| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent the collapse of a bead core in vulcanization. <P>SOLUTION: A green tire forming process includes a bead core forming step having: a step S1 of forming a rubberized wire 11 by covering a bead wire 10 with a topping rubber G; a step S2 of forming a green bead core 12 by winding the rubberized wire 11 many times; and a heating step S3 of heating the green bead core 12 in an oven to semi-cure the green bead core. The topping rubber G is formed from a rubber powder-added rubber composition prepared by blending 30-100 pts.mass vulcanized rubber powder and 90-180 pts.mass carbon black per 100 pts.mass unvulcanized rubber material containing 25-90 pts.mass natural rubber and 10-75 pts.mass styrene-butadiene rubber. Scorching time T<SB>a</SB>10 (unit:minute) of the topping rubber G at 160°C after the heating step S3 is controlled to be≤80% of scorching time T<SB>b</SB>10 (unit: minute) before heating step S3 by heating in the heating step S3. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
