Patent US4931841A successfully refreshed from Google Patents.
US4931841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic apparatus having abraded surface photosensitive member
Assignee: Canon Inc
•
Filing: 1987-12-23
•
Granted: 1990-06-05
•
Expires: 2007-12-23
Abstract
Abstract An electrophotographic apparatus comprises an electrophotographic photosensitive member and means for applying an electrophotographic cycle to the photosensitive member. The electrophotographic cycle includes charging, image exposure, toner development, toner transfer, remaining toner cleaning, and exposure for erasing remaining electric charge. The electrophotographic cycle application means includes abrasion means. By setting the abrasion function of the abrasion means to provide an abrasion of the surface layer of the photosensitive member at a rate of 250 Åor more per 1000 electrophotographic cycles applied to the photosensitive member, the deterioration of image quality such as image-flow and fading of images caused by succession of electrophotographic cycles is effectively prevented particularly with respect to a photosensitive member with a small diameter.
Inventors
- 👤 Toshiyuki Yoshihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:45
CPC Classifications
G; G03; G03G; G03G21/00; G03G21/0005; G03G21/0011
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
116 words
An electrophotographic apparatus comprising an electrophotographic photosensitive member and means for applying an electrophotographic cycle to the electrophotographic photosensitive member, wherein said means for applying an electrophotographic cycle includes abrasion means comprising a cleaning blade, wherein the photosensitive member is in the form of a cylinder having a diameter of 60 mm or less and comprises a laminated photosensitive surface layer including a charge generation layer and a charge transport layer, the charge generation layer having a thickness of 5 μm or less, and wherein the abrasion means causes an abrasion of the surface layer of the photosensitive member at a rate of 250 Å or more per 1000 electrophotographic cycles applied to the photosensitive member.
Claim 2
Dependent Claim
116 words
An electrophotographic apparatus comprising an electrophotographic photosensitive member and means for applying an electrophotographic cycle to the electrophotographic photosensitive member, wherein said means for applying an electrophotographic cycle includes abrasion means comprising a cleaning blade, wherein the photosensitive member is in the form of a cylinder having a diameter of 60 mm or less and comprises a laminated photosensitive surface layer including a charge generation layer and a charge transport layer, the charge generation layer having a thickness of 5 μm or less, and wherein the abrasion means causes an abrasion of the surface layer of the photosensitive member at a rate of 250 Å or more per 1000 electrophotographic cycles applied to the photosensitive member.
Claim 3
Dependent Claim
28 words
An apparatus according to claim 1, wherein said electrophotographic cycle includes charging, image exposure, toner development, toner transfer, remaining toner cleaning, and exposure for erasing remaining electric charge.
Claim 4
Dependent Claim
24 words
An apparatus according to claim 1, wherein the surface layer of the photosensitive member comprises at least a charge-transporting material and a binder resin.
Claim 5
Dependent Claim
14 words
An apparatus according to claim 1, wherein said photosensitive member comprises an organic photoconductor.
Claim 6
Dependent Claim
22 words
An apparatus according to claim 1, wherein the surface layer of the photosensitive member has a hardness of 60 g or less.
Claim 7
Dependent Claim
43 words
An apparatus according to claim 1, wherein said photosensitive member shows a change in latent image surface potential at either a dark part or a medium tone part per unit change in thickness of its surface photosensitive layer of 15 V/μm or less.
Claim 8
Dependent Claim
18 words
An apparatus according to claim 1, wherein said photosensitive member has a diameter of 30 mm or less.
Claim 9
Dependent Claim
16 words
An apparatus according to claim 1, wherein said abrasion means comprises a developer comprising the toner.
Claim 10
Dependent Claim
18 words
An apparatus according to claim 8, wherein said developer comprises a one component-type toner containing a magnetic material.
Claim 11
Dependent Claim
18 words
An apparatus according to claim 9, wherein said one component-type toner also comprises an externally added abrasive material.
Claim 12
Dependent Claim
41 words
An apparatus according to claim 1 wherein said cleaning blade comprises urethane rubber having a hardness of 60°-80°, exerts a linear pressure of 20 g/cm -40 g/cm against the photosensitive member and contacts the photosensitive member at an angle of 20°-30°.
Claim 13
Dependent Claim
22 words
An apparatus according to claim 1, wherein said electrophotographic cycle includes charging, image exposure, toner development, toner transfer and remaining toner cleaning.
References Cited (Backward Citations)
GB1397754A
Cited
US3910697A
Cited
US4279500A
Cited
US4379820A
Cited
US4543312A
Cited
GB2167199A
Cited
EP0198363A2
Cited
JPS61239279A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-04 | 1993-12-04 | 1994-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-04 | 1997-12-04 | 1998-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-04 | 2001-12-04 | 2002-06-05 | $7700.00 | Window Closed / Lapsed |