PHENOTHIAZINE AND PHENOXAZINE DERIVATIVES, PROCESS AND MARKING SYSTEMS

摘要

PHENOTHIAZINE AND PHENOXAZINE DERIVATIVESPROCESSES AND MARKING SYSTEMSABSTRACT OF THE DISCLOSURE3-(N-R2-N-Acylamino)-7-(N-R3-N-R4-amino)-10-acyl-phenothiazines and phenoxazines useful as color formers,particularly in electrochromic recording systems, are preparedby the interaction of the corresponding 3-(N-R2-amino)-7-(N-R3-N-R4-amino) phenothiazinium or phenoxazinium halide with areducing agent to obtain the corresponding leuco compound andsubsequently interacting the leuco compound with at least twomolecular proportions of an acylating agent.