| 摘要 |
<p>Substituted 3,6-diaminophthalides of the formula <IMAGE> wherein each of R1, R2 and R3 independently represents alkyl of not more than 12 carbon atoms which is unsubstituted or substituted by halogen, hydroxyl, cyano or lower alkoxy, or represents cycloalkyl, benzyl, or benzyl which is substituted by halogen, lower alkyl or lower alkoxy, and R1 can also be hydrogen and R3 can also be phenyl, or R1 and R2, together with the nitrogen atom to which they are attached, represent a 5- or 6-membered heterocyclic radical and the ring A is unsubstituted or substituted or contains a fused, unsubstituted or substituted benzene or heterocyclic ring. These compounds are suitable in particular for use as color formers in pressure-sensitive or heat-sensitive recording materials.</p> |
