Siloxane resins
US6872456B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2001 |
| Grant date | Mar 29, 2005 |
| Priority date | — |
| Expiry date | Feb 2, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31663
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
This invention pertains to a siloxane resin composition comprising R1SiO3/2 siloxane units, R2SiO3/2 siloxane units and (R3O)bSiO(4-b)/2 siloxane units wherein R1 is an alkyl group having 1 to 5 carbons, hydrogen, or mixtures thereof; R2 is a monovalent organic group having 6 to 30 carbons; R3 is a branched alkyl group having 3 to 30 carbons, b is from 1 to 3; and the siloxane resin contains from 2.5 to 85 mole percent R1SiO3/2 units, 2.5 to 50 mole percent R2SiO3/2 units and 5 to 95 mole percent (R3O)bSiO(4-b)/2 units. The siloxane resin is useful to make insoluble porous resin and insoluble porous coatings. Heating a substrate coated with the siloxane resin at a sufficient temperature effects removal of the R2 and R3O groups to form an insoluble insoluble porous coating having a porosity of 1 to 60 volume percent and a dielectric constant in the range of 1.5 to 3.0.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.