METHOD FOR PRODUCING RUBBER WET MASTER BATCH, THE RUBBER WET MASTER BATCH, AND RUBBER COMPOSITION CONTAINING THE RUBBER WET MASTER BATCH

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a rubber wet master batch in which deterioration of rubber is suppressed and which is excellent in rubber properties, especially in rubber strength.SOLUTION: A method for producing a rubber wet master batch includes a heating step in which dehydration, drying, and plasticization of a filler-containing rubber coagulum are conducted in one stage by using a single-screw extruder and heating the rubber coagulum to 160-200°C. The single-screw extruder comprises a screw and an outer cylinder in which slits extending along a length direction (screw-shaft direction) of the outer cylinder are formed in an inner wall. When a width of each of the slits is defined as A and a clearance between the crest of the screw and the inner wall of the cylinder is defined as B, the product of A and B (AB(Y)) in the downstream side of the outer cylinder in the screw-shaft direction, and the product of A and B (AB(X)) in the upstream side of the outer cylinder in the screw-shaft direction, satisfy the following relation (1): 0AB(Y)/AB(X)0.9 ...(1).