Method and apparatus for applying coatings of molten thermoplastic material over closed pore elastomer foam substrates
US6776948B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2001 |
| Grant date | Aug 17, 2004 |
| Priority date | — |
| Expiry date | Nov 2, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C44/569
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In order to make weather seals from closed cell elastomer foam material, molten plastic is extruded over a substrate of the foam material. Surface reactions during extrusion are avoided by continuously pulling the substrate through an oven chamber to degas (and remove moisture from) the material at least on its outside to a limiting thickness of the order of 10-30 mil to form a skin or crust. The extrusion of the over-coating is carried out to form a sleeve while the substrate is still hot. Since the skin is a degassed region on the outside of the foam substrate, reactions which may cause blistering and prevent the extrusion of a smooth and firmly adhering skin are avoided. The substrate material is preferably a thermosetting EPDM rubber closed cell foam, and the over coating material is a thermoplastic elastomer (TPE).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.