TW202436092A - Anti-reflection film and image display device - Google Patents

Abstract

The anti-reflection film (101) of the present invention comprises an anti-reflection layer (5) and an anti-fouling layer (7) sequentially arranged on a hard coating layer (11) of a hard coating film (1) having a hard coating layer (11) on one main surface of a transparent film substrate (10). The hard coating layer comprises a binder resin, micron particles with an average primary particle size of 1 to 8 μm, and nanoparticles with an average primary particle size of less than 100 nm. The anti-reflection layer comprises a laminate of a plurality of thin films with different refractive indices. The average interval RSm of the concavities and convexities of the anti-reflection film obtained from a roughness curve with 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 area is greater than 2.0 nm.

Description

Anti-reflection film and image display device

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

Anti-reflection film is used on the viewing side surface of image display devices such as liquid crystal displays or organic EL displays to prevent image quality degradation caused by reflection of external light and to improve contrast. The anti-reflection film has an anti-reflection layer composed of a laminate of multiple thin films with different refractive indices on a transparent film.

In order to prevent the contrast from being reduced due to the reflection of external light, there is a method of implementing antiglare treatment. For example, in patent documents 1 to 3, an antiglare anti-reflection film is disclosed, in which an anti-reflection layer is provided on an antiglare hard coating film having a hard coating layer containing microparticles formed on a transparent film. The antiglare anti-reflection film forms surface irregularities by making the hard coating layer contain microparticles (micrometer particles) with a particle size of μm order, so that external light is scattered and reflected, thereby reducing the reflection 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 states that the light diffusion of the surface is improved by agglomerating silica particles with an average primary particle size of 20 nm to form amorphous secondary particles. Patent document 2 states that the surface-modified nanosilica particles have the function of inhibiting the precipitation of organic microparticles (micron particles) and making them float to the surface, so that the anti-glare property can be adjusted. Patent document 3 (refer to Examples 6 to 8) states that the anti-glare hard coating layer contains nanosilica particles, thereby forming fine concave and convex on the surface of the hard coating layer, 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 Publication No. 2008-40064 [Patent Document 2] Japanese Patent Publication No. 2009-204728 [Patent Document 3] International Publication No. 2021/106797

[The problem the invention is trying to solve]

Previous anti-glare anti-reflection films had the following problems: the adhesion between the hard coating layer and the anti-reflection layer was low, and if exposed to external light for a long time, the anti-reflection layer (and the anti-fouling layer disposed thereon) would easily peel off, and with use, the optical properties or anti-fouling properties would deteriorate.

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

In view of the above situation, the purpose of the present invention is to provide an anti-reflection film with high adhesion between the anti-glare hard coating layer and the anti-reflection layer, less halo of reflected light, and good visibility. [Technical means to solve the problem]

The anti-reflection film of the present invention has an anti-reflection layer and an anti-fouling layer sequentially disposed on a hard coating layer of a hard coating film having a hard coating layer on one main surface of a transparent film substrate. The hard coating layer contains a binder, microparticles (micron particles) with a particle size of 1 to 8 μm, and microparticles (nanoparticles) with an average primary particle size of less than 100 nm.

The anti-reflection layer comprises a laminate of a plurality of thin films having different refractive indices. The thin film constituting the anti-reflection layer is preferably an inorganic oxide. The anti-reflection layer may be a sputtered film formed by sputtering. A primer layer comprising an inorganic oxide may be disposed between the hard coating layer and the anti-reflection layer.

The surface of the anti-reflection film (the surface of the anti-fouling layer) preferably has an average interval RSm of 120 μm or more obtained from a roughness curve with a measured length of 12 mm, and preferably has an arithmetic mean height Sa of 2.0 nm or more obtained from the three-dimensional surface properties of a 1 μm×1 μm area. The arithmetic mean roughness Ra of the surface of the anti-reflection film obtained from a roughness curve with a measured length of 12 mm can also be 30~500 nm.

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

The amount of micron particles in the hard coating layer is preferably 0.5 to 12 parts by weight relative to 100 parts by weight of the adhesive resin. The amount of nanoparticles in the hard coating layer is preferably 25 to 120 parts by weight relative to 100 parts by weight of the adhesive. The average primary particle size of the nanoparticles is preferably greater than 15 nm. [Effects of the invention]

The hard coating layer of the anti-reflection film with Sa and RSm mentioned above has a higher adhesion with the anti-reflection layer, exhibits a higher anti-glare property, and has less halo of reflected light, which has good visibility. The image display device with the anti-reflection film disposed on the visual side surface of the image display medium shows excellent anti-glare property, high contrast in bright areas, and the anti-reflection layer and anti-fouling layer are difficult to peel off, so it can maintain excellent optical characteristics and anti-fouling properties even after long-term use.

FIG1 is a cross-sectional view showing an example of a laminated structure of an antireflection film according to an embodiment of the present invention. The antireflection film 101 has an antireflection layer 5 on a hard coating layer 11 of a hard coating film 1, and an antifouling layer 7 on the antireflection layer 5. The hard coating film 1 has a hard coating layer 11 on one main surface of a transparent film substrate 10. The antireflection 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 antireflection layer 5.

[Hard coating film] The hard coating film 1 has a hard coating layer 11 on one main surface of a transparent film substrate 10. By providing the hard coating layer 11 on the side where the anti-reflection layer 5 is formed, the mechanical properties such as the surface hardness or scratch resistance of the anti-reflection film can be improved.

<Transparent film substrate> The visible light transmittance of the transparent film substrate 10 is preferably 80% or more, and 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 resin materials include cellulose resins such as triacetyl cellulose, polyester resins, polyether sulfone 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, workability such as handling, and thinness.

<Hard coating layer> 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 includes a binder resin and fine particles, and the fine particles include micron particles 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 by utilizing the surface roughness formed by the micron particles, and the fine surface roughness 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 higher 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, if the thickness of the hard coating layer 11 is too large, the surface unevenness of the hard coating layer may not be properly formed, or the film strength may be reduced due to coagulation 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 setting the ratio of the particle size of the micronized particles to the thickness of the hard coating layer within the above range, the concavo-convex shape formed on the surface of the hard coating layer can easily become one with excellent anti-glare properties.

The haze of the hard coating is preferably 1-35%, more preferably 2-30%, and may also be 3-25%, 4-20%, 5-17%, or 6-15%. If the haze of the hard coating is within the above range, both anti-glare and image clarity can be taken into account. When the haze is too small, the anti-glare property may be poor, and when the haze is too large, the scattering of the transmitted light is large, and the image clarity tends to be reduced.

The arithmetic mean height Sa calculated from the three-dimensional surface properties of the 1 μm×1 μm area of the surface 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 measured length of 12 mm on the surface of the hard coating layer 11 is preferably 120 μm or more.

The arithmetic mean height Sa is a value calculated according to ISO 25178 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 concavo-convex on the nm scale. The larger the arithmetic mean height Sa of the hard coating layer 11, the higher the adhesion of the anti-reflection layer 5 tends to be. The larger the particle size of the nanoparticles contained in the hard coating layer 11 and the higher the content of the nanoparticles, the larger Sa tends to be. The arithmetic mean height Sa of the hard coating layer 11 is preferably 2.3 nm or more, and 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, if the surface unevenness formed by the nanoparticles becomes coarse, sufficient adhesion may not be achieved. In addition, if the surface unevenness formed by the nanoparticles becomes large, the shape of the micronized particles is difficult to reflect on the surface shape of the hard coating layer 11, and the anti-glare property is reduced. Therefore, the arithmetic mean height Sa of the hard coating layer 11 is preferably 10 nm or less, more preferably 8.0 nm or less, and further preferably 7.0 nm or less, and may also be 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, or 4.5 nm or less.

The average interval RSm of the concave and convex is a roughness curve obtained by passing a cross-sectional curve of 12 mm in length measured by a stylus-type surface roughness tester through a wide-area filter with a cutoff value of 0.8 mm. It is the average length of the roughness curve element calculated in accordance with JIS B0601:2001 and is an index indicating the surface density of the concave and convex on the μm scale. The smaller the average interval RSm of the concave and convex of the hard coating layer 11 is, the higher the density of the concave and convex formed on the surface of the hard coating layer by micron particles is, and the better the anti-glare property tends to be. On the other hand, if RSm is too small, when the image display device is in black display, 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 tends to decrease (refer to "Comparison Example 2" in Figure 2).

By making the average interval RSm of the concavoconvexity of the hard coating layer 11 120 μm or more, the density of black is good, and a display with high contrast in bright areas can be achieved. The average interval RSm of the concavoconvexity of the hard coating 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, if the average interval RSm of the concavoconvexity 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 concavoconvexity 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 roughness curve of the surface of the hard coating layer 11 obtained by measuring a cross-sectional curve of 12 mm in length through a wide-area filter with a cutoff value of 0.8 mm is preferably 30 to 500 nm in arithmetic average roughness Ra calculated in accordance with JIS B0601:2001. The arithmetic average roughness Ra is an indicator of the degree of formation of sub-micron to μm-scale high concavities and convexities that contribute to light scattering. There is a tendency that the larger the particle size of the micron particles contained in the hard coating layer 11 and the more the content of the micron particles, the larger the Sa.

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

The composition used to form the hard coating layer 11 includes a binder resin (or a curable resin as a precursor thereof), micron particles having a particle size of 1 μm or more, and nanoparticles having a particle size of 100 nm or less.

(Adhesive resin) As the adhesive resin of the hard coating layer 11, it is preferable to use a curable resin such as a thermosetting resin, a light curing resin, an electron beam curing resin, etc. Examples of the curable resin include polyester series, acrylic series, urethane series, acryl urethane series, amide series, polysilicone series, silicate series, epoxy series, melamine series, cyclohexane series, acrylate urethane series, etc. Among them, acrylic resin, acrylamide resin and epoxy resin are preferred in terms of higher hardness and ability to be photocured, among which acrylic resin and acrylamide resin are preferred. The refractive index of adhesive resin is generally around 1.4~1.6.

The photocurable adhesive resin component includes a multifunctional compound having two or more photopolymerizable (preferably UV-polymerizable) functional groups. The multifunctional compound may be a monomer or an oligomer. As the photopolymerizable multifunctional compound, a compound having two or more (meth)acrylic groups in one molecule (multifunctional (meth)acrylate) is preferably used.

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

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

As materials for micronized 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 of various transparent polymers such as polymethyl methacrylate, polystyrene, polyurethane, acrylic resin-styrene copolymer, benzoguanamine, melamine, polycarbonate, polysilicone, etc. can be used without particular limitation. One or more of these particles can be appropriately selected for use. It is possible to produce particles with a particle size of μm level and a relatively small length diameter, and a relatively high uniformity of the particle size, and in terms of high density, polysilicone is particularly preferred as a material for micronized particles.

It is preferred that the refractive index difference between the micron particles and the binder resin of the hard coating layer is smaller. By reducing the refractive index difference between the binder and the micron particles, light scattering at the interface between the binder resin and the micron particles is reduced, and the haze is reduced, so that a display with a higher sense of transparency can be achieved. On the other hand, when the haze of the hard coating layer is too small, the anti-glare property may become insufficient. From the perspective of making the hard coating layer have an appropriate haze and achieving a display with a higher sense of transparency, 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 can be 1.30 or more. The specific gravity of the micron particles can 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 are easily precipitated and tend to be close to the transparent film substrate 10. As a result, the nanoparticles tend to be close to the surface of the hard coating layer 11 (the interface with the anti-reflection layer 5 or the primer layer 3), and fine concavities and convexities are uniformly formed in the surface, so there is a tendency to improve the adhesion of the anti-reflection layer.

In the case where micron particles and nanoparticles coexist in the hard coating layer 11, if 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 the contrast of the bright area tends to decrease due to the halo of the reflected light. By using micron particles with a large specific gravity and easy precipitation, there is a tendency that the interval of the concavities and convexities formed on the surface of the hard coating layer becomes larger due to the shape of the micron particles, and RSm tends to increase.

When the hard coating layer contains two or more types of micron particles, 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 1.25 or more, when the ratio of micron particles with a specific gravity less than 1.25 is large, the amount of micron particles present near the surface of the hard coating layer increases and the RSm of the hard coating layer tends to decrease. Therefore, out of a total of 100 parts by weight of micron particles, the amount of particles with a specific gravity of 1.25 or more is preferably 85 parts by weight or more, more preferably 90 parts by weight or more, and may also be 95 parts by weight or more, 99 parts by weight or more, or 100 parts by weight.

The content of micron particles in the hard coating layer is not particularly limited. From the viewpoint of uniformly forming unevenness on the surface of the hard coating 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 adhesive resin. When the content of micron particles is small, the RSm of the hard coating layer may be large and the anti-glare property may be 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 small and the contrast in bright areas to decrease due to the halo of reflected light.

As described above, by adjusting the specific gravity, particle size, and content of the micron particles, the surface shape of the hard coating layer 11 can be adjusted to impart anti-glare properties and reduce halo. The greater the content of the micron particles, the greater the number of convex portions formed by the micron particles, and therefore there is a tendency for RSm to decrease. In addition, there is a tendency for Ra to increase as the average particle size of the micron particles increases and the content of the micron particles increases. When the specific gravity of the micron particles is smaller and the ratio of the micron particles present near the surface is greater, there is a tendency for RSm to decrease and Ra to increase.

(Nano particles) The hard coating layer 11 contains nano particles with a particle size of 100 nm or less in addition to micro particles with a particle size of 1 μm or more, thereby forming fine concavities and convexities smaller in size than those formed by micro particles on the surface of the hard coating layer, and there is a tendency to improve the adhesion between the hard coating layer 11 and the anti-reflection layer 5 formed thereon.

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, niobium oxide, and magnesium oxide can be cited. The inorganic oxide can be a composite oxide of multiple (semi) metals. Among the inorganic oxides exemplified, silicon oxide is preferred in terms of low refractive index, excellent transparency, and high adhesion improvement effect. Among them, colloidal silicon dioxide is particularly preferred as the material of nanoparticles in terms of being able to produce microparticles with high uniformity of particle size, excellent dispersibility, and low density. In order to improve the affinity with the adhesive resin or to increase the hardness of the hard coating layer, functional groups such as acryl and epoxy groups can also be introduced into the surface of the nanoparticles.

The specific gravity of nanoparticles is preferably smaller than that of micron particles. By making the specific gravity of nanoparticles relatively low, the nanoparticles are easily biased near the surface of the hard coating layer 11, and fine concavoconvexities are uniformly formed in the surface, so that the adhesion of the anti-reflection layer tends to be improved. The specific gravity of nanoparticles is preferably less than 1.25, and can be less than 1.23 or less than 1.21. The specific gravity of 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 accordingly, the adhesion of the anti-reflection layer 5 tends to be improved.

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

The content of nanoparticles in the hard coating layer is not particularly limited. From the perspective of increasing the Sa of the hard coating layer and improving 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 adhesive resin, and can also 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 coating layer becomes smaller, and it is easy to produce halo of reflected light. Therefore, the content of nanoparticles in the hard coating layer 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 adhesive resin. It can also 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 coating layer) The hard coating composition comprises the above-mentioned binder resin component, microparticles and nanoparticles, and optionally a solvent. When the binder resin component is a curable resin, the composition preferably contains a suitable polymerization initiator. For example, when the binder resin component is a photocurable resin, the composition preferably contains a photopolymerization initiator.

In addition to the above, the hard coating composition may also contain additives such as leveling agents, viscosity modifiers (thickening agents, etc.), antistatic agents, anti-adhesion agents, dispersants, dispersion stabilizers, antioxidants, ultraviolet absorbers, defoaming agents, surfactants, lubricants, etc.

As the activator, organic clay, oxidized polyolefin, modified urea, etc. can be cited. Among them, organic clay such as bentonite is preferred. The amount of the activator to be prepared is preferably about 0.3 to 5 parts by weight relative to 100 parts by weight of the adhesive. As the leveling agent, for example, fluorine-based or polysilicone-based leveling agents can be cited, and the amount of the leveling agent to be prepared is preferably about 0.01 to 3 parts by weight relative to 100 parts by weight of the adhesive.

The hard coating composition is applied onto a transparent film substrate 10, and the solvent is removed and the resin is cured as needed to form a hard coating layer 11.

As a coating method of the hard coating composition, any appropriate method such as rod coating, roller coating, gravure coating, rod coating, hole coating, curtain coating, spray coating, and notch wheel coating 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 adhesive resin component is a photocurable resin, light curing 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, the hard coating layer 11 may be subjected to surface treatment for the purpose of further improving the adhesion between the hard coating layer 11 and the anti-reflection layer 5. Examples of the surface treatment include surface modification treatments such as corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, radiant treatment, alkali treatment, acid treatment, and treatment using a coupling agent. As the surface treatment, vacuum plasma treatment may be performed. In dry etching treatment using vacuum plasma or the like, the resin component on the hard coating surface is easily selectively etched, and the existence ratio of nanoparticles on the hard coating surface and in the vicinity thereof becomes higher, so there is a tendency for the arithmetic mean height Sa of the hard coating surface to become larger.

[Anti-reflection film] Anti-reflection layer 5 is formed on hard coating layer 11 of hard coating film 1 via primer layer 3 as needed, and anti-fouling layer 7 is formed on anti-reflection layer 5, thereby obtaining an anti-reflection film.

<Undercoat layer> It is preferred to provide an undercoat layer 3 between the hard coat layer 11 and the anti-reflection layer 5. Examples of the material of the undercoat layer 3 include metals such as silicon, nickel, chromium, tin, gold, silver, platinum, zinc, titanium, indium, tungsten, aluminum, zirconium, and palladium; alloys of these metals; oxides, fluorides, sulfides, or nitrides of these metals; and the like. Among them, the material of the undercoat layer is preferably an inorganic oxide, particularly preferably silicon oxide or indium oxide. The inorganic oxide constituting the undercoat layer 3 may also be a composite oxide such as indium tin oxide (ITO).

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

The thickness of the primer layer 3 is, for example, about 1 to 20 nm, preferably 3 to 15 nm. If the thickness of the primer layer is within the above range, both the adhesion with the hard coating layer 11 and the high light transmittance can be taken into consideration.

<Anti-reflection layer> The anti-reflection layer 5 is formed of 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 reversed phases of the incident light and the reflected light cancel each other out. By making the anti-reflection layer into a multi-layered body 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 constituting the thin film of the anti-reflection layer 5, metal oxides, nitrides, fluorides, etc. can be cited. The anti-reflection layer 5 is preferably an alternating layer of high refractive index layers and low refractive index layers. In order to reduce 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), etc. 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, tantalum fluoride, and tantalum fluoride. Among them, silicon oxide is preferred. Particularly preferably, _Nb2O5 thin films 51 and ₃₃ as high refractive index layers and _SiO2 thin films 52 and 54 as low refractive index layers are alternately laminated. In addition to the low refractive index layers and the high refractive index layers, a medium refractive index layer having a refractive index of about 1.6 to 1.9 may also be provided.

The 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 thickness of each layer can be designed in such a way that the reflectivity of visible light becomes smaller according to the refractive index or the layered structure. For example, as a layered structure of the high refractive index layer and the low refractive index layer, there can be cited a four-layer structure from the hard coating side, which is 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.

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

In the sputtering method, a long strip of hard coating film can be transported in one direction (lengthwise) by a roll-to-roll method while continuously forming a thin film. In the sputtering method, an inert gas such as argon and a reactive gas such as oxygen as needed are introduced into a chamber while film formation is performed. The formation of an oxide layer by sputtering can be performed by either a method using an oxide target or 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 preferred.

<Antifouling layer> The antireflection film has an antifouling layer 7 as the outermost layer (top coating) on the antireflection layer 5. By providing the antifouling layer on the outermost surface, the influence of pollution (fingerprints, hand dirt, dust, etc.) from the external environment can be reduced, and pollutants attached to the surface can be easily removed.

In order to maintain the antireflection property of the antireflection layer 5, the antifouling layer 7 preferably has a smaller refractive index difference than 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 also contribute to lowering the refractive index. Among them, from the perspective of excellent water repellency and the ability to exert higher antifouling properties, a fluorine-based polymer containing a perfluoropolyether skeleton is preferred. From the perspective of improving antifouling properties, a perfluoropolyether having a main chain structure that can be arranged rigidly is particularly preferred. As the structural unit of the main chain skeleton of perfluoropolyether, perfluoroalkylene oxide having a branched chain of 1 to 4 carbon atoms is preferred, for example, perfluoromethylene oxide ( _-CF2O- ), perfluoroethylene oxide ( _-CF2CF2O- ), _{perfluoropropylene} oxide (-CF2CF2CF2O-), _{perfluoroisopropylene} oxide (-CF _{( CF3 ) CF2O-} ), etc.

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

In order to improve the anti-pollution property and the removal property of pollutants, the water contact angle of the anti-pollution 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 removal property of pollutants. 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 anti-reflection film, i.e., the surface of the anti-fouling layer 7, calculated from the three-dimensional surface properties of the area of 1 μm×1 μm is preferably 2.0 nm or more. The arithmetic mean height Sa of the surface of the anti-fouling layer 7 is more preferably 2.3 nm or more, and 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. The arithmetic mean height Sa of the surface of the anti-fouling layer 7 is preferably 10 nm or less, more preferably 8.0 nm or less, and further preferably 7.0 nm or less, and may also be 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, or 4.5 nm or less.

Since the thickness of the antireflection layer 5 and the antifouling layer 7 formed on the hard coating layer 11 is small, 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 or the amount of particles contained in the hard coating layer 11 to adjust the surface shape of the hard coating layer, 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 coating layer 11 also has the same Sa, so the hard coating layer 11 of the antireflection film has excellent adhesion with the antireflection layer 5 and the antifouling layer 7.

The average interval RSm of the concavities and convexities on the surface of the antifouling layer 7 calculated from the roughness curve of the measured 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 halo of the reflected light during black display is reduced, and a display with excellent contrast in bright areas can be achieved. The average interval RSm of the concavities and convexities on the surface of the antifouling layer 7 is preferably 250 μm or less, more preferably 220 μm or less, and 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 measured length of 12 mm is preferably 30-500 nm, more preferably 50-400 nm, further preferably 60-300 nm, and may also be 70-250 nm or 80-200 nm. When the Ra of the surface of the antireflection film is within the above range, it tends to have excellent anti-glare properties.

The surface of the antifouling layer 7 easily forms an uneven shape reflecting the surface shape of the hard coating layer 11. Therefore, by adjusting the particle size or the amount of particles contained in the hard coating layer 11 to adjust the surface shape of the hard coating layer, an antireflection film having the above-mentioned RSm and Ra can be obtained.

[Use of anti-reflection film] Anti-reflection film is used on the surface of image display devices such as liquid crystal display or organic EL display. For example, by configuring an anti-reflection film on the viewing side surface of a panel containing image display media such as liquid crystal unit or organic EL unit, the reflection of external light can be reduced and the visibility of the image display device can be improved.

The anti-reflection film can be directly attached to the surface of the image display device, or can be laminated with other films. For example, by attaching a polarizer to the surface of the transparent film substrate 10 where the hard coating layer is not formed, a polarizing plate with an anti-reflection layer can be formed.

The anti-reflection film with the arithmetic mean height Sa of the surface and the average interval RSm of the concave and convex in the above range is not easy to produce halo of reflected light, has excellent visibility, and the hard coating layer 11 has excellent adhesion with the anti-reflection layer 5 and the anti-fouling layer 7. The image display device with the anti-reflection film has a high contrast in bright areas and excellent visibility, and it is not easy to produce peeling or wear of the anti-reflection layer and the anti-fouling layer. Even when the device is used for a long time, it still maintains excellent visibility and anti-fouling properties. [Example]

The present invention is described in more detail below with reference to the following embodiments, but the present invention is not limited to the following embodiments.

[Example 1] <Preparation 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 ("BEAMSET 577" manufactured by Arakawa Chemical Industries) in such a manner that the amount of silica particles was 40 parts by weight relative to 100 parts by weight of the resin component. 5.0 parts by weight of polysilicone particles ("Tospearl 130" manufactured by Momentive Performance Materials Japan, average particle size 3.0 μm, refractive index 1.43, true specific gravity 1.32), 2.0 parts by weight of organic expanded stone ("Sumecton SAN" manufactured by KUNIMINE INDUSTRIES CO., LTD.) as a thixotropic agent, 3.0 parts by weight of a photopolymerization initiator ("OMNIRAD 907" manufactured by IGM Resins), and 0.15 parts by weight of a polysilicone leveling agent ("Polyflow LE303" manufactured by Kyoeisha Chemical) were mixed with 100 parts by weight of the solid content of the solution, and diluted with ethyl acetate to prepare a hard coating composition with a solid content concentration of 30% by weight.

<Formation of hard coating layer> The above hard coating composition was applied to a 60 μm thick triacetyl cellulose (TAC) film ("FUJITAC TG60UL" manufactured by Fuji Film) using Comma Coater (registered trademark) and heated at 60°C for 1 minute. Then, the coated 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> The triacetyl cellulose film with hard coating layer formed was introduced into a roll-to-roll sputtering film forming device. While the film was being moved, the surface of the hard coating layer was bombarded (using argon plasma treatment), and then a 1.5 nm ITO layer was formed as a primer layer. 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. Si targets were used for the formation of the primer layer and SiO ₂ layer, and Nb targets were 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 in such a way that the transition region was maintained in the film formation mode.

<Formation of antifouling layer> Antifouling coating agent containing alkoxysilane compound containing perfluoropolyether group with a solid content concentration of 20% ("KY1903-1" manufactured by Shin-Etsu Chemical Co., Ltd.) was dried and solidified as an evaporation source, and an antifouling layer with a thickness of 8 nm was formed on the antireflection layer by vacuum evaporation 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. Otherwise, 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 antifouling 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 Co., Ltd.; 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, polysilicone particles and cross-linked PMMA particles were used in combination as micronized particles.

[Evaluation] ＜Measurement of surface shape＞ A 1.3 mm thick slide glass ("MICRO SLIDE GLASS" 45×50 mm manufactured by MATSUNAMI) was bonded to the triacetyl cellulose film side of the anti-reflection film (the side without the anti-reflection layer) via a 20 μm thick acrylic adhesive to prepare a sample for measurement.

Using a stylus surface roughness tester (Kosaka Laboratory, high-precision fine shape tester "Surfcorder ET4000") with a tip (diamond) having a curvature radius of R = 2 μm, the roughness curve of the antifouling layer surface was measured under the following conditions, and the arithmetic mean roughness Ra and the average length RSm of the roughness curve element were calculated in accordance with JIS B0601: 2001. Scanning speed: 0.1 mm/sec Measuring length: 12 mm Cutoff value: 0.8 mm

Using an atomic force microscope ("Dimemsion 3100" manufactured by Bruker, controller: Nanoscope V), the three-dimensional surface properties of the antifouling layer were measured under the following conditions, and the arithmetic mean height Sa was calculated in accordance with ISO 25178. Measurement mode: Tapping mode Cantilever: Si single crystal Measurement field: 1 μm×1 μm

<Reflection visibility> A black acrylic resin plate was bonded to the triacetyl cellulose film side of the anti-reflection film (the side without the anti-reflection layer) via a 20 μm thick acrylic adhesive. The anti-reflection film side of the sample was illuminated with 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 area around the positive reflected light that was perceived as black (refer to "Example 1" in Figure 2) was set as ○, and the area that was perceived as white as a whole (refer to "Comparative Example 2" in Figure 2) was set as ×.

<Adhesion> A 1.3 mm thick glass plate was bonded to the triacetyl cellulose film side of the anti-reflection film (the side without the anti-reflection layer) via a 25 μm thick acrylic adhesive. The sample was placed in the "EYESUPER UV TESTER SUV-W161" weathering acceleration tester manufactured by Iwasaki Electric Co., Ltd., and an accelerated weathering test was carried out for 120 hours under the conditions of a black panel temperature of 80°C and a metal halide lamp irradiation intensity of 150 mW/ ^cm2 .

The surface of the antifouling layer of the sample after the accelerated weathering test is cut into 100 squares at intervals of 1 mm, and the adhesion test is carried out according to the grid test method (coating adhesion test) of JIS K 5400 8.5:1990. The number of squares peeled off from the antifouling layer and the anti-reflection layer in an area of more than 1/4 of the square area is counted. The case where the number of peeled squares is more than 10 is set as ×, and the case where the number of peeled squares is less than 9 is set as ○.

[Evaluation Results] The composition of the hard coating layer of the anti-reflection film of the above-mentioned embodiment and comparative example (the type of microparticles of the hard coating layer and the amount thereof formulated relative to 100 parts by weight of the binder resin) and the evaluation results of the anti-reflection film are shown in Table 1. The observation photographs of the reflected light of the anti-reflection film of embodiment 1 and comparative example 2 are shown in Figure 2.

[Table 1] Hard coating Anti-reflective film Micron particles Nanoparticles Surface shape Reflection Visibility Adhesion Material proportion Particle size (μm) Mixing amount (weight parts) Particle size (nm) Mixing amount (weight parts) Sa (nm) Ra (nm) RSm (μm) Embodiment 1 Polysilicone 1.32 3.0 5 40 40 3.22 99 153 ○ ○ Embodiment 2 Polysilicone 1.32 3.0 5 40 30 2.90 103 150 ○ ○ Comparison Example 1 Polysilicone 1.32 3.0 5 10 40 1.20 220 140 ○ × Comparison Example 2 PMMA 1.20 3.0 15 40 40 3.30 1798 109 × ○ Comparison Example 3 Polysilicone 1.32 3.0 3 40 40 3.10 76 94 × ○ PMMA 1.20 3.0 1 Comparison Example 4 Polysilicone 1.32 3.0 3 40 20 1.51 99 150 ○ × PMMA 1.20 3.0 1 Comparison Example 5 Polysilicone 1.32 3.0 3 40 10 0.69 135 158 ○ × PMMA 1.20 3.0 1

In Example 1, in which 5 parts by weight of polysilicon particles are formulated as micron particles and 40 parts by weight of silica particles with a particle size of 40 nm are formulated as nanoparticles, the hard coating layer has high adhesion to the anti-reflection layer and the anti-fouling layer, and has good visibility without halo of reflected light. The same is true for Example 2 in which the formulation amount of nano-silicon 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 formulated as nanoparticles, Sa is small, and the adhesion between the hard coating layer and the anti-reflection layer and the anti-fouling layer is insufficient.

In Comparative Example 4, in which 3 parts by weight of polysilicon particles and 1 part by weight of PMMA particles were mixed as micron particles, and 20 parts by weight of silica particles with a particle size of 40 nm were mixed as nanoparticles, Sa was smaller, 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 smaller than that of Comparative Example 4, and the adhesion was insufficient.

It is believed that in Comparative Example 1, the particle size of the nanoparticles is smaller, and the amount of the nanoparticles in Comparative Examples 4 and 5 is less, so nanoscale concavities and convexities are not fully formed on the surface of the hard coating layer, and the adhesion is poorer than that of Examples 1 and 2.

In Comparative Example 2, in which 15 parts by weight of PMMA particles were prepared as micron particles and 40 parts by weight of silica particles with a particle size of 40 nm were prepared as nanoparticles, the adhesion between the hard coating layer and the anti-reflection layer and the antifouling layer was good, but halo was observed in the reflected light, and the visibility was poor compared with Examples 1 and 2. In Comparative Example 2, since the amount of micron particles was large, the in-plane density of the micron particles in the hard coating layer was high, and the average interval RSm of the concave and convex was small, which was considered to be the main cause of the halo of the reflected light.

Comparative Example 3, in which 3 parts by weight of polysilicone particles and 1 part by weight of PMMA particles are prepared as micron particles, also observed halo under reflected light, similar to Comparative Example 2. Similar to Comparative Example 2, Comparative Example 3 is considered to be mainly caused by the smaller RSm. In Comparative Example 3, the preparation of micron particles is the same as that of 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 easy to exist 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 densely packed, so RSm becomes smaller.

From the comparison between the above-mentioned embodiments and the comparative examples, it can be seen that by coexisting micron particles and nano particles in the hard coating layer, adjusting the type, particle size, and blending amount of the particles, increasing the nm-scale surface unevenness index Sa, and increasing the μm-scale unevenness period index RSm, it is possible to obtain an anti-reflection film with excellent adhesion between the hard coating layer and the anti-reflection layer and the anti-fouling layer, less halo of reflected light, and excellent visibility.

1: Hard coating film 3: Primer layer 5: Anti-reflection layer 7: Anti-fouling layer 10: Transparent film substrate 11: Hard coating layer 51: High refractive index layer 52: Low refractive index layer 53: High refractive index layer 54: Low refractive index layer 101: Anti-reflection film

FIG1 is a cross-sectional view showing an example of a laminated structure of an anti-reflection film. FIG2 is a photograph showing the observation of reflected light of the anti-reflection film of the embodiment and the comparative example.

1: Hard coating film

3: Base coating layer

5: Anti-reflective layer

7: Antifouling layer

10: Transparent film substrate

11: Hard coating

51: High refractive index layer

52: Low refractive index layer

53: High refractive index layer

54: Low refractive index layer

101: Anti-reflective film

Claims (10)

An antireflection film, comprising: a hard coating film having a hard coating layer on one main surface of a transparent film substrate, and an antireflection layer and an antifouling layer sequentially disposed on the hard coating layer, the antireflection layer comprising a laminate of a plurality of thin films having different refractive indices, the hard coating layer comprising a binder resin, micron particles having an average particle size of 1 to 8 μm, and nanoparticles having an average primary particle size of 100 nm or less, the average interval RSm of the concavities and convexities calculated in accordance with JIS B0601 based on the roughness curve of the antifouling layer having a measured length of 12 mm measured by a probe method is 120 μm or more, the three-dimensional surface properties of the antifouling layer in an area of 1 μm×1 μm measured by an atomic force microscope are calculated in accordance with ISO 25178 The calculated arithmetic mean height Sa is above 2.0 nm. As in claim 1, the anti-reflection film, wherein the specific gravity of the above-mentioned micron particles is greater than 1.25. The anti-reflection film of claim 2, wherein the amount of particles having a specific gravity of 1.25 or more is 85 parts by weight or more out of a total of 100 parts by weight of the above-mentioned micron particles. The anti-reflection film of any one of claims 1 to 3, wherein the amount of the micron particles in the hard coating layer is 0.5-12 parts by weight relative to 100 parts by weight of the binder resin. The anti-reflection film of any one of claims 1 to 3, wherein the amount of the nanoparticles in the hard coating layer is 25-120 parts by weight relative to 100 parts by weight of the binder resin. The anti-reflection film of any one of claims 1 to 3, wherein the average primary particle size of the nanoparticles is greater than 15 nm. The antireflection film of any one of claims 1 to 3, wherein the arithmetic average roughness Ra calculated according to JIS B0601 based on the roughness curve of the above-mentioned antifouling layer with a measurement length of 12 mm measured by a probe method is 30~500 nm. The anti-reflection film of any one of claims 1 to 3, wherein the anti-reflection layer is a sputtering film. The antireflection film according to any one of claims 1 to 3, wherein a primer layer comprising an inorganic oxide is provided between the hard coating layer and the antireflection layer. An image display device having an anti-reflection film as claimed in any one of claims 1 to 9 arranged on the viewing side surface of an image display medium.