| 摘要 |
<p>Indolyl methylene leuco dyestuffs of the formula <IMAGE> (1) wherein X1 and X2 independently of the other, represent alkyl with 2 to 12 carbon atoms, alkenyl with at most 12 carbon atoms or phenylalkyl with 1 to 4 carbon atoms in the alkyl part, Y1 and Y2 independently of the other, represent hydrogen, alkyl with 1 to 12 carbon atoms or phenyl, Z represents alkyl with 1 to 12 carbon atoms, alkenyl with at most 12 carbon atoms, aryl, aralkyl or a heterocyclic residue and the rings A and B may be further substituted by cyano, nitro, halogen, alkyl having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms or acyl with 1 to 8 carbon atoms, said methylene compounds are particularly useful as slow developing color formers in pressure-sensitive recording material and exhibit good light and air stability.</p> |
