Sealing agent for alkaline batteries and sealing agent composition for alkaline batteries

Abstract

The present invention provides a sealing agent for alkaline batteries, said sealing agent exhibiting excellent adhesion to a metal container and a resin gasket and prolonging the service life of an alkaline battery. This sealing agent contains, as polymer components, at least (A) a non-modified diene non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, and (C) a non-modified diblock polymer; and the proportion of the component (B) in the all polymer components is from 10% by mass to 50% by mass.

Description

[Technical field]

[0001] The present invention relates to a sealing agent for alkaline batteries and a sealing agent composition for alkaline batteries, and in particular to a sealing agent for alkaline batteries that can be suitably used for alkaline primary batteries such as silver oxide batteries, and a sealing agent composition for alkaline batteries using the sealing agent for alkaline batteries. [Background technology]

[0002] 2. Description of the Related Art Alkaline batteries using an alkaline aqueous solution as an electrolyte have been used as power sources for small electronic devices.

[0003] Here, alkaline batteries such as silver oxide batteries are configured by housing a power generating element in a metal container, and a resin gasket and sealing agent made of nylon 66 or the like are used at the opening of the metal container housing the power generating element for insulation and sealing (see, for example, Patent Document 1).

[0004] As a sealant for the opening of an alkaline battery, for example, butadiene rubber, styrene-butadiene rubber, styrene-ethylene-butylene-styrene block copolymer rubber, and block copolymer rubber such as styrene-ethylene-butylene-styrene block copolymer modified with maleic anhydride have been used (see, for example, Patent Document 2). Furthermore, the sealant has been disposed between the metal container and the resin gasket by, for example, applying a sealant composition obtained by dissolving the sealant in a solvent and drying it. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-120549 A [Patent Document 2] Japanese Patent Application Publication No. 11-40118 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the above-mentioned conventional sealing agents for alkaline batteries have room for improvement in terms of increasing the adhesive strength to both the metal container and the resin gasket, as well as preventing leakage of alkaline batteries and realizing a longer battery life.

[0007] Therefore, an object of the present invention is to provide a sealing agent for alkaline batteries and a sealing agent composition for alkaline batteries that can exhibit excellent adhesion to both metal containers and resin gaskets and can extend the life of alkaline batteries. [Means for solving the problem]

[0008] As a result of intensive research, the present inventors have found that by using at least (A) an unmodified diene-based non-block polymer, (B) a hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer as the polymer components of a sealing agent for alkaline batteries, and by adjusting the ratio of (B) the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer to a predetermined ratio in all polymer components, a sealing agent for alkaline batteries can be obtained that can exhibit excellent adhesion to both metal containers and resin gaskets and can extend the life of alkaline batteries, and have completed the present invention.

[0009] That is, the present invention has an object to advantageously solve the above-mentioned problems, and the sealing agent for alkaline batteries of the present invention (hereinafter, also simply referred to as "sealing agent") comprises, as polymer components, at least (A) an unmodified diene-based non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer, and is characterized in that the proportion of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components is 10 mass% or more and 50 mass% or less. In this way, by using at least (A) an unmodified diene-based non-block polymer, (B) a hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer as the polymer components of the sealing agent for alkaline batteries, and by controlling the proportion of the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components to be 10% by mass or more and 50% by mass or less, a sealing agent can be obtained that can exhibit excellent adhesion to both metal containers and resin gaskets, prevent leakage from alkaline batteries, and realize a longer life for the alkaline batteries.

[0010] Here, in the alkaline battery sealing agent of the present invention, the (A) unmodified diene-based non-block polymer is preferably polybutadiene. If polybutadiene is used as the (A) unmodified diene-based non-block polymer, a sealing agent with excellent flexibility can be obtained.

[0011] In the alkaline battery sealing agent of the present invention, the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is preferably an amine-modified styrene-ethylene-butylene-styrene block copolymer. By using an amine-modified styrene-ethylene-butylene-styrene block copolymer as the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B), the adhesive strength to both the metal container and the resin gasket can be improved.

[0012] In the alkaline battery sealant of the present invention, the (C) unmodified diblock polymer preferably has a styrene block. By using the (C) unmodified diblock polymer having a styrene block, it is possible to suppress the generation of large domains when the alkaline battery sealant composition obtained by dissolving the sealant in a solvent is applied and dried to form a thin film.

[0013] Furthermore, in the sealing agent for alkaline batteries of the present invention, the proportion of the unmodified diene-based non-block polymer (A) in the total polymer components is preferably 40% by mass or more and 80% by mass or less. If the proportion of the unmodified diene-based non-block polymer (A) in the total polymer components contained in the sealing agent is within the above range, it is possible to achieve both further improvement in adhesion to both the metal container and the resin gasket and further improvement in flexibility.

[0014] In addition, the sealing agent for alkaline batteries of the present invention preferably contains the unmodified diblock polymer (C) in a proportion of 5% by mass to 20% by mass of the entire polymer components. When the proportion of the unmodified diblock polymer (C) in the entire polymer components contained in the sealing agent is within the above range, the adhesive strength to both the metal container and the resin gasket can be further improved. In the present invention, the proportion of each polymer can be measured by liquid chromatography / mass spectrometry.

[0015] The sealing agent for alkaline batteries of the present invention preferably contains 0.1 to 10 parts by mass of inorganic filler (D) per 100 parts by mass of the solid content of the total polymer components. By containing inorganic filler (D) within the above range, coating unevenness of the layer made of the sealing agent (sealing agent layer) becomes easier to visually recognize when the sealing agent is disposed between a metal container and a resin gasket.

[0016] Furthermore, the sealing agent for alkaline batteries of the present invention preferably contains (E) an unmodified multiblock polymer having 3 or more blocks. By further containing (E) an unmodified multiblock polymer having 3 or more blocks, sufficient adhesion of the sealing agent to both the metal container and the resin gasket can be ensured even when the proportion of (C) the unmodified diblock polymer in the entire polymer component is small.

[0017] In addition, in the sealing agent for alkaline batteries of the present invention, the ratio of the content of the unmodified diene-based non-block polymer (A) to the content of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is preferably from 1 / 7 to 6 by mass. When the ratio of the content of the unmodified diene-based non-block polymer (A) to the content of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is within the above range, the adhesion to a resin gasket and flexibility can be further improved.

[0018] The present invention also aims to advantageously solve the above problems, and the sealing agent composition for alkaline batteries of the present invention (hereinafter also simply referred to as "sealing agent composition") is characterized by containing any one of the above-mentioned sealing agents for alkaline batteries and a solvent. The sealing agent composition for alkaline batteries containing the above-mentioned sealing agent for alkaline batteries and a solvent is resistant to phase separation and therefore has excellent film forming properties. Therefore, by using the sealing agent composition for alkaline batteries of the present invention, a sealing agent layer can be easily formed between a metal container and a resin gasket, and the metal container and the resin gasket can be well adhered to each other. Effect of the Invention

[0019] According to the present invention, it is possible to provide a sealing agent for alkaline batteries that can exhibit excellent adhesion to both metal containers and resin gaskets and can extend the life of alkaline batteries. Furthermore, according to the present invention, it is possible to provide a sealing agent composition for alkaline batteries that can easily form a sealing agent layer that can provide good adhesion between a metal container and a resin gasket. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The alkaline battery sealant and alkaline battery sealant composition of the present invention will be described below. Here, the alkaline battery sealant composition of the present invention contains the alkaline battery sealant of the present invention. The alkaline battery sealant and alkaline battery sealant composition of the present invention can be used when manufacturing an alkaline battery by tightly contacting a metal container of an alkaline battery with a resin gasket to seal the opening of the alkaline battery.

[0021] (Sealant for alkaline batteries) The sealing agent for alkaline batteries of the present invention contains, as polymer components, at least (A) an unmodified diene-based non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer, and may optionally further contain at least one of (D) an inorganic filler, (E) an unmodified multiblock polymer having three or more blocks, and other polymers other than (A) the unmodified diene-based non-block polymer, (B) the hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, (C) the unmodified diblock polymer, and (E) the unmodified multiblock polymer having three or more blocks (hereinafter referred to as "(F) other polymers"), and (G) an additive.

[0022] The alkaline battery sealant of the present invention contains at least (A) an unmodified diene-based non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer as polymer components, and the proportion of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components is 10% by mass or more and 50% by mass or less, so that the sealant can exhibit excellent adhesion to both metal containers and resin gaskets and can realize a long life of an alkaline battery. In addition, since the alkaline battery sealant of the present invention contains the unmodified diblock polymer (C), it is difficult to cause phase separation when dissolved in a solvent to form a sealant composition. The reason why the incorporation of the unmodified diblock polymer (C) makes phase separation difficult is not clear, but it is presumed that the unmodified diblock polymer (C) acts as a compatibilizer for the unmodified diene-based non-diblock polymer (A) and the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B).

[0023] <(A) Unmodified diene-based non-block polymer> Examples of the unmodified diene-based non-block polymer (A) include a homopolymer of one type of diene-based monomer, a random copolymer of two or more types of diene-based monomers, and a random copolymer of a diene-based monomer and a comonomer copolymerizable with the diene-based monomer. These polymers can be used alone or in combination of two or more kinds.

[0024] Here, it is preferable that the unmodified diene-based non-block polymer (A) does not contain a polar group such as an acidic group.

[0025] The diene monomer is not particularly limited, and examples thereof include conjugated diene monomers such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and 4,5-dimethyl-1,3-octadiene. Among these, 1,3-butadiene is preferred as the diene monomer. These diene monomers can be used alone or in combination of two or more kinds.

[0026] The comonomer is not particularly limited, and examples thereof include aromatic vinyl monomers such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene, divinylbenzene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene, 2,4-dimethylstyrene, butoxystyrene, vinylnaphthalene, vinylanthracene, etc. Among them, the comonomer is preferably a monomer having no polar group such as an acidic group, and more preferably styrene. These comonomers may be used alone or in combination of two or more kinds.

[0027] Among these, from the viewpoint of obtaining a sealing agent having excellent flexibility, the unmodified diene-based non-block polymer (A) is preferably a homopolymer of one type of diene-based monomer, and more preferably a homopolymer of 1,3-butadiene (polybutadiene).

[0028] In the total polymer components [(A) unmodified diene-based non-block polymer, (B) hydrogenated product of amine-modified aromatic vinyl-conjugated diene block polymer, (C) unmodified diblock polymer, (E) unmodified multiblock polymer having 3 or more blocks, and (F) other polymers], the proportion of the unmodified diene-based non-block polymer (A) is preferably 40% by mass or more and preferably 80% by mass or less. If the proportion of the unmodified diene-based non-block polymer (A) is equal to or more than the above lower limit, the flexibility of the sealant can be further improved. Also, if the proportion of the unmodified diene-based non-block polymer (A) is equal to or less than the above upper limit, the adhesion of the sealant to the resin gasket can be further increased, and the occurrence of phase separation when the sealant is dissolved in a solvent to prepare a sealant composition can be further suppressed.

[0029] <(B) Hydrogenated product of amine-modified aromatic vinyl-conjugated diene block polymer> In the sealing agent of the present invention, the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is used to increase the polarity of the unmodified diene block polymer (A) described above. According to the sealing agent of the present invention, the combined use of the unmodified diene non-block polymer (A) and the amine-modified aromatic vinyl-conjugated diene block polymer (B) improves the adhesion of the sealing agent to both the metal container and the resin gasket used in the alkaline battery.

[0030] (B) The hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer can be obtained, for example, by performing an addition reaction using a modifier at the living end of an aromatic vinyl-conjugated diene block polymer before amine modification and before hydrogenation to obtain an amine-modified block polymer, and then performing a hydrogenation reaction (hydrogenation reaction).

[0031] Here, examples of the aromatic vinyl-conjugated diene block polymer include styrene-isoprene block copolymers and styrene-butadiene block copolymers. As the aromatic vinyl-conjugated diene block polymer, any of diblock copolymers, terblock copolymers, and mixtures thereof can be preferably used. As the terblock copolymer, styrene-isoprene-styrene block copolymers (SIS) and styrene-butadiene-styrene block copolymers (SBS) can be used. Among these, styrene-isoprene block copolymers (diblock copolymers, terblock copolymers, or mixtures thereof) are preferably used.

[0032] The aromatic vinyl monomer that can be used for preparing the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is not particularly limited, and examples thereof include the above-mentioned aromatic vinyl monomers that can be used for preparing the unmodified diene-based non-block polymer (A), and among these, styrene and α-methylstyrene are preferred. The aromatic vinyl monomers that can be used in preparing the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) can be used alone or in combination of two or more kinds.

[0033] The conjugated diene monomer usable for preparing the hydrogenated product of (B) amine-modified aromatic vinyl-conjugated diene block polymer is not particularly limited, and examples thereof include the above-mentioned conjugated diene monomers usable for preparing the unmodified diene-based non-block polymer of (A), among which 1,3-butadiene and isoprene are preferred. The conjugated diene monomers usable for preparing the hydrogenated product of (B) amine-modified aromatic vinyl-conjugated diene block polymer can be used alone or in combination of two or more kinds.

[0034] Furthermore, the aromatic vinyl-conjugated diene block polymer (B) before the amine modification and before the hydrogenation of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer contains an aromatic vinyl polymer block (P) and a conjugated diene polymer block (Q) and has a block structure of (PQ): n P or (PQ) m (wherein n is an integer of 1 or more, preferably an integer of 1 or more and 10 or less, and m is an integer of 1 or more, preferably an integer of 2 or more and 10 or less).

[0035] The method for producing the aromatic vinyl-conjugated diene block polymer (B) before amine modification and hydrogenation of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer is not particularly limited, and examples thereof include methods using radical polymerization, anionic polymerization, cationic polymerization, coordination anionic polymerization, coordination cationic polymerization, etc. Among these, the method of performing radical polymerization, anionic polymerization, cationic polymerization, etc. by living polymerization, and the method of performing living anionic polymerization are preferred.

[0036] The polymerization is carried out in the presence of a polymerization initiator usually at a temperature ranging from 0° C. to 150° C., preferably from 20° C. to 100° C., and particularly preferably from 10° C. to 80° C. In the case of living anionic polymerization, examples of the polymerization initiator that can be used include monoorganolithium compounds such as n-butyllithium, sec-butyllithium, t-butyllithium, hexyllithium, and phenyllithium; and polyfunctional organolithium compounds such as dilithiomethane, 1,4-dilithiobutane, and 1,4-dilithio-2-ethylcyclohexane.

[0037] The polymerization reaction may be carried out in any form, such as solution polymerization or slurry polymerization, but the use of solution polymerization makes it easy to remove the heat of reaction. In this case, an inert solvent is used in which the polymer obtained in the block polymer production process dissolves. Examples of the inert solvent that can be used include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane, and isooctane; cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, decalin, bicyclo[4.3.0]nonane, and tricyclo[4.3.0.1]cyclohexane. 2,5 ] alicyclic hydrocarbons such as decane; aromatic hydrocarbons such as benzene and toluene. These solvents may be used alone or in combination of two or more. The amount of these solvents used is usually 200 parts by mass or more and 2000 parts by mass or less per 100 parts by mass of the total monomers used.

[0038] When two or more kinds of monomers are used in obtaining a block polymer, a randomizer or the like can be used to prevent only one of the chains from becoming long. In particular, when the polymerization reaction is carried out by anionic polymerization, it is preferable to use a Lewis base compound or the like as a randomizer. Examples of the Lewis base compound include ether compounds such as dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, diphenyl ether, ethylene glycol diethyl ether, and ethylene glycol methylphenyl ether; tertiary amine compounds such as tetramethylethylenediamine, trimethylamine, triethylamine, and pyridine; alkali metal alkoxide compounds such as potassium t-amyl oxide and potassium t-butyl oxide; and phosphine compounds such as triphenylphosphine. These Lewis base compounds may be used alone or in combination of two or more kinds.

[0039] <<Amine modification reaction>> The amine modification reaction can be carried out by adding an amine-containing modifier or a modifier in which the amine is protected by a known method to the living end of the block polymer obtained as described above. This makes it possible to obtain an aromatic vinyl-conjugated diene block polymer (hereinafter sometimes referred to as a "precursor") in which at least one atomic group having at least one amine is bonded. Examples of modifiers having an amine include tetraglycidyl-1,3-bisaminomethylcyclohexane, N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane, etc.

[0040] In addition, when obtaining the precursor, the block polymer may be reacted with an organolithium compound or other organic alkali metal compound (metallation reaction), and the polymer resulting from the addition of the organolithium compound to the block polymer may be subjected to an addition reaction with an amine-containing modifier.

[0041] <<Hydrogenation reaction>> Next, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer is obtained by hydrogenating the precursor obtained as described above. The hydrogenation can be carried out in the presence of a hydrogenation catalyst. Examples of the hydrogenation catalyst include catalysts containing at least one metal selected from nickel, cobalt, iron, titanium, rhodium, palladium, platinum, ruthenium, rhenium, etc., and it is preferable to use a catalyst containing nickel because it prevents scission of the polymer chain and allows hydrogenation at low temperature and low pressure. As the hydrogenation catalyst, either a heterogeneous catalyst or a homogeneous catalyst can be used. In addition, the hydrogenation reaction is preferably carried out in an organic solvent.

[0042] The heterogeneous catalyst can be used as a metal or metal compound, or supported on a suitable carrier. Examples of the carrier include activated carbon, silica, alumina, calcium carbonate, titania, magnesia, zirconia, diatomaceous earth, silicon carbide, and calcium fluoride. The amount of the catalyst supported is usually in the range of 0.1% by mass to 60% by mass, and preferably 1% by mass to 50% by mass. Examples of the supported catalyst include a catalyst having a specific surface area of ​​100 m 2 / g or more 500m 2 / g or less, and the average pore diameter is preferably 100 Å or more and 1000 Å or less, and more preferably 200 Å or more and 500 Å or less. The above-mentioned specific surface area value is a value calculated by measuring the nitrogen adsorption amount and using the BET equation, and the average pore diameter value is a value measured by mercury intrusion porosimetry.

[0043] Examples of homogeneous catalysts include catalysts that combine nickel, cobalt, titanium, or iron compounds with organometallic compounds (e.g., organoaluminum compounds, organolithium compounds); transition metal complex catalysts such as rhodium, palladium, platinum, ruthenium, rhenium, iron, and nickel; and the like. Examples of nickel, cobalt, titanium, or iron compounds include acetylacetonato compounds, carboxylates, and cyclopentadienyl compounds of these metals. Examples of organoaluminum compounds include alkylaluminum such as triethylaluminum and triisobutylaluminum; aluminum halides such as diethylaluminum chloride and ethylaluminum dichloride; and alkylaluminum hydrides such as diisobutylaluminum hydride. Examples of organolithium compounds include lithium boron hydride.

[0044] Examples of the transition metal complex catalyst include transition metal complexes such as dihydrido-tetrakis(triphenylphosphine)ruthenium, dihydrido-tetrakis(triphenylphosphine)iron, bis(cyclooctadiene)nickel, and bis(cyclopentadienyl)nickel.

[0045] These hydrogenation catalysts may be used alone or in combination of two or more. The amount of the hydrogenation catalyst used is usually 0.01 to 100 parts by mass, preferably 0.05 to 50 parts by mass, more preferably 0.1 to 30 parts by mass, based on 100 parts by mass of the polymer.

[0046] The hydrogenation reaction temperature is usually 0°C or higher and 250°C or lower, preferably 50°C or higher and 200°C or lower, and more preferably 80°C or higher and 180°C or lower. When the temperature is within the above range, the hydrogenation rate is high and molecular scission is reduced. Furthermore, when the hydrogen pressure is usually 0.1 MPa or higher and 30 MPa or lower, preferably 1 MPa or higher and 20 MPa or lower, and more preferably 2 MPa or higher and 10 MPa or lower, the hydrogenation rate is high, molecular chain scission is reduced, and operability is also excellent. The hydrogenation rate of the hydrogenation reaction is 1The hydrogenation rate of carbon-carbon unsaturated bonds in the main chain and side chains is preferably 90% or more, more preferably 93% or more, and even more preferably 95% or more, as measured by H-NMR.

[0047] The hydrogenation rate of the carbon-carbon unsaturated bonds in the main chain and side chain of the hydrogenated block polymer is 1 It can be calculated by measuring the H-NMR spectrum and determining the decrease in the integrated value of the signals corresponding to the carbon-carbon unsaturated bonds in the main chain and side chain portions before and after the hydrogenation reaction.

[0048] The hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is obtained from the reaction solution containing the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) after removing the hydrogenation catalyst and / or polymerization catalyst from the reaction solution containing the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) by a method such as filtration or centrifugation.

[0049] Although the above description has been given of a configuration in which the hydrogenation reaction is carried out after the amine modification reaction, the amine modification reaction may be carried out after the hydrogenation reaction of the aromatic vinyl-conjugated diene block polymer. Specifically, for example, the hydrogenated aromatic vinyl-conjugated diene block polymer obtained by the hydrogenation reaction may be subjected to a metalation reaction, and then reacted with an amine-containing modifier to obtain (B) a hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer.

[0050] Specific examples of the hydrogenated product of (B) amine-modified aromatic vinyl-conjugated diene block polymer include a hydrogenated product of amine-modified styrene-butadiene-styrene block copolymer (SBS), i.e., an amine-modified styrene-ethylene-butylene-styrene block copolymer (SEBS); a hydrogenated product of amine-modified styrene-isoprene-styrene block copolymer (SIS), i.e., an amine-modified styrene-ethylene-propylene-styrene block copolymer (SEPS), etc. Among these, from the viewpoint of improving the adhesive strength to both metal containers and resin gaskets, an amine-modified styrene-ethylene-butylene-styrene block copolymer (SEBS) is preferred.

[0051] Incidentally, (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymers are commercially available, and a specific example thereof is Tuftec (registered trademark) MP10 manufactured by Asahi Kasei Chemicals Corporation.

[0052] The proportion of the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components must be 10% by mass or more and 50% by mass or less, preferably 30% by mass or less, and more preferably 20% by mass or less. If the proportion of the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) is within the above range, a sealing agent that can exhibit excellent adhesion to both metal containers and resin gaskets and can realize a long life of alkaline batteries can be obtained. If the proportion of the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components is 30% by mass or less, a sea-island structure is reliably formed in the sealing agent, with the unmodified diene-based non-block polymer (A) as the sea and the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) as the islands, thereby improving the flexibility of the sealing agent.

[0053] In addition, the ratio of the content of the unmodified diene-based non-block polymer (A) to the content of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) [content of unmodified diene-based non-block polymer (A) / content of hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B)] is preferably, by mass, from 1 / 7 to 6. When the ratio of the content of the unmodified diene-based block polymer (A) to the content of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is within the above range, the adhesion to a resin gasket and flexibility can be further improved.

[0054] <(C) Unmodified diblock polymer> In the sealing agent of the present invention, the unmodified diblock polymer (C) is used to uniformly disperse the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) described above. According to the present invention, by using the unmodified diblock polymer (C), the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene polymer (B) can be uniformly dispersed as small domains. This allows the sealing agent of the present invention to exhibit excellent adhesion to both metal containers and resin gaskets, particularly to metal containers and resin gaskets used in alkaline batteries.

[0055] Here, the (C) unmodified diblock polymer is not particularly limited, and any unmodified block polymer having two blocks can be used. Among them, from the viewpoint of suppressing the generation of large domains when a sealant composition obtained by dissolving a sealant in a solvent is applied and dried to form a thin film, the (C) unmodified diblock polymer preferably has a styrene block. Specifically, as the (C) unmodified diblock polymer, it is preferable to use a styrene-based block polymer such as a styrene-butadiene block polymer, a hydrogenated styrene-butadiene block polymer, a styrene-isoprene block polymer, or a hydrogenated styrene-isoprene block polymer. The above-mentioned hydrogenated styrene-butadiene block polymer and hydrogenated styrene-isoprene block polymer may be those in which the intramolecular double bonds are partially hydrogenated or completely hydrogenated.

[0056] In addition, the (C) unmodified diblock polymer preferably does not contain a polar group such as an acidic group.

[0057] The unmodified diblock polymer (C) is commercially available in a mixture with the unmodified triblock polymer described below, for example, as "Kraton G1657" manufactured by Kraton Polymers and "Quintac 3520" manufactured by Zeon Corporation.

[0058] The proportion of the unmodified diblock polymer (C) in the total polymer components is preferably 5% by mass or more and 20% by mass or less. If the proportion of the unmodified diblock polymer (C) in the total polymer components contained in the sealing agent is within the above range, the adhesive strength to both the metal container and the resin gasket can be further improved.

[0059] <(D) Inorganic filler> The (D) inorganic filler that may be optionally contained in the sealing agent of the present invention is not particularly limited, and may be, for example, carbon black, graphite, etc. Specific examples of carbon black include furnace black and channel black, etc. Specific examples of graphite include flake natural graphite and artificial graphite, etc. These (D) inorganic fillers can be used alone or in combination of two or more kinds.

[0060] Furthermore, from the viewpoint of making it easier to visually check uneven application of the sealant layer when the sealant is disposed between a metal container and a resin gasket, it is preferable that the sealant contains 0.1 parts by mass or more and 10 parts by mass or less of (D) inorganic filler per 100 parts by mass of solids of the total polymer components described above.

[0061] <(E) Unmodified multiblock polymer with 3 or more blocks> The non-modified multiblock polymer having 3 or more blocks (E) that may be optionally contained in the sealing agent of the present invention is not particularly limited, but is preferably a non-modified triblock polymer. Note that the non-modified multiblock polymer having 3 or more blocks (E) preferably does not contain a polar group such as an acidic group.

[0062] Here, examples of the (E) unmodified multiblock polymer having 3 or more blocks include a triblock polymer obtained by coupling the above-mentioned (C) unmodified diblock polymer using a coupling agent, and a triblock polymer obtained by adding one arbitrary block to the above-mentioned (C) unmodified diblock polymer. More specifically, examples of the unmodified triblock polymer include styrene-based triblock polymers such as styrene-butadiene-styrene block polymer, hydrogenated styrene-butadiene-styrene block polymer, styrene-ethylene-butylene-styrene block polymer, styrene-isoprene-styrene block polymer, hydrogenated styrene-isoprene-styrene block polymer, and styrene-ethylene-propylene-styrene block polymer.

[0063] <(F) Other polymers> The (F) other polymer that may be optionally contained in the sealing agent of the present invention is not particularly limited, and examples thereof include homopolymers or random copolymers that do not contain diene monomer units (e.g., butyl rubber, ethylene-propylene-diene copolymer rubber, polybutene, etc.).

[0064] <(G) Additives> The additive (G) that may be optionally contained in the sealing agent of the present invention is not particularly limited, and may be, for example, various additives commonly used in the resin industry, such as stabilizers and ultraviolet absorbers.

[0065] Examples of the stabilizer include phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, etc. Among these, phenol-based antioxidants are preferred, and alkyl-substituted phenol-based antioxidants are more preferred. These stabilizers may be used alone or in combination of two or more kinds.

[0066] Examples of the ultraviolet absorber that can be used include organic substances such as benzotriazole-based ultraviolet absorbers, benzoate-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, acrylate-based ultraviolet absorbers, metal complex-based ultraviolet absorbers, and salicylic acid esters, and inorganic substances such as fine particle zinc oxide, cerium oxide, and titanium oxide.

[0067] The amount of the additive (G) to be added is not particularly limited and may be appropriately selected depending on the intended use, but it is generally preferable to keep the amount to 5% by mass or less.

[0068] (Sealing composition for alkaline batteries) The alkaline battery sealant composition of the present invention contains the above-mentioned alkaline battery sealant and a solvent. That is, the alkaline battery sealant composition of the present invention contains (A) an unmodified diene-based non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, (C) an unmodified diblock polymer, and a solvent, and may further contain at least one selected from the group consisting of (D) an inorganic filler, (E) an unmodified multiblock polymer having three or more blocks, (F) other polymers, and (G) an additive.

[0069] <Sealant for alkaline batteries> The alkaline battery sealant of the present invention described above can be used as the alkaline battery sealant. Note that the components blended into the alkaline battery sealant [(A) unmodified diene-based non-block polymer, (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer, (C) unmodified diblock polymer, (D) inorganic filler, (E) unmodified multiblock polymer having 3 or more blocks, (F) other polymers, and (G) additives] are as described above, and therefore will not be described here.

[0070] <Solvent> The solvent used in the sealant composition is a solvent that can dissolve the polymer component in the sealant at room temperature or under heating, and is not limited to a specific solvent.Specific examples of the solvent include organic solvents such as aromatic hydrocarbon compounds such as benzene, toluene, and xylene; saturated aliphatic and alicyclic hydrocarbon compounds such as n-hexane, cyclohexane, methylcyclohexane, ethylcyclohexane, nonane, decane, decalin, tetralin, and dodecane; and hydrocarbon mixtures such as gasoline and industrial gasoline.Of these, xylene and toluene are preferred, and xylene is more preferred.

[0071] <Method of preparing sealant composition> The alkaline battery sealant composition of the present invention can be prepared by mixing (A) an unmodified diene-based non-block polymer, (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, (C) an unmodified diblock polymer, and a solvent with (D) an inorganic filler, (E) an unmodified multiblock polymer having 3 or more blocks, (F) other polymers, and (G) additives as optional components, in any method and order. The mixing method is not particularly limited, and any known mixing method used in the preparation of a sealant composition can be used.

[0072] (Alkaline battery) The sealant and sealant composition of the present invention can be used in alkaline batteries that use an alkaline aqueous solution as an electrolyte. Examples of alkaline batteries include alkaline primary batteries such as silver oxide batteries and alkaline manganese dry batteries, and alkaline secondary batteries such as nickel-cadmium storage batteries, nickel-hydrogen storage batteries, and nickel-zinc storage batteries. Of these, the alkaline battery is preferably an alkaline primary battery, and more preferably a silver oxide battery. The shape of the alkaline battery is not particularly limited, and it may be any shape, such as a button shape, a coin shape, or a cylindrical shape.

[0073] Specifically, an alkaline battery using the sealing agent or sealing agent composition of the present invention includes an alkaline battery comprising a metal container having an opening and housing a power generating element, and a resin gasket attached to the opening of the container via a sealing agent, or a resin gasket attached via a sealing agent to a metal sealing body attached to the opening of the container, in which the sealing agent is a layer (sealing agent layer) made of a sealing agent formed using the sealing agent or sealing agent composition of the present invention.

[0074] Here, the power generating element is not particularly limited, and examples thereof include an electrolyte, a positive electrode, a negative electrode, and a separator. The metal container is not particularly limited, and examples thereof include a container whose inner surface is made of copper. Furthermore, the resin gasket is not particularly limited, and examples thereof include gaskets made of nylon 66. Furthermore, the sealant layer formed using the sealant or sealant composition of the present invention can provide good adhesion between a container whose inner surface is made of copper and a gasket made of nylon 66, and can provide good sealing of the opening.

[0075] Furthermore, the formation of a sealant layer between a resin gasket attached to the opening of a metal container housing a power generating element and the metal container, and / or between the resin gasket and a metal sealing body, can be performed, for example, by the following procedure. First, a predetermined amount of sealant composition is applied to the surface of the container and / or the surface of the gasket by a metering pump such as an air-driven metering dispenser, a roller pump, or a gear pump. After application, the sealant composition is naturally dried while being kept horizontal so as not to be biased, and the solvent is removed to form a thin layer.

[0076] The application of the sealant composition is not limited to the method using a metering pump, and can be done manually with a brush if the amount is small. Furthermore, instead of natural drying, forced drying using a heating device can be used for drying, and in this case, drying can be done in a short time, making it a more suitable process for industrial use.

[0077] When a heating device is used, the solvent is usually removed by drying at about 30 to 150°C for about 5 to 180 minutes. The residual concentration of the solvent in the sealant layer is preferably 5% by mass or less, more preferably 2% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less, by drying and removing the solvent. If the drying temperature of the solvent is equal to or higher than the boiling point of the solvent or close to the boiling point, foaming may occur and unevenness may occur on the surface, so the drying temperature is preferably determined according to the characteristics of the solvent. The drying temperature is determined as a guideline to be a temperature lower than the boiling point of the solvent, preferably 5°C or more, more preferably 10°C or more lower than the boiling point of the solvent. Usually, the sealant composition is dried in the range of 30 to 150°C, taking into account the boiling point of the solvent.

[0078] The thickness of the sealant layer formed by the above method may be selected arbitrarily depending on the size of the container and the gasket, and is usually 0.1 μm or more and 1000 μm or less. By setting the thickness of the sealant layer to the above upper limit or less, the sealant layer can be easily formed. Also, by setting the thickness of the sealant layer to the above lower limit or more, the opening can be well sealed. EXAMPLES

[0079] The present invention will be described below with reference to examples, but the present invention is not limited thereto. In the examples, parts and percentages are by weight unless otherwise specified. In the examples and comparative examples, the coatability, peel strength, electrolyte resistance, and flexibility were measured or evaluated as follows. Moreover, methods for preparing polybutadiene (BR1), polybutadiene (BR2), styrene-isoprene block polymer, and styrene-isoprene-styrene block polymer used in the examples and comparative examples are shown in Polymerization Examples 1 to 4.

[0080] <Applicability> The sealant compositions obtained in the examples and comparative examples were cast onto substrates (a 3 mm-thick nylon 66 plate, a 0.2 mm-thick SUS plate, and a 0.2 mm-thick copper plate) using a doctor blade with a gap of 25 μm, and then heated and dried at 50° C. for 20 minutes to form films (sealant layers) on the substrates. The formed film was visually observed, and when the entire film was colored black, the coatability was evaluated as "good", and when the film was partially transparent, the coatability was evaluated as "poor". Here, when the entire film was colored black, it indicates that the film has an apparent uniformity and that the sealant composition has excellent coatability to the substrate.

[0081] <Peel strength> The sealant compositions obtained in the examples and comparative examples were cast onto substrates (a 3 mm thick nylon 66 plate, a 0.2 mm thick SUS plate, and a 0.2 mm thick copper plate) using a doctor blade with a gap of 250 μm, and then dried by heating at 60° C. for 20 minutes to form a film (sealant layer) on the substrate, and test specimens were obtained. Next, the peel strength of the test piece was measured by the 90° peel method. Specifically, an 18 mm wide adhesive tape was attached to the test piece, and the peel strength was measured using a tensile tester. The higher the peel strength, the better the adhesion to the substrate.

[0082] <Electrolyte resistance> The sealing composition obtained in the examples and comparative examples was cast onto substrates (a nylon 66 plate having a thickness of 3 mm, a SUS plate having a thickness of 0.2 mm, and a copper plate having a thickness of 0.2 mm) using a doctor blade with a gap of 250 μm, and then dried by heating at 60° C. for 20 minutes to form a film on the substrate, and a test specimen was obtained. Next, the test piece was immersed in an electrolyte (30 wt% KOH aqueous solution) (80°C, 100 hours), and the droplets adhering to the surface of the removed test piece were removed. The peel strength of the test piece was then measured by the 90° peel method. Specifically, the peel strength was measured in the same manner as in the above-mentioned <Peel strength>. The higher the peel strength, the better the electrolyte resistance, which can contribute to improving the life of the alkaline secondary battery.

[0083] <Flexibility> The sealing composition obtained in each of the examples and comparative examples was cast onto an aluminum foil having a thickness of 11 μm using a doctor blade with a gap of 250 μm, and then dried by heating at 80° C. for 20 minutes to form a film on the aluminum foil, thereby obtaining a test specimen. The obtained test piece was subjected to a low-temperature bending test. Specifically, the test piece was bent at -30°C with the film-formed surface facing outward, and the bent portion was visually observed. When no cracks, peeling, etc. were observed in the bent portion, the flexibility was evaluated as "good," and when cracks, peeling, etc. were observed, the flexibility was evaluated as "poor."

[0084] <Ratio of the content of (A) unmodified diene non-block polymer to the content of (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer> From the amount of the (A) unmodified diene-based non-block polymer and the amount of the (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer used in the preparation of the sealing composition, the ratio of the content of the (A) unmodified diene-based non-block polymer to the content of the (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer [(A) unmodified diene-based non-block polymer content / (B) hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer content] was calculated. Table 1 shows the ratio rounded to one decimal place.

[0085] <Polymerization Example 1: Preparation of polybutadiene (BR1)> 5000g of toluene and 810g of 1,3-butadiene were added to a 10-liter autoclave equipped with a stirrer, and after thorough stirring, 0.27mol of diethylaluminum chloride and 0.6mmol of chromium chloride-pyridine complex were added, and polymerization was carried out at 60℃ for 3 hours with stirring. Then, 100mL of methanol was added to terminate the polymerization. After the polymerization was terminated, the mixture was cooled to room temperature and the polymerization liquid was removed. The obtained polymerization liquid was solidified with water vapor and then vacuum dried at 60℃ for 48 hours to obtain 780g of solid polybutadiene (BR1). The weight average molecular weight (Mw) of the obtained polybutadiene (BR1) was measured by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent, and was found to be 390,000 in terms of polystyrene.

[0086] <Polymerization Example 2: Preparation of polybutadiene (BR2)> 5000g of toluene and 810g of 1,3-butadiene were added to a 10-liter autoclave equipped with a stirrer, and after thorough stirring, 0.20mol of diethylaluminum chloride and 0.6mmol of chromium chloride-pyridine complex were added, and polymerization was carried out at 60℃ for 3 hours with stirring. Then, 100ml of methanol was added to terminate the polymerization. After the polymerization was terminated, the mixture was cooled to room temperature and the polymerization liquid was removed. The obtained polymerization liquid was solidified with water vapor and then vacuum dried at 60℃ for 48 hours to obtain 760g of solid polybutadiene (BR2). The weight average molecular weight (Mw) of the obtained polybutadiene (BR2) was measured by GPC using THF as a solvent, and was found to be 520,000 in terms of polystyrene.

[0087] <Polymerization Example 3: Preparation of styrene-isoprene block polymer> 5000g of cyclohexane was charged into a 10-liter autoclave equipped with a stirrer, and after heating to 65°C, 0.13g of N,N,N',N'-tetramethylethylenediamine and 1.8g of n-butyllithium were added. Furthermore, 2000g of a cyclohexane solution containing 300g of styrene was added, and polymerization was started with stirring. When the polymerization conversion rate of styrene exceeded 95%, 2000g of a cyclohexane solution containing 1650g of isoprene was added, and polymerization was continued for another 3 hours at 60°C with stirring. Then, 100ml of methanol was added to terminate the polymerization. The obtained polymerization liquid was heated to remove the solvent, and a styrene-isoprene block polymer (hereinafter referred to as "SI block polymer") was obtained. The Mw of the resulting SI block polymer was measured by GPC using THF as a solvent and was found to be 82,000 in terms of polystyrene.

[0088] <Polymerization Example 4: Preparation of styrene-isoprene-styrene block polymer> 5000g of cyclohexane was charged into a 10-liter autoclave equipped with a stirrer, and after heating to 65°C, 0.13g of N,N,N',N'-tetramethylethylenediamine and 1.8g of n-butyllithium were added. Furthermore, 1000g of a cyclohexane solution containing 150g of styrene was added, and polymerization was started while stirring. When the polymerization conversion rate of styrene exceeded 95%, 2000g of a cyclohexane solution containing 1650g of isoprene was added, and polymerization was continued for another 3 hours at 60°C while stirring. Next, 1000g of a cyclohexane solution containing 150g of styrene was added, and polymerization was continued for 3 hours. Then, 100ml of methanol was added to terminate the polymerization. The obtained polymerization liquid was heated to remove the solvent, and a styrene-isoprene-styrene block polymer (hereinafter referred to as "SIS block polymer") was obtained. The Mw of the resulting SIS block polymer was measured by GPC using THF as a solvent and was found to be 85,000 in terms of polystyrene.

[0089] Example 1 (A) 60 parts of polybutadiene (BR1) obtained in Polymerization Example 1 as an unmodified diene-based non-block polymer, (B) 20 parts of an amine-modified styrene-ethylene-butylene-styrene block copolymer [Tuftec (registered trademark) MP10, manufactured by Asahi Kasei Chemicals Corporation (hereinafter referred to as "amine-modified SEBS") as a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer, (C) 20 parts of the SI block polymer obtained in Polymerization Example 3 as an unmodified diblock polymer, (D) 5 parts of carbon black (furnace black having a primary particle size of 10 nm) as an inorganic filler, and xylene as a solvent were mixed and dispersed in a flask equipped with a stirring blade while heating to 50°C, to obtain a uniform solution (sealant composition) with a solid content concentration of 10.5%. Various evaluations were then carried out, and the results are shown in Table 1.

[0090] Example 2 A sealant composition was prepared in the same manner as in Example 1, except that, as the (A) unmodified diene-based non-block polymer, 60 parts of the polybutadiene (BR2) obtained in Polymerization Example 2 was used instead of the polybutadiene (BR1) obtained in Polymerization Example 1, the amount of the SI block polymer as the (C) unmodified diblock polymer was changed to 15 parts, and 5 parts of the SIS block polymer obtained in Polymerization Example 4 was further added as the (E) unmodified multiblock polymer having 3 or more blocks. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0091] Example 3 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as the unmodified diene-based non-block polymer was changed to 75 parts, the blending amount of (B) amine-modified SEBS as the hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer was changed to 15 parts, and the blending amount of (C) SI block polymer as the unmodified diblock polymer was changed to 10 parts. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0092] Example 4 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as an unmodified diene-based non-block polymer was changed to 50 parts, the blending amount of (B) amine-modified SEBS as a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer was changed to 30 parts, the blending amount of (C) SI block polymer as an unmodified diblock polymer was changed to 10 parts, and further, 10 parts of (E) SIS block polymer as an unmodified multiblock polymer having 3 or more blocks was blended. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0093] Example 5 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as the unmodified diene-based non-block polymer was changed to 40 parts, and the blending amount of (B) amine-modified SEBS as the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer was changed to 40 parts. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0094] Comparative Example 1 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as the unmodified diene-based non-block polymer was changed to 90 parts, the blending amount of (B) amine-modified SEBS as the hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer was changed to 5 parts, and the blending amount of (C) SI block polymer as the unmodified diblock polymer was changed to 5 parts. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0095] Comparative Example 2 A sealant composition was prepared in the same manner as in Example 1, except that the amount of polybutadiene (BR1) used as the (A) unmodified diene-based non-block polymer was changed to 100 parts, and that the amine-modified SEBS used as the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) and the SI block polymer used as the unmodified diblock polymer (C) were not used. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0096] Comparative Example 3 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as the unmodified diene-based non-block polymer was changed to 10 parts, the blending amount of (B) amine-modified SEBS as the hydrogenated product of amine-modified aromatic vinyl-conjugated diene block polymer was changed to 80 parts, and the blending amount of (C) SI block polymer as the unmodified diblock polymer was changed to 10 parts. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0097] Comparative Example 4 A sealant composition was prepared in the same manner as in Example 1, except that no SI block polymer was used as the (C) unmodified diblock polymer, and 20 parts of an SIS block polymer was blended as the (E) unmodified multiblock polymer having 3 or more blocks. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0098] Comparative Example 5 A sealant composition was prepared in the same manner as in Example 1, except that no amine-modified SEBS was used as the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B), and 20 parts of an SIS block polymer as the unmodified multiblock polymer having 3 or more blocks (E) was blended. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0099] Comparative Example 6 A sealant composition was prepared in the same manner as in Example 1, except that the blending amount of (A) polybutadiene (BR1) as the unmodified diene-based non-block polymer was changed to 50 parts, (B) amine-modified SEBS as the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer was not used, and (C) the blending amount of the SI block polymer as the unmodified diblock polymer was changed to 50 parts. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0100] Comparative Example 7 A sealant composition was prepared in the same manner as in Example 1, except that the amount of polybutadiene (BR1) used as the (A) unmodified diene-based non-block polymer was changed to 50 parts, (B) the amine-modified SEBS used as the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer, and (C) the SI block polymer used as the unmodified diblock polymer were not used, and 50 parts of a hydrogenated product of a styrene-ethylene-butylene-styrene block copolymer (SEBS) was used as the (F) other polymer. Then, various evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0101] [Table 1]

[0102] From Table 1, it can be seen that the sealing agents (Examples 1 to 5) which contain (A) an unmodified diene-based non-block polymer, (B) a hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer, and (C) an unmodified diblock polymer, and in which the proportion of the hydrogenated amine-modified aromatic vinyl-conjugated diene block polymer (B) in the total polymer components contained in the sealing agent is 10 mass % or more and 50 mass % or less, have excellent adhesion to both copper and nylon 66, and excellent flexibility, and also have excellent electrolyte resistance, and therefore can improve the life of alkaline secondary batteries. Furthermore, from Table 1, it can be seen that the sealing agent in which the proportion of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B), which accounts for the total polymer components of the sealing agent, is 5 mass% (Comparative Example 1), the sealing agent in which it is 80 mass% (Comparative Example 3), and the sealing agent containing only the unmodified diene-based non-block polymer (A) as the polymer component (Comparative Example 2) have poor adhesion to both copper and nylon 66. Furthermore, it is found that the sealants (Comparative Examples 4 to 7) that do not contain at least either (B) the hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer or (C) the unmodified diblock polymer have poor adhesion to both copper and nylon 66, and the coatability of the sealant composition to copper or nylon 66 is poor. [Industrial Applicability]

[0103] According to the present invention, it is possible to provide a sealing agent that can exhibit excellent adhesion to both metal containers and resin gaskets, and can also extend the life of alkaline batteries. Furthermore, according to the present invention, it is possible to provide a sealing agent composition for alkaline batteries that can easily form a sealing agent layer that can provide good adhesion between a metal container and a resin gasket.

Claims

1. As a polymer component, at least (A) an unmodified diene-based non-block polymer; (B) a hydrogenated product of an amine-modified aromatic vinyl-conjugated diene block polymer; (C) an unmodified diblock polymer; Including, Among all polymer components, The proportion of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is 10% by mass or more and 50% by mass or less. Sealant for alkaline batteries.

2. 2. The sealing agent for alkaline batteries according to claim 1, wherein the unmodified diene-based non-block polymer (A) is polybutadiene.

3. 3. The sealing agent for alkaline batteries according to claim 1, wherein the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is an amine-modified styrene-ethylene-butylene-styrene block copolymer.

4. The sealing agent for alkaline batteries according to any one of claims 1 to 3, wherein the unmodified diblock polymer (C) has a styrene block.

5. The sealing agent for alkaline batteries according to any one of claims 1 to 4, wherein the proportion of the unmodified diene-based non-block polymer (A) in the total polymer component is 40 mass% or more and 80 mass% or less.

6. The sealing agent for alkaline batteries according to any one of claims 1 to 5, wherein the proportion of the unmodified diblock polymer (C) in the total polymer component is 5% by mass or more and 20% by mass or less.

7. The sealing agent for alkaline batteries according to any one of claims 1 to 6, comprising (D) 0.1 parts by mass or more and 10 parts by mass or less of an inorganic filler per 100 parts by mass of solid content of the total polymer component.

8. The sealing agent for alkaline batteries according to any one of claims 1 to 7, comprising (E) an unmodified multiblock polymer having 3 or more blocks.

9. The sealing agent for alkaline batteries according to any one of claims 1 to 8, wherein a ratio of a content of the unmodified diene-based non-block polymer (A) to a content of the hydrogenated product of the amine-modified aromatic vinyl-conjugated diene block polymer (B) is 1 / 7 or more and 6 or less on a mass basis.

10. A sealing composition for alkaline batteries, comprising the sealing agent for alkaline batteries according to any one of claims 1 to 9 and a solvent.

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