| 摘要 |
PCT No. PCT/JP96/03238 Sec. 371 Date May 7, 1998 Sec. 102(e) Date May 7, 1998 PCT Filed Nov. 5, 1996 PCT Pub. No. WO97/17893 PCT Pub. Date May 15, 1997To provide a polytetrafluoroethylene granular powder for molding and a process for preparing the granular powder, in which the granular powder contains only a small number of coarse particles, is obtained with good tumbling efficiency and further no organic liquid is required to be used. The process is for preparing a polytetrafluoroethylene granular powder for molding by granulating a polytetrafluoroethylene powder through tumbling with a granulator having a rotating inclined disc and a rotating side plate; characterized in that the granulator: (1) comprises a disc inclined to a horizontal level and a side plate provided on the periphery of the disc, (2) has the side plate assembled in one unit with the disc and rotating together, and (3) is equipped with an agitator positioned eccentrically to the center of a vortex of the polytetrafluoroethylene powder which is caused by tumbling, or the granulator: (1) comprises a disc inclined to a horizontal level and a side plate provided on the periphery of the disc, (2) has the side plate separated from the disc and being rotatable around the periphery of the disc, and (3) is equipped with an agitator positioned eccentrically to the center of a vortex of the polytetrafluoroethylene powder which is caused by tumbling, and that the granulation is carried out by tumbling the polytetrafluoroethylene powder wetted with an aqueous solution containing a surfactant.
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