Patent US4520089A successfully refreshed from Google Patents.
US4520089A
Expired / Lapsed
US
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Electrophotographic offset masters
Assignee: Mitsubishi Paper Mills Ltd
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Filing: 1983-09-19
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Granted: 1985-05-28
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Expires: 2003-09-19
Abstract
Abstract Disclosed is an electrophotographic offset master which contains sericite or sericite-containing inorganic pigment as pigment component in back coat layer. This offset master has no fogging on the photosensitive layer and thus causes no stains on printed copies.
Inventors
- 👤 Shoji Tazuki
- 👤 Koji Toyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:38
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/10; G03G5/104
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
43 words
Electrophotographic offset master which comprises a support and at least a back coat layer, a precoat layer and a photoconductive layer on said support wherein said back coat layer contains as pigment component, sericite or a pigment containing at least 30% of sericite.
Claim 2
Dependent Claim
43 words
Electrophotographic offset master which comprises a support and at least a back coat layer, a precoat layer and a photoconductive layer on said support wherein said back coat layer contains as pigment component, sericite or a pigment containing at least 30% of sericite.
Claim 3
Dependent Claim
25 words
Electrophotographic offset master according to claim 1 wherein the pigment is used in an amount of about 5 g/m 2 -about 17 g/m 2 .
Claim 4
Dependent Claim
19 words
Electrophotographic offset printing plate made by imagewise exposure of the master of claim 1 and subsequent development and fixation.
Claim 5
Dependent Claim
23 words
A method of plate making which includes the steps of imagewise exposure of the master of claim 1 and subsequent development and fixation.
Claim 6
Dependent Claim
12 words
A method of printing with the offset printing plate of claim 3.
Claim 7
Dependent Claim
15 words
A method according to claim 1 wherein there is used pure sericite as the pigment.
Claim 8
Dependent Claim
17 words
A method according to claim 1 wherein at least about 1.5 g/m 2 of sericite is used.
References Cited (Backward Citations)
US4060451A
Cited
US4427754A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-27 | 1988-11-26 | 1989-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-27 | 1992-11-26 | 1993-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-27 | 1996-11-26 | 1997-05-28 | $7700.00 | Window Closed / Lapsed |