Patent ID: 6517653
Filing Date: 2003-02-11
Classification: B60C,C08J,C08K,C08L,Y10T

Abstract:
A process for improving the cured adhesion of a precured rubber component in a pneumatic tire to an uncured rubber component in a tire comprising(A) assembling the tire so a precured rubber component is in contact with an uncured rubber component wherein said precured rubber component comprises (1) from 40 to 100 parts by weight of a rubber, per 100 parts by weight of total rubber in said precured rubber compound, selected from the group consisting of natural rubber, emulsion-polymerized styrene-butadiene rubber and mixtures thereof, wherein said rubber contains from 0.5 to 3 phr of a fatty acid inherently present in the natural rubber or present from the polymerization reaction to produce the styrene-butadiene rubber; (2) from 3 to 80 phr of precipitated silica; (3) from 0.8 to 3.5 phr of an accelerator; (4) from 1.0 to 3.5 phr of sulfur, wherein the weight ratio of accelerator to sulfur ranges from 0.5:1 to 3.5:1; (5) from 1 to 10 phr of zinc oxide; and (6) 0 phr of any fatty acid other than the 0.5 to 3 phr present in said natural rubber and emulsion-polymerized styrene-butadiene rubber; and (B) vulcanizing the tire at a temperature ranging from 120Â° C. to 200Â° C.