Founded in 1985, Tianjin greatwall youxing chemical Co.,Ltd. mainly manufactures orgnic dyes and related intermediates. We have collaborative relationships with some top research institutes and academic organizations to backup our research and development activities. Our main products are Dehydrothio-p-toluidine monosulfonic acid and Dehydrothio-p-toluidine disulfonic acid - fast-resistant dyes well requested by the world market. We utilize Dionex HPLC in manufacturing process and quality control. Today, we are a competitive medium-sized enterprise.