Sulfonated Asphalt, Modified Starch, Lubricant manufacturer / supplier in China, offering Oil Drilling Chemical Auxiliary Agent Modified Starch Oil Drilling Fluid, Oil Drilling Mud Additive Shale Stabilizer / Sodium Asphalt Sulfonated / Sulphonated Aspahlt, Chemical Auxiliary Agent Modified Corn Starch for Oil Drilling Fluids Additives and so on.