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US4606985A Expired / Lapsed US ⏱️ 0.0 years remaining

Lithographic printing plates

Assignee: Mitsubishi Paper Mills Ltd
•
Filing: 1982-08-27
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Granted: 1986-08-19
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Expires: 2002-08-27
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Abstract

Abstract Lithographic printing plates which have on a support at least one hardened gelatin-containing layer which contains a photographic gelatin and a low molecular-weight gelatin are improved in printing endurance, e.g., resistances against ink-staining and blinding of image areas.

Inventors

  • 👤 Yoshikazu Takaya
  • 👤 Yasuo Tsubai
  • 👤 Hiroshi Nishinoiri

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 19:53
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/06; G03F7/07

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 117 words
A lithographic printing plate which uses silver or silver halide image as ink receptive area and which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to about 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layer containing the photographic gelatin and the low molecular weight gelatin being hardened.
Claim 2
Dependent Claim 117 words
A lithographic printing plate which uses silver or silver halide image as ink receptive area and which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to about 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layer containing the photographic gelatin and the low molecular weight gelatin being hardened.
Claim 3
Dependent Claim 57 words
A lithographic printing plate according to claim 1 containing an undercoating layer, a silver halide emulsion layer, an intermediate layer and a physical development nuclei layer and wherein the gelatin-containing layer containing the photographic gelatin and the low molecular-weight gelatin is one of the undercoating layer, silver halide emulsion layer, intermediate layer, and physical development nuclei layer.
Claim 4
Dependent Claim 30 words
A lithographic printing plate according to claim 1 containing an undercoating layer and wherein the gelatin-containing layer containing the photographic gelatin and the low molecular-weight gelatin is the undercoating layer.
Claim 5
Dependent Claim 16 words
A lithographic printing plate according to claim 3, wherein the photographic gelatin is an acid-treated gelatin.
Claim 6
Dependent Claim 17 words
A lithographic printing plate according to claim 1 which is made by silver complex diffusion transfer process.
Claim 7
Dependent Claim 17 words
A lithographic printing plate according to claim 1, wherein the gelatin-containing layer is hardened with aldehyde hardeners.
Claim 8
Independent Claim 122 words
A method for making a lithographic printing plate which comprises imagewise exposing a photosensitive material which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to about 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layers containing the photographic gelatin and the low molecular weight gelatin being hardened and then developing thus exposed material.
Claim 9
Independent Claim 122 words
A method for making a lithographic printing plate which comprises imagewise exposing a photosensitive material which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to about 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layers containing the photographic gelatin and the low molecular weight gelatin being hardened and then developing thus exposed material.
Claim 10
Independent Claim 142 words
A method for printing with a lithographic printing plate which uses silver or silver halide image as ink receptive area and which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layer containing the photographic gelatin and the low molecular weight being hardened, said process comprising applying a fountain solution to said lithographic printing plate, inking said printing plate and printing with said printing plate.
Claim 11
Independent Claim 142 words
A method for printing with a lithographic printing plate which uses silver or silver halide image as ink receptive area and which has at least one hardened gelatin-containing layer on a support, wherein at least one of the gelatin-containing layers contains a composition including a gelatin resulting from mixing a photographic gelatin having an average molecular weight of about 70,000 to 150,000 and a low molecular weight gelatin having an average molecular weight of about 3,000 to about 30,000, said low molecular weight gelatin being contained in an amount of about 3 to 30 parts by weight for 100 parts by weight of the photographic gelatin and said layer containing the photographic gelatin and the low molecular weight being hardened, said process comprising applying a fountain solution to said lithographic printing plate, inking said printing plate and printing with said printing plate.

References Cited (Backward Citations)

US3454398A Cited
US3721559A Cited
US3764323A Cited
US4230792A Cited
US4360590A Cited
US4361639A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-08-18 1990-02-17 1990-08-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-08-18 1994-02-17 1994-08-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-08-18 1998-02-17 1998-08-19 $7700.00 Window Closed / Lapsed

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