| abstract |
Fluorescent dyestuffs of the formula <IMAGE> (I) wherein: R1 and R2 independently of one another represent hydrogen, a salt-forming cation, an alkyl radical with 1 to 8 carbon atoms or an aralkyl radical which is optionally substituted by non-chromophoric groups, R2 to R5 independently of one another represent hydrogen, alkyl, trifluoromethyl, alkoxy, aralkoxy, alkenyloxy, halogen or the carboxyl, cyano, alkylsulphonyl, arylsulphonyl, carboxamide or sulphonamide group or a carboxylic acid ester group, m and n independently of one another denote 0, 1 or 2 and the sum of m+n must be at least 2, and o, p, q and r independently of one another represent 0, 1 or 2. |