KR101790646B1 - Soluble polyfunctional (meth)acrylic ester copolymer, and method for production thereof, curable resin composition and cured product - Google Patents

Abstract

A copolymer which has excellent optical properties such as low color dispersion and high light transmittance and which is excellent in various characteristic balance required for optical lens and prism material and does not cause branching of refractive index even under severe working conditions such as moist heat condition, To provide a resin composition.
(Meth) acrylic acid ester (a) having an alicyclic structure, a monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group, a bifunctional (meth) acrylic acid ester (c) (Meth) acrylate group having a reactive (meth) acrylate group derived from (c) at the side chain and having a structural unit derived from (d) at the terminal, wherein the copolymer is a copolymer obtained by copolymerizing a component containing Soluble multifunctional (meth) acrylic acid ester copolymer, and a curable resin composition containing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a soluble polyfunctional (meth) acrylic acid ester copolymer, a process for producing the same, a curable resin composition and a cured product,

The present invention has excellent optical properties such as low chromatic dispersion and high light transmittance, heat resistance and processability, and also has excellent optical characteristics under low humidity conditions such as wet heat conditions, low absorptivity (low water absorption) (Meth) acrylic acid ester copolymer having an alicyclic structure and an alcoholic hydroxyl group improved in adhesion to a material, a process for producing the same, and a curable resin composition and a cured product using the same.

 Most of the monomers having unsaturated bonds with reactive activity can cleave the unsaturated bonds and generate multimers by selecting the appropriate reaction conditions and the catalyst that causes the chain reaction. Generally, the types of monomers having unsaturated bonds vary widely, and the richness of the types of resins obtained is also remarkable. However, the kind of monomer capable of obtaining a high molecular weight substance having a molecular weight of 10,000 or more, which is generally referred to as a polymer compound, is relatively small. And examples thereof include ethylene, substituted ethylene, propylene, substituted propylene, styrene, alkylstyrene, alkoxystyrene, norbornene, various acrylic esters, butadiene, cyclopentadiene, dicyclopentadiene, isoprene, maleic anhydride, maleimide , Fumaric acid ester, allyl compound and the like can be given as representative monomers. A variety of various resins are synthesized by solely or copolymerizing these monomers.

The use of these resins is mainly limited to the relatively inexpensive consumer electronic devices, and there is hardly any application to high-tech fields requiring high heat resistance, dimensional stability and fine workability in the field of optoelectronic materials. The reason for this is that the polymer synthesized from the above-mentioned monomers is usually thermoplastic, and since it is necessary to use a high molecular weight material in order to satisfy the mechanical properties, the properties required in high technology fields such as heat resistance and fine workability are sacrificed .

As a method for solving the drawbacks of such a vinyl-based thermoplastic polymer, Patent Documents 1 to 3 disclose a polymer having a (meth) acryloyl group or a vinyl ether group in a pendant. For example, Patent Document 1 discloses a photosensitive composition comprising a (meth) acryloyl group pendant-type polymer and a photopolymerization initiator obtained by cationic polymerization of a heterogeneous polymerizable monomer such as 2-vinyloxyethyl (VEA) . Patent Document 2 discloses a photosensitive composition comprising a (meth) acryloyl group pendant polymer, a compound having a photoreactive unsaturated carboxyl group, and a photopolymerization initiator. Also, Patent Document 3 discloses that a heteropolymeric monomer such as 2-vinyloxyethyl (VEA) acrylate is used as a monomeric polymerization catalyst in a carboxylic acid ester solvent compound having a photoreactive unsaturated group which is inert to its own cationic polymerization And then polymerizing or copolymerizing the polymer solution to obtain a polymer solution.

However, when a reactive polymer produced according to the technique using the heteropolymerizable monomers disclosed in these patent documents is used, the characteristic balance such as low absorptivity, moldability, heat resistance and high transparency required in advanced optical lens / A polymer having improved optical properties under adverse yarn operating conditions such as wet heat conditions and improved adhesion to an inorganic material has not been obtained.

On the other hand, Patent Document 4 discloses a method for producing a polyurethane resin having a structural unit obtained by copolymerizing a monovinyl aromatic compound and a bifunctional (meth) acrylic acid ester and having a structural unit containing a reactive (meth) acrylate group derived from a bifunctional (meth) Functional vinyl aromatic copolymers are disclosed. However, the soluble polyfunctional vinyl aromatic copolymer obtained by the technique disclosed in the patent document has excellent heat-decomposability against thermal history at high temperature, has a reactive (meth) acrylate group in the side chain, is excellent in workability, Although it has solubility, there is a limitation in practical use that it can not be used for an optical lens for low-color dispersion, but it is a material which has not improved adhesion with an inorganic material.

Patent Document 5 discloses that a methyl methacrylate (MMA) syrup contains 1 to 25% by weight of a di (meth) acrylate of a straight chain aliphatic divalent alcohol having 4 to 8 carbon atoms as a constituent component Compositions are disclosed. The production of the MMA-based syrup composition disclosed in the patent document is carried out in the presence of MMA or MMA and a vinyl copolymer or chain transfer agent copolymerizable therewith in an inert gas atmosphere (for example, N ₂ gas) , Or at room temperature or by heating polymerization. Specific examples of the chain transfer agent in the published patent publication are only sulfur compounds such as lauryl mercaptan, thioglycolic acid octyl ester, thiocresol, thionaphthol and benzyl mercaptan, and 2,4-diphenyl-4- Methyl-1-pentene (d) has not been specifically disclosed. Further, the structural unit derived from 2,4-diphenyl-4-methyl-1-pentene and the monofunctional (meth) acrylic acid ester (a) having an alicyclic structure coexist, so that the refractive index It has not been suggested that it is possible to inhibit the occurrence of the disease. In addition, the composition obtained by the technique disclosed in the patent document is not improved in adhesion with an inorganic material under a severe working condition such as a humid condition.

Patent Document 6 discloses a polymerizable composition comprising a vinyl monomer and a di (meth) acrylate compound, and the use of 2,4-diphenyl-4-methyl-1-pentene (d) , And the amount of use thereof is about several percent of comma as a chain transfer agent, and the product also shows no cross-linking gelatinous solubility.

Patent Document 7 also discloses a method of producing a magnetic recording medium comprising a magnetic recording layer comprising a constituent unit composed of 1) an epoxy group-containing (meth) acrylate, 2) a hydroxyl group-containing (meth) acrylate, 3) a (meth) acrylic acid, A thermosetting resin composition for a color filter comprising a curable copolymer and an organic solvent is disclosed. The self-curing copolymer obtained by the technique disclosed in the patent document can be used in the polymerization step in order to achieve a desired molecular weight range, such as mercaptopropionic acid, mercaptopropionic acid ester, thioglycol, thioglycerin, dodecylmercaptan, and a known molecular weight regulator such as? -methylstyrene dimer can be used. However, in the technique disclosed in this patent document, since no bifunctional or more functional vinyl compound having a plurality of vinyl groups is added during polymerization, only one or more end groups derived from a molecular weight modifier can be introduced into the polymer chain, There is a drawback that the functions can not be sufficiently given. Further, in the patent publication, the self-curable copolymer obtained by the disclosed technique has a problem that although a thermosetting resin composition is formed in a resin composition with an epoxy resin, a curing reaction does not occur with the acrylate resin , There is a drawback that the strength and heat resistance of the blended resin composition are lowered.

Therefore, it is an object of the present invention to provide an optical material which has excellent optical properties such as low color dispersion and high light transmittance and has a characteristic balance such as low absorptivity, moldability and heat resistance and also has improved optical characteristics under adverse yarn- Soluble polyfunctional (meth) acrylic acid ester copolymers have not existed so far.

On the other hand, the thermosetting resin composition is useful as, for example, mechanical parts materials, electric / electronic parts materials, automobile parts materials, civil engineering building materials, molding materials and the like, and is also used as a material for paints and adhesives. Furthermore, when a hybrid member is used in combination with an inorganic base material, not only the thermal expansion rate can be lowered, but also the appearance of the resin composition and its cured product can be controlled by adjusting the refractive index of the inorganic substance and the resin, , Materials for electric / electronic parts materials and optical applications. For example, the digital camera module is mounted on a cellular phone and is being miniaturized, and it is also required to be reduced in cost. Furthermore, as a new application, there is an increasing need for a car-mounted camera or a barcode reader for a courier. When applied to these applications, heat resistance of shape retention is required not to change the shape of the molded product during solder reflow at the time of production, and heat resistance and low water absorption property for a long period of time And the like.

With respect to this technical requirement, Patent Document 8 discloses a composition containing (a) colloidal silica dispersed in an organic solvent, (b) an alicyclic polyepoxy compound and (c) a metal chelate compound as essential components, (a) and (b) is 100 to 100% by weight based on the solid content of the component (a) and the component (b) 0.01 to 30 parts by weight per part by weight of the organic solvent-based thermosetting composition. Patent Documents 9 to 11 disclose an epoxy resin molded article molded by curing a composition comprising at least an epoxy resin and inorganic oxide particles, wherein an inorganic oxide particle having an average particle diameter of 50 nm or less is dispersed in the molded article have. When the material obtained by the techniques disclosed in these documents is subjected to a severe thermal history at reflow at a temperature of 280 DEG C or more, heat discoloration is insufficient and it is necessary to improve the optical characteristics after receiving the thermal history.

On the other hand, in Patent Document 12, at least one (meth) acrylate (a) having a bifunctional condensed polycyclic alicyclic structure and silica fine particles (b) having an average particle size of 1 to 100 nm are dispersed in an organic solvent A molded cured product obtained by crosslinking a composite composition containing 30 to 90 wt% of silica fine particles (b) in a composite composition obtained by removing an organic solvent from a composition comprising silica. However, the molded cured product obtained according to the technique of this document does not have the moldability required for continuous molding of a high-precision shape such as an optical lens or a prism.

Patent Document 13 discloses a curable resin composition for an optical material containing a vinyl polymer having repeating structural units derived from a heteropolymerizable monomer having a specific structure and zirconium oxide particles having an average particle size of 1 nm to 100 nm.

Here, zirconium oxide particles having an average particle size of 1 nm to 100 nm are used as the inorganic fine particles. When such a material is used as an optical lens of an image pickup system, since it becomes a highly dispersed material, it is necessary to improve the optical characteristics in order to reduce the blur of light and to obtain a material having a high Abbe number. In addition, when a severe thermal history at the time of reflow at a high temperature is received, it is necessary to improve the optical characteristics after receiving the thermal history due to the lack of heat resistance with respect to the shape retention.

When a curable composite composition produced according to the techniques disclosed in these documents is used, it has a characteristic balance such as low absorptivity, moldability, heat resistance and high transparency required in advanced optical lens / prism applications, , Shape accuracy and stability of heat-resistant shape maintenance stability, and has not obtained a curable resin composition which has high optical properties and can be suitably applied for continuous molding of various optical members.

Japanese Patent Publication No. 49-13212 Japanese Patent Publication No. 51-34433 Japanese Patent Publication No. 54-27394 Japanese Patent Application Laid-Open No. 2008-247978 Japanese Patent Application Laid-Open No. 57-167340 Japanese Patent Application Laid-Open No. 2002-121228 Japanese Patent Application Laid-Open No. 2009-1770 Japanese Patent Publication No. 2865741 Japanese Patent Application Laid-Open No. 2004-250521 Japanese Patent Application Laid-Open No. 2008-133439 Japanese Patent Application Laid-Open No. 2008-156625 Japanese Patent Publication No. 4008246 Japanese Patent Application Laid-Open No. 2009-92598

(Meth) acrylate group having excellent curability in the side chain and has excellent optical properties such as low chromatic dispersion and high light transmittance, and is required for optical lens / prism material in advanced technical fields such as low absorptivity, workability and heat resistance. (Meth) acrylic acid ester copolymer which is excellent in balance of various characteristics as well as being improved in optical properties under adverse yarn operating conditions such as wet heat conditions and adhesion to inorganic materials, and a process for producing the copolymer with high efficiency The purpose is to provide. The present invention also provides a curable resin composition having excellent optical properties such as low color dispersion and high light transmittance, heat resistance, hardness and processability, and improved heat resisting property in the shape of a molded article under severe mounting conditions such as reflow conditions and cured products thereof .

(B) a bifunctional (meth) acrylic acid ester (c) having an alicyclic hydroxyl group, a bifunctional (meth) acrylic acid ester (c) having an alicyclic structure, (Meth) acrylic ester (c) derived from a bifunctional (meth) acrylic acid ester (c) is added to the side chain, And having a structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d) at the terminal thereof, and having a weight average molecular weight of 2000 to 20,000, and further containing toluene, xylene, Soluble polyfunctional (meth) acrylic acid ester copolymer soluble in dichloroethane or chloroform.

The availability of the present invention, polyfunctional (meth) acrylate copolymer is represented by the mole fraction of 2,4-diphenyl-4-methyl-1 (d) to the introduced amount of the structural unit derived from the formula (1) (M _d ) Is preferably 0.02 to 0.35.

M _d = (d) / [(a) + b + c + d]

In addition, a 0.05 to 0.5 as a bifunctional (meth) mole fraction (M _c1) of acrylic acid ester (c) (c1) represented by the introduced amount of the reactive (meth) acrylate group (c1), the following equation (2) derived from Is satisfied.

M _c1 = (c1) / [(a) + (b) + c]

In the formulas (1) and (2), the structural units (a), (b), (c), (d) and (c1) derived from the monofunctional (meth) acrylic acid ester , A structural unit derived from a monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group, a structural unit derived from a bifunctional (meth) acrylic acid ester (c) The number of moles of the structural unit derived from pentene (d) and the structural unit containing a bifunctional (meth) acrylate group in the side chain.

Wherein the monofunctional (meth) acrylic acid ester (a) is selected from the group consisting of isobonyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, At least one monofunctional (meth) acrylic acid ester selected from the group consisting of dicyclopentanyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentenyloxyethyl methacrylate, and dicyclopentanyl methacrylate , The monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group is selected from the group consisting of 2-hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate and partially ethoxylated 2-hydroxy methacrylate (Meth) acrylic acid ester having at least one alcoholic hydroxyl group selected, and the bifunctional (meth) It is preferable that the acrylic acid ester (c) is at least one bifunctional (meth) acrylic acid ester selected from the group consisting of cyclohexanedimethanol diacrylate and dimethyloltricyclodecane diacrylate.

The present invention also relates to a process for the preparation of (b) a process for the production of 2,4-diphenyl-4-methyl-1-pentene, wherein (d) is present in an amount of 10 to 500 parts by weight per 100 parts by weight of the bifunctional (meth) 2 to 55 mol% of monofunctional (meth) acrylic acid ester (a), 2 to 50 mol% of monofunctional (meth) acrylic acid ester (b) having alcoholic hydroxyl group and 2 To 10 mol% of the monomer component is polymerized at a temperature of 50 to 200 캜. The present invention also provides a process for producing a soluble polyfunctional (meth) acrylic acid ester copolymer.

Also,

(A): soluble polyfunctional (meth) acrylic acid ester copolymer according to claim 1,

(B): a monomer having at least one functional group having an unsaturated double bond and having a molecular weight of 1000 or less, and

(C): fine particles of silica having an average particle size of 1 to 100 nm,

Of the curable resin composition.

(B) is contained in an amount of from 83 to 2 wt%, the amount of the component (C) is more than the amount of the component (C) in the curable resin composition, Preferably 15 to 90 wt%. It is also preferable that the component B is at least one (meth) acrylate ester selected from a monofunctional (meth) acrylic acid ester having an alicyclic structure and a bifunctional (meth) acrylic acid ester. The curable resin composition may further contain a photopolymerization initiator as the component (D). Further, the present invention is a cured product obtained by curing the above-mentioned curable resin composition.

According to the present invention, it is possible to provide an optical lens prism having excellent optical properties such as low color dispersion and high light transmittance, a reactive (meth) acrylate group excellent in photo-curability in the side chain, low absorption, workability, Soluble multifunctional (meth) acrylic acid ester copolymer having improved optical characteristics and adhesiveness to an inorganic material under stiff yarn operating conditions such as wet heat conditions, can be produced with high efficiency. By curing the soluble polyfunctional (meth) acrylic acid ester copolymer of the present invention, it becomes an excellent resin as an optical lens / prism material. It is also possible to provide a curable resin composition having excellent optical properties such as low color dispersion and high light transmittance, heat resistance, hardness and processability, and improved heat resisting property in the form of a molded article under severe mounting conditions such as reflow conditions and cured products thereof .

Hereinafter, the soluble polyfunctional (meth) acrylic acid ester copolymer of the present invention and its production method will be described in detail. This soluble polyfunctional (meth) acrylic acid ester copolymer has an alicyclic structure and a hydroxyl group. Hereinafter, this soluble polyfunctional (meth) acrylic acid ester copolymer is abbreviated as a copolymer.

The copolymer of the present invention comprises a monofunctional (meth) acrylate ester (a) having an alicyclic structure, a monofunctional (meth) acrylate ester (b) having an alcoholic hydroxyl group and a bifunctional (meth) (Meth) acrylate (c) derived from a bifunctional (meth) acrylic acid ester (c) is added to the side chain in the presence of a monomer and 2,4-diphenyl- (Meth) acrylic acid ester copolymer having a structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d) at the terminal thereof. The term "soluble" as used herein means soluble in toluene, xylene, tetrahydrofuran, dichloroethane or chloroform. The availability test is performed under the conditions described below.

Since the copolymer is obtained by copolymerization of a monofunctional (meth) acrylic acid ester and a bifunctional (meth) acrylic acid ester, the copolymer has a branched structure or a crosslinked structure, and the abundance of such a structure is limited to the extent that it exhibits solubility. (Meth) acrylate (c1) derived from a bifunctional (meth) acrylic acid ester (c) in the side chain. The unreacted (meth) acrylic group is also referred to as a pendant (meth) acrylic group. Since the unreacted (meth) acrylic group exhibits polymerizability, it can be polymerized by further polymerization to provide a resin-insoluble cured resin.

The copolymer also has a structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d) at the terminal. By introducing the structural unit at the end of the copolymer, a cured product having improved moldability such as releasability can be obtained.

The copolymer may be a copolymer of a structural unit derived from a monofunctional (meth) acrylate ester (a) having an alicyclic structure, a unit derived from a monofunctional (meth) acrylate ester (b) having an alcoholic hydroxyl group, a bifunctional (meth) (c), and a structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d). In the structural unit derived from the bifunctional (meth) acrylic acid ester (c), both of the polymerizable double bonds (referred to as vinyl groups) contained in the two (meth) acrylic acid ester groups are involved in the polymerization, A structural unit (c2) for forming a vinyl group, and a structural unit (c1) containing an unreacted (meth) acrylic group which is involved in one vinyl group only polymerization and the other vinyl group remains unreacted. 2,4-diphenyl-4-methyl-1-pentene (d) acts as a chain transfer agent to prevent an increase in molecular weight and is present at the end of the copolymer.

The introduction amount of 2,4-diphenyl-4-methyl-1-pentene (d) into the copolymer is preferably from 0.02 to 0.35, preferably from 0.03 to 0.30, as a mole fraction (M _d ) Particularly preferably 0.05 to 0.15.

Herein, (a), (b), (c) and (d) are structural units derived from a monofunctional (meth) acrylate ester (a) having an alicyclic structure, monofunctional (meth) acrylates having an alcoholic hydroxyl group the number of moles of the structural unit derived from the bifunctional (meth) acrylic acid ester (c) and the structural unit derived from the 2,4-diphenyl-4-methyl-1-pentene (d) Mole fraction). By introducing the structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d) into the above range at the end of the copolymer, the releasability and low water absorbability can be improved.

The bifunctional (meth) acrylic acid ester (c) plays an important role as a crosslinking component for producing a pendant vinyl group by branching or crosslinking the copolymer, giving the copolymer curability and exhibiting heat resistance at the time of curing .

Examples of the bifunctional (meth) acrylic esters include cyclohexanedimethanol diacrylate, dimethyloltricyclodecane diacrylate, cyclohexanedimethanol dimethacrylate, dimethyloltricyclodecane dimethacrylate, ethylene glycol diacrylate, Propylene glycol diacrylate, 1,4-butanediol diacrylate, hexanediol diacrylate, diethylene glycol diacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, 1,4-butanediol dimethacrylate, (Meth) acrylic acid esters such as hexanediol dimethacrylate, diethylene glycol dimethacrylate and the like can be used, but are not limited thereto.

As preferred specific examples of the bifunctional (meth) acrylic acid ester, cyclohexanedimethanol diacrylate or dimethyloltricyclodecane diacrylate is preferably used in view of cost, ease of polymerization control, and heat resistance of the obtained polymer.

The copolymer has a structural unit (c1) containing a reactive (meth) acrylate group derived from a bifunctional (meth) acrylic acid ester (c) in its side chain. The structural unit (c1) represented by the formula (2) The molar fraction (M _c1 ) is preferably 0.05 to 0.5, and more preferably 0.1 to 0.3.

(C1) in the formula represents the number of moles of the structural unit (c1) containing a (meth) acrylate group. By satisfying the molar fraction, the curing property in light and heat is abundant, and a molded article having excellent heat resistance and mechanical properties after curing can be obtained.

The monofunctional (meth) acrylic acid ester (a) having an alicyclic structure is important for improving the solvent solubility, low absorptivity, heat resistance, optical characteristics and processability of the copolymer. Examples of the monofunctional (meth) acrylic acid ester having an alicyclic structure include isobonyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate Having at least one alicyclic structure selected from the group consisting of dicyclopentanyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl methacrylate, (Meth) acrylic acid esters, but are not limited thereto. Since the structural units derived from these components are introduced into the copolymer having an alicyclic structure, gelation of the polymer can be prevented to increase the solubility in the solvent, and optical properties such as low color dispersibility of the copolymer, Can be improved.

Specific preferred examples include isobornyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxy, and the like in view of cost, Having at least one alicyclic structure selected from the group consisting of ethyl acrylate, dicyclopentanyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl methacrylate, And monofunctional (meth) acrylic acid esters.

The monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group is important for improving the adhesion with an inorganic material under severe working conditions such as a wet heat condition of the copolymer. Examples of the monofunctional (meth) acrylic acid ester having an alcoholic hydroxyl group include 2-hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate and partially ethoxylated 2-hydroxy methacrylate, Is 2-hydroxyethyl methacrylate. These (meth) acrylic acid ester monomers having alcoholic hydroxyl groups may be used alone or in combination of two or more.

The monofunctional (meth) acrylic acid ester (b) containing an alcoholic hydroxyl group is a monofunctional (meth) acrylic acid ester (c) containing an alcoholic hydroxyl group and a molar fraction of the component (a), component ) it may be a structure mole fraction (M _b) of units derived from the formula (3) M _b is 0.05 or more, 0.60 or less, which is calculated by, preferably from 0.1 to 0.3.

_{M b = (b) / [} (a) + (b) + (c)] (3)

(A), (b) and (c) in the formula have the same meanings as in the formula (1).

By satisfying the molar fraction, it is possible to obtain a copolymer having good balance of optical characteristics under adverse yarn operating conditions such as wet heat conditions and adhesion properties with inorganic materials.

2,4-diphenyl-4-methyl-1-pentene (c) functions as a chain transfer agent and controls the molecular weight of the copolymer. The weight average molecular weight (Mw) of the copolymer of the present invention is in the range of 2000 to 20000, preferably 3000 to 10000. By using a copolymer having a relatively low molecular weight, the moldability and releasability of the resin composition or the cured product are enhanced.

Further, as a component (e) for the purpose of improving solubility and processability of the copolymer, it is possible to add a monofunctional (meth) acrylic acid ester having no alicyclic structure and hydroxyl group. Examples of such (meth) acrylic esters include methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-methylhexyl acrylate, 2-ethylhexyl acrylate, But is preferably methyl methacrylate or n-butyl acrylate. These (meth) acrylic acid ester monomers may be used alone or two or more of them may be used in combination, but at least one of (meth) acrylic acid esters selected from the group consisting of methyl methacrylate, methyl acrylate, n- Is most preferable.

The structural units derived from these other monomer components (e) are preferably at least 30 mol% based on the total amount of the structural units derived from the monomer component (a), the structural units derived from the monomer component (b) and the structural units derived from the monomer component (c) Is preferably within a range of less than 0.1.

(A) a monofunctional (meth) acrylate ester having an alicyclic structure, (b) a monofunctional (meth) acrylate ester having an alcoholic hydroxyl group, a bifunctional (meth) Acrylate ester (c) and 2,4-diphenyl-4-methyl-1-pentene (d), and therefore has a structural unit derived from each of them. (A), (b) to (d) show the following ranges when the number of moles of the structural units derived from the respective structural units is 100 mol, . (b) is 10 to 45 moles, (c) 10 to 50 moles, preferably 15 to 40 moles, (d) 2 to 35 moles, preferably 5 to 20 moles, mole.

The structural unit derived from the bifunctional (meth) acrylate ester (c) has a reactive (meth) acrylate group (c1). The molar number (c1) of the structural unit having the (meth) acrylate group When the unit is taken as 100 moles, it is preferably 5 to 35 moles, and preferably 10 to 25 moles. (C1) is preferably in the range of 1/4 to 3/4 of (c). If the amount of the component (c) or (c1) is too small, the heat resistance of the cured product is insufficient. If the component (c1) or c1 is too large, the moldability is deteriorated.

(A) a monofunctional (meth) acrylic acid ester having an alicyclic structure, (b) a monofunctional (meth) acrylic acid ester having an alcoholic hydroxyl group, 2 (C) and 2,4-diphenyl-4-methyl-1-pentene (d) are used, and the number of moles or molar fractions of the structural units derived from these monomers is in the range The usage amount is determined as much as possible. Although 2,4-diphenyl-4-methyl-1-pentene (d) is a known compound as a chain transfer agent, the amount of the 2,4-diphenyl-4-methyl-1-pentene used in the present invention is larger than that used as a chain transfer agent. The amount of 2,4-diphenyl-4-methyl-1-pentene (d) to be used is preferably in the range of 2, 4-diphenyl-4-methyl- The molar fraction of the structural units derived from pentene (d) is adjusted to be in the range of 0.02 to 0.35, which remains unreacted due to the low reactivity. Therefore, it is used in the range of 2 to 60 moles per 100 moles of the monomer, preferably in the range of 10 to 50 moles.

In the process for producing a soluble polyfunctional aromatic (meth) acrylic acid ester copolymer of the present invention, 2,4-diphenyl-4-methyl-1-pentene (d) is added to 100 parts by weight of a bifunctional (meth) acrylic acid ester (Meth) acrylic acid ester (a) having an alicyclic structure and 2 to 35 mol% of a monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group in an amount of 10 to 500 parts by weight, % And a bifunctional (meth) acrylic acid ester (c) in an amount of 96 to 10 mol% is polymerized at a temperature of 50 to 200 캜.

From the standpoint that 2,4-diphenyl-4-methyl-1-pentene (d) also functions as a chain transfer agent, the amount used is limited by the limitation of crosslinking reaction, the formation of pendant (meth) acrylate groups, Is preferably in the range of 10 to 500 parts by weight, more preferably in the range of 20 to 100 parts by weight, based on 100 parts by weight of the bifunctional (meth) acrylic acid ester (c). And most preferably in the range of 50 to 80 parts by weight.

The amount of the mono (meth) acrylic acid ester aromatic compound (a) having an alicyclic structure to be used is not particularly limited as long as the monofunctional (meth) acrylic ester (a) having an alicyclic structure, the monofunctional (meth) And the bifunctional (meth) acrylic acid ester (c) is 2 to 55 mol, preferably 10 to 40 mol, per 100 mol of the total. The amount of the bifunctional (meth) acrylic acid ester (c) used is from 96 to 10 mol, preferably from 20 to 50 mol%. The amount of the monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group is 2 to 50 mol%, preferably 10 to 40 mol%.

In the production process of the present invention, a radical polymerization initiator may be added when the initiation reaction rate due to the reaction in the decomposition is small. In this case, examples of the radical polymerization initiator used in the present invention include ketone peroxides such as cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide and methylcyclohexanone peroxide; Tert-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, n- Peroxyacetal such as butylperoxy) valerate; Hydroperoxides such as cumene hydroperoxide and 2,5-dimethylhexane-2,5-dihydroperoxide; Di (tert-butylperoxy) hexane, diisopropylbenzene peroxide, tert-butylperoxy (tert- butylperoxy) Dialkyl peroxides such as methylperoxide; Diacyl peroxides such as decanoyl peroxide, lauroyl peroxide, benzoyl peroxide and 2,4-dichlorobenzoyl peroxide; Peroxycarbonates such as bis (tert-butylcyclohexyl) peroxydicarbonate; butyl peroxybenzoate, and peroxy esters such as 2,5-dimethyl-2,5-di (benzoyl peroxy) hexane; and organic peroxide type polymerization initiators such as 2,2'-azobisisobutyronitrile Azo compounds such as 1,1-azobis (cyclohexane-1-carbonitrile), azocumene 2,2'-azobismethyl valeronitrile and 4,4'-azobis (4- And a polymerization initiator. The amount of these radical polymerization initiators to be used is not particularly limited, but is preferably 0.01 to 25 parts by weight, more preferably 0.05 to 20 parts by weight, based on 100 parts by weight of the total amount of the monomer components. And most preferably in the range of 0.1 to 15 parts by weight.

The polymerization reaction can be carried out basically by bulk polymerization without using a solvent, but it can also be carried out in one or more organic solvents which dissolve the resulting soluble polyfunctional (meth) acrylic acid ester aromatic copolymer. As the organic solvent, a compound which does not substantially inhibit radical polymerization can be used without any particular limitation as far as it forms a homogeneous solution by dissolving the chain transfer agent, the initiator, the monomer and the polyfunctional (meth) acrylic acid ester aromatic copolymer of the present invention.

Examples of the organic solvent usable herein include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, propylbenzene and butylbenzene; Straight chain aliphatic hydrocarbons such as ethane, propane, butane, pentane, hexane, heptane, octane, nonane and decane; Branched aliphatic hydrocarbons such as 2-methylpropane, 2-methylbutane, 2,3,3-trimethylpentane and 2,2,5-trimethylhexane; Cyclic aliphatic hydrocarbons such as cyclohexane, methylcyclohexane and ethylcyclohexane; And paraffin oil obtained by purifying a petroleum distillate by hydrogenation. Of these, toluene, xylene, pentane, hexane, heptane, octane, 2-methylpropane, 2-methylbutane, cyclohexane, methylcyclohexane and ethylcyclohexane are preferred. Toluene, xylene, methylcyclohexane and ethylcyclohexane are more preferable from the viewpoint of balance of polymerizability and solubility and ease of availability.

These organic solvents may be used alone or in combination of two or more. The amount of the solvent to be used is not particularly limited.

In the production process of the present invention, the polymerization is carried out in a temperature range of 50 to 200 캜. If the polymerization reaction is carried out at less than 50 ° C, the polymerization rate is lowered, which is not preferable from the viewpoint of industrial practice. When the temperature exceeds 200 ° C, the selectivity of the reaction is lowered and the reaction is difficult to control. It is not preferable because it becomes easy.

The method for recovering the copolymer after the termination of the polymerization reaction is not particularly limited. For example, a commonly used method such as a thermal decompression dehydration method, a steam stripping method, a precipitation with a poor solvent do.

The soluble polyfunctional (meth) acrylic acid ester copolymer of the present invention or the soluble polyfunctional (meth) acrylic acid ester copolymer obtained by the production method of the present invention can be processed into a molding material, a sheet or a film. A cured product is obtained by curing this by heating or the like. Soluble polyfunctional (meth) acrylic acid ester copolymer, a molded product obtained by molding the same into a molding material, a sheet or a film, or a cured resin or a molded product obtained by curing the molded product, a sheet or a film thereof can satisfy the characteristics of low color dispersion, low dielectric constant, low water absorption, An antistatic agent, an antioxidant, an anti-fogging agent, an anti-rust agent, a flame retardant, a medicinal material, a coagulant, an antioxidant, an antioxidant, , A solid fuel binder, a conductive treatment agent, and the like. Examples of optical parts include a CD pickup lens, a DVD pickup lens, a Fax lens, a LBP lens, a polygon mirror, and a prism.

The soluble polyfunctional (meth) acrylic acid ester copolymer of the present invention is soluble in at least one solvent selected from toluene, xylene, THF, dichloroethane, dichloromethane and chloroform. It is preferably soluble in all of the solvents. The term "soluble" as used herein means that 1 g or more is dissolved in 100 ml of a solvent at room temperature (25 ° C.). It is preferable that no gel is formed after dissolution.

Next, the curable resin composition of the present invention will be described in detail. Since the curable resin composition of the present invention contains the component (A), the component (B) and the component (C) as essential components, the essential components will be described.

Soluble polyfunctional (meth) acrylic acid ester copolymer (hereinafter abbreviated as a copolymer) which is a component (A) of the present invention is the above soluble polyfunctional (meth) acrylic acid ester copolymer of the present invention.

(Meth) acrylate monomer (hereinafter, abbreviated as a (meth) acrylate monomer) having at least one functional group having an unsaturated double bond is used as the component (B). (Meth) acrylate monomers are those having at least one (meth) acryloyl group in the molecule, and one or more of them are used. The (meth) acrylate used as the component (B) can be used in combination with the component (A) to adjust the viscosity of the composition without deteriorating the curability and at the same time synergistically exhibits low color dispersion, high light transmittance The same optical characteristics are simultaneously improved.

The (meth) acrylate monomer is a monomer having a molecular weight of 1000 or less, and may be a monomer having a molecular weight distribution such as polyethylene glycol di (meth) acrylate. In this case, Mw is 1000 or less. Advantageously, it is a monomer comprising a compound having no molecular weight distribution or a mixture thereof.

As the (meth) acrylate monomer, for example, a monofunctional (meth) acrylic acid ester (a) having an alicyclic structure is preferably used in copolymerization with the component (A) (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (Meth) acrylate, cyclohexane-1,4-dimethanol mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, phenylpolyethoxy (Meth) acrylate, o-phenylphenol polyethoxy (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, )acryl (Meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (Meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tricyclodecanedimethanol (Meth) acrylate, bisphenol A polyethoxydi (meth) acrylate, bisphenol A polypropoxydi (meth) acrylate, bisphenol F polyethoxydi (meth) acrylate, ethylene glycol di (meth) acrylate, trimethylolpropane Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol (meth) acrylate, (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, polyethylene glycol di (meth) (Meth) acrylate of hydroxypivalic acid neopentyl glycol, hydroxypivalic acid di (meth) acrylate, tripentaerythritol hexa (meth) acrylate, tripentaerythritol penta (meth) acrylate, Di (meth) acrylate of caprolactone adduct (for example, KAYARAD HX-220 and HX-620 manufactured by Nippon Kayaku Co., Ltd.), trimethylolpropane tri (meth) acrylate, trimethylolpropane polyethoxy tri (Meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, and the like. Particularly preferable examples include 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate and pentaerythritol tri (meth) have.

Next, the component (C) will be described.

The fine silica particles (d) having an average particle diameter of 1 to 100 nm used as the component (C) of the present invention are not particularly limited as long as they are metal oxides containing silicon and have an average particle diameter in the range of 1 to 100 nm. As the silica fine particles, there can be used fine particles of dried silica in powder form, and colloidal silica (silica sol) dispersed in an organic solvent. From the viewpoint of dispersibility, it is preferable to use colloidal silica (silica sol) dispersed in an organic solvent. As the organic solvent in the case of using colloidal silica (silica sol) dispersed in an organic solvent, it is preferable to use one in which the organic component used in the resin composition is dissolved, and examples thereof include alcohols, ketones, esters, glycol ethers . Colloidal silica dispersed in an alcohol-based solvent such as methanol, ethanol, isopropyl alcohol, butyl alcohol or n-propyl alcohol, or in a ketone-based organic solvent such as methyl ethyl ketone or methyl isobutyl ketone in view of ease of desolvation, silica It is preferable to use a sol and silica fine particles, more preferably colloidal silica dispersed in isopropyl alcohol. Particularly, when colloidal silica dispersed in isopropyl alcohol is used, the viscosity after desolvation is lower than that of other solvent systems, so that it is suitable to stably produce a resin composition having a low viscosity. The colloidal silica (silica sol) and silica fine particles dispersed in these organic solvents may be surface-treated with a coupling agent such as a silane coupling agent or a titanate-based coupling agent to the extent that the required characteristics are not adversely affected, A dispersant such as a surfactant may be used.

The average particle diameter of the fine silica particles is preferably from 1 to 100 nm, more preferably from 1 to 50 nm, still more preferably from 5 to 50 nm, and most preferably from 5 to 40 nm from the viewpoint of balance of transparency and fluidity. If it is less than 1 nm, the viscosity of the prepared resin composition is extremely increased, so that the filling amount of the fine silica particles is limited and the dispersibility is deteriorated, so that sufficient transparency and a coefficient of linear expansion can not be obtained. Further, if it exceeds 100 nm, transparency may remarkably deteriorate.

Here, the average particle diameter of the silica fine particles is calculated from the specific surface area S (m 2 / g) determined by the nitrogen adsorption method (BET method) to D (nm) = 2720 / S.

It is preferable to use silica fine particles having a primary particle size of not less than 200 nm in a proportion of not more than 5% in order not to lower the light transmittance at a wavelength of 400 to 500 nm, more preferably 0%. Silica fine particles having different average particle diameters may be mixed and used in order to increase the filling amount of the silica fine particles. As the silica fine particles, a porous silica sol or a composite metal oxide of aluminum, magnesium, zinc or the like, as shown in Japanese Patent Laid-Open No. 7-48117, may be used.

The content of the fine silica particles in the curable resin composition is preferably from 15 to 90 wt%, more preferably from 25 to 80 wt%, more preferably from 25 to 70 wt%, and most preferably from 30 to 70 wt%, from the viewpoint of balance of the linear expansion coefficient and lighter weight. 70 wt%. Within this range, since the fluidity and dispersibility are good, a molded article having a sufficient strength and a low linear expansion coefficient can be produced easily.

The curable resin composition of the present invention contains the above components (A), (B) and (C) as essential components, and the content ratio thereof is preferably within the following range. Wherein the amount of the component (A) is 2 to 83 wt%, the amount of the component (B) is 83 to 2 wt%, the amount of the component (C) is 15 to 30 wt% 90 wt%. More preferably, the blending amount of the component (A) is from 5 to 75 wt%, the blending amount of the component (B) is from 80 to 10 wt%, and the blending amount of the component (C) is from 15 to 80 wt%. Most preferably, the blending amount of the component (A) is 10 to 65 wt%, the blending amount of the component (B) is 75 to 15 wt%, and the blending amount of the component (C) is 15 to 70 wt%.

The curable resin composition of the present invention preferably contains a polymerization initiator, preferably a photopolymerization initiator, as the component (D). The curable resin composition of the present invention can be molded and cured even when it is thermally polymerized. However, when an optical material such as a lens is molded and cured, photo-curing which is strictly controllable is advantageous, and therefore, it is preferable to add a photopolymerization initiator .

Examples of the photopolymerization initiator used as the component (D) include benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether and benzoin isobutyl ether; Acetophenone, 2,2-diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 2-hydroxy- Acetophenones such as diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one; Anthraquinones such as 2-ethyl anthraquinone, 2-tertiarybutylanthraquinone, 2-chloro anthraquinone, and 2-amylanthraquinone; Thioxanthones such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone and 2-chlorothioxanthone; Ketal such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Benzophenones such as benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide and 4,4'-bismethylaminobenzophenone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide.

These may be used alone or as a mixture of two or more kinds. Further, tertiary amines such as triethanolamine and methyldiethanolamine, N, N-dimethylaminobenzoic acid ethyl ester and N, N-dimethylaminobenzoic acid isoamyl ester Benzoic acid derivatives, and the like.

Examples of the thermal polymerization initiator used as the component (D) include ketone peroxides such as cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide and methylcyclohexanone peroxide; Tert-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, n- Peroxyacetal such as butylperoxy) valerate; Hydroperoxides such as cumene hydroperoxide and 2,5-dimethylhexane-2,5-dihydroperoxide; Di (tert-butylperoxy) hexane, diisopropylbenzene peroxide, tert-butylperoxy (tert- butylperoxy) Dialkyl peroxides such as methylperoxide; Diacyl peroxides such as decanoyl peroxide, lauroyl peroxide, benzoyl peroxide and 2,4-dichlorobenzoyl peroxide; Peroxycarbonates such as bis (tert-butylcyclohexyl) peroxydicarbonate; butyl peroxybenzoate, and peroxy esters such as 2,5-dimethyl-2,5-di (benzoyl peroxy) hexane; and organic peroxide type polymerization initiators such as 2,2'-azobisisobutyronitrile Azo compounds such as 1,1-azobis (cyclohexane-1-carbonitrile), azocumene 2,2'-azobismethyl valeronitrile and 4,4'-azobis (4- And a polymerization initiator.

The amount of these polymerization initiators to be used is not particularly limited, but is preferably 0.01 to 25 parts by weight, more preferably 0.05 to 20 parts by weight, based on 100 parts by weight of the total amount of the polymerizable components including the component (A) Do. And most preferably in the range of 0.1 to 15 parts by weight.

When the curable resin composition of the present invention contains the component (A), the component (B), the component (C) and the component (D), the preferable content is as follows. The blending amount of the component (B) is 5 to 250 parts by weight, preferably 20 to 100 parts by weight, per 100 parts by weight of the component (A). The amount of the component (C) is 0.1 to 10 parts by weight, preferably 1.0 to 5 parts by weight based on 100 parts by weight of the total of the components (B) and (A).

In another aspect, the curable resin composition preferably contains 0.1 to 10 wt% of component (D) relative to 100 wt% of the total of components (A), (B) and (D). (D) is in the above-described range with respect to the total of the component (A), the component (B) and the component (D), the moldability, heat resistance and optical properties Is improved. If the amount of the component (D) is too small, the insufficient curing tends to occur and the heat resistance and light resistance decrease. If too much, the mechanical strength decreases and the heat resistance deteriorates. When an organic solvent and a filler are contained in the curable resin composition, the above content is calculated except for these contents.

In the curable resin composition of the present invention, a polymerization inhibitor may be added for the purpose of preventing the viscosity from rising due to the progress of the polymerization reaction during the production of the resin composition. In the curable resin composition of the present invention, a hydrophobic treatment agent such as trimethylmethoxysilane, hexamethyldisilazane, trimethylchlorosilane, or octamethylcyclotetrasiloxane may be contained for the purpose of reducing the water absorption rate.

Thermoplastic or thermosetting oligomers or polymers can be used in combination in the curable resin composition of the present invention as far as the properties such as transparency, solvent resistance, liquid-crystal qualities, and heat resistance are not impaired. In this case, it is preferable to use an oligomer or polymer having an alicyclic structure or a cardo structure, which also serves to reduce the absorbency or reduce the linear expansion coefficient.

The curable resin composition of the present invention may contain a small amount of a filler such as an antioxidant, an ultraviolet absorber, a salt pigment or other inorganic filler in a range that does not impair characteristics such as transparency, solvent resistance, do.

Examples of the method for producing the curable resin composition of the present invention include a method in which an organic solvent is removed by mixing colloidal silica (silica sol) dispersed in an organic solvent with other compounds and, if necessary, A method in which colloidal silica (silica sol) dispersed in a solvent and other compounds are mixed, desolvated if necessary, cast and desolvated, and a method of dispersing powdery silica fine particles dried by using a high- And the like. Examples of the apparatus having high dispersing ability include a fill mix and a variety of beads mills manufactured by Tokushu Kika Kogyo Co., Ltd. When using a device having high dispersing ability, care must be taken not to excessively increase the temperature so that the reaction does not proceed rapidly during mixing or kneading. The temperature of the composition at the time of preparing the curable resin composition is preferably maintained at 30 to 100 占 폚, more preferably 35 to 70 占 폚, and most preferably 35 to 60 占 폚 in view of the balance with the desolvation speed. If the temperature is excessively increased, the fluidity is extremely lowered or becomes gel-like and the sheet can not be formed. When a device having a high dispersing ability is used, it is necessary to pay attention to mixing of impurities due to abrasion of the device or the like. When colloidal silica dispersed in an organic solvent is used, the organic solvent may be left in the curable resin composition. When an organic solvent is contained, a post-treatment step such as heat treatment is provided, and finally the organic solvent is desorbed from a coating layer composed of the curable resin composition of the present invention in the form of an optical film and a sheet. The content of the organic solvent in the curable resin composition is preferably from 0 to 10 wt% of the curable resin composition in order to avoid problems such as foaming, wrinkling or coloring of the sheet in the process of removing volatile components by a crosslinking step or a heat treatment, , More preferably 0 to 5 wt%, and most preferably 0 to 3 wt%.

The curable resin composition of the present invention can obtain a cured product by irradiating active energy rays such as ultraviolet rays. Specific examples of the light source used in the case of curing by irradiation with an active energy ray include fluorescent lamps for ultraviolet rays, high pressure mercury lamps for copying, medium pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, A lamp, a metal halide lamp, or an electron beam by a scanning type curtain type electron beam accelerating furnace. When the curable resin composition of the present invention is cured by ultraviolet irradiation, the amount of ultraviolet radiation required for curing may be about 300 to 20000 mJ / cm 2. In order to sufficiently cure the curable resin composition, it is preferable to irradiate active energy rays such as ultraviolet rays in an inert gas atmosphere such as nitrogen gas.

The curable resin composition of the present invention can also be heated to obtain a cured product. The curing temperature is preferably 70 to 200 占 폚. And more preferably 80 to 180 캜. The curing time is preferably 1 minute to 15 hours. More preferably 3 minutes to 10 hours.

In the case of heat treatment at a high temperature after curing by an active energy ray and / or cross-linking by thermal polymerization, for the purpose of reducing the linear expansion coefficient during the heat treatment step, It is preferable to include a heat treatment process for 24 hours.

The curable resin composition of the present invention may optionally contain additives such as a silane coupling agent, a polymerization inhibitor, a leveling agent, a surface lubricant, a defoamer, a light stabilizer, an antioxidant, a plasticizer, an antistatic agent and a filler.

The cured product of the curable resin composition of the present invention can be obtained by irradiating active energy rays such as ultraviolet rays or visible light laser in accordance with a conventional method. When ultraviolet rays are used, they are irradiated using a low-pressure or high-pressure mercury lamp, ultra-high-pressure mercury lamp, metal halide lamp, xenon or the like. Particularly, as the light source, a lamp having a high energy intensity at 350 to 450 nm is preferable.

The refractive index of the cured product of the curable resin composition of the present invention obtained by curing by active energy rays or heat such as ultraviolet rays is preferably 1.45 or more at 25 占 폚, and more preferably 1.48 or more at 25 占 폚. Particularly when the optical lens is made of the resin composition for an optical material of the present invention, when the refractive index of the cured product is less than 1.45 at 25 캜, there arises a problem that a sufficient lens module can not be made compact.

Further, the Abbe number of the cured product (numerical value inherent to the material that defines the property of changing the refractive index according to the wavelength of light) is preferably 40.0 or more, and more preferably 45.0 or more. If the Abbe's number of the cured product is less than 40.0, the chromatic aberration will be large and the blurring of color will occur, which is not preferable.

The composite cured product obtained by molding and curing the curable resin composition of the present invention is excellent as an optical material such as a lens or a prism. And is particularly useful as an optical plastic lens such as an aspherical lens, a fresnel lens, a lenticular lens, a spectacle lens, and a coating material or an optical adhesive material for an optical film. The optical lens obtained from the curable resin composition of the present invention is advantageously used in an imaging device. In addition, the curable resin composition or the composite cured product can be used for optoelectronics applications such as optical disc, optical fiber and optical waveguide, printing ink, paint, clear coating agent, gloss varnish and the like.

Further, the curable resin composition of the present invention can be used as an adhesive, and examples of articles having a cured product resulting from curing as an adhesive layer include cellular phones, portable game machines, digital cameras and the like.

When the polarizing film and the protective plate are bonded to each other using the curable resin composition of the present invention, it is not limited to a protective plate such as a non-alkali glass or quartz glass having excellent active energy ray transmittance. An acrylic plate, a polycarbonate May also be used because of the good reaction curability of the composition.

The curable resin composition of the present invention is applied to a base material such as a polarizing film by a coating apparatus such as a roll coater, a spin coater, or a screen printing method so as to have an adhesive film thickness of 1 to 100 m, And then cured by irradiation.

<Examples>

The following examples illustrate the invention, but the invention is not limited thereto. All parts in each example are parts by weight. In addition, the measurement of the softening temperature and the like in the examples was carried out by preparing and measuring samples by the following methods.

1) Molecular weight and molecular weight distribution of polymer

The molecular weight and molecular weight distribution of the copolymer were measured using GPC (Toso Co., HLC-8120GPC), solvent: tetrahydrofuran (THF), flow rate: 1.0 ml / min, and column temperature: 40 캜. The molecular weight of the copolymer was measured as polystyrene reduced molecular weight using a calibration curve with monodisperse polystyrene.

2) Structure and solubility test of polymer

NMR analysis and &lt; 1 &gt; H-NMR analysis using a JNM-LA600 type nuclear magnetic resonance spectrometer manufactured by Nihon Denshi Co., Chloroform-d1 was used as a solvent, and the resonance line of tetramethylsilane was used as an internal standard.

The solubility test was carried out by adding 1 g of a copolymer to 100 ml of various organic solvents (toluene, xylene, tetrahydrofuran, dichloroethane and chloroform) at 25 ° C and stirring for 30 minutes using a magnetic stirrer. Respectively. The solubility in all the above-mentioned organic solvents and the case where the generation of the gel was not recognized was defined as &amp; cir &amp;: Solubility.

3) Preparation and measurement of samples for glass transition temperature (Tg) and softening temperature measurement

The copolymer solution was uniformly applied to a glass substrate so that the thickness after drying was 20 占 퐉, and then heated at 90 占 폚 for 30 minutes using a hot plate and dried. The obtained resin film on the glass substrate was set on a TMA (thermomechanical analyzer) measuring apparatus together with the glass substrate, and the temperature was raised to 220 DEG C at a heating rate of 10 DEG C / min in a nitrogen stream, and further heat treatment was performed at 220 DEG C for 20 minutes The resin was cured. After the glass substrate was cooled to room temperature, the measurement was carried out by contacting the sample in a TMA measuring apparatus with an analytical probe and scanning the sample at 30 DEG C to 360 DEG C at a heating rate of 10 DEG C / min under a nitrogen gas stream. Respectively. When the probe does not penetrate the resin film and does not show a probe penetration amount smaller than the film thickness due to the heat resistance of the sample, the penetration amount with respect to the temperature at which the probe penetrated and the film thickness is expressed as a percentage in addition to the softening temperature.

4) Measurement of thermal weight loss and thermal discoloration

The thermal decomposition temperature and heat discoloration resistance of the copolymer were measured by setting the sample on a TGA (thermogravimetry) measuring apparatus and scanning the sample from 30 ° C. to 320 ° C. at a heating rate of 10 ° C./min under a nitrogen gas stream. And the amount of discoloration of the sample after the measurement was visually checked to evaluate heat discoloration resistance by classifying it as?: No heat discoloration,?: Pale yellow,?: Brown, and x: black.

5) Measurement of Absorption Rate

The weight of the test sample (cured sheet) vacuum-dried at 60 占 폚 for 24 hours was defined as Wo and weighed in a scale capable of measuring up to 占 0.1 mg and subjected to humidification for one week in a constant temperature and humidity chamber having a temperature of 85 占 폚 and a relative humidity of 85% Respectively. After humidifying, the wipes were wiped off the test sample, and the sample was weighed to a measurable scale up to ± 0.1 mg to make W. The absorption rate was calculated by the following formula (3). Three identical test samples were prepared and tested identically.

Wo / W x 100 = absorption rate (3)

6) Measurement of solvent resistance

The solvent resistance of the copolymer was measured by immersing the sample plate vacuum-press molded at 200 ° C for 1 hour in toluene at room temperature for 10 minutes and observing the change of the sample after immersion visually. The solvent resistance was evaluated by classification as expansion.

7) Measurement of refractive index

The synthesized soluble polyfunctional (meth) acrylic acid ester copolymer was dissolved in toluene, and 1.0 part by weight of perbutyl O as an initiator was added to 100 parts by weight of the soluble polyfunctional (meth) acrylic acid ester copolymer. A cast sheet was prepared from the polymer solution, and the cast sheet was crushed and pelletized, filled in a press mold, and cured at 170 DEG C for 1 hour by a press molding machine. The refractive index of the d-line (587.6 nm) was measured with KPR-200 (manufactured by Shimadzu Kalnew) using the obtained cured parallel plate as a test piece. Immediately after molding, the measurement timing was set at a high temperature and a high humidity of a mild condition of 85 캜 85 RH for one week.

8) Adhesion test

The varnish diluted with the solvent (methyl ethyl ketone) was coated on the glass substrate and dried at 80 DEG C for 5 minutes, and then cured in an inert oven at 200 DEG C for 1 hour under a nitrogen stream . Next, the glass substrate on which the cured coated film of the copolymer was placed was subjected to elevation improvement of 11 vertically and horizontally at intervals of 1 mm on the surface of the coating film according to JIS K 5400 to make 100 checkerboard scales. After the cellophane tape was brought into close contact with the surface of the cellophane tape, the number of remaining grid grids that were not peeled off at the time of peeling was counted.

9) Preparation of Test Piece for Measuring Physical Properties of Curable Resin Composition

The curable composition was injected into a glass frame having a width of 50 mm, a length of 50 mm, and a thickness of 1.0 mm between two glass plates with a gap of 0.2 to 1.0 mm and the outer periphery was wrapped with a polyimide tape and fixed. 1) The above-described high-pressure mercury lamp was irradiated with ultraviolet rays for 5 seconds, or (2) the glass mold was placed in an inert gas oven under a nitrogen gas stream and heated at 180 DEG C for 1 hour to cure. The resin plate cured from the glass frame was demolded and used for various properties.

10) Measurement of refractive index

The refractive index and the Abbe number at 589 nm were measured with Abbe's refractometer (manufactured by Atago Co.).

11) Color (YI)

A flat plate having a thickness of 1.0 mm was measured with a colorimeter (trade name: MODEL TC-8600, manufactured by Tokyo Denshoku Co., Ltd.) and the YI value thereof was shown.

12) Haze (turbidity) and total light transmittance

A test piece having a thickness of 0.2 mm was prepared, and the haze (turbidity) and the total light transmittance of the sample were measured using an integrated light transmittance measuring apparatus (SZ-Σ90, manufactured by Nippon Denshoku Co., Ltd.).

13) Dissimilarity: The hardened resin was evaluated according to the degree of difficulty when releasing it from the mold.

○ ... Good mold releasability

△ ... Dissimilarity is somewhat difficult

× ... Difficulty releasing or having residual frame

14) Frame Reproducibility: The surface shape of the cured resin layer and the surface shape of the mold were observed.

○ ... Good reproducibility

△ ... Reproducibility is good depending on the curing conditions (light, heat)

× ... Poor reproducibility

15) Burr, Leakage: When the cured resin was released from the mold, it was evaluated according to the size of the bur formed outside the product portion of the molded product and the degree of leakage of the resin to the clearance of the mold.

○ ... The amount of burrs generated is less than 0.05 mm, and the leakage of the resin into the frame clearance is less than 1.0 mm.

△ ... The yield of burr is 0.05mm or more and less than 0.2mm. Leakage of the resin in the clearance of the frame is not less than 1.0 mm and less than 3.0 mm.

× ... The burr formation amount is 0.2 mm or more, and the leaking amount of the resin to the frame clearance is 3.0 mm or more.

16) Reflow heat resistance: A 1-mm-thick parallel plate was used as a test piece, and a spectral transmittance of 400 nm was measured with a spectroscopic colorimeter CM-3700d (manufactured by Konica Minolta). The measurement timing was made before the heat-resistant test in which post-curing was performed at 190 占 폚 for 60 minutes and after the heat resistance test at 260 占 폚 for 8 minutes in an air oven.

17) Heat Resistance (Resistance)

A sample obtained by bonding an alkali-free glass (thickness: 0.7 mm) and an acrylic plate having a thickness of 2 mm to a thickness of 25 탆 at an energy of 3000 mJ using an ultrahigh-pressure mercury lamp of 157 mW was irradiated for 30 minutes at -35 캜 for 30 minutes, Minute, the peeling state of the two substrates was observed, and it was evaluated as &quot; No peeling &quot;, and &quot; Peeling &quot;

18) Moisture resistance

A sample in which an alkali glass (thickness: 0.7 mm) and an acrylic plate having a thickness of 2 mm were adhered with a thickness of 25 탆 at an energy of 3000 mJ using an ultrahigh-pressure mercury lamp of 157 mW was left at 60 캜 and 90% RH for 100 hours, The state of peeling of the substrate was observed, and it was evaluated as &amp; cir &amp;

19) Shape maintenance Heat resistance

(Shape 1) of the spherical lens of the composite cured layer subjected to post curing and the surface shape (Shape 2) of the spherical lens of the composite cured layer after passing through the solder reflow furnace at 280 ° C three times, Contact type three-dimensional shape measuring device manufactured by Mitaka Kouki Co., Ltd., and the maximum value of the difference between the shape 1 and the shape 2 was calculated as shape maintaining heat resistance.

(Example 1)

3.2 mol (926.5 mL) of dimethyloltricyclodecane diacrylate, 8.0 mol (1814.1 mL) of isobornyl methacrylate, 4.8 mol (645.5 mL) of 2-hydroxypropyl methacrylate, -Methyl-1-pentene and 2,400 ml of toluene were charged into a 10.0 L reactor, and 240 mmol of benzoyl peroxide was added thereto at 90 DEG C and reacted for 6 hours. After the polymerization reaction was stopped by cooling, the reaction mixture was poured into a large amount of hexane at room temperature to precipitate a polymer. The obtained polymer was washed with hexane, filtered, dried and weighed to obtain 1392.6 g of copolymer A (yield: 40.5 wt%).

The copolymer A obtained had Mw of 8950, Mn of 3470 and Mw / Mn of 2.58. ¹³ C-NMR, ¹ H-NMR analysis and elemental analysis showed that the copolymer A had a total of 18.2 mol% of structural units derived from dimethylol tricyclodecane diacrylate and a total of 51.1 And 30.7 mol% of a structural unit derived from 2-hydroxypropyl methacrylate. The terminal group of the structure derived from 2,4-diphenyl-4-methyl-1-pentene is dimethyloltricyclodecane diacrylate, isobornyl methacrylate, 2-hydroxypropyl methacrylate, Diphenyl-4-methyl-1-pentene was present in an amount of 8.3 mol%.

Copolymer A was soluble in toluene, xylene, THF, dichloroethane, dichloromethane and chloroform, and no gel formation was observed. Also, the cast film of Copolymer A was a clear film without turbidity.

The copolymer A was made into a cured sheet under various measurement conditions. The cured sheet was cut and the optical characteristics, the water absorption rate, the decrease in heat weight, the heat discoloration resistance and the solvent resistance were measured.

As a result, the coefficient of linear expansion was 91 ppm / 캜, the water absorption rate was 0.98%, and the solvent resistance was ◯.

As a result of TMA measurement, the softening temperature was 300 ° C or more. As a result of TGA measurement, the weight loss at 300 캜 was 1.8 wt% and the heat discoloration was ◎.

As a result of measuring the refractive index of the copolymer A, the refractive index after curing (589 nm) was 1.520 and the refractive index after moist heat testing (589 nm) was 1.514.

In addition, it was confirmed that the number of remaining mass scales in the adhesion test was counted, and 100 mass scales remained on the substrate.

(Examples 2 to 13 and Comparative Examples 1 to 6)

Various bifunctional acrylates and monofunctional (meth) acrylates were polymerized in the same manner as in Example 1 with the raw material compositions shown in Table 1.

The amounts of the raw materials used in the reaction are shown in Tables 1 and 2, and the test results of the copolymer and its cured product are shown in Tables 3 and 4. Other reaction conditions and measurement conditions are the same as in Example 1, unless otherwise specified. In Table 1, the amount of raw materials to be used is expressed in terms of mol and weight (g), and the form of the substrate is mol / g.

The abbreviations used in the table are shown below.

DMTCD: dimethyloltricyclodecane diacrylate (c)

BDDA: 1,4-butanediol diacrylate (c)

HOP: 2-hydroxypropyl methacrylate (b)

HO: 2-hydroxyethyl methacrylate (b)

CD570: partial ethoxylated 2-hydroxyethyl methacrylate (b)

IBOMA: isobornyl methacrylate (a)

DCPM: dicyclopentanyl methacrylate (a)

DCPA: dicyclopentanyl acrylate (a)

? MSD: 2,4-diphenyl-4-methyl-1-pentene (d)

DDME: n-dodecyl mercaptan

MMA: methyl methacrylate

DCP-A; Tricyclodecane dimethanol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)

M-600A; 2-hydroxy-3-phenoxypropyl acrylate (epoxy ester M-600A manufactured by Kyoeisha Chemical Co., Ltd.)

3EG-A; Triethylene glycol diacrylate (light acrylate 3EG-A: manufactured by Kyoeisha Chemical Co., Ltd.)

FA-513AS; Dicyclopentanyl acrylate (manufactured by Hitachi Kasei Kogyo K.K.)

FA-129AS; Nonanedioldiacrylate (manufactured by Hitachi Kasei Kogyo K.K.)

SR205; Triethylene glycol dimethacrylate (Sartomer-SR205: manufactured by Sartomer)

EG; Ethylene glycol dimethacrylate (Light Ester EG; manufactured by Kyoeisha Chemical Co., Ltd.)

MEK-SD; Methyl ethyl ketone dispersion type colloidal silica (silica content: 30% by weight, average particle diameter: 10 to 20 nm, Snowtex MEK-SD- (1), manufactured by Nissan Kagaku K.K.)

MEK-ST-MS; (MEK solvent, Snowtex MEK-ST-MS, manufactured by Nissan Kagaku Kogyo Co., Ltd.) dispersed in methyl ethyl ketone (silica content 35 wt%, average particle diameter 17-23 nm)

MEK-ST-L; (MEK solvent, Snowtex MEK-ST-L, manufactured by Nissan Kagaku K.K.) having a silica content of 30 wt% and an average particle size of 40 to 50 nm were dispersed in methyl ethyl ketone dispersion type colloidal silica

SC1050; Methyl ethyl ketone dispersion type colloidal silica (average particle diameter 0.2 to 0.3 mu m, MEK solvent, silica content 65 wt%, SC1050-MMA, manufactured by ADMATECHS)

AO-60; Antioxidant (Adekastab AO-60, manufactured by Adeka Co., Ltd.)

Per butyl O; butyl peroxy-2-ethyl hexanate (manufactured by Nippon Oil Co., Ltd.)

Irgacure 184; 1-Hydroxy-cyclohexyl-phenyl-ketone (available from Chiba Specialty Chemicals Co.)

In Table 4, G indicates gelling. In Tables 4 and 8, NM indicates that measurement is impossible. In the gel production of Tables 3 to 6, &quot; o &quot;

(Synthesis Example 1)

Copolymer A was obtained in the same manner as in Example 1.

(Synthesis Example 2)

4.8 mol (950.4 g) of 1,4-butanediol diacrylate, 6.4 mol (922.7 g) of dicyclopentyl methacrylate, 4.8 mol (692.2 g) of 2-hydroxypropyl methacrylate, 4.8 mols (1135 g) of 4-methyl-1-pentene and 2400 ml of toluene were charged into a 10.0 L reactor, 240 mmol of benzoyl peroxide was added at 90 DEG C and reacted for 6 hours. After the polymerization reaction was stopped by cooling, the reaction mixture was poured into a large amount of hexane at room temperature to precipitate a polymer. The obtained polymer was washed with hexane, filtered, dried and weighed to obtain Copolymer B.

The Mw of the obtained copolymer B was 12500, the Mn was 3640, and the Mw / Mn was 3.43. By conducting ¹³ C-NMR, ¹ H-NMR analysis and elemental analysis, the copolymer B had a total of 27.8 mol% of the structural units derived from 1,4-butanediol diacrylate and the structural units derived from dicyclopentanyl methacrylate as the total 27.8 mol%, and 41.6 mol% of the structural unit derived from 2-hydroxypropyl methacrylate. Also, the terminal group of the structure derived from 2,4-diphenyl-4-methyl-1-pentene is preferably 1,4-butanediol diacrylate, dicyclopentanyl methacrylate, 2-hydroxypropyl methacrylate, -Diphenyl-4-methyl-1-pentene in an amount of 10.1 mol% based on the total amount. The ratio of the pendant acrylate was 20.4 mol%.

Copolymer B was soluble in toluene, xylene, THF, dichloroethane, dichloromethane and chloroform, and no gel formation was observed. The cast film of Copolymer B was also a clear film without turbidity.

(Synthesis Example 3)

, 5 mol of 1,4-butanediol diacrylate (990 g), 1 mol of dicyclopentyl methacrylate (144.2 g), 4 mol of 2-hydroxypropyl methacrylate (576.8 g) -Methyl-1-pentene and 2400 ml of toluene were put into a 10.0 L reactor, 240 mmol of benzoyl peroxide was added at 90 占 폚, and reacted for 6 hours. After the polymerization reaction was stopped by cooling, the reaction mixture was poured into a large amount of hexane at room temperature to precipitate a polymer. The obtained polymer was washed with hexane, filtered, dried and weighed to obtain a copolymer C.

The copolymer C had Mw of 9230, Mn of 3210, and Mw / Mn of 2.88. By conducting ¹³ C-NMR, ¹ H-NMR analysis and elemental analysis, copolymer C contained 45.6 mol% of the structural units derived from 1,4-butanediol diacrylate in total, and the structural units derived from dicyclopentanyl methacrylate as the total 12.3 mol%, and 42.1 mol% of a structural unit derived from 2-hydroxypropyl methacrylate. Also, the terminal group of the structure derived from 2,4-diphenyl-4-methyl-1-pentene is preferably 1,4-butanediol diacrylate, dicyclopentanyl methacrylate, 2-hydroxypropyl methacrylate, -Diphenyl-4-methyl-1-pentene in an amount of 14.6 mol% based on the total amount. The ratio of the pendant acrylate was 32.6 mol%.

Copolymer C was soluble in toluene, xylene, THF, dichloroethane, dichloromethane and chloroform, and no gel formation was observed. Also, the cast film of the copolymer C was a transparent film having no turbidity.

(Synthesis Examples 4 to 15 and Synthesis Examples 16 to 20)

Using the same method as in Synthesis Example 1, various copolymers were synthesized by changing the kind and amount of acrylates to the blend shown in Tables 1 and 2. [ Synthesis Examples 1 to 15 are examples, and Synthesis Examples 16 to 20 are synthesis examples for comparison. The results are summarized in Tables 5 to 8.

(Examples 14 to 38 and Comparative Examples 7 to 14)

Various copolymers synthesized in Synthesis Example and additives such as (meth) acrylates, silica fine particles and polymerization initiator were mixed in the ratios shown in Tables 9 to 11 to obtain a curable composition. Next, the curable resin composition was cured by the various test methods described above and evaluated for performance. The performance evaluation results are shown in Tables 9 to 11.

In Tables 5 to 8, the numerals of the components (a) to (c) represent amounts used (moles), the numbers in parentheses are mole% in acrylates, the numbers of DMPs are amounts used (moles) Is the mol% based on the total amount of acrylates. When MMA is used as the other monomer component, it is calculated as acrylates. The content of each component is the abundance ratio (molar ratio) of the structural units derived from each component present in the copolymer, and is calculated by the above formulas (1) to (5), respectively. When MMA is used as the other monomer component, it is calculated as a structural unit derived from acrylates.

Further, in Tables 9 to 11, the weight of the silica of the component (C) is the weight of the solid component excluding the solvent component. In the evaluation of the heat cycle resistance and moisture resistance,? Indicates no peeling and X indicates peeling.

Claims (12)

(Meth) acrylic acid ester (a) having an alicyclic structure, a monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group, a bifunctional (meth) acrylic acid ester (c) (Meth) acrylate ester (c) derived from a bifunctional (meth) acrylic acid ester (c) in the side chain, wherein the (meth) And a structural unit derived from 2,4-diphenyl-4-methyl-1-pentene (d) at the terminal,
(B), a bifunctional (meth) acrylic acid ester (c) and a 2,4-diphenyl (meth) acrylate ester having an alicyclic structure, (A) is 10 (a) based on 100 moles of the total structural units, and (b), (c) and (B) is 10 to 45 moles, (c) is 10 to 50 moles, (d) is 5 to 20 moles,
The amount of the reactive (meth) acrylate group (c1) derived from the bifunctional (meth) acrylate ester (c) is 0.05 to 0.5 as the molar fraction (M _c1 ) represented by the following formula (2)
M _c1 = (c1) / [(a) + (b) + c]
(A), (b) and (c) are derived from a monofunctional (meth) acrylic acid ester (a) having an alicyclic structure and a structural unit derived from a monofunctional (C1) represents the number of moles of a structural unit containing a reactive (meth) acrylate group (c1), and (c1) represents the number of moles of a structural unit containing a reactive (meth) acrylate group
Soluble polyfunctional (meth) acrylic acid ester copolymer having a weight average molecular weight of 2,000 to 20,000, and being soluble in toluene, xylene, tetrahydrofuran, dichloroethane or chloroform. delete delete The method according to claim 1,
Wherein the monofunctional (meth) acrylic acid ester (a) having an alicyclic structure is selected from the group consisting of isobonyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, dicyclopentenyl acrylate, At least one monofunctional (meth) acrylate selected from the group consisting of dicyclopentanyl methacrylate, dicyclopentenyl acrylate, dicyclopentanyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentenyloxyethyl methacrylate and dicyclopentanyl methacrylate (Meth) acrylic acid ester copolymer. The method according to claim 1,
Wherein the monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group is selected from the group consisting of 2-hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate and partially ethoxylated 2-hydroxy methacrylate (Meth) acrylic acid ester having at least one alcoholic hydroxyl group selected from the group consisting of (meth) acrylic acid esters. The method according to claim 1,
Wherein the bifunctional (meth) acrylic acid ester (c) is at least one bifunctional (meth) acrylic acid ester selected from the group consisting of cyclohexanedimethanol diacrylate and dimethyloltricyclodecane diacrylate Soluble polyfunctional (meth) acrylic acid ester copolymer. A process for producing the soluble polyfunctional (meth) acrylic acid ester copolymer according to claim 1,
(D) is present in an amount of 10 to 500 parts by weight based on 100 parts by weight of the bifunctional (meth) acrylic acid ester (c)
(Meth) acrylic acid ester (a) having an alicyclic structure, the monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group and the bifunctional (meth) acrylic acid ester (c) , 10 to 40 mol% of a monofunctional (meth) acrylic acid ester (a) having an alicyclic structure, 10 to 40 mol% of a monofunctional (meth) acrylic acid ester (b) having an alcoholic hydroxyl group, Wherein the monomer component comprising 20 to 50 mol% of the ester (c) is polymerized at a temperature of 50 to 200 캜. (A): The soluble polyfunctional (meth) acrylic acid ester copolymer according to claim 1,
(B): a monomer having at least one functional group having an unsaturated double bond and having a molecular weight of 1000 or less, and
(C): fine particles of silica having an average particle size of 1 to 100 nm
And a curing agent. 9. The method of claim 8,
(B) is contained in an amount of 83 to 2 wt%, and the amount of the component (C) is 15 to 90 wt% based on the total of the components (A) and (B) Wherein the curable resin composition is a curable resin composition. 9. The method of claim 8,
Wherein the component B is at least one (meth) acrylate ester selected from a monofunctional (meth) acrylate ester having an alicyclic structure and a bifunctional (meth) acrylic acid ester. 9. The method of claim 8,
And a photopolymerization initiator as a component (D). A cured product obtained by curing the curable resin composition according to any one of claims 8 to 11.