Use of silicone compositions cross-linkable by cationic process under UV radiation and of an onium borate type photoinitiator for coating flat joints, particularly cylinder head gaskets
US6423378B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1999 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Aug 30, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2003/1096
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention concerns the use of cross-linkable silicone compositions for fast, economical and simple impregnation and/or varnishing of flat joints (e.g. cylinder head gaskets). More precisely it concerns the use of silicone compositions cross-linkable under UV radiation, by cationic process and in the presence of specific phoinitiators selected among onium borates or organometallic complexes, of which the borate counter-anions contain at least a boron bound to at least a substituted phenyl (Me, F). The silicone liquid precursor is a polydimethylsiloxane (PDMS) substituted by cross-linking functional groups, by cationic process (Gfp) under UV of the epoxy of vinyloxy type. These Gfp are present at the rate of 0.15 to 2.0 pr kg of PDMS. The invention also relates to the method for impregnating/varnishing flat joints (e.g. cylinder head gaskets) using the specific PDMS composition+photoinitiator of borate type as well as the treated joints and the composition themselves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.