Shaping roll for melt extrusion molding, shaping roll assembly for melt extrusion molding, and melt extrusion molding method

A shaping roll for melt extrusion molding used for melt extrusion molding of thermoplastic resin, the shaping roll for melt extrusion molding comprising:

• a roll body part having a heat medium passage internally and cutouts on outer surfaces of both end portions;
• and
• a cylindrical member fitted into the cutouts in the both end portions of the roll body part;
• the roll body part comprising a first metal material having a thermal conductivity of 40 W/m·K or more;
• the cylindrical member comprising a second metal material having a thermal conductivity of 20 W/m·K or less;
• and
• the cylindrical member being at least partially joined to the cutouts of the roll body part.

A shaping roll assembly for melt extrusion molding comprising:

• a shaping roll for melt extrusion molding;
• a pressure roll disposed facing the shaping roll for melt extrusion molding;
• the shaping roll for melt extrusion molding comprising
• a metal roll body having a heat medium passage internally;
• a first cylinder covering a surface of a middle portion of the roll body part;
• a second cylinder covering surfaces of both end portions of the roll body part;
• the first cylinder comprising a first metal material having a thermal conductivity of 40 W/m·K or more;
• the second cylinder comprising a second metal material having a thermal conductivity of 20 W/m·K or less;
• and
• the first cylinder and the second cylinder being at least partially joined to each other.

A shaping roll assembly for melt extrusion molding comprising:

• a shaping roll for melt extrusion molding;
• a pressure roll disposed facing the shaping roll for melt extrusion molding;
• the shaping roll for melt extrusion molding comprising
• a roll body part having a heat medium passage internally and cutouts on outer surfaces of both end portions;
• a cylindrical member fitted into the cutouts in the both end portions of the roll body part;
• the roll body part comprising a first metal material having a thermal conductivity of 40 W/m·K or more;
• the cylindrical member comprising a second metal material having a thermal conductivity of 20 W/m·K or less;
• and
• the cylindrical member being at least partially joined to the cutouts of the roll body part.

A melt extrusion molding method using a shaping roll assembly for melt extrusion molding comprising a shaping roll for melt extrusion molding and a pressure roll disposed facing the shaping roll for melt extrusion molding, comprising steps of:

• pushing molten thermoplastic resin out from a die;
• passing molten thermoplastic resin through a gap between the shaping roll for melt extrusion molding and the pressure roll to obtain a sheet molded article;
• the shaping roll for melt extrusion molding comprising:
• a metal roll body having a heat medium passage internally;
• a first cylinder covering a surface of a middle portion of the roll body part;
• a second cylinder covering surfaces of both end portions of the roll body part;
• the first cylinder comprises a first metal material having a thermal conductivity of 40 W/m·K or more;
• the second cylinder comprises a second metal material having a thermal conductivity of 20 W/m·K or less;
• and
• the first cylinder and the second cylinder are at least partially joined to each other.

A melt extrusion molding method using a shaping roll assembly for melt extrusion molding including a shaping roll for melt extrusion molding and a pressure roll disposed facing the shaping roll for melt extrusion molding, comprising steps of:

• pushing molten thermoplastic resin out from a die;
• passing molten thermoplastic resin through a gap between the shaping roll for melt extrusion molding and the pressure roll to obtain a sheet molded article;
• the shaping roll for melt extrusion molding comprising:
• a roll body part having a heat medium passage internally and cutouts on outer surfaces of both end portions;
• a cylindrical member fitted into the cutouts in the both end portions of the roll body part;
• the roll body part comprising a first metal material having a thermal conductivity of 40 W/m·K or more;
• the cylindrical member comprising a second metal material having a thermal conductivity of 20 W/m·K or less;
• and
• the cylindrical member being at least partially joined to the cutouts of the roll body part.