Patent · US Expired

Method for forming a direct positive image from a material comprising a nucleation accelerator

US5037726A · kind A · utility

47Cited by
17References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 7, 1988
Grant dateAug 6, 1991
Priority date
Expiry dateDec 7, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/141
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method for forming a direct positive image having a high Dmax and a low Dmin, which comprises image-wise exposing a photographic light-sensitive material having on a support at least one photographic emulsion layer containing unprefogged internal latent image-type silver halide grains and developing the photographic light-sensitive material after or while fogging to form direct positive image, wherein the aforesaid development is performed in the existence of at least one compound selected from the group consisting of compounds represented by formula (I), (II), (III), (IV), (V) or (VI), acid salts of compounds represented by formula (I) to (IV) provided substituents thereof contain an amino group, and acid salts of compound represented by formula (V) or (VI); ##STR1## wherein symbols are defined as in claim 1.

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