Patent ID: 7812141

Claim:
A dyestuff of formula (I) wherein R 1 is C 1-2 -alkyl; allyl; propargyl; benzyl or phenyl, R 2 is H; —CH 2 CH 2 O—R 1 ; CH 2 CH 2 CN; C 1-4 -alkyl; C 2-4 -alkyl substituted by one or more substituents selected from the group consisting of: halogen, —OH, —OC 1-2 -alkyl or —OCOC 1-2 -alkyl; C 3-4 -alkenyl; substituted C 3-4 -alkenyl, propargyl; C 2-4 -alkylene-OCO—C 1-2 -alkyl; C 2-4 -alkylene-O(CO)O—C 1-2 -alkyl; C 1-2 alkylene-COO—R 5 ; C 1-2 -alkylene-COOCH 2 COOR 5 and C 1-2 -alkylene-COOCH 2 COR 6 , wherein R 5 is C 1-4 -alkyl; benzyl; C 1-2 -alkoxyethyl; C 3-4 -alkenyl; propargyl; tetrahydrofurfuryl-2; phenyl or phenyl substituted by —CH 3 , —OCH 3 , —COOCH 3 or —COOC 2 H 5 , R 6 is CH 3 or phenyl, R 3 is H or CH 3 .