| 摘要 |
PURPOSE:To obtain the lightguide having excellent flexibility and heat resistance by exposing an argon laser beam to the polyamic acid film on a substrate and curing the film, thereby forming a ployimide film. CONSTITUTION:A polyamic acid soln. 12 is applied on the substrate 11 consisting of glass, etc., the solvent is removed in a vacuum chamber and the soln. at <=100 deg.C, by which the polyamic acid film 12 is formed. This film 12 is irradiated with the argon laser beam 13 thereon and the exposed film 12 is lifted off from the substrate 11 and is dried. Further, this dried film 12 is held by two sheets of the smooth glass substrates 14 and is cured at >=300 deg.C, by which the polyamic acid film 12 is changed to the polyimide film. The waveguide polyimide film 15 is thus obtd. |
