| 摘要 |
<p>PURPOSE:To obtain a method having excellent economical production by thermally covering by hot rolling a nonhydrophilic plastic film at least on one side face of a hygroscopic sheet, and providing numerous fine pores at the film. CONSTITUTION:A hygroscopic sheet is coated by hot rolling with a nonhydrophilic plastic film. The film is melted at the time of hot rolling, momentarily intruded into the hygroscopic paper on the surface layer of the sheet to fusion-adhere thereto. Then, when it is pressed by a roll or a plate having numerous styluses, numerous fine pores can be easily provided at the film.</p> |
