JP2013087185A - Rubber composition and tire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition which has the improved dispersibility of silica in the rubber composition, can improve the viscosity deterioration of an un-vulcanized rubber, and has improved processability, and to provide a tire using the same.SOLUTION: The rubber composition is characterized by compounding at least one rubber component selected from natural rubber and/or dienic synthetic rubbers with a white filler, and at least one compound represented by formula (I) [wherein, at least one of R-Ris a group represented by RCONHA-, the remainder of R-Rare groups represented by formula (III) (wherein, Ris 1-6C alkylene; n is an average addition molar number of 0-5; and m is an integer of 1-3)].

Description

  The present invention relates to a rubber composition and a tire using the rubber composition, and more specifically, a rubber that improves the dispersibility of silica in the rubber composition, can improve the viscosity reduction of unvulcanized rubber, and has good processability. The present invention relates to a composition and a tire using the composition.

  With the recent social demands for energy saving, silica is often used as a filler to achieve both low heat buildup of tire rubber compositions and grip on wet roads for the purpose of saving fuel consumption in automobiles. Yes.

  The silica used tends to aggregate particles due to hydrogen bonding of silanol groups, which are surface functional groups, and it is necessary to lengthen the kneading time in order to improve the dispersion of the silica in the rubber. Further, since the silica is not sufficiently dispersed in the rubber, the rubber composition has a high Mooney viscosity, and has disadvantages such as inferior processability such as extrusion. Furthermore, since the surface of the silica particles is acidic, the basic substance used as a vulcanization accelerator is adsorbed, the rubber composition is not sufficiently vulcanized, and the storage elastic modulus does not increase. Was. For this reason, there has been a demand for improvements in processability and the like in silica-containing rubber compositions.

  Conventionally, as a technique for improving various physical properties and the like in a silica-containing rubber composition, for example, in order to provide a rubber composition having improved heat generation and wear resistance and a pneumatic tire using the same, (A) Natural rubber and / or diene synthetic rubber, (B) a rubber composition containing an inorganic filler (silica) based on silicic acid and (C) a specific amine addition salt, and a pneumatic tire using the rubber composition ( For example, see Patent Document 1 of the applicant of the present application).

  However, the present situation is that realization of the effect of reducing the viscosity of unvulcanized rubber is desired.

WO97 / 035461 pamphlet (claims, examples, etc.)

  The present invention intends to solve the above-mentioned problems of the prior art, and improves the dispersibility of silica in the rubber composition and can improve the viscosity reduction of the unvulcanized rubber. It is an object of the present invention to provide a product, a tire using the same, and a method for reducing the viscosity of unvulcanized rubber.

  As a result of intensive investigations in view of the above-mentioned problems of the prior art, the present inventors have found that a white filler and a specific compound are used for at least one rubber component selected from natural rubber and / or diene-based synthetic rubber. By blending at least one of the above, it was found that the above rubber composition, a tire using the rubber composition, and a method for reducing the viscosity of unvulcanized rubber were obtained, and the present invention was completed.

〔上記式（Ｉ）中において、Ｒ_１〜Ｒ_３のうち少なくとも１つが、下記式（II）で表される基を表し、残余のＲ_１〜Ｒ_３が、下記式（III）で表される基を表す。〕

〔式（II）中、Ｒ_４は、炭素数１〜２４のアルキル基又はアルケニル基を表し、該アルキル基及びアルケニル基は直鎖状、分枝鎖状及び環状の何れでもよく、また、Ａは炭素数１〜６のアルキレン基である。〕

〔式（III）中、Ｒ_５は、炭素数１〜６のアルキレン基であり、また、ｎは平均付加モル数を意味し、０〜５となる数であり、ｍは１〜３となる整数である。〕
（２） 前記ゴム成分１００質量部に対し、白色充填剤を５〜２００質量部、上記式（Ｉ）で表される化合物の少なくとも一種を０．５〜１５質量部配合してなることを特徴とする上記（１）に記載のゴム組成物。
（３）前記一般式（１）で表される化合物が、Ｎ−ラウロイルアミノプロピル−Ｎ，Ｎ−ジメチルアミン、Ｎ−ラウロイルアミノエチル−Ｎ，Ｎ−ジエチルアミン、Ｎ−パルミトイルアミノプロピル−Ｎ，Ｎ−ジメチルアミン、Ｎ−パルミトイルアミノエチル−Ｎ，Ｎ−ジエチルアミン、Ｎ−ステアロイルアミノプロピル−Ｎ，Ｎ−ジメチルアミン、及びＮ−ステアロイルアミノエチル−Ｎ，Ｎ−ジエチルアミンからなる群から選ばれる１種以上である上記（１）又は（２）に記載のゴム組成物。
（４） 更に、シランカップリング剤を配合することを特徴とする上記（１）〜（３）の何れか一つに記載のゴム組成物。
（５） 上記（１）〜（４）の何れか一つに記載のゴム組成物をタイヤ部材に用いてなることを特徴とするタイヤ。
（６） 天然ゴム及び／又はジエン系合成ゴムから選択される少なくとも一種のゴム成分に対して、白色充填剤と、下記式（Ｉ）で表される化合物の少なくとも一種とを配合する、未加硫ゴムの粘度低減方法。

〔上記式（Ｉ）中において、Ｒ_１〜Ｒ_３のうち少なくとも１つが、下記式（II）で表される基を表し、残余のＲ_１〜Ｒ_３が、下記式（III）で表される基を表す。〕

〔式（II）中、Ｒ_４は、炭素数１〜２４のアルキル基又はアルケニル基を表し、該アルキル基及びアルケニル基は直鎖状、分枝鎖状及び環状の何れでもよく、また、Ａは炭素数１〜６のアルキレン基である。〕

〔式（III）中、Ｒ_５は、炭素数１〜６のアルキレン基であり、また、ｎは平均付加モル数を意味し、０〜５となる数であり、ｍは１〜３となる整数である。〕 That is, the present invention resides in the following (1) to (6).
(1) A white filler and at least one compound represented by the following formula (I) are blended with at least one rubber component selected from natural rubber and / or diene synthetic rubber. A rubber composition characterized by the above.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]
(2) The rubber component is blended in an amount of 5 to 200 parts by weight of a white filler and 0.5 to 15 parts by weight of at least one compound represented by the above formula (I) with respect to 100 parts by weight of the rubber component. The rubber composition according to (1) above.
(3) The compound represented by the general formula (1) is N-lauroylaminopropyl-N, N-dimethylamine, N-lauroylaminoethyl-N, N-diethylamine, N-palmitoylaminopropyl-N, N. One or more selected from the group consisting of dimethylamine, N-palmitoylaminoethyl-N, N-diethylamine, N-stearoylaminopropyl-N, N-dimethylamine, and N-stearoylaminoethyl-N, N-diethylamine The rubber composition as described in (1) or (2) above.
(4) The rubber composition as described in any one of (1) to (3) above, further comprising a silane coupling agent.
(5) A tire comprising the rubber composition according to any one of (1) to (4) above as a tire member.
(6) A white filler and at least one compound represented by the following formula (I) are blended with at least one rubber component selected from natural rubber and / or diene-based synthetic rubber. A method for reducing the viscosity of vulcanized rubber.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]

  According to the present invention, it is possible to improve the dispersibility of silica in the rubber composition, improve the viscosity reduction of the unvulcanized rubber and improve the processability, a pneumatic tire using the rubber composition, and A method for reducing the viscosity of unvulcanized rubber is provided.

〔上記式（Ｉ）中において、Ｒ_１〜Ｒ_３のうち少なくとも１つが、下記式（II）で表される基を表し、残余のＲ_１〜Ｒ_３が、下記式（III）で表される基を表す。〕

〔式（II）中、Ｒ_４は、炭素数１〜２４のアルキル基又はアルケニル基を表し、該アルキル基及びアルケニル基は直鎖状、分枝鎖状及び環状の何れでもよく、また、Ａは炭素数１〜６のアルキレン基である。〕

〔式（III）中、Ｒ_５は、炭素数１〜６のアルキレン基であり、また、ｎは平均付加モル数を意味し、０〜５となる数であり、ｍは１〜３となる整数である。〕 Hereinafter, embodiments of the present invention will be described in detail.
The rubber composition of the present invention comprises a white filler and at least one compound represented by the following formula (I) with respect to at least one rubber component selected from natural rubber and / or diene synthetic rubber. It is characterized by being blended.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]

  The rubber component used in the rubber composition of the present invention comprises natural rubber and / or diene synthetic rubber. Here, examples of the diene-based synthetic rubber include polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), butyl rubber (IIR), and ethylene-propylene copolymer. These rubber components may be used alone or in a blend of two or more.

Examples of the white filler used in the rubber composition of the present invention include silica, aluminum hydroxide, alumina, clay, calcium carbonate and the like. Among these, silica and aluminum hydroxide are preferable from the viewpoint of reinforcing properties. Is particularly preferred.
Silica that can be used is not particularly limited, and those used in commercially available rubber compositions can be used, among which wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), colloidal silica, etc. are used. In particular, the use of wet silica is preferred.

The amount of these white fillers is preferably in the range of 5 to 200 parts by weight, more preferably in the range of 5 to 150 parts by weight, even more preferably, with respect to 100 parts by weight of the rubber component. 5 to 120 parts by mass, more preferably 30 to 120 parts by mass, and still more preferably 60 to 100 parts by mass. In particular, in the case of the present invention, the effect of the present invention can be exhibited even if silica is a high blending of 60 parts by mass or more with respect to 100 parts by mass of the rubber component.
From the viewpoint of the effect of reducing the hysteresis with respect to 100 parts by mass of the rubber component, the amount of the white filler is preferably 5 parts by mass or more, and is preferably 200 parts by mass or less from the viewpoint of improving workability.

When silica is used as the white filler to be used, it is preferable to use a silane coupling agent from the viewpoint of reinforcing properties.
The silane coupling agent that can be used is not particularly limited, and examples thereof include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, and bis (3-triethoxysilylpropyl) disulfide. Bis (2-triethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltri Ethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, 3-chloropropylmethoxysilane, 3- Lolopropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N- Dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazole tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-triethoxysilyl Propyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mer At least one of ptopropyldimethoxymethylsilane, 3-nitropropyldimethoxymethylsilane, 3-chloropropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, dimethoxymethylsilylpropylbenzothiazole tetrasulfide, etc. Is mentioned.

The blending amount of these silane coupling agents varies depending on the blending amount of silica, but preferably 1 to 20 parts by weight, more preferably 6 from the viewpoint of exothermicity, with respect to 100 parts by weight of silica. A range of ˜12 parts by mass is desirable.
The blending amount of the silane coupling agent is preferably 1 part by mass or more from the viewpoint of the effect of adding the coupling agent to 100 parts by mass of silica, and from the viewpoint of maintaining reinforcement and heat generation, 20 parts by mass or less. preferable.

In the present invention, carbon black or the like can be used as a reinforcing filler in addition to the white filler.
Carbon black that can be used is not particularly limited, and grades such as FEF, SRF, HAF, ISAF, and SAF can be used.
The blending amount of these carbon blacks is also not particularly limited, but is preferably 0 to 60 parts by mass, more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the rubber component. . In addition, 60 mass parts or less are preferable from a viewpoint of maintaining exothermic property.

〔上記式（Ｉ）中において、Ｒ_１〜Ｒ_３のうち少なくとも１つが、下記式（II）で表される基を表し、残余のＲ_１〜Ｒ_３が、下記式（III）で表される基を表す。〕

〔式（II）中、Ｒ_４は、炭素数１〜２４のアルキル基又はアルケニル基を表し、該アルキル基及びアルケニル基は直鎖状、分枝鎖状及び環状の何れでもよく、また、Ａは炭素数１〜６のアルキレン基である。〕

〔式（III）中、Ｒ_５は、炭素数１〜６のアルキレン基であり、また、ｎは平均付加モル数を意味し、０〜５となる数であり、ｍは１〜３となる整数である。〕 The compound represented by the following formula (I) used in the present invention is blended to reduce the unvulcanized viscosity of the silica-blended rubber and improve the heat build-up of the vulcanized rubber to exert the effects of the present invention. is there.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]

In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the above formula (II), and the remaining R _{1 to} R ₃ are represented by the above formula (III). It is preferable that R ₁ represents a group represented by the above formula (II), and R ₂ and R ₃ represent a group represented by the above formula (III).
In the above formula (II), R ₄ is an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, isopentyl group, hexyl group, isoheptyl group, 2-ethylhexyl group, octyl group, isononyl group, decyl group, Alkyl groups such as dodecyl group, isotridecyl group, tetradecyl group, hexadecyl group, isocetyl group, octadecyl group, isostearyl group, docosyl group, tetracosyl group, allyl group, 3-butenyl group, methallyl group, 2-methyl-3-butenyl Group, 3-methyl-3-butenyl group, 1,1, -dimethyl-2-propenyl group, 4-pentenyl group Examples thereof include alkenyl groups such as oleyl group and tetracosilidene (tetracosenyl) group, preferably an alkyl group or alkenyl group having 6 to 18 carbon atoms, more preferably 11 to 18 carbon atoms. May be linear, branched or cyclic, and is a heptyl group, 2-ethylhexyl group, undecyl group, tridecyl group, pentadecyl group, heptadecyl group or heptadecenyl group.
As A of said formula (II), a C1-C6 alkylene group is mentioned, A methylene group, ethylene group, and a propylene group are especially preferable.

Further, in the above formula (III), R ₅ may be an alkylene group having 1 to 6 carbon atoms, preferably an ethylene group or a propylene group, and n means an average number of added moles. N is preferably a number from 0 to 3, more preferably 0. The n R _{5 s} may be the same or different.
Moreover, m is an integer of 1-3, 1-2 are preferable and 1 is still more preferable. Specifically, they are a methyl group, an ethyl group, a propyl group, and an isopropyl group.

Specific examples of the compound represented by the formula (I) that can be used include N-lauroylaminopropyl-N, N-dimethylamine, N-lauroylaminoethyl-N, N-diethylamine, and N-lauroyl. Aminopropyl-N, N-diethylamine, N-palmitoylaminopropyl-N, N-dimethylamine, N-palmitoylaminoethyl-N, N-diethylamine, N-stearoylaminopropyl-N, N-dimethylamine, N-stearoyl Examples include at least one of aminoethyl-N, N-diethylamine, di (N-lauroylaminoethyl) -N-methylamine, and tri (N-lauroylaminoethyl) amine. Among them, N-lauroylaminopropyl- N, N-dimethylamine, N-lauroylaminoethyl -N, N-diethylamine, N-palmitoylaminopropyl-N, N-dimethylamine, N-palmitoylaminoethyl-N, N-diethylamine, N-stearoylaminopropyl-N, N-dimethylamine, and N-stearoylamino It is desirable to use one or more selected from ethyl-N, N-diethylamine.
In addition, the synthesis | combining method of the amide amine which is a compound represented by the said formula (I) is known, can be obtained by various manufacturing methods, and may use a commercially available thing.

The compounding amount of at least one of these compounds is preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the rubber component, more preferably 1.0 from the viewpoint of exerting further effects of the present invention. -15 mass parts is preferable, 1.5-10 mass parts is more preferable, and 2-8 mass parts is still more preferable. Moreover, 0.5-20 mass parts is preferable with respect to 100 mass parts of silica, as for the compounding quantity of this amidoamine, 1-15 mass parts is more preferable, 2-12 mass parts is still more preferable, 3-10 Part by mass is even more preferable.
When the compounding amount of at least one kind of the compound is 0.5 parts by mass or more with respect to 100 parts by mass of the rubber component, the effect of reducing the unvulcanized viscosity is high. Small and preferable.

In the rubber composition of the present invention, in addition to the rubber component, the white filler, and the compound represented by the formula (I), a compounding agent usually used in the rubber industry, such as an anti-aging agent and a softening agent. , Stearic acid, zinc white, vulcanization accelerator, vulcanization acceleration aid, vulcanizing agent, and the like can be appropriately selected and blended within a range not impairing the object of the present invention. As these compounding agents, commercially available products can be suitably used.
The rubber composition of the present invention comprises a rubber component, silica, at least one compound represented by the above formula (I), and various compounding agents appropriately selected as necessary, such as a roll, an internal mixer, etc. Tires of pneumatic tires such as tire treads, under treads, carcass, sidewalls, bead parts, etc., obtained by kneading using a kneading machine, heating, extruding, etc. It can be used for applications such as anti-vibration rubber, belts, hoses, and other industrial products as well as the use of members.

The reason why the rubber composition thus configured improves the dispersibility of the white filler, particularly silica, in the rubber composition, improves the viscosity reduction of the unvulcanized rubber, and improves the processability. Is inferred as follows.
That is, in the rubber composition of the present invention, a compound represented by the above formula (I) in a compounding system in which silica is blended with at least one rubber component selected from natural rubber and / or diene synthetic rubber. When at least one of these is blended, the silica surface is hydrophobized to suppress aggregation between silicas, reduce the viscosity of the unvulcanized rubber, and to suppress the adsorption of the accelerator on the silica surface. It is presumed that the property will also be good.

Next, the tire of the present invention is produced by a usual method using the rubber composition of the present invention. That is, if necessary, the rubber composition of the present invention in which various compounding agents are blended as described above is extruded as a tire member at a non-vulcanized stage, for example, a tread member, and then on a tire molding machine. Paste molding is performed by a normal method, and a green tire is molded. The green tire is heated and pressed in a vulcanizer to obtain a tire. The tire of the present invention thus obtained is excellent in low heat build-up, so that the fuel efficiency is good and the processability of the rubber composition is good, so that the productivity is also excellent. Become.
Furthermore, the unvulcanized viscosity reducing method of the present invention is represented by the above formula (I) in a compounding system in which silica is blended with at least one rubber component selected from natural rubber and / or diene synthetic rubber. By blending at least one of the compounds to be produced, the silica surface is hydrophobized, thereby suppressing the aggregation of the silica and reducing the viscosity of the unvulcanized rubber.

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated in more detail, this invention is not limited to the following Example at all.

<Production Examples 1-3>
As the compound to be used, those obtained by the following production methods were used.
(Production Example 1)
In a 1 liter five-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a pressure gauge, 284.5 g of stearic acid (molecular weight 284.5, 1 mol) and 71.5 g of dimethylaminopropylamine (molecular weight 102. 2, 0.7 mol), and the temperature was raised to 150 ° C. while blowing nitrogen gas at 100 cc / Hr from the capillary tube. After aging for 2 hours, the temperature was raised to 180 ° C., and 30.7 g of dimethylaminopropylamine (molecular weight 102.2, 0.3 mol) was added dropwise over 1 hour. Thereafter, the mixture was kept for 2 hours under these conditions, and after confirming that the acid value (AV) was 10 or less, the mixture was cooled to 50 ° C. to obtain 355 g of N-stearoylaminopropyl-N, N-dimethylamine. It was.

(Production Example 2)
In Production Example 1, dimethylaminopropylamine was changed to diethylaminoethylamine (molecular weight 116.2), the initial charge was 81.3 g (0.7 mol), and after aging and temperature increase, the charge was 34.9 g (0.3 mol). Except for the above, it was carried out in the same manner as in Production Example 1 to obtain 363 g of N-stearoylaminoethyl-N, N-diethylamine.

(Production Example 3)
In Production Example 1, stearic acid was changed to 400 g of lauric acid (molecular weight 200, 2 mol), dimethylaminopropylamine was changed to di (2-aminoethyl) methylamine (molecular weight 117.2), and the initial charge was 82. Di (N-lauroylaminoethyl) -N-methylamine was prepared in the same manner as in Production Example 1 except that 0 g (0.7 mol) and the amount after aging and temperature increase were changed to 35.2 g (0.3 mol). 451 g was obtained.

[Examples 1-3 and Comparative Examples 1-2]
A rubber composition was prepared by a conventional method with the formulation shown in Table 1 below. The numerical value in a table | surface is a mass part.
About each obtained rubber composition, the unvulcanized rubber viscosity was measured with the following measuring method. Further, the obtained rubber composition was vulcanized at 160 ° C. for 14 minutes. The obtained vulcanized rubber was measured for viscoelasticity (tan δ) by the following measurement method.
These results are shown in Table 1 below.

[Measurement method of unvulcanized rubber viscosity]
The unvulcanized rubber viscosity was measured in accordance with JIS K 6300-1: 2001 (Mooney viscosity).
The evaluation was expressed as an index with the value of Comparative Example 1 being 100. The smaller the value of the unvulcanized rubber viscosity, the better the workability.

[Measurement method of viscoelasticity (tan δ)]
Using a viscoelasticity measuring device (manufactured by Rheometrics), tan δ was measured at a temperature of 50 ° C., a strain of 5%, and a frequency of 15 Hz. The smaller this value, the lower the heat buildup and the better the fuel economy.

* 1 to * 14 in Table 1 are as follows.
* 1) Toughden 2830 (manufactured by Asahi Kasei Chemicals) (100 parts by mass of rubber component, 37.5 parts by mass of oil component)
* 2) Seast 7HM [Tokai Carbon Co., Ltd.]
* 3) “Nipseal VN3” manufactured by Tosoh Silica Corporation
* 4) Bis (3-triethoxysilylpropyl) tetrasulfide * 5) Microcrystalline wax, Ozoace 0701 (manufactured by Nippon Seiwa Co., Ltd.)
* 6) Nocrack 6C (Ouchi Shinsei Chemical Co., Ltd.)
* 7) Non-flex RD-S [Seiko Chemical Co., Ltd.]
* 8) Noxeller D [Ouchi Shinsei Chemical Co., Ltd.]
* 9) Noxeller DM (Ouchi Shinsei Chemical Co., Ltd.)
* 10) Sunseller CM-G [manufactured by Sanshin Chemical Industry Co., Ltd.]
* 11) Farmin DM8098 (Dimethylstearylamine, manufactured by Kao Corporation)
* 12) Production Example 1 [N-stearoylaminopropyl-N, N-dimethylamine]
* 13) Production Example 2 [N-stearoylaminoethyl-N, N-diethylamine]
* 14) Production Example 3 [Di (N-lauroylaminoethyl) -N-methylamine]

  As is clear from Table 1 above, the rubber compositions of Examples 1 to 3 within the scope of the present invention were compared with Comparative Examples 1 and 2 that were outside the scope of the present invention. From the evaluation result of tan δ), it has been found that the rubber composition has an effect of reducing the viscosity of the unvulcanized rubber and has low heat build-up and good fuel efficiency.

  It can be suitably used for rubber products such as anti-vibration rubbers, belts, hoses, etc., as well as applications for tire members of pneumatic tires such as tire treads, under treads, carcass, sidewalls, and bead portions.

Claims (6)

It is characterized in that at least one rubber component selected from natural rubber and / or diene-based synthetic rubber is blended with a white filler and at least one compound represented by the following formula (I). Rubber composition.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]   5 to 200 parts by mass of a white filler and 0.5 to 15 parts by mass of at least one compound represented by the above formula (I) are blended with 100 parts by mass of the rubber component. Item 2. The rubber composition according to Item 1. The compound represented by the general formula (1) is N-lauroylaminopropyl-N, N-dimethylamine, N-lauroylaminoethyl-N, N-diethylamine, N-palmitoylaminopropyl-N, N-dimethylamine. 1 or more selected from the group consisting of N-palmitoylaminoethyl-N, N-diethylamine, N-stearoylaminopropyl-N, N-dimethylamine, and N-stearoylaminoethyl-N, N-diethylamine Item 3. The rubber composition according to Item 1 or 2.   Furthermore, a silane coupling agent is mix | blended, The rubber composition as described in any one of Claims 1-3 characterized by the above-mentioned.   A tire comprising the rubber composition according to any one of claims 1 to 4 as a tire member. An unvulcanized rubber comprising a white filler and at least one compound represented by the following formula (I) in combination with at least one rubber component selected from natural rubber and / or diene synthetic rubber Viscosity reduction method.

[In the above formula (I), at least one of R _{1 to} R ₃ represents a group represented by the following formula (II), and the remaining R _{1 to} R ₃ are represented by the following formula (III). Represents a group. ]

[In the formula (II), R ₄ represents an alkyl group or alkenyl group having 1 to 24 carbon atoms, and the alkyl group and alkenyl group may be any of linear, branched, and cyclic. Is an alkylene group having 1 to 6 carbon atoms. ]

Wherein (III), _{R 5} is an alkylene group having 1 to 6 carbon atoms, also, n represents mean average addition mole number is the number to be 0 to 5, m is 1 to 3 It is an integer. ]