Extrusion coating compositions and method
US6458439B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 1999 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Mar 16, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31681
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Solid extrusion coating compositions for metal substrates, a method of extrusion coating a metal substrate, and a metal article are disclosed. The extrusion coating composition is a thermoplastic material and comprises: (a) a first polyester having a weight average molecular weight of about 10,000 to about 80,000 and a Tg of greater than 45° C. to about 100° C., (b) a second polyester having a weight average molecular weight of about 10,000 to about 70,000 and a Tg of about −10° C. to about 45° C., and optionally, (c) a modifying resin, such as an epoxy resin having an epoxy equivalent weight of about 500 to about 15,000, wherein the Tg of the first and second polyesters differ by about 5 C.° to about 60 C.°. The extrusion coating composition is applied to a metal substrate in an extrusion process to provide a composition film having a thickness of about 1 to about 40 microns.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.