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:
Oct. 13, 1992
Filed:
Nov. 15, 1990
Rudolf Zertani, Mainz, DE;
Klaus Joerg, Ingelheim, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A developer concentrate is described which is used by diluting with tap water to give a read-to-use developer for negative-working exposed reproduction layers on a base. The developer concentrate is a mixture which includes water, an organic solvent, an alkali agent, an anionic surfactant, an n-alkanoic acid and/or its salts, an emulsifier, an alkali-metal salt of an oligomeric phosphate and/or of N-(2-hydroxyethyl)ethylenediaminetriacetic acid as complexing agent and also a tris(hydroxyalkyl) aminomethane as buffering substance. The developer concentrate according to the present invention exhibits, in particular, the advantage that it is stable as a concentrate, i.e., exhibits no phase separations, precipitates or turbidities, etc. . . . , and can be diluted without difficulties to produce the ready-to-use developer. The latter is also stable and exhibits optimum developer properties, in particular for reproduction layers with overcoat.