JP2020158591A - Curable resin composition, cured product, and optical member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable resin composition, a cured product and an optical member. SOLUTION: A di (meth) acrylate (A) (component A) having a fluorene skeleton represented by the formula (1), a monofunctional (meth) acrylate (B) (component B) having a hydroxyl group and a plurality of aromatic rings. ), A (meth) acrylate (C) (C component) different from the A component and the B component, an antistatic agent (D) (D component), and a polymerization initiator (E) (E component). Curable resin composition. [Selection diagram] None

Description

The present invention relates to curable resin compositions, cured products and optical members.

Di (meth) acrylate having a bisarylfluorene skeleton is a material having high transmittance, refractive index, glass transition temperature, and scratch resistance. For this reason, applications to lenses, hard coats, antireflection films, imprint materials, and the like have been proposed.

For example, Patent Document 1 describes a fluorene compound having a polymerizable unsaturated bond, a non-fluorene (meth) acrylic monomer having at least one functional group selected from a hydroxyl group and a carboxyl group, and a hydroxyl group and a carboxyl group. Because the cured film of the curable composition containing a non-fluorene-based (meth) acrylic monomer having no group and another polymerization component composed of it has a high refractive index, high hardness, and excellent adhesion to a substrate. , It is disclosed that it is suitable for an optical material.

Japanese Unexamined Patent Publication No. 2012-224845

However, since the cured film described in Patent Document 1 has poor antistatic properties, there is a concern that dust and dirt may easily adhere to the surface. In the curable composition described in Patent Document 1, since the antistatic agent has poor solubility, it is difficult to obtain an antistatic effect by blending the antistatic agent.

The present invention has been made in view of the above circumstances, and is a curable resin composition capable of producing a cured product having high transparency and refractive index and excellent antistatic property, a cured product obtained by curing the cured product, and an optical member. The purpose is to provide.

（式（１）中、Ｚ^１、Ｚ^２は、各々独立に、芳香族炭化水素環を示す。Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、各々独立に、水素原子またはメチル基を示し、ｍは０〜５の整数を示し、ｎは０〜５の整数を示す。）
［２］前記Ｂ成分が、フェニルフェニル基、フェノキシフェニル基、ベンジルフェニル基及びクミルフェニル基からなる群から選ばれる少なくとも一種の芳香環を含む官能基を有する単官能の（メタ）アクリレートである、［１］に記載の硬化性樹脂組成物。
［３］前記Ｂ成分が、下記式（２）で表される単官能の（メタ）アクリレートである、［１］または［２］に記載の硬化性樹脂組成物。

（式（２）中、Ｒ^５は、水素原子またはメチル基を示す。Ｒ^６は、１つ以上の水素原子が水酸基で置換された炭素数１〜６のアルキレン基である。）
［４］前記Ｄ成分が、イオン性界面活性剤である、［１］〜［３］のいずれか１つに記載の硬化性樹脂組成物。
［５］［１］〜［４］のいずれか１つに記載の硬化性樹脂組成物を硬化した硬化物。
［６］［５］に記載の硬化物を含む光学部材。 The present invention includes the following [1] to [6].
[1] Di (meth) acrylate (A) (component A) having a fluorene skeleton represented by the following formula (1), monofunctional (meth) acrylate (B) (component B) having a hydroxyl group and a plurality of aromatic rings. ), A (meth) acrylate (C) (C component) different from the A component and the B component, an antistatic agent (D) (D component), and a polymerization initiator (E) (E component). Curable resin composition.

(In formula (1), Z ¹ and Z ² each independently represent an aromatic hydrocarbon ring. R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group. , M indicates an integer from 0 to 5, and n indicates an integer from 0 to 5.)
[2] The component B is a monofunctional (meth) acrylate having a functional group containing at least one aromatic ring selected from the group consisting of a phenylphenyl group, a phenoxyphenyl group, a benzylphenyl group and a cumylphenyl group. 1] The curable resin composition according to 1.
[3] The curable resin composition according to [1] or [2], wherein the component B is a monofunctional (meth) acrylate represented by the following formula (2).

(In the formula (2), R ⁵ represents a hydrogen atom or a methyl group. R ⁶ is an alkylene group having 1 to 6 carbon atoms in which one or more hydrogen atoms are substituted with hydroxyl groups.)
[4] The curable resin composition according to any one of [1] to [3], wherein the D component is an ionic surfactant.
[5] A cured product obtained by curing the curable resin composition according to any one of [1] to [4].
[6] An optical member containing the cured product according to [5].

According to the present invention, it is possible to provide a curable resin composition capable of obtaining a cured product having high transparency and refractive index and excellent antistatic property, a cured product obtained by curing the cured product, and an optical member.

The definitions of the following terms apply throughout the specification and claims.
"(Meta) acrylic" is a general term for acrylic and methacrylic.
"(Meta) acrylate" is a general term for acrylate and methacrylate.
"(Meta) acryloyl group" is a general term for acryloyl group and methacryloyl group, and the general formula CH ₂ = C (R) -C (= O)-[R represents a hydrogen atom or a methyl group. ] Is represented.
"~" Indicating a numerical range means that the numerical values described before and after the numerical range are included as the lower limit value and the upper limit value.

[Curable resin composition]
The curable resin composition of the present embodiment is a di (meth) acrylate (A) (component A) having a fluorene skeleton represented by the formula (1), a monofunctional (meth) having a hydroxyl group and a plurality of aromatic rings. Acrylate (B) (B component), (meth) acrylate (C) (C component) different from the A component and the B component, antistatic agent (D) (D component), and polymerization initiator (E) ( E component) is contained.
Hereinafter, each component contained in the curable resin composition according to the present invention will be described.

(Component A)
The component A is a di (meth) acrylate having a fluorene skeleton represented by the following formula (1), and is a component that improves the refractive index and the glass transition point of the cured product.

（式（１）中、Ｚ^１、Ｚ^２は、各々独立に、芳香族炭化水素環を示す。Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、各々独立に、水素原子またはメチル基を示し、ｍは０〜５の整数を示し、ｎは０〜５の整数を示す。）

(In formula (1), Z ¹ and Z ² each independently represent an aromatic hydrocarbon ring. R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group. , M indicates an integer from 0 to 5, and n indicates an integer from 0 to 5.)

In formula (1), Z ¹ and Z ² each independently represent an aromatic hydrocarbon ring. Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, an indene ring, an anthracene ring and the like. Benzene rings are preferable for Z ¹ and Z ^{2 in} that the compatibility with the component A is good.

In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group. From the viewpoint of further increasing the refractive index of the cured product, R ¹ , R ² , R ³ and R ⁴ are preferably hydrogen atoms.

In the formula (1), m represents an integer of 0 to 5, and n represents an integer of 0 to 5. When m and n are integers of 5 or less, the refractive index and the glass transition point of the cured product are high. Since the viscosity of the curable resin composition becomes a value suitable for moldability and the moldability is improved, m and n are preferably integers of 1 to 2, respectively.

A commercially available product can be used as the component A. As a commercially available product of component A, "trade name:" manufactured by Osaka Gas Chemical Co., Ltd., in which R ¹ , R ² , R ³ , and R ⁴ are all hydrogen atoms and m and n are all 1 compounds. Examples thereof include "Ogsol EA-0200" and "Product name: NK ester A-BPEF" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.
These A components may be used alone or in combination of two or more.

The content of the component A is preferably 25% by mass or more and 85% by mass or less, and more preferably 35% by mass or more and 75% by mass or less, based on 100% by mass of the total amount of the A component, the B component and the C component. .. By increasing the content of component A, the refractive index and glass transition point of the cured product can be increased. By reducing the content of component A, the viscosity of the curable resin composition can be lowered.

(B component)
The component B is a monofunctional (meth) acrylate having a hydroxyl group and a plurality of aromatic rings, and is a component that improves the solubility of the antistatic agent which is the component D.
Examples of the plurality of aromatic rings include a phenylphenyl group, a phenoxyphenyl group, a benzylphenyl group, a cumylphenyl group and the like. A phenylphenyl group is preferable because the refractive index of the cured product can be increased.

As the component B, a monofunctional (meth) acrylate represented by the following formula (2) is particularly preferable.

（式（２）中、Ｒ^５は、水素原子またはメチル基を示す。Ｒ^６は、１つ以上の水素原子が水酸基で置換された炭素数１〜６のアルキレン基である。）

(In the formula (2), R ⁵ represents a hydrogen atom or a methyl group. R ⁶ is an alkylene group having 1 to 6 carbon atoms in which one or more hydrogen atoms are substituted with hydroxyl groups.)

In formula (2), R ⁵ represents a hydrogen atom or a methyl group. R ⁶ is an alkylene group having 1 to 6 carbon atoms in which one or more hydrogen atoms are substituted with hydroxyl groups. Examples of the structure of R ⁶ include a hydroxymethylene group, a hydroxyethylene group, a hydroxypropylene group, a hydroxybutylene group, a hydroxypentylene group, a hydroxyhexylene group and the like. Since the solubility of the D component is improved, R ⁵ is a hydrogen atom, R ⁶ is preferably a hydroxy propylene group.
These B components may be used alone or in combination of two or more.

The content of the B component is preferably 1% by mass or more and 40% by mass or less, and more preferably 3% by mass or more and 30% by mass or less, based on 100% by mass of the total amount of the A component, the B component and the C component. .. By increasing the content of the B component, the solubility of the D component becomes good, and the transparency of the cured product is improved. By reducing the content of the B component, the viscosity of the curable resin composition can be lowered.

(C component)
The C component is a (meth) acrylate (C) other than the B component, and is a component that adjusts the viscosity of the curable resin composition and the glass transition point of the cured product. Examples of the C component include a monofunctional (meth) acrylate having one (meth) acryloyl group and a polyfunctional (meth) acrylate having two or more (meth) acryloyl groups.

Specific examples of the monofunctional (meth) acrylate include (meth) acrylic acid, 2- (meth) acryloyloxyethyl succinate, 2- (meth) acryloyloxyethyl maleate, and 2- (meth) phthalate. (Meta) acrylate containing a carboxyl group such as acryloyloxyethyl, 2- (meth) acryloyloxyethyl, etc .; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (Meta) acrylate having a hydroxyl group such as (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) Alkyl (meth) such as acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, and stearyl (meth) acrylate. ) Acrylate; cyclohexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, adamantyl (meth) acrylate (Meta) acrylate having an alicyclic structure such as phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene Glycol (meth) acrylate, phenoxypolypropylene glycol (meth) acrylate, phenylphenyl (meth) acrylate, phenylphenoxyethyl (meth) acrylate, phenoxybenzyl (meth) acrylate, phenylbenzyl (meth) acrylate, naphthyl (meth) acrylate, ( Has an aromatic ring structure such as 1-naphthyl) methyl (meth) acrylate (meth) ) Acrylate; (meth) acrylate containing a heterocyclic structure such as tetrahydrofurfuryl (meth) acrylate, glycidyl (meth) acrylate, (meth) acryloylmorpholine; methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, Apropyl (meth) acrylates such as butoxyethyl (meth) acrylates; 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxipropyltriethoxysilane, 2- (meth) acryloyloxyethyl acid phosphate, Examples thereof include trifluoroethyl (meth) acrylate and heptadecafluorodecyl (meth) acrylate.

Specific examples of the polyfunctional (meth) acrylate include, for example, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, and 1,6-hexanediol di (meth) acrylate. , Alkylene glycol di (meth) acrylate such as 1,9-nonanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyalkylene such as polybutylene glycol di (meth) acrylate. Glycoldi (meth) acrylate, neopentyl glycol di (meth) acrylate, tricyclodecanedimethanol di (meth) acrylate, polycarbonate diol di (meth) acrylate, polyester diol di (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate ) Bifunctional (meth) acrylates such as acrylates, propoxylated bisphenol A di (meth) acrylates, polyurethane di (meth) acrylates; trimethylol propanetri (meth) acrylates, tri (meth) acrylates of ethoxylated isocyanurates, ε- Trifunctional (meth) acrylates such as caprolactone-modified tris ((meth) acloxyethyl) isocyanurate; tetrafunctional (meth) acrylates such as ditrimethylolpropantetra (meth) acrylate; dipentaerythritol penta (meth) acrylate and the like. 5 Functional (meth) acrylates; 6-functional (meth) acrylates such as dipentaerythritol hexa (meth) acrylate can be mentioned.

A (meth) acrylate having an aromatic ring structure is preferable from the viewpoint of increasing the refractive index of the cured product, and in particular, phenylphenyl (meth) acrylate, phenylphenoxyethyl (meth) acrylate, and phenoxybenzyl having two or more benzene rings are preferable. (Meta) acrylate and phenylbenzyl (meth) acrylate are preferable. From the viewpoint that the glass transition point of the cured product can be increased, a polyfunctional (meth) acrylate is preferable, and a trifunctional or higher functional (meth) acrylate is particularly preferable.
These C components may be used alone or in combination of two or more.

The content of the C component is preferably 10% by mass or more and 70% by mass or less, more preferably 20% by mass or more and 60% by mass or less, based on 100% by mass of the total amount of the A component, the B component and the C component.
By increasing the content of the C component, the viscosity of the curable resin composition can be lowered. By reducing the content of the C component, the refractive index of the cured product can be increased.

(D component)
The component D is an antistatic agent, which is a component that lowers the surface low efficiency of the cured product and suppresses the adhesion of dust and dirt, and examples thereof include an ionic surfactant.
Specific examples of the ionic surfactant include a cationic antistatic agent such as "trade name: Electrostripper QN" of Kao Co., Ltd., and an anionic antistatic agent such as "trade name: Electrostripper ME-2". Antistatic agents, amphoteric antistatic agents such as "trade name: Electro stripper AC", non-ionic antistatic agents such as "trade name: Leodor TW-L120", "trade name: Emazole L-10V", etc. Can be mentioned. Anionic antistatic agents are particularly preferred because of their excellent antistatic performance and transparency.

The content of the D component is preferably 0.1% by mass or more and 5% by mass or less, more preferably 0.5% by mass or more and 3% by mass or less, based on 100 parts by mass of the total amount of the A component, the B component and the C component.
By increasing the content of the D component, the surface low efficiency of the cured product can be reduced. By reducing the content of the D component, the transparency of the cured product can be improved.

(E component)
The E component is a polymerization initiator, and examples thereof include a photopolymerization initiator, a thermal polymerization initiator, and a peroxide used for redox polymerization. The type of the E component can be appropriately selected depending on the polymerization method.

The photopolymerization initiator is a radical polymerization initiator used for photopolymerization. Specific examples of the photopolymerization initiator include benzophenone-type compounds such as benzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, methyl orthobenzoylbenzoate, and 4-phenylbenzophenone; t-butylanthraquinone, 2-ethyl. Anthraquinone-type compounds such as anthraquinone; 2-hydroxy-2-methyl-1-phenylpropan-1-one, oligo {2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone}, Benzyl dimethyl ketal, 1-hydroxycyclohexylphenyl ketone, benzoyl methyl ether, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-hydroxy-1- {4- [4- (2) -Hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one and other alkylphenone-type compounds; 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, Thioxanthone-type compounds such as diethylthioxanthone and isopropylthioxanthone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis (2,4) 6-trimethylbenzoyl) Acylphosphine oxide type compounds such as phenylphosphine oxide; phenylglycilate type compounds such as phenylglycolic acid methyl ester can be mentioned. Among these, alkylphenone-type compounds are preferable, and 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexylphenyl ketone are more preferable because they can suppress the coloring of the cured product. Further, the acylphosphine oxide type compound is preferable in that the inside of the cured product is sufficiently cured, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide is more preferable in that the coloring of the cured product can be suppressed.

The thermal polymerization initiator is a radical polymerization initiator used for thermal polymerization. Examples of the thermal polymerization initiator include organic peroxides and azo compounds.

Specific examples of the organic peroxide include ketone peroxides such as methyl ethyl ketone peroxide; 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (t-hexyl). Peroxyketars such as peroxy) cyclohexane and 1,1-di (t-butylperoxy) cyclohexane; 1,1,3,3-tetramethylbutylhydroperoxide, cumenehydroperoxide, p-menthan hydroperoxide Hydroperoxides such as dicumyl peroxides, dialkyl peroxides such as di-t-butyl peroxides; diacyl peroxides such as dilauroyl peroxides and dibenzoyl peroxides; di (4-t-butylcyclohexyl) peroxy Peroxydicarbonates such as dicarbonate and di (2-ethylhexyl) peroxydicarbonate; t-butylperoxy-2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxybenzoate, 1 , 1,3,3-Tetramethylbutylperoxy-2-ethylhexanoate and other peroxyesters.

Specific examples of the azo compound include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), and 2,2'-azobis (2,4-dimethylvaleronitrile). , 1,1'-azobis-1-cyclohexanecarbonitrile, dimethyl-2,2'-azobisisobutyrate, 4,4'-azobis-4-cyanovaleric acid, 2,2'-azobis- (2) -Amidinopropane) Dihydrochloride and the like.
Examples of the peroxide used for redox polymerization include dibenzoyl peroxide and hydroperoxide.

A redox-based polymerization initiator is usually used for redox polymerization. The redox-based polymerization initiator is a polymerization initiator in which a peroxide and a reducing agent are used in combination. When the above-mentioned peroxide is used as a redox-based polymerization initiator, an example of a combination with a reducing agent is as follows.

(1) Dibenzoyl peroxide (peroxide) and aromatics such as N, N-dimethylaniline, N, N-dimethyl-p-toluidine, N, N-bis (2-hydroxypropyl) -p-toluidine Combination with tertiary amines (reducing agent).
(2) Combination of hydroperoxide (peroxide) and metal soaps (reducing agent).
(3) Combination of hydroperoxide (peroxide) and thioureas (reducing agent).
These E components may be used alone or in combination of two or more.

The content of the E component is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass or less, based on 100 parts by mass of the total amount of the A component, the B component and the C component.

By increasing the content of the E component, the curability of the curable resin composition can be improved. By reducing the content of the E component, the transparency of the cured product can be improved.

(Other ingredients)
The curable resin composition of the present invention may contain other components other than the components A to E as long as the effects of the present invention are not impaired. Examples of other components include antioxidants, ultraviolet absorbers, chain transfer agents, rubbers, silica particles, zirconia, plasticizers, defoamers, rocking agents, mold release agents, fillers, pigments and the like. .. Other components may be used alone or in combination of two or more.

By containing an antioxidant, the curable resin composition of the present invention can improve the storage stability of the curable resin composition and suppress coloring due to oxidation of the cured product. Specific examples of the antioxidant include phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and the like.

Examples of phenolic antioxidants include 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, and n-octadecyl-3- (3', 5'-di-t-butyl). -4'-Hydroxyphenyl) propionate, tetrakis- [methylene-3- (3', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, triethylene glycol bis [3- (3-t) -Butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and the like.

Phosphorus-based antioxidants include triethyl phosphite, tri (2-ethylhexyl) phosphine, tridecylphosphine, triphenylphosphine, trisisodecylphosphine, tristridecylphosphite, and tris (2,4-di). -T-Butylphenyl) Phosphite and the like can be mentioned.

Sulfur-based antioxidants include dihexyl sulfide, dilauryl-3,3'-thiodipropionate, ditridecyl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, and disterial-3. , 3'-thiodipropionate, pentaerythritol tetrakis (β-laurylthiopropionate) and the like.

The curable resin composition of the present invention can improve weather resistance by containing an ultraviolet absorber. Specific examples of the ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-octyloxybenzophenone, 2-hydroxy-4-decyloxybenzophenone, 2-hydroxy-4,4'-dimethoxybenzophenone, 2-. Derivatives of 2-hydroxybenzophenone such as hydroxy-4,4'-dibutoxybenzophenone; 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'- Ditashaly butylphenyl) benzotriazoles or halides thereof; phenylsalicylate, p-tershaly butylphenylsalicylate, hydroxyphenyltriazine-based ultraviolet absorbers and the like can be mentioned.

The curable resin composition of the present invention can improve curability by containing a polyfunctional thiol as a chain transfer agent. Specific examples of the polyfunctional thiol include 1,4-bis (3-mercaptopropionyloxy) butane, 1,4-bis (3-mercaptobutylyloxy) butane, and tetraethylene glycol bis (3-mercaptopropionate). , Tetraethylene glycol bis (3-mercaptobutyrate), trimethylol ethanetris (3-mercaptopropionate), trimethylol ethanetris (3-mercaptobutyrate), trimethylol propanthris (3-mercaptopropionate) , Trimethylol Propantris (3-mercaptobutyrate), Tris-[(3-mercaptopropionyloxy) -ethyl] -isocyanurate, Tris-[(3-mercaptobutylyloxy) -ethyl] -isocyanurate, pentaerythritol Tetrakiss (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), dipentaerythritol hexakis (3-mercaptopropionate), dipentaerythritol hexakis (3-mercaptobutyrate), etc. Be done.

(Manufacturing method of curable resin composition)
Examples of the method for producing the curable resin composition include a method of stirring and mixing the components A to E at room temperature, a method of heating and mixing, and the like. When a thermosetting initiator is used as the E component, from the viewpoint of stability of the curable resin composition, a method of obtaining a curable resin composition by stirring and mixing at room temperature, or heating and mixing components other than the E component. After that, the mixture is cooled, the component E is added at room temperature, and the mixture is stirred and mixed to obtain a curable resin composition. When the curable resin composition is produced by heating and mixing, it is preferable to mix under heating at 40 ° C. to 100 ° C. from the viewpoint of good compatibility and more uniform mixing. From the same viewpoint, the stirring time at the time of mixing is preferably 0.1 hour to 5 hours.

(Viscosity of curable resin composition)
The viscosity of the curable resin composition is preferably in the range of 100 to 20,000 mPa · s, more preferably 200 to 15,000 mPa · s, as measured by a B-type viscometer at 23 ° C. More preferably, it is 300 to 10,000 mPa · s. When the viscosity of the curable resin composition is within the above range, good moldability can be obtained. If the viscosity of the curable resin composition is 100 mPa · s or more, resin leakage from the dispenser or the mold can be suppressed, and if it is 20,000 mPa · s or less, the penetrability into the mold and the workability at the time of liquid transfer are improved. It will be good.

<Action effect>
The curable resin composition of the present invention described above has a di (meth) acrylate (A) having a fluorene skeleton represented by (1) described above, a monofunctional (meth) acrylate having a hydroxyl group and a plurality of aromatic rings. It contains (B), a (meth) acrylate (C) different from the A component and the B component, an antistatic agent (D), and a polymerization initiator (E). The cured product obtained from the curable resin composition of the present invention is suitable as an optical member because it has high transparency, a high refractive index, and excellent antistatic properties.

<Cured product>
The cured product of the present invention can be obtained by curing the above-mentioned curable resin composition.
Examples of the method for obtaining a cured product include a method in which the curable resin composition according to the present invention has a predetermined shape and is cured to obtain a cured product having a predetermined shape. Examples of the method for obtaining a cured product having a predetermined shape in this way include a casting molding method in which a curable resin composition is poured into a mold, a liquid resin injection molding method (LIM method), a transfer molding method, and the like. Examples thereof include a coating method for coating a resin composition, an imprint molding method, and a potting molding method. Further, as a method for curing the curable resin composition, any one of photopolymerization, thermal polymerization and redox polymerization is adopted depending on the type of the polymerization initiator (C component) contained in the curable resin composition. it can.

When the curable resin composition is cured by photopolymerization to obtain a cured product, the wavelength of light irradiated to the curable resin composition is not particularly limited, but it is preferable to irradiate ultraviolet rays having a wavelength of 200 to 400 nm. Specific examples of the ultraviolet light source include ultra-high pressure mercury lamps, high pressure mercury lamps, metal halide lamps, high power metal halide lamps, UV-LED lamps, chemical lamps, black lights and the like. After photopolymerizing the curable resin composition, aftercure may be further performed. As a result, the amount of unreacted (meth) acryloyl groups remaining in the cured product can be reduced, and the strength of the cured product can be further increased. In addition, the coloring due to the decomposition product of the photopolymerization initiator can be faded. The aftercure conditions are preferably 0.5 to 24 hours at 70 to 150 ° C., more preferably 1 to 15 hours at 80 to 130 ° C.

When the curable resin composition is cured by thermal polymerization to obtain a resin for an optical member, the curing conditions are not particularly limited, but the curing temperature is 40 to 150 because it is easy to obtain a resin for an optical member with suppressed coloring. ℃ is preferable, and 60 to 130 ° C is more preferable. The curing time (heating time) when the curable resin composition is injected into a preheated mold and molded as in the LIM method or the transfer molding method varies depending on the curing temperature, but for example, the curing temperature is 100. In the case of ° C., 1 to 180 seconds is preferable, 1 to 120 seconds is more preferable, and 1 to 60 seconds is further preferable. On the other hand, the curing time when the curable resin composition is injected into a mold at room temperature and then heated as in the casting molding method varies depending on the curing temperature, but for example, when the curing temperature is 70 ° C., 5 minutes to 5 hours. Is preferable, and 10 minutes to 3 hours is more preferable.

After the thermosetting resin composition is thermally polymerized, it is preferable to further perform aftercure. As a result, the amount of unreacted (meth) acryloyl groups remaining in the cured product can be reduced, and the strength of the cured product can be further increased. The aftercure conditions are preferably 0.1 to 10 hours at 50 to 200 ° C., more preferably 0.2 to 5 hours at 70 to 150 ° C.

When the curable resin composition is cured by redox polymerization to obtain a cured product, it can be cured at room temperature of 5 to 40 ° C. by using a redox-based polymerization initiator. The curing temperature is preferably 15 to 40 ° C. from the viewpoint that the amount of unreacted (meth) acryloyl groups remaining in the obtained cured product can be reduced and the strength of the cured product can be further increased. In addition, since the curable resin composition is difficult to gel and can be handled stably, a method of dissolving a reducing agent in the curable resin composition in advance and adding a peroxide to the curable resin composition is used for curing. preferable.

(Transparency of cured product)
Regarding the transparency of the cured product, when the thickness of the cured product is 1 mm, the total light transmittance is preferably 88% or more and the haze is 2% or less, and the total light transmittance is 89% or more and the haze is 1. It is more preferably 5% or less, and further preferably the total light transmittance is 90% or more and the haze is 1% or less. The total light transmittance and the haze are values measured by the method described later.

(Refractive index of cured product (nD: D line (589 nm)))
The refractive index (nD: D line (589 nm)) of the cured product is preferably 1.58 or more, more preferably 1.59 or more, and further preferably 1.60 or more. When the refractive index of the cured product is 1.58 or more, the degree of freedom in the optical design of the optical member can be increased. The refractive index is a value measured by a method described later.

(Antistatic property of cured product)
Regarding the antistatic property of the cured product, if the surface resistivity of the cured product is “1 × 10 ¹⁴ Ω / □>”, it is possible to prevent dust and dirt from adhering to the surface of the cured product. The surface resistance value is a value measured by a method described later.

<Optical member>
The optical member of the present invention is produced by molding the above-mentioned cured product. Such molding may be performed after the curable resin composition is cured, or may be performed at the same time as the curing.

Optical members to which the optical molding material is applied include, for example, light emitting diode modules, mobile phones, smartphones, tablet terminals, wearable terminals, personal computers, cameras, organic electroluminescence (organic EL) devices, flat panel displays, touch panels, and electronic paper. , Photodiodes, phototransistors, solar cells, projectors, automobiles, lenses used in building materials, imprint materials, coating materials, optical diffraction grids, films, sheets, optical waveguides, encapsulants, adhesives, reflective materials, Examples include wavelength conversion materials and glass fiber reinforced plastics.

The cured product of the present invention is particularly useful as a lens such as a camera lens, an imprint material, or a coating material because it has high transparency, high refractive index, and excellent antistatic property.

<Lens>
Lenses cited as examples of the optical members of the present invention are provided in, for example, mobile phones, smartphones, tablet terminals, wearable terminals, personal computers, electronic devices such as digital cameras, automobile back cameras, drive recorders, driving support sensors, and the like. Used for camera modules. The lens of the present invention may be composed only of an optical molding material made of the cured product of the present invention, but may be formed on a transparent base material such as flat glass, curved glass or glass wafer, and on one or both sides of the transparent base material. It may be a hybrid lens made of the formed cured product of the present invention.

Examples of the lens molding method include a casting method in which a curable resin composition is sandwiched between upper and lower molds and then the resin is cured by heating or light irradiation to obtain a lens. Examples of the casting method include a method of molding individual lens pieces one by one, a wafer level method of molding a wafer on which a plurality of lens shapes are transferred, and then cutting out individual lens pieces.

<Imprint material>
The imprint material given as an example of the optical member of the present invention is used to impart a fine pattern to the surface of a base material, and can be used, for example, for patterning an antireflection film, a brightness improving film, or a semiconductor. The size of the fine pattern imparted by the imprint material is not particularly limited, and examples thereof include nanometer order, micrometer order, and millimeter order.

Examples of the base material include resin films such as PET film, TAC film, PEN film and COP film, resin sheets such as PMMA sheet and polycarbonate sheet, glass wafers and silicon wafers.
As a method for imparting a fine pattern, for example, a method in which the curable resin composition of the present invention is poured into a mold having an arbitrary fine structure, the curable resin composition is cured after contacting and pressurizing with a substrate, and the mold is removed. Alternatively, a method of pressing the mold against a portion where the curable resin composition of the present invention is poured onto a base material, then curing the curable resin composition, and removing the mold can be mentioned.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, "part" in each Example and comparative example means "part by mass". In addition, the measurement and evaluation in this example were carried out according to the following method.

[Evaluation method]
<Compatibility>
The appearance of the obtained curable resin composition was visually confirmed, and was marked with "◯" when there was no insoluble matter and "x" when there was insoluble matter.

<Viscosity>
The liquid temperature of the obtained curable resin composition was set to 23 ° C., and the viscosity was measured using a B-type viscometer.

<Measurement of total light transmittance and haze>
The total light transmittance and haze of the cured product having a diameter of about 50 mm and a thickness of about 1 mm were measured using a haze meter (trade name: HM-150 type, manufactured by Murakami Color Technology Research Institute).

<Measurement of refractive index>
The refractive index (nD: D line (589 nm)) of the cured product of about 6 mm × 35 mm × thickness 1 mm at 25 ° C. was measured with a multi-wavelength Abbe refractometer (trade name: DR-M2, manufactured by Atago). 1-Bromonaphthalene was used as an intermediate solution.

<Measurement of surface resistivity>
A cured product having a diameter of about 50 mm and a thickness of about 1 mm was stored at 23 ° C. and 50% RH for 24 hours, and then applied with a resistivity meter (trade name: Hiresta UP <MCP-HT450 type>, manufactured by Mitsubishi Chemical Analytech). The surface resistivity at a voltage of 1000 V was measured to evaluate the antistatic property. When the measured value was "1 x 10 ¹⁴ Ω / □ <", the evaluation result was described as "1 x 10 ¹⁴ Ω / □ <".

<Example 1>
In a reaction vessel equipped with a cooler, as component A, "trade name: NK ester A-BPEF" manufactured by Shin-Nakamura Chemical Industry Co., Ltd. (in the above general formula (1), R ¹ , R ² , R ³ , R ⁴ 65 parts of di (meth) acrylate having a fluorene skeleton in which all of them are hydrogen atoms and m and n are both 1, and 2-hydroxy-o-phenylphenolpropyl acrylate (Shin-Nakamura Chemical Industry Co., Ltd.) as B component. 10 parts of "trade name: NK ester 401P" manufactured by Kyoeisha, 25 parts of m-phenoxybenzyl acrylate ("trade name: light acrylate POB-A" manufactured by Kyoeisha Chemical Co., Ltd.) as C component, and Kao as D component. Add 1 part of "trade name: Electro stripper ME-2" manufactured by the company and 2 parts of 1-hydroxycyclohexylphenyl ketone ("trade name: IRGACURE184" manufactured by BASF) as the polymerization initiator (E) at 70 ° C. Stirring for 2 hours gave a curable resin composition.

<Preparation of cured product>
The obtained curable resin composition was sandwiched between two glass plates using a 1 mm thick silicone sheet as a gasket, irradiated with ultraviolet rays having an integrated light amount of 3000 mJ / cm ² with a high-pressure mercury lamp, and then photopolymerized, and then photopolymerized at 100 ° C. Was heated for 30 minutes. After cooling, the plate glass was removed to obtain a cured product having a diameter of about 50 mm and a thickness of about 1 mm, which was used for measuring the total light transmittance, haze, and surface low efficiency. By the same method, a 1 mm thick silicone sheet cut out from a rectangular shape of about 6 mm × 35 mm was used as a gasket to obtain a cured product of about 6 mm × 35 mm × 1 mm thick used for measuring the refractive index.
Using the obtained resin for optical members, the total light transmittance, haze, refractive index and surface low efficiency were measured by the above method. The results are shown in Table 1. The unit of each component in Table 1 is "part".

[Examples 2 to 10]
A curable resin composition and a cured product were prepared and evaluated in the same manner as in Example 1 except that the composition was changed to that shown in Table 1. The results are shown in Table 1.
[Comparative Examples 1 to 3]
A curable resin composition and a cured product were prepared and evaluated in the same manner as in Example 1 except that the composition was changed to that shown in Table 1. The results are shown in Table 1.

Details of each component described in Table 1 are described below.
NK ester A-BPEF: In the above general formula (1), di (meth) having a fluorene skeleton in which all of R ¹ , R ² , R ³ , and R ⁴ are hydrogen atoms and m and n are all 1. ) Acrylate ("Product name: NK ester A-BPEF" manufactured by Shin Nakamura Chemical Industry Co., Ltd.)
-NK Ester 401P: 2-Hydroxy-o-phenylphenol propyl acrylate ("trade name: NK Ester 401P" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.),
-Light acrylate POB-A: m-phenoxybenzyl acrylate ("trade name: light acrylate POB-A" manufactured by Kyoeisha Chemical Co., Ltd.),
NK Ester A-LEN-10: o-Phenylphenoxyethyl Acrylate (“Product Name: NK Ester A-LEN-10” manufactured by Shin-Nakamura Chemical Industry Co., Ltd.,
-Viscoat # 160: Benzyl acrylate ("Product name: Viscote # 160" manufactured by Osaka Organic Chemical Co., Ltd.)
-TMPTMA: Trimethylolpropane trimethacrylate ("Product name: Acriester TMP" manufactured by Mitsubishi Chemical Corporation)
-DPHA: Dipentaerythritol penta and hexaacrylate ("Product name: KAYARAD DPHA" manufactured by Nippon Kayaku Co., Ltd.)
-Miramer M340: Pentaerythritol triacrylate ("Product name: Miramer M340" manufactured by MIWON)
-Electro Stripper ME-2: Anionic Surfactant ("Product Name: Electro Stripper ME-2" manufactured by Kao Corporation)
-Electro Stripper QN: Cationic Surfactant (Kao Corporation "Product Name: Electro Stripper QN")
-IRGACURE184: 1-Hydroxycyclohexylphenylketone ("trade name: IRGACURE184" manufactured by BASF)

From Table 1, the curable resin compositions obtained in each example had good compatibility, and the cured product had high transparency, refractive index, and antistatic property. On the other hand, in Comparative Example 1 in which the D component was not blended and Comparative Example 2 in which the B component and the D component were not blended, the antistatic property was low. Comparative Example 3 in which the B component was not blended had poor compatibility.

Claims (6)

Di (meth) acrylate (A) (component A) having a fluorene skeleton represented by the following formula (1), monofunctional (meth) acrylate (B) (component B) having a hydroxyl group and a plurality of aromatic rings, described above. A curable resin containing a (meth) acrylate (C) (C component) different from the A component and the B component, an antistatic agent (D) (D component), and a polymerization initiator (E) (E component). Composition.

(In formula (1), Z ¹ and Z ² each independently represent an aromatic hydrocarbon ring. R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group. , M indicates an integer from 0 to 5, and n indicates an integer from 0 to 5.) The first aspect of claim 1 is a monofunctional (meth) acrylate having a functional group containing at least one aromatic ring selected from the group consisting of a phenylphenyl group, a phenoxyphenyl group, a benzylphenyl group and a cumylphenyl group. The curable resin composition according to the above. The curable resin composition according to claim 1 or 2, wherein the component B is a monofunctional (meth) acrylate represented by the following formula (2).

(In the formula (2), R ⁵ represents a hydrogen atom or a methyl group. R ⁶ is an alkylene group having 1 to 6 carbon atoms in which one or more hydrogen atoms are substituted with hydroxyl groups.) The curable resin composition according to any one of claims 1 to 3, wherein the D component is an ionic surfactant. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 4. An optical member containing the cured product according to claim 5.