JP2002265866A - Low-refractive index coating material and antireflection film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a single layer antireflection film of a low-refractive index, excellent in abrasion resistance and an antifouling property with a fingerprint, etc. SOLUTION: The low-refractive index coating material and the antireflection film are characterized by comprising a copolymer of a composition A composed either of an organosilicon compound represented by Si(OR)4 (R is a linear or branched alkyl) or a polymer of the compound and a composition B composed either of a perfluoropolyether group-containing silicon compound represented by Rf-(OC3 F6 )n -O-(CF2 )m -(CH2 )l -O-(CH2 )s -Si(OR)3 (Rf is a 1-16C linear or branched perfluoroalkyl; n is an integer of 1-50; m is an integer of 0-3; l is an integer of 0-3 and satisfies 6>=m+l>0; s is an integer of 0-6; and R is an linear or branched alkyl) or a polymer of the compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low refractive index coating agent and a display provided with the low refractive index coating agent on a transparent substrate (liquid crystal display, CRT display, projection display, plasma display, EL display, etc.). The present invention relates to an antireflection film applied to the surface of a display screen.

[0002]

2. Description of the Related Art Many displays are used in an environment where external light or the like is incident regardless of whether indoors or outdoors. The incident light such as external light is specularly reflected on the display surface or the like, and the reflected image is mixed with the display light to lower the display quality, making it difficult to view the display image. Especially in recent offices
With the shift to A, the frequency of using a computer has increased, and it has been a long time to use the computer. It is considered that the deterioration of the display quality due to the reflection image or the like causes a health disorder such as eye fatigue. Furthermore, in recent years, with the widespread use of outdoor life, opportunities for using various displays outdoors tend to increase more and more, and there is a demand for further improving display quality and clearly displaying display images.

As an example for satisfying these requirements, it has been known that a coating layer containing transparent fine particles is formed on the surface of a transparent plastic film substrate, and external light is irregularly reflected by an uneven surface.

Separately, a high refractive index layer and a low refractive index layer made of a metal oxide or the like are laminated on the surface of a transparent plastic film substrate, or a low refractive index layer made of an inorganic compound or an organic fluorine compound is formed on the surface. It is known that an antireflection film having an antireflection effect over a wide range of visible light formed of a single layer is used by bonding it to a display surface or the like.

[0005] An antireflection layer in which a high refractive index layer and a low refractive index layer made of the above metal compound or the like are laminated or a low refractive index layer made of an inorganic compound or an organic fluorine compound is formed as a single layer is generally used. , PVD (Physical Vapor)
Deposition (vacuum deposition, reactive deposition, ion beam assist, sputtering, ion plating, etc.), CVD (Chemical)
It is formed by a dry coating method such as a Vapor Deposition method. Such a dry coating method has disadvantages in that the size of the substrate is limited, and it is not suitable for continuous production, and the production cost is high.

[0006] Therefore, a wet coating method (dip coating method, spin coating method, flow coating method, spray coating method, roll coating method, gravure roll, etc.), which can be manufactured at a low cost because of its large area and continuous production, is possible. Coating method, air doctor coating method, blade coating method, wire doctor coating method, knife coating method, reverse coating method, transfer roll coating method, microgravure coating method, kiss coating method, cast coating method, slot orifice coating method, calendar coating Method, die coating method, etc.) has attracted attention.

As a means for obtaining a low refractive index layer by a wet coating method, a method using a material containing a fluorine element having a low refractive index and a method of providing a hole in the layer and lowering the refractive index by mixing air. They are roughly divided into Specific materials constituting the low-refractive-index layer by the above method include a fluorine-containing organic material, fine particles having a low refractive index, and the like, and it has been proposed to use these materials alone or in combination. For example, Japanese Patent Application Laid-Open No. Hei 2-19801 proposes using a fluorine-containing organic material. JP-A-6-230201 proposes to use a fluorine-containing organic material and low refractive index fine particles. JP-A-7-331115 proposes using a fluorine-containing organic material and an alkoxysilane. Japanese Patent Application Laid-Open No. Hei 8- 211202 proposes to use alkoxysilane and fine particles having a low refractive index.

[0008]

The low refractive index layer used as the outermost layer of the antireflection film needs to have not only a low refractive index but also not to be easily damaged by abrasion or the like. Also, when used by humans, fingerprints, sebum, sweat,
It is necessary to prevent the attachment of dirt such as cosmetics and to make it easy to wipe off even if attached.

However, the low refractive index layer in the prior art cannot satisfy all of the characteristics of refractive index, mechanical strength and antifouling property. If all of these properties are not satisfied, it cannot be practically used for an antireflection film having a single low refractive index layer.

The present invention has been made to solve the above-mentioned problems of the prior art, and has a very low refractive index, the surface of the low refractive index layer is hardly scratched by rubbing or the like, and the low refractive index layer is hardly damaged. No peeling, and fingerprints,
Prevents sebum, sweat, dirt such as cosmetics from attaching,
It is an object of the present invention to provide an antireflection film having a single low refractive index layer that can be easily wiped off even if it adheres.

[0011]

Means for Solving the Problems In order to solve the above problems, the invention according to claim 1 comprises an organic silicon compound represented by the following general formula (1) or a polymer of the organic silicon compound. A composition A, a perfluoropolyether group-containing silicon compound represented by the following general formula (2),
Alternatively, a low-refractive-index coating agent comprising a copolymer with the composition B comprising any of the polymers of the perfluoropolyether group-containing silicon compound.

Si (OR) ₄ ... (1) (where R is a linear or branched alkyl group)

Rf- (OC ₃ F ₆ ) _n -O- (CF ₂ ) _m- (CH ₂ ) ₁ -O- (CH ₂ ) _s -Si (OR) ₃ (2) (where, Rf is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms, n is an integer of 1 to 50, and m is 0 to 0)
An integer of 3, 1 is an integer of 0 to 3, s is an integer of 0 to 6, provided that 6 ≧ m + 1> 0, and R is a linear or branched alkyl group.

According to a second aspect of the present invention, in the low refractive index coating agent according to the first aspect, the mixing molar ratio of the composition A and the composition B is 50:50 to 99:
It is characterized by being 1.

According to a third aspect of the present invention, there is provided the low refractive index coating agent according to the first or second aspect, wherein the average particle diameter is 0.5.
It is characterized in that a hollow silica sol of up to 200 nm is added.

According to a fourth aspect of the present invention, in the low refractive index coating agent according to any one of the first to third aspects, the addition amount of the hollow silica sol is 5 to 95 wt%, and the refractive index thereof is 1.40. characterized in that it is a range of ～1.34.

According to a fifth aspect of the present invention, there is provided an antireflection film comprising a low refractive index layer provided by applying the low refractive index coating agent according to any one of the first to fourth aspects on a transparent substrate. It is.

According to a sixth aspect of the invention, in the antireflection film according to the fifth aspect, a hard coat layer is provided between the transparent substrate and the low refractive index layer.

According to a seventh aspect of the present invention, in the antireflection film according to the sixth aspect, the hard coat layer is made of a polymer containing a polyfunctional monomer containing a (meth) acryloyloxy group as a main component. It is characterized by.

The invention according to claim 8 is the antireflection film according to claim 6 or 7, wherein the surface of the hard coat layer on which the low refractive index layer is provided is surface-treated.

According to a ninth aspect of the present invention, in the antireflection film according to the eighth aspect, the surface treatment is an alkali treatment.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
FIG. 1 is a sectional view showing an example of the antireflection film of the present invention. As shown in the figure, an antireflection film 1 in which a hard coat layer 3 and a low refractive index layer 4 are formed on at least one surface of a transparent plastic film substrate 2.

Examples of the transparent plastic film substrate 2 include substrates made of various organic polymers. Usually, the substrate used as an optical member is transparent,
Polyolefins (polyethylene, polypropylene, etc.), polyesters (polyethylene terephthalate, polyethylene naphthalate, etc.), polyamides in view of optical properties such as refractive index and dispersion, and various physical properties such as impact resistance, heat resistance, and durability System (nylon-6, nylon-6
6), polystyrene, polyvinyl chloride, polyimide,
It is made of polyvinyl alcohol, ethylene vinyl alcohol, acryl, cellulose (triacetyl cellulose, diacetyl cellulose, cellophane, etc.), or a copolymer of these organic polymers.

Known organic additives such as antistatic agents, ultraviolet absorbers, plasticizers, lubricants, coloring agents, antioxidants, flame retardants, etc. are contained in the organic polymer constituting these transparent plastic film substrates. Those that have been used can also be used.

The transparent plastic film substrate may be a single layer or a laminate of a plurality of organic polymers. The thickness is not particularly limited, but is preferably 70 to 200 μm.

The hard coat layer 3 improves the hardness of the surface of the transparent plastic substrate, prevents scratches caused by a heavy load such as a pencil, and prevents cracks in the antireflection layer due to bending of the transparent plastic film substrate. Can be suppressed, and the mechanical strength of the antireflection film can be improved. The hard coat layer is composed of a polymer mainly composed of a polyfunctional monomer containing two or more (meth) acryloyloxy groups in one molecule. As the polyfunctional monomer,
1,4-butanediol di (meth) acrylate, 1,
6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, dipropylene glycol di (meth) ) Acrylate, 3-methylpentanediol di (meth) acrylate, diethylene glycol bis β-
(Meth) acryloyloxypropinate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tri (2-hydroxyethyl) Isocyanate di (meth) acrylate, pentaerythritol tetra (meth) acrylate, 2,3
-Bis (meth) acryloyloxyethyloxymethyl [2.2.1] heptane, poly1,2-butadienedi (meth) acrylate, 1,2-bis (meth) acryloyloxymethylhexane, nonaethylene glycol di (meth) ) Acrylate, tetradecane ethylene glycol di (meth) acrylate, 10-decanediol (meth) acrylate, 3,8-bis (meth) acryloyloxymethyltricyclo [5.2.10] decane, hydrogenated bisphenol A di (meth) ) Acrylate, 2,2
-Bis (4- (meth) acryloyloxydiethoxyphenyl) propane, 1,4-bis ((meth) acryloyloxymethyl) cyclohexane, hydroxypivalic acid ester neopentyl glycol di (meth) acrylate, bisphenol A diglycidyl ether di (Meth) acrylate, epoxy-modified bisphenol A di (meth) acrylate, and the like. As the polyfunctional monomer, only one kind may be used, or two or more kinds may be used in combination. If necessary, it can be copolymerized with a monofunctional monomer.

It is more preferable that the hard coat layer has a refractive index equal or similar to that of the transparent plastic film substrate. If the film thickness is 3 μm or more, sufficient strength is obtained, but a range of 5 to 7 μm is preferable in terms of transparency, coating accuracy and handling.

The hard coat layer has an average particle size of 0.01 to
3 μm inorganic or organic fine particles are mixed and dispersed. Alternatively, light diffusion treatment generally called anti-glare can be performed by making the surface shape uneven. These fine particles are not particularly limited as long as they are transparent,
Low refractive index materials are preferable, and silicon oxide and magnesium fluoride are preferable in terms of stability, heat resistance and the like. These hard coat layers may be applied in any manner as long as they can be applied uniformly.

Before applying the low refractive index coating agent of the present invention on the hard coat layer, it is necessary to perform a surface treatment. By performing the surface treatment, the adhesion between the hard coat layer and the low refractive index layer can be improved. The surface treatment of the hard coat layer includes a high-frequency discharge plasma method, an electron beam method, an ion beam method, an evaporation method, a sputtering method, an alkali treatment method, an acid treatment method, a corona treatment method,
Atmospheric pressure glow discharge plasma method can be used.
In particular, an alkali treatment method is effective. Examples of the aqueous alkali solution used for the alkali treatment include aqueous solutions of sodium hydroxide, potassium hydroxide and the like, and aqueous alkali solutions obtained by further adding various organic solvents such as alcohol thereto. The conditions of the alkali treatment are, for example, when an aqueous sodium hydroxide solution is used, it is preferable to use an aqueous solution having a concentration of 0.1 to 10N.
A concentration of ~ 2N is desirable. The temperature of the aqueous alkali solution is 0 to 100 ° C, preferably 20 to 80 ° C.
The time of the alkali treatment is 0.01 to 10 hours, preferably 0.1 to 1 hour.

The low refractive index coating agent of the present invention is a composition A comprising an organosilicon compound represented by the following general formula (1) or a polymer of the organosilicon compound.
And a copolymer of a perfluoropolyether group-containing silicon compound represented by the following general formula (2) and a composition B comprising a polymer of the perfluoropolyether group-containing silicon compound. Features.

Si (OR) ₄ (1)

Rf— (OC ₃ F ₆ ) _n —O— (CF ₂ ) _m — (CH ₂ ) ₁ —O— (CH ₂ ) _s —Si (OR) ₃ ・ ・ ・ ・ ・ （２）

In the general formula (1), R is linear or
An organic compound represented by the general formula (1), which is a branched alkyl group
As the silicon compound, Si (OCH_Three)_Four, Si (OC_Two
H_Five) _Four, Si (OC_ThreeH₇)_Four, Si [OCH (C
H_Three)_Two)]_Four, Si (OC_FourH₉)_FourEtc. can be exemplified.
May be used alone or in combination of two or more.

Next, the perfluoropolyether group-containing silicon compound represented by the general formula (2) will be described. In the general formula (2), Rf is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms.
_{3 -, C 2 F 5 -} , C 3 F 7 - is preferred. R is carbon number 1
5 is a linear or branched alkyl group,
CH ₃ and —OC ₂ H ₅ are preferred. N is an integer of 1 to 50; m is an integer of 0 to 3; l is an integer of 0 to 3;
An integer of 6, where 6 ≧ m + 1> 0.

A polymer is prepared using the organosilicon compound represented by the general formula (1) or the perfluoropolyether group-containing silicon compound represented by the general formula (2), or A method for producing a copolymer using the organosilicon compound represented by the formula (2) or a perfluoropolyether group-containing silicon compound represented by the general formula (2) or a polymer thereof is not limited. As a catalyst for producing by hydrolysis, known, hydrochloric acid, oxalic acid, nitric acid, acetic acid, hydrofluoric acid, formic acid, phosphoric acid, oxalic acid,
Ammonia, aluminum acetonate, dibutyltin laurate, tin octylate compounds, methanesulfonic acid, trichloromethanesulfonic acid, paratoluenesulfonic acid, trifluoroacetic acid, etc.
Alternatively, two or more kinds may be used in combination.

By adding a hollow silica sol to the above low refractive index coating agent, it is possible to lower the refractive index. Since the hollow silica sol contains air therein, its own refractive index is ordinary silica (refractive index = 1.
46) (refractive index = 1.34). Also, when this hollow silica sol is added to a low refractive index coating agent, the silica sol is hollow, so that the organic silicon compound as the matrix and the perfluoropolyether group-containing silicon compound are not immersed inside the silica sol. , The refractive index can be prevented from rising.

The average particle size of the hollow silica sol is 0.5 to 2
A value within the range of 00 nm is good. This average particle size is 200
When it is larger than nm, light is scattered by Rayleigh scattering on the surface of the low-refractive-index layer, looks whitish, and its transparency is reduced. If the average particle size is less than 0.5 nm, the hollow silica sol tends to aggregate.

The low refractive index coating agent is usually applied after being diluted in a volatile solvent. What is used as the diluting solvent is not particularly limited, but in consideration of the stability of the composition, wettability to the hard coat layer, volatility, and the like,
Alcohols such as methanol, ethanol, isopropanol, butanol and 2-methoxyethanol; ketones such as acetone, methyl ethyl ketone and methyl isobutyl; esters such as methyl acetate, ethyl acetate and butyl acetate; ethers such as diisopropyl ether; ethylene glycol Glycols such as propylene glycol, hexylene glycol, ethyl cellosolve, butyl cellosolve, ethyl carbitol, glycol ethers such as butyl carbitol, hexane, heptane, aliphatic hydrocarbons such as octane, halogenated hydrocarbons, benzene, Examples thereof include aromatic hydrocarbons such as toluene and xylene, N-methylpyrrolidone, dimethylformamide and the like.
Further, the solvent may be used not only as one kind but also as a mixture of two or more kinds.

The low refractive index coating agent can be prepared by a wet coating method (dip coating method, spin coating method, flow coating method, spray coating method, roll coating method, gravure roll coating method, air doctor coating method, plaid coating method, wire coating method). Doctor coating, knife coating, reverse coating, transfer roll coating, microgravure coating, kiss coating, cast coating,
It is coated on the hard coat layer which has been subjected to surface treatment by a slot orifice coating method, a calendar coating method, a die coating method, or the like. After coating, the solvent in the coating film is volatilized by heating and drying, and then heating, humidification,
The coating film is cured by irradiating ultraviolet rays, irradiating an electron beam, or the like.

The refractive index of the low-refractive-index layer formed using the low-refractive-index coating agent of the present invention is lower than those of the transparent plastic film substrate and the hard coat layer. Thickness (d) of this low refractive index layer
Is preferably nd = λ / 4, where n is the refractive index of the low refractive index layer.

[0041]

Embodiments of the present invention will be described below in detail, but the present invention is not limited to the embodiments.

Example 1 (Formation of Hard Coat Layer) Base of Transparent Plastic Film
As the material 2, a TAC film (80 μm in thickness) was used.
Also, dipentaerythritol hexaacrylate, and
And pentaerythritol tetraacrylate
A coating solution for a hard coat layer was prepared. This hard coat
TAC fill using microgravure method
120μm metal halide with a thickness of 5μm
The lamp was moved from a distance of 20 cm for 10 sec. Irradiate
Thereby, the hard coat layer 3 was formed. (Surface treatment) The TAC film having the hard coat layer formed thereon
1.5N NaOH aqueous solution heated to 50 ° C
Immersed for 2 minutes in an alkaline treatment, washed with water, and then
0.5wt% -H_TwoSO_FourImmerse in aqueous solution for 30 seconds at room temperature
It was neutralized, washed with water and dried. (Production of Low Refractive Index Layer) Si (OC_TwoH_Five95 mol of 4)
%, C_ThreeF₇-(OC_3F6)_{twenty four}-O- (CF_Two) _Two―C_TwoH_Four
-O-CH_TwoSi (OCH_Three)_ThreeAt 5 mol%,
Low refractive index coating using 1.0N-HCl as catalyst
An agent was prepared. Hard coat layer that has been subjected to the above surface treatment
Using the microgravure method on the formed TAC film
Coating solution with a thickness of 100 nm,
Forming a low refractive index layer 4 by drying at 1 ° C. for 1 minute
did.

Example 2 The formation of the hard coat layer and the surface treatment were the same as in Example 1. (Preparation of low refractive index layer) 95 mol of Si (OC ₂ H ₅ ) 4
_{%, C 3 F 7 - (} OC 3 F 6) 24 -O- (CF 2) 2 -C 2 H 4
The _{-O-CH 2 Si (OCH 3} ) 3 with respect to the matrix was mixed with 5 mol%, the hollow silica sol having an average particle diameter of 60nm was added 50 wt%, the low-refractive index coating agent using 1.0 N-HCl in the catalyst Was prepared. A coating solution having a thickness of 1 was applied on the TAC film on which the hard coat layer having been subjected to the surface treatment was formed by using a microgravure method.
A low refractive index layer was formed by coating at 00 nm and drying at 120 ° C. for 1 minute.

Example 3 The formation of the hard coat layer and the surface treatment were the same as in Example 1. (Production of Low Refractive Index Layer) Si (OC ₂ H ₅ ) ₄ (A) and C _{3
F 7 - (OC 3 F 6} ) 24 -O- (CF 2) 2 -C 2 H 4 -O-
The mixed mole% of CH ₂ Si (OCH ₃ ) ₃ (B) was
Hollow silica sol having an average particle size of 60 nm was added to three types of matrices of 0, 80:20, and 95: 5 in 10 watts.
Three types of low-refractive-index coating agents were prepared by adding 1.0% tN and using 1.0N-HCl as a catalyst. A low-refractive-index layer was formed by applying a film having a thickness of 100 nm on the TAC film substrate with a hard coat layer having been subjected to the alkali treatment prepared above using a microgravure method and drying at 120 ° C. for 1 minute. . Using a microgravure method, three types of low-refractive-index coating agents each having a thickness of 100 nm were applied to a TAC film on which a hard coat layer having been subjected to the same surface treatment as in Example 1 was formed, and dried at 120 ° C. for 1 minute. Was performed to form a low refractive index layer.

<Example 4> Formation of a hard coat layer, and
The surface treatment is the same as in the first embodiment. (Production of Low Refractive Index Layer) Si (OC_TwoH_Five)_Four95 mol
%, C_ThreeF₇-(OC_ThreeF₆)_{twenty four}-O- (CF_Two) _Two―C_TwoH_Four
-O-CH_TwoSi (OCH_Three)_ThreeWas mixed at 5 mol%
Hollow silica with an average particle size of 60 nm for the matrix
Four types with sol addition amount of 5, 10, 50, 75 wt%
And four kinds of low refraction using 1.0N-HCl as a catalyst
A coating agent was prepared. Same surface treatment as in Example 1.
On TAC film with hard coat layer
Four types of low refractive index coating using microgravure method
Coating agents each having a thickness of 100 nm,
After drying for a minute, a low refractive index layer was formed.

Comparative Example 1 The formation of the hard coat layer and the surface treatment were the same as in Example 1. (Production of Low Refractive Index Layer) Si (OC ₂ H ₅ ) ₄
1%, and a low refractive index coating agent using 1.0N-HCl as a catalyst was prepared. A low-refractive-index coating agent having a thickness of 100 nm was applied to the TAC film on which a hard coat layer having been subjected to the same surface treatment as in Example 1 was formed by a microgravure method, and dried at 120 ° C. for 1 minute. A low refractive index layer was formed.

In the above Examples and Comparative Examples, various physical property evaluation methods and evaluation results are shown below.

(Methods for evaluating various physical properties) (a) Optical properties (a) -1 Measurement of reflectance: After rubbing the film surface with sandpaper and applying a matte black paint, the wavelength was 550.
The reflectivity of one side at an incident angle of 5 nm was measured. (B) Antifouling property (b) -1 Contact angle measurement: Using a contact angle meter [CA-X: manufactured by Kyowa Interface Science Co., Ltd.], dry state (20 ° C-65).
% RH), a droplet having a diameter of 1.8 μl was formed at the needle tip, and this was brought into contact with the surface of the substrate (solid) to form a droplet. The contact angle is an angle formed by a tangent to the liquid surface at a point where the solid and the liquid come into contact with each other, and is defined as an angle including the liquid. Distilled water was used as the liquid. (B) -2 Wipeability of oily pen: Cellulose nonwoven fabric [Bencott M-3:
(Manufactured by Asahi Kasei Corporation)], and the ease of removal was visually determined. The criteria are shown below. ：: The oil pen can be completely wiped off. Δ: Wipe marks of oily pen remain. ×: The oily pen cannot be wiped off. (B) -3 Wiping property of fingerprint: The fingerprint adhering to the substrate surface was wiped off with a cellulose nonwoven fabric (Bencott M-3: manufactured by Asahi Kasei Corporation), and the ease of removal was visually determined. The criteria are shown below. ：: The fingerprint can be completely wiped off. Δ: Fingerprint wiping remains. ×: The trace of wiping of the fingerprint spread and could not be wiped off. (C) Mechanical strength (c) -1 Scratch resistance: The surface of the base material was rubbed 20 times with steel wool (Bonstar # 0000: manufactured by Nippon Steel Wool Co., Ltd.) at 250 g / cm2 to visually determine the presence or absence of scratches. (Steel wool test). The criteria are shown below. ：: No scratch can be confirmed. Δ: Several scratches can be confirmed. ×: Many scratches can be confirmed. (C) -2 Adhesion: After cutting 100 points of 1 mm square on the surface of the base material, the adhesive cellophane tape [Nichiban Industrial Co., Ltd. 2
[4 mm wide cellophane tape] was visually checked for the presence or absence of peeling (cross cut tape peel test).

(Results of Evaluation of Various Physical Properties)
2, the evaluation results of Comparative Example 1, Table 2 shows the evaluation results of Example 3, and Table 3 shows the evaluation results of Example 4.

[0050]

[Table 1]

[0051]

[Table 2]

[0052]

[Table 3]

[0053]

According to the present invention, a hard coat layer made of a polymer containing a polyfunctional monomer as a main component is provided on at least one surface of a transparent plastic film substrate, and the surface of the hard coat layer is subjected to an alkali treatment or the like. After processing,
Since it has a low-refractive-index layer coated with a low-refractive-index coating agent composed of an organosilicon compound and hollow silica sol, the refractive index is extremely low, and the surface of the low-refractive index layer is scratched due to scratching or the like. It is difficult to peel off the low-refractive index layer, and it is possible to prevent fingerprints, sebum, sweat, cosmetics, etc. from adhering to the surface of the low-refractive index layer, and to easily wipe off even if it adheres. An antireflection film having a single low refractive index layer can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of the antireflection film of the present invention.

FIG. 2 is a sectional view of a low refractive index layer of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Anti-reflection film 2 ... Substrate 3 ... Hard coat layer 4 ... Low refractive index layer 5 ... Matrix 6 ... Hollow silica sol

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/72 G02B 1/10 Z F-term (Reference) 2K009 AA02 AA15 BB28 CC09 CC24 CC42 DD02 4J038 DL031 DL072 HA446 JC32 KA06 KA21 NA19 PB03 PB08 PC08 5C058 AA01 BA08 BA30 DA01

Claims (9)

[Claims] 1. A composition A comprising an organosilicon compound represented by the following general formula (1) or a polymer of this organosilicon compound, and a perfluoropolyether group represented by the following general formula (2): A low-refractive-index coating agent comprising a copolymer with a composition B comprising a silicon compound containing the compound or a polymer of the silicon compound containing a perfluoropolyether group. Si (OR) ₄ (1) (where R is a linear or branched alkyl group) Rf- (OC ₃ F ₆ ) _n -O- (CF ₂ ) _m- (CH _{2 ) l -O- (CH 2) s} -S i (OR) 3 (2) (where, Rf is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms, n is an integer of 1 to 50, and m is 0 to 0)
An integer of 3, 1 is an integer of 0 to 3, s is an integer of 0 to 6, provided that 6 ≧ m + 1> 0, and R is a linear or branched alkyl group. 2. The low refractive index coating agent according to claim 1, wherein the mixing molar ratio of the composition A and the composition B is 50:50 to 99: 1 in terms of mol%. Low refractive index coating agent. 3. The low refractive index coating agent according to claim 1, wherein a hollow silica sol having an average particle size of 0.5 to 200 nm is added to said low refractive index coating agent. 4. The addition amount of said hollow silica sol is 5 to 95 watts.
The low refractive index coating agent according to any one of claims 1 to 3, wherein the coating agent has a refractive index of 1.40 to 1.34. 5. An anti-reflection film comprising a low refractive index layer formed by applying the low refractive index coating agent according to claim 1 on a transparent substrate. 6. The anti-reflection film according to claim 5, wherein a hard coat layer is provided between the transparent substrate and the low refractive index layer. 7. The anti-reflection film according to claim 6, wherein said hard coat layer is made of a polymer mainly composed of a polyfunctional monomer having a (meth) acryloyloxy group. 8. The antireflection film according to claim 6, wherein a surface of the hard coat layer on which the low refractive index layer is provided is surface-treated. 9. The antireflection film according to claim 8, wherein said surface treatment is an alkali treatment.