Abstract: A die 6 includes a central member 6a, an injection hole formed from a surface of the central member 6a to an inside, a plurality of nozzles formed from an opposite surface of the central member 6a to the inside and connected to the injection hole, a heat source provided inside the central member 6a, and a plurality of heat insulating portions 31a provided inside the central member 6a. The plurality of heat insulating portions 31a extend from an outer peripheral side of the central member 6a toward an inner side of the central member 6a in plan view.

Abstract: A performance of a die is improved. An injection hole IH, a nozzle NZa and a nozzle NZb are formed in a center member DIa of a die DI to extend from an extrusion surface ES to an injection surface IS. A heat source HT and a plurality of heat insulating layers HI1 are arranged inside the center member DIa. One of the plurality of heat insulating layers HI1 is adjacent to the nozzle Nzb and is closer to the extrusion surface ES than the heat source HT. The other of the plurality of heat insulating layers HI1 extends in a direction from the extrusion surface ES toward the injection surface IS at a position being farther from the nozzle NZb than the heat source HT.