Rubber composition for tire and studless tire
The present technology provide a rubber composition including: 100 parts by mass of a diene rubber, from 30 to 100 parts by mass of carbon black and/or a white filler, from 1 to 20 parts by mass of silicone-based microparticles that have an average particle size from 5 to 500 μm and that are three-dimensionally crosslinked, from 0.1 to 10 parts by mass of a nonionic surfactant, and from 1 to 20 parts by mass of thermally expanding microcapsules.
1. A rubber composition for a tire, the rubber composition, comprising:
100 parts by mass of a diene rubber;
from 30 to 100 parts by mass of carbon black and/or a white filler;
from 1 to 20 parts by mass of silicone-based microparticles that have an average particle size from 5 to 500 μm and that are three-dimensionally crosslinked;
from 0.1 to 10 parts by mass of a nonionic surfactant; and
from 1 to 20 parts by mass of thermally expanding microcapsules;
wherein the nonionic surfactant is a compound represented by Formula (d):
where R represents a hydrocarbon group, L represents a single bond or a divalent linking group, R 1 represents a polyalkylene oxide group, R 2 represents a hydrocarbon group, and m and n each independently represent an integer of 1 or greater; a plurality of the R moieties may be the same or different; and in a case where n is an integer of 2 or greater, a plurality of the L moieties, a plurality of the R 1 moieties, and a plurality of the R 2 moieties may be the same or different.
2. The rubber composition for a tire according to claim 1 , wherein the diene rubber contains 30 mass % or greater of at least one rubber selected from the group consisting of a natural rubber (NR), an isoprene rubber (IR), a butadiene rubber (BR), an acrylonitrile-butadiene rubber (NBR), a styrene-butadiene rubber (SBR), a styrene-isoprene rubber (SIR), a styrene-isoprene-butadiene rubber (SIBR), and derivatives of each of these rubbers.
3. The rubber composition for a tire according to claim 2 , wherein the silicone-based microparticles are obtained by three-dimensionally crosslinking a silicone in a liquid polymer containing the nonionic surfactant.
4. The rubber composition for a tire according to claim 1 , wherein the silicone-based microparticles are obtained by three-dimensionally crosslinking a silicone in a liquid polymer containing the nonionic surfactant.
5. A studless tire comprising a tire tread portion produced by using the rubber composition for a tire according to claim 1 .
6. A studless tire comprising a tire tread portion produced by using the rubber composition for a tire according to claim 3 .
7. A studless tire comprising a tire tread portion produced by using the rubber composition for a tire according to claim 2 .
8. A studless tire comprising a tire tread portion produced by using the rubber composition for a tire according to claim 4 .