KR20120059117A - Rubber composition for tire lower beadfiller and tire manufactured by using the same - Google Patents

Abstract

PURPOSE: A rubber composition for tire lower beadfiller is provided to improve processability during tire production process, to improve modulus while maintaining tensile strength and elongation, and to improve durability of a tire. CONSTITUTION: A rubber composition for tire lower beadfiller comprises 100.0 parts by weight of crude rubber, 30-65 parts by weight of carbon black, 5-30 parts by weight of reinforcing resin, 1-10 parts by weight of methylene donor, and 1-10 parts by weight of process oil. The reinforcing resin has oil-absorption amount of 70-130 cc/100g, and nitrogen absorption surface area of 70-110 m^2/g. The reinforcing resin is selected from a group consisting of resorcinol formaldehyde resin, resol phenolic resin, a cashew-modified phenol resin in which m-cresol components a re removed, and combinations thereof.

Description

RUBBER COMPOSITION FOR TIRE LOWER BEADFILLER AND TIRE MANUFACTURED BY USING THE SAME

The present invention relates to a rubber composition for a bead filler of a tire and a tire manufactured using the same, wherein the tire can improve workability during a tire manufacturing process, maintain high tensile strength and maintain tensile strength and elongation, and improve durability. It relates to a rubber composition for the lower bead filler and a tire manufactured using the same.

In general, the bead filler of truck and bus tires has a low hardness bead filler rubber to prevent deformation of the bead portion due to high load, and low hardness and fatigue resistance to alleviate the impact of the load. It consists of this excellent upper bead filler rubber. Particularly, in the case of the bead filler, it is a very important factor for bead durability because it serves to suppress the occurrence of cracks by reducing the deformation of the carcass end, which accounts for most of the bead damage of the truck and bus tires. The carcass end of the tires for trucks and buses is the part with the most movement when the tire is running. In order to suppress the deformation of this tire, the carcass end has a very high hardness to firmly fix the bead and carcass to increase the rigidity of the entire bead part. Had bead filler rubber is required.

Accordingly, various techniques have been tried to produce tire bead filler rubber compositions for trucks and buses with high hardness. The most common technique is to use a large amount of carbon black or to increase the amount of vulcanizing agent. However, a rubber composition using a large amount of carbon black has an excessive load during the short-barrier mixing process and poor roll processability and extrudability, which inevitably prolongs the mixing times and times, resulting in low productivity and low energy efficiency. . In addition, rubber compositions which use sulfur and vulcanization accelerator excessively as vulcanizing agents are difficult to secure uniform properties due to insufficient dispersion of vulcanizing agents during field processing, poor field processability such as scorch, and high load pressure repeatedly transmitted. If the fatigue resistance and crack resistance is very disadvantageous, there is a problem that the bead portion rupture or crack occurs when used for a certain time.

In addition, the reinforcement resin and the methylene donor are used to improve the durability with high hardness and high modulus, but there is a problem that the tensile strength and elongation are lowered.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rubber composition for tire bead filler of a tire which can improve the workability during the tire manufacturing process and maintain durability and elongation rate while maintaining high modulus.

Another object of the present invention is to provide a tire having excellent durability, which is manufactured by using the rubber composition for the bead filler of the tire.

In order to achieve the above object, the rubber composition for the bead filler of a tire according to an embodiment of the present invention is 30 to 65 parts by weight of carbon black, 5 to 30 parts by weight of reinforcing resin, methylene based on 100 parts by weight of the raw material rubber 1 to 10 parts by weight of donor, and 1 to 10 parts by weight of process oil.

The carbon black may have a dibutyl phthalate oil absorption of 70 to 130 cc / 100 g and a nitrogen adsorption specific surface area (N ₂ SA) of 70 to 110 m ² / g.

The reinforcing resin is selected from the group consisting of resorcinol formaldehyde resin, resol phenolic resin, m-cresol-free cashew modified phenol resin, and combinations thereof. It may be.

The methylene donor may be selected from the group consisting of hexamethylenetetraamine (HMTA), hexamethoxymethylmelamine (HMMM), pentamethoxymethylmelamine (PMMM), and combinations thereof.

The process oil may be selected from the group consisting of aromatic base oils, lead-based base oils, distilled aromatic extract oils and combinations thereof.

The rubber composition for the lower bead filler of the tire is 30 to 65 parts by weight of carbon black having a dibutyl phthalate (DBP) oil absorption of 122 cc / 100 g and a nitrogen adsorption specific surface area of 92 m ² / g based on 100 parts by weight of raw rubber, and a reinforcing resin. 5 to 30 parts by weight of cashew-modified phenolic resin from which m-cresol has been removed, 1 to 10 parts by weight of hexamethylenetetraamine as methylene donor, and 1 to 10 parts by weight of lead-cenic base oil as process oil.

The rubber composition for the bead filler of the tire may further include 0.5 to 5 parts by weight of vulcanizing agent and 0.5 to 4 parts by weight of vulcanization accelerator with respect to 100 parts by weight of the raw material rubber.

Another object of the present invention is to provide a tire manufactured using the rubber composition for the bead filler of the tire.

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

The rubber composition for tire bead filler of the present invention is 30 to 65 parts by weight of carbon black, 5 to 30 parts by weight of reinforcing resin, 1 to 10 parts by weight of methylene donor, and 1 to about 5 parts by weight of raw material rubber. 10 parts by weight.

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

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

The general natural rubber may be used as long as it is known as natural rubber, and the 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, in addition to the natural rubber containing cis-1,4-polyisoprene as a main agent, for example, a natural containing trans-1,4-isoprene as a main agent such as a 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, examples of the modified natural rubber include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber.

Synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, chloro sulfonated 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, epoxy isoprene rubber, maleic acid ethylene propylene rubber, carboxylic acid Nitrile Butadiene High It may be a p-methyl styrene (brominated polyisobutyl isoprene-co-paramethyl styrene, BIMS), and one selected from the group consisting of -, bromo mineyi suited polyisobutyl isoprene-co.

The raw rubber may preferably include natural rubber and styrene butadiene rubber.

The styrene butadiene rubber may be emulsified polymerized styrene butadiene rubber (hereinafter referred to as E-SBR), solution-polymerized styrene butadiene rubber (hereinafter referred to as S-SBR), and a combination thereof. It may be any one selected from the group consisting of, preferably the styrene butadiene rubber may be an emulsion polymerization styrene butadiene rubber. When the emulsion-polymerized styrene butadiene rubber is used as the styrene butadiene rubber, scorch stability and easy processability can be secured.

The emulsion-polymerized styrene butadiene rubber may have a styrene content of 20 to 28% by weight, and a vinyl content in butadiene of 18% by weight or more. When using the emulsion-polymerized styrene butadiene rubber having a vinyl content in the styrene and butadiene in the above range it can be excellent in fuel efficiency performance and processability.

The emulsion polymerization styrene butadiene rubber may have a glass transition temperature of -55 to -45 ℃. In the case of using the emulsion-polymerized styrene butadiene rubber having a glass transition temperature in the above range it can ensure the rotational resistance performance.

In addition, when using a mixture of natural rubber and styrene butadiene rubber as the raw material rubber, it may include 50 to 90 parts by weight of natural rubber and 10 to 50 parts by weight of styrene butadiene rubber, more preferably 65 to 85 parts by weight of natural rubber And 15 to 35 parts by weight of styrene butadiene rubber.

When the raw rubber includes more than 90 parts by weight of the natural rubber may be disadvantageous in terms of processability, when less than 50 parts by weight may have a slight effect of improving the specific tensile strength through the natural rubber. .

When the styrene butadiene rubber is included in an amount of more than 50 parts by weight of the raw material rubber, physical properties such as tensile strength may be lowered, and when the styrene butadiene rubber is used in an amount of less than 10 parts by weight, workability may be disadvantageous.

The carbon black may have a dibutyl phthalate (DBP) oil absorption of 70 to 130 cc / 100 g, a nitrogen adsorption specific surface area (N ₂ SA) of 70 to 110 m ² / g, Preferably, the DBP oil absorption is 122 cc / 100 g and the nitrogen adsorption specific surface area is 92 m ² / g.

When the DBP oil absorption of the carbon black exceeds 130cc / 100g, the workability of the rubber composition may be lowered. If the DBP oil absorption is less than 70cc / 100g, the reinforcing performance of the carbon black as a filler may be disadvantageous. In addition, when the nitrogen adsorption specific surface area of the carbon black exceeds 110m ² / g may be detrimental processability of the rubber composition for the tire, less than 70m ² / g may be disadvantageous reinforcement performance by the carbon black filler.

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.

The carbon black may be included in an amount of 30 to 65 parts by weight based on 100 parts by weight of the raw material rubber. When the content of the carbon black is less than 30 parts by weight, the reinforcing performance by the carbon black as a filler may decrease, and when the content of the carbon black exceeds 65 parts by weight, the processability of the rubber composition may be reduced.

The reinforcing resin may be selected from the group consisting of resorcinol formaldehyde resin, resol phenolic resin, cashew modified phenol resin from which m-cresol is removed, and combinations thereof, preferably m-cresol This removed cashew modified phenolic resin can be used.

The cashew-modified phenolic resin from which the m-cresol was removed may include m-cresol in an amount of 1 wt% or less.

In addition, the cashew-modified phenolic resin may be a modification ratio of the cashew oil is 30 to 50% by weight.

The cashew modified phenol resin may be prepared by various methods, for example, using an acid catalyst and reacting phenol, cresol, resorcinol and the like with aldehydes such as formaldehyde, paraformaldehyde or benzaldehyde, and then cashew oil. It can also be prepared by reforming. In this case, as the acid catalyst, oxalic acid, hydrochloric acid, sulfuric acid, and p-toluene sulfonic acid may be used.

The reinforcing resin may include 5 to 30 parts by weight based on 100 parts by weight of the raw material rubber. When the reinforcing resin is included in an amount of less than 5 parts by weight based on 100 parts by weight of the raw material rubber, the reinforcing effect by the cashew-modified phenolic resin may be insignificant, and when it contains more than 30 parts by weight, workability may be disadvantageous.

The methylene donor allows the reinforcing resin to have a thermoplastic. In addition, when the methylene donor is included in the rubber composition together with the reinforcing resin, physical properties such as hardness, toughness, stiffness, tear resistance, and the like may be improved.

The methylene donor may be selected from the group consisting of hexamethylenetetraamine (HMTA), hexamethoxymethylmelamine (HMMM), pentamethoxymethylmelamine (PMMM), and combinations thereof, preferably hexamethylene Tetraamines can be used.

The methylene donor may be included in an amount of 1 to 10 parts by weight based on 100 parts by weight of the raw material rubber. When the methylene donor is included in an amount of less than 1 part by weight based on 100 parts by weight of the raw material rubber, the effect of including the methylene donor may be insignificant, and when used in excess of 10 parts by weight, workability may be reduced.

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

Representative examples of the naphthenic process oil include N-1, N-2, N-3, etc. of Michang Oil Co., Ltd. Examples of the aromatic process oil include A-2, A-3, etc. of Michang Oil Co., Ltd. Can be mentioned.

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

The process oil has a total content of PAHs component of 3% by weight or less, a kinematic viscosity of 95 or more (210 ° F. SUS), 15-25% by weight of an aromatic component in the process oil, and 27-27 parts of a naphthenic component. 37% by weight and paraffinic component may be 38 to 58% by weight of TDAE oil.

The process oil is advantageous in terms of environmental factors such as the low-temperature properties and fuel economy performance of the rubber composition including the process oil, while also causing cancer of PAHs.

The process oil may preferably be selected from the group consisting of A # 2 oil as aromatic process oil, N # 2 oil (naphthanic base oil), TDAE oil and combinations thereof as naphthenic process oil.

The process oil is preferably included in 1 to 10 parts by weight based on 100 parts by weight of the raw material rubber.

The tire bead filler rubber composition may further include a vulcanizing agent.

As said vulcanizing agent, a sulfur type vulcanizing agent can be used preferably. 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 vulcanizing agent is preferably included in an amount of 0.5 to 5 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.

The tire bead filler rubber composition may further include a vulcanization accelerator.

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

The vulcanization accelerators include sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamic acid, aldehyde-amine, aldehyde-ammonia, imidazoline, xanthate and their Any one selected from the group consisting of a combination 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 rubber composition for the tire bead filler may optionally further include various additives such as additional vulcanization accelerators, fillers, coupling agents, 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 rubber composition for the bead filler tire.

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.

The vulcanization accelerator may be included in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the raw rubber to serve as a suitable vulcanization accelerator.

The filler may be any one selected from the group consisting of silica, calcium carbonate, clay (aluminum hydride silicate), aluminum hydroxide, lignin, silicate, talc and combinations thereof. The filler may be included in 0.5 to 10 parts by weight based on 100 parts by weight of the raw rubber.

Examples of the coupling agent include a sulfide silane compound, a mercapto silane compound, a vinyl silane compound, an amino silane compound, a glycidoxy silane compound, a nitro silane compound, a chloro silane compound, a methacryl silane compound, and a combination thereof. Any one selected from the group consisting of can be used, and sulfide-based silane compounds can be preferably used.

The sulfide-based silane compound may be 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 Sisylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethyl Thiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide and combinations thereof It may be any one selected from the group consisting of.

The mercapto silane compound is 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane and combinations thereof It may be any one selected from the group consisting of. The vinyl silane compound may be any one selected from the group consisting of ethoxysilane, vinyltrimethoxysilane, and combinations thereof. The amino silane compound 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 silane compounds include γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropylmethyldimethoxysilane And combinations thereof may be any one selected from the group consisting of. The nitro silane compound may be any one selected from the group consisting of 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and combinations thereof. The chloro-based silane compound is selected from the group consisting of 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, and combinations thereof. It can be any one.

The methacrylic silane compound is any one selected from the group consisting of γ-methacryloxypropyl trimethoxysilane, γ-methacryloxypropyl methyldimethoxysilane, γ-methacryloxypropyl dimethyl methoxysilane, and combinations thereof Can be.

The coupling agent may be included in an amount of 1 to 20 parts by weight based on 100 parts by weight of the raw material rubber to improve dispersibility of the silica. When the content of the coupling agent is less than 1 part by weight, the improvement of dispersibility of silica may be insufficient, resulting in deterioration of the processability of the rubber or low fuel consumption performance. When the content of the coupling agent is more than 20 parts by weight, the interaction between silica and rubber is so strong that the fuel efficiency is low. May be good but the braking performance may be very poor.

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. As the wax, paraffin wax, waxy hydrocarbon, microcrystalline wax may be used, and preferably waxy hydrocarbon may be used.

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.

In general, when the content of the carbon black in the rubber composition for the bead filler of the tire is increased, the shear rubber is formed by forming the bound rubber and thereby the reinforcing effect. In addition, the pattern viscosity increases and the scorch time decreases, resulting in poor workability. In addition, the elongation rate decreases instead of the modulus rising.

On the other hand, in the present invention, by adding a large amount of a reinforcing resin that can significantly increase the modulus but maintain the elongation rate to the rubber composition, the content of carbon black can be reduced to improve processability, and the elongation rate can be maintained.

In addition, by using the reinforcing resin together with the methylene donor, it is possible to significantly increase the hardness and strength compared to the case of using only the reinforcing resin and methylene donor alone. The reinforcing resin hardly affects the mixing or processing during processing of the rubber composition, but when the reinforcing resin is used together with the methylene donor, the methoxy group of the methylene donor during vulcanization is reinforced with the reinforcing resin, such as the m-cresol component. Reaction with the hydroxy group (-OH) of the removed cashew modified phenol resin generates a methylene bridge between the melamine structure and the reinforcing resin to generate a thermosetting resin network.

Thus, in the present invention, by including a large amount of reinforcing resin with a methylene donor compared to the conventional rubber composition to increase the hardness and modulus while reducing the amount of carbon black and vulcanizing agent to maintain tensile strength and elongation improved durability Can be represented. In addition, since the pattern viscosity may increase with increasing usage of the reinforcing resin, processing may be difficult, and thus, processability may be improved by adding process oil.

Accordingly, the rubber composition for a tire according to the present invention may be included in various rubber components constituting the tire in addition to the tire bead filler. Such rubber components include treads (tread caps and tread bases), 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 composition for the tire lower bead filler. The method for manufacturing a tire using the tire bead filler rubber composition may be applied to any method used in the manufacture of tires in the related art, and thus, detailed description thereof will be omitted.

The tire may preferably be a truck tire or a bus tire, but is not limited thereto, and may be a tire for a car, a racing tire, an airplane tire, an agricultural tire, an off-the-road tire, or the like. In addition, the tire may be a radial tire or a bias tire, and is preferably a radial tire.

Since the rubber composition for tire lower bead filler of the present invention has improved workability and high modulus and at the same time maintains tensile strength and elongation, it is possible to manufacture a tire having excellent durability.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice 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]

Next, the components as shown in Table 1 were added to the half-barrier mixer to prepare a rubber composition according to the following Examples and Comparative Examples, followed by vulcanization at 150 ° C. for 30 minutes to prepare a specimen.

Item Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Raw material rubber ^① 100 100 100 100 Carbon Black ^② 75 75 55 55 Reinforcement resin ^③ 0 10 20 20 Methylene donor ^④ 0 5 5 5 Process oil ^⑤ 0 0 0 10 brimstone 4.5 4.5 4.5 4.5 Vulcanization accelerator 1.5 1.5 1.5 1.5

(Unit: parts by weight)

① Raw material rubber: SIR-20 (polyisoprene block rubber): SBR1502 (styrene butadiene rubber 1502) = 60:40 (weight ratio)

② Carbon black: Carbon black with dibutyl phthalate (DBP) oil absorption 122cc / 100g, nitrogen adsorption specific surface area 92m ² / g

③ Reinforcement resin: Cashew modified phenolic resin with m-cresol component removed

④ methylene donor: Hexamethylenetetramine (HMTA)

⑤ Process Oil: Lead Scenic Base Oil (N # 2, Michang Petroleum Industries)

The physical properties of the bead portion rubber specimens of the tires prepared from the rubber compositions of Examples and Comparative Examples were measured in the following manner, and the results are shown in Table 2. However, the value shown in Table 2 below shows a relative value based on the measured value of the comparative example, the larger the value, the better.

Hardness was measured according to DIN 53505. Hardness indicates steering stability. The higher the value, the better the steering stability.

100% modulus (Modulus, unit kgf / cm 2) is the tensile strength at 100% elongation, measured according to the ISO 37 standard, and the higher the value, the better the strength.

Tensile strength (Kgf / cm ² ) was measured by the method of ASTM D 790, the higher the value indicates the stronger the elongation.

Elongation (%) means the elongation at break, which was measured by the method of expressing the strain value in percent until the test piece is broken in the tensile tester. The higher the value, the more flexible the rubber, the more elongated.

Mooney viscosity (ML1 + 4, 125 ° C) was measured using a Mooney MV2000 (Alpha Technology) instrument at Large Rotor, preheat 1 minute, rotor run time 4 minutes, temperature 125 ° C.

Item Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Tensile Properties Hardness 100 106 108 109 100% modulus 100 197 210 207 The tensile strength 100 54 95 100 Elongation rate 100 46 106 101 Processability Mooney viscosity 100 99 96 107

Referring to Table 2, the rubber composition of Example 1, which reduces the content of carbon black according to the present invention and includes a large amount of reinforcing resin and a methylene donor, has a higher hardness and modulus than the rubber compositions of Comparative Examples 1 to 3. At the same time, it can be seen that tensile strength and elongation are also maintained. In addition, the process oil was also improved by including the process oil, it was confirmed that it is suitable for the physical properties of the bead filler for trucks and buses.

Since the rubber composition for tire lower bead filler of the present invention can have improved workability and high modulus and at the same time maintain tensile strength and elongation, tires having excellent durability can be manufactured using the rubber composition.

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 (8)

Per 100 parts by weight of the raw material rubber,
30 to 65 parts by weight of carbon black,
5 to 30 parts by weight of the reinforcing resin,
1 to 10 parts by weight of methylene donor, and
1 to 10 parts by weight of process oil
Rubber composition for the bead filler of the tire comprising a. The method of claim 1,
The carbon black has a dibutyl phthalate oil absorption of 70 to 130cc / 100g, the nitrogen adsorption specific surface area of 70 to 110m ² / g rubber composition for the lower bead filler of the tire. The method of claim 1,
The reinforcing resin is selected from the group consisting of resorcinol formaldehyde resin, resol phenolic resin, cashew modified phenol resin from which m-cresol component is removed, and a combination of rubber filler for tire bead fillers. . The method of claim 1,
The methylene donor is hexamethylenetetraamine, hexamethoxymethylmelamine, pentamethoxymethylmelamine, rubber composition for the bead filler of the tire, characterized in that selected from the group consisting of. The method of claim 1,
The process oil is a rubber composition for the bead filler of the tire, characterized in that selected from the group consisting of aromatic process oil, lead sennic base oil, distilled aromatic extract oil and combinations thereof. The method of claim 1,
Per 100 parts by weight of the raw material rubber,
30 to 65 parts by weight of carbon black having a dibutyl phthalate oil absorption of 122 cc / 100 g and a nitrogen adsorption specific surface area of 92 m ² / g,
5 to 30 parts by weight of cashew modified phenolic resin, from which m-cresol was removed as a reinforcing resin,
1 to 10 parts by weight of hexamethylenetetraamine as methylene donor, and
1 to 10 parts by weight of lead sensic base oil,
Rubber composition for the bead filler of the tire comprising a. The method of claim 6,
The rubber composition for tire bead filler of the tire further comprises 0.5 to 5 parts by weight of vulcanizing agent and 0.5 to 4 parts by weight of vulcanization accelerator based on 100 parts by weight of the raw material rubber. A tire manufactured using the rubber composition for the bead filler of a tire according to any one of claims 1 to 7.