JP2008038117A - Resin composition and photocurable casting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocurable resin composition curable in an extremely short time by irradiation of energy ray and excellent in moldability. <P>SOLUTION: The resin composition comprises a photocurable resin composition composed of one or more kinds of urethane (meth)acrylate oligomers having one or more (meth)acryloyl groups at terminal(s) of molecule or on side chain(s) of molecule and having 5,000-100,000 molecular weight and one or more kinds of monofunctional (meth)acrylates, a silsesquioxane compound which is a compound represented by formula: (R<SB>0</SB>-SiO<SB>3</SB>/<SB>2</SB>)<SB>m</SB>(wherein R<SB>0</SB>is a hydrogen atom or at least on kind of functional group selected from a group consisting of a 1-6C alkyl group, a 1-6C alkoxy group, a 1-6C halogenated alkyl group, phenyl group, a halogen-substituted phenyl group, a hydroxy group, a (meth)acryloyl group, a vinyl group, a glycidyl group, an epoxy group and an oxetanyl group; m is a degree of polymerization), a photopolymerization initiator and at least one kind of an antioxidant and a light stabilizer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a photocurable resin composition and a cured product thereof, which can be cured in an extremely short time by irradiating energy rays such as ultraviolet rays and visible rays, and has excellent moldability. Light is injected into a mold made of a material capable of transmitting energy rays and cured by irradiating energy rays such as ultraviolet rays and visible rays from the outside of the mold to form a molded product. The present invention relates to a curing casting method.

In general, as a method of obtaining a molded product of plastic, a kneading step in which raw materials blended with a curing agent and other additives are sufficiently kneaded, and the kneaded dough is divided into a vacuum molding method, a pressure molding method, and an upper mold lower mold. The target molded body is obtained by molding by a heat-pressure molding method, an injection molding method, or the like using a molding die (hereinafter, also referred to as “upper and lower die”).

However, in the vacuum forming method, the pressure forming method, the heat pressing method using the upper and lower molds, etc., it is necessary to raise the mold temperature to near the melting point of the material, and enormous energy is required for heating. Moreover, since it is necessary to cool and take out the metal mold, it takes a long time for the molding cycle.

In the injection molding method, the melted resin is cooled immediately after coming into contact with a mold having a temperature difference, and the fluidity is extremely reduced. Therefore, it is difficult to obtain a thin molded body, and heating, injection, holding pressure, etc. This makes the equipment expensive. Further, since the thermoplastic material is heated to near the melting point, the heating energy is enormous.

In the above-mentioned vacuum forming method, pressure forming method, heating and press forming method using upper and lower molds, etc., the molding material is formed by molding a planar material that is substantially larger than the target part size, and then cutting out the part part for use. A lot of waste is generated, which is not preferable environmentally and economically.

The above-mentioned constituent materials of vacuum forming method, pressure forming method, and heat forming by upper and lower molds are generally materials of uniform thickness, so after forming, each part has the same thickness, and from the same material each part It is difficult to change the thickness.

In addition, the thickness of industrially manufactured materials is limited, and it is usually difficult to obtain materials with other thicknesses. A method of changing the thickness by a process such as stretching at the time of molding has also been proposed, but problems such as increased internal stress distortion after molding occur.

As means for solving the problems of the molding method as described above, an energy ray curable liquid substance is injected or filled into a mold made of a material capable of transmitting energy rays as described in Patent Documents 1 and 2, Examples thereof include a photo-curing cast molding method in which a cured product is formed by irradiation with energy rays such as ultraviolet rays and visible rays.
Japanese Patent No. 3140478 Japanese Patent No. 3197907

Furthermore, in the photo-curing cast molding method, by using an upper mold and a lower mold, a molded body can be obtained without destroying the mold, and a molded body can be repeatedly manufactured with the same mold.

More specifically, at least one of a pair of molds composed of an upper mold and a lower mold is formed of a material that transmits light, and a resin that can be cured by light irradiation is set to close the mold, This is a method of irradiating light from the outside of the mold to transmit and curing the resin to obtain a cured body of the desired shape. By this method, a molded body of any thickness can be easily and inexpensively produced with less energy and fewer man-hours. It becomes possible to do.

However, the resin compositions disclosed in Patent Documents 1 and 2 can satisfy moldability suitable for the above-mentioned photocuring and casting method, more specifically, low viscosity, low curing shrinkage, fast curability, and mold release property. It was not.

The present invention has been made in view of the state of the art, and can be cured in an extremely short time by irradiation with energy rays such as ultraviolet rays and visible rays, and can be cured with a photocurable resin composition excellent in moldability. Further, the resin composition is injected into a mold made of a material capable of transmitting energy rays, and cured by irradiating energy rays such as ultraviolet rays and visible rays from the outside of the mold, The present invention provides a photo-curing cast molding method characterized by forming.

The present invention is as follows.

（式中Ｒ_０は、水素原子、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜６のハロゲン化アルキル基、フェニル基、ハロゲンで置換されたフェニル基、ヒドロキシル基、（メタ）アクリロイル基、ビニル基、グリシジル基、エポキシ基、オキセタニル基のいずれから選ばれる１種以上の官能基を有し、ｍは重合度を表す。） (1) At least one of (A) a photocurable resin composition, (B) a silsesquioxane compound, (C) a photopolymerization initiator, (D) an antioxidant, and (E) a light stabilizer. The (A) photocurable resin composition has (A-1) one or more (meth) acryloyl groups at the terminal or side chain of the molecule, and the molecular weight is It consists of one or more urethane (meth) acrylate oligomers of 5,000 to 100,000 and (A-2) one or more monofunctional (meth) acrylates, and (B) a silsesquioxane compound is represented by the following formula [ 1] The resin composition characterized by the above-mentioned.

(In the formula, R ₀ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogenated alkyl group having 1 to 6 carbon atoms, a phenyl group, a phenyl group substituted with a halogen, (It has one or more functional groups selected from hydroxyl group, (meth) acryloyl group, vinyl group, glycidyl group, epoxy group, and oxetanyl group, and m represents the degree of polymerization.)

(2) (A) 0.001-100 mass parts of (B) silsesquioxane compound is contained with respect to 100 mass parts of photocurable resin composition, and the viscosity in 25 degreeC is 100-100,000 mPa * s. The resin composition as described in (1), which has a curing shrinkage ratio of 0 to 5%.

(3) (B) The silsesquioxane compound is a radical-reactive silsesquioxane compound containing a carbon-carbon unsaturated double bond in the molecule, according to (1) or (2) The resin composition as described.

(4) The resin composition as described in (3), wherein the (B) silsesquioxane compound is a (meth) acryl functional silsesquioxane compound containing a (meth) acryloyl group.

(5) The resin composition according to any one of (1) to (4), wherein the weight average molecular weight of the (B) silsesquioxane compound is in the range of 100 to 100,000.

(6) A cured product comprising the resin composition according to any one of (1) to (5).

(7) The resin composition according to any one of (1) to (6) is injected into a mold made of a material capable of transmitting energy rays, and cured by irradiation with energy rays from the outside of the mold. A light-curing cast molding method characterized by forming a molded body.

Since the resin composition of the present invention is cured in a very short time by light irradiation such as ultraviolet light or visible light, and has excellent moldability such as releasability and dimensional stability, the key for mobile phones It can be suitably used for sheet members such as sheets, resin molded products such as plastic lenses, plastic film materials, acoustics such as speakers, and various mechanism members. Moreover, since the photocuring cast molding method of the present invention uses the specific resin composition, it is possible to provide cured bodies having various shapes with high productivity.

As used herein, the term “molecular weight” means weight average molecular weight unless otherwise specified. The weight average molecular weight is measured by a known method such as gel permeation chromatography (GPC) and converted to standard polystyrene.

As used herein, the term “Tg” means glass transition temperature unless otherwise specified. The Tg of the resin composition is measured by a known method such as DSC or dynamic viscoelasticity.

The term “alkyl” as used herein refers to straight chain, branched and cyclic saturated hydrocarbon groups, unless otherwise specified.

As used herein, the term “viscosity” means “absolute viscosity” unless otherwise specified, and is defined as a proportional coefficient between a flow velocity gradient and a shear stress generated thereto, It can be measured with a viscometer such as an E-type viscometer or a rheometer.

The resin composition of the present invention is a photocurable resin composition that is irradiated with light to form a cured product. The light here means active energy rays typified by ultraviolet rays and visible rays. In achieving the object of the present invention, a resin composition comprising a specific urethane (meth) acrylate and a specific (meth) acrylate monomer is selected as the photocurable resin composition, and (A-1) molecule And one or more urethane (meth) acrylate oligomers having one or more (meth) acryloyl groups at the terminal or side chain and having a molecular weight of 5,000 to 100,000, and (A-2) monofunctional (meth) A resin composition (A) comprising at least one acrylate is selected.

The urethane (meth) acrylate oligomer that is the component (A-1) is composed of a polyol compound (hereinafter represented by X), an organic polyisocyanate compound (hereinafter represented by Y), and a hydroxy (meth) acrylate (hereinafter represented by Z). ) And a urethane (meth) acrylate oligomer.

Examples of the polyol compound (X) include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, 1,4-butanediol, polybutylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentane Diol, 2,2-butylethyl-1,3-propanediol, neopentyl glycol, cyclohexanedimethanol, hydrogenated bisphenol A, polycaprolactone, trimethylol ethane, trimethylol propylene , Polytrimethylolpropane, pentaerythritol, polypentaerythritol, sorbitol, mannitol, glycerin, polyglycerin, polytetramethylene glycol and other polyhydric alcohols, polyethylene oxide, polypropylene oxide, ethylene oxide / propylene oxide block or random copolymerization A polyether polyol having at least one structure of: a polyhydric alcohol or a polyether polyol and a polybasic acid such as maleic anhydride, maleic acid, fumaric acid, itaconic anhydride, itaconic acid, adipic acid, isophthalic acid, etc. Polyester polyol as a condensate, caprolactone-modified polyol such as caprolactone-modified polytetramethylene polyol, polyolefin-based polyol, polycarbonate Polyols, polybutadiene polyols, polyisoprene polyols, hydrogenated polybutadiene polyols, polydiene polyols such as hydrogenated polyisoprene polyols, silicone polyols such as polydimethylsiloxane polyols, etc., particularly preferably polyether polyols and polyester polyols It is.

The molecular weight of the polyol compound (X) is preferably 200 to 10,000, more preferably 500 to 8,000, and still more preferably 1,000 to 6,000. If the molecular weight is 200 or more, suitable moldability can be obtained, and if it is 10,000 or less, the curability does not deteriorate, which is preferable.

The organic polyisocyanate compound (Y) is not particularly limited. For example, aromatic, aliphatic, cycloaliphatic, and alicyclic polyisocyanates can be used. Isocyanate (TDI), diphenylmethane diisocyanate (MDI), hydrogenated diphenylmethane diisocyanate (H-MDI), polyphenylmethane polyisocyanate (crude MDI), modified diphenylmethane diisocyanate (modified MDI), hydrogenated xylylene diisocyanate (H-XDI) ), Xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), trimethylhexamethylene diisocyanate (TMXDI), tetramethylxylylene diisocyanate (m-TMXDI), isophorone diisocyanate Polyisocyanates such as nate (IPDI), norbornene diisocyanate (NBDI), 1,3-bis (isocyanatomethyl) cyclohexane (H6XDI), trimer compounds of these polyisocyanates, reaction products of these polyisocyanates and polyols, etc. Of these, hydrogenated xylylene diisocyanate (H-XDI) and isophorone diisocyanate (IPDI) are preferred. The molecular weight of the polyisocyanate compound (Y) is preferably 500 or less. If it is 500 or less, the reactivity with a diol will not fall.

Examples of the hydroxy (meth) acrylate (Z) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl acryloyl phosphate, and 4-butyl. Hydroxy (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, glycerin di (meth) acrylate, 2-hydroxy-3-acryloyloxypropyl (meth) acrylate, caprolactone modified 2-hydroxyethyl (Meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, etc. Of these 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate is preferably used.

In the urethane (meth) acrylate oligomer, the number of (meth) acryloyl groups in the molecule is 1 or more and 6 or less, more preferably 2 or more and 4 or less (meth) acryloyl groups at the end or side chain of the molecule. What has is preferable. When there is no (meth) acryloyl group, it cannot be copolymerized with the monofunctional (meth) acrylate which is the component (A-2), and when it is more than 6, the curing shrinkage of the resulting cured product becomes too large. This is because excellent moldability may not be obtained.

The molecular weight of the urethane (meth) acrylate oligomer is preferably 5,000 or more and 100,000 or less. If the molecular weight is 5,000 or more, the curing shrinkage rate is not excessively increased, and if it is 100,000 or less, the curability is not deteriorated, so that a cured product having excellent moldability can be obtained.

（式中、Ｒ^１は水素原子またはメチル基であり、Ｒ^２は、炭素数１〜２２である直鎖もしくは分岐アルキル基、シクロヘキシル基、炭素数１〜４の直鎖もしくは分岐アルキル基により置換されたシクロヘキシル基、フェニル基、炭素数１〜４の直鎖もしくは分岐アルキル基により置換されたフェニル基、ジシクロペンタニル基、ジシクロペンテニル基、ボルニル基、イソボルニル基、アダマンチル基、メチルアダマンチル基、アリル基である。）

（式中、Ｒ^１は水素原子またはメチル基であり、Ｒ^３は、炭素数１〜４である直鎖もしくは分岐アルキル基、Ｒ^４は、炭素数１〜４である直鎖もしくは分岐アルキル基、シクロヘキシル基、炭素数１〜４の直鎖もしくは分岐アルキル基により置換されたシクロヘキシル基、フェニル基、炭素数１〜４の直鎖もしくは分岐アルキル基により置換されたフェニル基、ジシクロペンタニル基、ジシクロペンテニル基、ボルニル基、イソボルニル基、アダマンチル基、メチルアダマンチル基、アリル基であり、ｎは１〜１２の整数である。） The monofunctional (meth) acrylate as the component (A-2) is not particularly limited as long as it contains one (meth) acryloyl group in the molecule, but is represented by the following formula [2] or [3]. A resin composition containing a monofunctional (meth) acrylate is particularly preferable because a cured product having excellent moldability can be obtained.

(In the formula, R ¹ is a hydrogen atom or a methyl group, and R ² is substituted by a linear or branched alkyl group having 1 to 22 carbon atoms, a cyclohexyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms. Cyclohexyl group, phenyl group, phenyl group substituted by a linear or branched alkyl group having 1 to 4 carbon atoms, dicyclopentanyl group, dicyclopentenyl group, bornyl group, isobornyl group, adamantyl group, methyladamantyl group , An allyl group.)

(In the formula, R ¹ is a hydrogen atom or a methyl group, R ³ is a linear or branched alkyl group having 1 to 4 carbon atoms, and R ⁴ is a linear or branched alkyl group having 1 to 4 carbon atoms. A cyclohexyl group, a cyclohexyl group substituted with a linear or branched alkyl group having 1 to 4 carbon atoms, a phenyl group, a phenyl group substituted with a linear or branched alkyl group having 1 to 4 carbon atoms, a dicyclopentanyl group And a dicyclopentenyl group, a bornyl group, an isobornyl group, an adamantyl group, a methyladamantyl group, and an allyl group, and n is an integer of 1 to 12.)

Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meta ) Acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, tridecyl (meth) acrylate, behenyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl ( (Meth) acrylate, propoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meta) Acrylate, methoxytetraethylene (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate , Methoxytripropylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, tert-butylcyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (Meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate 2-methyl-2-adamantyl (meth) acrylate, allyl (meth) acrylate and the like. Incidentally, with acrylate and methacrylate, methacrylate gives a cured body with more suitable moldability.

In the photocurable resin composition of the present invention, the blending ratio of the component (A-1) and the component (A-2) is in the range of 5:95 to 95: 5, particularly preferably 10:90. When it is in the range of ˜90: 10, a cured product obtained by light irradiation is particularly preferable because it has excellent moldability.

（式中Ｒ_０は、水素原子、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜６のハロゲン化アルキル基、フェニル基、ハロゲンで置換されたフェニル基、ヒドロキシル基、（メタ）アクリロイル基、ビニル基、グリシジル基、エポキシ基、オキセタニル基のいずれから選ばれる１種以上の官能基を有し、ｍは重合度を表す。） Further, the resin composition of the present invention contains a (B) silsesquioxane compound represented by the following formula [1] in order to obtain excellent moldability such as releasability and dimensional stability.

(In the formula, R ₀ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogenated alkyl group having 1 to 6 carbon atoms, a phenyl group, a phenyl group substituted with a halogen, (It has one or more functional groups selected from hydroxyl group, (meth) acryloyl group, vinyl group, glycidyl group, epoxy group, and oxetanyl group, and m represents the degree of polymerization.)

In the present invention, the silsesquioxane compound preferably used is a radical-reactive silsesquioxane compound containing an unsaturated double bond such as a (meth) acryloyl group or a vinyl group in the molecule. The average number of unsaturated double bonds in one molecule is preferably 1-50, particularly preferably 2-10.

Examples of the molecular structure of the silsesquioxane compound include various structures such as a ladder structure, a random structure, and a cage structure. However, the structure is not limited in the present invention, and any structure may be used alone. Or it may be a mixture of two or more.

The molecular weight of the silsesquioxane compound is preferably in the range of 100 to 100,000. If the molecular weight is 100 or more, excellent releasability and dimensional stability can be obtained. If the molecular weight is 100,000 or less, the viscosity of the liquid becomes too high, or there is a problem in the storage stability of the liquid. It does not occur.

The proportion of the silsesquioxane compound in the resin composition of the present invention is preferably 0.001 to 100 parts by mass with respect to 100 parts by mass of the component (A). If it is 0.001 part by mass or more, excellent releasability and dimensional stability can be obtained, and if it is 100 parts by mass or less, the viscosity of the liquid becomes too high, or there is a problem in the storage stability of the liquid. Does not occur.

The photopolymerization initiator as component (C) includes an ultraviolet polymerization initiator and a visible light polymerization initiator, and both are used without limitation. Examples of the photo radical polymerization initiator include benzoin, benzophenone, acetophenone, acylphosphine oxide, thioxanthone, metallocene, quinone, and boron.

In the present invention, as the photopolymerization initiator, for example, benzophenone, 4-phenylbenzophenone, benzoylbenzoic acid, 2,2-diethoxyacetophenone, bisdiethylaminobenzophenone, benzyl, benzoin, benzoylisopropyl ether, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, thioxanthone, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 1- (4- (2-hydroxyethoxy) -phenyl) -2-hydroxy-2 -Methyl-1-propan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, camphorquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6 -Trimethi Benzoyl) -phenylphosphine oxide, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) Examples include -1-butanone-1, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide.

Examples of the antioxidant as component (D) include β-naphthoquinone, 2-methoxy-1,4-noftquinone, methyl hydroquinone, hydroquinone, hydroquinone monomethyl ether, mono-tert-butyl hydroquinone, 2,5-di- quinone compounds such as tert-butylhydroquinone, p-benzoquinone, 2,5-diphenyl-p-benzoquinone, 2,5-di-tert-butyl-p-benzoquinone, phenothiazine, 2,2-methylene-bis (4- Methyl-6-tert-butylphenol), catechol, tert-butylcatechol, 2-butyl-4-hydroxyanisole, 2,6-di-tert-butyl-p-cresol, 2-tert-butyl-6- (3- tert-Butyl-2-hydroxy-5-methylbenz ) -4-methylphenyl acrylate, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl) ethyl] -4,6-di-tert-pentylphenyl acrylate, 4,4'-butylidenebis (6-tert-butyl-3-methylphenol), 4,4'-thiobis (6-tert-butyl-3-methylphenol), 3,9-bis [2- [3- (3-tert-butyl- 4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, pentaerythritol tetrakis [3- (3,5 -Di-tert-butyl-4-hydroxyphenyl) propionate], thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydride) Loxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, N, N′-hexane-1,6-diylbis [3- (3,5-di-) tert-butyl-4-hydroxyphenyl) propionamide], benzenepropanoic acid, 3,5-bis (1,1-dimethylethyl) -4-hydroxy, C7-C9 side chain alkyl ester, 2,4-dimethyl-6 -(1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, 3,3 ', 3 ", 5,5' , 5 "-hexa-tert-butyl-a, a ', a"-(mesitylene-2,4,6-tolyl) tri-p-cresol, calcium diethylbis [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [ 3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5- Tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris [( 4-tert-butyl-3-hydroxy-2,6-xylyl) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, N-phenylben Product of polyamine and 2,4,6-trimethylpentene, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) Phenolic compounds such as phenol, picric acid, citric acid, tris (2,4-di-tert-butylphenyl) phosphite, tris [2-[[2,4,8,10-tetra-tert-butyldibenzo [ d, f] [1,3,2] dioxaphosphine-6-yl] oxy] ethyl] amine, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis [ 2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid, tetrakis (2,4-di-tert-butylphenyl) [1,1-biphenyl Suphenyl] -4,4′-diylbisphosphonite, 6- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propoxy] -2,4,8,10-tetra-tert- Phosphorus compounds such as butyl dibenz [d, f] [1,3,2] dioxaphosphine, dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, distearyl 3, 3'-thiodipropionate, pentaerythrityltetrakis (3-laurylthiopropionate), sulfur compounds such as 2-mercaptobenzimidazole, amine compounds such as phenothiazine, lactone compounds, vitamin E compounds, etc. Among them, phenolic compounds are preferable.

Examples of the light stabilizer as the component (E) include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis (1,2,2,6,6-pentamethyl-4-piperidyl). ) Sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl]- 4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, 1,2,2,6,6-pentamethyl-4 -Piperidinyl-methacrylate, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methy Butyl malonate, decanedioic acid bis (2,2,6,6-tetramethyl-1 (octyloxy) -4-piperidinyl) ester, reaction product of 1,1-dimethylethyl hydroperoxide and octane, N, N ', N ", N"'-tetrakis- (4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) amino) -triazine-2- Yl) -4,7-diazadecane-1,10-diamine, dibutylamine, 1,3,5-triazine, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl-1, 6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine polycondensate, poly [[6- (1,1,3,3-tetramethylbutyl) amino- 1,3,5-G Azine-2,4-diyl] [(2,2,6,6-tetramethyl-4-piperidyl) imino] hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl) imino]], Polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, 2,2,4,4-tetramethyl-20- (β-lauryloxycarbonyl) ethyl-7 -Oxa-3,20-diazadispiro [5 · 1 · 11 · 2] heneicosan-21-one, β-alanine, N,-(2,2,6,6-tetramethyl-4-piperidinyl) -dodecyl ester / Tetradecyl ester, N-acetyl-3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidinyl) pyrrolidine-2,5-dione, 2,2,4,4-tetramethyl- -Oxa-3,20-diazadispiro [5,1,11,2] heneicosane-21-one, 2,2,4,4-tetramethyl-21-oxa-3,20-diazadicyclo- [5,1,11 , 2] -Heneicosane-20-propanoic acid dodecyl ester / tetradecyl ester, propanedioic acid, [(4-methoxyphenyl) -methylene] -bis (1,2,2,6,6-pentamethyl-4-piperidinyl ) Ester, higher fatty acid ester of 2,2,6,6-tetramethyl-4-piperidinol, 1,3-benzenedicarboxamide, N, N′-bis (2,2,6,6-tetramethyl-4 Hindered amines such as -piperidinyl), benzophenone compounds such as octabenzone, 2- (2H-benzotriazol-2-yl) -4- (1 , 1,3,3-tetramethylbutyl) phenol, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimide-methyl) ) -5-methylphenyl] benzotriazole, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert- Pentylphenyl) benzotriazole, methyl 3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate and polyethylene glycol reaction product, 2- (2H-benzotriazole -2-yl) -6-dodecyl-4-methylphenol and other benzotriazole compounds Benzoate series such as 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate, 2- (4,6-diphenyl-1,3,5-triazine-2- Yl) -5-[(hexyl) oxy] phenol and the like, and hindered amine compounds are particularly preferable.

In the resin composition of the present invention, with respect to 100 parts by mass of component (A), 0.01 to 15 parts by mass of component (C), and the total amount of components (D) and (E) is 0.01. When it is set as the composition containing 10 mass parts, since the obtained hardened | cured material has the outstanding sclerosis | hardenability and moldability, it is especially preferable.

Furthermore, the viscosity of the resin composition of the present invention is 100 to 100,000 mPa · s at 25 ° C., and the curing shrinkage is 0% or more and 5% or less. If the viscosity of the resin composition is 100 mPa · s or higher, liquid leakage or the like will not occur, and a molded product of the desired shape will not be obtained. As a result, the cured product of the desired shape cannot be obtained. In addition, when the curing shrinkage rate is 0% or more and 5% or less, a cured product having a target shape can be obtained without causing a difference in mold accuracy and cured product.

Furthermore, in the resin composition of the present invention, a rubber composition can be blended to impart impact resistance and vibration fatigue durability.

Examples of rubber compositions include conventional elastomers such as natural rubber, modified natural rubber, grafted natural rubber, cyclized natural rubber, chlorinated natural rubber, styrene-butadiene rubber, chloroprene rubber, acrylonitrile-butadiene rubber, carboxylated nitrile rubber, Nitrile rubber / vinyl chloride resin blend, nitrile rubber / EPDM rubber blend, butyl rubber, brominated butyl rubber, chlorinated butyl rubber, ethylene-vinyl acetate rubber, acrylic rubber, ethylene-acrylic rubber, chlorosulfonated polyethylene, chlorinated polyethylene, epichlorohydrin rubber , Rubber materials such as epichlorohydrin-ethylene oxide rubber, methyl silicone rubber, vinyl-methyl silicone rubber, phenyl-methyl silicone rubber, fluorosilicone rubber, polystyrene thermoplastic Elastomers, polyvinyl chloride thermoplastic elastomers, polyolefin thermoplastic elastomers, polyurethane thermoplastic elastomers, polyester thermoplastic elastomers, polyamide thermoplastic elastomers, vinyl chloride thermoplastic elastomers, fluororubber thermoplastic elastomers, chlorinated Thermoplastic elastomer materials such as polyethylene elastomer can be exemplified, and among them, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and acrylic rubber are particularly preferable from the viewpoint of compatibility with the photocurable resin.

In the present invention, if necessary, pigments (titanium white, cyanine blue, watching red, bengara, carbon black, aniline black, manganese blue, iron black, ultramarine blue are used as long as the effects of the present invention are not impaired. , Hansa Red, Chrome Yellow, Chrome Green, etc.), inorganic fillers (calcium carbonate, kaolin, clay, talc, mica, barium sulfate, lithopone, limestone, zinc stearate, perlite, quartz, quartz glass, fused silica, spherical Silica powder such as silica, etc., oxides such as spherical alumina, crushed alumina, magnesium oxide, beryllium oxide and titanium oxide, nitrides such as boron nitride, silicon nitride and aluminum nitride, carbides such as silicon carbide, water Hydroxides such as aluminum oxide and magnesium hydroxide, , Silver, iron, aluminum, nickel, titanium and other metals and alloys, diamond, carbon and other carbon-based materials), thermoplastic resins and thermosetting resins (nylon-6, nylon-6,6, etc. polyamides) Resin, vinyl chloride resin, nitrocellulose resin, vinylidene chloride resin, acrylic resin, acrylamide resin, styrene resin, vinyl ester resin, polyester resin, fluorine resin, acrylic rubber, urethane rubber, etc. Various elastomer resins, methyl methacrylate-butadiene-styrene graft copolymers and graft copolymers such as acrylonitrile-butadiene-styrene graft copolymers), reinforcing agents (glass fibers, carbon fibers, etc.), anti-sagging agents (Hydrogenated castor oil, fine particulate succinic anhydride, etc.), matting agents (fine silica, para Inwakkusu etc.), it is also possible to blend the abrasive (zinc stearate).

In addition to the above components, an antifoaming agent, a flame retardant, an antistatic agent, a plasticizer, a thermal polymerization initiator, a silane coupling agent, an adhesion imparting agent, and the like can be used in combination.

By irradiating the resin composition of the present invention obtained as described above with light, it is possible to obtain a cured product that is cured in an extremely short time and that is excellent in moldability such as releasability and dimensional stability. it can.

Moreover, when the molded body of the resin composition of the present invention is molded, various methods can be adopted as the means, and the following two methods are particularly preferable. (1) At least one of a set of molds including an upper mold and a lower mold is formed of a material that transmits light, and a predetermined amount of the photocurable resin composition before curing is disposed. Next, the upper mold and the lower mold are pressure-bonded, the mold is closed, light is irradiated from the outside of the mold made of a material that transmits light, and the resin is cured to obtain a desired cured body, or (2) At least one of a set of upper and lower molds is formed of a light-transmitting material, then the upper and lower molds are crimped, closed, and then pre-formed on the mold A predetermined amount of the photo-curable resin composition before curing is injected from the injection port. And the method of irradiating light from the outer side of the type | mold consisting of the material which permeate | transmits light, hardening a resin, and obtaining the target hardening body.

Examples of the material used for the mold that transmits light include glass materials such as quartz, quartz glass, borosilicate glass, and soda glass, acrylic resin, polycarbonate resin, polystyrene resin, polyester resin, polyethylene resin, polypropylene resin, fluororesin, Examples thereof include resin materials such as cellulose resin, styrene-butadiene copolymer, methyl methacrylate-styrene copolymer, silicone resin, and polycycloolefin resin. Among them, an acrylic resin such as polymethyl methacrylate is particularly preferable because it is excellent in transparency, durability, and can be manufactured at low cost, and the excellent moldability exhibited by the resin composition of the present invention by using the acrylic resin. It can be maximized.

Examples of the light source include a halogen lamp, a metal halide lamp, a high power metal halide lamp (containing indium and the like), a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, a xenon excimer lamp, and a xenon flash lamp.

Since the emission wavelength and energy distribution are different, the light source is selected depending on the reaction wavelength of the photopolymerization initiator. Natural light (sunlight) can also be a reaction initiation light source.

The light source can be directly irradiated, focused with a reflecting mirror or the like, or focused with a fiber or the like, and a low wavelength cut filter, a heat ray cut filter, a cold mirror, or the like can also be used.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

<Examples 1-5 and Comparative Examples 1-4>
Each type of component shown in Tables 1-2 was mixed with the composition shown in the table to prepare a photocurable resin composition. In addition, the following compounds were selected for each component described in Tables 1-2.

(A-1) The urethane (meth) acrylate oligomer having at least one (meth) acryloyl group at the end or side chain of the component molecule and having a molecular weight of 5,000 to 100,000 is the following (a1): Was used. In addition, the molecular weight as described below is a weight average molecular weight in terms of standard polystyrene measured by gel permeation chromatography (GPC) (solvent: tetrahydrofuran (THF)).
(A1) Polyester polyol urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., UV-3000B molecular weight: 18,000),
Moreover, the compound of the following (a2) was used as urethane (meth) acrylate which does not satisfy | fill the molecular weight 5,000-100,000 in (A-1).
(A2) Polyester polyol-based urethane acrylate (SD-7 molecular weight: 3,500, manufactured by Negami Kogyo Co., Ltd.).

The following (a3) and (a4) were used as the monofunctional (meth) acrylate of the component (A-2).
(A3) Dicyclopentanyl methacrylate (Hitakuri FA-513M, manufactured by Hitachi Chemical Co., Ltd.),
(A4) n-butyl methacrylate (Kyoeisha Chemical Co., Ltd. light ester NB).

The following (b1) and (b2) were used as the silsesquioxane compound which is the mold release agent for the component (B).
(B1) Silsesquioxane (1)
(Toagosei Co., Ltd .: polyacryloyloxypropyl polyorganosilsesquioxane (AC-SQ)),
(B2) Silsesquioxane (2)
(Manufactured by ALDRICH: octa [2- (4-cyclohexenyl) ethyldimethylsilyloxy] polyorganosilsesquioxane (CH-SQ)).

As the photopolymerization initiator of component (C),
Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (IRGACURE 819 manufactured by Ciba Specialty Chemicals Co., Ltd.)
Was used.

As the antioxidant of component (D),
Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (IRGANOX 1076, manufactured by Ciba Specialty Chemicals Co., Ltd.)
Was used.

As the light stabilizer of component (E),
Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (Sanol LS-770, manufactured by Sankyo Lifetech Co., Ltd.)
Was used.

Various physical properties were measured as follows.

(Viscosity measurement)
Measurement was performed at 25 ° C. using a B-type viscometer. In addition, about the thing whose viscosity exceeds 100,000 mPa * s, since the resin injection property to a type | mold was very bad, the subsequent evaluation was stopped.

(Curability evaluation)
Using a fusion belt conveyor type UV curing device equipped with an electrodeless discharge lamp (D bulb), curing is performed under the condition that the total irradiation amount to the photocurable resin is 4000 mJ / cm ² (365 nm) as the curing condition. Evaluation was made with ◯ for those that were tack-free by the finger, △ for those that were cured but with no tack remaining on the surface, and × for those that were not cured at all. In addition, about the evaluation which was evaluation x, the subsequent evaluation was stopped.

[Curing shrinkage]
The specific gravity dL of the resin composition before curing is JIS Z8804 (liquid specific gravity measurement method-3. Specific gravity measurement method using specific gravity bottle), and the specific gravity dS of the resin composition after curing is JIS Z8807 (solid specific gravity measurement method-4. Liquid. The measurement was performed at 23 ° C., and the curing shrinkage ratio r (%) was calculated according to r (%) = {1− (dL / dS)} × 100.

[Light irradiation conditions]
As light irradiation conditions in each evaluation, a belt conveyor type ultraviolet curing device manufactured by Fusion equipped with an electrodeless discharge lamp (D bulb) was used, and the cumulative irradiation amount to the photocurable resin was 4000 mJ / cm ² (365 nm). Curing was performed under the following conditions.

[Evaluation of releasability]
The upper mold consists of a 100 mm × 100 mm × 5 mm thick acrylic resin plate, and a lower mold that imitates a recess of 25 mm × 25 mm × depth 0.2 mm at the center of one side of the same shape of the acrylic resin plate as the upper mold A set of molds was prepared, and the required amount of the pre-curing photocurable resin composition was dropped into the recesses of the lower mold. Next, the upper mold was put on the lower mold, pressure-bonded and the mold was closed, and the resin composition was cured by irradiating light from the outside of the upper mold under the irradiation conditions described above. After curing, connect a digital push-pull gauge (RX-20 manufactured by AIKOH ENGINEERING CO. Ltd.) to the center of the upper mold, and pull the push-pull gauge in a direction perpendicular to the mold surface while fixing the lower mold. Thus, the tensile strength necessary to peel off the upper mold was measured. Even if the value of the push-pull gauge exceeded 8.0 kgf, the case where the upper mold was not peeled off was judged as releasability x, and the case where it was peeled off at 8.0 kgf or less was judged as releasability ○.

The result of moldability evaluation of the obtained resin composition is summarized and shown in Tables 1-2.

Since the resin composition of the present invention is cured in a very short time by light irradiation such as ultraviolet light or visible light, and has excellent moldability such as releasability and dimensional stability, the key for mobile phones It can be suitably used for sheet members such as sheets, resin molded products such as plastic lenses, plastic film materials, acoustics such as speakers, and various mechanism members. Moreover, since the photocuring cast molding method of the present invention uses the specific resin composition, it can provide variously shaped cured bodies with high productivity, and is very useful in industry.

Claims (7)

(A) a photocurable resin composition, (B) a silsesquioxane compound, (C) a photopolymerization initiator, (D) an antioxidant, and (E) at least one of a light stabilizer. (A) The photocurable resin composition has (A-1) one or more (meth) acryloyl groups at the terminal or side chain of the molecule, and the molecular weight is 5,000. It consists of one or more urethane (meth) acrylate oligomers of ~ 100,000 and one or more (A-2) monofunctional (meth) acrylates, and (B) the silsesquioxane compound is represented by the following formula [1]. The resin composition characterized by being the compound represented.

(In the formula, R ₀ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogenated alkyl group having 1 to 6 carbon atoms, a phenyl group, a phenyl group substituted with a halogen, (It has one or more functional groups selected from hydroxyl group, (meth) acryloyl group, vinyl group, glycidyl group, epoxy group and oxetanyl group, and m represents the degree of polymerization.) (A) 0.001-100 mass parts of (B) silsesquioxane compounds are contained with respect to 100 mass parts of photocurable resin composition, and the viscosity in 25 degreeC is the range of 100-100,000 mPa * s. The resin composition according to claim 1, wherein the curing shrinkage ratio is 0 to 5%. (B) The resin according to claim 1 or 2, wherein the silsesquioxane compound is a radical-reactive silsesquioxane compound containing a carbon-carbon unsaturated double bond in the molecule. Composition. The resin composition according to claim 3, wherein the (B) silsesquioxane compound is a (meth) acryl functional silsesquioxane compound containing a (meth) acryloyl group. (B) The weight average molecular weight of a silsesquioxane compound is the range of 100-100,000, The resin composition as described in any one of Claims 1-4 characterized by the above-mentioned. The hardening body which consists of a resin composition as described in any one of Claims 1-5. The resin composition according to any one of claims 1 to 5 is injected into a mold made of a material capable of transmitting energy rays, and cured by irradiating energy rays from the outside of the mold, and then molded. A photocuring casting method characterized by forming a body.