| 摘要 |
PURPOSE:To productively prepare an unstretched film which is short of thickness deviation in the direction of film length by a method wherein thermoplastic synthetic resin is extruded in the form of fused film directly into a cooling water tank, cooled and cured in the current of cooling water and accepted. CONSTITUTION:In a cooling water tank 2 is provided a slit 7 composed of a pair of flat plates 6, 6 (it is preferable that the distance between the water surface and the top 6a of a flat plate is about 5-150mm. and the slit width is about 1-20mm.) and the cooling water introduced from an inlet 3 is exhausted from an outlet 4 over a weir plate 5. By the use of the said device, fused film Fm of the thermoplastic synthetic resin extruded from a die 1 is dropped directly into the cooling water tank 2, cooled, cured and the unstretched film obtained Fs is accepted outside the cooling water tank 2 through the slit 7, a guide roller 8, a nip roller 9 (at this time the fused film Fm passing through the slit 7 runs down with the current of cooling water on both its sides and it is cooled and cured efficiently). |
