Claims
- 1. Coupled packaging films which are impermeable to gases and vapors and consist of two olefinic polymer films, at least one of which is an oriented film, coupled to each other, with or without the interposition of an adhesive, at least one of said films being coated with a lacquer acting as a barrier for gases and vapors and metallized on the face thereof in contact with the other of said films, the lacquer being selected from the group consisting of vinylidene copolymers having a content in vinylidene units greater than 75% by weight and polymeric mixtures containing polyvinyl alcohol of medium to high degree of hydrolysis.
- 2. Coupled films according to claim 1, characterized in that the oriented film is obtained by extrusion and stretching of polypropylene consisting prevailingly of isotactic macro-molecules and having a melt index comprised between 0.5 and 5.
- 3. Coupled films according to claim 1, characterized in that they consist of two olefinic polymer films coupled to each other, one of said films being an oriented film of polypropylene and the other film being a non-oriented film obtained by the extrusion of polypropylene, polyethylene, crystalline propylene-ethylene copolymers with a prevailing content in propylene, mixtures of polyethylene and polypropylene with each other or mixtures of said homopolymers with other polymers or copolymers.
- 4. Coupled fixtures according to claim 3, characterized in that a non-oriented film is used and obtained by extrusion of a crystalline random propylene-ethylene copolymer with a prevailing propylene content.
- 5. Coupled films according to claim 1, characterized in that a non-oriented film is used and obtained by extrusion of a crystalline block propylene-ethylene copolymer with a prevailing propylene content.
- 6. Coupled films according to claim 3, characterized in that a non-oriented film is used and obtained by extrusion of a mixture selected from the group consisting of mixtures of polypropylene or polyethylene with ethylene-propylene copolymers and mixtures of said homopolymers with ethylene-vinyl acetate copolymers.
- 7. Coupled films according to claim 1, characterized in that the lacquer acting as barrier to gases and vapors consists of vinylidene copolymers having a content in vinylidene units greater than 75% by weight.
- 8. Coupled films according to claim 7, characterized in that the vinylidene copolymer is selected from the group consisting of vinylidene chloride/acrylonitrile copolymers and vinylidene/methylmethacrylate copolymers.
- 9. Coupled films according to claim 1, characterized in that the lacquer acting as barrier to gases and vapors consists of a polymeric mixture containing polyvinyl-alcohol of medium or high degree of hydrolysis.
- 10. Coupled films according to claim 9, characterized in that the lacquer acting as barrier to gases and vapors is a polymeric mixture comprising polyvinyl-alcohol and a polyalkyleneimine.
- 11. Coupled films according to claim 10, in which the polyalkyleneimine of the polymeric mixture is polyethyleneimine.
- 12. Coupled films according to claim 10, in which the polyalkyleneimine of the polymeric mixture is polypropyleneimine.
- 13. Coupled films according to claim 1, characterized in that the lacquer is applied on the oriented film after pretreatment of said film by continuous, non-perforating electrical discharges, by an oxidizing flame or by a chemical oxidizing system.
- 14. Coupled films according to claim 1, characterized in that the thickness of the lacquer coating is comprised between 1 and 20 micron.
- 15. Coupled films according to claim 1, characterized in that the metallization is carried out with aluminum, under vacuum and for a thickness corresponding to a superficial resistivity comprised between 1 and 5 Ohm.
- 16. Coupled films according to claim 1, characterized in that the metallized film is printed with inks.
- 17. Coupled films according to claim 1, characterized in that the two films are coupled together by means of an adhesive selected from the group of synthetic adhesive consisting of thermoplastic resins and hot-melts.
- 18. Coupled films according to claim 1, characterized in that the two films are coupled together by means of extrusion coating.
Priority Claims (1)
Number |
Date |
Country |
Kind |
25289 A/81 |
Nov 1981 |
ITX |
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Parent Case Info
This is a continuation of application Ser. No. 707,833, filed Mar. 4, 1985 which in turn is a continuation of Ser. No. 444,516 filed Nov. 26, 1982 and now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4211811 |
Montedison |
Jan 1981 |
|
4261473 |
Yamada et al. |
Apr 1981 |
|
4578294 |
Ouchi et al. |
Mar 1986 |
|
Continuations (2)
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Number |
Date |
Country |
Parent |
707833 |
Mar 1985 |
|
Parent |
444516 |
Nov 1982 |
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