3-(Pyrrolo and 3-indolyl)-3-diphenylamino substituted phthalides
US4431819A · kind A · utility
4Cited by
3References
31Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1980 |
| Grant date | Feb 14, 1984 |
| Priority date | — |
| Expiry date | Apr 28, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/145
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
3-Heteroaryl-3-(diphenylamino)phthalides useful as color formers in pressure-sensitive carbonless duplicating systems, thermal marking systems and hectographic copying systems are prepared by reacting 2-(heteroarylcarbonyl)benzoic acids with diphenylamines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.