MINUTE FIBROUS CARBON MATERIAL DERIVED FROM CELLULOSE RAW MATERIAL AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a new minute fibrous carbon material which can inexpensively be mass produced from a cellulose raw material without causing collapse/ aggregation of microfibril in the cellulose raw material and to provide a method for producing the same. SOLUTION: In order to prevent collapse of microfibril in the cellulose raw material, the cellulose is dried with avoiding surface tension of water contained in the cellulose and crystallization of water in the freezing process of water to cause the collapse and then the cellulose is carbonized or graphitized. The drying method can be carried out by using any one of (1) swelling the cellulose raw material with liquid carbon dioxide, etc., and drying the cellulose raw material at the critical point, (2) swelling the cellulose raw material with an organic solvent and subjecting it to drying under heating or freeze-drying and (3) subjecting the cellulose raw material in a swollen state with water to rapid freeze-drying so as not to form ice crystal. The material thus dried is carbonized/graphitized so that aggregation between the microfibrils or collapse of microfibril structure is prevented and a bar-like or net-like minute fibrous carbon material in a preserved state of microfibril can be processed.