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.

Date of Patent:
Mar. 03, 1981

Filed:

Mar. 26, 1979
Applicant:
Inventors:

Ekkehard Kramp, Marly, CH;

John Lenoir, Marly, CH;

Max Marthaler, Marly, CH;

Assignee:

Ciba-Geigy AG, Basel, CH;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03C / ; G03C / ;
U.S. Cl.
CPC ...
430419 ; 430456 ; 430488 ;
Abstract

A process is described for the prevention of darkening and the formation of a sediment in photographic developer solutions which contain a silver halide developer, a water-soluble silver halide solvent and organic sulfur compounds. The organic sulfur compounds are a combination of (a) an organic thiol compound or thione compound capable of tautomerism and (b) a Bunte salt which contains groups conferring solubility in water. Developer solutions which contain the indicated combination of sulfur compounds are outstandingly stable.


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