Fluoran derivatives as new compounds and recording system utilizing the same as colorless chromogenic material
US4536220A · kind A · utility
12Cited by
1References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1983 |
| Grant date | Aug 20, 1985 |
| Priority date | — |
| Expiry date | Dec 19, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D493/10
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A new fluoran derivative useful as a colorless chromogenic material has the following formula: ##STR1## wherein R, R.sub.1, R.sub.2, R.sub.3, X and Y have the same meaning as defined hereinbefore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.