PURPOSE: To manufacture the product of high molecular weight material efficiently by a method in which primary drawing is carried out by rolling, and then in the drawing in another direction, the material is nipped under pressure between the rolls kept at a prescribed temperature and is drawn, by constraining the leading end of said material.
CONSTITUTION: To obtain the high molecular weight material having equal strength in biaxial directions, the value of second drawn ratio may be less than that of first draw ratio. That is, as the drawing method to keep the first draw ratio in 5, conventional rolling method has high productivity and is most suitable, but for the drawing achieved successively in the direction perpendicular thereto, rolling is not entirely suitable, since the length of said material is different. Then, a pair of rolls are set and the material 2 is nipped under pressure by said rolls, and if the leading end of said material is drawn by a drawing device 3, the value 2 of sufficiently maximum draw ratio may be obtained, whereby its equipment becomes compact. The resin material may be drawn in a stable shape by the tension in front direction, and the defects of wavy shapes such as the defects occurring in rolling do not occur.
HIGASHIDA YASUHIRO
WADA YASUHIRO
KIKUMA TOSHIO
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