Direct Blue 295
Name:C.I.Direct Blue 295,C.I.23820
Molecular Structure: Double azo class
Molecular Formula:C34H25N6Na3O11S3
Molecular Weight: 858.76
CAS Registry Number:6420-22-0
Manufacturing Methods : 3,3′-Dimethylbenzidine double nitriding, in alkaline conditions first and 4-Amino-5-hydroxynaphthalene-2,7-disulfonic acid coupling, and then in alkaline conditions and 7-Amino-4-hydroxynaphthalene-2-sulfonic acid coupling.
Properties and Applications: blue. Soluble in water for deep purple, soluble in ethanol. The strong sulfuric acid for blue, for purple diluted. The dye solution to join strong hydrochloric acid for dark purple; Add thick sodium hydroxide solution for dark purple.
List of Suppliers:
Benzo Navy Blue BM( Bayer Group )
Direct Blue 2B-NB(Yorkshire Group pic)
Fabramine Blue 2B-NB( Fabricolor Inc. )