AOX-free navy and black disperse dyes
View Patent ↗Monoazo dyestuffs of the general formula (1) wherein R 1 , R 2 , R 3 and n are as defined in claim 1, method for their preparation and a method for colouring a synthetic textile material or fiber blend thereof using such dyestuffs.
1. Monoazo dyestuff or mixture of monoazo dyestuffs of the herein below indicated and defined formula (1)
wherein
R 1 is C 1 to C 4 -alkyl
R 2 is C 1 to C 4 -alkyloxycarbonyl or cyano
R 3 is methyl or ethyl
n is 3 or 4.
2. Method for the preparation of monoazo dyestuffs according to claim 1 which comprises diazotizing dinitroaniline followed by a subsequent coupling with an aniline of formula (2):
where R 1 , R 2 , R 3 and n are as defined in claim 1 .
3. A dyestuff preparation comprising at least one dyestuff according to claim 1 and at least one dispersing agent, surfactant or wetting agent.
4. A process for coloring a synthetic textile material or fibre blend thereof, which comprises applying thereto a dyestuff or a dyestuff mixture according to claim 1 .
5. A process according to claim 4 , wherein the synthetic material or fibre blend thereof is a polyester or polyester-cellulose or polyester-wool blend.
6. Monoazo dyestuff or mixture of monoazo dyestuffs according to claim 1 ,
wherein
R 1 is ethyl or n-propyl,
R 2 is C 1 to C 2 -alkyloxycerbonyl and
n is 3.
7. Monoazo dyestuff or mixture of nionoazo dyestuffs according to claim 6 ,
wherein
R 1 is ethyl.
8. Monoazo dyestuff or mixture of monoazo dyestuffs according to claim 6 ,
wherein
R 1 is n-propyl.
9. Monoazo dyestuff or mixture of monoazo dyestuffs according to claim 1 , wherein R 2 is C 1 to C 2 -alkyloxycarbonyl.