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US4957845A Expired / Lapsed US ⏱️ 0.0 years remaining

Printing plate

Assignee: Toray Industries Inc
•
Filing: 1989-05-17
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Granted: 1990-09-18
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Expires: 2009-05-17
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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 09:31
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)

US2702243A Cited
US3933499A Cited
JPS5555343A Cited
EP0130222A1 Cited
US4804614A Cited

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

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