JP4893539B2 - Article having antiglare layer and method for producing the same - Google Patents

Description

  The present invention relates to an article having an antiglare layer and a method for producing the same.

In various image display devices (liquid crystal display (hereinafter referred to as LCD), plasma display (hereinafter referred to as PDP), etc.), external light such as indoor lighting (fluorescent lamps, etc.) and sunlight is displayed on the display surface. When the image is reflected in the image, the visibility decreases due to the reflected image.
As processing for suppressing the reflection of external light, the following antiglare (hereinafter referred to as AG) processing or low reflection (hereinafter referred to as AR) processing is known.
AG processing: processing that blurs the reflected image by forming irregularities on the display surface and diffusing and reflecting external light.
AR processing: processing for suppressing reflection of external light itself by forming an AR layer made of a combination of a transparent low refractive index material and a transparent high refractive index material on the display surface.

The AG process and the AR process have the following advantages and disadvantages, respectively.
Advantages of AG processing: Since the external light is diffusely reflected, the AG effect is exhibited regardless of the incident angle of the external light or the position of the person viewing the screen.
Disadvantages of AG processing: Image resolution decreases due to unevenness. The decrease in resolution increases as the distance between the display element and the AG processing surface increases. Moreover, haze increases due to irregular reflection due to unevenness, and the contrast of the image decreases.

Advantages of AR treatment: Since unevenness is not formed, there is no reduction in resolution or contrast due to haze.
Disadvantages of AR processing: Since the AR layer is designed based on the optical path length due to the normal incidence angle, the optical path length may deviate from the design depending on the incident angle of external light or the position of the person viewing the screen. Increases and the AR effect is impaired.

Since AG processing is more advantageous in terms of suppressing reflection of external light, AG processing can be directly performed on the polarizing film on the outermost layer of the display element, and the distance between the display element and the AG processing surface is short. In the LCD, AG processing is mainly adopted.
On the other hand, in a PDP in which a protective plate is provided with a gap in front of the display element, when the AG process is performed, it is necessary to perform the AG process on the protective plate. It drops significantly. Therefore, AR processing must be adopted in the PDP.

As articles having an AG layer or an AR layer containing particles, the following have been proposed.
(1) A film having an AG layer containing particles (Patent Documents 1 to 3).
(2) A base material having an AR layer containing hollow SiO ₂ fine particles (Patent Document 4).

However, the AG layer of (1) has a large haze because it is necessary to use particles having a large particle diameter in order to form irregularities on the surface.
The AR layer (2) has a smooth surface for the following reasons (i) and (ii), and therefore cannot provide an AG effect.
(I) Since the AR layer is designed on the basis of the optical path length due to the normal incidence angle, if the surface is uneven, the thickness of the AR layer becomes non-uniform, making it difficult to design the AR layer.
(Ii) The hollow SiO ₂ fine particles have a small particle diameter, and if the hollow SiO ₂ fine particles are simply included, the surface has no effective unevenness on the AG.
JP 2001-281405 A JP 2001-305314 A JP 2007-047722 A JP 2001-233611 A

  The present invention provides an article having an AG layer that has a good AG effect, has a low resolution, and has a sufficiently small haze, and a method for producing the same.

The article of the present invention comprises a base material, the refractive index is 1.45 or less, and surface roughness have a AG layer is 0.04～0.17Myuemu, the AG layer, the hollow fine SiO ₂ particles wherein the average agglomerated particle size of the hollow fine SiO ₂ particles is characterized 5~300nm der Rukoto.
The content of the hollow SiO ₂ fine particles is preferably 1 to 70% by mass in the AG layer (100% by mass).

The haze of the article of the present invention is preferably less than 6.5%.
The glossiness of the AG layer is preferably 60% or less.
In the method for producing an article of the present invention, the AG layer is formed by applying a coating solution containing a material capable of forming a coating film having a refractive index of 1.45 or less onto the substrate by a spray method. Features.

The article of the present invention has a good AG effect, a small decrease in resolution, and a sufficiently low haze.
According to the method for producing an article of the present invention, it is possible to produce an article having an AG layer that has a good AG effect, has little reduction in resolution, and has a sufficiently small haze.

<Article>
The article of the present invention is an article having a base material and an AG layer provided on the base material. The AG layer may be provided only on one side of the base material, or may be provided on both sides of the base material.
Examples of the article include various image display devices (LCD, PDP, etc.), filters or protective plates for image display devices, and cover glasses for solar cells.
The article of the present invention may have an alkali barrier layer, a colored layer, an antistatic layer and the like in addition to the AG layer.

The haze of the article is less than 6.5%, preferably 4% or less. If the haze of the article is less than 6.5%, the reduction in image contrast can be sufficiently suppressed. The lower the haze of the article, the better.
The haze of the article is measured using a commercially available haze meter according to JIS K7105 (1981).

(Base material)
Examples of the material for the substrate include glass and plastic.
Examples of the glass include soda lime glass, alkali-free glass, borosilicate glass, and quartz glass.
Examples of the plastic include polycarbonate, polyethylene terephthalate, and triacetyl cellulose. The plastic substrate may be subjected to primer treatment with a silane coupling material or the like from the viewpoint of adhesion to the AG layer.
As a base material, the shape, such as plate shape, film shape, and spherical shape, is not ask | required.

(AG layer)
The surface roughness of the AG layer is 0.04 to 0.17 μm, preferably 0.04 to 0.14 μm, and more preferably 0.04 to 0.1 μm. When the surface roughness of the AG layer is 0.04 μm or more, the glossiness is sufficiently suppressed, the reflected image is unclear, and the AG effect is sufficiently exhibited. When the surface roughness of the AG layer is 0.17 μm or less, the resolution is hardly lowered and the haze is sufficiently small.
The surface roughness of the AG layer is an arithmetic average roughness Ra defined in JIS B0601 (1994).

The glossiness of the AG layer is 60% or less, preferably 50% or less. The glossiness of the AG layer is an index of the AG effect. If the glossiness of the AG layer is 60% or less, the AG effect is sufficiently exhibited.
The glossiness of the AG layer is measured by a method defined in 60 ° specular glossiness of JIS Z8741 (1997).

The refractive index of the AG layer is 1.45 or less, preferably 1.37 to 1.45. If the refractive index is 1.45 or less, an AG layer having the same glossiness is advantageous in terms of haze and resolution as compared with a refractive index exceeding 1.45.
The refractive index is a refractive index at 550 nm and is measured by a refractometer.

  The material constituting the AG layer includes, for example, fine particles having a low refractive index and, if necessary, a matrix component. Further, a low refractive index material such as a fluorine-based resin may be used.

Examples of the low refractive index fine particles include hollow SiO ₂ fine particles, airgel fine particles, and hollow polymer fine particles. From the viewpoint of the strength and heat resistance of the AG layer, hollow SiO ₂ fine particles are preferable.
The content of the hollow SiO ₂ particles during AG layer (100 mass%) is preferably from 1 to 70 wt%, more preferably 5 to 50 mass%. If the content of the hollow SiO ₂ fine particles is 1% by mass or more, the AG effect is sufficiently exhibited even if the surface roughness of the AG layer is reduced. When the content of the hollow SiO ₂ fine particles is 70% by mass or less, sufficient adhesion strength with the substrate can be obtained.

The hollow SiO ₂ fine particles are fine particles having voids inside the SiO ₂ outer shell. Examples of the hollow SiO ₂ fine particles include spherical hollow SiO ₂ fine particles, fibrous hollow SiO ₂ fine particles, tubular hollow SiO ₂ fine particles, and sheet-like hollow SiO ₂ fine particles. Fibrous hollow fine SiO ₂ particles, the length of the extending direction is larger hollow SiO ₂ particles as compared to the length in the direction perpendicular to the stretching direction. The fibrous hollow SiO ₂ fine particles may be primary particles or secondary particles in which a plurality of hollow fine particles are aggregated.

The hollow SiO ₂ fine particles may contain other metals. Examples of other metals include Al, Cu, Ce, Sn, Ti, Cr, Co, Fe, Mn, Ni, and Zn. Other metals may form a complex oxide with Si.

The average aggregate particle diameter of the hollow SiO ₂ fine particles is preferably 5 to 300 nm, and more preferably 10 to 100 nm. If the average aggregate particle diameter of the hollow SiO ₂ fine particles exceeds 300 nm, the haze of the AG layer is increased, which is not preferable. If the average aggregate particle diameter of the hollow SiO ₂ fine particles is 300 nm or less, the haze of the AG layer is sufficiently small.
The average agglomerated particle size of the hollow fine SiO ₂ particles is the average agglomerated particle size of the hollow fine SiO ₂ particles in a dispersion medium and is measured by dynamic light scattering method.

The spherical hollow SiO ₂ fine particles are produced, for example, by removing the core of the core-shell particles.
Specifically, it is manufactured through the following steps.
(A) A step of hydrolyzing the SiO ₂ precursor in the presence of the core fine particles in a dispersion medium to precipitate SiO ₂ on the surface of the core fine particles to obtain a dispersion of core-shell particles.
(B) A step of dissolving or decomposing the core of the core-shell particles to obtain a dispersion of spherical hollow SiO ₂ fine particles.

(A) Process:
The core particles include thermally decomposable organic fine particles (surfactant micelles, water-soluble organic polymer, styrene resin, acrylic resin, etc.), acid-soluble inorganic fine particles (ZnO, NaAlO ₂ , CaCO ₃ , basic ZnCO _3, etc.). ), Photosoluble inorganic fine particles (ZnS, CdS, ZnO, etc.) and the like.

Examples of the SiO ₂ precursor include silicic acid, silicate, alkoxysilane and the like.
Examples of the dispersion medium include water, alcohols (methanol, ethanol, isopropanol, etc.), ketones (acetone, methyl ethyl ketone, etc.), ethers (tetrahydrofuran, 1,4-dioxane, etc.), esters (ethyl acetate, acetic acid, etc.). Methyl, etc.), glycol ethers (ethylene glycol monoalkyl ether, etc.), nitrogen-containing compounds (N, N-dimethylacetamide, N, N-dimethylformamide, etc.), sulfur-containing compounds (dimethylsulfoxide, etc.) Etc.

The dispersion medium contains 5 to 100% by mass of water in 100% by mass of the dispersion medium because water is required for hydrolysis of the SiO ₂ precursor.
The pH of the dispersion medium is preferably 7 or more, more preferably 8 or more, and particularly preferably 9 to 10 from the viewpoint that the SiO ₂ precursor is easily three-dimensionally polymerized to form a shell. When acid-soluble inorganic fine particles are used as the core fine particles, a pH at which the fine particles are not dissolved, that is, 8 or more is preferable.

(B) Process:
When the core fine particles are acid-soluble inorganic fine particles, the core fine particles can be dissolved and removed by adding an acid.
Examples of the acid include inorganic acids (hydrochloric acid, sulfuric acid, nitric acid, etc.), organic acids (formic acid, acetic acid, etc.), acidic cation exchange resins, and the like.

Examples of the matrix component in the AG layer include SiO ₂ and organic resins.
Examples of SiO ₂ include those obtained by baking a binder (hydrolyzed polymer of alkoxysilane or hydrolyzed polymer of silane coupling agent) described later.
Examples of the organic resin include a silicone resin and an acrylic resin.

  The article of the present invention described above has an AG layer having a refractive index of 1.45 or less and a surface roughness of 0.04 to 0.17 μm, and thus has a good AG effect. The resolution is small and the haze is sufficiently small. That is, since the AG layer has a refractive index of 1.45 or less, the AG effect is sufficiently exerted even if the surface roughness is smaller than that of the AG layer having a refractive index exceeding 1.45. And since the surface roughness of the AG layer can be made smaller than that of the AG layer having a refractive index exceeding 1.45, even when the AG effect equivalent to that of the AG layer having a refractive index exceeding 1.45 is exhibited. As compared with the AG layer having a refractive index exceeding 1.45, the resolution is less lowered and the haze is sufficiently small.

<Production method>
The method for producing an article of the present invention is a method for forming an antiglare layer by applying a coating solution on a substrate by a spray method and baking it as necessary.

(Coating solution)
The coating liquid is a liquid containing a dispersion medium and a material capable of forming a coating film having a refractive index of 1.45 or less. A material capable of forming a coating film having a refractive index of 1.45 or less is a coating film formed by applying the material on a substrate and firing it as necessary. This is a material having a refractive index N ₁ of 1.45 or less. Examples of the material include a combination of the low refractive index fine particles and a binder which is a precursor of the matrix component (SiO ₂ ); a combination of the low refractive index fine particles and the matrix component (organic resin); Low refractive index materials such as fluorine-based resins; those that have a film containing a large amount of bubbles due to thermal history due to baking or the like after application, or resulting in formation of a coating film having a refractive index of 1.45 or less. .

When the material capable of forming a coating film having a refractive index of 1.45 or less is a combination of the low refractive index fine particles and a binder that is a precursor of the matrix component (SiO ₂ ), the coating liquid is, for example, It can be prepared by mixing a dispersion of fine particles with a low refractive index and a dispersion of a binder.

Examples of the dispersion liquid of the low refractive index fine particles include the dispersion liquid of the spherical hollow SiO ₂ fine particles described above.
Examples of the binder dispersion liquid include a silica sol liquid in which a hydrolysis polymer of alkoxysilane is dispersed in a dispersion medium, and a dispersion liquid in which a hydrolysis polymer of a silane coupling agent is dispersed in a dispersion medium.

Examples of the alkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltrimethoxysilane, and ethyltriethoxysilane.
Examples of the silane coupling agent include an alkoxysilane having a vinyl group (such as vinyltrimethoxysilane), an alkoxysilane having an epoxy group (such as 3-glycidoxypropyltrimethoxysilane), and an alkoxysilane having an acrylic group (3 -Acryloxypropyltrimethoxysilane etc.) etc. are mentioned.

  Examples of the dispersion medium include water, alcohols (methanol, ethanol, isopropanol, etc.), ketones (acetone, methyl ethyl ketone, etc.), ethers (tetrahydrofuran, 1,4-dioxane, etc.), esters (ethyl acetate, acetic acid, etc.). Methyl, etc.), glycol ethers (ethylene glycol monoalkyl ether, etc.), nitrogen-containing compounds (N, N-dimethylacetamide, N, N-dimethylformamide, etc.), sulfur-containing compounds (dimethylsulfoxide, etc.) Etc.

The content of spherical hollow fine SiO ₂ particles, out of the total of the solids in the solids and the binder of the spherical hollow fine SiO ₂ particles constituting the AG layer (100 mass%) is preferably 1 to 70 wt%, 5-50 The mass% is more preferable. When the ratio of the spherical hollow SiO ₂ fine particles is 1% by mass or more, the AG effect is sufficiently exhibited even if the surface roughness of the AG layer is reduced. When the ratio of the spherical hollow SiO ₂ fine particles is 70% by mass or less, sufficient adhesion strength with the substrate can be obtained. When the low refractive index fine particles are hollow SiO ₂ fine particles and the binder is a hydrolysis polymer of alkoxysilane, the solid content is converted to SiO ₂ .

  The solid content concentration of the coating solution is preferably 0.3 to 5.0% by mass, and more preferably 1.0 to 3.0% by mass. If the solid content concentration of the coating solution is 0.3% by mass or more, it is possible to form a concavo-convex film having a sufficient AG effect by a spray method. If the solid content concentration of the coating liquid is 5.0% by mass or less, the film thickness of the uneven film can be sufficiently controlled by the spray method.

(Application method)
As the coating method, the spray method is most suitable.
Examples of the nozzle used in the spray method include a two-fluid nozzle and a one-fluid nozzle.
The particle diameter of the droplet of the coating liquid discharged from the nozzle is usually 0.1 to 100 μm, and preferably 1 to 50 μm. If the particle size of the droplets is 1 μm or more, it is possible to form irregularities that sufficiently exhibit the AG effect in a short time. If the particle size of the droplet is 50 μm or less, it is easy to form moderate unevenness that sufficiently exhibits the AG effect.

The particle size of the droplets can be adjusted as appropriate according to the type of nozzle, spray pressure, liquid volume, and the like. For example, in a two-fluid nozzle, the higher the spray pressure, the smaller the droplet, and the larger the liquid volume, the larger the droplet.
The particle size of the droplet is the Sauter average particle size measured by a laser measuring device.

  The surface roughness of the AG layer can be adjusted by applying time, that is, the number of coated surfaces (number of times of overcoating) by a spray method under a certain application condition. As the number of coated surfaces increases, the surface roughness of the AG layer increases. As a result, the glossiness decreases and the reflected image becomes unclear (AG effect increases), and the haze increases (contrast decreases).

  When applying the coating solution by the spray method, it is preferable to heat the substrate to 30 to 90 ° C. in advance. If the temperature of the substrate is 30 ° C. or higher, the dispersion medium evaporates quickly, so that sufficient unevenness is easily formed. If the temperature of a base material is 90 degrees C or less, the adhesiveness of a base material and AG layer will become favorable. In the case where the substrate is a film or a glass plate having a thickness of 5 mm or less, a heat insulating plate set in advance to a temperature equal to or higher than the temperature of the substrate may be disposed under the substrate to suppress the temperature decrease of the substrate.

  In the method for producing an article of the present invention described above, a coating solution containing a material capable of forming a coating film having a refractive index of 1.45 or less is applied on a substrate by a spray method, and an AG layer is formed. As a result, an article having an AG layer having a good AG effect, little decrease in resolution, and sufficiently small haze can be produced.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.
Examples 1 to 4 are examples, and examples 5 to 7 are comparative examples.

(Average aggregated particle diameter of hollow SiO ₂ fine particles)
The average aggregate particle diameter of the hollow SiO ₂ fine particles was measured using a dynamic light scattering particle size analyzer (manufactured by Nikkiso Co., Ltd., Microtrac UPA).

(Refractive index)
1.5 mL of the coating solution or silica sol solution was applied to the surface of a substrate (manufactured by Asahi Glass Co., Ltd., soda lime glass, 100 mm × 100 mm, thickness 3.4 mm) using a spin coater (manufactured by Mikasa Co., Ltd., IH-360S). . The rotation speed at this time was 300 rpm, and the substrate temperature was room temperature. The film was baked at 300 ° C. for 30 minutes to form a coating film having a thickness of about 100 μm. For coating film, reflectance R reflectometer (manufactured by Otsuka Electronics, MCPD3000) by measuring with light is calculated refractive index _{N 1} of 550nm by the following equation on the assumption that the incident perpendicularly (1).
R = [((N ₁ ) ² −N _o N _s ) ² / ((N ₁ ) ² + N _o N _s ) ² ] (1).
However, N _o is the index of refraction of air, N ₁ is the refractive index of the coating film, N _s is the refractive index of the substrate.
The coating film may be formed by another coating method such as a spray method instead of the spin coating method. However, in the case of a coating film formed by a spray method or the like, depending on the size of the surface unevenness and the surface properties, It may be difficult to measure the reflectivity R of the film. In such a case, instead of measuring the reflectance R of the coating film, the material constituting the coating film is scraped with a sharp object to collect a fine powder, and the fine powder is converted into a standard solution having a known refractive index. The refractive index of the standard solution when mixed and the mixed solution becomes transparent may be the refractive index of the AG layer. In addition, the refractive index of the coating film formed with the same coating liquid does not depend on the coating method. Therefore, instead of directly measuring the reflectance R of the AG layer formed on the substrate by the spray method, the reflectance R of the smooth coating film formed by the spin coating method with the same coating solution is measured. 1) the refractive index N ₁ of the coating film can be regarded as the refractive index of the AG layer calculated by the equation.

(Drop size)
The particle diameter of the droplets was the Sauter average particle diameter measured by a laser measuring device (manufactured by Malvern, Mastersizer S).

(Surface roughness)
The surface roughness of the AG layer (arithmetic average roughness Ra specified in JIS B0601 (1994)) is measured at a substantially central portion of the coat sample using a surface roughness measuring machine (manufactured by Tokyo Seimitsu Co., Ltd., Surfcom 130A). It was measured. The measurement length was 25 mm, and the cut-off value was 0.8 mm.

(Haze)
The haze of the article was measured at a substantially central portion of the coat sample using a haze meter (manufactured by Murakami Color Research Laboratory, model HR-100).

(Glossiness)
The glossiness of the AG layer is a method defined by 60 ° specular glossiness of JIS Z8741 (1997), and a gloss meter (Nippon Denshoku Industries Co., Ltd., PG-3D type) is used, Measured at the center.

(Strength)
The strength (abrasion resistance) of the AG layer was evaluated by the following method.
An eraser (manufactured by Lion Corporation, GAZA1K, vertical 18 mm × width 11 mm) was attached to a rubbing tester (manufactured by Ohira Rika Kogyo Co., Ltd.), and a horizontal reciprocating motion was performed on the AG layer of the coated sample with a 1 kg load. At this time, the area where the eraser hits the AG layer is 198 mm ² (vertically 18 mm × width 11 mm). The appearance of the AG layer after 50 reciprocations was evaluated according to the following criteria.
A: The AG layer is not scratched or slightly scratched.
B: There is a slight scratch on the AG layer.
C: The AG layer has scratches, but there is no peeling of the AG layer.
D: There are scratches in the AG layer, and there is peeling of the AG layer.

(Defocused reflection image)
A black vinyl tape was affixed to the surface of the coated sample on which the AG layer was not formed so as not to contain bubbles. Reflect the reflected image of two 32W fluorescent lamps (Toshiba Corp., Mellow Line 3-wavelength daylight white FHF32EX-N-H) located at a height of 2m on the AG layer side, and visually observe the reflected image. The degree of image blur was evaluated according to the following criteria.
A: The reflected image is not visible or the reflected image is almost invisible.
○: The reflection image is blurred.
Δ: A reflected image is visible.
X: The reflected image is clearly visible.
As the AG effect, it is practically preferable that the degree of blurring of the reflected image is ◎ or ○.

(resolution)
A standard sieve defined by JIS Z8801 (1994) (made by IIDA MANUFACTURING, 125 μm, 90 μm, 75 μm, 63 μm, 53 μm, 45 μm) was prepared.
As shown in FIG. 1, a coat sample 12 was placed in front of a standard sieve 10 having an opening of 125 μm with the surface on which the AG layer was not formed facing the standard sieve 10. A light source 14 (manufactured by Kihara Medical Industry Co., Ltd., medical X-ray photography observation apparatus) was placed 20 cm behind the standard sieve 10. The light source 14 is equipped with four 15 W fluorescent lamps (FL15ECW, manufactured by Matsushita Electric Industrial Co., Ltd.), and the illuminance on the surface of the standard sieve 10 was 3700 lux.

The light transmitted through the standard sieve 10 and the coat sample 12 was visually observed from 15 cm forward of the coat sample 12 to determine whether the eyes of the standard sieve 10 could be identified.
When the eyes of the standard sieve 10 could be identified, the eyes were replaced with a standard sieve having a small eye opening, and the same determination was repeated until the eyes of the standard sieve could no longer be identified. The smallest opening that could be identified was taken as the resolution.
It is practically preferable that the resolution is 75 μm or less.

(Illuminance)
The illuminance was measured using a digital illuminometer (manufactured by Taxco Japan, TMS870).

(Silica sol solution A)
To 7.06 parts by mass of ion-exchanged water, 1.46 parts by mass of 61% by mass nitric acid was added and stirred for 5 minutes to prepare an aqueous nitric acid solution. The nitric acid aqueous solution was added to 80.77 parts by mass of a mixed alcohol composed of 87.9% by mass of ethanol, 10.4% by mass of isopropanol and 1.7% by mass of methyl ethyl ketone, and stirred for 5 minutes to prepare a mixed solution. To this mixed solution, 10.71 parts by mass of tetraethoxysilane was added, stirred and reacted at room temperature for 30 minutes, and a silica sol solution A (solid content concentration 3 in terms of SiO ₂ ) in which a hydrolysis polymer of tetraethoxysilane was dispersed in a dispersion medium. 0.0 mass%) was obtained. The refractive index of the coating film formed from the silica sol solution A was 1.458.

(Dispersion B of spherical hollow SiO ₂ fine particles)
In a glass reaction vessel with a capacity of 200 mL, 39 g of water, 21 g of an aqueous dispersion sol of ZnO fine particles (manufactured by Ishihara Sangyo Co., Ltd., FZO-50, average primary particle size 21 nm, average aggregate particle size 40 nm), tetraethoxysilane (SiO ₂ equivalent solid) After adding 10 g of an aqueous ammonia solution, the pH was adjusted to 10 and the mixture was stirred at 20 ° C. for 6 hours to obtain 100 g of a core-shell particle dispersion (solid content concentration of 6 mass%). .

100 g of a strongly acidic cation exchange resin (trade name: Diaion, total exchange amount of 2.0 mseq / mL or more) is added to the core-shell particle dispersion, and the pH is 4 after stirring for 1 hour. Thereafter, the strongly acidic cationic resin was removed by filtration to obtain 100 g of a spherical hollow SiO ₂ fine particle dispersion.
The outer shell thickness of the spherical hollow SiO ₂ fine particles was 6 nm, and the pore diameter was 30 nm. The spherical hollow SiO ₂ fine particles were aggregate particles, the average aggregate particle diameter was 50 nm, and the solid content concentration in terms of SiO ₂ was 3.0% by mass.
The dispersion of spherical hollow SiO ₂ fine particles is concentrated by ultrafiltration, the dispersion medium is replaced with isopropanol, and dispersion B of spherical hollow SiO ₂ fine particles (dispersion medium: isopropanol, SiO ₂ equivalent solid content concentration 15.0 mass) %).

(Coating liquid C)
To 83.3 parts by mass of silica sol liquid A, 3.3 parts by mass of dispersion B of spherical hollow SiO ₂ fine particles was added with stirring, and further, 87.9% by mass of ethanol, 10.4% by mass of isopropanol and 1. 13.4 parts by mass of a mixed alcohol consisting of 7% by mass was added and stirred at room temperature for 20 minutes to obtain a coating liquid C (SiO ₂ equivalent solid content concentration of 3.0% by mass). The refractive index of the coating film formed from the coating solution C was 1.446.
Further, the content of the spherical hollow SiO ₂ fine particles with respect to the total (100% by mass) of the solid content of the spherical hollow SiO ₂ fine particles and the solid content of the binder was 16.5% by mass.

(Coating solution D)
To 66.7 parts by mass of silica sol solution A, 6.7 parts by mass of dispersion B of spherical hollow SiO ₂ fine particles were added with stirring, and further 87.9% by mass of ethanol, 10.4% by mass of isopropanol and 1. 26.6 parts by mass of a mixed alcohol consisting of 7% by mass was added and stirred at room temperature for 20 minutes to obtain a coating liquid D (SiO ₂ equivalent solid content concentration of 3.0% by mass). The refractive index of the coating film formed from the coating solution D was 1.415.
Further, the content of the spherical hollow SiO ₂ fine particles with respect to the total (100 mass%) of the solid content of the spherical hollow SiO ₂ fine particles and the solid content of the binder was 33.3 mass%.

(Coating fluid E)
To 50.0 parts by mass of silica sol liquid A, 10.0 parts by mass of dispersion B of spherical hollow SiO ₂ fine particles was added with stirring, and further 87.9% by mass of ethanol, 10.4% by mass of isopropanol and 1. 40.0 parts by mass of a mixed alcohol consisting of 7% by mass was added and stirred at room temperature for 20 minutes to obtain a coating liquid E (SiO ₂ equivalent solid content concentration of 3.0% by mass). The refractive index of the coating film formed from the coating solution E was 1.400.
Further, the content of the spherical hollow SiO ₂ fine particles with respect to the total (100% by mass) of the solid content of the spherical hollow SiO ₂ fine particles and the solid content of the binder was 50.0% by mass.

(Coating fluid F)
To 33.3 parts by mass of silica sol liquid A, 13.3 parts by mass of dispersion B of spherical hollow SiO ₂ fine particles were added with stirring, and further, 87.9% by mass of ethanol, 10.4% by mass of isopropanol and 1. 53.4 parts by mass of a mixed alcohol consisting of 7% by mass was added and stirred at room temperature for 20 minutes to obtain a coating liquid F (SiO ₂ equivalent solid content concentration of 3.0% by mass). The refractive index of the coating film formed from the coating solution F was 1.378.
Further, the content of the spherical hollow SiO ₂ fine particles with respect to the total (100% by mass) of the solid content of the spherical hollow SiO ₂ fine particles and the solid content of the binder was 66.7% by mass.

[Example 1]
A glass plate (manufactured by Asahi Glass Co., Ltd., soda lime glass, 100 mm × 100 mm, thickness 3.4 mm) was polished with cerium oxide dispersed in water. The polished glass plate was then polished with a sponge soaked in 2% neutral detergent. Subsequently, the neutral detergent of the glass plate was washed away with clean water, and further rinsed with ion exchange water. Before the ion exchange water on the glass plate was dried, the glass plate was washed with isopropanol to carry out solvent substitution. The glass plate was air-dried at room temperature to obtain a washed glass plate.

The washed glass plate is heated in an oven in advance so that the surface temperature becomes 70 ° C., and after the glass plate is placed at the spray position, the coating liquid C is immediately applied to the glass plate by a spray method under the following conditions. It was applied on top.
Spray pressure: 0.28 MPa,
Liquid volume: 15 mL / min,
Distance from nozzle tip to glass plate: 170mm,
Nozzle moving speed: 750 mm / min,
Spray pitch: 22 mm.

As the spray robot, a 6-axis painting robot (manufactured by Kawasaki Robotics, JF-5) was used.
As the nozzle, a VAU nozzle (manufactured by Spraying System Japan, SUV67B) was used.

The spray pitch and spray pattern are shown in FIG. The nozzle 20 moves laterally on the glass plate 22 at a speed of 750 mm / min, then moves forward 22 mm, and then moves laterally on the glass plate 22 at a speed of 750 nm / min. The nozzle 20 is moved until the nozzle 20 scans the entire surface of the glass plate 22.
A method in which the coating solution is applied to the entire surface of the glass plate by this method is called a one-side coated product. A product obtained by applying a coating solution on the one-side coated product in the same manner is called a two-sided coated product. Similarly, a coated product having three or more surfaces can be obtained by applying the coating on the two-side coated product.

As described above, a 2-side coated product, a 3-side coated product, a 4-side coated product, and a 6-side coated product were produced.
The coated product was baked in an oven at 300 ° C. for 30 minutes to obtain a coated sample. The coat sample was evaluated. The results are shown in Tables 1 and 2.

[Example 2]
A coated sample was obtained in the same manner as in Example 1 except that the coating liquid C was changed to the coating liquid D. The coat sample was evaluated. The results are shown in Tables 1 and 2.

[Example 3]
A coated sample was obtained in the same manner as in Example 1 except that the coating liquid C was changed to the coating liquid E. However, an 8-sided coated product has not been created. The coat sample was evaluated. The results are shown in Tables 1 and 2.

[Example 4]
A coated sample was obtained in the same manner as in Example 1 except that the coating liquid C was changed to the coating liquid F. However, a 4-sided coated product and a 6-sided coated product are not prepared. The coat sample was evaluated. The results are shown in Tables 1 and 2.

[Example 5]
A coated sample was obtained in the same manner as in Example 1 except that the coating liquid C was changed to the silica sol liquid A. Further, a coated sample having 8 coated surfaces was obtained. The coat sample was evaluated. The results are shown in Tables 1 and 2.

[Example 6]
1.5 mL of coating solution A was applied to the surface of a glass plate (Asahi Glass Co., Soda Lime Glass, 100 mm × 100 mm, thickness 3.4 mm) using a spin coater (Mikasa IH-360S). The rotation speed at this time was 300 rpm, and the temperature of the glass plate was room temperature. The film was baked at 300 ° C. for 30 minutes to obtain a spin coat sample AS. The coat sample was evaluated. The results are shown in Table 3.

[Example 7]
A spin coat sample CS was obtained in the same manner as the coating method of the coating liquid A in Example 6 except that the coating liquid was changed to C. The coat sample was evaluated. The results are shown in Table 3.

As shown in Example 5, the coating is made of silica sol solution A that does not contain spherical hollow SiO ₂ fine particles so that it is practically preferable as the AG effect, and the glossiness is 60% or less and the evaluation of the bokeh of the reflected image is ◎ or ○. In this case, a 6-side coating is required, the surface roughness of the AG layer is 0.1 μm or more, and the haze is 4% or more. Further, in the 6-side coated product and the 8-side coated product, the glossiness was 60% or less and the evaluation of the blurred state of the reflected image was ◎, but the resolution was 90 μm or more, and the resolution was remarkably lowered. On the other hand, in Examples 1 to 4, since a coating solution containing spherical hollow SiO ₂ fine particles was used, the AG layer exhibiting the same degree of gloss and reflection image blur as the 6-side coated product of Example 5 had a rough surface. The thickness is less than 0.1 μm, and the haze is also less than 4%. That is, when the surface roughness is 0.04 to 0.1 μm, a practically sufficient reflected image blur can be obtained, and haze that causes a decrease in contrast can be suppressed to less than 4%. Moreover, the resolution is 75 μm or less, which is practically preferable.

Thus, in Examples 1 to 4, if the AG layer has a surface roughness of 0.04 to 0.17 μm and a haze of 6.5% or less, the spherical hollow SiO ₂ fine particles shown in Example 5 are used. An AG layer exhibiting an equivalent glossiness and a blurred state of a reflected image can be obtained with a smaller number of coatings than those coated with silica sol solution A that is not contained. Therefore, if it has the same AG effect (glossiness, blurring of the reflected image), an AG layer can be obtained in which the resolution is less reduced and the haze is sufficiently small.
For example, an AG layer having an AG effect equivalent to that of the 6-side coated product of Example 5 is obtained with the 4-sided coated product of Example 1. Similarly, an AG layer having an AG effect equivalent to that of the 8-side coated product of Example 5 is obtained with the 4-side coated product of Example 2. In addition, these AG layers have a lower resolution and a sufficiently low haze as compared with Example 5.

Further, as in Examples 6 and 7, when the coating solution was applied by the spin coating method, even if the coating solution contained spherical hollow SiO ₂ fine particles, the surface of the coating film was not formed with irregularities. Since it is smooth, the AG effect (glossiness, degree of blur of reflected image) cannot be obtained.

  The article of the present invention is useful as various image display devices (LCD, PDP, etc.), filters or protective plates for image display devices, cover glasses for solar cells, and the like.

It is a figure which shows the evaluation method of the resolution of a coat sample. It is a figure which shows a spray pitch and a spray pattern.

Explanation of symbols

12 Coat sample (article)
22 Glass plate (base material)

Claims (5)

On a substrate, the refractive index is 1.45 or less, and surface roughness have a antiglare layer is 0.04～0.17Myuemu,
The antiglare layer includes hollow SiO ₂ fine particles,
The average agglomerated particle size of the hollow SiO ₂ particles, Ru 5~300nm der article. The article according to claim 1, wherein the content of the hollow SiO ₂ fine particles is 1 to 70 mass% in the antiglare layer (100 mass%). The article according to claim 1 or 2 , wherein the haze is less than 6.5%. The article according to any one of claims 1 to 3 , wherein the antiglare layer has a glossiness of 60% or less. It is a manufacturing method of the article according to any one of claims 1 to 4 ,
The manufacturing method of the articles | goods which apply | coats the coating liquid containing the material which can form the coating film whose refractive index is 1.45 or less on the said base material by the spray method, and forms the said anti-glare layer.

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