Patent ID: 8465682

Claim:
A process for producing a seamless semiconductive rubber belt having a volume resistivity of 10 4 to 10 12 Ωcm, comprising: an extruding step of using an extruder equipped with a crosshead having an inner cylinder section wherein a spiral flow type groove is made to plasticize an unvulcanized rubber composition having a scorch time t 5 of 10 to 18 minutes, and extruding the composition through the extruder, an unvulcanized rubber belt molding step of shifting, inside the inner cylinder section, a cylindrical mold in a direction substantially orthogonal to the extrusion direction of the unvulcanized rubber composition in the extruder while making the unvulcanized rubber composition into a layer form and allowing the layer-form unvulcanized rubber composition to cover the outside surface of the cylindrical mold, thereby yielding an unvulcanized rubber belt, molded body, and a vulcanizing step of vulcanizing the unvulcanized rubber belt molded body, thereby yielding the semiconductive rubber belt.