KR20050050396A - Tread compound for pcr improved abrasion resistance, and tire for pcr using the same - Google Patents

Abstract

The present invention relates to a tread rubber composition for a passenger car and a tire for a passenger car using the same. More specifically, a rubber composition for a passenger car having improved abrasion resistance by adding a mixture of two kinds of carbon blacks having completely different characteristics and configurations at a suitable ratio. And it relates to a tire for a passenger car manufactured using the rubber composition.

In the present invention, the DBP absorption value of 100-130ml / 100g as a reinforcing agent for 100phr of raw material rubber is 15-60phr of carbon black having 70-90m 2 / g of CTAB, and 70-90ml / 100g of DBP absorption value of CTAB. A tread rubber composition for a passenger car containing 15 to 60 phr of carbon black having a 130 to 160 m 2 / g and 20 to 45 phr of process oil is provided.

Description

Tread Compound for PCR Improved Abrasion Resistance, and Tire for PCR Using the same}

The present invention relates to a tread rubber composition for a passenger car and a tire for a passenger car using the same. More specifically, a rubber composition for a passenger car having improved abrasion resistance by adding a mixture of two kinds of carbon blacks having completely different characteristics and configurations at a suitable ratio. And it relates to a tire for a passenger car manufactured using the rubber composition.

In recent years, the performance of a tire for a passenger car has changed a lot in the function of the tire according to the high speed and high performance of the vehicle, and consumers' interest in the vehicle, as well as the common sense and interest in the tire that is directly connected to property and life, have increased the demand level. It is diversified and advanced, and the performance of the tire has been remarkably improved to cope with this.

In particular, durability has been significantly improved, and the key to how long it can be used without being worn out by the destruction of tires before wear, which is the standard of durability, has become a key factor. It is necessary to reduce the environmental pollution caused by rubber powder as it does not wear out in endurance.

The tread thickness of a conventional tire is determined by the depth of the groove, or skid depth, stamped on the tire tread surface, which is generally 12 mm to 14 mm. Thus, tires are designed to have a durability of 5 years at this level (typically 10 km), so that the tread rubber can be dissolved styrene rubber (S-SBR) or emulsion styrene rubber (S-SBR). It consists of reinforcement of small particles of highly aggregated carbon black in rubber (E-SBR), and it is generally composed of adding butadiene rubber (BR) to improve wear performance. For this reason, in order to add a large amount of carbon black while maintaining processability, an excessive amount of process oil may be used, and a vinyl content of rubber may be controlled.

Thus, the addition of carbon black of the same composition to the conventional tread rubber composition for passenger cars has a problem in that when the excess carbon black is added, the difficulty of dispersion occurs, the wear is not uniform and easily broken, and the wear performance is worse. Therefore, it is necessary to develop an eco-friendly tire that contains a large amount of carbon black and induces uniform dispersion to reduce fuel efficiency and rubber dust by reducing tire weight by reducing skid depth due to breakthrough wear performance. It is true.

The present inventors have continuously conducted research to solve the above problems and add two kinds of carbon blacks, which are completely different in particle distribution and aggregate structure, as a reinforcing agent to a rubber for a passenger car, which is generally used in a suitable ratio. As a result, the rubber is uniformly distributed while maintaining a minimum distance between the carbon black components, and the free space between the carbon black components is minimized to maximize the strength, and the carbon black has excellent abrasion resistance characteristics due to even dispersion induction and uniformity. The present invention was completed by finding out that a tread rubber composition for a passenger car can be prepared.

Accordingly, an object of the present invention is to provide a tread rubber composition for passenger cars having improved wear resistance.

Still another object of the present invention is to provide a tire manufactured using the rubber composition.

In general, the tread rubber composition for passenger cars uses a large amount of carbon black and process oil in synthetic rubber to increase reinforcement and increase wear characteristics, and carbon black used as a reinforcing agent for tires has been used until now. It is the most excellent reinforcing material among the reinforcing agents, and has a kind capable of exhibiting various performances in terms of function.

Recently, the technology of using carbon black with excellent reinforcement and filler to increase the braking property by minimizing the volume of rubber and increasing the braking property and the technology of using the entire reinforcing filler as silica have been developed. The technology used for the tire tread stability has been developed, but the situation is required to supplement in terms of wear.

Further increase in carbon black is theoretically impossible, because the amount of carbon black and carbon black is determined to be the optimum amount of additives, which maintains the minimum distance in the rubber and has a uniform distribution, especially in the same particles and the same aggregate. In this case, the spacing between the particle constituents is non-uniform, so in order to maintain the minimum particle spacing, there is a large amount of space in other parts, thus increasing the strength and making it difficult to improve wear.

Therefore, it is necessary to maximize the reinforcing effect by adding a larger amount of carbon black and keeping the gap between the carbon blacks to a minimum and minimizing the free space. For this reason, in general, S-SBR or E -Small particles with high reinforcement, DBP absorbance with high coagulation, 100-120ml / 100g, CTAB 115-140 A tread rubber composition for a passenger car was prepared using 70 to 90 phr of carbon black having m 2 / g and 20 to 35 phr of process oil.

In contrast, in the present invention, a tread rubber composition for a passenger car prepared by mixing carbon black having different characteristics with a generally used tread rubber at a suitable ratio, that is, DBP absorber 100 to 130 ml / 100 g as a reinforcing agent for 100 phr of raw rubber. 15 to 60 phr of carbon black having CTAB of 70 to 90 m 2 / g, 70 to 90 ml / 100 g of DBP absorber, and 15 to 60 phr of carbon black having 130 to 160 m 2 / g of CTAB and 20 to 45 phr of process oil. Provided is a tread rubber composition for a passenger car.

The DBP absorption value is a volume of dibutyl phthalate oil that can be adsorbed to 100 g of carbon black, which means that the higher the value thereof, the more the carbon black structure is developed, and CTAB (Cetyl Trimethylammonium Bromide) measures the specific surface area of carbon black. The larger this value is, the larger the carbon black, that is, the larger the specific surface area.

The raw material rubber used in the rubber composition according to the present invention may be a dissolved styrene rubber (S-SBR), an emulsified styrene rubber (E-SBR) or a mixed rubber of styrene rubber and butadiene rubber (SBR / BR).

The amount of carbon black used in the rubber composition according to the present invention may be used in the above content range, but more preferably, the DBP absorption value is 100 to 130 ml / 100 g and CTAB is 70 to 90 m 2 / g based on 100 phr of raw rubber. 15 to 50 phr of black is mixed first with raw rubber, and 30 to 60 phr of carbon black with DBP absorption of 70 to 90 ml / 100 g and 130 to 160 m 2 / g CTAB is further mixed to induce uniform dispersion and wear characteristics. And the strength is improved. In addition, the reinforcing effect and fracture resistance of the carbon black in the rubber composition are used to induce the carbon black particle aggregates to be uniformly distributed in the rubber composition at a minimum interval and to improve the processability.

Alternatively, 30 to 60 phr of carbon black having a DBP absorption value of 100 to 130 ml / 100 g and a CTAB of 70 to 90 m 2 / g is first mixed with the raw material rubber, and the DBP absorption value is 70 to 90 ml / 100 g and the CTAB is 130 It is preferable to further mix 15 to 45 phr of carbon black of ˜160 m 2 / g. For tires manufactured using the tread rubber composition for passenger cars according to the present invention, the skid depth of the tire is increased to 8 to 10 mm at the same wear level. By reducing, the skid depth of the conventional tire 12-12 mm can be reduced by about 30%.

Other components included in the tread rubber composition for passenger cars according to the present invention, for example, zinc oxide, stearic acid, anti-aging agents, etc. are additives of known tread rubber compositions for passenger cars, each of which is suitably selected according to the range of known addition amount. It is enough to carry out by, so detailed description thereof will be omitted.

Hereinafter, the content of the present invention will be described in detail through Examples and Comparative Examples. However, the following examples are intended to illustrate the present invention in more detail, and the scope of the present invention is not intended to be limited thereto.

<Example 1>

As the compounding ratio shown in Table 1, 26 phr of carbon black (carbon black A) having a DBP absorbance of 125 ml / 100g, CTAB of 76 m 2 / g, and 86 ml of DBP absorbance of 100 phr of E-SBR as raw material rubber. 100 grams, 50 phr of carbon black (carbon black B) with CTAB of 152 m2 / g, process oil 36 phr, zinc oxide 4 phr, stearic acid 1.5 phr, antioxidant 3.0 phr, sulfur 1.8 phr, benzothiazolesulfenamide (CZ) 1.3 phr To prepare a tread rubber composition for passenger cars by mixing 0.3 phr of diphenylguanidine (DPG) and 2.0 phr of phenolic resin, the carbon black A was first mixed with E-SBR and the carbon black B was further mixed. It was.

<Example 2>

 55 phr of carbon black (carbon black A) with DBP absorbance of 125 ml / 100g, CTAB of 76 m2 / g, carbon black (carbon black B) with DBP absorption of 86 ml / 100g and 152 m2 / g of CTAB A tread rubber composition for a passenger car was prepared under the same conditions as in Example 1 except adding 25 phr.

Comparative Example

Tread rubber composition for passenger cars under the same conditions as in Example 1, except that 75 phr of carbon black (carbon black C) having a DBP absorption value of 114 ml / 100 g and a CTAB of 92 m 2 / g was added as carbon black. Was prepared.

<Table 1> Compounding ratio of Example and Comparative Example (unit: phr)

division Example 1 Example 2 Comparative example E-SBR 100 100 100 Carbon black A 26 55 - Carbon black B 50 25 - Carbon black C - - 75 Process oil 36 36 36 Zinc oxide 4 4 4 Stearic acid 1.5 1.5 1.5 Anti-aging 3.0 3.0 3.0 brimstone 1.8 1.8 1.8 Benzothiazolesulfenamide (CZ) 1.3 1.3 1.3 DPG 0.3 0.3 0.3 Phenolic Resin 2.0 2.0 2.0

<Test Example 1>

The rubber composition prepared in Examples 1 to 2 and Comparative Example was vulcanized at 160 ° C. for 15 minutes to prepare a tensile test specimen, and then the modulus, tensile strength, elongation, and picomat performance were measured according to ASTM standards. It is shown in Table 2 below.

<Table 2> Measurement Results of Properties and Wear

division Example 1 Example 2 Comparative example 300% modulus (kgf / ㎠) 135 120 95 Tensile strength (kgf / ㎠) 194 211 175 % Elongation 405 445 475 Picowear (g) 0.165 0.19 0.28

As shown in Table 2, the tread rubber composition for passenger cars according to the present invention can be seen that the physical properties and wear resistance characteristics such as 300% modulus, tensile strength, etc. in the conventional rubber composition is significantly improved.

<Test Example 2>

The skid depths of the tires manufactured by applying the rubber compositions prepared in Examples 1 to 2 and Comparative Examples are shown in Table 3 below.

<Table 3> Tire skid depth measurement results

division Example 1 Example 2 Comparative example Skid depth (mm) 9 9 13

       As shown in Table 3, the tread rubber composition for passenger cars according to the present invention can be seen as a low fuel consumption and environmentally friendly rubber composition by reducing the skid depth to 2/3 level compared to the conventional rubber composition.

According to the rubber composition according to the present invention, it is possible to provide a tread rubber composition for passenger cars having improved durability and wear resistance by adding two different kinds of carbon black as a reinforcing agent in a suitable ratio.

In addition, as the skid depth of the tire manufactured by using the rubber composition according to the present invention is reduced, the durability performance is greatly improved, and the wear ratio is improved by one-third, thereby reducing rubber dust to two-thirds. Can provide.

Claims (5)

15 to 60 phr of carbon black having a DBP absorption of 100 to 130 ml / 100 g, CTAB of 70 to 90 m 2 / g, 70 to 90 ml / 100 g of DBP absorption, and 130 to CTAB for 100 phr of raw rubber. A tread rubber composition for a passenger car comprising 15 to 60 phr of carbon black having 160 m 2 / g and 20 to 45 phr of process oil. The method of claim 1, The raw material rubber is a tread rubber composition for passenger cars, characterized in that the melted styrene rubber (S-SBR), emulsified styrene rubber (E-SBR) or a mixed rubber (SBR / BR) of styrene rubber and butadiene rubber. The method of claim 1, 15 to 50 phr of carbon black with DBP absorption of 100 to 130 ml / 100g, 70 to 90 m 2 / g CTAB, and carbon black of 130 to 160 m 2 / g with DBP absorption of 70 to 90 ml / 100 g Tread rubber composition for passenger cars, characterized in that it contains 30 to 60 phr. The method of claim 1, 30-60 phr of carbon black with DBP absorption value of 100-130 ml / 100g, CTAB of 70-90 m 2 / g and carbon black with DBP absorption of 70-90 ml / 100g and CTAB of 130-160 m 2 / g Tread rubber composition for passenger cars, characterized in that it contains 15 to 45 phr. A tire for a passenger car manufactured by lowering the skid depth of the tread to 8 to 10 mm using the rubber composition for passenger cars according to any one of claims 1 to 4.