Naphtholactam dyes and optical recording medium containing these dyes

An optical recording medium consisting of a base and a laser-sensitive, dye-containing layer of a polymer, said polymer being selected from thermoplastics or crosslinked plastics wherein the polymer contains one of more naptholactam dyes of the formula Ib ##STR35## where R.sup.1 and R.sup.3 are identical or different and independently of one another are each C.sub.4 -C.sub.20 -alkyl which may be interrupted by ether oxygen or each are benzyl,2-phenylethyl or C.sub.5 or C.sub.6 -cycloalkyl

• R.sup.2, R.sup.4 and R.sup.5 are identical or different and independently of one another are each hydrogen, C.sub.1 -C.sub.4 -alkyl, C.sub.5 -C.sub.6 -cycloalkyl, phenyl, alkoxycarbonyl in which alkoxy is C.sub.1 -C.sub.4, carboxyalkyl in which alkyl is methyl or ethyl, hydroxyl, chlorine or bromine,
• n is 0 or 1,
• p, independently of n, is 0, 1 or 2,
• Z.sup.1 and Z.sup.2 are each hydrogen or, where n is 1, may together form an unsubstituted or C.sub.1 -C.sub.4 -alkyl-substituted C.sub.2 - or C.sub.3 -alkylene chain or together with the moiety to which they are attached from the radical ##STR36## and X- is an anion, and
• the rings A, B, C and D are unsubstituted or substituted by methyl, ethyl, phenyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.6 -alkylthio, cyano, dialkylamine in which each alkyl is methyl or ethyl, chlorine, bromine, hydroxysulfonyl, phenylthio or the radical, ##STR37## with the proviso that if (a) at least one of the rings A, B, C, or D are unsubstituted or substituted by chlorine, bromine, C.sub.1 -C.sub.4 -alkoxy, dialkylamino in which each alkyl is methyl or ethyl, n and p are not simultaneously 0,
• (b) at least one of the rings A, B, C or D are unsubstituted or substituted by chlorine, bromine, C.sub.1 -C.sub.4 -alkoxy, dialkylamino in which each alkyl is methyl or ethyl, n is 1, p is 0 and Z.sup.1 and Z.sup.2 are each hydrogen R.sup.2 is not hydrogen,
• (c) at least one of the rings A, B, C or D are unsubstituted or substituted by chlorine, bromine, C.sub.1 -C.sub.4 -alkoxy, dialkylamino in which each alkyl is methyl or ethyl, n is 0 and p is 1 or 2, R.sup.4 and R.sup.5 are not simultaneously hydrogen, and
• (d) at least one of rings A, B, C or D are unsubstituted or substituted by chlorine, bromine, C.sub.1 -C.sub.4 -alkoxy, dialkylamino in which each alkyl is methyl or ethyl, n and p are each 1 and Z.sup.1 and Z.sup.2 are each hydrogen, one or more of the radicals R.sup.2, R.sup.4 and R.sup.5 is not hydrogen.