p-Methylaniline (2 Moore) and sulfur (4.5 atomic ratio) in 200 ~ 280 ℃ heat, with hair smoke from the sulphonated sulfuric acid alkali primrose spirit. The product C.I. Direct Yellow 59 (C.I. 49000) diazo, coupled with the 4-Hydroxynaphthalene-1-sulfonic acid.