To provide an extruder for efficiently producing a polypropylene compsn. reduced in fish eye containing an elastomer component comprising an α-olefin copolymer of a different kind without damaging productivity and quality.
An extruder mainly consists of the melting part provided on this side of a kneading part to perfectly melt a resin and the kneading part having a kneading element capable of applying shearing strain to the molten resin uniformly and capable of setting an A-value, which is calculated according to A=η.Σ(S).n (wherein η is the shearing viscosity of the resin of the kneading part, S is the shearing strain quantity in the element part and n is the number of times of shearing strain applied to the resin by element flights) to 109 or more.
OKUMURA SHOGO
WATANABE FUMINAO
HASHIZUME SHINJI
KOBE STEEL LTD