Methine dyes based on formylaminopyridones

Methine dyes of the formula I ##STR62## where K is a radical of the formula ##STR63## where n is 0 or 1,

• Z.sup.1 is hydrogen, C.sub.1 -C.sub.6 -alkyl with or without interruption by 1 or 2 oxygen atoms in ether function, hydroxyl, C.sub.1 -C.sub.6 -alkoxy, C.sub.1 -C.sub.6 -alkylsulfonylamino, mono- or di(C.sub.1 -C.sub.6 -alkyl)aminosulfonylamino or the radical --NHCOZ.sup.7 or --NHCO.sub.2 Z.sup.7, wherein Z.sup.7 is phenyl, benzyl, tolyl or C.sub.1 -C.sub.6 -alkyl with or without interruption by an oxygen atom in ether function,
• Z.sup.2 is hydrogen, halogen, C.sub.1 -C.sub.6 -alkyl or C.sub.1 -C.sub.6 -alkoxy,
• Z.sup.3 and Z.sup.4 are independently of each other hydrogen, C.sub.1 -C.sub.3 -alkyl with or without substitution and with or without interruption by from 1 to 3 oxygen atoms in ether function, C.sub.3 -C.sub.4 -alkenyl , C.sub.3 -C.sub.8 -cycloalkyl, phenyl or tolyl or are together with the nitrogen atom joining them together at 5- or 6-membered saturated heterocyclic radical without further hetero atoms,
• Z.sup.5 is hydrogen or C.sub.1 -C.sub.6 -alkyl, and
• Z.sup.6 is hydrogen, halogen, C.sub.1 -C.sub.6 -alkyl, substituted or unsubstituted phenyl, substituted or unsubstituted benzyl, C.sub.3 -C.sub.8 -cycloalkyl, thienyl, hydroxyl, C.sub.1 -C.sub.6 -alkoxy, C.sub.1 -C.sub.6 -alkylthio or C.sub.1 -C.sub.6 -monoalkylamino,
• X is nitrogen, and
• Q.sup.1, Q.sup.2 and Q.sup.3 are independently of one another hydrogen, C.sub.1 -C.sub.6 -alkyl with or without interruption by 1 or 2 oxygen atoms in ether function, benzyl, C.sub.3 -C.sub.8 -cycloalkyl, substituted or unsubstituted phenyl, C.sub.1 -C.sub.4 -fluoroalkyl, C.sub.1 -C.sub.6 -alkoxy, benzyloxy, substituted or unsubstituted phenoxy, C.sub.1 -C.sub.6 -alkylthio, halogen, cyano, formylamino or a radical of the formula R.sup.3, --CO--OR.sup.1, --CO--NHR.sup.1, --CO--NH--CO--R.sup.1, --CO--NH--CO--R.sup.3, --CO--NH--SO.sub.2 --R.sup.3, --NH--CO--R.sup.1, --NH--CO--OR.sup.1, --NH--CO--NR.sup.1 R.sup.2, NH--CS--OR.sup.1, --NH-- CS--NR.sup.1 R.sup.2, --NH--CO--R.sup.3, --NH--SO.sub.2 --R.sup.1, --NH--SO.sub.2 --R.sup.3 or --NH--SO.sub.2 --NR.sup.1 R.sup.2, wherein R.sup.1 and R.sup.2 are independently of each other C.sub.1 -C.sub.13 -alkyl with or without substitution and with or without interruption by from 1 to 3 oxygen atoms in ether function, C.sub.3 -C.sub.8 -cycloalkyl or substituted or unsubstituted phenyl, or else --NR.sup.1 R.sup.2 is amino, and R.sup.3 is a 5- or 6-membered aromatic heterocyclic radical with or without benzofusion and with one or more hetero atoms selected from the group consisting of nitrogen, oxygen and sulfur,
• with the proviso that at least one of Q.sup.1, Q.sup.2 or Q.sup.3 is formylamino.