our chemical factory localed in henan province , jiaozuo city , it is new factory , and we have other factory localed in wuxi, anhui, wuhan . we produce color coupler chemical materials . CAS NO. ( cas number is accurate to explain what we manufacture the techonoly person knows it well ) i will do explain if you would like know more about it . CAS RN 75805-17-3 98660-18-5 142199-90-4 36499-49-7 87563-89-1 114090-18-5 669898-40-4 v21121-62-0 22091-92-5 26567-23-7  50292-95-0 26628-47-7   CAS RN: 50293-29-3 50292-91-6 21934-68-9 565457-61-6 132467-74-4 38880-20-5 54574-00-4 21528-30-3 75805-17-3 98660-18-5 142199-90-4 My whatsapp : 0086 15639103354 , or better to my email : yuebingke@hnjydchem.com