| 摘要 |
PURPOSE: To produce a stretched plastic film in an accurately controllable manner by providing a means passing a stable water pressure liquid controllable in wt., temp. and viscosity through the plastic material on a hollow cylinder to perform biaxial orientation. CONSTITUTION: A tube 1 wherein a plurality of kinds of uniaxially or biaxially stretched thermoplastic materials are laminated is cooled in a form of a bubble body 3 just under a die by cooling air 4 and quenched by a quenching guide ring 5 to perfectly form a membrane. A plastic cylinder is immersed by extrusion rollers R1, R2, R3 and a film is longitudinally stretched by the rotational speed of the roller R3. Next, a water pressure body is injected into the flat tube to accurately stretch the tube by the rollers R2. R3 and, if the lower part speed of the plastic cylinder increases, the pressure of the water pressure body on a lower roller increases and, since a pressure body is integrally and uniformly expanded in a formed cylinder, the plastic cylinder is stretched in three axial directions and a cylindrical body has stable stretching characteristics in long and short axis directions. |
