JP2016133722A - Ant-glare film and image display device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-glare film that suppresses glare of a display and offers good slidability for flicking with fingers.SOLUTION: An anti-glare film comprises an anti-glare layer laminated on a transparent base material film, the anti-glare film containing large-diameter fine particles and small-diameter fine particles having a greater density and a smaller particle diameter than the large-diameter fine particles. The large-diameter fine particles have a particle diameter Pdia in a range of 0.1 μm≤Pdia≤5 μm, and a ratio t/Pdia of a film thickness t of the anti-glare layer to the particle diameter Pdia is in a range of 0.05≤t/Pdia≤1.7. The small-diameter fine particles have a particle diameter Mdia in a range of 0.01 μm≤Mdia≤0.1 μm. A ratio Mden/Pden of a density Mden of the small-diameter fine particles to the density Pden of the large-diameter fine particles is in a range of 6.0≥Mden/Pden≥2.7. The large-diameter fine particles occupy 0.5-40%, inclusive, of a total volume of the anti-glare layer, while the small-diameter fine particles occupy 15-65%, inclusive, of the total volume of the anti-glare layer.SELECTED DRAWING: None

Description

  The present invention relates to an anti-glare film, which is less glaring on a display and has a good finger slipperiness during flicking. The present invention also relates to an image display device using the antiglare film.

  A display such as a car navigation system, a smartphone, or a television is required to reflect less light emitted from an external light source such as a fluorescent lamp or sunlight in order to improve the visibility. This is because when the light is reflected on the surface of the display, an image in front of the light is reflected on the display, making it difficult to see the display image. Therefore, by providing an antiglare film having fine irregularities on the surface, the reflected light is scattered to make the reflection inconspicuous.

  Conventionally, the number of pixels of a normal display is about 100 to 150 per 25.4 mm (= 1 inch) in the vertical and horizontal directions of the screen, and if a conventional anti-glare film is used, it is possible to view images without problems. Become. However, the number of pixels per inch, such as car navigation systems, smartphones, and 8K televisions, is increasing, and the number of displays that display high-definition images is increasing. For example, the number of pixels is about 300 per 25.4 mm in length and width of the screen. In some cases, a high-definition display more than twice that of a normal display. One of the purposes is to make the image of a display for normal use more precise. However, when a conventional antiglare film is applied to a display in which the number of pixels is doubled as described above, the visibility is remarkably impaired. That is, when a conventional anti-glare film is provided on the surface of the display, a black mask (or a black matrix, for example, a black line portion provided vertically and horizontally) at the boundary of each pixel of the display, and prevention. There is no particular problem at the location where the concave and convex portions of the glare film overlap, but at the location where the black mask and the concave portion of the antiglare film overlap, the image light is scattered, This is because a scintillation phenomenon that glitters and glitters occurs. When a conventional anti-glare film is applied to a display with the number of pixels doubled as described above, scintillation (surface glare) phenomenon becomes prominent, and characters, lines, pictures, photographs, etc., especially characters and lines Visibility is significantly impaired.

  Patent Document 1 discloses an antiglare film for the purpose of reducing scintillation. In this antiglare film, an antiglare layer containing large and small plastic beads having a specific refractive index difference is laminated on the surface of a transparent substrate film. The particle size of the larger beads is larger than the film thickness of the antiglare layer and protrudes 0.1 to 0.3 μm from the surface of the antiglare layer, which is considered to contribute to antiglare properties, mainly antireflection. On the other hand, smaller beads are contained in the entire anti-glare layer and partly protrude from the surface of the anti-glare layer, which is considered to contribute mainly to the prevention of light diffusion and scintillation.

JP 2009-86677 A

  By the way, as car navigation systems and mobile phones equipped with a capacitive touch panel having a multi-touch function have become popular in recent years, the trend of required performance for surface films has changed, and not only anti-reflection function requirements but also finger slipping There is a new need for sex that has never existed before. However, the conventional anti-glare film is specialized in the function of preventing reflection and cannot meet the needs for improving the slipperiness of the finger.

  Accordingly, an object of the present invention is to provide an anti-glare film with less display glare and good slipperiness of a finger during flicking.

  In the antiglare film of the present invention, an antiglare layer is laminated on a transparent substrate film, and the antiglare layer comprises large-sized fine particles, and small-sized fine particles having a specific gravity larger than the large-sized fine particles and a smaller particle diameter. including. The large-sized fine particles have a particle diameter Pdia of 0.1 μm ≦ Pdia ≦ 5 μm, and a ratio t / Pdia between the film thickness t of the antiglare layer and the particle diameter Pdia is 0.05 ≦ t / Pdia ≦ 1. 7. The particle diameter Mdia of the small-sized fine particles is 0.01 μm ≦ Mdia ≦ 0.1 μm. The ratio Mden / Pden of the specific gravity Mden of the small particle and the specific gravity Pden of the large particle is 6.0 ≧ Mden / Pden ≧ 2.7, and the volume ratio of the large particle to the total volume of the antiglare layer Is 0.5% or more and 40% or less, and the volume ratio of the small-diameter fine particles in the total volume of the antiglare layer is 15% or more and 65% or less.

  The ratio t / Pdia between the film thickness t of the antiglare layer and the particle diameter Pdia of the large fine particles is more preferably 0.05 ≦ t / Pdia ≦ 1.3.

  The volume ratio of the small-sized fine particles in the total volume of the antiglare layer is more preferably 15% or more and 55% or less.

  The small-diameter fine particles are preferably at least one selected from the group consisting of zirconium oxide, titanium oxide, zirconia, zinc oxide, zinc antimonate, tin-doped indium oxide, antimony-doped tin oxide, and silica.

  The large-diameter fine particles are preferably acrylic resin, polystyrene, polymethacrylstyrene, cross-linked acrylic-styrene copolymer resin, silica, benzoguanamine formaldehyde condensate, benzoguanamine / melamine / formaldehyde condensate, melamine / formaldehyde condensate, polyethylene resin, It is at least one selected from the group consisting of epoxy resins, silicone resins, polyvinylidene fluoride, and polyfluorinated ethylene resins.

  A hard coat layer may be laminated between the transparent substrate film and the antiglare layer.

  The antiglare film of the present invention is provided on the surface of an image display device.

  ADVANTAGE OF THE INVENTION According to this invention, the glare of a display can be provided and the anti-glare film with the ease of a finger | toe slip at the time of a flick can be provided.

<Anti-glare film>
The antiglare film is based on a transparent substrate film, and an antiglare layer is laminated on at least one surface thereof, and a hard coat layer is appropriately laminated between the transparent substrate film and the antiglare layer. .

≪Transparent substrate film≫
The transparent substrate film is not particularly limited as long as it is colorless and transparent. Examples of the material for forming such a transparent substrate film include polyesters such as triacetyl cellulose and polyethylene terephthalate, cycloolefin polymers, polycarbonate resins, or polymethyl methacrylate resins, polyarylate, and polyether sulfone. Of these, triacetyl cellulose and polyethylene terephthalate are preferable in terms of high versatility. These transparent base films have a refractive index of about 1.47 to 1.70 for light of 589 nm.

  The thickness of the transparent substrate film is preferably about 25 to 400 μm, more preferably about 50 to 200 μm. When the thickness of the transparent substrate film is thinner than 25 μm or thicker than 400 μm, the handleability during production and use of the antiglare film is lowered.

≪Anti-glare layer≫
The antiglare layer has light transmittance. The antiglare layer has fine irregularities on the surface, and the irregularities scatter reflected light to reduce glare and improve finger slipping.

  The antiglare layer includes at least a large particle and a small particle having different particle diameters and specific gravity, and a binder resin. The antiglare layer can be formed by curing a resin composition for an antiglare layer containing large fine particles, small fine particles, a binder resin, and a photopolymerization initiator as appropriate.

<Large diameter fine particles>
Large diameter fine particles are spherical and have a larger particle size and a lower specific gravity than small diameter fine particles. An uneven shape is formed on the surface of the antiglare film by the large-diameter fine particles. The particle diameter Pdia of the large-sized fine particles is 0.1 μm ≦ Pdia ≦ 5 μm. When the particle diameter Pdia is less than 0.1 μm, the surface unevenness (≈Ra) becomes too small, and thus no antiglare property is exhibited. On the other hand, when the particle diameter Pdia exceeds 5 μm, the surface irregularity interval (≈Sm) becomes large, and the glare-suppressing action is reduced. Moreover, since the contact area with a finger becomes large, finger slipperiness also falls. Preferably, 0.5 μm ≦ Pdia ≦ 3 μm. By controlling to 0.5 μm ≦ Pdia ≦ 3 μm, the size of the surface unevenness (≈Ra) and the surface unevenness interval (≈Sm) can be adjusted more appropriately.

  As long as the particle diameter Pdia of the large-diameter fine particles is a method for measuring the average particle diameter of the particles, any measuring method can be applied. Preferably, the particle diameter Pdia is measured with a transmission electron microscope (magnification of 20,000 to 2,000,000 times). Observation is performed to observe 100 particles, and the average value is defined as the (average) particle diameter.

  Within the above range, the particle diameter Pdia of the large-sized fine particles satisfies the ratio t / Pdia with the film thickness t of the antiglare layer satisfies 0.05 ≦ t / Pdia ≦ 1.7. Here, the film thickness t of the anti-glare layer is the thickness of the portion of the anti-glare layer where there is no protrusion (convex) due to particles. As long as the film thickness t of the antiglare layer is a method for measuring the film thickness, any measurement method can be applied, but preferably, the reflection spectrum of the portion without protrusion (convex) due to particles is measured by a spectral film thickness meter. Then, it is calculated from the obtained reflection spectrum by the peak valley method. When t / Pdia> 1.7, the particle size of the large-sized fine particles is small with respect to the film thickness t and the size of the surface irregularities is small, so that the antiglare property is lowered. When 0.05 ≦ t / Pdia ≦ 1.7, the antiglare property and the glare suppressing action are excellent, and the finger slipping property is good. When t / Pdia ≦ 1.3, the glare-suppressing action is further improved. Moreover, the surface hardness of an anti-glare film can be raised as it is t / Pdia <= 1. The film thickness t is preferably 0.1 μm ≦ t ≦ 5 μm. If the thickness is 0.1 μm> t, the strength of the antiglare layer tends to decrease. When t> 5 μm, the gap between the surface irregularities tends to increase, and the glare tends to increase.

  The material of the large-sized fine particles is not particularly limited as long as the ratio of the specific gravity with the small-sized fine particles is within the range described below, but as a guide, a specific gravity having a specific gravity Pden of Pden ≦ 3.0 can be selected. Examples of such a material include resin and silica. Resins include acrylic resin, polystyrene, polymethacrylstyrene, cross-linked acrylic-styrene copolymer resin, benzoguanamine formaldehyde condensate, benzoguanamine / melamine / formaldehyde condensate, melamine / formaldehyde condensate, polyethylene resin, epoxy resin, silicone resin, polyfluoride. And vinylidene chloride and polyfluoroethylene-based resin. Of these, acrylic, polystyrene, and a cross-linked acrylic-styrene copolymer resin are preferable because they have a low specific gravity and easily exhibit antiglare properties. The large-sized fine particles may be used alone or in combination of two or more.

  The ratio of the volume of the large-sized fine particles to the total volume of the antiglare layer is 0.5% or more and 40% or less. If the volume ratio of the large fine particles is less than 0.5%, sufficient antiglare property cannot be obtained. On the other hand, if the volume ratio of the large-sized fine particles exceeds 40%, the surface irregularities become too large, so that the antiglare property becomes too strong and the visibility is lowered.

<Small particle size>
The small-sized fine particles have a smaller particle size and a larger specific gravity than the large-sized fine particles, and segregate the large-sized fine particles to the upper layer portion of the antiglare layer. The small particle is typically spherical. The particle diameter Mdia of the small-sized fine particles is 0.01 μm ≦ Mdia ≦ 0.1 μm. When the particle diameter Mdia is less than 0.01 μm, the particles are likely to aggregate and it may be difficult to achieve uniform antiglare properties. On the other hand, if the particle diameter Mdia exceeds 0.1 μm, visible light is likely to be scattered, and thus haze may increase. When the particle diameter Mdia is controlled to 0.02 μm ≦ Mdia ≦ 0.07 μm, it is preferable because an effect of segregating large-sized fine particles uniformly on the upper layer portion of the antiglare layer is preferable.

  As the particle size of the small-sized fine particles, any measuring method can be applied as long as it is a method for measuring the average particle size of the particles. Preferably, the particles are observed with a transmission electron microscope (magnification of 20,000 to 2,000,000 times). And 100 particles are observed, and the average value is defined as the (average) particle diameter.

  The specific gravity Mden of the small-sized fine particles is such that the ratio Mden / Pden with the specific gravity Pden of the large-sized fine particles is 6.0 ≧ Mden / Pden ≧ 2.7. When Mden / Pden <2.7, it becomes difficult for the large-diameter fine particles to segregate in the upper layer portion of the antiglare layer, so that the antiglare property is hardly exhibited. Mden / Pden> 6.0 is not preferable because the kind of small-diameter fine particles is limited, and the degree of freedom in selecting a material is reduced, for example, expensive particles such as gold fine particles have to be selected.

  The material of the small-diameter fine particles is not particularly limited as long as the ratio of the specific gravity to the large-diameter fine particles falls within the above range, but as a guide, one having a specific gravity Mden of Mden ≧ 2.5 can be selected. Examples of such a material include metal oxide and silica. Examples of the metal oxide include zirconium oxide, titanium oxide, zirconia, zinc oxide, zinc antimonate, tin-doped indium oxide, and antimony-doped tin oxide. Of these, titanium oxide and zirconium oxide are preferable because of their high refractive index and large specific gravity. The small-diameter fine particles may be used alone or in combination of two or more.

  The content of the small-sized fine particles in the anti-glare layer is such that the proportion of the volume of the small-sized fine particles in the total volume of the anti-glare layer is 15% or more and 65% or less. If the volume ratio of the small-diameter fine particles is less than 15%, the surface irregularity interval (≈Sm) becomes large, and the glare-suppressing action decreases. Moreover, since the contact area with a finger becomes large, finger slipperiness also falls. On the other hand, when the volume ratio of the small-diameter fine particles exceeds 65%, the content of the binder resin is relatively decreased, and the surface hardness of the antiglare film tends to be lowered. More preferably, the volume ratio of the small-diameter fine particles is 55% or less. In this case, the surface hardness of the antiglare film can be increased.

<Binder resin>
Binder resins include monomers, oligomers, and prepolymers having radical polymerizable functional groups such as acryloyl group, methacryloyl group, acryloyloxy group, and methacryloyloxy group, and cationic polymerizable functional groups such as epoxy group, vinyl ether group, and oxetane group. Are used alone, or a composition obtained by appropriately mixing them. Examples of monomers include methyl acrylate, methyl methacrylate, methoxy polyethylene methacrylate, cyclohexyl methacrylate, phenoxyethyl methacrylate, ethylene glycol dimethacrylate, dipentaerythritol hexaacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, and the like. it can. As oligomers and prepolymers, polyester acrylate, polyurethane acrylate, polyfunctional urethane acrylate, epoxy acrylate, polyether acrylate, acrylate compounds such as alkit acrylate, melamine acrylate, silicone acrylate, unsaturated polyester, tetramethylene glycol diglycidyl ether, Epoxy compounds such as propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, bisphenol A diglycidyl ether and various alicyclic epoxies, 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3- Examples include oxetane compounds such as ethyl-3-oxetanyl) methoxy] methyl} benzene and di [1-ethyl (3-oxetanyl)] methyl ether. Door can be. These can be used alone or in combination.

  The binder resin content in the antiglare layer is preferably such that the volume ratio of the binder resin in the total volume of the antiglare layer is 83.5% or less. If it exceeds 83.5%, the content of the large-sized fine particles and the small-sized fine particles decreases, so that the surface unevenness becomes small and the antiglare property is hardly exhibited. Further, the volume ratio of the binder resin is preferably 5% or more. If it is less than 5%, voids are generated in the film and the strength is lowered. More preferably, the volume ratio of the binder resin is 30% or more. In this case, the hardness of the antiglare layer can be increased.

<Photopolymerization initiator>
The photopolymerization initiator is used as a polymerization initiator when the antiglare hard coat layer resin composition is cured by active energy rays such as ultraviolet rays (UV) to form a coating film. The photopolymerization initiator is not particularly limited as long as it initiates polymerization upon irradiation with active energy rays, and known compounds can be used. For example, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 -One, acetophenone polymerization initiators such as 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, benzoin, 2,2-dimethoxy 1,2 -Benzoin polymerization initiators such as diphenylethane-1-one, benzophenone, [4- (methylphenylthio) phenyl] phenylmethanone, 4-hydroxybenzophenone, 4-phenylbenzophenone, 3,3 ', 4,4' -Benzophenone polymerization initiators such as tetra (t-butylperoxycarbonyl) benzophenone, 2-chlorothio Sandton, such thioxanthone type polymerization initiators such as 2,4-diethyl thioxanthone, and the like.

  The volume ratio of the photopolymerization initiator in the total volume of the antiglare layer is preferably 1% or more and 25%. When the photopolymerization initiator is less than the above range, the polymerization becomes insufficient and the adhesion cannot be exhibited. On the other hand, when the amount is more than the above range, the cross-linking density of the film is lowered, and thus the strength is weakened.

<Additives>
The resin composition for the antiglare layer may be prepared as required by a surface preparation agent, a fluorine-based antifouling agent, a silicon-based antifouling agent, a leveling agent, an ultraviolet absorber, an ultraviolet stabilizer, an antioxidant, an antistatic agent, You may contain conventionally well-known additives, such as a foaming agent, in the range which does not impair the effect of this invention.

≪Hard coat layer≫
A hard coat layer can be provided between the transparent substrate film and the antiglare layer in order to increase the surface hardness of the antiglare film. The refractive index nh of the hard coat layer is not particularly limited and can be appropriately applied. However, it is preferable that the difference | nb−nh | from the refractive index nb of the transparent base film does not exceed 0.35. If the difference | nb−nh | between the refractive index nb of the transparent substrate film and the refractive index nh of the hard coat layer exceeds 0.35, the reflectance at the transparent substrate film / hard coat layer interface increases. Transmittance decreases. More preferably, the refractive index nh of the hard coat layer is not less than the refractive index nb of the base material and not more than the refractive index na of the antiglare layer. When the refractive index nh of the hard coat layer is lower than the refractive index nb of the transparent substrate film, the reflectance at the hard coat layer / antiglare layer interface increases, and the transmittance decreases. Further, when the refractive index nh of the hard coat layer is higher than the refractive index na of the antiglare layer, the reflectance at the substrate / hard coat layer interface increases, and the transmittance decreases. The refractive index of the hard coat layer is preferably 1.49 to 1.85. When the refractive index exceeds 1.85, interference unevenness may appear due to interference caused by the difference in refractive index between the transparent base film and the hard coat layer.

  The film thickness of the hard coat layer is preferably 1 μm or more. A film thickness of less than 1 μm is not preferable because the surface hardness cannot be increased effectively. Further, the film thickness of the hard coat layer is preferably 3 μm or more. When the thickness exceeds 20 μm, problems such as a decrease in flex resistance occur, which is not preferable.

  The material for the hard coat layer is not particularly limited as long as it is a known material conventionally used for an antireflection film or the like. For example, a reactive silicon compound such as tetraethoxysilane or an active energy ray curable resin can be used, and these may be mixed. And the hard-coat layer can be formed by irradiating and hardening | curing active energy rays, such as an ultraviolet-ray and an electron beam, to the coating liquid for hard-coat layers prepared by adding a photoinitiator to these.

  Examples of the active energy ray-curable resin include monofunctional (meth) acrylate and polyfunctional (meth) acrylate. Specifically as monofunctional (meth) acrylate, (meth) acrylic acid alkyl ester, (meth) acrylic acid (poly) ethylene glycol group-containing (meth) acrylic acid ester and the like are preferable. Examples of the polyfunctional (meth) acrylate include ester compounds of polyhydric alcohol and (meth) acrylic acid, polyfunctional polymerizable compounds containing two or more (meth) acryloyl groups such as urethane-modified acrylate, and the like.

  Among these, from the viewpoint of achieving both productivity and hardness, a cured product of a composition containing an active energy ray-curable resin having a pencil hardness (evaluation method: JIS-K5600-5-4) of H or higher is preferable. . The composition containing such an active energy ray curable resin is not particularly limited. For example, a known active energy ray curable resin or a mixture of two or more known active energy ray curable resins may be mixed. And those commercially available as ultraviolet curable hard coat materials.

  The photopolymerization initiator is used as a polymerization initiator when a coating film is formed by curing the hard coat layer coating liquid with an active energy ray such as ultraviolet (UV). The photopolymerization initiator is not particularly limited as long as it initiates polymerization upon irradiation with active energy rays, and known compounds can be used. For example, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 -One, acetophenone polymerization initiators such as 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, benzoin, 2,2-dimethoxy 1,2 -Benzoin polymerization initiators such as diphenylethane-1-one, benzophenone, [4- (methylphenylthio) phenyl] phenylmethanone, 4-hydroxybenzophenone, 4-phenylbenzophenone, 3,3 ', 4,4' -Benzophenone polymerization initiators such as tetra (t-butylperoxycarbonyl) benzophenone, 2-chlorothio Xanthone, such thioxanthone type polymerization initiators such as 2,4-diethyl thioxanthone, and the like.

  The solvent of the coating solution is not particularly limited as long as it is a known one that has been conventionally used for the coating solution for forming each layer in this type of antireflection film, and examples thereof include alcohol-based, ketone-based, and ester-based solvents. Can be selected in a timely manner.

  Furthermore, the hard coat layer may contain other additives. Other additives include inorganic particles for adjusting the refractive index, antistatic agents, surface adjusting agents, and the like. As the antistatic agent, conductive metal oxide fine particles such as ATO fine particles and ITO fine particles, conductive polymers such as PEDOT, and surfactants such as quaternary ammonium salts can be used. As the surface conditioner, a silicon leveling agent such as polydimethylsiloxane or an acrylic leveling agent can be used.

≪Formation of each layer≫
The method for forming the antiglare layer and the hard coat layer is not particularly limited.For example, by applying the wet coating method, each coating liquid prepared by appropriately diluting the resin composition for each layer with a solvent is applied to the transparent base film. The method of apply | coating and hardening can be employ | adopted. As the coating method, the wet coating method is particularly preferable in terms of productivity and production cost. The wet coating method may be a known method, and typical examples include a roll coating method, a die coating method, a spin coating method, and a dip coating method. In these, the method which can form a coating film continuously, such as a roll coat method, is preferable from the point of productivity. The formed coating film can form a cured film by performing a curing reaction by heating, irradiation with active energy rays such as ultraviolet rays and electron beams.

<Image display device with antiglare film on its surface>
An image display device including the antiglare film on the surface of the screen can suppress reflection of light on the screen, suppress glare, and can easily slide a finger during flicking. Examples of the image display device include a car navigation system, a smartphone, a mobile PC, and an electronic blackboard display. The antiglare film is attached to the observation side surface of the image display device via an OCA (optical clear adhesive) or attached to the observation side surface as a polarizing film. In the case of using an antiglare film as a polarizing film, the polarizing film generally has a protective film on at least one surface of a polarizer composed of a polyvinyl alcohol-based resin film adsorbed and oriented with iodine or a dichroic dye. Although there are many laminated | stacked forms, if the said anti-glare film is bonded to one side of such a polarizing film, it will become a polarizing film with an anti-glare antireflection effect. Further, the antiglare film has an antiglare antireflection effect by using the antiglare film also as a protective film and pasting the antiglare film on one surface of the polarizer so that one surface on which the antiglare layer is laminated becomes the outside. It can be set as a polarizing film.

  Hereinafter, the embodiment will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the scope of these examples.

[Transparent substrate film]
In each Example and Comparative Example, the following were used as the transparent substrate film.
Triacetyl cellulose (TAC)
“TD80UL” manufactured by FUJIFILM Corporation 80 μm, refractive index 1.48
Polyethylene terephthalate (PET)
“U403” 100 μm manufactured by Toray Industries, Inc., refractive index 1.65
Cycloolefin polymer (COP)
“ZEONOR FILM” manufactured by Nippon Zeon Co., Ltd. 80 μm, refractive index 1.53

[Resin composition for anti-glare layer]
As the resin composition for the antiglare layer, the following raw materials were used, and the respective raw materials were mixed in the compositions described in Tables 1 to 6 below to prepare resin compositions AG-1 to AG-39 for the antiglare layer. . In addition, the volume ratio of each raw material shows the ratio of the volume of the said raw material in the resin composition whole volume for glare-proof layers.

<Small particle size>
Titanium oxide fine particles (dispersion)
“RTTMEK25WT% -F02” manufactured by CIK Nanotech Co., Ltd., particle size 0.015 μm
Zirconia (dispersion)
"ZRMEK25% -F47" manufactured by CII Kasei Co., Ltd., particle size 0.015 µm
Zinc antimonate fine particles (AZO) (dispersion)
“CELNAX CX-603M-F2” manufactured by Nissan Chemical Industries, Ltd., particle size 0.05 μm
ITO fine particles (dispersion)
“Conductive EI-3NMHR3, 35%” manufactured by Dainippon Paint Co., Ltd., particle size 0.05 μm
Silica ultrafine particles (dispersion)
“IPA-ST, 30%” manufactured by Nissan Chemical Co., Ltd., particle size 0.03 μm
Silica ultrafine particle “SIMIBK15WT% -H58” manufactured by CIK Nanotech Co., Ltd., particle size 0.1 μm
Antimony-tin oxide fine particles (ATO)
Product name: ATO, particle size 0.05 μm, manufactured by Nissan Chemical Industries
Zinc oxide Air Brown Co., Ltd. “TECNAPOW-ZNO”, particle size 0.02μm

<Large diameter fine particles>
Acrylic (PMMA), particle size 0.8μm “MX-80H3wT” by Soken Chemical Co., Ltd.
Acrylic (PMMA), particle size 3μm “MX-300” manufactured by Soken Chemical Co., Ltd.
Acrylic (PMMA), particle size 5μm “MX-500” manufactured by Soken Chemical Co., Ltd.
Acrylic (PMMA), particle size 8μm “SSX-108” manufactured by Sekisui Plastics Co., Ltd.
Polystyrene (PS), particle size 3.5 μm “Made by Soken Chemical Co., Ltd., SX-350H”
Cross-linked acrylic-styrene copolymer resin (MS), particle size 0.8μm
"SSX1008QXE" manufactured by Sekisui Plastics Co., Ltd.
Cross-linked acrylic-styrene copolymer resin (MS), particle size 5 μm
"SSX1055QXE" manufactured by Sekisui Plastics Co., Ltd. Monodispersed fine particle silica with uniform particle size, particle size 0.8μm "Sicastar 43-00-802" manufactured by Corefront Co., Ltd.

<Binder resin>
Dipentaerythritol hexaacrylate, “KAYARAD DPHA” manufactured by Nippon Kayaku Co., Ltd.
Urethane acrylate “Shikou UV7600B” manufactured by Nippon Synthetic Chemical Industry Co., Ltd., molecular weight 1400, viscosity at 60 ° C. is 2500-4500 Pa · s
Pentaerythritol triacrylate (PE3A)
“PET30” manufactured by Nippon Kayaku Co., Ltd.

<Photopolymerization initiator>
“IRGACURE 184 (I-184)” manufactured by Ciba Specialty Chemicals Co., Ltd.

[Resin composition for hard coat layer]
The following commercially available products were used as the resin composition for the hard coat layer.
Hard coat "Rioduras LAS1303NL" manufactured by Toyo Ink Co., Ltd.

(Example 1-1)
On one side of FUJIFILM TAC film “TD80UL, 80 μm”, the film thickness after curing the resin composition for anti-glare (AG-1) with a bar coater (the film thickness of the part where particles are not present) is 0.2 μm. The antiglare film was prepared by forming the antiglare layer by applying 400 mJ of ultraviolet light with a 120 W high pressure mercury lamp and curing it.

(Examples 1-2 to 1-19, 1-21 to 30, Comparative Examples 1-1 to 1-13)
Using the materials shown in Tables 7 to 11, antiglare films were prepared in the same manner as in Example 1-1.

(Example 1-20)
A hard coat resin composition was applied to one surface of a TAC film “TD80UL, 80 μm” made by Fuji Film so that the film thickness after curing was 4 μm with a bar coater, and irradiated with 400 mJ ultraviolet rays with a 120 W high pressure mercury lamp. A clear hard coat layer was formed by curing. Next, an antiglare layer was provided on the clear hard coat layer by the same method as in Example 1-1 to produce an antiglare film.

  About the obtained anti-glare film of each Example and a comparative example, various characteristics were measured and evaluated by the following method. The results are also shown in Tables 7-11.

<Refractive index of transparent substrate film>
It measured by the method of JISK7142-2014.

<The refractive index of each layer composition after curing>
(1) On the TAC film [trade name “TD80UL”, manufactured by FUJIFILM Corporation], the thickness of each layer is such that the coating liquid for each layer is 100 to 1000 nm in thickness after drying and curing by a bar coater. Was adjusted and applied. After drying, the film was cured by irradiating with 400 mJ of ultraviolet light using a 120 W high-pressure mercury lamp in a nitrogen atmosphere with an ultraviolet irradiation device (manufactured by Iwasaki Electric Co., Ltd.) to prepare a film for refractive index measurement.
(2) The reflection spectrum was measured with a reflection spectral film thickness meter [“FE-3000”, manufactured by Otsuka Electronics Co., Ltd.] after roughening the back surface of the produced film with sandpaper and painting with black paint.
(3) From the reflectance read from the reflection spectrum, the constant of the wavelength dispersion formula (Formula 1) of n-Cauchy shown below was obtained, and the refractive index at the wavelength of 589 nm was obtained.
N (λ) = a / λ ⁴ + b / λ ² + c (Formula 1)
The refractive index of the antiglare layer is calculated by curing a composition excluding the large particles among the compositions constituting the antiglare layer to form a cured film, and measuring the reflection spectrum of the cured film. did.

<Film thickness of antiglare layer>
The reflection spectrum of a portion without protrusion (convex) due to particles was measured with a spectral film thickness meter (FE3000, manufactured by Otsuka Electronics Co., Ltd.), and the peak reflection method was calculated from the obtained reflection spectrum.

<Surface roughness>
Arithmetic average roughness in accordance with the provisions of JIS B 0601-1994, using a surface roughness measuring machine manufactured by Kosaka Laboratory Co., Ltd., Surfcorder SE500, under conditions of a scanning range of 4 mm and a scanning speed of 0.2 mm / s. Ra (μm) and the average interval Sm (mm) of the irregularities were measured.

<Visibility reflectance>
In order to remove the back surface reflection of the measurement surface, the back surface was roughened with sandpaper and painted with a black paint, and a light wavelength of 380 nm to 780 nm was measured with a spectrophotometer [trade name: U-best 560 manufactured by JASCO Corporation]. The 5 ° and −5 ° specular reflection spectra were measured. Viewing the tristimulus value Y of the object color due to reflection in the XYZ color system assumed in JIS Z8701, using the spectral reflectance of the obtained light with a wavelength of 380 nm to 780 nm and the relative spectral distribution of the CIE standard illuminant D65. Sensitivity reflectance (%) was used.

<All haze>
A haze meter (Nippon Denshoku Industries Co., Ltd., NDH2000) was used, and the haze value (%) as an optical characteristic was measured.

<Internal haze>
The internal haze value is a haze value measured by dropping water droplets on the surface of the antiglare hard coat layer and pressing glass there.

<External haze>
External haze = total haze-calculated by internal haze.

<Anti-Glare: Reflected image is unclear>
When the fluorescent lamp light is reflected so that the fluorescent lamp distance is 3 m and the incident angle is 10 ° on the surface on which the antiglare hard coat layer is laminated, how much the outline of the fluorescent lamp reflected regularly at 10 ° is blurred. Was evaluated according to the following evaluation criteria. As the fluorescent lamp, FHF32EXNH manufactured by Panasonic Corporation was used.
○: Blurred so that the outline cannot be confirmed.
X: The outline is not blurred or blurred so that the outline cannot be confirmed, but the visibility of the image is poor.

<Glitter>
An anti-glare film was placed on the outermost surface on the image display side of a high-definition liquid crystal touch panel as a high-definition liquid crystal display, and the glare was measured visually and evaluated in the following three stages.
A: No glare, B: Slight glare, but not worrisome, X: Glitter as worrisome.

<Finger slipperiness>
The coefficient of dynamic friction with respect to an artificial skin model of urethane elastomer material (trade name: Bio Skin Plate Plate #BS Color 1, manufactured by Beaulux Co., Ltd.) was measured by a measurement method based on JIS K 7125-1999. The coefficient of friction evaluated by this evaluation method correlates with the slipperiness when flicking with a human finger. The smaller the coefficient of friction, the easier the finger slides, and the higher the coefficient of friction, the less sensitive the finger is. It was evaluated. In addition, when the friction coefficient is such that the friction coefficient ≦ 0.5, 90% or more of the evaluators (N = 30) determined that the finger is easy to slip when flicking.

<Surface hardness>
The load was set to 750 g and evaluated according to JIS K 5600.

  From the results of the examples, the particle diameter Pdia of the large-sized fine particles contained in the antiglare layer is 0.1 μm ≦ Pdia ≦ 5 μm, and the ratio t / Pdia of the film thickness t of the antiglare layer and the particle diameter Pdia is 0. 0.05 ≦ t / Pdia ≦ 1.7, the particle diameter Mdia of the small particle is 0.01 μm ≦ Mdia ≦ 0.1 μm, and the ratio Mden / Pden of the specific gravity Mden of the small particle and the specific gravity Pden of the large particle is 6.0 ≧ Mden / Pden ≧ 2.7, and the volume ratio of the large diameter fine particles occupying the total volume of the antiglare layer is 0.5% to 40%, and the small diameter fine particles occupying the total volume of the antiglare layer When the volume ratio is 15% or more and 65% or less, moderate unevenness is formed on the anti-glare film, the anti-glare property is excellent, the glare is small, and the ease of finger sliding during flicking is good.

  On the other hand, in Comparative Examples 1-1, 1-4, 1-12, and 1-13, the volume ratio of the small-diameter fine particles in the total volume of the antiglare layer is small, and the antiglare property is inferior. In Comparative Example 1-2, the volume ratio of the large-sized fine particles in the total volume of the antiglare layer is small, and the antiglare property is inferior. In Comparative Example 1-3, the volume ratio of the large-sized fine particles occupying the entire volume of the antiglare layer is large, and since appropriate unevenness is not formed, the antiglare property is inferior and the haze is large. In Comparative Example 1-5, since the particle diameter of the large-sized fine particles is small with respect to the film thickness, moderate unevenness is not formed and the antiglare property is inferior. In Comparative Examples 1-6 to 1-10, since the specific gravity difference between the large-sized fine particles and the small-sized fine particles is small, the antiglare property is inferior and the glare is large. Moreover, finger slipperiness is also inferior. In Comparative Example 1-11, the particle diameter of the large-sized fine particles is large and the glare is large.

Claims (7)

An antiglare layer is laminated on the transparent substrate film,
The antiglare layer includes large-sized fine particles, and small-sized fine particles having a specific gravity larger than the large-sized fine particles and a small particle size,
The large-sized fine particles have a particle diameter Pdia of 0.1 μm ≦ Pdia ≦ 5 μm, and a ratio t / Pdia between the film thickness t of the antiglare layer and the particle diameter Pdia is 0.05 ≦ t / Pdia ≦ 1. 7 and the particle diameter Mdia of the small particle is 0.01 μm ≦ Mdia ≦ 0.1 μm,
The ratio Mden / Pden of the specific gravity Mden of the small particle and the specific gravity Pden of the large particle is 6.0 ≧ Mden / Pden ≧ 2.7,
The volume ratio of the large-sized fine particles in the total volume of the anti-glare layer is 0.5% or more and 40% or less, and the volume ratio of the small-sized particles in the total volume of the anti-glare layer is 15% or more and 65% or less. An anti-glare film.   2. The antiglare film according to claim 1, wherein a ratio t / Pdia of a film thickness t of the antiglare layer and a particle diameter Pdia of the large fine particles satisfies 0.05 ≦ t / Pdia ≦ 1.3.   The antiglare film according to claim 1 or 2, wherein a volume ratio of the small-diameter fine particles occupying the entire volume of the antiglare layer is 15% or more and 55% or less.   The small-sized fine particles are at least one selected from the group consisting of zirconium oxide, titanium oxide, zirconia, zinc oxide, zinc antimonate, tin-doped indium oxide, antimony-doped tin oxide, and silica. The anti-glare film as described in any one of Claims.   The large-sized fine particles are acrylic resin, polystyrene, polymethacrylstyrene, cross-linked acrylic-styrene copolymer resin, silica, benzoguanamine formaldehyde condensate, benzoguanamine / melamine / formaldehyde condensate, melamine / formaldehyde condensate, polyethylene resin, epoxy resin, The antiglare film according to any one of claims 1 to 4, wherein the antiglare film is at least one selected from the group consisting of a silicone resin, polyvinylidene fluoride, and a polyvinyl fluoride resin.   The antiglare film according to any one of claims 1 to 5, wherein a hard coat layer is laminated between the transparent substrate film and the antiglare layer.   An image display device comprising the antiglare film according to any one of claims 1 to 6 on a surface thereof.