Patent · US Expired

Method for bleaching color photosensitive material

US4508816A · kind A · utility

10Cited by
2References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 21, 1983
Grant dateApr 2, 1985
Priority date
Expiry dateOct 21, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C7/421
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

An improved method for bleaching color photosensitive materials with a persulfate is provided. This method is free of offensive odors, can bleach efficiently color photosensitive materials containing a large amount of silver by using a persulfate, and can effectively bleach color photosensitive materials having colloidal silver layers by using a persulfate. The color photosensitive material used in the present invention contains at least one of the compounds represented by the formula I, salts thereof and precursors thereof: ##STR1## where R.sup.1 and R.sup.2 each independently represents a hydrogen atom, or an aliphatic residue and R.sup.1 and R.sup.2 may form a ring together with the N atom; R.sup.3 represents --R.sup.4 -- or --R.sup.4 --S, said --R.sup.4 -- being a divalent aliphatic residue; and X represents a divalent heterocyclic ring residue containing at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.