To realize high-shear kneading in high filling of a filling material, to obtain excellent uniformity of a filler, and consequently to obtain a resin of high hardness having the high hardness and transparency, in kneading a resin and the filler.

In regard to a film of high surface hardness prepared by extrusion after the filler and the resin are melted and kneaded, a batch type kneader is used for melting and kneading in the present manufacturing method of the film.