US3715210A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lithographic printing plates
Assignee: EIDP Inc
•
Filing: 1971-02-19
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Granted: 1973-02-06
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Expires: 1991-02-19
Abstract
Abstract A light sensitive plate comprises a support coated with a layer comprising a tannable resin and a diazo or azido compound having light decomposition products capable of tanning the resin. The tannable resin is low viscosity hydroxyethyl cellulose or a polymer of acrylamide and at least two other monomers containing up to 30 percent by weight of the other monomers. The monomers are selected so that the layer does not swell on development. The light sensitive plate is storage stable and is suitable for the production of half-tone lithographic printing plates by the deepetch process.
Inventors
- 👤 L Watkinson
- 👤 A Service
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:28
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/016; G03F7/021; G03F7/0212
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
77 words
A presensitized light sensitive plate suitable for the production of a half-tone printing plate by the deep-etch process, which presensitized plate comprises a support coated with a layer of a light sensitive material comprising (i) a tannable resin which is a water soluble polymer containing at least 70 percent by weight of structural units derived from acrylamide and containing structural units derived from acrylonitrile or pound having light decomposition products which are capable of tanning the resin.
Claim 2
Dependent Claim
77 words
A presensitized light sensitive plate suitable for the production of a half-tone printing plate by the deep-etch process, which presensitized plate comprises a support coated with a layer of a light sensitive material comprising (i) a tannable resin which is a water soluble polymer containing at least 70 percent by weight of structural units derived from acrylamide and containing structural units derived from acrylonitrile or pound having light decomposition products which are capable of tanning the resin.
Claim 3
Dependent Claim
46 words
A presensitized light sensitive plate as claimed in claim 1, wherein said polymer contains up to 20 percent by weight of structural units derived from acrylic acid and wherein the structural units derived from acrylonitrile constitute from 10 to 20 percent by weight of the polymer.
Claim 4
Dependent Claim
28 words
A presensitized light sensitive plate as claimed in claim 2, wherein the structural units derived from acrylonitrile constitute from 13 to 15 percent by weight of the polymer.
Claim 5
Dependent Claim
42 words
A presensitized light sensitive plate as claimed in claim 1, wherein the diazo compound is 4-diazo-diphenylamine sulphate, the condensation product of 4-diazodiphenylamine sulphate and paraformaldehyde in sulphuric acid, or the zinc chloride salt of the condensation product of 4-diazo diphenylamine and paraformaldehyde.
Claim 6
Dependent Claim
29 words
A presensitized light sensitive plate as claimed in claim 1, wherein the azido compound is 4,4''-diazidostilbene-2,2''-disulphonic acid, a 4-azido-benzal-mesityl oxide 2-sulphonic acid salt, or a 4-azido-benzal-acetone 2-sulphonic acid salt.
Claim 7
Dependent Claim
33 words
A presensitized light sensitive plate as claimed in claim 1, wherein a substance having a strong absorption spectra in the 2, 700 to 4,000 Angstrom region is included in the light sensitive layer.
Claim 8
Dependent Claim
24 words
A presensitized light sensitive plate as claimed in claim 6, wherein said substance is selected from the group consisting of auramine, chrysoidine and tartrazine.
References Cited (Backward Citations)
US2246425A
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US2687958A
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US2692826A
Cited
US2702243A
Cited
US3287128A
Cited
US3479182A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |