US4800124A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silcone elastomer-forming compositions
Assignee: Dow Silicones UK Ltd
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Filing: 1987-06-25
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Granted: 1989-01-24
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Expires: 2007-06-25
Abstract
Abstract A composition which is curable to an elastomer comprising (1) a siloxane gum having a Williams plasticity of at least 100 mm/100 at 25° C., (2) a reinforcing silica filler, (3) a copolymer of R 3 SiO 0 .5 units and SiO 2 units in which R represent a monovalent hydrocarbon group having less than 7 carbon atoms, (4) mica and (5) an organic peroxide curing agent. The compositions are useful for providing fire resistant insulation on electrical equipment.
Inventors
- 👤 James H. Davis
- 👤 Michael J. Dams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:25
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/46; C; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C08K5/00; C08K5/04; C08K5/14; C08L; C08L83/00; C08L83/04; C08G; C08G77/00; C08G77/04; C08G77/14; C08G77/16; C08G77/20; C08G77/22; C08G77/24; C08G77/42; C08G77/44; C08G77/70; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2962; Y10T428/31504; Y10T428/31652; Y10T428/31663
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
126 words
A composition curable to an elastomer and which comprises (1) a polydiorganosiloxane gum wherein at least 50 percent of the total organic substituents are methyl groups, up to 2.5 percent of the total substituents are vinyl groups and any remaining substituents are selected from phenyl and 3,3,3-trifluoropropyl groups, the gum having a Williams plasticity of at least 100 mm/100 at 25° C., (2) a reinforcing silica filler, (3) a copolymer of R 3 SiO 0 .5 units and SiO 2 units wherein each R represents a monovalent hydrocarbon group having less than 7 carbon atoms and the ratio of R 3 SiO 0 .5 units to SiO 2 units is in the range from 0.5:1 to 1.2:1, (4) mica and (5) an organic peroxide curing agent.
Claim 2
Dependent Claim
126 words
A composition curable to an elastomer and which comprises (1) a polydiorganosiloxane gum wherein at least 50 percent of the total organic substituents are methyl groups, up to 2.5 percent of the total substituents are vinyl groups and any remaining substituents are selected from phenyl and 3,3,3-trifluoropropyl groups, the gum having a Williams plasticity of at least 100 mm/100 at 25° C., (2) a reinforcing silica filler, (3) a copolymer of R 3 SiO 0 .5 units and SiO 2 units wherein each R represents a monovalent hydrocarbon group having less than 7 carbon atoms and the ratio of R 3 SiO 0 .5 units to SiO 2 units is in the range from 0.5:1 to 1.2:1, (4) mica and (5) an organic peroxide curing agent.
Claim 3
Dependent Claim
40 words
A composition as claimed in claim 1 wherein the silicon-bonded organic substituents in polydiorganosiloxane (1) are methyl, vinyl and optionally phenyl groups, the vinyl groups being present in an amount of from 0.01 to 0.5 percent of the total substituents.
Claim 4
Dependent Claim
24 words
A composition as claimed in claim 2 wherein the polydiorganosiloxane gum (1) has a Williams plasticity in the range from 125 to 185 mm/100.
Claim 5
Dependent Claim
30 words
A composition as claimed in claim 3 wherein there is additionally present a polydiorganosiloxane liquid (6) having a viscosity in the range from 0.5 to 50 Pa.s at 25° C.
Claim 6
Dependent Claim
13 words
The product obtained by the process of curing the composition of claim 1.
Claim 7
Dependent Claim
24 words
An insulated electrical conductor wherein at least a part of the insulation consists of the cured product of the composition claimed in claim 1.
References Cited (Backward Citations)
GB1097629A
Cited
US3772239A
Cited
GB1551475A
Cited
JPS5316758A
Cited
GB2046771A
Cited
US4269757A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-24 | 1992-07-25 | 1993-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-24 | 1996-07-25 | 1997-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-24 | 2000-07-25 | 2001-01-24 | $7700.00 | Window Closed / Lapsed |