Patent · US Expired

Carbonless duplicating systems

US4200313A · kind A · utility

3Cited by
2References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 1979
Grant dateApr 29, 1980
Priority date
Expiry dateMar 12, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S428/913
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

3-[4-(Disubstituted-amino)phenyl] or (9-julolidinyl)-3-(diphenylamino)phthalides useful as color formers in pressure-sensitive and thermal marking systems are prepared by reaction of 2-[4-(disubstituted-amino)benzoyl] or (9-julolidinyl-carbonyl)benzoic acids with diphenylamines.

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