Direct Red 37
Name:C.I.Direct Red 37,C.I.22240
Molecular Structure: Double azo class
C.I.Direct Red 37,C.I.22240,CAS 3530-19-6,676.63,C30H22N4Na2O8S2,Direct Scarlet B New,Direct Scarlet B
Molecular Formula:C30H22N4Na2O8S2
Molecular Weight: 676.63
CAS Registry Number:3530-19-6
Manufacturing Methods : 4-(4-Aminophenyl)benzenamine double nitriding, first and 7-Hydroxynaphthalene-1,3-disulfonic acid coupling, again with phenol coupling, and then in contain sodium carbonate in aqueous solution of ethanol heating, air pressure,Using Chloroethane to make phenol hydroxy ethylated .
Properties and Applications: red. Soluble in water for red, slightly soluble in alcohol, acetone and soluble fiber element, insoluble in other organic solvents. The strong sulfuric acid for dark purple, after diluted brown precipitation; In nitric acid solution for colourful red. The dye solution to join strong hydrochloric acid have orange brown precipitation; Add thick sodium hydroxide solution for red orange, precipitation.
| Standard | Acid Resistance | Alkali Resistance | Light Fastness | Soaping | Water | ||
| Fading | Stain | Fading | Stain | ||||
| ISO | 3-4 | 4 | 2 | 1-2 | 1-2 | ||
| AATCC | 3 | 5 | 2-3 | 1 | 1 | ||
List of Suppliers:
Apollo Direct Scarlet B New( Taiheung Corp )
Shikiso Direct Scarlet B( Kaseihin Kogyo Kyokai )