Direct Brown 73
Name:C.I.Direct Brown 73,C.I.35535
Molecular Structure: Multi-azo class
Molecular Formula:C45H28N20Na4O14S3
Molecular Weight: 1120.92
CAS Registry Number:
Manufacturing Methods : 4-(4-Aminophenyl)benzenamine double nitriding,first coupled with 2-Hydroxybenzoic acid, and then in alkaline conditions and 4-Amino-5-hydroxynaphthalene-2,7-disulfonic acid coupling, product to diazo, in alkaline conditions and 6-Amino-4-hydroxynaphthalene-2-sulfonic acid coupling, its product to diazo, and Benzene-1,3-diamine coupling.
Properties and Applications: red light brown. Soluble in water for brown. The strong sulfuric acid for purple brown, for yellow brown solution diluted, accompanied by precipitation. The dye solution to join strong hydrochloric acid have dark brown precipitation; Add thick sodium hydroxide solution for brown.
Standard | Acid Resistance | Alkali Resistance | Light Fastness | Soaping | Water | ||
Fading | Stain | Fading | Stain | ||||
ISO | 4-5 | 3 | 3 | 4-5 | 4 |
List of Suppliers:
Diazol Cutch BR( Francolor Pigments SA )