Heat-sealed closure for polyester container
US5721028A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1993 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Jan 5, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31522
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention provides a strong heat seal to a thermoplastic polyester container which can withstand hot water treatment such as retorting, and to a heat sealed container. A heat-sealable closure is also provided. It is composed of a laminate consisting of a heat-seal layer comprising as a main component a copolymerized polyester resin having a softening temperature of 120.degree. C. and a glass-transition temperature of 30.degree. to 85.degree. C., a metal substrate, and an epoxy-phenol resin primer layer interposed between them. Preferably, the container has a heat seal portion composed of a thermoplastic polyester having a fusion temperature in the crystalline state of at least 200.degree. C. This polyester portion is oriented and crystallized or heat-crystallized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.