Patent US4957845A successfully refreshed from Google Patents.
US4957845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Printing plate
Assignee: Toray Industries Inc
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Filing: 1989-05-17
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Granted: 1990-09-18
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Expires: 2009-05-17
Abstract
Abstract The present invention is concerned with a printing plate of which image formation is done by photoirradiation, having a front side covered waith a peelable or removable protective layer which contains a photofading material. The printing plate is safe against fogging to light and can be used under ordinary illumination.
Inventors
- 👤 Masanao Isono
- 👤 Ken Kawamura
- 👤 Masaya Asano
- 👤 Tetuo Suzuki
- 👤 Shigeo Abiko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:13
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; G03F7/092
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
62 words
A silicone overlying type, dry planographic printing plate of which image formation is done by photoirradiation, said dry planographic printing plate comprising a base substrate, a photosensitive layer, an ink-repellent layer and a protective layer in that specified order, with said protective layer covering the front side of said printing plate and being removable, and said protective layer containing a photofading material.
Claim 2
Dependent Claim
62 words
A silicone overlying type, dry planographic printing plate of which image formation is done by photoirradiation, said dry planographic printing plate comprising a base substrate, a photosensitive layer, an ink-repellent layer and a protective layer in that specified order, with said protective layer covering the front side of said printing plate and being removable, and said protective layer containing a photofading material.
Claim 3
Dependent Claim
24 words
A printing plate as set forth in claim 1, wherein said photofading material has a quantum efficiency in the range of 0.01 to 1.00.
Claim 4
Dependent Claim
24 words
A printing plate as set forth in claim 1, wherein said photofading material has a quantum efficiency in the range of 0.10 to 1.00.
Claim 5
Dependent Claim
24 words
A printing plate as set forth in claim 1, wherein said photofading material has a quantum efficiency in the range of 0.20 to 1.00.
Claim 6
Dependent Claim
19 words
A printing plate as set forth in claim 1, wherein said photofading material is an aromatic diazonium salt compound.
Claim 7
Dependent Claim
28 words
A printing plate as set forth in claim 1, wherein said protective layer containing said photofading material has an optical density in the range of 0.01 to 2.00.
Claim 8
Dependent Claim
28 words
A printing plate as set forth in claim 1, wherein said protective layer containing said photofading material has an optical density in the range of 0.20 to 2.00.
Claim 9
Dependent Claim
42 words
A printing plate as set forth in claim 1, wherein said protective layer contains particles having an average particle diameter of 4 μm to 9 μm as measured by a coulter counter method and having a refractive index of 1.40 to 1.70.
Claim 10
Dependent Claim
42 words
A printing plate as set forth in claim 1, wherein said protective layer contains particles having an average particle diameter of 4 μm to 9 μm as measured by a coulter counter method and having a refractive index of 1.40 to 1.60.
Claim 11
Dependent Claim
36 words
A printing plate as set forth in claim 8 or claim 9, wherein the amount of said particles incorporated in said protective layer is in the range of 0.001 g/m 2 to 0.1 g/m 2 .
Claim 12
Dependent Claim
36 words
A printing plate as set forth in claim 8 or claim 9, wherein the amount of said particles incorporated in said protective layer is in the range of 0.01 g/m 2 to 0.1 g/m 2 .
Claim 13
Dependent Claim
25 words
A printing plate as set forth in claim 1, wherein said protective layer has a thickness in the range of 0.1 μm to 20 μm.
Claim 14
Dependent Claim
25 words
A printing plate as set forth in claim 1, wherein said protective layer has a thickness in the range of 3 μm to 20 μm.
Claim 15
Dependent Claim
21 words
A printing plate as set forth in claim 1, wherein said protective layer comprises said photofading material and a plastic film.
Claim 16
Dependent Claim
40 words
A printing plate as set forth in claim 1, wherein said protective layer is in the form of a coated film formed by coating a composition comprising said photofading material and a binder to the surface of a plastic film.
Claim 17
Dependent Claim
46 words
A printing plate as set forth in claim 1, wherein said protective layer comprises said photofading material and particles, said particles having an average particle diameter of 4 μm to 9 μm as measured by a coulter counter method and refractive index of 1.40 to 1.70.
Claim 18
Dependent Claim
69 words
A printing plate as set forth in claim 1, wherein said protective layer is in the form of a coated film formed by coating a composition to the surface of a plastic film, said composition comprising said photofading material, particles having an average particle diameter of 4 μm to 9 μm as measured by a coulter counter method and a refractive index of 1.40 to 1.70, and a binder.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-17 | 1994-03-19 | 1994-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-17 | 1998-03-19 | 1998-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-17 | 2002-03-19 | 2002-09-18 | $7700.00 | Window Closed / Lapsed |