New cyclic amino xanthene dyes - esp. for producing black shades in thermal printing paper

摘要

Xanthene derivs. of formula (I) are new. In (I) R1 = a N-bonded 5- or 7-membered satd. heterocyclic gp. substd. by one to four 1-4C alkyl gps. USE - (I) are useful as dyes for producing black shades, esp. in thermal printing paper.