Azulenemethine dyes and an optical recording medium containing the novel dyes

摘要

An optical recording medium contains novel azulenemethine dyes of the formula where R is unsubstituted or substituted C1-C6-alkyl, X(-) is an anion, A(+) is heterocyclic radical, of the formula (IIa) (IIb) (IIc) (IId) (IIe) (IIf) (IIg) (IIh) (IIi) (IIj) or (IIk) wherein R1, R2, R3, Y, Z and W are as defined, with the proviso that, when A(+) is a radical of the formula II f, II g, II i or II k, m is 2, A is 1, 2 or 3 and M is 1 or 2.