KR102471245B1 - Rubber Composition for Tire Treads and Heavy Duty Tire Comprising the Same - Google Patents

Abstract

The present invention relates to a rubber composition for tire tread comprising 100 parts by weight of raw rubber, 40 to 60 parts by weight of carbon black, and 5 to 20 parts by weight of titanium dioxide, and a high-load tire including the same.

Description

Rubber composition for tire treads and heavy duty tires containing the same {Rubber Composition for Tire Treads and Heavy Duty Tire Comprising the Same}

The present invention is a rubber composition for tire treads suitable for use as a high-load tire of heavy-duty vehicles such as trucks and buses, which has excellent wet grip performance and abrasion resistance by adding titanium dioxide having excellent hydrophilicity as a reinforcing filler, and comprising the same It is about heavy duty tires.

The composition of the conventional rubber composition constituting the tire tread for truck/bus uses natural rubber with high molecular weight and strong elasticity as raw material rubber to secure durability that can withstand heavy loads, and carbon black with low heat generation as a reinforcing filler. has been generally used, and in addition, a technique of adding a small amount of silica in addition to the existing carbon black-based reinforcing agent has been utilized to improve chip-cutting performance.

In addition, a technique of additionally using synthetic rubber to natural rubber generally used in rubber compositions for tire treads for trucks/buses is disclosed in order to improve wear resistance and the like beyond the design of rubber compositions focusing on durability.

In recent years, the importance of rolling resistance and wet grip has been increasing in truck/bus tires, centering on advanced markets, and a technology for improving fuel efficiency and wet grip performance by using silica together with existing carbon black as a reinforcing agent has been disclosed.

However, when replacing some of the existing carbon black as a reinforcing agent with silica, there is a disadvantage in that the wear resistance of the tread is lowered, so there is a limit to the application of the silica application technology to truck/bus tires.

In addition, in order to improve wet grip performance, rubber with increased vinyl content in the structure constituting butadiene in styrene-butadiene rubber (SBR) and solution polymerization styrene-butadiene rubber (SSBR) with high styrene content are used individually or in combination. and use it

However, this method is limited in the amount used in the tread composition for trucks/buses, in which 40 to 50 parts by weight or more of natural rubber with high molecular weight and strong elasticity should be included in 100 parts by weight of raw rubber to secure durability that can withstand heavy loads. There is also a limit to improving wet grip performance.

Accordingly, there is a need to develop a technology capable of improving low fuel consumption performance, rolling resistance, and wet grip performance of tires for heavy loads such as truck and bus tires without deterioration in durability and abrasion resistance.

Republic of Korea Patent Registration No. 1160234 (2012.06.26) Republic of Korea Patent Publication No. 2020-0079773 (2020.07.06)

The present invention is to solve the above problems, and to improve low fuel consumption performance and wet grip performance, titanium dioxide is used instead of silica, which has been mainly used in the past, as a reinforcing agent to maintain low fuel consumption performance, and wet grip performance is maintained according to the strong hydrophilicity of titanium dioxide. An object of the present invention is to provide a rubber composition for tire treads capable of further improving grip performance.

An object of the present invention is to provide a rubber composition for a tire tread of a high-load tire capable of improving low fuel consumption performance and wet grip performance without maintaining or deteriorating the wear resistance of the high-load tire.

A high-load tire with improved rolling resistance and wet grip performance while maintaining good abrasion resistance as a heavy-duty tire by solving the problem of deterioration in abrasion resistance of reinforcing fillers added to improve rolling resistance and wet grip performance in general tires. It is an object to provide a rubber composition for tread.

An object of the present invention is to improve wet grip performance, low fuel consumption performance, and rolling resistance, which are physical properties in a trade-off relationship with abrasion resistance, without maintaining or deteriorating abrasion resistance, which is essentially required for high-load tires.

The rubber composition for tire tread according to the present invention for solving the above problems is

100 parts by weight of raw rubber, 40 to 60 parts by weight of carbon black, and 5 to 20 parts by weight of titanium dioxide.

In the present invention, the titanium dioxide may have a BET specific surface area of 10 to 200 m 2 /g.

In the present invention, the raw material rubber may include 40 to 100 parts by weight of natural rubber and 0 to 60 parts by weight of synthetic rubber.

In the present invention, the carbon black may have an iodine adsorption amount of 103 to 1000 mg/g and a nitrogen adsorption specific surface area (N ₂ SA) of 118 to 1000 m 2 /g.

In the present invention, the carbon black may have a DBP oil absorption of 105 to 495 mg/g and a BET specific surface area of 100 to 1000 m 2 /g.

The present invention also provides a tire comprising the above-described rubber composition for tire tread.

The tire according to the present invention may be a truck tire or a bus tire.

According to the present invention, wet grip performance, rolling resistance, and low fuel consumption performance, which are physical properties in a trade-off relationship, are simultaneously improved while satisfying durability and abrasion resistance characteristics required for high-load tires.

According to the present invention, when silica is added to improve wet grip performance of a tire, it is possible to improve wet grip performance while preventing deterioration in abrasion resistance and durability, which are fatal to high-load tires.

In particular, compared to the addition of the same amount of silica as a reinforcing filler, the wet grip performance improvement effect is large, and the wet grip performance is improved while preventing the deterioration of the wear resistance performance.

Hereinafter, each configuration of the present invention will be described in more detail so that those skilled in the art can easily practice it, but this is only one example, and the scope of the present invention is Not limited.

In order to improve low fuel consumption and wet grip performance, which have recently become increasingly important, silica is being used along with carbon black as a reinforcing filler. There was a disadvantage that the wear resistance performance, which is most important in

Accordingly, in order to maintain wear resistance essential for high-load tires, the amount of silica used is limited, and thus there is a limit to the application of a technology for improving wet grip through the application of silica to truck/bus tires.

Accordingly, the present invention intends to provide a tread rubber composition that uses titanium dioxide, which has stronger hydrophilicity than silica, to further improve wet grip performance even when using the same amount by replacing silica, and a truck/bus tire using the same.

Specifically, the rubber composition for a tire tread of a high-load tire according to the present invention includes 100 parts by weight of raw rubber, 40 to 60 parts by weight of carbon black, and 5 to 20 parts by weight of titanium dioxide.

Hereinafter, the rubber composition for tires will be described in detail.

(1) raw rubber

In the rubber composition, the raw rubber may be any one selected from the group consisting of natural rubber, synthetic rubber, and combinations thereof.

The natural rubber has excellent tensile strength and abrasion resistance, and can be used without particular limitation as long as it is commonly used in tire rubber compositions. Specifically, the natural rubber may be general natural rubber or modified natural rubber.

As the general natural rubber, any known natural rubber may be used, and the country of origin is not limited. The natural rubber mainly includes cis-1,4-polyisoprene, but may also include trans-1,4-polyisoprene according to required properties. Therefore, in addition to natural rubber containing cis-1,4-polyisoprene as a main component, natural rubber containing trans-1,4-isoprene as a main component, such as balata, a kind of rubber of the Sapotaceae family from South America, Rubber may also be included.

The modified natural rubber refers to a product obtained by modifying or refining the general natural rubber. For example, examples of the modified natural rubber include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber.

The synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, polybutadiene rubber, polyisoprene rubber, butyl rubber (BR), chlorosulfonated polyethylene rubber, epichlorohydrin Rubber, fluorine rubber, silicone rubber, nitrile rubber, hydrogenated nitrile rubber, nitrile butadiene rubber (NBR), modified nitrile butadiene rubber, chlorinated polyethylene rubber, styrene ethylene butylene styrene (SEBS) rubber, ethylene propylene rubber, ethylene propylene Diene (EPDM) rubber, hypalon rubber, chloroprene rubber, ethylene vinyl acetate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromo methyl styrene butyl rubber, maleic acid styrene butadiene rubber, carboxylic acid styrene butadiene rubber , from the group consisting of epoxy isoprene rubber, maleic acid ethylene propylene rubber, carboxylic acid nitrile butadiene rubber, brominated polyisobutyl isoprene-co-paramethyl styrene (BIMS) and combinations thereof It may be any one selected.

Meanwhile, the raw material rubber may preferably include 40 to 100 parts by weight of natural rubber and 0 to 60 parts by weight of synthetic rubber.

The present invention relates to a rubber composition for tire tread included in the tread of a tire for heavy loads such as a truck tire or a bus tire, which contains natural rubber to satisfy the durability and abrasion resistance essential to high load tires. it is desirable

Therefore, when the natural rubber is included in a smaller amount than the above content, the durability and abrasion resistance of the tire are lowered, and there may be a problem that it is not suitable for use in a tire for high load such as a truck tire.

(2) reinforcing filler

In the present invention, carbon black and titanium dioxide were used as reinforcing fillers.

As in the present invention, high-load tires such as truck tires and bus tires use natural rubber with high molecular weight and strong elasticity as raw material rubber as a concept to secure durability that can withstand heavy loads, and carbon black with low heat generation as a reinforcing agent. method of injecting was generally used.

In the case of including only carbon black as the reinforcing filler, low fuel consumption performance and wet grip performance were somewhat deteriorated. There was a problem that was not suitable for medium-sized tires.

The present invention is characterized by including titanium dioxide as a component that improves wet grip performance and suppresses a decrease in abrasion resistance, which can be obtained when silica is added.

At this time, the titanium dioxide is added together with the carbon black. Specifically, 40 to 60 parts by weight of carbon black and 5 to 20 parts by weight of titanium dioxide may be included based on 100 parts by weight of raw rubber.

More preferably, 45 to 55 parts by weight of the carbon black may be added.

If carbon black is added in excess of the above content, it may be difficult to secure durability suitable for use in high-load tires. There is a problem of insufficient wear performance.

In addition, the carbon black may have an iodine adsorption amount of 103 to 1000 mg/g, a nitrogen adsorption specific surface area (N ₂ SA) of 118 to 1000 m 2 /g, and DBP (n-dibutyl phthalate) The oil absorption may be 105 to 495 mg/g and the BET specific surface area may be 100 to 1000 m 2 /g, but the present invention is not limited thereto.

More preferably, the iodine adsorption amount of the carbon black may be 110 to 200 mg/g. If the iodine adsorption amount is smaller than the above range, mixing processability may be poor, and if it is higher than the above range, it may be difficult to secure tread wear performance.

In addition, the nitrogen adsorption specific surface area of the carbon black may be more preferably 120 to 200 m 2 /g. When the nitrogen adsorption specific surface area of carbon black is smaller than the above range, there may be a problem that the reinforcing performance as a reinforcing filler may be disadvantageous, and when it is larger than the above range, there may be a problem that the processability of the rubber composition is lowered. .

The amount of n-dibutyl phthalate (DBP) oil absorption of the carbon black is more preferably 110 to 220 mg/g, and when it has a value lower than the above range, the reinforcing performance as a reinforcing filler may be disadvantageous. There is a problem, and when it has a value higher than the above range, there is a problem that the processability of the rubber composition may be reduced.

The BET specific surface area of the carbon black is more preferably 120 to 250 m 2 / g, and when it has a value lower than the above range, there is a problem of heat generation and poor durability performance, and a value higher than the above range In the case of having, there is a problem of poor workability.

Representative examples of the carbon black are N110, N121, N134, N220, N231, N234, N242, N293, N299, S315, N326, N330, N332, N339, N343, N347, N351, N358, N375, N539, N550, N582 , N630, N642, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990 or N991.

On the other hand, in the present invention, the titanium dioxide has stronger hydrophilicity than silica and has excellent wet grip performance even when a small amount is added, thereby providing a tire for high loads with improved wet grip performance without deterioration in abrasion resistance. have.

More preferably, the titanium dioxide may be included in an amount of 7 to 20 parts by weight based on 100 parts by weight of the raw rubber.

When titanium dioxide is added in excess of the above content, there is a problem that the dispersibility in the rubber composition may be poor, and when titanium dioxide is added in a small amount than the above content, there is a problem that the effect of improving wet grip performance is insignificant. have.

Titanium dioxide is titanium oxide and has a white particle form. In the present invention, titanium dioxide having a BET specific surface area of 10 to 200 m 2 /g can be used. More preferably, 20 to 150 m 2 / g can be used.

When the BET specific surface area of the titanium dioxide satisfies the above range, the dispersibility of the titanium dioxide in the rubber composition can be improved.

However, this is only one example, and various modifications are possible within the scope of achieving the object of the present invention.

(3) Other additives

The rubber composition may optionally further contain various additives such as additional vulcanization agents, vulcanization accelerators, vulcanization accelerators, anti-aging agents, softeners, or tackifiers. Any of the various additives may be used as long as they are commonly used in the field to which the present invention belongs, and their contents are not particularly limited as they depend on the compounding ratio used in conventional rubber compositions for tire treads.

As the vulcanizing agent, a sulfur-based vulcanizing agent, an organic peroxide, a resin vulcanizing agent, and a metal oxide such as magnesium oxide may be used.

The sulfur-based vulcanizing agent is an inorganic vulcanizing agent such as powdered sulfur (S), insoluble sulfur (S), precipitated sulfur (S), colloidal sulfur, tetramethylthiuram disulfide (TMTD), tetraethyl Organic vulcanizers such as tetraethylthiuram disulfide (TETD) and dithiodimorpholine may be used. As the sulfur vulcanizing agent, elemental sulfur or a vulcanizing agent that produces sulfur, for example, amine disulfide, polymeric sulfur, etc. may be used.

The organic peroxide is benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, 2,5-dimethyl-2,5-di( t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane-3, 1 ,3-bis(t-butylperoxypropyl)benzene, di-t-butylperoxy-diisopropylbenzene, t-butylperoxybenzene, 2,4-dichlorobenzoylperoxide, 1,1-dibutylper Any one selected from the group consisting of oxy-3,3,5-trimethylsiloxane, n-butyl-4,4-di-t-butylperoxyvalerate, and combinations thereof may be used.

The vulcanizing agent is preferably included in an amount of 0.5 to 5.0 parts by weight based on 100 parts by weight of the raw rubber in that the raw rubber is less sensitive to heat and chemically stable as a proper vulcanization effect.

The vulcanization accelerator refers to an accelerator that accelerates the vulcanization rate or promotes a delaying action in the initial vulcanization step.

The vulcanization accelerators include sulfenamide-based, thiazole-based, thiuram-based, thiourea-based, guanidine-based, dithiocarbamic acid-based, aldehyde-amine-based, aldehyde-ammonia-based, imidazoline-based, xanthate-based and these Any one selected from the group consisting of combinations may be used.

Examples of the sulfenamide-based vulcanization accelerator include N-cyclohexyl-2-benzothiazylsulfenamide (CBS), N-tert-butyl-2-benzothiazylsulfenamide (TBBS), N,N-dicyclohexyl Any one selected from the group consisting of -2-benzothiazylsulfenamide, N-oxydiethylene-2-benzothiazylsulfenamide, N,N-diisopropyl-2-benzothiazolesulfenamide, and combinations thereof A sulfenamide-based compound of can be used.

Examples of the thiazole-based vulcanization accelerator include 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), sodium salt of 2-mercaptobenzothiazole, and zinc salt of 2-mercaptobenzothiazole. , copper salt of 2-mercaptobenzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-di Any one thiazole-based compound selected from the group consisting of ethyl-4-morpholinothio)benzothiazole and combinations thereof may be used.

Examples of the thiuram-based vulcanization accelerator include tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram disulfide, dipentamethylenethiuram monosulfide, dipentamethylene Any one thiuram-based compound selected from the group consisting of thiuram tetrasulfide, dipentamethylenethiuram hexasulfide, tetrabutylthiuram disulfide, pentamethylenethiuramtetrasulfide, and combinations thereof may be used.

The thiourea-based vulcanization accelerator is, for example, any one thiourea-based selected from the group consisting of thiacarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diortotolylthiourea, and combinations thereof compound can be used.

As the guanidine-based vulcanization accelerator, for example, any one guanidine-based compound selected from the group consisting of diphenylguanidine, diortolylguanidine, triphenylguanidine, orthotolylbiguanide, diphenylguanidine phthalate, and combinations thereof may be used. can

Examples of the dithiocarbamic acid-based vulcanization accelerator include zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, and zinc dibutyldithiocarbamate. , diamyldithiocarbamate zinc, dipropyldithiocarbamate zinc, dibenzyldithiocarbamate zinc, hexadecylisopropyldithiocarbamate zinc, octadecylisopropyldithiocarbamate zinc, pentamethylene dithiocarbamate Complex salts of zinc bamate and piperidine, sodium dimethyldithiocarbamate, sodium diethyldithiocarbamate, piperidine pentamethylenedithiocarbamate, selenium dimethyldithiocarbamate, tellurium diethyldithiocarbamate, Any one dithiocarbamate-based compound selected from the group consisting of cadmium diamyldithiocarbamate and combinations thereof may be used.

The aldehyde-amine-based or aldehyde-ammonia-based vulcanization accelerator is, for example, an aldehyde selected from the group consisting of acetaldehyde-aniline reactants, butyraldehyde-aniline condensates, hexamethylenetetramine, acetaldehyde-ammonia reactants, and combinations thereof - Amine-based or aldehyde-ammonia-based compounds may be used.

As the imidazoline-based vulcanization accelerator, for example, an imidazoline-based compound such as 2-mercaptoimidazoline may be used, and as the xanthate-based vulcanization accelerator, for example, a xanthate-based compound such as zinc dibutylxanthogenate may be used. compound can be used.

The vulcanization accelerator may be included in an amount of 0.5 to 5.0 parts by weight based on 100 parts by weight of the raw rubber in order to maximize productivity and rubber properties by accelerating the vulcanization rate.

The vulcanization accelerator is a compounding agent used in combination with the vulcanization accelerator to completely promote the effect, and any one selected from the group consisting of inorganic vulcanization accelerators, organic vulcanization accelerators, and combinations thereof may be used. .

As the inorganic vulcanization accelerator, any one selected from the group consisting of zinc oxide (ZnO), zinc carbonate, magnesium oxide (MgO), lead oxide, potassium hydroxide, and combinations thereof can be used. have.

The organic vulcanization accelerator is selected from the group consisting of stearic acid, zinc stearate, palmitic acid, linoleic acid, oleic acid, lauric acid, dibutyl ammonium oleate, derivatives thereof, and combinations thereof Any one of them can be used.

In particular, as the vulcanization accelerator, the zinc oxide and the stearic acid may be used together. In this case, the zinc oxide is dissolved in the stearic acid to form an effective complex with the vulcanization accelerator, thereby removing advantageous sulfur during the vulcanization reaction. By making it, it facilitates the crosslinking reaction of rubber.

When the zinc oxide and the stearic acid are used together, they may be used in amounts of 1 to 5 parts by weight and 0.5 to 3 parts by weight, respectively, based on 100 parts by weight of the raw rubber, in order to serve as an appropriate vulcanization accelerator. When the contents of the zinc oxide and the stearic acid are less than the above range, the vulcanization rate is slow and productivity may decrease. When the content exceeds the above range, a scorch phenomenon may occur and physical properties may be deteriorated.

The softener is added to a rubber composition to facilitate processing by imparting plasticity to rubber or to reduce the hardness of vulcanized rubber, and refers to oils and other materials used in rubber compounding or rubber manufacturing. The softening agent refers to processing oil or oils included in other rubber compositions. As the softening agent, any one selected from the group consisting of petroleum oil, vegetable oil, and combinations thereof may be used, but the present invention is not limited thereto.

As the petroleum-based oil, any one selected from the group consisting of paraffinic oil, naphthenic oil, aromatic oil, and combinations thereof may be used.

Representative examples of the paraffinic oil include P-1, P-2, P-3, P-4, P-5, and P-6 of Michang Oil Co., Ltd., and a representative example of the naphthenic oil is Michang Oil. and N-1, N-2, and N-3 of Michang Oil Co., Ltd., and A-2 and A-3 of Michang Oil Co., Ltd. as representative examples of the aromatic oil.

However, with the recent rise in environmental awareness, when the content of polycyclic aromatic hydrocarbons (hereinafter referred to as PAHs) contained in the aromatic oil is 3% by weight or more, it is known that the possibility of causing cancer is high, TDAE ( Treated distillate aromatic extract (MES) oil, MES (mild extraction solvate) oil, RAE (residual aromatic extract) oil, or heavy naphthenic oil may be preferably used.

In particular, the oil used as the softener has a total content of PAHs of 3% by weight or less, a kinematic viscosity of 95 or more (210 ° F SUS), an aromatic component in the softener of 15 to 25% by weight, and a naphthenic component with respect to the entire oil. A TDAE oil containing 27 to 37% by weight and 38 to 58% by weight of paraffinic components can be preferably used.

The TDAE oil improves low-temperature characteristics and fuel efficiency of tire treads including the TDAE oil, but also has advantageous properties against environmental factors such as the possibility of PAHs causing cancer.

The plant oils include castor oil, cottonseed oil, linseed oil, canola oil, soybean oil, palm oil, palm oil, peanut oil, pine oil, pine tar, tall oil, corn oil, rice bran oil, safflower oil, sesame oil, olive oil, sunflower oil, palm kernel oil, camellia oil , jojoba oil, macadamia nut oil, safflower oil, tung oil, and any one selected from the group consisting of combinations thereof may be used.

The softener is preferably used in an amount of 1 to 50 parts by weight based on 100 parts by weight of the raw rubber in view of improving processability of the raw rubber.

The antioxidant is an additive used to stop a chain reaction in which a tire is automatically oxidized by oxygen. As the anti-aging agent, any one selected from the group consisting of amine-based, phenol-based, quinoline-based, imidazole-based, carbamic acid metal salts, waxes, and combinations thereof may be appropriately selected and used.

Examples of the amine-based antioxidant include N-phenyl-N'-(1,3-dimethyl)-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N,N'-diaryl-p-phenylenediamine, N-phenyl-N' Any one selected from the group consisting of -cyclohexyl-p-phenylenediamine, N-phenyl-N'-octyl-p-phenylenediamine, and combinations thereof may be used.

The phenolic antioxidants include phenolic 2,2'-methylene-bis(4-methyl-6-tert-butylphenol), 2,2'-isobutylidene-bis(4,6-dimethylphenol), 2 Any one selected from the group consisting of ,6-di-t-butyl-p-cresol and combinations thereof may be used.

As the quinoline-based antioxidant, 2,2,4-trimethyl-1,2-dihydroquinoline and derivatives thereof may be used, specifically 6-ethoxy-2,2,4-trimethyl-1,2-di consisting of hydroquinoline, 6-anilino-2,2,4-trimethyl-1,2-dihydroquinoline, 6-dodecyl-2,2,4-trimethyl-1,2-dihydroquinoline, and combinations thereof. Any one selected from the group can be used.

As the wax, waxy hydrocarbon may be preferably used.

In addition to the anti-aging action, the anti-aging agent should have high solubility in rubber, be low in volatility, be inactive with respect to rubber, and should not inhibit vulcanization, etc., 0.1 to 10 parts by weight of the raw rubber. It may be included in parts by weight.

The rubber composition for a tire may be manufactured through a conventional two-step continuous manufacturing process. That is, during the first step of thermomechanical treatment or kneading at a maximum temperature ranging from 110 to 190 °C, preferably at a high temperature of 130 to 180 °C and the finishing step in which the crosslinking system is mixed, typically less than 110 °C, for example It can be prepared in a suitable mixer using the second step of mechanical treatment at a low temperature of 40 to 100 ° C., but the present invention is not limited thereto.

The rubber composition for tires is not limited to treads (tread caps and tread bases) and may be included in various rubber components constituting a tire. The rubber component may include a sidewall, a sidewall insert, an apex, a chafer, a wire coat or an inner liner. However, in the case of the rubber composition according to the present invention, it is more preferable to use it in the tread of a tire that is highly affected by load and abrasion.

A tire according to another embodiment of the present invention is manufactured using the rubber composition for a tire. As a method for manufacturing a tire using the rubber composition for a tire, any method conventionally used for manufacturing a tire can be applied, and thus a detailed description thereof will be omitted herein.

The tire may be a car tire, a racing tire, an airplane tire, an agricultural machine tire, an off-the-road tire, a truck tire, or a bus tire. In addition, the tire may be a radial tire or a bias tire, preferably a radial tire.

In particular, the present invention is particularly suitable for radial tires, such as truck tires and bus tires, which have a large body weight and are greatly affected by a high load due to a large number of cargo or occupants loaded on the vehicle body, and thus require durability and abrasion resistance. It is desirable to apply

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

[Production Example: Preparation of Rubber Composition]

Rubber compositions for tires according to Examples and Comparative Examples were prepared using the compositions shown in Table 1 below. The preparation of the rubber composition was in accordance with a conventional rubber composition preparation method and is not particularly limited.

division
(unit: parts by weight) Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 natural rubber 100 100 100 100 100 100 Carbon Black ¹⁾ 50 50 45 50 45 50 Silica ²⁾ - 15 15 - - - Titanium Dioxide ³⁾ - - - 15 15 10 coupling agent - 3 3 3 3 3 zinc oxide 4.5 4.5 4.5 4.5 4.5 4.5 stearic acid 3.5 3.5 3.5 3.5 3.5 3.5 brimstone 1.5 1.5 1.5 1.5 1.5 1.5 accelerant 1.2 1.2 1.2 1.2 1.2 1.2

1) Carbon black: iodine adsorption amount 115 mg/g, nitrogen adsorption specific surface area 136 ㎡/g, DBP oil absorption amount 105 mg/g

2) Silica: Precipitated silica with CTAB 160 m/g, BET 175 m/g

3) Titanium dioxide: titanium dioxide with a BET value of 20 to 150 m/g

[Experimental Example: Measurement of physical properties of the prepared rubber composition]

The physical properties of the prepared rubber composition were measured according to ASTM regulations, and the results are shown in Table 2 below.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 Hardness
(Shore A) 66 75 72 76 72 72 300% Modulus (Mpa) 162 180 175 182 176 176 Wear resistance performance index 100 95 90 96 90 98 Low fuel economy performance index 100 102 108 102 109 100 Wet grip performance index 100 110 108 116 112 110

- Tensile properties: Tensile properties: Hardness was measured using a Shore A durometer, and tensile properties were measured using an Instron tester according to the ASTM D412 test method.

- Abrasion resistance, low fuel consumption, and wet grip performance index are index values shown in Example 1 based on 100, and the larger the number, the more advantageous it is.

As shown in Table 2, low fuel consumption performance and wet grip performance were improved when silica and titanium dioxide were used.

As in Example 1 compared to Comparative Example 2 and Example 2 compared to Comparative Example 3, when the same amount of silica was replaced with titanium dioxide, wet grip performance was further improved, and wear resistance and low fuel consumption performance were maintained at similar levels.

In addition, as shown in Example 3 compared to Comparative Example 2, it can be seen that even when a reduced amount of titanium dioxide is applied, the wet grip performance is equally maintained and the trade-off of wear resistance performance can be greatly reduced compared to Comparative Example 1.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

Claims (7)

100 parts by weight of raw rubber, 40 to 60 parts by weight of carbon black, and 5 to 20 parts by weight of titanium dioxide,
The rubber composition for tire tread, characterized in that the BET specific surface area of the titanium dioxide is 20 to 150 m 2 / g.
delete According to claim 1,
The rubber composition for tire treads, wherein the raw rubber comprises 40 to 100 parts by weight of natural rubber and 0 to 60 parts by weight of synthetic rubber.
According to claim 1,
The carbon black has an iodine adsorption amount of 103 to 1000 mg/g and a nitrogen adsorption specific surface area (N ₂ SA) of 118 to 1000 m 2 /g.
According to claim 1,
The carbon black has a DBP oil absorption of 105 to 495 mg/g and a BET specific surface area of 100 to 1000 m 2 / g.
A tire comprising the rubber composition for tire tread according to any one of claims 1 to 5.
According to claim 6,
The tire is characterized in that the tire is a truck tire or a bus tire.