Our product PRE-GELATINIZED STARCH can be used in oil industry. Can be applied in water based drilling fluid. The product is usually kept in multi-wall bags with polythene layer inner, and the net weight of each bag is 25 kg. The product must be kept in shady, dry and ventilated warehouse. Carboxyl methyl amylum (CMS) is one kind of negative ion type macromolecular material, whose external form is white or the absorption of moisture easy to with tinyyellow solid powder, has no bad smell, may dissolve in water directly, whoseaqueous solution has the fine viscosity, stability, protect a colloid and become film, no easy rotten, invariable mildew, under basicity and weak aciditycondition, stabilize, will produce precipitayion under strong acid condition.