| 摘要 |
<p>An object of the present invention is to provide a thin polymer film with a knurl having no crack and low possibility of a collapse in the height direction thereof. According to the present invention, a knurling roller (36) having protrusions (42) on a circumferential surface thereof, and a support roller (38) having a smooth circumferential surface holds and transfers a polymer film (16). The support roller (38) is closer to the downstream side of a transfer direction than a contact location between the knurling roller (36) and the polymer film (16) such that the polymer film (16) is hung and wound on the knurling roller (36). The knurling roller (36) is heated to a temperature near a melting point of the polymer film (16). The support roller (38) is maintained at 0-100°C. The polymer film (16) is heated with the protrusions (42) between the polymer film and the knurling roller, and a temperature of the heated polymer film is different from the temperature of a film surface (16a) thereof adjacent to the support roller. Surrounding protrusion parts (54), which are thick and wide, are formed at the peripheries of a knurl recess part (52) formed by the protrusion (42). The surrounding protrusion parts (54) provide a high knurl (44) having no crack and low possibility of a collapse.</p> |
