Hangzhou Haichem Co., Ltd'main products involved into hair dyes, special intermediates and active pharmaceutical ingredients like derivatives of pyridine, pyrazole, and indole. As a leading manufacturer, we have two production bases and one R&D center with experienced chemists. Haichem does contract manufacturing from kilograms to tons by handling hydrogenation, chlorination, ethoxylation, acetylation, alkylation, amination (substitution), diazotization, nitration, nitrosation, cyclization, ...