| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem of abnormal foaming that occurs during firing of a polyimide film and causes large undulation on a graphite sheet formed therefrom. SOLUTION: A method for producing a graphite sheet comprises: stretching a gel film obtained by heating, drying and partially imidizing pyromellitic dianhydride and 4,4'-diaminodiphenyl ether; imidizing the gel film so as to obtain a polyimide film having edge-tear resistance per unit thickness of 9,000-15,000 N/(20 mm*mm) and thickness of 30-150 μm; and raising temperature of the polyimide film in an inert gas at a constant rate and firing the same at 2,400-3,500°C so as to convert the same into graphite. COPYRIGHT: (C)2010,JPO&INPIT |
