JP2010285469A - Method for producing photocurable resin for electronic parts, photocurable resin for electronic parts, sealant for electronic parts - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a non-staining photocurable resin for electronic parts, which can efficiently promote a urethane reaction in a urethanizing process; to provide a photocurable resin for electronic parts, obtained by the production method; and to provide a sealant for electronic parts, using the same. <P>SOLUTION: There are provided the method for producing the photocurable resin for the electronic parts, including a reaction process for reacting a conjugated diene-based polymer polyol or a conjugated diene-aromatic vinyl-based copolymer polyol with a photocurable unsaturated hydrocarbon group-containing compound in the presence of a titanium-based catalyst, wherein the ratio (X:Y) of the hydroxyl group equivalent (X) of the polyol in the conjugated diene-based polymer polyol or the conjugated diene-aromatic vinyl-based copolymer polyol to the photocurable unsaturated hydrocarbon group-containing compound equivalent (Y) is 1:1.5 to 1:2.5; the photocurable resin for the electronic parts, obtained by the production method; and the sealant for electronic parts, prepared by curing the photocurable resin. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a photocurable resin for electronic components, a photocurable resin for electronic components, and a sealing material for electronic components.

  In recent years, various photocurable resins have been developed for applications such as sealing materials and adhesives. As a process for producing such a photocurable resin, a urethanization process in which the terminal hydroxyl group of a polymer having a hydroxyl group at a terminal is reacted with acryloyloxyethyl acrylate is known (for example, see Patent Document 1). In such a process, a catalyst containing Sn or Pb may be used to promote the urethane reaction. However, when such a photocurable resin is used for an electronic component, non-contamination is required, and thus the catalyst containing Sn or Pb cannot be used.

  As a catalyst for satisfying the non-polluting requirement, a Ti chelate complex catalyst (for example, see Patent Documents 2 and 3) and a Ti alkylate catalyst (for example, see Patent Documents 4 to 6) have been proposed.

  However, simply applying these catalysts to the urethanization process described above may result in excessive supply of reaction raw materials, which may prevent efficient urethane reaction, and reaction conditions in the urethanization process. It was necessary to optimize.

JP 2007-145949 A JP-A-57-155255 Special table 2001-501534 gazette JP-T-2004-526858 JP-T-2006-506416 JP 2007-197507 A

  In view of the above, an object of the present invention is to provide a method for producing a photocurable resin for electronic components that can efficiently promote the urethane reaction in the urethanization process and has non-contamination properties. Moreover, an object of this invention is to provide the photocurable resin for electronic components obtained by the said manufacturing method, and the sealing material for electronic components using the same.

  As a result of intensive studies to achieve the above object, the present inventors have arrived at the present invention that can achieve the object. That is, the present invention is as follows.

[1] including a reaction step of reacting a conjugated diene polymer polyol or a conjugated diene-aromatic vinyl copolymer polyol with a photocurable unsaturated hydrocarbon group-containing compound in the presence of a titanium catalyst, Ratio of hydroxyl group equivalent (X) of polyol in the conjugated diene polymer polyol or the conjugated diene-aromatic vinyl copolymer polyol (X: photocurable unsaturated hydrocarbon group-containing compound equivalent (Y)) A method for producing a photocurable resin for electronic parts, wherein Y) is from 1: 1.5 to 1: 2.5.
[2] The method for producing a photocurable resin for electronic components according to [1], further including a removing step of removing the unreacted photocurable unsaturated hydrocarbon group-containing compound after the reaction step.
[3] The method for producing a photocurable resin for electronic components according to [2], wherein in the removing step, the treatment for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound is a filtration treatment.
[4] The method for producing a photocurable resin for electronic parts according to [2], wherein in the removing step, the treatment for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound is a solvent extraction treatment.
[5] A photocurable resin for electronic parts produced by the production method according to any one of [1] to [4].
[6] A sealing material for electronic parts obtained by curing the photocurable resin for electronic parts according to [5].
[7] The sealing material for electronic parts according to [6], which is a gasket material.

  ADVANTAGE OF THE INVENTION According to this invention, the urethane reaction can be efficiently accelerated | stimulated in a urethanization process, and the manufacturing method of the photocurable resin for electronic components which has non-contamination property can be provided. Moreover, the photocurable resin for electronic components obtained by the said manufacturing method and the sealing material for electronic components using the same can be provided.

[Photocurable resin for electronic parts and method for producing the same]
The photocurable resin for electronic parts of the present invention comprises a conjugated diene polymer polyol or a conjugated diene-aromatic vinyl copolymer polyol and a photocurable unsaturated hydrocarbon group-containing compound in the presence of a titanium catalyst. It is manufactured through a reaction process in which

  By passing through this process, a photocurable unsaturated hydrocarbon group-containing compound is reacted with a conjugated diene polymer polyol or a conjugated diene-aromatic vinyl copolymer polyol, thereby producing a photocurable unsaturated hydrocarbon group. A photocurable resin into which is introduced can be obtained.

  The conjugated diene polymer polyol or conjugated diene-aromatic vinyl copolymer polyol here is a hydrogenated conjugated diene polymer having no unsaturated double bond in the main chain through a hydrogenation step described later. The polyol or hydrogenated conjugated diene / aromatic vinyl copolymer polyol (hereinafter, also referred to as “hydrogenated (co) polymer polyol according to the present invention”) is included.

  In the reaction step, the ratio between the hydroxyl group equivalent (X) of the polyol in the conjugated diene polymer polyol or conjugated diene-aromatic vinyl copolymer polyol and the photocurable unsaturated hydrocarbon group-containing compound equivalent (Y). (X: Y) is set to 1: 1.5 to 1: 2.5. If the ratio is less than 1: 1.5, the urethane reaction does not proceed sufficiently, and if it exceeds 1: 2.5, for example, it is difficult to remove excess acryloyloxyethyl acrylate (for example, Showa Denko KK). End up. The ratio is preferably 1: 1.7 to 1: 2.3, and more preferably 1: 1.9 to 1: 2.1.

Titanium-based catalysts used in the reaction process include titanium alkoxides such as titanium tetraisopropoxide, titanium tetranormal butoxide, titanium butoxide dimer, titanium tetra-2-ethylhexoxide; titanium diisopropoxybis (acetylacetonate) ), Titanium tetraacetylacetonate, titanium dioctyloxybis (octylene glycolate), titanium diisopropoxybis (ethyl acetoacetate), titanium diisopropoxybis (triethanolaminate), titanium lactate ammonium salt, titanium lactate And titanium chelates such as titanium lactate; and titanium acylates such as polyhydroxytitanium stearate. Of these, titanium diisopropoxybis (ethyl acetoacetate) is preferable from the viewpoint of handling.
The titanium catalyst is preferably present in an amount of 100 ppm to 1000 ppm with respect to the polymer.

  The conjugated diene polymer polyol or the conjugated diene-aromatic vinyl copolymer polyol according to the present invention is reacted with a photocurable unsaturated hydrocarbon group-containing compound, and the end of the polyol is not photocurable. In order to introduce a saturated hydrocarbon group, the photocurable unsaturated hydrocarbon group is preferably an acryloyl group or a methacryloyl group. Here, as a photocurable unsaturated hydrocarbon group containing compound, acryloyl isocyanate and methacryloyl isocyanate are preferable, and said hydrogenated (co) polymer polyol is (meth) acrylated by reaction with these.

  Examples of acryloyl isocyanate include 2-acryloyloxyethyl isocyanate, and examples of methacryloyl isocyanate include 2-methacryloyloxyethyl isocyanate.

  The temperature at which the photocurable unsaturated hydrocarbon group-containing compound is reacted with the conjugated diene polymer polyol or the conjugated diene-aromatic vinyl copolymer polyol is preferably 40 to 120 ° C, preferably 60 to More preferably, the temperature is set to 100 ° C.

  In the method for producing a photocurable resin for electronic components of the present invention, a removal step for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound is provided after the above-described reaction step, or before the reaction step. In addition, processes such as a polymer production process, a polyol production process, and a polyol hydrogenation process may be provided. Hereinafter, these steps will be described.

(Removal process)
In the removal step, the unreacted photocurable unsaturated hydrocarbon group-containing compound is removed after the reaction step. The treatment for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound is preferably either a filtration treatment or a solvent extraction treatment. Filtration treatment is preferable in terms of easy operation, and solvent extraction treatment is preferable in terms of production efficiency.

  Examples of the filtration treatment include a treatment of adding 0.5 to 10% by mass of water to the polymer, stirring for 0.5 to 3 hours, and allowing to stand for about 1 day to precipitate crystals, followed by filtration. As solvent extraction treatment, conjugated diene polymer polyol or conjugated diene-aromatic vinyl copolymer polyol: solvent (heptane etc.) is set to 1: 3 to 1: 2, and water: methanol (mass ratio) 20:80. About half of the conjugated diene polymer polyol or conjugated diene-aromatic vinyl copolymer polyol is added to the mixture, (1) stirred for 20 to 60 minutes, and (2) left to stand for 20 to 60 minutes and extracted. The process which performs the process (process of (1) and (2)) to perform at least twice is mentioned.

(Polymer production process)
In the polymer production process, a conjugated diene monomer, or a conjugated diene monomer and an aromatic vinyl monomer are polymerized with a dilithium initiator in a saturated hydrocarbon solvent to produce a conjugated diene heavy polymer. A polymer or a conjugated diene / aromatic vinyl copolymer (hereinafter sometimes referred to as “(co) polymer according to the present invention”) is produced. Since the main polymerization is living anionic polymerization, the polymerization can be performed while controlling the molecular weight and molecular weight distribution. The molecular weight can be obtained by polymerizing 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 5,000 or more, a narrow polymer having a molecular weight distribution of 2 or less Easy to get. If desired, anionic polymerization may be carried out in the presence of a randomizer.

  Examples of the conjugated diene monomer include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, 2-phenyl-1,3-butadiene, 1,3-hexadiene, and the like. Can be mentioned. These may be used singly or in combination of two or more. Among these, 1,3-butadiene or isoprene is preferable from the viewpoint of securing rubber elasticity after curing.

  As the aromatic vinyl monomer, styrene, α-methylstyrene or paramethylstyrene is preferable from the viewpoint of rubber physical properties after curing. These may be used alone or in combination of two or more.

  The dilithium initiator is not particularly limited, and known ones can be used. For example, Japanese Patent Publication No. 1-53681 discloses a method for producing a dilithium initiator by reacting a monolithium compound with a disubstituted vinyl or an alkenyl group-containing aromatic hydrocarbon in the presence of a tertiary amine. ing.

  Monolithium compounds used when producing a dilithium initiator include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, tert-octyl lithium, and n-decyl. Examples thereof include 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 preferable.

  Examples of the tertiary amine used when producing the dilithium initiator include lower aliphatic amines such as trimethylamine and triethylamine, N, N-diphenylmethylamine, and the like, and 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 are preferred.

  The solvent used in the preparation of the above dilithium initiator and the production of the (co) polymer may be any organic solvent inert to the reaction, and hydrocarbons such as aliphatic, alicyclic and aromatic hydrocarbon compounds. System solvents are used, for example, n-butane, 1-butane, n-pentane, 1-pentane, cis-2-butene, trans-2-butene, 1-butene, n-hexane, n-heptane, n- One or two selected from octane, 1-octane, methylcyclopentane, cyclopentane, cyclohexane, 1-hexene, 2-hexene, 1-pentene, 2-pentene, benzene, toluene, xylene, ethylbenzene, etc. . Of these, n-hexane and cyclohexane are usually used.

(Polyol production process)
In the polyol production process, the conjugated diene polymer polyol or conjugated having hydroxyl groups at both ends of the (co) polymer according to the present invention by reacting an equivalent of the polymer end which is a living anion and alkylene oxide. A diene / aromatic vinyl copolymer polyol (hereinafter sometimes referred to as “(co) polymer polyol according to the present invention”) is obtained.

  Moreover, as an alkylene oxide used for the polyolation reaction which reacts with the terminal which is the living anion of the (co) polymer according to the present invention to generate a hydroxyl group at both terminals, for example, ethylene oxide, propylene oxide, butylene oxide, etc. Can be mentioned. This polyol reaction is preferably performed immediately after the polymerization reaction.

  If the weight average molecular weight of the (co) polymer polyol according to the present invention obtained by the above-mentioned polyolation reaction is 5,000 or more, the molecular weight between crosslinking points can be increased, and the elastic modulus is lowered after the photocuring reaction. In addition, when the molecular weight is 40,000 or less, the polymerization viscosity does not become too high when the polymerization is performed with a dilithium catalyst, and it is not necessary to lower the solid content concentration as a polymerization process. Therefore, it becomes low cost and preferable.

  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. In the present invention in which a (co) polymer having a narrow molecular weight distribution can be synthesized, an (co) polymer having the same molecular weight can be obtained with good reproducibility, and therefore, an effect of stabilizing the viscosity can be expected. In many cases, the liquid material as in the present invention is applied by a dispenser. In this case, since the variation in the material viscosity causes a variation in the dimension after the application, the stabilization of the viscosity is important, and the molecular weight distribution is 3. It is preferably 0 or less.

(Polymer hydrogenation process)
In the polyol hydrogenation step, the (co) polymer polyol according to the present invention having a double bond in the main chain is subjected to a hydrogenation reaction (hereinafter referred to as a hydrogenation reaction), whereby the main chain is unsaturated double. A hydrogenated conjugated diene polymer polyol or a hydrogenated conjugated diene / aromatic vinyl copolymer polyol (hydrogenated (co) polymer polyol according to the present invention) having no bond is obtained.
Here, the (co) polymer means “polymer or copolymer”.

  The hydrogenation reaction in the method of the present invention is carried out by hydrogenating the (co) polymer polyol according to the present invention in the presence of a hydrogenation catalyst in an organic solvent under hydrogen pressure. The hydrogenation catalyst used in the method of the present invention is a heterogeneous catalyst such as palladium-carbon, reduced nickel or rhodium; or an organic nickel compound such as nickel naphthenate or nickel octoate, or an organic such as cobalt naphthenate or cobalt octoate. A homogeneous catalyst in which a cobalt compound and an organoaluminum compound such as triethylaluminum and triisobutylaluminum or an organolithium compound such as n-butyllithium and sec-butyllithium are combined can be used. As a cocatalyst, an ether compound such as tetrahydrofuran, ethylene glycol dimethyl ether, or diethylene glycol dimethyl ether may be used.

Further, as another hydrogenation reaction method, for example, the (co) polymer according to the present invention before hydrogenation is mixed with dicyclopentadienyl titanium halide, organic carboxylate nickel, organic carboxylate nickel and the periodic table. Hydrogenation catalysts composed of Group I to III organometallic compounds, catalysts for nickel, platinum, barium, ruthenium, rhenium, rhodium metal catalysts, cobalt, nickel, rhodium, ruthenium complexes, etc. supported on carbon, silica, diatomaceous earth, etc. As follows: under hydrogen pressurized to 1 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, the presence of a hydrogen storage alloy such as LaNi ₅ alloy, or pressurized to 1 to 100 atm hydrogen And a hydrogenation catalyst obtained by mixing di-p-tolyl-bis (1-cyclopentadienyl) titanium / cyclohexane solution and n-butyllithium / n-hexane solution under hydrogen The method of hydrogenating under hydrogen pressurized to 1 to 100 atm.

Among the various hydrogenation catalysts described above, a Ziegler hydrogenation catalyst or a palladium-carbon hydrogenation catalyst comprising a combination of a transition metal compound and an alkylaluminum compound is preferred.
Such transition metal compounds include tris (acetylacetonato) cobalt, bis (acetylacetonato) nickel, tris (acetylacetonato) iron, tris (acetylacetonato) chromium, tris (acetylacetonato) manganese, bis (acetyl). Acetonato) manganese, tris (acetylacetonato) ruthenium, bis (acetylacetonato) cobalt, bis (cyclopentadienyl) dichlorotitanium, bis (cyclopentadienyl) dichlorozirconium, bis (triphenylphosphine) cobalt dichloride, Examples thereof include 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. Dichloride, ethylaluminum dichloride, isobutylaluminum dichloride, diethylaluminum hydride, diisobutylaluminum hydride, ethylaluminum sesquichloride. Among these, triisobutylaluminum, triethylaluminum, and diisobutylaluminum hydride are preferable from the viewpoint of hydrogenation activity, and triisobutylaluminum is most preferable.

  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 alkyl aluminum compound react previously and adding it to a polymerization solution can be mentioned preferably. The amount of the alkylaluminum compound used in this case 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 performed at a temperature of 50 to 180 ° C., preferably 70 to 150 ° C., and 5 to 100 atm (5,066.625 to 101,325 hPa), preferably 10 to 50 atm (10132.5 to 50, 662.5 hPa). If the hydrogenation temperature is lower than 50 ° C., and if the hydrogen pressure is lower than 5 atm, the catalyst activity may be low, which is not preferable. If the hydrogenation temperature exceeds 180 ° C., deactivation of the catalyst, side reactions, etc. may occur. This is not preferable because it may occur easily. In general, a Ziegler-type hydrogenation catalyst is a catalyst having extremely high hydrogenation activity, and it is not preferable to set the hydrogen pressure to 100 atm (101,325 hPa) or more because it is not necessary and the burden on the apparatus increases.

  As described above, the photocurable resin obtained by the production method of the present invention is usually used as a photocurable composition. The photocurable resin is preferably contained in an amount of 20% by mass or more, more preferably 30% by mass or more based on the entire photocurable composition. As a component other than the photocurable resin, a (meth) acrylic acid ester monomer, a radical photopolymerization initiator, an inorganic filler, and / or an organic thickener are preferably used.

[Photocurable composition]
The photocurable composition according to the present invention is, for example, a kneader capable of adjusting the temperature of each component including the photocurable resin of the present invention and an additive component used as desired, for example, a single screw extruder, a twin screw It can manufacture by kneading | mixing using an extruder, a planetary mixer, a twin screw mixer, a high shear mixer, etc.

  The (meth) acrylic acid ester monomer not only reduces the viscosity of the photocurable composition before curing, but also improves various physical properties after curing. That is, it is possible to improve the adhesive strength, decrease the hardness, improve Eb (elongation), and Tb (breaking strength). The (meth) acrylic acid ester monomer preferably has a molecular weight of less than 1,000, more preferably 150 to 600.

(Meth) acrylic acid ester monomers include cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, diethylene glycol monoethyl ether (meth) Acrylate, dimethylaminoethyl (meth) acrylate, dimethylol dicyclopentane di (meth) acrylate, dipropylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, ethoxylated phenyl (meth) acrylate, ethyl (meth) acrylate, Isoamyl (meth) acrylate, isobornyl (meth) acrylate, isobutyl (meth) acrylate, isodecyl (meth) acrylate, isooctyl (Meth) acrylate, isostearyl (meth) acrylate, isomyristyl (meth) acrylate, lauroxypolyethylene glycol (meth) acrylate, lauryl (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripylene glycol (meth) Examples include acrylate, methoxypolyethylene glycol (meth) acrylate, and methoxytriethylene glycol acrylate. Of these, dicyclopentanyl acrylate, dicyclopentenyl acrylate, and isobornyl acrylate are preferred in the present invention.
In addition, (meth) acrylate means an acrylate or a methacrylate.

  The compounding amount of the (meth) acrylic acid ester monomer is (meth) with respect to 30 to 100 parts by mass of the photocurable resin when the photocurable resin and the (meth) acrylic acid ester monomer are combined to be 100 parts by mass. 70-0 mass parts of acrylic ester monomers are preferable, More preferably, it is 60-10 mass parts of (meth) acrylic acid ester monomers with respect to 40-90 mass parts of photocurable resins.

  In particular, if the (meth) acrylic acid ester monomer is 10 parts by mass or more, the effect of reducing the viscosity of the photocurable composition can be enjoyed, and extrusion, discharge, etc. are facilitated, and it becomes easy to form a sealing material or the like. Moreover, if it is 60 mass parts or less, the viscosity of this composition will not become low too much, and it will become difficult to flow down the sealing material etc. immediately after formation. Furthermore, since the adhesive strength and elasticity of the cured sealing material and the like are ensured, the airtightness is not easily lost.

  As radical photopolymerization initiators, benzoin derivatives, benzyl ketals [for example, Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure 651], α-hydroxyacetophenones [for example, Ciba -Specialty Chemicals Co., Ltd., trade names: Darocur 1173, Irgacure 184, Irgacure 127], α-aminoacetophenones [for example, Ciba Specialty Chemicals, Inc., trade names: Irgacure 907, Irgacure 369], Combination use of α-aminoacetophenones and thioxanthones (for example, isopropylthioxanthone, diethylthioxanthone), acylphosphine oxides [for example, Ciba Specialty Chemicals, Inc., trade name: Irgacure 8 9], and the like, as a hydrogen abstraction type, combined use of benzophenones and amines, combination and the like of the thioxanthone and amine. Further, an intramolecular cleavage type and a hydrogen abstraction type may be used in combination. Among these, oligomerized α-hydroxyacetophenone and acrylated benzophenones are preferable. More specifically, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone] [for example, Lamberti S. et al. p. A product, trade name: ESACURE KIP150, etc.], acrylated benzophenone [for example, trade name: Ebecryl P136, etc., manufactured by Daicel UCB Co., Ltd.], imide acrylate, and the like.

  In addition to the above-mentioned radical photopolymerization initiators, 1- [4- (2-hydroxyethoxy) phenyl] -2-methyl-1-propan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone 1-hydroxy-cyclohexyl-ketone and benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,4,6-trimethylbenzoylphenylphosphine oxide, 2,4,6- Trimethylbenzoylphenylphenylethoxyphosphine oxide, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2- Methyl-1-[(4-methylthio) phenyl] -2-morpholinopro 1-one, 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, mixture of 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer and 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone , Methyl o-benzoylbenzoate, [4- (methylphenylthio) phenyl] phenylmethane, and the like can also be used.

  The radical photopolymerization initiator amount blended in the photocurable composition according to the present invention is 0.1 to 6 parts by mass with respect to a total of 100 parts by mass of the photocurable resin and the (meth) acrylic acid ester monomer. It is preferably 0.5 to 4 parts by mass, more preferably 1 to 3 parts by mass.

When an inorganic filler and / or an organic thickener is blended with the photocurable composition according to the present invention, the composition can have thixotropy and the moldability of the composition can be improved.
Examples of inorganic fillers include silica (SiO ₂ ), alumina, titania, and viscosity minerals, among which silica powder, silica powder subjected to hydrophobic treatment, or a mixture thereof is preferable. More specifically, silica fine powder pulverized by a dry method [for example, product name: Aerosil 300 manufactured by Nippon Aerosil Co., Ltd.], fine powder obtained by modifying this silica fine powder with trimethyldisilazane [for example, Japan Aerosil Co., Ltd., trade name: Aerosil RX300, etc.] and fine powder obtained by modifying the above silica fine powder with polydimethylsiloxane [for example, Nippon Aerosil Co., Ltd., trade name: Aerosil RY300, etc.].

The average particle diameter of the inorganic filler is preferably 5 to 50 μm, more preferably 5 to 12 μm, from the viewpoint of thickening and thixotropy.
The amount of the inorganic filler blended in the photocurable composition according to the present invention is 0.1 to 10 parts by mass with respect to 100 parts by mass in total of the photocurable resin and the (meth) acrylic acid ester monomer. Preferably, it is 0.5-7 mass parts, More preferably, it is 1-5 mass parts.

  As the organic thickener, hydrogenated castor oil, amide wax or a mixture thereof is preferable. Specifically, as an organic thickener, hydrogenated castor oil which is a hydrogenated product of castor oil (non-drying oil whose main component is ricinoleic acid) [for example, product name: ADVITROL100, Enomoto Kasei Co., Ltd. Product name: Disparone 305, etc.] and high-grade amide wax which is a compound having an amide bond [for example, trade name: Disparon 6500, manufactured by Enomoto Kasei Co., Ltd.], and the like.

  The amount of the organic thickener blended in the photocurable composition according to the present invention is 0.1 to 10 parts by mass with respect to a total of 100 parts by mass of the photocurable resin and the (meth) acrylic acid ester monomer. Is preferable, more preferably 0.5 to 7 parts by mass, and still more preferably 1 to 5 parts by mass.

  In the photocurable composition according to the present invention, a terminal (meth) acrylate oligomer can be blended in addition to or as an alternative to the (meth) acrylic acid ester monomer. By blending this terminal (meth) acrylate oligomer, the viscosity of the photocurable composition can be adjusted, and physically, the hardness is reduced, and Eb (elongation) and Tb (breaking strength) are improved. Etc. can be achieved.

  The terminal (meth) acrylate oligomer refers to an oligomer having an acryloyl group or a methacryloyl group at one end or both ends. The terminal (meth) acrylate oligomer is preferably a hydrocarbon oligomer, that is, a hydrogenated oligomer or a terminal (meth) acrylate hydrogenated oligomer, from the viewpoint of moisture permeability, weather resistance and heat resistance. The weight average molecular weight of the terminal (meth) acrylate oligomer is preferably 5,000 to 40,000. When the weight average molecular weight is within this range, there are advantages that it is easy to handle as a liquid raw material and the cured product has low hardness.

  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. As the polyester (meth) acrylate oligomer, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, or It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to a polyvalent carboxylic acid with (meth) acrylic acid.

  The epoxy (meth) acrylate 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 novolak type epoxy resin and esterifying it. Alternatively, it can be modified with isocyanate and the terminal hydroxyl group can be esterified with acrylic acid.

  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 of polyether polyol or polyester polyol and polyisocyanate with (meth) acrylic acid.

  The amount of the terminal (meth) acrylate oligomer blended in the photocurable composition according to the present invention is 30 to 100 parts by mass with respect to 100 parts by mass in total of the photocurable resin and the (meth) acrylic acid ester monomer. Is more preferable, and it is 40-90 mass parts more preferably. However, the (meth) acrylic acid ester monomer and the terminal (meth) acrylate oligomer may be mutually substituted if desired.

  A stabilizer or the like may be further added to the photocurable composition according to the present invention. As a stabilizer, triethylene glycol bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate] [for example, Ciba Specialty Chemicals Co., Ltd., trade name: IRGANOX245, Asahi Manufactured by Denka Kogyo Co., Ltd., trade 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 [for example, manufactured by Asahi Denka Kogyo Co., Ltd., trade name: ADK STAB AO-80, etc.] Etc.

  The amount of the stabilizer compounded in the photocurable composition according to the present invention is 0.1 to 5 parts by mass with respect to 100 parts by mass in total of the photocurable resin and the (meth) acrylic acid ester monomer. More preferably, it is 0.5-3 mass parts, More preferably, it is 0.5-2 mass parts.

  Further, the photocurable composition according to the present invention includes a terpene resin, a terpene phenol resin, a coumarone resin, a coumarone-indene resin, and a petroleum hydrocarbon within the range not impairing the effects of the present invention. Additives such as various tackifiers such as rosin derivatives and colorants such as titanium black can be added.

[Sealant for electronic parts]
The sealing material for electronic components of the present invention is obtained by curing a photocurable resin for electronic components, for example, as a photocurable composition according to the present invention.

Specifically, the sealing material of the present invention can be produced by applying a photocurable composition to an adherend and curing it by irradiation with energy rays.
As the adherend, for example, one made of a hard resin can be used, but a metal one is preferable from the viewpoint of workability. There is no particular limitation on the metal, for example, cold-rolled steel sheet, galvanized steel sheet, aluminum / zinc alloy plated steel sheet, stainless steel sheet, aluminum plate, aluminum alloy plate, magnesium plate, magnesium alloy plate, etc. Can be used. Moreover, what injection-molded magnesium can also be used. From the viewpoint of corrosion resistance, a metal subjected to electroless nickel plating is preferable. As this electroless nickel plating method, a known method conventionally applied to metal materials, for example, nickel sulfate, sodium hypophosphite, lactic acid, propionic acid and the like containing pH 4.0-5. A method of immersing a metal plate in an electroless nickel plating bath made of an aqueous solution having a temperature of about 0 and a temperature of about 85 to 95 ° C. can be used.

  In addition, applications of the sealing material include electronic parts such as HDD gaskets, ink tank seals, and liquid crystal seals. The thickness of the sealing material can be appropriately selected depending on the application, but is usually about 0.1 to 2.0 mm.

  Application of the photocurable composition to a substrate such as an adherend can be performed by an arbitrary method using a coating liquid in which the temperature of the composition is adjusted as necessary and adjusted to a constant viscosity, For example, methods such as gravure coating, roll coating, spin coating, reverse coating, bar coating, screen coating, blade coating, air knife coating, dipping, dispensing, and inkjet can be used. After apply | coating and shape | molding the said photocurable composition, an application layer is hardened by irradiating an energy ray, and a sealing material can be obtained.

The active energy ray used for reaction / curing refers to ultraviolet rays and ionizing radiation such as electron rays, α rays, β rays, and γ rays, and ultraviolet rays are preferred in the present invention. 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.
Further, the properties can be stabilized by irradiating active energy rays again after curing or by applying heat.

  If the cured product has a JIS-A hardness of 55 or less, measured with a type A durometer after being reacted and cured by irradiation with active energy rays, a sufficient sealing property can be obtained, which is preferable. From the same viewpoint, it is more preferably 10 to 55, further preferably 20 to 55, and particularly preferably 25 to 52.

Further, it is preferable that the moisture permeability after the curing is 40 g / m ² · 24 h or less because the function as a sealing material or a gasket is sufficiently exhibited. Particularly preferably, it is 15 g / m ² · 24 h or less.

  In the sealing material, the cross-sectional shape of the sealing layer is such that the sealing layer is higher than the sealing layer width 1 from the viewpoint of efficiently using a space in an electronic device such as an HDD or a printing device while ensuring good sealing performance. Is preferably 0.2 to 2.0, more preferably 0.3 to 2.0. When the height cannot be obtained at one time, it can be applied in several times. In this case, it is possible to cure by irradiating energy rays every time one step is applied.

  The sealing material for electronic parts of the present invention is suitable as a gasket material, and particularly suitable as a gasket material for a hard disk device.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the weight average molecular weight obtained the weight average molecular weight by polystyrene conversion using GPC method (Gel Permeation Chromatography).

(Manufacture of polymer)
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.

  Into a 7-liter polymerization reactor purged with argon, 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 (2-2 ′ After adding 209.4 ml of a hexane solution of -di (tetrahydrofuryl) propane), 223.5 ml of a 0.5 mol / liter dilithium polymerization initiator was added to initiate polymerization.

  Polymerization was performed 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 the mixture was further stirred for 2 hours, and then 50 ml of isopropyl alcohol was added. did. 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.

Example 1
After 120 g of polymer polyol was dissolved in 1 liter of fully dehydrated and purified heptane, a catalyst solution of nickel naphthenate, triethylaluminum and butadiene prepared in a separate container in a 1: 3: 3 (molar ratio) was copolymerized. The amount of nickel was charged to 1 mol per 1,000 mol of butadiene in the solution. Hydrogen was added under pressure to 27,580 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.

  Then, it concentrated so that the volume ratio of hydrogenated polymer polyol and heptane might be set to 1: 1, and the moisture content in a system was 200 ppm or less. Next, acryloyloxyethyl acrylate is added so that the ratio of the hydroxyl group equivalent (X) of the polyol in the hydrogenated polymer polyol to the photocurable unsaturated hydrocarbon group-containing compound equivalent (Y) is as shown in Table 1 below. In the state of 80 ° C., titanium tetraisopropoxide (Orgatechs TA-10 manufactured by Matsumoto Fine Chemical Co., Ltd.) is added so that the content becomes 300 to 2000 ppm, and stirred for 5 hours. A resin was prepared.

  After adding a photopolymerization initiator to the prepared photocurable resin for electronic parts, UV irradiation and acryloyl-isocyanate and hydrogenation based on the knowledge that if the acrylated (= urethane reaction) progresses, the hardness will increase The reactivity with the polymer was measured by replacing it with hardness. The results are shown in Table 1 below.

(Example 2)
For electronic components in the same manner as in Example 1 except that titanium diisopropoxybis (ethylacetoacetate) (Orgatechs TC-750 manufactured by Matsumoto Fine Chemical Co., Ltd.) was used as the titanium-based catalyst instead of titanium tetraisopropoxide. A photocurable resin was prepared. The produced photocurable resin for electronic components was measured in the same manner as in Example 1 to evaluate the reaction rate. The results are shown in Table 2 below.

(Comparative Example 1)
A photocurable resin for electronic parts was produced in the same manner as in Example 1 except that a Bi-based catalyst (bismuth octylate) was used instead of the Ti-based catalyst. The produced photocurable resin for electronic components was measured in the same manner as in Example 1 to evaluate the reaction rate. The results are shown in Table 3 below.

Claims (7)

A reaction step of reacting a conjugated diene polymer polyol or a conjugated diene-aromatic vinyl copolymer polyol with a photocurable unsaturated hydrocarbon group-containing compound in the presence of a titanium-based catalyst,
Ratio of hydroxyl group equivalent (X) of polyol in the conjugated diene polymer polyol or the conjugated diene-aromatic vinyl copolymer polyol (X: photocurable unsaturated hydrocarbon group-containing compound equivalent (Y)) A method for producing a photocurable resin for electronic parts, wherein Y) is from 1: 1.5 to 1: 2.5.   The manufacturing method of the photocurable resin for electronic components of Claim 1 including the removal process of removing the said unreacted said photocurable unsaturated hydrocarbon group containing compound after the said reaction process.   The process for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound in the removing step is a filtration process, The method for producing a photocurable resin for electronic components according to claim 2.   The process for removing the unreacted photocurable unsaturated hydrocarbon group-containing compound in the removing step is a solvent extraction process according to claim 2.   The photocurable resin for electronic components manufactured by the manufacturing method of any one of Claims 1-4.   The sealing material for electronic components formed by hardening | curing the photocurable resin for electronic components of Claim 5.   The sealing material for electronic parts according to claim 6, which is a gasket material.