Heat-shrinkable multi-layer film for deep-draw forming, and process for production thereof
US9352395B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2010 |
| Grant date | May 31, 2016 |
| Priority date | — |
| Expiry date | Sep 11, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2495
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A polyamide resin-based heat-shrinkable multilayer film having excellent heat shrinkability and strength, as well as a high degree of deep A polyamide resin-based heat-shrinkable multilayer film having excellent heat shrinkability and strength, as well as a high degree of deep drawability as represented a shorter side-basis draw ratio (D/L) in excess of 0.6 between a maximum draw depth (D) and a shorter side length (L) of a mold opening is provided. The multilayer film is characterized by including a surface layer (a) comprising a thermoplastic resin, an intermediate layer (b) comprising a polyamide resin, and a surface layer (c) comprising a sealable resin, wherein (A) the intermediate layer (b) comprises a mixture of an aliphatic polyamide having a melting point of at least 180° C., and an amorphous aromatic polyamide comprising a polycondensation product of an aliphatic diamine with is ophthalmic acid and terephthalic acid as main acid components, including 25-45 wt. % of the amorphous aromatic polyamide, and has a thickness exceeding 25% and at most 50% of a total thickness of whole layers, and exhibiting: (B) tensile stresses at an elongation of 100% as measured in a tensile t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.