KR101140246B1 - Rubber composition for tire tread and tire manufactured by the same - Google Patents

Abstract

The present invention relates to a rubber composition for a tire tread and a tire manufactured using the same, a tire tread including 100 parts by weight of raw material rubber, 20 to 90 parts by weight of silica, and 3 to 10 parts by weight of a coupling agent represented by the following Chemical Formula 1 It provides a rubber composition for.

[Formula 1]

In Formula 1, the definitions of R ₁ to R ₃ and n are as described in the specification. The rubber composition for tire treads improves low fuel efficiency by using silica as a reinforcing filler and has excellent dispersibility of silica, and uses a coupling agent that does not contain sulfur in the molecular structure to limit the mixing temperature during rubber compounding. It can overcome and reduce the emission of hydrocarbons generated during or after tire production.

Tire, Tread, Rubber, Silica, Reinforcing Filler, Coupling Agent, Hydrocarbon, Alcohol, Alkoxy Group

Description

RUBBER COMPOSITION FOR TIRE TREAD AND TIRE MANUFACTURED BY THE SAME}

The present invention relates to a rubber composition for tire treads and a tire manufactured using the same, and to a rubber composition for tire treads and a tire manufactured using the same, which can reduce the emission of hydrocarbons.

With the recent rise of environmental awareness, regulations related to the global environment have been enacted. In order to cope with this, the industry is trying to secure technology for eco-friendly technology. One of the most important regulations in the automotive industry is the law on carbon dioxide emissions. In addition, the most recent issue of tire regulation is the regulation on tire performance labeling being promoted in Europe and North America, and all tire industries are devoted to developing related technologies.

In order to cope with such regulations, the improvement of low fuel efficiency performance technology is the most urgent matter. Accordingly, research and development of a rubber composition using silica having excellent low fuel efficiency as a rubber filler is being actively conducted. The most important technique in the rubber composition using silica as a rubber filler is to disperse hydrophilic silica in lipophilic rubber, and many techniques for surface modification of silane and silane coupling agent have been recently introduced. There is.

However, the silane coupling agent used to induce dispersion of silica and bonding between silica and rubber reacts with hydroxyl groups on the surface of the silica and alkoxy groups of the silane coupling agent to release alcohol as a by-product. Compared to the rubber composition used as a hydrocarbon emissions are a lot of problems. In addition, since the main silane coupling agent has sulfur inside the molecular structure, there is a problem in that the mixing temperature is limited when rubber is mixed.

It is an object of the present invention to provide a rubber composition for tire treads that uses silica as a reinforcing filler, but also has excellent dispersibility of silica to improve low fuel efficiency and reduce hydrocarbon material emissions.

In order to achieve the above object, the rubber composition for a tire tread according to an embodiment of the present invention comprises 100 parts by weight of the raw material rubber, 20 to 90 parts by weight of silica, and 3 to 10 parts by weight of the coupling agent represented by the following formula (1). .

[Formula 1]

(In the formula 1,

R ₁ to R ₃ is an alkyl group having 1 to 4 carbon atoms,

N is an integer of 3 to 7)

The coupling agent represented by Formula 1 may be 3-glycidoxy propyl dimethyl ethoxy silane.

The tire tread rubber composition may further include 4 to 8 parts by weight of a sulfide-based coupling agent.

The sulfide coupling agent is bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (4-triethoxysilylbutyl) tetrasulfide, bis (3-tri Methoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, bis (4-trimethoxysilylbutyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (2 -Triethoxysilylethyl) trisulfide, bis (4-triethoxysilylbutyl) trisulfide, bis (3-trimethoxysilylpropyl) trisulfide, bis (2-trimethoxysilylethyl) trisulfide, bis (4-trimethoxysilylbutyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide, bis (4-triethoxysilylbutyl) disulfide, bis ( 3-trimethoxysilylpropyl) disulfide, bis (2-trimethoxy Ylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthio Carbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropyl Benzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide and combinations thereof It may be any one selected from the group.

The tire tread rubber composition may further include a vulcanizing agent, and the weight ratio of the sulfide-based coupling agent and the vulcanizing agent may be 4: 1.25 to 8: 1.1.

A tire according to another embodiment of the present invention is manufactured using the rubber composition for the tire tread.

Hereinafter, the present invention will be described in more detail.

Unless stated otherwise in the specification, an "alkyl group" may be a straight or crushed substituted or unsubstituted alkyl group. Herein, "substituted" means that a hydrogen atom has a halogen atom, a hydroxy group, a carboxy group, a nitrile group, an aldehyde group, an epoxy group, an alkyl group, a perfluoroalkyl group, a cycloalkyl group, a heterocycloalkyl group, an allyl group, a benzyl group, an aryl group, hetero It means substituted by any one selected from the group consisting of an aryl group, derivatives thereof and combinations thereof.

The tire tread rubber composition includes 100 parts by weight of raw material rubber, 20 to 90 parts by weight of silica, and 3 to 10 parts by weight of a coupling agent represented by the following Chemical Formula 1.

[Formula 1]

(In Formula 1, R ₁ to R ₃ is an alkyl group having 1 to 4 carbon atoms, n is an integer of 3 to 7)

The raw material rubber is not particularly limited in the present invention, it may be any one selected from the group consisting of natural rubber, synthetic rubber and combinations thereof.

The natural rubber may be a general natural rubber or modified natural rubber.

The general natural rubber may be used as long as it is known as a natural rubber, the country of origin and the like are not limited. The natural rubber contains cis-1,4-polyisoprene as a main agent, but may also include trans-1,4-polyisoprene depending on the required properties. Therefore, the natural rubber includes natural rubber containing cis-1,4-polyisoprene as a main agent, and trans-1,4-isoprene as a main agent, for example, balata, which is a kind of rubber of South American sapotagua. Rubber may also be included.

The modified natural rubber means a modified or refined general natural rubber. For example, the modified natural rubber may include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), hydrogenated natural rubber, and the like.

Synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, nitrile rubber, nitrile butadiene rubber (NBR), modified nitrile butadiene rubber, vinyl benzyl chloride styrene butadiene rubber, maleic acid It may be any one selected from the group consisting of styrene butadiene rubber, carboxylic acid styrene butadiene rubber, carboxylic acid nitrile butadiene rubber, and combinations thereof.

In particular, the raw material rubber is emulsion-polymerized Styrene Butadiene Rubber (hereinafter referred to as "E-SBR"), solution-polymerized Styrene Butadiene Rubber (Solution-polymerized Styrene Butadiene Rubber, "S" -SBR "), butadiene rubber (butadiene rubber," BR ") and any one selected from the group consisting of a combination thereof may be used, but the present invention is not limited thereto.

The E-SBR may have a styrene content of 40 to 50% by weight, a vinyl content of 10 to 20% by weight, and a glass transition temperature (Tg) of -30 to -40 ° C. The E-SBR has a lower glass transition temperature (Tg) and a lower vinyl content than S-SBR, and thus has a disadvantage in braking performance on wet roads, but may advantageously act on rotational resistance and wear performance. The E-SBR may preferably be used having a weight average molecular weight of 800,000 or more.

In addition, the E-SBR may contain 25 to 50 parts by weight of TDAE (Treated Distillate Aromatic Extract) oil per 100 parts by weight of the original rubber elastomer, and preferably may contain 35 to 40 parts by weight. When the E-SBR contains 25 to 50 parts by weight of TDAE oil per 100 parts by weight of the rubber elastomer, it can be expected to increase the flexibility of the E-SBR reduced by the influence of styrene.

The S-SBR may have a styrene content of 20 to 40% by weight, a vinyl content of 40 to 60% by weight, and a glass transition temperature (Tg) of -30 to -20 ° C. In the case of using the S-SBR having the above characteristics, since the hysteresis of the tire tread is increased, braking performance on a dry or wet surface can be improved at the same time.

In addition, the S-SBR may contain 25 to 50 parts by weight of TDAE oil per 100 parts by weight of the original rubber elastomer, preferably 35 to 40 parts by weight. When the S-SBR contains 25 to 50 parts by weight of TDAE oil per 100 parts by weight of the elastomeric elastomer, it is preferable in view of the increased flexibility of S-SBR reduced by the influence of styrene.

In addition, when using a mixture of styrene butadiene rubber and butadiene rubber as the raw material rubber, it may be used consisting of 30 to 90 parts by weight of styrene butadiene rubber and 10 to 90 parts by weight of butadiene rubber, 50 to 80 parts by weight of styrene butadiene rubber and What consists of 20-50 weight part of butadiene rubber can be used preferably.

The tire tread rubber composition may improve the tensile strength of rubber by using silica as a reinforcing filler.

The content of the silica is included in 20 to 90 parts by weight, preferably 30 to 70 parts by weight, and more preferably 40 to 60 parts by weight based on 100 parts by weight of the raw material rubber. When the content of the silica is less than 20 parts by weight, the strength improvement of the rubber may be insufficient and the braking performance of the tire may be reduced, and when the content of the silica exceeds 90 parts by weight, wear performance may be reduced.

The silica may have a nitrogen adsorption specific surface area of 160 to 180 m 2 / g, and a CTAB (cetyl trimethyl ammonium bromide) adsorption specific surface area of 150 to 170 m 2 / g may be used, but the present invention is limited thereto. It doesn't happen. The silica can be used both wet or dry method, and commercially available products may be used Ultrasil 7000GR, Ultrasil VN2 (manufactured by Degussa), Ultrasil VN3 (manufactured by Degussa).

The coupling agent represented by Chemical Formula 1 may reduce the emission of hydrocarbons generated during or after tire manufacture, and may not include sulfur in the molecular structure to overcome the limitation of the mixing temperature during rubber compounding, and at the same time, low fuel consumption. It can improve performance.

That is, in the case of the coupling agent which is generally used, sulfur is contained in the molecular structure with a trialkoxy substituent or dialkoxy substituent. This is because the substituent, such as the alkoxy group, must be present to react with the hydroxy group of the silica to hydrophilize the silica to improve the dispersibility of the silica.

However, the alkoxy group remaining after reacting with the hydroxyl group of the silica continues to react with the hydroxyl group, moisture, or other coupling agent of the silica to produce hydrocarbons such as alcohol even after the tire is manufactured.

On the other hand, the coupling agent represented by Formula 1 can improve the low fuel consumption while reducing hydrocarbon emissions because only one alkoxy is present, and can overcome the limitation of the mixing temperature during rubber compounding by not including sulfur in the molecular structure. Can be.

Specific examples of the coupling agent represented by Formula 1 include 3-glycidoxy propyl dimethyl ethoxy silane, and the 3-glycidoxypropyl dimethylethoxysilane is used. In this case, it is preferable in terms of reducing the emission of hydrocarbons, overcoming the limitation of the mixing temperature when rubber compounding, and the improvement of low fuel consumption characteristics.

The coupling agent represented by Formula 1 may be included in 3 to 10 parts by weight based on 100 parts by weight of the raw material rubber. When the content of the coupling agent represented by the formula (1) is less than 3 parts by weight, the effect of reducing the emission of hydrocarbons, limiting the mixing temperature during rubber compounding and improving the low fuel consumption characteristics is insignificant, and when the content of the coupling agent exceeds 10 parts by weight, the mechanical properties of the rubber compound. There may be a problem that lowers.

The tire tread rubber composition may further include a second coupling agent in addition to the coupling agent represented by Chemical Formula 1.

The second coupling agent may be a sulfide coupling agent, a mercapto coupling agent, a vinyl coupling agent, an amino coupling agent, a glycidoxy clock coupling agent, a nitro coupling agent, a chloro coupling agent, or a combination thereof. It may be any one selected.

The sulfide coupling agent is bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (4-triethoxysilylbutyl) tetrasulfide, bis (3-tri Methoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, bis (4-trimethoxysilylbutyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (2 -Triethoxysilylethyl) trisulfide, bis (4-triethoxysilylbutyl) trisulfide, bis (3-trimethoxysilylpropyl) trisulfide, bis (2-trimethoxysilylethyl) trisulfide, bis (4-trimethoxysilylbutyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide, bis (4-triethoxysilylbutyl) disulfide, bis ( 3-trimethoxysilylpropyl) disulfide, bis (2-trimethoxy Ylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthio Carbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetra sulfide, 3-trimethoxysilylpropyl Benzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide and combinations thereof It may be any one selected from the group.

The mercapto-based coupling agent is 3-mercaptopropyltrimethoxysilane, 3-mercaptotopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptotoethyltriethoxysilane and combinations thereof It may be any one selected from the group consisting of. The vinyl coupling agent may be any one selected from the group consisting of ethoxysilane, vinyltrimethoxysilane, and combinations thereof. The amino-based coupling agent is 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltri It may be any one selected from the group consisting of methoxysilane and combinations thereof.

The glycidoxy clock coupling agent γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane And combinations thereof may be any one selected from the group consisting of. The nitro-based coupling agent may be any one selected from the group consisting of 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and combinations thereof. The chloro-based coupling agent is selected from the group consisting of 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane and combinations thereof It can be any one.

The second coupling agent may be included in an amount of 4 to 8 parts by weight based on 100 parts by weight of the raw material rubber. When the content of the second coupling agent is less than 4 parts by weight, the kneading and extrusion processability of the rubber may be reduced or the rubber strength may be reduced. When the content of the second coupling agent is more than 8 parts by weight, the hydrocarbon emission may increase, and the mixing and extrusion processability of the rubber may be improved. Although the effect is small, the cost increases and it is not economical, and the strength of the rubber can be lowered.

The tire tread rubber composition may optionally further include various additives such as additional vulcanizing agents, vulcanization accelerators, vulcanization accelerators, anti-aging agents, softeners or pressure-sensitive adhesives. The various additives can be used as long as it is commonly used in the field of the present invention, the content thereof is not particularly limited, depending on the compounding ratio used in the conventional tire tread rubber composition.

As the vulcanizing agent, metal oxides such as sulfur vulcanizing agents, organic peroxides, resin vulcanizing agents, and magnesium oxide can be used.

The sulfur-based vulcanizing agents include inorganic vulcanizing agents such as powdered sulfur (S), insoluble sulfur (S), precipitated sulfur (S) and colloidal sulfur, tetramethylthiuram disulfide (TMTD) and tetraethyl. Organic vulcanizing agents such as tetraethyltriuram disulfide (TETD) and dithiodimorpholine can be used. Specifically, as the sulfur vulcanizing agent, a vulcanizing agent which produces elemental sulfur or sulfur, for example, amine disulfide, polymer sulfur, or the like can be used.

The organic peroxide may be 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, 1,3- Bis (t-butylperoxypropyl) benzene, di-t-butylperoxy-diisopropylbenzene, t-butylperoxybenzene, 2,4-dichlorobenzoyl peroxide, 1,1-dibutylperoxy-3 Any one selected from the group consisting of, 3,5-trimethylsiloxane, n-butyl-4,4-di-t-butylperoxyvalerate and combinations thereof can be used.

The vulcanizing agent is preferably included in an amount of 0.5 to 4.0 parts by weight based on 100 parts by weight of the raw material rubber, in that the raw material rubber is less sensitive to heat and chemically stable.

In addition, since the rubber composition for tire treads includes a coupling agent represented by Chemical Formula 1, it is necessary to adjust the weight ratio of the second coupling agent and the vulcanizing agent, and thus the second coupling agent and the vulcanizing agent. The weight ratio of may be 4: 1.25 to 8: 1.1.

When the weight ratio of the second coupling agent and the vulcanizing agent is within the above range, the low fuel consumption may be improved while maintaining various properties affecting the tire performance, and when the weight ratio of the second coupling agent and the vulcanizing agent is out of the above range, the general properties may be reduced. have.

The vulcanization accelerator refers to an accelerator that promotes the rate of vulcanization or promotes delay in the initial vulcanization stage.

Examples of the vulcanization accelerator include sulfenamide, thiazole, thiuram, thiourea, old anidine, dithiocarbamic acid, aldehyde-amine, aldehyde-ammonia, imidazoline, xanthate and these Any one selected from the group consisting of can be used.

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

Examples of the thiazole vulcanization accelerators 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 thiazole compound selected from the group consisting of ethyl 4-morpholinothio) benzothiazole and combinations thereof can be used.

Examples of the thiuram-based vulcanization accelerators include tetramethyl thiuram disulfide (TMTD), tetraethyl thiuram disulfide, tetramethyl thiuram monosulfide, dipentamethylene thiuram disulfide, dipentamethylene thiuram monosulfide and dipentamethylene. Any thiuram-based compound selected from the group consisting of thiuram tetrasulfide, dipentamethylene thiuram hexasulfide, tetrabutyl thiuram disulfide, pentamethylene thiuram tetrasulfide, and combinations thereof can be used.

As the thiourea vulcanization accelerator, for example, thiocarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea, and any combination thereof is selected from the group of thiourea Compounds can be used.

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

Examples of the dithiocarbamic acid-based vulcanization accelerators include ethylphenyldithiocarbamate zinc, butylphenyldithiocarbamate zinc, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, Zinc dibutyldithiocarbamate, zinc diamyldithiocarbamate, zinc dipropyldithiocarbamate, zinc salt of pentamethylenedithiocarbamate and piperidine, hexadecylisopropyldithiocarbamate zinc, octadecyl Isopropyldithiocarbamate zinc dibenzyldithiocarbamate zinc, sodium diethyldithiocarbamate, pentamethylenedithiocarbamate piperidine, dimethyldithiocarbamate selenium, diethyldithiocarbamate tellurium, dia One dithiocarbamic acid compound selected from the group consisting of cadmium didicarbamate and combinations thereof can be used.

The aldehyde-amine-based or aldehyde-ammonia based vulcanization accelerator, for example, acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde-ammonia reactant and combinations thereof -Amine based or aldehyde-ammonia based compounds can be used.

As said imidazoline type vulcanization accelerator, imidazoline type compounds, such as 2-mercaptoimidazoline, can be used, for example, As said xanthate type vulcanization accelerator, xanthate type, such as zinc dibutyl xanthogenate Compounds can be used.

The vulcanization accelerator may be included in an amount of 0.5 to 4.0 parts by weight based on 100 parts by weight of the raw material rubber in order to maximize productivity and rubber properties by promoting the vulcanization rate.

The vulcanization accelerator is a compounding agent used in combination with the vulcanization accelerator to complete its promoting effect. Any one selected from the group consisting of inorganic vulcanization accelerators, organic vulcanization accelerators and combinations thereof can be used. .

As the inorganic vulcanization accelerating aid, any one selected from the group consisting of zinc oxide (ZnO), zinc carbonate, magnesium oxide (MgO), lead oxide, potassium hydroxide and combinations thereof may 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. You can use either one.

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

When using the zinc oxide and the stearic acid together may be used in 1 to 5 parts by weight and 0.5 to 3 parts by weight with respect to 100 parts by weight of the raw material rubber, respectively, to serve as a suitable vulcanization accelerator.

The softener is added to the rubber composition to impart plasticity to the rubber to facilitate processing or to lower the hardness of the vulcanized rubber, and refers to oils and other materials used in rubber compounding or rubber production. The softener may be any one selected from the group consisting of petroleum oil, vegetable oil and combinations thereof, but the present invention is not limited thereto.

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

Representative examples of the paraffinic oil include P-1, P-2, P-3, P-4, P-5, and P-6 of Michang Oil, Inc. A representative example of the naphthenic oil is Michang oil. N-1, N-2, N-3, etc. of the corporation | Co., Ltd. are mentioned, As a representative example of the said aromatic oil, A-2, A-3, etc. of Michang Oil Corporation are mentioned.

However, it is known that cancer is more likely to occur when the content of polycyclic aromatic hydrocarbons (hereinafter referred to as "PAHs") included in the aromatic oils is 3% by weight or more with the recent increase of environmental awareness. , TDAE (treated distillate aromatic extract) oil, mild extraction solvate (MES) oil, residual aromatic extract (RAE) oil or heavy naphthenic oil can be preferably used.

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

The TDAE oil is advantageous in terms of environmental factors such as the low temperature characteristics of the tire tread including the TDAE oil, fuel efficiency, and the likelihood of causing cancer of PAHs.

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 It may be used any one selected from the group consisting of jojoba oil, macadamia nut oil, saflower flower oil, tung oil and combinations thereof.

The softening agent is preferably used in an amount of 0 to 150 parts by weight based on 100 parts by weight of the raw material rubber, in terms of improving the processability of the raw material rubber.

The anti-aging agent is an additive used to stop the chain reaction in which the 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.

Examples of the amine 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 can be used.

The phenolic anti-aging agent is 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 can be used.

As the quinoline anti-aging agent, 2,2,4-trimethyl-1,2-dihydroquinoline and derivatives thereof may be used, and specifically 6-ethoxy-2,2,4-trimethyl-1,2-di 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.

Wax hydrocarbon may be preferably used as the wax.

The anti-aging agent has a high solubility in rubber in addition to the anti-aging action, is low in volatility, inert to rubber, and does not inhibit vulcanization. It may be included in parts by weight.

The pressure-sensitive adhesive further improves the tack performance between the rubber and the rubber, and contributes to improving the physical properties of the rubber by improving the mixing, dispersibility and processability of other additives such as fillers.

As the pressure-sensitive adhesive, a natural resin pressure-sensitive adhesive such as rosin resin or terpene-based resin, and synthetic resin pressure-sensitive adhesive such as petroleum resin, coal tar or alkyl phenol resin may be used.

The rosin-based resin may be any one selected from the group consisting of rosin resin, rosin ester resin, hydrogenated rosin ester resin, derivatives thereof, and combinations thereof. The terpene-based resin may be any one selected from the group consisting of terpene resins, terpene phenol resins, and combinations thereof.

The petroleum resin is aliphatic resin, acid modified aliphatic resin, alicyclic resin, hydrogenated alicyclic resin, aromatic (C9) resin, hydrogenated aromatic resin, C5-C9 copolymer resin, styrene resin, styrene copolymer resin and It may be any one selected from the group consisting of a combination thereof.

The coal tar may be a coumarone-indene resin.

The alkyl phenol resin may be p-tert-alkyl phenol formaldehyde resin, the p-tert-alkyl phenol formaldehyde resin may be p-tert-butyl-phenol formaldehyde resin, p-tert-octyl-phenol formaldehyde and It may be any one selected from the group consisting of a combination thereof.

The pressure-sensitive adhesive may be included in 2 to 4 parts by weight based on 100 parts by weight of the raw material rubber. When the content of the pressure-sensitive adhesive is less than 2 parts by weight based on 100 parts by weight of the raw material rubber, the adhesive performance may be detrimental, and when the content of the pressure-sensitive adhesive exceeds 4 parts by weight, rubber properties may be reduced.

The rubber composition for a tire tread can be produced through a conventional two-step continuous manufacturing process. That is, during the finishing step in which the first step of thermomechanical treatment or kneading at a maximum temperature ranging from 110 to 190 ° C., preferably from 130 to 180 ° C. (called “non-production” step) and the crosslinking system are mixed, Typically can be prepared in a suitable mixer using a second step (called "production" step) of mechanical treatment at a low temperature of less than 110 ° C, for example 40 to 100 ° C, but the invention is not limited thereto. .

The rubber composition for the tire tread is not limited to the tread (tread cap and tread base), and may be included in various rubber components constituting the tire. Such rubber components include sidewalls, sidewall inserts, apex, chafers, wire coats or innerliners, and the like.

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

The tire may be a passenger car tire, a racing tire, an airplane tire, a farm 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, and is preferably a radial tire.

The rubber composition for tire tread of the present invention improves low fuel efficiency by using silica as a reinforcing filler and improves dispersibility of the silica, and uses a coupling agent that does not contain sulfur in the molecular structure, so Limitations can be overcome and emissions of hydrocarbons generated during or after tire manufacture can be reduced.

Hereinafter, an embodiment of the present invention will be described in detail so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

[Production Example: Production of Rubber Composition]

The ingredients and contents shown in Table 1 were mixed in a half-barrier mixer, and released at 150 ° C. to prepare rubber specimens, and then the unvulcanized physical properties were measured. . The physical property measurement results are shown in Table 2 below.

In Table 1 below, since TESPT contains sulfur in its molecular structure, some sulfur was corrected in Examples 1 to 4 for the application of 3-glycidoxyoxy dimethylethoxysilane containing no sulfur.

[Table 1] (Unit: parts by weight)

Comparative Example 1 Example 1 Example 2 Example 3 Example 4 S-SBR ¹⁾ 75 75 75 75 75 BR ²⁾ 25 25 25 25 25 Silica ³⁾ 80 80 80 80 80 TESPT ⁴⁾ 8 4 4 4 4 3-glycidoxypropyl dimethylethoxysilane - 3 6 10 10 Processing aid ⁵⁾ 4 4 4 - - Softener ⁶⁾ 30 30 30 30 25 Zinc oxide 3 3 3 3 3 Stearic acid One One One One One Antioxidant (6C) ⁷⁾ 2.5 2.5 2.5 2.5 2.5 DPG ⁸⁾ 1.5 1.5 1.5 1.5 1.5 brimstone 1.1 1.25 1.25 1.25 1.25 CBS ⁹⁾ 2 2 2 2 2 (week)
1) S-SBR: Styrene-butadiene rubber with Tg (glass transition temperature) of -25 to -20 ℃
2) BR: Butadiene rubber with Tg (glass transition temperature) of -106 ℃
3) Silica: Ultra 7000Gr (Degussa AG)
4) TESPT: Si69 (Degussa)
5) Processing aid: Struktol A60
6) Softener : TDAE Oil
7) Antioxidant (6C): N-1,3-dimethylbutyl-N-phenyl-p-phenylenediamine
8) DPG: Diphenylenguanidine
9) CBS: N-cyclohexyl-2-benzothiazyl sulfenamide

In Table 2 below, 300% modulus (Modulus) is the tensile strength at 300% elongation, measured according to the ISO 37 standard, the higher the value indicates excellent strength.

Abrasion index (Rambon) is a value of the wear ratio of the rubber worn by rotating at 25% of the sliding ratio at room temperature and a load of 1.5 kg at room temperature as a comparative example 1 as 100. The higher the value, the better the wear performance.

* Wear index = (wear amount of comparative example / wear amount of example) × 100

0 ° C tan δ is a measure of wet road braking performance, meaning that the higher the value, the better. 60 ° C tan δ is a measure of rotational resistance at 60 ° C.

Hydrocarbon emissions were stored in a certain amount of vulcanized compound rubber specimens at 160 ℃ for a certain period of time and collected and volatilized. The lower the value, the less hydrocarbon emissions.

* Hydrocarbon emission index = (volatile concentration of the example / volatile concentration of the comparative example) × 100

TABLE 2

Comparative Example 1 Example 1 Example 2 Example 3 Example 4 300% modulus (kgf / cm ² ) 95 92 90 93 98 Wear index 100 100 98 99 103 0 ℃ tan δ 0.311 0.307 0.309 0.310 0.315 60 ℃ tan δ 0.121 0.115 0.111 0.108 0.102 Hydrocarbon Emission Index
S 100 85 82 76 72

Referring to Table 2, it can be seen that in Examples 1 to 4, while maintaining the 300% modulus and 0 ℃ tan δ performance, hydrocarbon emissions, wear and 60 ℃ tan δ is superior 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 concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (6)

100 parts by weight of raw rubber, 20 to 90 parts by weight of silica, 4 to 8 parts by weight of the sulfide coupling agent, 3 to 10 parts by weight of coupling agent, and Vulcanizer Including; The coupling agent is 3-glycidoxy propyl dimethyl ethoxy silane represented by Formula 1 below, The weight ratio of the sulfide-based coupling agent and the vulcanizing agent is 4: 1.25 to 8: 1.1 rubber composition for the tire tread. [Formula 1]

(In the formula 1, R ₁ to R ₃ is an alkyl group having 1 to 4 carbon atoms, N is an integer of 3 to 7) delete delete The method of claim 1, The sulfide coupling agent is bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (4-triethoxysilylbutyl) tetrasulfide, bis (3-tri Methoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, bis (4-trimethoxysilylbutyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (2 -Triethoxysilylethyl) trisulfide, bis (4-triethoxysilylbutyl) trisulfide, bis (3-trimethoxysilylpropyl) trisulfide, bis (2-trimethoxysilylethyl) trisulfide, bis (4-trimethoxysilylbutyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide, bis (4-triethoxysilylbutyl) disulfide, bis ( 3-trimethoxysilylpropyl) disulfide, bis (2-trimethoxy Ylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthio Carbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropyl Benzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide and combinations thereof The rubber composition for tire treads, which is any one selected from the group. delete A tire manufactured using the rubber composition for tire tread according to claim 1.