43 40 shrink @
Free 31 55 25 47 51 shrink @
Direction Seal 1.5+/- 3.1 +/- 3.6 +/- Did not 3.6 +/-0.3 0.3 1.0 Strength 1.0 seal Ibs/in) The data in Table 3 indicate a significant improvement in sealability of the Example 1 structure compared with the mono-ply PVC and the Reynolds 5044 control, and similar to the non-PVC control films. Preferred films of the invention have a seal strength of between 2.6 and 4.6 pounds/inch.
_Shrink Tension Testing Shrink tension curves were tested on half inch strips of each film, using a shrink tension sample holder as defined in ASTM D 2838, whereby the temperature of the heating medium (silicone oil) is continually increased at about 12°F/min., then the temperature and stress at which peak shrink tension occurs is read from the curve.
Table 4 Reynolds D-940 D-955 Mono-Ply Oriented 5044 Control ControlPVC Example Control 1 Thickness 1.5 0.6 0.75 1.5 1.5 mils Film MD MD MD N/A NIA
Direction Peak Shrink182 306 425 185 175 Tension si Peak Temp. 204 199 231 199 208 F*
* temperature at which peak shank tension occurrea.
The data of Table 4 show that the low peak shrink tension of PVC shrink film is matched in the structure of Example 1. Films of the invention have a preferred peak shrink tension of between 100 and 300 psi, more preferably between 100 and 200 psi.
<removed last part(?)>
_Free Shrink Testinst Free shrink was tested at three temperatures by immersing strips of film in a hot water bath (or hot silicone oil for temperatures above the boiling point of water) for eight seconds, then determining the change in length.
Table 5 Reynolds D 40 D-955 Mono-Ply Oriented 5044 Control ControlPVC Example Control 1 Thickness 1.5 0.6 0.75 1.5 1.5 mils) Film ' MD MD MD N/A N/A
Direction Free 24 21 10 38 25 shrink @
Free 29 42 15 43 40 shrink @
Free 31 55 25 47 51 shrink @
10 It is apparent that the PVC films exhibit a large portion of their maximum free shrink at lower temperature. This "low temperature shrink" characteristic is present in the film of Example 1 as well, though to a reduced degree.
Moduius Testinu Using ASTM D 882, the tensile modulus of the different films was determined on strips of film each having a length of 2 inches, and a width of 0.5 inches.
Table 6 Reynolds D-940 D-955 Mono-Ply Oriented 5044 Control Control PVC Example Control Thickness 1.5 0.6 0.75 1.5 1.5 mils Film MD MD MD N/A N/A
Direction Tensile 208,000 31,000 66,000 192,000 90,000 Modutus +/- 16,000+/- 2,000+/- 2,000 ( si) These results show that a desirable higher modulus is obtained with the film of Example 1 (vs. D940 and D955 controls) even though the surrounding polyolefin layers account for most of the structure and they themselves are very soft. The unique ability of PVC to afford low shrink tension with high modulus is present in the f Im of Example 1.
Tear Strenuth A final test was performed to quantify an observed improvement in tear strength for the film of Example 1 vs. the mono-ply PVC structure. This was done by using the standard tear propagation test (ASTM D 1938) on the InstronT"'tester, working with 0.5 inch samples.
Table 7 Mono-PI PVC Oriented _Exam 1e ~ 1 Thickness mils 1.5 1:5 Film N/A N/A
Direction Tear ro a ation 7.6 38.5 ms This data indicate a very significant improvement in tear resistance for the multi-ply films vs. mono-ply PVC. D-940 and D-955 show intermediate values between these two extremes, according to product data sheets.
The film of the present invention thus shows desirable aspects of PVC (low shrink tension, elastic recovery, high modulus) and desirable aspects of polyolefins (seal strength, tear resistance) by having a polyolefin as a sealant, preferably with a tie layer such as EVA
with a vinyl acetate content of between 10% and 35% by weight of the EVA, in combination with a core layer of PVC.
Example 2 A film is made like that of Example 1, but in which the sealant layer is an ethylenelalpha olefin copolymer with a melt index of 5.
Example 3 A film is made like that of Example 1, but in which the sealant layer is an ethylene/alpha olefin copolymer with a melt index of 10.
Example 4 A film is made like that of Example 1, but having the structure:
PO/ahPO/PVC/ahPO/PO
Example 5 A film is made like that of Example 1, but having the structure:
PO/ahPO/PVC/EVA,/PO
Moduius Testinu Using ASTM D 882, the tensile modulus of the different films was determined on strips of film each having a length of 2 inches, and a width of 0.5 inches.
Table 6 Reynolds D-940 D-955 Mono-Ply Oriented 5044 Control Control PVC Example Control Thickness 1.5 0.6 0.75 1.5 1.5 mils Film MD MD MD N/A N/A
Direction Tensile 208,000 31,000 66,000 192,000 90,000 Modutus +/- 16,000+/- 2,000+/- 2,000 ( si) These results show that a desirable higher modulus is obtained with the film of Example 1 (vs. D940 and D955 controls) even though the surrounding polyolefin layers account for most of the structure and they themselves are very soft. The unique ability of PVC to afford low shrink tension with high modulus is present in the f Im of Example 1.
Tear Strenuth A final test was performed to quantify an observed improvement in tear strength for the film of Example 1 vs. the mono-ply PVC structure. This was done by using the standard tear propagation test (ASTM D 1938) on the InstronT"'tester, working with 0.5 inch samples.
Table 7 Mono-PI PVC Oriented _Exam 1e ~ 1 Thickness mils 1.5 1:5 Film N/A N/A
Direction Tear ro a ation 7.6 38.5 ms This data indicate a very significant improvement in tear resistance for the multi-ply films vs. mono-ply PVC. D-940 and D-955 show intermediate values between these two extremes, according to product data sheets.
The film of the present invention thus shows desirable aspects of PVC (low shrink tension, elastic recovery, high modulus) and desirable aspects of polyolefins (seal strength, tear resistance) by having a polyolefin as a sealant, preferably with a tie layer such as EVA
with a vinyl acetate content of between 10% and 35% by weight of the EVA, in combination with a core layer of PVC.
Example 2 A film is made like that of Example 1, but in which the sealant layer is an ethylenelalpha olefin copolymer with a melt index of 5.
Example 3 A film is made like that of Example 1, but in which the sealant layer is an ethylene/alpha olefin copolymer with a melt index of 10.
Example 4 A film is made like that of Example 1, but having the structure:
PO/ahPO/PVC/ahPO/PO
Example 5 A film is made like that of Example 1, but having the structure:
PO/ahPO/PVC/EVA,/PO
Example 6 A film is made as described above for Example 1, but having the structure:
ahPO/PVC/ahPO
Example 7 A film is made as described above for Example I, but having the structure:
EV A,/PVC/EVA, Example 8 A film is made as described above for Example l, but having the structure:
ahPO/PVC/EVA, Additional examples are made as described for Example 1, but having the structures described in Table 8.
Table 8 Example Structure g EVA2/PVC/EVAZ
10 EVA~1PVC/EVA, 11 EVA,/PVC/EVA3 AhPO/PVC/EVAZ
ahPO/PVC/ahPO
Example 7 A film is made as described above for Example I, but having the structure:
EV A,/PVC/EVA, Example 8 A film is made as described above for Example l, but having the structure:
ahPO/PVC/EVA, Additional examples are made as described for Example 1, but having the structures described in Table 8.
Table 8 Example Structure g EVA2/PVC/EVAZ
10 EVA~1PVC/EVA, 11 EVA,/PVC/EVA3 AhPO/PVC/EVAZ
13 AhPO/PVC/EVA3 16 PO/ahPO/PVC/EVAZ/PO
PO/ahPO/PVC/EVA3/PO
PO/ahPO/PVC/EVA3/PO
15 Coextruded Tage Samples The following multilayer materials were prepared by coextrusion as a 5 to 6-inch wide flat sheet on a lab-scale coextrusion apparatus with a chill roll film wind-up assembly (Randcastle, Inc.):
Table 9 Film Layer Layer 2/ Layer 3/ Layer 4/ Layer 5/
Examples ThicknessThickness Thickness Thickness Thickness mils) mils mils mils) mils 1 g PO,/1.7 EVA,/1.0 PVCz/4.0 EVA,/0.9 PO~I1.9 19 P03/0. EVA,/l.l PVCZ/5.3 EVA~/0.9 PO,/1.0 Comp.l P03/1.5 EVA,/l.l POZ/4.5 EVA,/l.l PO_,/1.8 20 PO~/2.3 EVA,/0.8 PVCZ/2.6 EVA, PO~/2.6 21 P04/2.2 EVA,/0.8 PVC2/4.4 EVA,/0.8P0~/2.2 Com .2 PO~/2.3 EVA,/0.8 P02/3.8 EVA,/0.8P04/2.3 Films 18, 19, and Comp. l were irradiated with a 500 KeV electron source at a dose of 25-30 kGrays. These samples are designated as 18 EB, 19 EB, and Comp. 1 EB, respectively.
Stretched Films All of the coextruded samples in Table 9 were stretched at the following conditions on the TM Long Biaxial Film Stretcher as described in Example 1, except that warm water immersion annealing was omitted:
Rack (Orientation)Ratio: 2.6 MD x 2.6 TD.
Sample Temperature: 220°F.
Stretch Rate: 20 inches/second.
Stretched samples were then tested for shrink tension peak values and free shrink at 220°F in the machine direction as described in Example 1. Results are shown in Table 10.
Table 10 Stretched 18 18 19 19 Comp Comp 20 21 Comp2 Sample EB EB 1 .1 EB
- -Thickness l.7 1.7 1.7 1.7 1.7 1.7 I.? 1.7 1.7 mils ' Peak Shrink- 145 265 - 160 215 198 210 Tension Peak Temp.- 210 205 230 240 235 235 FZ
Free Shrink51 49 48 53 24 20 27 28 8 'highly variable (+/- z~°io) Ztemperature at which peak shrink tension occurred.
These data show that it is possible to obtain low shrink tension without the use of PVC in the core layer (the comparative film examples Comp.l EB and Comp. 2 show this effect), particularly when a low orientation ratio is used as in these examples. However, the shrinkage of the control films is seen to be reduced relative to that of the experimental dims.
Thus, in end uses where a combination of relatively tow shrink tension and relatively high free shrink is needed, films of the present invention offer great benefit compared with non-PVC films .
Preferred film of the present invention has a seal strength, when sealed to itself, of between 2 and 10 pounds/inch.
Preferred film of the present invention has, in oriented embodiments of the invention, a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F.
Preferred film of the present invention has, in oriented embodiments of the invention, a free shrink of between 25% and 65%, more preferably between 30% and 65%, most preferably between 35% and 65%, in at least one of the machine and transverse directions at 220°F
Preferred film of the present invention has a tensile modulus of between 70,000 and 200,000 psi in at least one of the machine and transverse directions Preferred film of the present invention has, in oriented embodiments of the invention, a tear propagation of between 20. and 50 grams in at least one of the machine and transverse directions.
Preferred film of the present invention has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985, more preferably between 100 and 50,000 cc/square meter-day-atmosphere.
It is to be understood that variations of the present invention as disclosed can be made without departing from the scope of the invention, which is not limited to the specific embodiments and examples disclosed herein, but extends to the claims presented below. For example, a film of the invention can comprise an A/B/A structure comprising a core layer comprising any of the materials recited for first layer 12 of Figure 1, and two outer layers each comprising polyvinyl chloride.
Examale 22 A film having the structure PVC,/EVA,/PVC, is made by the process disclosed for Example 1.
Table 9 Film Layer Layer 2/ Layer 3/ Layer 4/ Layer 5/
Examples ThicknessThickness Thickness Thickness Thickness mils) mils mils mils) mils 1 g PO,/1.7 EVA,/1.0 PVCz/4.0 EVA,/0.9 PO~I1.9 19 P03/0. EVA,/l.l PVCZ/5.3 EVA~/0.9 PO,/1.0 Comp.l P03/1.5 EVA,/l.l POZ/4.5 EVA,/l.l PO_,/1.8 20 PO~/2.3 EVA,/0.8 PVCZ/2.6 EVA, PO~/2.6 21 P04/2.2 EVA,/0.8 PVC2/4.4 EVA,/0.8P0~/2.2 Com .2 PO~/2.3 EVA,/0.8 P02/3.8 EVA,/0.8P04/2.3 Films 18, 19, and Comp. l were irradiated with a 500 KeV electron source at a dose of 25-30 kGrays. These samples are designated as 18 EB, 19 EB, and Comp. 1 EB, respectively.
Stretched Films All of the coextruded samples in Table 9 were stretched at the following conditions on the TM Long Biaxial Film Stretcher as described in Example 1, except that warm water immersion annealing was omitted:
Rack (Orientation)Ratio: 2.6 MD x 2.6 TD.
Sample Temperature: 220°F.
Stretch Rate: 20 inches/second.
Stretched samples were then tested for shrink tension peak values and free shrink at 220°F in the machine direction as described in Example 1. Results are shown in Table 10.
Table 10 Stretched 18 18 19 19 Comp Comp 20 21 Comp2 Sample EB EB 1 .1 EB
- -Thickness l.7 1.7 1.7 1.7 1.7 1.7 I.? 1.7 1.7 mils ' Peak Shrink- 145 265 - 160 215 198 210 Tension Peak Temp.- 210 205 230 240 235 235 FZ
Free Shrink51 49 48 53 24 20 27 28 8 'highly variable (+/- z~°io) Ztemperature at which peak shrink tension occurred.
These data show that it is possible to obtain low shrink tension without the use of PVC in the core layer (the comparative film examples Comp.l EB and Comp. 2 show this effect), particularly when a low orientation ratio is used as in these examples. However, the shrinkage of the control films is seen to be reduced relative to that of the experimental dims.
Thus, in end uses where a combination of relatively tow shrink tension and relatively high free shrink is needed, films of the present invention offer great benefit compared with non-PVC films .
Preferred film of the present invention has a seal strength, when sealed to itself, of between 2 and 10 pounds/inch.
Preferred film of the present invention has, in oriented embodiments of the invention, a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F.
Preferred film of the present invention has, in oriented embodiments of the invention, a free shrink of between 25% and 65%, more preferably between 30% and 65%, most preferably between 35% and 65%, in at least one of the machine and transverse directions at 220°F
Preferred film of the present invention has a tensile modulus of between 70,000 and 200,000 psi in at least one of the machine and transverse directions Preferred film of the present invention has, in oriented embodiments of the invention, a tear propagation of between 20. and 50 grams in at least one of the machine and transverse directions.
Preferred film of the present invention has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985, more preferably between 100 and 50,000 cc/square meter-day-atmosphere.
It is to be understood that variations of the present invention as disclosed can be made without departing from the scope of the invention, which is not limited to the specific embodiments and examples disclosed herein, but extends to the claims presented below. For example, a film of the invention can comprise an A/B/A structure comprising a core layer comprising any of the materials recited for first layer 12 of Figure 1, and two outer layers each comprising polyvinyl chloride.
Examale 22 A film having the structure PVC,/EVA,/PVC, is made by the process disclosed for Example 1.
Claims (17)
1. A heat shrinkable multilayer film comprising (a) a first layer, having two major surfaces, comprising polyvinyl chloride, and (b) a second layer, adhered in a first major surfaces of the first layer, comprising a material selected from the group consisting of:
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 65% in at least one of the machine and transverse directions at 220°F.
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 65% in at least one of the machine and transverse directions at 220°F.
2. The film of claim 1, further comprising a third layer, adhered to a second major surface of the first layer, comprising a material selected from the group consisting of:
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer.
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer.
3, The film of claim 1 wherein the anhydride functionalized polyolefin comprises an anhydride of maleic acid grafted onto a polyolefin.
4, The film of anyone of claims 1 to 3 wherein the film is crosslinked.
5. A heat shrinkable multilayer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group consisting of (i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer;
(b) a first outer layer, adhered to a first major surface of the first layer, comprising polyvinyl chloride; and (c)a second outer layer, adhered to a second major surface of the first layer, comprising polyolefin or polyvinyl chloride;
wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 65% in at least one of the machine and transverse directions at 22°F.
(b) a first outer layer, adhered to a first major surface of the first layer, comprising polyvinyl chloride; and (c)a second outer layer, adhered to a second major surface of the first layer, comprising polyolefin or polyvinyl chloride;
wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 65% in at least one of the machine and transverse directions at 22°F.
6, The film of claim 5 further comprising a fourth layer, adhered to the first outer layer, comprising a material selected from the group consisting of:
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer.
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer.
7. The film of claim 5 wherein the polyolefin is a material selected from the group consisting of:
(a) ethylene/alpha-olefin copolymer, (b) propylene/ethylene copolymer, (c) ethylene/vinyl acetate copolymer, and (d) ionomer.
(a) ethylene/alpha-olefin copolymer, (b) propylene/ethylene copolymer, (c) ethylene/vinyl acetate copolymer, and (d) ionomer.
8. The film of claim 7 wherein the ethylene/alpha-olefin copolymer comprises a material selected from the group consisting of;
(a) linear medium density polyethylene, (b) linear low density polyethylene, (c) very low density polyethylene, and (d) homogeneous ethylene/alpha olefin copolymer.
(a) linear medium density polyethylene, (b) linear low density polyethylene, (c) very low density polyethylene, and (d) homogeneous ethylene/alpha olefin copolymer.
9. The film of claim 8 wherein the homogeneous ethylene/alpha olefin copolymer comprises metallocene catalyzed ethylene/alpha olefin copolymer.
10. The film of any one of claims 5 to 9 wherein the film is crosslinked.
11. A heat shrinkable multilayer film comprising:
(a) a core layer, having two major surfaces, comprising polyvinyl chloride;
(b) two intermediate layers, each adhered to a respective major surface of the core layer, comprising a material selected from the group consisting of (i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer; and (c) two outer layers, each adhered to a major surface of a respective intermediate layer, comprising a polyolefin;
wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
(a) a core layer, having two major surfaces, comprising polyvinyl chloride;
(b) two intermediate layers, each adhered to a respective major surface of the core layer, comprising a material selected from the group consisting of (i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer; and (c) two outer layers, each adhered to a major surface of a respective intermediate layer, comprising a polyolefin;
wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
12. The film of claim 11 wherein the polyolefin is a material selected from the group consisting of;
(a) ethylene/alpha-olefin copolymer, (b) propylene/ethylene copolymer, (c) ethylene/vinyl acetate copolymer, and (d) ionomer.
(a) ethylene/alpha-olefin copolymer, (b) propylene/ethylene copolymer, (c) ethylene/vinyl acetate copolymer, and (d) ionomer.
13. The film of claim 12 wherein the ethylene/alpha-olefin copolymer comprises a material selected from the group consisting of:
(a) linear medium density polyethylene, (b) linear low density polyethylene, (c) very low density polyethylene, and (d) homogeneous ethylene/alpha olefin copolymer.
(a) linear medium density polyethylene, (b) linear low density polyethylene, (c) very low density polyethylene, and (d) homogeneous ethylene/alpha olefin copolymer.
14. The film of claim 13 wherein the homogeneous ethylene/alpha olefin copolymer comprises metallocene catalyzed ethylene/alpha olefin copolymer.
15, The film of any one of claims 11 to 14 wherein the film is crosslinked.
16. A heat shrinkable multilayer film comprising (a) a first layer, having two major surfaces, comprising polyvinyl chloride; and (b) a second layer, adhered to a first major surface of the first layer, comprising a material selected from the group consisting of:
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene methacrylic acid copolymer, and (vii) ionomer;
wherein the film has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985; and wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene methacrylic acid copolymer, and (vii) ionomer;
wherein the film has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985; and wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
17. A heat shrinkable multilayer film comprising (a) a core layer, having two major surfaces, comprising a material selected from the group consisting of:
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, (b) a first outer layer, adhered in a first major surface of the first layer, comprising polyvinyl chloride; and (c) a second outer layer, adhered to a second major surface of the first layer, comprising polyolefin or polyvinyl chloride;
wherein the film has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985; and wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
(i) anhydride functionalized polyolefin, (ii) ethylene/vinyl acetate copolymer having a vinyl acetate content of between 10% and 35% by weight of the ethylene/vinyl acetate copolymer, (iii) ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10% and 30% by weight of the ethylene/alkyl acrylate copolymer, (iv) ethylene/alkyl methacrylate copolymer having an alkyl methacrylate content of between 10% and 30% by weight of the ethylene/alkyl methacrylate copolymer, (v) ethylene/acrylic acid copolymer having an acrylic acid content of between 10% and 30% by weight of the ethylene/acrylic acid copolymer, (vi) ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10% and 30% by weight of the ethylene/methacrylic acid copolymer, and (vii) ionomer, (b) a first outer layer, adhered in a first major surface of the first layer, comprising polyvinyl chloride; and (c) a second outer layer, adhered to a second major surface of the first layer, comprising polyolefin or polyvinyl chloride;
wherein the film has an oxygen transmission rate of at least 100 cc/square meter-day-atmosphere in accordance with ASTM D 3985; and wherein the film has a shrink tension of between 100 and 300 psi in at least one of the machine and transverse directions at 200°F, and a free shrink of between 25% and 55% in at least one of the machine and transverse directions at 220°F.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/118,605 | 1998-07-17 | ||
| US09/118,605 US6214477B1 (en) | 1998-07-17 | 1998-07-17 | Multilayer film with polyolefin and polyvinyl chloride |
| PCT/US1999/015670 WO2000003875A2 (en) | 1998-07-17 | 1999-07-12 | Multilayer film with polyolefin and polyvinyl chloride |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2337834A1 CA2337834A1 (en) | 2000-01-27 |
| CA2337834C true CA2337834C (en) | 2003-11-04 |
Family
ID=22379641
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002337834A Expired - Fee Related CA2337834C (en) | 1998-07-17 | 1999-07-12 | Multilayer film with polyolefin and polyvinyl chloride |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US6214477B1 (en) |
| EP (1) | EP1109668A2 (en) |
| AR (1) | AR020605A1 (en) |
| AU (1) | AU4984999A (en) |
| CA (1) | CA2337834C (en) |
| TW (1) | TW500660B (en) |
| WO (1) | WO2000003875A2 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7285324B1 (en) * | 1999-09-27 | 2007-10-23 | E. I. Du Pont De Nemours And Company | Laminate structure |
| EP1268199B1 (en) | 2000-03-09 | 2004-09-15 | Reflexite Corporation | Stain resistant film construction |
| ITFI20010085A1 (en) * | 2001-05-10 | 2002-11-10 | Lorenzo Francesconi | AN EXTENDABLE FILM IN THERMOPLASTIC RESIN, USABLE FOR FOOD PACKAGES |
| US6844079B2 (en) * | 2001-06-02 | 2005-01-18 | Trespaphen Gmbh | Film having an improved sealability and adherence |
| ITFI20020213A1 (en) * | 2002-11-05 | 2004-05-06 | Lorenzo Francesconi | THERMOPLASTIC RESIN EXTENDABLE FILM USABLE FOR FOOD PACKAGES. |
| US20080182074A1 (en) * | 2007-01-31 | 2008-07-31 | Eastman Chemical Company | Rigid pvc melt bonded thermoplastic elastomer composites |
| CN103280475B (en) * | 2013-05-02 | 2016-05-04 | 宁波长阳科技有限公司 | A kind of solar cell backboard and preparation method thereof |
| EP3240688A1 (en) * | 2014-12-30 | 2017-11-08 | Dow Global Technologies LLC | Floating shrink labels |
| AU2018292028A1 (en) * | 2017-06-29 | 2019-12-05 | Cryovac, Llc | Use of dual ovenable polyester films in thermoforming packaging applications and dual ovenable thermoformed packages obtained therefrom |
| CN114375255B (en) * | 2019-09-30 | 2024-03-22 | 陶氏环球技术有限责任公司 | Multi-layer elastic films based on polyolefins |
Family Cites Families (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1130024A (en) * | 1966-05-11 | 1968-10-09 | Grace W R & Co | Improvements relating to shrink packaging |
| US4156749A (en) | 1978-01-18 | 1979-05-29 | Union Carbide Corporation | Elastic multilayer packaging film containing plasticized polyvinyl chloride |
| SE7802716L (en) * | 1978-03-09 | 1979-09-10 | Grenges Weda Ab | ADHESIVE SKIN FILM |
| US4486378A (en) | 1980-05-07 | 1984-12-04 | Toyo Seikan Kaisha Ltd. | Plastic bottles and process for preparation thereof |
| US4393106A (en) | 1980-10-31 | 1983-07-12 | Toyo Seikan Kaisha Ltd. | Laminated plastic container and process for preparation thereof |
| FR2505731A1 (en) | 1981-05-15 | 1982-11-19 | Charbonnages Ste Chimique | COMPLEX THERMOPLASTIC FILMS AND PROCESS FOR OBTAINING THEM |
| JPS5879026A (en) | 1981-11-05 | 1983-05-12 | Toyo Seikan Kaisha Ltd | Manufacture of coated plastic bottle |
| US4457960A (en) * | 1982-04-26 | 1984-07-03 | American Can Company | Polymeric and film structure for use in shrink bags |
| US4606922A (en) * | 1983-04-21 | 1986-08-19 | W. R. Grace & Co., Cryovac Div. | Cook-in meat packaging |
| US4981739A (en) * | 1989-05-22 | 1991-01-01 | International Paper Company | Oxygen impermeable leak free container |
| EP0400604B1 (en) | 1989-05-30 | 1996-01-24 | Kuraray Co., Ltd. | Multilayered structure |
| US5128176A (en) | 1990-02-05 | 1992-07-07 | Schmidt Dan R | Masking tape |
| EP0510213B1 (en) | 1990-11-14 | 1999-02-03 | Asahi Kasei Kogyo Kabushiki Kaisha | Multilayered stretchable shrink film |
| JPH04327998A (en) | 1991-04-26 | 1992-11-17 | Konica Corp | Id card and its manufacture |
| JP2784850B2 (en) | 1991-06-28 | 1998-08-06 | 富士写真フイルム株式会社 | Easy-open package for photographic photosensitive material and method for producing the same |
| US5525695A (en) * | 1991-10-15 | 1996-06-11 | The Dow Chemical Company | Elastic linear interpolymers |
| ES2096949T3 (en) * | 1992-10-02 | 1997-03-16 | Du Pont | IMPROVED RETRACTILE FILM AND PROCEDURES RELATED TO IT. |
| US5466748A (en) | 1993-03-15 | 1995-11-14 | Kuraray Co., Ltd. | Resin composition |
| US5679422A (en) * | 1995-01-25 | 1997-10-21 | American National Can Company | Coextruded film for chub packages |
| BE1009397A3 (en) * | 1995-05-12 | 1997-03-04 | Solvay | Tube or multi leaf. |
| US5679465A (en) * | 1995-10-03 | 1997-10-21 | W. R. Grace & Co.-Conn. | Vinylidene chloride composition and film with high thermal stability |
-
1998
- 1998-07-17 US US09/118,605 patent/US6214477B1/en not_active Expired - Fee Related
-
1999
- 1999-07-12 CA CA002337834A patent/CA2337834C/en not_active Expired - Fee Related
- 1999-07-12 WO PCT/US1999/015670 patent/WO2000003875A2/en not_active Application Discontinuation
- 1999-07-12 AU AU49849/99A patent/AU4984999A/en not_active Abandoned
- 1999-07-12 EP EP99933895A patent/EP1109668A2/en not_active Withdrawn
- 1999-07-16 AR ARP990103527A patent/AR020605A1/en not_active Application Discontinuation
- 1999-07-22 TW TW088112095A patent/TW500660B/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| US6214477B1 (en) | 2001-04-10 |
| AU4984999A (en) | 2000-02-07 |
| WO2000003875A2 (en) | 2000-01-27 |
| WO2000003875A3 (en) | 2000-04-20 |
| AR020605A1 (en) | 2002-05-22 |
| TW500660B (en) | 2002-09-01 |
| EP1109668A2 (en) | 2001-06-27 |
| CA2337834A1 (en) | 2000-01-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |