US5352731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermally conductive silicone rubber composition containing organo polysiloxanes with high and low polymerization degrees and spherical aluminum oxide powder
Assignee: Shin-Etsu Chemical Co Ltd
•
Filing: 1993-09-01
•
Granted: 1994-10-04
•
Expires: 2013-09-01
Abstract
Abstract A silicone rubber composition having thermal conductivity higher than 5x10-3 cal/cmxsecx DEG C. and excellent workability in various molding processes, which comprises A) 95-50 parts by weight of an organopolysiloxane having an average polymerization degree of 6,000-12,000, B) 5-50 parts by weight of an organopolysiloxane having an average polymerization degree of 200-2,000, C) 500-1,200 parts by weight of a spherical aluminum oxide powder and D) a curing agent ample for curing the composition consisting of A) to C) .
Inventors
- 👤 Akio Nakano
- 👤 Tsutomu Yoneyama
- 👤 Nobumasa Tomizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:30
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08L; C08L83/00; C08L83/04; C08G; C08G77/00; C08G77/04; C08G77/20; C08G77/22; C08G77/24; C08G77/70
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
106 words
A thermally conductive silicone rubber composition having thermal conductivity of 5×10 -3 ·cal/cm·sec·°C. or higher which consists essentially of A 95-50 parts by weight of a gummy organopolysiloxane having an average polymerization degree of 6,000-12,000, B) 5-50 parts by weight of an oily organpolysiloxane having an average polymerization degree of 200-2,000 and a viscosity of 600 to 120,000 centistokes, C) 500-1,200 parts by weight of a spherical aluminum oxide powder having an average particle size of 50 μum or less and an average major axis diameter/minor axis diameter ratio of 1.0 to 1.4, and D) a curing agent in an amount sufficient to cure the composition.
Claim 2
Dependent Claim
106 words
A thermally conductive silicone rubber composition having thermal conductivity of 5×10 -3 ·cal/cm·sec·°C. or higher which consists essentially of A 95-50 parts by weight of a gummy organopolysiloxane having an average polymerization degree of 6,000-12,000, B) 5-50 parts by weight of an oily organpolysiloxane having an average polymerization degree of 200-2,000 and a viscosity of 600 to 120,000 centistokes, C) 500-1,200 parts by weight of a spherical aluminum oxide powder having an average particle size of 50 μum or less and an average major axis diameter/minor axis diameter ratio of 1.0 to 1.4, and D) a curing agent in an amount sufficient to cure the composition.
Claim 3
Dependent Claim
48 words
The thermally conductive silicone rubber composition of claim 1, wherein said organopolysiloxane of component A) is represented by an average compositional formula, R n Si O .sub.(4-n)/z, wherein R is a monovalent substituted or unsubstituted hydrocarbon residue, and n is an positive number ranging from 1.95 to 2.05.
Claim 4
Dependent Claim
19 words
The thermally conductive silicone rubber composition of claim 2, wherein the main chain of said organopolysiloxane comprises dimethylsiloxane units.
Claim 5
Dependent Claim
31 words
The thermally conductive silicone rubber composition of claim 3, wherein part of the methyl groups of said main chain are replaced by vinyl groups, phenyl groups, trifluoropropyl groups or combinations thereof.
Claim 6
Dependent Claim
53 words
The thermally conductive silicone rubber composition of claim 2, wherein said monovalent hydrocarbon residue represented by R is an unsubstituted alkyl group, a halogenated alkyl group, an unsubstituted cycloalkyl group, a halogenated cycloalkyl group, an unsubstituted alkenyl group, a halogenated alkenyl group, an unsubstituted aryl group, a halogenated aryl group or combinations thereof.
Claim 7
Dependent Claim
40 words
The thermally conductive silicone rubber composition of claim 5, wherein said alkyl group is methyl, ethyl or propyl, said cycloalkyl group is cyclopentyl or cyclohexyl, said alkenyl group is vinyl or allyl, and said aryl group is phenyl or tolyl.
Claim 8
Dependent Claim
20 words
The thermally conductive silicone rubber composition of claim 5, wherein the halogen of said halogenated groups is chlorine or fluorine.
Claim 9
Dependent Claim
49 words
The thermally conductive silicone rubber composition of claim 1, wherein said organopolysiloxane of component B) is represented by an average compositional formula, R n Si O 4-n )/z wherein R is a monovalent substituted or unsubstituted hydrocarbon residue, and n is a positive number ranging from 1.95 to 2.05.
Claim 10
Dependent Claim
19 words
The thermally conductive silicone rubber composition of claim 8, wherein the main chain of said organopolysiloxane comprises dimethylsiloxane units.
Claim 11
Dependent Claim
31 words
The thermally conductive silicone rubber composition of claim 3, wherein part of the methyl groups of said main chain are replaced by vinyl groups, phenyl groups, trifluoropropyl groups or combinations thereof.
Claim 12
Dependent Claim
53 words
The thermally conductive silicone rubber composition of claim 2, wherein said monovalent hydrocarbon residue represented by R is an unsubstituted alkyl group, a halogenated alkyl group, an unsubstituted cycloalkyl group, a halogenated cycloalkyl group, an unsubstituted alkenyl group, a halogenated alkenyl group, an unsubstituted aryl group, a halogenated aryl group or combinations thereof.
Claim 13
Dependent Claim
41 words
The thermally conductive silicone rubber composition of claim 11, wherein said alkyl group is methyl, ethyl or propyl, said cycloalkyl group is cyclopentyl group or cyclohexyl, said alkenyl group is vinyl or allyl, and said aryl group is phenyl or tolyl.
Claim 14
Dependent Claim
20 words
The thermally conductive silicone rubber composition of claim 11, wherein the halogen of said halogenated groups is chlorine or fluorine.
Claim 15
Dependent Claim
26 words
The thermally conductive silicone rubber composition of claim 1, wherein the mixing ratio of said component A) to said component B) ranges from 95/5 to 50/50.
Claim 16
Dependent Claim
43 words
The thermally conductive silicone rubber composition of claim 1, wherein said spherical aluminum oxide powder of component C) is an aluminum oxide powder prepared by process comprising a step of melting metallic aluminum and a step of oxidizing molten metallic aluminum with oxygen.
Claim 17
Dependent Claim
16 words
A curable silicone rubber article produced by molding a thermally conductive silicone composition of claim 1.
Claim 18
Dependent Claim
14 words
A cured silicone rubber article produced by heat curing an article of claim 16.
Claim 19
Dependent Claim
13 words
The silicone rubber article of claim 17 in the form of a sheet.
References Cited (Backward Citations)
US4355129A
Cited
US4444944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-10-03 | 1998-04-04 | 1998-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-03 | 2002-04-04 | 2002-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-03 | 2006-04-04 | 2006-10-04 | $7700.00 | Window Closed / Lapsed |