Tri- or tetrasubstituted diphenylphthalides
US4094877A · kind A · utility
6Cited by
1References
52Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1976 |
| Grant date | Jun 13, 1978 |
| Priority date | — |
| Expiry date | Nov 10, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/327
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Substituted 3,3-diphenylphthalides, useful as color precursors, particularly in the art of pressure-sensitive duplicating systems and heat-sensitive marking systems, are prepared by condensing substituted 2-benzoylbenzoic acids with substituted anilines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.