| abstract |
Use as pigment dyes of cpds. of formula:- (in which R1 is a nitrile gp., a -COOR3 or -COR3 gp., R3 is 1-3 C alkyl, R2 is a carbonamide gp., which is opt. N-substd. with 1-3 C alkyl or aryl or heterocyclic gp., of the gp. is a 4,6-dioxotetrahydropyridine or a 2,4-dioxo-1,2,3,4-tetrahydroquinoline gp.). The dyes, purer and obtd. in better yield than by known processes, are suitable as pigments for thermoplastics, paints and inks. |