JP2013249450A - Surface-coating agent for unvulcanized tire, and method of producing tire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-coating agent for unvulcanized tires capable of maintaining good appearance of a tire by simply making inconspicuous a coloring component due to an antiaging agent, especially an amine-based antiaging agent, and/or a wax, without mixing a rubber composition for tire sidewall or tread with a surfactant.SOLUTION: A surface-coating agent for unvulcanized tires contains 5-100 mass% of a surfactant. A method of producing a tire includes: a step of coating the surface-coating agent onto a tread part of the unvulcanized tire, and at least a part of the outer main surface of a sidewall part; and a step of vulcanizing the coated unvulcanized tire.

Description

  The present invention relates to a surface coating agent for an unvulcanized tire that can improve browning and whitening of tire outer rubber, and a method for producing a tire using the same.

  In general, a rubber article made from natural rubber or a diene synthetic rubber is deteriorated in the presence of ozone, and a crack occurs on the surface. This crack progresses due to static and dynamic stress applied to the rubber article, and as a result, the rubber article is broken.

  In order to suppress the occurrence and progress of cracks due to ozone, the rubber article has an anti-aging agent such as N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine as an anti-aging agent. A rubber composition containing an agent is applied. The rubber composition contains a wax for forming a protective film on the surface of the rubber article for the purpose of static protection from ozone.

  However, although the amine-based anti-aging agent and the wax are effective in suppressing the generation and progress of cracks in the presence of ozone, they are easy to move through a polymer substrate such as a rubber component, and in a short period, particularly rubber articles, It shifts to the surface of the tire and deteriorates the appearance by changing the color of the rubber article during storage and use. Here, when the amine-based anti-aging agent moves to the surface, the surface turns brown, and when the wax moves to the surface, the surface turns white.

In contrast, a rubber composition for a tire sidewall is disclosed a technique for preventing discoloration due to an amine anti-aging agent and wax by blending a polyoxyethylene ether type nonionic surfactant or a sorbitan type surfactant. (See Patent Documents 1 to 4).
However, physical properties such as scorch properties may change when a surfactant is incorporated into the compounded rubber. In addition, since it is not economical to prepare a huge variety of tire rubber compositions, it is difficult to change the type and amount of the surfactant in accordance with the type and size of the tire.
Further, in order to improve the mold releasability of the mold after vulcanization of the tire, an outer surface liquid containing a release agent such as silicone oil is usually applied to the outer surface of the unvulcanized tire and then vulcanized. To be done. However, the outer surface liquid considers mold releasability and has no viewpoint of preventing discoloration of the tire, so there was no viewpoint of blending a predetermined amount of surfactant.

JP-A-5-194790 JP 2000-63566 A JP 2004-307812 A JP 2006-83264 A

  Accordingly, an object of the present invention is to easily color an anti-aging agent (in particular, an amine-based anti-aging agent) and / or a wax without adding a surfactant to a rubber composition for a tire sidewall or a tread. An object of the present invention is to provide a surface coating agent for an unvulcanized tire that can keep components inconspicuous and maintain a good appearance of the tire, and a method for producing a tire using the same.

  As a result of intensive studies to solve the above problems, the present inventors have applied a specific surface coating agent to at least a part of the outer surface of the tread portion and the sidewall portion of the unvulcanized tire. The present inventors have found that an anti-aging agent (particularly, an amine-based anti-aging agent) and / or a colored component due to wax can be made inconspicuous and the appearance of the tire can be kept good, and the present invention has been completed.

That is, the present invention
[1] A surface coating agent for an unvulcanized tire containing 5 to 100% by mass of a surfactant, and [2] a tread portion and a sidewall portion of the unvulcanized tire with the surface coating agent described in [1] above. It is the manufacturing method of a tire including the process of apply | coating to the at least one part outer surface of this, and the process of vulcanizing the applied unvulcanized tire.

  According to the present invention, an anti-aging agent (particularly, an amine-based anti-aging agent) and / or a coloring component by wax can be simply added without adding a surfactant to a rubber composition for tire sidewalls or treads. It is possible to provide a surface coating agent for an unvulcanized tire that can be made inconspicuous and can maintain a good appearance of the tire, and a tire manufacturing method using the same.

The present invention is described in detail below.
1st invention of this invention is the surface coating agent for unvulcanized tires containing 5-100 mass% of surfactant. If it is less than 5% by mass, the effect of preventing discoloration due to an amine anti-aging agent and wax and the effect of giving gloss to the surface are reduced.
The surfactant used in the present invention is preferably a liquid or a viscous fluid at 25 ° C. from the viewpoint of application. When the viscosity of the surfactant is low, the surface coating agent of the present invention may be 100% by mass of the surfactant, but from the viewpoint of ease of application, the amount of the surfactant may be 5 to 50% by mass. Good. As the solvent in this case, water or an outer surface liquid used in a tire manufacturing method can be used. When the amount of the surfactant is 50% by mass or less, spray coating is easily performed. Moreover, it becomes possible to mix | blend surfactant with the conventional outer surface liquid, and to use it as a surface coating agent, and it can show | play simultaneously the effect which suppresses the product defect which is the characteristics as an outer surface liquid. From these viewpoints, the surface coating agent for an unvulcanized tire of the present invention is preferably aqueous. In the present invention, the term “aqueous” means that it has a property of being easily dissolved in water.
Further, the surface coating agent of the present invention is preferably an amount of the surfactant of 9% by mass or more because the effect of preventing discoloration can be obtained satisfactorily. From this viewpoint and ease of application, the amount of the surfactant is more preferably 9 to 50% by mass.
The browning of the tire hull is caused by the amine-based anti-aging agent and the wax passing through the polymer substrate such as a rubber component to the tire surface, the wax depositing on the tire surface to form an uneven surface, and light scattering occurs. The amine-based anti-aging agent adhering to the uneven surface is oxidized and becomes a colored component, so that it looks like a brown discoloration. The surfactant of the surface coating agent of the present invention smoothes the uneven surface of the wax deposited on the surface, thereby improving the light scattering state and improving browning.

As the surfactant according to the present invention, nonionic, cationic, anionic, amphoteric surfactants and the like can be used. From the compounds represented by the following general formulas (I) to (VII) It is preferable that it is at least one selected.
R ¹ —O— (CH ₂ CH ₂ O) _m —H (I)
In the formula (I), R ¹ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group are any of linear, branched and cyclic M may represent 10-50.

式（II）において、Ｒ²は、炭素数１〜１５のアルキル基又は炭素数２〜１５のアルケニル基を表し、該アルキル基及び該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；ｎは１０〜５０を示す。

In the formula (II), R ² represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms, and the alkyl group and the alkenyl group are any of linear, branched and cyclic N may represent 10-50.

式（III）において、Ｒ³は、炭素数１〜１４のアルキル基又は炭素数２〜１４のアルケニル基を表し、該アルキル基及び該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；ｐ、ｑ及びｒはそれぞれ独立して０〜５０を示し、ｐ、ｑ及びｒの総和が０〜５０を示す。

In the formula (III), R ³ represents an alkyl group having 1 to 14 carbon atoms or an alkenyl group having 2 to 14 carbon atoms, and the alkyl group and the alkenyl group are any of linear, branched and cyclic P, q and r each independently represent 0 to 50, and the sum of p, q and r represents 0 to 50.

式（IV）において、Ｒ⁴は、炭素数１〜１４のアルキル基又は炭素数２〜１４のアルケニル基を表し、該アルキル基及び該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；ｐ、ｑ及びｒはそれぞれ独立して０〜５０を示し、ｐ、ｑ及びｒの総和が０〜５０を示す。

In the formula (IV), R ⁴ represents an alkyl group having 1 to 14 carbon atoms or an alkenyl group having 2 to 14 carbon atoms, and the alkyl group and the alkenyl group are any of linear, branched and cyclic P, q and r each independently represent 0 to 50, and the sum of p, q and r represents 0 to 50.

式（Ｖ）において、Ｒ⁵は、炭素数１〜２４のアルキル基又は炭素数２〜２４のアルケニル基を表し、該アルキル基及び該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；ｓ及びｔはそれぞれ独立して０〜３０を示し、ｓ及びｔの双方が０であってもよい。

In the formula (V), R ⁵ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group are any of linear, branched and cyclic S and t each independently represent 0 to 30, and both s and t may be 0.

式（VI）において、Ｒ¹¹〜Ｒ¹⁶は、それぞれ独立して、炭素数１〜２４のアルコキシカルボニル基、炭素数１〜２４のアルキル基及び炭素数２〜２４のアルケニル基から選ばれる置換基、又は水素原子を表し、該置換基は直鎖状、分枝鎖状及び環状の何れでもよく、Ｒ¹¹〜Ｒ¹⁶は同一でも異なってもよい；ａ、ｂ、ｃ、ｄ、ｅ及びｆはそれぞれ独立して０〜６０を示す。

In the formula (VI), R ^{11 to} R ¹⁶ are each independently a substituent selected from an alkoxycarbonyl group having 1 to 24 carbon atoms, an alkyl group having 1 to 24 carbon atoms, and an alkenyl group having 2 to 24 carbon atoms. Or a hydrogen atom, and the substituent may be linear, branched or cyclic, and R ^{11 to} R ¹⁶ may be the same or different; a, b, c, d, e and f Each independently represents 0-60.

式（VII）において、Ｒ²⁰は炭素数１〜２４のアルキル基又は炭素数２〜２４のアルケニル基を表し、該アルキル基及び該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；Ｍ⁺はアルカリ金属カチオン又は｛ＮＨ_x（ＣＨ₂ＣＨ₂ＯＨ）_4-X｝⁺ を表し、
ｘは１又は２の整数を示し；ｕは１〜５０を示す。
式（VII）において、硫酸塩を形成する対イオンであるＭ⁺として、ナトリウム塩及びトリエタノールアミン塩が挙げられる。

In the formula (VII), R ²⁰ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group may be linear, branched or cyclic. well; M ⁺ is an alkali metal cation or _{{NH x (CH 2 CH 2} OH) 4-X} represents ^+,
x represents an integer of 1 or 2; u represents 1 to 50.
In the formula (VII), examples of M ⁺ which is a counter ion forming a sulfate include sodium salt and triethanolamine salt.

The compounds represented by the above general formulas (I) to (VII) used for the surface coating agent of the present invention may be used alone as a surfactant or in combination of two or more. Good.
The compounds represented by the above general formulas (I) to (VI) are nonionic surfactants, and the HLB value representing hydrophilicity to hydrophobicity is preferably 6 to 20, and 9 from the viewpoint of solubility. ~ 20 is preferred.
Here, the HLB value is defined by the Griffin method (HLB value = 20 × total molecular weight of hydrophilic portion / molecular weight of surfactant) for ether surfactants. The ester surfactant is defined by the Atlas method [Saponification value is S, Acid value of fatty acid constituting the surfactant is A, and HLB value is 20 (1-S / A)].

As the nonionic surfactant represented by the above general formulas (I) to (VI) and the anionic surfactant represented by the above general formula (VII) used for the surface coating agent of the present invention, A commercial item can be used conveniently.
For example, as the nonionic surfactant represented by the above general formula (I), a polyoxyethylene alkyl ether type nonionic surfactant manufactured by Kao Corporation, trade name “Emulgen” (registered trademark) series is available. Preferably mentioned.
As the nonionic surfactant represented by the general formula (II), a polyoxyethylene fatty acid ester type nonionic surfactant manufactured by Kao Corporation, trade name “Emanon” (registered trademark) series is preferable. Can be mentioned.
Examples of the nonionic surfactants represented by the above general formulas (III) and (IV) include polyoxyethylene sorbitan fatty acid ester type nonionic surfactants manufactured by Kao Corporation, trade name “Leodol” (registered trademark) ) Series is preferred.
Examples of the nonionic surfactant represented by the general formula (V) include polyoxyethylene alkylamine type nonionic surfactants manufactured by Kao Corporation, trade name “AMIET” (registered trademark) series, NOF A polyoxyethylene alkylamine type nonionic surfactant manufactured by Co., Ltd., trade name “Naymin” (registered trademark) series is preferably mentioned.
Preferable examples of the nonionic surfactant represented by the general formula (VI) include tetraoleic acid polyoxyethylene sorbite manufactured by NOF Corporation, trade name “UNIOX ST-30E” (registered trademark). It is done.
Moreover, as anionic surfactant represented by the said general formula (VII), the polyoxyethylene alkyl sulfate ester salt made from NOF Corporation, brand name "Persoft" (trademark) series is mentioned suitably. .

  Next, the second invention of the present invention will be described. The second invention includes a step of applying the surface coating agent of the present invention to at least a part of the outer surface of the tread portion and the sidewall portion of the unvulcanized tire, and vulcanizing the coated unvulcanized tire. The manufacturing method of the tire including the process to do. Examples of the application method include spray application using a spray gun or the like, and brush application. The application to the unvulcanized tire may be carried out by a single application as a surface coating agent having a function as an outer surface liquid by previously mixing a surfactant in the outer surface liquid, You may apply | coat a surface coating agent and an outer surface liquid separately. The step of vulcanizing the coated unvulcanized tire may be vulcanized by a normal method.

The rubber composition of at least one of the tread portion and the sidewall portion of the tire includes at least one selected from an amine-based anti-aging agent, paraffin wax, and microcrystalline wax in order to suppress generation and progress of cracks due to ozone. It is preferable to include. The production method of the second aspect of the invention keeps the tire appearance good by making the browning caused by the anti-aging agent of the rubber composition and / or whitening caused by wax such as paraffin wax and microcrystalline wax inconspicuous. be able to.
Examples of the amine anti-aging agent include N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine (6PPD), N-isopropyl-N′-phenyl-p-phenylenediamine (IPPD). ), N, N′-diphenyl-p-phenylenediamine (DPPD), and the like.
Examples of the paraffin wax include those manufactured by Nippon Seiwa Wax Co., Ltd. and Nippon Oil Refinery Co., Ltd. As the microcrystalline wax, a product name “Ozoace” series manufactured by Nippon Seiwa Co., Ltd., a product name “Santite” series manufactured by Seiko Chemical Co., Ltd. and the like can be suitably used.

In the rubber composition of at least one of the tread portion and the sidewall portion of the tire obtained by the production method of the present invention, a rubber component such as natural rubber, diene-based synthetic rubber, and non-diene-based rubber is not selected. The rubber composition further includes carbon black / silica fillers, vulcanizing agents, vulcanization accelerators, scorch inhibitors, softeners, zinc oxide, stearic acid, silane coupling agents, etc. The compounding agent used can be appropriately selected and blended within a range that does not impair the object of the present invention. As these compounding agents, commercially available products can be suitably used.
In addition, the said rubber composition can be manufactured by knead | mixing a rubber component and the various compounding agents suitably selected as needed, heat-injecting, extrusion, etc.
Moreover, carbon black and silica can be contained as a reinforcing filler. Carbon black is not particularly limited, and any commercially available silica can be used. Among them, wet silica, dry silica, and colloidal silica can be used. It is preferable to use, and it is particularly preferable to use wet silica. In addition, when using a silica as a reinforcing filler, it is preferable to contain about 1-20 mass% of silane coupling agents with respect to a silica from a reinforcement viewpoint.

  The tire obtained by the production method of the present invention can be used not only for passenger cars, trucks, buses, agriculture, motorcycles, construction machinery, and aircraft. Further, either a radial tire or a bias tire can be used.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.
In addition, the discoloration degree of the rubber composition was evaluated by the following method.
(1) Color change degree The color change degree of a vulcanized rubber test piece was evaluated using the color meter (The Nippon Denshoku Industries Co., Ltd. make, model name "NF333"). The measured color data was expressed as L *, a *, b *. L * value indicates brightness, and a * and b * indicate color. The a * and b * values are 0, indicating no color. The positive value of a * is red, and the negative value is green. A positive b * value is yellow for a positive value and blue for a negative value. Regarding the degree of discoloration, the degree of discoloration after being allowed to stand was evaluated based on the L value, a * value, b * value, and the degree of discoloration by visual observation after leaving the vulcanized rubber piece for one month under the environmental conditions of indoor standing in summer.
The degree of discoloration is evaluated on a five-point scale, where 5 is the case where discoloration is severely recognized, 4 is the case where discoloration is observed in more than half of the whole, and 3 is the case where discoloration is observed in less than half of the whole. Is 2 and 1 is the case where no discoloration is observed.

Examples 1-36 and Comparative Example 1
The rubber compositions of four kinds of compounding recipes of compounding 1 to 4 shown in Table 1 were prepared, and Examples 1 to 36 and Comparative Example 1 shown in Tables 2 and 3 were formed on the surface of these unvulcanized rubber test pieces. The 37 types of surface coating agents for unvulcanized tires were spray-coated with a spray gun and then vulcanized at 160 ° C. for 14 minutes. The discoloration degree of the obtained vulcanized rubber test piece was evaluated by the above method. The results are shown in Tables 2 and 3.

[note]
* 1 Emulsion polymerization SBR, manufactured by JSR Corporation, trade name “SBR # 1500”
* 2 Product name "JSR BR01" manufactured by JSR Corporation
* 3 Carbon Black N234, manufactured by Tokai Carbon Co., Ltd., trade name “SEAST 7HM”
* 4 Carbon Black N550, manufactured by Asahi Carbon Co., Ltd., trade name “Asahi # 65”
* 5 Product name “Nip Seal AQ” manufactured by Tosoh Silica Co., Ltd.
* 6 Bis (3-ethoxysilylpropyl) tetrasulfide, manufactured by Evonik Industries AG, trade name “Si69” (registered trademark)
* 7 Microcrystalline wax, manufactured by Nippon Seiwa Co., Ltd., trade name “Ozoace-0280”
* 8 Process oil, manufactured by Fuji Kosan Co., Ltd., trade name “Fukkor Aromax 3B”
* 9 N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine (6PPD), manufactured by Ouchi Shinsei Chemical Co., Ltd., trade name “NOCRACK 6C”
* 10 2,2,4-Trimethyl-1,2-dihydroquinoline polymer, manufactured by Seiko Chemical Co., Ltd., trade name “Nonflex RD-S”
* 11 1,3-diphenylguanidine, manufactured by Ouchi Shinsei Chemical Co., Ltd., trade name “Noxeller D”
* 12 Di-2-benzothiazolyl disulfide, manufactured by Ouchi Shinsei Chemical Co., Ltd., trade name “Noxeller DM”
* 13 N-cyclohexyl-2-benzothiazolylsulfenamide, manufactured by Sanshin Chemical Industry Co., Ltd., trade name "Sunseller CM-G"

[note]
Compound A: Nonionic surfactant manufactured by Kao Corporation, trademark “Emulgen 1118”
In the chemical formula (I), R ¹ = C ₁₁ H ₂₃ , m = 18, HLB = 16.4
Compound B: Nonionic surfactant manufactured by Kao Corporation, trademark “Emulgen 408”
In the chemical formula (I), R ¹ = C ₁₈ H ₃₅ , m = 8, HLB = 10.0
Compound C: Nonionic surfactant manufactured by Kao Corporation, trademark “Emanon 1112”
In the chemical formula (II), R ² = C ₁₁ H ₂₃ , n = 12, HLB = 13.7
Compound D: Nonionic surfactant manufactured by Kao Corporation, trademark “Leodol TW-L120”
A mixture of chemical formulas (III) and (IV), R ³ = R ⁴ = C ₁₁ H ₂₃ ,
p + q + r = 20, HLB = 16.7
Compound E: Nonionic surfactant manufactured by Kao Corporation, trademark “Leodol TW-S106”
A mixture of chemical formulas (III) and (IV), R ³ = R ⁴ = C ₁₇ H ₃₅ ,
p + q + r = 6, HLB = 9.6
Compound F: Nonionic surfactant manufactured by NOF Corporation, trademark “Nymeen 207”
In the chemical formula (V), R ⁵ = C ₁₂ H ₂₅ , s + t = 7,
Compound G: Nonionic surfactant manufactured by NOF Corporation, trademark “Uniox ST-30E”
In the chemical formula (VI), R ^{11 to} R ¹⁴ = C ₁₇ H ₃₃ , R ¹⁵ = R ¹⁶ = H,
a + b + c + d + e + f = 30
Compound H: An ionic surfactant manufactured by NOF Corporation, “Persoft EP”
In the chemical formula (VII), R ²⁰ = C ₁₂ H ₂₅ , M = Na
Compound J: An ionic surfactant manufactured by NOF Corporation, “Persoft EF-T”
In the chemical formula (VII), R ²⁰ = C ₁₂ H ₂₅ or C ₁₄ H ₂₉ ,
_{^{M = N + H (CH 2}} CH 2 OH) 3

  As is apparent from Tables 2 and 3, the surface coating agents for unvulcanized tires of Examples 1 to 36 are all compared with the water of Comparative Example 1 in appearance after a one month outdoor standing test. Was good.

  Next, an unvulcanized tire of a radial tire for a passenger car having a tire size of 205 / 65R15 in which rubber compositions having four kinds of blending formulations 1 to 4 shown in Table 1 are arranged in a tire tread portion was prepared by a conventional method. (10 tires of Formulations 1, 3 and 4 respectively, 37 tires of Formulation 2) 37 kinds of unvulcanized Examples 1 to 36 and Comparative Example 1 shown in Tables 2 and 3 were applied to these tires. The tire surface coating agent was spray-coated with a spray gun and then vulcanized by a conventional method to prepare 64 radial tires for passenger cars having a tire size of 205 / 65R15. Also in this case, when the same discoloration test as described above was performed, the same evaluation result as the evaluation result of the discoloration degree of the vulcanized rubber test piece was obtained. That is, the surface coating agents for unvulcanized tires of Examples 1 to 36 all had a good appearance after a one-month outdoor standing test as compared with the water of Comparative Example 1.

  The surface coating agent for an unvulcanized tire according to the present invention and the method for producing a tire using the same, the amine anti-aging agent and the wax are transferred to the tire surface and discolored in the tire skin, particularly in the tread portion and the sidewall portion. Therefore, the appearance of the tire tread portion is improved over a long period of time. Therefore, the tire obtained by the production method of the present invention is suitably used as various pneumatic tires for passenger cars, light passenger cars, light trucks, small trucks, trucks and buses, construction vehicles and the like.

Claims (6)

  A surface coating agent for an unvulcanized tire containing 5 to 100% by mass of a surfactant. The surface coating agent for unvulcanized tires according to claim 1, wherein the surfactant is at least one selected from compounds represented by the following general formulas (I) to (VII).
R ¹ —O— (CH ₂ CH ₂ O) _m —H (I)
[In the formula (I), R ¹ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group are linear, branched and cyclic. Any may be sufficient; m shows 10-50. ]

[In the formula (II), R ² represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms, and the alkyl group and the alkenyl group are linear, branched and cyclic. Any may be sufficient; n shows 10-50. ]

[In Formula (III), R ³ represents an alkyl group having 1 to 14 carbon atoms or an alkenyl group having 2 to 14 carbon atoms, and the alkyl group and the alkenyl group are linear, branched, and cyclic. P, q and r each independently represent 0 to 50, and the sum of p, q and r represents 0 to 50. ]

[In the formula (IV), R ⁴ represents an alkyl group having 1 to 14 carbon atoms or an alkenyl group having 2 to 14 carbon atoms, and the alkyl group and the alkenyl group are linear, branched and cyclic. P, q and r each independently represent 0 to 50, and the sum of p, q and r represents 0 to 50. ]

[In Formula (V), R ⁵ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group are linear, branched, and cyclic. S and t each independently represent 0 to 30, and both s and t may be 0. ]

[In the formula (VI), R ^{11 to} R ¹⁶ are each independently a substituent selected from an alkoxycarbonyl group having 1 to 24 carbon atoms, an alkyl group having 1 to 24 carbon atoms, and an alkenyl group having 2 to 24 carbon atoms. Represents a group or a hydrogen atom, and the substituent may be linear, branched or cyclic, and R ^{11 to} R ¹⁶ may be the same or different; a, b, c, d, e and f shows 0-60 each independently. ]

[In the formula (VII), R ²⁰ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 2 to 24 carbon atoms, and the alkyl group and the alkenyl group may be linear, branched or cyclic. But well; M ⁺ an alkali metal cation or _{{NH x (CH 2 CH 2} OH) 4-X} represents ^+,
x represents an integer of 1 or 2; u represents 1 to 50. ]   The surface coating agent for an unvulcanized tire according to claim 1 or 2, wherein the surfactant is a liquid or a viscous fluid at 25 ° C.   It is aqueous, The surface coating agent for unvulcanized tires in any one of Claims 1-3.   A step of applying the surface coating agent according to any one of claims 1 to 4 to at least a part of an outer surface of a tread portion and a sidewall portion of an unvulcanized tire, and a coated unvulcanized tire And a vulcanizing step.   The tire manufacturing method according to claim 5, wherein the rubber composition of at least one of the tread portion and the sidewall portion of the tire includes at least one selected from an amine-based antioxidant, paraffin wax, and microcrystalline wax.