Dispersion dyes of naphthalimide series - for synthetic fibres, esp. polyesters and thermoplastics

Naphthalimide dispersion dyes of formula (I): (in which R is opt. substd. alkyl, cycloalkyl, aralkyl or heteroalkyl; R2 is H or opt. substd. alkyl or aralkyl; R1 is as R2, or opt, substd. cycloalkyl, aryl or heteroaryl; R1 and R2 together with the N atom may form a 5-7 member ring; R3 is H, alkoxy or beta-alkoxy-alkoxy with 1-4C alkoxy gps., Cl, Br or NR1R2) are for dyeing or printing cellulose esters, polyamides and esp. polyesters, as well as acrylonitrile, polymers contg. basic gps. (I) are useful for mass colouring of thermoplastics, giving yellow to greenish-yellow fluorescent shades. (I) give strong shades with good fastness, esp. to thermofixing, exhaust gas and washing.