In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.

In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.

The present disclosure provides a tire which makes it possible to reduce the increase in hardness and the decrease in wet grip performance from before to after heat aging. The present disclosure relates to a tire including a tread, the tread including an elastomer composition containing a styrene elastomer and urethane particles, the tread satisfying the following relationship (1): (M100a−M100f)/M100f×100≤38 wherein M100f represents the stress at 100% elongation (23° C.) before heat aging, and M100a represents the stress at 100% elongation (23° C.) after heat aging.

The present disclosure provides a tire which makes it possible to reduce the increase in hardness and the decrease in wet grip performance from before to after heat aging. The present disclosure relates to a tire including a tread, the tread including an elastomer composition containing a styrene elastomer and urethane particles, the tread satisfying the following relationship (1): (M100a−M100f)/M100f×100≤38 wherein M100f represents the stress at 100% elongation (23° C.) before heat aging, and M100a represents the stress at 100% elongation (23° C.) after heat aging.

An adhesive for a tennis ball of the present disclosure includes base rubber and a filler. The base rubber contains, as a main component thereof, liquid rubber having a number average molecular weight of not less than 10,000. The filler has an average nitrogen specific surface area of not less than 40 m.sup.2/g. A tennis ball of the present disclosure includes a hollow core made of a rubber material. The core includes two hemispherical half cores. The two half cores are adhered to each other by using the adhesive for a tennis ball.

An adhesive for a tennis ball of the present disclosure includes base rubber and a filler. The base rubber contains, as a main component thereof, liquid rubber having a number average molecular weight of not less than 10,000. The filler has an average nitrogen specific surface area of not less than 40 m.sup.2/g. A tennis ball of the present disclosure includes a hollow core made of a rubber material. The core includes two hemispherical half cores. The two half cores are adhered to each other by using the adhesive for a tennis ball.

It is an object to provide a tire having well-improved fuel efficiency, wet grip performance, abrasion resistance, and wet grip performance at a later stage of abrasion. Provided is a tire comprising a tread part of a rubber composition comprising a rubber component comprising an isoprene-based rubber and a styrene-butadiene rubber, wherein a vinyl content of the styrene-butadiene rubber is greater than 26 mol %, wherein a given ratio A of an ash content of the rubber composition is greater than 25 mol %, wherein the tread part comprises two or more circumferential main grooves extending in a tire circumferential direction, and land parts partitioned by the circumferential main grooves, wherein at least one land part of the land parts comprises at least one given flask-like circumferential groove extending in the tire circumferential direction.

It is an object to provide a tire having well-improved fuel efficiency, wet grip performance, abrasion resistance, and wet grip performance at a later stage of abrasion. Provided is a tire comprising a tread part of a rubber composition comprising a rubber component comprising an isoprene-based rubber and a styrene-butadiene rubber, wherein a vinyl content of the styrene-butadiene rubber is greater than 26 mol %, wherein a given ratio A of an ash content of the rubber composition is greater than 25 mol %, wherein the tread part comprises two or more circumferential main grooves extending in a tire circumferential direction, and land parts partitioned by the circumferential main grooves, wherein at least one land part of the land parts comprises at least one given flask-like circumferential groove extending in the tire circumferential direction.

Antimicrobial polymer composite materials are disclosed that are suitable for making oral devices used in dental applications, such as denture bases. Acrylic resin composite materials comprising antimicrobial polymers and antimicrobial fillers provide reduction in common oral microorganisms after long-term aging, with reduced release rate of antimicrobial agents from the composite material. Antimicrobial polymers are prepared from compositions comprising acrylate and/or methacrylate monomers and polymerizable quaternary ammonium silicon-containing compounds.

A rubber compound having at least two glass transition temperatures Tg1 and Tg2 is based on at least two rubber compositions C1 and C2, C1 comprising at least one elastomer E1 with Tg1, C2 comprising at least one elastomer E2 with Tg2 and a reinforcing filler, E2 being different from E1, where Tg1 is above or equal to -50° C., the rubber compound satisfies Tg1-Tg2 ≥ 23° C. and has a loss factor profile exhibiting the change in tan δ as a function of the temperature in °C. over a range extending from -80° C. to 60° C. at a frequency of 10 Hz and a constant stress of 0.7 MPa and exhibiting one or more peaks, such that all the tan δ peaks present at a temperature above Tg1 have a width at half height less than or equal to 23° C.; and E1 is predominant.