Patent · US Expired

Direct thermal imaging process with improved tone reproduction

US5527758A · kind A · utility

11Cited by
5References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1995
Grant dateJun 18, 1996
Priority date
Expiry dateMay 24, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C2200/26
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A direct thermal imaging process wherein a non-photosensitive direct thermal recording material is heated dot-wise, and said direct thermal recording material comprises an imaging layer containing uniformly distributed in a film-forming polymeric binder (i) one or more substantially light-insensitive organic silver salts, said silver salt(s) being uniformly in thermal working relationship with (ii) one or more organic reducing agents therefor, however neither including 3,5-dihydroxybenzoic acid as acidic reagent nor di-tert-butyl-p-cresol as a sole reducing agent, characterized in that said imaging layer contains at least one polycarboxylic acid and/or anhydride thereof in a molar percentage of at least 20 with respect to said silver salt(s).

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