JP2001026737A - Coating composition for antireflection coating and antireflection article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating composition capable of forming a coating film having excellent abrasion resistance on the surface of an article having large surface area by including a fluorine-containing resin, a specific polymerizable silicon compound, a polymerization initiator and an organic solvent. SOLUTION: The objective composition is produced by dissolving (A) a fluorine-containing resin (e.g. fluoroethylene polymer), (B) a polymerizable silicon compound of formula I (R1 and R2 are each a polymerizable functional group; R3 is methyl or the like; 1<n<20) or formula II (R4 is a polymerizable functional group; R5 is methyl or the like; x>=2; 1<y/x<9) and (C) a polymerization initiator (e.g. sodium methyldithiocarbamate sulfide) in (D) an organic solvent (e.g. toluene). The amount of the component B is preferably 10-100 pts.wt. based on 100 pts.wt. of the component A and that of the component C is preferably 0.1-10 wt.% based on the solid component in the composition. The amount of the component D is adjusted to give a solution having a solid concentration of 0.5-30 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antireflection coating composition and an antireflection treated article for performing an antireflection treatment on a large area article such as a large display.

[0002]

2. Description of the Related Art Heretofore, as a method for performing antireflection treatment on a large-area article such as a large-sized display, there has been known a method of thinly coating the surface of an article to be treated with a composition containing a fluorine-containing resin having a low refractive index. ing.

In this method, it is desirable to crosslink and cure the coating film in order to impart practical wear resistance and chemical resistance. For example, as described in JP-A-8-100136 and JP-A-8-48935, a coating film is formed by means of light irradiation or the like using a compound having a polymerizable ethylenically unsaturated group. Crosslinking and curing have been attempted.

However, since the above curing reaction proceeds by a radical mechanism, the curing is hindered by oxygen in the air, so that the curing tends to be insufficient. Since the antireflection coating film generally forms a very thin coating film having a thickness of about の of the wavelength of light, the specific surface area is large.
In particular, the influence of oxygen on curing inhibition is great. If the curing is insufficient, there is a problem that the wear resistance of the antireflection coating film is reduced.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional problems, and is intended to provide an anti-reflection coating having excellent wear resistance on the surface of a large-area article. An object of the present invention is to provide an antireflection coating composition for forming a coating and an antireflection treated article.

[0006]

Means for Solving the Problems The invention according to claim 1 of the present application (Invention 1) comprises a fluorine-containing resin, a silicon compound represented by the following general formulas (1) and (2), A coating composition for anti-reflection coating, comprising: an agent and an organic solvent.

[0007]

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[0008]

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The invention described in claim 2 of the present application (Invention 2)
Is a coating composition for antireflection coating according to invention 1, wherein the fluorine-containing resin has a fluorine content of 60% by weight or more.

The invention described in claim 3 of the present application (the present invention 3)
Is a compound in which the polymerization initiator generates a radical by light or heat, and wherein the polymerizable functional groups R1, R2, and R4 in the polymerizable silicon compound include a (meth) acryloyl group. Or the coating composition for anti-reflection coating according to 2.

The invention described in claim 4 of the present application (Invention 4)
Is a compound in which a polymerization initiator generates a cation by light or heat, and wherein the polymerizable functional groups R1, R2, and R4 in the polymerizable silicon compound include an epoxy group or an oxetane group. Or the coating composition for anti-reflection coating according to 2.

The invention according to claim 5 of the present application (the present invention 5)
Is an antireflection-treated article having a cured coating film of the coating composition for antireflection coating according to any one of inventions 1 to 4 formed on the surface, wherein the thickness of the cured coating film is 0.
An antireflection treated article characterized by having a thickness of 5 μm or less.

(Fluorine-Containing Resin) The fluorine-containing resin used in the present invention is selected in consideration of the refractive index, transparency, and solubility in a solvent. That is, generally, the optimum value of the refractive index of the antireflection film is in the range of 1.20 to 1.30, and the refractive index of the fluorine-containing resin does not fall below 1.3 even with a resin having a high fluorine content. The lower the rate, the better. Generally, as the fluorine content increases, the refractive index decreases,
The fluorine-containing resin in the present invention desirably has a fluorine content of 60% by weight or more because the antireflection effect is enhanced.

The antireflection-treated article of the present invention is required to have good transparency since it is arranged on the surface of a display or the like. Factors that hinder the transparency include light absorption and light scattering. However, since the antireflection coating film is formed to be extremely thin, the influence of the former is relatively small and the latter is problematic. If the compatibility between the fluorine-containing resin and other additives is poor, or if the crystallinity of the fluorine-containing resin itself is high, light scattering is likely to occur and transparency is deteriorated. Therefore,
A resin having an appropriate branched structure and good solubility is preferable.

Examples of the fluorine-containing resin include fluoroethylene, difluoroethylene, vinylidene fluoride, trifluoroethylene, tetrafluoroethylene,
Chlorotrifluoroethylene, 1,2-dichloro-1,
2-difluoroethylene, 2-bromo-3,3,3-trifluoropropylene, 3-bromo-3,3-difluoropropylene, 3,3,3-trifluoropropylene,
Fluorine-containing resins which are polymers or copolymers of 1,1,2-trichloro-3,3,3-trifluoropropylene, hexafluoropropylene, α-trifluoromethacrylic acid and the like can be mentioned.

(Polymerizable Silicon Compound) As the polymerizable silicon compound used in the present invention, those represented by the following general formula (1) or (2) are used. In the formula (1),-(Si) in the polymerizable silicon compound
-O) If the chain length of n- is too long, the crosslinking density does not increase, so that 1 <n <20 is preferable.

In the formula (2), the number x of the polymerizable functional groups in one molecule is preferably two or more. This is because if the number of polymerizable functional groups is one in one molecule, there is a high possibility that they remain without being involved in crosslinking. On the other hand, if the ratio of x to the number y of the non-polymerizable chain units is too small, the crosslink density becomes low, and strong film properties cannot be obtained. On the other hand, if the ratio is too large, an excess of the polymerizable functional unit tends to remain unreacted, so that it is not preferable, and a preferable ratio is 1 <y / x <9.

[0018]

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[0019]

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By using the above polymerizable silicon compound, a slipping effect is given to the antireflection coating film, and the abrasion resistance is improved. Simply mixing a non-polymerizable silicon compound is not sufficient in the strength of the antireflection film, so that a practical effect cannot be obtained. In order to obtain practically sufficient hardness, a silicon compound having a polymerizable functional group is used. As the polymerizable functional groups R1, R2, and R4, (meth) acryloyl groups that undergo addition polymerization by a radical mechanism are preferable. As the other polymerizable functional group, an epoxy group and an oxetane group polymerized by a cationic mechanism are still more preferable.
Polymerization by the cationic mechanism has the advantage that polymerization is not inhibited by oxygen.

The amount of the polymerizable silicon compound is as follows:
The amount is preferably 10 to 100 parts by weight based on 100 parts by weight of the fluorine compound. If the amount is less than 10 parts by weight, the obtained antireflection coating film does not have a sufficient sliding effect, and if it exceeds 100 parts by weight, the refractive index of the obtained antireflection coating film becomes too high, and the antireflection performance Tends to decrease. However, this is not the case when the refractive index of the polymerizable silicon compound itself is sufficiently low, and a good anti-reflection effect can be obtained even when used in excess of 100 parts by weight.

In the present invention, a polymerizable silicon compound and another polymerizable compound may be used in combination. Also in this case, the total amount of the polymerizable silicon compound and other polymerizable compounds is 10 to 100 parts by weight based on 100 parts by weight of the fluorine-containing resin.
It is preferably in the range of parts by weight.

When the functional group of the polymerizable silicon compound is radically polymerizable, the other polymerizable compound which can be preferably used in combination is, for example, a polyfunctional (meth) acrylate compound. The polyfunctional (meth) acrylate compound has at least two or more (meth) acryloyl groups in the molecule, and includes, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di ( (Meth) acrylate, tetraethylene glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate,
Tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, nonapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 2,2
-Bis [4-acryloxydiethoxyphenyl] propane, 2,2-bis [4-methacryloxydiethoxyphenyl] propane, 3-phenoxy-2-propanoyl acrylate, 1,6-bis (3-acryloxy-2 Bifunctional (meth) acrylates such as -hydroxypropyl) -hexyl ether; pentaerythritol tri (meth)
Acrylate, trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate,
Trifunctional (meth) acrylates such as tris- (2-hydroxyethyl) -isocyanurate (meth) acrylate; pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate And (4) functional (meth) acrylates such as acrylates.

When the functional group of the polymerizable silicon compound is cationically polymerizable, other polymerizable compounds that can be preferably used in combination include a polyfunctional epoxy compound. The polyfunctional epoxy compound is a compound having two or more epoxy groups in a molecule. For example, an alicyclic epoxy compound represented by the following chemical formula is preferably used.

[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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In addition to the above alicyclic epoxy compounds, polyglycidyl ether which is a reaction product of polyphenol such as bisphenol A, bisphenol F, and novolak resin with epichlorohydrin; ethylene glycol, propylene glycol, trimethylolpropane, pentaerythritol Polyglycidyl ether, which is a reaction product of a polyhydric alcohol such as the above and epichlorohydrin, is also preferably used.

(Polymerization Initiator) As the polymerization initiator in the present invention, those which are activated by light or heat to generate radicals or cations are used.

Examples of the polymerization initiator which is activated by ultraviolet rays to generate radicals include sulfides such as sodium methyldithiocarbamate sulfide, tetramethylthiuram monosulfide, diphenyl monosulfide, dibenzothiazoyl monosulfide and disulfide; Thioxanthone derivatives such as thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone and 2,4-diethylthioxanthone; (di) azo compounds such as hydrazone, azobisisobutyronitrile, benzenediazonium; benzoin, benzoin methyl ether, benzoin ethyl Ether, benzophenone, dimethylaminobenzophenone, Michler's ketone,
Benzylanthraquinone, t-butylanthraquinone,
Aromatic carbonyl compounds such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-aminoanthraquinone and 2-chloroanthraquinone; 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy- α, α'-dimethylacetophenone, 2,2-diethoxyacetophenone, 2,2
Acetophenone derivatives such as dimethoxyacetophenone; dialkylaminobenzoic esters such as methyl 2-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, butyl 4-dimethylaminobenzoate and isopropyl 4-diethylaminobenzoate; benzoyl peroxide Peroxides such as, di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide; acridine derivatives such as 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine, benzacridine; 9,10-dimethylbenzphenazine, 9-methylbenzphenazine,
Phenazine derivatives such as 10-methoxybenzphenazine; quinoxaline derivatives such as 6,4 ', 4 "-trimethoxy-2,3-diphenylquinoxaline; 2,4,5-
Triphenylimidazoyl dimer; acylated phosphorus compounds such as acylphosphine oxide and acylphosphonate.

Examples of the polymerization initiator that generates a radical upon activation with visible light include 2-nitrofluorene,
2,4,6-triphenylbrillium boron tetrafluoride salt,
2,4,6-tris (trichloromethyl) -1,3,5
-Triazine, 3,3'-carbonylbiscoumarin, thiomichler ketone and the like.

In order to prevent poor curing due to oxygen inhibition of the photoradical polymerization initiator, an amine compound may be added. Such amine compounds are not particularly limited as long as they are nonvolatile compounds such as aliphatic amines and aromatic amines. For example, triethanolamine, methyldiethanolamine and the like are used, and the dialkylaminobenzoic acid ester is further used. A photopolymerization initiator having an amino group, such as Michler's ketone, can also be used as the amine compound.

Examples of the polymerization initiator which is activated by heat to generate a radical include, for example, azobisisobutyronitrile, azobiscyclohexanecarbonitrile,
Azo compounds such as 2,2-azobis (2,4-dimethylvaleronitrile) and 2,2-azobis (4-methoxy-2,4-dimethylvaleronitrile), benzoyl peroxide, t-butyl peroxide, t- Peroxides such as butyl hydroperoxide, cumyl peroxide, acetyl peroxide, lauryl peroxide and the like can be mentioned.

In the present invention, the polymerization initiator which is activated by light to generate a cation includes aromatic diazonium salts, aromatic iodonium salts, aromatic sulfonium salts, pyridinium salts, iron-allene complex compounds, aluminum complex-silanols. And the like.

Examples of the polymerization initiator which is activated by heat to generate a cation include an iodonium salt, a sulfonium salt, a diazonium salt and the like.

The amount of the polymerization initiator is from 0.1 to 10% by weight based on the so-called solid content of the whole composition excluding the organic solvent.
Is desirable. If the content is 0.1% by weight or less, a sufficient curing reaction does not occur, and if the content is 10% by weight or more, physical properties of a cured product are deteriorated.

(Organic solvent) Examples of the organic solvent used in the present invention include aromatic hydrocarbons such as toluene and xylene; ketones such as methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate; General-purpose organic solvents widely used industrially, such as ethers such as monoethyl ether, can be used.

The amount of the organic solvent is preferably determined depending on the coating method, but it is generally preferable to dilute the organic solvent so that the solid content is in the range of 0.5 to 30% by weight. The anti-reflection coating film must be formed as extremely thin as 0.5 μm or less and without thickness unevenness. For that purpose, it is diluted with a large amount of a solvent and applied to a thickness several times to several tens times the predetermined thickness. This is because it is practical to remove the solvent and then adjust the nonvolatile content to a predetermined thickness.

The thickness of the cured film of the composition is 0.5 μm.
m or less, and it is desirable to adjust the thickness to about 程度 of the wavelength to be antireflective. If the thickness is 0.5 μm or more, the interference effect is reduced, the reflectance is increased, and the practical antireflection effect is reduced.

[0043]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 [Preparation of antireflection coating] 100 parts by weight of a fluorine-containing resin (trade name "Daiel G-501" manufactured by Daikin Industries, fluorine content 68% by weight) and the following formula (3) 20 parts by weight of a polymerizable silicon compound shown in Table 1 and 30 parts by weight of a radical polymerizable compound [a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (trade name "Kayarad DPHA", manufactured by Nippon Kayaku Co., Ltd.)] 1 part by weight of a radical polymerization initiator (manufactured by Nippon Kayaku Co., Ltd., trade name "Kayacure DETX") and a photo-radical polymerization initiator (manufactured by Nippon Kayaku Co., Ltd., trade name "Kayacure EP")
A ") 1 part by weight of methyl isobutyl ketone 4000
It was dissolved in parts by weight to obtain a coating for antireflection coating.

[0045]

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[Preparation of Anti-Reflection Treated Article] Thickness 100 μm
m on a treated substrate consisting of a polyethylene terephthalate (hereinafter abbreviated as “PET”) film using a “microgravure coater” manufactured by Yasui Seiki Co., Ltd. the coating is .1Myuemu, ultraviolet ultra-high pressure mercury lamp to cure the 500 mJ / cm ² irradiated to the coating film, to obtain a PET film with an antireflection treatment. The obtained antireflection-treated PET film is
As shown in FIG. 1, an antireflection-treated article was obtained by attaching the antireflection layers to both sides of a transparent acrylic plate so as to face outward.

[Evaluation of Antireflection Performance] The reflection spectrum of the surface of the antireflection treated article was measured using a spectrophotometer “UV-3100” manufactured by Shimadzu Corporation. The rate is 1.5
%Met. When this antireflection-treated article was placed on the front of a large display, a good image without reflection was observed.

[Evaluation of abrasion resistance] A commercially available cleaning cloth was applied on the surface of the antireflection-treated article.
When a load of 5 g / cm ² was applied and wiping was performed 300 times in a stroke of 5 cm at a speed of 1 reciprocation / second, no scratch was generated, and a streak was formed only after 400 reciprocations.

Example 2 An antireflection-treated article was obtained in the same manner as in Example 1 except that a polymerizable silicon compound represented by the following formula (4) was used as the polymerizable silicon compound.

[0050]

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[Evaluation of antireflection performance] The reflection spectrum of the surface of the antireflection treated article was measured using a spectrophotometer “UV-3100” manufactured by Shimadzu Corporation. The rate is 1.5
%Met. When this antireflection-treated article was placed on the front of a large display, a good image without reflection was observed.

[Evaluation of abrasion resistance] A commercially available cleaning cloth was applied on the surface of the antireflection-treated article.
After applying a load of g / cm ² and wiping 400 strokes at a speed of 1 reciprocation / sec with a stroke of 5 cm, no scratches were generated, and streaky scratches were formed only after 500 reciprocations.

Example 3 [Preparation of antireflection coating] 100 parts by weight of a fluorine-containing resin (trade name "Daiel G-501", manufactured by Daikin Industries, fluorine content 68% by weight) and the following formula (5) 20 parts by weight of a polymerizable silicon compound represented by the following formula, 30 parts by weight of a cationic polymerizable compound represented by the following formula (6) (trade name “Eporide GT-403”, manufactured by Daicel Chemical Industries, Ltd.), and the following formula (7) 3 parts by weight of a photocationic polymerization initiator (trade name "SP-170" manufactured by Asahi Denka Co., Ltd.) was dissolved in 4000 parts by weight of methyl isobutyl ketone to obtain an antireflection coating.

[0054]

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[0055]

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[0056]

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[Preparation of anti-reflection treated article] An anti-reflection treated article was obtained in the same manner as in Example 1 using the obtained anti-reflection coating. When the reflection spectrum of the surface of the antireflection treated article was measured, the bottom of the spectrum was 570.
nm and its reflectivity was 1.4%. When this antireflection-treated article was placed on the front of a large display, a good image without reflection was observed.

[Evaluation of Abrasion Resistance] The antireflection treated article was evaluated for the abrasion resistance performance in the same manner as in Example 1. As a result, there was no scratch after wiping 500 reciprocations. Scratched.

Example 4 An antireflection-treated article was obtained in the same manner as in Example 3, except that a polymerizable silicon compound represented by the following formula (8) was used as the polymerizable silicon compound.

[0060]

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(Adjustment of Anti-Reflection Treated Article) When the reflection spectrum of this anti-reflection treated article was measured, the bottom of the spectrum was at 570 nm, and the reflectance was 1.4.
%Met. When this antireflection-treated article was placed on the entire surface of a large-sized display, a favorable screen without reflection was observed.

[Evaluation of Abrasion Resistance] The anti-reflection treated article was evaluated for the abrasion resistance performance in the same manner as in Example 1. As a result, no damage was found in wiping 600 reciprocations. Scratched.

Comparative Example An antireflection-treated article was obtained in the same manner as in Example 1, except that the silicon compound was removed from the composition of Example 1 and the amount of the radical polymerizable compound was increased to 50 parts by weight. When the obtained antireflection-treated article was evaluated for abrasion resistance in the same manner as in Example 1, the article was scratched after 100 reciprocations of wiping.

[0064]

The coating composition for an antireflection coating of the invention 1 comprises:
Since it is made of a fluorine-containing resin, a silicon compound represented by the following general formula (1) or (2), a polymerization initiator, and an organic solvent, the anti-reflection film surface has increased slipperiness, and is subjected to abrasion and wiping stress. Are dispersed to increase wear resistance.

[0065]

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[0066]

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Further, in the invention 2, since the fluorine-containing resin has a fluorine content of 60% by weight or more, the refractive index is reduced and the antireflection effect is enhanced.

When the polymerizable functional groups R1, R2 and R4 in the polymerizable silicon compound contain a (meth) acryloyl group as in the invention 3, the polymerization initiator generates radicals by light or heat. Cross-linking and curing can be conveniently performed only by irradiating an activation energy beam with the polymerization initiator.

When the polymerizable functional groups R1, R2 and R4 in the polymerizable silicon compound contain an epoxy group or an oxetane group as in the invention 4, a polymerization initiator which generates cations by light or heat is used. Cation polymerization to prevent polymerization inhibition by oxygen.

The antireflection-treated article of Invention 5 is an antireflection-treated article having a cured coating film of the coating composition for antireflection coating formed on the surface thereof, wherein the thickness of the cured coating film is 0.5 μm or less. And a fluorine resin having a fluorine content of 60% or more is blended, so that the antireflection performance is good, and since the polymerizable silicon compound imparts slipperiness, it has high abrasion resistance.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining the structure of an antireflection-treated article coated with an antireflection coating film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anti-reflection coating film 2 PET film 3 Adhesive 4 Transparent acrylic plate

Continued on front page F-term (reference) 4J038 CD091 CD101 CD111 CD121 CD131 CG141 CH051 CH061 CH191 CH251 CL001 DB031 DB051 DB261 DL051 DL101 FA211 FA271 GA02 GA07 GA15 JA03 JA07 JA26 JA32 JA55 JA66 JA73 JB01 JB16 JB19 JB21 JB23 JBJ JB30 JC07 JC18 JC22 JC37 JC38 KA03 KA06 MA07 MA09 NA19 PA17

Claims (5)

[Claims] 1. An anti-reflection coating composition comprising a fluorine-containing resin, a polymerizable silicon compound represented by the following general formula (1) or (2), a polymerization initiator, and an organic solvent. Composition. Embedded image Embedded image 2. The coating composition for antireflection coating according to claim 1, wherein the fluorine-containing resin has a fluorine content of 60% by weight or more. 3. The polymerization initiator is a compound that generates a radical by light or heat, and the polymerizable functional groups R1, R2, and R4 in the polymerizable silicon compound include a (meth) acryloyl group. The coating composition for antireflection coating according to claim 1 or 2. 4. The method according to claim 1, wherein the polymerization initiator is a compound that generates cations by light or heat, and the polymerizable functional groups R1, R2, and R4 in the polymerizable silicon compound include an epoxy group or an oxetane group. The coating composition for antireflection coating according to claim 1 or 2. 5. An antireflection-treated article having a cured coating film of the coating composition for antireflection coating according to claim 1 formed on a surface thereof, wherein the cured coating is provided. An antireflection-treated article having a film thickness of 0.5 μm or less.