The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1981
Filed:
Apr. 30, 1980
Kotaro Yamasue, Shizuoka, JP;
Hiroshi Takahashi, Shizuoka, JP;
Hirokazu Sakaki, Shizuoka, JP;
Akira Nishioka, Shizuoka, JP;
Fuji Photo Film Co., Ltd., Ashigara, JP;
Abstract
A development method which comprises imagewise exposing a positive acting light-sensitive planographic printing plate comprising an aluminum support and a light-sensitive layer of an o-quinonediazide compound formed thereon, and then developing the exposed plate with a developer, comprising an aqueous solution of an alkali metal silicate, adding a supplementary solution comprising an aqueous solution of an alkali metal silicate to the developer to compensate for the degradation of the developer brought about by development and/or by carbon dioxide in the air; wherein the developer comprises an aqueous solution of an alkali metal salt having an [SiO.sub.2 ]/[M] ratio of from 0.5 to 0.75 and an SiO.sub.2 concentration of from 1 to 4% by weight based on the total weight of the developer, where [SiO.sub.2 ] represents the concentration of SiO.sub.2 per unit volume expressed as gram-molecules, and [M] represents the concentration of the alkali metal per unit volume expressed as gram-atoms, and the supplementary solution comprises an aqueous solution of an alkali metal silicate having an [SiO.sub.2 ]/[M] ratio of from 0.25 to 0.75.