New phthalide derivatives, process for preparing the same and recording system utilizing the same as colourless chromogenic material.

摘要

New phthalide derivatives useful as colourless chromogenic material have the general formula: <CHEM> wherein R1 is hydrogen or one to four substituents selected from the group consisting of halogen, lower alkyl, lower alkoxy, nitro and amino group represented by the general formula <CHEM> R3 is hydrogen or lower alkyl; each R3, R4, R5, R6, R8 and R9 is hydrogen, lower alkyl, benzyl, halogen substituted benzyl, phenyl, or lower alkyl or lower alkoxy substituted phenyl, or both of R3, and R4, R5 and R6 or R8 and R9 together with the adjacent nitrogen may form a cyclic polymethylene amino group represented by the general formula -N@@(CH2)a, a is an integer of 4 to 6; R7 is hydrogen or one to two substituents selected from the group consisting of halogen, lower alkyl, lower alkoxy, nitro and cyclic polymethylene amino group represented by the general formula -N@@(CH2)a, a is an integer of 4 to 6; and each X and Y is hydrogen, lower alkyl or lower alkoxy.