At present, the common domestic varieties of smooth agent amide (oleic acid amide and erucic acid amide), soap (calcium stearate, etc.) and silicone (silicone) three categories. The latter is liquid, inconvenient to add and use, expensive and difficult to popularize. Although soap products are cheap, but the effect is not ideal, and the amount of addition is large, in the middle and high-grade products basically cannot be used. Oleic acid amide and erucic acid amide, the price is moderate, the effect is obvious, the addition amount is very little (0.05% ~ 0.3%), non-toxic (FDA certification), the use of a wide range. Therefore, it has a wide prospect of popularization and application.