MANUFACTURING METHOD FOR THERMOPLASTIC RESIN MOLDING MATERIAL

To manufacture a thermoplastic resin molding material without any trouble even if a content volume of a compounding material (a compounding material containing reinforcing short fibers as an essential component) in the thermoplastic resin molding material is large.SOLUTION: In a first step, a compounding material comprising a granular, powdery or short fiber thermoplastic resin 3 and reinforcing short fibers 4 as essential components is put into a tank 1 equipped with stirring means and stirred and mixed. In a second step, superheated steam 6 at a temperature higher than a melt temperature of the thermoplastic resin 3 is blown into the tank 1 while stirring is continued. Then, an inner wall surface of the tank 1 is maintained at a temperature lower than the melt temperature of the thermoplastic resin 3 to form a granular mixture 9 of the compounding material containing the thermoplastic resin 3 and the short fibers 4 as essential components. When the thermoplastic resin 3 comes into contact with the superheated steam 6, the thermoplastic resin 3 melts quickly and traps the compounding material containing the short fibers 4 as essential components on a resin surface or entraps the compounding material in the resin. The thermoplastic resin that traps or entraps the compounding material cools to a temperature below the melt temperature when it comes in contact with the inner wall of the tank and becomes the granular mixture 9.SELECTED DRAWING: Figure 2 【課題】熱可塑性樹脂成形材料中に占める配合材（補強用の短繊維を必須成分とする配合材）の含有体積が大きくなっても、支障なく熱可塑性樹脂成形材料を製造する。【解決手段】第1の工程では、粒状、粉状または短繊維状の熱可塑性樹脂３と、補強用の短繊維４を必須成分とする配合材を、撹拌手段を備えた槽１に投入して撹拌・混合する。第２の工程では、撹拌を続けながら、槽１に熱可塑性樹脂３の溶融温度以上の温度の過熱水蒸気６を吹き込む。そして、槽１の内壁面を熱可塑性樹脂３の溶融温度より低く保持して、熱可塑性樹脂３と短繊維４を必須成分とする配合材の粒状混合物９を形成する。熱可塑性樹脂３は過熱水蒸気６に触れると速やかに溶融して短繊維４を必須成分とする配合材を樹脂表面に捕捉し或いは配合材を樹脂中に巻き込む。配合材を捕捉し或いは配合材を巻き込んだ熱可塑性樹脂は、槽の内壁面に接触したとき溶融温度より低い温度に冷却され、粒状混合物９となる。【選択図】図２