Patent · US Expired

Direct positive image forming method comprising developing with a combination of nucleating agents

US4968592A · kind A · utility

5Cited by
8References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1988
Grant dateNov 6, 1990
Priority date
Expiry dateSep 30, 2008

Classification

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

Abstract

A direct positive image forming method comprising development processing an imagewise exposed photographic light-sensitive material comprising a support having thereon at least on photographic emulsion layer containing internal latent image type silver halide grains not having been previously fogged in the presence of a nucleating agent, wherein the nucleating agent comprises at least two kinds of nucleating agents and a ratio of nucleating rates thereof is at least 2.0. In accordance with the method of the present invention, images having both a low minimum density and an extremely high maximum density can be rapidly and stably obtained using a small amount of nucleating agents.

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