Method of manufacturing colorless transparent polyimide film having impregnated glass fabric and of flattening surface thereof

摘要

Disclosed is a method of manufacturing a colorless transparent polyimide film having impregnated glass fabric, wherein the surface of the polyimide film substrate having impregnated glass fabric is flattened by two flattening steps using a roll-to-roll process, thereby solving problems with an increase in surface roughness of the polyimide substrate when manufacturing the polyimide film having impregnated glass fabric in order to enhance thermal and mechanical properties of a film for use in flexible display substrates and in cover windows for flat panel displays and mobile phones. As the surface roughness of the polyimide film having impregnated glass fabric is flattened to the level of ones of nm from the level ranging of tens of nm to ones of μm, a thin film transistor process can be performed on the polyimide film substrate and the polyimide film is increased in optical transmittance and transparency and can thus be utilized as flexible display substrates and cover windows for flat panel displays and mobile phones.

主权项

1. A method of manufacturing a polyimide film having impregnated glass fabric, comprising:
(1) impregnating glass fabric with a polyamic acid solution, thus obtaining a polyamic acid film having impregnated glass fabric; (2) flattening the polyamic acid film having impregnated glass fabric obtained in (1) (first flattening process) at a temperature between the Tg of the polyamic acid film and the imidization temperature of the polyamic acid; (3) subjecting the polyamic acid film obtained in (2) to imidization, thus obtaining a polyimide film having impregnated glass fabric; and (4) flattening the polyimide film having impregnated glass fabric obtained in (3) (second flattening process) at a temperature between the Tg of the polyimide film and the thermal decomposition temperature of the polyimide film; wherein the flattening steps are performed by applying pressure using cylindrical rollers or flat plates having a surface roughness of 0.5 to 2 nm.