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Process for the production of lithographic printing plates and light-sensitive materials for use therein

Assignee: Fujifilm Holdings Corp
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Filing: 1981-11-26
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Granted: —
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Expires: 2001-11-26
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Abstract

Abstract A process for the production of lithographic printing plates, and a light-sensitive material for use in the process are described. The light-sensitive material comprises an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, wherein the positive type light-sensitive layer and the photoconductive insulative layer are provided on the support as a unit layer or individually in that order, and the photoconductive insulative layer can be charged either positively or negatively. The desired lithographic printing plate can be prepared by treating the light-sensitive material by the simple process of the invention.

Inventors

  • 👤 Takashi Kitamura
  • 👤 Hiroshi Kokado

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 14:10
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/20; G03F7/2002; G03F7/2014; G03F7/2016; G03F7/2018; G03F7/004; G03F7/09; G03F7/105; G03G; G03G13/00; G03G13/26; G03G5/00; G03G5/153; Y; Y10; Y10S; Y10S430/00; Y10S430/141

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 173 words
A process for producing a lithographic printing plate using a light-sensitive material comprising an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, said process comprising the steps of: (A) forming an electrophotographic latent image on the photoconductive layer of the light-sensitive material; (B) developing the latent image with a liquid developer containing developer particles which are opaque to light having a wavelength to which the positive type light-sensitive layer is sensitive; (C) exposing to light the positive type light-sensitive layer through the developed image obtained in step (B); and (D) selectively removing the areas of the positive type light-sensitive layer not bearing the developed image; wherein: the positive type light-sensitive layer and the photoconductive insulative layer are provided on the support as a unit layer, or are individually provided in that order; and the photoconductive insulative layer is substantially chargable either positively or negatively, and does not inhibit the selective removal of the positive type light-sensitive layer in step (D).
Claim 2
Dependent Claim 173 words
A process for producing a lithographic printing plate using a light-sensitive material comprising an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, said process comprising the steps of: (A) forming an electrophotographic latent image on the photoconductive layer of the light-sensitive material; (B) developing the latent image with a liquid developer containing developer particles which are opaque to light having a wavelength to which the positive type light-sensitive layer is sensitive; (C) exposing to light the positive type light-sensitive layer through the developed image obtained in step (B); and (D) selectively removing the areas of the positive type light-sensitive layer not bearing the developed image; wherein: the positive type light-sensitive layer and the photoconductive insulative layer are provided on the support as a unit layer, or are individually provided in that order; and the photoconductive insulative layer is substantially chargable either positively or negatively, and does not inhibit the selective removal of the positive type light-sensitive layer in step (D).
Claim 3
Dependent Claim 81 words
A light-sensitive material comprising an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, wherein: the positive type light-sensitive layer and the photoconductive insulative layer are provided on the .support as a unit layer or individually in that order; and the photoconductive insulative layer is substantially chargable either positively or negatively, and does not inhibit selective removal of areas of the positive type light-sensitive layer having a developed image.
Claim 4
Dependent Claim 81 words
A light-sensitive material comprising an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, wherein: the positive type light-sensitive layer and the photoconductive insulative layer are provided on the .support as a unit layer or individually in that order; and the photoconductive insulative layer is substantially chargable either positively or negatively, and does not inhibit selective removal of areas of the positive type light-sensitive layer having a developed image.
Claim 5
Dependent Claim 24 words
A light-sensitive material as in Claim 2, further having an intermediate layer provided between the photoconductive insulative layer and the positive type light-sensitive layer.

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