JP2010274586A - Elastomer laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for preventing oil from oozing out of a styrenic thermoplastic elastomer composition containing oil. <P>SOLUTION: In the elastomer laminate, a photo-curing composition, which contains a photo-curing resin, a (meta) acrylate monomer and a photopolymerization initiator, is coated on the surface of a base material composed of a styrenic thermoplastic elaster composition containing a styrenic elastomer and oil, and then is reacted and cured by having the composition irradiated with energy ray. The photo-curing composition is a hydrogenated conjugated diene polymer or a hydrogenated conjugated diene-aromatic vinyl copolymer having a photo-curable functional group or a mixture of these polymers. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an elastomer laminate that can be used for a sealing material, a gasket material, a vibration damping material, a waterproof material, and the like, and particularly includes a base material made of a styrene-based thermoplastic elastomer composition containing oil. The present invention relates to an elastomer laminate.

  Conventionally, as a low-hardness thermoplastic elastomer composition for a vibration-proof member or a vibration-damping / sound-absorbing member, a composition in which an oil is blended with a styrene-based elastomer is known (see, for example, Patent Document 1 and Patent Document 2). ).

  However, since such a styrenic thermoplastic elastomer composition contains oil as a softening agent, it can achieve low hardness, but the oil oozes to the surface when a load is applied, that is, oil There was a problem that bleeding occurred.

JP 2003-105311 A JP 2006-225581 A

  Therefore, establishment of means capable of preventing oil from oozing out from the above-described styrenic thermoplastic elastomer composition when a load is applied has been demanded.

  An object of the present invention is to advantageously solve the above-mentioned problems, and an elastomer laminate according to the present invention is a surface of a substrate comprising a styrene-based thermoplastic elastomer composition containing a styrene-based elastomer and oil. After applying a photocurable composition containing a photocurable resin, a (meth) acrylate monomer, and a photopolymerization initiator, the photocurable composition is irradiated with energy rays to cause reaction curing. The photocurable resin is a hydrogenated conjugated diene polymer, a hydrogenated conjugated diene-aromatic vinyl copolymer containing a photocurable functional group, or a mixture thereof. It is characterized by. Thus, if the surface of a substrate made of a styrene-based thermoplastic elastomer composition is coated with a photocurable composition and the photocurable composition is cured by reaction to form an elastomer laminate, the elastomer laminate Even when a load is applied, the base material made of the styrenic thermoplastic elastomer composition is coated with the cured photocurable composition, so that the oil does not ooze out. In addition, a hydrogenated conjugated diene polymer, a hydrogenated conjugated diene-aromatic vinyl copolymer, or a mixture thereof is used as a photocurable resin, and a (meth) acrylate monomer is added to the photocurable composition. Therefore, the photocurable composition cured by irradiation with energy rays and the base material adhere well. (Meth) acrylate refers to acrylate or methacrylate.

  Here, in the elastomer laminate of the present invention, the ester residue of the (meth) acrylate monomer is an alkyl group having 12 to 18 carbon atoms, an isobornyl group, a dicyclopentanyl group, a cyclohexyl group, or a dicyclopentenyl group. It is preferable. This is because if such a (meth) acrylate monomer having an ester residue is added to the photocurable composition, the adhesiveness between the photocurable composition cured by irradiation with energy rays and the substrate is improved. In addition, the ester residue of a (meth) acrylate monomer means the residue remove | excluding one hydroxyl group of the hydroxyl-containing compound among the (meth) acrylic acid and hydroxyl-containing compound which comprise a (meth) acrylate monomer.

  Moreover, the elastomer laminated body of this invention contains the said (meth) acrylate monomer in the ratio of 1-150 mass parts, when all the photocurable resins are 100 mass parts. Is more preferable, and it is more preferable to include in the ratio of 20-70 mass parts, and it is still more preferable to include in the ratio of 30-60 mass parts. If the blending amount of the (meth) acrylate monomer is too small, the adhesiveness between the photocurable composition cured by irradiation with energy rays and the base material is lowered, and the blending amount of the (meth) acrylate monomer is too large. This is because the hardness of the elastomer laminate is increased.

  According to the elastomer laminate of the present invention, since the substrate made of the styrene-based thermoplastic elastomer composition is coated with the cured photocurable composition, the substrate (when the load is applied to the elastomer laminate) It is possible to prevent oil from oozing out from the styrene-based thermoplastic elastomer composition).

  Hereinafter, the elastomer laminate of the present invention will be described in detail. The elastomer laminate of the present invention comprises a photocurable resin, a (meth) acrylate monomer, and a photopolymerization initiator on the surface of a substrate made of a styrene thermoplastic elastomer composition containing a styrene elastomer and oil. The photocurable composition is reacted and cured after being coated with a photocurable composition containing.

(Styrenic thermoplastic elastomer composition)
As the styrene-based thermoplastic elastomer composition used for the base material of the elastomer laminate of the present invention, a known elastomer composition containing a styrene-based elastomer and oil can be used.

  Here, as the styrene-based thermoplastic elastomer composition, for example, an elastomer composition described in JP 2000-169666 A or JP 2002-225303 A can be used.

  Specifically, without limitation, hydrogen is added to a block copolymer comprising at least one polymer block mainly composed of a vinyl aromatic compound and at least one polymer block mainly composed of a conjugated diene compound. An elastomer composition containing a hydrogenated block copolymer (styrene elastomer) obtained by addition and a non-aromatic rubber softener (oil) can be used. This elastomer composition may further contain a polyolefin-based hydrocarbon resin.

  Here, as the hydrogenated block copolymer, for example, a block copolymer of polybutadiene and polystyrene, a block copolymer of polyisoprene and polystyrene, or a polybutadiene or ethylene-butadiene random copolymer and polystyrene are used. Diblock copolymer of crystalline polyethylene and polystyrene, styrene-ethylene / butylene-styrene triblock copolymer (SEBS), styrene-ethylene / propylene-styrene, obtained by hydrogenating a block copolymer of In addition to triblock copolymerization (SEPS), a block copolymer having at least two polymer blocks mainly composed of vinyl aromatic compounds and at least one polymer block mainly composed of conjugated diene compounds ( For example, styrene-butadiene-s Ren block copolymer, styrene - isoprene - styrene block copolymer, etc.) may be mentioned hydrogenated block copolymer obtained by hydrogenating.

  The non-aromatic rubber softening agent is for lowering the hardness of the thermoplastic elastomer, and as such a softening agent, a liquid or liquid at room temperature is usually suitably used. And as non-aromatic rubber softeners, mineral oil softeners such as naphthenic process oil and paraffinic process oil, castor oil, cottonseed oil, rapeseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, Examples include vegetable oil-based softeners such as peanut oil, wax, pine oil and olive oil, and synthetic softeners such as polyisobutylene oil. In addition, these softeners may be used individually by 1 type, and may mix and use 2 or more types if mutual compatibility is favorable.

  Here, the blending amount of these softeners is usually 1 to 3000 parts by weight, preferably 50 to 1000 parts by weight, particularly preferably 100 to 300 parts by weight with respect to 100 parts by weight of the hydrogenated block copolymer. .

  In addition, a polyolefin-based hydrocarbon resin mainly composed of polypropylene can be added to the above-described styrene-based thermoplastic elastomer composition in order to improve the processability and heat resistance characteristics of the composition. Examples of the resin include isotactic polypropylene, a copolymer of propylene and a small amount of other α-olefin (for example, propylene-ethylene copolymer, propylene / 4-methyl-1-pentene copolymer), and the like. Can be mentioned. Here, the compounding quantity of polyolefin-type hydrocarbon resin is 0-50 mass parts with respect to 100 mass parts of hydrogenated block copolymers, Preferably it is 0-30 mass parts, Most preferably, it is 5-20 mass parts.

  In addition, in order to improve workability and heat resistance, a polystyrene resin may be added to the styrene thermoplastic elastomer composition in addition to the polyolefin hydrocarbon resin. Moreover, you may mix | blend a known additive.

  And the above-mentioned styrenic thermoplastic elastomer composition is obtained by mixing the above-mentioned hydrogenated block copolymer with a known kneading means such as a single screw extruder, a twin screw extruder, a roll, a Banbury mixer, a Brabender, a kneader, It can be produced by kneading using a high shear mixer or the like.

(Photocurable composition)
As the photocurable composition used for the elastomer laminate of the present invention, a known photocurable composition containing a photocurable resin, a (meth) acrylate monomer, and a photopolymerization initiator can be used.

  Here, as the photocurable composition, for example, a photocurable composition as described in JP-A-2007-145949 can be used.

  Specifically, a photocurable composition containing a photocurable resin produced by the following method, a (meth) acrylate monomer, and a photopolymerization initiator can be used without any limitation.

<Photocurable resin>
The photocurable resin used in the photocurable composition is a hydrogenated conjugated diene polymer (for example, hydrogenated butadiene polymer) or a hydrogenated conjugated diene-aromatic vinyl copolymer (for example, water) containing a photocurable functional group. Styrene-butadiene copolymer) or a mixture of a hydrogenated conjugated diene polymer and a hydrogenated conjugated diene-aromatic vinyl copolymer, which can be produced, for example, as follows.
(1) First, a butadiene monomer (for example, 1,3-butadiene) or a butadiene monomer and a styrene monomer are polymerized with a dilithium initiator in a saturated hydrocarbon solvent to obtain a butadiene polymer. Alternatively, a styrene-butadiene copolymer (hereinafter, simply referred to as “(co) polymer”) is produced. Here, since the main polymerization is living anionic polymerization, the polymerization can be performed while controlling the molecular weight and molecular weight distribution. It is possible to polymerize a polymer having a predetermined molecular weight depending on the amount of the dilithium initiator and the above monomer. Particularly when the weight average molecular weight is 5000 or more, a narrow polymer having a molecular weight distribution of 2 or less is easily obtained. If desired, anionic polymerization may be carried out in the presence of a randomizer. The (co) polymer refers to “polymer or copolymer”.
(2) Next, a butadiene polymer polyol or styrene having a hydroxyl group at both ends by reacting the polymer end which is the living anion of the (co) polymer produced in (1) above with an alkylene oxide. A butadiene copolymer polyol (hereinafter, simply referred to as “(co) polymer polyol”) can be obtained.
(3) Further, the (co) polymer polyol having a double bond in the main chain produced in (2) above is subjected to a hydrogenation reaction (hereinafter referred to as “hydrogenation reaction”), so A hydrogenated butadiene polymer polyol or a hydrogenated styrene butadiene copolymer polyol having no saturated double bond (hereinafter sometimes simply referred to as “hydrogenated (co) polymer polyol”) can be obtained.
(4) Finally, by reacting the hydrogenated (co) polymer polyol obtained as described above with a photocurable unsaturated hydrocarbon group-containing compound as a photocurable functional group-containing compound, A liquid photocurable resin into which a photocurable functional group (photocurable unsaturated hydrocarbon group) is introduced is obtained.

  The dilithium initiator is not particularly limited, and known ones can be used. Specifically, for example, a dilithium initiator produced by reacting a monolithium compound with a disubstituted vinyl or an alkenyl group-containing aromatic hydrocarbon in the presence of a tertiary amine can be used.

  Here, as a monolithium compound used when manufacturing a dilithium initiator, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, tert-octyl lithium, Examples include n-decyl lithium, phenyl lithium, 2-naphthyl lithium, 2-butyl-phenyl lithium, 4-phenyl-butyl lithium, cyclohexyl lithium, cyclopentyl lithium, and among these, sec-butyl lithium is particularly preferable.

  Examples of the tertiary amine used when producing the dilithium initiator include lower aliphatic amines such as trimethylamine and triethylamine, and N, N-diphenylmethylamine. Triethylamine is particularly preferable. Examples of the disubstituted vinyl or alkenyl group-containing aromatic hydrocarbon include 1,3- (diisopropenyl) benzene, 1,4- (diisopropenyl) benzene, 1,3-bis (1-ethylethenyl). ) Benzene, 1,4-bis (1-ethylethenyl) benzene and the like.

  The solvent used in the preparation of the dilithium initiator and the production of the (co) polymer may be an organic solvent inert to the reaction. Examples of the solvent include aliphatic, alicyclic, and aromatic hydrocarbon compounds. Hydrocarbon solvents can be used. Specifically, for example, n-butane, l-butane, n-pentane, l-pentane, cis-2-butene, trans-2-butene, l-butene, n-hexane, n-heptane, n-octane , L-octane, methylcyclopentane, cyclopentane, cyclohexane, 1-hexene, 2-hexene, 1-pentene, 2-pentene, benzene, toluene, xylene, ethylbenzene and the like. Of these, n-hexane and cyclohexane are usually used.

  Moreover, as alkylene oxide used for the polyolation reaction which reacts with the terminal which is a living anion of said (co) polymer, and produces | generates a hydroxyl group at both ends, it is possible to use ethylene oxide, propylene oxide, butylene oxide, etc., for example. it can. This polyol reaction is preferably performed immediately after the polymerization reaction.

  In addition, when the weight average molecular weight of the (co) polymer polyol obtained by the above-mentioned polyolation reaction is 5000 or more, the above-described photocurable resin can increase the molecular weight between cross-linking points, and after the photocuring reaction. The elastic modulus of the photocurable resin can be lowered and the elongation can be increased. On the other hand, when the molecular weight is 40,000 or less, the polymerization viscosity does not become too high when polymerization is carried out with a dilithium catalyst, and it is not necessary to lower the solid content concentration as a polymerization process, so that it can be produced at low cost.

  Moreover, various influences by a low molecular weight component and a high molecular weight component can be suppressed as molecular weight distribution is 3.0 or less. In particular, since the viscosity is greatly affected by the molecular weight, slight fluctuations in the molecular weight cause viscosity variations. Since it can synthesize | combine the (co) polymer of narrow molecular weight distribution if it manufactures according to said (1)-(4), the (co) polymer of the same molecular weight can be obtained with sufficient reproducibility. Therefore, the viscosity can be stabilized. Usually, a liquid material such as the above-described photo-curable resin is often dispensed by a dispenser. In this case, variation in material viscosity causes variation in dimensions after application, and thus stabilization of the viscosity is important. . Accordingly, the photocurable resin preferably has a molecular weight distribution of 3.0 or less.

The hydrogenation reaction is performed by hydrogenating the (co) polymer polyol in an organic solvent under hydrogen pressure and in the presence of a hydrogenation catalyst. As a hydrogenation catalyst, palladium-carbon, reduced nickel, rhodium-based heterogeneous catalyst, or organic nickel compounds such as nickel naphthenate and nickel octoate, or organic cobalt compounds such as cobalt naphthenate and cobalt octoate A homogeneous catalyst in which an organic aluminum compound such as triethylaluminum or triisobutylaluminum or an organic lithium compound such as n-butyllithium or sec-butyllithium is combined can be used. As a cocatalyst, ether compounds such as tetrahydrofuran, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether may be used. Further, as another hydrogenation reaction method, for example, the (co) polymer before hydrogenation may be dicyclopentadienyl titanium halide, organic carboxylate nickel, organic carboxylate nickel, and groups I to III of the periodic table. The catalyst is a hydrogenation catalyst comprising any of the above organometallic compounds, nickel, platinum, barium, ruthenium, rhenium, rhodium metal catalyst or cobalt, nickel, rhodium, ruthenium complex, etc. supported on carbon, silica, diatomaceous earth, etc. Under hydrogen pressurized to -100 atm, or in the presence of lithium aluminum hydride, p-toluenesulfonyl hydrazide, Zr-Ti-Fe-V-Cr alloy, Zr-Ti-Nb-Fe-V-Cr alloy, LaNi ₅ presence of hydrogen storage alloy such as alloy, or hydrogenated in the pressurized under hydrogen in 1-100 atm Or a hydrogenation catalyst obtained by mixing di-p-tolyl-bis (1-cyclopentadienyl) titanium / cyclohexane solution and n-butyllithium / n-hexane solution under hydrogen Examples thereof include a method of adding hydrogen under hydrogen pressurized to 100 atm.

  Of the various hydrogenation catalysts described above, a Ziegler hydrogenation catalyst or palladium-carbon hydrogenation catalyst comprising a combination of a transition metal compound and an alkylaluminum compound is preferred. Here, as the transition metal compound, tris (acetylacetonato) cobalt, bis (acetylacetonato) nickel, tris (acetylacetonato) iron, tris (acetylacetonato) chromium, tris (acetylacetonato) manganese, bis (Acetylacetonato) manganese, tris (acetylacetonato) ruthenium, bis (acetylacetonato) cobalt, bis (cyclopentadienyl) dichlorotitanium, bis (cyclopentadienyl) dichlorozirconium, bis (triphenylphosphine) cobalt Examples include dichloride, bis (2-hexanoate) nickel, bis (2-hexanoate) cobalt, titanium tetraisopropoxide, and titanium tetraethoxide. Among these, bis (acetylacetonato) nickel and tris (acetylacetonato) cobalt are preferable from the viewpoint of high hydrogenation activity. Alkyl aluminum compounds used for Ziegler hydrogenation catalysts include trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-n-butylaluminum, dimethylaluminum chloride, diethylaluminum chloride, diisobutylaluminum chloride, methylaluminum. Examples thereof include dichloride, ethylaluminum dichloride, isobutylaluminum dichloride, diethylaluminum hydride, diisobutylaluminum hydride, and ethylaluminum sesquichloride. Among these, from the viewpoint of hydrogenation activity, triisobutylaluminum, triethylaluminum, and diisobutylaluminum hydride are preferable, and triisobutylaluminum is most preferable.

  In addition, although there is no restriction | limiting in particular in the usage form of a Ziegler type | system | group hydrogenation catalyst, The method of preparing the catalyst solution which made the transition metal compound and the alkylaluminum compound react previously and adding it to the polymerization solution can be mentioned. The amount of the alkylaluminum compound used at this time is preferably 0.2 to 5 mol with respect to 1 mol of the transition metal compound. The catalyst preparation reaction is carried out in the temperature range of −40 to 100 ° C., preferably 0 to 80 ° C., and the reaction time is in the range of 1 minute to 3 hours.

  The hydrogenation reaction is usually at a temperature of 50 to 180 ° C., preferably 70 to 150 ° C., and 5 to 100 atm (5066.25 to 101325 hPa), preferably 10 to 50 atm (10132.5 to 50662.5 hPa). ) Hydrogen pressure. If the hydrogenation temperature is lower than 50 ° C., or if the hydrogen pressure is lower than 5 atm, the catalyst activity is low, which is not preferable. If the hydrogenation temperature exceeds 180 ° C., catalyst deactivation, side reactions, etc. are likely to occur. It is not preferable. In general, a Ziegler-based hydrogenation catalyst is a catalyst having extremely high hydrogenation activity, and it is not preferable to set the hydrogen pressure to 100 atm (101325 hPa) or more because it is not necessary and a burden on the apparatus is increased.

  The hydrogenated (co) polymer polyol is reacted with a photocurable unsaturated hydrocarbon group-containing compound as a photocurable functional group-containing compound, and photocured at the terminal of the hydrogenated (co) polymer polyol. In order to introduce a functional functional group (photocurable unsaturated hydrocarbon group), the photocurable unsaturated hydrocarbon group is preferably an acryloyl group or a methacryloyl group. Here, as the photocurable unsaturated hydrocarbon group-containing compound, acryloyloxyalkyl isocyanate and methacryloyloxyalkyl isocyanate are preferable, and the above hydrogenated (co) polymer polyol is (meth) acrylate by reaction with them. It becomes. Here, examples of the acryloyloxyisocyanate include 2-acryloyloxyethyl isocyanate, and examples of the methacryloyloxyisocyanate include 2-methacryloyloxyethyl isocyanate.

<(Meth) acrylate monomer>
The (meth) acrylate monomer used in the photocurable composition reduces the viscosity of the photocurable composition before curing and improves various physical properties after curing. That is, by blending a (meth) acrylate monomer, it is possible to improve the adhesive strength of the photocurable composition, decrease the hardness, improve Eb (elongation) and Tb (breaking strength), and the like. As this (meth) acrylate monomer, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, isostearyl (meth) acrylate, isomyristyl (meth) acrylate, lauryl (meth) Acrylate, dicyclopentanyloxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolypropylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol-polypropylene glycol (meth) ) Acrylate, nonylphenoxy polypropylene glycol-polyethylene glycol (meth) acrylate, etc.

  Here, the blending amount of the (meth) acrylate monomer is preferably 1 to 150 parts by weight, more preferably 20 to 70 parts by weight, and more preferably 30 to 60 parts by weight with respect to 100 parts by weight of the photocurable resin. More preferably, it is part. If the blending amount of the (meth) acrylate monomer is too small, the adhesiveness between the photocurable composition cured by irradiation with energy rays and the base material is lowered, and the blending amount of the (meth) acrylate monomer is too large. This is because the hardness of the elastomer laminate is increased.

<Photopolymerization initiator>
Examples of the photopolymerization initiator used in the photocurable composition include aminoacetophenones, benzoin derivatives, benzyl ketals, hydroxyacetophenones, aminoacetophenones and thioxanthones (for example, isopropylthioxanthone, diethylthioxanthone). ), And acylphosphine oxides. Examples of the hydrogen abstraction type include a mixture of benzophenones and amine, a mixture of thioxanthone and amine, and the like. As the photopolymerization initiator, the above-described intramolecular cleavage type and hydrogen abstraction type may be used in combination.

  Here, aminoacetophenones are particularly preferred as the photopolymerization initiator. Aminoacetophenones have high reaction activity as photopolymerization initiators and are less susceptible to oxygen inhibition of the surface of the photocurable composition due to the presence of nitrogen atoms, so that the curability of the entire photocurable composition is improved and cured. This is because the tackiness (tackiness) and compression set of the subsequent photocurable composition can be reduced. As aminoacetophenones, 2-methyl-1-[(4-methylthio) phenyl] -2-morpholinopropan-1-one [manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 907], 2 -Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone [Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 369], 2- (dimethylamino) -2-[(4 -Methylphenyl) methyl] -1- (4-morpholinophenyl) -1-butanone [Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 379] and the like. Aminoacetophenones may be used alone or in combination with other photopolymerization initiators.

  Examples of the benzoin derivatives described above include benzoin, benzoin alkyl ether (alkyl having 1 to 6 carbon atoms), specifically, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like. it can. Further, examples of benzyl ketals include 2,2-dimethoxy-1,2-diphenylethane-1-one [manufactured by Ciba Specialty Chemicals, Inc., trade name: Irgacure 651]. Are 2-hydroxy-2-methyl-1-phenyl-propan-1-one [Ciba Specialty Chemicals Co., Ltd., trade name: Darocur 1173], 1-hydroxy-cyclohexyl-phenylketone [Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 184], 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propane- 1-on [Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 127] It is. Examples of the acylphosphine oxides include bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide [manufactured by Ciba Specialty Chemicals, Inc., trade name: Irgacure 819].

  In addition to the above-mentioned photopolymerization initiator, oligomerized α-hydroxyacetophenone, for example, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone] [ Lamberti S. p. A product, trade name: ESACURE KIP150, etc.] and acrylated benzophenones such as acrylated benzophenone [e.g., trade name: Ebecryl P136, etc., manufactured by Daicel UCB Co., Ltd.] can be used. . Also, benzoyl methyl ether, benzoyl ethyl ether, benzoyl butyl ether, benzoyl isopropyl ether, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl ] Propanol oligomer, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer and 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone, o- Methyl benzoylbenzoate, [4- (methylphenylthio) phenyl] phenylmethane, imide acrylate, and the like can also be used.

  Here, it is preferable that the compounding quantity of a photoinitiator is 0.1-6 mass parts with respect to a total of 100 mass parts of photocurable resin and a (meth) acrylate monomer, 0.5-5 mass parts It is more preferable that it is 1-4 mass parts.

(Other additives)
Moreover, you may mix | blend normally used additives, such as a thixotropic agent and a stabilizer, with the photocurable composition used for this invention arbitrarily.

  Here, the thixotropic agent imparts thixotropic properties to the photocurable composition to improve the processability of the photocurable composition, and as a thixotropic agent to be blended in the photocurable composition. There are organic thixotropic agents and inorganic thixotropic agents.

  Specifically, as the organic thixotropic agent, hydrogenated castor oil type, amide type, polyethylene oxide type, vegetable oil polymerized oil type, surfactant type thixotropic agent, or a thixotropic combination of two or more of these. Agents. Here, the hydrogenated castor oil-based thixotropic agent is obtained by adding hydrogen to castor oil (non-drying oil whose main component is ricinoleic acid) and curing it into a wax form [for example, trade name, manufactured by Zude Chemie Catalysts, Inc. : ADVITROL100, manufactured by Enomoto Kasei Co., Ltd., trade name: Disparon 305, etc.], and the amide thixotropic agent is an amide wax [for example, Enomoto Kasei (for example, a compound having an amide bond synthesized from vegetable oil fatty acid and amine) Product name: Disparon 6500, etc.].

  Examples of the inorganic thixotropic agent include silica, bentonite, organic coupling agent-treated silica, organic coupling agent-treated bentonite, ultrafine surface-treated calcium carbonate, or a mixture thereof. Specifically, as an inorganic thixotropic agent, silica fine powder pulverized by a dry method [for example, product name: Aerosil 300 manufactured by Nippon Aerosil Co., Ltd.], this silica fine powder is modified with trimethyldisilazane. Fine powder [for example, manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil RX300, etc.] and fine powder obtained by modifying the above silica fine powder with polydimethylsiloxane [for example, manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil RY300, etc. ] Etc. are mentioned. Here, the average particle diameter of the inorganic thixotropic agent described above is preferably 5 to 50 μm and more preferably 5 to 12 μm from the viewpoint of imparting thixotropy.

  In addition, it is preferable that the compounding quantity of a thixotropic agent is 0.1-10 mass parts with respect to a total of 100 mass parts of photocurable resin and a (meth) acrylate monomer, and is 0.5-8 mass parts. It is more preferable, and it is still more preferable that it is 1-5 mass parts.

  Moreover, as a stabilizer added to the photocurable composition described above, triethylene glycol bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate] [Ciba Specialty Chemicals ( Product name: IRGANOX245, manufactured by Asahi Denka Kogyo Co., Ltd., product name: ADK STAB AO-70, etc.], 3,9-bis {2- [3- (3-t-butyl-4-hydroxy-5) -Methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5] undecane [Asahi Denka Kogyo Co., Ltd., trade name: ADK STAB AO-80, etc. And the like, and the like.

  Here, it is preferable that the compounding quantity of a stabilizer is 0.1-5 mass parts with respect to a total of 100 mass parts of photocurable resin and a (meth) acrylate monomer, and is 0.5-3 mass parts. More preferably, it is more preferably 0.5 to 2 parts by mass.

  Furthermore, in the above-mentioned photocurable composition, various tackifiers such as terpene resin, terpene phenol resin, coumarone resin, coumarone-indene resin, petroleum hydrocarbon, rosin derivative, etc. for improving adhesion, A colorant such as titanium black can also be added.

  Moreover, in addition to the said (meth) acrylate monomer, a terminal (meth) acrylate oligomer can be mix | blended with a photocurable composition. By blending this terminal (meth) acrylate oligomer, the viscosity of the photocurable composition can be adjusted. Physically, the hardness decreases, and Eb (elongation) and Tb (breaking strength). The improvement etc. can be aimed at. The terminal (meth) acrylate oligomer refers to an oligomer having an acryloyl group or a methacryloyl group at one end or both ends.

  Here, examples of the terminal (meth) acrylate oligomer include polyester (meth) acrylate oligomers, epoxy (meth) acrylate oligomers, urethane (meth) acrylate oligomers, polyol (meth) acrylate oligomers, and the like. The polyester (meth) acrylate oligomer is obtained by, for example, esterifying the hydroxyl group of a polyester oligomer having a hydroxyl group at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, Or it can obtain by esterifying the hydroxyl group of the terminal of the oligomer obtained by adding an alkylene oxide to polyhydric carboxylic acid with (meth) acrylic acid. The epoxy (meth) acrylate-based oligomer can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or a novolak type epoxy resin and esterifying it. The polyol (meth) acrylate oligomer can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid. The urethane (meth) acrylate oligomer can be obtained, for example, by esterifying a polyurethane oligomer obtained by a reaction between a polyether polyol or a polyester polyol and a polyisocyanate with (meth) acrylic acid.

<Manufacture of a photocurable composition>
The manufacturing method of the photocurable composition mentioned above is not specifically limited, A well-known method is applicable. For example, the components described above can be produced by kneading using a temperature-adjustable kneader such as a single screw extruder, twin screw extruder, planetary mixer, twin screw mixer, high shear mixer, etc. it can.

(Elastomer laminate)
The elastomer laminate of the present invention is formed by applying the photocurable composition obtained as described above to the surface of a base material composed of the above styrenic thermoplastic elastomer composition to form an application layer, It can be produced by reacting and curing the coating layer by irradiation.

  Here, the shape of the substrate can be an arbitrary shape depending on the use of the elastomer laminate, such as a sheet shape, a columnar shape, a prismatic shape, or a block shape.

  Moreover, the application of the photocurable composition to the substrate (adhered body) can be performed by any method after adjusting the temperature of the composition as necessary to obtain a constant viscosity. For example, gravure coating, roll coating, spin coating, reverse coating, bar coating, screen coating, blade coating, air knife coating, dipping, dispensing, inkjet, and the like.

  Here, the energy rays used to react and cure the photocurable composition indicate ultraviolet rays and ionizing radiation such as electron rays, α rays, β rays, γ rays, etc. In the present invention, ultraviolet rays are used. It is preferable to use it. Examples of the ultraviolet light source include a xenon lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, and a microwave excimer lamp. The atmosphere for irradiation with ultraviolet rays is preferably an inert gas atmosphere such as nitrogen gas or carbon dioxide gas, or an atmosphere with a reduced oxygen concentration, but can be sufficiently cured even in a normal air atmosphere. The irradiation atmosphere temperature can usually be 10 to 200 ° C.

  The photo-curable resin can be stabilized by irradiating energy rays again after curing, or by applying heat.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

(Production of styrenic thermoplastic elastomer composition)
Styrenic elastomer (made by Kuraray, Septon), polyolefin resin (PP), and oil (made by Idemitsu Kosan Co., Ltd., paraffinic oil: Diana Process PW380) are weighed and kneaded with a Brabender or a twin screw extruder, and pellets Was prepared. Thereafter, the prepared pellets were formed into a 1 to 2 mm sheet using an injection molding machine at a temperature of 180 to 220 ° C.

(Manufacture of photocurable resin)
[Manufacture of hydrogenated SBR]
First, 1 mol of 1,3- (diisopropenyl) benzene is added to a fully dehydrated and purified cyclohexane solvent, 2 mol of triethylamine and 2 mol of sec-butyllithium are sequentially added, and the mixture is stirred at 50 ° C. for 2 hours. Thus, a dilithium polymerization initiator was prepared.
Next, in a 7 liter polymerization reactor purged with argon, 1.90 kg of dehydrated and purified cyclohexane, 2.00 kg of a hexane solution of 22.9% by mass of 1,3-butadiene monomer, 20.0% by mass of styrene monomer A cyclohexane solution of 0.765 kg and a 1.6 mol / liter 2,2-di (tetrahydrofuryl) propane hexane solution (130.4 ml) were added, followed by a 0.5 mol / liter dilithium polymerization initiator. Polymerization was initiated by adding 0 ml.
Then, polymerization was carried out for 1.5 hours while raising the temperature of the polymerization reactor to 50 ° C., 108.0 ml of a 1 mol / liter ethylene oxide cyclohexane solution was added, and the mixture was further stirred for 2 hours, and then 50 ml of isopropyl alcohol. Was added. A hexane solution of the copolymer was precipitated in isopropyl alcohol and sufficiently dried to obtain a copolymer polyol. This copolymer polyol was a styrene-butadiene copolymer having OH groups at both ends, the styrene content was 25% by mass, the weight average molecular weight was 14,500, and the molecular weight distribution was 1.20. In addition, the weight average molecular weight and molecular weight distribution were calculated | required in polystyrene conversion using GPC method.

Next, 120 g of the above-described copolymer polyol was dissolved in 1 liter of sufficiently dehydrated and purified hexane, and then prepared in a separate container in advance. Nickel naphthenate, triethylaluminum, and butadiene were 1: 3: 3 (molar ratio). The catalyst solution was charged so that the amount of nickel was 1 mole per 1000 moles of the butadiene portion in the copolymer solution. Hydrogen was pressurized to 27580 hPa (400 psi) in a sealed reaction vessel, and a hydrogenation reaction was performed at 110 ° C. for 4 hours. Thereafter, the catalyst residue was extracted and separated with 3N concentration hydrochloric acid, and further centrifuged to separate and separate the catalyst residue. Thereafter, the hydrogenated copolymer polyol was precipitated in isopropyl alcohol and further sufficiently dried.
Then, 100 g of sufficiently dried hydrogenated copolymer polyol was dissolved in cyclohexane, and 2-acryloyloxyethyl isocyanate (manufactured by Showa Denko KK: Karenz AOI) was slowly added dropwise with stirring at 40 ° C. Then, the mixture was further stirred for 4 hours, precipitated in isopropyl alcohol and dried. The amount of 2-acryloyloxyethyl isocyanate added was 2.49 g. As described above, an acryloyl group-containing hydrogenated styrene-butadiene copolymer (hydrogenated SBR), which is a liquid photocurable resin, was obtained from the hydrogenated polymer polyol.

[Manufacture of hydrogenated BR]
After adding 1 mol of 1,3- (diisopropenyl) benzene to a fully dehydrated and purified cyclohexane solvent, 2 mol of triethylamine and 2 mol of sec-butyllithium are sequentially added and stirred at 50 ° C. for 2 hours. A dilithium polymerization initiator was prepared.
Next, a 7-liter polymerization reactor purged with argon was added to 1.35 kg of dehydrated and purified cyclohexane, 2.67 kg of a hexane solution of 22.9% by mass of 1,3-butadiene monomer, 1.6 mol / liter of OOPS (2 Then, 209.4 ml of a hexane solution of 2-bis (tetrahydrofuryl) propane) was added, and then 223.5 ml of a 0.5 mol / liter dilithium polymerization initiator was added to initiate the polymerization. Then, polymerization was carried out for 1.5 hours while raising the temperature of the polymerization reactor to 50 ° C. Then, 220.4 ml of a 1 mol / liter ethylene oxide cyclohexane solution was added and further stirred for 2 hours, and then 50 ml of isopropyl alcohol. Was added. A hexane solution of the polymer was precipitated in isopropyl alcohol and sufficiently dried to obtain a polymer polyol. This polymer polyol was OH group polybutadiene at both ends, the weight average molecular weight was 7,500, and the molecular weight distribution was 1.25.

  120 g of the above polymer polyol was dissolved in 1 liter of sufficiently dehydrated and purified hexane, and then a catalyst solution of nickel naphthenate, triethylaluminum and butadiene prepared in a separate container in a 1: 3: 3 (molar ratio) was co-polymerized. It charged so that it might become 1 mol of nickel with respect to 1000 mol of butadiene parts in a united solution. Hydrogen was pressurized to 27580 hPa (400 psi) in a sealed reaction vessel, and a hydrogenation reaction was performed at 110 ° C. for 4 hours. Thereafter, the catalyst residue was extracted and separated with hydrochloric acid of 3N concentration, and further centrifuged to separate the catalyst residue by sedimentation. Thereafter, the hydrogenated polymer polyol was precipitated in isopropyl alcohol and further sufficiently dried. Next, 100 g of a sufficiently dried hydrogenated polymer polyol was dissolved in cyclohexane, and 2-acryloyloxyethyl isocyanate (manufactured by Showa Denko KK: Karenz AOI) was slowly added dropwise while maintaining the temperature at 40 ° C. with sufficient stirring. The mixture was further stirred for 4 hours, precipitated in isopropyl alcohol and dried. The amount of 2-acryloyloxyethyl isocyanate added was 3.75 g. As described above, an acryloyl group-containing hydrogenated butadiene polymer (hydrogenated BR), which is a liquid photocurable resin, was obtained.

(Manufacture of urethane-based UV curable resin)
400 g of a polyester diol compound (number average molecular weight 2000) obtained from 2,4-diethyl-1,5-pentanediol and phthalic anhydride, 82.4 g of norbornane diisocyanate, and di-t-butyl as an antioxidant -0.10 g of hydroxy-phenol was added to a 1 liter four-necked flask equipped with a stirrer, a condenser, and a thermometer, and reacted at 80 ° C for 2 hours. Next, 46.2 g of 2-hydroxyethyl acrylate, 0.10 g of p-methoxyphenol as a polymerization inhibitor, and 0.06 g of titanium tetra (2-ethyl-1-hexanolate) were added and reacted at 85 ° C. for 6 hours to obtain a urethane oligomer. Obtained. Then, 1.5 g of 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, which is a photopolymerization initiator, was added to 100 g of the urethane oligomer to obtain a urethane UV curable resin.

(Production of photocurable composition)
Using the above-mentioned acryloyl group-containing hydrogenated styrene-butadiene copolymer, acryloyl group-containing hydrogenated butadiene polymer, and urethane-based UV curable resin, a photocurable composition having the formulation shown in Table 1 is obtained with a planetary mixer. It was.

(Examples 1-4, Comparative Examples 1-5)
The said photocurable composition was apply | coated to the surface of the base material which consists of a styrene-type thermoplastic elastomer composition mentioned above, the energy ray was irradiated to this, and the elastomer laminated body was obtained. A metal halide lamp was used as a light source for energy rays, and irradiation with energy rays was performed in an air atmosphere under the conditions of an illuminance of 160 mW / cm ² (wavelength 320 to 390 nm) and an integrated light quantity of 9000 mJ / cm ² .
And about the obtained elastomer laminated body, the adhesiveness, the presence or absence of oil oozing, and hardness were evaluated by the following method. The results are shown in Table 1.

(Conventional example 1)
With respect to the base material composed of the above-mentioned styrenic thermoplastic elastomer composition, the presence or absence of oil exudation was evaluated by the following method. As a result, oil ooze out.

(Adhesiveness)
It was evaluated whether or not the interface between the styrenic thermoplastic elastomer and the photocurable composition was easily torn by hand. The broken material was designated as “◯”, and the peeled material was designated as “X”.
(Existence of oil exudation)
The elastomer laminate was placed on the oil removing paper with the surface coated with the photocurable composition facing down. Then, a weight of 2 kg was placed on the elastomer laminate at a temperature of 60 ° C. for 24 hours. The presence or absence of exudation of oil was confirmed by visual inspection, and “O” indicates that there was no exudation, and “X” indicates that there was exudation.
(hardness)
A 1 mm thick elastomer laminate was stacked to a thickness of 6 mm, and the JIS-A hardness was measured.

* 1 Isobornyl acrylate, manufactured by Osaka Organic Chemical Industry

Claims (3)

A photocurable composition comprising a photocurable resin, a (meth) acrylate monomer, and a photopolymerization initiator on the surface of a substrate made of a styrene thermoplastic elastomer composition containing a styrene elastomer and oil. After applying the product, an elastomer laminate formed by irradiating the photocurable composition with energy rays and reaction curing,
The elastomer laminate, wherein the photocurable resin is a hydrogenated conjugated diene polymer, a hydrogenated conjugated diene-aromatic vinyl copolymer containing a photocurable functional group, or a mixture thereof. .   The ester residue of the (meth) acrylate monomer is an alkyl group having 12 to 18 carbon atoms, an isobornyl group, a dicyclopentanyl group, a cyclohexyl group, or a dicyclopentenyl group. An elastomer laminate.   The said photocurable composition contains the said (meth) acrylate monomer in the ratio of 1-150 mass parts with respect to 100 mass parts of said photocurable resins, The Claim 1 or 2 characterized by the above-mentioned. Elastomer laminate.