Dihydroindoles and indolenine dyestuffs

Methine dyestuff of the formula ##SPC37##

• in which
• R.sub.1 and R.sub.2 are C.sub.1 --C.sub.4 -alkyl;
• R.sub.3 is hydrogen, a non-ionic substituent, carboxyl, or together with the ring, to which it is attached, a benzene ring;
• n is 1, 2, 3 or 4;
• R.sub.4 and R.sub.5 are hydrogen or a non-ionic substituent;
• X.sup.(.sup.-) is an anion;
• said non-ionic substituents selected from the group consisting of C.sub.1 --C.sub.9 alkyl, chloromethyl, C.sub.1 --C.sub.12 -alkoxymethyl, phenoxymethyl, p-nitrophenoxymethyl, p-methoxyphenoxy, p-chlorophenoxymethyl, allyloxymethyl, propargyloxymethyl, hydroxymethyl, di-C.sub.1 --C.sub.4 -alkylaminomethyl, diallylaminomethyl, pyrrolidinomethyl, phthalimidomethyl, allyl, trifluoromethyl, phenyl, benzyl, cyclohexyl, C.sub.1 --C.sub.4 -alkoxy, sulfamoyl, CN, carbomethoxy, carboethoxy, fluorine, chlorine, methylmercapto, methylsulfonyl and acetylamino;
• B.sub.1 is CH -- Ar.sub.1 or ##EQU8## Z together with C and N to which it is attached, forms an indolinyl-2-ring;
• Ar.sub.1 is a radical of the p-amino-benzene, naphthalene;
• benzofurane, benzothiophene, indole, indoline, 1,2,3,4-tetrahydroquinoline, carbazole, quinoxaline, dihydro-[benzo-1,4-oxazine], dihydro-[benzo-1,4-thiazine], 9, 10-dihydro-phenazine, phenoxazine or phenthiazine series;
• R.sub.6 is methyl, ethyl or benzyl.