AGRICULTURAL COVERING MATERIAL

摘要

PURPOSE:To obtain an agricultural covering material which can retain a high ultraviolet screening performance over a long period of time, by blending a benzotriazole ultraviolet absorber with a mixture of linear low-density polyethylene and EVA. CONSTITUTION:80-95pts.wt. linear low-density polyethylene is blended with 20-5pts.wt. ethylene/vinyl acetate copolymer having a vinyl acetate content of 5-40wt% in such a proportion as to give a mixture having a vinyl acetate content of 0.5-5wt%. Further, a benzotriazole ultraviolet absorber is added thereto and the mixture is kneaded. The resulting resin compsn. is molded into a film of 45-105mu in thickness, thus obtaining the desired covering material. The film is an agricultural covering material which does not allow ultraviolet light having a wavelength of 370nm or below to pass therethrough. Preferred examples of the ultraviolet absorbers are compds. of formulas I and II.