Flynn, Thiel, Boutell & Tanis, P.C.
Substance including natural organic substance fine powder
 Materials containing fine natural organic material particles are disclosed. As the fine particles, superfine silk fibroin particles are produced by a process comprising a first step of comminuting silk fibroin into coarse particles with dry mechanical comminuting means, a second step of comminuting the coarse silk fibroin particles into fine particles with dry mechanical comminuting means, and a third step of comminuting the fine silk fibroin particles into superfine particles with an average particle diameter of 10 .mu.m or below with dry mechanical comminuting means, the silk fibroin particles being beta-treated during or after at least one of the first to third comminuting steps. Specific examples of the material are films, sheets, paints, fiber treating materials, etc. 
Idemitsu Petrochemical Co., Ltd.
B Y B C C C B C B C C B B B B C B C C B C B B C Y C
B32B Y10T B32B C08L C09D C08J B32B C08L B32B C08K C08J B32B B32B B32B B32B C09D B32B C08L C08J B32B C08L B32B B32B C09D Y10T C08L
inventional additional inventional inventional inventional inventional inventional inventional inventional additional inventional additional inventional inventional inventional inventional inventional inventional additional inventional inventional inventional inventional inventional additional inventional
Satoshi Takaharu Fumioki Masahiro Shigeru Nobuo Nobutaka Atsuhiko
Mikami Yasue Fukatsu Sano Ohyama Kusamoto Sasaki Ubara