JP2007182511A - Coating material, method for producing the same and optical article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating material having high surface hardness, excellent in scratch resistance and having low refractive index and to provide a method for producing the coating material and to provide an optical article using the coating material. <P>SOLUTION: The coating material comprises (A) a compound having a perfluoro group, (B) silica microparticles having 40-100 nm average particle diameter and having voids in the inside and (C) porous silica microparticles having 5-30 nm average particle diameter. In the coating material, refractive index of a film obtained after coating is ≤1.365. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a low refractive index coating material excellent in scratch resistance, a method for producing the same, and an optical article using the coating material, and in particular, an antireflection film, an antireflection film, an antireflection plate, an optical filter, The present invention relates to an optical article such as an optical lens and a display, and more specifically to a technique useful in the optical field such as a front plate of various displays such as CRT, LCD, PDP, EL, and FED and a screen for rear projection.

  Low-refractive-index coating material is used as an anti-reflective coating to reduce the reflection of light sources such as external light and fluorescent lamps and improve visibility in lenses, optical components, computer and television image display devices. Used to reduce the reflection of visible light.

  As an antireflection technique, the surface of the substrate is coated with a transparent film having a low refractive index to reduce the reflectance (see, for example, Patent Document 1), and a high refractive index layer is formed on the substrate. In addition, a method of more effectively preventing reflection by forming a low refractive index layer on the upper layer is known (for example, see Patent Document 2).

  In recent years, optical articles have been increased in size and area, and many optical films have been processed with an antireflection film by a wet coating method, and attempts to lower the refractive index are also being considered. For example, an antireflective article using a fluorine-containing organic polysiloxane (for example, see Patent Document 3) or a low refractive index organic substance dissolved in a solvent, and then the substrate is coated with a low refractive index organic substance. Methods that exhibit antireflection characteristics (see, for example, Patent Documents 4 and 5) are known.

  Furthermore, in recent years, by applying a coating film forming paint obtained by dispersing silica fine particles having voids in the interior having a lower refractive index than various resins in an organic material as a matrix material, drying and curing Techniques for forming a transparent film having a low refractive index (see, for example, Patent Documents 6, 7, 8, and 9) are known. That is, in order to achieve a lower refractive index, attempts have been made to introduce a large number of silica fine particles having cavities therein.

  However, in the conventional method described above, there is a limit to the compatibility between the low refractive index property and the surface hardness, and the surface hardness is remarkably lowered when many hollow particles effective for the low refractive index are added. Further, when the amount of hollow particles added is reduced, the low refractive index property is insufficient, and there is a problem that the target low reflectance cannot be achieved when used as an antireflection film. When only porous silica is used, the effect of a low refractive index is shown with a large particle diameter, but the haze value becomes high and is not necessarily effective in improving the visibility of the display. On the other hand, when the particle size is reduced, the opening diameter of the micropores is relatively large, and the effect of low refractive index is not exhibited by filling with a matrix resin.

Therefore, the actual situation is that there is a strong demand for improving the coating agent containing a large amount of such silica fine particles.
Japanese Examined Patent Publication No. 62-58634 JP 63-81033 A Japanese Examined Patent Publication No. 6-98703 JP-A-4-355401 Japanese Patent Laid-Open No. 6-18705 JP 2002-79616 A JP 2004-83307 A JP 2004-258267 A Japanese Patent Laying-Open No. 2005-238772

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue.

  Accordingly, an object of the present invention is to provide a coating material having a high surface hardness and excellent scratch resistance and a low refractive index, a method for producing the same, and an optical article using the coating material.

  As a result of intensive studies to solve the above problems, the present inventors have surprisingly found that the low refractive index property that could not be obtained by a combination of porous silica having an average particle diameter of 5 to 30 nm and a matrix resin. The present inventors have found that the refractive index can be further reduced by using together with silica fine particles having voids in the inside of an average particle diameter of 40 to 100 nm, and the present invention has been achieved.

  That is, in order to achieve the above object, according to the present invention, (A) a compound having a perfluoro group, (B) silica fine particles having voids within an average particle diameter of 40 to 100 nm, and (C) average particles A coating material comprising porous silica fine particles having a diameter of 5 to 30 nm and having a refractive index of 1.365 or less obtained after coating is provided.

In the coating material of the present invention,
The compound (A) having a perfluoro group is a polysiloxane obtained from an organosilicon compound represented by the following general formulas (1) and (2) and / or a hydrolyzate thereof and / or a condensate thereof. ,
R ¹ —Si (R ² ) _a X _3-a (1)
(In the formula, R ¹ is an organic group having fluorine having 3 to 12 carbon atoms, R ² is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group, and a is 0 or 1.)
R ³ b-SiR ⁴ cY _{4- (b + c)} (2)
(In the formula, R ³ and R ⁴ are each an alkyl group, alkenyl group, aryl group, or a hydrocarbon group having an epoxy group, a glycidoxy group, an amino group, a methacryloxy group, or a cyano group, and Y is a hydrolyzable group. And b and c are 0 or 1, and (b + c) is 1 or 2.)
(B) the silica fine particles are hollow silica having a core-shell structure;
The preferable conditions are (C) the porosity of the porous silica fine particles is 20 to 90%, and (D) a curing catalyst containing an aluminum chelate compound.

  In the method for producing the coating material of the present invention, the (B) silica fine particles and / or the (C) porous material in a state where a part or all of the compound (A) having a perfluoro group is hydrolyzed. It has a coating liquid preparation step of mixing silica fine particles and condensing a part of each silanol group.

Furthermore, the optical article of the present invention has the above coating material laminated as a low refractive index layer on at least one surface of a transparent substrate, and has a refractive index of 1.5 to 2.0 on at least one surface. The coating material is laminated on the surface of the high refractive index layer of the coated transparent substrate provided with a high refractive index layer having a surface resistance of 1 × 10 ¹⁰ Ω / □ or less.

  According to the present invention, as described below, it is possible to obtain a coating material having a high surface hardness and excellent scratch resistance, and having a low refractive index, a method for producing the same, and an optical article using the coating material.

  The present invention will be specifically described below.

  The coating material of the present invention comprises (A) a compound having a perfluoro group, (B) silica fine particles having voids in the average particle size of 40 to 100 nm, and (C) a porous material having an average particle size of 5 to 30 nm. It is characterized in that an organic material containing silica fine particles and an inorganic material are mixed.

  As the compound (A) having a perfluoro group used in the present invention, various compounds can be applied. For example, acrylic resin, melamine resin, silicone resin, urethane resin, urea resin, epoxy resin, allyl resin, maleimide resin Phosphazene resin, fluororesin, butyral resin, silicone resin, phenol resin, vinyl chloride resin and the like. In some cases, a photopolymerizable composition can be preferably used in combination. The matrix resin used as the low refractive index layer having thermosetting properties needs to have a property of being three-dimensionally crosslinked by heating. Further, when the photopolymerization is performed after providing the low refractive index layer, a material having a light transmittance of 10% or more necessary for the photopolymerization is preferably used. As the three-dimensional crosslinking, various bonding modes such as a covalent bond, an ionic bond, and a hydrogen bond can be taken, and among them, a crosslink by a covalent bond is preferable from the viewpoint of stability to an environment such as water and oxygen. . Examples of the cross-linking by covalent bond include (thio) urethane cross-linking, melamine cross-linking, (meth) acrylic cross-linking, and polysiloxane cross-linking from the viewpoint of thermal stability. Among them, particularly from the viewpoint of improving surface hardness and antireflection properties. Polysiloxane crosslinking is preferred. In particular, in polysiloxane crosslinking, bifunctional to trifunctional organosilane compounds are preferably used from the viewpoints of surface hardness, flexibility, and the like. The organic group has an aliphatic organic group from the viewpoint that it is easy to impart a low refractive index, and from the viewpoint of improving the surface hardness, a reactive organic such as an epoxy group or a (meth) acryloyl group. Group, an alkyl group having 1 to 3 carbon atoms such as a methyl group and an ethyl group, and a vinyl group and the like as an organic group which has low reactivity but can impart a low refractive index. Moreover, it is more preferable that at least a part of the polysiloxane component is a fluorine-containing organic polysiloxane from the viewpoint of enabling a lower refractive index. As a starting material for forming such polysiloxane, each compound such as organic alkoxysilane, organic acyloxysilane, and organic halogen silane may be used as it is, but in order to achieve crosslinking at a lower temperature, each compound may be used. It is preferable to use after hydrolysis. As an example of the siloxane compound having a perfluoro group, one obtained from an organosilicon compound represented by the following general formulas (1) and (2) and / or a hydrolyzate thereof and / or a condensate thereof is preferable.

R ¹ —Si (R ² ) _a X _3-a (1)
(In the formula, R ¹ is an organic group having fluorine having 3 to 12 carbon atoms, R ² is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group, and a is 0 or 1.)
R ³ b-SiR ⁴ cY _{4- (b + c)} (2)
(In the formula, R ³ and R ⁴ are each an alkyl group, alkenyl group, aryl group, or a hydrocarbon group having an epoxy group, a glycidoxy group, an amino group, a methacryloxy group, or a cyano group, and Y is a hydrolyzable group. And b and c are 0 or 1, and (b + c) is 1 or 2.)

  Examples of the polysiloxane having a perfluoro group include trifluoroethyltrimethoxysilane, trifluoroethyltriethoxysilane, trifluoroethyltripropoxysilane, trifluoroethyltriisopropoxysilane, trifluoroethyltributoxysilane, and trifluoro. Ethyltriacetoxysilane, trifluoropropyltrichlorosilane, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, trifluoropropyltripropoxysilane, trifluoropropyltriisopropoxysilane, trifluoropropyltriacetoxysilane, trifluoropropyl Trimethoxyethoxysilane, trifluoropropylmethyldimethoxysilane, trifluoropropylmethyldiethoxy Silane, trifluoropropylethyldimethoxysilane, trifluoropropylethyldiethoxysilane, nanofluorobutylethyltrichlorosilane, nanofluorobutylethyltrimethoxysilane, nanofluorobutylethyltriethoxysilane, nanofluorobutylethyltripropoxysilane, nanofluoro Butylethyltriisopropoxysilane, nanofluorobutylethyltriacetoxysilane, nanofluorobutylethyltrimethoxyethoxysilane, nanofluorobutylethylmethyldimethoxysilane, nanofluorobutylethylmethyldiethoxysilane, nanofluorobutylethylethyldimethoxysilane, nano Fluorobutylethylethyldiethoxysilane, tridecafluorooctyltrichlorosilane, tridecaf Orooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, tridecafluorooctyltripropoxysilane, tridecafluorooctyltriisopropoxysilane, tridecafluorooctyltriacetoxysilane, tridecafluorooctyltrimethoxyethoxysilane, trideca Fluorooctylmethyldimethoxysilane, tridecafluorooctylmethyldiethoxysilane, tridecafluorooctylethyldimethoxysilane, tridecafluorooctylethyldiethoxysilane, heptadecafluorodecyltrichlorosilane, heptadecafluorodecyltrimethoxysilane, heptadecafluoro Decyltriethoxysilane, heptadecafluorodecyltripropoxysilane, heptadecafluorodecyltri Isopropoxysilane, Heptadecafluorodecyltributoxysilane, Heptadecafluorodecyltriacetoxysilane, Heptadecafluorodecyltrimethoxyethoxysilane, Heptadecafluorodecylmethyldimethoxysilane, Heptadecafluorodecylmethyldiethoxysilane, Heptadecafluorodecyl Bifunctional and trifunctional silane compounds such as ethyldimethoxysilane and heptadecafluorodecylethyldiethoxysilane are exemplified. Among these, from the viewpoint of the surface hardness and coating properties of the coating film, a compound having 3 or less fluorine atoms per molecule is preferably used. From the viewpoint of chemical resistance and antifouling property, a compound having 13 or more fluorine atoms per molecule can be preferably used. Moreover, it is also preferable to use two or more types of compounds represented by the general formula (1) depending on the object to be coated and the coating method. These may be copolymerized at the same time, and those separately polymerized may be mixed and used later as appropriate.

  Examples of the silane compound represented by the general formula (2) include methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltripropoxysilane, methyltributoxysilane, Ethyltrimethoxysilane, ethyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octadecyltrichlorosilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri Acetoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyl Methoxyethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltriacetoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-aminopropyl Trimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, β-cyanoethyltriethoxy Silane, methyltriphenoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, α-glycid Cyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α-glycidoxypropyltrimethoxysilane, α-glycid Xylpropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycid Xylpropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyltrimethoxysilane, α-glycyl Sidoxybutyl tri Toxisilane, β-glycidoxybutyltrimethoxysilane, β-glycidoxybutyltriethoxysilane, γ-glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ-glycidoxybutyltrimethoxy Silane, δ-glycidoxybutyltriethoxysilane, (3,4-epoxycyclohexyl) methyltrimethoxysilane, (3,4-epoxycyclohexyl) methyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltripropoxysilane, β- (3,4-epoxycyclohexyl) ethyltributoxysilane, β- (3,4-epoxycyclo Xyl) ethyltrimethoxyethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriphenoxysilane, γ- (3,4-epoxycyclohexyl) propyltrimethoxysilane, γ- (3,4-epoxycyclohexyl) propyltri Ethoxysilane, δ- (3,4-epoxycyclohexyl) butyltrimethoxysilane, δ- (3,4-epoxycyclohexyl) butyltriethoxysilane, 3- (N, N-diglycidyl) aminopropyltrimethoxysilane, 3- Glycidoxypropyltrimethoxysilane, cyanoethyltrichlorosilane, cyanopropyltrichlorosilane, cyanopropyltrimethoxysilane, dimethyldichlorosilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiacetoxy , Phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ -Aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, glycidoxymethylmethyldimethoxysilane Glycidoxymethylmethyldiethoxysilane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyldiethoxysilane, β-glycidyl Doxyethylmethyldimethoxysilane, β-glycidoxyethylmethyldiethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropylmethyldiethoxysilane, β-glycidoxypropylmethyldimethoxysilane, β -Glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldi Butoxysilane, γ-glycidoxypropylmethyldimethoxyethoxysilane, γ-glycidoxypropylmethyldiphenoxysilane, γ-glycidoxypropylmethyldiacetoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ Glycidoxypropylethyldiethoxysilane, γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyldiethoxysilane, γ-glycidoxypropylphenyldimethoxysilane, γ-glycidoxypropylphenyldiethoxysilane , Diethyldichlorosilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, cyclohexylmethyldimethoxysilane, octadecyl Examples thereof include methyldimethoxysilane, octadecylmethyldimethoxysilane, and octadecylmethyldiethoxysilane.

  It is not a problem that the above silane compounds are used alone or in combination of two or more. In addition, in such polysiloxane crosslinks, tetrafunctional silanes, specifically tetramethoxysilane, tetraethoxysilane, tetrapropoxy, can be easily used in combination with other silane compounds because the surface hardness can be easily increased. Silane, tetrabutoxysilane, tetraacetoxysilane and the like are also preferably used.

  In the present invention, it is desirable that the compound having a perfluoro group and the silica fine particles have a reactive group for allowing them to react with each other, and the dispersion stability of the silica fine particles can be further improved.

  Acid catalysts used for the hydrolysis reaction of these silane compounds include formic acid, succinic acid, hydrochloric acid, sulfuric acid, acetic acid, trifluoroacetic acid, phosphoric acid, polyphosphoric acid, polyvalent carboxylic acid or anhydrides thereof, ion exchange resins, etc. An acid catalyst is mentioned. In particular, formic acid and acetic acid are preferably used as catalysts from the viewpoint of improving the hardness of the coating film.

  The addition amount of the acid catalyst is preferably 0.05% by mass to 10% by mass, and more preferably 0.1% by mass to 5% by mass with respect to the total silane compound content used. If the amount of the acid catalyst is less than 0.05% by mass, the hydrolysis reaction may not proceed sufficiently. If the amount exceeds 10% by mass, the hydrolysis reaction may run away.

  It is also possible to utilize the residual acid in the silanol reaction solution obtained by hydrolyzing one of the silane compounds, and mix the remaining silane compound and water and hydrolyze under any reaction conditions. There is no problem in efficiently synthesizing using the difference in sex.

  The solvent used in the hydrolysis and polycondensation reaction is preferably an organic solvent, such as methyl alcohol, ethyl alcohol, propyl alcohol, iso-propyl alcohol, butyl alcohol, t-butyl alcohol, sec-butyl alcohol, diacetone alcohol, benzyl. Alcohols such as alcohol, phenethyl alcohol, 3-methyl-3-methoxy-1-butanol; glycols such as ethylene glycol and propylene glycol; ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono Propyl ether, propylene glycol monobutyl ether, propylene glycol mono-t-butyl ether, diethyl ether, etc. Ethers; ketones such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone; amides such as dimethylformamide and dimethylacetamide; acetates such as ethyl acetate, ethyl cellosolve acetate, 3-methyl-3-methoxy-1-butanol acetate; In addition to aromatic or aliphatic hydrocarbons such as toluene, xylene, hexane, and cyclohexane, γ-butyrolactone, N-methyl-2-pyrrolidone, dimethyl sulfoxide, and the like can be given.

  The amount of the solvent used in the synthesis of the polysiloxane compound is preferably added in the range of 50% by mass to 500% by mass, particularly preferably in the range of 80% by mass to 200% by mass, based on the total silane compound content. It is. If it is less than 50% by mass, the reaction may run away and gel. On the other hand, if it exceeds 500 mass%, hydrolysis may not proceed.

  The water used for the hydrolysis is preferably purified such as distilled water. The amount of water can be arbitrarily selected, but it is preferably used in the range of 1.0 to 4.0 mol with respect to 1 mol of silane.

  In producing the coating material of the present invention, the hydrolysis reaction is carried out by adding the silica fine particles of (B) and (C), an acid catalyst and water in a solvent, and the perfluoro group of (A). It is preferable to carry out at the same time as the polysiloxane having from the viewpoint that the dispersion stability of the obtained paint can be further improved. As conditions for the hydrolysis polycondensation reaction, it is preferable to carry out hydrolysis at room temperature to 55 ° C. to obtain a silanol compound, and then carry out the reaction solution as it is under reflux for 1 to 100 hours. In addition, after polycondensation of different silanol compounds at any temperature, they can be further mixed and copolymerized under any conditions. There is no problem in efficiently synthesizing using the difference in different polymerizability. . In addition, in order to increase the degree of polymerization of the polysiloxane, it is possible to reheat or add a base catalyst. Further, in consideration of storage stability, it may be diluted to an arbitrary solid content concentration using a solvent after the condensation reaction.

  In the polysiloxane having a perfluoro group (A) used in the present invention, the above general formula (1) and general formula (2) can be copolymerized in advance without any problem. As a ratio of the copolymer, the total molar amount of the silane compound represented by the general formula (2) is preferably 0.1 to 100 moles with respect to 1 mole of the silane compound represented by the general formula (1). More preferably, 1 to 10 mol is used.

  On the other hand, the use of a resin other than the polysiloxane having a perfluoro group of the present invention can also be selected depending on the intended use and processing conditions of the obtained coating material. For example, an acrylic resin, a melamine resin, a silicone resin, a urea resin, an allyl resin, a maleimide resin, a phosphazene resin, and the like can be given, and in some cases, a photopolymerizable composition can be preferably used in combination.

  The polymer having a photopolymerizable reactive group is a polymer having an unsaturated double bond as a reactive group, and a polymer containing a phenolic hydroxyl group or a carboxyl group is once polymerized by utilizing a known radical polymerization reaction. It can be obtained by adding an epoxy group-containing (meth) acrylate, or by once polymerizing an epoxy group-containing polymer and adding a phenolic hydroxyl group or carboxyl group-containing (meth) acrylate. Further, from the viewpoint of dispersion stability of the silica-based fine particles, the silica-based fine particles having a reactive group are once mixed with a reactive polymer having a photopolymerizable group, and then the copolymer of the present invention is added to the present invention. Coating material can be obtained.

  The polymer having a phenolic hydroxyl group or a carboxyl group or an epoxy group-containing polymer of the present invention is a homopolymer polymer of a radical polymerizable monomer having these groups and / or the radical polymerizable monomer and other radicals other than that. The copolymer monomer of the polymerizable monomer can be obtained by polymerization by a known method using a radical polymerization initiator.

  Examples of the radical polymerizable monomer having a phenolic hydroxyl group or a carboxyl group include o-hydroxystyrene, m-hydroxystyrene and p-hydroxystyrene, and alkyl, alkoxy, halogen, haloalkyl, nitro, cyano, amide, and ester thereof. Carboxy substitution products; polyhydroxyvinylphenols such as vinyl hydroquinone, 5-vinyl pyrogallol, 6-vinyl pyrogallol, 1-vinyl phloroglicinol; o-vinyl benzoic acid, m-vinyl benzoic acid, and p-vinyl benzoic acid As well as their alkyl, alkoxy, halogen, nitro, cyano, amide, ester substituents, methacrylic acid and acrylic acid, and their α-position haloalkyl, alkoxy, halogen, nitro, Substituted substances: divalent unsaturated carboxylic acids such as maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, citraconic acid, mesaconic acid, itaconic acid and 1,4-cyclohexenedicarboxylic acid, and their methyl, ethyl, Preference is given to propyl, i-propyl, n-butyl, sec-butyl, ter-butyl, phenyl, o-, m-, p-toluyl half ester and half amide. Of these, o-hydroxystyrene, m-hydroxystyrene and p-hydroxystyrene, and acrylic acid and methacrylic acid are preferably used. These can be used alone or in combination of two or more.

  Examples of the radical polymerizable monomer having an epoxy group include glycidyl acrylate and glycidyl methacrylate.

  Examples of the other radical polymerizable monomers include styrene and alkyl, alkoxy, halogen, haloalkyl, nitro, cyano, amide, ester at α-position, o-position, m-position, or p-position of styrene. Substituted substances; Diolefins such as butadiene, isoprene, chloroprene; methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, ter-butyl, pentyl, neopentyl, isoamylhexyl methacrylate or acrylic acid , Cyclohexyl, adamantyl, allyl, propargyl, phenyl, naphthyl, anthracenyl, anthraquinonyl, piperonyl, salicyl, cyclohexyl, benzyl, phenethyl, cresyl, 1,1,1-trifluoroethyl, perfluoroethyl, perfluoro-n-p Lopyl, perfluoro-i-propyl, triphenylmethyl, tricyclo [5.2.1.02,6] decan-8-yl (commonly referred to as “dicyclopentanyl” in the art) , Cumyl, 3- (N, N-dimethylamino) propyl, 3- (N, N-dimethylamino) ethyl, furyl, furfuryl ester, anilide of methacrylic acid or acrylic acid, amide, or N, N- Dimethyl, N, N-diethyl, N, N-dipropyl, N, N-diisopropyl, anthranilamide, acrylonitrile, acrolein, methacrylonitrile, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinyl pyrrolidone, Vinylpyridine, vinyl acetate, N-phenylmaleimide, N- (4-hydroxyphenyl) malein Imide, N-methacryloylphthalimide, N-acryloylphthalimide, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ -Acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldimethoxysilane, and the like can be used. Among these, when low refractive index is considered, each ester of methacrylic acid or acrylic acid 1,1,1-trifluoroethyl, perfluoroethyl, perfluoro-n-propyl, perfluoro-i-propyl Compounds are preferred.

  In consideration of the adhesiveness of the copolymer of the present invention, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyl Dimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldimethoxysilane and the like are preferable. These can be used alone or in combination of two or more.

  When using a copolymer of a radically polymerizable monomer having a phenolic hydroxyl group or a carboxyl group, a radically polymerizable monomer having an epoxy group, and other radically polymerizable monomers other than that, preferred copolymerization of the radically polymerizable monomer The ratio of the radical polymerizable monomer having a phenolic hydroxyl group or a carboxyl group is preferably 5 to 50% by mass, particularly preferably 5 to 40% by mass, based on the total amount with the radical polymerizable monomer. Moreover, the radically polymerizable monomer which has an epoxy group becomes like this. Preferably it is 5-50 mass%, Most preferably, it is 5-40 mass%.

  In addition, various curing agents and three-dimensional crosslinking agents can be added to these compositions for the purpose of accelerating curing or for the purpose of facilitating curing. Specific examples thereof include nitrogen-containing organic substances, silicone resin curing agents, various metal alcoholates, various metal chelate compounds, isocyanate compounds and polymers thereof, melamine resins, polyfunctional acrylic resins, urea resins, and the like. Two or more kinds may be added.

  When the photopolymerizability is used in combination with the coating material of the present invention, the amount of the polymer having a polymerizable reactive group is preferably 2% by mass to 20% by mass, more preferably 5%, based on the content of the matrix resin composition. It is mass%-15 mass%. If the amount is less than 2% by mass, photopolymerization may not occur. If the amount exceeds 40% by mass, a separation phenomenon from the mixed polysiloxane may occur and a smooth coating film may not be obtained.

  In the silica-based fine particles used in the present invention, a reactive group can be selected according to the polymerizability of polysiloxane. It is preferable to use particles having a silanol group or the like on the surface as the reactive group in the case where the thermal polymerizability is increased. Moreover, when photopolymerizability is improved, it is preferable to use what modified the particle | grain surface by processing with the surface modifier containing silane coupling agents, such as a methacryl group, an acryl group, and a mercapto group. Moreover, it is also possible to modify the particle surface as necessary.

  Examples of the silica fine particles having voids inside the average particle diameter of 40 to 100 nm used in the present invention include hollow silica having a core-shell structure and silica fine particles having pores on the surface and inside of the silica fine particles. Among these silica fine particles, hollow silica fine particles having a core-shell structure are preferably used from the viewpoint of the stability of the coating material. Since the hollow silica fine particles have a refractive index of 1.20 to 1.40, the effect of lowering the refractive index of the coating film by introduction is great. In order to efficiently reduce the refractive index, it is necessary to use silica-based fine particles having an average particle diameter of 40 nm to 100 nm. A preferable range of the average particle diameter is 40 nm to 60 nm. When the average particle diameter is less than 40 nm, the refractive index is not sufficiently lowered. When the average particle diameter is more than 100 nm, the film may become white or the surface unevenness may be increased.

  Here, the core-shell structure means that the central portion and the outer peripheral portion have different compositions in a spherical shape, and the outer shell portion is formed so as to cover the small spherical shape inside. . The inside is not limited to a solid, but a gas or liquid is called a core, and an outer shell is called a shell.

  The porous silica fine particles (C) having an average particle diameter of 5 to 30 nm used in the present invention preferably have a porosity in the range of 20 to 90%, more preferably in the range of 30 to 70%. . If the porosity is less than 20%, the effect of lowering the refractive index is small, and if it exceeds 90%, mixing with the matrix resin becomes difficult. The surface pore diameter is preferably 10 nm or less so that the matrix resin does not enter the silica fine particles. Since the porous silica fine particles have a refractive index of 1.35 or less, the introduction has a great effect of reducing the refractive index of the coating film. For the purpose of introduction, it is possible to use a modified particle surface treated with a surface modifier containing a silane coupling agent for the purpose of preventing secondary aggregation of the particles. If the average particle size is less than 5 nm, the number of internal pores is small and it is impossible to maintain a porosity of 20% or more, and if it exceeds 30 nm, mixing with silica fine particles having voids inside becomes difficult. A preferable range of the average particle diameter is 15 to 30 nm.

  In the present invention, when (B) silica fine particles having voids in an average particle diameter of 40 to 100 nm and (C) porous silica fine particles having an average particle diameter of 5 to 30 nm are introduced into the coating material, the coating material is obtained. In addition to the refractive index of the coating film obtained from 1.35 or less, the hardness of the coating film can be increased. The amount of each silica-based fine particle introduced is preferably 20% by mass to 70% by mass and more preferably 30% by mass to 60% by mass with respect to the solid content of the inorganic fine particles and the matrix resin component in the coating material. When the amount introduced is less than 20% by mass, the refractive index lowering effect due to the voids of the particles is small, and the refractive index does not become 1.365 or less. On the other hand, if it exceeds 70% by weight, the hardness of the transparent film may be lowered due to the unevenness caused by excess particles that do not fit inside the layer, and the refractive index may be uneven depending on the location.

  The mixing ratio of the silica fine particles (B) and the silica fine particles (C) is preferably 0.7 or more and more preferably 0.9 or more in terms of (B) / (C) weight ratio. If it is less than 0.7, the low refractive index property of the porous silica cannot be maintained, and the refractive index of the coating film becomes large.

  The coating material of the present invention may further contain various (D) curing agents or three-dimensional crosslinking agents that make curing easier. Specific examples of (D) curing agents include nitrogen-containing organic substances, silicone resin curing agents, various metal alcoholates, various metal chelate compounds, isocyanate compounds and polymers thereof, melamine resins, polyfunctional acrylic resins, urea resins, and the like. These may contain one kind or two or more kinds. Of these, metal chelate compounds are preferably used in view of the stability of the curing agent and the processability of the obtained coating film. Examples of the metal chelate compound used include a titanium chelate compound, a zirconium chelate compound, an aluminum chelate compound, and a magnesium chelate compound. Among these, an aluminum chelate compound is preferable in terms of low refractive index and stability. The chelate compound can be easily obtained by reacting a metal alkoxide with a chelating agent. Examples of chelating agents include β-diketones such as acetylacetone, benzoylacetone, and dibenzoylmethane; β-keto acid esters such as ethyl acetoacetate and ethyl benzoylacetate. Preferable specific examples of the metal chelate compound include monoethoxy-, mono-n-propoxy-, mono-i-propoxy-, mono-n-butoxy-, mono-s-butoxy-, mono-t-butoxytrisacetylacetate titanium, diethoxy -, Di-n-propoxy-, di-i-propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxybisacetyl acetate titanium, triethoxy-, tri-n-propoxy-, tri-i-propoxy, Tri-n-butoxy-, tri-s-butoxy-, tri-t-butoxy monoacetylacetate titanium, monoethoxy-, mono-n-propoxy-, mono-i-propoxy, mono-n-butoxy-, mono-s-butoxy-, mono t-butoxy tris ethyl acetoacetate titanium, diethoxy-, di-n-propoxy-, di-i Propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxybisethyl acetoacetate titanium, triethoxy-, tri-n-propoxy-, tri-i-propoxy-, tri-n-butoxy-, tri-s-butoxy -, Tri-t-butoxy monoethyl acetoacetate titanium, monoethoxy-, mono-n-propoxy-, mono-i-propoxy-, mono-n-butoxy-, mono-s-butoxy-, mono-t-butoxytrisacetylacetate zirconium, diethoxy -, Di-n-propoxy-, di-i-propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxybisacetylacetate zirconium, triethoxy-, tri-n-propoxy-, tri-i-propoxy, Tri-n-butoxy-, tri-s-butoxy-, tri-t-butoxy monoa Zyl acetate zirconium, monoethoxy-, mono n-propoxy, mono i-propoxy, mono n-butoxy, mono s-butoxy, mono t-butoxy trisethyl acetoacetate zirconium, diethoxy-, di n-propoxy- Di-propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxybisethyl acetoacetate zirconium, triethoxy-, tri-n-propoxy-, tri-i-propoxy-, tri-n-butoxy, Tris-butoxy-, tri-t-butoxymonoethylacetoacetate zirconium, monoethoxy-, mono-n-propoxy-, mono-i-propoxy-, mono-n-butoxy-, mono-s-butoxy-, mono-t-butoxybisacetyl Acetate aluminum, diethoxy-, di-n-propoxy Si-, di-i-propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxy monoacetylacetate aluminum, monoethoxy-, mono-n-propoxy-, mono-i-propoxy-, mono-n-butoxy -, Mono-s-butoxy-, mono-t-butoxybisethylacetoacetate aluminum, diethoxy-, di-n-propoxy-, di-i-propoxy-, di-n-butoxy-, di-s-butoxy-, di-t-butoxy mono Ethyl acetoacetate aluminum, monoethoxy monoacetyl acetate magnesium, monoethoxy monoethyl acetoacetate magnesium, acetylacetonate titanium, ethyl acetoacetate titanium, acetylacetonate zirconium, acetate zirconium, ethyl acetate zirconium, acetyl Metal chelates such as cetonate aluminum, ethyl acetoacetate aluminum, monoacetyl acetate bisethyl acetate aluminum, bisacetyl acetate monoethyl acetoacetate aluminum, acetylacetonate magnesium, ethyl acetoacetate magnesium, acetylacetonate iron, acetylacetonate tin, Examples include alkyl acetoacetate compounds. In view of storage stability and availability, acetylacetonate aluminum, ethyl acetoacetate aluminum, and monoacetyl acetate bisethyl acetate aluminum are preferable.

  The content of these (D) curing agents is preferably 0.1 to 10 parts by weight, particularly preferably 1 part by weight, based on 100 parts by weight of the total amount of the compound having a perfluoro group and silica fine particles. ~ 6 parts by weight.

  The optical article of the present invention is obtained by laminating the coating material as a low refractive index layer on at least one surface of a transparent substrate to form a film.

  As a method of forming a film from the coating material of the present invention, there is a method of coating using microgravure coating, spin coating, dip coating, curtain flow coating, roll coating, spray coating, flow coating method, etc. From the viewpoint of uniformity of prevention, that is, prevention of unevenness of reflected light color, microgravure coating is particularly preferably used. Using such a method, it is applied onto a substrate, and is heated, dried and cured as required. The heating and drying method should be determined by the applied substrate and coating components, but is usually treated at a temperature of room temperature to 300 ° C, usually for 0.5 to 240 minutes. Various surfactants can be used to improve the flowability during coating. In particular, in addition to the flow property, the addition of a fluorosurfactant is preferable from the viewpoint that the anti-staining film can be further prevented from being contaminated.

  When a photopolymerizable material is used, a film is formed by irradiating ultraviolet rays having a wavelength shorter than that in the visible region after the coating film is formed, simultaneously with heating, drying and curing and / or after heating, drying and curing. May be. In this case, ultraviolet irradiation acts not only on the curing reaction of the surface layer but also on the remaining reactive groups of the coating film laminated on the lower layer, thus improving adhesion with the coating material of the present invention and improving chemical resistance. effective. In particular, a high effect can be obtained when the lower coating film is of an ultraviolet curable type.

  The coating material of the present invention may be applied directly on a transparent substrate and cured to form a coating film. However, when this coating film is used as a low refractive index layer, the object is to further improve the antireflection property. For this reason, it is preferable to provide a coating film on a base material provided with a high refractive index layer having a higher refractive index of 0.05 to 0.55 than that of the low refractive index layer. The refractive index having a high refractive index is preferably from 1.5 to 2.0, more preferably from 1.55 to 1.75. If it is less than 1.5, the antireflection property is insufficient, and if it is more than 2.0, the effect of the low refractive index layer is not sufficiently exhibited. Furthermore, in addition to high refractive index performance, it is a layer that has both hard coat performance that increases surface hardness, imparts toughness and scratch resistance, reduces the number of coatings, and cheaper articles It is more preferable from the viewpoint that can be provided.

In general, the fluorine-containing organic polysiloxane coating film has a problem that it is easily charged and is likely to be dusty. In order to solve such a problem, as the material for the high refractive index layer, a composition having ultraviolet curability is preferably used from the viewpoints of adhesion to a fluorine-containing organic polysiloxane-based film, after-curing property, and the like. At the same time, those containing metal oxide fine particles typified by ITO, ATO, ZnO ₂ , SnO ₂ , and Sb ₂ O ₅ , or those containing a conductive polymer made of an organic substance are desirable.

  Examples of the conductive polymer made of an organic material include polyacetylene, polythiophene, poly (3-alkyl) thiophene, polypyrrole, polyisothiaphthalene, polyethylenedioxythiophene, poly (2,5-dialkoxy) paraphenylene vinylene, polyparaphenylene. , Polyheptadiyne, poly (3-hexyl) thiophene, polyaniline and the like.

  As a preferable resin component having such ultraviolet curability, a polyfunctional (meth) acrylic compound containing at least two (meth) acryloyl groups in the molecule can be exemplified. Specific examples of these compounds include mono-, di-, or triethylene glycol di (meth) acrylate, mono-, di-, or tripropylene glycol di (meth) acrylate, glycerin di-, or tri (meth) acrylate. , Trimethylolpropane di- or tri (meth) acrylate, tetramethylolmethane di-, tri- or tetra- (meth) acrylate, pentaerythritol, di- or tri- (meth) acrylate, neopentylglycol di- (meth) ) Aliphatic polyfunctional (meth) acrylate compounds such as acrylate, sorbitol di-, tri-, tetra-, or hepta (meth) acrylate, as well as bisphenol A-, or bisphenol F-ethylene oxide adducts, or di- ( (Meth) acrylate An aromatic ring-containing polyfunctional (meth) acrylate compound such as is also preferably used. Furthermore, it is also possible to add a compound having a polymerizable unsaturated group and an alkoxysilane group in the molecule.

In the high refractive index layer, a combination of various metal oxides is also preferably used for the purpose of further increasing the refractive index and antistatic. Examples of the metal oxide preferably used include metal oxides selected from the group consisting of zirconium, indium, antimony, zinc, tin, cerium and titanium having a particle diameter of 5 nm to 100 nm, and composite oxides thereof. Among them, a composite oxide (ITO) composed of indium and tin, or a composite oxide composed of tin and antimony (ATO) can impart conductivity in addition to increasing the refractive index, and can provide antistatic properties. It is preferably used from the viewpoint. In particular, from the viewpoint of antistatic, the surface resistance is preferably 1 × 10 ¹⁰ Ω / □ or less, more preferably 1 × 10 ⁸ Ω / □ or less.

  Further, in the case where a high refractive index layer is provided, the film thickness of the high refractive index layer is about 0.5 μm to 10 μm, more preferably 1 to 6 μm, in view of antireflection effect and hard coat film performance. Is particularly preferred.

  In the present invention, as a layer containing a near-infrared absorbing compound or a dye, it can be coated on a transparent substrate or bonded to be used for various displays. Generally, a near-infrared absorbing compound is unstable with respect to heat. For example, when it is blended in a transparent base material and molded, there is a possibility that it is deteriorated by heating. It is preferable to use it in a hard coat agent or an adhesive layer.

  For example, as a commonly used method, a transparent molded body in which a layer containing a near-infrared absorbing compound or a dye (NIR layer) is laminated is prepared in advance, and a low refractive index layer made of the coating material of the present invention is prepared. A method of pasting the transparent molded body having the adhesive layer through an adhesive layer is performed. In order to reduce the cost increase due to coating or bonding, it is preferable to use as the NIR layer an adhesive layer provided on the surface of the transparent substrate having a low refractive index layer on which the low refractive index layer is not laminated. . In addition, as a method of laminating the NIR layer, for example, low refractive index layer (LR) / high refractive index layer (HR) / transparent substrate / NIR layer, LR / HR / NIR layer / transparent substrate, LR / HR− Examples include NIR layer / transparent substrate, LR / HR / transparent substrate / bonding adhesive layer / transparent substrate / NIR layer, and the like.

  Near-infrared absorbing compounds include anthraquinone compounds, phthalocyanine compounds, naphthalocyanine compounds, metal oxide fine powders, imonium compounds, diimonium compounds, aminium salt compounds, thiourea compounds, bisthiourea compounds, and square acid compounds. And metal complex compounds. More specifically, cyanine dyes, merocyanine dyes, (thio) pyrylium dyes, naphtholactam dyes, pentacene dyes, oxyindolizine dyes, quinoid dyes, aminium dyes, diimmonium dyes, indoaniline dyes, nickel thio complex dyes, and the like.

  Further, the dye can be used by being added to the same layer as the near infrared absorbing compound or in another layer. It is preferable to select a dye that has little absorption of the three primary colors of light emitted from each display. Particularly in an optical filter for PDP, red color purity and color reproducibility can be improved by cutting a wavelength around 595 nm, which is called neon light. Examples of the dye used in the present invention include cyanine compounds, oxonol compounds, triphenylmethane compounds, diphenylmethane compounds, xanthene compounds, thiazine compounds, and the like. Also, the contrast can be improved by using various dyes to achieve neutral gray. Examples of the dye having little absorption of the three luminescent primary colors include squarylium, cyanine, azo, azomethine, oxonol, benzylidene, xanthene, and metrocyanine.

  The optical article of the present invention thus obtained has a high surface hardness, excellent scratch resistance, and a low refractive index surface, so that it has an antireflection film, an antireflection film, an antireflection plate, an optical filter, It is useful for optical articles such as optical lenses and displays, more specifically, for example, front plates of various displays such as CRT, LCD, PDP, EL, and FED, and screens for rear projection.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

  The optical article obtained in each Example / Comparative Example is used as a sample, and the characteristic measurement method and performance evaluation method of each sample are shown below.

[Measurement of refractive index]
A 1.5 μm-thick coating film formed on a silicon wafer was perpendicular to the film surface at 633 nm (using a He—Ne laser) at 20 ° C. using a prism coupler (manufactured by Metricon). The refractive index was measured.

[Measurement of light reflectance]
Measurement was performed using a spectrophotometer 3410 of Hitachi Instrument Service Co., Ltd. The sample is # 320-400 water-resistant sandpaper, the surface opposite to the coating film surface is evenly scratched, black paint (black magic ink (registered trademark) liquid) is applied, and the coating film surface is opposite The measurement was performed by completely eliminating reflection from the side surface and pressing the surface to be measured against an integrating sphere. The incident angle was 10 °, and the inspection wavelength region was 380 nm to 800 nm. The light reflectance was expressed as a minimum value.

[Hardness evaluation]
A load of 250 gf / cm ² was applied to the coating film surface of each sample using # 0000 steel wool, and the number of scratches after 10 reciprocations was observed and evaluated according to the following criteria. Scratch resistance is good if it is grade 3, 4, 5.
5th grade: No scratch 4th grade: 1-5 scratches 3rd grade: 6-10 scratches 2nd grade: 11 or more scratches 1st grade: Full scratches.

[Fingerprint wiping property (antifouling resistance evaluation)]
A finger is pressed against the forehead for 2 seconds, and the finger is applied to the coating film surface of each sample for 5 seconds to attach a fingerprint, and then the attached fingerprint is folded in half with Kimwipe (Crecia Wiper S-200). It was pressed using 10 pieces, wiped by 10 rotations, and its removability was evaluated visually. The evaluation is “○” for scars that are hardly noticeable and easily wiped off, “△” for those that remain slightly and difficult to wipe, and “×” for those that are markedly traced and cannot be wiped off at all. did.

[Measurement of surface resistance]
The surface resistance value was measured in a room temperature atmosphere using HIRESTA manufactured by Mitsubishi Yuka Co., Ltd.

[Measurement of average particle diameter of silica fine particles]
In the case of a raw material, the measurement was performed using a dynamic light scattering particle size distribution measuring device LB-500 manufactured by Horiba, Ltd. However, the actual refractive index may not be shown because it has voids and has a refractive index close to that of the solvent. In that case, the cross section of the coating film was observed with a transmission electron microscope, and the diameter of representative (most common) particles was measured from the obtained image.

Example 1
[High refractive index layer]
A PET film (thickness 100 μm, with an easy adhesion layer, manufactured by Toray Industries, Inc.) was used as a transparent substrate. On top of this, AS-41 (manufactured by Dainichi Seika Co., Ltd.) with a solid content concentration of 30% is hand-coated with a metalling bar, and a 12th-number metallizing bar is used to form an A4 size transparent substrate 3 cc of the coating solution was dropped and applied with a metering bar while taking care not to introduce bubbles.

[Method of curing high refractive index layer]
After coating by the above method, it was immediately placed in an oven at 80 ° C. and heat-treated for 1 minute. Thereafter, an ultraviolet irradiation treatment (about 300 mJ / cm ² when converted to ultraviolet rays) was performed on a conveyor type UV irradiation apparatus equipped with one high-pressure mercury lamp (120 W) at a speed of 5 m / min. Thus, a substrate with a high refractive index layer coating was obtained. The film thickness after drying and curing was about 3 μm. The surface resistance value was 1.1 × 10 ⁹ Ω / □.

[Low refractive index layer]
The obtained high refractive index layer-coated substrate was provided with a low refractive index layer made of the following coating material.

[Method of preparing coating material]
4.15 g of tridecafluorooctyltrimethoxysilane (manufactured by Toshiba Silicone Co., Ltd.) and 19 g of isopropyl alcohol were placed in the flask, and 1.03 g of formic acid aqueous solution prepared to 2.0 N was stirred while being dropped over about 10 minutes. After completion of the dropwise addition, the temperature was adjusted to 50 to 55 ° C. and stirred for 2 hours. Next, 3.89 g of methyltrimethoxysilane (manufactured by Shin-Etsu Silicone) and 26.6 g of propylene glycol monoethyl ether were added, and then 1.54 g of purified water was dropped and mixed at 20 to 25 ° C. over about 10 minutes. . Subsequently, the mixture was heated to 60 ° C. and stirred and reacted for 2 hours. Next, after cooling to room temperature, 10.4 g of isopropyl alcohol was added to adjust the concentration to obtain a copolymer solution (A).

  Next, 53.16 g of methyltrimethoxysilane (manufactured by Shin-Etsu Silicone) and 38.31 g of trifluoropropyltrimethoxysilane (manufactured by Shin-Etsu Silicone) were added to the flask, and 100 g of propylene glycol monoethyl ether was added as a solvent. 104.53 g of isopropyl alcohol-dispersed hollow silica sol (Catalyst Kasei Chemical Industry Co., Ltd., solid content 20.5% by mass, particle size about 50 nm), porous silica sol (Osaka Sumitomo Cement Co., Ltd., silica sol, particle size about 25 nm, void 214.29 g of about 40% rate and 10% solids) was added. Thereafter, the temperature was set to about 20 ° C., and 30.66 g of a formic acid aqueous solution prepared to 1.0 N was added over about 20 minutes while stirring with a stirring spring at a rotational speed of about 270 rpm, and subsequently using an oil bath. The temperature of the reaction solution was set to 60 ° C. and stirred for 3 hours to complete the reaction, and the reaction solution was cooled to room temperature to obtain a silica fine particle solution reacted with polysiloxane.

  The copolymer (A) and the silica fine particle solution are mixed, and 363.3 g of methyl alcohol, 2058 g of isopropyl alcohol, and 600 g of propylene glycol monoethyl ether are added, and then 4.0 g of trisacetylacetonate aluminum is added and dissolved by stirring. Coating material.

  The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in the coating material was 55 parts by weight / 22.5 parts by weight / 22.5 parts by weight. The ratio of the curing agent to 100 parts by weight in total was 4 parts by weight.

[Coating material application method]
Using the prepared coating material, apply 1.5cc of coating solution by hand coating to the substrate with high refractive index layer coating by using a 6th metal ring bar and apply while taking care not to get bubbles. did. The film thickness was about 100 nm.

[Coating film curing method]
Immediately after applying the coating material, it was placed in an oven at 130 ° C. and heat-treated for 2 minutes. Thereafter, UV irradiation (about 300 mJ / cm ² when converted to UV intensity) was performed on a conveyor type UV irradiation apparatus equipped with a high pressure mercury lamp (120 w) at a speed of 5 m / min. The thickness of the obtained cured film was about 100 nm.

  Thus, an optical article was obtained in which a high refractive index layer and a low refractive index layer (coating material) were provided in this order on the substrate. The obtained optical article was subjected to refractive index, light reflectance measurement, hardness evaluation, and fingerprint wiping evaluation. The results are shown in Table 1.

(Example 2)
Formic acid aqueous solution prepared in 40.6 g of methyltrimethoxysilane, 29.3 mg of trifluoropropyltrimethoxysilane, 134.7 g of hollow silica sol, 276.2 g of porous silica sol, and 1.0 N in the above [Preparation method of coating material] The experiment was performed in the same manner as in Example 1 except that the amount was changed to 23.4 g.
The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in this coating material was 42 parts by weight / 29 parts by weight / 29 parts by weight, The ratio of the curing agent to 100 parts by weight was 4 parts by weight.
The results are shown in Table 1. Good values were shown in all evaluations.

(Example 3)
Formic acid aqueous solution prepared in 48.3 g of methyltrimethoxysilane, 34.8 g of trifluoropropyltrimethoxysilane, 116.1 g of hollow silica sol, 238.1 g of porous silica sol, and 1.0 N in the above [Preparation method of coating material] The experiment was performed in the same manner as in Example 1 except that the amount was changed to 34.06 g.
The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in the coating material is 50 parts by weight / 25 parts by weight / 25 parts by weight, The ratio of the curing agent to 100 parts by weight was 4 parts by weight.
The results are shown in Table 1. Good values were shown in all evaluations.

(Comparative Example 1)
In the above [Method for preparing coating material], 48.3 g of methyltrimethoxysilane, 34.8 g of trifluoropropyltrimethoxysilane, 0 g of hollow silica sol, and 0 g of porous silica sol were used to form voids and non-porous silica sol (manufactured by Catalyst Kasei Chemical Industry). (OSCAL, average particle size 13 nm, solid content 30%) The experiment was conducted in the same manner as in Example 1 except that the weight was changed to 166.7 g.
In this coating material, the ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles was 50 parts by weight / 0 parts by weight / 0 parts by weight. 50 parts by weight of non-quality silica. The ratio of the curing agent to 100 parts by weight of the total was 4 parts by weight.
The results are shown in Table 1. The refractive index was 1.45, which was poor.

(Comparative Example 2)
In the above [Method for preparing coating material], 57.96 g of methyltrimethoxysilane, 41.76 g of trifluoropropyltrimethoxysilane, 33.34 g of formic acid aqueous solution prepared to 1.0 N, 0 g of hollow silica sol, and 381 g of porous silica sol The experiment was performed in the same manner as in Example 1 except for the change.
The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in the coating material is 60 parts by weight / 0 parts by weight / 40 parts by weight, The ratio of the curing agent to 100 parts by weight was 4 parts by weight.
The results are shown in Table 1. The refractive index was 1.42, which was poor.

(Comparative Example 3)
In the above [Method for preparing coating material], 57.96 g of methyltrimethoxysilane, 41.76 g of trifluoropropyltrimethoxysilane, 33.34 g of formic acid aqueous solution prepared to 1.0 N, 186.5 g of hollow silica sol, porous silica sol The experiment was performed in the same manner as in Example 1 except that the amount was changed to 0 g.
The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in the coating material is 60 parts by weight / 40 parts by weight / 0 parts by weight, The ratio of the curing agent to 100 parts by weight was 4 parts by weight.
The results are shown in Table 1. The refractive index was 1.366, which was poor.

(Comparative Example 4)
The experiment was performed in the same manner as in Example 1 except that the above [Method for preparing coating material] was changed to 0 g of hollow silica sol and 428.6 g of porous silica sol.
The ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles in the coating material is 55 parts by weight / 0 part by weight / 45 parts by weight, The ratio of the curing agent to 100 parts by weight was 4 parts by weight.
The results are shown in Table 1. The refractive index was 1.424, which was poor.

(Comparative Example 5)
In the above [Preparation Method of Coating Material], 40.6 g of methyltrimethoxysilane, 29.3 g of trifluoropropyltrimethoxysilane, 269.5 g of hollow silica sol, 0 g of porous silica sol, 23% formic acid aqueous solution prepared to 1.0N. The experiment was performed in the same manner as in Example 1 except that the amount was changed to 4 g.
In this coating material, the ratio of (A) compound having perfluoro group / (B) silica fine particles / (C) porous silica fine particles was 42 parts / 58 parts by weight / 0 parts by weight, and the total amount was 100. The ratio of the curing agent to parts by weight was 4 parts by weight.
The results are shown in Table 1. The coating film was whitened, and the refractive index and the reflectance could not be evaluated.

  According to the coating material of the present invention, since the surface hardness is high, the scratch resistance is excellent, and a coating film having a low refractive index can be formed, an optical article formed with this coating film on a substrate is a reflective material. Anti-reflection film, anti-reflection film, anti-reflection plate, optical filter, optical lens, display and other optical articles, more specifically, for example, CRT, LCD, PDP, EL, FED front plate and rear projection screen It is extremely useful in the optical field.

Claims (8)

  (A) a compound having a perfluoro group, (B) silica fine particles having voids in an average particle diameter of 40 to 100 nm, and (C) porous silica fine particles having an average particle diameter of 5 to 30 nm. The coating material whose refractive index of the film obtained after coating is 1.365 or less. The compound (A) having a perfluoro group is a polysiloxane obtained from an organosilicon compound represented by the following general formulas (1) and (2) and / or a hydrolyzate thereof and / or a condensate thereof. Item 4. The coating material according to Item 1.
R ¹ —Si (R ² ) _a X _3-a (1)
(In the formula, R ¹ is an organic group having fluorine having 3 to 12 carbon atoms, R ² is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group, and a is 0 or 1.)
R ³ b-SiR ⁴ cY _{4- (b + c)} (2)
(In the formula, R ³ and R ⁴ are each an alkyl group, alkenyl group, aryl group, or a hydrocarbon group having an epoxy group, a glycidoxy group, an amino group, a methacryloxy group, or a cyano group, and Y is a hydrolyzable group. And b and c are 0 or 1, and (b + c) is 1 or 2.)   The coating material according to claim 1 or 2, wherein the (B) silica fine particles are hollow silica having a core-shell structure.   The coating material according to any one of claims 1 to 3, wherein the porosity of the (C) porous silica fine particles is 20 to 90%.   The coating material according to claim 1, further comprising (D) a curing catalyst containing an aluminum chelate compound.   In a state where a part or all of the compound (A) having a perfluoro group is hydrolyzed, the (B) silica fine particles and / or (C) the porous silica fine particles are mixed to obtain one silanol group. The manufacturing method of the coating material of any one of Claims 1-5 which has the coating liquid preparation process which condenses a part.   An optical article obtained by laminating the coating material according to any one of claims 1 to 5 on at least one surface of a transparent substrate as a low refractive index layer. High refractive index layer surface of a transparent substrate with a coating provided with a high refractive index layer having a refractive index of 1.5 to 2.0 and a surface resistance of 1 × 10 ¹⁰ Ω / □ or less on at least one surface An optical article having antireflective properties, wherein the coating material according to any one of claims 1 to 5 is laminated.