Patent · US Expired

Two-component diazotype material with ultraviolet light-absorbing dye salt of a benzothiazole

US4540648A · kind A · utility

20Cited by
6References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 28, 1984
Grant dateSep 10, 1985
Priority date
Expiry dateFeb 28, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/61
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The present invention relates to a two-component diazotype material comprising a support and one or several light-sensitive layers, each of which contains at least one light-sensitive diazonium salt, a coupler component and an acid stabilizer, and at least one of the layers contains a compound which absorbs light in the ultraviolet spectral region. The light-absorbing compound is present in the form of a dye salt of at least one benzothiazole which is converted into its leuco base under the action of an alkaline medium. It thus partially or completely loses its absorptivity toward radiation in the long-wave ultraviolet and short-wave visible spectral regions. The light-absorbing compound comprises a benzothiazole, in particular according to the general formula: ##STR1## wherein R.sub.1 denotes hydrogen, alkyl or aralkyl, PA0 R.sub.2 denotes hydrogen or an optionally substituted alkyl, aralkyl, aryl, pyridylalkyl, carbalkyl, carboxyalkyl, carboxyaryl, carbamoyl, or sulfamoyl radical, or PA0 R.sub.1 and R.sub.2 denote members of a heterocyclic radical, and PA0 R.sub.3 denotes hydrogen or alkyl.

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