Mesolonic compounds in the preparation of lithographic printing plate by diffusion transfer
AssigneeFuji Photo Film Co., Ltd.
InventorKatsumi Hayashi
Life of this patent
Estimating the term…
Abstract
A lithographic printing plate is prepared from a silver halide photosensitive material in accordance with a silver complex diffusion transfer process. The photosensitive material is exposed and developed with a diffusion transfer processing solution containing a mesoionic compound as a silver halide complexing agent. The printing plate has good ink receptivity and minimized plate wear. The processing solution is free from the problems of corrosion and waste solution disposal.
Claims14
A method for preparing a lithographic printing plate from a photosensitive material, wherein said photosensitive material comprises at least a silver halide emulsion layer and a physical development nucleus layer on a support, comprising the steps of:
- (a) imagewise exposing said photosensitive material;
- (b) developing the resulting photosensitive material with a diffusion transfer processing solution, comprising at least one mesoionic compound;
- and
- (c) processing the resulting photosensitive material with a neutralizing solution, thereby obtaining said lithographic printing plate,
- wherein said mesoionic compound is represented by formula (2):
- ##STR4## wherein R.sub.1 and R.sub.2 are independently selected from the group consisting of an alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, aryl and heterocyclic radical, R.sub.2 may also be a hydrogen atom,
- Y is --N(R.sub.3)--, wherein R.sub.3 is selected from the group consisting of an alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, aryl, heterocyclic, amino, acylamino, sulfonamide, ureido, and sulfamoylamino, and
- R.sub.1 and R.sub.2, and R.sub.2 and R.sub.3 taken together may form a ring.
Dependencies are inferred from the claim text.