Polyethylene plastic film has been widely used in agricultural production, but because it can not be degraded that has become the “white pollution”, so is an urgent need to slove the problem.

Lignin is a natural soluble polymers, add a small amount of alkali namely into membranous, also has a certain strength. if add a small amount of formaldehyde in the lignin solution as crosslinking agent, increasing the relative molecular mass, to increase its strength and membranous, add a small amount of short fiber or other soluble polymer, to further increase its strength and film-forming, also add some surfactants and foams, the liquid mixture thus prepared is sprayed onto the soil surface with a sprayer, to form a thick layer of foam, the soil surface forming a uniform layer of mulch after defoaming.

The advantage of this film is forming in the soil surface, reduce the labor intensity, when crop seedlings grow can bursting, don’t need artificial rupture of membranes.

It will gradually become the degradation of humic acid fertilizer, And can improve soil aggregate structure, Cover before degradation in soil surface to prevent moisture evaporation, prevent weeds. Due to the lignin has antiseptic effect, and has the ability to absorb ultraviolet light, Can improve the ground temperature, aslo can help crop to improve the disease resistance. This film may also join the pesticide and fertilizer, Become a multi-functional composite membrane, Its cost is lower than various synthetic film.