| 摘要 |
PURPOSE:To uniformarize the temperature distribution of a cooled stretched film as far as possible thereby preventing it from sagging, by using a duct for discharging cooling air whose chamber is divided into a plurality of independent compartments. CONSTITUTION:Of ducts 2, each of four pairs of upper and lower ducts near an annealing treatment furnace 19 has a chamber that is divided into nine compartments, and cooling air is fed to these compartments or conduits 12 connecting these compartments and is blown through the compartments against a resin film 1. Other air is led to a duct whose chamber is not divided and is blown against the resin film 1. The temperature of the film in the cooling furnace is measured by an infrared thermometer 14, equi-distanced marking holes are formed in the film with the holes arranged in the direction of the width thereof, the distance between the holes is compared with the average value, and the amount of air discharged from the compartment corresponding to the particular position of the film is controlled, so that cooling of that part of the film is made equal to cooling of the other part of the film. |
