US4603087A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fixing roll
Assignee: Ricoh Co Ltd
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Filing: 1984-11-09
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Granted: 1986-07-29
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Expires: 2004-11-09
Abstract
Abstract A fixing roll which comprises crosslinking a rubber compound containing a methyl vinyl system silicone raw rubber and silica so as to have a crosslinking density of 6×10 -4 mole/cc and forming a coated layer.
Inventors
- 👤 Hideaki Ema
- 👤 Yasuo Hirano
- 👤 Kazuo Nojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:13
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053; G03G15/2057; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1355; Y10T428/31504; Y10T428/31652; Y10T428/31663
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
In a fixing roll for electrophotography comprising a metal core and a silicone rubber surface layer, the improvement which comprises: said silicon rubber surface layer is a heat-cured, crosslinked, silicone rubber composition having a crosslinking density of at least 6×10 -4 mole/cc measured by the toluene swelling method, said silicone rubber composition having been prepared by incorporating a peroxide crosslinking agent into a blend consisting essentially of silica and a polysiloxane polymer consisting essentially of recuring units of the formulas ##STR2## and heating said blend to a crosslinking temperature effective to convert said blend to said heat-cured, crosslinked, silicone rubber composition.
Claim 2
Dependent Claim
101 words
In a fixing roll for electrophotography comprising a metal core and a silicone rubber surface layer, the improvement which comprises: said silicon rubber surface layer is a heat-cured, crosslinked, silicone rubber composition having a crosslinking density of at least 6×10 -4 mole/cc measured by the toluene swelling method, said silicone rubber composition having been prepared by incorporating a peroxide crosslinking agent into a blend consisting essentially of silica and a polysiloxane polymer consisting essentially of recuring units of the formulas ##STR2## and heating said blend to a crosslinking temperature effective to convert said blend to said heat-cured, crosslinked, silicone rubber composition.
Claim 3
Dependent Claim
41 words
A fixing roll as claimed in claim 1 in which said polysiloxane polymer, when free of silica, is capable of having a crosslinking density, measured by the toluene swelling method, in the range of from 1×10 -4 to 2×10 -4 mole/cc.
Claim 4
Dependent Claim
20 words
A roll according to claim 1 wherein said crosslinking density is in the range of 6×10 -4 -10×10 -4 mole/cc.
Claim 5
Dependent Claim
20 words
A roll according to claim 1 wherein said crosslinking density is in the range of 6×10 -4 -8×10 -4 mole/cc.
Claim 6
Dependent Claim
24 words
A roll according to claim 1 wherein the amount of silica in said silicon rubber composition is in the range of 30-60 wt. %.
Claim 7
Dependent Claim
16 words
A roll according to claim 1 wherein said silica is either wet silica or dry silica.
References Cited (Backward Citations)
GB1458694A
Cited
US3988817A
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GB1502450A
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GB1503704A
Cited
US4074001A
Cited
US4313981A
Cited
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Cited
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US4357388A
Cited
US4360566A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-28 | 1990-01-27 | 1990-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-28 | 1994-01-27 | 1994-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-28 | 1998-01-27 | 1998-07-29 | $7700.00 | Window Closed / Lapsed |