Patent · US Expired

Dry silver systems with fluoran leuco dyes

US5185231A · kind A · utility

6Cited by
22References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 26, 1991
Grant dateFeb 9, 1993
Priority date
Expiry dateAug 26, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/49854
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Certain fluoran dyes have been found to be effective reducing agents for silver ion in dry silver constructions. The fluoran dyes have the following structure: ##STR1## wherein: R.sup.1 represents methyl or n-butyl; PA0 R.sup.2 represents n-butyl or cyclohexyl; PA0 R.sup.3 represents hydrogen, methyl, or methoxy; and PA0 R.sup.4 represents ##STR2## where X represents halogen (preferably chlorine); and a binder.

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