| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rubber composition for sidewalls which has improvement in mileage, driving stability, resistance against breakage, elongation at break, and processability in a well-balanced way, and can prevent the shortage of spew at the time of demolding tire and to provide a pneumatic tire using the same. <P>SOLUTION: The rubber composition for sidewalls includes 5-60 mass%, as a total content, of butadiene rubber synthesized using a butadiene rubber containing 1,2-syndiotactic polybutadiene crystal and a rare earth catalyst, 7-60 mass% of terminal modification butadiene rubber, and 20-70 mass% of isoprene rubber, in 100 mass% of the rubber component. In the rubber composition, based on 100 pts.mass of the rubber component, the total content of carbon black having a nitrogen adsorption specific surface area of 25-120 m<SP POS="POST">2</SP>/g and silica having a nitrogen adsorption specific surface area of 70-250 m<SP POS="POST">2</SP>/g is 20-40 pts.mass, and the content of zinc oxide is 3.6-16 pts.mass. <P>COPYRIGHT: (C)2013,JPO&INPIT |
