| 摘要 |
PURPOSE:To easily roughen a synthetic resin sheet surface by passing a heated synthetic resin sheet through a clearance between a pair of rotating rolls wherein outer surface of the lower roll is covered with thereto sticking inorganic chips, transferring the chips to the surface of the sheet to bury therein and removing the chips from the sheet by the aid of a roll with brush. CONSTITUTION:Preheated synthetic resin sheet 1' is passed through a clearance between an upper roll 2 having a smooth outer surface and a lower roll 3 with outer surface carrying adsorbed chip 5 of inorganic substances like calcium carbonate, quartz sand, etc. which are made sticky and contained in a bucket 4. The inorganic ships 5 are thus transferred to the synthetic resin sheet 1' and buried therein and cooled. Then, the inorganic chips 5 sticking to the synthetic resin sheet 1' are removed by the aid of a roll 6 provided with a brush so that hollow parts a are formed. In this way, a synthetic resin sheet 1 having hollow parts a and projected parts b on its one side is continuously obtained. The inorganic chips 5 are recovered and reused. |
