JP4774722B2 - Liquid curable resin composition and cured film comprising the same - Google Patents

Description

  The present invention relates to a liquid curable resin composition and a cured film comprising the same, and in particular, for example, from one coating film obtained by applying the present composition, two layers, such as a low refractive index layer and a high refractive index layer. The present invention relates to a liquid curable resin composition capable of forming a cured film having the above layer structure, a cured film comprising the same, and a laminate including a cured film having an arbitrary multilayer structure.

  Currently, with the development of multimedia, various developments have been seen in various display devices (display devices). Among various types of display devices, especially those used outdoors, mainly for portable use, the improvement in visibility has become increasingly important, and even in large display devices, it is easier to see. This is a technical issue as it is required by consumers.

  Conventionally, as one means for improving the visibility of a display device, an antireflection film made of a low refractive index material is coated on a substrate of the display device, and a method of forming the antireflection film For example, a method of forming a fluorine compound thin film by a vapor deposition method is known. However, in recent years, there has been a demand for a technique capable of forming an antireflection film for a large display device at a low cost centering on a liquid crystal display device. However, in the case of the vapor deposition method, it is difficult to form a high-efficiency and uniform antireflection film on a large-area substrate, and a vacuum apparatus is required, so that the cost can be reduced. Have difficulty.

  Under such circumstances, a method of forming an antireflection film by preparing a liquid composition by dissolving a fluorine-based polymer having a low refractive index in an organic solvent and applying it to the surface of a substrate has been studied. Yes. For example, it has been proposed to apply a fluorinated alkylsilane to the surface of a substrate (see, for example, Patent Document 1 and Patent Document 2). In addition, a method of applying a fluorine-based polymer having a specific structure has been proposed (see, for example, Patent Document 3).

JP 61-40845 A Japanese Examined Patent Publication No. 6-98703 Japanese Patent Application Laid-Open No. 6-1115023

These conventional anti-reflective coatings made of fluorine-based materials require the formation of a low-refractive-index layer made of a fluorine-based material on the high-refractive index layer provided on the substrate. It was necessary to provide the process separately.
Further, the scratch resistance of the low refractive index layer as the surface layer was not sufficient.
The present invention has been made against the background of the above situation, and the object thereof is to efficiently manufacture any two or more consecutive layers such as a low refractive index layer and a high refractive index layer. The object is to provide a liquid curable resin composition. Another object of the present invention is to provide a cured film having high transparency, high adhesion to a substrate, and excellent scratch resistance and dust wiping properties.

  In order to achieve the above object, the present inventors have earnestly clarified the liquid curable resin composition that gives a cured film having a layer structure of two or more layers from one coating film, and the mechanism of separation into two or more layers. After repeated research, the fluorine-containing polymer having a specific structure and the specific metal oxide particles were dissolved in the fluorine-containing polymer having a hydroxyl group in the molecule, the dispersion stability to the metal oxide particles, and the relative evaporation rate. By selecting and combining one or more of the solvent types divided into two types, one coating film obtained by applying this liquid curable resin composition is separated into a plurality of layers, and the solvent By selecting the type and other conditions, it was found that any type of metal oxide particles can be separated into a plurality of layers, and the present invention has been completed.

That is, the present invention provides the following liquid curable resin composition, a cured film comprising the same, and a method for producing the cured film.
[1] The following components (A) to (F):
(A) Fluoropolymer having a hydroxyl group in the molecule (B) One or two or more metal oxide particles (hereinafter referred to as “a”) having a number average particle diameter of 100 nm or less and a refractive index of 1.50 or more. (B) Metal oxide particles ”
(C) (A) One or two or more solvents (hereinafter referred to as “(C) fast volatile solvent”) having high solubility in a fluorine-containing polymer having a hydroxyl group in the molecule
(D) (B) one or two or more solvents (hereinafter referred to as “(D) slow volatile solvent”) having high dispersion stability with respect to the metal oxide particles and being compatible with (C) the fast volatile solvent. Called)
(E) Curable compound (F) Liquid curing comprising a thermal acid generator and (C) the relative evaporation rate of the fast volatile solvent is higher than (D) the relative evaporation rate of the slow volatile solvent Resin composition.
[2] The (C) fast volatile solvent is one or more solvents having low dispersion stability with respect to (B) metal oxide particles, and (D) the slow volatile solvent is (A) in the molecule. The liquid curable resin composition as described in [1] above, which is one or more solvents having low solubility in a fluoropolymer having a hydroxyl group.
[3] (B) The metal oxide particles are made of titanium oxide, zirconium oxide, antimony-containing tin oxide, tin-containing indium oxide, aluminum oxide, cerium oxide, zinc oxide, tin oxide, antimony-containing zinc oxide, and indium-containing zinc oxide. The liquid curable resin composition according to the above [1] or [2], wherein the liquid curable resin composition is a particle mainly composed of one or more selected metal oxides.
[4] The liquid curable resin composition according to the above [3], wherein the metal oxide particles (B) are particles mainly composed of titanium oxide.
[5] The liquid curable resin composition according to any one of [1] to [4] above, wherein the (B) metal oxide particles are metal oxide particles having a multilayer structure.
[6] A cured film obtained by curing the liquid curable resin composition according to any one of [1] to [5], and having a multilayer structure of two or more layers.
[7] Each layer constituting the multilayer structure is (B) a layer in which metal oxide particles are present at a high density or (B) a layer in which metal oxide particles are not substantially present, and at least one layer is ( B) The cured film as described in [6] above, wherein the metal oxide particles are a layer having a high density.
[8] Production of a cured film comprising a step of curing the liquid curable resin composition according to any one of the above [1] to [5] by heating or irradiation with radiation. Method.

Since the liquid curable resin composition of the present invention can form a cured film having a multilayer structure such as a high refractive index layer and a low refractive index layer from one coating film, the manufacturing process of the cured film can be simplified. .
Further, by making the metal oxide particles unevenly distributed, the scratch resistance of the cured film can be improved.

  Therefore, the liquid curable resin composition of the present invention can be advantageously used for the formation of optical materials such as an antireflection film and a selective transmission film filter, and also has a high weather resistance by utilizing its high fluorine content. It can be suitably used as a coating material, a weather-resistant film material, a coating material, and the like for a substrate that requires properties. In addition, the cured film has excellent adhesion to the base material, high scratch resistance, and imparts a good antireflection effect. Therefore, the cured film is extremely useful as an antireflection film, and can be applied to various display devices. The visibility can be improved.

Hereinafter, the present invention will be described in detail by dividing it into a liquid curable resin composition, a cured film and a laminate.
1. Liquid curable resin composition The liquid curable resin composition of this invention contains the following component (A)-(F).
(A) Fluoropolymer having a hydroxyl group in the molecule (B) One or two or more metal oxide particles (hereinafter referred to as “a”) having a number average particle diameter of 100 nm or less and a refractive index of 1.50 or more. (B) Metal oxide particles ”
(C) (A) One or two or more solvents (hereinafter referred to as “(C) fast volatile solvent”) having high solubility in a fluorine-containing polymer having a hydroxyl group in the molecule
(D) (B) one or two or more solvents (hereinafter referred to as “(D) slow volatile solvent”) having high dispersion stability with respect to the metal oxide particles and being compatible with (C) the fast volatile solvent. Called)
(E) Curable compound (F) Thermal acid generator Hereinafter, these components will be described individually.

(A) Fluorinated polymer having a hydroxyl group in the molecule The fluorinated polymer is a polymer having a carbon-fluorine bond in the molecule, and the fluorine content is preferably 30% by mass or more. It is preferable that the number average molecular weight by polystyrene conversion obtained by permeation chromatography is 5000 or more. Here, the fluorine content is a value measured by the alizarin complexone method, and the number average molecular weight is a value when tetrahydrofuran is used as a developing solvent.

  An example of the fluoropolymer used in the present invention is a fluoropolymer having a hydroxyl group in the molecule (hereinafter referred to as “hydroxyl group-containing fluoropolymer”). Preferable examples of the hydroxyl group-containing fluoropolymer include those having a polysiloxane segment in the main chain, which contains 10 mol% to 50 mol% of a structural unit derived from a monomer containing a hydroxyl group. The hydroxyl group-containing fluoropolymer is an olefin polymer having a polysiloxane segment represented by the following general formula (1) in the main chain, and the ratio of the polysiloxane segment in the fluoropolymer is usually 0. It is preferable that it is 1-20 mol%.

In the formula, R ¹ and R ² may be the same or different and each represents a hydrogen atom, an alkyl group, a halogenated alkyl group or an aryl group.

  Further, the hydroxyl group-containing fluoropolymer preferably has a fluorine content of 30% by mass or more, more preferably 40-60% by mass, and the number average molecular weight in terms of polystyrene obtained by gel permeation chromatography, Preferably it is 5000 or more, More preferably, it is 10000-500000.

  The hydroxyl group-containing fluoropolymer includes (a) a fluorine-containing olefin compound (hereinafter referred to as “component (a)”), (b) a monomer compound containing a hydroxyl group copolymerizable with the component (a) (hereinafter referred to as “component (a)”). (Referred to as “component (b)”) and (c) an azo group-containing polysiloxane compound (hereinafter referred to as “component (c)”) and, if necessary, (d) a reactive emulsifier (hereinafter referred to as “(d ) Component)) and / or (e) It can be obtained by reacting a monomer compound other than the component (b) copolymerizable with the component (a).

  Examples of the fluorine-containing olefin compound as component (a) include compounds having at least one polymerizable unsaturated double bond and at least one fluorine atom. Specific examples thereof include, for example, (1) fluoroolefins such as tetrafluoroethylene, hexafluoropropylene, 3,3,3-trifluoropropylene; (2) perfluoro (alkyl vinyl ether) or perfluoro (alkoxyalkyl vinyl ether); (3) perfluoro (methyl) (4) Perfluoro (propoxypropyl vinyl) Ether) such as perfluoro (alkoxyalkyl vinyl ethers); other can be exemplified. These compounds can be used alone or in combination of two or more. Among these, hexafluoropropylene, perfluoro (alkyl vinyl ether) or perfluoro (alkoxyalkyl vinyl ether) is particularly preferable, and a combination thereof is preferably used.

  Examples of the monomer compound containing a hydroxyl group as component (b) include (1) 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl. Hydroxyl group-containing vinyl ethers such as vinyl ether, 5-hydroxypentyl vinyl ether and 6-hydroxyhexyl vinyl ether; (2) hydroxyl group-containing allyl ethers such as 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether and glycerol monoallyl ether; 3) allyl alcohol; (4) hydroxyethyl (meth) acrylate; These compounds can be used alone or in combination of two or more. Preferred are hydroxyl-containing alkyl vinyl ethers.

  As the azo group-containing polysiloxane compound of component (c), a compound having a polysiloxane segment represented by the above general formula (1) while containing an azo group which is easily thermally cleaved represented by -N = N- For example, it can be manufactured by the method described in JP-A-6-93100. Specific examples of the component (c) include compounds represented by the following general formula (2).

In the formula, y = 10 to 500 and z = 1 to 50.

  Preferred combinations of the components (a), (b) and (c) are, for example, (1) fluoroolefin / hydroxyl group-containing alkyl vinyl ether / polydimethylsiloxane unit, (2) fluoroolefin / perfluoro (alkyl vinyl ether) / Hydroxyl group-containing alkyl vinyl ether / polydimethylsiloxane unit, (3) fluoroolefin / perfluoro (alkoxyalkyl vinyl ether) / hydroxyl group-containing alkyl vinyl ether / polydimethylsiloxane unit, (4) fluoroolefin / perfluoro (alkyl vinyl ether) / hydroxyl group-containing alkyl vinyl ether / Polydimethylsiloxane unit, (5) fluoroolefin / perfluoro (alkoxyalkyl vinyl ether) / hydroxyl group-containing alkyl vinyl ether / polydimethylsiloxane It is a down unit.

  In the hydroxyl group-containing fluoropolymer, the structural unit derived from the component (a) is preferably 20 to 70 mol%, more preferably 25 to 65 mol%, and particularly preferably 30 to 60 mol%. When the proportion of the structural unit derived from the component (a) is less than 20 mol%, the fluorine content in the obtained fluoropolymer tends to be excessive, and the cured product of the resulting liquid curable resin composition has a sufficient refractive index. It is hard to be low. On the other hand, when the proportion of the structural unit derived from the component (a) exceeds 70 mol%, the solubility of the obtained fluoropolymer in an organic solvent is remarkably lowered, and the obtained liquid curable resin composition is: The transparency and adhesion to the substrate are small.

  In the hydroxyl group-containing fluoropolymer, the structural unit derived from the component (b) is preferably 10 to 50 mol%. More preferably, the lower limit is 13 mol% or more, more preferably more than 20 mol% and 21 mol% or more, and preferably the upper limit is 45 mol% or less, more preferably 35 mol% or less. It is. By constituting a liquid curable resin composition using such a fluorine-containing polymer containing a predetermined amount of component (b), it is possible to achieve good scratch resistance and dust wiping in the cured product. it can. On the other hand, when the proportion of the structural unit derived from the component (b) is less than 10 mol%, the fluoropolymer has poor solubility in an organic solvent, and when it exceeds 50 mol%, the liquid curable resin composition The cured product of the product has deteriorated optical properties such as transparency and low reflectance.

  The component (c) azo group-containing polysiloxane compound itself is a thermal radical generator, and has a function as a polymerization initiator in a polymerization reaction for obtaining a fluorinated polymer. It can also be used together. The proportion of the structural unit derived from the component (c) in the fluoropolymer is preferably 0.1 to 20 mol%, more preferably 0.1 to 15 in the polysiloxane segment represented by the general formula (1). The proportion is such that it is mol%, particularly preferably 0.1 to 10 mol%, particularly preferably 0.1 to 5 mol%. When the proportion of the polysiloxane segment represented by the general formula (1) exceeds 20 mol%, the resulting hydroxyl group-containing fluoropolymer is inferior in transparency, and when used as a coating agent. , Repelling and the like are likely to occur during application.

  In addition to the components (a) to (c), a reactive emulsifier is preferably used as the monomer component as the component (d). By using this (d) component, when using a hydroxyl-containing fluoropolymer as a coating agent, favorable coating property and leveling property can be obtained. As the reactive emulsifier, it is particularly preferable to use a nonionic reactive emulsifier. Specific examples of the nonionic reactive emulsifier include compounds represented by the following general formula (3) or general formula (4).

In the formula, n = 1 to 20, m and s represent repeating units, and m = 0 to 4 and s = 3 to 50.

In the formula, m and s are the same as those in the general formula (3). R ³ is an alkyl group which may be linear or branched, and is preferably an alkyl group having 1 to 40 carbon atoms.

  In the hydroxyl group-containing fluoropolymer, the proportion of the structural unit derived from the component (d) is preferably 0 to 10 mol%, more preferably 0.1 to 5 mol%, particularly preferably 0.1 to 1 mol. %. When this ratio exceeds 10 mol%, the liquid curable resin composition obtained becomes sticky, so that handling becomes difficult, and moisture resistance decreases when used as a coating agent.

  (E) As a monomer compound other than the component (b) that can be copolymerized with the component (a), (1) methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, Alkyl vinyl ethers or cycloalkyl vinyl ethers such as isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether; (2) vinyl acetate , Vinyl carboxylates such as vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl caproate, vinyl versatate, vinyl stearate; ) Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (n- (Meth) acrylic acid esters such as propoxy) ethyl (meth) acrylate; (4) carboxyl group-containing monomer compounds such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, etc. The thing which does not contain a hydroxyl group can be mentioned. Alkyl vinyl ether is preferable.

  In the hydroxyl group-containing fluoropolymer, the proportion of the structural unit derived from the component (e) is preferably 0 to 70 mol%, more preferably 5 to 35 mol%. When this ratio exceeds 70 mol%, the resulting liquid curable resin composition becomes tacky and difficult to handle, and moisture resistance decreases when used as a coating agent.

When the component (d) is contained, preferred combinations of the component (a), the component (b), the component (c), the component (d), and the component (e) are as follows.
(1) fluoroolefin / hydroxyl group-containing vinyl ether / polydimethylsiloxane unit / nonionic reactive emulsifier / alkyl vinyl ether, (2) fluoroolefin / perfluoro (alkyl vinyl ether) / hydroxyl group-containing vinyl ether / polydimethylsiloxane unit / nonionic reactive emulsifier / Alkyl vinyl ether, (3) fluoroolefin / perfluoro (alkoxyalkyl vinyl ether) / hydroxyl group-containing vinyl ether / polydimethylsiloxane unit / nonionic reactive emulsifier / alkyl vinyl ether, (4) fluoroolefin / perfluoro (alkyl vinyl ether) / hydroxyl group-containing vinyl ether / Polydimethylsiloxane unit / nonionic reactive emulsifier / alkyl vinyl ether, (5) fluoroolefin / perfluoro (A) Job Shi alkyl vinyl ether) / hydroxyl group-containing vinyl ether / polydimethylsiloxane unit / nonionic reactive emulsifier / alkyl vinyl ether.

  Examples of radical polymerization initiators that can be used in combination with component (c) include (1) diacyl peroxides such as acetyl peroxide and benzoyl peroxide; (2) ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide. (3) Hydroperoxides such as hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide; (4) Di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc. Dialkyl peroxides; (5) peroxyesters such as tert-butylperoxyacetate and tert-butylperoxypivalate; and (6) azo-based compounds such as azobisisobutyronitrile and azobisisovaleronitrile. Compounds like; (7) ammonium persulfate, sodium persulfate, persulfates such as potassium persulfate; Other can be exemplified.

  Specific examples other than the above radical polymerization initiator include, for example, perfluoroethyl iodide, perfluoropropyl iodide, perfluorobutyl iodide, (perfluorobutyl) ethyl iodide, perfluorohexyl iodide, 2- (Perfluorohexyl) ethyl iodide, perfluoroheptyl iodide, perfluorooctyl iodide, 2- (perfluorooctyl) ethyl iodide, perfluorodecyl iodide, 2- (perfluorodecyl) ethyl iodide, heptafluoro 2-iodopropane, perfluoro-3-methylbutyl iodide, perfluoro-5-methylhexyl iodide, 2- (perfluoro-5-methylhexyl) ethyl iodide, perfluoro-7-methyloctyl iodide 2- (perfluoro-7-methyloctyl) ethyl iodide, perfluoro-9-methyldecyl iodide, 2- (perfluoro-9-methyldecyl) ethyl iodide, 2,2,3,3-tetrafluoropropyl iodide 1H, 1H, 5H-octafluoropentyl iodide, 1H, 1H, 7H-dodecafluoroheptyl iodide, tetrafluoro-1,2-diiodoethane, octafluoro-1,4-diiodobutane, dodecafluoro-1,6-diiodohexane And iodine-containing fluorine compounds. The iodine-containing fluorine compound can be used alone or in combination with the organic peroxide, azo compound or persulfate.

  As a polymerization mode for producing a hydroxyl group-containing fluoropolymer, any of an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method or a solution polymerization method using a radical polymerization initiator can be used. However, an appropriate one can be selected from batch, semi-continuous or continuous operations.

  The polymerization reaction for obtaining the hydroxyl group-containing fluoropolymer is preferably carried out in a solvent system using a solvent. Examples of preferable organic solvents include (1) esters such as ethyl acetate, butyl acetate, isopropyl acetate, isobutyl acetate, and cellosolve; (2) ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; (3) Cyclic ethers such as tetrahydrofuran and dioxane; (4) Amides such as N, N-dimethylformamide and N, N-dimethylacetamide; (5) Aromatic hydrocarbons such as toluene and xylene; be able to. Further, if necessary, alcohols, aliphatic hydrocarbons and the like can be mixed and used.

  The hydroxyl group-containing fluoropolymer obtained as described above may be able to use the reaction solution obtained by the polymerization reaction as it is as a liquid curable resin composition as it is. Appropriate post-processing can also be performed. As this post-treatment, for example, a general method represented by a purification method in which a polymerization reaction solution is added dropwise to an insolubilizing solvent for the hydroxyl group-containing fluoropolymer made of alcohol or the like to coagulate the hydroxyl group-containing fluoropolymer. Reprecipitation treatment can be performed, and then the resulting solid copolymer is dissolved in a solvent to prepare a hydroxyl group-containing fluoropolymer solution. Moreover, what remove | eliminated the residual monomer from the polymerization reaction solution can also be used as a solution of a hydroxyl-containing fluoropolymer as it is.

  The blending ratio of the (A) hydroxyl group-containing fluoropolymer in the solid content of 100% by mass of the liquid curable resin composition of the present invention is usually 5 to 70% by mass, preferably 10 to 50% by mass. Thus, the transparency of the cured film is improved.

(B) Metal oxide particles The (B) metal oxide particles used in the present invention are metal oxide particles having a number average particle diameter of 100 nm or less and a refractive index of 1.50 or more. When the number average particle diameter exceeds 100 nm, it may be difficult to uniformly disperse the metal oxide particles. In addition, the metal oxide particles are liable to settle and lack storage stability. Furthermore, the transparency of the obtained cured film may decrease, or turbidity (Haze value) may increase.
The number average particle diameter is more preferably from 10 to 80 nm, further preferably from 20 to 50 nm.
The “number average particle size” is the number average particle size measured by electron microscopy. When the metal oxide particles are aggregated, it is the primary particle size, and when the metal oxide particles are not spherical ( For example, acicular ATO or the like), the average of the long diameter (longitudinal) and the short diameter (horizontal). Further, when the particle shape is a rod shape (refers to a shape having an aspect ratio of more than 1 and 10 or less), the minor axis is defined as the particle diameter.

  The metal oxide particles preferably include titanium oxide, zirconium oxide (zirconia), antimony-containing tin oxide, tin-containing indium oxide, aluminum oxide (alumina), cerium oxide, zinc oxide, tin oxide, antimony-containing zinc oxide and indium. Particles based on one or more metal oxides selected from zinc oxide can be used.

  Here, metal oxide particles having a multilayer structure in which the metal oxide particles are coated with the one or more metal oxides other than the metal oxide can also be used. Specific examples of the metal oxide particles having a multilayer structure include silica-coated titanium oxide particles, alumina-coated titanium oxide particles, zirconia-coated titanium oxide particles, alumina, and zirconia-coated titanium oxide particles. Among such metal oxide particles, particles mainly composed of titanium oxide or alumina / zirconia-coated titanium oxide particles are particularly preferable.

  By using metal oxide particles having a multilayer structure, the photocatalytic activity of titanium oxide can be suppressed, and decomposition of the cured product can be suppressed. As a result, a cured film having a high refractive index and excellent light resistance can be obtained.

  Moreover, antistatic property can be provided to the cured film by using antimony-containing tin oxide particles (ATO) or the like. In this case, as will be described later, since ATO particles are unevenly distributed, effective antistatic properties and good transparency can be achieved with a smaller amount of added particles.

  As particles mainly composed of titanium oxide, known particles can be used, and the shape thereof may be hollow particles, porous particles, core-shell type particles, and the like. Further, the shape is not limited to a spherical shape, and may be a rod-like shape (referring to a shape having an aspect ratio exceeding 1 and not more than 10) or an irregular shape, and a rod-like shape is preferable. The number average particle diameter determined by electron microscopy is preferably in the range of 1 to 100 nm.

  The dispersion medium is preferably water or an organic solvent. Examples of organic solvents include alcohols such as methanol, isopropyl alcohol, ethylene glycol, butanol and ethylene glycol monopropyl ether; ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as toluene and xylene; dimethylformamide and dimethyl Examples include amides such as acetamide and N-methylpyrrolidone; esters such as ethyl acetate, butyl acetate and γ-butyrolactone; and organic solvents such as ethers such as tetrahydrofuran and 1,4-dioxane. Of these, alcohols and ketones are preferred. These organic solvents can be used alone or in combination of two or more as a dispersion medium.

  As a commercial item of the particle | grains which have a titanium oxide as a main component, the product etc. by Teika Co., Ltd. and CI Kasei Co., Ltd. can be mentioned, for example.

  The blending ratio of the (B) metal oxide particles with respect to 100% by mass of the solid content of the liquid curable resin composition is usually 10 to 90% by mass, preferably 20 to 80% by mass.

(C) Fast volatile solvent The (C) fast volatile solvent contained in the liquid curable resin composition of the present invention is one or more solvents having high solubility in the above (A) hydroxyl group-containing fluoropolymer. is there. Here, the high solubility in the hydroxyl group-containing fluoropolymer means that (A) the hydroxyl group-containing fluoropolymer is added to each solvent so as to be 50% by mass and stirred visually at room temperature for 8 hours. A uniform solution. The relative evaporation rate of the (C) fast volatile solvent needs to be larger than the relative evaporation rate of the later-described (D) slow volatile solvent. Here, “relative evaporation rate” refers to the relative value of evaporation rate based on the time required for 90% by mass of butyl acetate to evaporate. For details, see TECHNIQUES OF CHEMISTRY VOL.2 ORGANIC SOLVENTS Physical Properties.
and methods of purification 4th ed. (Interscience Publishers, Inc. 1986 page
62). The (C) fast volatile solvent preferably has low dispersion stability with respect to the (B) metal oxide particles. (C) The fast volatile solvent has a relative evaporation rate higher than (D), (A) high solubility in a hydroxyl group-containing fluoropolymer, and (B) low dispersion stability in metal oxide particles. Thus, in the process of applying the liquid curable resin composition of the present invention to the substrate and evaporating the solvents (C) and (D), (B) the metal oxide particles can be unevenly distributed.

  The solvent that can be used as the (C) fast volatile solvent in the present invention is a solvent having a relative evaporation rate of about 1.7 or more. Specifically, methyl ethyl ketone (MEK; relative evaporation rate 3.8), isopropanol (IPA; 1.7), methyl isobutyl ketone (MIBK; relative evaporation rate 1.6), methyl amyl ketone (MAK; 0.3), acetone, methyl propyl ketone and the like.

(D) Slow volatile solvent (D) Slow volatile solvent contained in the liquid curable resin composition of the present invention is one or more solvents having high dispersion stability with respect to the metal oxide particles (B). is there. Here, (B) that the dispersion stability with respect to the metal oxide particles is high means that (B) the metal oxide particles are adhered to the glass wall by immersing the glass plate in an isopropanol dispersion of the metal oxide particles. When (B) the glass plate to which the metal oxide particles are adhered is immersed in each solvent, (B) the metal oxide particles are visually dispersed uniformly in the solvent. The (D) slow volatile solvent preferably has low solubility in the above (A) hydroxyl group-containing fluoropolymer.

  The solvent that can be used as the (D) slow volatile solvent in the present invention is a solvent having a relative evaporation rate of about 1.7 or less, specifically, methanol (relative evaporation rate 2.1), isopropanol (IPA). 1.7), n-butanol (n-BuOH; 0.5), tert-butanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, ethyl cellosolve, propyl cellosolve, butyl cellosolve, etc. It is done.

As the (C) fast volatile solvent and / or (D) slow volatile solvent used in the present invention, the solvent used in the production of the (A) hydroxyl group-containing fluoropolymer can be used as it is.
The (C) fast volatile solvent and (D) slow volatile solvent used in the present invention must be compatible. The compatibility is sufficient if the specific composition of the composition of the present invention has such compatibility that (C) the fast volatile solvent and (D) the slow volatile solvent are not separated.
Here, whether the selected solvent corresponds to (C) fast volatile solvent or (D) slow volatile solvent used in the present invention is relatively determined among a plurality of selected solvent types. Therefore, isopropanol having a relative evaporation rate of 1.7 may be used as (C) a fast volatile solvent or (D) a slow volatile solvent.

  Further, in the liquid curable resin composition of the present invention, the solvent is a solvent other than the above (C) fast volatile solvent and (D) slow volatile solvent for the purpose of improving the coating property of the composition and other purposes. Can be blended. Examples of the solvent blended for such purposes include ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, and esters such as ethyl acetate and butyl acetate. Further, in the solution of the liquid curable resin composition of the present invention, a solvent that cannot dissolve the fluoropolymer, for example, a poor solvent such as water, alcohols, ethers, etc. Can be used together. Thereby, the solution of the fluoropolymer may have good storage properties and preferable coating properties. Examples of such a poor solvent include ethyl alcohol, isopropyl alcohol, tert-butyl alcohol, ethyl cellosolve, and butyl cellosolve.

  The total amount of the solvent (C) and the solvent (D) is usually 300 to 5000 with respect to 100 parts by mass of the total amount of the components other than the solvent (including the components (C) and (D)) in the liquid curable resin composition. Part by mass, preferably 300 to 4000 parts by mass, more preferably 300 to 3000 parts by mass is used. The mixing ratio (mass ratio) of the solvent (C) and the solvent (D) may be arbitrary in the range of 1:99 to 99: 1.

(E) Curable compound (E) A curable compound is a component which superposes | polymerizes by heating etc. and provides sclerosis | hardenability to this-application composition.

  Examples of the curable compound include various amino compounds, various hydroxyl-containing compounds such as pentaerythritol, polyphenol, and glycol, and others.

  The amino compound used as the curable compound is an amino group capable of reacting with the hydroxyl group in the hydroxyl group-containing fluoropolymer (A), for example, one or both of a hydroxyalkylamino group and an alkoxyalkylamino group in total. A compound containing two or more, and specific examples include melamine compounds, urea compounds, benzoguanamine compounds, glycoluril compounds, and the like.

  Melamine compounds are generally known as compounds having a skeleton in which a nitrogen atom is bonded to a triazine ring, and specific examples include melamine, alkylated melamine, methylol melamine, alkoxylated methyl melamine, and the like. However, it is preferable to have one or both of a methylol group and an alkoxylated methyl group in one molecule in total. Specifically, methylolated melamine obtained by reacting melamine and formaldehyde under basic conditions, alkoxylated methylmelamine, or a derivative thereof is preferable, and in particular, liquid curable resin compositions have good storage stability. Alkoxylated methyl melamine is preferred in that it is obtained and good reactivity is obtained. There are no particular limitations on the methylolated melamine and the alkoxylated methylmelamine used as the curable compound. For example, it can be obtained by the method described in the document “Plastic Materials Course [8] Urea Melamine Resin” (Nikkan Kogyo Shimbun). Various resinous materials can be used.

  In addition to urea, examples of the urea compound include polymethylolated urea, alkoxylated methylurea which is a derivative thereof, methylolated uron having a uron ring, and alkoxylated methyluron. And also about compounds, such as a urea derivative, the use of the various resinous materials described in said literature is possible.

  The compounding ratio of the curable compound contained in the solid content of 100% by mass of the liquid curable resin composition is usually 3 to 70% by mass, preferably 3 to 50% by mass, more preferably 5 to 30% by mass. is there. If the amount of the curable compound used is too small, the durability of the thin film formed by the resulting liquid curable resin composition may be insufficient, and if it is out of the range of 3 to 70% by mass, fluorine-containing In the reaction with the polymer, it is difficult to avoid gelation, and the cured product may become brittle.

  (A) The reaction between the hydroxyl group-containing fluoropolymer and the (E) curable compound is, for example, adding a curable compound to a solution of an organic solvent in which the hydroxyl group-containing fluoropolymer is dissolved, and heating for an appropriate time. What is necessary is just to carry out, making a reaction system uniform by stirring etc. The heating temperature for this reaction is preferably in the range of 30 to 150 ° C, more preferably in the range of 50 to 120 ° C. If the heating temperature is less than 30 ° C., the reaction proceeds very slowly. If the heating temperature exceeds 150 ° C., in addition to the intended reaction, a cross-linking reaction is caused by a reaction between methylol groups or alkoxylated methyl groups in the curable compound. This is not preferable because a gel is formed. The progress of the reaction is quantitative by measuring the amount of methylol group or alkoxylated methyl group by infrared spectroscopic analysis or by collecting the dissolved polymer by reprecipitation method and measuring the increase. Can be confirmed.

  In addition, it is preferable to use the same organic solvent as that used in the production of the hydroxyl group-containing fluoropolymer for the reaction of (A) the hydroxyl group-containing fluoropolymer and (E) the curable compound. In the present invention, the reaction solution obtained by the hydroxyl group-containing fluoropolymer and the curable compound thus obtained can be used as it is as a solution of the liquid curable resin composition, and various additions can be made as necessary. It can also be used after blending an agent.

(F) Thermal acid generator The thermal acid generator that can be blended in the liquid curable resin composition of the present invention is heated when the coating film of the liquid curable resin composition is heated and cured. It is a substance that can improve the conditions to be milder. Specific examples of the thermal acid generator include, for example, various aliphatic sulfonic acids and salts thereof, various aliphatic carboxylic acids and salts thereof such as citric acid, acetic acid, and maleic acid, and various aromatic acids such as benzoic acid and phthalic acid. Examples thereof include carboxylic acids and salts thereof, alkylbenzene sulfonic acids and ammonium salts thereof, various metal salts, phosphoric acid and organic acid phosphoric esters.
The ratio of the thermal acid generator used in the solid content of 100% by mass of the liquid curable resin composition is usually 0.01 to 10% by mass, preferably 0.1 to 5% by mass. When this ratio is excessive, the storage stability of the liquid curable resin composition is deteriorated, which is not preferable.

(G) Additive In the liquid curable resin composition of the present invention, for the purpose of improving the coating properties of the liquid curable resin composition and the physical properties of the thin film after curing, imparting photosensitivity to the coating film, etc. For example, various polymers and monomers having a hydroxyl group, colorants such as pigments or dyes, various additives such as stabilizers such as anti-aging agents and ultraviolet absorbers, photosensitive acid generators, surfactants, polymerization inhibitors An agent can be included. In particular, it is preferable to add a thermal acid generator or a photoacid generator for the purpose of improving the hardness and durability of the formed cured film, and in particular, the transparency after curing of the liquid curable resin composition is reduced. It is preferable to select and use one that is not dissolved and that dissolves uniformly in the solution.

(1) Polymer having a hydroxyl group As a polymer having a hydroxyl group that can be blended in the liquid curable resin composition of the present invention, for example, a hydroxyl group-containing copolymerizable monomer such as hydroxyethyl (meth) acrylate is copolymerized. Examples of the polymer, the novolak resin, or the resol resin obtained in this manner include resins having a known phenol skeleton.

(2) Colorant such as pigment or dye Examples of the colorant that can be blended in the liquid curable resin composition of the present invention include (1) extender pigments such as white alumina, clay, barium carbonate, and barium sulfate; (2) Inorganic pigments such as zinc white, lead white, yellow lead, red lead, ultramarine, bitumen, titanium oxide, zinc chromate, bengara, carbon black; (3) Brilliant Carmine 6B, Permanent Red 6B, Permanent Red R, Organic pigments such as benzidine yellow, phthalocyanine blue, and phthalocyanine green; (4) basic dyes such as magenta and rhodamine; (5) direct dyes such as direct scarlet and direct orange; Other can be mentioned.

(3) Stabilizers such as anti-aging agents and UV absorbers As anti-aging agents and UV absorbers that can be blended in the liquid curable resin composition of the present invention, known ones can be used.
Specific examples of the antioxidant include, for example, di-tert-butylphenol, pyrogallol, benzoquinone, hydroquinone, methylene blue, tert-butylcatechol, monobenzyl ether, methylhydroquinone, amylquinone, amyloxyhydroquinone, n-butylphenol, phenol, hydroquinone Monopropyl ether, 4,4 '-[1- [4- (1- (4-hydroxyphenyl) -1-methylethyl) phenyl] ethylidene] diphenol, 1,1,3-tris (2,5-dimethyl) -4-hydroxyphenyl) -3-phenylpropane, diphenylamines, phenylenediamines, phenothiazine, mercaptobenzimidazole, and the like.

  Specific examples of ultraviolet absorbers include, for example, salicylic acid ultraviolet absorbers represented by phenyl salicylate, benzophenone ultraviolet absorbers such as dihydroxybenzophenone and 2-hydroxy-4-methoxybenzophenone, and benzotriazole ultraviolet absorbers. Ultraviolet absorbers used as additives for various plastics such as cyanoacrylate-based ultraviolet absorbers can be used.

(4) Photosensitive acid generator The photosensitive acid generator that can be blended in the liquid curable resin composition of the present invention imparts photosensitivity to the coating film of the liquid curable resin composition, for example, light. It is a substance that enables the coating film to be photocured by irradiating with radiation such as. Examples of the photosensitive acid generator include (1) various onium salts such as iodonium salt, sulfonium salt, phosphonium salt, diazonium salt, ammonium salt, pyridinium salt; (2) β-ketoester, β-sulfonylsulfone and these Sulfone compounds such as α-diazo compounds of (3); (3) sulfonic acid esters such as alkyl sulfonates, haloalkyl sulfonates, aryl sulfonates, and imino sulfonates; (4) sulfones represented by the following general formula (5) Imide compounds; (5) Diazomethane compounds represented by the following general formula (6);

In the formula, X represents a divalent group such as an alkylene group, an arylene group or an alkoxylene group, and R ⁴ represents a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group or a halogen-substituted aryl group. Show.

In the formula, R ⁵ and R ⁶ may be the same as or different from each other, and represent a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group, or a halogen-substituted aryl group.

  The photosensitive acid generator can be used alone or in combination of two or more, and can also be used in combination with the thermal acid generator. The use ratio of the photosensitive acid generator in 100 parts by mass of the solid content of the liquid curable resin composition is preferably 0 to 20 parts by mass, more preferably 0.1 to 10 parts by mass. When this ratio is excessive, the strength of the cured film becomes inferior and the transparency is also lowered, which is not preferable.

(5) Surfactant A surfactant can be added to the liquid curable resin composition of the present invention for the purpose of improving applicability of the liquid curable resin composition. As this surfactant, known ones can be used. Specifically, for example, various anionic surfactants, cationic surfactants, and nonionic surfactants can be used. In particular, a cationic surfactant is preferably used so that the cured film has excellent strength and good optical properties. Furthermore, a quaternary ammonium salt is preferable, and among them, the use of a quaternary polyether ammonium salt is particularly preferable because dust wiping property is further improved. Examples of cationic surfactants that are quaternary polyether ammonium salts include Adekacol CC-15, CC-36, and CC-42 manufactured by Asahi Denka Kogyo Co., Ltd. The use ratio of the surfactant is preferably 5 parts by mass or less with respect to 100 parts by mass of the solid content of the liquid curable resin composition.

(6) Polymerization inhibitor Examples of the thermal polymerization inhibitor that can be blended in the liquid curable resin composition of the present invention include pyrogallol, benzoquinone, hydroquinone, methylene blue, tert-butylcatechol, monobenzyl ether, methylhydroquinone, Amylquinone, amyloxyhydroquinone, n-butylphenol, phenol, hydroquinone monopropyl ether, 4,4 ′-[1- [4- (1- (4-hydroxyphenyl) -1-methylethyl) phenyl] ethylidene] diphenol, Examples thereof include 1,1,3-tris (2,5-dimethyl-4-hydroxyphenyl) -3-phenylpropane. This thermal polymerization inhibitor is preferably used in an amount of 5 parts by mass or less with respect to 100 parts by mass of the solid content of the liquid curable resin composition.

(7) Solvents other than components (C) and (D) Solvents other than components (C) and (D) can be added to the liquid curable resin composition of the present invention. Such a kind and compounding quantity of a solvent can be freely selected in the range which does not impair the effect of this invention.

2. Cured film and method for producing the same The cured film of the present invention is obtained by curing the liquid curable resin composition of the present invention, and has a multilayer structure of two or more layers. In particular, it has a layer structure of two or more layers consisting of (B) one or more layers in which the metal oxide particles are present in high density and one or less layers in which the (B) metal oxide particles are substantially absent. It is preferable.

  When forming a cured film from the liquid curable resin composition of this invention, it is preferable to coat with respect to a base material (application member). As such a coating method, a dipping method, a spray method, a bar coating method, a roll coating method, a spin coating method, a curtain coating method, a gravure printing method, a silk screen method, an ink jet method, or the like can be used.

  The means for curing the liquid curable resin composition is not particularly limited, but for example, heating is preferable. In this case, it is preferable to heat at 30 to 200 ° C. for 1 to 180 minutes. By heating in this way, a cured film excellent in antireflection properties can be obtained more efficiently without damaging the substrate and the formed cured film. Preferably, it heats at 50-180 degreeC for 1 to 120 minutes, More preferably, it heats at 80-150 degreeC for 1 to 60 minutes.

Moreover, it can also be hardened | cured by irradiating a radiation by adding the above-mentioned photo-acid generator. In this case, for example, an ultraviolet irradiation device (a metal halide lamp, a high-pressure mercury lamp, or the like) can be used under a light irradiation condition of 0.001 to 10 J / cm ² , but the irradiation condition is not limited to this. . 0.01-5 J / cm ² is more preferable, and 0.1-3 J / cm ² is more preferable.

  In addition, the degree of cure of the cured film is, for example, when using a melamine compound as the curable compound, infrared spectroscopy analysis of the amount of methylol group or alkoxylated methyl group of the melamine compound, or the gelation rate, It can be confirmed quantitatively by measuring using a Soxhlet extractor.

  In the process of evaporating the solvent (C) and the solvent (D) in the composition after applying the liquid curable resin composition, (B) the metal oxide particles are applied on the coating base side (near the boundary with the adjacent layer) or its It is unevenly distributed on the opposite side. Therefore, (B) metal oxide particles are present at high density near one interface of the cured film, and (B) metal oxide particles are substantially absent near the other interface of the cured film. A resin layer having a refractive index is formed. Therefore, a cured film having a layer structure of two or more layers can be obtained by curing one coating film made of the liquid curable resin composition. Each layer formed by separation can be confirmed, for example, by observing a cross section of the obtained film with an electron microscope. (B) The layer in which the metal oxide particles are present at a high density is a concept indicating a portion where the metal oxide particles are aggregated, and is a layer substantially composed of the metal oxide particles as a main component. However, the component (A) may coexist in the layer. On the other hand, the layer substantially free of metal oxide particles is a concept indicating a portion where metal oxide particles are not present, but may be included a little as long as the effect of the present invention is not impaired. This layer is a layer substantially composed of components other than metal oxide particles such as a cured product of component (A) and component (E). In many cases, the cured film of the present invention has a two-layer structure in which a layer in which metal oxide particles are present in high density and a layer in which metal oxide particles are not substantially present form a continuous layer. When a PET resin (including a PET resin having an easy-adhesion layer) or the like is used for the base material, the layer that is the base material, the layer in which metal oxide particles are present at a high density, and the metal oxide particles are substantially Layers not present in are formed adjacent in this order.

Here, the layer structure of two or more layers refers to a case where two or more layers each including “a layer in which metal oxide particles are present at high density” and “a layer in which metal oxide particles are substantially absent” are included. In some cases, two or more layers including only two or more “layers in which metal oxide particles are present at high density” are used.
When the liquid curable resin composition contains two or more types of metal oxide particles, two or more types of “layers in which the metal oxide particles exist at high density” can be formed. Furthermore, the “metal oxide particles” of the “layer in which metal oxide particles are present at high density” means at least one, that is, one or more “metal oxide particles”. When the liquid curable resin composition contains two or more kinds of metal oxide particles, one “layer in which the metal oxide particles exist at high density” may be composed of two or more kinds of metal oxide particles. Good.

The obtained cured film preferably has a refractive index of 0.05 to 0.8, more preferably 0.1 to 0.6, in the film thickness direction. Further, it is preferable that the refractive index change has a main change in the vicinity of the boundary of the substantial two-layer structure.
The degree of change in refractive index can be adjusted by (B) content and type of metal oxide particles, (A) content and composition of fluoropolymer, and (E) content and type of curable compound. .
Moreover, the refractive index in the low refractive index part of a cured film is 1.3-1.5, for example, and the refractive index in a high refractive index part is 1.6-2.2.

3. Laminated body The laminated body of this invention is a laminated body which uses as a part of laminated structure the cured film which has the layer structure of two or more layers obtained from the liquid curable resin composition of this invention. Any two or more adjacent layers other than the base material layer constituting the laminate of the present invention can be produced as a cured film of the liquid curable resin composition of the present invention.

For example, when the substrate is a transparent substrate, the laminate of the present invention is an excellent antireflection film by providing a low refractive index layer on the outermost layer (the layer farthest from the substrate). In addition to the antireflection film, the laminate of the present invention can be used for optical parts such as a lens and a selective transmission film filter.
The specific layer configuration of the antireflection film is not particularly limited. Usually, at least a high refractive index film and a low refractive index film are laminated in this order on a base material so as to have an antireflection function. In addition to this, a hard coat layer, an antistatic layer, and the like can be included in a part of the layer structure of the laminate. Since the cured film obtained by curing the liquid curable resin composition of the present invention can form a high refractive index layer and a low refractive index layer on a substrate in one step, the manufacturing process is simplified. Can do.

  The film thickness of the cured film of the present invention in the antireflection film is, for example, 0.05 μm to 50 μm, but is not limited thereto.

  Specific examples of the transparent substrate include, for example, triacetyl cellulose, polyethylene terephthalate resin (Lumilar manufactured by Toray Industries, Inc.), glass, polycarbonate resin, acrylic resin, styryl resin, arylate resin, norbornene resin (JSR Corporation) Arton, etc.), various transparent plastic plates such as methyl methacrylate / styrene copolymer resin, polyolefin resin (Zeonex, manufactured by Nippon Zeon Co., Ltd.), and the like. Preferred are triacetyl cellulose, polyethylene terephthalate resin (Lumilar, etc. manufactured by Toray Industries, Inc.), and norbornene-based resin (Arton, manufactured by JSR Corporation).

In addition, you may interpose another layer between a base material and a cured film, for example, a hard-coat layer, a medium refractive index layer (refractive index 1.50-1.90), and a low refractive index layer ( A layer such as a combination of 1.20 to 1.55) and a high refractive index layer (1.51 to 2.20) can be provided.
An antistatic layer can also be provided. In this case, an antireflection film having antistatic properties can be obtained without adding conductive particles such as ATO particles to the cured film obtained by curing the liquid curable resin composition of the present invention. . For the antistatic layer, conductive metal oxide particles such as ATO, or a curable film to which an organic or inorganic conductive compound is added, a metal oxide obtained by vapor deposition or sputtering of the metal oxide Examples thereof include a film and a film made of a conductive organic polymer. Examples of the conductive organic polymer include polyacetylene conductive polymer, polyaniline conductive polymer, polythiophene conductive polymer, polypyrrole conductive polymer, polyphenylene vinylene conductive polymer, and the like. However, polythiophene conductive polymers such as polythiophene are preferred.
Only one of these layers may be formed, or two or more different layers may be formed.
As a coating method for these layers, a known coating method can be used, and in particular, various methods such as a dipping method, a coater method, and a printing method can be applied.

  In addition, the coating film of the liquid curable resin composition formed by coating is preferably given a heat history by heating in order to form a cured film having excellent optical properties and durability by curing. Of course, even when left at room temperature, the curing reaction proceeds with the passage of time, and the desired cured film is formed. However, in practice, curing by heating is effective in reducing the required time. Is. Moreover, the curing reaction can be further promoted by adding (F) a thermal acid generator as a curing catalyst. The heating conditions for the curing reaction can be selected as appropriate, but the heating temperature needs to be equal to or lower than the heat resistant limit temperature of the substrate to be coated.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following description, “parts” and “%” represent parts by mass and mass%, respectively, unless otherwise specified.

Production Example 1
Production of fluorinated polymer A stainless steel autoclave with an internal volume of 1.5 L with a magnetic stirrer was sufficiently replaced with nitrogen gas, and then 500 g of ethyl acetate, 43.2 g of perfluoro (propyl vinyl ether), 41.2 g of ethyl vinyl ether, hydroxyethyl vinyl ether 21.5 g, 40.5 g of “ADEKA rear soap NE-30” (Asahi Denka Kogyo Co., Ltd.) as a nonionic reactive emulsifier, and “VPS-1001” (manufactured by Wako Pure Chemical Industries, Ltd.) as an azo group-containing polydimethylsiloxane ) 6.0 g and lauroyl peroxide 1.25 g were added, and after cooling to −50 ° C. with dry ice-methanol, the oxygen in the system was removed again with nitrogen gas.

Next, 97.4 g of hexafluoropropylene was added, and the temperature increase was started. The pressure when the temperature in the autoclave reached 60 ° C. was 5.3 × 10 ⁵ Pa. Thereafter, the reaction was continued with stirring at 70 ° C. for 20 hours. When the pressure dropped to 1.7 × 10 ⁵ Pa, the autoclave was cooled with water to stop the reaction. After reaching room temperature, unreacted monomers were released and the autoclave was opened to obtain a polymer solution having a solid content concentration of 26.4%. The obtained polymer solution was put into methanol to precipitate a polymer, washed with methanol, and vacuum dried at 50 ° C. to obtain 220 g of a fluoropolymer.

  The obtained polymer had a polystyrene-reduced number average molecular weight (Mn) of 48000 by gel permeation chromatography, a glass transition temperature (Tg) of 26.8 ° C. by DSC, and a fluorine content of 50.3% by the alizarin complexone method. It was confirmed that.

Production Example 2
Silica-coated TiO ₂ particle dispersion 350 parts by mass of silica-coated titanium oxide fine powder, 80 parts by mass of ethylene oxide-propylene oxide copolymer (average degree of polymerization: about 20), 1000 parts by mass of isopropyl alcohol, 1000 parts by mass of butyl cellosolve In addition, dispersion was performed with glass beads for 10 hours, and the glass beads were removed to obtain 2430 parts by mass of silica-coated titanium oxide particle dispersion. Here, when the obtained silica-coated TiO ₂ particle dispersion was weighed on an aluminum dish and dried on a hot plate at 120 ° C. for 1 hour to obtain the total solid concentration, it was 17% by mass. Further, this silica-coated TiO ₂ particle dispersion-1 was weighed in a magnetic crucible, pre-dried on a hot plate at 80 ° C. for 30 minutes, and then fired in a muffle furnace at 750 ° C. for 1 hour. It was 82 mass% when the inorganic content in total solid content was calculated | required from the amount of residue and total solid content concentration.

Study example 1
The liquid curable resin of Compositions 1 to 5 shown in Table 1 below for the purpose of specifying the essential components for the separation of the two layers when the liquid curable resin composition is applied to the substrate and the solvent is removed. A cured film was prepared using the composition, and the layer separability was examined.
(1) Production of Liquid Curable Resin Composition (Compositions 1 to 5) 24 g of silica-coated titanium oxide dispersion obtained in Production Example 2 (solid content: 4.08 g), fluorinated polymer obtained in Production Example 1 2 g, 1.2 g of methoxylated methylmelamine “Cymel 303” (Mitsui Cytec Co., Ltd.) as a crosslinkable compound and 0.68 g of catalyst 4050 (Mitsui Cytec Co., Ltd., aromatic sulfonic acid compound) as a curing catalyst Was dissolved in 32 g of methyl ethyl ketone, 24 g of methyl isobutyl ketone, and 16 g of tertiary butanol to obtain composition 1. When the total solid content concentration in the liquid curable resin composition was measured in the same manner as in Production Example 2, it was 7.5% by mass.
Similarly, each component was mix | blended so that it might become a mixture ratio shown in following Table 1, and the compositions 2-5 were obtained. In compositions 2 to 5, normal butanol (n-BuOH) was used instead of tertiary butanol, and the composition of the solvent was methyl ethyl ketone (MEK) / isopropanol (IPA) / methyl isobutyl ketone (MIBK) / normal butanol (n -BuOH) = 40/20/30/10 was used.

(2) Production of liquid curable resin composition (Composition 6) Instead of the fluoropolymer obtained in Production Example 1, Kyner ADS (manufactured by Elf Atchem Japan Co., Ltd. Propylene hexafluoride, A liquid curable resin in the same manner as in the production of the liquid curable resin composition (Composition 1) except that a copolymer of ethylene fluoride and ethylene difluoride (having no hydroxyl group or polymerizable unsaturated group) is used. A resin composition (Composition 6) was obtained.

(2) Production of cured film Silica particle sol (methyl ethyl ketone silica sol, MEK-ST manufactured by Nissan Chemical Industries, Ltd., number average particle size 0.022 μm, silica concentration 30%) 98.6 g, 1-hydroxycyclohexyl phenyl ketone 1 g, IRGACURE907 (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, Ciba Specialty Chemicals) 1.2 g, dipentaerythritol hexaacrylate (DPHA) 33.2 g Then, 7 g of cyclohexanone was mixed and stirred to obtain a silica particle-containing composition for hard coat layer. This silica particle-containing hard coat layer composition was applied to a triacetyl cellulose film (made by LOFO, film thickness 80 μm) using a wire bar coater (# 12), and then dried in an oven at 80 ° C. for 1 minute. . Subsequently, a hard coat layer was formed by irradiating ultraviolet rays under light irradiation conditions of 0.6 J / cm ² using a high-pressure mercury lamp in the air. It was 5 micrometers when the film thickness of the hard-coat layer was measured with the stylus type film thickness meter.

  By applying composition 1-6 obtained in the above (1) on the obtained hard coat layer using a wire bar coater (# 3), and then heating in an oven at 120 ° C. for 10 minutes. A cured film layer having a thickness of 0.2 μm was formed.

(3) Evaluation of layer separation property The cross section of the obtained cured film was observed with a microscope, and it was evaluated whether or not it was separated into two layers. The evaluation criteria are as follows. A typical example of each state is shown in FIG.
<Evaluation criteria>
Two-layer separation Not separated (partially agglomerated)
Uniform structure

(4) Evaluation of haze Haze (%) measured the turbidity (Haze value) in the obtained laminated body using the Haze meter, and evaluated it based on the following reference | standard.
○: Haze value is 1% or less.
Δ: Haze value is 5% or less.
X: Haze value exceeds 5%.
The results are shown in Table 1 below.

Abbreviations in Table 1 represent the following.
(A) Fluoropolymer: The fluoropolymer produced in Production Example 1 above.
Kyner ADS: Elf Atchem Japan Co., Ltd .; copolymer of hexafluoropropylene, tetrafluoroethylene and difluoroethylene. It does not have a hydroxyl group or a polymerizable unsaturated group.
(B) Metal oxide particles Alumina, zirconia-coated TiO ₂ particle dispersion: manufactured by Teika Co., Ltd. Total solid content concentration 28%, particle concentration 24%, number average particle diameter 20 nm
Silica-coated TiO ₂ particle dispersion: produced in Production Example 2.
(E) Cymel 303: Methoxylated methylmelamine, manufactured by Mitsui Cytec Co., Ltd. (F) Catalyst 4050: manufactured by Mitsui Cytech Co., Ltd., aromatic sulfonic acid compound

From the results of Table 1, it can be seen that two-layer separation occurs even when (E) the curable compound and (F) the thermal acid generator are not blended (compositions 2 and 5).
(A) It turns out that two-layer separation does not occur when a hydroxyl group-containing fluoropolymer does not exist (Compositions 4 and 6).

Study example 2
When the liquid curable resin composition is applied to the base material and the solvent is removed, the composition of 3 and 7 to 10 shown in Table 2 below is specified for the purpose of specifying the type of the solvent that is essential for the two-layer separation to occur. Using the liquid curable resin composition, a cured film was produced in the same manner as in Examination Example 1 and under the same conditions, and the layer separability was examined.
In Study Example 2, the solvent used was changed as shown in Table 2 in the liquid curable resin composition having the solid content blending ratio of Composition 3 in Study Example 1, and layer separation and haze were evaluated.

The solubility of the (A) hydroxyl group-containing fluoropolymer is visually uniform when (A) the hydroxyl group-containing fluoropolymer is added to each solvent so as to be 50% by mass and stirred at room temperature for a fixed time. It was determined based on whether or not the solution was used, and was evaluated based on the following criteria.
<Evaluation criteria>
A: A uniform solution after stirring for 2 hours.
Δ: A uniform solution after stirring for 8 hours.
X: It is not a uniform solution after stirring for 8 hours.

(B) The dispersion stability of TiO ₂ particles is determined by immersing a glass plate in an isopropanol dispersion of (B) metal oxide particles, and (B) attaching the metal oxide particles to the glass wall. When the glass plate to which the product particles were adhered was immersed in each solvent, it was determined whether or not (B) the metal oxide particles were visually dispersed uniformly in the solvent and evaluated based on the following criteria.
<Evaluation criteria>
○: uniformly dispersed ×: not uniformly dispersed

The haze and layer separability of the cured film were evaluated in the same manner as in Study Example 1.
The results are shown in Table 2 below.

In Table 2, the solvents are arranged from left to right in order of decreasing solvent relative evaporation rate.
The abbreviations for the solvents are as follows.
MEK: Methyl ethyl ketone MeOH: Methanol IPA: Isopropanol MIBK: Methyl isobutyl ketone n-BuOH: n-butanol MAK: Methyl amyl ketone

  From the results shown in Table 2, it is preferable to add two or more solvents in order to cause two-layer separation, and at least one of them has high solubility in (C) (A) fluoropolymer, and others. It is necessary to select at least one of (D) (B) having high dispersion stability with respect to the metal oxide particles, and the relative evaporation rate of the solvent (C) is higher than the relative evaporation rate of the solvent (D). It turns out that it is necessary to be large.

  The cured film obtained by curing the liquid curable resin composition of the present invention can form a cured film having a continuous multilayer structure such as a low refractive index layer and a high refractive index layer from one coating film. Therefore, the manufacturing process of the cured film having a multilayer structure can be simplified. Therefore, the liquid curable resin composition of the present invention can be advantageously used for the formation of optical materials such as an antireflection film and a selective transmission film filter, and also has a high weather resistance by utilizing its high fluorine content. It can be suitably used as a coating material, a weather-resistant film material, a coating material, and the like for a substrate that requires properties. In addition, the cured film has excellent adhesion to the base material, high scratch resistance, and imparts a good antireflection effect. Therefore, the cured film is extremely useful as an antireflection film, and can be applied to various display devices. The visibility can be improved.

FIG. 1 is an electron micrograph showing typical examples of two-layer separation, no separation (partial aggregation), and a uniform structure.

Claims (8)

The following components (A) to (F):
(A) Fluoropolymer having a hydroxyl group in the molecule (B) One or two or more metal oxide particles (hereinafter referred to as “a”) having a number average particle diameter of 100 nm or less and a refractive index of 1.50 or more. (B) Metal oxide particles ”
(C) (A) One or two or more solvents (hereinafter referred to as “(C) fast volatile solvent”) having high solubility in a fluorine-containing polymer having a hydroxyl group in the molecule
(D) (B) one or two or more solvents (hereinafter referred to as “(D) slow volatile solvent”) having high dispersion stability with respect to the metal oxide particles and being compatible with (C) the fast volatile solvent. Called)
(E) comprises a curable compound (F) a thermal acid generator, and antireflection, characterized in that the relative evaporation rate of the (C) speed volatile solvent is greater than the relative evaporation rate of the (D) slow volatile solvent Liquid curable resin composition for film formation . (C) The fast volatile solvent is one or more solvents having low dispersion stability to (B) metal oxide particles, and (D) the slow volatile solvent has (A) a hydroxyl group in the molecule. The liquid curable resin composition for forming an antireflective film according to claim 1, wherein the liquid curable resin composition is an antireflective film-forming composition, wherein the solvent is one or more solvents having low solubility in a fluoropolymer. (B) The metal oxide particles are selected from titanium oxide, zirconium oxide, antimony-containing tin oxide, tin-containing indium oxide, aluminum oxide, cerium oxide, zinc oxide, tin oxide, antimony-containing zinc oxide, and indium-containing zinc oxide. The liquid curable resin composition for forming an antireflection film according to claim 1 or 2, wherein the liquid curable resin composition is a particle mainly composed of one or more metal oxides. The liquid curable resin composition for forming an antireflection film according to claim 3, wherein the metal oxide particles (B) are particles mainly composed of titanium oxide. The liquid curable resin composition for forming an antireflection film according to any one of claims 1 to 4, wherein the metal oxide particles (B) are metal oxide particles having a multilayer structure. A cured film obtained by curing the liquid curable resin composition for forming an antireflection film according to any one of claims 1 to 5, and having a multilayer structure of two or more layers. Wherein each layer constituting the multilayer structure, a layer or (B) metal oxide particles nonexistent layer exists at a high density (B) metal oxide particles, at least one layer, (B) metal oxide The cured film according to claim 6, which is a layer in which particles are present at a high density. A cured film comprising a step of curing the liquid curable resin composition for forming an antireflection film according to any one of claims 1 to 5 by heating or irradiation with radiation. Production method.