| 摘要 |
PURPOSE:To make it possible to obtain a fluorine plastic film excellent in optical property and flatness, by setting the surface temperature of a cooling roll to 80-140 deg.C, and blowing hot air having a temperature of 50-160 deg.C against the film on the cooling roll. CONSTITUTION:A melted fluorine resin extruded from a T-die 2 is brought in contact with a first cooling roll 3 to be cooled and solidified, and the resulting flat film 4 is taken up. The temperature of the first cooling roll 3 is set to 80- 140 deg.C and hot air having a temperature of 50-160 deg.C is blown against the film on the cooling roll. If the surface temperature of the cooling roll 3 is below 80 deg.C, the adhesion of the melted fluorine resin film to the roll surface is unsatisfactory, and if the temperature is over 140 deg.C, the adhesion to the roll surface is too high, resulting in difficulty in the smooth take-up. If the temperature of the hot air is below 50 deg.C, uneven cooling would result in sometimes, and if it is over 160 deg.C, the adhesion of the melted film to the roll surface is too high, resulting in difficulty in the take-up. |
