US5834584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicone rubber roller for electrophotography and method of producing the same
Assignee: Sumitomo Rubber Industries Ltd
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Filing: 1995-04-25
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Granted: 1998-11-10
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Expires: 2015-04-25
Abstract
Abstract An electrically conductive rubber roller for electrophotography which does not exhibit touch memory or bleed out of remnant siloxanes, even after 18 days of storage without use, and, in a preferred form, exhibits little change in electric resistance with changes in environment. This roller is made by making a rubber molding material composition containing a raw polysiloxane rubber which does not contain more than 5,000 ppm of low molecular weight polysiloxanes, cyclic siloxanes and non-functional silicone oils (remnant siloxanes); molding this composition into a roller; at least primarily crosslinking the rubber in the roller; and then subjecting the crosslinked rubber roller to heating under a vacuum.
Inventors
- 👤 Hitoshi Itani
- 👤 Yuji Yamasaki
- 👤 Hirotoshi Murakami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:53
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/1665; G03G15/167; G03G15/1685; C; C08; C08G; C08G77/00; C08G77/04; C08G77/32; C08G77/34; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0233
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
140 words
A method of producing a rubber roller for use in electrophotography comprising: forming a composition comprising a base polymer comprising a polysiloxane raw rubber containing not more than 5,000 ppm of remnant siloxanes, said remnant siloxanes consisting of: polysiloxanes having a polymerization degree of not more than 25; cyclic siloxanes; and non-functional silicone oils; crosslinking and molding said composition into the form of an intermediate roller; and then subjecting said intermediate roller to heating under a vacuum of not more than 5 mm Hg under such a combination of conditions as to produce a final roller which, after 18 days of storage, exhibits slight touch memory or no touch memory on a first copy sheet of paper and no touch memory at the latest on a third copy sheet of paper, and which is substantially free of said remnant siloxanes.
Claim 2
Independent Claim
140 words
A method of producing a rubber roller for use in electrophotography comprising: forming a composition comprising a base polymer comprising a polysiloxane raw rubber containing not more than 5,000 ppm of remnant siloxanes, said remnant siloxanes consisting of: polysiloxanes having a polymerization degree of not more than 25; cyclic siloxanes; and non-functional silicone oils; crosslinking and molding said composition into the form of an intermediate roller; and then subjecting said intermediate roller to heating under a vacuum of not more than 5 mm Hg under such a combination of conditions as to produce a final roller which, after 18 days of storage, exhibits slight touch memory or no touch memory on a first copy sheet of paper and no touch memory at the latest on a third copy sheet of paper, and which is substantially free of said remnant siloxanes.
Claim 3
Dependent Claim
31 words
A method of forming a roller for use in electrophotography as claimed in claim 1, further comprising secondarily crosslinking said intermediate roller prior to heating said intermediate roller in a vacuum.
Claim 4
Dependent Claim
52 words
A method of forming a roller for use in electrophotography as claimed in claim 1, wherein said composition further comprises about 18 to 28 parts by weight of particulate silica and about 5 to 12 parts by weight of conductive carbon, respectively per 100 parts by weight of said polysiloxane raw rubber.
Claim 5
Dependent Claim
41 words
A method of forming a roller for use in electrophotography as claimed in claim 1, wherein said composition further comprises a foaming agent, and said method further comprises causing said composition to foam into a sponge form prior to said crosslinking.
Claim 6
Dependent Claim
52 words
A method of forming a roller for use in electrophotography as claimed in claim 1, further comprising, in addition, and subsequent to said heating under a vacuum, extracting said roller with at least one solvent for said remnant siloxanes to assist in reducing the content of said remnant siloxanes in said roller.
Claim 7
Dependent Claim
36 words
A method as recited in claim 1, wherein said roller, after 72 hours of storage without use, allows at the worst only slight touch memory of average brightness 63-68 on a first copy sheet of paper.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-09 | 2002-05-11 | 2002-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-09 | 2006-05-11 | 2006-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-09 | 2010-05-11 | 2010-11-10 | $7700.00 | Window Closed / Lapsed |