CN118550010A - Anti-reflection film and image display device - Google Patents

Abstract

The present invention relates to an anti-reflection film and an image display device. The anti-reflection film (101) comprises: a hard coating film (1) having a hard coating layer (11) on one main surface of a transparent film substrate (10), an anti-reflection layer (5) and an anti-fouling layer (7) sequentially arranged on the hard coating layer (11). The hard coating layer comprises a binder resin, micron particles having an average primary particle size of 1 to 8 μm, and nanoparticles having an average primary particle size of 100 nm or less. The anti-reflection layer is formed by a stack of multiple films having different refractive indices. The average spacing RSm of the concavities and convexities of the anti-reflection film obtained from a roughness curve having a measured length of 12 mm is greater than 120 μm, and the arithmetic mean height Sa obtained from the three-dimensional surface properties of a 1 μm×1 μm region is greater than 2.0 nm.

Description

Anti-reflection film and image display device

Technical Field

The present invention relates to an antireflection film having an antireflection layer on a transparent film substrate and an image display device having the antireflection film.

Background Art

Anti-reflection films are used on the visual recognition side surface of image display devices such as liquid crystal displays and organic EL displays to prevent image quality degradation caused by reflection of external light and to improve contrast. Anti-reflection films have an anti-reflection layer formed by a laminate of multiple films with different refractive indices on a transparent film.

In order to prevent the contrast from being reduced due to the reflected glare of external light, there is a method of implementing an antiglare treatment. For example, in Patent Documents 1 to 3, an antiglare anti-reflection film having an anti-reflection layer provided on an anti-glare hard-coated film having a hard-coated layer containing microparticles formed on a transparent film is disclosed. The antiglare anti-reflection film forms a surface unevenness by making the hard-coated layer contain microparticles (micron particles) with a particle size of μm level, so that external light is scattered and reflected, thereby reducing the reflected glare of external light.

Patent documents 1 to 3 disclose that the anti-glare hard coating layer contains nanoparticles with an average primary particle size of less than 100 nm in addition to micron particles. Patent document 1 records that the light diffusion of the surface is improved by aggregating silica particles with an average primary particle size of 20 nm to form amorphous secondary particles. Patent document 2 records that the surface-modified nano-silica particles have the function of inhibiting the sedimentation of organic particles (micron particles) and making them float to the surface, so the anti-glare property can be adjusted. Patent document 3 (refer to Examples 6 to 8) records that the anti-glare hard coating layer contains nano-silica particles, so that the surface of the hard coating layer forms fine concave-convex, and the adhesion between the hard coating layer and the anti-reflection layer is improved.

Prior art literature

Patent Literature

Patent Document 1: Japanese Patent Application Publication No. 2008-40064

Patent Document 2: Japanese Patent Application Publication No. 2009-204728

Patent Document 3: International Publication No. 2021/106797

Summary of the invention

Problem that the invention aims to solve

Conventional antiglare antireflection films have the following problems: the adhesion between the hard coat layer and the antireflection layer is low, the antireflection layer (and the antifouling layer provided thereon) is easily peeled off when exposed to external light for a long time, and the optical properties and antifouling properties are reduced with use.

As proposed in Patent Document 3, by making nanoparticles present on the surface of the anti-glare hard coating, the adhesion between the hard coating and the anti-reflection layer tends to be improved. However, although the anti-reflection films of Examples 6 to 8 of Patent Document 3 have good adhesion to the anti-reflection layer, when the image display device displays black, the reflected light of the external light appears whitish and blurred (white halo), the density of the color displayed in black is poor, and the contrast of the bright area is low.

In view of the above circumstances, an object of the present invention is to provide an antireflection film having high adhesion between an antiglare hard coat layer and an antireflection layer, less halation of reflected light, and good visibility.

Solutions for solving problems

The antireflection film of the present invention comprises: a hard coating film having a hard coating layer on one main surface of a transparent film substrate, an antireflection layer and an antifouling layer sequentially provided on the hard coating layer. The hard coating layer comprises a binder, microparticles (microparticles) having a particle size of 1 to 8 μm, and microparticles (nanoparticles) having an average primary particle size of 100 nm or less.

The anti-reflection layer is formed by a laminate of multiple thin films with different refractive indices. The thin film constituting the anti-reflection layer is preferably an inorganic oxide. The anti-reflection layer can be a sputtering film formed by sputtering. A primer layer formed by an inorganic oxide can be provided between the hard coat layer and the anti-reflection layer.

The surface of the antireflection film (the surface of the antifouling layer) preferably has an average interval RSm of concavities and convexities obtained from a roughness curve measuring a length of 12 mm of 120 μm or more, and preferably has an arithmetic mean height Sa obtained from a three-dimensional surface property of a 1 μm×1 μm region of 2.0 nm or more. The arithmetic mean roughness Ra of the surface of the antireflection film obtained from a roughness curve measuring a length of 12 mm may also be 30 to 500 nm.

The specific gravity of the micron particles contained in the hard coat layer is preferably 1.25 or more. When the hard coat layer contains two or more micron particles, the average specific gravity of the micron particles is preferably 1.25 or more, and in a total of 100 parts by weight of the micron particles, the ratio of particles with a specific gravity of 1.25 or more is preferably 85 parts by weight or more.

The amount of microparticles in the hard coat layer is preferably 0.5 to 12 parts by weight relative to 100 parts by weight of the binder resin. The amount of nanoparticles in the hard coat layer is preferably 25 to 120 parts by weight relative to 100 parts by weight of the binder. The average primary particle size of the nanoparticles is preferably 15 nm or more.

Effects of the Invention

The hard coating layer of the anti-reflection film having the above-mentioned Sa and RSm has high adhesion to the anti-reflection layer, exhibits high anti-glare properties, has little white halo of reflected light, and has good visual recognition. The image display device having the anti-reflection film disposed on the visual recognition side surface of the image display medium shows excellent anti-glare properties, high contrast in bright areas, and the anti-reflection layer and the anti-fouling layer are difficult to peel off, so that the excellent optical properties and anti-fouling properties can be maintained even after long-term use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an example of a laminated structure of an antireflection film.

FIG. 2 is a photograph showing observation of reflected light of the antireflection films of Examples and Comparative Examples.

Description of Reference Numerals

1 Hard coating film

10 Transparent film substrate

11 Hard coating

3 Primer layer

5 Anti-reflection layer

51, 53 High refractive index layer

52, 54 Low refractive index layer

7 Antifouling layer

101 Anti-reflection film

DETAILED DESCRIPTION

FIG1 is a cross-sectional view showing an example of a laminated structure of an anti-reflection film according to an embodiment of the present invention. The anti-reflection film 101 includes an anti-reflection layer 5 on a hard coating layer 11 of a hard coating film 1, and an antifouling layer 7 on the anti-reflection layer 5. The hard coating film 1 includes a hard coating layer 11 on one main surface of a transparent film substrate 10. The anti-reflection layer 5 is a laminate of two or more inorganic thin films having different refractive indices. A primer layer 3 may also be provided between the hard coating layer 11 and the anti-reflection layer 5.

[Hard Coat Film]

The hard coat film 1 includes a hard coat layer 11 on one main surface of a transparent film substrate 10. By providing the hard coat layer 11 on the surface where the antireflection layer 5 is formed, mechanical properties such as surface hardness and scratch resistance of the antireflection film can be improved.

＜Transparent film substrate＞

The visible light transmittance of the transparent film substrate 10 is preferably 80% or more, more preferably 90% or more. As the resin material constituting the transparent film substrate 10, for example, a resin material having excellent transparency, mechanical strength and thermal stability is preferred. Specific examples of the resin material include cellulose resins such as triacetyl cellulose, polyester resins, polyethersulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth)acrylic resins, cyclic polyolefin resins (norbornene resins), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof.

The thickness of the transparent film substrate is not particularly limited, but is preferably about 5 to 300 μm, more preferably 10 to 250 μm, and even more preferably 20 to 200 μm from the viewpoints of strength, handling properties such as handling efficiency, and thinness.

＜Hard coating＞

The hard coating film 1 is formed by providing a hard coating layer 11 on the main surface of the transparent film substrate 10. The hard coating layer 11 contains a binder resin and fine particles, and the fine particles contain microparticles with a particle size of 1 μm or more and nanoparticles with a particle size of 100 nm or less. The hard coating layer 11 exerts anti-glare properties through the surface concavo-convex formed by the microparticles, and the fine surface concavo-convex formed by the nanoparticles helps to improve the adhesion of the anti-reflection layer 5.

The thickness of the hard coating layer 11 is not particularly limited. In order to achieve high hardness, it is preferably 2 μm or more, more preferably 4 μm or more, and further preferably 5 μm or more. On the other hand, when the thickness of the hard coating layer 11 is too large, the surface unevenness of the hard coating layer may not be properly formed, and the film strength may be reduced due to cohesive failure. Therefore, the thickness of the hard coating layer 11 is preferably 20 μm or less, more preferably 15 μm or less, and further preferably 12 μm or less. In addition, the thickness of the hard coating layer 11 is preferably in the range of 1.2 to 4 times the average particle size of the micron particles, and more preferably in the range of 1.5 to 3 times. By making the ratio of the particle size of the micron particles to the thickness of the hard coating layer in the above range, the uneven shape formed on the surface of the hard coating layer is easy to become an uneven shape with excellent anti-glare properties.

The haze of the hard coating film is preferably 1 to 35%, more preferably 2 to 30%, and may also be 3 to 25%, 4 to 20%, 5 to 17%, or 6 to 15%. When the haze of the hard coating film is within the above range, both anti-glare properties and image clarity can be achieved. When the haze is too small, the anti-glare properties may be poor, and when the haze is too large, there is a tendency that the scattering of the transmitted light is large and the image clarity is reduced.

The arithmetic mean height Sa calculated from the three-dimensional surface properties of the 1 μm×1 μm region of the hard coating layer 11 is preferably 2.0 nm or more. The average interval RSm of the concavities and convexities calculated from the roughness curve of the measurement length of 12 mm is preferably 120 μm or more.

The arithmetic mean height Sa is a value calculated according to ISO25178 from an observation image of 1 μm square using an atomic force microscope (AFM), and is an indicator of the degree of formation of fine concavoconvexities on the nm scale. There is a tendency that the larger the arithmetic mean height Sa of the hard coating layer 11, the higher the adhesion of the anti-reflection layer 5. There is a tendency that the larger the particle size of the nanoparticles contained in the hard coating layer 11 and the more the content of the nanoparticles, the larger Sa. The arithmetic mean height Sa of the hard coating layer 11 is more preferably 2.3 nm or more, further preferably 2.5 nm or more, and may also be 2.7 nm or more, 2.9 nm or more, or 3.0 nm or more.

On the other hand, when the surface concavo-convex formed by nanoparticles becomes coarse, sufficient adhesion cannot be achieved sometimes. In addition, when the surface concavo-convex formed by nanoparticles becomes large, the shape of micron particles is difficult to be reflected on the surface shape of hard coat 11 sometimes, and anti-glare property reduces. Therefore, the arithmetic mean height Sa of hard coat 11 is preferably below 10nm, more preferably below 8.0nm, further preferably below 7.0nm, and can also be below 6.0nm, below 5.5nm, below 5.0nm or below 4.5nm.

The average interval RSm of the concavoconvex is: the roughness curve obtained by passing a cross-sectional curve of a length of 12 mm measured by a stylus-type surface roughness measuring instrument through a wide-area filter with a cutoff value of 0.8 mm, the average length of the roughness curve element calculated according to JIS B0601:2001, is an index representing the surface density of the concavoconvex on the μm scale. The smaller the average interval RSm of the concavoconvex in the hard coating layer 11, the higher the density of the concavoconvex formed on the surface of the hard coating layer by micron particles, and the more excellent the anti-glare property tends to be. On the other hand, when RSm is too small, there is a tendency that the reflected image of the external light tends to look whitish and blurred, the "density" of black is poor, and the contrast in the bright area is reduced when the image display device is displayed in black (refer to "Comparative Example 2" in Figure 2).

The average interval RSm of the concavities and convexities of the hard coat layer 11 is 120 μm or more, so that the density of black is good and a display with high contrast in bright areas can be achieved. The average interval RSm of the concavities and convexities of the hard coat layer 11 is more preferably 130 μm or more, and may be 140 μm or more or 150 μm or more.

On the other hand, when the average interval RSm of the concavoconvex of the hard coating layer 11 is too large, the anti-glare property may not be fully exerted. Therefore, the average interval RSm of the concavoconvex of the hard coating layer 11 is preferably 250 μm or less, more preferably 220 μm or less, further preferably 200 μm or less, and may be 180 μm or less or 170 μm or less.

The surface of the hard coating layer 11 preferably has an arithmetic mean roughness Ra of 30 to 500 nm calculated in accordance with JIS B0601: 2001 from a roughness curve obtained by passing a cross-sectional curve having a measurement length of 12 mm through a wide-area filter having a cutoff value of 0.8 mm. The arithmetic mean roughness Ra is an index indicating the degree of formation of submicron to μm-scale high concavities and convexities that contribute to light scattering, and there is a tendency that the larger the particle size of the micron particles contained in the hard coating layer 11 and the greater the content of the micron particles, the larger the Sa.

There is a tendency that the greater the arithmetic mean roughness Ra of the hard coating layer 11, the better the anti-glare property. On the other hand, when the arithmetic mean roughness Ra of the hard coating layer 11 is too large, light scattering is large, which may cause a decrease in image clarity and a white halo of reflected light. The arithmetic mean roughness Ra of the hard coating layer 11 is more preferably 50 to 400 nm, further preferably 60 to 300 nm, and may also be 70 to 250 nm or 80 to 200 nm.

The composition for forming the hard coating layer 11 contains a binder resin (or a curable resin as a precursor thereof), microparticles having a particle diameter of 1 μm or more, and nanoparticles having a particle diameter of 100 nm or less.

(Binder resin)

As the binder resin of the hard coat layer 11, it is preferred to use a curable resin such as a thermosetting resin, a photocurable resin, an electron beam curable resin, etc. As the types of curable resins, polyester, acrylic, urethane, acrylic urethane, amide, silicone, silicate, epoxy, melamine, oxetane, acrylic urethane, etc. can be cited. Among them, acrylic resins, acrylic urethane resins and epoxy resins are preferred from the viewpoint of high hardness and photocurability, and acrylic resins and acrylic urethane resins are preferred. The refractive index of the binder resin is generally about 1.4 to 1.6.

The photocurable binder resin component contains a polyfunctional compound having two or more photopolymerizable (preferably ultraviolet-polymerizable) functional groups. The polyfunctional compound may be a monomer or an oligomer. As the photopolymerizable polyfunctional compound, a compound containing two or more (meth)acryloyl groups in one molecule (polyfunctional (meth)acrylate) is preferably used.

(Micron particles)

The hard coat layer 11 contains microparticles (microparticles) with a particle size of 1 μm or more, thereby forming periodic concavities and convexities of about 100 μm on the surface of the hard coat layer, thereby imparting anti-glare properties. The average particle size of the microparticles (particles with a particle size of 1 μm or more) contained in the hard coat layer is preferably 1 to 8 μm, more preferably 2 to 5 μm. When the particle size of the microparticles is small, there is a tendency for insufficient anti-glare properties. When the particle size of the microparticles is large, there is a tendency for the clarity of the image to decrease. When the hard coat layer contains two or more types of microparticles, it is preferred that the average particle size of the entire microparticles (particles with a particle size of 1 μm or more) is within the above range. The average particle size is a weight-average particle size measured by the Coulter counter method.

The shape of the micronized particles is not particularly limited, but from the viewpoint of reducing glare, spherical particles having an aspect ratio of 1.5 or less are preferred. The aspect ratio of the spherical particles is preferably 1.3 or less, more preferably 1.1 or less.

As the material of the micron particles, various metal oxide particles such as silicon dioxide, aluminum oxide, titanium dioxide, zirconium oxide, calcium oxide, tin oxide, indium oxide, cadmium oxide, antimony oxide, glass particles, crosslinked or uncrosslinked organic particles formed by various transparent polymers such as polymethyl methacrylate, polystyrene, polyurethane, acrylic-styrene copolymer, benzoguanamine, melamine, polycarbonate, silicone, etc. can be used without particular limitation. These micron particles can be appropriately selected to use one or more. From the aspect of being able to produce micron particles with a particle size of μm level and a small aspect ratio, high uniformity of particle size, and high density, silicone is particularly preferred as the material of the micron particles.

It is preferred that the refractive index difference between the micron particles and the binder resin of the hard coat is small. By reducing the refractive index difference between the binder and the micron particles, the light scattering at the interface of the binder resin and the micron particles is reduced, and the haze is reduced, so that a high-definition display can be achieved. On the other hand, when the haze of the hard coat is too small, the anti-glare property sometimes becomes insufficient. From the viewpoint of making the hard coat have a moderate haze and achieving a high-definition display, the refractive index difference between the binder resin and the micron particles is preferably about 0.01 to 0.10, and can also be 0.02 to 0.06.

The specific gravity of the micron particles is preferably 1.25 or more, more preferably 1.28 or more, and may be 1.30 or more. The specific gravity of the micron particles may also be 2.0 or less, 1.70 or less, 1.50 or less, or 1.40 or less. The specific gravity of the micron particles is preferably greater than that of the nanoparticles.

When the specific gravity of the micron particles is large, the micron particles tend to settle and are concentrated near the transparent film substrate 10. In conjunction with this, the nanoparticles are concentrated near the surface of the hard coating layer 11 (the interface with the anti-reflection layer 5 or the primer layer 3) and form fine concavo-convex shapes uniformly in the surface, so there is a tendency for the adhesion of the anti-reflection layer to be improved.

In the case where micron particles and nanoparticles coexist in the hard coating layer 11, when the micron particles exist near the surface of the hard coating layer, the average interval RSm of the surface concavities and convexities becomes smaller, and there is a tendency that the contrast of the bright part is reduced due to the white halo of the reflected light. By using micron particles with a large specific gravity and easy sedimentation, there is a tendency that the interval of the concavities and convexities formed on the surface of the hard coating layer reflecting the shape of the micron particles becomes larger, and RSm becomes larger.

In the case of containing more than two kinds of micron particles in the hard coat, it is preferred that the average specific gravity of the micron particles (particles with a particle size of 1 μm or more) is within the above range. Even if the average specific gravity of the micron particles is more than 1.25, when the ratio of the micron particles with a specific gravity less than 1.25 is large, there is a tendency that the amount of micron particles present near the surface of the hard coat becomes more and the RSm of the hard coat becomes smaller. Therefore, in a total of 100 parts by weight of micron particles, the amount of particles with a specific gravity of more than 1.25 is preferably more than 85 parts by weight, more preferably more than 90 parts by weight, and can also be more than 95 parts by weight, more than 99 parts by weight, or 100 parts by weight.

The content of micron particles in the hard coat layer is not particularly limited. From the viewpoint of uniformly forming unevenness on the surface of the hard coat layer, the content of micron particles is preferably 0.5 to 12 parts by weight, more preferably 1 to 10 parts by weight, and may also be 1.5 to 7 parts by weight or 2 to 5 parts by weight relative to 100 parts by weight of the binder resin. When the content of micron particles is small, the RSm of the hard coat layer is sometimes large and the anti-glare property is insufficient. On the other hand, when the content of micron particles is too large, even if high-density micron particles are used, there is a tendency for RSm to become smaller and the contrast in bright areas to decrease due to the white halo of reflected light.

As described above, by adjusting the specific gravity, particle size and content of micron particles, the surface shape of the hard coat layer 11 can be adjusted, anti-glare properties can be imparted, and white halo can be reduced. The more the content of micron particles, the more the number of convex portions formed by the micron particles becomes, so there is a tendency for RSm to become smaller. In addition, there is a tendency for Ra to become larger as the average particle size of the micron particles is larger and the content of the micron particles is more. When the specific gravity of the micron particles is small and the ratio of the micron particles present near the surface is large, there is a tendency for RSm to become smaller and Ra to become larger.

(Nanoparticles)

The hard coating layer 11 contains nanoparticles having a particle size of 100 nm or less in addition to microparticles having a particle size of 1 μm or more, thereby forming fine concavo-convexities on the surface of the hard coating layer that are smaller in size than the concavo-convexities formed by the microparticles, and there is a tendency for the adhesion between the hard coating layer 11 and the anti-reflection layer 5 formed thereon to be improved.

As the material of nanoparticles, inorganic oxides are preferred. As inorganic oxides, metal or semimetal oxides such as silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, titanium oxide, niobium oxide, zinc oxide, tin oxide, cerium oxide, magnesium oxide, etc. can be listed. The inorganic oxide can be a composite oxide of multiple (semi) metals. Among the exemplified inorganic oxides, silicon oxide is preferred from the viewpoint of low refractive index, excellent transparency, and high adhesion improvement effect. Among them, colloidal silica is particularly preferred as the material of nanoparticles from the perspective of being able to produce micron particles with high uniformity of particle size, excellent dispersibility, and low density. For the purpose of improving affinity with binder resin, improving the hardness of hard coating, etc., functional groups such as acryloyl and epoxy groups can also be introduced on the surface of nanoparticles.

The specific gravity of the nanoparticles is preferably smaller than that of the micron particles. The nanoparticles have a relatively low specific gravity, so that the nanoparticles tend to be more heavily present near the surface of the hard coating layer 11, and fine concavoconvexities are uniformly formed in the surface, thereby having a tendency to improve the adhesion of the anti-reflection layer. The specific gravity of the nanoparticles is preferably less than 1.25, and can be less than 1.23 or less than 1.21. The specific gravity of the nanoparticles can also be greater than 0.80, greater than 0.90, greater than 0.95, or greater than 1.00. The specific gravity of colloidal silica is generally about 1.05 to 1.20.

The larger the particle size of the nanoparticles and the higher the content of the nanoparticles, the greater the height and surface density of the nano-sized concavities and convexities formed by the nanoparticles, the greater the arithmetic mean height Sa of the hard coating layer 11 becomes, and the adhesion of the antireflection layer 5 tends to improve accordingly.

From the viewpoint of improving the dispersibility in the binder and increasing the Sa of the hard coat to improve the adhesion of the anti-reflection layer, the average primary particle size of the nanoparticles is preferably more than 15nm, more preferably more than 20nm, and can also be more than 25nm or more than 30nm. On the other hand, from the viewpoint of forming a fine concavo-convex shape that contributes to the improvement of adhesion and suppressing the colored reflected light on the hard coat surface, the average primary particle size of the nanoparticles is preferably less than 90nm, more preferably less than 70nm, and can also be less than 60nm, less than 55nm or less than 50nm.

The content of nanoparticles in the hard coat is not particularly limited. From the viewpoint of increasing the Sa of the hard coat to improve the adhesion of the anti-reflection layer, the content of nanoparticles is preferably 25 parts by weight or more relative to 100 parts by weight of the binder resin, and may be 30 parts by weight or more or 35 parts by weight or more. On the other hand, when the content of nanoparticles is too large, the RSm of the hard coat becomes small, and it is easy to produce a white halo of reflected light. Therefore, the content of nanoparticles in the hard coat is preferably 120 parts by weight or less, more preferably 100 parts by weight or less, and further preferably 80 parts by weight or less relative to 100 parts by weight of the binder resin, and may be 70 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, or 45 parts by weight or less.

(Formation of hard coat layer)

The hard coating composition comprises the above-mentioned binder resin component, micron particles and nanoparticles, and a solvent as required. When the binder resin component is a curable resin, the composition preferably contains an appropriate polymerization initiator. For example, when the binder resin component is a photocurable resin, the composition preferably contains a photopolymerization initiator.

The hard coating composition may contain additives such as a leveling agent, a viscosity modifier (thixotropic agent, thickener, etc.), an antistatic agent, an antiblocking agent, a dispersant, a dispersion stabilizer, an antioxidant, a UV absorber, a defoaming agent, a surfactant, a lubricant, etc. in addition to the above.

As thixotropic agents, organic clay, oxidized polyolefin, modified urea, etc. can be listed. Among them, organic clay such as montmorillonite is preferred. The amount of thixotropic agent mixed is preferably about 0.3 to 5 parts by weight relative to 100 parts by weight of the binder. As leveling agents, for example, fluorine-based or silicone-based leveling agents can be listed, and the amount of the leveling agent mixed is preferably about 0.01 to 3 parts by weight relative to 100 parts by weight of the binder.

The hard coating composition is applied onto the transparent film substrate 10 , and the solvent is removed and the resin is cured as necessary, thereby forming the hard coating layer 11 .

As a coating method for the hard coating composition, any appropriate method such as rod coating, roll coating, gravure coating, rod coating, slot coating, curtain coating, injection coating, comma coating, etc. can be adopted. The heating temperature after coating can be set to an appropriate temperature according to the composition of the hard coating composition, for example, about 50°C to 150°C. When the binder resin component is a photocurable resin, photocuring is performed by irradiating active energy rays such as ultraviolet rays. The cumulative light amount of the irradiated light is, for example, about 100 to 500 mJ/ ^cm2 .

Before forming the anti-reflection layer 5 on the hard coating layer 11, for the purpose of further improving the adhesion between the hard coating layer 11 and the anti-reflection layer 5, the surface treatment of the hard coating layer 11 can also be performed. As the surface treatment, surface modification treatments such as corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, glow treatment, alkali treatment, acid treatment, and treatment using a coupling agent can be listed. As the surface treatment, vacuum plasma treatment can be performed. In the dry etching process using vacuum plasma, the resin component on the surface of the hard coating layer is easily selectively etched, and the presence ratio of nanoparticles on the surface of the hard coating layer and its vicinity becomes higher, so there is a tendency for the arithmetic mean height Sa of the hard coating layer surface to become larger.

[Anti-reflection film]

An antireflection film can be obtained by forming an antireflection layer 5 on the hard coat layer 11 of the hard coat film 1 via a primer layer 3 as needed, and forming an antifouling layer 7 on the antireflection layer 5 .

＜Primer layer＞

It is preferred to provide a primer layer 3 between the hard coating layer 11 and the anti-reflection layer 5. As the material of the primer layer 3, metals such as silicon, nickel, chromium, tin, gold, silver, platinum, zinc, titanium, indium, tungsten, aluminum, zirconium, palladium, etc. can be listed; alloys of these metals; oxides, fluorides, sulfides or nitrides of these metals, etc. Among them, the material of the primer layer is preferably an inorganic oxide, and silicon oxide or indium oxide is particularly preferred. The inorganic oxide constituting the primer layer 3 can be a composite oxide such as indium tin oxide (ITO).

When the primer layer 3 is silicon oxide, a material having a lower oxygen content than the stoichiometric composition is particularly preferred from the viewpoint of high light transmittance and high adhesion to both the organic layer (hard coat layer) and the inorganic layer (anti-reflection layer). The oxygen content of the primer layer 3 of the non-stoichiometric composition is preferably about 60 to 99% of the stoichiometric composition. For example, when a silicon oxide (SiO _x ) layer is formed as the primer layer 3, x is preferably 1.20 to 1.98.

The thickness of the primer layer 3 is, for example, about 1 to 20 nm, preferably 3 to 15 nm. When the thickness of the primer layer is within the above range, both adhesion to the hard coat layer 11 and high light transmittance can be achieved.

＜Anti-reflection layer＞

The anti-reflection layer 5 is formed by two or more thin films with different refractive indices. Generally speaking, the anti-reflection layer adjusts the optical film thickness (the product of the refractive index and the thickness) of the thin film in such a way that the inverted phases of the incident light and the reflected light cancel each other out. By making the anti-reflection layer a multilayer laminate of two or more thin films with different refractive indices, the reflectivity can be reduced within the wavelength range of a wide band of visible light.

As the material of the thin film constituting the anti-reflection layer 5, metal oxides, nitrides, fluorides, etc. can be listed. The anti-reflection layer 5 is preferably an alternating laminate of high refractive index layers and low refractive index layers. In order to reduce the reflection at the interface with the antifouling layer, the thin film 54 provided as the outermost layer of the anti-reflection layer 5 is preferably a low refractive index layer.

The high refractive index layers 51 and 53 have a refractive index of, for example, 1.9 or more, preferably 2.0 or more. Examples of high refractive index materials include titanium oxide, niobium oxide, zirconium oxide, tantalum oxide, zinc oxide, indium oxide, indium tin oxide (ITO), antimony-doped tin oxide (ATO), and the like. Among them, titanium oxide or niobium oxide is preferred. The low refractive index layers 52 and 54 have a refractive index of, for example, 1.6 or less, preferably 1.5 or less. Examples of low refractive index materials include silicon oxide, titanium nitride, magnesium fluoride, barium fluoride, calcium fluoride, hafnium fluoride, and lanthanum fluoride. Among them, silicon oxide is preferred. It is particularly preferred to alternately stack niobium oxide (Nb ₂ O ₅ ) thin films 51 and 33 as high refractive index layers and silicon oxide (SiO ₂ ) thin films 52 and 54 as low refractive index layers. In addition to the low refractive index layer and the high refractive index layer, a medium refractive index layer having a refractive index of about 1.6 to 1.9 may also be provided.

The film thickness of the high refractive index layer and the low refractive index layer is about 5 to 200 nm, preferably about 15 to 150 nm. The film thickness of each layer can be designed in a manner such that the reflectivity of visible light decreases according to the refractive index, the stacked structure, etc. For example, as the stacked structure of the high refractive index layer and the low refractive index layer, a 4-layer structure of a high refractive index layer 51 with an optical film thickness of about 25 nm to 55 nm, a low refractive index layer 52 with an optical film thickness of about 35 nm to 55 nm, a high refractive index layer 53 with an optical film thickness of about 80 nm to 240 nm, and a low refractive index layer 54 with an optical film thickness of about 120 nm to 150 nm can be cited from the side of the hard coating film.

The film forming method of the thin film constituting the anti-reflection layer 5 is not particularly limited, and can be any of a wet coating method and a dry coating method. From the aspect of being able to form a thin film with uniform film thickness, dry coating methods such as vacuum evaporation, CVD, sputtering, and electron beam evaporation are preferred. Among them, from the viewpoint of being easy to form a film with excellent uniformity of film thickness, dense and high strength, a sputtering method is preferred. By forming the anti-reflection layer by sputtering, there is a tendency that the wear resistance of the antifouling layer 7 disposed on the anti-reflection layer 5 is improved.

In the sputtering method, a long hard coating film can be transported in one direction (length direction) by a roll-to-roll method while continuously forming a film. In the sputtering method, an inert gas such as argon and a reactive gas such as oxygen as required are introduced into the chamber while film formation is performed. The film formation of the oxide layer using the sputtering method can be implemented by any of the methods using an oxide target and reactive sputtering using a metal target. In order to form a metal oxide film at a high rate, reactive sputtering using a metal target is preferably used.

＜Antifouling layer＞

The antireflection film includes an antifouling layer 7 as the outermost layer (top coat) on the antireflection layer 5. Providing the antifouling layer on the outermost surface can reduce the influence of pollution (fingerprints, hand dirt, dust, etc.) from the external environment and facilitate the removal of pollutants attached to the surface.

In order to maintain the antireflection property of the antireflection layer 5, the antifouling layer 7 preferably has a small refractive index difference with the outermost low refractive index layer 54 of the antireflection layer 5. The refractive index of the antifouling layer 7 is preferably 1.6 or less, more preferably 1.55 or less.

As the material of the antifouling layer 7, a fluorine-containing compound is preferred. Fluorine-containing compounds can impart antifouling properties and can also contribute to low refractive index. Among them, from the viewpoint of excellent water repellency and high antifouling properties, a fluorine-based polymer containing a perfluoropolyether skeleton is preferred. From the viewpoint of improving antifouling properties, a perfluoropolyether having a main chain structure that can be rigidly arranged is particularly preferred. As a structural unit of the main chain skeleton of a perfluoropolyether, a perfluoroalkylene oxide having a branched chain with 1 to 4 carbon atoms is preferred, for example, perfluoromethylene oxide, (-CF ₂ O-), perfluoroethylene oxide (-CF ₂ CF ₂ O-), perfluoropropylene oxide (-CF ₂ CF ₂ CF ₂ O-), perfluoroisopropylene oxide (-CF(CF ₃ )CF ₂ O-), etc. can be listed.

The antifouling layer can be formed by a wet method such as a reverse coating method, a die coating method, a gravure coating method, or a dry method such as a vacuum evaporation method or a CVD method. The thickness of the antifouling layer is usually about 2 to 50 nm. There is a tendency that the greater the thickness of the antifouling layer 7, the more the antifouling property is improved. In addition, there is a tendency that the greater the thickness of the antifouling layer 7, the more the specific reduction of the antifouling caused by wear is suppressed. The thickness of the antifouling layer is preferably 3 nm or more, and may also be 5 nm or more or 7 nm or more. On the other hand, from the viewpoint of forming a surface shape reflecting the concave-convex shape of the hard coating surface on the surface of the antifouling layer and improving the anti-glare property, the thickness of the antifouling layer is preferably 30 nm or less, more preferably 20 nm or less, and may also be 15 nm or less.

In order to improve the anti-fouling property and the pollutant removal property, the water contact angle of the anti-fouling layer 7 is preferably 100° or more, more preferably 102° or more, and further preferably 105° or more. The larger the water contact angle, the higher the water repellency, and there is a tendency to improve the effect of preventing the adhesion of pollutants and the pollutant removal property. The water contact angle is generally 125° or less.

＜Surface shape of anti-reflection film＞

The arithmetic mean height Sa of the surface of the antireflection film, i.e., the surface of the antifouling layer 7, calculated from the three-dimensional surface properties of the region of 1 μm×1 μm, is preferably 2.0 nm or more. The arithmetic mean height Sa of the surface of the antifouling layer 7 is more preferably 2.3 nm or more, further preferably 2.5 nm or more, and may be 2.7 nm or more, 2.9 nm or more, or 3.0 nm or more. The arithmetic mean height Sa of the surface of the antifouling layer 7 is preferably 10 nm or less, more preferably 8.0 nm or less, further preferably 7.0 nm or less, and may be 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, or 4.5 nm or less.

The thickness of the antireflection layer 5 and the antifouling layer 7 formed on the hard coating layer 11 is small, so it is easy to form a concavo-convex shape reflecting the surface shape of the hard coating layer 11 on the surface of the antifouling layer 7. Therefore, by adjusting the particle size and compounding amount of the particles contained in the hard coating layer 11, the surface shape of the hard coating layer is adjusted, and an antireflection film having the above-mentioned Sa can be obtained. In addition, the surface shape can also be adjusted by performing a surface treatment such as vacuum plasma treatment on the hard coating layer 11.

When the arithmetic mean height Sa of the surface of the antifouling layer 7 is within the above range, the surface of the hard coat layer 11 also has the same Sa, so the hard coat layer 11 of the antireflection film has excellent adhesion with the antireflection layer 5 and the antifouling layer 7 .

The average spacing RSm of the concave and convex surfaces of the antifouling layer 7 calculated from the roughness curve of the measuring length of 12 mm is preferably 120 μm or more. The RSm of the surface of the antifouling layer 7 is more preferably 130 μm or more, and may be 140 μm or more or 150 μm or more. By making the RSm of the surface of the antireflection film within the above range, the white halo of the reflected light during black display is reduced, and a display with excellent contrast in bright areas can be achieved. The average spacing RSm of the concave and convex surfaces of the antifouling layer 7 is preferably 250 μm or less, more preferably 220 μm or less, further preferably 200 μm or less, and may be 180 μm or less or 170 μm or less.

The arithmetic mean roughness Ra of the surface of the antifouling layer 7 calculated from the roughness curve of the measurement length of 12 mm is preferably 30 to 500 nm, more preferably 50 to 400 nm, further preferably 60 to 300 nm, and may also be 70 to 250 nm or 80 to 200 nm. When the Ra of the surface of the antireflection film is within the above range, there is a tendency to have excellent antiglare properties.

The surface of the antifouling layer 7 easily forms a concavoconvex shape reflecting the surface shape of the hard coating layer 11. Therefore, by adjusting the particle size and compounding amount of the particles contained in the hard coating layer 11, the surface shape of the hard coating layer is adjusted, thereby obtaining an antireflection film having the above-mentioned RSm and Ra.

[Use of anti-reflection film]

The anti-reflection film is used, for example, on the surface of an image display device such as a liquid crystal display or an organic EL display. For example, by configuring the anti-reflection film on the visual recognition side surface of a panel including an image display medium such as a liquid crystal unit or an organic EL unit, the reflection of external light can be reduced and the visual recognition of the image display device can be improved.

The anti-reflection film may be directly bonded to the surface of the image display device or may be laminated with other films. For example, by bonding a polarizer to the hard coat-free surface of the transparent film substrate 10, a polarizing plate with an anti-reflection layer can be formed.

The anti-reflection film having the arithmetic mean height Sa and the average interval RSm of the concavoconvexity on the surface within the above ranges is not prone to white halo of reflected light, has excellent visual recognition, and has excellent adhesion between the hard coating layer 11 and the anti-reflection layer 5 and the anti-fouling layer 7. The image display device having the anti-reflection film has high contrast in bright areas and excellent visual recognition, and is not prone to peeling and abrasion of the anti-reflection layer and the anti-fouling layer, and maintains excellent visual recognition and anti-fouling properties even when the device is used for a long time.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

[Example 1]

＜Production of anti-glare hard coating film＞

(Preparation of Hard Coating Composition)

A 60 wt % dispersion of colloidal silica (nanosilica) having an average primary particle size of 40 nm was added to a urethane acrylate-based photocurable resin composition ("BEAMSET577" manufactured by Arakawa Chemical Industries) so that the amount of silica particles was 40 parts by weight per 100 parts by weight of the resin component. Into 100 parts by weight of the solid content of the solution are mixed 5.0 parts by weight of silicone particles ("Tospearl 130" manufactured by Momentive Performance Materials Japan, with an average particle size of 3.0 μm, a refractive index of 1.43, and a true specific gravity of 1.32); 2.0 parts by weight of an organic montmorillonite as a thixotropic agent ("Sumecton SAN" manufactured by KUNIMINE INDUSTRIES CO., LTD.); 3.0 parts by weight of a photopolymerization initiator ("OMNIRAD 907" manufactured by IGM Resins); and 0.15 parts by weight of a silicone-based leveling agent ("Polyflow LE303" manufactured by Kyoeisha Chemical Co., Ltd.), and the solution is diluted with ethyl acetate to prepare a hard coating composition having a solid content concentration of 30% by weight.

＜Formation of hard coat＞

The hard coating composition was applied to a 60 μm thick triacetyl cellulose (TAC) film ("FUJITAC TG60UL" manufactured by Fujifilm) using a comma coater (registered trademark) and heated at 60°C for 1 minute. Then, the coating layer was cured by irradiating with ultraviolet light at a cumulative light intensity of 300 mJ/ ^cm2 using a high-pressure mercury lamp to form an anti-glare hard coating layer with a thickness of 6.0 μm.

＜Formation of primer layer and anti-reflection layer＞

A triacetylcellulose film with a hard coating layer formed thereon was introduced into a roll-to-roll sputtering film forming apparatus, and while the film was being advanced, the surface of the hard coating layer was bombarded (using Ar gas plasma treatment), and then a 1.5 nm ITO layer was formed as a primer layer, and a 10.1 nm Nb ₂ O ₅ layer, a 27.5 nm SiO ₂ layer, a 105.0 nm Nb ₂ O ₅ layer, and an 83.5 nm SiO ₂ layer were sequentially formed thereon. A Si target was used for the formation of the primer layer and the SiO ₂ layer, and a Nb target was used for the formation of the Nb ₂ O ₅ layer. In the formation of the SiO ₂ layer and the Nb ₂ O ₅ layer, the amount of oxygen introduced was adjusted by plasma emission monitoring (PEM) control so that the film formation mode maintained the transition region.

＜Formation of antifouling layer＞

An antifouling coating agent containing a perfluoropolyether group-containing alkoxysilane compound and having a solid content concentration of 20% ("KY1903-1" manufactured by Shin-Etsu Chemical Co., Ltd.) was dried and cured as a deposition source, and an antifouling layer having a thickness of 8 nm was formed on the antireflection layer by vacuum deposition at a heating temperature of 260°C.

[Example 2, Comparative Examples 1 to 5]

In the preparation of the hard coating composition, the type and amount of micronized particles, and the particle size and amount of silica particles were changed as shown in Table 1. The preparation of the anti-glare hard coating film, the formation of the primer layer and the anti-reflection layer, and the formation of the anti-fouling layer were carried out in the same manner as in Example 1. In Comparative Example 2, cross-linked polymethyl methacrylate (PMMA) particles ("Technopolymer SSX-103" manufactured by Sekisui Chemicals; average particle size 3.0 μm, refractive index 1.50, specific gravity 1.20) were used as micronized particles. In Comparative Examples 3 to 5, silicone particles and cross-linked PMMA particles were used in combination as micronized particles.

[evaluate]

<Measurement of surface shape>

A 1.3 mm thick slide glass ("MICRO SLIDE GLASS" 45 x 50 mm manufactured by MATSUNAMI) was bonded to the triacetylcellulose film side of the antireflection film (antireflection layer non-formed side) via a 20 μm thick acrylic adhesive to prepare a measurement sample.

The roughness curve of the surface of the antifouling layer was measured under the following conditions using a stylus-type surface roughness measuring instrument (“Surfcorder ET4000”, a high-precision fine shape measuring instrument manufactured by Kosaka Laboratory) having a measuring needle with a curvature radius R=2 μm at the tip (diamond), and the arithmetic mean roughness Ra and the average length RSm of the roughness curve elements were determined in accordance with JIS B0601:2001.

Scanning speed: 0.1mm/sec

Measuring length: 12mm

Cut-off value: 0.8mm

The three-dimensional surface properties of the antifouling layer surface were measured under the following conditions using an atomic force microscope ("Dimemsion 3100" manufactured by Bruker, controller: Nanoscope V), and the arithmetic mean height Sa was calculated in accordance with ISO 25178.

Measurement mode: tapping mode

Cantilever: Si single crystal

Measuring field of view: 1μm×1μm

＜Reflection Visibility＞

A black acrylic plate was attached to the triacetylcellulose film side of the anti-reflection film (the non-anti-reflection layer forming side) with the aid of a 20 μm thick acrylic adhesive. The anti-reflection film side of the sample was irradiated with light from a desk lamp at an illumination of 1000 lux from a distance of 30 cm, and the reflected light from the anti-reflection film was visually confirmed. The case where the peripheral area of the regular reflected light was visually identified as black (refer to "Example 1" in Figure 2) was set to 0, and the case where the entire area was visually identified as a white halo (refer to "Comparative Example 2" in Figure 2) was set to ×.

＜Adhesion＞

A glass plate with a thickness of 1.3 mm was adhered to the triacetylcellulose film side of the anti-reflection film (the surface on which the anti-reflection layer is not formed) via a 25 μm thick acrylic adhesive, and the sample was put into an accelerated weathering tester "EYESUPERUV TESTER SUV-W161" manufactured by Iwasaki Electric, and an accelerated weathering test was carried out for 120 hours under the conditions of a black panel temperature of 80°C and an irradiation intensity of a metal halide lamp of 150 mW/ ^cm2 .

The surface of the antifouling layer side of the sample after the accelerated weathering test was scratched at 1 mm intervals to form a 100-square grid, and the adhesion test was carried out according to the cross-cut test method (coating adhesion test) of JIS K 5400 8.5: 1990. The number of squares where the antifouling layer and the antireflection layer peeled off in an area of more than 1/4 of the square area was counted. The case where the number of peeled squares was 10 or more was set to ×, and the case where the number of squares was less than 9 was set to 0.

[Evaluation results]

The composition of the hard coat layer of the antireflection film of the above-mentioned Example and Comparative Example (the type of microparticles of the hard coat layer and the amount thereof blended relative to 100 parts by weight of the binder resin) and the evaluation results of the antireflection film are shown in Table 1. Observation photographs of reflected light of the antireflection film of Example 1 and Comparative Example 2 are shown in FIG.

[Table 1]

In Example 1, in which 5 parts by weight of organic silicon particles are mixed as micron particles and 40 parts by weight of silica particles with a particle size of 40 nm are mixed as nanoparticles, the hard coating layer has high adhesion to the anti-reflection layer and the antifouling layer, and has good visual recognition without white halo of reflected light. The same is true for Example 2 in which the mixing amount of nano silica particles is changed to 30 parts by weight. In Comparative Example 1 in which 40 parts by weight of silica particles with a particle size of 10 nm are mixed as nanoparticles, Sa is small and the adhesion of the hard coating layer to the anti-reflection layer and the antifouling layer is insufficient.

In Comparative Example 4, in which 3 parts by weight of silicone particles and 1 part by weight of PMMA particles were blended as micron particles, and 20 parts by weight of silica particles with a particle size of 40 nm were blended as nanoparticles, Sa was small, and the adhesion was insufficient as in Comparative Example 1. In Comparative Example 5, in which the amount of nanoparticles was changed to 10 parts by weight, Sa was even smaller than in Comparative Example 4, and the adhesion was insufficient.

It is considered that since the particle size of the nanoparticles in Comparative Example 1 was small and the amount of the nanoparticles in Comparative Examples 4 and 5 was small, nanoscale irregularities were not sufficiently formed on the surface of the hard coat layer, and the adhesion was inferior to that of Examples 1 and 2.

In Comparative Example 2, in which 15 parts by weight of PMMA particles were blended as microparticles and 40 parts by weight of silica particles having a particle size of 40 nm were blended as nanoparticles, the adhesion between the hard coating layer and the antireflection layer and the antifouling layer was good, but a white halo was observed in the reflected light, and the visual recognition was poor compared with Examples 1 and 2. In Comparative Example 2, since the amount of microparticles was large, the in-plane density of the microparticles in the hard coating layer was high, and the average interval RSm of the concavoconvexities was small, which is considered to be the main cause of the white halo of the reflected light.

Comparative Example 3, in which 3 parts by weight of silicone particles and 1 part by weight of PMMA particles are mixed as micron particles, also observed white halo in reflected light in the same manner as in Comparative Example 2. In Comparative Example 3, as in Comparative Example 2, it is believed that the small RSm is the main cause of the white halo. In Comparative Example 3, the mixing of micron particles is the same as in Comparative Examples 4 and 5. Although the amount of micron particles is less than that of Examples 1 and 2, the average interval RSm of the concave and convex becomes smaller. It is believed that in Comparative Example 3, PMMA particles with a relatively small specific gravity are easily present near the surface of the hard coating layer, and near the surface of the hard coating layer, PMMA micron particles and nano-silica particles are dense, so RSm becomes smaller.

From the comparison between the above-mentioned embodiments and the comparative examples, it can be seen that by having both micron particles and nanoparticles in the hard coating layer, adjusting the type, particle size, and blending amount of these particles, increasing the index of surface roughness at the nm scale, namely Sa, and increasing the index of the roughness period at the μm scale, namely RSm, it is possible to obtain an anti-reflection film having excellent adhesion between the hard coating layer and the anti-reflection layer and the anti-fouling layer, less white halo of reflected light, and excellent visual recognition.

Claims (10)

1. An antireflection film, comprising: a hard coat film comprising a hard coat layer on one main surface of a transparent film base material, and an antireflection layer and an antifouling layer provided in this order on the hard coat layer,

The antireflection layer is formed of a laminate of a plurality of films having different refractive indices,

The hard coat layer comprises a binder resin, microparticles having an average particle diameter of 1 to 8 [ mu ] m, and nanoparticles having an average primary particle diameter of 100nm or less,

The average interval RSm of the irregularities calculated according to JIS B0601 from a roughness curve of a measurement length of 12mm of the stain-proofing layer measured by a stylus method is 120 μm or more,

The arithmetic mean height Sa calculated according to ISO 25178 from the three-dimensional surface properties of a1 [ mu ] m by 1 [ mu ] m region of the antifouling layer measured by an atomic force microscope is 2.0nm or more.

2. The antireflection film according to claim 1, wherein the specific gravity of the microparticles is 1.25 or more.

3. The antireflection film according to claim 2, wherein the amount of particles having a specific gravity of 1.25 or more is 85 parts by weight or more in 100 parts by weight in total of the microparticles.

4. The antireflection film according to any one of claims 1 to 3, wherein the amount of the microparticles in the hard coat layer is 0.5 to 12 parts by weight relative to 100 parts by weight of the binder resin.

5. The antireflection film according to any one of claims 1 to 3, wherein the amount of the nanoparticles in the hard coat layer is 25 to 120 parts by weight relative to 100 parts by weight of the binder resin.

6. The antireflection film according to any one of claims 1 to 3, wherein the nanoparticles have an average primary particle diameter of 15nm or more.

7. The antireflection film according to any one of claims 1 to 3, wherein an arithmetic average roughness Ra calculated from a roughness curve of a measured length of 12mm of the stain-proofing layer measured by a stylus method according to JIS B0601 is 30 to 500nm.

8. The antireflection film according to any one of claims 1 to 3, wherein the antireflection layer is a sputtered film.

9. The antireflection film according to any one of claims 1 to 3, wherein a primer layer formed of an inorganic oxide is provided between the hard coat layer and the antireflection layer.

10. An image display device provided with the antireflection film according to any one of claims 1 to 9 on a visual recognition side surface of an image display medium.