EP0338048A1 - Films polymeres - Google Patents

Films polymeres

Info

Publication number
EP0338048A1
EP0338048A1 EP88908965A EP88908965A EP0338048A1 EP 0338048 A1 EP0338048 A1 EP 0338048A1 EP 88908965 A EP88908965 A EP 88908965A EP 88908965 A EP88908965 A EP 88908965A EP 0338048 A1 EP0338048 A1 EP 0338048A1
Authority
EP
European Patent Office
Prior art keywords
film according
heat seal
density polyethylene
low density
linear low
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP88908965A
Other languages
German (de)
English (en)
Inventor
Kenneth Douglas Kendall
Darren William Dean
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Akzo Nobel Films Holding Ltd
Original Assignee
Courtaulds Films and Packaging Holdings Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Courtaulds Films and Packaging Holdings Ltd filed Critical Courtaulds Films and Packaging Holdings Ltd
Publication of EP0338048A1 publication Critical patent/EP0338048A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00Layered products comprising a layer of synthetic resin
    • B32B27/06Layered 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
    • B32B27/08Layered 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
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00Layered products comprising a layer of synthetic resin
    • B32B27/18Layered products comprising a layer of synthetic resin characterised by the use of special additives
    • B32B27/20Layered products comprising a layer of synthetic resin characterised by the use of special additives using fillers, pigments, thixotroping agents
    • B32B27/205Layered products comprising a layer of synthetic resin characterised by the use of special additives using fillers, pigments, thixotroping agents the fillers creating voids or cavities, e.g. by stretching
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00Layered products comprising a layer of synthetic resin
    • B32B27/32Layered products comprising a layer of synthetic resin comprising polyolefins
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2270/00Resin or rubber layer containing a blend of at least two different polymers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00Properties of the layers or laminate
    • B32B2307/30Properties of the layers or laminate having particular thermal properties
    • B32B2307/31Heat sealable
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00Polyalkenes
    • B32B2323/04Polyethylene
    • B32B2323/046LDPE, i.e. low density polyethylene
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00Polyalkenes
    • B32B2323/10Polypropylene

Definitions

  • This invention concerns voided polypropylene films including a heat seal layer.
  • Voided polypropylene films produced by orienting polypropylene homopolymer containing a particulate filler have found wide acceptance as packaging materials.
  • voided and non-voided polyprcpylene homopolymer layers will heat seal to themselves, the temperatures required to effect such seals cause shrinkage of the film in the region of the seal, and a distorted seal results.
  • Various polymer layers have been proposed for voided and non-voided polypropylene homopolymer films which provide the films with heat sealability at lower temperatures, thereby avoiding such shrinkage of the film.
  • layers of polymers containing units derived from at least two of ethylene, propylene and butene It has also been proposed to use blends of polymers to foris heat seal layers, for example to provide increased hot tack strength at lower temperatures.
  • a heat sealable polypropylene film comprising a layer of voided polypropylene homopolymer having a heat seal layer thereon, the heat seal layer comprising a linear low density polyethylene having a melt flow index of at least 4 as measured by ASTM D1238/73 under condition 240°C and 298.2 KPa.
  • Polypropylene films of the present invention in addition to forming good heat seals a: temperatures below those at which distortion of the seal results, have shown other advantages.
  • corona discharge treatment of the film to provide printability can be effected under less stringent conditions, thereby leading to lower odour for the treated film.
  • Heat seals produced with films of the present invention have shown good hot tack combined with good sealability.
  • the heat seal layers have shown good acceptability to cold seal adhesives. Migration of additives, for example slip and anti-static agents, from the voided homopolymer layer, has also been found to be surprisingly substantially unaffected compared with that for hitherto proposed heat seal layers.
  • the linear low density polyethylene of the heat seal layer should have a melt flow index of at least 4 as measured by ASTM D1238/73 under condition 240°C and 298.2 KPa, preferably from 5 to 7. High values of melt flow index can result in the polymer being difficult if not impossible to extrude with the polypropylene homopolymer.
  • the linear low density polyethylene preferably contains units derived from oct-1-ene.
  • the density of the polyethylene will in general be in the range of from 0.917 to 0.924 g/cm 3 .
  • a linear low density polyethylene can be used alone to produce a heat seal layer of a film in accordance with the invention
  • blends thereof with at least one further polymer can be used.
  • Preferred further polymers are ionic polymers, and in particular ionic copolymers and terpolymers. Examples of such further polymers include polymers containing units derived from ethylene, and an acrylic ester and/or maleic anhydride.
  • the weight ratio of linear low density polyethylene to the further polymer or polymers is preferably from 95:5 to 30:70, advantageously from 70:30 to 30:70, and especially about 60:40.
  • the heat seal layer is preferably from 0.5 to 5 microns thick, more particularly from 1 to 2.5 microns thick, and advantageously about 1.5 microns thick. Typical total film thicknesses are from 30 to 60 microns.
  • Heat sealable films of the present invention can, if desired, have a further heat seal layer which can be the same as or different from that already referred to.
  • a further heat seal layer which can be the same as or different from that already referred to.
  • other layers can also be present to provide the films of the present invention with particular properties, for example an adhesive layer can be present to allow the films to be laminated to other films.
  • Films of the present invention can be produced by known methods, for example by coextruding a layer of polypropylene homopolymer containing a voiding agent with a layer of linear low density polyethylene and thereafter orienting the extruded film to cause voiding of the homopolymer layer.
  • a three layer film was co-extruded at 240°C to produce a core of polypropylene homopolymer containing about 6% by weight of chalk with a layer on each side consisting of a 60:40 blend of linear low density polyethylene and an ionic polymer (a terpolymer of ethylene, an acrylic ester and maleic anhydride) to form a chill-cast web.
  • the cast web was then stretched by a ratio of 4.5:1 in the machine direction at temperature of 100°C, and thereafter by a ratio of 9.5:1 in the transverse direction at a temperature of 160°C.
  • the resultant film which had an overall thickness of 43.5 microns with a heat seal layer on each side of a voided core each of 1.5 microns thickness, showed good hot tack at low temperatures combined with good sealability.

Landscapes

  • Laminated Bodies (AREA)

Abstract

L'invention concerne des films thermosoudables de polypropylène, comprenant une couche d'homopolymère de polypropylène dotée de vides avec une couche de thermosoudage. La couche de thermosoudage comprend un polyéthylène linéaire de faible densité ayant un indice de fusion d'au moins 4 mesuré selon l'ASTM D1238/73 à 240°C et 298,2 KPa. Les scellements réalisés avec les films de la présente invention présentent un bon pouvoir collant à chaud combiné à une bonne aptitude au scellement. Les couches de thermosoudage présentent également une bonne acceptabilité à l'égard de colles de soudage à froid.
EP88908965A 1987-10-12 1988-10-11 Films polymeres Withdrawn EP0338048A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8723897 1987-10-12
GB8723897A GB2211464A (en) 1987-10-12 1987-10-12 Heat sealable polypropylene films

Publications (1)

Publication Number Publication Date
EP0338048A1 true EP0338048A1 (fr) 1989-10-25

Family

ID=10625176

Family Applications (2)

Application Number Title Priority Date Filing Date
EP88908965A Withdrawn EP0338048A1 (fr) 1987-10-12 1988-10-11 Films polymeres
EP88309477A Pending EP0312288A1 (fr) 1987-10-12 1988-10-11 Films en polymère

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP88309477A Pending EP0312288A1 (fr) 1987-10-12 1988-10-11 Films en polymère

Country Status (8)

Country Link
EP (2) EP0338048A1 (fr)
JP (1) JPH02501553A (fr)
KR (1) KR890701362A (fr)
AU (1) AU2545888A (fr)
BR (1) BR8807242A (fr)
DK (1) DK281989A (fr)
GB (1) GB2211464A (fr)
WO (1) WO1989003310A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2223446B (en) * 1988-08-26 1993-01-06 Courtaulds Films & Packaging Polymeric films for packaging
GB2224973B (en) * 1988-11-04 1992-08-19 Courtaulds Films & Packaging Polymeric films
EP0874872B2 (fr) * 1995-12-15 2007-08-15 Cryovac, Inc. Film presentant une excellente adhesivite de l'encre associee a une amelioration des proprietes de glissement, antibuee et/ou antistatiques
ITMI20011195A1 (it) 2001-06-06 2002-12-06 Veneta Decalcogomme S R L Procedimento per realizzare su un nastro di supporto flessibile una pellicola decorativa trasferibile a caldo
ITMI20040701A1 (it) * 2004-04-08 2004-07-08 Bimo Italia S P A Film compositi
EP3283384B1 (fr) * 2015-04-17 2020-12-30 Global Strategies Inc. Articles en tissu jetables tissés en rubans de haute résistance

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1157617A (fr) * 1977-12-14 1983-11-29 Milton L. Weiner Polypropylene oriente, possedant un revetement a base de copolymere polyethylenique lineaire de faible masse specifique
JPS5512008A (en) * 1978-06-29 1980-01-28 Mitsui Petrochemical Ind Packing laminate sack
FR2505731A1 (fr) * 1981-05-15 1982-11-19 Charbonnages Ste Chimique Films thermoplastiques complexes et leur procede d'obtention
GB2150881A (en) * 1983-11-23 1985-07-10 Bcl Ltd Decorative packaging films
DE3517081A1 (de) * 1985-05-11 1986-11-13 Wolff Walsrode Ag, 3030 Walsrode Opake, siegelbare mehrschichtfolien aus polyolefinen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8903310A1 *

Also Published As

Publication number Publication date
JPH02501553A (ja) 1990-05-31
WO1989003310A1 (fr) 1989-04-20
AU2545888A (en) 1989-05-02
EP0312288A1 (fr) 1989-04-19
KR890701362A (ko) 1989-12-20
GB2211464A (en) 1989-07-05
DK281989A (da) 1989-08-07
BR8807242A (pt) 1990-02-13
DK281989D0 (da) 1989-06-09
GB8723897D0 (en) 1987-11-18

Similar Documents

Publication Publication Date Title
EP1543956B1 (fr) Feuilles thermo-rétractables pour emballage ayant des propriétés scellables améliorées et articles fabriqués à partir de celles-ci.
US4340641A (en) Heat sealable packaging film comprising propylene polymer substrate and a surface layer blend of ethylene copolymer and propylene copolymer
CA1248259A (fr) Melanges de poly(alcool vinylique) et de copolymere d'ethylene et d'alcool vinylique donnant des pellicules extrudables a chaud, et resistant aux graisses
US4643945A (en) Heat sealable blend of polypropylene terpolymers and linear low density polyethylene
US4340640A (en) Heat sealable packaging film comprising propylene polymer substrate and a surface layer blend of ethylene copolymer and propylene copolymer
US4291092A (en) Heat sealable packaging film comprising propylene polymer substrate and a surface layer blend of ethylene copolymer and propylene copolymer
US5527608A (en) Oriented multilayer heat sealable packaging film capable of withstanding high altitude effects
US4275120A (en) Heat sealable packaging film comprising propylene polymer substrate and olefin surface layer blend of polybutene-1 and an ethylene or a propylene copolymer
US4297411A (en) Heat sealable packaging film comprising propylene polymer substrate and a surface layer of an ethylene copolymer and a different olefin copolymer
GB2037660A (en) Multilayered film
WO2001003921A1 (fr) Films multicouche orientes pourvus d'une couche pelliculaire de polyethylene catalyse par un metallocene
US5376437A (en) Laminated three-layer film
US4339493A (en) Heat sealable packaging film comprising propylene polymer substrate and olefin surface layer blend of polybutene-1 and an ethylene or a propylene copolymer
EP0356220B1 (fr) Pellicules polymères
US4339495A (en) Heat sealable packaging film comprising propylene polymer substrate and olefin surface layer blend of polybutene-1 and ethylene or a propylene copolymer
US4339494A (en) Heat sealable packaging film comprising propylene polymer substrate and olefin surface layer blend of polybutene-1 and an ethylene or a propylene copolymer
EP0481053B1 (fr) Materiaux d'emballage
EP0247897A1 (fr) Films scellables
EP0338048A1 (fr) Films polymeres
US5122415A (en) Sealable multilayered films with improved transparency
EP1040002B1 (fr) Films polymeres
JPH07232417A (ja) ポリオレフィン系熱収縮性積層フィルムおよびその製 造方法
EP0459742A2 (fr) Film laminé présentant une résistance à la déchirure
JP2843186B2 (ja) ヒートシール性艶消しフィルム
JPS62785B2 (fr)

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19890818

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LI NL SE

RBV Designated contracting states (corrected)

Designated state(s): AT BE CH DE ES FR GB GR IT LI NL SE

XX Miscellaneous

Free format text: VERBUNDEN MIT 88309477.3/0312288 (EUROPAEISCHE ANMELDENUMMER/VEROEFFENTLICHUNGSNUMMER) DURCH ENTSCHEIDUNG VOM 20.03.90.

17Q First examination report despatched

Effective date: 19910129

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19910809