TW201704329A - Curable resin composition and method for producing same - Google Patents

Abstract

A curable resin composition (C) which is characterized by containing an inorganic oxide (A) and a polyfunctional (meth)acrylate (B), and which is also characterized in that: the content of the inorganic oxide (A) is 25-80% by weight; the total light transmittance of this curable resin composition is 90% or more; and relational expression (1) is satisfied. T ≥ 91 - 1.25 x W/100 (1) (In the formula, W represents the content (wt%) of the inorganic oxide (A) in the curable resin composition; and T represents the total light transmittance (%) of the curable resin composition).

Description

Curable resin composition and method of producing the same

The present invention relates to a curable resin composition and a method of producing the same. Specifically, it relates to a curable resin composition which provides a cured product which is excellent in transparency and has high hardness, and a method for producing the same.

In recent years, display devices such as liquid crystal displays and touch panel displays having a film having a hard coat film as a protective layer on the surface thereof are rapidly spreading. In particular, an electronic device including a touch panel that operates by directly touching a screen with a finger or a pen, such as a smart phone or a tablet terminal, is remarkably popular, and the hardness of the surface of the touch panel is required to be improved in such a device. As a material of the touch panel, it is preferable to use a resin such as PET or acrylic which is safer and lighter than glass, but the disadvantage is that the resins are inferior in hardness to glass.

For this reason, a method of forming a hard coat layer containing an active energy ray-curable resin having a high hardness of cerium oxide fine particles as a filler as a main component is known, but it is difficult to use as an inorganic substance as an active energy of an organic substance. Since the monomer of the wire-hardening resin is uniformly dispersed, a method of improving the dispersibility by organically treating the surface of the cerium oxide fine particles can be employed (Patent Documents 1 to 3).

However, the ultraviolet curable resin composition produced by the method exists as follows Problem: From the viewpoint of the transparency of the cured product, the content of the cerium oxide particles is limited, and the desired film hardness cannot be obtained.

Patent Document 1: Japanese Patent Laid-Open Publication No. 2000-264621

Patent Document 2: JP-A-2015-86103

Patent Document 3: Japanese Laid-Open Patent Publication No. 2015-36402

An object of the present invention is to provide a curable resin composition which can provide a cured product having excellent transparency and high hardness, and a method for producing the same.

The present inventors conducted research in order to achieve the above object, and as a result, completed the present invention.

In other words, the present invention relates to a method for producing a curable resin composition (C) and a curable resin composition (C), which comprises an inorganic oxide (A) and a polyfunctional compound. The (meth) acrylate (B), the content of the inorganic oxide (A) is 25 to 80% by weight, and the total light transmittance of the curable resin composition is 90% or more, and the following relation (1) is satisfied; The method for producing a curable resin composition (C) is a method for producing a curable resin composition (C) comprising an inorganic oxide (A) and a polyfunctional (meth) acrylate (B), which comprises the following steps : in the polyfunctional (meth) acrylate (B), in the presence of the catalyst (b), selected from the group consisting of inorganic alkoxides (a1), metal mineral acid salts (a2) and inorganic chlorides (a3) One or more inorganic oxide precursors (a) of the group are reacted with water to obtain inorganic oxidation (A).

T≧91-1.25×W/100 (1)

[In the formula, W represents the content (% by weight) of the inorganic oxide (A) in the curable resin composition, and T represents the total light transmittance (%) of the curable resin composition].

The curable resin composition of the present invention exhibits an effect of providing a cured product having excellent transparency and high hardness. The curable resin composition of the present invention can provide a cured product having high hardness even if it contains a large amount of fine particles of an inorganic oxide such as cerium oxide. According to the method for producing a curable resin composition of the present invention, a curable resin composition capable of providing a cured product having excellent transparency and high hardness can be produced.

The curable resin composition (C) of the present invention contains an inorganic oxide (A) and a polyfunctional (meth) acrylate (B), and the content of the inorganic oxide (A) is 25 to 80% by weight. The total light transmittance of the curable resin composition is 90% or more. The curable resin composition (C) of the present invention further satisfies the following relational expression (1).

T≧91-1.25×W/100 (1)

[wherein, W represents the content (% by weight) of the inorganic oxide (A) in the curable resin composition, and T represents the total light transmittance (%) of the curable resin composition]

From the viewpoint of the hardness of the cured product, examples of the inorganic oxide (A) include inorganic oxides such as cerium oxide, zirconium, titanium, lanthanum, zinc, aluminum, gallium, indium, antimony, and tin. The inorganic oxide (A) may be used alone or in combination of two or more.

The content of the inorganic oxide (A) in the curable resin composition (C) of the present invention is 25 to 80% by weight, preferably 30 to 70% by weight, from the viewpoint of the balance between the hardness and the transparency. Further, it is preferably 30 to 60% by weight. If it is less than 25% by weight, the hardness of the cured product is insufficient, and if it exceeds 80% by weight, the transparency of the cured product is deteriorated. When two or more compounds are contained in the inorganic oxide (A), the above content is defined as the total of these.

The inorganic oxide (A) preferably has a hydroxyl group, and the inorganic oxide (A) is preferably selected from the group consisting of inorganic alkoxide (a1), metal mineral acid salt (a2) and inorganic chloride (a3). More preferably, the hydrolysis condensate of the inorganic oxide precursor (a) is used as the hydrolysis condensate, more preferably in the polyfunctional (meth) acrylate (B), in the presence of the catalyst (b) Under the condition, one or more inorganic oxide precursors (a) selected from the group consisting of inorganic alkoxide (a1), metal mineral acid salt (a2), and inorganic chloride (a3) are reacted with water. Winner.

The polyfunctional (meth) acrylate (B) contained in the curable resin composition (C) of the present invention preferably has at least 2 (preferably 3 to 6) from the viewpoint of the hardness of the cured product. (poly)(meth)acrylate of (meth)acryloyl group.

Specific examples of the polyfunctional (meth) acrylate (B) include the following two (meth) acrylates (B1), trivalent or higher (meth) acrylates (B2), and polyesters ( Methyl) acrylate (B3), urethane (meth) acrylate (B4), epoxy (meth) acrylate (B5), (meth) propylene thiol modified butyl Diene polymer (B6), (methyl) Acryl fluorenyl modified dimethyl polyoxyalkylene polymer (B7).

The di(meth)acrylate (B1) may, for example, be a polyoxyalkylene (the number of carbon atoms of the alkyl group is 2 to 4) [the number average molecular weight is 106 or more and 3,000 or less (hereinafter, the number average molecular weight is Refers to the number average molecular weight measured by gel permeation chromatography (GPC), referred to as Mn)] bis (meth) acrylate (B11): polyethylene glycol (preferably Mn 100 ~ 800, better) It is Mn300~500), polypropylene glycol (preferably Mn100~500, more preferably Mn150~300) and polytetramethylene glycol (preferably Mn400~1000, more preferably Mn500~800). Methyl) acrylate.

Further, examples of the di(meth)acrylate (B1) include an alkylene oxide of a dihydric phenol compound (hereinafter, "alkylene oxide" is abbreviated as AO) (2 to 30 m). Di(meth)acrylate: dihydric phenol compound [monocyclic phenol (catechol, resorcin, hydroquinone, etc.), condensed polycyclic phenol (dihydroxynaphthalene, etc.), bisphenol compound AO adduct of (bisphenol A, -F or -S, etc.)] bis(meth) acrylate of dioxime oxirane (EO) 4 molar addition, dihydroxynaphthalene Dimethyl (meth) acrylate of propylene oxide (PO) 4 molar addition product, EO2 molar of bisphenol A, -F or -S, or PO4 molar addition product, etc. Base) acrylate.

Examples of the di(meth)acrylate (B1) include di(meth)acrylates of aliphatic diols having 2 to 30 carbon atoms: each of neopentyl glycol and 1,6-hexanediol ( Methyl) acrylate.

Examples of the di(meth)acrylate (B1) include a di(meth)acrylate of a condensed ring-containing diol having 6 to 30 carbon atoms: a di(methyl) group of dimethylol tricyclodecane. Acrylate, di(meth)acrylate of cyclohexanedimethanol and di(meth)acrylate of hydrogenated bisphenol A.

As the di(meth)acrylate (B1), a di(meth)acrylate of a polyhydric alcohol having 3 to 40 carbon atoms: trimethylolpropane EO3 molar addition di(meth)acrylate may also be mentioned. And a di(meth)acrylate having a hydroxyl group in a molecule such as pentaerythritol di(meth)acrylate.

Examples of the trivalent or higher (meth) acrylate (B2) include a poly(meth) acrylate having a carbon number of 3 to 40 and an AO adduct thereof: trimethylolpropane tri(methyl) Tris(meth)acrylate of acrylate, glycerol, EO3 molar of trimethylolpropane or tris(meth)acrylate of PO3 molar addition, EO3 molar of glycerol or PO3 molar addition Each of the three (meth) acrylates, tris(methyl) acrylate of neopentyl alcohol, tetra (meth) acrylate of neopentyl alcohol, and EO4 molar addition of pentaerythritol (meth) acrylate, tetrakis(meth) acrylate of dipentaerythritol, penta (meth) acrylate of dipentaerythritol, hexa (meth) acrylate of dipentaerythritol, two A hexa(meth) acrylate of an EO adduct of pentaerythritol, a pentoxide of an EO adduct of dipentaerythritol, or the like.

Further, as described below, the polyfunctional (meth) acrylate (B) preferably has a reactive group (α) which reacts with a hydroxyl group in the inorganic oxide (A) to form a chemical bond. Further, the trivalent or higher (meth) acrylate (B21) having a hydroxyl group as such a reactive group (α) in the molecule is exemplified by an ester reaction product of a polyhydric alcohol and acrylic acid or methacrylic acid. More than one hydroxyl.

Examples of the trivalent or higher (meth) acrylate (B21) having a hydroxyl group in the molecule include tris(methyl) acrylate of pentaerythritol; and EO adduct of neopentyl alcohol. (meth) acrylate; penta (meth) acrylate of dipentaerythritol, tetra (meth) acrylate of dipentaerythritol, tri (meth) acrylate of dipentaerythritol, two Penta(meth)acrylate of EO adduct of pentaerythritol; poly(meth)acrylate of tripentenol.

Further, in the reaction of a polyol with an ester of acrylic acid or methacrylic acid, it is generally not obtained that the chemical equivalent is uniform, but a polyfunctional (meth) acrylate having a different number of ester bonds (ie, the amount of a hydroxyl group) is obtained ( Mixture of B). For example, when 6 moles of acrylic acid is reacted with 6 moles of dipentaerythritol having 6 hydroxyl groups to produce hexaacrylate of dipentaerythritol, it is usually also produced as a by-product of a hydroxyl group. A pentaacrylate of a tetraol or a tetraacrylate of dipentaerythrol having two hydroxyl groups is a mixture of the above. As the polyfunctional (meth) acrylate (B) of the present invention, such a mixture can also be used.

The polyester (meth) acrylate (B3) may have a plurality of ester bonds and 5 obtained by esterification of a polyvalent carboxylic acid, a polyhydric alcohol, and an ester-forming (meth)acryl fluorenyl compound. One or more polyester (meth) acrylates having a Mn150 or more and a Mn of 4,000 or less.

Examples of the polyvalent carboxylic acid include an aliphatic polybasic carboxylic acid (for example, a reaction product of malonic acid, maleic acid (anhydride), adipic acid, sebacic acid, succinic acid, and an acid anhydride (dioxane) a reaction of a tetraol with maleic anhydride, etc.); an alicyclic polycarboxylic acid [e.g., cyclohexanedicarboxylic acid, tetrahydrophthalic acid (anhydride), methyltetrahydrophthalic acid (anhydride) And an aromatic polycarboxylic acid [for example, isophthalic acid, terephthalic acid, phthalic acid (anhydride)].

Examples of the polyhydric alcohol include ethylene glycol, 1,3-propanediol, and 1,4-butanediol.

Examples of the (meth)acrylonitrile-containing compound containing an ester-forming property include acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, and 2-hydroxyethyl methacrylate.

Examples of the amine ester (meth) acrylate (B4) include a plurality of amine ester bonds and two or more obtained by esterification of a polyisocyanate, a polyhydric alcohol, and a hydroxyl group-containing (meth) acrylate. Amino ester (meth) propylene having a (meth) propylene fluorenyl group of Mn 400 or more and Mn 5,000 or less Acid ester.

Examples of the polyisocyanate include aliphatic polyisocyanate [hexamethylene diisocyanate, etc.]; aromatic (fatty) polyisocyanate [2,4- or 2,6-methylphenylene diisocyanate, 1,5- Naphthalene diisocyanate, decyl diisocyanate, etc.; alicyclic polyisocyanate [isophorone diisocyanate, 4,4'-methylene bis(cyclohexyl isocyanate), etc.].

Examples of the polyhydric alcohol include ethylene glycol, 1,4-butanediol, neopentyl glycol, polyether polyol, polycaprolactone polyol, polyester polyol, polycarbonate polyol, and polytetrazol. Methyl glycol and the like.

Examples of the hydroxyl group-containing (meth) acrylate include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, neopentaerythritol tri(meth)acrylate, and dipentaerythritol. (Meth) acrylate, etc.

Examples of the epoxy (meth) acrylate (B5) include an epoxy having a Mn 400 or more and a Mn 5,000 or less obtained by a reaction of a polyvalent (two-tetravalent) epoxide and (meth)acrylic acid. Base) acrylate and the like.

Examples of the (meth)acrylonitrile-based modified butadiene polymer (B6) include polybutadiene poly(meth)acrylate having a (meth)acryl fluorenyl group in its main chain and/or side chain (Mn500). ~500,000) and so on.

As the (meth)acrylonitrile-modified dimethylpolysiloxane polymer (B7), a dimethyl group of Mn 300 to 20,000 having a (meth)acryl fluorenyl group in a main chain and/or a side chain may be mentioned. Oxyalkyl poly(meth) acrylate.

The above (B1) to (B7) may be used singly or in combination of two or more. Among these (B1) to (B7), from the viewpoint of the hardness of the cured product, it is preferably (B2) to (B7), and further preferably (B2) and (B4). Moreover, in terms of adhesion and flexibility, it can be used in combination Functional (meth) acrylate.

The polyfunctional (meth) acrylate (B) in the present invention more preferably contains a polyfunctional (meth) acrylate (B) having a reactive group (α) reactive with a hydroxyl group. The content of the polyfunctional (meth) acrylate having a reactive group (α) in the polyfunctional (meth) acrylate (B) is preferably 50 mol% or more, more preferably 90 mol% or more. In the present invention, the polyfunctional (meth) acrylate (B) is further preferably a polyfunctional (meth) acrylate (B) having a reactive group (α).

Examples of the reactive group (α) which can react with a hydroxyl group include a hydroxyl group, a carboxyl group, an amine group, a thiol group, a sulfonic acid group, a phosphoric acid group, and a decylamino group. Since the reactive group (α) reacts with a hydroxyl group in the inorganic oxide (A) to form a chemical bond at the organic-inorganic interface, it exhibits high hardness. Among these reactive groups (α), a hydroxyl group, a carboxyl group, a phosphoric acid group, and more preferably a hydroxyl group or a carboxyl group are preferred, and a hydroxyl group is preferred.

In the curable resin composition (C) of the present invention, it is preferred that the polyfunctional (meth) acrylate (B) contains a polyfunctional (meth) acrylate having a reactive group (α) reactive with a hydroxyl group. The inorganic oxide (A) has a hydroxyl group, and at least a part of the reactive group (α) in the polyfunctional (meth) acrylate (B) reacts with at least a part of the hydroxyl group in the inorganic oxide (A) to be chemically bonded.

Based on the total weight of the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) in the curable resin composition (C), polyfunctional (meth)acrylic acid from the viewpoint of hardness and transparency The content of the ester (B) is usually from 20 to 75% by weight, preferably from 25 to 70% by weight, more preferably from 30 to 60% by weight. When two or more compounds are contained in the polyfunctional (meth) acrylate (B), the above content is defined as the total of these.

The total light transmittance of the curable resin composition (C) of the present invention is 90%. on.

Further, the total light transmittance in the present invention is measured by total light transmittance in accordance with JIS-K7105 by sandwiching a sheet of a hardening resin composition as described in detail in the measurement method of the embodiment. The device takes measurements.

An object of the present invention is to provide a curable resin composition which can provide a cured product having high transparency and high hardness. However, if the content of the inorganic oxide (A) is increased in order to increase the hardness, the opposite is true. relationship.

Therefore, the curable resin composition (C) of the present invention satisfies the following relational expression (1) relating to the content of the inorganic oxide (A) and the total light transmittance of the curable resin composition.

T≧91-1.25×W/100 (1)

In the relation (1), W represents the content (% by weight) of the inorganic oxide (A) in the curable resin composition, and T represents the total light transmittance (%) of the curable resin composition.

As described above, in order to increase the hardness, it is necessary to make the content of the inorganic oxide high, but it is preferable to mix fine particles of a general inorganic oxide, for example, cerium oxide microparticles, into the polyfunctional (meth) acrylate (B). In the case of dispersion, for example, if the content of the cerium oxide fine particles is more than 25% by weight, the transparency tends to be impaired.

Therefore, in the production of the curable resin composition (C) of the present invention, it is preferred to include the following steps: in the polyfunctional (meth) acrylate (B), in the presence of the catalyst (b), One or more inorganic oxide precursors (a) of a group consisting of a free inorganic alkoxide (a1), a metal inorganic acid salt (a2), and an inorganic chloride (a3) are reacted with water to obtain an inorganic oxide. (A).

The inorganic oxide (A) contained in the curable resin composition (C) of the present invention is an inorganic oxide precursor (a) in the polyfunctional (meth) acrylate (B) as described above. When the reaction with water is carried out, the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) are excellent in compatibility. The curable resin composition contains the inorganic oxide (A) obtained in this manner, and thus the hardness of the cured product becomes high.

In addition, when the inorganic oxide (A) is obtained by the above method, the content of the inorganic oxide (A) in the curable resin composition (C) is 25 to 80% by weight, and the transparency of the cured product is obtained. Also excellent.

The curable resin composition (C) of the present invention is preferably used in the presence of the catalyst (b) to cause the inorganic oxide precursor (a) in the polyfunctional (meth) acrylate (B). The hydrolysis condensate of the inorganic oxide precursor (a) produced by the reaction of water is used as the inorganic oxide (A) instead of the inorganic oxide (A) and the polyfunctional (meth) acrylate (B). Manufacturing.

Further, the inorganic oxide (A) is preferably one or more inorganic oxide precursors selected from the group consisting of inorganic alkoxides (a1), metal mineral acid salts (a2), and inorganic chlorides (a3) ( A hydrolysis condensate of a). The inorganic oxidized condensate of the inorganic oxide precursor (a), that is, the inorganic oxide (A), is preferred because it usually has a hydroxyl group.

Examples of the inorganic alkoxide (a1) include a decane oxide, a zirconium alkoxide, a titanium alkoxide, a decane oxide, a zinc alkoxide, an aluminoxane, a gallium alkoxide, and an indium alkoxide. , decane oxide, tin alkoxide, and the like. These may be used alone or in combination of two or more.

Among these, from the viewpoint of hardness, a cerium oxide oxide, a titanium alkoxide, and a zirconium alkoxide are preferable. As the cerium oxide alkoxide, tetraethoxy decane or tetra-n-butoxy decane is preferable, and as the titanium alkoxide, tetraethoxy titanium or tetra-positive is preferable. Titanium butoxide.

Examples of the metal inorganic acid salt (a2) include a combination of a metal such as titanium or zirconium and a mineral acid such as nitric acid or sulfuric acid. Specific examples thereof include titanium tetranitrate, titanium oxysulfate, zirconyl nitrate, and zirconium sulfate. These may be used alone or in combination of two or more.

Among these, titanium tetranitrate, titanium oxysulfate, and zirconium oxynitrate are preferred. These may be used alone or in combination of two or more.

Examples of the inorganic chloride (a3) include metal chlorides and non-metal chlorides, and examples thereof include titanium tetrachloride, zirconium tetrachloride, hafnium tetrachloride, zinc chloride, aluminum chloride, and gallium chloride. Metal chlorides such as indium chloride and tin chloride; and non-metal chlorides such as antimony tetrachloride and antimony tetrachloride. These may be used alone or in combination of two or more.

Among these, a chloride such as ruthenium, titanium or zirconium is preferable, and specifically, ruthenium tetrachloride, titanium tetrachloride and zirconium tetrachloride are used.

Among the inorganic oxide precursors (a), an inorganic alkoxide (a1) is preferred.

The polyfunctional (meth) acrylate (B) used for the production of the inorganic oxide (A) is the same as the above polyfunctional (meth) acrylate (B). The polyfunctional (meth) acrylate (B) preferably contains a polyfunctional (meth) acrylate having a reactive group (α) reactive with a hydroxyl group, and further preferably has reactivity with a hydroxyl group. A polyfunctional (meth) acrylate of the group (α). In the polyfunctional (meth) acrylate (B) having a reactive group (α), in the presence of the catalyst (b), it is selected from the group consisting of inorganic alkoxides (a1) and metal mineral acid salts (a2). And one or more inorganic oxide precursors (a) in the group consisting of inorganic chlorides (a3) are reacted with water, whereby inorganic oxides (A) and polyfunctional (meth)acrylates can be produced. (B), multiple officials A curable resin composition capable of chemically bonding at least a part of the reactive group (α) in the (meth) acrylate (B) and at least a part of the hydroxyl group in the inorganic oxide (A). Such a curable resin composition can be preferably used as the curable resin composition (C) of the present invention.

The amount of the polyfunctional (meth) acrylate (B) used in the production of the inorganic oxide (A) is not particularly limited, and for example, relative to the inorganic oxide precursor (a) and the polyfunctional (meth) acrylate The total weight of (B) is preferably from 20 to 75% by weight, more preferably from 25 to 70% by weight, still more preferably from 30 to 60% by weight.

In the present invention, it is preferred to react the inorganic oxide precursor (a) with water in the presence of the catalyst (b). Examples of the catalyst (b) include an acid catalyst (b1) and a base. Catalyst (b2).

Among these, an acid catalyst (b1) is preferred. The amount of the catalyst (b) to be used may be appropriately selected depending on the type of the catalyst or the like. For example, it is preferably 0.1 to 15 parts by weight, more preferably 0.1 to 10 parts by weight based on 100 parts by weight of the inorganic oxide precursor (a). Parts by weight.

Examples of the acid catalyst (b1) include inorganic acids and organic acids, and examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and boric acid.

Examples of the organic acid include sulfonic acid (p-toluenesulfonic acid, etc.), carboxylic acid, hydroxy acid, and oxalic acid.

Examples of the alkali catalyst (b2) include metal hydroxides and organic amines. Examples of the metal hydroxides include sodium hydroxide, potassium hydroxide, and lithium hydroxide.

The organic amine may, for example, be an aliphatic amine, an alicyclic amine, an aromatic amine or a heterocyclic amine.

Examples of the aliphatic amine include hexylamine, octylamine, methylhexylamine, methyloctylamine, dimethylhexylamine, dimethyloctylamine, dimethyllaurylamine, and dimethyl-10- Alkyl group such as hexaamine The mono-, di- or tri-alkylamine having a carbon number of 1 to 18.

Examples of the alicyclic amine include a carbon number of a cycloalkyl group such as cyclobutylamine, cyclohexylamine, cyclopentylamine, cyclooctylamine, N-methylcyclohexylamine, and N-ethylcyclohexylamine. It is a 4 to 12 cycloalkylamine and these alkyl (carbon number 1 to 6) substituents.

The aromatic amine may, for example, be an aromatic amine having 6 to 18 carbon atoms such as aniline or diphenylamine.

The heterocyclic amine may, for example, be a heterocyclic amine having 4 to 10 carbon atoms such as phenylephrine.

It is preferred that the inorganic oxide precursor (a) and the water molar ratio (inorganic oxide precursor (a)/water) are produced as the inorganic oxide precursor (a). It is 2 to 200, more preferably 5 to 150, and still more preferably 10 to 100.

If the molar ratio is less than 2, the transparency of the cured product tends to be deteriorated, and if it exceeds 200, the hardness of the cured product tends to be insufficient.

In the above reaction, the water used for the hydrolysis of the inorganic oxide precursor (a) may be added at once, may be added in portions, or may be added dropwise.

The temperature at which the inorganic oxide (A) is produced by the above reaction is preferably 40 to 80 ° C, more preferably 60 to 70 ° C. If the temperature is 40 ° C or more, the reaction rate becomes faster, and productivity is improved. In addition, when it is 80 ° C or lower, the polyfunctional (meth) acrylate can be subjected to polycondensation of the hydrolyzate of the inorganic oxidation precursor (a) without polymerizing in the reaction system.

The reaction time in the production of the inorganic oxide (A) by the above reaction is preferably from 30 minutes to 6 hours, more preferably from 2 hours to 4 hours.

Since the curable resin composition (C) of the present invention has a total light transmittance of 90% or more, it is possible to provide a cured product excellent in transparency.

The cured product of the curable resin composition (C) of the present invention preferably has a haze value of 1% or less. If it exceeds 1%, the transparency of the cured product deteriorates.

Further, the haze value of the cured product is measured by a total light transmittance measuring device according to JIS-K7105, as detailed in the measuring method of the embodiment, by measuring the film of the cured film of the curable resin composition.

In the curable resin composition (C) of the present invention, the median diameter d of the particles of the inorganic oxide (A) as measured by dynamic light scattering is preferably from 1 to 100 nm, more preferably from 10 to 10. 50nm. When the median diameter d of the inorganic oxide (A) exceeds 100 nm, transparency and hardness may be deteriorated, and if it is less than 1 nm, the hardness of the cured product may be insufficient. When the curable resin composition (C) contains the inorganic oxide (A) having a median diameter d of the particles measured by a dynamic light scattering method within the above range, a cured product having high transparency and hardness can be formed.

The composition containing the inorganic oxide (A) may contain a polyfunctional (meth) acrylate (B) as a curable resin composition (C) which is polyfunctional (methyl) In the acrylate (B), in the presence of the catalyst (b), one selected from the group consisting of inorganic alkoxide (a1), metal mineral acid salt (a2), and inorganic chloride (a3) The above inorganic oxide precursor (a) is obtained by reacting with water. In addition, in order to ensure the transparency in the case where the content of the inorganic oxide (A) is increased, the same type as the polyfunctional (meth) acrylate (B) used in the production of the inorganic oxide (A) can be further added. The polyfunctional (meth) acrylate (B) or the different type (B) is diluted to obtain a curable resin composition (C). Further, after the reaction, the catalyst (b) may be removed from the composition containing the inorganic oxide (A) and the polyfunctional (meth) acrylate (B), or the catalyst (b) may be neutralized.

The energy used when the curable resin composition of the present invention is cured The source may be a heat, an electron beam, or an X-ray, which is hardened by the energy source, and further contains a photopolymerization initiator (D), whereby it is hardened by irradiation of light.

As the light at this time, ultraviolet rays, infrared rays, and visible rays can be used.

Among these, from the viewpoints of hardenability and resin deterioration, ultraviolet rays and electron beams are preferable. The curable resin composition (C) of the present invention is suitably used as an active energy ray-curable resin composition which is cured by an active energy ray (ultraviolet rays, electron beams, X-rays, etc.) as described above.

The curable resin composition (C) of the present invention preferably further contains a photopolymerization initiator (D).

The photopolymerization initiator (D) to be added to the curable resin composition (C) of the present invention includes a phosphine oxide compound (D1), a benzamidine compound (D2), and 9- Oxygen and sulfur Compound (D3), oxime ester compound (D4), hydroxybenzimidyl compound (D5), benzophenone compound (D6), ketal compound (D7), 1,3 alpha aminoalkane A benzophenone compound (D8) or the like.

Examples of the phosphine oxide-based compound (D1) include bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide and 2,4,6-trimethylbenzimidyl diphenyl. Phosphine oxide, 1,3,5-trimethylbenzimidyldiphenylphosphine oxide, and the like.

Examples of the benzamidine compound (D2) include methyl benzhydrazinecarboxylate.

9-oxosulfur Compound (D3), isopropyl 9-oxosulfide Wait.

Examples of the oxime ester compound (D4) include 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzylidenehydrazine), and ethyl ketone. (ethanone), 1-[9-ethyl-6 -(2-Methylbenzylidene)-9H-indazol-3-yl]-, 1(O-ethylindenyl) and the like.

Examples of the hydroxybenzimidyl compound (D5) include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, and benzoin alkyl ether.

Examples of the benzophenone-based compound (D6) include benzophenone and the like.

The ketal compound (D7) may, for example, be a benzyldimethylketal or the like.

Examples of the 1,3 α-aminoalkylphenone compound (D8) include 2-methyl-1-[4-(methylthio)phenyl]-2-N-. Morpholinopropan-1-one and the like.

In the photopolymerization initiator (D), from the viewpoint of pencil hardness, it is preferably (D1), (D5), (D8), and further preferably double (2, 4, 6-trimethyl). Benzobenzyl)-phenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-N- Lolinylpropan-1-one, 1,3,5-trimethylbenzimidyldiphenylphosphine oxide.

Based on the total weight of the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) in the curable resin composition (C), a photopolymerization initiator (from the viewpoint of hardenability and transparency) The content of D) is from 0.1 to 10% by weight, preferably from 0.2 to 7% by weight.

In the curable resin composition (C) of the present invention, one or two or more kinds of various additives may be contained as needed within the range which does not inhibit the effects of the present invention.

Examples of the additives include a plasticizer, an organic solvent, a dispersant, an antifoaming agent, a shake imparting agent (tackifier), a slipping agent, an antioxidant, a hindered amine light stabilizer, and ultraviolet absorption. Agent.

The curable resin composition (C) of the present invention can be adjusted to a viscosity suitable for coating by coating a coating which is diluted with a solvent as needed.

The amount of the solvent used is usually 2,000% based on the total weight of the curable resin composition. Hereinafter, it is preferably 10 to 500%. Further, the viscosity of the coating material is usually 5 to 5,000 mPa ‧ in terms of the temperature at the time of use (usually 5 to 60 ° C), and is preferably 50 to 1,000 mPa ‧ in terms of stable coating.

The solvent is not particularly limited as long as it dissolves the resin component in the curable resin composition of the present invention. Specific examples thereof include aromatic hydrocarbons (for example, toluene, xylene, and ethylbenzene); esters or ether esters (for example, ethyl acetate, butyl acetate, and methoxybutyl acetate); and ethers (for example, diethyl ether, Tetrahydrofuran, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, monomethyl ether of propylene glycol and monoethyl ether of diethylene glycol; ketone (eg acetone, methyl ethyl ketone, methyl isobutyl ketone, di-) N-butyl ketone and cyclohexanone); alcohol (such as methanol, ethanol, normal or isopropanol, n-, iso-, second or third butanol, 2-ethylhexyl alcohol and benzyl alcohol); For example, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.; anthraquinone (for example, dimethyl hydrazine); water; and a mixed solvent of two or more of these.

Among these solvents, from the viewpoints of smoothness of the coating film and efficiency of solvent removal, esters, ketones and alcohols having a boiling point of 70 to 100 ° C are preferred, and ethyl acetate and methyl ethyl groups are further preferred. Ketone, isopropanol and mixtures of these.

The curable resin composition (C) of the present invention may be applied to at least a part of at least one side of the substrate by dilution with a solvent, and if necessary, dried, and then subjected to active energy rays (ultraviolet rays, electron beams, X). The irradiation or heat of the radiation or the like is hardened, whereby a hard coat coating having a cured film is obtained.

At the time of coating, for example, a coater [bar coater, gravure coater, roll coater (size press roll coater, gate roll coater, etc.), Pneumatic blade coater, spin coater, knife coater, etc.].

The coating film thickness is usually 0.5 to 300 μm as the film thickness after hardening and drying. From the viewpoint of drying property and hardenability, the upper limit is preferably 250 μm, and the lower limit is preferably 1 μm from the viewpoint of abrasion resistance, solvent resistance, and stain resistance.

Examples of the transparent substrate include those composed of a resin such as methyl methacrylate (co)polymer, polyethylene terephthalate, polycarbonate, polytrimethylene cellulose, and polycycloolefin.

When the curable resin composition (C) of the present invention is used by being diluted by a solvent, it is preferred to dry it after application. Examples of the drying method include hot air drying (such as a dryer).

The drying temperature is usually 10 to 200 ° C. The upper limit is preferably 150 ° C from the viewpoint of smoothness and appearance of the coating film, and the lower limit is preferably 30 ° C from the viewpoint of drying speed.

When the curable resin composition (C) of the present invention is cured by ultraviolet rays, various ultraviolet irradiation devices (for example, an ultraviolet irradiation device [Model "VPS/I600", manufactured by Fusion Ultraviolet Systems Co., Ltd.] can be used.

Examples of the lamp to be used include a high pressure mercury lamp and a metal halide lamp. The ultraviolet irradiation amount is preferably from 10 to 10,000 mJ/cm ² , and more preferably from 100 to 5,000 mJ/cm ^{2 from} the viewpoint of the curability of the curable resin composition and the flexibility of the cured product.

The method for producing a curable resin composition (C) of the present invention is a method for producing a curable resin composition (C) comprising an inorganic oxide (A) and a polyfunctional (meth) acrylate (B), characterized in that The method comprises the steps of: selecting, in the polyfunctional (meth) acrylate (B), the inorganic alkoxide (a1), the metal mineral acid salt (a2) and the inorganic chlorine in the presence of the catalyst (b) One or more inorganic oxide precursors (a) in the group of the compounds (a3) are reacted with water to obtain an inorganic oxide (A).

Such a production method can be preferably used as a method for producing the curable resin composition (C) of the present invention.

The step of obtaining the inorganic oxide (A) and its preferred aspect are the same as those in the production of the above inorganic oxide (A). For example, the inorganic oxide precursor (a)/water molar is preferably from 2 to 200, more preferably from 5 to 150, still more preferably from 10 to 100. The catalyst (b), the inorganic alkoxide (a1) used as the inorganic oxide precursor (a), the metal mineral acid salt (a2), and the inorganic chloride (a3) are also the same as described above.

The inorganic oxide (A) and the polyfunctional (meth) acrylate (B) are the same as those in the above curable resin composition (C). The polyfunctional (meth) acrylate (B) preferably contains a polyfunctional (meth) acrylate having a reactive group (α) reactive with a hydroxyl group, and further preferably has reactivity with a hydroxyl group. A polyfunctional (meth) acrylate of the group (α).

If it is carried out in a polyfunctional (meth) acrylate having a reactive group (α), in the presence of a catalyst (b), it is selected from the group consisting of inorganic alkoxides (a1) and metal mineral acid salts (a2). And a step of obtaining an inorganic oxide (A) by reacting one or more inorganic oxide precursors (a) of the inorganic chloride (a3) group with water to obtain a polyfunctional (meth)acrylic acid At least a part of the reactive group (α) in the ester (B) and the inorganic oxide (A), the polyfunctional (meth) acrylate (B) reacts with at least a part of the hydroxyl group in the inorganic oxide (A) to form a chemical bond A hardened resin composition of the knot. After the reaction, the catalyst (b) may be removed from the composition containing the inorganic oxide (A) and the polyfunctional (meth) acrylate (B), or may not be removed, or the catalyst (b) may be neutralized.

In the present invention, the composition containing the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) obtained in the above step of obtaining the inorganic oxide (A) can be used as the curable resin of the present invention. Composition (C). Further, for example, in order to adjust the composition in the curable resin composition The content of the inorganic oxide (A) can be added to the composition containing the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) obtained in the above step of obtaining the inorganic oxide (A). Dilution with a polyfunctional (meth) acrylate (B) of the same kind as the polyfunctional (meth) acrylate (B) used for the production of the inorganic oxide (A) or a different type (B) to obtain hardening Resin composition (C).

[Examples]

Hereinafter, the present invention will be further described by way of Examples and Comparative Examples, but the present invention is not limited thereto. Hereinafter, unless otherwise specified, % means % by weight, and parts means parts by weight.

Manufacturing example 1

In a reaction vessel equipped with a stirrer, a cooling tube, a blowing tube, and a thermometer, dipentaerythritol hexaacrylate (B-1) [trade name: Neoma DA-600, manufactured by Sanyo Chemical Industry Co., Ltd.], 65 parts, water 1.51 parts and tetraethoxy decane (a-1) [trade name: TEOS, manufactured by Tokyo Chemical Industry Co., Ltd.] 35 parts and stirred for 30 minutes, then added p-toluenesulfonic acid (b-1) 2.36 parts, at 65 The reaction was allowed to proceed for 2 hours at °C. Thereafter, the reaction vessel was reduced in pressure and directly distilled at 70 ° C for 2 hours while blowing air to obtain an inorganic oxide (A-1) (tetraethoxy decane reactant (A-1)) A solution of pentaerythritol hexaacrylate (B-1).

Manufacturing example 2~6

The inorganic alkoxide (a), the catalyst (b) and water shown in Table 1 were each carried out in the polyfunctional (meth) acrylate (B) in the same manner as in Production Example 1 in parts per part. The reaction is carried out to obtain a solution of the corresponding (meth) acrylate of the inorganic oxides (A-2) to (A-6).

Comparative manufacturing example 1

The reaction was carried out in the same manner as in Production Example 1 in the parts shown in Table 1, to obtain a solution of the corresponding (meth) acrylate of the inorganic oxide (A'-1). In terms of the use of the monofunctional (meth) acrylate (B'-1), it was used for the inorganic oxide solution of Comparative Example 1.

Comparative manufacturing example 2

The reaction was carried out in the same manner as in Production Example 1 in the parts shown in Table 1, to obtain a solution of the corresponding (meth) acrylate of the inorganic oxide (A'-2). In terms of the content of the inorganic oxide, it was used for the inorganic oxide solution of Comparative Example 2.

Further, the materials used in Table 1 are as follows.

(a1-1): tetraethoxy decane [trade name "TEOS", manufactured by Tokyo Chemical Industry Co., Ltd.]

(a1-2): Tetra-n-butoxytitanium [trade name "B-1", manufactured by Japan Soda Co., Ltd.]

(b-1): p-toluenesulfonic acid [manufactured by Tokyo Chemical Industry Co., Ltd.]

(B-1): Neoma DA-600 [manufactured by Sanyo Chemical Industry Co., Ltd., the main component is dipentaerythritol hexaacrylate (0 hydroxyl groups), but also contains dipentaerythritol pentaacrylate (1 Hydroxyl), dipentaerythritol tetraacrylate (2 hydroxyl groups)

(B-2): ETERMER 235 [Manufactured by Changxing Chemical Co., Ltd., the main component is neopentyl alcohol triacrylate (1 hydroxyl group), but also contains pentaerythritol tetraacrylate (0 hydroxyl groups), new Pentaerythritol diacrylate (2 hydroxyl groups)

(B-3): Neoma EA-300 [manufactured by Sanyo Chemical Industry Co., Ltd., although the main component is neopentyl alcohol tetraacrylate (0 hydroxyl groups), but also contains pentaerythritol triacrylate (1 Hydroxy)]

(B-4): Neoma TA-401 [manufactured by Sanyo Chemical Industry Co., Ltd., the main component is trimethylolpropane EO3 molar addition triacrylate (0 hydroxyl), but also contains trimethylol Propane EO3 molar addition diacrylate (1 hydroxyl)]

(B-5): New Frontier MF-001 [Made by First Industrial Pharmaceutical Co., Ltd., the main component is dipentaerythritol EO adduct hexaacrylate (0 hydroxyl), but also contains dipentaerythritol Alcohol EO adduct pentaacrylate (1 hydroxyl group)

(B'-1): phenoxyethyl acrylate [trade name: Light acrylate PO-A, manufactured by Kyoeisha Chemical Co., Ltd.]

Example 1

103.87 parts of the solution obtained in Production Example 1 and 2-methyl-1-[4-(methylthio)phenyl]-2-N- were added to a reaction vessel equipped with a stirrer, a cooling tube and a thermometer. 3 parts of morphyl propan-1-one (D-2) [trade name "Irgacure 907", manufactured by BASF Corporation] were mixed and stirred at 65 ° C until uniform, and a curable resin composition (C-1) was obtained.

Examples 2 to 6 and Comparative Examples 1 to 2

In the same manner as in Example 1, the respective solutions obtained in Production Examples 2 to 6 and Comparative Production Examples 1 and 2 and the photopolymerization initiator (D) were uniformly mixed in the parts shown in Table 2 to obtain a corresponding The curable resin compositions (C-2) to (C-6) and (C'-1) to (C'-2). The solutions obtained in Production Examples 1 to 6 and Comparative Production Examples 1 and 2 contained the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) shown in Table 2 (or monofunctional (A). Base) acrylate (B')).

Comparative example 3~4

In Comparative Examples 3 and 4, in the parts shown in Table 2, in the polyfunctional (meth) acrylate (B) In the above, the commercially available inorganic oxide fine particles (A'-3) and the photopolymerization initiator (D) are blended at 30% by weight and 10% by weight, respectively, to obtain a curable resin composition (C). '-3) to (C'-4), instead of synthesizing the inorganic oxide (A) in the polyfunctional (meth) acrylate (B) as in the above production example.

Further, the materials used in Table 2 are as follows.

(A'-3): cerium oxide microparticles [trade name "citric acid gel MEK-ST" particle size 10-15nm methyl ethyl ketone (MEK) 40% solution, manufactured by Nissan Chemical Industry Co., Ltd.]

(D-1): 1,3,5-trimethylbenzimidyldiphenylphosphine oxide [trade name "Lucirin TPO", manufactured by BASF Corporation]

(D-2): 2-methyl-1-[4-(methylthio)phenyl]-2-N- Lolinylpropan-1-one [trade name "Irgacure 907", manufactured by BASF Corporation]

(D-3): 1-hydroxycyclohexyl phenyl ketone [trade name "Irgacure 184", manufactured by BASF Corporation]

The properties of the curable resin composition and the film obtained by hardening were evaluated by the following methods. The evaluation results are shown in Table 2. The content of the inorganic oxide (A) in Table 2 is the content (% by weight) of the inorganic oxide (A) in the curable resin composition. Further, a (meth) acrylate solution of an inorganic oxide prepared by using the curable resin compositions (C-1) to (C-6) and (C'-1) to (C'-2), In addition to the inorganic oxide (A) and the polyfunctional (meth) acrylate (B) (or monofunctional (meth) acrylate (B')) shown in Table 2, the production examples shown in Table 1 were also contained. And compare the water and catalyst used in the production example (b). Therefore, the curable resin compositions (C-1) to (C-6) and (C'-1) to (C'-2) also contain the weights shown in Table 1 in addition to the components shown in Table 2. Water and catalyst (b) shown in Table 1.

The tetraethoxy decane reactants (A-1) to (A-2) in Table 2, the tetra-n-butoxy titanium reactant (A-3), and the tetraethoxy decane reactant (A-4) ~(A-6) are the inorganic oxides (A-1) to (A-6) produced in Production Examples 1 to 6, respectively. The tetraethoxy decane reactants (A'-1) to (A'-2) are the inorganic oxides produced in Comparative Production Examples 1 and 2, respectively. (A'-1)~(A'-2).

[Measurement of total light transmittance (transparency of curable resin composition)]

Place a 2cm square and 100μm thick enamel rubber on a glass slide with a thickness of 1mm, and let the curable resin composition flow into the excavated part and sandwich it with another piece of slide glass. For fixing, the total light transmittance (%) was measured in accordance with JIS-K7105 using a total light transmittance measuring device [trade name "haze-gard dual", manufactured by BYK Gardner Co., Ltd.].

Further, the total light transmittance of the curable resin composition of the present invention must be 90% or more.

<hardened film production method>

Non-volatile components were prepared by diluting the curable resin compositions (C-1) to (C-6) and (C'-1) to (C'-4) with methyl ether ketone, respectively. %.

The dilute solution of the curable resin composition was applied to one side of a TAC film (triethylenesulfonated cellulose film) substrate having a thickness of 40 μm by a bar coater so that the film thickness after drying and hardening was 7 μm. After drying at 70 ° C for 1 minute, it was manufactured by Ultraviolet Radiation Systems Co., Ltd. by an ultraviolet irradiation device [Model "VPS/I600". In the same manner as described below, a film having a cured film on the surface of the base film was produced by irradiating ultraviolet rays at 300 mJ/cm ² in a nitrogen atmosphere.

[Evaluation of pencil hardness]

The pencil hardness was measured in accordance with JIS K-5400 for the film having the cured film obtained by the above operation.

In the evaluation conditions, it is preferably 3H or more.

[Evaluation of haze (transparency of film)]

A film having a cured film obtained by the above operation is made in accordance with JIS-K7105 The haze value was measured by a total light transmittance measuring device [trade name "haze-gard dual", manufactured by BYK Gardner Co., Ltd.].

According to the results of Table 2, the curable resin composition of Examples 1 to 6 of the present invention does not impair the transparency of the composition even if a large amount of fine particles of the inorganic oxide are contained, and the cured product has high hardness.

On the other hand, the pencil hardness of Comparative Example 1 using only the monofunctional acrylate was poor. The pencil hardness of Comparative Example 2 in which the content of the inorganic oxide (A) was less than 25% by weight was also insufficient. "Comparative Example 3 obtained by a method of simultaneously adding a commercially available cerium oxide microparticles to a polyfunctional (meth) acrylate (B), containing 30% by weight of cerium oxide microparticles but not satisfying the relationship (1)" , poor transparency. Therefore, in Comparative Example 4 in which the cerium oxide fine particles were reduced to an amount (10% by weight) capable of ensuring transparency, the pencil hardness was insufficient.

[Industrial availability]

A hard coat film having a hard coat film obtained by curing the curable composition of the present invention is excellent in pencil hardness and transparency, and is particularly suitable for plastic optical parts such as flat panel displays and touch panels, and has surface hardness and transparency. The field of excellence.

Claims (13)

A curable resin composition (C) comprising an inorganic oxide (A) and a polyfunctional (meth) acrylate (B), the content of the inorganic oxide (A) being 25 to 80% by weight, and a curable resin composition The total light transmittance of the object is 90% or more, and the following relationship (1) is satisfied; T≧91-1.25×W/100 (1) [wherein W represents an inorganic oxide in the curable resin composition (A) Content (% by weight), and T represents the total light transmittance (%) of the curable resin composition]. The curable resin composition (C) according to the first aspect of the invention, wherein the polyfunctional (meth) acrylate (B) contains a polyfunctional (methyl group) having a reactive group (α) reactive with a hydroxyl group. An acrylate having an aromatic oxide (A) having a hydroxyl group, at least a part of a reactive group (α) in the polyfunctional (meth) acrylate (B) reacting with at least a part of a hydroxyl group in the inorganic oxide (A) Chemical bonding. The curable resin composition (C) according to claim 2, wherein the reactive group (α) is a hydroxyl group or a carboxyl group. The curable resin composition (C) according to any one of claims 1 to 3, wherein the inorganic oxide (A) is selected from the group consisting of inorganic alkoxides (a1) and metal mineral acid salts (a2). A hydrolysis condensate of one or more inorganic oxide precursors (a) in the group consisting of inorganic chlorides (a3). The curable resin composition (C) according to claim 4, wherein the inorganic alkoxide (a1) is selected from the group consisting of a decane oxide, a zirconium alkoxide, a titanium alkoxide, a decane oxide, and a cerane One or more of the group consisting of an oxide, an aluminoxane, a gallium alkoxide, an indium alkoxide, a decane oxide, and a tin alkoxide. The curable resin composition (C) according to claim 4 or 5, wherein the metal mineral acid salt (a2) is selected from the group consisting of titanium tetranitrate, titanyl sulfate, zirconyl nitrate and zirconium sulfate. More than one type. The curable resin composition (C) according to any one of claims 4 to 6, wherein the inorganic chloride (a3) is a chloride of cerium, titanium or zirconium. The curable resin composition (C) according to any one of claims 1 to 7, wherein the cured product has a haze value of 1% or less. The curable resin composition (C) according to any one of claims 1 to 8, wherein the inorganic oxide (A) has a median particle diameter d of 1 as measured by a dynamic light scattering method. ~100nm. The curable resin composition (C) according to any one of claims 1 to 9, which further contains a photopolymerization initiator (D). A method for producing a curable resin composition (C), which is a method for producing a curable resin composition (C) comprising an inorganic oxide (A) and a polyfunctional (meth) acrylate (B), characterized in that The method comprises the steps of: selecting, in the polyfunctional (meth) acrylate (B), the inorganic alkoxide (a1), the metal mineral acid salt (a2) and the inorganic chlorine in the presence of the catalyst (b) One or more inorganic oxide precursors (a) in the group of the compounds (a3) are reacted with water to obtain an inorganic oxide (A). The method for producing a curable resin composition (C) according to claim 11, wherein the polyfunctional (meth) acrylate (B) contains a polyfunctional group having a reactive group (α) reactive with a hydroxyl group. (Meth) acrylate. A method for producing a curable resin composition (C) according to claim 11 or 12, Among them, the inorganic oxide precursor (a) / water molar ratio is 2 to 200.