JP6362546B2 - Manufacturing method of tire rubber composition and tire - Google Patents

Description

  The present invention relates to a method for producing a tire rubber composition and a tire having a tire member made of the tire rubber composition produced by the production method.

  Currently, silica-containing rubber compositions are used not only for treads but also for various tire members because of demands for reducing fuel consumption of tires. However, since silica has a hydrophilic silanol group on its surface, it has lower affinity with rubber components (especially natural rubber, butadiene rubber, styrene butadiene rubber, etc., which are often used for tire members) and wear resistance compared to carbon black. There exists a problem that property and mechanical strength (tensile strength and elongation at break) are inferior.

  As a method of improving such a problem, a method of enhancing the reaction between a rubber component and silica using a coupling agent is known. However, ordinary coupling agents have a problem that their own functional groups react and aggregate before reacting with silica, and there is a limit to the dispersion effect of silica. Further, a method is known in which a modifying group that reacts with silica is introduced into a rubber component to increase the reactivity between the rubber component and silica. However, these methods still have room for improvement in both workability and fuel efficiency.

  Furthermore, in recent years, not only low fuel consumption but also wear resistance has been demanded from the viewpoint of resource protection. As a method for improving the wear resistance, a method using fine silica with high reinforcing properties is known. However, fine-particle silica is generally very difficult to disperse in a rubber composition, and it cannot sufficiently disperse, leaving an agglomerate, which cannot sufficiently improve wear resistance and mechanical strength. There is a problem of making it worse.

  Patent Document 1 discloses a technique for improving the fuel economy, wet grip performance, and processability of a rubber composition in a well-balanced manner by using a predetermined silane coupling agent 1 and silane coupling agent 2 together. Yes. However, there is still room for improvement in achieving both wet grip performance and low fuel consumption. In addition, improvement of wear resistance is not considered.

  Furthermore, when silica is blended in a large amount to improve fuel efficiency, the electrical resistance of the tire increases, so there is a risk of sparking due to static electricity when fueling the vehicle, for example, which may ignite the fuel. There is a problem with safety.

  Patent Document 2 describes a tire in which rolling resistance is reduced without lowering the conductivity of the tire by laying a conductive thin film on a tread portion and a sidewall portion. However, this technique complicates the tire manufacturing process and has a problem in cost, and therefore, a rubber composition that can easily improve fuel economy and conductivity in a well-balanced manner is required.

JP2012-82325A JP-A-8-230407

  The present invention comprises a method for producing a tire rubber composition having improved fuel economy, wear resistance, wet grip performance and conductivity in a well-balanced manner, and a tire rubber composition produced by the production method. It aims at providing the tire which has a tire member.

  As a result of intensive studies, the inventors of the present invention kneaded the components other than the vulcanizing agent at the same time, the base kneading step X, and the kneaded product obtained in step X by adding the vulcanizing agent and kneading. Rather than the conventional kneading method for performing the final kneading step F, the cups are made by adding the predetermined filler and the coupling agent in portions and kneading the step X1 and the step X2 and the kneading method for performing the step F. It was found that the above problems can be solved by preventing the aggregation of the ring agent and promoting the reaction with silica and improving the conductivity, and succeeded in completing the present invention through further studies. did.

That is, the present invention relates to a rubber component (A) containing at least one selected from the group consisting of natural rubber and diene-based synthetic rubber, silica (B), carbon black 1 having a nitrogen adsorption specific surface area of 200 m ² / g or less ( C1), a carbon black 2 (C2) having a nitrogen adsorption specific surface area of 900 m ² / g or more, a coupling agent (D) represented by the following chemical formula (1), and a vulcanizing system containing a vulcanizing agent and a vulcanization accelerator A method for producing a tire rubber composition containing a drug (E), comprising:
(Step X1) Step X1 of kneading part or all of A, B, part of C1, D, and optionally part of E,
(Step X2) The kneaded product of Step X1, the remaining amount of B, the remaining amount of C2, D, and optionally Step X2 of kneading a part of E, and (Step F) the kneaded material of Step X2, and E Process F for kneading the remaining amount
The manufacturing method of the rubber composition for tires containing this.
Formula _{(1) (C p H 2p} + 1 O) 3 -Si- (CH 2) q -S-CO-C k H 2k + 1
(In chemical formula (1), p represents an integer of 1 to 3, q represents an integer of 1 to 5, and k represents an integer of 5 to 12.)

  The rubber component preferably contains styrene butadiene rubber and / or butadiene rubber having a functional group that reacts with silica.

  The DBP oil absorption of carbon black 2 (C2) is preferably 300 ml / 100 g or more.

The rubber composition preferably has a volume resistivity of less than 1.0 × 10 ⁷ Ω · cm.

  It is preferable that the addition amount of silica in the step X1 is 50 to 95% by mass of the total addition amount of silica.

  Furthermore, it is a manufacturing method of the rubber composition containing a plasticizer, It is preferable to knead | mix 50 mass% or more of the total addition amount of a plasticizer in process X1.

  It is preferable that the maximum temperature in process X1 and / or process X2 is 140 to 200 degreeC.

  After the kneading in the step X1 and / or the step X2, it is preferable to include a step of holding the kneaded material at 150 to 190 ° C. for 10 to 120 seconds.

  In step X1 and / or step X2, it is preferable to knead part or all of the vulcanization accelerator.

  Furthermore, it is a manufacturing method of the rubber composition containing an anti-aging agent, and it is preferable to knead the anti-aging agent in the step X2.

  Furthermore, it is a manufacturing method of the rubber composition containing a surfactant, and it is preferable to knead the surfactant in the step X1 and / or the step X2.

  Moreover, this invention relates to the tire which has a tire member comprised with the rubber composition for tires manufactured with said manufacturing method.

  According to the present invention, a predetermined rubber component (A), silica (B), carbon black 1 (C1) and carbon black 2 (C2) having a predetermined nitrogen adsorption specific surface area, a predetermined coupling agent (D), and an additive A method for producing a rubber composition for a tire containing a vulcanizing agent (E) containing a vulcanization agent and a vulcanization accelerator, and according to the production method including the predetermined step X1, step X2 and step F, is low fuel consumption A method for producing a tire rubber composition with improved balance, wear resistance, wet grip performance and electrical conductivity, and a tire having a tire member composed of the tire rubber composition produced by the production method Can be provided.

  The tire rubber composition according to the present invention includes a predetermined rubber component (A), silica (B), carbon black 1 (C1) and carbon black 2 (C2) having a predetermined nitrogen adsorption specific surface area, and a predetermined coupling. And a vulcanizing agent (E) containing a vulcanizing agent and a vulcanization accelerator.

Rubber component (A)
The rubber component (A) includes at least one selected from the group consisting of natural rubber and diene synthetic rubber, and preferably includes at least two. By blending a plurality of diene rubbers, defects of a specific rubber can be compensated and physical properties can be improved in a balanced manner. These rubber components are preferably those in which the main chain and terminals of the rubber are modified with a modifying agent. Further, some of them may have a branched structure by using a polyfunctional type, for example, a modifier such as tin tetrachloride or silicon tetrachloride. In addition, what is necessary is just to select suitably according to an application member etc. about a rubber component kind and compounding quantity.

  Examples of the natural rubber include natural rubber (NR), modified natural rubber such as epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), and high-purity natural rubber (HPNR). Etc. are also included.

  The NR is not particularly limited, and those generally used in the tire industry such as SIR20, RSS # 3, TSR20, and the like can be used.

  The content in the rubber component (A) in the case of containing NR is preferably 5% by mass or more, and more preferably 10% by mass or more, because the fracture resistance of the rubber composition is improved. Further, the content of NR is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 50% by mass or less, because it is excellent in fuel efficiency and wear resistance.

  Examples of the diene-based synthetic rubber include isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), and styrene isoprene butadiene rubber (SIBR).

  Among diene-based synthetic rubbers, it is preferable to include SBR because it is excellent in processability and grip properties. Although it does not specifically limit as said SBR, Undenatured solution polymerization SBR (S-SBR), Undenatured emulsion polymerization SBR (E-SBR), These modified SBR (Modified S-SBR, Modified E-SBR), etc. Is mentioned. Examples of the modified SBR include modified SBR having a terminal and / or main chain modified, modified SBR coupled with tin, a silicon compound, or the like (condensate, one having a branched structure, or the like). Among these SBRs, S-SBR and modified S-SBR are preferable because the grip performance and wear resistance can be improved in a well-balanced manner. From the viewpoint of reaction with silica, a silyl group, amino group, amide group, Particularly preferred is a modified S-SBR having at least one selected from the group consisting of a hydroxyl group and an epoxy group. These SBRs may be used singly, but SBRs having different physical properties such as styrene content may be used in combination depending on applications. In addition, what is necessary is just to select suitably according to an application member.

The styrene content of SBR is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 20% by mass or more from the viewpoints of dry grip performance, wet grip performance and rubber strength. Further, the styrene content of SBR is preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less from the viewpoint of low fuel consumption. In addition, the styrene content of SBR in the present specification is a value calculated by ¹ H-NMR measurement.

The vinyl bond amount of SBR is preferably 10 mol% or more, more preferably 15 mol% or more, and even more preferably 20 mol% or more from the viewpoints of dry grip performance, wet grip performance and rubber strength. The vinyl bond amount of SBR is preferably 65 mol% or less, more preferably 60 mol% or less, and further preferably 30 mol% or less from the viewpoint of low fuel consumption. In addition, the vinyl bond amount of SBR in this specification shows the vinyl bond amount of a butadiene part, and is a value computed by < ¹ > H-NMR measurement.

  In the case of containing SBR, the content in the rubber component (A) is preferably 10% by mass or more, more preferably 20% by mass or more, and further preferably 30% by mass or more from the viewpoints of dry grip properties and wet grip properties. Moreover, 90 mass% or less is preferable from a wear-resistant viewpoint, and, as for content of SBR, 80 mass% or less is more preferable.

  Moreover, it is preferable that BR is included from the reason of being excellent in abrasion resistance. A rubber composition in which a white filler such as silica (B) is blended with BR generally has a problem that it is difficult to obtain desired performance because the dispersibility of the filler is low. However, in the present invention, the reaction between the filler and the rubber component is enhanced by dividing and kneading the predetermined coupling agent (D). Therefore, the dispersibility of the filler can be improved, fuel efficiency and wear resistance can be improved, and good processability can be obtained, and the balance of these performances can be improved synergistically.

  Examples of the BR include a high cis BR having a cis content of 90% or more, a modified BR having a terminal and / or main chain modified, a modified BR coupled with tin, a silicon compound, or the like (condensate having a branched structure) Etc.). Among these BRs, high-cis BR is preferable from the viewpoint that excellent wear resistance can be obtained, and in terms of reaction with silica, modified BR having a modified terminal and / or main chain, particularly a silyl group, A modified BR having at least one selected from the group consisting of an amino group, an amide group, a hydroxyl group, and an epoxy group is preferable. In addition, what is necessary is just to select suitably according to an application member.

  In the case of containing BR, the content in the rubber component (A) is preferably 5% by mass or more, more preferably 8% by mass or more, and further preferably 10% by mass or more from the viewpoint of wear resistance. Further, the BR content is preferably 80% by mass or less, more preferably 75% by mass or less, and further preferably 70% by mass or less from the viewpoint of workability.

  In particular, the modified SBR and the modified BR usually have a strong functional group reaction, so that the rubber component itself aggregates and dispersion of the filler is often difficult. However, in the present invention, a predetermined coupling agent (D ) Is kneaded and kneaded to prevent aggregation of the rubber component and promote reaction with silica.

Silica (B)
The silica (B) is not particularly limited, and those commonly used in the tire industry can be used. For example, dry process silica (anhydrous silicic acid), wet process silica (hydrous silicic acid) and the like can be mentioned, but wet process silica is preferred because of the large number of silanol groups.

Silica nitrogen adsorption specific surface area (N ₂ SA) of (B) is in view 40 m ² / g or more is preferred from the breaking strength, more preferably at least 50 m ² / g, more preferably at least 100m ² / g, 130m ² / g or more is particularly preferable, and 160 m ² / g or more is most preferable. Also, N ₂ SA of the silica (B), from the viewpoint of fuel economy and workability 500 meters ² / g or less, more preferably not more than 300 meters ² / g, more preferably from 250 meters ² / g or less, 200 meters ² / Particularly preferred is g or less. Incidentally, N ₂ SA of the silica (B) in the present specification is a value measured by the BET method in accordance with ATSM D3037-81.

  The content (total addition amount) of silica (B) is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, from the viewpoint of fuel efficiency and wet grip performance with respect to 100 parts by mass of the rubber component (A). 30 parts by mass or more is more preferable, and 40 parts by mass or more is particularly preferable. The total content of silica (B) is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and still more preferably 120 parts by mass or less from the viewpoints of dispersibility of the filler in the rubber component and processability.

Carbon Black The tire rubber composition according to the present invention is a carbon black having a nitrogen adsorption specific surface area (N ₂ SA) of 200 m ² / g or less and a carbon black of N ₂ SA of 900 m ² / g or more. 2 (C2) is contained. By using carbon black 1 and carbon black 2 in combination, fuel economy, wear resistance, wet grip performance and conductivity can be improved in a well-balanced manner. In addition, you may use together with carbon black other than carbon black 1 (C1) and carbon black 2 (C2).

Carbon black 1 (C1) is not particularly limited as long as the nitrogen adsorption specific surface area is 200 m ² / g or less, and GPF, FEF, HAF, ISAF, SAF, etc., which are common in the tire industry can be used alone. Even if it uses, 2 or more types may be used together.

The nitrogen adsorption specific surface area (N ₂ SA) of the carbon black 1 (C1) is preferably 80 m ² / g or more, more preferably 100 m ² / g or more from the viewpoint of weather resistance and conductivity. Also, N ₂ SA of the carbon black 1 (C1) is not more than 200 meters ² / g, preferably not more than 150m ² / g. When N ₂ SA of carbon black 1 (C1) exceeds 200 m ² / g, workability tends to deteriorate. In addition, N ₂ SA of carbon black in this specification is a value measured according to A method of JIS K6217.

  Carbon oil 1 (C1) has a dibutyl phthalate (DBP) oil absorption of preferably 60 ml / 100 g or more, more preferably 70 ml / 100 g or more, from the viewpoints of reinforcement and fracture characteristics. Further, the DBP oil absorption amount of carbon black 1 (C1) is preferably 130 ml / 100 g or less, and more preferably 120 ml / 100 g or less, from the viewpoints of elongation at break at break, fracture characteristics, and durability. In addition, the DBP oil absorption of carbon black in the present specification is a value determined by the measuring method of JIS K6217-4.

  The content of carbon black 1 (C1) is preferably 1 part by mass or more, more preferably 5 parts by mass or more, with respect to 100 parts by mass of the rubber component (A), from the viewpoint of the effect of containing carbon black. More preferred is part by mass or more. The content of carbon black 1 (C1) is preferably 30 parts by mass or less, and more preferably 20 parts by mass or less, from the viewpoint of low fuel consumption.

  Carbon black 2 (C2) is a so-called conductive carbon black, and according to the method for producing a rubber composition of the present invention containing carbon black 2 (C2), the fuel economy and conductivity are easily improved in a well-balanced manner. It is possible.

The nitrogen adsorption specific surface area (N ₂ SA) of the carbon black 2 (C2) is 900 m ² / g or more, preferably 1000 m ² / g or more, and more preferably 1050 m ² / g or more. When N ₂ SA is less than 900 m ² / g, sufficient conductivity tends not to be obtained. Also, N ₂ SA of the carbon black 2 (C2), the fuel economy, dispersibility, in view of the fracture properties and durability, preferably 1200 m ² / g or less, more preferably 1150m ² / g, 1100m ² / More preferably, it is g or less.

  The DBP oil absorption of carbon black 2 (C2) is preferably 300 ml / 100 g or more, more preferably 350 ml / 100 g or more, from the viewpoint of conductivity. Further, the DBP oil absorption of carbon black 2 (C2) is preferably 600 ml / 100 g or less, more preferably 500 ml / 100 g or less, and even more preferably 450 ml / 100 g or less, from the viewpoint of fracture characteristics and durability.

Examples of suitable commercial products of carbon black 2 (C2) include Lion Corporation's Lionite (N ₂ SA: 1052 m ² / g, DBP: 378 ml / 100 g), Lion Corporation's Ketjen Black EC300J (N ₂ SA: 800 m ² / g, DBP: 365 ml / 100 g), PRINTEX XE2B manufactured by Evonik (N ₂ SA: 1000 m ² / g, DBP: 420 ml / 100 g), and the like can be mentioned.

  The content of carbon black 2 (C2) is preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, with respect to 100 parts by mass of the rubber component (A), from the viewpoint of conductivity. More preferred is part by mass or more. Further, the content of carbon black 2 (C2) is preferably 20 parts by mass or less, and more preferably 15 parts by mass or less from the viewpoint of low heat build-up and cost.

Coupling agent (D)
The predetermined coupling agent (D) is a compound represented by the following chemical formula (1).
Formula _{(1) (C p H 2p} + 1 O) 3-Si- (CH 2) q -S-CO-C k H 2k + 1
(In chemical formula (1), p represents an integer of 1 to 3, q represents an integer of 1 to 5, and k represents an integer of 5 to 12.)

  P of the compound represented by the chemical formula (1) is an integer of 1 to 3 and preferably 2 from the viewpoint of reactivity with silica.

  Q of the compound represented by the chemical formula (1) is an integer of 1 to 5 and preferably an integer of 2 to 5 because rubber molecules and silica are bonded with an appropriate length and low heat build-up is improved. 3 is more preferable.

  K of the compound represented by the chemical formula (1) is an integer of 5 to 12, preferably an integer of 6 to 10, and more preferably 7, because the reactivity with the rubber molecule and the processability are compatible.

  As the coupling agent (D) represented by the chemical formula (1), 3-hexanoylthiopropyltriethoxysilane, 3-octanoylthiopropyltriethoxysilane, 3-decanoylthiopropyltriethoxysilane, 3-lauroylthio Propyltriethoxysilane, 2-hexanoylthioethyltriethoxysilane, 2-octanoylthioethyltriethoxysilane, 2-decanoylthioethyltriethoxysilane, 2-lauroylthioethyltriethoxysilane, 3-hexanoylthiopropyl Trimethoxysilane, 3-octanoylthiopropyltrimethoxysilane, 3-decanoylthiopropyltrimethoxysilane, 3-lauroylthiopropyltrimethoxysilane, 2-hexanoylthioethyltrimethoxysilane, 2-octano Lucio ethyltrimethoxysilane, 2- deca Neu thio ethyltrimethoxysilane, and the like can be illustrated 2- lauroyl thio ethyltrimethoxysilane, may be used alone or in combination of two or more. Among these, 3-octanoylthiopropyltriethoxysilane (NXT silane manufactured by Momentive) is particularly preferable in terms of availability and cost. Moreover, you may use together with common coupling agents other than the coupling agent (D) shown by Chemical formula (1).

  The total content of the coupling agent (D) represented by the chemical formula (1) is preferably 4 parts by mass or more with respect to 100 parts by mass of the total content of silica from the viewpoint of reaction with the filler and workability improvement effect. 5 parts by mass or more is more preferable, and 6 parts by mass or more is more preferable. Further, the total content of the coupling agent (D) is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and further preferably 9 parts by mass or less from the viewpoint of the silica dispersion effect commensurate with the increase in cost.

Vulcanizing chemical (E)
The vulcanizing agent (E) includes a vulcanizing agent (E1) and a vulcanization accelerator (E2). Further, vulcanizing chemicals generally used in the rubber industry such as vulcanization accelerating aids can also be used.

Vulcanizing agent (E1)
The vulcanizing agent (E1) is not particularly limited, and those commonly used in the tire industry can be used. From the point that the effect of the present invention can be obtained satisfactorily, sulfur is preferable, and powdered sulfur is more preferable. Sulfur may be used in combination with other vulcanizing agents. Other vulcanizing agents include, for example, Tachiroll V200 manufactured by Taoka Chemical Co., Ltd., DURALINK HTS (1,6-hexamethylene-sodium dithiosulfate dihydrate) manufactured by Flexis, and KA9188 manufactured by LANXESS. Examples thereof include vulcanizing agents containing sulfur atoms such as (1,6-bis (N, N′-dibenzylthiocarbamoyldithio) hexane) and organic peroxides such as dicumyl peroxide.

  The content of the vulcanizing agent (E1) is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more with respect to 100 parts by mass of the rubber component (A). Moreover, 15 mass parts or less are preferable and, as for content of a vulcanizing agent (E1), 5 mass parts or less are more preferable. When the content of the vulcanizing agent (E1) is within the above range, good tensile strength, wear resistance and heat resistance can be obtained.

Vulcanization accelerator (E2)
The vulcanization accelerator (E2) is not particularly limited, and those commonly used in the tire industry can be used. For example, thiazole vulcanization accelerators such as 2-mercaptobenzothiazole, dibenzothiazyl disulfide, N-cyclohexyl-2-benzothiazylsulfenamide; and thiuram additions such as tetramethylthiuram monosulfide and tetramethylthiuram disulfide. Sulfur accelerator; N-cyclohexyl-2-benzothiazole sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, N-oxyethylene-2- Sulfenamide vulcanization accelerators such as benzothiazole sulfenamide and N, N′-diisopropyl-2-benzothiazole sulfenamide; guanidines such as diphenylguanidine, diortolylguanidine, and orthotolylbiguanidine Examples thereof include vulcanization accelerators. Of these, sulfenamide-based vulcanization accelerators and guanidine-based vulcanization accelerators are preferable from the viewpoint of achieving both rubber elastic modulus and processability, and the reason is particularly excellent in balance between low fuel consumption and other rubber properties. To guanidine vulcanization accelerators are particularly preferred.

  Examples of the guanidine vulcanization accelerator include 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, dicatechol borate di-o-tolylguanidine salt, 1,3- Examples include di-o-cumenyl guanidine, 1,3-di-o-biphenyl guanidine, 1,3-di-o-cumenyl-2-propionyl guanidine, and the like. Among these, 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine, and 1-o-tolylbiguanide are more preferable because of high reactivity.

  The content of the vulcanization accelerator (E2) is preferably 0.1 parts by mass or more and more preferably 0.2 parts by mass or more with respect to 100 parts by mass of the rubber component (A). Further, the content of the vulcanization accelerator (E2) is preferably 5 parts by mass or less, and more preferably 3 parts by mass or less. When the content of the vulcanization accelerator (E2) is within the above range, a decrease in rubber elastic modulus and a decrease in fracture characteristics can be suppressed.

Other compounding agents In addition to the above components, the rubber composition for tires according to the present invention includes compounding agents conventionally used in the rubber industry, for example, reinforcing fillers other than plasticizer (F), silica and carbon black. Antiaging agent (G), antioxidant, stearic acid, wax and the like can be appropriately blended.

Plasticizer (F)
The rubber composition for tires according to the present invention preferably contains the plasticizer (F) because the processability is improved and the strength of the rubber can be increased. It does not specifically limit as a plasticizer (F), A general thing can be used in a tire industry, For example, oil, a liquid polymer, a liquid resin etc. are mentioned. Among these, oil is preferable because it can improve cost and workability in a balanced manner.

  Examples of the oil include process oil, vegetable oil and fat, animal fat and the like. Examples of the process oil include paraffinic process oil, naphthenic process oil, and aromatic process oil. Vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, palm oil, peanut oil, rosin, pine oil, pine tar, tall oil, corn oil, rice bran oil, sesame oil, olive oil, sunflower Oil, palm kernel oil, cocoon oil, jojoba oil, macadamia nut oil, safflower oil, tung oil and the like. Examples of animal fats include oleyl alcohol, fish oil, and beef tallow. Among them, a process oil is preferable because it is advantageous for processability, and a process oil (low PCA content) with a low content of polycyclic aromatic compound (PCA) is preferable because it reduces environmental burden. Process oil) is preferred.

  Low PCA content process oils include: Treated Distillate Aromatic Extract (TDAE), which is a re-extracted oil aromatic process oil, aroma substitute oil that is a mixed oil of asphalt and naphthenic oil, and mild extraction solvates (MES). ) And heavy naphthenic oils.

  The content with respect to 100 parts by mass of the rubber component (A) when oil is contained as the plasticizer (F) is preferably 2 parts by mass or more and more preferably 5 parts by mass or more from the viewpoint of workability improvement effect. The oil content is preferably 60 parts by mass or less, more preferably 50 parts by mass or less, and still more preferably 40 parts by mass or less from the viewpoint of the load in the process. The oil content in this specification does not include the oil-extended oil amount when the rubber component is an oil-extended product.

Anti-aging agent (G)
The anti-aging agent (G) is not particularly limited as long as it is a heat-resistant anti-aging agent, a weather-resistant anti-aging agent and the like and is usually used for rubber compositions. For example, naphthyl amine (phenyl-α-naphthyl amine) is used. Diphenylamine (octylated diphenylamine, 4,4′-bis (α, α′-dimethylbenzyl) diphenylamine, etc.), p-phenylenediamine (N-isopropyl-N′-phenyl-p-phenylenediamine, N Amine-based antioxidants such as-(1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, N, N'-di-2-naphthyl-p-phenylenediamine); 2,2,4 A quinoline anti-aging agent such as a polymer of trimethyl-1,2-dihydroquinoline; a monophenol (2,6-di-t-butyl-4- Phenols such as tilphenol and styrenated phenol), bis, tris, polyphenols (such as tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane) And anti-aging agents. Of these, amine-based anti-aging agents are preferable and p-phenylenediamine-based anti-aging agents are particularly preferable because they are excellent in ozone resistance.

  When the anti-aging agent (G) is contained, the content of 100 parts by weight of the rubber component (A) is preferably 0.5 parts by weight or more, and 1.0 part by weight or more from the viewpoint of ozone resistance and crack resistance. More preferred. Moreover, 10 mass parts or less are preferable from a viewpoint of discoloration prevention, and, as for content of anti-aging agent, 5 mass parts or less are more preferable.

Surfactant In one embodiment of the present invention, it is preferable to further contain a surfactant. By containing the surfactant, the dispersibility of the filler containing silica and carbon black can be improved, and discoloration due to aged deterioration of the obtained tire rubber composition can be prevented.

  Examples of the surfactant include metal soaps such as metal salts of organic acids and nonionic surfactants such as polyoxyalkylene derivatives, but are not particularly limited. These may be used alone or in combination.

  Preferred examples of the metal salt of an organic acid include a metal salt of a carboxylic acid. Examples of polyoxyalkylene derivatives include ether types such as polyoxyalkylene alkyl ethers, ester types such as polyoxyalkylene fatty acid esters, ether ester types such as polyoxyalkylene glycerin fatty acid esters, polyoxyalkylene fatty acid amides, and polyoxyalkylene alkyls. Examples thereof include nitrogen-containing types such as amines. Of these, polyoxyalkylene alkyl ethers and polyoxyalkylene fatty acid esters are particularly preferred in terms of the balance between low fuel consumption and other rubber properties.

  The content of the surfactant is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, with respect to 100 parts by mass of the rubber component (A), from the viewpoint of improving the dispersibility of silica. 6 parts by mass or more is more preferable, and 1.0 part by mass or more is most preferable. Further, the content of the surfactant is preferably 5.0 parts by mass or less, more preferably 4.0 parts by mass or less, from the viewpoints of handling stability, crack resistance, ozone resistance, and discoloration resistance, More preferred is less than or equal to parts by weight.

The volume specific resistivity of the rubber composition according to the present invention is preferably less than 1.0 × 10 ⁷ Ω · cm, because conductivity is obtained and noise and sparks due to static electricity can be prevented. 0.0 × 10 ⁶ Ω · cm or less is more preferable. In addition, the volume specific resistivity in this specification is a value calculated | required by the measuring method of JISK6271.

Method for Producing Tire Rubber Composition The method for producing a tire rubber composition of the present invention is characterized in that the kneading step is made into step X1, step X2 and step F. For each step, a known kneader can be used, and examples thereof include a Banbury mixer, a kneader, and an open roll.

  Specifically, part X or part of A, B, part of C1, D, and optionally part of E, step X1, step X1, kneaded product, remaining amount of B, C2, D A step X2 of kneading the remaining amount and optionally a part of E, and a kneading step including a step F of kneading the kneaded product of step X2 and the remaining amount of E are performed to obtain an unvulcanized rubber composition. It is a manufacturing method of the rubber composition for tires including the process to obtain. The obtained unvulcanized rubber composition can be further vulcanized (vulcanization step) to produce the tire rubber composition according to the present invention. The timing of adding and kneading other compounding agents such as plasticizer (F), anti-aging agent (G), zinc oxide, and stearic acid is not particularly limited, and any step of Step X1, Step X2, or Step F Or may be added in portions.

  The production method of the present invention is characterized in that the coupling agent (D) represented by the chemical formula (1) is divided and kneaded. Since the coupling agent (D) does not have a plurality of alkoxysilyl groups in the molecule, there is little aggregation between the coupling agents, and the mercapto group that reacts favorably with the polymer part becomes a fatty acid thioester, resulting in a rapid reaction. In addition, even in the kneading with divided charging as in the present invention, it is possible to form a uniform chemical bond between the filler and the polymer without losing the activity.

Process X1
In step X1, the total amount of rubber component (A), part or all of silica (B), carbon black 1 (C1), part of coupling agent (D), and optionally vulcanizing agent (E) The compounding agent containing a part is kneaded with a Banbury mixer. By this step, the filler is dispersed while forming a strong bond with the rubber component, particularly with the rubber component having a high affinity with the filler. Further, since the coupling agent (D) has the structure of the chemical formula (1), the thioester group is decomposed with kneading to gradually produce a highly active mercapto group. It can be dispersed to promote bonding with the polymer. In the conventional polysulfide silane, since sulfur is released even at this stage, the processability is lowered, the dispersion of the filler is hindered, and the activity of the coupling agent itself is also lowered, but it is represented by the chemical formula (1). Since the coupling agent (D) does not release sulfur, according to the production method of the present invention, kneading can be continued while maintaining processability.

  The addition amount of silica (B) in the step X1 is preferably 50% by mass or more of the total addition amount of silica (B) from the viewpoint of improving the silica kneading effect, sufficient dispersion of silica, and wear resistance, and 60% by mass. The above is more preferable, 70% by mass or more is further preferable, and 80% by mass or more is particularly preferable. The amount of silica (B) added in step X1 may be the total amount, but the amount of silica (B) added from the viewpoint of the effect of split introduction of silica in step X2, which will be described later, fuel efficiency, and wear resistance. Is preferably 95% by mass or less, and more preferably 90% by mass or less.

  The addition amount of the coupling agent (D) represented by the chemical formula (1) in the step X1 makes the reaction with the filler sufficient and can bring out the excellent workability improvement effect of the coupling agent (D). Therefore, 4 parts by mass or more is preferable, 5 parts by mass or more is more preferable, and 6 parts by mass or more is more preferable with respect to 100 parts by mass of silica (B) added in Step X1. Moreover, the addition amount of the coupling agent (D) represented by the chemical formula (1) in the step X1 is preferably 20 parts by mass or less, more preferably 10 parts by mass or less from the viewpoint of the silica dispersion effect commensurate with the increase in cost. 9 parts by mass or less is more preferable.

  The step of adding the plasticizer (F) is not particularly limited, but for the reason that the dispersion of the filler becomes good, in the step X1, it is possible to add 50% by mass or more of the total added amount of the plasticizer (F). Preferably, 70 mass% or more is more preferable, and 80 mass% or more is further more preferable. In addition, when the plasticizer (F) addition amount in process X1 is less than 100 mass%, it is preferable to add the remaining amount at process X2 because the dispersibility of the silica added at process X2 improves more.

  The surfactant is preferably added in the step X1 and / or the step X2 from the viewpoint of promoting the silica dispersion effect, further promoting the silica dispersion effect and suppressing the gelation of the coupling agent. It is preferable to add in the step X1 because it is possible.

Process X2
In step X2, a compounding agent containing the remaining amount of silica (B), carbon black 2 (C2), the remaining amount of coupling agent (D), and optionally a part of the vulcanizing agent (E) is added to step X1. Kneaded in addition to the kneaded product. If carbon black 1 (C1) and carbon black 2 (C2) are kneaded at the same time, the kneading share is excessively applied to carbon black 2, the network of conductive carbon black is broken, and the conductivity and wear resistance are reduced. However, by adding carbon black 2 (C2) after adding carbon black 1 (C1), that is, in step X2, the dispersion of carbon black 2 is not excessive and is moderate. A network can be formed. Furthermore, in the production method of the present invention, since the coupling agent (D) represented by the chemical formula (1) is dividedly added, it is possible to prevent early decrease in the activity of the coupling agent and maintain the workability in the entire kneading operation. it can.

  The addition amount of the coupling agent (D) represented by the chemical formula (1) in the step X2 can sufficiently react with the filler, and can bring out an excellent processability improvement effect of the coupling agent (D). For this reason, 4 parts by mass or more is preferable, 5 parts by mass or more is more preferable, and 6 parts by mass or more is more preferable with respect to 100 parts by mass of silica (B) added in Step X2. Moreover, the addition amount of the coupling agent (D) represented by the chemical formula (1) in the step X2 is preferably 20 parts by mass or less, more preferably 10 parts by mass or less from the viewpoint of the silica dispersion effect commensurate with the increase in cost. 9 parts by mass or less is more preferable. In addition, when all the silica (B) is added in the step X1, if only a part of the total addition amount of the coupling agent (D) is added in the step X1 and the remaining amount is added in the step X2. good.

  The step of adding the anti-aging agent (G) is not particularly limited, but it is preferable to add the whole amount in the step X2 from the viewpoint of work efficiency and prevention of the activity of the anti-aging agent during kneading.

  The discharge temperature of kneading in the step X1 and the step X2 is not particularly limited, but is preferably 142 ° C. or higher, more preferably 146 ° C. or higher, and further preferably 148 ° C. or higher. Further, the discharge temperature is preferably 170 ° C. or lower, and more preferably 160 ° C. or lower. When the discharge temperature of the kneading in the step X1 and the step X2 is within the above range, there is a tendency that a kneaded material in which the silica (B) is well dispersed can be efficiently obtained.

  Further, the maximum temperature during kneading in step X1 and step X2 is not particularly limited, but is preferably 140 ° C. or higher from the viewpoint that the coupling agent reacts sufficiently and a kneaded material in which silica is well dispersed can be obtained efficiently. 145 ° C. or higher is more preferable, and 150 ° C. or higher is more preferable. Moreover, in order to prevent rubber | gum burning, the maximum temperature during kneading | mixing has preferable 200 degrees C or less. If the temperature exceeds 150 ° C. in the normal kneading step, there is a possibility that problems such as gelation may occur. However, by adding the coupling agent (D) separately, the problem does not occur even when the kneading temperature becomes high. However, it is possible to promote the reaction of the coupling agent and promote the dispersion of the silica.

  The kneading time in step X1 and step X2 is not particularly limited, but is preferably 3.0 minutes or more and more preferably 4.0 minutes or more from the viewpoint of efficiently obtaining a kneaded material in which silica is well dispersed. 4.5 minutes or more is more preferable. Each kneading time is preferably 9 minutes or less, more preferably 8 minutes or less, and even more preferably 7 minutes or less.

  In one embodiment of the present invention, after reaching the maximum temperature in Step X1 and / or Step X2 and completing the kneading, the kneaded product is heated to 150 ° C. to 190 ° C., more preferably 150 to 180 ° C. Holding for 120 seconds is preferable because the reaction between the coupling agent and silica is completely performed.

Process F
In step F, after cooling the kneaded product obtained in step X2, a vulcanizing agent (E) containing a vulcanizing agent and a vulcanization accelerator is added and kneaded with an open roll or the like, and unvulcanized rubber It is a process of obtaining a composition.

  The vulcanization accelerator may be added all at once in the step F, but it is preferable to add a remaining amount in the step F after adding a part or the whole amount in the step X1 and / or the step X2. By adding a part or the whole amount in the step X1 and / or the step X2, the dispersion of the silica and the rubber component can be further promoted. In particular, it is more preferable to add the whole or part of the guanidine vulcanization accelerator in the step X1 and / or the step X2 because the dispersibility of silica can be further promoted.

  The kneaded product obtained in the step X2 is preferably cooled to 100 ° C. or lower, preferably 20 to 80 ° C.

  The kneading temperature in step F is preferably 110 ° C. or lower, and more preferably 100 ° C. or lower. When the discharge temperature exceeds 110 ° C., rubber burn (scorch) tends to occur easily. The lower limit of the kneading discharge temperature in the step F is not particularly limited, but is preferably 80 ° C. or higher.

  The kneading time in Step F is not particularly limited, but is usually 30 seconds or longer, preferably 1 to 30 minutes.

Vulcanization Step A vulcanized rubber composition can be obtained by vulcanizing the unvulcanized rubber composition obtained in Step F by a known method. The vulcanization temperature of the unvulcanized rubber composition is preferably 120 ° C. or higher, more preferably 140 ° C. or higher. The vulcanization temperature is preferably 200 ° C. or lower, and more preferably 180 ° C. or lower. When the vulcanization temperature is within the above range, the effect of the present invention can be obtained satisfactorily.

Rubber composition for tire The rubber composition for tire according to the present invention can be used for each member of a tire, and in particular, the rubber for tire improved in a good balance between low fuel consumption, wear resistance, wet grip performance and conductivity. Since it is a composition, it can be suitably used for treads, sidewalls, conductive structural members, and the like.

Tire The tire of the present invention can be produced by an ordinary method using the tire rubber composition according to the present invention. That is, the rubber composition for tires manufactured by the manufacturing method of the present invention is extruded in accordance with the shape of a tire member such as a tread of a tire at an unvulcanized stage and is combined with other tire members on a tire molding machine. The tire of the present invention can be manufactured by forming an unvulcanized tire by bonding and molding by a normal method, and heating and pressing the unvulcanized tire in a vulcanizer.

  The tire of the present invention may be a pneumatic tire or a non-pneumatic tire. Examples of pneumatic tires include passenger car tires, truck / bus tires, motorcycle tires, and high-performance tires. In addition, the high-performance tire in this specification is a tire that is particularly excellent in grip performance, and is a concept that includes a competition tire used in a competition vehicle. Examples of non-pneumatic tires include solid tires, airless tires, and track belts.

  As a preferred embodiment of the tire of the present invention, an airless tire having a tread composed of the rubber composition for tire according to the present invention can be mentioned. Airless tires tend to be inferior in electrical conductivity of the whole tire because there is no conductive member such as a steel cord or the wheels are made of resin, but the rubber composition according to the present invention is used for the tread. By using a conventional airless tire, good conductivity can be obtained.

  The present invention will be described based on examples, but the present invention is not limited to the examples.

Hereinafter, various chemicals used in Examples and Comparative Examples are shown together.
NR: TSR20
SBR1: Lancaess Buna SL4525-0 (styrene content: 25% by mass, non-oil extended, non-modified S-SBR)
SBR2: SBR produced in the following modified SBR production example (styrene content: 25 mass%, vinyl bond content: 55 mol%, non-oil-extended, terminal-modified S-SBR having an amino group and an alkoxysilyl group)
BR1: BR150B manufactured by Ube Industries, Ltd. (High cis BR, cis content: 97% by mass)
BR2: BR produced in the following modified BR production example (cis content: 97% by mass, terminal-modified high-cis BR having an amino group and an alkoxysilyl group)
Carbon black 1: Diamond black N220 manufactured by Mitsubishi Chemical Corporation (N ₂ SA: 114 m ² / g, DBP oil absorption: 115 ml / 100 g)
Carbon black 2: Lionite (conductive carbon black) manufactured by Lion Corporation (N ₂ SA: 1052 m ² / g, DBP oil absorption: 378 ml / 100 g, iron content: 1330 ppm)
Silica: Ultrasil VN3 manufactured by Evonik (N ₂ SA: 175 m ² / g)
Coupling agent 1: NXT manufactured by Momentive (3-octanoylthio-1-propyltriethoxysilane, p: 2, q: 3, k: 7 in chemical formula (1))
Coupling agent 2: Si69 (bis (3-triethoxysilylpropyl) tetrasulfide) manufactured by Degussa
Oil: VIVETEC 500 manufactured by H & R
Wax: Ozoace 0355 manufactured by Nippon Seiwa Co., Ltd.
Surfactant: Emulgen 123P manufactured by Kao Corporation (nonionic surfactant, polyoxyethylene lauryl ether)
Stearic acid: Beads manufactured by NOF Corporation Zinc stearate Zinc oxide: Zinc oxide manufactured by Hakusuitec Co., Ltd. Sulfur: Sulfur powder vulcanization accelerator manufactured by Tsurumi Chemical Co., Ltd. 1: Ouchi Shinsei Chemical Industry ( Noxeller NS (Nt-butyl-2-benzothiazylsulfenamide)
Vulcanization accelerator 2: Noxeller D (N, N'-diphenylguanidine) manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
Anti-aging agent: NOCRACK 6C (N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine) manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

Production examples of modified SBR and modified BR, and analysis methods are shown.
Modified SBR production example (SBR2)
A 5 L autoclave reactor fully purged with nitrogen was charged with 2750 g of cyclohexane, 50 g of tetrahydrofuran, 125 g of styrene and 375 g of butadiene, the temperature in the reactor was adjusted to 10 ° C., and a cyclohexane solution containing 5.8 mmol of n-butyllithium. And a polymerization reaction was carried out at 50 to 80 ° C. for 3 hours. Thereafter, a cyclohexane solution containing 4.96 mmol of N- [3- (trimethoxysilyl) -propyl] -N, N′-diethyl-N′-trimethylsilyl-ethane-1,2-diamine was added to the obtained polymer solution. In addition, the reaction was performed for 15 minutes. Thereafter, 2 g of 2,6-di-tert-butyl-p-cresol was added to the obtained polymer solution, and further steam stripping was performed by using hot water whose pH was adjusted to 9 with sodium hydroxide. After the solvent treatment, SBR2 was obtained by drying treatment with a hot roll adjusted to 110 ° C. As a result of analysis, Mw was 560,000, styrene content was 25 mass%, and vinyl bond content was 55 mol%.

Modified BR production example (BR2)
A 5 L autoclave reactor with sufficient nitrogen substitution was charged with 2400 g of cyclohexane and 300 g of 1,3-butadiene, a cyclohexane solution of neodymium versatate (0.09 mmol), a toluene solution of methylalumoxane (1.0 mmol), and hydrogenation. A catalyst prepared in advance by reacting and aging a toluene solution of diisobutylaluminum (3.5 mmol) and diethylaluminum chloride (0.18 mmol) and 1,3-butadiene (4.5 mmol) at 50 ° C. for 30 minutes. The polymerization reaction was carried out at 80 ° C. for 45 minutes. Next, while maintaining the reaction temperature at 60 ° C., a toluene solution of 3-glycidoxypropyltrimethoxysilane (4.5 mmol) is added, and the reaction is performed for 30 minutes, and the active terminal of the first conjugated diene polymer and The active ends of the two conjugated diene polymers were modified. Thereafter, a methanol solution containing 1.5 g of 2,4-di-tert-butyl-p-cresol was added, and the modified polymer solution was added to 20 L of an aqueous solution adjusted to pH 10 with sodium hydroxide. After removing the solvent for 2 hours, it was dried on a roll at 110 ° C. to obtain BR2. As a result of analysis, Mw was 350,000, cis content was 97%, and vinyl bond content was 1.1 mol%.

Measurement of weight average molecular weight Mw The weight average molecular weight Mw is a gel permeation chromatograph (GPC) (HLC-8220 manufactured by Tosoh Corp., column: HM-H manufactured by Tosoh Corp. (two in series), measurement temperature. : 40 ° C., carrier: tetrahydrofuran, flow rate: 0.6 ml / min, injection amount: 5 μl), and calculated by standard polystyrene conversion.

Measurement of styrene content, vinyl bond content, and cis content Using a JNM-ECA series NMR device manufactured by JEOL Ltd., structure identification was performed, and styrene content, vinyl bond content, and cis content were calculated. .

Comparative Examples 1-3
In accordance with the formulation shown in Table 2, various chemicals other than the vulcanizing agent (E1) and the vulcanization accelerator (E2) were kneaded in a 1.7 L Banbury mixer at a discharge temperature of 150 ° C. for 5 minutes (step X). Thereafter, the kneaded product of Step X, the vulcanizing agent (E1) and the vulcanization accelerator (E2) are kneaded at about 80 ° C. for 3 minutes using an open roll (Step F) to obtain an unvulcanized rubber composition. It was. Thereafter, test tires were produced in the same manner as in the Examples, and the following evaluations were performed. The results are shown in Table 1.

Examples 1 to 6 and Comparative Example 4
According to the formulation shown in Table 1 or 2, the various chemicals shown in Step X1 were kneaded for 5.0 minutes at a discharge temperature of 150 ° C. in a 1.7 L Banbury mixer (Step X1). Thereafter, the kneaded product was kept in the mixer for 1 minute so that the discharge temperature was 160 ° C. Next, the kneaded product of step X1 and the various chemicals shown in step X2 were kneaded for 30 seconds at 140 ° C. or higher in a 1.7 L Banbury mixer, and further kneaded for 3 minutes at a discharge temperature of 150 ° C. (step X2). . And the kneaded material of process X2 and the various chemicals shown in process F were kneaded for 3 minutes at about 80 ° C. using an open roll (process F) to obtain an unvulcanized rubber composition. The obtained unvulcanized rubber composition was molded into a tread shape, bonded together with other tire members on a tire molding machine, vulcanized for 35 minutes at 150 ° C. and 25 kgf, and a test tire (tire size: 195 / 65R15). The following evaluation was performed about the obtained tire for a test. The results are shown in Tables 1 and 2.

<Low fuel consumption test>
Using a rolling resistance tester, the rolling resistance when a test tire is run at a rim (15 × 6JJ), internal pressure (230 kPa), load (3.43 kN), speed (80 km / h) is measured and compared. Example 1 was shown as an index with 100 as the index. A larger index indicates better fuel efficiency.

<Abrasion resistance test>
Each test tire is mounted on all wheels of a real test vehicle (domestic FF vehicle, displacement: 2000cc), traveled on a dry asphalt road surface for 8000 km, the groove depth of the tire tread portion is measured, and the groove in the tire tread portion is measured. The travel distance when the depth decreased by 1 mm was calculated. By the following formula, the comparative example 1 was set to 100 and indicated as an index. It shows that it is excellent in abrasion resistance, so that an index | exponent is large.
(Abrasion resistance index) = (travel distance when the tire groove of each test tire is reduced by 1 mm)
/ (Travel distance when tire groove of Comparative Example 1 is reduced by 1 mm) × 100

<Wet grip performance test>
The braking distance from the initial speed of 100 km / h was measured on the wet road surface. By the following formula, the comparative example 1 was set to 100 and indicated as an index. It shows that it is excellent in wet grip performance, so that an index | exponent is large.
(Wet grip performance index) =
(Braking distance of comparative example 1) / (braking distance of each example) × 100

<Conductive performance test>
A test piece having a thickness of 2 mm and a size of 15 cm × 15 cm was cut out from each test tire, and the volume resistivity was measured under conditions of a voltage of 500 V, a temperature of 25 ° C., and a relative humidity of 50% using an electrical resistance measurement R8340A manufactured by ADVANTEST. did. The evaluation results are indicated by symbols according to the following criteria.
○: Volume resistivity is less than 1.0 × 10 ⁷ Ω · cm ×: Volume resistivity is 1.0 × 10 ⁷ Ω · cm or more

  From the results of Tables 1 and 2, the predetermined rubber component (A), silica (B), carbon black 1 (C1), carbon black 2 (C2), predetermined coupling agent (D), vulcanizing agent (E1) ), And a tire rubber composition containing the vulcanization accelerator (E2) can be produced in a well-balanced manner by improving fuel economy, wear resistance, wet grip performance, and conductivity by a predetermined manufacturing method. I understand.

Claims (12)

Rubber component (A) containing at least one selected from the group consisting of natural rubber and diene synthetic rubber, silica (B), carbon black 1 (C1) having a nitrogen adsorption specific surface area of 200 m ² / g or less, nitrogen adsorption ratio Contains carbon black 2 (C2) having a surface area of 900 m ² / g or more, a coupling agent (D) represented by the following chemical formula (1), and a vulcanizing agent (E) containing a vulcanizing agent and a vulcanization accelerator. A method for producing a rubber composition for a tire, comprising:
(Step X1) Step X1 of kneading part or all of A, B, part of C1, D, and optionally part of E,
(Step X2) The kneaded product of Step X1, the remaining amount of B, the remaining amount of C2, D, and optionally Step X2 of kneading a part of E, and (Step F) the kneaded material of Step X2, and E Process F for kneading the remaining amount
The manufacturing method of the rubber composition for tires containing this.
Formula _{(1) (C p H 2p} + 1 O) 3 -Si- (CH 2) q -S-CO-C k H 2k + 1
(In chemical formula (1), p represents an integer of 1 to 3, q represents an integer of 1 to 5, and k represents an integer of 5 to 12.) The production method according to claim 1, wherein the rubber component contains styrene-butadiene rubber and / or butadiene rubber having a functional group that reacts with silica. The production method according to claim 1 or 2, wherein the carbon black 2 (C2) has a DBP oil absorption of 300 ml / 100 g or more. The manufacturing method according to claim 1, wherein the rubber composition has a volume resistivity of less than 1.0 × 10 ⁷ Ω · cm. The production method according to any one of claims 1 to 4, wherein the addition amount of silica in the step X1 is 50 to 95 mass% of the total addition amount of silica. Furthermore, it is a method for producing a rubber composition containing a plasticizer,
The manufacturing method of any one of Claims 1-5 which knead | mixes 50 mass% or more of the total addition amount of a plasticizer in process X1. The manufacturing method according to any one of claims 1 to 6, wherein a maximum temperature in the step X1 and / or the step X2 is 140 ° C to 200 ° C. The manufacturing method of any one of Claims 1-7 including the process of hold | maintaining a kneaded material at 150-190 degreeC for 10 to 120 second after the kneading | mixing in process X1 and / or process X2 is complete | finished. The production method according to any one of claims 1 to 8, wherein a part or all of the vulcanization accelerator is kneaded in step X1 and / or step X2. Furthermore, it is a method for producing a rubber composition containing an anti-aging agent,
The manufacturing method of any one of Claims 1-9 which knead | mix an anti-aging agent in process X2. Furthermore, it is a method for producing a rubber composition containing a surfactant,
The manufacturing method of any one of Claims 1-10 which knead | mix a surfactant in process X1 and / or process X2. The tire which has a tire member comprised with the rubber composition for tires manufactured with the manufacturing method of any one of Claims 1-11.