| 摘要 |
PURPOSE:To form in a high precision, by a method wherein a thermoplastic resin film is fed between two press rolls, at least one rigid roll of which is wound at close intervals by the use of a metal wire and is kept at lower than a softening point of the film, and is cooled rapidly after being pressurized to form a wavy pattern. CONSTITUTION:A tension in a transverse direction is applied to a thermoplastic resin film 1 by means of a widening roll 4 positioned following two drag rolls 3A and 3B, and the film is formed in a wavy pattern by means of two press rolls 5A and 5B located following two pinch rolls 3C and 3B. At least one roll of the press rolls 5A and 5B is rigid, and a rigid metal wire having a smooth surface and a diameter of 0.5-2mm. is wound at close intervals around said roll. A surface temperature of said press roll is allowed to remain 60-160 deg.C which is lower than a softening point of the film, and the wavy pattern is formed under a pressurized forming pressure of about 300kg/cm. The film is then cooled rapidly by means of cooling devices 7A and 7B to solidify the wavy pattern. |
