| abstract |
Fluoran compounds of the general formula <CHEM> wherein: R1 and R2 are each independently, lower alkyl; A is NR3R4 where R3 and R4 are each, independently, C1 to C12 alkyl, cycloalkyl, phenyl or phenyl substituted by lower alkyl or lower alkoxy; or A is a pyrrolidinyl, piperidino, morpholino or piperazino radical; are particularly suitable for use as colour formers in pressure sensitive or heat sensitive recording materials. |