Patent · US Expired

Photographic products and processes

US6103912A · kind A · utility

1Cited by
9References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 1993
Grant dateAug 15, 2000
Priority date
Expiry dateMar 31, 2013

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09B11/24
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A novel class of bridged indicator dyes is disclosed which possess absorption in the infrared region of the electromagnetic spectrum. These bridged indicator dyes are useful as light-absorbing, pH-sensitive optical filter agents in diffusion transfer photographic processes adapted to be performed in the presence of ambient light and to diffusion transfer products useful in such processes. These indicator dyes will also find utility in titrations and other analytical techniques and products where pH-sensitive indicator dyes are employed and absorption of infrared is useful.

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