Process for forming multi-layer molded articles
US8029718B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2007 |
| Grant date | Oct 4, 2011 |
| Priority date | — |
| Expiry date | Apr 4, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1352
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention relates to a rotomolding process for forming a multi-layer article of two different polymers with different melting points in which an outer layer polymer powder is added to a rotational molder along with an inner layer polymer powder that is separated from the outer layer powder by a release film. The release film has a particular melting point that is greater than that of the outer layer polymer and preferably between the melting points of the inside layer and outside layer polymers. In one embodiment, the release layer forms an enclosure or bag in which the inner layer (higher melting point) powder is enclosed. In another embodiment the release film forms a barrier between an insulated cavity and the mold. The process provides a means for a “one-shot” rotomolding method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.