| 摘要 |
Dye precursors of the general formula …<IMAGE>… wherein… X denotes hydroxyl, alkoxy, alkenyloxy, aralkoxy, cycloalkoxy, aryloxy, acyloxy, alkylamino, dialkylamino, acylamino, aralkylamino or arylamino,… R denotes alkyl, alkenyl or aralkyl,… R1 denotes hydrogen, halogen or alkyl,… R2 denotes alkoxy, aralkoxy, aryloxy or a radical of the formula …<IMAGE>… Y1 and Y2 independently of one another denote alkyl, aryl, cycloalkyl or aralkyl, or… R2 forms a heterocyclic ring with A in the o-position,… a benzene ring may be fused to the ring A in the o-/m-position with respect to R2, and… and the ring A and its fused-on rings and the cyclic and acyclic radicals may carry further nonionic substituents customary in dye chemistry,… are used in heat-sensitive papers and pressure-sensitive recording materials and for the production of highly concentrated solutions in organic solvents. |
