| 摘要 |
PURPOSE:To manufacture oriented resin film, the thickness distribution in the width direction of which is uniform, by a method wherein the thicker portion of resin film is detected with a beta-ray film thickness gage and is blasted with hot air, the temperature of which is higher than that of hot air blasted to the thinner portion. CONSTITUTION:The thickness distribution in the width direction of oriented film 1 sent from an annealing furnace is read every unit time (such as every 15min) with a beta-ray film thickness gage and converted into electric signals so as to actuate heater elements corresponding to the thicker portions of the film in order to make the temperature of the hot airs discharged from the portions occupied by said heater elements higher than that of the hot airs discharged from the other portions, resulting in lowering the melt viscosity of the resin of the thicker film portions and consequently stretching and thinning the thicker film portions by the shrinkage stress of the thinner film portions. Thus, oriented film, the thickness distribution in the width direction of which is uniform, is finally manufactured.
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