Multilayer film for reclosable package with a polyethylene layer obtained by flat sheet coextrusion
US12384133B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2021 |
| Grant date | Aug 12, 2025 |
| Priority date | — |
| Expiry date | Aug 20, 2042 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB32B2439/70
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A multilayer film comprises an adhesive layer A comprising an HMPSA composition (a); a complexable thin layer B comprising a PolyEthylene (PE) composition (b); and a heat-sealable and breakable layer C comprising a PolyEthylene (PE) composition (c). Layers B and C are bonded together by layer A. The film is characterized in that (i) the melt flow indices of compositions (b) and (c), denoted MFI(b) and MFI(c), respectively, are each between 2.5 and 15 g/10 minutes; and (ii) the melt flow index of composition (a), denoted MFI(a), is such that the ratios MFI(a)/MFI(b) and MFI(a)/MFI(c) are each between 1.5 and 10. A process for manufacturing the film comprises flat sheet coextrusion of composition (a) and of compositions (b) and (c) at a temperature of between 150° C. and 250° C. The multilayer film can be used for the manufacture of resealable packaging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.