CHROMENOAZAINDOLIZINES, PROCESS FOR THEIR PREPARATION AND THEIR USE IN PRESSURE OR HEAT SENSITIVE RECORDING MATERIALS

摘要

The invention relates to chromenoazaindolizines of the general formula (1a) (1b) wherein each of Y, X1 and X2 independently of the other is hydrogen, halogen, lower alkyl, lower alkanoylamino or a group of the formula OR3or (1c) (1d) each of R1, R2, R3 and R4 independently of the other is hydrogen, C1-C12 alkyl which is unsubstituted or substituted by halogen, hydroxy, cyano or lower alkoxy, or is cycloalkyl, phenyl, benzyl, or phenyl or benzyl each substituted by halogen, nitro, lower alkyl or lower alkoxy, or each pair of substituents (R1 and R2) and (R3 and R4) independently of the other, together with the nitrogen atom to which said pair is attached, is a 5- or 6-membered heterocyclic radical; and each of the rings A and B independently of the other is unsubstituted or substituted by halogen, nitro, lower alkyl, lower alkoxy, phenyl, phenoxy, or by an amino group which is unsubstituted or mono- or di-substituted by lower alkyl, phenyl, lower alkanoyl or benzyl. These compounds are particularly suitable for use as color formers in pressure-sensitive or heat-sensitive recording materials and produce lightfast blue, greenish-blue or green colorations.