Curable organopolysiloxane composition
US4990560A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1989 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Aug 16, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/20
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A curable organopolysiloxane composition comprising a vinyl-containing organopolysiloxane, organohydrogenpolysiloxane and platinum catalyst is proposed which is cured into a gel-like material suitable as a potting and encapsulating agent for protecting, for example, electronic components from mechanical shocks and adverse influence of the ambient atmosphere. Different from conventional similar compositions, the gelled material from the inventive composition little suffers from the problem of bleeding of oily materials contained therein on the surface. This unique advantage is obtained by using, in place of the conventional vinyl-containing organopolysiloxanes in which the vinyl groups are bonded to the silicon atoms at random position in the molecular chain, a combination of two vinyl-containing organopolysiloxanes having a specified viscosity in a limited proportion, of which one has two and only two vinyl groups in a molecular each bonded to one of the silicon atoms at the molecular chain ends and the other has one and only one vinyl group in a molecule bonded to one of the silicon atoms at the molecular chain ends alone. The composition may further contain a low-viscosity dimeth…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.