EP0572020A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Image forming apparatus
Assignee: Sharp Corp
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Filing: 1993-05-27
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Granted: —
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Expires: 2013-05-27
Abstract
Abstract The object of the invention to provide an image forming apparatus of electrophotographic type equipped with a conductive contact type transfer roller (6), wherein failure in transfer can be prevented which is caused by a lowering of resistance due to absorption of a recording sheet (5) exposed in a high temperature and high humidity environment. The image forming apparatus of electrophotographic type equipped with a conducive contact type transfer device, is made up with a fixing heat roller assembly (7) that has a volume resistivity of 10⁹ Ω·cm or more.
Inventors
- 👤 Koichi Inui
- 👤 Shirou Wakahara
- 👤 Hideo Yamasa
- 👤 Fumio Shimazdu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 04:53
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
32 words
An image forming apparatus of electrophotographic type comprising a conductive contact type transfer device, being characterized in that a fixing heat roller assembly has a volume resistivity of 10⁹ Ω·cm or more.
Claim 2
Dependent Claim
23 words
An image forming apparatus according to Claim 1, wherein said fixing roller assembly comprises a roller for heating and a roller for pressing.
Claim 3
Dependent Claim
29 words
An image forming apparatus according to Claim 2, wherein said roller for heating includes a layer for separation disposed on its surface layer and a heater means built therein.
Claim 4
Dependent Claim
29 words
An image forming apparatus according to Claim 3, wherein said layer for separation comprises a coating of an insulating material having a volume resistivity of 10⁹ Ω·cm or more.
Claim 5
Dependent Claim
16 words
An image forming apparatus according to Claim 4 wherein said roller for pressing comprises silicone roller.
Claim 6
Dependent Claim
41 words
An image forming apparatus according to Claim 1, wherein a recording sheet on which an image is formed has a length in its conveying direction equal to or larger than the distance between said transfer device and said fixing roller assembly.
References Cited (Backward Citations)
No citation records indexed.
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