To continuously and efficiently produce a kneaded material which can improve the dispersion and distribution properties of a chemical and is excellent in uniformity.

Rubber G sent quantitatively from a rubber supply means 2 and the chemical C sent quantitatively from a chemical supply means 3 are charged simultaneously into a first single screw type rubber extruder 4 to knead primarily kneaded rubber G1. After that, the primarily kneaded rubber G1 is further kneaded by a second twin taper screw type rubber extruder 5 to form the kneaded material G0. The spiral pitch P of the taper screw shaft 31 of the second rubber extruder 5 is made to be 1.1-1.5 times as large as the diameter d on the large diameter side of the taper screw shaft 31.

COPYRIGHT: (C)2005,JPO&NCIPI