| 摘要 |
PROBLEM TO BE SOLVED: To suppress the air retention between cord plies without applying boring. SOLUTION: A ply material manufacturing method for forming the ply material 4 by topping a cord parallel body 3 with unvulcanized rubber G includes a topping/extrusion molding process for obtaining the ply material 4 of a prescribed cross-sectional shape by passing the rubber G and the cord parallel body 3 in the cord length direction into the molding opening 13 of an extrusion head 7 with a die plate 6 having the molding opening 13 set at the front end. The die plate 6, by having at least one convex stripe projection 22 which slightly protrudes from wall surfaces 20a and 20b and stretches in the cord length direction on the upper and lower wall surfaces 20a and 20b of the molding opening 13, the topping/extruding molding process forms at least one concave groove 23 for exhaust stretching in the cord length direction between the cords on the upper and lower surfaces 4a and 4b of the ply material 4. COPYRIGHT: (C)2010,JPO&INPIT |
