Composition for forming color layer

Abstract

In an optical film, the display quality due to external light reflection can be improved, and the life of a light-emitting element of a display device can be extended. [Solution] In the colored layer-forming composition containing an active energy ray-curable resin, a photopolymerization initiator, a dye, and a solvent, the dye contains a first colorant having a maximum absorption wavelength in the range of 470 nm to 530 nm and a half-width of the absorption spectrum of 15 nm to 45 nm, a second colorant having a maximum absorption wavelength in the range of 560 nm to 620 nm and a half-width of the absorption spectrum of 15 nm to 55 nm, and a third colorant having the lowest transmittance in the wavelength range of 400 to 780 nm in the range of 650 nm to 780 nm. An optical film having a 5 μm-thick colored layer formed on a transparent substrate having one or more functional layers using the colored layer-forming composition has a hue value of a * and b * are in the range of -5 to +5 respectively.

Description

[Technical Field]

[0001] The present invention relates to a colored layer-forming composition for forming a colored layer of an optical film. [Background technology]

[0002] Unlike liquid crystal display devices and the like, self-luminous display devices equipped with self-luminous elements such as organic light-emitting elements are excellent in miniaturization and have excellent characteristics such as low power consumption, high brightness, and fast response speed, and are expected to be the next generation of display devices. Metal electrodes and wiring are formed within the display surface area of ​​self-luminous display devices. For this reason, light incident from outside the display screen (i.e., external light) is reflected by the electrodes and wiring, which is likely to cause a decrease in display quality, such as a decrease in contrast.

[0003] To solve the above problems, a configuration has been proposed in which a polarizing plate and a phase retardation plate are arranged on the surface of a self-luminous display device. However, in the configuration using a polarizing plate and a phase retardation plate, when light emitted from the display device passes through the polarizing plate and the phase retardation plate and is emitted to the outside, most of the light is lost, which tends to shorten the life of the device.

[0004] Display devices also require high color purity. Color purity indicates the range of colors that a display device can display, also known as the color reproduction range. Therefore, high color purity means a wide color reproduction range and good color reproducibility. Known methods for improving color reproducibility include using color filters on a light source that emits white light to perform color separation, or using color filters to correct a light source that emits monochromatic light of the three primary colors RGB and narrow the half-value range. However, using color filters to improve the color reproducibility of display devices requires thicker color filters and higher colorant concentrations, which can lead to problems such as poor pixel shape and viewing angle characteristics and reduced display quality. Furthermore, display devices that emit monochromatic light of the three primary colors RGB require a color filter formation process, which increases costs.

[0005] As an example of a display device different from the aforementioned configurations using polarizers and retardation plates or color filters, Patent Document 1 discloses an organic light-emitting display device comprising a display substrate including organic light-emitting elements and an encapsulation substrate spaced apart from the display substrate, with a filler filled in the space between the display substrate and the encapsulation substrate that selectively absorbs external light in each wavelength band and adjusts transmittance. This configuration suppresses external light reflection to improve visibility, and also improves color purity by selectively absorbing light in wavelength bands that particularly reduce color purity among the light emitted from the display device. However, the disclosed technology is insufficient in suppressing external light reflection and suffers from the problem of coloring the reflected light. Furthermore, colorants that absorb light of specific wavelengths have insufficient reliability, such as light resistance, making practical application difficult. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5673713 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the above-described conventional techniques have the following problems. In a device using a polarizing plate and a phase retardation plate, the amount of reflected light due to external light can be reduced, but there is a problem in that the amount of display light generated by the organic light emitting element is also reduced. Furthermore, Patent Document 1 discloses a filler with wavelength-selective absorption that contains a pigment having an absorption maximum in the wavelength range of 480 nm to 510 nm and a pigment having an absorption maximum in the wavelength range of 580 nm to 610 nm. This poses a problem in that it is difficult to eliminate the effects of external light in wavelength ranges below 480 nm and above 610 nm. If external light in these wavelength ranges cannot be suppressed, the reflectance reduction effect is insufficient, and the reflected hue deteriorates. Furthermore, the dyes to which the wavelength-selective absorption properties are imparted are insufficient in reliability, such as light resistance, and it has been difficult to put them into practical use unless the reliability is improved.

[0008] In view of the above circumstances, an object of the present invention is to provide a colored layer-forming composition that can contribute to the production of an optical film that can improve display quality and extend the life of light-emitting elements. [Means for solving the problem]

[0009] The present invention is a colored layer-forming composition containing an active energy ray-curable resin, a photopolymerization initiator, a dye, and a solvent. The dye contains a first coloring material having a maximum absorption wavelength in the range of 470 nm to 530 nm and an absorption spectrum half-width of 15 nm to 45 nm, a second coloring material having a maximum absorption wavelength in the range of 560 nm to 620 nm and an absorption spectrum half-width of 15 nm to 55 nm, and a third coloring material having the lowest transmittance in the wavelength range of 400 to 780 nm and a wavelength in the range of 650 nm to 780 nm. In a layer having a thickness of 5 μm formed using this color layer-forming composition, , the hue value a defined by the following formulas (1) to (9) * and b * are in the range of -5 to +5, respectively.

[0010]

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[0011] Here, λ is a variable representing wavelength, and t is a variable representing the ratio of X, Y, and Z to Xn, Yn, and Zn. a calculated from equations (1) to (3) * , b * is CIE1976L * a * b * It is calculated according to the calculation method for the color space (CIELAB color space). In formulas (1) and (2), Xn, Yn, and Zn are the tristimulus values ​​at the white point of the D65 illuminant. In equation (4), RE(λ) is a function representing the reflectance [%] on a perfectly diffuse reflecting surface (each wavelength 100%), R2(λ) is a function representing the surface reflectance [%] on the outermost surface of the functional layer, and T(λ) is a function representing the transmittance [%] of the optical film. In equations (6) to (9), PD65(λ) is the D65 light source spectrum, and overline x(λ), overline y(λ), and overline z(λ) are color matching functions in a CIE1931 2° visual field. The definite integrals in equations (6) to (9) can be calculated by appropriate numerical integration. The wavelength interval is 1 nm. [Effects of the Invention]

[0012] The present invention can contribute to the production of an optical film that can improve the display quality due to external light reflection and can extend the life of light-emitting elements in a display device. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view illustrating an example of an optical film and a display device according to a first embodiment of the present invention. [Figure 2]2 is a graph showing an example of a light transmission profile of a transparent substrate used in the optical film according to the first embodiment of the present invention. [Figure 3] FIG. 2 is an explanatory diagram of a method for calculating the chromaticness indices a* and b* of the reflection hue of the optical film according to the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view illustrating an example of an optical film and a display device according to a second embodiment of the present invention. [Figure 5] FIG. 10 is a schematic cross-sectional view illustrating an example of an optical film and a display device according to a third embodiment of the present invention. [Figure 6] FIG. 10 is a schematic cross-sectional view showing an example of an optical film and a display device according to a fourth embodiment of the present invention. [Figure 7] 10 is a graph showing a spectrum when white is displayed through an organic EL light source and a color filter in an example. [Figure 8] 10 is a graph showing the spectra of red, green, and blue colors output through an organic EL light source and a color filter in an example. [Figure 9] 10 shows the electrode reflectance of an organic EL display device for calculating display device reflection characteristic 2 and display device reflection hue 2 in the example. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In all drawings, even if the embodiments are different, the same or corresponding components are designated by the same reference numerals, and common descriptions will be omitted.

[0015] [First embodiment] An optical film and a display device according to a first embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing an example of an optical film and a display device according to a first embodiment of the present invention. A display device 50A of this embodiment, the cross section of which in the thickness direction is shown in Fig. 1, displays a color image based on an image signal. The display device 50A includes a display unit 20 and an optical film 10A of this embodiment.

[0016] The display section 20 includes a substrate 21, a light-emitting element 22, and a color filter section . The substrate 21 is formed of, for example, a silicon substrate. The light-emitting element 22 emits white light. For example, an organic EL element may be used as the light-emitting element 22. The organic EL element generates excitons by applying a DC voltage between the anode and the cathode, injecting electrons and holes into the organic light-emitting layer, and causing them to recombine. The organic EL element emits light by utilizing the light emitted when the excitons are deactivated. Light from the light-emitting element 22 is emitted in a light emission direction from the bottom to the top in the figure, centered on an optical axis perpendicular to the organic light-emitting layer. The light emitting element 22 is fabricated on the substrate 21 using, for example, a semiconductor manufacturing process.

[0017] The electrodes of each light-emitting element 22 are connected to a drive circuit (not shown) through metal wiring formed on the substrate 21. The drive circuit controls the turning on and off of each light-emitting element 22 based on an image signal. For example, the light-emitting element 22 is arranged in each pixel that displays color, with a first light-emitting element 22R that is lit in response to a red component image signal, a second light-emitting element 22G that is lit in response to a green component image signal, and a third light-emitting element 22B that is lit in response to a blue component image signal.

[0018] The color filter portion 23 is arranged in the light emitting direction of each light emitting element 22 . The color filter section 23 has a red filter that transmits red light, a green filter that transmits green light, and a blue filter that transmits blue light. The red filter is disposed facing the first light-emitting element 22R, the green filter is disposed facing the second light-emitting element 22G, and the blue filter is disposed facing the third light-emitting element 22B. The color filter section 23 may have lenses that collect light that passes through each of the red filters, each of the green filters, and each of the blue filters.

[0019] The optical film 10A of this embodiment is laminated on the color filter section 23 of the display section 20. The optical film 10A is provided to improve the color purity in the display region of the display section 20 and to suppress degradation of display quality due to external light reflection. The optical film 10A includes, in the light emission direction of the display section 20, a colored layer 12, a transparent substrate 11, a hard coat layer 13, and a low refractive index layer 14A in this order.

[0020] The transparent substrate 11 is a plate or sheet having a first surface 11a and a second surface 11b in the thickness direction. The second surface 11b of the transparent substrate 11 is disposed on the color filter unit 23 side of the display unit 20, with the colored layer 12 sandwiched between them. The visible light transmittance of the material of the transparent substrate 11 is preferably as close to 100% as possible. Here, visible light refers to light in the visible light wavelength band of 380 nm or more and 780 nm or less. Furthermore, the transparent substrate 11 has an ultraviolet absorbing function with an ultraviolet shielding rate of 85% or more, and functions as an ultraviolet absorbing layer for protecting the pigment contained in the colored layer 12 from ultraviolet rays. Here, the ultraviolet shielding rate is measured and calculated based on JIS L 1925, and is expressed as a value [%] obtained by subtracting the average transmittance (unit: [%]) in the wavelength range from 290 nm to 400 nm from 100%.

[0021] Examples of materials that can be used for the transparent substrate 11 include polyolefins such as polyethylene and polypropylene, polyesters such as 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, polyether sulfones, and transparent resins such as polysulfones, and inorganic glass. Among these, films made of polyethylene terephthalate (PET), triacetyl cellulose (TAC), polymethyl methacrylate (PMMA), and polyester films are preferred. The thickness of the transparent substrate 11 is not particularly limited, but is preferably 10 μm to 100 μm. Figure 2 shows the light transmission profiles of transparent substrates made of these materials. In the example shown in Figure 2, the UV blocking rates of each transparent substrate are as follows, and all of them can be used as the transparent substrate 11. TAC: 92.9% PMMA: 93.4% PET: 88.6%

[0022] The ultraviolet absorbing properties of the transparent substrate 11 can be imparted by, for example, blending an ultraviolet absorbing agent into the resin material for forming the transparent substrate 11. The ultraviolet absorbing agent is not particularly limited, but benzophenone-based, benzotriazole-based, triazine-based, oxalic acid anilide-based, and cyanoacrylate-based compounds can be used.

[0023] The colored layer 12 is a layer portion containing a pigment, and is disposed so as to overlap the second surface 11b of the transparent substrate 11. Therefore, the colored layer 12 is disposed between the transparent substrate 11 and the color filter portion 23 side of the display unit 20. The colored layer 12 contains a first color material, a second color material, and a third color material as pigments. The first colorant has a maximum absorption wavelength in the range of 470 nm to 530 nm, and an absorption spectrum with a half-width (full width at half maximum) of 15 nm to 45 nm. Here, the maximum absorption wavelength refers to the wavelength that gives the maximum of the maximum values ​​of light absorptance in the light absorptance spectrum (absorption spectrum). In the light transmittance spectrum, it refers to the wavelength that gives the smallest of the minimum values. The same applies below. The second coloring material has a maximum absorption wavelength in the range of 560 nm to 620 nm, and an absorption spectrum with a half-width of 15 nm to 55 nm. The third coloring material has a wavelength of 650 nm or more and 780 nm or less at which the transmittance is lowest in the wavelength range of 400 to 780 nm. The half width of the absorption spectrum of the third coloring material is, for example, 10 nm or more and 300 nm or less, but is not particularly limited. Hereinafter, the first color material, the second color material, and the third color material may be collectively referred to simply as color materials.

[0024] The first coloring material, second coloring material, and third coloring material contained in the colored layer 12 may contain one or more compounds selected from the group consisting of compounds having any of a porphyrin structure, a merocyanine structure, a phthalocyanine structure, an azo structure, a cyanine structure, a squarylium structure, a coumarin structure, a polyene structure, a quinone structure, a tetradiporphyrin structure, a pyrromethene structure, and an indigo structure, and metal complexes thereof. For example, it is particularly preferable to use a compound having a porphyrin structure, a pyrromethene structure, a phthalocyanine structure, or a squarylium structure in the molecule.

[0025] Furthermore, in the optical film 10A of the present invention, when a D65 light source is irradiated from the surface 10a side, which is the outermost layer of the hard coat layer 13 and the low refractive index layer 14A, which are functional layers on the first surface 11a side of the transparent substrate 11, and when the reflectance R(λ) is measured from the surface 10a side in the case where complete diffuse reflection occurs on the bottom layer 10b side of the optical film, the chromaticness index (value) a of the reflection hue of the optical film represented by the above-mentioned formulas (1) to (9) is * , and b *Each of these hues is in the range of -5 to +5. The hues mentioned above are in one of the uniform color spaces defined by the International Commission on Illumination (CIE 1976L). * a * b * In addition to the above equations (1) and (2), the lightness index L is expressed by the following equation (10): * It is expressed in three-dimensional Cartesian coordinates with the three values ​​of these as axes.

[0026]

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[0027] Here, Y is the tristimulus value of the reflected light at the reflectance R(λ) of the D65 light source, calculated from equations (4), (5), (7), and (9), and Y n are the tristimulus values ​​at the white point of the D65 illuminant.

[0028] Chromaticness index a as an index of the external light reflection hue of the optical film of the present invention * , and b * The calculation method will be explained in detail using FIG.

[0029] When a D65 light source is irradiated from the surface 10a, which is the outermost layer of the functional layer of the optical film 10A in the thickness direction, the light emitted from the optical film 10A can be divided into a surface reflection component and an internal reflection component. The surface reflection component is determined by the surface reflectance at the surface 10a, which is defined by R2(λ) [%]. The internal reflection component is determined by the reflectance R of a perfectly diffuse reflection surface, which is 100% regardless of wavelength. E The reflectance is defined by R1(λ) [%] calculated from the transmittance T(λ) of the optical film 10A and the surface reflectance R2(λ) [%] of the surface 10a using formula (4). When the reflectance of the optical film 10A on the surface 10a irradiated with the D65 light source is R(λ) [%], R(λ) is calculated from the above-mentioned formula (5). Since R(λ), like R1(λ) and R2(λ), is a function of wavelength λ, the tristimulus values ​​X, Y, and Z can be found by calculating the definite integrals with respect to λ in equations (6) to (9). Here, the definite integrals may be found by appropriate numerical integration. For example, when performing numerical integration, the wavelength intervals may be equal, such as 1 nm intervals.

[0030] As described above, X, Y, and Z in the formulas (1) and (2) are tristimulus values ​​of the reflected light at the reflectance R(λ) of the D65 light source on the surface 10a of the optical film 10A, and X n , Y n , Z n represents the tristimulus values ​​at the white point of the D65 light source. From this, the chromaticity index a * and b * From the viewpoint of improving the display quality of the external light reflection, the chromaticity index (value) a of the external light reflection hue of the optical film 10A can be calculated. * and b * It is preferable that each of these is in the range of -5 or more and +5 or less. The internal reflectance generated on the inner surface of the display section or electrode wiring section of a self-luminous display device such as an organic light-emitting display device generally has different values ​​for each wavelength from 380 nm to 780 nm. E (λ) is the reflectance of a perfectly diffuse reflecting surface that is 100% at all wavelengths, and the chromaticity index (value) a of the external light reflection hue of the optical film 10A is * and b * When each of these is within the range of -5 to +5, R E Even when (λ) is replaced with the internal reflectance of the display unit 20 of an actual self-luminous display device, the chromaticity index a * and b * It was found that the value was in the range of -5 to +5, resulting in excellent display quality.

[0031] The colored layer 12 thus configured has maximum absorption wavelengths, i.e., minimum transmittance, in the ranges of 470 nm to 530 nm and 560 nm to 620 nm, and further includes a third colorant whose maximum absorption in the range of 400 nm to 780 nm is in the range of 650 nm to 780 nm, resulting in a spectral absorption spectrum with minimum absorption wavelengths, i.e., maximum transmittance, in the range of 620 nm to 780 nm. Therefore, most of the red, green, and blue light emitted from the display unit 20 is transmitted through the colored layer 12. On the other hand, the amount of transmitted light of wavelength components between the maximum wavelengths of red light and green light, wavelength components between the maximum wavelengths of green light and blue light, ultraviolet light, and part of infrared light is reduced in the colored layer 12. Therefore, for example, among external light reflected by wiring or the like of the display unit 20, wavelength components that reduce the color purity of the display light are absorbed by the colored layer 12.

[0032] The colored layer 12 may contain at least one of a radical scavenger, a peroxide decomposer, and a singlet oxygen quencher as an additive. By containing such an additive, it is possible to suppress fading of the coloring material contained in the colored layer 12 due to light, heat, and the like, and improve durability, as described below.

[0033] For example, radical scavengers capture radicals that occur when a dye undergoes oxidative degradation, inhibiting autoxidation and preventing dye degradation (fading). Using a hindered amine light stabilizer with a molecular weight of 2000 or more as the radical scavenger provides a high level of fading suppression. If the molecular weight of the radical scavenger is low, it is prone to volatilization, resulting in fewer molecules remaining in the colored layer, making it difficult to achieve a sufficient fading suppression effect. Suitable materials for use as radical scavengers include, for example, Chimassorb® 2020FDL, Chimassorb® 944FDL, and Tinuvin® 622 manufactured by BASF, and LA-63P manufactured by ADEKA.

[0034] Peroxide decomposers decompose the peroxides generated when dyes are oxidized and deteriorated, stopping the autoxidation cycle and suppressing dye deterioration (fading). Phosphorus-based antioxidants and sulfur-based antioxidants can be used as peroxide decomposers.

[0035] Examples of phosphorus-based antioxidants include 2,2'-methylenebis(4,6-di-t-butyl-1-phenyloxy)(2-ethylhexyloxy)phosphorus, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, and 6-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-t-butyldibenz[d,f][1,3,2]dioxaphosphepine.

[0036] Examples of sulfur-based antioxidants include 2,2-bis({[3-(dodecylthio)propionyl]oxy}methyl)-1,3-propanediyl-bis[3-(dodecylthio)propionate], 2-mercaptobenzimidazole, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, pentaerythrityl-tetrakis(3-laurylthiopropionate), and 2-mercaptobenzothiazole.

[0037] Singlet oxygen quenchers inactivate highly reactive singlet oxygen, which tends to oxidize and degrade dyes (fading), thereby preventing the oxidative degradation (fading) of dyes. Examples of singlet oxygen quenchers include transition metal complexes, dyes, amines, phenols, and sulfides. Particularly preferred materials are transition metal complexes of dialkyl phosphate, dialkyl dithiocarbamate, or benzenedithiol, with nickel, copper, or cobalt as the central metal. Examples include NKX1199, NKX113, and NKX114 manufactured by Hayashibara Biochemical Laboratories, Inc., and D1781, B1350, B4360, and T3204 manufactured by Tokyo Chemical Industry Co., Ltd.

[0038] Although each coloring material contained in the coloring layer 12 has excellent color correction function, it does not have sufficient resistance to light, particularly ultraviolet light, and therefore deteriorates over time when irradiated with ultraviolet light, and is no longer able to absorb light near the maximum absorption wavelength. In this embodiment, the optical film 10A has the transparent substrate 11 with an ultraviolet ray blocking rate of 85% or more disposed on the side where external light first enters than the colored layer 12, thereby suppressing the amount of ultraviolet rays contained in external light that enters the colored layer 12. This improves the light resistance of the colored layer 12 to ultraviolet rays. In the example shown in Figure 1, the transparent substrate 11 having ultraviolet absorbing function has the colored layer 12 formed directly on it, but it is sufficient that the transparent substrate 11 is positioned closer to the external light incident side than the colored layer 12, and another layer may be sandwiched between the transparent substrate 11 and the colored layer 12.

[0039] Furthermore, the present embodiment may include a hard coat layer 13 as a functional layer. The hard coat layer 13 is a layer portion that protects the transparent substrate 11 from external forces and has optical transparency. The transmittance of the hard coat layer 13 to visible light is preferably close to 100%. The surface hardness of the optical film 10A provided with the hard coat layer 13 is H or higher in pencil hardness at a load of 500 gf (4.9 N) (hereinafter referred to as 500 g load), and the pencil hardness is measured in accordance with JIS-K5600-5-4:1999.

[0040] The hard coat layer 13 is formed by applying a composition containing an active energy ray-curable resin, a photopolymerization initiator, and a solvent, drying it, and curing it by irradiating it with energy rays such as ultraviolet rays.

[0041] The active energy ray-curable resin is a resin that polymerizes and hardens when irradiated with active energy rays such as ultraviolet rays or electron beams, and can use, for example, a monofunctional, difunctional, or trifunctional or higher (meth)acrylate monomer. In this specification, "(meth)acrylate" is a general term for both acrylate and methacrylate, and "(meth)acryloyl" is a general term for both acryloyl and methacryloyl.

[0042] 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, and isobornyl (meth)acrylate. acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phosphate (meth)acrylate, ethylene oxide-modified phosphate (meth)acrylate, phenoxy (meth)acrylate, ethylene oxide-modified phenoxy (meth)acrylate, propylene oxide Oxide-modified phenoxy (meth)acrylate, nonylphenol (meth)acrylate, ethylene oxide-modified nonylphenol (meth)acrylate, propylene oxide-modified nonylphenol (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, ) acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hexahydrohydrogen phthalate, 2-(meth)acryloyloxypropyl tetrahydrohydrogen phthalate, dimethylaminoethyl (meth)acrylate, trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropropyl (meth)acrylate, 2-adamantane,Examples include adamantane derivative mono(meth)acrylates such as adamantyl acrylate having a monovalent mono(meth)acrylate derived from adamantanediol.

[0043] Examples of bifunctional (meth)acrylate compounds 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 glycol di(meth)acrylate.

[0044] Examples of trifunctional or higher (meth)acrylate compounds include tri(meth)acrylates such as trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris(2-hydroxyethylisocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, etc., trifunctional (meth)acrylate compounds such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tri(meth)acrylate. and polyfunctional (meth)acrylate compounds having three or more functional groups 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 ε-caprolactone.

[0045] Urethane (meth)acrylates can also be used as the active energy ray-curable resin. 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.

[0046] Examples of urethane (meth)acrylates 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, and dipentaerythritol pentaacrylate isophorone diisocyanate urethane prepolymer.

[0047] The active energy ray-curable resins described above may be used alone or in combination of two or more. In addition, the active energy ray-curable resins described above may be monomers in the composition for forming a hard coat layer, or may be partially polymerized oligomers.

[0048] The photopolymerization initiator may be any compound that generates radicals upon irradiation with ultraviolet light. Specific examples include acetophenone-based compounds, benzoin-based compounds, benzophenone-based compounds, oxime ester-based compounds, thioxanthone-based compounds, triazine-based compounds, phosphine-based compounds, quinone-based compounds, borate-based compounds, carbazole-based compounds, imidazole-based compounds, and titanocene-based compounds. Examples of suitable photopolymerization initiators include 2,2-ethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, dibenzoyl, benzoin, benzoin methyl ether, benzoin ethyl ether, p-chlorobenzophenone, p-methoxybenzophenone, Michler's ketone, acetophenone, 2-chlorothioxanthone, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide. These may be used alone or in combination.

[0049] Examples of the solvent include ethers such as dibutyl ether, dimethoxymethane, dimethoxyethane, diethoxyethane, propylene oxide, 1,4-dioxane, 1,3-dioxolane, 1,3,5-trioxane, tetrahydrofuran, anisole, and phenetole, ketones such as acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, and methylcyclohexanone, esters such as ethyl formate, propyl formate, n-pentyl formate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, n-pentyl acetate, and γ-butyrolactone, and cellosolves such as methyl cellosolve, cellosolve, butyl cellosolve, and cellosolve acetate. These may be used alone or in combination of two or more.

[0050] Furthermore, metal oxide fine particles may be contained in the composition for forming the hard coat layer 13 for the purpose of adjusting the refractive index or imparting hardness. Examples of metal oxide fine particles include zirconium oxide, titanium oxide, niobium oxide, antimony trioxide, antimony pentoxide, tin oxide, indium oxide, indium tin oxide, and zinc oxide.

[0051] The composition for forming the hard coat layer 13 may also contain any of silicon oxides, fluorine-containing silane compounds, fluoroalkyl silazanes, fluoroalkyl silanes, fluorine-containing silicon compounds, and perfluoropolyether group-containing silane coupling agents, which impart water repellency and / or oil repellency and enhance antifouling properties.

[0052] Other additives such as a leveling agent, an antifoaming agent, a photosensitizer, and a conductive material such as a quaternary ammonium cation or conductive metal particles may also be added to the composition for forming the hard coat layer 13. The conductive material imparts antistatic properties to the optical film.

[0053] Furthermore, a low refractive index layer 14A may be provided as a functional layer in this embodiment. When the optical film 10A is applied to a display device 50A, the low refractive index layer 14A is disposed on the side closest to a user (viewer) who views the display. In this embodiment, the low refractive index layer 14A is laminated on the surface of the hard coat layer 13 opposite to the transparent substrate 11. The thickness of the low refractive index layer 14A is not particularly limited, but is preferably 40 nm to 1 μm. The low refractive index layer 14A is made of a material having a refractive index lower than that of the hard coat layer 13. This causes interference between external light incident from the outside and reflected at the interface with the hard coat layer 13 and light reflected at the surface of the low refractive index layer 14A, thereby reducing the surface reflectance of the external light. Providing the low refractive index layer 14A can suppress surface reflection of external light, thereby improving the visibility of the display device 50A. The low refractive index layer 14A is a layer made of an inorganic substance or an inorganic compound. Examples of inorganic substances or inorganic compounds include fine particles such as LiF, MgF, 3NaF·AlF, AlF, and Na3AlF6, as well as silica fine particles. The use of porous silica fine particles or hollow silica fine particles, which have voids inside the particles, is effective in achieving a low refractive index. The composition for forming the low refractive index layer 14A may contain, in addition to the inorganic substance or inorganic compound, an active energy ray-curable resin, a photopolymerization initiator, a solvent, and other additives, as described for the hard coat layer 13.

[0054] The composition for forming the low refractive index layer 14A may contain any of silicon oxide, fluorine-containing silane compound, fluoroalkylsilazane, fluoroalkylsilane, fluorine-containing silicon compound, and perfluoropolyether group-containing silane coupling agent. By containing these materials, water repellency and / or oil repellency can be imparted to the low refractive index layer 14, thereby improving the antifouling properties.

[0055] The colored layer 12 is a layer portion of one or more layers formed on the 11b side of the transparent substrate 11, and the composition for forming the colored layer 12 contains an active energy ray-curable resin, a photopolymerization initiator, a dye, an additive, and a solvent. The active energy ray-curable resin, the photopolymerization initiator, and the solvent can be the same as those described for the hard coat layer 13. The dye contains the first coloring material, at least one of the second coloring materials, and the third coloring material, and the additive contains at least one of a radical scavenger, a peroxide decomposer, and a singlet oxygen quencher.

[0056] The optical film 10A can be produced by forming a colored layer 12 on the second surface 11b of the transparent substrate 11, and then forming a hard coat layer 13 and a low refractive index layer 14A on the first surface 11a of the transparent substrate 11 in this order. However, the order of the colored layer 12, the hard coat layer 13, and the low refractive index layer 14A is not particularly limited. For example, the colored layer 12 may be formed first, followed by the hard coat layer 13 and the low refractive index layer 14A, or the reverse order may be used. The colored layer 12, the hard coat layer 13, and the low refractive index layer 14A can be formed by applying a coating liquid containing the constituent materials of each layer, drying it, and curing it by irradiating it with active energy rays such as ultraviolet light. The low refractive index layer 14A can also be formed by other methods, such as vapor deposition or sputtering.

[0057] Furthermore, the optical film 10A of this embodiment may have other functional layers provided on the first surface 11a side of the transparent substrate 11 of the optical film as long as the necessary front luminance, external light reflection visibility, and color purity of the display light are obtained.

[0058] The display device 50A can be manufactured by preparing the display section 20, and then bonding and fixing the colored layer 12 of the optical film 10A to the surface of the color filter section 23 via an adhesive layer or the like.

[0059] In the display device 50A of this embodiment, when the light-emitting element 22 is turned on in response to an image signal, the display light generated by the light-emitting element 22 passes through the color filter section 23. As a result, light from the first light-emitting element 22R passes as red light, light from the second light-emitting element 22G passes as green light, and light from the third light-emitting element 22B passes as blue light through the colored layer 12, transparent substrate 11, hard coat layer 13, and low-refractive index layer 14A, and is emitted to the outside of the optical film 10A. Since the colored layer 12 has wavelength bands with good transmittance for the red, green, and blue wavelengths of the display light, it is possible to suppress a decrease in luminance of the display light of each color and improve the color purity of the display light of each color. Furthermore, since the transparent substrate 11 mainly absorbs light in the ultraviolet region, the display light is transmitted with almost no decrease in luminance. Since the low-refractive index layer 14A has good transmittance for visible light, the display light is emitted to the outside with almost no decrease in luminance.

[0060] On the other hand, external light enters the display device 50A through the optical film 10A. The low refractive index layer 14A reduces the surface reflectance of external light, thereby preventing a decrease in visibility due to excessive surface reflection of external light. External light incident on the transparent substrate 11 is incident on the colored layer 12 in a state in which wavelength components in the ultraviolet region are absorbed by the transparent substrate 11 . The colored layer 12 further absorbs wavelength components of the external light near the absorption wavelengths of the color materials contained in the colored layer 12. The external light then passes through the color filter section 23 and reaches the substrate 21. The substrate 21 includes metal parts with high reflectivity, such as wiring and electrodes. Therefore, the external light is reflected by the wiring and electrodes, and passes sequentially through the color filter section 23, the colored layer 12, the transparent substrate 11, the hard coat layer 13, and the low refractive index layer 14A before being emitted to the outside. An observer of the display device 50A sees not only the display light but also reflected light that is a combination of surface reflected light from external light of the display device 50A and internally reflected light that is external light that passes through and is reflected inside the display device 50A.

[0061] In this embodiment, external light passes through the colored layer 12 twice and is emitted to the outside, thereby reducing wavelength components different from the wavelength components of the display light, thereby reducing internal reflection of the external light and suppressing a decrease in brightness of the display light, thereby improving the color purity of the display light. Even when the display device 50A is in a non-display state, the chromaticness index a * , b * By setting the value to be between -5 and +5, the influence of the color tint of the optical film is reduced and the black tint of the display screen is maintained. In this embodiment, the transparent substrate 11 absorbs the ultraviolet light component of external light, preventing the coloring material in the coloring layer 12 from being deteriorated by exposure to ultraviolet light. Therefore, the spectral characteristics of the coloring material in the coloring layer 12 are likely to be maintained over time.

[0062] [Second embodiment] An optical film and a display device according to a second embodiment of the present invention will now be described. FIG. 4 is a schematic cross-sectional view showing an example of an optical film and a display device according to a second embodiment of the present invention. A display device 50C of this embodiment, the cross section of which in the thickness direction is shown in FIG. 4, includes an optical film 10C of this embodiment instead of the optical film 10A of the display device 50A of the first embodiment. The optical film 10C has the same structure as the optical film 10A, except that an oxygen barrier layer 16 is provided between the colored layer 12 and the hard coat layer 13. The following description will focus on the differences from the first embodiment.

[0063] The oxygen barrier layer 16 is a transparent layer that is light-transmitting. The oxygen permeability of the oxygen barrier layer 16 is 10 cc / m 2The oxygen barrier layer 16 preferably contains, as its main constituent material, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), vinylidene chloride, siloxane resin, or the like, and examples of materials that can be used include Maxive (registered trademark) manufactured by Mitsubishi Gas Chemical Company, Inc., EVAL (registered trademark) and Poval manufactured by Kuraray Co., Ltd., and Saran Latex (registered trademark) and Saran (registered trademark) resin manufactured by Asahi Kasei Corporation. Furthermore, inorganic particles such as silica particles, alumina particles, silver particles, copper particles, titanium particles, zirconia particles, and tin particles may be dispersed in the oxygen barrier layer 16 to reduce oxygen permeability.

[0064] When the optical film 10C is attached to a display device 50C, oxygen contained in the outside air does not reach the colored layer 12 unless it passes through the oxygen barrier layer 16. This suppresses deterioration of the color materials in the colored layer 12 due to light and heat caused by oxygen in the outside air. As a result, the light absorption performance of the colored layer 12 is maintained for a long period of time.

[0065] The oxygen barrier layer 16 of this embodiment can be disposed in any suitable location where it is desired to prevent oxygen from entering. For example, when it is desired to prevent oxygen from entering the colored layer 12 from the outside of the display device 50B, the oxygen barrier layer 16 can be disposed between suitable members or layers on the outer side of the colored layer 12. For example, if it is desired to prevent oxygen from entering the colored layer 12 from the display section 20 of the display device 50B, the oxygen barrier layer 16 can also be disposed between the color filter section 23 and the colored layer 12.

[0066] The optical film 10C and display device 50C of this embodiment have the same colored layer 12, hard coat layer 13, and low refractive index layer 14A as those of the first embodiment, and therefore have the same effects as those of the first embodiment. In particular, the optical film 10C of this embodiment further includes the oxygen barrier layer 16, and therefore, the dye in the colored layer 12 can be prevented from being oxidized and deteriorated by light and heat due to the influence of oxygen.

[0067] [Third embodiment] An optical film and a display device according to a third embodiment of the present invention will now be described. FIG. 5 is a schematic cross-sectional view showing an example of an optical film and a display device according to a third embodiment of the present invention. A display device 50D of this embodiment, the cross section of which in the thickness direction is shown in FIG. 5, includes an optical film 10D of this embodiment instead of the optical film 10A of the display device 50A of the first embodiment. The optical film 10D has the same structure as the optical film 10A, except that it includes an antiglare layer 17 instead of the low refractive index layer 14A and the hard coat layer 13. The following description will focus on the differences from the first embodiment.

[0068] The antiglare layer 17 is a layer portion having an antiglare function. The anti-glare function is a function that reduces the glare of external light by having minute irregularities on the surface and scattering the external light with these irregularities. The pencil hardness of the surface of the optical film 10D having the antiglare layer 17 is H or more, similar to the first embodiment.

[0069] The antiglare layer 17 can be formed by curing a coating liquid containing the same composition as the hard coat layer 13, plus organic and / or inorganic particles that provide antiglare functionality. The organic particles form fine irregularities on the surface of the antiglare layer 17, imparting the ability to diffuse external light. Examples of suitable organic particles include resin particles made of a translucent resin material such as acrylic resin, polystyrene resin, styrene-(meth)acrylic acid ester copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride, and polyethylene fluoride resin. To adjust the refractive index and dispersibility of the resin particles, two or more types of resin particles with different materials (refractive indexes) may be mixed. The inorganic particles adjust the sedimentation and aggregation of the organic particles in the antiglare layer 17. Examples of suitable inorganic particles include silica particles, metal oxide particles, and various mineral particles. Examples of suitable silica particles include colloidal silica and silica particles surface-modified with reactive functional groups such as (meth)acryloyl groups. Examples of metal oxide microparticles that can be used include alumina, zinc oxide, tin oxide, antimony oxide, indium oxide, titania, and zirconia. Examples of mineral microparticles that can be used include mica, synthetic mica, vermiculite, montmorillonite, iron-montmorillonite, bentonite, beidellite, saponite, hectorite, stevensite, nontronite, magadiite, ailalite, kanemite, layered titanic acid, smectite, and synthetic smectite. The mineral microparticles may be natural or synthetic (including substituted or derivative) materials, or mixtures of both. Among mineral microparticles, layered organic clays are more preferred. Layered organic clays refer to swelling clays in which organic onium ions are introduced between the layers. The organic onium ions are not limited as long as they can be organized by utilizing the cation exchange properties of the swelling clay. When layered organic clay minerals are used as mineral microparticles, the aforementioned synthetic smectites can be preferably used. The synthetic smectite has the function of increasing the viscosity of the coating liquid 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.

[0070] The composition for forming the antiglare layer 17 may contain any of silicon oxide, a fluorine-containing silane compound, a fluoroalkylsilazane, a fluoroalkylsilane, a fluorine-containing silicon-based compound, and a perfluoropolyether group-containing silane coupling agent. These materials impart water-repellent and / or oil-repellent properties to the antiglare layer 17 and can improve the stain resistance of the optical film 10D.

[0071] The antiglare layer 17 may be formed as a layer in which, from the first surface 11a side, a layer with a relatively high refractive index and a layer with a relatively low refractive index are laminated. The antiglare layer 17 with unevenly distributed materials can be formed, for example, by applying a composition containing a low refractive index material containing surface-modified silica microparticles or hollow silica microparticles and a high refractive index material, and then phase-separating the material by utilizing the difference in surface free energy between the two layers. When the antiglare layer 17 is formed of two phase-separated layers, it is preferable that the layer with the relatively high refractive index on the transparent substrate 11a side has a refractive index of 1.50 to 2.40, and the layer with the relatively low refractive index on the front surface of the optical film 10D has a refractive index of 1.20 to 1.55.

[0072] The optical film 10D and display device 50D of this embodiment include the same colored layer 12 and transparent substrate 11 as those of the first embodiment, and therefore have the same functions as those of the first embodiment. In particular, the optical film 10D of this embodiment includes the antiglare layer 17, and therefore external light is scattered by the antiglare layer 17. This suppresses surface reflection and glare of external light, improving the visibility of the display screen and display light and suppressing degradation of display quality due to external light reflection.

[0073] [Fourth embodiment] An optical film and a display device according to a fourth embodiment of the present invention will now be described. FIG. 6 is a schematic cross-sectional view showing an example of an optical film and a display device according to a fourth embodiment of the present invention. A display device 50E of this embodiment, the cross section of which in the thickness direction is shown in FIG. 6, includes the optical film 10E of this embodiment instead of the optical film 10D of the display device 50D of the third embodiment. The optical film 10E has the same structure as the optical film 10D, except that a low refractive index layer 14E is laminated on the antiglare layer 17. The following description will focus on the differences from the third embodiment.

[0074] The low refractive index layer 14E is similar to the low refractive index layer 14A in the first embodiment, except that it has a refractive index lower than that of the antiglare layer 17. This causes interference between the reflected light of external light incident from the interface with the antiglare layer 17 and the reflected light from the surface of the low refractive index layer 14E, thereby reducing the reflectance of external light. By providing the low refractive index layer 14E, reflection of external light can be suppressed, and therefore visibility of the display device 50E is improved.

[0075] The optical film 10E and the display device 50E of this embodiment include the same colored layer 12 and antiglare layer 17 as those of the third embodiment, and therefore have the same functions as those of the third embodiment. In particular, the optical film 10E of this embodiment has a low refractive index layer 14E on the outer side, which suppresses surface reflection and glare of external light, thereby improving the visibility of the display screen and display light and suppressing degradation of display quality due to external light reflection.

[0076] In the above embodiments and modifications, the light-emitting elements are described as organic EL elements. However, the type of light-emitting element is not limited to organic EL elements. For example, examples of light-emitting elements include white LED elements, inorganic phosphor light-emitting elements, and quantum dot light-emitting elements. When the light source emits monochromatic light of the three primary colors RGB, the display unit 20 can be configured without the color filter unit 23.

[0077] In the above-described embodiments and modified examples, the optical film has been described as having various functional layer configurations other than the colored layer, such as a low refractive index layer, a hard coat layer, an oxygen barrier layer, and an antiglare layer, but the configuration of the functional layers of the optical film is not limited to these. For example, the optical film may have a water-repellent antifouling layer or an antistatic layer containing a conductive material. The functional layer may be a layer portion having two or more functions of each functional layer.

[0078] In the above-described embodiments and modifications, examples have been described in which at least the transparent substrate has ultraviolet absorption properties. However, the optical film may further include an ultraviolet absorbing layer having an ultraviolet absorbing function. In the optical film, the colored layer or a functional layer other than the colored layer may also function as the ultraviolet absorbing layer. For example, the ultraviolet absorbing layer may be disposed outside a layer portion that is desired to be protected from ultraviolet radiation, in which case the inner layer portion can be protected from ultraviolet radiation irradiated from outside the optical film. [Example]

[0079] The optical film according to the present invention will be further explained using Examples 1 to 12 and Comparative Examples 1 to 6. The present invention is not limited in any way by the specific content of each of the following Examples.

[0080] In the following Examples and Comparative Examples, optical films 1 to 18 were prepared having the layer structures shown in Tables 1 and 2 below, and the properties of the prepared optical films 1 to 15 were evaluated. In addition, the display device properties of organic EL panels were confirmed by simulation using optical films 7, 12, and 16 to 18.

[0081] [Table 1]

[0082] [Table 2]

[0083] <Production of optical film> The method for forming each layer will be described below.

[0084] [Formation of colored layer] (Materials used in the composition for forming the colored layer) The following materials were used as the color layer forming composition used to form the color layer. The maximum absorption wavelength and half-width of the colorant were calculated from the characteristic values ​​of the cured coating film using spectral transmittance. Dye-1: Pyrromethene cobalt complex dye represented by the following chemical formula 1 (maximum absorption wavelength: 493 nm, half-width: 26 nm)

[0085] (chemical formula 1) [ka]

[0086] Second colorant: Dye-2: Tetraazaporphyrin copper complex dye (FDG-007, manufactured by Yamada Chemical Co., Ltd., maximum absorption wavelength 595 nm, half-width 22 nm) Dye-3: Tetraazaporphyrin copper complex dye (Yamamoto Chemicals Co., Ltd. PD-311S, maximum absorption wavelength 586 nm, half-width 22 nm) Third colorant: Dye-4: Phthalocyanine copper complex dye (Yamada Chemical Co., Ltd. FDN-002, maximum absorption wavelength 800 nm, minimum transmittance wavelength 780 nm in the 400-780 nm range) Dye-5 Phthalocyanine Cobalt Complex Dye (Yamada Chemical FDR-002, maximum absorption wavelength 683 nm, minimum transmittance wavelength 683 nm in the 400-780 nm range) Additives: Hindered amine light stabilizer Chimassorb® 944FDL (BASF Japan, molecular weight 2000-3100) Hindered amine light stabilizer Tinuvin® 249 (BASF Japan, molecular weight 482) Singlet oxygen quencher D1781 (Tokyo Chemical Industry Co., Ltd.) UV absorber: Tinuvin® 479 (manufactured by BASF Japan, maximum absorption wavelength: 322 nm) LA-36 (ADEKA, maximum absorption wavelengths: 310 nm, 350 nm) Active energy ray curing resin: UA-306H (Kyoeisha Chemical Co., Ltd., pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer) DPHA (Dipentaerythritol hexaacrylate) PETA (Pentaerythritol Triacrylate) Initiator: Omnirad (registered trademark) TPO (manufactured by IGM Resing BV, absorption wavelength peaks 275 nm, 379 nm) ·solvent: MEK (methyl ethyl ketone) Methyl acetate

[0087] (Transparent base material) The following transparent substrates were used: TAC: Triacetylcellulose film (Fujifilm TG60UL, substrate thickness 60 μm, UV blocking rate 92.9%) PMMA: Polymethyl methacrylate film (Sumitomo Chemical W001U80, substrate thickness 80 μm, UV blocking rate 93.4%) PET1: Polyethylene terephthalate film (Toyobo SRF, substrate thickness 80 μm, UV blocking rate 88.3%) PET2: Polyethylene terephthalate film (SKC TOR20, substrate thickness 40 μm, UV blocking rate 88.6%)

[0088] (Colored layer formation) The colored layer-forming composition shown in Table 3 was applied to one side of the transparent substrate shown in [Table 1] and [Table 2], and dried in an oven at 80°C for 60 seconds. Thereafter, an ultraviolet irradiation device was used to apply the composition to the substrate at an irradiation dose of 150 mJ / cm. 2 The coating film was cured by irradiating it with ultraviolet light (H bulb light source, manufactured by Fusion UV Systems Japan Co., Ltd.), and colored layers 1 to 8 were formed so that the film thickness after curing was 5.0 μm. The amounts added are by mass.

[0089] [Table 3]

[0090] [Formation of functional layer] Oxygen barrier layer 1-forming composition: PVA117 (Kuraray Co., Ltd.) 80% aqueous solution

[0091] (Oxygen barrier layer formation) The composition for forming the oxygen barrier layer 1 was applied to the structure of Example 11 shown in Table 1, and dried to obtain an oxygen permeability of 1 cc / m 2 An oxygen barrier layer 1 having a temperature of 1000 KPa (day) atm was formed.

[0092] (Materials used in the composition for forming the hard coat layer) The following materials were used as the hard coat layer forming composition used to form the hard coat layer. UV absorber: Tinuvin® 479 (manufactured by BASF Japan, maximum absorption wavelength: 322 nm) LA-36 (ADEKA, maximum absorption wavelengths: 310 nm, 350 nm) Active energy ray curing resin: UA-306H (Kyoeisha Chemical Co., Ltd., pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer) DPHA (Dipentaerythritol hexaacrylate) PETA (Pentaerythritol Triacrylate) Initiator: Omnirad (registered trademark) TPO (manufactured by IGM Resins BV, absorption wavelength peaks 275 nm and 379 nm) Omnirad (registered trademark) 184 (manufactured by IGM Resins BV, absorption wavelength peaks 243 nm and 331 nm) ·solvent: MEK (methyl ethyl ketone) Methyl acetate

[0093] (Hard coat layer formation) A composition for forming a hard coat layer shown in [Table 4] below was applied onto the transparent substrate, colored layer, or oxygen barrier layer shown in [Table 1] and [Table 2], dried in an oven at 80°C for 60 seconds, and then exposed to a radiation dose of 150 mJ / cm using an ultraviolet irradiation device. 2 The coating film was cured by irradiating it with ultraviolet light (H bulb, light source, manufactured by Fusion UV Systems Japan) at 1000 K. The hard coat layers 1 and 2 shown in Table 1 and Table 2 had a film thickness of 5.0 μm after curing.

[0094] [Table 4]

[0095] (Composition for forming anti-glare layer 1) The following composition was used for forming the antiglare layer 1. Active energy ray curing resin: Light acrylate PE-3A (manufactured by Kyoeisha Chemical Co., Ltd., refractive index 1.52) 43.7 parts by mass Photoinitiator: Omnirad (registered trademark) TPO (manufactured by IGM Resins BV, absorption wavelength peaks 275 nm, 379 nm) 4.55 parts by mass Resin particles: Styrene-methyl methacrylate copolymer particles (refractive index 1.515, average particle size 2.0 μm) 0.5 parts by mass ·Inorganic fine particles 1: Synthetic smectite 0.25 parts by mass ·Inorganic fine particles 2: Alumina nanoparticles, average particle size 40nm, 1.0 parts by mass ·solvent Toluene 15 parts by mass Isopropyl alcohol 35 parts by mass

[0096] (Formation of antiglare layer) The composition for forming antiglare layer 1 was applied to the transparent substrate shown in [Table 1], dried in an oven at 80°C for 60 seconds, and then irradiated with a UV irradiator at a dose of 150 mJ / cm. 2The coating was cured by irradiating it with ultraviolet light (H bulb light source, manufactured by Fusion UV Systems Japan) at 1000 kJ / min, to form an antiglare layer 1 having a thickness of 5.0 μm after curing, as described in [Table 1].

[0097] (Composition for forming low refractive index layer 1) The following composition was used for forming the low refractive index layer 1. Refractive index adjuster: Porous silica microparticle dispersion (average particle size 75 nm, solid content 20%, solvent methyl isobutyl ketone) 8.5 parts by mass Antifouling agent: Optool AR-110 (manufactured by Daikin Industries, Ltd., solid content 15%, solvent methyl isobutyl ketone) 5.6 parts by mass Active energy ray curing resin: Pentaerythritol triacrylate 0.4 parts by mass Initiator: Omnirad (registered trademark) 184 (manufactured by IGM Resins BV) 0.07 parts by mass Leveling agent: RS-77 (manufactured by DIC) 1.7 parts by mass ·solvent: Methyl isobutyl ketone 83.73 parts by mass

[0098] (Formation of low refractive index layer 1) The composition for forming low refractive index layer 1 having the above composition was applied onto the hard coat layer and the antiglare layer shown in [Table 1] and [Table 2], and dried in an oven at 80°C for 60 seconds. Thereafter, an ultraviolet irradiation device (manufactured by Fusion UV Systems Japan, light source H bulb) was used to irradiate the layer with an irradiation dose of 200 mJ / cm. 2 The coating was cured by irradiating it with ultraviolet light at 1000 nm to form a low refractive index layer 1 shown in Tables 1 and 2, having a thickness of 100 nm after curing.

[0099] [Film characteristic evaluation] The obtained optical films 1 to 15 were evaluated as follows.

[0100] (UV shielding rate) In Examples 1 to 12, in which a transparent substrate was used above the colored layer, the transmittance of the substrate was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.). For Comparative Examples 1 to 3, in which the colored layer was used above the substrate, the layer above the colored layer was peeled off using cellophane tape conforming to the JIS-K5600 adhesion test, and the transmittance of the upper layer of the colored layer was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.) with the adhesive tape as a reference. Using these transmittances, the average transmittance [%] in the ultraviolet range (290 nm to 400 nm) was calculated, and the ultraviolet shielding rate [%] was calculated by subtracting the average transmittance [%] in the ultraviolet range (290 nm to 400 nm) from 100%.

[0101] (Pencil hardness test) A scratch hardness test was performed on the surface of the optical film using a Clemens-type scratch hardness tester (HA-301, manufactured by Tester Sangyo Co., Ltd.) in accordance with JIS-K5600-5-4:1999, using a pencil (UNI, manufactured by Mitsubishi Pencil Co., Ltd., pencil hardness H) with a load of 500 gf (4.9 N) (hereinafter referred to as 500 g load). The change in appearance due to scratches was evaluated visually, with cases where no scratches were observed being rated as good (represented as "◯" in Tables 5 and 6 below), and cases where scratches were observed being poor (represented as "×" in Table 6 below).

[0102] (Lightfastness test) The reliability of the obtained optical film including the colored layer was tested using a xenon weather meter tester (X75, manufactured by Suga Test Instruments Co., Ltd.) under conditions of xenon lamp illuminance of 60 W / cm. 2The test was conducted for 120 hours at a tester temperature of 45°C and humidity of 50% (300-400 nm). Transmittance measurements were performed using an automatic spectrophotometer (Hitachi, Ltd., U-4100) before and after the test. The transmittance difference before and after the test was calculated as follows: ΔTλ1 at wavelength λ1, which represents the minimum transmittance before the test, in the wavelength range of 470-530 nm; ΔTλ2 at wavelength λ2, which represents the minimum transmittance before the test, in the wavelength range of 560-620 nm; and ΔTλ3 at wavelength λ2, which represents the minimum transmittance before the test, in the wavelength range of 650-780 nm. The closer the transmittance difference to zero, the better. A transmittance difference of |ΔTλN|≦20 (N=1-3) is preferred, and a value of |ΔTλN|≦10 (N=1-3) is even more preferred.

[0103] The results of the evaluation of the above items are shown in Tables 5 and 6 below.

[0104] [Table 5]

[0105] [Table 6]

[0106] As shown in Tables 5 and 6, by providing a transparent substrate with a UV blocking rate of 85% or more in the upper layer, the hardness of the optical film was maintained and the light resistance of the colored layers containing the first to third color materials was significantly improved. Providing UV absorption capability in the colored layer was less effective, so it was preferable to provide it as a separate layer on top. Furthermore, the light resistance of the colored layer was further improved by laminating an oxygen-blocking layer and by incorporating a high-molecular-weight hindered amine light stabilizer as a radical scavenger and a dialkyldithiocarbamate nickel complex as a singlet oxygen quencher in the colored layer.

[0107] [Display device characteristic evaluation] The obtained optical films 7, 12, and 16 to 18 were evaluated as follows.

[0108] (White display transmission characteristics) The transmittance of the obtained optical film was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the efficiency of light transmitted through the optical film during white display was calculated using this transmittance, which was evaluated as the white display transmittance characteristic. The efficiency was calculated as the ratio of the light intensity value at each wavelength of light transmitted through the optical film to the light intensity value at each wavelength during white display emitted from a white organic EL light source (hereinafter sometimes referred to as an organic EL light source) and output through a color filter, which is set to 100. The higher the light intensity ratio, the higher the luminance efficiency of the light source. The spectrum of light emitted by the EL light source is shown in Figure 7.

[0109] (Display device reflection characteristics 1) The transmittance T(λ) and surface reflectance R2(λ) of the obtained optical film were measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.). To measure the surface reflectance R2(λ), a matte black paint was applied to the surface of the triacetyl cellulose film of the transparent substrate on which the colored layer and functional layer were not formed to provide anti-reflection, and the spectral reflectance was measured at an incident angle of 5°, and the surface reflectance R2(λ) was determined. The electrode reflectance R E The relative reflectance value, where (λ) is set to 100% for all wavelengths from 380 nm to 780 nm and the light intensity of the reflected light reflected by a D65 light source without an optical film in place is set to 100, was calculated based on the above formulas (4), (5), (7), and (9) without considering the interface reflection and surface reflection at each layer, and was evaluated as the display device reflection characteristic 1. The lower the relative reflectance value, the lower the intensity of the reflected light, and the higher the display quality.

[0110] (Display device reflection hue 1) The transmittance T(λ) and surface reflectance R2(λ) of the obtained optical film were measured using an automatic spectrophotometer (model number: U-4100, manufactured by Hitachi, Ltd.). To measure the surface reflectance R2(λ), a matte black paint was applied to the surface of the triacetyl cellulose film of the transparent substrate on which the colored layer and functional layer were not formed to provide anti-reflection, and the spectral reflectance was measured at an incident angle of 5°, and the surface reflectance R2(λ) was determined. The electrode reflectance R E(λ) is set to 100% for wavelengths from 380 nm to 780 nm, and the chromaticity index (value) of the reflected hue for the D65 light source is a * and b * was calculated based on the above formulas (1) to (9) without taking into consideration the interface reflection and surface reflection in each layer, and evaluated as the reflection hue 1 of the display device. a * Oyob * The closer to zero the value, the less coloring there is and the better, and it is preferable that the value is between -5 and +5.

[0111] (Display device reflection characteristics 2) Electrode reflectance R E The results calculated in the same manner as for display device reflection characteristic 1 were evaluated as display device reflection characteristic 2, except that (λ) was the electrode reflectance obtained from the reflectance measurement of the organic light-emitting display device (OLED55C8PJA, organic EL television manufactured by LG Electronics) shown in Figure 9. As with display device reflection characteristic 1, the lower the relative reflectance value, the lower the intensity of reflected light and the higher the display quality.

[0112] (Display device reflection hue 2) Electrode reflectance R E The results calculated in the same manner as for display device reflective hue 1 were evaluated as display device reflective hue 2, except that (λ) was the electrode reflectance obtained from the reflectance measurement of the organic light-emitting display device (organic EL television, OLED55C8PJA, manufactured by LG Electronics) shown in Figure 9. * Oyob * The closer to zero the value, the less coloring there is and the better, and it is preferable that the value is between -5 and +5.

[0113] (color reproducibility) The transmittance of the obtained optical film was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the NTSC ratio was calculated from the CIE1931 chromaticity value calculated using this transmittance and the red, green, and blue display spectra shown in Figure 8 output through the organic EL light source and color filter with the spectrum shown in Figure 7, and was used to evaluate color reproducibility. A higher NTSC ratio is preferable as it provides a wider range of color reproducibility.

[0114] The results of the evaluation of the above items are shown in Table 7 below.

[0115] [Table 7]

[0116] As shown in Table 7, the display device with the colored layer had significantly lower reflectivity. It is said that the transmittance is halved with a circular polarizer, but the display device with the colored layer had excellent luminance efficiency and improved color reproducibility, as shown by the evaluation value of the white display transmittance. Furthermore, the colored layer with the first, second, and third color materials shown in this example had a significantly lower electrode reflectivity R E Chromaticness index a of the reflection hue when (λ) is 100% for all wavelengths from 380 nm to 780 nm * and b * It was possible to adjust the absorption intensity of the colorant so that each of the above values ​​was within the range of -5 or more and +5 or less. In other words, it was possible to bring the reflective hue closer to neutral. Furthermore, this characteristic was shown to be able to maintain a neutral reflective hue even in a display device reflective hue 2, which was changed to the electrode reflectance of an actual organic light-emitting display device, confirming that the display quality of the display device was improved. As described above, one aspect of the present invention is to neutralize the reflective hue of an optical film having a colored layer by adjusting the compounding ratio of the first, second, and third colorants for the electrode reflectance of organic light-emitting display devices having various wavelength dispersions.

[0117] Although the preferred embodiments and modifications of the present invention have been described above with reference to examples, the present invention is not limited to these embodiments and examples. Addition, omission, substitution, and other modifications of the configuration are possible within the scope of the present invention. Furthermore, the present invention is not limited by the foregoing description, but is limited only by the appended claims. [Explanation of symbols]

[0118] 10A, 10B, 10C, 10D, 10E Optical Film 11 Transparent base material 11a 1st page 11b Side 2 12 Colored layer 14A, 14B, 14E Low refractive index layer 16 Oxygen barrier layer 17 Anti-glare layer 20 Display section 21 PCB 22 Light-emitting element 22R First light-emitting element 22G Second light-emitting element 22B third light-emitting element 23 Color filter section 50A, 50B, 50C, 50D, 50E display unit

Claims

1. A colored layer-forming composition containing an active energy ray-curable resin, a photopolymerization initiator, a dye, and a solvent, The dye is a first coloring material having a maximum absorption wavelength in the range of 470 nm to 530 nm and an absorption spectrum half width of 15 nm to 45 nm; a second coloring material having a maximum absorption wavelength in the range of 560 nm to 620 nm and an absorption spectrum half width of 15 nm to 55 nm; a third coloring material having the lowest transmittance in the wavelength range of 400 to 780 nm, the third coloring material having the lowest transmittance in the wavelength range of 650 nm or more and 780 nm or less; In a layer having a thickness of 5 μm formed using the color layer-forming composition, the hue value a defined by the following formulas (1) to (9) is ＊ and b ＊ are in the range of -5 to +5, respectively. Composition for forming a colored layer. [Equation 1] [Equation 2] [Equation 3] [Equation 4] [Equation 5] [Equation 6] [Equation 7] [Equation 8] [Equation 9] where λ is a variable representing wavelength, and t is X ｎ , Y ｎ , Z ｎ are variables that represent the ratios of X, Y, and Z to a calculated from equations (1) to (3) ＊ , b ＊ is CIE 1976L ＊ a ＊ b ＊ It is calculated in accordance with the calculation method in the color space (CIELAB color space). ｎ , Y ｎ , Z ｎ are the tristimulus values ​​at the white point of the D65 illuminant. In formula (4), R Ｅ (λ) is a function representing the reflectance [%] on a perfectly diffuse reflecting surface (each wavelength 100%), R2(λ) is a function representing the surface reflectance [%] on the outermost surface of the functional layer, and T(λ) is a function representing the transmittance [%] of the optical film. In formulas (6) to (9), P Ｄ６５ (λ) is the D65 light source spectrum, and overline x(λ), overline y(λ), and overline z(λ) are color-matching functions in a CIE 1931 2° observer. The definite integrals in the formulas (6) to (9) can be obtained by appropriate numerical integration. When performing the numerical integration, the wavelength interval is set to 1 nm.

2. The first colorant is a pyrromethene cobalt complex, the second coloring material is a tetraazaporphyrin copper complex, the third coloring material is a phthalocyanine copper complex, A layer having a thickness of 5 μm is formed using the color layer-forming composition on a transparent substrate having an ultraviolet shielding rate of 85% or more in accordance with JIS L 1925, and the layer is then exposed to a xenon lamp illuminance of 60 W / cm under conditions of a temperature of 45° C. and a humidity of 50% RH. ２ before and after a light resistance test in which light of a wavelength of 300 to 400 nm is irradiated from the transparent substrate side for 120 hours, the transmittance difference ΔTλ1 before and after the test at a wavelength λ1 that shows the minimum transmittance before the test in a wavelength range of 470 nm to 530 nm, the transmittance difference ΔTλ2 before and after the test at a wavelength λ2 that shows the minimum transmittance before the test in a wavelength range of 560 nm to 620 nm, and the transmittance difference ΔTλ3 before and after the test at a wavelength that shows the minimum transmittance before the test in a wavelength range of 650 nm to 780 nm are all 20 points or less. The colored layer forming composition according to claim 1 .

3. The ink contains at least one additive selected from the group consisting of a radical scavenger, a peroxide decomposer, and a singlet oxygen quencher. The colored layer forming composition according to claim 2 .

4. The radical scavenger contains a hindered amine-based light stabilizer having a molecular weight of 2000 or more. The colored layer forming composition according to claim 3 .

5. The singlet oxygen quencher contains any one of dialkyl phosphate, dialkyl dithiocarbamate, benzenedithiol, and a transition metal complex thereof. The colored layer forming composition according to claim 3 .

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