Patent · US Expired

Silver halide photosensitive materials containing thiourea and analogue derivatives

US4749646A · kind A · utility

7Cited by
6References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 23, 1987
Grant dateJun 7, 1988
Priority date
Expiry dateMar 23, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/07
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A photographic silver halide emulsion comprising a 1,1,3,3-tetrasubstituted middle chalcogen urea compound is described wherein at least one substituent comprises an acid function. The urea compound is an effective silver halide grain growth-modifying agent. A process for modifying the grain growth of silver halide is also described.

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