| production method | with o-toluidine and phenol as raw materials, the phenol is first nitrosation, and then o-toluidine is dissolved in sulfuric acid, intermediate 3-methyl -4-amino -4 '-hydroxydiphenylamine (I) was obtained by condensation with P-nitrosophenol, and then (I) was sulfided with sodium polysulfide, oxidized, filtered, drying gives the finished product (II). One part of phenol, 1.36 part of sodium nitrite, 0.86 part of sulfuric acid and T of water were subjected to nitrosation at 12 ° C. To obtain p-nitroso phenol. 1 part of o-toluidine was dissolved in 4.3675 parts of sulfuric acid, and 1.0149 parts of p-nitroso phenol was added thereto, and the temperature was raised to 30 ° C., and condensation reaction was carried out for 1H to obtain intermediate (I). The above intermediate (I) was heated to 110-111 ° C. With 1 part of sodium sulfide, 2.75 parts of sulfur and water, and incubated for 30H for vulcanization. Then diluted with water, heated to 88-90 ° C., air oxidation for 14h, the product (sodium polysulfide sulfur content in different proportions, different vulcanization temperature, the resulting products of different colors. The proportion of sulfur content increases, the temperature rises, the color of the product is more red, and thus there are different trade names. Such as sulfide Blue BN with cyan light, sulfide blue BRN with cyan red light, sulfide blue RN with red light, etc.). |