KR20100060817A - Tread compound with improved wear and rolling resistance properties - Google Patents

Abstract

PURPOSE: A tire tread rubber composition is provided to obtaining excellent exothermic property and dynamic properties using specific silica and to manufacture the tire having superior abrasion property and rotation resistance. CONSTITUTION: A tire tread rubber composition comprises crude rubber 100.0 parts by weight, silica 5~15 parts by weight, and carbon black 35~50 parts by weight. The silica has BET of 190~210 m^2/g and an average particle size distribution of 6.0~7.0. The carbon black has DBP oil absorption of 120~140 ml/mg. The crude rubber is selected from a natural rubber, a synthetic rubber, or their mixed rubber.

Description

Tire tread rubber composition with improved wear performance and rolling resistance performance {TREAD COMPOUND WITH IMPROVED WEAR AND ROLLING RESISTANCE PROPERTIES}

The present invention relates to a tire tread rubber composition having improved wear performance and rolling resistance performance, and more particularly, to a tire tread rubber composition having improved wear and rolling resistance performance by applying specific silica.

Tire wear is a phenomenon in which the surface of the tire tread rubber which is grounded to the ground due to the friction between the tire and the road surface is worn out. This wear phenomenon is caused by various factors such as the lateral force when turning a curve during driving and the final force during driving and braking. The wear of such a tire has a great influence on the life and braking properties of the tire, so that it is required to have excellent wear resistance for safe driving and cost reduction of the tire.

In order to reduce the rolling resistance of the tire and improve the wear performance, it is possible to adjust the pattern shape and the tire ground area on the structural side, adjust the rigidity of the bead portion, reduce the overall weight of the tire, and reduce the hysteresis loss on the rubber composition side. Efforts are underway to reduce it.

As a way to reduce the weight of the tire, there is a method of reducing the tread depth, but this is difficult to apply due to the shortened tire life, and the method of reducing the tread depth while using rubber with improved wear performance by using nanomaterials is studied. However, this too has not been put to practical use.

In addition, as a method for improving the rotational resistance performance in the rubber composition, there is a limit to increase the addition amount of carbon black and to reduce the particle size, there is a limit, even when using the method of replacing the use of carbon black with some silica, etc. The resistance is helpful but has the disadvantage of lowering the wear performance.

An object of the present invention is to solve the problems of the prior art as described above, in place of the carbon black conventionally used mainly for truck buses, by using silica having a specific particle structure to improve the wear performance and rolling resistance performance It is to provide a tread rubber composition.

The tire tread rubber composition according to the present invention has 5 to 15 parts by weight of silica having a BET of 190 to 210 m ² / g and an average particle size distribution (ASD, 6.0 to 7.0) based on 100 parts by weight of the raw material rubber. And 35 to 50 parts by weight of carbon black having an iodine adsorption value of 135 to 150 mg / g and a DBP oil absorption of 120 to 140 ml / mg.

The raw material rubber used in the present invention is not particularly limited in kind, and natural rubber, synthetic rubber or mixed rubber thereof may be used, and it is preferable to use 100% diene-based natural rubber as an example.

The silica used in the present invention preferably has a BET value of 190 to 210 m ² / g, an average particle size distribution of 6.0 to 7.0, and a BET value of less than 190 m ² / g. If it exceeds 210m ² / g, the dispersing performance decreases, which is not preferable. The average particle size distribution value is measured by a laser particle analyzer, and when the average particle size distribution value is less than 6.0, Tan δ becomes large, resulting in poor rotational resistance performance, and when the average particle size distribution value is greater than 7.0, it is difficult to exhibit wear performance. Not.

In the rubber composition of the present invention, the amount of silica is preferably 5 to 15 parts by weight, but when the amount of the silica is less than 5 parts by weight, the effect of improving the rolling resistance is insufficient, which is undesirable. It is not preferable because the wear performance is lowered.

The carbon black used in the present invention preferably has an iodine adsorption value of 135 to 150 mg / g and a DBP oil absorption of 120 to 140 ml / mg. When the iodine adsorption value and the DBP numerical range are out of the above ranges, it is not preferable because the structure of carbon black goes beyond the development degree and the compounding and extrusion processability worsens.

In the rubber composition of the present invention, the carbon black is preferably used in an amount of 35 to 50 parts by weight. When the carbon black is used in an amount of less than 35 parts by weight, the wear performance is deteriorated. It is not preferable because the resistance performance falls.

To the rubber composition of the present invention, additives for conventional rubber compositions, such as zinc oxide, antioxidants, active agents, stearic acid, waxes, process oils, sulfur, accelerators, and the like, may be appropriately selected and added. And the amount used is known in the art.

The tire tread rubber composition of the present invention is excellent in wear, heat generation and dynamic properties by using a specific silica, and when using the rubber composition of the present invention can produce a tire excellent in wear performance and rolling resistance performance.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited thereto.

Comparative Example 1, Comparative Example 2 and Example 1

To prepare a rubber composition by combining each component in accordance with the composition shown in Table 1, and to cure each rubber composition to prepare a rubber specimen. The physical properties of the rubber specimens were measured according to ASTM standards, and the results are shown in Table 1 together. Here, the rubber composition of Comparative Example 1 is a rubber composition does not contain silica, the rubber composition of Comparative Example 2 is a rubber composition of the Republic of Korea Patent No. 602895 of the prior art.

Table 1: Composition and Properties of Rubber Composition

division Comparative Example 1 Comparative Example 2 Example 1 Natural rubber 100 100 100 Carbon Black ^{1 )} 50 40 40 Silica ²⁾ - - 10 Silica ³⁾ - 10 Zinc oxide 5 5 5 Stearic acid 2 2 2 Anti-aging agent ⁴⁾ 2 2 2 Wax One One One Process oil One One One brimstone 1.5 1.5 1.5 Accelerator (TBBS) 1.0 1.0 1.0 Longitude (SHORE Hardness) 68 65 70 300% modulus (kg / ㎠) 173 165 179 Tensile Strength (kg / ㎠) 280 220 248 Tensile rate (%) 470 380 405 Exothermic (℃) ⁵⁾ 25.7 22.3 23.3 Tanδ (70 ° C) ⁶⁾ 0.124 0.107 0.101 PICO wear (loss, g) ⁷⁾ 0.022 0.030 0.021 DIN wear (loss) (g) ⁷⁾ 0.075 0.085 0.062

Note: 1) Carbon black with iodine adsorption 150mg / g and DBP oil absorption 140ml / mg

2) Silica with BET 200m ² / g, ASD (D ₅₀ ) 6.5, CTAB 195m ² / g

3) Silica with BET 175m ² / g, ASD (D ₅₀ ) 7.5, CTAB 150m ² / g

4) RD: polymerized 2,2,4-trimethyl-1,2-dihydroquinoline (Kumho Petrochemical)

5) The exothermic performance shows better performance with lower rising temperature.

6) The lower the Tanδ (70 ℃), the better the rolling resistance.

7) The abrasion performance was measured by PICO and DIN abrasion tester, and the smaller the loss, the better.

The durability test (ECER-54), rolling resistance test and actual vehicle results of the 12R22.5 16PR standard tire having a tread part made of the rubber compositions of Example 1 and Comparative Example 1 are shown in Table 2 below.

Table 2: Tire Performance Results

Exam Content Comparative Example 1 Example 1 Durability (driving time) 64 hours 38 minutes 65 hours 22 minutes Rolling resistance (N) 147 140 Actual Vehicle Results (Relative Index) 100 103

      * Durability shows better performance with longer driving time.

      * Rotational resistance shows better performance with smaller applied force (N).

      * Actual vehicle results are better with larger relative index.

As shown in Table 1 and Table 2, the tire tread rubber composition of the present invention is excellent in wear performance, heat generation performance and rotational resistance performance, when applying the tire tread rubber composition of the present invention, the tire durability and rolling resistance It can improve performance.

Claims (1)

With respect to 100 parts by weight of raw material rubber, BET is 190-210 m ² / g, 5-15 parts by weight of silica having an average particle size distribution of 6.0-7.0 and iodine adsorption value is 135-150 mg / g, and DBP oil absorption 120-140 A tire tread rubber composition comprising 35 to 50 parts by weight of carbon black, which is ml / mg.