Composition for tire tread comprising resin alternative to process oil
The present invention relates to a composition for a tire tread, comprising a resin alternative to a process oil. The composition for a tire tread, according to the present invention, can satisfy basic physical properties required as a tire, such as tensile strength, wear resistance, durability, and hardness, and improve the gripping force without a big increase in rolling resistance. A tire manufactured from the composition has the improved gripping force, particularly on wet road surfaces, and thus may be used for manufacturing a high-performance tire with excellent breakability, thereby being capable of increasing product competitiveness.
1. A composition for a tire tread, comprising at least one resin selected from the group consisting of a methylstyrenated phenol-based resin, and a hydrocarbon-based resin, and at least one resin selected from the group consisting of a terpene phenol resin and a hydrogenated hydrocarbon-based resin,
wherein the methylstyrenated phenol-based resin and the hydrocarbon-based resin do not comprise a softening point measured by ASTM E 28, and
wherein the hydrogenated hydrocarbon-based resin and the terpene phenol resin comprise a softening point measured by ASTM E 28.
2. The composition for the tire tread according to claim 1 , wherein the composition for the tire tread does not comprise a process oil.
3. The composition for the tire tread according to claim 1 , wherein the weight-average molecular weight of the methylstyrenated phenol-based resin is 200 to 5,000 g/mol; the weight-average molecular weight of the hydrocarbon-based resin is 400 to 5,000 g/mol; the weight-average molecular weight of the hydrogenated hydrocarbon-based resin is 500 to 5,000 g/mol, and its Tg is 30 to 100° C. and its softening point is 100 to 150° C.; and the weight-average molecular weight of the terpene phenol resin is 500 to 5,000 g/mol, and its Tg is 20 to 100° C. and its softening point is 100 to 150° C.
4. The composition for the tire tread according to claim 1 , comprising the methylstyrenated phenol-based resin and the terpene phenol resin.
5. The composition for the tire tread according to claim 1 , comprising a first resin selected from the group consisting of a methylstyrenated phenol-based resin and a hydrogenated hydrocarbon-based resin, and a second resin selected from the group consisting of a terpene phenol resin and a hydrocarbon-based resin, and the weight ratio of the first resin to the second resin is 30:70 to 70:30.
6. The composition for the tire tread according to claim 5 , wherein the first and second resins respectively have a weight ratio of 1 to 10 weight relative to 100 parts by weight of a raw material rubber.
7. The composition for the tire tread according to claim 1 , comprising 1 to 10 parts by weight of each of a first resin selected from the group consisting of a methylstyrenated phenol-based resin and a hydrogenated hydrocarbon-based resin, and a second resin selected from the group consisting of a terpene phenol resin and a hydrocarbon-based resin, 1 to 3 parts by weight of a homogenizing agent, 1 to 5 parts by weight of zinc oxide, 10 to 40 parts by weight of silica, 1 to 10 parts by weight of a silane coupling agent, 10 to 40 parts by weight of carbon black, 1 to 3 parts by weight of stearic acid, 1 to 3 parts by weight of sulfur and 1 to 5 parts by weight of a curing accelerator based on 100 to 160 parts by weight of a raw material rubber.
8. The composition for the tire tread according to claim 2 , wherein the value of Tan δ at 0° C. of the composition for the tire tread is as high as 10% or more compared to the composition for the tire tread containing the process oil.
9. The composition for the tire tread according to claim 2 , wherein the value of Tan δ at 70° C. of the composition for the tire tread is as high as 4% or less compared to the composition for the tire tread containing the process oil.