JP2019184772A - Anti-glare film - Google Patents

Abstract

An anti-glare method capable of reducing a haze value by smoothing the surface of a film, suppressing a decrease in sharpness of an image displayed on a high-resolution display, and suppressing reflection of external light on the display surface. The purpose is to provide a functional film. One embodiment of the present invention includes a base material, and a coat layer laminated on one surface of the base material. The coat layer includes a binder and organic fine particles dispersed in the binder. An antiglare film having organic fine particles having a CV value of less than 15%. The organic fine particles preferably have a particle size of 5 μm or less. The difference between the refractive index of the binder and the refractive index of the organic fine particles is preferably 0.1 or less. The material of the base material is preferably polyethylene terephthalate or acrylic. [Selection diagram] Fig. 1

Description

  The present invention relates to an antiglare film.

  Liquid crystal display devices are widely used as displays by taking advantage of their features such as thinness, light weight, and low power consumption, and their applications have expanded to mobile information terminals such as TVs, personal computers and smartphones, and portable information terminals such as tablet terminals. Higher brightness and higher resolution are advancing rapidly.

  In such a high-performance display, an anti-glare film may be used for suppressing external light from being reflected on the screen and reducing visibility. As such a film, an anti-glare layer is formed on one of the transparent substrates by coating a light-transmitting resin with a light-transmitting diffusing agent such as resin beads to form an anti-glare layer. An anti-glare film that can prevent a decrease in contrast, surface glare (fine brightness variation), reflection, and whitening by setting the value to 7 to 30 and the internal haze value to 1 to 15 has been proposed. (JP-A-11-305010).

  This anti-glare film increases the external haze value by forming minute irregularities that diffuse light on the film surface in order to prevent external light from being reflected on the display. There is a risk of impairing the clarity of the image on the display. Further, high brightness and high resolution displays tend to have strong surface glare, and it is necessary to increase the internal haze in order to prevent this strong surface glare. However, if the internal haze is increased, the sharpness is further deteriorated, so that the original performance of the high-performance display may not be exhibited.

Japanese Patent Laid-Open No. 11-305010

  The present invention has been made in view of such circumstances, and smoothes the surface of the film to reduce the haze value, suppresses a decrease in the sharpness of the image displayed on the high-resolution display, and externally on the surface. An object of the present invention is to provide an antiglare film capable of suppressing reflection of light.

  One embodiment of the present invention made to solve the above problems includes a base material and a coating layer laminated on one surface of the base material, and the coating layer is dispersed in the binder and the binder. And an organic anti-glare film having a CV value of less than 15%.

The antiglare film has a binder and organic fine particles dispersed in the binder in a coating layer laminated on the base material, and the organic fine particles have a CV (coefficient of variation) value of less than 15%. Therefore, by forming the coat layer thicker than the average particle diameter of the organic fine particles, it is possible to prevent the unevenness due to the organic fine particles from being formed on the surface of the coat layer. Accordingly, the film surface can be easily smoothed, and the haze value can be reduced, thereby suppressing a reduction in the sharpness of the image of the high-resolution display. Moreover, since the said organic fine particle has light-scattering property, the reflection of this external light can be suppressed by scattering the external light which injects from the said anti-glare film surface. In addition, CV value is a particle size distribution, and is calculated | required by following formula (1).

  The particle size of the organic fine particles is preferably 5 μm or less. When the particle diameter of the organic fine particles is 5 μm or less, the thickness of the coat layer can be easily reduced.

  The difference between the refractive index of the binder and the refractive index of the organic fine particles is preferably 0.1 or less. By making the difference between these refractive indexes 0.1 or less, the coat layer can be made excellent in transparency.

  The material of the substrate is preferably polyethylene terephthalate or acrylic. Polyethylene terephthalate and acrylic are suitable as a base material for an antiglare film because they are excellent in transparency and flexibility, and are excellent in affinity with the coating layer.

  As described above, the antiglare film of the present invention can reduce the haze value and suppress the reflection of external light while suppressing the decrease in the sharpness of the image of the high resolution display.

It is typical sectional drawing which shows the anti-glare film which concerns on one Embodiment of this invention. It is a graph which shows the change of the haze value at the time of changing the thickness of the coating layer of the anti-glare film which concerns on the Example of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[Anti-glare film]
The antiglare film 1 of FIG. 1 includes a base material 2 and a coat layer 3 laminated on the base material 2. The coat layer 3 has a binder 4 and organic fine particles 5 dispersed in the binder 4. One surface of the substrate 2 is in contact with a display, a polarizing plate, etc. (not shown), and the coat layer 3 is laminated on the other surface.

<Base material>
The base material layer 2 is formed mainly of a transparent, particularly colorless and transparent synthetic resin, in order to transmit light. The main component of the substrate 2 is not particularly limited, and examples thereof include polyethylene terephthalate, polyethylene naphthalate, acrylic resin, polycarbonate, polystyrene, polyolefin, cellulose acetate, and weather resistant vinyl chloride. Among them, polyethylene terephthalate or acrylic excellent in transparency is preferable, and polyethylene terephthalate having high strength and being difficult to bend is particularly preferable. The “main component” refers to a component having the highest content, for example, a component having a content of 50% by mass or more.

  As a minimum of average thickness of substrate 2, 10 micrometers is preferred, 20 micrometers is more preferred, and 30 micrometers is still more preferred. On the other hand, the upper limit of the average thickness of the substrate 2 is preferably 500 μm, more preferably 250 μm, and even more preferably 100 μm. If the average thickness of the substrate 2 is less than the above lower limit, curling may occur when the coating layer 3 is formed by coating. On the other hand, when the average thickness of the substrate 2 exceeds the above upper limit, the luminance of the display may be lowered, and the demand for thinning the display may not be met. Note that “average thickness” refers to an average value of thicknesses at arbitrary 10 points.

<Coat layer>
The coat layer 3 is formed on one surface of the substrate 2 and constitutes the surface of the antiglare film 1. The coat layer 3 includes a binder 4 and organic fine particles 5 dispersed in the binder 4. The coat layer 3 contains organic fine particles 5 in a dispersed manner at substantially equal density. Since the organic fine particles 5 are embedded in the coat layer 3, the surface of the coat layer 3 is smoothed with almost no unevenness.

  The lower limit of the average thickness of the coat layer 3 is 2 μm, more preferably 2.5 μm, and still more preferably 3 μm. On the other hand, the upper limit of the average thickness of the coat layer 3 is 8 μm, more preferably 7 μm, and further preferably 6 μm. If the average thickness of the coat layer 3 is less than the lower limit, irregularities are formed on the surface of the coat layer 3 and external haze may occur. On the other hand, when the average thickness of the coat layer 3 exceeds the above upper limit, the luminance of the display may be lowered, and when the coat layer 3 is formed by coating, the base material 2 may be curled. is there.

  More specifically, the average thickness of the coat layer 3 is preferably substantially the same as the average particle diameter of the organic fine particles 5 described later. By doing in this way, generation | occurrence | production of the curl of the base material 2 can be suppressed, suppressing formation of an unevenness | corrugation in the surface of the coat layer 3. FIG. The ratio of the average thickness of the coat layer 3 to the average particle diameter of the organic fine particles 5 is preferably 0.95, more preferably 1.1, and even more preferably 1.25. On the other hand, the upper limit of the ratio is preferably 2, more preferably 1.7, and still more preferably 1.4. If the ratio of the average thickness of the coat layer 3 to the average particle diameter of the organic fine particles 5 is less than the lower limit, irregularities are formed on the surface of the coat layer 3 and external haze may occur. On the other hand, if the ratio exceeds the upper limit, the luminance of the display may be lowered, and when the coat layer 3 is formed by coating the base material 2, the base material 2 may be curled. is there.

(binder)
The binder 4 is formed with a transparent, particularly colorless and transparent synthetic resin as a main component in order to transmit light. Examples of the synthetic resin include a thermosetting resin and an active energy ray curable resin. Among these, as the synthetic resin, an active energy ray curable resin excellent in holding the organic fine particles 5 is preferable.

  Examples of the thermosetting resin include epoxy resins, silicone resins, phenol resins, urea resins, unsaturated polyester resins, melamine resins, alkyd resins, polyimide resins, acrylic resins, amide functional copolymers, urethane resins, and the like. It is done.

  Examples of the active energy ray curable resin include an ultraviolet curable resin that is crosslinked and cured by irradiating ultraviolet rays, and an electron beam curable resin that is crosslinked and cured by irradiating an electron beam. In addition, it can be appropriately selected from polymerizable oligomers. Among them, the active energy ray-curable resin is an acrylic, urethane, or acrylurethane ultraviolet curable resin that improves adhesion to the substrate 2 and easily prevents the organic fine particles 5 from falling off the coating layer 3. Is preferred.

  As the polymerizable monomer, a (meth) acrylate monomer having a radical polymerizable unsaturated group in the molecule is preferably used, and among them, a polyfunctional (meth) acrylate is preferable. The polyfunctional (meth) acrylate is not particularly limited as long as it is a (meth) acrylate having two or more ethylenically unsaturated bonds in the molecule. Specifically, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified diphosphate (Meth) acrylate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylo Propropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, tris (acrylic) Roxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide modified dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol hexa (meth) acrylate, etc. Can be mentioned. These polyfunctional (meth) acrylates may be used singly or in combination of two or more. Among these, dipentaerythritol tri (meth) acrylate is preferable.

  In addition to the polyfunctional (meth) acrylate, a monofunctional (meth) acrylate may be further included for the purpose of reducing the viscosity. Examples of the monofunctional (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl ( Examples include meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and isobornyl (meth) acrylate. These monofunctional (meth) acrylates may be used alone or in a combination of two or more.

  Examples of the polymerizable oligomer include oligomers having radically polymerizable unsaturated groups in the molecule, such as epoxy (meth) acrylate oligomers, urethane (meth) acrylate oligomers, polyester (meth) acrylate oligomers, and polyethers. Examples include (meth) acrylate oligomers.

  The epoxy (meth) acrylate oligomer can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin and esterifying it. It is also possible to use a carboxyl-modified epoxy (meth) acrylate oligomer obtained by partially modifying the epoxy (meth) acrylate oligomer with a dibasic carboxylic acid anhydride. The urethane (meth) acrylate oligomer can be obtained, for example, by esterifying a polyurethane oligomer obtained by a reaction of polyether polyol or polyester polyol with polyisocyanate with (meth) acrylic acid. The polyester (meth) acrylate oligomer can be obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid. . Moreover, the said polyester (meth) acrylate type oligomer can also be obtained by esterifying the hydroxyl group of the terminal of the oligomer obtained by providing alkylene oxide to polyhydric carboxylic acid with (meth) acrylic acid. The polyether (meth) acrylate oligomer can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid.

  As the active energy ray curable resin, an ultraviolet curable epoxy resin is also preferably used. Examples of the ultraviolet curable epoxy resin include cured products such as bisphenol A type epoxy resin and glycidyl ether type epoxy resin. Since the main component of the binder 4 is an ultraviolet curable epoxy resin, the anti-glare film 1 can easily smooth the surface of the substrate 2 by suppressing volume shrinkage during curing. Moreover, the said anti-glare film 1 can improve the softness | flexibility of the binder 4 because the main component of the binder 4 is an ultraviolet curable epoxy resin. Further, when an ultraviolet curable epoxy resin is used as the active energy ray curable resin, it is preferable not to include other polymerizable monomers and polymerizable oligomers such as the (meth) acrylate monomer and (meth) acrylate oligomer. . Thereby, the softness | flexibility of the binder 4 can further be improved.

  When an ultraviolet curable resin is used as the active energy ray curable resin, it is desirable to add a photopolymerization initiator in an amount of 0.1 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the resin. The initiator for photopolymerization is not particularly limited. For a polymerizable monomer or polymerizable oligomer having a radical polymerizable unsaturated group in the molecule, for example, benzophenone, benzyl, Michler's ketone, 2-chlorothioxanthone. 2,4-diethylthioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-diethoxyacetophenone, benzyldimethyl ketal, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2, -Hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1, 1- [4 -(2-hydroxyethoxy) Phenyl] -2-hydroxy-2-methyl-1-propan-1-one, bis (cyclopentadienyl) -bis [2,6-difluoro-3- (pyrrol-1-yl) phenyl] titanium, 2- Examples include benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2,4,6-trimethylbenzoyldiphenylphosphine oxide. Examples of the polymerizable oligomer having a cationic polymerizable functional group in the molecule include aromatic sulfonium salts, aromatic diazonium salts, aromatic iodonium salts, metallocene compounds, and benzoin sulfonic acid esters. These compounds may be used alone or in combination.

  In addition, the binder 4 can also contain an additive in addition to the synthetic resin. Examples of the additive include a silicone-based additive, a fluorine-based additive, and an antistatic agent. Moreover, as solid content conversion content of the said additive with respect to 100 mass parts of said synthetic resin components of the binder 4, it is 0.05 mass part or more and 5 mass parts or less, for example.

  The refractive index of the refractive index of the binder 4 is preferably 1.4 as the lower limit, and more preferably 1.45. On the other hand, the upper limit of the refractive index of the binder 4 is preferably 1.55, and more preferably 1.5. When the refractive index of the binder 4 exceeds the above range, the difference in refractive index from the base material 2 becomes large, and the transparency of the antiglare film 1 may be lowered. The “refractive index” refers to the refractive index of light having a wavelength of 589.3 nm (sodium D-line).

(Organic fine particles)
The organic fine particles 5 are transparent, particularly colorless and transparent organic fine particles having a property of transmitting and diffusing light. Examples of the organic fine particles include organic fine particles such as styrene resins, styrene-acrylic copolymer resins, and acrylic resins synthesized by an emulsion polymerization method. The organic fine particles are synthesized by an emulsion polymerization method, and by adding a crosslinking agent, variation in particle diameter can be suppressed and a desired refractive index can be obtained.

  The organic fine particles 5 can also be resin particles formed with a synthetic resin as a main component. Examples of the main component of the resin particles include acrylic resin, acrylonitrile resin, polyurethane, polyvinyl chloride, polystyrene, polyamide, and polyacrylonitrile. Among them, an acrylic resin having high transparency is preferable, and polymethyl methacrylate (PMMA) is particularly preferable.

  The shape of the organic fine particle 5 is not particularly limited, and examples thereof include a spherical shape, a cubic shape, a needle shape, a rod shape, a spindle shape, a plate shape, a scale shape, and a fiber shape, and among them, a spherical shape having excellent light diffusibility. Is preferred.

  The lower limit of the average particle diameter of the organic fine particles 5 is preferably 1 μm and more preferably 2 μm. On the other hand, the upper limit of the average particle diameter of the organic fine particles 5 is preferably 5 μm, and more preferably 4 μm. If the average particle diameter is less than the lower limit, the organic fine particles 5 may not be completely crushed when the binder 4 and the organic fine particles 5 are mixed and stirred. On the other hand, when the average particle diameter exceeds the above upper limit, the haze value may increase and the visibility of the display may decrease. The average particle diameter refers to the diameter of a single particle that has not been agglomerated, and the spherical average is the diameter of the particle, and the non-spherical average is the arithmetic average value of the major axis diameter and the minor axis diameter. This is measured by an electron microscope.

  The organic fine particles 5 are preferably monodisperse particles, and the CV value (variation coefficient) of the particle diameter of the organic fine particles 5 is less than 15%. The upper limit of the CV value is preferably 13%, more preferably 11%, further preferably 10%, and particularly preferably 8%. If the coefficient of variation exceeds the upper limit, irregularities are formed on the surface of the coat layer 3 and external haze may occur.

  The refractive index of the organic fine particles 5 is preferably 1.4 as the lower limit, and more preferably 1.45. On the other hand, the upper limit of the refractive index of the organic fine particles 5 is preferably 1.55, and more preferably 1.5. If the refractive index of the organic fine particles 5 exceeds the above range, the difference in refractive index from the binder 4 becomes large, and there is a possibility that luminance unevenness of the display cannot be suppressed.

  The difference in refractive index between the organic fine particles 5 and the binder 4 in the coat layer 3 is preferably 0.1 as an upper limit, more preferably 0.05, and particularly preferably 0.001. When the refractive index difference exceeds the above upper limit, there is a possibility that luminance unevenness of the display cannot be suppressed.

  The upper limit of the arithmetic average roughness Ra of the surface of the coat layer 3 is preferably 0.05 μm, more preferably 0.04 μm, and further preferably 0.03 μm. If the arithmetic average roughness Ra of the surface of the coat layer 3 exceeds the above upper limit, the external haze value may increase due to the unevenness of the surface of the coat layer 3. “Arithmetic mean roughness Ra” means a value measured according to JIS-B0601: 2001.

  The upper limit of the ten-point average roughness Rzjis on the surface of the coat layer 3 is preferably 0.6 μm, more preferably 0.55 μm, and even more preferably 0.5 μm. If the ten-point average roughness Rzjis on the surface of the coat layer 3 exceeds the above upper limit, the external haze value may increase due to the unevenness on the surface of the coat layer 3. The “ten-point average roughness Rzjis” means a value measured according to JIS-B0601: 2001.

  The upper limit of the root mean square roughness Rq of the surface of the coat layer 3 is preferably 0.05 μm, more preferably 0.04 μm, and even more preferably 0.03 μm. If the root mean square roughness Rq of the surface of the coat layer 3 exceeds the above upper limit, the external haze value may increase due to the unevenness of the surface of the coat layer 3. “Root mean square roughness Rq” means a value measured according to JIS-B0601: 2001.

As a minimum of the amount of lamination (in solid content conversion) of coat layer 3, 2.4 g / m ² is preferred, 3.0 g / m ² is more preferred, and 3.6 g / m ² is still more preferred. In contrast, the upper limit of the stacked amount of the coating layer 3, preferably 9.6 g / ^{m 2,} more preferably 8.4 g / ^{m 2,} more preferably 7.2 g / ^{m 2.} If the amount of the coat layer 3 is less than the lower limit, the organic fine particles 5 cannot be accurately fixed by the binder 4, and the organic fine particles 5 may fall off the coat layer 3. On the other hand, when the lamination amount of the coat layer 3 exceeds the above upper limit, the thickness of the coat layer 3 is increased, cracks may occur in the coat layer 3, and curling occurs in the antiglare film 1, When the antiglare film 1 is cut, the coat layer 3 may be cracked.

  As a minimum of the content rate of the organic fine particle 5 in the coating layer 3, 0.75 mass% is preferable and 0.84 mass% is more preferable. On the other hand, the upper limit of the content of the organic fine particles 5 in the coat layer 3 is preferably 2% by mass, more preferably 1.8% by mass, and even more preferably 1.64% by mass. If the content of the organic fine particles 5 in the coat layer 3 is less than the lower limit, the antiglare property of the antiglare film 1 may not be exhibited. On the other hand, if the content of the organic fine particles 5 in the coat layer 3 exceeds the upper limit, the brightness of the display of the coat layer 3 may be lowered.

  The upper limit of the haze value of the antiglare film 1 is preferably 2%, more preferably 1.5%, and further preferably 1%. When the haze value of the anti-glare film 1 exceeds the above upper limit, the sharpness of the display may be reduced. The “haze value” means a value measured according to JIS-K7361: 2000.

<Advantages>
In the antiglare film 1, the coating layer 3 has the binder 4 and the organic fine particles 5, but the CV value of the organic fine particles 5 is less than 15%, and thus the surface of the coating layer 3 is caused by the organic fine particles 5. Unevenness is not formed. Therefore, since the anti-glare film 1 does not diffuse the light incident from the back side due to the unevenness, it does not deteriorate the sharpness of the high-resolution display. In addition, since the organic fine particles 5 have light scattering properties, the organic fine particles 5 can exhibit suitable anti-glare properties for light incident from the back side of the anti-glare film and scatter external light incident from the front side. Therefore, the reflection of external light can be suppressed.

  Since the organic fine particles 5 of the antiglare film 1 have a CV value of less than 15%, the surface of the coat layer 3 is smoothed only by making the thickness of the coat layer slightly larger than the average particle diameter of the organic fine particles 5. be able to. Therefore, the coat layer 3 can be formed thin, and the occurrence of cracks in the coat layer 3 can be suppressed. Moreover, the occurrence of curling of the antiglare film 1 can be suppressed, and the occurrence of cracks in the coat layer 3 can be suppressed when the antiglare film 1 is cut.

<Method for producing antiglare film>
As the manufacturing method of the said anti-glare film 1, the process (base material layer formation process) which forms the sheet body which comprises the base material 2, and the process of laminating | coating the coating layer 3 on the one surface side of this sheet body ( Coating layer laminating step).

(Base material layer forming step)
The base material layer forming step is not particularly limited. For example, a molten thermoplastic resin is extruded from a T die, and then the extruded body is stretched in the layer longitudinal direction and the layer width direction to form a sheet body. The method of doing is mentioned. As a known extrusion molding method using a T-die, for example, a polishing roll method and a chill roll method can be cited. Examples of the method for stretching the sheet include a tubular film biaxial stretching method and a flat film biaxial stretching method.

(Coat layer lamination process)
The coating layer laminating step includes a step of preparing a coating solution containing the binder 4 and the organic fine particles 5 (preparation step), and a step of applying the coating solution prepared in the preparation step to one surface side of the sheet body. (Application process) and a process (curing process) for drying and curing the coating liquid applied in the application process. In the preparation step, it is preferable to prepare a coating liquid containing the active energy ray-curable resin as the main component of the binder 4 and the organic fine particles 5. The manufacturing method of the anti-glare film uses an active energy ray-curable resin as a main component of the binder 4, and after applying the coating liquid in the application process, the ultraviolet light is irradiated, for example, in the curing process. It is easy to cure the energy ray curable resin relatively quickly.

  In addition, the manufacturing method of the said anti-glare film is a corona discharge treatment, an ozone treatment, a low temperature plasma treatment, an ultraviolet irradiation treatment, a glow treatment on the surface of the sheet body on which the coat layer is laminated before the coating layer lamination step. A surface treatment step for performing a discharge treatment, an oxidation treatment, a primer coat treatment, an undercoat treatment, an anchor coat treatment or the like may be further provided.

[Other Embodiments]
In addition, the anti-glare film which concerns on this invention can be implemented with the aspect which gave various change and improvement other than the said aspect. For example, the anti-glare film can be a film that includes an adhesive layer on the back side and can be attached to the display surface or the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

  The substrate used was an average thickness of 75 μm mainly composed of polyethylene terephthalate. As the coating layer, a refractive index of 1.5 and a fine particle of organic fine particles (beads) of 1.67% by mass are blended in a binder having a refractive index of 1.47 mainly composed of acrylic and 4000 rpm with a mixer. What was stirred for 5 minutes at the rotation speed was applied to one surface of the substrate to obtain antiglare films of Examples 1 to 3 and Comparative Examples 1 and 2. The surface state of the coating layer and the haze value of the antiglare film were confirmed and confirmed by confirmation with a microscope. Table 1 shows other conditions of the antiglare film and the results of evaluation. In addition, "(circle)" in a table | surface shows what was favorable evaluation. “X” indicates that evaluation was not preferable.

  In Comparative Examples 1 and 2, since the CV value of the organic fine particles is 15% or more, some organic fine particles protrude from the surface of the coat layer to form irregularities. In addition, the unevenness caused external haze, which increased the haze value of the antiglare film.

  Using the same base material, binder, and organic fine particles of Example 1, antiglare films of Examples 4 to 5 and Comparative Examples 3 to 4 in which the thickness of the coating layer was changed were obtained. The surface state of the coating layer, the haze value of the antiglare film, the presence or absence of curling, and whether or not the binder suitably holds the organic fine particles in the coating layer were confirmed with a microscope and evaluated. Table 2 shows the thickness of the coating layer and the evaluation results.

  In Comparative Example 3, since the thickness of the coat layer is smaller than the average particle diameter of the organic fine particles, irregularities are formed on the surface of the coat layer, the haze value is increased, and the organic fine particles are suitably held in the coat layer. It wasn't. In Comparative Example 4, curling occurred in the antiglare film because the thickness of the coat layer was too large.

  Using the same base material, binder, and organic fine particles of Example 2, the antiglare films of Example 6 and Comparative Example 5 in which the compounding amount of the organic fine particles was changed as shown in Table 3 were obtained. It was. The change in haze value when the thickness of the coating layer of these antiglare films is changed is shown in FIG.

  In Example 2, it can be seen that when the thickness of the coating layer is about 5.2 μm, the haze value of the antiglare film exceeds 2%, and when the thickness of the coating layer is about 3 μm, the haze value is about 1%. In Example 6, the anti-glare film has a haze value of less than 2% even when the thickness of the coat layer is about 7.5 μm, and the haze value is about 1% even if the thickness of the coat layer is about 4.5 μm. You can see that In Comparative Example 5, the thickness of the coating layer is about 3.3 μm, and the haze value of the antiglare film is about 2%. Since the average particle diameter of the organic fine particles is 3 μm, it can be seen that it is difficult to make the haze value 2% or less.

  As described above, the antiglare film of the present invention suppresses the reflection of external light on the display and does not impair the sharpness of an image displayed at a high resolution. Preferably used.

DESCRIPTION OF SYMBOLS 1 Anti-glare film 2 Base material 3 Coat layer 4 Binder 5 Organic fine particle

Claims (4)

A substrate, and a coat layer laminated on one surface of the substrate;
This coat layer has a binder and organic fine particles dispersed in the binder,
An antiglare film in which the organic fine particles have a CV value of less than 15%.   The antiglare film according to claim 1, wherein the organic fine particles have a particle size of 5 μm or less.   The antiglare film according to claim 1 or 2, wherein a difference between a refractive index of the binder and a refractive index of the organic fine particles is 0.1 or less.   The antiglare film according to claim 1, 2 or 3, wherein the material of the substrate is polyethylene terephthalate or acrylic.

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