RECORDING MEDIUM FOR OPTICAL DATA STORAGE

摘要

An optical recording element on which information can be recorded and read directly afterwards by means of laser light in which the element comprises, as a recording medium, an effective amount of one or more dyes of the formula: (I) in which: m+p=2, n is 0 or 1, s is 0 or 1, Z1 and Z2 independently represent the non-metallic atoms necessary to complete a heterocyclic nucleus of the type present in cyanine dyes, R1 and R2 independently represent an alkyl or substituted alkyl, alkenyl, substituted alkenyl or aralkyl group of up to 20 carbon atoms, R3 and R4 independently represent a hydrogen atom or an alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkoxy or substituted alkoxy group of up to 10 carbon atoms, R5, R6, R7 and R8, which together may not contain more than 12 carbon atoms, independently represent a hydrogen atom, an alkyl, substituted alkyl, alkenyl, substituted alkenyl, aryl or alkaryl group, or one of R5 and R6 together with one of R7 and R8 represent the necessary atoms to complete a carbocyclic ring in which case the others of R5 to R8 are absent, Q1 and Q2 together represent the non-metallic atoms necessary to complete an acidic nucleus of the type present in oxonol or merocyanine dyes.