Semiconductive rubber belt, and process for producing the same
AssigneeToyo Tire & Rubber Co., Ltd.
InventorTakahiro Nakagawa
Life of this patent
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Abstract
An object of the present invention is to provide a semiconductive rubber belt wherein a variation in the electric resistance is decreased, in particular, in the belt circumferential direction so that high-quality images can be formed, and a process for producing the same. In order to achieve the object, in a case where on any single straight line extended in the belt circumferential direction, the maximum value of the molecular orientation ratio correction value MOR-C of the semiconductive rubber belt, the minimum value thereof, and the average thereof are set to satisfy a specified relationship.
Claims2
A process for producing a seamless semiconductive rubber belt having a volume resistivity of 104 to 1012 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 t5 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.
Dependencies are inferred from the claim text.