KR102124196B1 - Rubber composition for tire belt and Tire comprising the same - Google Patents

Abstract

The present invention relates to a tire belt rubber composition comprising diatomaceous earth, to a tire belt comprising the rubber composition, and to a tire comprising the belt. The tire belt rubber composition has excellent heat-resistance and moist heat adhesion.

Description

Rubber composition for tire belt and tire comprising the same}

A tire belt rubber composition and a tire comprising the same.

In general, the belt of the tire functions to increase the rigidity of the tread portion by overlapping the steel cord layer. Therefore, the belt rubber should have good adhesion with the steel cord and should not be aged even after long-term driving. For this, belt rubber with high modulus and favorable fatigue performance is required.

The common cobalt salt of a steel cord coated rubber mixture promotes the crosslinking reaction of sulfur contained in this rubber mixture in large quantities. Due to this increase in crosslinking density, the pulling force between the rubber and the steel cord is increased.

More importantly, the cobalt salt forms cobalt (Co) ions from the brass surface during the crosslinking reaction, which helps to form copper sulfide (CuS).

The difference in efficiency between cobalt adhesion promoters is how quickly cobalt ions form. For example, zinc (Zn) or brass (Brass) works more easily with Cobalt Boron Decanoate Complexes than Cobalt Napthanate or Cobalt Stearate.

However, the adhesion between the cobalt compound and the steel cord weakens with increasing vehicle driving distance. This is an important issue as it is safety related.

The weakening of the adhesion may have several causes, but the penetration of water molecules [moisture] is one of the causes. Water molecules that have penetrated into the belt layer act as ligands to form bonds with steel cords or cobalt metals. As a result, -SH, -S- moieties of polymer chains that are coordinated with steel cords or cobalt metals B, the double-coupling parts come off, resulting in poor coupling force. In addition, corrosion of the steel cord by water molecules [moisture] is a natural result.

Therefore, it is important to prevent the penetration and progression of water molecules into the steel belt layer.

One aspect is to provide a tire belt rubber composition having excellent heat resistance and moist heat adhesion.

Another aspect is to provide a tire belt comprising the rubber composition.

Another aspect is to provide a tire with the tire belt.

According to one aspect,

A tire belt rubber composition comprising diatomaceous earth is provided.

According to the other aspect,

A tire belt comprising the tire belt rubber composition is provided.

According to another aspect,

A tire having the tire belt is provided.

According to one aspect, the tire belt rubber composition containing diatomaceous earth has excellent adsorption power to water molecules [moisture], thereby effectively inhibiting the progress of water molecules penetrating into the steel belt layer. Therefore, it is possible to prevent the weakening of the adhesive force between the rubber and the steel cord, which can greatly contribute to tire safety.

1 is a view schematically showing the structure of a tire according to an embodiment.

Hereinafter, a tire belt rubber composition and a tire will be described in more detail in an exemplary embodiment.

The creative idea disclosed in the present specification may apply various transformations and may have various implementations, so that specific implementations are described in detail in the detailed description, and specific implementations are illustrated in the drawings as necessary. Effects and features of the creative ideas of the present specification, and methods for achieving them will be clarified with reference to embodiments described below in detail along with the drawings. However, the creative spirit of the present specification is not limited to the embodiments disclosed below and may be implemented in various forms.

In the following embodiments, terms such as first and second are used for the purpose of distinguishing one component from other components, not limited meaning.

In the following embodiments, singular expressions include plural expressions, unless the context clearly indicates otherwise.

In the following embodiments, terms such as include or have mean that a feature or component described in the specification is present, and does not preclude the possibility of adding one or more other features or components.

When one embodiment can be implemented differently, a specific process order may be performed differently from the described order. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order opposite to that described.

Hereinafter, if necessary, embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be given the same reference numerals when described with reference to the drawings, and redundant description thereof will be omitted. Shall be

In the drawings, the size of components may be exaggerated or reduced for convenience of description. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of description, the creative ideas disclosed herein are not necessarily limited to those illustrated.

The tire belt rubber composition according to the embodiment includes diatomaceous earth.

Diatomaceous earth is a sedimentary rock deposited on the bottom after the diatoms that lived in lakes or marine sediments die. Diatomaceous earth is mainly composed of silicic acid (SiO ₂ ) and has a white or grayish white color. Diatomaceous earth is light and soft enough to get powder on your finger. On the other hand, diatomaceous earth is highly porous because it is a fine porous material. In modern times, it is used as a refractory material, and because of its strong absorption, it is mostly used as a filter material for purification of industrial water, water, pharmaceuticals, and food. In addition, it is also used as a filler for plastics and paper, an adsorbent for dynamite, a hemostatic agent, and a mixture of cement. The size ranges from 1 µm to 1 mm, but is usually in the range of 10 to 200 µm.

According to one embodiment of the present invention, the size of the diatomaceous earth contained in the tire belt rubber composition may be 1 to 110 μm. This size corresponds to a size that passes through 150 mesh. If it exceeds 110 µm, it may be a vulcanized rubber product, which may adversely affect the belt rubber as a physical foreign material, causing cracking.

According to one embodiment of the present invention, the belt rubber composition may include 0.5 to 7 parts by weight of diatomaceous earth with respect to 100 parts by weight of the raw rubber. If it is less than 0.5, the effect is insignificant, and if it exceeds 7, the heat-resistant adhesive strength and wet-heat adhesive strength are inferior.

According to an embodiment of the present invention, the rubber composition may include natural rubber as a raw rubber. The natural rubber may be a general natural rubber or a modified natural rubber.

The general natural rubber may be any of those known as natural rubber, and the origin and the like are not limited. The natural rubber includes cis-1,4-polyisoprene as a main body, but may also include trans-1,4-polyisoprene depending on the required characteristics. Therefore, in addition to natural rubber containing cis-1,4-polyisoprene as a main body, natural rubber containing trans-1,4-isoprene as a main body, such as Valata, which is a kind of rubber from Sapota family in South America, is mainly used as the main rubber. Rubber may also be included.

The modified natural rubber means that the general natural rubber is modified or purified. For example, the modified natural rubber includes epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber.

According to one embodiment of the present invention, the rubber composition may include a filler, and may include, for example, carbon black.

The carbon black may have a nitrogen adsorption specific surface area (nitrogen surface area per gram, N ₂ SA) of 30 to 300 m ² /g, and a DBP (n-dibutyl phthalate) oil absorption of 60 to 180 cc/100 g. It is not limited to this.

When the specific surface area of the nitrogen adsorption of the carbon black exceeds 300 m ² /g, the workability of the rubber composition for tires may be disadvantageous, and if it is less than 30m ² /g, the reinforcing performance by the carbon black as a filler may be adversely affected. In addition, if the DBP oil absorption amount of the carbon black exceeds 180 cc/100 g, the workability of the rubber composition may be deteriorated, and if it is less than 60 cc/100 g, the reinforcing performance by the carbon black as a filler may be disadvantageous.

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 30 to 80 parts by weight based on 100 parts by weight of the raw material rubber, preferably 45 to 75 parts by weight, and more preferably 53 to 67 parts by weight. If the content of the carbon black is less than 30 parts by weight, the reinforcing performance by the carbon black as a filler may be deteriorated, and if it exceeds 80 parts by weight, the processability of the rubber composition may be disadvantageous.

The tire belt rubber composition may further include various additives such as additional vulcanizing agents, vulcanization accelerators, vulcanization accelerators, anti-aging agents, antioxidants, or softeners. Any of the various additives may be used as long as they are commonly used in the field to which the present invention pertains, and their content is not particularly limited as it is in accordance with the compounding ratio used in the conventional tire belt rubber composition.

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

The vulcanizing agent is preferably contained in 0.5 to 10.0 parts by weight with respect to 100 parts by weight of the raw material rubber, as it is a suitable vulcanizing effect, making the raw material material less sensitive to heat and chemically stable.

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

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

Examples of the sulfenamide-based vulcanization accelerator include N-cyclohexyl-2-benzothiazylsulfenamide (CBS), N-tert-butyl-2-benzothiazylsulfenamide (TBBS), and 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 The sulfenamide-based compound 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 Ethyl 4-morpholinothio) benzothiazole and any thiazole-based compound selected from the group consisting of these can be used.

Examples of the thiuram-based vulcanization accelerator include tetramethyl thiuram disulfide (TMTD), tetraethyl thiuram disulfide, tetramethyl thiuram monosulfide, dipentamethylene thiuram disulfide, dipentamethylene thiuram monosulfide, and dipentamethylene. Thiuram tetrasulfide, dipentamethylene thiuram hexasulfide, tetrabutyl thiuram disulfide, pentamethylene thiuram tetrasulfide, and combinations thereof can be used.

The thiourea vulcanization accelerator may be any thiourea system selected from the group consisting of thiacarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea, and combinations thereof. Compounds can be used.

As the guanidine-based vulcanization accelerator, 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 accelerator include zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, Zinc dibutyldithiocarbamate, zinc diamyldithiocarbamate, zinc dipropyldithiocarbamate, zinc pentamethylenedithiocarbamate and piperidine, hexadecyl isopropyldithiocarbamate, zinc octadecyl Zinc isopropyldithiocarbamate dibenzyldithiocarbamate zinc, diethyldithiocarbamate sodium, pentamethylenedithiocarbamate piperidine, dimethyldithiocarbamate selenium, diethyldithiocarbamate tellurium, dia Any dithiocarbamate-based compound selected from the group consisting of cadmium mildiocarbamate and combinations thereof can be used.

The aldehyde-amine or aldehyde-ammonia-based vulcanization accelerator may be, for example, an aldehyde selected from the group consisting of acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde-ammonia reactant, and combinations thereof. -Amine-based or aldehyde-ammonia-based compounds can be used.

As the imidazoline-based vulcanization accelerator, for example, an imidazoline-based compound such as 2-mercaptoimidazoline can be used, and as the xanthate-based vulcanization accelerator, for example, xanthate-based zinc dibutylxanthogenate 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 to maximize productivity and rubber properties through acceleration of vulcanization.

The vulcanization accelerator is a blending agent used in combination with the vulcanization accelerator to complete its promoting 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 can be used.

In particular, the zinc oxide and the stearic acid may be used together as the vulcanization accelerator, and in this 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. By making it, the crosslinking reaction of the rubber is facilitated.

When the zinc oxide and the stearic acid are used together, they may be used in an amount of 1 to 10 parts by weight and 0.5 to 3 parts by weight with respect to 100 parts by weight of the raw material rubber, respectively, in order to serve as an appropriate vulcanization accelerator. When the content of the zinc oxide and the stearic acid is less than the above range, the vulcanization rate may be slow and productivity may be lowered.

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 refers to oils included in process oils or other rubber compositions. As the softener, any one selected from the group consisting of petroleum-based oil, vegetable oil, and combinations thereof may be used, but the present invention is not limited thereto.

As the petroleum oil, any one selected from the group consisting of paraffin oil, naphthenic oil, aromatic oil, and combinations thereof can be used.

Representative examples of the paraffinic oils include P-1, P-2, P-3, P-4, P-5, P-6, etc. of Michang Oil Co., Ltd., and typical examples of the naphthenic oils are Michang Oil N-1, N-2, N-3, etc. of Co., Ltd., and typical examples of the aromatic oils include A-2, A-3, etc. of Michang Oil Co., Ltd.

However, when the content of the polycyclic aromatic hydrocarbons (Polycyclic Aromatic Hydrocarbons, hereinafter referred to as PAHs) contained in the aromatic oil with a heightened environmental awareness is more than 3% by weight, it is known to have high cancer-causing potential, TDAE ( Treated distillate aromatic extract (OIL) oil, MES (mild extraction solvate) oil, RAE (residual aromatic extract) 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 with respect to the whole oil, 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 TDAE oil having 27 to 37% by weight and 38 to 58% by weight of paraffinic components can be preferably used.

The TDAE oil has excellent properties for environmental factors such as the possibility of causing cancer of PAHs while improving the low-temperature characteristics and fuel efficiency of the tire including the TDAE oil.

The vegetable 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, sage flower oil, copper oil, and any one selected from the group consisting of combinations thereof.

The softener is preferably used in an amount of 0 to 10 parts by weight based on 100 parts by weight of the raw material rubber, in order to improve 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 can be appropriately selected and used.

Examples of the amine-based anti-aging agent 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 phenol-based anti-aging agent is phenol-based 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-based 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 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.

The anti-aging agent is 1 to 10 based on 100 parts by weight of the raw material rubber in consideration of conditions such as high solubility in rubber in addition to the anti-aging action, small volatility, inertness to rubber, and not inhibiting vulcanization. It may be included in parts by weight.

The belt rubber composition according to an embodiment of the present invention may include, for example, 1.5 to 3.5 parts by weight of an amine-based anti-aging agent, for example, 2.3 to 2.7 parts by weight based on 100 parts by weight of the raw rubber.

The typical amount of the antioxidant may be included, for example, about 0.1 to about 5 parts by weight, for example, 0.1 to 1.0 parts by weight. Examples of antioxidants include, but are not limited to, diphenyl-p-phenylenediamine and others.

Belt rubber composition according to an embodiment of the present invention may include, for example, a quinoline-based antioxidant. The belt rubber composition according to an embodiment of the present invention may include, for example, 0.4 to 0.6 parts by weight of 2,2,4-TRIMETHYL-1,2-DIHYDROQUINOLINE as a quinoline-based antioxidant.

Referring to FIG. 1, the tire 10 includes a tread portion 100, a side wall portion 200, and a bead portion 300.

The tread portion 100 is a section in contact with the ground in cross-section, and serves to protect the tire from impact from the road surface, trauma, and the like. On the surface of the tread portion, a plurality of blocks partitioned by grooves may be formed for the drainage of the tire.

The sidewall 200 and the bead portion 300 are sequentially positioned on both sides along the width direction of the tire around the tread portion.

The sidewall 200 extends from both ends of the tread and forms a side surface of the tire. It withstands the repeated contraction and expansion during driving and protects the carcass layer 400 located on the inner surface. Do it.

The bead part 300 is provided at both ends of the sidewall 200 to surround the end of the cord paper, and the bead part 300 includes a bead core 500 including a steel wire in the form of a ring.

The carcass layer 400 is positioned between the left and right pair of bead parts 300 and is bonded to the tire rubber sheet inside the tire to form a skeleton of the tire, and the carcass layer 400 is a bead core 500 ) It is wound up from the inside of the tire to the outside.

The inner liner 700 is located on one side of the inner side of the carcass layer 400 and serves to prevent the air inside the tire from escaping out.

On the outer surface of the carcass layer 400 positioned on the tread portion 100, the belt layer 600 is positioned as a reinforcing layer that increases the elasticity of the tread and has controllability and stability.

A rubber composition according to an embodiment of the present invention is included in the belt layer. The internal pressure of the tire is significantly higher than atmospheric pressure, and as the driving time increases, the temperature becomes a high temperature exceeding 120°C. Therefore, it is important to ensure the safety of the vehicle under such high temperature and high pressure conditions. In particular, the steel belt plays a large role in physically supporting and protecting the tire against the load of the vehicle. Therefore, the adhesion between the steel cord and the rubber composition is important.

Water molecules that can remain in the rubber matrix even after vulcanization, or water molecules present in the inner space of the tire, diffuse and move through the inner liner to meet the steel cord and water molecules in the belt area. To form a bond with the steel cord or cobalt metal, and as a result, the -SH, -S- moieties, or double bond portions of the polymer chains that were coordinated with the steel cord or cobalt metal are separated, resulting in poor bonding force. Brings The corrosion of steel cords by the combination of water molecules and steel cords is a natural result.

According to an embodiment of the present invention, the diatomaceous earth contained in the tire belt rubber composition adsorbs water molecules in combination with water molecules, and thus can stop or slow the progression, movement of water molecules.

The content of the diatomaceous earth is as described above.

The tire belt rubber composition may include a cobalt compound.

The cobalt compound is a cobalt salt, a cobalt-boron ester, an organic acid cobalt salt, an inorganic acid cobalt salt, a non-cobalt salt, and the like, and as an adhesion system, a cobalt salt alone, a cobalt-RH, a cobalt-HRH resin (for example, Methylene receptor: phenolic, resorcinol, cresol, etc., or donor: hexamethylenetetraamine (HMT), hexamethoxymethylmelamine (HMMA), pentamethoxymethylmelamine (PMMA)] modified adhesive system, etc. have.

In general, to improve the adhesive strength, improve the adhesive system of the adhesive compound rubber (cobalt-RH, cobalt-HRH, their modification system), improve the performance and performance of the resin used as an adhesion aid, improve the cobalt salt used as an adhesion aid, improve adhesion Improvement of rubber vulcanization system, use of new formulations (reinforcing agents, carbon black, silica, polymers, chemicals) are used.

The content of the cobalt compound may include 0.2 to 5.0 parts by weight with respect to 100 parts by weight of the raw rubber, for example, 0.2 to 2.0 parts by weight, but is not limited thereto.

When the content of the cobalt compound is less than 0.2 parts by weight based on 100 parts by weight of the raw rubber, the effect of adding the silica is negligible, and when it exceeds 5.0 parts by weight, there may be a problem that adhesive strength decreases.

The tire belt rubber composition 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 from 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 a second step of mechanical treatment at a low temperature of 40 to 100 ℃, but is not limited thereto.

A tire belt according to another embodiment of the present invention includes the tire belt rubber composition.

A tire according to another embodiment of the present invention includes using the belt when forming a green tire. The method of manufacturing a tire belt using the tire belt rubber composition and a method of forming a green tire using a regular belt can be applied to any method that is conventionally used for the production of tires. Description is omitted.

A cap ply 800 including a hybrid cord may be disposed between the belt layer 600 and the tread portion 100. The cap ply 800 may maintain the tire performance by suppressing the flow of the belt layer 600 when driving.

1 illustrates the tire for a passenger car, but is not limited thereto, and may be a passenger car tire, a race tire, an airplane tire, an agricultural machinery tire, an off-the-road tire, a truck tire, or a bus tire. have. In addition, the tire may be a radial tire or a bias tire, and is preferably a radial tire.

The present invention is described in more detail through the following examples and comparative examples. However, the examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Diatomite preparation

Diatomaceous earth (trade name: EP Minerals® Celatom® DIATOMITE) was purchased and passed through 150 mesh to filter out parts with a particle size exceeding about 106 μm.

Example 1 to 4 and Comparative example 1 to 2

The composition shown in Table 1 was added to the Banbari mixer to mix the rubber compositions of Examples and Comparative Examples.

Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 Example 4 Natural rubber 100 100 100 100 100 100 Carbon black ^{1 )} 60 60 60 60 60 60 Stearic acid One One One One One One Active ZnO 10.0 10.0 10.0 10.0 10.0 10.0 Anti-aging ^{2 )} 2.5 2.5 2.5 2.5 2.5 2.5 Antioxidant ^{3 )} 0.5 0.5 0.5 0.5 0.5 0.5 Wax ^{4 )} 0.15 0.15 0.15 0.15 0.15 0.15 Cobalt ^{5 )} 1.0 1.0 1.0 1.0 1.0 1.0 sulfur 7.5 7.5 7.5 7.5 7.5 7.5 Accelerator ^{6 )} 0.5 0.5 0.5 0.5 0.5 0.5 Diatomaceous earth - 8 0.5 1.0 2.0 5

1) Carbon black: N326

2) Anti-aging agent: N-(1,3-DIMETHYLBUTYL)-N-PHENYL-P-PHENYLENDIAMINE

3) Antioxidants: 2,2,4-TRIMETHYL-1,2-DIHYDROQUINOLINE, POLYMERIZED

4) Wax: ISO-PARAFFINE + NORMAL PARAFFINE

5) Cobalt: COBALT BORO NEODECANOATE

6) Accelerator: N,N-Dicyclohexyl-2-benzothiazolesulfenamide

A steel cord (2+2x0.35 HT) was put in the rubber sheet prepared above, and a vulcanized specimen was prepared at 165°C for 16 minutes in a vulcanizer.

Evaluation example

The physical properties of the specimens prepared in Examples 1 to 4 and Comparative Examples 1 to 2 were evaluated as follows, and the results are shown in Table 2 below. The numerical values in Table 2 are shown by indexing Comparative Example 1 on the basis of 100, and the higher the heat resistance and wet heat adhesion values, the better.

Heat-resistance adhesiveness measurement

It was measured according to ASTM standard (D2229-04). The heat-resisting adhesive strength is a value representing the adhesive strength of steel cord and vulcanized rubber at high temperatures. The higher the value, the higher the safety of the tire.

Moist heat adhesion measurement

It was measured according to ASTM standard (D2229-04). Moist heat adhesion is a value that represents the adhesion between the steel cord and vulcanized rubber in a humid environment at high temperature. The higher the value, the higher the safety of the tire.

Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 Example 4 Heat-resistant adhesion 100 95 114 107 102 100 Moist heat adhesion 100 106 109 108 106 105

From the results of Table 2, it can be seen that the adhesion of the steel belts topping with the rubber compositions of Examples 1 to 4 containing diatomaceous earth is superior to that of Comparative Example 1 containing no diatomaceous earth.

It can be seen that Comparative Example 2, which contains 8 parts by weight of diatomaceous earth, shows lower adhesion than Examples 1 to 4. This indicates that the use of excessive diatomaceous earth results in a decrease in adhesion.

10: tire 100: tread
200: side wall part 300: bead part
400: carcass layer 500: bead core
600: belt layer 700: inner liner
800: cap fly

Claims (10)

Steel cord; And
Tire belt rubber composition comprising diatomaceous earth and cobalt compound;
Tire belt included. The tire belt according to claim 1, wherein the diatomaceous earth has a size of 1 to 110 μm. The tire belt according to claim 1, wherein the tire belt rubber composition contains 0.5 to 7 parts by weight of diatomaceous earth with respect to 100 parts by weight of the raw rubber. The tire belt according to claim 1, wherein the tire belt rubber composition contains 0.2 to 2.0 parts by weight of the cobalt compound relative to 100 parts by weight of the raw rubber. The tire belt according to claim 1, wherein the tire belt rubber composition contains 1.5 to 3.5 parts by weight of an amine-based anti-aging agent relative to 100 parts by weight of the raw rubber. The tire belt according to claim 1, wherein the tire belt rubber composition contains 0.1 to 1.0 parts by weight of a quinoline antioxidant relative to 100 parts by weight of the raw rubber. The tire according to claim 1, wherein the tire belt rubber composition comprises 2.3 to 2.7 parts by weight of N-(1,3-DIMETHYLBUTYL)-N-PHENYL-P-PHENYLENDIAMINE as an amine-based antioxidant for 100 parts by weight of the raw rubber. belt. The tire belt according to claim 1, wherein the tire belt rubber composition contains 0.4 to 0.6 parts by weight of 2,2,4-TRIMETHYL-1,2-DIHYDROQUINOLINE as a quinoline antioxidant relative to 100 parts by weight of the raw rubber. delete A tire having the tire belt of claim 1.

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