The present invention provides a rubber composition for a sidewall, which improves fuel economy, handling stability, tensile strength at break, elongation at break, and processability in a balanced manner, and which can also suppress the occurrence of broken spews during demolding of a resulting tire; and a pneumatic tire formed from the rubber composition. The present invention relates to a rubber composition for a sidewall, comprising a rubber component having: a combined amount of a 1,2-syndiotactic polybutadiene crystal-containing butadiene rubber and a butadiene rubber synthesized in the presence of a rare earth catalyst of 5 to 60% by mass; an amount of a terminally modified butadiene rubber of 7 to 60% by mass; and an amount of an isoprene-based rubber of 20 to 70% by mass, each based on 100% by mass of the rubber component, wherein the rubber composition has: a combined amount of a carbon black having a nitrogen adsorption specific surface area of 25 to 120 m2/g and a silica having a nitrogen adsorption specific surface area of 70 to 250 m2/g of 20 to 40 parts by mass; and an amount of zinc oxide of 3.6 to 16 parts by mass, each per 100 parts by mass of the rubber component.
Rubber composition for side wall and pneumatic tire
2016-03-01
Patent
Electronic Resource
English
TIRE SIDE WALL RUBBER COMPOSITION AND PNEUMATIC TIRE USING THE SAME
European Patent Office | 2015
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