WO2010004959A1

WO2010004959A1 - Energy ray-curable resin composition for optical lens sheet and cured product thereof

Info

Publication number: WO2010004959A1
Application number: PCT/JP2009/062293
Authority: WO
Inventors: 典子清柳; 淳子市川; 和義山本; 律子設楽; 貴文水口
Original assignee: 日本化薬株式会社
Priority date: 2008-07-11
Filing date: 2009-07-06
Publication date: 2010-01-14
Also published as: TW201012833A; JPWO2010004959A1

Abstract

Disclosed is a flame-retardant resin composition having high refractive index, high glass transition temperature and low viscosity, while exhibiting excellent mold releasability, excellent shape reproducibility and excellent adhesion to a base. Specifically disclosed is an energy ray-curable resin composition for optical lens sheet, said composition containing a monoacrylate monomer (A) having a phenyl ether group, a compound (B) represented by general formula (1) (wherein R represents a hydrogen atom or a methyl group) and a photopolymerization initiator (C).

Description

Energy ray curable resin composition for optical lens sheet and cured product thereof

The present invention relates to an energy ray curable resin composition for an optical lens sheet and a cured product thereof. More specifically, the present invention relates to a resin composition and a cured product particularly suitable for lenses such as a Fresnel lens, a lenticular lens, a prism lens, and a microlens.

Conventionally, the above-described lens has been molded by a method such as a press method or a cast method (casting method). The former pressing method was poor in productivity because it was manufactured by heating, pressurizing and cooling cycles. Further, the latter casting method has a problem that it takes a long manufacturing time because a monomer is poured into a mold for polymerization, and a manufacturing cost increases because a large number of molds are required. In order to solve such a problem, various proposals have been made for using an ultraviolet curable resin composition (Patent Documents 1 and 2).

A method for producing an optical lens sheet used for a transmission screen or the like by using these ultraviolet curable resin compositions has been somewhat successful. However, the cured products of these conventional resin compositions have a problem of poor adhesion to the substrate and releasability from the mold. If the adhesion is poor, the types of substrates that can be used are limited, making it difficult to obtain the intended optical properties. If the releasability is poor, the resin remains in the mold at the time of mold release, and the mold cannot be used. In addition, a resin composition that gives a cured product with good adhesion is likely to have poor mold releasability because of good adhesion to the mold. On the other hand, a resin composition with good mold releasability tends to have poor adhesion. is there. Therefore, it is desired to provide a resin composition that can satisfy both the performance of adhesion to the substrate and the releasability from the mold.

With regard to the composition for lenses used in these optical lens sheets and the like, a resin composition having a high refractive index is desired along with recent high-definition images and thinner final products. In order to be processed into a shape, processed thinner, or continuously processed into a roll-like sheet or film, a low-viscosity one tends to be required. Furthermore, it is necessary that the microstructure is not easily crushed when the lens sheet is wound up, and in this case, a high glass transition temperature (Tg) is required.

Among them, Patent Document 3 proposes a resin composition having both adhesiveness and releasability, but it cannot be said that the viscosity for processing into a finer shape is sufficient. Document 4 proposes a resin composition with a high refractive index, but does not mention adhesion and releasability, and has a fine structure with a high refractive index that balances adhesion and releasability. A proposal for a request for an optical lens sheet having the above is not described in any patent document. Patent Document 5 describes a thermosetting flame-retardant acrylic resin composition mainly composed of a DOPO derivative (Patent Document 5: general formula (1)) and a flexible acrylic resin, which is used as an adhesive. Yes. However, it does not describe an energy ray curable resin composition for lens sheets containing a monoacrylate monomer having a phenyl ether group.

In addition, there is a tendency to obtain a cured product having as high a glass transition temperature (Tg) as possible so that the change in physical properties is small even when the optical lens sheet is used in a high temperature environment. In order to prevent physical properties from being deteriorated due to coloring, those having good light resistance are required, and recently, it is sometimes required to use flame-retardant materials for parts such as home appliances. However, it is difficult to combine high refractive index, high Tg point, releasability, adhesion, low viscosity, light resistance, and incombustibility, and none satisfying all of them has been obtained.

JP 63-167301 A JP-A 63-199302 Japanese Patent No. 3209554 Japanese Patent No. 3454544 JP 2007-231091 A

The object of the present invention is to provide a low-viscosity resin composition suitable for the production of lens sheets such as Fresnel lenses, lenticular lenses, prism lenses, and micro lenses, as well as excellent releasability, mold reproducibility, adhesion, and high refractive index. The present invention provides a cured product that is flame retardant.

As a result of intensive studies to solve the above problems, the present inventors have found that an ultraviolet curable resin composition having a specific composition and a cured product thereof can solve the above problems, and have completed the present invention.

That is, the present invention relates to (1) a monoacrylate monomer (A) having a phenyl ether group, the general formula (1)
A compound represented by formula (B)

(In the formula, R represents a hydrogen atom or a methyl group.)
And an energy ray curable resin composition for an optical lens sheet comprising a photopolymerization initiator (C),
(2) Monoacrylate monomer (A) having a phenyl ether group is o-phenylphenol (poly) ethoxy (meth) acrylate, p-phenylphenol (poly) ethoxy (meth) acrylate, o-phenylphenol epoxy (meth) acrylate , The resin composition according to the above (1), which is p-phenylphenol epoxy (meth) acrylate,
(3) The above (1) and (2) further comprising a (meth) acrylate compound (D) other than the monoacrylate monomer (A) having a phenyl ether group and the compound (B) represented by the general formula (1) The resin composition according to
(4) The resin composition according to (3), wherein the (meth) acrylate compound (D) is a compound having a structure containing a bisphenol A skeleton,
(5) The resin composition according to any one of (1) to (4), wherein the viscosity at 25 ° C. measured with an E-type viscometer is 3000 mPa · s or less.
(6) A cured product having a refractive index at 25 ° C. of 1.55 or more obtained by curing the resin composition according to any one of (1) to (5),
(7) An optical lens sheet using the cured product according to (6),
About.

The resin composition of the present invention has a low viscosity, and its cured product is excellent in releasability, mold reproducibility, adhesion to a substrate, and has a high refractive index. Therefore, it is particularly suitable for optical lens sheets such as Fresnel lenses, lenticular lenses, prism lenses, and micro lenses.

The resin composition of the present invention contains a monoacrylate monomer (A) having a phenyl ether group, a compound (B) represented by the general formula (1), and a photopolymerization initiator (C).

The monoacrylate monomer (A) having a phenyl ether group that can be used in the present invention will be described.

Examples of the monoacrylate monomer (A) having a phenyl ether group include phenoxyethyl (meth) acrylate, phenyl polyethoxy (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, tribromophenyloxyethyl (meth) acrylate, Examples thereof include phenylthioethyl (meth) acrylate, phenylphenol polyethoxy (meth) acrylate, phenylphenol epoxy (meth) acrylate, etc. Among them, o-phenylphenol (poly) ethoxy (meth) acrylate, p-phenylphenol (Poly) ethoxy (meth) acrylate, o-phenylphenol epoxy (meth) acrylate, and p-phenylphenol epoxy (meth) acrylate are preferred. In the present invention, the monoacrylate monomer (A) may be used alone or in combination of two or more.

As the phenylphenol polyethoxy (meth) acrylate, a compound having an average number of repeating ethoxy structure moieties of 1 to 3 is preferable, and reaction of o-phenylphenol, p-phenylphenol, which is a raw material, with ethylene oxide It can be obtained by reacting the product with (meth) acrylic acid. o-Phenylphenol and p-phenylphenol are commercially available products, for example, O-PP and P-PP, both available from Sanko Co., Ltd. The reaction product of phenylphenol and ethylene oxide can be obtained by a known method, and a commercially available product can also be used. In the presence of an esterification catalyst such as p-toluenesulfonic acid or sulfuric acid and a polymerization inhibitor such as hydroquinone or phenothiazine, the reaction product of phenylphenol and ethylene oxide is preferably a solvent (for example, toluene, cyclohexane, n Phenylphenol polyethoxy (meth) acrylate is obtained by reacting with (meth) acrylic acid, preferably at 70 to 150 ° C. in the presence of (hexane, n-heptane, etc.). The proportion of (meth) acrylic acid used is 1 to 5 mol, preferably 1.05 to 2 mol, per mol of the reaction product of phenylphenol and ethylene oxide. The amount of the esterification catalyst is 0.1 to 15 mol%, preferably 1 to 6 mol%, based on (meth) acrylic acid used.

As phenylphenol epoxy (meth) acrylate, the above-mentioned o-phenylphenol and p-phenylphenol are reacted with epihalohydrin in the presence of an alkali metal hydroxide, and the resulting epoxy resin is reacted with acrylic acid. Can be obtained.

As the epihalohydrin, epichlorohydrin, α-methylepichlorohydrin, γ-methylepichlorohydrin, epibromohydrin and the like can be used, and among them, epichlorohydrin which is easily available industrially is preferable.
The amount of epihalohydrin used is usually 2 to 20 mol, preferably 3 to 15 mol, per 1 mol of phenylphenol.

Examples of the alkali metal hydroxide include sodium hydroxide and potassium hydroxide, and a solid substance or an aqueous solution thereof may be used. When using an aqueous solution, the aqueous solution of the alkali metal hydroxide is continuously added to the reaction system, and water and epihalohydrin are distilled off continuously under reduced pressure or normal pressure, followed by liquid separation to remove the water. Alternatively, the epihalohydrin may be continuously returned to the reaction system. The amount of alkali metal hydroxide used is usually 0.1-10.0 mol, preferably 0.3-5.0 mol, more preferably 1 mol per 1 mol of o-phenylphenol and p-phenylphenol. 0.8 to 3.0 moles.

In order to accelerate the reaction, it is preferable to add a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, trimethylbenzylammonium chloride as a catalyst. When a quaternary ammonium salt is used, the amount used is usually 0.1 to 20 g, preferably 0.2 to 15 g, with respect to 1 mol of the o-phenylphenol and p-phenylphenol.

In this case, it is preferable for the reaction to proceed by adding an aprotic polar solvent such as aliphatic alcohols such as methanol, ethanol and isopropyl alcohol, dimethylsulfone, dimethylsulfoxide, tetrahydrofuran and dioxane.

When alcohols are used, the amount used is usually 1 to 50% by mass, preferably 2 to 30% by mass, based on the amount of epihalohydrin used. When an aprotic polar solvent is used, it is usually 3 to 100% by mass, preferably 5 to 80% by mass, based on the amount of epihalohydrin used.

The reaction temperature is usually 30 to 100 ° C, preferably 35 to 90 ° C. The reaction time is usually 0.2 to 10 hours, preferably 0.5 to 8 hours. In the presence of an alkali metal hydroxide, epihalohydrin and the like are removed under heating and reduced pressure after washing the reaction solution of phenylphenol and epihalohydrin with or without washing with water. Furthermore, in order to obtain an epoxy resin with less hydrolyzable halogen, the obtained epoxy resin is dissolved in a solvent such as toluene or methyl isobutyl ketone, and an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is dissolved. The reaction can be carried out by adding an aqueous solution to ensure ring closure. In this case, the amount of alkali metal hydroxide used is usually 0.01 to 0.5 mol, preferably 0.05 to 0.3 mol, relative to 1 mol of phenylphenol used. The reaction temperature is usually 50 to 120 ° C., and the reaction time is usually 0.5 to 2 hours.

After completion of the reaction, the produced salt is removed by filtration, washing with water, etc., and the solvent is distilled off under heating and reduced pressure to obtain the desired epoxy resin. An epoxy resin that can be used without special purification is obtained by a method represented by such a formulation.

Phenylphenol epoxy (meth) acrylate is obtained by reacting the aforementioned epoxy resin with (meth) acrylic acid. (Meth) acrylic acid is preferably reacted in an amount of 0.8 to 1.1 equivalents, more preferably 0.9 to 1.05 equivalents, based on an epoxy equivalent of 1 of the epoxy resin.

The reaction can be carried out without a solvent, but if necessary, a solvent having no alcoholic hydroxyl group, for example, ketones such as acetone, ethylmethylketone and cyclohexanone, and aromatics such as benzene, toluene, xylene and tetramethylbenzene Aromatic hydrocarbons, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether and other glycol ethers, ethyl acetate, butyl acetate, methyl cellosolve acetate , Ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether monoacetate, Esters such as dialkyl talates, dialkyl succinates and dialkyl adipates, cyclic esters such as γ-butyrolactone, petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha and solvent naphtha, and monoacrylates described later Among various monomers such as monomer (C) and (meth) acrylate compound (D), those having no alcoholic hydroxyl group, such as acryloylmorpholine, terminal acrylate ester of 2-phenylphenol ethylene oxide adduct (for example, , Nippon Kayaku Co., Ltd. OPP-1, OPP-2), polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane polyethoxytri ( Meta ) Acrylate, glycerin polypropoxytri (meth) acrylate, di (meth) acrylate of ε-caprolactone adduct of hydroxypivalate neopentyl glycol (for example, KAYARAD HX-220, HX-620 manufactured by Nippon Kayaku Co., Ltd.) ), Pentaerythritol tetra (meth) acrylate, poly (meth) acrylate which is a reaction product of dipentaerythritol and ε-caprolactone, dipentaerythritol poly (meth) acrylate, or the like alone or in a mixed organic solvent.

During the reaction, it is preferable to use a catalyst for promoting the reaction. When the catalyst is used, the amount of the catalyst used is 0.1 to 10% by mass with respect to the reaction product. The reaction temperature at that time is 60 to 150 ° C., and the reaction time is preferably 5 to 60 hours. Examples of the catalyst used include triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, triphenylstibine, methyltriphenylstibine, chromium octoate, zirconium octoate and the like. Can be mentioned.

Further, a thermal polymerization inhibitor may be used, and examples of the thermal polymerization inhibitor include hydroquinone monomethyl ether, 2-methylhydroquinone, hydroquinone, 2,6-di-tert-butyl-p-cresol, and diphenylpicryl. Examples include hydrazine and diphenylamine. When a thermal polymerization inhibitor is used, it is preferably used in an amount of about 0.1 to 10% by mass with respect to the reaction product. The reaction is terminated at an appropriate time when the acid value of the sample is 5 mg · KOH / g or less, preferably 3 mg · KOH / g or less.

The compound (B) represented by the general formula (1) used in the resin composition of the present invention will be described below.

Compound (B) is obtained by reacting an alcohol compound of formula (2) with a monocarboxylic acid compound having an ethylenically unsaturated group in the molecule.

The alcohol compound represented by the above formula (2) is obtained by reacting a phosphorus-containing compound having at least one active hydrogen in the molecule as shown in the following formula (3) with formaldehyde. This compound can use a commercial item, for example, the brand name HCA by Sanko Co., Ltd. is mentioned.

The monocarboxylic acid compound having an ethylenically unsaturated group in the molecule for producing the compound (B) is reacted in order to give the compound (B) reactivity to active energy rays. Specific examples include acrylic acid and (meth) acrylic acid.

Compound (B) is a dehydration-condensation of an alcohol compound of formula (2) and a monocarboxylic acid compound having an ethylenically unsaturated group in the molecule (hereinafter referred to as “(meth) acrylic acid”) in the presence of an acid catalyst. It can be manufactured by a method.

The acid catalyst used can be arbitrarily selected from known ones such as sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, and the amount used is usually 0.1 to 10 mol% with respect to (meth) acrylic acid or the like. Preferably, it is 1 to 5 mol%.

An azeotropic solvent can be used to distill off the water produced by the reaction. The azeotropic solvent here has a boiling point of 60 to 130 ° C. and can be easily separated from water, and in particular, an aliphatic hydrocarbon such as n-hexane and n-heptane, and an aromatic such as benzene and toluene. The use of alicyclic hydrocarbons such as aromatic hydrocarbons and cyclohexane is preferred. The amount used is arbitrary, but is preferably 10 to 70% by mass with respect to the reaction mixture.
The reaction temperature may be in the range of 60 to 130 ° C, but 75 to 120 ° C is preferable from the viewpoint of shortening the reaction time and preventing polymerization.

Usually, a commercially available (meth) acrylic acid or the like used as a raw material has already been added with a polymerization inhibitor such as p-methoxyphenol, but a polymerization inhibitor may be added again during the reaction. Examples of such polymerization inhibitors include hydroquinone, p-methoxyphenol, 2,4-dimethyl-6-t-butylphenol, 3-hydroxythiophenol, p-benzoquinone, 2,5-dihydroxy-p-benzoquinone, Phenothiazine and the like are preferable. The amount used is 0.01 to 1% by mass with respect to the reaction raw material mixture.

Furthermore, in addition to the monoacrylate monomer (A) having the phenyl ether group mentioned above, the compound (B) represented by the general formula (1), the viscosity and adhesion of the obtained resin composition of the present invention, Considering the glass transition temperature (Tg), the hardness of the cured product, etc., the (meth) acrylate compound (D) other than the component (A) and the component (B) may be used alone or in combination of two or more. Good. Examples of the (meth) acrylate compound (D) include (meth) acrylate monomers and (meth) acrylate oligomers.

Examples of the (meth) acrylate monomer include a monofunctional (meth) acrylate monomer, a bifunctional (meth) acrylate monomer, a trifunctional or higher polyfunctional (meth) acrylate monomer, and the like.

Examples of the monofunctional (meth) acrylate monomer include acryloylmorpholine, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, cyclohexane-1,4-dimethanol mono (meth) acrylate, and tetrahydrofurfuryl. (Meth) acrylate, phenoxyethyl (meth) acrylate, phenyl polyethoxy (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, isobornyl (meth) acrylate , Tribromophenyloxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) Or the like can be mentioned acrylate.

Examples of bifunctional (meth) acrylate monomers include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, and tricyclodecanedi. Methanol (meth) acrylate, bisphenol A polyethoxydi (meth) acrylate, bisphenol A polypropoxydi (meth) acrylate, bisphenol F polyethoxydi (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate hydroxypivalic acid Examples include di (meth) acrylates of ε-caprolactone adducts of neopentyl glycol (for example, KAYARAD HX-220, HX-620, etc., manufactured by Nippon Kayaku Co., Ltd.). .

Examples of the trifunctional or higher polyfunctional (meth) acrylate monomer include tris (acryloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, Examples include pentaerythritol hexa (meth) acrylate, tripentaerythritol penta (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane polyethoxytri (meth) acrylate, and ditrimethylolpropane tetra (meth) acrylate. it can.

Examples of (meth) acrylate oligomers include urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate.

Examples of the urethane (meth) acrylate include diol compounds (for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, neopentyl glycol, 1,6- Hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentane Diol, 2-butyl-2-ethyl-1,3-propanediol, cyclohexane-1,4-dimethanol, polyethylene glycol, polypropylene glycol, bisphenol A polyethoxydiol, bisphenol A polypropoxydiol Etc.) or a reaction product of these diol compounds with dibasic acids or anhydrides thereof (for example, succinic acid, adipic acid, azelaic acid, dimer acid, isophthalic acid, terephthalic acid, phthalic acid or their anhydrides) Polyester diol and organic polyisocyanate (for example, chain saturated hydrocarbon isocyanate such as tetramethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate) , Norbornane diisocyanate, dicyclohexylmethane diisocyanate, methylenebis (4-cyclohexylisocyanate), hydrogenated diphenylmethane diisocyanate, hydrogenated xylene diisocyanate Cyclic saturated hydrocarbon isocyanates such as hydrogenated toluene diisocyanate, 2,4-tolylene diisocyanate, 1,3-xylylene diisocyanate, p-phenylene diisocyanate, 3,3′-dimethyl-4,4′-diisocyanate, An aromatic polyisocyanate such as 6-isopropyl-1,3-phenyl diisocyanate and 1,5-naphthalene diisocyanate) and then a hydroxyl group-containing (meth) acrylate is added. Moreover, the compound etc. which made the said organic polyisocyanate and the hydroxyl-containing (meth) acrylate react are mentioned.

Epoxy (meth) acrylates include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, terminal glycidyl ether of bisphenol A propylene oxide adduct, and fluorene epoxy resin and (meth) A reaction product with acrylic acid can be mentioned.

Examples of the polyester (meth) acrylate include a reaction product of polyester diol which is a reaction product of the above diol compound and the above dibasic acid or anhydride thereof, and (meth) acrylic acid.

Among them, the (meth) acrylate compound (D) that can be used for the resin composition of the present invention is preferably a compound having a structure containing a bisphenol A skeleton in consideration of the refractive index. For example, bisphenol A polyethoxydi (meth) acrylate, bisphenol (Meth) acrylate monomers such as A polypropoxy di (meth) acrylate, urethane (meth) acrylate oligomers having a bisphenol A skeleton (diol compounds such as bisphenol A polyethoxydiol and bisphenol A polypropoxydiol, or these diol compounds and A compound obtained by reacting a polyester diol, which is a reaction product of a dibasic acid or its anhydride, an organic polyisocyanate, and a hydroxyl group-containing (meth) acrylate), bisphenol A bone Epoxy (meth) acrylate oligomer (bisphenol A type epoxy resins, reaction products of epoxy resins such as terminal glycidyl ethers of a propylene oxide adduct of bisphenol A and (meth) acrylic acid, etc.) are suitable with.

As the methacrylate compound (D), in order to improve the refractive index, (meth) acrylate having a fluorene skeleton, di (meth) acrylate having a binaphthol skeleton, acrylate having a carbazolyl group, phenylphenol epoxy acrylate and aromatic organic Urethane acrylate or the like reacted with polyisocyanate can be used.

In consideration of the adhesiveness and viscosity of the cured product, a monofunctional or bifunctional (meth) acrylate monomer is suitable as the (meth) acrylate compound (D), and among them, acryloylmorpholine, tetrahydrofurfuryl (meth). Acrylate, phenoxyethyl (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclo Pentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and the like are preferable.

In consideration of the glass transition temperature (Tg) of the cured product, the (meth) acrylate compound (D) includes tris (acryloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Trifunctional or higher functional (meth) acrylate monomers such as dipentaerythritol penta (meth) acrylate and trimethylolpropane tri (meth) acrylate are preferred.

Examples of the photopolymerization initiator (C) contained in the resin composition of the present invention include benzoins 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-2-methyl-phenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2 -Acetophenones such as methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone] 2-ethyla Anthraquinones such as nthraquinone, 2-tert-butylanthraquinone, 2-chloroanthraquinone, 2-amylanthraquinone; thioxanthones such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone; acetophenone dimethyl ketal, benzyldimethyl Ketals such as ketals; benzophenones such as benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 4,4'-bismethylaminobenzophenone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4 , 6-trimethylbenzoyl) -phenylphosphine oxide, phosphine oxides such as diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide, etc. It can be mentioned. Preferred are acetophenones, and more preferred are 2-hydroxy-2-methyl-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone. In the resin composition of the present invention, the photopolymerization initiator (C) may be used singly or as a mixture of a plurality of types, but 2,4,6-trimethylbenzoyldiphenylphosphine oxide It is preferable to use at least one phosphine oxide such as bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide.

The use ratio of each component of the resin composition of the present invention is determined in consideration of the desired refractive index, glass transition temperature, viscosity, adhesion, etc., but component (A) + component (B) + component (D) The content of component (A) + component (B) is 50 to 100 parts by mass, particularly preferably 70 to 100 parts by mass, and therefore the content of component (D) is The amount is less than 50 parts by mass, particularly preferably less than 30 parts. When the total amount of component (A) + component (B) is 100 parts by mass, the content of component (A) is 10 to 95 parts by mass, particularly preferably 20 to 90 parts by mass. . Component (C) is usually used in an amount of 0.1 to 10 parts by weight, particularly preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the total amount of component (A) + component (B) + component (D). Part.

In addition to the above components, the energy ray curable resin composition of the present invention includes a mold release agent, an antifoaming agent, a leveling agent, a light stabilizer, an antioxidant, and a polymerization prohibition in order to improve convenience during handling. An agent, an antistatic agent, an ultraviolet absorber and the like can be used in combination depending on the situation. Furthermore, polymers such as acrylic polymer, polyester elastomer, urethane polymer and nitrile rubber, inorganic or organic light diffusing filler, and the like can be added as necessary. Although the resin composition of the present invention can be obtained by adding a solvent as necessary, in the present invention, it is preferable not to add a solvent.

The resin composition of the present invention can be prepared by mixing and dissolving each component according to a conventional method. For example, each component can be charged into a round bottom flask equipped with a stirrer and a thermometer and stirred at 40 to 80 ° C. for 0.5 to 6 hours.

The viscosity of the resin composition of the present invention is 3,000 mPa · s at 25 ° C. measured using an E-type viscometer (TV-200: manufactured by Toki Sangyo Co., Ltd.) as a viscosity suitable for producing optical lens sheets. Compositions that are s or less are preferred.

A cured product obtained by curing the resin composition of the present invention by irradiating energy rays such as ultraviolet rays according to a conventional method is also included in the present invention. The cured product is obtained by applying the resin composition of the present invention on a stamper having a shape of, for example, a Fresnel lens, a lenticular lens, or a prism lens to form a layer of the resin composition, and a hard transparent substrate on the layer. A back sheet (for example, a substrate or film made of polymethacrylic resin, polycarbonate resin, polystyrene resin, polyester resin, or a blend of these polymers) is adhered, and then ultraviolet light is emitted from the hard transparent substrate side by a high-pressure mercury lamp or the like. After the resin composition is cured by irradiation, the cured product can be peeled off from the stamper. Moreover, it can also carry out by a continuous process as these applications.

In this manner, an optical lens having a high refractive index (25 ° C.) and an optical lens portion such as a Fresnel lens, a lenticular lens, a prism lens, and a microlens having a high releasability, mold reproducibility, adhesion, and light resistance. Sheets can be obtained and these are also included in the present invention. The refractive index can be measured with an Abbe refractometer (DR-M2: manufactured by Atago Co., Ltd.).

The resin composition of the present invention is useful as an optical lens sheet as described above. Applications other than those for optical lens sheets include various coating agents and adhesives.

Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited at all by the following examples.

Synthesis Example 1 Synthesis of Compound (A)
A flask equipped with a thermometer, a condenser, and a stirrer was charged with 181 g of p-phenylphenol (P-PP Sanko Co., Ltd.), 394 g of epichlorohydrin, and 80 g of methanol while being purged with nitrogen gas. The mixture was further heated to 70 ° C., 44 g of flaky sodium hydroxide was added in portions over 90 minutes, and then reacted at 70 ° C. for 60 minutes. After the completion of the reaction, washing was performed twice with 200 g of water to remove the generated salt and the like, and then an excess amount was added in 3 hours with stirring under heating and reduced pressure (˜70 ° C., −0.08 MPa to −0.09 MPa). Epichlorohydrin and the like were distilled off. To the residue, 480 g of methyl isobutyl ketone was added and dissolved, and the temperature was raised to 70 ° C. Under stirring, 12 g of a 10% by mass aqueous sodium hydroxide solution was added and reacted for 1 hour, followed by washing with water until the washing water became neutral, and the resulting solution was subjected to methyl isobutyl ketone under reduced pressure using a rotary evaporator. 227 g of the desired epoxy resin (a-1) was obtained by distilling off the etc. The obtained epoxy resin (a-1) had an epoxy equivalent of 242 g / eq. It was white crystalline at room temperature.
Next, in a 1 L flask equipped with a stirrer and a reflux tube, 145.2 g (0.6 eq.) Of the epoxy resin (a-1) obtained above was used as a thermal polymerization inhibitor. -0.57 g of tert-butyl-p-cresol, 43.3 g (0.6 eq.) Of acrylic acid, and 0.57 g of triphenylphosphine as a reaction catalyst were allowed to react at 98 ° C for 30 hours, and the acid value was measured. As a result, it was 1.2 mg · KOH / g, and a product which was white crystals at room temperature was obtained. The refractive index was 1.588.

Synthesis Example 2 Synthesis of Compound (B) 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (HCA manufactured by Sanko Co., Ltd.) was added to a 2 L reactor equipped with a stirrer, a thermometer, and a condenser. Was charged with 216.2 g (1.0 mol) and 246.2 g of toluene, and dissolved at a temperature of 80 to 90 ° C. Next, with stirring, 30.0 g (1.0 mol) of paraformaldehyde was gradually added and reacted at a reaction temperature of 80 ° C. to 90 ° C. for 3 hours to obtain 246.2 g of white crystals.
Next, 246.2 g (1.0 mol) of the obtained crystal product, 144.7 g (2.0 mol) of acrylic acid, 400 g of toluene, 1.5 g of methoquinone, and 14.5 g of P-toluenesulfonic acid monohydrate were charged. The dehydration condensation reaction was carried out at 105-110 ° C. for 13 hours, and the resulting reaction solution was washed twice with 10% by mass aqueous sodium carbonate solution and once with 20% by mass saline solution, and then toluene was distilled under reduced pressure to obtain a pale yellow liquid. 267.9 g (yield 89.2%) of the phosphine oxide compound (B) was obtained.
This compound (B) exhibits the following physical properties.
Viscosity (40 ℃) 6300 CPS
Refractive index (20 ° C) 1.613
¹ H-NMR
4.80ppm = 2H, 5.60ppm = 1H, 6.16ppm = 1H, 6.45ppm = 1H, 7.24-7.93ppm = 8H

Synthesis of compound (D)
Synthesis example 3
In a dry container, 94.7 parts of o-phenylphenol monoethoxyacrylate and 139.3 parts of 2,4-tolylene diisocyanate were charged, and bisphenol A poly (n = 2) propoxydiol (hydroxyl value 312 mgKOH / g) 143. Nine parts were charged in three portions while confirming heat generation, stirred at 80 ° C., and reacted for about 10 hours. When the isocyanate group content in the reaction system reached 11.9% by mass, 95.7 parts of 2-hydroxyethyl acrylate, 0.2 part of p-methoxyphenol and 0.06 part of di-n-butyltin dilaurate were charged. The reaction was carried out at 80 ° C. for about 12 hours, and the reaction was terminated when the isocyanate group content was 0.1% by mass or less.

The resin composition and the cured product of the present invention were obtained with the composition as shown in the following examples (numerical values indicate parts by mass). The evaluation method and evaluation criteria for the resin composition and the cured film were as follows.

(1) Viscosity: Viscosity was measured at 25 ° C. using an E-type viscometer (TV-200: manufactured by Toki Sangyo Co., Ltd.).
(2) Releasability: Expresses the degree of difficulty when releasing a cured resin from a mold.
○ ···························································································································· ) Mold reproducibility: The surface shape of the cured UV curable resin layer and the surface shape of the mold were observed.
○ ···· Reproducibility is good × ··· Reproducibility is poor

(4) Adhesion: A test piece was prepared by applying a resin composition on a substrate to a film thickness of about 50 μm and then irradiating it with a high-pressure mercury lamp (80 W / cm, ozone-less) at 1000 mJ / cm ^2. The adhesion was evaluated according to JIS K5600-5-6.
In the evaluation results, 0 to 2 were marked with ◯, and 3 to 5 were marked with ×.

(5) Refractive index (25 ° C.): The refractive index (25 ° C.) of the cured ultraviolet curable resin layer was measured with an Abbe refractometer (DR-M2: manufactured by Atago Co., Ltd.).
(6) Glass transition temperature (Tg): The Tg point of the cured ultraviolet curable resin layer was measured with a viscoelasticity measurement system (DMS-6000: manufactured by Seiko Denshi Kogyo Co., Ltd.) in a tensile mode at a frequency of 1 Hz.
(7) Flame retardancy: A cured film having a thickness of 200 μm was prepared using the resin composition, and was cut into strips having a width of 1 cm and a length of 10 cm to obtain test pieces. The test piece was fixed horizontally, and the flame of the lighter was kept close to the bottom for 10 seconds from one side, and then the state was observed by releasing the flame.
○ ··································································································································· The piece burns down

Example 1
As component (A), 62 parts of o-phenylphenol monoethoxyacrylate, as component (B), 15 parts of the compound obtained in Synthesis Example 2, as component (C), 5 parts of 1-hydroxy-cyclohexyl phenyl ketone, as component (D) 9 parts of KAYARAD R-551 (Nippon Kayaku: bisphenol A polyethoxydiacrylate) and 14 parts of KAYARAD R-115 (Nippon Kayaku: bisphenol A epoxy acrylate) were heated to 60 ° C. and mixed, A resin composition was obtained. The viscosity of this resin composition was 828 mPa · s. Moreover, the refractive index (25 degreeC) of the 200-micrometer-thick ultraviolet curable resin layer which hardened this resin composition by irradiating 600 mJ / cm < ² > with a high pressure mercury lamp (80 w / cm, ozone-less) is 1.602. The glass transition temperature (Tg) was 52 ° C.
Further, this resin composition was applied onto a prism lens mold so that the film thickness was 50 μm, and an easy-adhesion PET film (Toyobo Cosmo Shine A4300, 100 μm thickness) was adhered thereon as a base material. The prism lens sheet of the present invention was obtained from the top by being cured by irradiating with an ultraviolet ray of 1000 mJ / cm ^{2 with} a high-pressure mercury lamp and then curing.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 2
In Example 1, 42 parts of o-phenylphenol monoethoxyacrylate as component (A) and 20 parts of the compound (p-phenylphenol epoxy acrylate) obtained in Synthesis Example 1 were used, and diphenyl- (2, A resin composition of the present invention was obtained in the same manner as in Example 1 except that 0.1 part of 4,6-trimethylbenzoyl) phosphine oxide was added. The viscosity of this resin composition was 829 mPa · s. Moreover, the refractive index (25 degreeC) of the resin layer obtained by carrying out similarly to Example 1 was 1.603, and the glass transition temperature (Tg) was 51 degreeC.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 3
In Example 1, 52 parts of o-phenylphenol monoethoxyacrylate was used as component (A), 25 parts of the compound obtained in Synthesis Example 2 was used as component (B), and diphenyl- (2,4,6) was used as component (C). -Trimethylbenzoyl) Phosphine oxide 0.1 part was added and the present invention was used in the same manner as in Example 1 except that 23 parts of KAYARAD R-115 (Nippon Kayaku: bisphenol A epoxy acrylate) was used as component (D). A resin composition was obtained. The viscosity of this resin composition was 2511 mPa · s. The resin layer obtained in the same manner as in Example 1 had a refractive index (25 ° C.) of 1.606 and a glass transition temperature (Tg) of 59 ° C.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 4
In Example 1, 59 parts of o-phenylphenol monoethoxyacrylate was used as component (A), and 0.1 part of diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide was added as component (C). Example 1 except that 9 parts of KAYARAD R-551 (Nippon Kayaku: bisphenol A polyethoxydiacrylate), 14 parts of the product obtained in Synthesis Example 3, and 3 parts of acryloylmorpholine were used as component (D). The resin composition of the present invention was obtained. The viscosity of this resin composition was 1221 mPa · s. Moreover, the refractive index (25 degreeC) of the resin layer obtained by carrying out similarly to Example 1 was 1.602, and the glass transition temperature (Tg) was 50 degreeC.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 5
In Example 1, 0.1 part of diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide was added as the component (C), and KAYARAD R-551 (manufactured by Nippon Kayaku: Bisphenol A) was added as the component (D). Polyethoxydiacrylate) 4 parts, KAYARAD R-115 (Nippon Kayaku: bisphenol A epoxy acrylate) 14 parts, and 1,6-hexanediol diacrylate 5 parts were used in the same manner as in Example 1. A resin composition was obtained. The viscosity of this resin composition was 559 mPa · s. The resin layer obtained in the same manner as in Example 1 had a refractive index (25 ° C.) of 1.600 and a glass transition temperature (Tg) of 50 ° C.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 6
In Example 1, 0.1 part of diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide was added as the component (C), and KAYARAD R-551 (manufactured by Nippon Kayaku: Bisphenol A) was added as the component (D). Polyethoxydiacrylate) 4 parts, KAYARAD R-115 (Nippon Kayaku: bisphenol A epoxy acrylate) 14 parts, dipentaerythritol hexaacrylate 5 parts resin composition of the present invention as in Example 1 Got. The viscosity of this resin composition was 1025 mPa · s. The resin layer obtained in the same manner as in Example 1 had a refractive index (25 ° C.) of 1.601 and a glass transition temperature (Tg) of 53 ° C.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 7
In Example 1, 62 parts of o-phenylphenol monoethoxyacrylate was used as component (A), and 0.1 part of diphenyl- (2,4,6-trimethylbenzoyl) phosphine oxide was added as component (C). As component (D), 9 parts KAYARAD R-551 (Nippon Kayaku: bisphenol A polyethoxydiacrylate), 9 parts KAYARAD R-115 (Nippon Kayaku: bisphenol A epoxy acrylate), 5 parts dipentaerythritol hexaacrylate The resin composition of the present invention was obtained in the same manner as in Example 1 except that 5 parts of bisphenolfluorene ethoxydiacrylate was used. The viscosity of this resin composition was 812 mPa · s. The resin layer obtained in the same manner as in Example 1 had a refractive index (25 ° C.) of 1.605 and a glass transition temperature (Tg) of 50 ° C.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○.

Example 8
In Example 1, 27 parts of o-phenylphenol monoethoxyacrylate was used as component (A), 50 parts of the compound obtained in Synthesis Example 2 was used as component (B), and diphenyl- (2,4,6) was used as component (C). -Trimethylbenzoyl) 0.1 part of phosphine oxide was added, and 9 parts of KAYARAD R-551 (Nippon Kayaku: bisphenol A polyethoxydiacrylate) and 14 parts of dipentaerythritol hexaacrylate were used as component (D). Except for the above, a resin composition of the present invention was obtained in the same manner as in Example 1. The viscosity of this resin composition was 2672 mPa · s. Further, the refractive index (25 ° C.) of the resin layer obtained in the same manner as in Example 1 was 1.603.
Using the obtained resin composition, a prism lens sheet of the present invention was obtained in the same manner as in Example 1.
Evaluation results: releasability: ○, mold reproducibility: ○, adhesion: ○, flame retardancy: ○.

Comparative Example 1
According to Example 1 of Patent Document 1 (Japanese Patent Laid-Open No. 63-167301), 70 parts of Aronics M-315 (tris (2-acryloyloxyethyl) isocyanurate), 30 parts of tetrahydrofurfuryl acrylate, 1 as a photopolymerization initiator 3 parts of-(4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one was heated to 60 ° C. and mixed to obtain a comparative resin composition. The viscosity of this resin composition was 134 mPa · s. The refractive index (25 ° C.) of the resin layer obtained in the same manner as in Example 1 was 1.52.
From this result, it can be seen that the composition of Comparative Example 1 has a lower refractive index than the composition of the present invention, and is not suitable for the production of the lenses of the present invention.

Comparative Example 2
According to Example 1 of Patent Document 3 (Patent No. 3209554), urethane acrylate of Synthesis Example 1 of this document (reaction production of polyester diol of neopentyl glycol and adipic acid, ethylene glycol, tolylene diisocyanate and 2-hydroxyethyl acrylate) And 30 parts of the above urethane acrylate, 15 parts of the above o-phenylphenol diethoxyacrylate, and KAYARAD R-551 (bisphenol). A tetraethoxydiacrylate), 10 parts tribromophenyl acrylate, and 3 parts Irgacure 184 (1-hydroxycyclohexyl phenyl ketone) were heated to 60 ° C. and mixed to obtain a comparative resin composition. . The viscosity of this resin composition was 4420 mPa · s. Further, the refractive index (25 ° C.) of the resin layer obtained in the same manner as in Example 1 was 1.574.
From this result, it can be seen that the composition of Comparative Example 2 has a higher viscosity than the composition of the present invention, and is not suitable for fine processing and continuous processing of roll-shaped sheets and films.

In addition, the synthesis examples 1 and 3 of patent document 3 are shown below.
Synthesis Example 1 (Patent Document 3)
Polyester diol (neopentyl glycol and adipic acid polyester diol, molecular weight 2000, OH value 56.1) 120 parts, ethylene glycol 2.48 parts, tolylene diisocyanate 34.8 parts The mixture was heated and reacted at 80 ° C. for 10 hours, and then 24.4 parts of 2-hydroxyethyl acrylate and 0.1 part of methoquinone were charged and reacted at 80 ° C. for 10 hours to obtain urethane acrylate. Obtained.

Synthesis Example 3 (Patent Document 3)
258 parts of a compound represented by the following formula

(Manufactured by Sanyo Chemical Co., Ltd., reaction product of 1 mole of O-phenylphenol and 2 moles of ethylene oxide, product name, new-pole OPE-20, OH value 217.5), acrylic acid 86.5 parts Then, 300 parts of toluene, 21 parts of sulfuric acid and 5 parts of hydroquinone were charged, heated, and the produced water was distilled together with the solvent, condensed, and cooled to produce 18 parts of water in a separator, and the reaction mixture was cooled. The reaction temperature was 130-140 ° C. The reaction mixture is dissolved in 500 parts of toluene, neutralized with a 20% aqueous NaOH solution, and then washed three times with 100 parts of a 20% aqueous NaCl solution. The solvent was distilled off under reduced pressure to obtain 303 parts of a compound (liquid) represented by the following formula. The viscosity (25 ° C.) was 204 CPS, and the refractive index (23 ° C.) was 1.567.

(Wherein R ₁ is H or CH ₃ and the average value of n is an integer of 1 to 5)

Comparative Example 3
According to Example 3 of Patent Document 4 (Patent No. 3454544), 100 parts of the compound of Example 1 of this document and 3 parts of hydroxycyclohexyl phenyl ketone were heated to 60 ° C. and mixed to obtain a comparative resin composition. It was. The viscosity of this resin composition was 20000 mPa · s or more. The refractive index (25 ° C.) of the resin layer obtained in the same manner as in Example 1 was 1.619. From this result, it can be seen that the composition of Comparative Example 3 has a higher viscosity than the composition of the present invention, and is unsuitable for fine processing and continuous processing of roll-shaped sheets and films. Furthermore, when mold release evaluation was performed, resin adhered to the mold and it was difficult to release (×).

In addition, Example 1 of patent document 4 is shown below.
Example 1 (Patent Document 4)
3,4,5,6-Dibenzo-1,2-oxaphosphan-2-oxide (product name SANKO-, manufactured by Sanko Chemical Co., Ltd.) was added to a 2 L reactor equipped with a stirrer, thermometer, and water separator with condenser. 432 g of HCA) was charged, gradually heated to 120 ° C. and melted, and then 72 g of paraformaldehyde was gradually charged with stirring and reacted at a temperature of 120 to 125 ° C. for 3 hours. After confirming the absence of 3,4,5,6-dibenzo-1,2-oxaphosphan-2-oxide in the reaction solution by liquid chromatography, cool to room temperature and charge 500 g of 20% caustic soda. Dissolve in Thereafter, 15% hydrochloric acid is stirred and gradually charged until it becomes weakly acidic to precipitate crystals. Next, the crystals were filtered and washed with water, followed by filtration and drying to obtain 380 g of white crystals having a melting point of 165 ° C.
From the results of mass spectrum and ¹³ C-nuclear magnetic resonance (NMR), it was found that the obtained crystal was a compound having a structure represented by the following formula.

Next, 369 g of the obtained crystal, 216 g of acrylic acid, 600 g of toluene, 2.2 g of methoquinone, 21.6 g of PTS (p-toluenesulfonic acid), 1 L equipped with a stirrer, thermometer and water separator with condenser The reactor was charged and subjected to dehydration condensation reaction at 105-110 ° C. for 13 hours. The resulting reaction solution was washed twice with 10% aqueous sodium carbonate and once with 20% brine, and then toluene was distilled under reduced pressure. 303 g of a slightly yellow liquid was obtained. This had a viscosity at 40 ° C. of 6300 CPS and a refractive index at 20 ° C. of 1.6145.
From the results of mass spectrum and ¹³ C-nuclear magnetic resonance (NMR), it was found that the obtained viscous liquid was an acrylate ester having the following structure.

Comparative Example 4
In Example 1, a comparative resin composition was obtained in the same manner as in Example 1 except that 77 parts of o-phenylphenol monoethoxyacrylate was used as component (A) and component (B) was not used. The viscosity of this resin composition was 753 mPa · s. The refractive index (25 ° C.) of the resin layer obtained in the same manner as in Example 1 was 1.595. Flame retardancy: x.

As is clear from the evaluation results of Examples 1 to 8 and Comparative Examples 1 to 4, the resin composition of the present invention having a specific composition has a low viscosity, releasability, mold reproducibility, and adhesion to a substrate. The cured product has a high refractive index and a glass transition temperature (Tg) of 50 ° C. or higher. Therefore, it is suitable for an optical lens sheet having a fine structure, such as a Fresnel lens, a lenticular lens, a prism lens, and a microlens. In particular, it is suitable for applications that require fine processing and manufacturing that includes processes that require continuous processing.

The ultraviolet curable resin composition of the present invention and the cured product thereof are particularly suitable mainly for optical lens sheets such as Fresnel lenses, lenticular lenses, prism lenses, and micro lenses.

Claims

Monoacrylate monomer (A) having phenyl ether group, general formula (1)
A compound represented by formula (B)

(In the formula, R represents a hydrogen atom or a methyl group.)
And an energy ray curable resin composition for an optical lens sheet, comprising a photopolymerization initiator (C).
Monoacrylate monomers (A) having phenyl ether groups are o-phenylphenol (poly) ethoxy (meth) acrylate, p-phenylphenol (poly) ethoxy (meth) acrylate, o-phenylphenol epoxy (meth) acrylate, p- The resin composition according to claim 1, which is phenylphenol epoxy (meth) acrylate.
The resin composition according to claim 1 or 2, further comprising a (meth) acrylate compound (D) other than the monoacrylate monomer (A) having a phenyl ether group and the compound (B) represented by the general formula (1). .
The resin composition according to claim 3, wherein the (meth) acrylate compound (D) is a compound having a structure containing a bisphenol A skeleton.
The resin composition according to any one of claims 1 to 4, wherein the viscosity at 25 ° C measured with an E-type viscometer is 3000 mPa · s or less.
Hardened | cured material whose refractive index in 25 degreeC obtained by hardening | curing the resin composition as described in any one of Claims 1 thru | or 5 is 1.55 or more.
An optical lens sheet using the cured product according to claim 6.