Emulsion composition and manufacturing method

Abstract

A method for manufacturing an emulsion composition that is simpler to produce than conventional methods and exhibits excellent emulsion stability is provided. The emulsion composition contains: a liquid conjugated diene rubber, a diluent with a vapor pressure of less than 10 Pa at 20°C, a surfactant, and water.

Description

[Technical Field]

[0001] This invention relates to an emulsion composition with excellent emulsion stability and a method for manufacturing the same. [Previous Technology]

[0002] Liquid rubber is used in various applications as a tackifier, adhesive, cold-resistance modifier for rubber, processing oil, and reactive plasticizer. In these applications, liquid rubber is generally used directly as is, but there are also cases where it is emulsified before use. When the molecular weight of liquid rubber is around several thousand, its viscosity is low, so it can be easily emulsified using common emulsifiers. However, when the molecular weight of liquid rubber is around tens of thousands, the viscosity becomes high, making emulsification difficult. In this case, although emulsification can be achieved by applying extremely high mechanical shear forces, this requires specialized equipment or complicates the manufacturing process. Furthermore, even when emulsified, the lack of stability can lead to phase separation during storage.

[0003] As a method for solving such problems, Patent Document 1 proposes a method for preparing an oil-in-water emulsion by mixing an organic solvent solution (A) of a polymer with an aqueous medium (B) in the presence of an emulsifier. The method involves mixing (A) and (B) at a specific volume ratio with low-speed stirring to prepare an oil-in-water emulsion, followed by further high-speed stirring to induce phase inversion and obtain an oil-in-water emulsion. Patent Document 2 proposes an emulsification method characterized in that, during the emulsification of liquid cis-1,4-polyisoprene rubber with a molecular weight of 10,000 to 60,000, the cis-1,4-polyisoprene rubber is not dissolved in the organic solvent, and for 100 parts by mass of the liquid cis-1,4-polyisoprene rubber, the amount of water used is at most 80 parts by mass or less. Furthermore, Patent Document 3 proposes an emulsification method using dialkyl sulfosuccinate as an emulsifier for liquid polyisoprene with a molecular weight of 10,000 to 60,000. Patent Document 4 proposes a method for manufacturing an emulsion using polyoxyethylene alkyl (allyl) ether phosphate as an emulsifier when emulsifying liquid polyisoprene with a molecular weight of 10,000 to 60,000. Moreover, Non-Patent Document 1 describes an emulsification method for liquid rubber that involves diluting with an organic solvent, mixing with an emulsifier and water, and then distilling off the organic solvent to achieve emulsification. [Prior Art Documents] [Patent Documents]

[0004] Patent Document 1: Japanese Patent Publication No. 49-332; Patent Document 2: Japanese Patent Application Publication No. 54-124043; Patent Document 3: Japanese Patent Application Publication No. 62-141033; Patent Document 4: Japanese Patent Application Publication No. 54-124040 [Non-Patent Document]

[0005] Non-patent literature 1: Journal of the Japan Rubber Association, Vol. 57, No. 10, pp. 78-89 [Summary of the Invention]

[0006] [The problem the invention aims to solve]

[0007] Although conventional methods can produce emulsion compositions, the stability of the emulsion is insufficient. Furthermore, especially in the method of Patent Document 1, specialized equipment is required because the high-viscosity composition must be stirred at high speed, making it difficult to manufacture easily. Also, in Non-Patent Document 1, the use of organic solvents necessitates a solvent distillation step, making the manufacturing method complex.

[0008] The objective of this invention is to address the aforementioned problems by providing an emulsion composition that is simpler to manufacture than conventional methods and has excellent emulsion stability, as well as a method for manufacturing the same. [Means for solving the problems]

[0009] The inventors of this case conducted various studies on the emulsification of liquid conjugated diene rubber and found that if a diluent with a vapor pressure of less than 10 Pa at 20°C is used, a very stable emulsion composition that is not prone to phase separation can be obtained. Furthermore, it was found that an emulsion composition can be obtained in a simpler way than conventional methods, thereby completing the present invention.

[0010] That is, the present invention provides the following [1] to [7]. [1] An emulsion composition comprising: a liquid conjugated diene rubber, a diluent having a vapor pressure of less than 10 Pa at 20°C, a surfactant, and water. [2] The emulsion composition as described in [1] above, wherein the liquid conjugated diene rubber comprises one or more monomer units derived from butadiene, isoprene, and β-chlorophyllin. [3] The emulsion composition as described in [1] or [2] above, wherein the liquid conjugated diene rubber is a modified conjugated diene rubber having hydrogen-bonded functional groups in a portion of the conjugated diene rubber. [4] As described in [3] above, the hydrogen-bonding functional group is selected from one or more of the following: hydroxyl, epoxy, aldehyde, acetal of aldehyde, carboxyl, salt of carboxyl, ester of carboxyl, acid anhydride of carboxyl, boronyl, salt of boronyl, ester of boronyl, silyl, and ester of silyl. [5] As described in any one of [1] to [4] above, the surfactant is a nonionic surfactant. [6] As described in any one of [1] to [5] above, the content of the surfactant in the emulsion composition is 1 to 15 parts by mass relative to a total of 100 parts by mass of the liquid conjugated diene rubber and the diluent. [7] A method for manufacturing an emulsion composition, which is a method for manufacturing an emulsion composition as described in any one of [1] to [6] above, characterized in that after mixing the liquid conjugated diene rubber, the diluent, the surfactant, and water to manufacture an oil-in-water emulsion, the diluent is not removed. [Effects of the Invention]

[0011] According to the present invention, an emulsion composition that can be manufactured more simply than conventional methods and has excellent emulsion stability, and a method thereof, can be provided.

Implementation Method

[0013] [Form for implementing the invention]

[0014] [Emulsion Composition] The emulsion composition of the present invention comprises a liquid conjugated diene rubber, a diluent with a vapor pressure of 10 Pa or less at 20°C, a surfactant, and water. According to the present invention, since the liquid conjugated diene rubber is used in combination with a diluent with a vapor pressure of 10 Pa or less at 20°C, an emulsion composition with excellent stability and low phase separation can be obtained. If the vapor pressure of the diluent at 20°C exceeds 10 Pa, the diluent may evaporate during storage, and the emulsion particles may disintegrate. In contrast, if the vapor pressure of the diluent at 20°C is less than 10 Pa, the disintegration of the emulsion particles can be suppressed. Furthermore, the emulsion composition of the present invention is easy to manufacture and has excellent processability because its viscosity does not easily increase during manufacturing. In addition, while suppressing contamination of manufacturing equipment, it has excellent manufacturing efficiency compared to manufacturing methods that use organic solvents for dilution because it eliminates the diluent removal step. Furthermore, the emulsion composition of the present invention is stable, and when used as an adhesive, it can adhere to the object being bonded more evenly and efficiently, resulting in improved adhesion.

[0015] Hereinafter, the present invention will be described in detail. <Liquid Conjugated Diene Rubber> The liquid conjugated diene rubber used in the present invention contains at least one monomer unit (hereinafter also referred to as "conjugated diene unit") derived from a conjugated diene within its molecule. For example, it is preferred that at least 50 moles of monomer units derived from a conjugated diene are contained in all monomer units of the conjugated diene rubber. In this specification, liquid conjugated diene rubber refers to a melt viscosity of 30 Pa·s or more and 4,000 Pa·s or less, measured at 38°C. From the viewpoint of improving adhesion, this melt viscosity is preferably 35 Pa·s or more, and more preferably 40 Pa·s or more. Furthermore, from the viewpoint of improving emulsion stability and processability, the melt viscosity is preferably 2,500 Pa·s or less, more preferably 1,500 Pa·s or less, even more preferably 1,000 Pa·s or less, and still more preferably 500 Pa·s or less. If the aforementioned melt viscosity is within the aforementioned range, the processability is improved because the dispersibility of the emulsion components is enhanced while simultaneously suppressing the increase in viscosity. Here, the melt viscosity of the liquid conjugated diene rubber refers to the viscosity measured using a Brookfield viscometer (Type B viscometer) at 38°C.

[0016] Examples of conjugated diene monomers include, for example, butadiene, 2-methyl-1,3-butadiene (hereinafter also called "isoprene"), 2,3-dimethylbutadiene, 2-phenylbutadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-octadiene, 1,3-cyclohexadiene, 2-methyl-1,3-octadiene, 1,3,7-octtriene, β-chlorophenene (hereinafter also called "chlorophenene"), laurylene, and chloroprene. These conjugated dienes can be used individually or in combination of two or more. From the viewpoint of adhesion when the liquid conjugated diene rubber is used as an adhesive, it is preferable that it contains one or more monomer units derived from butadiene, isoprene, and chlorophenene.

[0017] The liquid conjugated diene rubber used in this invention may also contain units derived from monomers other than the aforementioned conjugated diene monomers, to the extent that it does not impair the effects of this invention. Examples of other monomers include copolymerizable vinyl unsaturated monomers and aromatic vinyl compounds. Examples of the aforementioned vinyl unsaturated monomers include olefins such as ethylene, 1-butene, and isobutene. Examples of the aforementioned aromatic vinyl compounds include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-tributylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 2-ethyl-4-benzylmethylstyrene, 4-(phenylbutyl)styrene, 1-vinylnaphthalene, 2-vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, monochlorostyrene, dichlorostyrene, and divinylbenzene. These can be used individually or in combination of two or more. In the case where the liquid conjugated diene rubber contains monomer units derived from monomers other than conjugated diene monomers, the content is preferably 30 mol% or less, more preferably 10 mol% or less, and even more preferably 5 mol% or less.

[0018] The liquid conjugated diene rubber used in this invention is preferably a modified conjugated diene rubber having hydrogen-bonded functional groups in a portion of the conjugated diene rubber, more preferably a modified conjugated diene rubber containing conjugated diene units in at least a portion of the polymer chain and having hydrogen-bonded functional groups on the side chains or ends of the polymer chain. If the conjugated diene rubber is the aforementioned modified conjugated diene rubber, then when the emulsion composition of this invention is used as an adhesive, the modified conjugated diene rubber can improve the adhesion through its interaction with the adherend.

[0019] In this specification, "hydrogen bond" means the bonding interaction formed between a hydrogen atom (subject) bonded to a highly electronegative atom (O, N, S, etc.) and polarized as a positively charged atom, and a negatively charged atom (acceptor) with a lone pair of electrons.

[0020] In this invention, the "hydrogen-bonding functional group" is a functional group that can function as both a donor and acceptor in the aforementioned hydrogen bond. Specifically, examples include: hydroxyl, epoxy, ether, mercapto, carboxyl, carbonyl, aldehyde, amino, imino, imidazolium, carbamate, amide, urea, isocyanate, nitrile, borooxy, silanol, and their derivatives. As derivatives of the aldehyde group, acetals are examples. As derivatives of the carboxyl group, salts, esters, amides, and anhydrides are examples. As derivatives of the borooxy group, salts and esters are examples. As derivatives of the silanol group, esters are examples. Furthermore, as carboxyl groups, groups derived from monocarboxylic acids and groups derived from dicarboxylic acids are examples. From the perspective of improving adhesion and the ease of manufacturing liquid conjugated diene rubber, it is preferable to select one or more of the following: hydroxyl, epoxy, aldehyde, acetal of aldehyde, carboxyl, salt of carboxyl, ester of carboxyl, acid anhydride of carboxyl, borooxy, salt of borooxy, ester of borooxy, silyl, and ester of silyl; more preferably, it is preferable to select one or more of the following: hydroxyl, epoxy, carboxyl, salt of carboxyl, ester of carboxyl, acid anhydride of carboxyl, borooxy, salt of borooxy, and ester of borooxy; and even more preferably, it is preferable to select one or more of the following: carboxyl, ester of carboxyl, borooxy, and ester of borooxy.

[0021] From the viewpoint of improving adhesion when the emulsion composition is used as an adhesive, the average number of hydrogen-bonding functional groups in the modified conjugated diene rubber is preferably 0.5 or more per molecule, more preferably 2 or more, and even more preferably 3 or more. Furthermore, from the viewpoint of controlling the viscosity of the modified conjugated diene rubber within an appropriate range and improving processability, the average number of hydrogen-bonding functional groups is preferably 80 or less per molecule, more preferably 40 or less, even more preferably 20 or less, and even more preferably 10 or less.

[0022] The average number of hydrogen-bonded functional groups per molecule of modified conjugated diene rubber is calculated based on the following formula, derived from the equivalent (g / eq) of the hydrogen-bonded functional groups of the modified conjugated diene rubber and the number-average molecular weight Mn of styrene. The equivalent of the hydrogen-bonded functional groups of the modified conjugated diene rubber refers to the mass of the conjugated diene and other monomers other than the conjugated diene bonded to each hydrogen-bonded functional group, as needed. Average number of hydrogen-bonded functional groups per molecule = [(number-average molecular weight (Mn)) / (molecular weight of styrene unit) × (average molecular weight of conjugated diene and other monomer units other than the conjugated diene, as needed)] / (equivalent of hydrogen-bonded functional groups). The method for calculating the equivalent of hydrogen-bonded functional groups can be appropriately selected according to the type of hydrogen-bonded functional groups.

[0023] As a method for obtaining modified conjugated diene rubber, examples include: a method of obtaining it by adding a modified compound to the polymer product of a conjugated diene monomer (hereinafter also referred to as "manufacturing method (1)"); a method of obtaining it by oxidizing a conjugated diene polymer (hereinafter also referred to as "manufacturing method (2)"); a method of obtaining it by copolymerizing a conjugated diene monomer with a free radical polymerizable compound having a hydrogen-bonding functional group (hereinafter also referred to as "manufacturing method (3)"); and a method of adding a modified compound that can react with the polymerizable active end before adding a polymerization inhibitor to the polymer product of an unmodified conjugated diene monomer having a polymerization active end (hereinafter also referred to as "manufacturing method (4)").

[0024] [Manufacturing Method of Modified Conjugated Diene Rubber (1)] Manufacturing method (1) is a method of adding modified compounds to the polymer product of conjugated diene monomers, that is, unmodified conjugated diene rubber (hereinafter also referred to as "unmodified conjugated diene rubber"). Unmodified conjugated diene rubber can be obtained by polymerizing conjugated dienes and other monomers other than conjugated dienes as needed, such as by emulsion polymerization or solution polymerization.

[0025] As for the aforementioned solution polymerization method, known or conforming methods may be applied. For example, in the solvent, a Chigler catalyst, a metallocene catalyst, an active metal or active metal compound capable of anionic polymerization may be used to polymerize a monomer containing a specified amount of conjugated diene in the presence of a polar compound, as required. Examples of solvents include: aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane, and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, and methylcyclopentane; and aromatic hydrocarbons such as benzene, toluene, and xylene.

[0026] Examples of active metals capable of anionic polymerization include: alkali metals such as lithium, sodium, and potassium; alkaline earth metals such as beryllium, magnesium, calcium, strontium, and barium; and lanthanide rare earth metals such as lanthanum and neodymium. Among these active metals capable of anionic polymerization, alkali metals and alkaline earth metals are preferred, and alkali metals are even more preferred. As active metal compounds capable of anionic polymerization, organoalkali metal compounds are preferred. Examples of organoalkali metal compounds include: organomonal lithium compounds such as methyllithium, ethyllithium, n-butyllithium, dibutyllithium, tert-butyllithium, hexyllithium, phenyllithium, and stilbene; multifunctional organolithium compounds such as dilithiummethane, dilithiumnaphthalene, 1,4-dilithiumbutane, 1,4-dilithium-2-ethylcyclohexane, and 1,3,5-trilithiumbenzene; and sodium naphthalene and potassium naphthalene. Among these organoalkali metal compounds, organolithium compounds are preferred, and organomonal lithium compounds are even more preferred.

[0027] The amount of the aforementioned organoalkali metal compound used can be appropriately set according to the melt viscosity, molecular weight, etc. of the target unmodified conjugated diene rubber and modified conjugated diene rubber. Typically, 0.01 to 3 parts by mass are used relative to 100 parts by mass of all monomers containing the conjugated diene. The aforementioned organoalkali metal compound can also react with secondary amines such as dibutylamine, dihexylamine, and dibenzylamine to be used as an organoalkali metal amide.

[0028] In anionic polymerization, polar compounds are typically used to adjust the microstructure of the conjugated diene site without deactivating the reaction. Examples of polar compounds include: ether compounds such as dibutyl ether, tetrahydrofuran, ethylene glycol diethyl ether, and 2,2-di(2-tetrahydrofuranyl)propane; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides; and phosphine compounds. The polar compound is typically used in amounts of 0.01 to 1,000 moles relative to the organoalkali metal compound. The solution polymerization temperature is typically in the range of -80 to 150°C, preferably in the range of 0 to 100°C, and more preferably in the range of 10 to 90°C. The polymerization mode can be either batch or continuous. The polymerization reaction can be stopped by adding a polymerization inhibitor. Examples of polymerization inhibitors include: alcohols such as methanol and isopropanol. Unmodified conjugated diene rubber can be separated by injecting the obtained polymerization reaction solution into a poor solvent such as methanol to precipitate the polymerization product, or by washing and separating the polymerization reaction solution with water and then drying it. Among the aforementioned methods for manufacturing unmodified conjugated diene rubber, solution polymerization is preferred.

[0029] As for the aforementioned emulsification polymerization method, known methods or methods following known procedures may be applied. For example, a monomer containing a specified amount of conjugated diene may be emulsified and dispersed in the presence of an emulsifier, and then emulsified and polymerized using a free radical polymerization initiator. Examples of emulsifiers include long-chain fatty acid salts with 10 or more carbon atoms and rosin salts. Examples of long-chain fatty acid salts include potassium or sodium salts of fatty acids such as decanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, and stearic acid. Water is usually used as the dispersion solvent, but water-soluble organic solvents such as methanol and ethanol may also be included, provided that the stability during polymerization is not impaired. Examples of free radical polymerization initiators include persulfates such as ammonium persulfate and potassium persulfate, organic peroxides, and hydrogen peroxide. Chain transfer agents may also be used to adjust the molecular weight of the obtained unmodified conjugated diene rubber. Examples of chain transfer agents include: thiols such as tert-dodecyl mercaptan and n-dodecyl mercaptan; carbon tetrachloride, mercaptoacetic acid, diterpenes, terpinene, γ-terpinene, and α-methylstyrene dimers.

[0030] The temperature of emulsion polymerization can be appropriately set according to the type of free radical polymerization initiator used, and is usually in the range of 0 to 100°C, preferably in the range of 0 to 60°C. The polymerization mode can be either continuous polymerization or batch polymerization.

[0031] The polymerization reaction can be stopped by adding a polymerization inhibitor. Examples of polymerization inhibitors include amine compounds such as isopropyl hydroxylamine, diethyl hydroxylamine, and hydroxylamine, quinone compounds such as hydroquinone and benzoquinone, and sodium nitrite.

[0032] Anti-aging agents may be added as needed after the polymerization reaction stops. After the polymerization reaction stops, unreacted monomers are removed from the obtained latex as needed. Next, salts such as sodium chloride, calcium chloride, and potassium chloride are used as coagulants. Acids such as nitric acid and sulfuric acid are added as needed to adjust the pH of the coagulation system to the specified value. After the polymerization product is coagulated, the polymerization product is recovered by separating the dispersion solvent. After washing and dehydration, unmodified conjugated diene rubber can be obtained by drying. During coagulation, the latex may be mixed with the extended oil that has been prepared into an emulsion dispersion as needed to recover the oil-extended unmodified conjugated diene rubber.

[0033] (Modifying compound used in manufacturing method (1)) There are no particular limitations on the modifying compound used in manufacturing method (1). From the viewpoint of improving the adhesion when the emulsion composition is used as an adhesive, it is preferable to have a hydrogen-bonding functional group. As a hydrogen-bonding functional group, the same as those mentioned above can be cited. Among them, from the viewpoint of the strength of hydrogen bonding, hydroxyl, epoxy, aldehyde, acetal of aldehyde, carboxyl, salt of carboxyl, ester of carboxyl, acid anhydride of carboxyl, boronoxy, salt of boronoxy, ester of boronoxy, silyl, and ester of silyl are preferred.

[0034] Examples of the aforementioned modified compounds include: unsaturated carboxylic acids such as maleic acid, fumaric acid, citraconic acid, and itconic acid; unsaturated carboxylic anhydrides such as maleic anhydride, citraconic anhydride, 2,3-dimethylmaleic anhydride, and itconic anhydride; unsaturated carboxylic esters such as maleate ester, fumarate ester, citracate ester, and itconate ester; unsaturated carboxylic amides such as maleic acid amide, fumarate amide, citracate amide, and itconate amide; unsaturated carboxylic amides such as maleic acid amide, fumarate amide, citracate amide, and itconate amide; vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, mercaptomethylmethyldiethoxysilane, etc. Silane compounds such as mercaptomethyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 2-mercaptoethylmethoxydimethylsilane, 2-mercaptoethylethoxydimethylsilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane, 3-mercaptopropyldimethoxyethylsilane, 3-mercaptopropyldiethoxyethylsilane, 3-mercaptopropylmethoxydimethylsilane, 3-mercaptopropylethoxydimethylsilane, etc.; organoboronic esters such as triethyl borate, tripropyl borate, triisopropyl borate, and tributyl borate. These modified compounds with hydrogen-bonding functional groups can be used alone or in combination of two or more.

[0035] The amount of the aforementioned modified compound used is, relative to 100 parts by mass of unmodified conjugated diene rubber, preferably 0.1 to 100 parts by mass, more preferably 0.5 to 50 parts by mass, and even more preferably 1 to 30 parts by mass. The reaction temperature is generally preferably in the range of 0 to 200°C, more preferably in the range of 50 to 200°C. Furthermore, after grafting the aforementioned modified compound onto the unmodified conjugated diene rubber to introduce hydrogen-bonding functional groups, other modified compounds that can react with these functional groups can be further added to introduce other hydrogen-bonding functional groups into the polymer. Specifically, examples include grafting maleic anhydride onto unmodified conjugated diene rubber obtained by living anionic polymerization, followed by reacting with compounds containing hydroxyl groups such as 2-hydroxyethyl methacrylate or methanol, or water.

[0036] The amount of the modifying compound added to the modified conjugated diene rubber is preferably 0.5 to 40 parts by mass, more preferably 1 to 30 parts by mass, and even more preferably 1.5 to 20 parts by mass, relative to 100 parts by mass of unmodified conjugated diene rubber. The amount of the modifying compound added to the modified conjugated diene rubber can be calculated based on the acid value of the modifying compound, or it can be determined using various analytical instruments such as infrared spectroscopy and nuclear magnetic resonance spectroscopy.

[0037] The method for adding the aforementioned modified compound to unmodified conjugated diene rubber is not particularly limited. Examples include: adding liquid unmodified conjugated diene rubber, one or more modified compounds selected from unsaturated carboxylic acids, unsaturated carboxylic acid derivatives, organoboronic acid derivatives, and silane compounds, and further adding a free radical generating agent as needed, with or without an organic solvent, followed by heating. There are no particular limitations on the free radical generating agent used; commercially available organic peroxides, azo compounds, hydrogen peroxide, etc., can be used. Examples of organic solvents used in the aforementioned method include hydrocarbon solvents and halogenated hydrocarbon solvents. Among these organic solvents, hydrocarbon solvents such as n-butane, n-hexane, n-heptane, cyclohexane, benzene, toluene, and xylene are preferred.

[0038] Furthermore, when performing the addition-modified compound reaction using the aforementioned method, from the viewpoint of suppressing side reactions, an anti-aging agent may also be added. Such anti-aging agents can be commercially available, such as butylated hydroxytoluene (BHT) and N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (Nocrack 6C).

[0039] The amount of anti-aging agent added is preferably 0.01 to 10 parts by weight, and more preferably 0.05 to 5 parts by weight, relative to 100 parts by weight of unmodified conjugated diene rubber. If the amount of anti-aging agent added is within the aforementioned range, side reactions can be suppressed, and modified conjugated diene rubber can be obtained in good yield.

[0040] [Method for manufacturing modified conjugated diene rubber (2)] As manufacturing method (2), an example is a method of obtaining oxidized conjugated diene rubber by oxidizing a conjugated diene rubber that will become a raw material, wherein the oxidized conjugated diene rubber has a functional group or bond containing oxygen generated by the oxidation reaction within the molecule. Specifically, the functional group or bond can be hydroxyl, aldehyde, carbonyl, carboxyl, and ether bond. As a method for oxidizing the raw material conjugated diene rubber, examples include a method of heat treatment at a temperature above the oxidation temperature (hereinafter also referred to as "manufacturing method (2-1)"); a method of activating the raw material conjugated diene rubber by irradiating it with light of an absorption wavelength to react with oxygen (hereinafter also referred to as "manufacturing method (2-2)"). Among these, the method of obtaining the raw material conjugated diene rubber by heat treatment at a temperature above the oxidation temperature (manufacturing method (2-1)) is preferred.

[0041] [Manufacturing Method of Oxidized Conjugated Diene Rubber (2-1)] Manufacturing method (2-1) is a method of heat-treating raw material conjugated diene rubber at a temperature above the oxidation temperature. This heat treatment is carried out in a gaseous environment containing oxygen, preferably in an air gaseous environment. The heat treatment temperature is not particularly limited as long as it is at a temperature at which the raw material conjugated diene rubber will oxidize; from the viewpoint of increasing the oxidation reaction rate and improving productivity, it is preferably 150°C or higher, more preferably 170°C or higher, and even more preferably 190°C or higher. The heat treatment time is not particularly limited as long as it is within a range that will not deteriorate the raw material conjugated diene rubber; it is preferably 30 minutes or less, more preferably 20 minutes or less. Furthermore, the temperature required for the oxidation reaction can be lowered by adding a thermal free radical generator to the raw material conjugated diene rubber.

[0042] Examples of the aforementioned thermal free radical generators include peroxides, azo compounds, and redox initiators. From the viewpoint that the thermal free radical generator bonds with the conjugated diene rubber, and that the conjugated diene rubber undergoes an addition reaction containing oxygen, peroxides are preferred. Examples of peroxides include: tributyl hydroperoxide, cumene hydroperoxide, tributyl peracetate, tributyl perbenzoate, tributyl peroctanoate, tributyl peroxyneodecanate, tributyl perisobutyrate, lauryl peroxide, tripentyl peroxytrimethylacetate, tributyl peroxytrimethylacetate, dicumene peroxide, benzoyl peroxide, potassium persulfate, and ammonium persulfate.

[0043] Examples of the aforementioned azo compounds include: azobisisobutyronitrile (AIBN), 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-butyronitrile), 4,4'-azobis(4-valeric acid), 1,1'-azobis(cyclohexaneformitrile), 2-(tert-butylazo)-2-cyanopropane, 2,2'-azobis[2-methyl-N-(1,1)-bis(hydroxymethyl)-2] [-hydroxyethyl]propionic acid, 2,2'-azobis(2-methyl-N-hydroxyethyl)propionic acid, 2,2'-azobis(N,N'-dimethyleneisobutylamidinium) dichloride, 2,2'-azobis(N,N-dimethyleneisobutylamidinium), 2,2'-azobis(2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionic acid, 2,2'-azobis(isobutylamidinium) dihydrate, etc. The aforementioned thermal free radical generators can be used alone or in combination of two or more.

[0044] Furthermore, a redox initiator can also be used as the aforementioned thermal free radical generator. Examples of such redox initiators include: a composition of persulfate, sodium bisulfite, and ferrous sulfate; a composition of tributyl hydroperoxide, sodium bisulfite, and ferrous sulfate; and a composition of p-menthane hydroperoxide, ferrous sulfate, sodium ethylenediaminetetraacetate, and sodium formaldehyde sulfoxylate.

[0045] [Manufacturing Method of Oxidized Conjugated Diene Rubber (2-2)] Manufacturing method (2-2) is a method of activating the raw material conjugated diene rubber by irradiating it with light of an absorption wavelength, thereby causing it to react with oxygen. Manufacturing method (2-2) is carried out in a gaseous environment containing oxygen, preferably in an air gas environment. There are no particular restrictions on the wavelength of light used, as long as it is absorbed by the raw material conjugated diene rubber and causes a free radical reaction; preferably, it is ultraviolet light that the raw material conjugated diene rubber strongly absorbs. Alternatively, the amount of light required for the oxidation reaction can be reduced by adding a photoradical generator to the raw material conjugated diene rubber.

[0046] Examples of the aforementioned photoradical generators include: acetophenone, acetophenone benzil ketal, 1-hydroxycyclohexylphenyl ketone, 2,2-dimethoxy-1,2-diphenylethyl-1-one, xanthone, xanthone, benzaldehyde, xanthone, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4,4'-dimethoxydiphenyl ketone, benzoin propyl ether, benzoin dimethyl ketal, 1-(4-isopropylphenyl)-2-hydroxy-2-methylprop-1-one, 2-hydroxy-2-methyl-1-phenylprop-1-one, 9-thioxanthone, and diethyl-9-thioxanthone. Examples of photoradical generators include thioxanthone, 2-methyl-1-[4-(methylthio)phenyl]-2-linylprop-1-one, 2-benzyl-2-dimethylamino-1-(4-linylphenyl)butanone-1, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)one, 2,4,6-trimethylbenzyldiphenylphosphine oxide, and bis(2,6-dimethoxybenzyl)-2,4,4-trimethylpentylphosphine oxide. These photoradical generators can be used alone or in combination of two or more.

[0047] [Method for manufacturing modified conjugated diene rubber (3)] As a manufacturing method (3), a method of randomly copolymerizing, block copolymerizing or graft copolymerizing a conjugated diene monomer with a free radical polymerizable compound having hydrogen-bonding functional groups using known methods is provided.

[0048] (Free radical polymerizable compounds with hydrogen-bonded functional groups used in manufacturing method (3)) Free radical polymerizable compounds with hydrogen-bonded functional groups used in manufacturing method (3) are not particularly limited as long as they have both hydrogen-bonded functional groups and reactive multi-bonds within the molecule. Specifically, examples include: aldehydes with reactive multi-bonds, acetals of the aldehydes; monocarboxylic acids with reactive multi-bonds, salts of the monocarboxylic acids, esters of the monocarboxylic acids, and anhydrides of the monocarboxylic acids; dicarboxylic acids with reactive multi-bonds, salts of the dicarboxylic acids, esters of the dicarboxylic acids, and anhydrides of the dicarboxylic acids; and amine compounds with reactive multi-bonds, etc.

[0049] Among the aforementioned aldehydes with multiple bonds, examples of aldehydes possessing reactive carbon-carbon double bonds include: acrolein, methacrolein, crotonaldehyde, 3-butenal, 2-methyl-2-butenal, 2-methyl-3-butenal, 2,2-dimethyl-3-butenal, 3-methyl-2-butenal, 3-methyl-3-butenal, 2-pentenal, 2-methyl-2-pentenal, 3-pentenal, 3-methyl-4-pentenal, 4-pentenal, 4-methyl-4-pentenal, 2-hexenal, 3-hexenal, 4-hexenal, 5-hexenal, 7-octenal, 10-undecenal, 2-ethylcrotonaldehyde, 3-(dimethylamino)acrolein, myristoleic aldehyde, palmoleic aldehyde, oleic aldehyde, and elaidic aldehyde. Alkenes with carbon numbers of 3 to 30, preferably 3 to 25, include: aldehydes such as isoolenic aldehyde, gadoleic aldehyde, erucic aldehyde, nervonic aldehyde, linoleic aldehyde, citronellol, cinnamaldehyde, and vanillin; dienes with carbon numbers of 5 to 30, preferably 5 to 25, include: linolenic aldehyde, eleostearic aldehyde, etc., preferably 7 to 25, include: aldehydes such as linolenic aldehyde and eleostearic aldehyde; and esters with carbon numbers of 7 to 30, preferably 7 to 25, include: esters such as stearidonic aldehyde and arachidonic aldehyde. Aldehydes containing 9 to 30 carbon atoms, preferably 9 to 25 carbon atoms; pentaenyl aldehydes containing 11 to 30 carbon atoms, preferably 11 to 25 carbon atoms; and other unsaturated aldehydes. Where the aforementioned aldehydes contain cis-trans isomers, they include both the cis and trans isomers. These aldehydes can be used alone or in combination of two or more.

[0050] Among the aforementioned acetals of aldehydes having multiple bonds, examples of acetals of aldehydes having reactive carbon-carbon double bonds include the aforementioned acetals of aldehydes, specifically: 3-(1,3-dioxopentane-2-yl)-3-methyl-1-propene, an acetal of 2-methyl-3-butenal, and 3-(1,3-dioxopentane-2-yl)-2-methyl-1-propene, an acetal of 3-methyl-3-butenal, etc.

[0051] Among the aforementioned aldehydes having multiple bonds and their acetal compounds, examples of aldehydes having reactive carbon-carbon triple bonds and their acetal compounds include: propyne aldehyde, 2-butyn-1-aldehyde, and 2-pentyn-1-aldehyde, etc., which have carbon-carbon triple bonds and their acetal compounds.

[0052] Among the aforementioned aldehydes having multiple bonds and their acetal derivatives, it is preferred to be an aldehyde having a reactive carbon-carbon double bond, preferably selected, for example, from one or more of acrolein, methacrolein, crotonaldehyde, 3-butenal, 2-methyl-2-butenal, 2-methyl-3-butenal, 2,2-dimethyl-3-butenal, 3-methyl-2-butenal, 3-methyl-3-butenal, 2-pentenal, 2-methyl-2-pentenal, 3-pentenal, 3-methyl-4-pentenal, 4-pentenal, 4-methyl-4-pentenal, 2-hexenal, 3-hexenal, 4-hexenal, 5-hexenal, 7-octenal, 2-ethylcrotonaldehyde, 3-(dimethylamino)propenal, and 2,4-pentadienal. Among them, since the copolymerization has good reactivity, it is more preferably selected from one or more of acrolein, methacrolein, crotonaldehyde, and 3-butenal.

[0053] Examples of the aforementioned monocarboxylic acids having multiple bonds, salts of the monocarboxylic acid, esters of the monocarboxylic acid, and anhydrides of the monocarboxylic acid include: (meth)acrylic acid, sodium salts of (meth)acrylic acid, potassium salts of (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, propyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, vinyl (meth)acrylate, 2-(trifluoro) Methacrylic acid, methyl 2-trifluoromethacrylate, ethyl 2-trifluoromethacrylate, propyl 2-trifluoromethacrylate, 2-butyl 2-trifluoromethacrylate, 2-hydroxyethyl 2-trifluoromethacrylate, vinyl 2-trifluoromethacrylate, methyl cinnamate, vinyl cinnamate, methyl crotonate, vinyl crotonate, methyl 3-methyl-3-butenoate, vinyl 3-methyl-3-butenoate, methyl 4-pentenoate, vinyl 4-pentenoate, methyl 2-methyl-4-pentenoate, vinyl 2-methyl-4-pentenoate, methyl 5-hexenoate, vinyl 5-hexenoate, methyl 3,3-dimethyl-4-pentenoate, methyl 3,3- Dimethyl-4-pentenoic acid vinyl ester, methyl 7-octenate, methyl 7-octenate vinyl ester, trans-3-pentenoate methyl ester, trans-3-pentenoate vinyl ester, trans-4-decenoate methyl ester, trans-4-decenoate vinyl ester, ethyl 3-methyl-3-butenoate, ethyl 4-pentenoate, ethyl 2-methyl-4-pentenoate, ethyl 5-hexenoate, ethyl 3,3-dimethyl-4-pentenoate, ethyl 7-octenate, ethyl trans-3-pentenoate, ethyl trans-4-decenoate, methyl 10-undecenoate, vinyl 10-undecenoate, (meth)acrylic anhydride, 2-(trifluoromethyl)acrylic anhydride, cinnamic anhydride, crotonic anhydride, 3-methyl-3 - Butenoic anhydride, 4-pentenoic anhydride, 2-methyl-4-pentenoic anhydride, 5-hexenoic anhydride, 3,3-dimethyl-4-pentenoic anhydride, 7-octenic anhydride, trans-3-pentenoic anhydride, trans-4-decenoic anhydride, 3-methyl-3-butenoic anhydride, 4-pentenoic anhydride, 2-methyl-4-pentenoic anhydride, and 10-undecenoic anhydride, and other carboxylic acids having reactive carbon-carbon double bonds, their salts, esters, and anhydrides; propynic acid, methyl propynate, ethyl propynate, vinyl propynate, butynic acid, methyl butynate, ethyl butynate, and vinyl butynate, and other carboxylic acids having reactive carbon-carbon triple bonds and their esters. In this specification, the term "(meth)acrylic acid" refers to the collective term for "acrylic acid" and "methacrylic acid".

[0054] Examples of dicarboxylic acids having multiple bonds, salts of the aforementioned dicarboxylic acids, esters of the aforementioned dicarboxylic acids, and anhydrides of the aforementioned dicarboxylic acids include, for example: maleic acid, sodium maleate, potassium maleate, methyl maleate, dimethyl maleate, maleic anhydride, icosinic acid, methyl icosinic acid, dimethyl icosinic acid, icosinic anhydride, nadic acid, methyl nadic acid, dimethyl nadic acid, and nadic anhydride, which are dicarboxylic acids having reactive carbon-carbon double bonds, salts of the aforementioned dicarboxylic acids, esters of the aforementioned dicarboxylic acids, and anhydrides of the aforementioned dicarboxylic acids.

[0055] The aforementioned monocarboxylic acid having multiple bonds, salts of the monocarboxylic acid, esters of the monocarboxylic acid, anhydrides of the monocarboxylic acid, dicarboxylic acid having multiple bonds, salts of the dicarboxylic acid, esters of the dicarboxylic acid, and anhydrides of the dicarboxylic acid are preferably compounds having reactive carbon-carbon double bonds. Since the reactivity during copolymerization is good, it is more preferably selected from methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, vinyl (meth)acrylate, (meth)acrylic anhydride, 2-(trifluoromethyl)acrylic anhydride, cinnamic anhydride, crotonic anhydride, methyl maleate, dimethyl maleate, maleic anhydride, methyl itconate, dimethyl itconate, and itconic anhydride.

[0056] Among the aforementioned amine compounds having multiple bonds, examples of amine compounds having reactive carbon-carbon double bonds include: allylamine, 3-butenamine, 4-pentenamine, 5-hexenamine, 6-heptenamine, 7-octenamine, oleylamine, 2-methylallylamine, 4-aminostyrene, 4-vinylbenzylamine, 2-allylglycine, S-allylcysteine, α-allylalylalanine, 2-allylaniline, geraniline, vigabatrin, 4-vinylaniline, and 4-hydroxyaniline. Among these, due to their good reactivity during copolymerization, it is preferable to select one or more of allylamine, 3-butenamine, and 4-pentenamine.

[0057] [Method for manufacturing modified conjugated diene rubber (4)] The manufacturing method (4) is a method of adding a modifying compound that can react with the polymerizing active end before adding a polymerization inhibitor to the polymerized product (unmodified conjugated diene rubber) of an unmodified conjugated diene monomer with a polymerization active end. The unmodified conjugated diene rubber with a polymerization active end is the same as that described in the manufacturing method (1), for example, it can be obtained by polymerizing the conjugated diene monomer and other monomers other than the conjugated diene as needed by emulsion polymerization or solution polymerization. Examples of modifying compounds that can be used in manufacturing method (4) include: dimethyldiethoxysilane, tetramethoxysilane, tetraethoxysilane, 3-aminopropyltriethoxysilane, tetracyclooxypropyl-1,3-diaminomethylcyclohexane, 2,4-toluene diisocyanate, carbon dioxide, ethylene oxide, succinic anhydride, triethyl borate, tripropyl borate, triisopropyl borate, tributyl borate and other organoboroates, organoboroanhydrides, benzene organoboroanhydrides and other organoboroanhydrides, 4,4'-bis(diethylamine)diphenyl ketone, N-vinylpyrrolidone, N-methylpyrrolidone, 4-dimethylaminobenzylmethylaniline, dimethylimidazolidine ketone and other modifiers, or other modifiers described in Japanese Patent Application Publication No. 2011-132298.

[0058] The amount of the aforementioned modified compound used in manufacturing method (4), for example in the case of using an organoalkali metal compound for polymerization, is preferably in the range of 0.01 to 100 molar equivalents relative to the organoalkali metal compound. The reaction temperature is usually -80 to 150°C, preferably 0 to 100°C, and more preferably in the range of 10 to 90°C. Furthermore, after adding the aforementioned modified compound before adding the polymerization inhibitor to introduce hydrogen-bonded functional groups into the unmodified conjugated diene rubber, a modified compound that can react with the functional group can be further added to introduce other hydrogen-bonded functional groups into the polymer.

[0059] Modified conjugated diene rubber may also include units derived from other monomers besides the aforementioned conjugated diene monomers and free radical polymerizable compounds with hydrogen-bonding functional groups, provided that such inclusions do not impair the effects of the present invention. Examples of other monomers include copolymerizable vinyl unsaturated monomers and aromatic vinyl compounds, with the specific compounds and contents being the same as described above.

[0060] There are no particular restrictions on the manufacturing method of modified conjugated diene rubber. However, from a production point of view, it is preferable to manufacture it by manufacturing method (1), (2) or (3), even more preferably by manufacturing method (1) or (3), and even more preferably by manufacturing method (1).

[0061] [Physical Properties of Liquid Conjugated Diene Rubber] The weight-average molecular weight (Mw) of the liquid conjugated diene rubber, from the viewpoint of improving adhesion when the emulsion composition is used as an adhesive, is preferably 2,000 or more, more preferably 5,000 or more, even more preferably 10,000 or more, even more preferably 15,000 or more, even more preferably 20,000 or more, and particularly preferably 25,000 or more. Furthermore, from the viewpoint of maintaining adhesion over a long period, it is even more preferably 35,000 or more. From the viewpoint of improving the processability of the liquid conjugated diene rubber, it is preferably 150,000 or less, more preferably 120,000 or less, even more preferably 100,000 or less, and even more preferably 75,000 or less. The weight-average molecular weight and number-average molecular weight of polystyrene converted from Mw and Mn components of liquid conjugated diene rubbers were determined by gel permeation chromatography (GPC).

[0062] The molecular weight distribution (Mw / Mn) of the liquid conjugated diene rubber is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, even more preferably 1.0 to 2.0, and still more preferably 1.0 to 1.3. If Mw / Mn is within the aforementioned range, the viscosity difference of the liquid conjugated diene rubber is small, making it easier to handle. The molecular weight distribution (Mw / Mn) is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of standard polystyrene obtained by GPC determination.

[0063] The glass transition temperature (Tg) of the liquid conjugated diene rubber may vary depending on the vinyl content of the conjugated diene unit, the type of conjugated diene, and the content of units derived from monomers other than the conjugated diene. It is preferably -100 to 10°C, more preferably -100 to -10°C, and even more preferably -100 to -20°C. If Tg is within the aforementioned range, high viscosity can be suppressed, making it easier to handle. The glass transition temperature (Tg) of the liquid conjugated diene rubber refers to the value measured by differential scanning calorimetry (DSC), specifically, it can be measured by the method described in the examples.

[0064] <Diluent with a vapor pressure of 10 Pa or less at 20°C> In this invention, the diluent is one with a vapor pressure of 10 Pa or less at 20°C. There are no particular limitations on the specific diluent, and examples include oil and low-viscosity liquid rubber. In this invention, low-viscosity liquid rubber refers to rubber with a melt viscosity of less than 30 Pa·s measured at 38°C, which differs from the aforementioned liquid conjugated diene rubber in terms of melt viscosity. Furthermore, in this specification, "diluent with a vapor pressure of 10 Pa or less at 20°C" may be simply referred to as "diluent".

[0065] If the vapor pressure of the aforementioned diluent at 20°C is greater than 10 Pa, it becomes difficult to stabilize the emulsion. Furthermore, when the emulsion composition of the present invention is used as an adhesive, it becomes easier to form coating spots, thus reducing adhesion. Furthermore, there is a possibility of contamination of manufacturing equipment during manufacturing. From these points of view, the vapor pressure of the diluent at 20°C is preferably 5.0 Pa or less, more preferably 1.0 Pa or less, even more preferably 1.0 × 10⁻¹ Pa or less, even more preferably 1.0 × 10⁻² Pa or less, and even more preferably 1.0 × 10⁻³ Pa or less. Also, the vapor pressure of the diluent at 20°C is preferably 1.0 × 10⁻⁸ Pa or more. Wherein, in the present invention, the vapor pressure of the diluent at 20°C being less than 10³ Pa refers to the value calculated from the optimal curve obtained by applying the Antoine equation to the measured value determined by the gas saturation method. Furthermore, the vapor pressure of a diluent at 20°C that is greater than 103 Pa refers to the value directly measured by the static method.

[0066] [Oil] As the aforementioned diluent, a non-volatile oil is preferred. There are no particular limitations on the aforementioned oil, as long as it has a vapor pressure of 10 Pa or less at 20°C and is compatible with liquid conjugated diene rubber; examples include natural oils and synthetic oils. Examples of natural oils include mineral oils and vegetable oils. Examples of mineral oils include paraffinic mineral oils, aromatic mineral oils, and naphthenic mineral oils obtained by conventional refining methods such as solvent refining and hydrogenation refining. In addition, there are waxes (gas-to-liquid waxes) produced by the Fisher-Quebec process, and mineral oils produced by isomerizing waxes. Commercially available paraffinic mineral oil products include: the "Diana Process Oil" series manufactured by Idemitsu Kosan Co., Ltd., the "Super Oil" series manufactured by JX Energy Co., Ltd., and "SUNPAR150" manufactured by Japan Taiyo Oil Co., Ltd. In addition, commercially available naphthenic mineral oils include "SUNTHENE250J" manufactured by Japan Taiyo Oil Co., Ltd.

[0067] Examples of vegetable oils include: linseed oil, camellia seed oil, macadamia nut oil, corn oil, mink oil, olive oil, avocado oil, camellia oil, castor oil, safflower oil, jojoba oil, sunflower oil, almond oil, rapeseed oil, sesame oil, soybean oil, peanut oil, cottonseed oil, coconut oil, palm kernel oil, and rice bran oil. Examples of synthetic oils include: hydrocarbon-based synthetic oils, ester-based synthetic oils, and ether-based synthetic oils. Examples of hydrocarbon-based synthetic oils include: polybutene, polyisobutylene, 1-octene oligomers, 1-decene oligomers, and α-olefin oligomers such as ethylene-propylene copolymers or their hydrogenated derivatives, alkylbenzenes, and alkylnaphthalenes. Examples of ester-based synthetic oils include: triglycerides, diglycerides, monoglycerides, monohydric alcohol fatty acid esters, and polyhydric alcohol fatty acid esters. Examples of ether-based synthetic oils include: polyoxyethylene glycol and polyphenylene ether. Commercially available synthetic oils include: the "LINEALENE" series manufactured by Idemitsu Kosan Co., Ltd., and "FGC32", "FGC46", and "FGC68" manufactured by ANDEROL.

[0068] The oil may be made from one of the aforementioned natural oils and synthetic oils, or it may be a mixture of two or more natural oils, two or more synthetic oils, or one or more natural oils and one or more synthetic oils.

[0069] From a safety point of view, the flash point of the oil used in this invention is preferably above 70°C, more preferably above 100°C, even more preferably above 130°C, and still more preferably above 140°C. There is no particular limitation on the upper limit of the flash point of the oil, but it is preferably below 320°C.

[0070] [Low-viscosity liquid rubber] Low-viscosity liquid rubber is preferred as a diluent. There are no particular limitations on the type of low-viscosity liquid rubber, as long as its melt viscosity measured at 38°C is less than 30 Pa·s and its vapor pressure at 20°C is less than 10 Pa. More specifically, examples include liquid butadiene rubber, liquid isoprene rubber, and liquid chlorophyllin rubber, which can be homopolymers (homogeneous polymers) or copolymers. Low viscosity is particularly preferred for dilution purposes; low molecular weight liquid rubber is preferred, especially liquid butadiene rubber and liquid chlorophyllin rubber.

[0071] When the low-viscosity liquid rubber is liquid butadiene rubber, the weight-average molecular weight is preferably 500 to 10,000, more preferably 700 to 7,000, and even more preferably 800 to 6,000. On the other hand, when the low-viscosity liquid rubber is liquid chlorophyllin rubber, the weight-average molecular weight is preferably 1,000 to 80,000, more preferably 1,000 to 50,000, more preferably 1,000 to 30,000, and even more preferably 1,000 to 10,000. If the weight-average molecular weight of the low-viscosity liquid rubber is within the aforementioned ranges, the stability of the emulsion will be further improved, and the processability of the emulsion composition will also be improved. The weight-average molecular weight of the low-viscosity liquid rubber is the weight-average molecular weight converted from polystyrene obtained by gel permeation chromatography (GPC).

[0072] In this invention, from the viewpoint of the stability of the emulsion and the improvement of the adhesion of the adhesive used in the emulsion composition, the aforementioned diluent is preferably a naphthenic mineral oil or a low-viscosity liquid rubber, and more preferably a naphthenic mineral oil or a liquid butadiene rubber.

[0073] <Surfactant> There are no particular limitations on the surfactants used in this invention, and examples include: cationic surfactants, anionic surfactants, nonionic surfactants, and amphoteric surfactants. Among these, nonionic surfactants are preferred from the viewpoint of improving the stability of the emulsion. One type may be used alone, or two or more may be used in combination.

[0074] Examples of cationic surfactants include: alkylammonium acetates, alkyldimethylbenzylammonium salts, alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkylpyridinium salts, oxyalkylalkylamines, and polyoxyalkylalkylamines. These cationic surfactants can be used alone, or, as needed, two or more can be combined.

[0075] Examples of anionic surfactants include: carboxylates of fatty acid soaps, sulfates of higher alcohols, sulfates of higher alkyl polyalkyl glycol ethers, sulfates of styrene-modified phenol epoxide adducts, sulfates of alkylphenol epoxide adducts, sulfated oils, sulfated fatty acid esters, sulfated fatty acids, sulfated olefins, alkylbenzene sulfonates, alkylnaphthalene sulfonates, naphthalene sulfonates, formalin condensates of naphthalene sulfonic acid, α-olefin sulfonates, paraffin sulfonates, sulfonates of sulfosuccinate diesters, and higher alcohol phosphates. These anionic surfactants can be used alone, or in combination of two or more as needed. Commercially available anionic surfactants include: "PLYSURF A210B" manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd., and "PHOSPHANOL RD-720N" manufactured by Toho Chemical Co., Ltd.

[0076] Examples of nonionic surfactants include: higher alcohol alkylene oxide adducts, alkylphenol alkylene oxide adducts, styrene-modified phenol alkylene oxide adducts, fatty acid alkylene oxide adducts, polyol aliphatic ester alkylene oxide adducts, higher alkylamine alkylene oxide adducts, fatty acid amide alkylene oxide adducts, and other polyoxyalkylene-type nonionic surfactants; alkyl glycosides, sucrose fatty acid esters, and other polyol-type nonionic surfactants. These nonionic surfactants can be used alone, or, as needed, two or more can be combined. Commercially available nonionic surfactants include: ADEKA TOL PC-6, ADEKA TOL PC-8, ADEKA TOL PC-10, and ADEKA TOL TN-100 manufactured by ADEKA Corporation; and polyoxyethylene alkyl ethers (trade names: Pegnol TE-10A, Pegnol L-9A, and Pegnol TH-8) manufactured by Toho Chemical Industries, Ltd.

[0077] The HLB (Hydrophilic-Lipophilic Balance) value of a nonionic surfactant is an indicator representing the balance between hydrophilicity and lipophilicity, expressed as a value from 0 to 20. In this invention, the value is calculated using the Griffin method according to the following formula (I): HLB value = 20 × total formula weight of the hydrophilic portion / molecular weight (I)

[0078] The identification of nonionic surfactants involves determining the molecular weight and structural units using mass spectrometry, and determining the structure using 1H and 13C-NMR. Since the structure can be identified based on these methods, the HLB value can be calculated using formula (I) based on the identified data. For example, methods for separating nonionic surfactants from emulsion compositions include fractionation and separation by reversed-phase liquid chromatography.

[0079] <Composition of the Emulsion Composition> From the viewpoint of improving the stability of the emulsion and improving the adhesion when the emulsion composition is used as an adhesive, the content of liquid conjugated diene rubber in the emulsion composition of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 4% by mass or more, and preferably 50% by mass or less, even more preferably 30% by mass or less, and even more preferably 20% by mass or less, relative to the total amount of the emulsion composition. If the content of liquid conjugated diene rubber in the emulsion composition is within the aforementioned range, it can improve the stability of the emulsion while preventing the viscosity of the emulsion composition from becoming extremely high.

[0080] The content of the aforementioned diluent in the emulsion composition is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 4% by mass or more, and preferably 50% by mass or less, even more preferably 30% by mass or less, and even more preferably 20% by mass or less, relative to the total amount of the emulsion composition. If the content of the aforementioned diluent in the emulsion composition is within the aforementioned range, it can prevent the viscosity of the emulsion composition from becoming extremely high, thereby improving manufacturing efficiency. Furthermore, due to the improved stability of the emulsion, defects such as phase separation are less likely to occur even after a long period of time after manufacturing.

[0081] The content of the aforementioned surfactant in the emulsion composition is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 4 parts by mass or more, relative to a total of 100 parts by mass of the aforementioned liquid conjugated diene rubber and the aforementioned diluent. If the content of the aforementioned surfactant is 1 part by mass or more, the stability of the emulsion can be improved. On the other hand, from the viewpoint of manufacturing cost, the amount of surfactant is preferably set to 15 parts by mass or less, and more preferably 10 parts by mass or less.

[0082] The aforementioned liquid conjugated diene rubber can be used alone or in combination with two or more. Similarly, the aforementioned diluent can be used alone or in combination with two or more. Furthermore, the aforementioned surfactant can be used alone or in combination with two or more.

[0083] Furthermore, the emulsion composition of the present invention may also include, within a range that does not impair the stability of the emulsion, liquid conjugated diene rubber, a diluent with a vapor pressure of less than 10 Pa at 20°C, a surfactant, and other components other than water. Examples of such other components include: other polymers, acids, alkaline compounds such as sodium hydroxide, antioxidants, curing agents, dispersants, pigments, dyes, adhesives, carbon black, etc.

[0084] Examples of alkaline compounds include sodium hydroxide, potassium hydroxide, sodium carbonate, and ammonia. Among these, sodium hydroxide and ammonia are preferred from the viewpoint of stability and adhesion, while ammonia is preferred from the viewpoint of operator safety.

[0085] In cases where the aforementioned emulsion composition contains other components, the content of such components, relative to 100 parts by weight of liquid conjugated diene rubber, is preferably 1,000 parts by weight or less, more preferably 100 parts by weight or less, and even more preferably 1 part by weight or less. For example, if the emulsion composition contains alkaline compounds such as sodium hydroxide within the aforementioned range, the stability of the emulsion will be further improved.

[0086] [Method for Manufacturing Emulsion Composition] The method for manufacturing an emulsion composition according to the present invention is characterized in that: after mixing the aforementioned liquid conjugated diene rubber, the aforementioned diluent, the aforementioned surfactant, and water to manufacture an oil-water emulsion, the aforementioned diluent is not removed. According to the manufacturing method of the present invention, since a diluent with a vapor pressure of 10 Pa or less at 20°C is used, the viscosity increase of the emulsion composition is suppressed, and an emulsion composition with excellent stability can be obtained more easily than conventional methods. Furthermore, conventional methods using highly volatile solvents require a solvent removal step, while the method of the present invention does not require this removal step to manufacture the emulsion composition. In other words, according to the manufacturing method of the present invention, the emulsion composition can be efficiently utilized in applications such as adhesives without a post-processing step. In the manufacturing method of the present invention, "not removing the diluent" means that there is no need to design a step for removing the diluent.

[0087] The order of mixing the aforementioned liquid conjugated diene rubber, the aforementioned diluent, the aforementioned surfactant, and water is as follows: water is added after mixing the aforementioned liquid conjugated diene rubber, the aforementioned diluent, and the aforementioned surfactant. A more preferred mixing order is: after preparing a diluted solution by mixing the aforementioned liquid conjugated diene rubber and the aforementioned diluent, the aforementioned surfactant is mixed into the aforementioned diluted solution, followed by the continuous addition of water and, as needed, an alkaline compound such as sodium hydroxide, while mixing. The method for manufacturing emulsion compositions using these sequences is generally called the phase inversion emulsification method, which involves dissolving an emulsifier in an oil phase and adding water while stirring to convert the continuous phase from the oil phase to the aqueous phase, thereby generating an O / W type emulsion. When mixing water and, as needed, an alkaline compound such as sodium hydroxide, the phase inversion can be carried out slowly by adding water in small amounts while mixing, resulting in a finer emulsion composition with a smaller particle size distribution. Furthermore, the view that adding alkaline compounds such as sodium hydroxide can improve the storage stability of the resulting emulsion composition is preferably to stop adding the aforementioned alkaline compounds before the phase transition ends.

[0088] When mixing the components in the order of mixing the aforementioned liquid conjugated diene rubber, the aforementioned diluent, and the aforementioned surfactant, and then mixing water therein, it is preferable to perform the mixing by a mechanical method. Examples of such mechanical methods include using a kneader, a high-speed mixer, or a twin-screw extruder, which can be used individually or in combination. By using the aforementioned apparatus, a fine-particle-size emulsion composition can be obtained through strong shearing.

[0089] In cases where the sequence of steps involves mixing the aforementioned liquid conjugated diene rubber and the aforementioned diluent to prepare a diluted solution, then mixing the aforementioned surfactant into the diluted solution, and subsequently adding small amounts of water and, if necessary, an alkaline compound such as sodium hydroxide while mixing, the mixing process is preferably performed as follows. That is, in the steps of mixing the aforementioned liquid conjugated diene rubber and the aforementioned diluent to prepare the diluted solution, and in the step of mixing the aforementioned surfactant into the obtained diluted solution, it is preferable to use a kneader, a high-speed mixer, or a twin-screw extruder for mixing. By using these devices, a uniformly mixed solution can be obtained more easily and with high productivity. In the next step of continuously mixing small amounts of water with alkaline compounds such as sodium hydroxide as needed, preferred mixing methods include using homogenizers, high-speed emulsifiers, dispersion mixers, colloid mills, kneaders, planetary mixers, high-speed mixers, high-pressure homogenizers, twin-screw extruders, and ultrasonic emulsifiers. These methods can be used individually or in combination. By using the above-mentioned devices, a fine-particle-size emulsion composition can be obtained by applying strong shear force.

[0090] In the aforementioned method for manufacturing the emulsion composition, when adding water, water can be added in a single emulsion composition manufacturing step, so that the content of the aforementioned liquid conjugated diene rubber and the aforementioned diluent in the emulsion composition reaches the aforementioned preferred range. In a more preferred embodiment, the manufacturing steps used are divided into two or more steps. In the initial manufacturing step, the amount of water added is limited to include the aforementioned liquid conjugated diene rubber and the aforementioned diluent at a high concentration. Then, in the second and subsequent emulsion composition manufacturing steps, water is further added to make the content of the aforementioned liquid conjugated diene rubber and the aforementioned diluent suitable for the final product. By adopting this manufacturing step, the quality of the final emulsion composition product is easily stabilized. In this manufacturing process, the initial manufacturing step and subsequent steps do not necessarily need to be performed in the same location. The following implementation is also preferable: after transporting the high-concentration emulsion composition obtained from the initial manufacturing step to the location where the emulsion composition is actually used or its vicinity, water is further added in the subsequent manufacturing steps of the emulsion composition to adjust the content of the aforementioned liquid conjugated diene rubber and the aforementioned diluent to suit the final product. In this case, the high-concentration emulsion composition has relatively lower transportation costs, making it more economically advantageous.

[0091] According to the manufacturing method of the present invention, since the viscosity of the aforementioned diluent can be reduced, when emulsifying by the aforementioned mechanical method, the rotation speed can be increased without applying excessive load to the device and sufficient shearing can be provided. From the above viewpoint, the viscosity of the diluent measured at 25°C is preferably 1.0 × 10³ Pa·s or less, more preferably 5.0 × 10² Pa·s or less, even more preferably 1.0 × 10² Pa·s or less, and most preferably 5.0 × 10 Pa·s or less. If the aforementioned viscosity is within the aforementioned range, the manufacturing process is simplified because the viscosity can be sufficiently reduced. Here, the viscosity of the diluent refers to the viscosity measured at 25°C using a Brookfield viscometer (Type B viscometer) using only the composition of the aforementioned conjugated diene rubber and the aforementioned diluent. The rotor and rotation speed during the measurement are appropriately set to be close to full scale.

[0092] <Uses of the Emulsion Composition> Because the emulsion composition of the present invention exhibits high stability as described above, it displays excellent adhesion when used, for example, as an adhesive component. There are no particular limitations on the uses of the emulsion composition of the present invention as an adhesive component; for example, it can be used to bond fibers to rubber.

[0093] [Fibers] There are no particular limitations on the fibers used as the adhesive, but from the viewpoint of affinity with the adhesive using the aforementioned emulsion composition, hydrophilic fibers are preferred. In this invention, "fibers" includes not only monofibers and long fibers, but also nonwoven fabrics, woven fabrics, knitted fabrics, felts, and sponges.

[0094] As a hydrophilic synthetic fiber, examples include: synthetic fibers made of thermoplastic resins having hydrophilic functional groups such as hydroxyl, carboxyl, sulfonic acid and amine groups, and / or hydrophilic bonds such as amide bonds. Specific examples of such thermoplastic resins include: polyvinyl alcohol resins, polyamide resins [aliphatic polyamides such as polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612, and polyamide 9C (a polyamide composed of nonadiamine and cyclohexanedicarboxylic acid); semi-aromatic polyamides such as polyamide 9T (a polyamide composed of nonadiamine and terephthalic acid) synthesized from aromatic dicarboxylic acids and aliphatic diamines; and fully aromatic polyamides such as poly(p-phenylene terephthalamide) synthesized from aromatic dicarboxylic acids and aromatic diamines], and polyacrylamide resins. Among these, polyvinyl alcohol resins and polyamide resins are preferred. Hydrophilic synthetic fibers can be made using one type alone or in combination of two or more types. Furthermore, these hydrophilic synthetic fibers can be further subjected to the hydrophilization treatment described later to further enhance their hydrophilicity.

[0095] Examples of hydrophilic natural fibers include: natural cellulose fibers such as wood pulp (e.g., kraft pulp) or non-wood pulp (e.g., cotton pulp, straw pulp). Examples of hydrophilic regenerated fibers include: regenerated cellulose fibers such as rayon, lyocell, cupro, and polycellulose. These natural and regenerated fibers can be used individually or in combination. Furthermore, to further enhance their hydrophilicity, these hydrophilic natural and regenerated fibers may undergo the hydrophilization treatment described later.

[0096] The hydrophilic fiber only needs to be hydrophilic on its surface. For example, it can be a fiber made by hydrophilizing the surface of a hydrophobic fiber; or a sheath-core type composite fiber in which a hydrophobic resin is used as the core and a hydrophilic resin is used as the sheath. Examples of hydrophilic resins constituting the sheath are cited from the description of hydrophilic synthetic fibers. Examples of hydrophobic fibers containing hydrophobic resins include polyolefin fibers such as polyethylene and polypropylene, polyester fibers such as polyethylene terephthalate, and fully aromatic polyester fibers, among which polyester fibers are preferred.

[0097] Hydrophilic treatment is any treatment that chemically or physically imparts hydrophilic functional groups to the surface of a fiber, and is not particularly limited. It can be carried out by, for example, the following methods: modifying hydrophobic fibers containing the aforementioned hydrophobic resin by using compounds or derivatives of hydrophilic functional groups such as isocyanate groups, epoxy groups, hydroxyl groups, amino groups, ether groups, aldehyde groups, carbonyl groups, carboxyl groups and carbamate groups; and modifying the surface by irradiating with an electron beam, etc.

[0098] From the viewpoint of the ease of fit between the emulsion composition and the fiber, the fibers used in this invention are preferably synthetic fibers and regenerated fibers, and preferably selected from one or more of polyvinyl alcohol fibers, regenerated cellulose fibers, polyester fibers, and polyamide fibers made from polyvinyl alcohol resins. Polyester fibers that have undergone hydrophilic treatment are most preferred.

[0099] [Method for attaching emulsion composition to fibers] There are no particular limitations on the method for attaching emulsion composition to fibers, but it is preferred to do so by one or more methods selected from dip coating, roller coating, oiling roller, oiling guide, nozzle (spray) coating, and brush coating.

[0100] The amount of the aforementioned emulsion composition, from the viewpoint of improving the adhesion between the fiber and the rubber, is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 1 part by mass or more, relative to 100 parts by mass of fiber. From the viewpoint of balancing manufacturing cost and effect, it is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less.

[0101] After attaching the emulsion composition of the present invention to the fiber, it is preferable to let it stand at room temperature of about 20°C for about 3 to 10 days. Alternatively, depending on the situation, the fiber may be heat-treated after attachment. The aforementioned heat treatment is preferably performed at a treatment temperature of 100 to 200°C for a treatment time of 0.1 seconds to 2 minutes. Since the liquid conjugated diene rubber contained in the aforementioned emulsion composition has reactive multi-bonds, heat treatment in the presence of oxygen is preferably performed at 200°C or below, more preferably at 175°C or below. If the heat treatment temperature is within the aforementioned range, the amount of reactive multi-bonds in the liquid conjugated diene rubber will not decrease, thus improving adhesion, further inhibiting fiber deterioration, and improving coloring and other qualities.

[0102] [Rubber] There are no particular restrictions on the rubber bonded to the fiber, and examples include: NR (natural rubber), IR (polyisoprene rubber), BR (polybutadiene rubber), SBR (styrene-butadiene rubber), NBR (nitrile rubber), EPM (ethylene-propylene copolymer rubber), EPDM (ethylene-propylene-non-conjugated diene copolymer rubber), IIR (butyl rubber), halogenated butyl rubber, CR (chloroprene rubber), etc. Among these, NR, BR, and SBR are preferred. These rubbers can be used individually or in combination of two or more.

[0103] As a method for manufacturing a rubber molded article by bonding the aforementioned fibers and the aforementioned rubber, for example, an emulsion composition can be attached to the aforementioned fibers, embedded in the unvulcanized aforementioned rubber composition, and then vulcanized to obtain a molded article formed by bonding the fibers and rubber through the aforementioned emulsion composition. [Example]

[0104] Hereinafter, the present invention will be further described in detail by way of examples, etc., but the present invention is not limited to these examples, etc.

[0105] <Manufacturing of Liquid Conjugated Diene Rubber> Manufacturing Example 1: Manufacturing of Modified Conjugated Diene Rubber (A-1) Nitrogen substitution was carried out in a thoroughly dried 5L high-pressure reactor. 1260g of hexane and 36.3g of n-butyllithium (17% by mass hexane solution) were added. The temperature was raised to 50°C, and under stirring, while maintaining the polymerization temperature at 50°C, 1260g of butadiene was added sequentially, and polymerization was carried out for 1 hour. Then, methanol was added to stop the polymerization reaction, yielding a polymer solution. Water was added to the obtained polymer solution and stirred to wash the polymer solution clean with water. After stirring was stopped, and the polymer solution phase and water phase were confirmed to be separated, the water was separated. The washed polymer solution was vacuum dried at 70°C for 24 hours to obtain unmodified liquid polybutadiene (A'-1). Next, 500g of the obtained unmodified liquid polybutadiene (A'-1) was added to a 1L high-pressure reactor for nitrogen substitution, along with 25g of maleic anhydride and 0.5g of N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (trade name "Nocrack 6C", manufactured by Daichi Shinsei Chemical Co., Ltd.). The mixture was reacted at 170°C for 24 hours to obtain maleic anhydride-modified liquid polybutadiene. 8.5g of methanol was added to 525g of the obtained maleic anhydride-modified liquid polybutadiene, and the mixture was reacted at 80°C for 6 hours to obtain maleic acid monomethyl ester-modified liquid polybutadiene (A-1).

[0106] Manufacturing Example 2: Modified conjugated diene rubber (A-2) was manufactured in the same manner as in Manufacturing Example 1, except that 1260g of hexane and 23.6g of n-butyllithium (17% by mass hexane solution) were added, the temperature was raised to 50°C, and under stirring conditions, the polymerization temperature was controlled at 50°C while 1260g of butadiene was added sequentially.

[0107] <Manufacturing of Low-Viscosity Liquid Rubber> Manufacturing Example 3: Manufacturing of Low-Viscosity Liquid Butadiene Rubber (B-1) A nitrogen substitution reaction was carried out in a thoroughly dried 5L high-pressure reactor. 1260g of hexane and 166g of n-butyllithium (17% by mass hexane solution) were added. After heating to 50°C, under stirring, while maintaining the polymerization temperature at 50°C, 1260g of butadiene was added sequentially, and polymerization was carried out for 1 hour. Then, methanol was added to stop the polymerization reaction, resulting in a polymer solution. Water was added to the obtained polymer solution and stirred to wash the polymer solution clean with water. After stirring was stopped, and the polymer solution phase and water phase were confirmed to be separated, the water was separated. The washed polymer solution was vacuum dried at 70°C for 24 hours to obtain low-viscosity liquid butadiene rubber (B-1).

[0108] The determination and calculation methods for various physical properties of modified conjugated diene rubbers, etc., are shown below. The results are shown in Table 1. <Determination methods for weight-average molecular weight, number-average molecular weight, and molecular weight distribution> The Mw, Mn, and Mw / Mn of modified conjugated diene rubbers, etc., were obtained by using GPC (gel permeation chromatography) as the conversion value for standard polystyrene. The determination apparatus and conditions are shown below. ･Apparatus: GPC apparatus "GPC8020" manufactured by Tosoh Corporation ･Separation column: "TSKgelG4000HXL" manufactured by Tosoh Corporation ･Detector: "RI-8020" manufactured by Tosoh Corporation ･Liquid: Tetrahydrofuran ･Liquid flow rate: 1.0 ml / min ･Sample concentration: 5 mg / 10 ml ･Column temperature: 40℃

[0109] <Method for determining melting viscosity> The melting viscosity of modified conjugated diene rubber and the like at 38°C was determined by a Brookfield viscometer (manufactured by BROOKFIELD ENGINEERING LABS. INC.).

[0110] <Method for determining glass transition temperature> 10 mg of modified conjugated diene rubber was sampled into an aluminum pot, and the temperature was recorded by differential scanning calorimetry (DSC) at a heating rate of 10 °C / min. The peak value of the DDSC was taken as the glass transition temperature.

[0111] <Average Number of Hydrogen-Bonded Functional Groups per Molecule> The average number of hydrogen-bonded functional groups per molecule of modified conjugated diene rubber is calculated by the equivalent (g / eq) of the hydrogen-bonded functional groups of the modified conjugated diene rubber and the number average molecular weight Mn converted from styrene, using the following formula: Average number of hydrogen-bonded functional groups per molecule = [(number average molecular weight (Mn)) / (molecular weight of styrene unit) × (average molecular weight of conjugated diene and other monomer units other than conjugated diene included as needed)] / (equivalent of hydrogen-bonded functional groups) Wherein, the method for calculating the equivalent of hydrogen-bonded functional groups can be appropriately selected according to the type of hydrogen-bonded functional groups.

[0112] The average number of hydrogen-bonded functional groups per molecule of modified conjugated diene rubber is calculated by determining the acid value of the modified conjugated diene rubber and then calculating the equivalent number (g / eq) of the hydrogen-bonded functional groups from the acid value. The modified sample was washed four times with methanol (5 mL for 1 g of sample) to remove antioxidants and other impurities. The sample was then dried under reduced pressure at 80°C for 12 hours. 3 g of the modified sample was dissolved in 180 mL of toluene and 20 mL of ethanol, neutralized and titrated with a 0.1 N potassium hydroxide ethanol solution, and the acid value was calculated using the following formula. Acid value (mgKOH / g) = (AB) × F × 5.611 / SA: Titration volume of 0.1N potassium hydroxide ethanol solution required for neutralization (mL) B: Titration volume of 0.1N potassium hydroxide ethanol solution in a blank sample (mL) F: Titration concentration of 0.1N potassium hydroxide ethanol solution S: Mass of sample weighed (g)

[0113] Calculate the mass of hydrogen-bonded functional groups in 1g of modified conjugated diene rubber from the acid value using the following formula, and further calculate the mass of the polymer backbone (excluding functional groups) in 1g of modified conjugated diene rubber. Then, calculate the equivalent amount (g / eq) of the hydrogen-bonded functional groups using the following formula: [Mass of hydrogen-bonded functional groups per 1g] = [Acid value] / [56.11] × [Molecular weight of hydrogen-bonded functional groups] / 1000 [Mass of polymer backbone per 1g] = 1 - [Mass of hydrogen-bonded functional groups per 1g] [Equivalent amount of hydrogen-bonded functional groups] = [Mass of polymer backbone per 1g] / ([Mass of hydrogen-bonded functional groups per 1g] / [Molecular weight of hydrogen-bonded functional groups])

[0114] [Table 1] liquid Conjugated dienes rubber Modified base Mw (×10 3 ) Mn (×10 3 ) molecular weight distributed Mw / Mn At 38℃ Melting viscosity (Pa・s) Glass Transfer temperature (°C) vinyl content (mol%) Each molecule Average hydrogen bonding Functional cardinality (number) A-1 Monomethyl maleate 31 29 1.07 197 -88 10 7 A-2 Monomethyl maleate 52 45 1.14 2016 -87 10 12

[0115] The components used in the examples and comparative examples are as described in Tables 2 and 3. [Table 2] diluent or organic solvent Product Name type 20℃ vapor pressure (Pa) Melting viscosity at 38℃ (Pa･s) average weight molecular weight Example 1 SUNTHENE250J Naphthenic oils 1.0×10 -1 - - 2 SUNTHENE250J Naphthenic oils 1.0×10 -1 - - 3 Low-viscosity liquid butadiene rubber (B-1) Liquid butadiene rubber <1.0×10 -7 0.6 5,500 4 Low-viscosity liquid butadiene rubber (B-1) Liquid butadiene rubber <1.0×10 -7 0.6 5,500 5 SUNPAR150 Paraffin oil 1.0×10 -2 - - 6 SUNPAR150 Paraffin oil 1.0×10 -2 - - 7 SUNTHENE250J Naphthenic oils 1.0×10 -1 - - 8 SUNTHENE250J Naphthenic oils 1.0×10 -1 - - Comparative example 1 - - - - - 2 Toluene organic solvents 2.9×10 3 - - 3 Toluene organic solvents 2.9×10 3 - - Note 1) "SUNTHENE250J" and "SUNPAR150" are manufactured by Japan Sun Oil Co., Ltd.

[0116] [Table 3] surfactants Product Name type HLB Example 1 TE-10A nonionic 14.1 2 TE-10A nonionic 14.1 3 TE-10A nonionic 14.1 4 TE-10A nonionic 14.1 5 TN-100 nonionic 13.8 6 TN-100 nonionic 13.8 7 TE-10A nonionic 14.1 8 TE-10A nonionic 14.1 Comparative example 1 TE-10A nonionic 14.1 2 TE-10A nonionic 14.1 3 TE-10A nonionic 14.1 Note 1) "TE-10A" is manufactured by Toho Chemical Industry Co., Ltd. Note 2) "TN-100" is manufactured by ADEKA Corporation.

[0117] The vapor pressures of the diluents at 20°C in Table 2 and the HLB values ​​of the surfactants in Table 3 were determined according to the following methods. [Vapor pressure of diluents at 20°C] The vapor pressures of synthetic oils and mineral oils at 20°C were calculated based on the measured values ​​obtained by the gas saturation method, using constants A, B, and C from the Antoine equation: log10P = A - (B / (T+C)). The vapor pressure of toluene at 20°C was determined directly by the static method.

[0118] [HLB Value of Surfactants] The identification of nonionic surfactants involves determining their molecular weight and structural units using mass spectrometry, and determining their structure using 1H and 13C-NMR. The HLB value is then calculated using the following formula (I) based on the identified data: HLB = 20 × (total formula weight of hydrophilic portion) / molecular weight (I)

[0119] <Example 1: Preparation of Emulsion> Modified conjugated diene rubber (A-1) as a liquid conjugated diene rubber was mixed with naphthenic oil (trade name "SUNTHENE250J", manufactured by Taiyo Oil Co., Ltd., Japan, vapor pressure at 20°C: 1.0×10-1Pa) as a diluent (oil) with a vapor pressure of less than 10Pa at 20°C, in the proportions shown in Table 4. The mixture was stirred for 24 hours at 50°C to prepare 300g of oil dilution of modified conjugated diene rubber (A-1). Next, 18g of polyoxyethylene alkyl ether (trade name "TE-10A", manufactured by Toho Chemical Co., Ltd., HLB value: 14.1) as a surfactant and 0.6g of 50% sodium hydroxide aqueous solution were added to the aforementioned oil dilution and stirred for 10 minutes. Next, while stirring, 210g of water was continuously added in small amounts and stirred for 60 minutes to obtain the emulsion composition (E-1) of the modified conjugated diene rubber (A-1).

[0120] <Examples 2-4, 7-8, Comparative Examples 1-3: Preparation of Emulsion Composition> Except that the formulation of each component is as shown in Table 4, the emulsion composition was prepared in the same manner as in Example 1.

[0121] <Examples 5-6: Preparation of Emulsion Composition> Except that the formulation of each component is as shown in Table 4, and ethoxylated primary alcohol (trade name "TN-100", manufactured by ADEKA Co., Ltd., HLB: 13.8) is used as a surfactant, the emulsion composition is prepared in the same way as in Example 1.

[0122] [Evaluation] <Manufacturability (Viscosity at Dilution)> In the examples and comparative examples, the viscosity of the diluted solution immediately after mixing the liquid conjugated diene rubber and the diluent was measured using a rotary B-type viscometer (100 rpm). The measurement was performed at room temperature (25°C). Lower viscosity indicates easier manufacturing. In this invention, "manufacturability" refers to the ability to easily manufacture emulsion compositions with excellent stability; specifically, it means that the viscosity does not become excessively high when mixing the liquid conjugated diene rubber and the diluent, demonstrating excellent processability and ease of manufacturing.

[0123] <Stability of Emulsion Compositions> After preparing the emulsion compositions of the Examples and Comparative Examples, they were placed in sample vials and allowed to stand at room temperature (25°C) for 1 day. The emulsion compositions in the sample vials were visually observed, and the volume of phase separation in the total volume of the emulsion composition was evaluated according to the following criteria. The results are shown in Table 4.

[0124] [Benchmark] A: Phase separation rate is less than 10% of the total volume, indicating excellent stability. B: Phase separation rate is more than 10% and less than 50% of the total volume, indicating slightly insufficient stability. C: Phase separation rate is more than 50% of the total volume, indicating insufficient stability.

[0125] <Adhesion to Polyester Fibers> Regarding the adhesion to polyester fibers, reinforced fibers were prepared in the following order, and then evaluation samples were prepared. Among them, the evaluation of the adhesion to polyester fibers was conducted only on Examples 1, 3, 5 and Comparative Examples 1, 2, where the sum of the amounts of liquid conjugated diene rubber, diluent, surfactant, and sodium hydroxide in the formulations in Table 4 was 10% by mass of the total (emulsion composition). The results are shown in Table 4. (1) Manufacturing of reinforced fibers [Constitutes of surface modification layer (surface modifier)] First, the constituent material of the surface modification layer (C-1) was prepared by mixing the following components. ･End-capped isocyanate compound: 2.29 parts by mass ･Epoxy compound: 0.8 parts by mass ･Water: 96.91 parts by mass

[0126] Details of the compounds used for C-1 are described below.・ Capping isocyanate compound MEIKANATE DM-3031 CONC (made by Mingcheng Chemical Industry Co., Ltd., purity 54 mass%) ・Epoxy compound DENACOL EX-614B (made by Nagase ChemteX Co., Ltd., purity 100 mass%)

[0127] [Treatment of the ligand] Next, the following ligand is treated with the constituent material (C-1) of the aforementioned surface reforming layer. Specifically, the fiber line was prepared by applying the upper pin 470 times / m and the lower pin 470 times / m to two PET fibers belonging to the polyester-based fiber (total fiber 1100 dtex, monofilament fiber 6.10 dtex). Next, after impregnating the aforementioned ligatures in the constituent material (C-1) of the surface reforming layer, the extraction was carried out with a roller. The obtained fiber line was prepared by drying at 140°C for 60 seconds and further heat treatment at 240°C for 60 seconds.

[0128] Next, the obtained fiber lines were impregnated in an emulsion containing reformed conjugated diene-based rubber (A-1) or reformed conjugated diene-based rubber (A-2), and reinforced fibers were prepared by squeezing the liquid in a roller and then rolling at 140°C for 60 seconds.

[0129] (2) Evaluation Using the preparation of the sample, three prepared reinforced fibers were arranged at certain intervals in an unvulcanized rubber composition of NR / SBR prepared by resorting to the formulation described later. Next, a sample for evaluation was prepared by pressurizing vulcanization at 150°C and a pressure of 20kg / cm2 for 30 minutes.

[0130] [Formulation composition of NR / SBR unvulcanized rubber] NR rubber: 70 parts by mass SBR rubber: 41.25 parts by mass Filler (carbon black): 45 parts by mass Vulcanizing agent (sulfur powder): 3.5 parts by mass Vulcanization additive (zinc white, stearic acid): 6 parts by mass Thiazole system) Promoter:

[0131] (3) Finally, the force (N / 3 strips) required to peel the obtained evaluation sample from the rubber T-shape was measured, and the fiber adhesion was evaluated as the rubber adhesion force. The results are shown in Table 4. The larger the coefficient value of the rubber adhesion force evaluation result, the greater the adhesion force between the reinforcing fiber and the rubber. [Benchmark] A: The adhesion of polyester fibers is 70 N / 3 strips or more. B: The adhesion of polyester fibers is 40 N / 3 strips or more, but less than 70 N / 3 strips. C: The adhesion of polyester fibers is less than 40 N / 3 strips. Wherein, the values ​​in parentheses in the table are the aforementioned measured values ​​(N / 3 strips).

[0132] [Table 4] Example Comparative example 1 2 3 4 5 6 1 2 3 Composition of the emulsion (parts by mass) liquid conjugation Diene-based rubbers Manufacturing Example 1 28 28 28 28 28 28 56 28 28 Manufacturing Example 2 The vapor pressure at 20°C is Diluents below 10 Pa Naphthenic oils 28 28 Paraffin oil 28 28 Low viscosity liquid rubber 28 28 organic solvents (The vapor pressure at 20°C is greater than 10 Pa) Toluene 28 28 water 540 140 540 140 540 140 540 540 140 surfactants 3 3 3 3 3 3 3 3 3 Sodium hydroxide 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 total 599.1 199.1 599.1 199.1 599.1 199.1 599.1 599.1 199.1 Content (mass%) of conjugated diene rubber in emulsion composition 4.7 14.1 4.7 14.1 4.7 14.1 9.3 4.7 14.1 Content of diluent in emulsion composition (mass %) 4.7 14.1 4.7 14.1 4.7 14.1 0.0 0.0 0.0 evaluate Ease of manufacture [viscosity at dilution (Pa·s)] 67 67 40 40 90 90 320 1.4 1.4 lotion Stability of the composition A A A A A A A C B Adhesion [Adhesion to polyester fibers (N / 3 strips)] A (94) - A (75) - A (98) - B (68) - Unable to determine 1) 1) Lack of stability prevents bonding tests from being conducted.

[0133] <Sustainability to polyamide-based fibers> Regarding the subsistence to polyamide-based fibers, the fortified fibers were prepared in the following order, and a sample for evaluation was next prepared. Wherein, the evaluation of the adherence of the polyamide-based fibers was performed only for Example 7 in which the formulation of the liquid conjugated diene-based rubber, diluent, surfactant, and sodium hydroxide in the formulation of Table 5 sums to 10 mass% of the whole body (emulsion composition). The results are shown in Table 5 .

[0134] (1) Manufacture of reinforced fibers [constituent material of the surface reforming layer (surface reforming agent)] First, by mixing each of the following components, the constituent material of the surface reforming layer (D-1) is prepared.・Polyethylene imine compound: 0.01 parts by mass ・Water: 99.99 parts by mass

[0135] Details of the compounds used for D-1 are described below.・Polyethyleneimine compound (SP-200 made by Nippon Catalyst Co., Ltd.)

[0136] [Treatment of ligatures] Next, the constituent material (D-1) of the aforementioned surface reforming layer is treated with the ligands. Specifically, 470 times / m of upper pins and 470 times / m of lower pins were applied to two resistant fibers belonging to polyamide-based fibers (total fibers of 1400 dtex and monofilament fibers of 6.86 dtex). Next, after impregnating the aforementioned ligature in the constituent material (D-1) of the surface reforming layer, the extraction was carried out with a roller. The obtained fiber line was prepared by drying at 140°C for 60 seconds and further heat-treating at 210°C for 60 seconds.

[0137] Next, the obtained fiber lines were impregnated in an emulsion containing modified conjugated diene-based rubber (A-2), and reinforced fibers were prepared by rolling the liquid in a rolling roll and drying at 140°C for 60 seconds.

[0138] [Table 5] Embodiment 7 8 Composition of the emulsion composition (mass fraction) Liquid conjugation Diene-based rubber Manufacturing Example 1 Manufacturing Example 2 28 28 The vapor pressure at 20°C is Diluents below 10 Pa Naphthenic oils 28 28 Paraffin oil Low viscosity liquid rubber organic solvents (The vapor pressure at 20°C is greater than 10 Pa) Toluene water 540 140 surfactants 3 3 Sodium hydroxide 0.1 0.1 total 599.1 199.1 Content (mass%) of conjugated diene rubber in emulsion composition 4.7 14.1 Content of diluent in emulsion composition (mass %) 4.7 14.1 evaluate Ease of manufacture [viscosity at dilution (Pa·s)] 468 468 lotion Stability of the composition A A Adhesion [Adhesion to polyamide fibers (N / 3 strands)] 63 -

[0139] As can be clearly seen from the description of the examples and comparative examples, an emulsion composition with excellent emulsion stability can be obtained according to the present invention. Furthermore, it is known that when the emulsion composition of the present invention is used for bonding, excellent adhesion is exhibited. [Simplified Explanation of the Diagram]

[0012] None.

Claims

1. An emulsion composition comprising: a liquid conjugated diene rubber, a diluent having a vapor pressure of less than 10 Pa at 20°C, a surfactant, an alkaline compound selected from at least one of sodium hydroxide and ammonia, and water, wherein the emulsion is an oil-in-water emulsion.

2. The emulsion composition of claim 1, wherein the liquid conjugated diene rubber comprises one or more monomer units derived from butadiene, isoprene and β-chlorophyllin.

3. The emulsion composition of claim 1 or 2, wherein the liquid conjugated diene rubber is a modified conjugated diene rubber having hydrogen-bonded functional groups in a portion of the conjugated diene rubber.

4. The emulsion composition of claim 3, wherein the hydrogen-bonding functional group is selected from one or more of the following: hydroxyl, epoxy, aldehyde, acetal of aldehyde, carboxyl, salt of carboxyl, ester of carboxyl, acid anhydride of carboxyl, boronyl, salt of boronyl, ester of boronyl, silyl, and ester of silyl.

5. The emulsion composition of claim 1 or 2, wherein the surfactant is a nonionic surfactant.

6. The emulsion composition of claim 1 or 2, wherein the content of the surfactant in the emulsion composition is 1 to 15 parts by mass relative to a total of 100 parts by mass of the liquid conjugated diene rubber and the diluent.

7. A method for manufacturing an emulsion composition, which is a method for manufacturing an emulsion composition as claimed in any one of claims 1 to 6, characterized in that the diluent is not removed after mixing the liquid conjugated diene rubber, the diluent, the surfactant, and water to manufacture an oil-water emulsion.