Appearance: colorless needle crystal, unstable in air, easy to turn light red
Melting point: 63-65
Boiling point: 282-284
Flash point: 175
Specific gravity (25 ° C): 1.0696
Refractive index: 1.6339
Water solubility: soluble in water (350g / L at 25), soluble in ethanol, water, chloroform, acetone, dimethylformamide, slightly soluble in ether, carbon tetrachloride, insoluble in benzene, toluene, butanol
Uses: intermediate of azo dyes and acridine dyes. It is mainly used to produce direct light resistant black RN, basic orange, basic Brown g, direct light resistant black G and other dyes. It is also used as fur dyes. In Japan, m-phenylenediamine accounts for 90% of the total consumption of azo dyes. It is also used as curing agent of epoxy resin, accelerator of cement, hair dye, mordant, color developing agent, etc.