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US4461818A
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Method for making printing plates employing an organic photo-conductive compound and a styrene-maleic anhydride half ester as a binder
Assignee: Mitsubishi Paper Mills Ltd
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Filing: 1982-09-24
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Granted: 1984-07-24
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Expires: 2002-09-24
Abstract
Abstract Disclosed is a method for making a printing plate which comprises forming a toner image by electrophotography on a master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being a half ester resin of a styrene-maleic anhydride copolymer and then subjecting non-image areas other than the toner image areas to an etching treatment with a solution mainly composed of an alkali and/or an alcohol. Thus obtained printing plate is excellent in printing endurance and, besides, can be rapidly etched.
Inventors
- 👤 Shigeyoshi Suzuki
- 👤 Koji Uchida
- 👤 Jun Yamada
- 👤 Takao Senga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:26
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/26; G03G13/28; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0532; G03G5/0546
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
75 words
A method for making a printing plate which comprises forming a toner image by electrophotography on a master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being an organic solvent soluble half ester resin of a styrene-maleic anhydride copolymer and then subjecting non-image areas other than the toner image areas to an etching treatment with a solution mainly composed of an alkali and/or an alcohol.
Claim 2
Independent Claim
75 words
A method for making a printing plate which comprises forming a toner image by electrophotography on a master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being an organic solvent soluble half ester resin of a styrene-maleic anhydride copolymer and then subjecting non-image areas other than the toner image areas to an etching treatment with a solution mainly composed of an alkali and/or an alcohol.
Claim 3
Dependent Claim
26 words
A method for making a printing plate according to claim 1, wherein the half ester resin has a molecular weight of about 1,000 to about 500,000.
Claim 4
Dependent Claim
24 words
A method for making a printing plate according to claim 2, wherein the half ester resin has a molecular weight of 8,000 to 150,000.
Claim 5
Dependent Claim
27 words
A method for making a printing plate according to claim 1 wherein alcohols for obtaining the half ester resin are those of 2 to 12 carbon atoms.
Claim 6
Dependent Claim
22 words
A method for making a printing plate according to claim 1 wherein toners used for forming the toner image are wet toners.
Claim 7
Dependent Claim
25 words
A method for making a printing plate according to claim 1 wherein the etching solution is a combination of an amino alcohol and an alcohol.
Claim 8
Dependent Claim
31 words
A printing master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being a half ester resin of a styrene-maleic anhydride copolymer.
Claim 9
Dependent Claim
31 words
A printing master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being a half ester resin of a styrene-maleic anhydride copolymer.
References Cited (Backward Citations)
US3315602A
Cited
US4287293A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-24 | 1988-01-23 | 1988-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-24 | 1992-01-23 | 1992-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-24 | 1996-01-23 | 1996-07-24 | $7700.00 | Window Closed / Lapsed |