PROCESS FOR PRODUCING WET RUBBER MASTERBATCH, WET RUBBER MASTERBATCH, AND RUBBER COMPOSITION CONTAINING WET RUBBER MASTERBATCH

WIPO Patent Application WO/2015/194197

A1

A process for producing a wet rubber masterbatch, the process including a heating step in which dehydration, drying, and plastication of filler-containing rubber coagulates are conducted in one stage by using a single-screw extruder to heat the rubber coagulates to 160-200°C, the single-screw extruder comprising a screw and a cylinder which has, formed in the inner wall, slits that extend along the length direction of the cylinder (screw-shaft direction). When the width of each slit is expressed by A and the clearance between the top of the screw thread and the inner wall of the cylinder is expressed by B, then the product of A and B in the portion of the cylinder on the downstream side along the screw-shaft direction, AB(Y), and the product of A and B in the portion of the cylinder on the upstream side along the screw-shaft direction, AB(X), satisfy the relationship (1): 0