Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/16—Nitrogen-containing compounds
  • C08K5/17—Amines; Quaternary ammonium compounds
  • C08K5/18—Amines; Quaternary ammonium compounds with aromatically bound amino groups
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
  • B60C1/0016—Compositions of the tread
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
  • B60C1/0025—Compositions of the sidewalls
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
  • C08J9/06—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a chemical blowing agent
  • C08J9/10—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a chemical blowing agent developing nitrogen, the blowing agent being a compound containing a nitrogen-to-nitrogen bond
  • C08J9/108—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a chemical blowing agent developing nitrogen, the blowing agent being a compound containing a nitrogen-to-nitrogen bond in a heterocyclic ring containing at least one carbon atom
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L7/00—Compositions of natural rubber
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2307/00—Characterised by the use of natural rubber
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2409/00—Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons
  • C08J2409/06—Copolymers with styrene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2201/00—Properties
  • C08L2201/08—Stabilised against heat, light or radiation or oxydation
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2203/00—Applications
  • C08L2203/14—Applications used for foams
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/80—Technologies aiming to reduce greenhouse gasses emissions common to all road transportation technologies
  • Y02T10/86—Optimisation of rolling resistance, e.g. weight reduction 

Definitions

• the present invention relates to a tire rubber composition, a tire rubber member, and a tire.
• a technique of introducing voids such as foamed pores into the rubber members of the tire tread that come into contact with the road surface For example, in Patent Document 1 below, a foamed rubber layer is provided on the tread of a tire, the foaming rate of the foamed rubber layer is set to 3% to 50%, and the foamed rubber layer is further provided with an affinity for the rubber component. and an inorganic compound powder having an average particle diameter of 10 ⁇ m or more.
• An object of the present invention is to provide a rubber composition for a tire that is suitable for use.
• a further object of the present invention is to provide a rubber member for a tire and a tire that are excellent in performance on ice and fracture resistance (in particular, fracture resistance after being exposed to high temperatures) while having voids.
• the essential configurations of the rubber composition for tires, the rubber member for tires, and the tire of the present invention for solving the above problems are as follows.
• R 1 and R 2 in the above general formula (1) are each independently a linear or cyclic monovalent saturated hydrocarbon group having 1 to 20 carbon atoms;
• a tire comprising a rubber member made of the rubber composition for tires according to any one of [1] to [3] or the rubber member for tires according to [4].
• the rubber composition for tires which can make the performance on ice of the rubber member for tires which has a void
• the rubber composition for tires, the rubber member for tires, and the tire of the present invention will be exemplified in detail below based on the embodiments thereof.
• the rubber composition for tires of the present invention comprises a rubber component, a void introduction agent, and the following general formula (1): and an amine anti-aging agent represented by [wherein R 1 and R 2 are each independently a monovalent saturated hydrocarbon group].
• the rubber composition for tires of the present invention is characterized in that the content of the amine anti-aging agent is 0.1 to 11 parts by mass with respect to 100 parts by mass of the rubber component.
• the rubber composition for a tire of the present invention contains a void-introducing agent, a rubber member obtained from the rubber composition has voids derived from the void-introducing agent and has excellent performance on ice.
• the amine antioxidant represented by the general formula (1) is added in an amount of 0.1 parts by mass or more per 100 parts by mass of the rubber component, thereby The aging resistance (ozone resistance) of the composition is improved, and the decrease in tensile stress, elongation at break (EB) and tensile strength (TB) of the rubber composition after exposure to high temperatures is suppressed. , the fracture resistance can be improved.
• the rubber composition for tires of the present invention it is possible to achieve both performance on ice and resistance to fracture (in particular, resistance to fracture after being exposed to high temperatures) of tire rubber members having voids. It is possible. Moreover, by applying the rubber composition for a tire of the present invention to a tread, it is possible to improve the fracture resistance and crack resistance of the tread which generates heat during running.
• the rubber composition for tires of the present invention comprises a rubber component, which provides rubber elasticity to the composition.
• a rubber component which provides rubber elasticity to the composition.
• diene rubber is preferable, and isoprene skeleton rubber, styrene-butadiene rubber (SBR), butadiene rubber (BR), and chloroprene rubber (CR) are more preferable.
• the isoprene-skeletal rubber is a rubber having isoprene units as a main skeleton, and specific examples thereof include natural rubber (NR), synthetic isoprene rubber (IR), and the like.
• the rubber component contains at least one selected from the group consisting of isoprene skeleton rubber, styrene-butadiene rubber, butadiene rubber, and chloroprene rubber
• the rubber composition has excellent rubber elasticity and is more suitable for tire applications. becomes.
• the rubber component contains at least one selected from the group consisting of isoprene skeleton rubber, styrene-butadiene rubber, butadiene rubber, and chloroprene rubber
• the effect of the present invention aging resistance by using an amine-based antioxidant property improvement effect, tensile stress after exposure to high temperature, elongation at break (EB) and tensile strength (TB) reduction suppression effect
• the embodiment containing a foaming agent as a void introducing agent the foaming agent
• the effect of improving the balance between the reaction rate and the vulcanization reaction rate of the rubber composition tends to appear remarkably.
• the content of diene rubber such as isoprene skeleton rubber, styrene-butadiene rubber, butadiene rubber and chloroprene rubber in the rubber component is preferably 80% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.
• the rubber component may be used alone or in a blend of two or more.
• the rubber composition for tires of the present invention contains a void introducing agent.
• the vulcanized rubber (rubber member) obtained by vulcanizing the rubber composition has voids on the surface or inside, or on the surface and inside.
• a tire using vulcanized rubber is flexible and easily adheres to an icy road surface, and water on the road surface is sucked into the voids on the tire surface and is easily removed from the icy and snowy road surface. Therefore, the tire to which the rubber composition for tires is applied can improve the braking performance on ice.
• the void-introducing agent examples include foaming agents, metal sulfates, thermally expandable microcapsules, porous cellulose particles, lignin derivatives, and the like. can be used. Among these, the foaming agent is preferable from the viewpoint of the on-ice performance of the tire.
• the content of the void-introducing agent in the rubber composition is not particularly limited, but from the viewpoint of obtaining a desired porosity and maintaining the fracture resistance, abrasion resistance, etc., 100 mass of the rubber component parts by weight, preferably 0.1 to 20 parts by weight, more preferably 0.3 to 10 parts by weight, and still more preferably 0.5 to 5 parts by weight.
• the content ratio of the void-introducing agent and the amine-based antioxidant described later is not particularly limited, but from the viewpoint of improving the crush resistance and performance on ice, the void-introducing agent and the amine-based antioxidant are mixed.
• (void introduction agent / amine anti-aging agent) is preferably 0.1 or more, more preferably 0.3 or more, still more preferably 0.5 or more, and preferably 10 or less, more preferably is 7 or less, more preferably 6 or less.
• the rubber composition contains a foaming agent as the void introduction agent, during vulcanization of the rubber composition, the foaming agent generates air bubbles in the vulcanized rubber (rubber member), and the vulcanized rubber becomes a foamed rubber.
• foamed rubber has flexibility, a tire surface using vulcanized rubber easily adheres to an icy road surface.
• the air bubbles create holes (foamed pores) originating from the air bubbles on the surface of the vulcanized rubber and the surface of the tire, which function as channels for draining water.
• foaming agent examples include azodicarbonamide (ADCA), dinitrosopentamethylenetetramine (DPT), dinitrosopentastyrenetetramine, benzenesulfonyl hydrazide derivatives, and p,p'-oxybisbenzenesulfonyl hydrazide.
• ADCA azodicarbonamide
• DPT dinitrosopentamethylenetetramine
• DPT dinitrosopentastyrenetetramine
• benzenesulfonyl hydrazide derivatives examples include p,p'-oxybisbenzenesulfonyl hydrazide.
• inorganic blowing agents such as (OBSH), carbonates such as ammonium carbonate, sodium carbonate, potassium carbonate, bicarbonates (bicarbonates) such as ammonium bicarbonate, sodium bicarbonate, potassium bicarbonate, nitroso sulfonylazo that generates nitrogen compound, N,N'-dimethyl-N,N'-dinitrosophthalamide, toluenesulfonyl hydrazide, p-toluenesulfonyl semicarbazide, p,p'-oxybisbenzenesulfonyl semicarbazide and the like.
• OBSH inorganic blowing agents
• azodicarbonamide ADCA
• dinitrosopentamethylenetetramine DPT
• inorganic foaming agents are preferably used from the viewpoint of manufacturing processability.
• foaming agents may be used individually by 1 type, and may be used in combination of 2 or more types.
• the content of the foaming agent in the rubber composition is not particularly limited, but is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, per 100 parts by mass of the rubber component.
• the metal sulfate protrudes from the surface of a rubber member obtained by vulcanizing the rubber composition (for example, the surface of a tire) and is said to be abrasive. Performs a claw function without penalty. Subsequent gradual exit of the metal sulfate from the rubber matrix then creates cavities that serve as storage volumes and passageways for the evacuation of the water film on the ice surface. Under these conditions, the contact between the surface of the rubber member [eg the surface of the tire (especially the surface of the tread)] and the ice is no longer lubricating, thus improving the coefficient of friction.
• metal sulfate examples include magnesium sulfate, calcium sulfate, barium sulfate, etc. Among these, magnesium sulfate is preferable.
• the metal sulfate is preferably micrometer-sized particles.
• the average particle size and median particle size are preferably 1 ⁇ m to 1 mm, and more preferably 2 ⁇ m to 800 ⁇ m.
• the target technical effect that is, formation of appropriate fine roughness
• the average particle size and median particle size are 1 mm or less, especially when the rubber composition is used as a tread, it suppresses the deterioration of aesthetics (suppresses the appearance of too clear particles on the tread surface) can be used), and the grip performance on melting ice is not likely to be impaired.
• the median particle size of the metal sulfate is more preferably between 2 ⁇ m and 500 ⁇ m, and most preferably between 5 ⁇ m and 200 ⁇ m. This particularly preferred particle size range appears to correspond to an optimum compromise between the desired surface roughness on the one hand and good contact of the rubber composition with the ice on the other hand.
• the content of the metal sulfate in the rubber composition is preferably 5 to 40 parts by mass, more preferably 10 to 35 parts by mass, based on 100 parts by mass of the rubber component. be.
• particle size analysis by mechanical sieving can be easily and preferably used.
• the operation consists of measuring a defined amount of sample (eg 200 g) on a vibrating table through different sieve diameters (eg according to a progression ratio equal to 1.26, 1000, 800, 630, 500, 400, . . . ). , 100, 80 and 63 ⁇ m meshes) and sieving for 30 minutes.
• the oversize collected in each sieve is weighed on a precision balance and the % oversize at each mesh diameter relative to the total mass of material is extrapolated from the weighing and finally the median particle size (or median diameter) or average particle size (or mean diameter) is calculated by known methods from the histogram of the particle size distribution.
• the heat-expandable microcapsules are constructed by enclosing a heat-expandable substance in a shell material made of a thermoplastic resin.
• the shell material of the thermally expandable microcapsules can be made of a nitrile polymer.
• the thermally expandable substance enclosed in the shell material of the microcapsules has the property of being vaporized or expanded by heat, and is exemplified by at least one selected from the group consisting of hydrocarbons such as isoalkanes and normal alkanes. be.
• Isoalkanes include isobutane, isopentane, 2-methylpentane, 2-methylhexane, 2,2,4-trimethylpentane, etc.
• Normal alkanes include n-butane, n-propane, n-hexane, Examples include n-heptane and n-octane.
• These hydrocarbons may be used alone or in combination.
• a preferred form of the thermally expandable substance is a hydrocarbon that is liquid at room temperature and a hydrocarbon that is gas at room temperature dissolved therein. By using such a mixture of hydrocarbons, it is possible to obtain a sufficient expansion force from a low temperature range to a high temperature range in the vulcanization forming temperature range (150° C. to 190° C.) of an unvulcanized tire.
• thermally expandable microcapsules examples include “EXPANCEL 091DU-80” and “EXPANCEL 092DU-120” manufactured by Expancel in Sweden, and “Matsumoto” manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd. Microsphere F-85D", “Matsumoto Microsphere F-100D”, etc. can be used.
• the content of the thermally expandable microcapsules in the rubber composition is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the rubber component.
• the rubber composition contains porous cellulose particles as the void introduction agent
• the porous cellulose particles are exposed on the surface of the rubber member obtained by vulcanizing the rubber composition (for example, the tire surface).
• the water on the icy road surface is absorbed by the porous cellulose particles. Therefore, water between the tire and the road surface can be removed by applying the rubber member to the tire.
• the presence of cellulose, which is a polysaccharide causes interaction between the tire and water on an ice-snow road surface, so the interaction between the tire and water can be further enhanced.
• the porous cellulose particles are cellulose particles having a porous structure with a porosity of 75 to 95%, and by adding them to the rubber composition, performance on ice can be remarkably improved.
• the porosity of the porous cellulose particles is 75% or more, the effect of improving performance on ice is excellent, and when the porosity is 95% or less, the strength of the particles can be increased.
• the porosity is more preferably 80-90%.
• the true specific gravity of cellulose is 1.5.
• the particle size of the porous cellulose particles is not particularly limited, those having an average particle size of 1000 ⁇ m or less are preferably used from the viewpoint of abrasion resistance.
• the lower limit of the average particle size is not particularly limited, it is preferably 5 ⁇ m or more.
• the average particle size is more preferably 100-800 ⁇ m, still more preferably 200-800 ⁇ m.
• porous cellulose particles As the porous cellulose particles, spherical particles having a major axis/minor axis ratio of 1 to 2 are preferably used.
• the use of particles having such a spherical structure improves the dispersibility in the rubber composition, which contributes to the improvement of performance on ice and the maintenance of wear resistance and the like.
• the ratio of major axis/minor axis is more preferably 1.0 to 1.5.
• the average particle size of the porous cellulose particles and the ratio of major axis/minor axis are obtained as follows. That is, an image is obtained by observing the porous cellulose particles with a microscope, and using this image, the long diameter and short diameter of the particle (when the long diameter and short diameter are the same, the length in a certain axial direction and the length perpendicular to this) The length in the axial direction) is measured for 100 particles and the average value is calculated to obtain the average particle size, and the average value of the values obtained by dividing the major axis by the minor axis. is obtained.
• porous cellulose particles are commercially available from Rengo Co., Ltd. as "Viscopearl", and are described in JP-A-2001-323095 and JP-A-2004-115284. It can be used preferably.
• the content of the porous cellulose particles in the rubber composition is preferably 0.3 to 20 parts by mass with respect to 100 parts by mass of the rubber component. When the content is 0.3 parts by mass or more, the effect of improving performance on ice can be enhanced. Abrasion reduction can be suppressed.
• the content of the porous cellulose particles is more preferably 1 to 15 parts by weight, still more preferably 3 to 15 parts by weight.
• lignin sulfonate is preferably used as the lignin derivative.
• the ligninsulfonate include alkali metal salts, alkaline earth metal salts, ammonium salts, and alcoholamine salts of ligninsulfonic acid, and at least one of these can be used.
• alkali metal salts and/or alkaline earth metal salts of lignosulfonic acid such as potassium, sodium, calcium, magnesium, lithium, and barium salts, and even mixed salts thereof. good.
• the content of the lignin derivative in the rubber composition is preferably 0.3 to 20 parts by mass with respect to 100 parts by mass of the rubber component. When the content is 0.3 parts by mass or more, the effect of improving performance on ice can be enhanced. Abrasion reduction can be suppressed.
• the content of the lignin derivative is more preferably 1 to 15 parts by mass, still more preferably 3 to 15 parts by mass.
• the rubber composition for tires of the present invention contains the amine anti-aging agent represented by the general formula (1).
• the amine antioxidant represented by the general formula (1) contains a phenylenediamine moiety like N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (antioxidant 6PPD). However, it differs from antiaging agent 6PPD in that it has no double bond other than the phenylenediamine moiety.
• the amine anti-aging agent represented by the general formula (1) improves the aging resistance (ozone resistance) of the rubber composition, and the tensile stress, elongation at break (EB) and tensile strength after exposure to high temperature. It has the effect of suppressing a decrease in strength (TB).
• R 1 and R 2 are each independently a monovalent saturated hydrocarbon group.
• R 1 and R 2 may be the same or different, but are preferably the same from the viewpoint of synthesis.
• the monovalent saturated hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and particularly preferably 6 and 7 carbon atoms.
• R 1 and R 2 in the general formula (1) are each independently a linear or cyclic monovalent having 1 to 20 carbon atoms. is preferably a saturated hydrocarbon group.
• Examples of the monovalent saturated hydrocarbon group include an alkyl group and a cycloalkyl group.
• the alkyl group may be linear or branched, and the cycloalkyl group may further include an alkyl group as a substituent. etc. may be combined.
• alkyl group examples include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, 1,2-dimethylbutyl group, 1,3- dimethylbutyl group, 2,3-dimethylbutyl group, n-pentyl group, isopentyl group, neopentyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,2 -dimethylpentyl group, 1,3-dimethylpentyl group, 1,4-dimethylpentyl group, 2,3-dimethylpentyl group, 2,4-dimethylpentyl group, 3,4-dimethylpentyl group, n-hexyl group, Examples include 1-methylhexyl group, 2-methylhexyl group, various
• 1,4-dimethylpentyl group is preferred.
• the cycloalkyl group include a cyclopentyl group, a methylcyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, etc.
• a cyclohexyl group is preferred.
• amine antioxidant represented by the general formula (1) examples include N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (antiaging agent 77PD), N, N'-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine, N,N'-dicyclohexyl-p-phenylenediamine (antiaging agent CCPD) and the like, among these, N,N' -Bis(1,4-dimethylpentyl)-p-phenylenediamine (antiaging agent 77PD), N,N'-dicyclohexyl-p-phenylenediamine (CCPD) are preferred, N,N'-bis(1,4- Dimethylpentyl)-p-phenylenediamine (antiaging agent 77PD) is particularly preferred.
• the amine anti-aging agents may be used singly or in combination of two or more.
• the content of the amine anti-aging agent is 0.1 to 11 parts by mass with respect to 100 parts by mass of the rubber component. If the content of the amine anti-aging agent is less than 0.1 parts by mass with respect to 100 parts by mass of the rubber component, the rubber composition cannot sufficiently ensure the aging resistance and is exposed to high temperatures. It is not possible to sufficiently suppress the decrease in the tensile stress, elongation at break (EB) and tensile strength (TB) of the rubber composition after it has been cured.
• EB elongation at break
• TB tensile strength
• a foaming agent as a void introduction agent
• the reaction speed of the foaming agent and the rubber composition The effect of improving the balance with the vulcanization reaction rate of the product is insufficient.
• the content of the amine anti-aging agent exceeds 11 parts by mass with respect to 100 parts by mass of the rubber component, the adverse effect on rubber physical properties other than aging resistance (heat build-up, etc.) increases, resulting in tire applications. become unsuitable.
• the content of the amine antioxidant is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, relative to 100 parts by mass of the rubber component. 10 parts by mass or less is preferable, and 8 parts by mass or less is more preferable with respect to 100 parts by mass of the rubber component, from the viewpoint of the effect on the rubber.
• the rubber composition for tires of the present invention may contain a quinoline antioxidant.
• the quinoline anti-aging agent is an anti-aging agent having a quinoline moiety or a derivative thereof (such as a dihydroquinoline moiety).
• the quinoline anti-aging agent improves the aging resistance (ozone resistance) of the rubber composition, and reduces the retention rate of elongation at break (EB) and tensile strength (TB) after exposure to high temperatures. It has an inhibitory action.
• the quinoline antioxidant preferably has a dihydroquinoline moiety, more preferably a 1,2-dihydroquinoline moiety.
• Specific examples of the quinoline antioxidant include a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline (antioxidant TMDQ), 6-ethoxy-2,2,4-trimethyl-1 ,2-dihydroquinoline, 6-anilino-2,2,4-trimethyl-1,2-dihydroquinoline and the like.
• the quinoline antioxidant preferably contains a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline (antiaging agent TMDQ).
• a quinoline anti-aging agent containing a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline is highly effective in improving the aging resistance of a rubber composition, and is said to be less likely to discolor the rubber composition. It also has advantages.
• the polymer of 2,2,4-trimethyl-1,2-dihydroquinoline includes dimers, trimers and tetramers of 2,2,4-trimethyl-1,2-dihydroquinoline. mentioned.
• the content of the quinoline antioxidant is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the rubber component.
• the content of the quinoline antioxidant is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component, the aging resistance of the rubber composition is improved, and the rubber composition after being exposed to high temperatures It is possible to further suppress the decrease in elongation at break (EB) and tensile strength (TB).
• EB elongation at break
• TB tensile strength
• the content of the quinoline antioxidant is 5 parts by mass or less with respect to 100 parts by mass of the rubber component, adverse effects on rubber physical properties other than aging resistance (heat buildup, etc.) can be suppressed. , more suitable for tire applications.
• the content of the quinoline antioxidant is more preferably 0.3 parts by mass or more, still more preferably 0.5 parts by mass or more, with respect to 100 parts by mass of the rubber component. From the viewpoint of affecting other rubber physical properties, it is more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less, relative to 100 parts by mass of the rubber component.
• the tire rubber composition of the present invention may contain a foaming aid.
• a foaming aid when the rubber composition contains a foaming agent as the void introduction agent, it preferably contains a foaming aid.
• the foaming aid include urea, zinc stearate, zinc benzenesulfinate, and zinc white. Among these, urea is widely known. These may be used individually by 1 type, and may be used in combination of 2 or more types. By using the foaming aid together, it is possible to accelerate the foaming reaction, increase the degree of completion of the reaction, and suppress unnecessary deterioration over time.
• the total content of the foaming agent and the foaming assistant is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the rubber component.
• the total content of the foaming agent and the foaming assistant is 1 part by mass or more, the rubber composition can be sufficiently foamed during vulcanization, and the foaming rate of the vulcanized rubber can be maintained at a high level.
• the total content of the foaming agent and the foaming aid is 30 parts by mass or less, the decrease in foaming rate can be suppressed.
• the total content of the foaming agent and the foaming assistant is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, with respect to 100 parts by mass of the rubber component.
• the total content of the foaming agent and the foaming assistant is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, with respect to 100 parts by mass of the rubber component.
• the mass ratio of the foaming agent and the foaming aid is preferably 1:1.1 to 1:3.3.
• the mass ratio (foaming agent:foaming aid) is in the range of 1:1.1 to 1:3.3, the rubber composition is sufficiently foamed during vulcanization, and the foaming ratio of the vulcanized rubber is improved.
• the mass ratio of the foaming agent and the foaming aid (foaming agent:foaming aid) is preferably 1:1.2 or more, more preferably 1:1.3 or more. .
• the mass ratio of the foaming agent and the foaming aid is preferably 1:3.2 or less, more preferably 1:3.1 or less. , more preferably 1:2.9 or less, even more preferably 1:2.7 or less, even more preferably 1:2.5 or less, and particularly preferably 1:2.3 or less.
• the content of the foaming aid is preferably in the range of 4 to 14 parts by mass with respect to 100 parts by mass of the rubber component, from the viewpoint of the foaming rate of the vulcanized rubber and the performance on ice of the tire.
• a range of 14 parts by mass is more preferable.
• the rubber composition may contain an organic acid, if necessary.
• the SP value of the organic acid is preferably 9.15 to 16.0 (cal/cm 3 ) 1/2 .
• the organic acid balances the decomposition/foaming reaction speed of the foaming agent and the vulcanization reaction speed of the rubber composition, thereby improving the foaming rate of the vulcanized rubber. It has the effect of causing Therefore, by blending the organic acid into the rubber composition, the decomposition/foaming reaction of the foaming agent is promoted while maintaining good workability of the rubber composition.
• the expansion rate of the vulcanized rubber can be improved, and by applying the rubber composition to a tire, the performance on ice of the tire can be improved.
• the SP value of the organic acid is less than 9.15 (cal/cm 3 ) 1/2 , the decomposition of the blowing agent may not be sufficiently accelerated, and the SP value of the organic acid is 16.0 ( cal/cm 3 )
• it exceeds 1/2 the adhesion of the rubber composition containing the organic acid increases, and the rubber composition adheres to production equipment such as rolls during the production of the rubber composition. The workability of the composition may deteriorate.
• the SP value of the organic acid is preferably 10.5 to 14.3 (cal/cm 3 ) 1/2 .
• the SP value of the organic acid is 10.5 (cal/cm 3 ) 1/2 or more, the effect of promoting the decomposition of the foaming agent is further enhanced, and the SP value of the organic acid is 14.3 (cal /cm 3 )
• it is 1/2 or less, the adhesion of the rubber composition containing an organic acid can be further reduced, and the workability of the rubber composition is further improved.
• Stearic acid which is commonly used as a vulcanization aid for rubber compositions, has an SP value of 9.12 (cal/cm 3 ) 1/2 and is less effective in accelerating the decomposition of the foaming agent.
• the SP value (solubility parameter) of an organic acid is calculated according to the Fedors method.
• the organic acid may be any of monocarboxylic acid, dicarboxylic acid, tricarboxylic acid, and the like, and may be aliphatic or aromatic. You may have functional groups other than a carboxyl group, such as a saturated group.
• the organic acid one having an aromatic ring (aromatic) is preferable, and a monocarboxylic acid is preferable.
• the organic acid has an aromatic ring, the adhesion of the rubber composition can be further reduced, the workability of the rubber composition is further improved, and the adhesion to production equipment such as rolls is further reduced.
• Palmitic acid etc. are mentioned as said aliphatic monocarboxylic acid.
• the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.
• the aromatic monocarboxylic acid include benzoic acid and salicylic acid.
• the aromatic dicarboxylic acid include phthalic acid.
• organic acids having functional groups other than carboxyl groups include tartaric acid, malic acid, maleic acid, glycolic acid, ⁇ -ketoglutaric acid and the like. The said organic acid may be used individually by 1 type, and may be used in combination of 2 or more type.
• benzoic acid it is particularly preferable to use benzoic acid as the organic acid.
• benzoic acid is blended into the rubber composition, the adhesion of the rubber composition can be further reduced, the workability of the rubber composition is further improved, and adhesion to manufacturing equipment such as rolls becomes even more difficult.
• the content of the organic acid is 0.1 to 7 parts by mass with respect to 100 parts by mass of the rubber component, from the viewpoint of the workability of the rubber composition, the foaming rate of the vulcanized rubber, and the performance on ice of the tire. is preferable, 1.5 to 7 parts by mass is more preferable, and 3 to 7 parts by mass is even more preferable.
• the total content of the foaming agent and the organic acid is 3 parts by mass or more and less than 15 parts by mass with respect to 100 parts by mass of the rubber component, from the viewpoint of the foaming rate of the vulcanized rubber and the performance on ice of the tire. more preferably 5 parts by mass or more and less than 15 parts by mass, and even more preferably 7 parts by mass or more and less than 15 parts by mass.
• the mass ratio of the foaming agent and the organic acid is in the range of 1:0.5 to 1:1.5 from the viewpoint of the foaming rate of the vulcanized rubber and the performance on ice of the tire. and more preferably in the range of 1:0.7 to 1:1.3.
• the rubber composition for tires of the present invention preferably further contains wax.
• the aging resistance (ozone resistance) of the rubber composition is further improved.
• the wax include paraffin wax and microcrystalline wax.
• the content of the wax is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the rubber component.
• the wax content is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component, the aging resistance of the rubber composition is further improved.
• the wax content is 5 parts by mass or less with respect to 100 parts by mass of the rubber component, the effect on rubber physical properties other than aging resistance is small.
• the content of the wax is more preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, with respect to 100 parts by mass of the rubber component. From the viewpoint of influence, it is more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less with respect to 100 parts by mass of the rubber component.
• the tire rubber composition of the present invention preferably contains sulfur.
• sulfur When the rubber composition contains sulfur, it becomes vulcanizable, and the fracture resistance (in particular, elongation at break (EB) and tensile strength (TB)) of the rubber composition is improved.
• sulfur various types of sulfur can be used, but ordinary sulfur (soluble sulfur (powder sulfur), etc.) is preferable to insoluble sulfur, and oil treated sulfur, etc. are also preferable.
• insoluble sulfur is sulfur insoluble in carbon disulfide (amorphous polymeric sulfur)
• soluble sulfur (powder sulfur) is sulfur soluble in carbon disulfide.
• the sulfur content is preferably in the range of 0.1 to 10 parts by mass, more preferably in the range of 1 to 5 parts by mass, per 100 parts by mass of the rubber component. If the sulfur content is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component, the fracture resistance of the vulcanized rubber can be secured, and if it is 10 parts by mass or less with respect to 100 parts by mass of the rubber component rubber elasticity can be sufficiently ensured.
• the rubber composition for tires of the present invention contains, in addition to the above-described rubber component, void introduction agent, amine-based antioxidant, quinoline-based antioxidant, foaming aid, organic acid, wax, and sulfur, if necessary
• various components commonly used in the rubber industry such as fillers (silica, carbon black, calcium carbonate, etc.), silane coupling agents, softeners, processing aids, resins, surfactants, SP values 9.15 to 16.0 (cal /cm ) It may be appropriately selected and contained within a range that does not impair the object of the invention. Commercially available products can be suitably used as these compounding agents.
• the amine anti-aging agent represented by the general formula (1) may be supported on any carrier.
• the amine anti-aging agent represented by the above general formula (1) may be supported on inorganic fillers such as silica and calcium carbonate.
• the amine anti-aging agent represented by the general formula (1) may form a masterbatch together with the rubber component.
• the rubber component used in forming the masterbatch is not particularly limited, and may be diene rubber such as natural rubber (NR), ethylene-propylene-diene rubber (EPDM), or the like.
• the amine anti-aging agent represented by the general formula (1) may be a salt with an organic acid.
• the organic acid used for forming the salt is not particularly limited, but stearic acid and the like can be mentioned.
• the method for producing the rubber composition is not particularly limited. , kneading, heating, extrusion, or the like. Further, vulcanized rubber can be obtained by vulcanizing the obtained rubber composition.
• the kneading conditions are not particularly limited, and various conditions such as the input volume of the kneading device, the rotation speed of the rotor, the ram pressure, the kneading temperature, the kneading time, the type of the kneading device, etc. It can be selected as appropriate.
• the kneading device include Banbury mixers, intermixes, kneaders, rolls, etc., which are usually used for kneading rubber compositions.
• heating conditions there are no particular restrictions on the heating conditions, and various conditions such as the heating temperature, heating time, and heating device can be appropriately selected according to the purpose.
• the heating device include a heating roll machine or the like which is usually used for heating the rubber composition.
• the extrusion conditions are also not particularly limited, and various conditions such as extrusion time, extrusion speed, extrusion equipment, and extrusion temperature can be appropriately selected according to the purpose.
• the extrusion device include an extruder or the like that is usually used for extrusion of a rubber composition.
• the extrusion temperature can be determined appropriately.
• a molding vulcanizer with a mold used for vulcanization of a rubber composition can be used.
• the temperature is, for example, about 100 to 190.degree.
• the tire rubber member of the present invention is a tire rubber member having voids, comprising a rubber component and the following general formula (1): [Wherein, R 1 and R 2 are each independently a monovalent saturated hydrocarbon group] and an amine antioxidant represented by It is characterized by being 0.1 to 11 parts by mass with respect to 100 parts by mass of the rubber component.
• the rubber member for a tire of the present invention Since the rubber member for a tire of the present invention has voids, it has excellent performance on ice. Further, the rubber member for a tire of the present invention contains 0.1 parts by mass or more of the amine antioxidant represented by the general formula (1) with respect to 100 parts by mass of the rubber component, thereby improving aging resistance. (Ozone resistance) is improved, and reduction in tensile stress, elongation at break (EB) and tensile strength (TB) after exposure to high temperature is suppressed, and fracture resistance can be improved. Therefore, the rubber member for a tire of the present invention is excellent in performance on ice and fracture resistance (especially fracture resistance after being exposed to high temperatures) while having voids. Further, by applying the rubber member for a tire of the present invention to a tread, it is possible to improve the destruction resistance and crack resistance of the tread which generates heat during running.
• the rubber member for tires of the present invention can be formed, for example, from the rubber composition for tires of the present invention described above.
• voids can be formed by heating, etc., thereby producing a tire rubber member having voids.
• the pore-introducing agent contains a metal sulfate, porous cellulose particles, or a lignin derivative
• the metal sulfate, the porous cellulose particles, or the lignin derivative gradually withdraws from the rubber matrix during use, thereby generating cavities.
• a tire rubber member having voids can be obtained.
• the rubber component contained in the rubber member for tires of the present invention and the amine antioxidant represented by the general formula (1) include the rubber component used in the rubber composition for tires described above, and the rubber component represented by the general formula (1).
• the amine anti-aging agents represented can be used, and their contents, blending ratios, etc. are also the same.
• the rubber member for tires of the present invention may appropriately contain various compounding agents that can be compounded in the rubber composition for tires described above.
• a tire of the present invention is characterized by comprising a rubber member made of the rubber composition for a tire described above or the rubber member for a tire described above. Since the tire of the present invention includes a rubber member made of the above-described rubber composition for a tire or the above-described rubber member for a tire, while having voids, the tire has performance on ice and fracture resistance (in particular, exposure to high temperatures). (destruction resistance after being broken).
• Suitable examples of the rubber member include tread rubber that constitutes the tread of a tire.
• a tire having the rubber member in the tread is excellent in fracture resistance and crack resistance.
• the tire of the present invention may be obtained by vulcanizing after molding using an unvulcanized rubber composition, or using a semi-vulcanized rubber that has undergone a pre-vulcanization step or the like. After molding, it may be obtained by further vulcanization.
• the tire of the present invention is preferably a pneumatic tire, and the gas to be filled in the pneumatic tire may be normal air or oxygen partial pressure-adjusted air, or an inert gas such as nitrogen, argon, or helium. can be used.
• Rubber compositions were produced according to the formulations shown in Tables 1 and 2.
• the foaming rate of the obtained rubber composition was measured by the following method, and the performance on ice and the retention rate of tensile stress (M300) at 300% elongation after deterioration were evaluated. Furthermore, the ice performance and fracture resistance were comprehensively evaluated from the total value of the index value of the ice performance and the retention rate (%) of the tensile stress (M300) at 300% elongation. The results are shown in Tables 1 and 2.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Materials Engineering (AREA)
• Compositions Of Macromolecular Compounds (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=86241476

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (21)

Family Cites Families (3)

• 2022
  • 2022-10-18 WO PCT/JP2022/038824 patent/WO2023079949A1/ja not_active Ceased
  • 2022-10-18 EP EP22889770.8A patent/EP4428189A4/en active Pending
  • 2022-10-18 US US18/698,463 patent/US20240327625A1/en active Pending
  • 2022-10-18 JP JP2023557933A patent/JPWO2023079949A1/ja active Pending

Patent Citations (21)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events