Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B3/00—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
  • B32B3/26—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer
  • B32B3/30—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer characterised by a layer formed with recesses or projections, e.g. hollows, grooves, protuberances, ribs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
  • B32B7/02—Physical, chemical or physicochemical properties
  • B32B7/023—Optical properties
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
  • G02B1/11—Anti-reflection coatings
  • G02B1/111—Anti-reflection coatings using layers comprising organic materials
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
  • G02B1/18—Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/02—Diffusing elements; Afocal elements
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
  • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements

Definitions

• the present invention relates to an optical laminate and an image display device using the same.
• Anti-glare (AG) film is an anti-glare layer made of a resin layer containing a filler laminated onto a transparent substrate, and prevents external light from being reflected by diffusing reflected light with the unevenness of the anti-glare layer's surface.
• Anti-glare low-reflection (AGLR) films are also known, which have a low refractive index layer (low-reflection (LR) layer) laminated onto the anti-glare layer of an AG film, and further suppress reflected light by using optical interference.
• AG films and AGLR films (hereinafter collectively referred to as "anti-glare films”) are used in a variety of displays.
• Patent No. 7192777 International Publication No. 2019/026471
• Anti-glare films for anti-reflective touch panel displays are required to have anti-glare optical properties as well as good wipeability of fingerprints that adhere to the film during operation. To achieve this, it is common to add anti-stain ingredients such as fluorine compounds or silicone compounds to the outermost layer, but there is a limit to how much improvement can be made to the ease of wiping off fingerprints simply by adding these anti-stain ingredients.
• the present invention aims to provide an optical laminate that has excellent glare resistance and fingerprint wipeability, and an image display device using the same.
• An optical laminate having an uneven shape on an outermost surface the optical laminate being characterized by satisfying the following conditions (1) and (2): 800 ⁇ A ⁇ 5,500 (1) 0 ⁇ B ⁇ 100 (2)
• three-dimensional data of the unevenness height obtained by measuring the unevenness shape using an optical interference method or a contact method is converted into first image data having the unevenness height as a pixel value
• the first image data is converted into a second image by fast Fourier transform
• the spatial frequency f of the X coordinate of the power spectrum of an image passing through the origin and within a range of ⁇ 20 pixels on the positive X axis of the second image is calculated:
• B The average value of the power spectrum intensity in the range of 200 cycle/mm ⁇ f ⁇ 250 cycle/mm.
• the present invention provides an optical laminate with excellent glare resistance and fingerprint wipeability, and an image display device using the same.
• FIG. 1 is a cross-sectional view that illustrates an example of an optical laminate according to an embodiment.
• FIG. 2 is a cross-sectional view that illustrates another example of the optical laminate according to the embodiment.
• FIG. 3 is a diagram showing a method for evaluating antiglare properties.
• FIG. 4 is a diagram showing an example of evaluation of antiglare properties.
• FIG. 1 is a cross-sectional view showing a schematic example of an optical laminate according to an embodiment.
• the optical laminate 11 comprises a transparent substrate 2 and an antiglare layer (first functional layer) 3 laminated on one side of the transparent substrate 2.
• the optical laminate 11 is an optical film (also called an "AG film”) that scatters incident light using the fine unevenness of the surface of the antiglare layer 3 to suppress reflections of external light.
• the transparent substrate 2 is a film that serves as the base of the optical laminate 11, and is made of a material that has excellent transparency to visible light.
• Materials that can be used to form the transparent substrate 2 include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyacrylates such as polymethyl methacrylate, polyamides such as nylon 6 and nylon 66, polyimides, polyarylates, polycarbonates, triacetyl cellulose, polyacrylates, polyvinyl alcohol, polyvinyl chloride, cycloolefin copolymers, norbornene-containing resins, polyethersulfone, and polysulfone, as well as transparent resins and inorganic glass.
• the thickness of the transparent substrate 2 There are no particular limitations on the thickness of the transparent substrate 2, but it is preferable that it be 10 to 200 ⁇ m.
• the surface of the transparent substrate 2 may be subjected to a surface modification treatment in order to improve adhesion with other layers to be laminated.
• surface modification treatments include alkali treatment, corona treatment, plasma treatment, sputtering treatment, application of a surfactant or a silane coupling agent, and Si vapor deposition.
• the anti-glare layer 3 is a functional layer that forms the fine uneven shape on the outermost surface of the optical laminate 11.
• the anti-glare layer 3 is formed by applying a coating liquid containing an active energy ray-curable compound and organic and/or inorganic fine particles (filler) to the transparent substrate 2 and curing the coating.
• a monofunctional, difunctional, trifunctional or higher functional (meth)acrylate monomer can be used as the active energy ray curable compound.
• (meth)acrylate is a general term for both acrylate and methacrylate
• (meth)acryloyl is a general term for both acryloyl and methacryloyl.
• Examples of monofunctional (meth)acrylate compounds include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, glycidyl (meth)acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isobornyl (meth)acrylate, and isodecyl (meth)acrylate.
• bifunctional (meth)acrylates include di(meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, ethoxylated hexanediol di(meth)acrylate, propoxylated hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and hydroxypivalic acid neopentyl
• trifunctional or higher (meth)acrylates examples include trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, and other trifunctional (meth)acrylate compounds such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tri(meth)acrylate.
• Examples of such compounds include trifunctional or higher polyfunctional (meth)acrylate compounds such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ditrimethylolpropane hexa(meth)acrylate, as well as polyfunctional (meth)acrylate compounds in which a portion of these (meth)acrylates is substituted with an alkyl group or ⁇ -caprolactone.
• polyfunctional (meth)acrylate compounds such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipenta
• urethane (meth)acrylates can also be used as polyfunctional monomers.
• examples of urethane (meth)acrylates include those obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and then reacting the resulting product with a (meth)acrylate monomer having a hydroxyl group.
• urethane (meth)acrylates examples include pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate toluene diisocyanate urethane prepolymer, pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate isophorone diisocyanate urethane prepolymer, etc.
• the above-mentioned polyfunctional monomers may be used alone or in combination of two or more.
• the above-mentioned polyfunctional monomers may be monomers in the coating liquid or may be partially polymerized oligomers.
• the organic fine particles are a material that mainly forms minute irregularities on the surface of the anti-glare layer 3, imparting the function of diffusing external light.
• resin particles made of a light-transmitting resin material such as acrylic resin, polystyrene resin, styrene-(meth)acrylic acid ester copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride, or polyethylene fluoride resin can be used.
• a light-transmitting resin material such as acrylic resin, polystyrene resin, styrene-(meth)acrylic acid ester copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride, or polyethylene fluoride resin
• two or more types of resin particles with different materials may be mixed and used.
• the average particle size of the organic fine particles is preferably 0.5 to 10 ⁇ m.
• the inorganic fine particles added to the composition for forming the antiglare layer are preferably nanoparticles with an average particle size of 10 to 200 nm.
• the inorganic fine particles are a material for adjusting the sedimentation and aggregation of the organic fine particles in the anti-glare layer 3.
• examples of the inorganic fine particles that can be used include silica fine particles, metal oxide fine particles, and various mineral fine particles.
• examples of the silica fine particles that can be used include colloidal silica and silica fine particles surface-modified with reactive functional groups such as (meth)acryloyl groups.
• Examples of the metal oxide fine particles that can be used include alumina, zinc oxide, tin oxide, antimony oxide, indium oxide, titania, and zirconia.
• Examples of the mineral fine particles that can be used include mica, synthetic mica, vermiculite, montmorillonite, iron montmorillonite, bentonite, beidellite, saponite, hectorite, stevensite, nontronite, magadiite, ilealite, kanemite, layered titanic acid, smectite, and synthetic smectite.
• the mineral fine particles may be either natural or synthetic (including substituted or derivative), or a mixture of both may be used.
• layered organic clay is more preferred.
• Layered organic clay refers to a swelling clay having an organic onium ion introduced between the layers.
• the organic onium ion is not limited as long as it can be organized by utilizing the cation exchange property of the swelling clay.
• the above-mentioned synthetic smectite can be preferably used.
• Synthetic smectite has the function of increasing the viscosity of the composition for forming the antiglare layer, suppressing the settling of the resin particles and inorganic fine particles, and adjusting the uneven shape of the surface of the optical functional layer.
• a polymerization initiator may be added to cure the antiglare layer-forming composition by ultraviolet irradiation.
• the polymerization initiator may be a polymerization initiator that generates radicals by ultraviolet irradiation.
• the polymerization initiator may be a radical polymerization initiator such as acetophenone, benzophenone, thioxanthone, benzoin, benzoin methyl ether, or acylphosphine oxide.
• the polymerization initiator may be, for example, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-phenylacetophenone, dibenzoyl, benzoin, benzoin methyl ether, benzoin ethyl ether, p-chlorobenzophenone, p-methoxybenzophenone, Michler's ketone, acetophenone, or 2-chlorothioxanthone.
• One of these may be used alone, or two or more may be used in combination.
• an antifouling agent a leveling agent, an oil repellent, a water repellent, and an agent for preventing fingerprint adhesion to the composition for forming the antiglare layer as components for improving the antifouling properties.
• Fluorine-containing compounds and silicone compounds can be preferably used as these additives.
• an antifouling compound By adding an antifouling compound to the antiglare layer 3, which is the outermost layer, the ease of wiping off fingerprints can be further improved.
• various additives such as antistatic agents, defoamers, antioxidants, ultraviolet absorbers, infrared absorbers, colorants, light stabilizers, polymerization inhibitors, and photosensitizers may be added as necessary.
• a solvent may be added to the composition for forming the antiglare layer, if necessary.
• the solvent one or more of the following may be used in combination: alcohols such as methanol, ethanol, 1-propanol, 2-propanol, butanol, isopropyl alcohol, isobutanol, etc.; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, etc.; ketone alcohols such as diacetone alcohol, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, etc.; glycols such as ethylene glycol, propylene glycol, hexylene glycol, etc.; glycol ethers such as ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, diethyl cellosolve, diethyl carbitol, prop
• FIG. 2 is a cross-sectional view showing a schematic diagram of another example of an optical film according to an embodiment.
• the optical laminate 12 comprises a transparent substrate 2, an anti-glare layer (first functional layer) 3 laminated on one side of the transparent substrate 2, and a low refractive index (second functional layer) layer 4 laminated on the surface of the anti-glare layer 3 and having a lower refractive index than the anti-glare layer 3.
• the optical laminate 12 is an optical film (also called an "AGLR film") that suppresses glare and reflection of external light by utilizing scattering of incident light and optical interference due to fine irregularities on the outermost surface.
• the low refractive index layer 4 has a refractive index lower than that of the underlying anti-glare layer 3, and is a functional layer that suppresses reflection through optical interference.
• the low refractive index layer 4 can be formed by applying a composition containing an active energy ray-curable compound to the surface of the antiglare layer 3 and curing the coating.
• the low refractive index layer 4 may contain low refractive index fine particles to adjust the refractive index.
• the low refractive index fine particles for example, LiF, MgF, 3NaF.AlF or AlF (each has a refractive index of 1.4), or Na 3 AlF 6 (cryolite, a refractive index of 1.33), or silica fine particles having voids inside can be suitably used.
• Silica fine particles having voids inside can make the refractive index of the voids (about 1) of air, so they are useful for lowering the refractive index of the low refractive index layer 4.
• porous silica particles and silica particles having a shell structure can be used.
• the low refractive index fine particles are not necessarily required, and when the refractive index of the active energy ray curable compound after curing is lower than the refractive index of the antiglare layer 3, the low refractive index fine particles may be omitted.
• the active energy ray-curable compound the polymerizable compound described in the antiglare layer can be used.
• the above-mentioned polymerization initiator and solvent may be appropriately added to the composition for forming the low refractive index layer.
• the low refractive index layer 4 is a functional layer that is the outermost layer, it is preferable to add an antifouling agent, a leveling agent, an oil repellent, a water repellent, or an anti-fingerprint agent to the composition for forming the low refractive index layer as a component that improves the antifouling properties.
• an antifouling agent a leveling agent, an oil repellent, a water repellent, or an anti-fingerprint agent
• Fluorine-containing compounds and silicone compounds can be preferably used as these additives.
• various additives such as antistatic agents, defoamers, antioxidants, ultraviolet absorbers, infrared absorbers, colorants, light stabilizers, polymerization inhibitors, and photosensitizers may be added as necessary.
• one or more other functional layers such as a hard coat layer, a high refractive index layer, a medium refractive index layer, an antistatic layer, an electromagnetic wave blocking layer, an infrared absorbing layer, an ultraviolet absorbing layer, a color correction layer, etc. may be laminated.
• the method of applying the antiglare layer-forming composition and the low refractive index layer-forming composition is not particularly limited, and for example, they can be applied using a spin coater, roll coater, reverse roll coater, gravure coater, microgravure coater, knife coater, bar coater, wire bar coater, die coater, dip coater, spray coater, applicator, etc.
• the uneven shape of the outermost surface of the optical function laminate according to this embodiment satisfies the following conditions (1) and (2). 800 ⁇ A ⁇ 5,500 (1) 0 ⁇ B ⁇ 100 (2)
• a and B are values derived from the spatial frequency f calculated from a predetermined range of the image (power spectrum image) after fast Fourier transform (hereinafter referred to as "FFT") of image data generated from the measurement data of the unevenness height of the optical laminate surface.
• A is the average value of the power spectrum intensity in the range of 50 cycle/mm ⁇ f ⁇ 100 cycle/mm
• B is the average value of the power spectrum intensity in the range of 200 cycle/mm ⁇ f ⁇ 250 cycle/mm.
• three-dimensional data of the unevenness height of the outermost surface of the optical laminate is obtained by measurement.
• the three-dimensional data of the unevenness height includes the position in the measurement surface and the unevenness height.
• the three-dimensional data of the unevenness height of the outermost surface can be measured by an optical interference method or a contact method.
• the obtained three-dimensional data is converted into an image (first image) in which the unevenness height is the pixel value.
• FFT is performed on the first image to obtain an image after FFT processing (second image).
• the X coordinate of the power spectrum in a predetermined range in the second image after FFT processing is converted into a spatial frequency f. From the obtained spatial frequency, the average value of the real number of the power spectrum intensity in the range of 50 cycle/mm ⁇ f ⁇ 100 cycle/mm and the range of 200 cycle/mm ⁇ f ⁇ 250 cycle/mm is calculated, and is set as the above values A and B.
• the inventors of the present application have studied irregularity shapes that can improve fingerprint wiping properties, they have found that the power spectrum intensity around a spatial frequency of 50 cycle/mm is closely related to fingerprint wiping properties, and that the higher the power spectrum intensity around a spatial frequency of 50 cycle/mm (i.e., the higher the irregularity height), the better the fingerprint wiping properties.
• the optical laminates 11 and 12 according to this embodiment have excellent fingerprint wiping properties because the uneven shape of the outermost surface satisfies the above conditions (1) and (2). If either the value of A or B is outside the range of conditions (1) and (2), the fingerprint wiping properties will deteriorate, or the optical properties will deteriorate, such as increased haze or a whitish appearance due to increased surface scattering.
• the values of A and B can be controlled by adjusting the particle size and amount of the filler added to the anti-glare layer 3, the amount of the additive, the film thickness of the anti-glare layer 3, and the aggregation state of the filler in the film formation process.
• the ease of wiping off fingerprints can be further improved by adding anti-fouling agents or other anti-fouling ingredients to the functional layer, which is the outermost layer.
• Glare resistance can be evaluated based on the "glare contrast" value defined in JIS C1006:2019. If the glare contrast is 3% or less, the glare is not visible and the glare resistance can be evaluated as good. If the glare contrast is 3% or less, the glare is not visible and the glare resistance is good.
• Glitter contrast can be calculated as follows. First, the display screen of the image display device lit in a single color (e.g., green) is photographed using an imaging element. Next, the pixel pattern is removed from the photographed image using image processing to obtain two-dimensional gradation data (glare pattern). Next, the standard deviation (glare value) of all the illuminance distribution data that constitutes the obtained glitter pattern is calculated. The percentage of the glitter value relative to the average value of all the illuminance distribution data that constitutes the glitter pattern is then calculated as the glitter contrast.
• a single color e.g., green
• Glitter contrast increases as the resolution (ppi) of the image display device increases.
• the value of the resolution x used in the measurement includes at least values selected from the ranges of 250 to 270 ppi and 500 to 520 ppi. If the coefficient a of the linear approximation equation is less than 0.015, the optical laminate has suppressed glitter contrast even when used in an image display device with high resolution.
• the glare contrast y value measured at one or more resolutions x selected from the ranges of, for example, 80 to 99 ppi, 100 to 119 ppi, 120 to 140 ppi, and 160 to 180 ppi for the approximation.
• the haze value (total haze) of the optical laminate according to the present invention is preferably 1.5 to 35%.
• the haze value is a value measured in accordance with JIS K7136. If the haze value is less than 1.5%, antiglare properties cannot be obtained, which is not preferable. Also, if the haze value exceeds 35%, the appearance becomes white, which is not preferable.
• the optical laminates 11 and 12 according to this embodiment can be used to form an image display device by being attached to the outermost surface of an image display panel such as a liquid crystal panel or an organic EL panel.
• a touch panel may be provided between the optical laminates 11 and 12 and the image display panel.
• the optical laminates 11 and 12 according to this embodiment have excellent fingerprint wiping properties, and are therefore suitable as optical films to be provided on the outermost surface of an image display device equipped with a touch panel.
• Example 1 Composition for forming anti-glare layer
• Organic fine particles having an average particle size of 3 ⁇ m (MX-300, refractive index 1.49, manufactured by Soken Chemical Industries, Ltd.) and organoclay (Sumecton SAN, manufactured by Kunimine Kogyo Co., Ltd.) were dispersed by stirring for 40 minutes in toluene using a paint shaker.
• a 60 ⁇ m-thick triacetyl cellulose film (TAC film, TG60 manufactured by Fujifilm Corporation) was used as the transparent substrate.
• the composition for forming an antiglare layer was applied to one surface of the transparent substrate using a bar coater, and dried in a dryer at 100° C. for 1 minute. In a nitrogen atmosphere (oxygen concentration 500 ppm or less), the composition was UV-cured using a high-pressure mercury UV device so that the cumulative exposure amount was 200 mJ/cm 2 , forming an antiglare layer with a thickness of 5 ⁇ m.
• Example 2 As organic fine particles, 5.0 parts by mass of organic fine particles (refractive index 1.49) having an average particle size of 3 ⁇ m and 5.0 parts by mass of organic fine particles (refractive index 1.59) having an average particle size of 5.0 ⁇ m were used, and no organic clay was added. The amount of organic fine particles and the amount of organic clay changed from Example 1 were adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, the composition for forming an antiglare layer was adjusted to be the same as in Example 1. Using the adjusted composition for forming an antiglare layer, an antiglare layer having a thickness of 8 ⁇ m was formed on one surface of a transparent substrate in the same manner as in Example 1.
• Example 3 As organic fine particles, 8.0 parts by mass of organic fine particles having an average particle size of 5 ⁇ m (refractive index 1.49) and 10.0 parts by mass of organic fine particles having an average particle size of 5.0 ⁇ m (1.59) were used, and no organic clay was added. The amount of organic fine particles and the amount of organic clay changed from Example 1 were adjusted by reducing the amount of pentaerythritol triacrylate so that the total of the solid content other than the solvent was 100 parts by mass. Except for the above conditions, a composition for forming an antiglare layer was prepared in the same manner as in Example 1. The prepared composition for forming an antiglare layer was used to form an antiglare layer having a thickness of 8 ⁇ m on one surface of a transparent substrate.
• Example 4 [Low refractive index layer forming composition] 45.0 parts by mass of PETA, 50 parts by mass of hollow silica microparticles dispersed in isopropyl alcohol having an average particle size of 75 nm in terms of solid content, and 3.0 parts by mass of a photopolymerization initiator were added, and 2.0 parts by mass of a fluorine-based antifouling agent (KY-1203, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added, and the mixture was diluted with an isopropyl alcohol solvent so that the total solid content was 3.5 parts by mass, and stirred for 40 minutes with a paint shaker to obtain a composition for forming a low refractive index layer.
• a fluorine-based antifouling agent KY-1203, manufactured by Shin-Etsu Chemical Co., Ltd.
• An antiglare layer was formed on one surface of the transparent substrate in the same manner as in Example 1.
• the composition for forming a low refractive index layer was applied to the surface of the antiglare layer using a bar coater, and dried in a dryer at 100° C. for 1 minute.
• a high-pressure mercury UV device was used in a nitrogen atmosphere (oxygen concentration 500 ppm or less) to perform UV curing so that the cumulative exposure amount was 200 mJ/cm 2 , and a low refractive index layer was formed so that the optical film thickness nd (refractive index n ⁇ film thickness d) was 550/4 nm.
• Example 5 Except for using 5.0 parts by mass of organic fine particles (refractive index 1.59) having an average particle size of 3 ⁇ m as the organic fine particles, an antiglare layer was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the antiglare layer in the same manner as in Example 4.
• Example 6 Except for using 5.0 parts by mass of organic fine particles (refractive index 1.49) having an average particle size of 1.5 ⁇ m as the organic fine particles, an antiglare layer having a thickness of 3 ⁇ m was formed on one surface of a transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the antiglare layer in the same manner as in Example 4.
• Example 7 Except for using 5.0 parts of organic fine particles (refractive index 1.59) having an average particle size of 10.0 ⁇ m as the organic fine particles, an antiglare layer having a thickness of 12 ⁇ m was formed on one surface of a transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the antiglare layer in the same manner as in Example 4.
• Example 8 As the organic fine particles, 12.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 0.8 ⁇ m were used, and the amount of the organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a film thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 9 As organic fine particles, 5.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 2.0 ⁇ m and 2.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 2.0 ⁇ m were used, and the amount of organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a film thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 10 As organic fine particles, 12.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 2.0 ⁇ m and 3.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 3.0 ⁇ m were used, and the amount of organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a film thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 11 As organic fine particles, 8.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 3.0 ⁇ m and 2.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 3.0 ⁇ m were used, and the amount of organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a film thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 12 As the organic fine particles, 10.0 parts by mass of organic fine particles (refractive index 1.59) having an average particle size of 3.0 ⁇ m was used, and the amount of the organic fine particles was changed from that of Example 1 by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer having a thickness of 5 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 13 As the organic fine particles, 8.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 5.0 ⁇ m were used, and the amount of the organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a thickness of 6 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Comparative Example 1 As the organic fine particles, 15.0 parts by mass of organic fine particles (refractive index 1.59) having an average particle size of 8.0 ⁇ m were used, and the amount of the organic fine particles was changed from that in Example 1 by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was adjusted to 100 parts by mass. Except for the above conditions, an antiglare layer having a thickness of 5 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1.
• Comparative Example 2 The organic fine particles were changed to 2.0 parts by mass of organic fine particles (refractive index 1.49) having an average particle size of 3.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted by increasing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer having a thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1.
• Example 3 The organic fine particles were changed to 2.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 0.8 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by increasing the amount of pentaerythritol triacrylate. Except for the above conditions, an antiglare layer with a thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 4 The organic fine particles were changed to 2.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 1.5 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted by increasing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 5 The organic fine particles were changed to 2.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 2.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted by increasing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a film thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 6 The organic fine particles were changed to 15.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 2.0 ⁇ m, and 5.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 2.0 ⁇ m.
• the amount of the organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a thickness of 5 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 7 The organic fine particles were changed to 8.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 3.0 ⁇ m, and 8.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 3.0 ⁇ m.
• the amount of the organic fine particles changed from Example 1 was adjusted by reducing the amount of pentaerythritol triacrylate so that the total solid content other than the solvent was 100 parts by mass. Except for the above conditions, an antiglare layer with a thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 8 The organic fine particles were changed to 10.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 5.0 ⁇ m, and 2.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 5.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by reducing the amount of pentaerythritol triacrylate. Except for the above conditions, an antiglare layer with a thickness of 6.5 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 9 The organic fine particles were changed to 8.0 parts by mass of organic fine particles (refractive index 1.49) with an average particle size of 15.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by reducing the amount of pentaerythritol triacrylate. Except for the above conditions, an antiglare layer with a thickness of 17 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 10 (Comparative Example 10) The organic fine particles were changed to 12.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 3.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by reducing the amount of pentaerythritol triacrylate. Except for the above conditions, an antiglare layer with a thickness of 4 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 11 The organic fine particles were changed to 12.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 5.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by reducing the amount of pentaerythritol triacrylate. Except for the above conditions, HC composition 1 was prepared in the same manner as in Example 1, and an antiglare layer with a thickness of 6.5 ⁇ m was formed in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• Example 12 The organic fine particles were changed to 12.0 parts by mass of organic fine particles (refractive index 1.59) with an average particle size of 10.0 ⁇ m, and the amount of the organic fine particles changed from Example 1 was adjusted to 100 parts by mass by reducing the amount of pentaerythritol triacrylate. Except for the above conditions, an antiglare layer with a thickness of 12 ⁇ m was formed on one surface of the transparent substrate in the same manner as in Example 1. Next, a low refractive index layer was formed on the above antiglare layer in the same manner as in Example 4.
• ⁇ Evaluation 1 Surface irregularity> (Acquisition of 3D data) Using a Vertscan (R3300H Lite, manufactured by Ryoka Systems Co., Ltd.), three-dimensional data of the uneven shape of the outermost surface of the optical laminate was measured by an optical interference method. The measurement conditions were as follows. The unevenness height was based on the lowest position within the measurement range.
• ⁇ Camera model Sony HR-50 1/3 ⁇ Objective lens magnification: 5XTI ⁇ Telescope tube: 1X Zoom lens: 1X ⁇ Light source: 530white Wavelength filter: 520 nm
• Measurement device Piezo Measurement mode: Phase Scan speed: 4 ⁇ m/sec ⁇ Scan range: 10 ⁇ m to -10 ⁇ m Effective pixels: 0% Measurement range: 940.8 ⁇ m x 705.6 ⁇ m, 640 pixels x 480 pixels ⁇ XY direction resolution: 1 pixel 1.47 ⁇ m
• FFT analysis FFT analysis was performed using the free software "ImageJ 1.53h" under Windows 10. The procedure is as follows. 1. The three-dimensional data was converted into TIFF image data in which height is the pixel value. 2. FFT was performed with reference to the original 3D data values (height measurements). The image size after FFT processing was 1024 pixels x 1024 pixels. 3. The image after FFT processing was subjected to a process of restoring the power spectrum intensity to an actual measured value. 4. In the processed image, a range of ⁇ 20 pixels on the positive X-axis passing through the origin was specified, and the power spectrum intensity was output. 5. The X-coordinate of the output power spectrum was converted to spatial frequency f based on the pixel size of the original three-dimensional data. 6. From the calculated spatial frequency, the average values (values A and B) of the antilogarithm of the power spectrum intensity within each range of 50 cycle/mm ⁇ f ⁇ 100 cycle/mm and 200 cycle/mm ⁇ f ⁇ 250 cycle/mm were calculated.
• the FFT of the above three-dimensional data is a process for decomposing the waves resulting from the change in surface height of the optical film into spatial frequency components.
• a grayscale image may be generated from the above three-dimensional data, in which the height information is expressed as a predetermined level of brightness.
• the grayscale image can be generated by converting the height information into a numerical value that represents 256 levels of brightness, with a minimum value of 0 and a maximum value of 255.
• a two-dimensional Fourier transform is performed on the obtained grayscale image.
• the power spectrum intensity obtained by the two-dimensional Fourier transform is subjected to a transform that is the reverse of the transform from the height information to brightness, thereby restoring the power spectrum intensity to a value corresponding to the height. This results in data obtained by applying a fast Fourier transform to the height information of the unevenness at each position on the surface of the optical film 10.
• step 1 above conversion to values representing brightness may not be performed, and in step 2 above, a two-dimensional Fourier transform may be performed on the height information itself.
• the number of data points in the three-dimensional data there are no particular limitations on the number of data points in the three-dimensional data, the number of pixels in the grayscale image, and the number of pixels in the FFT image, which is the power spectrum.
• the 480 rows of height data are decomposed into 1024 frequencies for each row, and then the data is transposed vertically and horizontally, and the 640 columns of height data are decomposed into 1024 frequencies for each column. This results in a 1024px x 1024px FFT image.
• the "FFT of (file name)” image is an image in which the power spectrum intensity is normalized to 256 levels of light and dark
• the "PS of (file name)” image is an image in which the power spectrum intensity is a value corresponding to the height of the three-dimensional data.
• the color difference ⁇ E*ab before and after the olive oil was attached was calculated, and the fingerprint wiping property was evaluated according to the following criteria based on the number of wipings until the color difference ⁇ E*ab became 0.5 or less. 5 (very good): Number of wipes ⁇ 9 times 4 (fairly good): Number of wipes ⁇ 12 times 3 (good): Number of wipes ⁇ 12 times 2 (not very good): Number of wipes ⁇ 15 times 1 (bad): Number of wipes ⁇ 20 times
• the measurement conditions for the reflectance spectrum are as follows: Measurement diameter: ⁇ 8mm ⁇ Item: SCI/SCE Light source: D65 UV setting: 100% Observation field of view: 10°
• Glare evaluation> The obtained optical laminate was placed on a metal mask of six types of grating patterns (85, 106, 127, 169, 254, 508 ppi) with different resolution, and the glare contrast was measured by single-image measurement using a glare meter SMS-1000 (manufactured by DM&S) (in accordance with JIS C1006:2019).
• the horizontal axis represents resolution and the vertical axis represents glare contrast, and the measured values of the resolution and glare contrast of the metal mask used were plotted to calculate the slope a of the linear approximation equation. Based on the calculated value of a, the glare resistance was evaluated according to the following criteria. ⁇ (very good): 0 ⁇ a ⁇ 0.010 ⁇ (Good): 0.010 ⁇ a ⁇ 0.015 ⁇ (bad): 0.015 ⁇ a
• FIG. 3 is a diagram showing a method for evaluating the antiglare property
• FIG. 4 is a diagram showing an example of the evaluation of the antiglare property.
• the obtained optical laminate was attached to a blackboard with an optical adhesive so that the functional surface was the surface.
• a three-wavelength fluorescent lamp and the optical laminate were placed so that light was perpendicular to the functional surface.
• the surface of the optical laminate was observed from a direction in which the line connecting the viewpoint and the image of the three-wavelength fluorescent lamp reflected on the functional surface was 70° to the perpendicular line from the three-wavelength fluorescent lamp to the functional surface, and the antiglare property was evaluated according to the following criteria (see FIG. 4).
• ⁇ The outline of the three-wavelength fluorescent lamp is clear and the edges are visible but blurred.
• ⁇ The outline of the three-wavelength fluorescent lamp is clear, but the edges are blurred and unclear.
• ⁇ The outline of the three-wavelength fluorescent lamp is so blurred that it is impossible to see, or the edges are clearly visible.
• ⁇ HAZE> The haze was measured using a haze meter (NDH7000, manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with the haze test method of JIS K 7136, which is a test method for optical properties of plastics.
• the anti-glare properties evaluated based on the slope a of the approximation line indicate that anti-glare properties are unlikely to deteriorate even if the resolution of the display device increases.
• the present invention can be used as an optical film that is placed on the outermost surface of an image display device.

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