Circular polarizer

Abstract

The present invention provides a circular polarizer capable of improving the reflected color by using a retardation film having flat dispersion characteristics, and an OLED device including the circular polarizer. The present application relates to a circular polarizer, and can provide an OLED device including the circular polarizer, which can improve reflected color using a retardation film with flat dispersion characteristics.

Description

[Technical Field]

[0001] The present application relates to a circular polarizer.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2018-0133584, filed on November 2, 2018, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference. [Background technology]

[0003] A circular polarizer, which basically includes a polarizer and a retardation film, can be used to reduce surface reflection in the off state of an OLED panel. For example, Patent Document 1 (Japanese Patent Laid-Open No. 8-321381) discloses a method of arranging a circular polarizer on the transparent electrode side of an organic light-emitting device. When the retardation film used in the circular polarizer has reverse dispersion characteristics, it is the most excellent because it produces natural reflected color, but it is very expensive due to the characteristics of the material. Summary of the Invention [Problem to be solved by the invention]

[0004] The present application provides a circular polarizer capable of improving reflected color using a retardation film having flat dispersion characteristics, and an OLED device including the circular polarizer. [Means for solving the problem]

[0005] The present application relates to a circular polarizer. FIG. 1 exemplarily illustrates a circular polarizer of the present application. As shown in FIG. 1, a circular polarizer 100 of the present application may include an antireflection film 10, a polarizer 20, a retardation film 30, and an adhesive layer 40, in that order. The retardation film may have flat dispersion characteristics. The retardation film may have an optical axis that forms an angle of 37 degrees to 43 degrees with the absorption axis of the polarizer. The circular polarizer may have a transmittance of 30% or less at a wavelength of 430 nm.

[0006] The present invention provides a circular polarizer that can improve the reflected color even when a retardation film having flat dispersion characteristics is used. The circular polarizer of the present invention will now be described in detail.

[0007] The reflectance of the anti-reflection film may be adjusted within a range such that the reflectance measured when the circular polarizer is attached to an OLED panel described below is about 2.0% or less, 1.95% or less, 1.85% or less, 1.75% or less, 1.65% or less, or 1.50% or less. The reflectance may refer to the luminous reflectance Y(D65).

[0008] The reflectance of the anti-reflection film at a wavelength of 550 nm may be within a range of 0.1% to 1.2%, and specifically, the reflectance of the anti-reflection film at a wavelength of 550 nm may be 0.1% or more, 0.2% or more, 0.4% or more, or 0.6% or more, and may be 1.2% or less, 1.1% or less, 1.0% or less, or 0.9% or less.

[0009] The anti-reflection film may have a transmittance of 90% or more, or 95% or more, for light with a wavelength of 380 nm to 780 nm. The haze of the anti-reflection film may be, for example, 1% or less. The lower limit of the haze of the anti-reflection film is not particularly limited, but may be, for example, 0.01% or more.

[0010] Anti-reflection films have an L determined according to the method defined in CIE 1976. * a * b * Color coordinate standard a * >0, b * >0 and a * * Through the use of such an anti-reflection film, it may be further advantageous to improve the reflected color feeling by using a retardation film having flat dispersion characteristics.

[0011] ​The anti-reflection film may have a minimum reflection wavelength in the range of 400 nm to 530 nm. Herein, the minimum reflection wavelength may refer to the wavelength at which the reflectance appears lowest in the reflectance spectrum of the anti-reflection film relative to the wavelength. The minimum reflectance of the anti-reflection film may be, for example, 1.0% or less. Herein, the minimum reflectance may refer to the reflectance at which the reflectance appears lowest in the reflectance spectrum of the anti-reflection film relative to the wavelength.

[0012] The reflectance spectrum of an anti-reflection film may exhibit a U-shaped graph versus wavelength. FIG. 2(a) exemplarily illustrates a U-shaped graph, and FIG. 2(b) exemplarily illustrates a W-shaped graph. However, FIG. 2 is merely a diagram for exemplifying a U-shaped graph, and the scope of the present application is not limited to FIG. 2. The anti-reflection film may have a reflection band (region R1 in FIG. 2(a)) exhibiting the lowest reflectance within the wavelength range of 380 nm to 780 nm, for example, a wavelength band with a reflectance of 1% or less. This U-shaped graph can be conceptually distinguished from a W-shaped graph, which is a region (regions R1 and R2 in FIG. 2(b)) with two reflection bands exhibiting the lowest reflectance within the wavelength range of 380 nm to 780 nm. The use of such an anti-reflection film may further enhance the improvement of reflective color using a retardation film with flat dispersion characteristics.

[0013] As long as the optical properties of the anti-reflection film are within the above range, the material can be appropriately selected. For example, the anti-reflection film can include a low refractive index layer. It is known to adjust the optical properties of the anti-reflection film within the above range. For example, the minimum reflection wavelength of the anti-reflection film tends to shift to longer wavelengths as the thickness of the low refractive index layer increases, and tends to shift to shorter wavelengths as the thickness of the low refractive index layer decreases. For example, the minimum reflectance of the anti-reflection film tends to decrease as the refractive index of the low refractive index material decreases.

[0014] The low refractive index layer may include a low refractive index material. In one example, the low refractive index material may be low refractive index inorganic particles. The refractive index of the low refractive index inorganic particles at a wavelength of 550 nm may be, for example, 1.5 or less, 1.45 or less, or 1.40 or less. The lower limit of the refractive index may be, for example, 1.0 or more, 1.1 or more, 1.2 or more, or 1.3 or more.

[0015] In one example, the low refractive index inorganic particles may be silica-based particles. Examples of silica-based particles include hollow silica, mesoporous silica, etc. In another example, magnesium fluoride (MgF2) may be used as the low refractive index inorganic particles.

[0016] In one example, the low refractive index inorganic particles may be nano-sized particles. The average particle size of the low refractive index inorganic particles may be, for example, within a range of 10 nm to 700 nm, 10 nm to 500 nm, 10 nm to 300 nm, 10 nm to 200 nm, or 10 nm to 100 nm.

[0017] The thickness of the low refractive layer can be appropriately adjusted taking into account the objectives of the present application. The thickness of the low refractive layer can be, for example, within the range of 10 nm to 500 nm, 10 nm to 300 nm, 10 nm to 200 nm, 50 nm to 200 nm, or 100 nm to 200 nm. As described above, the minimum reflection wavelength of the anti-reflection film can be adjusted depending on the thickness of the low refractive layer, so the thickness of the low refractive layer can be appropriately adjusted within the above range taking into account the desired minimum reflection wavelength.

[0018] The low refractive layer may further contain a binder resin, and the low refractive inorganic particles may be present in a dispersed state within the binder resin.

[0019] The low refractive index layer may contain 30 to 600 parts by weight of low refractive index inorganic particles relative to 100 parts by weight of binder resin. Specifically, the low refractive index inorganic particles may be contained in a range of 30 to 500 parts by weight, 30 to 400 parts by weight, 30 to 300 parts by weight, 30 to 200 parts by weight, or 100 to 200 parts by weight relative to 100 parts by weight of binder resin. If the content of the low refractive index inorganic particles is too high, the reflectance may increase and excessive surface irregularities may occur, which may reduce surface properties such as scratch resistance and stain resistance.

[0020] The binder resin may be, for example, a photopolymerizable compound. Specifically, the photopolymerizable compound may include a monomer or oligomer containing a (meth)acrylate group or a vinyl group. More specifically, the photopolymerizable compound may include a monomer or oligomer containing one or more, two or more, or three or more (meth)acrylate groups or vinyl groups.

[0021] Specific examples of monomers or oligomers containing (meth)acrylate groups include pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tolylene diisocyanate, trimethylolpropane tri(meth)acrylate, trimethylolpropane polyethoxy tri(meth)acrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, butanediol dimethacrylate, butyl methacrylate, or a mixture of two or more thereof, or a urethane-modified acrylate oligomer, an epoxy acrylate oligomer, an ether acrylate oligomer, a dendritic acrylate oligomer, or a mixture of two or more thereof. In this case, the molecular weight of the oligomer is preferably within the range of 1,000 to 10,000.

[0022] Specific examples of the vinyl group-containing monomer or oligomer include divinylbenzene, styrene, and paramethylstyrene.

[0023] Meanwhile, the photopolymerizable compound may further include a fluorine-containing (meth)acrylate monomer or oligomer in addition to the above-mentioned monomer or oligomer. When the fluorine-containing (meth)acrylate monomer or oligomer is further included, the weight ratio of the fluorine-containing (meth)acrylate monomer or oligomer to the monomer or oligomer containing a (meth)acrylate group or a vinyl group may be within the range of 0.1% to 10%.

[0024] The anti-reflection film may further include a substrate layer, and the low refractive layer may be formed on one surface of the substrate layer.

[0025] The substrate layer may contain a light-transmitting resin. Therefore, the substrate layer may be a light-transmitting substrate layer. The substrate layer may have a transmittance of 90% or more for light with a wavelength of 380 nm to 780 nm, for example. The substrate layer may have a haze of 1% or less for light with a wavelength of 380 nm to 780 nm, for example. By using such a substrate layer, it may be more advantageous to provide an anti-reflection film that can maintain high transmittance while reducing reflectance.

[0026] The substrate layer may include at least one selected from the group consisting of triacetyl cellulose (TAC) film, cycloolefin polymer film, poly(meth)acrylate film, polycarbonate film, polynorbornene film, and polyester film. The thickness of the substrate layer may be in the range of 10 μm to 300 μm in consideration of productivity, but is not limited thereto.

[0027] The low refractive layer can be produced by coating and curing a composition for forming a low refractive layer on a substrate layer. The composition for forming a low refractive layer can include the low refractive inorganic particles and can further include the binder resin. As described below, when a hard coating layer is formed on a substrate layer, the low refractive layer can be formed by coating and curing the composition for forming a low refractive layer on the hard coating layer.

[0028] The method for coating the composition for forming the low refractive layer is not particularly limited, and can be performed by a known coating method such as spin coating, bar coating, roll coating, gravure coating, or blade coating.

[0029] The method for curing the composition for forming a low refractive index layer is not particularly limited, and can be performed by, for example, irradiation with light or application of heat. Photo-curing of the composition for forming a low refractive index layer can be performed by irradiating it with ultraviolet light or visible light having a wavelength of 200 nm to 400 nm. The exposure dose during light irradiation is 100 mJ / cm. 2 ~4,000mJ / cm 2 The exposure time is not particularly limited either, and can be appropriately changed depending on the exposure device used, the wavelength of the irradiating light, or the exposure dose.

[0030] The anti-reflection film may further include a hard coating layer. The hard coating layer may be present between the substrate layer and the low refractive index layer. The hard coating layer can increase the hardness of the anti-reflection film. This allows the anti-reflection film to be used as an optical film located at the outermost edge of a display device, i.e., as a window film.

[0031] The refractive index range of the hard coating layer can be appropriately selected within a range that does not impair the objectives of the present application. For example, the refractive index of the hard coating layer at a wavelength of 550 nm can be 1.5 or less, 1.40 or less, or 1.30 or less. The lower limit of the refractive index can be, for example, 1.0 or more, 1.1 or more, or 1.2 or more.

[0032] The hard coating layer may be any commonly known hard coating layer without any particular limitation. The hard coating layer may include, for example, a photocurable resin. The photocurable resin may be a light-transmitting resin. The photocurable resin included in the hard coating layer is a polymer of a photocurable compound that can undergo a polymerization reaction when irradiated with light such as ultraviolet light, and may be a resin commonly used in the art. Specifically, the photocurable resin may include at least one selected from the group consisting of reactive acrylate oligomers, such as urethane acrylate oligomers, epoxy acrylate oligomers, polyether acrylates, and polyether acrylates; and the group consisting of polyfunctional acrylate monomers, such as dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, trimethylenepropyl triacrylate, propoxylated glycerol triacrylate, trimethylpropaneethoxy triacrylate, 1,6-hexanediol diacrylate, propoxylated glycerol triacrylate, tripropylene glycol diacrylate, and ethylene glycol diacrylate.

[0033] The hard coating layer may further include organic or inorganic fine particles dispersed in the photocurable resin. Specific examples of the organic or inorganic fine particles included in the hard coating layer are not limited. For example, the organic or inorganic fine particles may be one or more organic fine particles selected from the group consisting of acrylic resins, styrene resins, epoxide resins, and nylon resins, or one or more inorganic fine particles selected from the group consisting of silicon oxide, titanium dioxide, indium oxide, tin oxide, zirconium oxide, and zinc oxide. The particle size of the organic or inorganic fine particles is not specifically limited. For example, the organic fine particles may have a particle size of 1 to 10 μm, and the inorganic particles may have a particle size of 1 nm to 500 nm or 1 nm to 300 nm. The particle size of the organic or inorganic fine particles may be defined as a volume average particle size.

[0034] The thickness of the hard coating layer may be, for example, within a range of 0.1 μm to 100 μm. The pencil hardness of the anti-reflection film to which the hard coating layer is applied may be, for example, 2H or more or 4H or more. Within this range, even when the anti-reflection film is used as the outermost window film of a display device, it may be advantageous to protect the transparent display element from the outside.

[0035] The hard coating layer can be prepared by, for example, coating a composition for forming a hard coating layer on a substrate layer and curing the composition. The composition for forming a hard coating layer may include the photocurable resin and, if necessary, may further include the organic or inorganic fine particles.

[0036] The method for curing the composition for forming a hard coating layer is not particularly limited, and can be performed by, for example, irradiation with light or application of heat. Photocuring of the composition for forming a hard coating layer can be performed by irradiating it with ultraviolet light or visible light having a wavelength of 200 nm to 400 nm. The exposure dose during light irradiation is 100 mJ / cm. 2 ~4,000mJ / cm 2The exposure time is not particularly limited either, and can be appropriately changed depending on the exposure device used, the wavelength of the irradiating light, or the exposure dose.

[0037] The composition for forming a low refractive index layer or a hard coating layer may further contain a solvent. The solvent may be an organic solvent. Examples of the organic solvent include hydrocarbon, halogenated hydrocarbon, and ether solvents. Examples of hydrocarbon solvents include pentane, hexane, heptane, cyclohexane, n-decane, n-dodecane, benzene, toluene, xylene, and methoxybenzene solvents. Examples of halogenated hydrocarbon solvents include carbon tetrachloride, chloroform, 1,2-dichloroethane, dichloromethane, and chlorobenzene solvents. Examples of ether solvents include tetrahydrofuran, thioxane, and propylene glycol monomethyl ether acetate solvents.

[0038] The low refractive index layer-forming composition or the hard coating layer-forming composition may further contain any additives, such as, but not limited to, a curing agent or catalyst that assists the curing of the curable resin, an initiator such as a radical initiator or a cationic initiator, a thixotropic agent, a leveling agent, an antistatic agent, an antifoaming agent, an antioxidant, a radical generator, an organic or inorganic pigment or dye, a dispersant, various fillers such as a thermally conductive filler or an insulating filler, a functional polymer, or a light stabilizer.

[0039] The term "polarizer" as used herein refers to a film, sheet, or element having a polarizing function. A polarizer is a functional element that can extract light vibrating in one direction from incident light vibrating in various directions.

[0040] As used herein, the terms polarizer and polarizing plate refer to different objects. The term polarizer refers to a film, sheet, or element having a polarizing function, while the term polarizing plate refers to an object including other elements laminated on one or both sides of the polarizer. Examples of such other elements include, but are not limited to, a protective film for the polarizer, an anti-reflection film, a retardation film, a pressure-sensitive adhesive layer, an adhesive layer, and a surface treatment layer. The circular polarizer of the present application may or may not include a protective film attached to one or both sides of the polarizer. Even if a separate protective film is not attached to one or both sides of the polarizer, the anti-reflection film and / or retardation film can act as a protective substrate for the polarizer.

[0041] In the present application, an absorption-type linear polarizer can be used as the polarizer. A known example of such a polarizer is a PVA (poly(vinyl alcohol)) polarizer. Basically, any known polarizer can be used as the polarizer in the present application. In one example, a polarizer having the following characteristics can be used as a known PVA (poly(vinyl alcohol)) polarizer.

[0042] The transmittance of the polarizer at a wavelength of 550 nm may be within a range of 40% to 50%. Specifically, the transmittance may be within a range of 42% to 43% or 43.5% to 44.5%. The transmittance may refer to the single transmittance of the polarizer at a wavelength of 550 nm. The single transmittance of the polarizer may be measured, for example, using a spectrometer (V7100, manufactured by Jasco). For example, a polarizer sample (excluding the upper and lower protective films) is placed in the instrument, air is set as the baseline, and the axis of the polarizer sample is aligned vertically and horizontally with the axis of the reference polarizer, and the respective transmittances are measured, and then the single transmittance can be calculated.

[0043] Typically, a PVA-based absorptive linear polarizer exhibits the above-mentioned single transmittance, and such a PVA-based absorptive linear polarizer can be applied in the present application. However, the type of polarizer that can be applied is not limited to the above, as long as it exhibits the above-mentioned single transmittance.

[0044] A PVA-based polarizer generally comprises a PVA film or sheet and an anisotropic water-absorbing substance such as a dichroic dye or iodine adsorbed and oriented on the PVA film or sheet.

[0045] PVA films or sheets can be obtained, for example, by gelling polyvinyl acetate. Examples of polyvinyl acetate include homopolymers of vinyl acetate and copolymers of vinyl acetate and other monomers. Examples of other monomers copolymerized with vinyl acetate include one or more of unsaturated carboxylic acid compounds, olefin compounds, vinyl ether compounds, unsaturated sulfonic acid compounds, and acrylamide compounds having an ammonium group.

[0046] The gelation degree of polyvinyl acetate is generally about 85 mol% to about 100 mol%, or about 98 mol% to 100 mol%, and the polymerization degree of polyvinyl alcohol in the linear polarizer is generally about 1,000 to about 10,000, or about 1,500 to about 5,000.

[0047] PVA polarizers are manufactured by dyeing and stretching a PVA film or sheet, and if necessary, the manufacturing process can further include swelling, crosslinking, washing, and / or drying steps.

[0048] For example, the dyeing process is a process for adsorbing iodine, an anisotropic water-absorbing material, into a PVA film or sheet, and can be carried out by immersing the PVA film or sheet in a treatment bath containing iodine and potassium iodide. During this process, the transmittance of the single material can be adjusted by adjusting the concentrations of iodine and potassium iodide in the treatment bath.

[0049] In the dyeing process, the PVA film or sheet is immersed in a dyeing or crosslinking solution containing iodine (I2), iodides such as KI, and / or boric acid compounds (boric acid or borate salts), and during this process, anisotropic water-absorbing substances such as iodine are adsorbed onto the PVA film or sheet. Therefore, the type or amount of anisotropic water-absorbing substances adsorbed onto the polarizer during this process is determined depending on the concentration of the above compounds in the dyeing solution, which in turn determines the absorbance and transmittance of the polarizer for light of a specific wavelength.

[0050] For example, the species of iodine compounds that can be present in the staining solution are iodide (M + I - ) and iodine (I2) - , I2, I3 - or I5 - However, among the above compounds, I - The absorption wavelength range of I1 is approximately 190nm to 260nm, and the color effect is small. The absorption wavelength range of I2 is approximately 400nm to 500nm, and the color effect is mainly red. The absorption wavelength range of I3 is approximately 190nm to 260nm, and the color effect is small. - The absorption wavelength range is about 250nm to 400nm, the color is mainly yellow, and the linear structure of I5 - The absorption wavelength range is not observed, and the color impression is small. - The absorption wavelength range is approximately 500 nm to 900 nm, and the color is mainly blue.

[0051] The retardation film may have flat dispersion characteristics. In this specification, flat dispersion characteristics may refer to a characteristic in which the retardation value is constant as the wavelength increases. In one example, the flat dispersion characteristics may refer to a retardation film having an R(450) / R(550) value of 0.99 to 1.01. Furthermore, the flat dispersion characteristics may refer to a retardation film having an R(650) / R(550) value of 0.99 to 1.01. Here, R(λ) may refer to an in-plane retardation value for a wavelength of λ nm. Retardation films with flat dispersion characteristics have the advantage of being commercially available at low cost compared to retardation films with reverse dispersion characteristics. Furthermore, retardation films with flat dispersion characteristics do not require an additional coating process, which is advantageous in terms of process yield.

[0052] In this specification, the in-plane retardation value can be calculated by the following Equation 1.

[0053] [Formula 1] Rin=d×(nx-ny)

[0054] In Equation 1, Rin represents the in-plane retardation, nx and ny represent the refractive index of the retardation film in the x-axis direction and the y-axis direction, respectively, and d represents the thickness of the retardation film. These definitions may be applied throughout the present specification unless otherwise specified. The x-axis refers to the in-plane slow axis direction of the retardation film, the y-axis refers to the in-plane direction (fast axis direction) perpendicular to the x-axis, and the z-axis may refer to the normal direction of the plane formed by the x-axis and y-axis, e.g., the thickness direction of the retardation film. In this specification, the slow axis may refer to the axis parallel to the direction in which the refractive index is highest relative to the in-plane direction of the retardation film. Unless otherwise specified, the refractive index in this specification refers to the refractive index for light with a wavelength of approximately 550 nm.

[0055] The in-plane retardation value of the retardation film at a wavelength of 550 nm may be 135 nm to 142 nm. Specifically, the in-plane retardation value of the retardation film at a wavelength of 550 nm may be within a range of 135 nm to 137.5 nm. Within this range, a flat-dispersion retardation film may be used, which may be suitable for improving reflective visibility.

[0056] Methods for adjusting the in-plane retardation value of a retardation film are known. In one example, when the retardation film is a stretched polymer film, the in-plane retardation value can be adjusted by adjusting the material, thickness, and stretching ratio of the polymer film. In another example, when the retardation film is a liquid crystal polymer film, the in-plane retardation value can be adjusted by adjusting the thickness of the liquid crystal layer, the birefringence value of the liquid crystal, etc.

[0057] The slow axis of the retardation film may form an angle of 37 to 43 degrees with the absorption axis of the polarizer. Specifically, the angle may be 37 degrees or more, 37.5 degrees or more, 38 degrees or more, 38.5 degrees or more, 39 degrees or more, 39.5 degrees or more, or 40 degrees or more, and 43 degrees or less or 42.5 degrees or less. This may improve the reflective luminance of a circular polarizer using a flat dispersion retardation film. In this specification, the angle between the A axis and the B axis may include both the angle between the A axis in a clockwise direction and the angle between the A axis in a counterclockwise direction, with the B axis at 0 degrees.

[0058] The thickness of the retardation film may be, for example, in the range of 10 μm to 100 μm when it is a polymer stretched film. In another example, the thickness of the retardation film may be, for example, in the range of 0.1 μm to 5 μm when it is a liquid crystal polymer film.

[0059] The retardation film may be a liquid crystal polymer film or a stretched polymer film. Specifically, the retardation film may be a stretched polymer layer obtained by stretching a polymer film that can be given optical anisotropy by stretching in an appropriate manner, or a liquid crystal layer. The liquid crystal layer may be a liquid crystal polymer layer or a cured layer of a polymerizable liquid crystal compound.

[0060] The liquid crystal polymer film may include a substrate layer and a liquid crystal layer on one side of the substrate layer. The same description of the substrate layer of the anti-reflection film may be applied to the substrate layer of the liquid crystal polymer film. Therefore, the substrate layer of the liquid crystal polymer film may also be a light-transmitting substrate. The liquid crystal layer may include a polymerizable liquid crystal compound in a polymerized state. As used herein, the term "polymerizable liquid crystal compound" refers to a compound containing a moiety capable of exhibiting liquid crystallinity, such as a mesogen backbone, and one or more polymerizable functional groups. Such polymerizable liquid crystal compounds are variously known as reactive mesogens (RMs). The polymerizable liquid crystal compound may be in a polymerized form within the cured layer, i.e., contained in the aforementioned polymerization unit, which may refer to a state in which the liquid crystal compound is polymerized to form a backbone such as a main chain or side chain of a liquid crystal polymer within the cured layer.

[0061] The polymerizable liquid crystal compound may be a monofunctional or polyfunctional polymerizable liquid crystal compound. The monofunctional polymerizable liquid crystal compound is a compound having one polymerizable functional group, and the polyfunctional polymerizable liquid crystal compound is a compound having two or more polymerizable functional groups. For example, the polyfunctional polymerizable liquid crystal compound may have 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 2 to 3, or 2 or 3 polymerizable functional groups.

[0062] It is known that the above-mentioned polymerizable liquid crystal compound is blended with other components such as an initiator, a stabilizer, and / or a non-polymerizable liquid crystal compound to prepare a polymerizable liquid crystal composition, which is then cured in an aligned state on an alignment film to form the cured layer exhibiting birefringence. The retardation film having the above-mentioned flat dispersion characteristic can be prepared by including a polymerizable liquid crystal compound having the above-mentioned flat dispersion characteristic.

[0063] The polymer stretched film may be, for example, a polymer layer containing, as a polymer material, polyolefins such as polyethylene or polypropylene, cycloolefin polymers (COP) such as polynorbornene, polyesters such as polyvinyl chloride, polyacrylonitrile, polysulfone, acrylic resin, polycarbonate, and polyethylene terephthalate, cellulose ester polymers such as polyacrylate, polyvinyl alcohol, and TAC (Triacetyl cellulose), or copolymers of two or more monomers among the monomers that form the above polymers.

[0064] The method for obtaining a polymer stretched film is not particularly limited. For example, it can be obtained by molding the polymer material into a film and then stretching it. The method for forming the film is not particularly limited, and film can be formed by known methods such as injection molding, sheet molding, blow molding, injection blow molding, inflation molding, extrusion molding, foam molding, and cast molding. Secondary processing methods such as pressure molding and vacuum forming can also be used. Among these, extrusion molding and cast molding are preferred. In this case, an unstretched film can be extruded using an extruder equipped with, for example, a T-die or a circular die. When obtaining a molded product by extrusion molding, a material in which various resin components and additives have been melt-kneaded in advance can be used, or the material can be formed by melt-kneading during extrusion molding. Alternatively, an unstretched film can be cast-molded by dissolving the various resin components in a solvent common to the various resin components, such as chloroform or methylene dichloride, followed by casting, drying, and solidifying.

[0065] The polymer stretched film can be produced by uniaxially stretching the above-mentioned formed film in the mechanical direction or in the transverse direction (TD, horizontal or width direction) perpendicular to the mechanical direction (MD, Mechanical Direction, machine direction or length direction). Alternatively, a biaxially stretched film may be produced by stretching the film using a method such as sequential biaxial stretching by roll stretching and tenter stretching, simultaneous biaxial stretching by tenter stretching, or biaxial stretching by tubular stretching.

[0066] The retardation value of a stretched polymer film can generally be controlled by adjusting the stretching conditions. This is because the retardation value depends on the thickness of the film itself as a result of stretching. In the case of biaxial stretching, the ratio of the stretching ratio in the mechanical flow direction (MD) to the direction perpendicular to the mechanical flow direction (TD) (MD / TD) is preferably 0.67 or less or 1.5 or more, more preferably 0.55 or less or 1.8 or more, and most preferably 0.5 or less or 2 or more.

[0067] The adhesive layer may function to attach the circular polarizer to the display panel. The adhesive layer may include an adhesive resin. For example, a light-transmitting adhesive resin may be used as the adhesive resin. For example, an adhesive resin may be used that allows the adhesive layer formed from the adhesive resin to have a transmittance of about 80% or more, 85% or more, 90% or more, or 95% or more for wavelengths of 380 nm to 780 nm. The transmittance may refer to the percentage of the amount of light transmitted through the adhesive layer relative to the amount of light incident on the adhesive layer. The adhesive resin may include, for example, any one or more selected from the group consisting of acrylic resins, silicone resins, ester resins, urethane resins, amide resins, ether resins, fluorine-based resins, and rubber resins.

[0068] The thickness of the adhesive layer may be, for example, within the range of 15 μm to 30 μm.

[0069] The method for forming the pressure-sensitive adhesive layer on one side of the retardation film is not particularly limited. In one example, the pressure-sensitive adhesive layer may be formed by applying a pressure-sensitive adhesive composition containing the pressure-sensitive adhesive resin to a release film to form a pressure-sensitive adhesive layer, transferring the pressure-sensitive adhesive layer to one side of the retardation film, and removing the release film. In another example, the pressure-sensitive adhesive layer may be formed by directly applying the pressure-sensitive adhesive composition to one side of the retardation film.

[0070] The circular polarizer may contain a dye, which functions to adjust the transmittance of the circular polarizer. In this specification, the dye may refer to a substance that can intensively absorb and / or transform light in at least a part or all of the visible light range, for example, a wavelength range of 380 nm to 780 nm.

[0071] A circular polarizer containing the dye may have a transmittance of 30% or less or 28% or less at a wavelength of 430 nm. By satisfying this transmittance range, a circular polarizer can contribute to a neutral reflected color, thereby improving the reflective visual sensation even when using a retardation film with flat dispersion characteristics. More specifically, a circular polarizer containing the dye may have a transmittance of 35% or more or 40% or more at wavelengths of 460 nm and 550 nm, respectively.

[0072] The lower limit of the transmittance of the dye-containing circular polarizer at a wavelength of 430 nm may be 4% or more. If the transmittance is too low, the color change of the white light emitted from the OLED becomes too large, so the lower limit of the transmittance of the dye-containing adhesive layer is preferably within the above range.

[0073] The dye may be appropriately selected within a range that enables the circular polarizer to exhibit the above transmittance characteristics. The dye may, for example, be a dye that exhibits absorption in the blue region. The dye may exhibit maximum absorbance in the blue region. In this specification, the absorption or absorbance of the dye may be determined from a transmittance spectrum measured for a layer formed by mixing the dye with a light-transmitting resin. In this specification, the light-transmitting resin may refer to a layer formed of the resin alone, having a transmittance of about 80% or more, 85% or more, 90% or more, or 95% or more for wavelengths of 380 nm to 780 nm.

[0074] A dye having the above absorption characteristics may be referred to herein as a blue cut dye. The blue region may be, for example, within a wavelength range of 370 nm to 430 nm. Therefore, a circular polarizer containing the dye may also exhibit maximum absorbance within a wavelength range of 380 nm to 780 nm, within a wavelength range of 370 nm to 430 nm. Since the dye absorbs in the blue region, it can exhibit a yellow color. The dye may be a single dye or a mixture of two or more dyes within a range that allows the circular polarizer to exhibit the above transmittance characteristics.

[0075] The dye may be one or more dyes selected from the group consisting of anthraquinone dyes, methine dyes, azomethine dyes, oxazine dyes, azo dyes, styryl dyes, coumarin dyes, porphyrin dyes, dibenzofuranone dyes, diketopyrrolopyrrole dyes, rhodamine dyes, xanthene dyes, and pyrromethene dyes.

[0076] The dye may be contained in any layer contained in the circular polarizer as long as the circular polarizer can exhibit the above transmittance.

[0077] For example, the dye may be included in one or more of the antireflection film, the retardation film, and the adhesive layer. In one example, the dye may be included in the antireflection film. As described above, the antireflection film may include a substrate layer and a low refractive index layer on one side of the substrate layer. In this case, the dye may be included in the substrate layer of the antireflection film. Alternatively, as described above, the antireflection film may further include a hard coating layer between the substrate layer and the low refractive index layer. In this case, the dye may be included in the hard coating layer of the antireflection film. In one example, the dye may be included in the retardation film. As described above, when the retardation film is a liquid crystal polymer film, the retardation film may include a substrate layer and a liquid crystal layer on one side of the substrate layer. In this case, the dye may be included in the substrate layer of the retardation film. On the other hand, when the retardation film is a stretched polymer film, the dye may be included in the stretched polymer film. In one example, the dye may be included in the adhesive layer.

[0078] In another example, the circular polarizer may further include a separate layer for incorporating a dye, in addition to the antireflection film, retardation film, and adhesive layer. Such a separate layer may also contain the dye while containing a light-transmitting resin as a main component. The location of the separate layer is not particularly limited, and the separate layer may be formed on one or both sides of the antireflection film, polarizer, retardation film, or adhesive layer. However, since the adhesive layer is used to attach the circular polarizer to a panel, it is preferable that the separate layer is not present on the panel-attaching surface of the adhesive layer.

[0079] The dye-containing layer may have a transmittance of 75% or less, 70% or less, 65% or less, or 60% or less at a wavelength of 430 nm. By satisfying this transmittance range, the dye-containing layer can contribute to a neutral reflected color, thereby improving the reflective luminance even when using a retardation film with flat dispersion characteristics. More specifically, the dye-containing layer may have a transmittance of 90% or more at wavelengths of 460 nm and 550 nm. The lower limit of the transmittance of the dye-containing layer at a wavelength of 430 nm may be 10% or more. If the transmittance is too low, the color change of the white light emitted by the OLED will be excessively large, so it is preferable that the lower limit of the transmittance of the dye-containing layer be within the above range.

[0080] The dye content in the dye-containing layer may be appropriately selected within a range that enables the circular polarizer to exhibit the above transmittance characteristics. As described above, the dye-containing layer may contain a light-transmitting resin as a main component and further contain the above dye. The dye content in the dye-containing layer may be, for example, in the range of 0.5 to 10 parts by weight per 100 parts by weight of the light-transmitting resin. A dye content within this range may be appropriate for improving the reflective luminance of the circular polarizer, and as the dye content within this range increases, the desired reflected color can be achieved. However, if the dye content is too high, the solubility of the dye may be insufficient, causing precipitation and affecting the physical properties of each layer; therefore, it is preferable to adjust the dye content within this range.

[0081] When the weight of the dye in a dye-containing layer is the same, the same transmittance characteristics can be obtained even if the thickness of the dye-containing layer is changed. Therefore, to increase the transmittance of a dye-containing layer within the aforementioned range, there are two methods: either to fix the thickness of the dye-containing layer and reduce the weight of the dye to lower the dye concentration, or to reduce the thickness of a dye-containing layer with the same dye concentration to lower the weight of the dye.

[0082] The present application also relates to a display device including the circular polarizer, such as an OLED (Organic Light Emitting Diode) device.

[0083] 3 shows an example of an OLED device of the present application. As shown in FIG. 3, the OLED device may include an OLED panel 200 and a circular polarizer 100 disposed on one side of the OLED panel. The OLED panel and the circular polarizer may be attached to each other via an adhesive layer 40.

[0084] The OLED panel may include a substrate, a lower electrode, an organic light-emitting layer, and an upper electrode, in that order. The organic light-emitting layer may include an organic material that can emit light when a voltage is applied to the lower electrode and the upper electrode. One of the lower electrode and the upper electrode may be an anode, and the other may be a cathode. The anode is an electrode into which holes are injected and may be made of a conductive material with a high work function, while the cathode is an electrode into which electrons are injected and may be made of a conductive material with a low work function. Typically, the anode may be a transparent metal oxide layer with a high work function, such as ITO or IZO, and the anode may be a metal electrode with a low work function. Since organic light-emitting layers are generally transparent, a transparent display can be achieved by making the upper and lower electrodes transparent. In one example, a transparent display can be achieved by making the metal electrodes very thin.

[0085] The OLED panel may further include an encapsulation substrate on the upper electrode that prevents moisture and / or oxygen from entering from the outside. Additional layers may be included between the lower electrode and the organic light-emitting layer and between the upper electrode and the organic light-emitting layer. The additional layers may include, but are not limited to, a hole transporting layer, a hole injection layer, an electron injection layer, and an electron transporting layer for balancing electrons and holes.

[0086] The circular polarizer can be disposed on the side where light exits from the OLED element. For example, in the case of a bottom emission structure where light exits the base substrate, the circular polarizer can be disposed on the outside of the base substrate. In the case of a top emission structure where light exits the encapsulation substrate, the circular polarizer can be disposed on the outside of the encapsulation substrate. The circular polarizer can improve visibility and display performance by preventing external light from being reflected by a reflective layer made of metal, such as the electrodes and wiring of the OLED panel, and exiting the OLED panel.

[0087] In one example, the OLED panel may further include a substrate on which a color filter is formed. The substrate on which the color filter is formed may be disposed on the side of the OLED panel opposite the side on which the metal electrode is disposed. In this case, the OLED panel may have a structure including, in order, a substrate on which a color filter is formed, a transparent metal oxide electrode (anode), an emitting layer, a metal electrode (cathode), and a base substrate. The color filter may include red, green, and blue regions and may further include a black matrix to separate the regions. When the color filter is present on the substrate of the OLED panel, it may exhibit lower reflectance than when no color filter is present. Specifically, when the red, green, and blue color filters are disposed in front of the OLED emitting layer, this is to reduce the high reflectance of the metal electrode disposed on the back surface of the emitting layer.

[0088] The OLED panel may have an average reflectance of 45% or less in the 410 nm to 500 nm region. The OLED panel may have an average reflectance of 20% or more in the 410 nm to 500 nm region. Furthermore, the OLED panel may have an average reflectance of 50% or less in the 600 nm to 650 nm region. The OLED panel may have an average reflectance of 20% or more in the 600 nm to 650 nm region. Through the application of such an OLED panel, it may be further advantageous to improve reflective visibility by using a retardation film with flat dispersion characteristics.

[0089] As described above, an OLED device incorporating the circular polarizer of the present application in an OLED panel can exhibit excellent reflective luminance. In one example, the reflectance at 550 nm of the OLED panel to which the circular polarizer is attached can be 2.0% or less, 1.9% or less, 1.8% or less, or 1.7% or less. The lower the reflectance of the OLED panel to which the circular polarizer is attached, the better the reflective luminance. The lower the reflectance, the greater the reflective luminance. The lower the reflectance, but the lower limit is not particularly limited, and can be, for example, 0.1% or more.

[0090] In one example, the reflective color of the OLED panel to which the circular polarizer is attached is L * a * b * Color coordinate standard a * Value less than 8b * The value may be greater than -8.5. * Specifically, the value may be 7.75 or less, 7.5 or less, 7.25 or less, 7 or less, 6.75 or less, 6.5 or less, or 6.25 or less. * Specifically, the value may be -8.3 or more, -8 or more, -7.5 or more, -7 or more, -6.6 or more, -6 or more, -5 or more, or -4 or more. * The lower limit of is greater than 0, and the above b * The upper limit of a may be less than 0. When the reflectance and reflected color of the OLED panel to which the circular polarizer is attached are within the above ranges, it can be said that the reflective luminance is excellent. * and b * Among the values, especially a * The range of values ​​may be more important because the reflected color of red light generally reduces the viewer's visibility more than that of blue light. In addition, when the reflectance of the OLED panel for the 550 nm wavelength is set within the above range, a * and b * Even if the absolute value of r increases, the image appears blacker, which can be more advantageous in improving the reflective visibility. [Effects of the Invention]

[0091] The present application can provide a circular polarizer capable of improving reflected color using a retardation film having flat dispersion characteristics, and an OLED device including the circular polarizer. [Brief explanation of the drawings]

[0092] [Figure 1] 1 is a diagram illustrating an example of a circular polarizing plate of the present application. [Figure 2] 1 is a diagram showing an example of a reflectance spectrum of an anti-reflection film. [Figure 3] 1 is a diagram illustrating an exemplary OLED device of the present application. [Figure 4] 1 is a graph showing the results of measuring the transmittance of the circular polarizing plates of Comparative Example 18 and Example 4. [Figure 5] 10 is a diagram showing the results of evaluating the light-emitting characteristics of an OLED panel in Evaluation Example 2. [Figure 6] 10 is a graph showing the reflectance spectrum of the OLED panel of Evaluation Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0093] Hereinafter, the present application will be described in detail through examples according to the present application and comparative examples not in accordance with the present application, but the scope of the present application is not limited by the examples presented below.

[0094] [Examples 1 to 3 and Comparative Examples 1 to 17] (Circular polarizer) A circularly polarizing plate including an anti-reflection film, a polarizer, a retardation film, and a pressure-sensitive adhesive layer in this order was prepared.

[0095] The anti-reflection film was fabricated by coating a triacetyl cellulose (TAC) substrate film with a hard coating layer approximately 5 μm thick, and then coating the hard coating layer with a low refractive index layer containing hollow silica nanoparticles. The low refractive index layer had a refractive index of approximately 1.3-1.4 at a wavelength of 550 nm and a thickness of approximately 70-150 nm. The anti-reflection film had a reflectance of approximately 0.1-0.9% at a wavelength of 550 nm, a haze of approximately 0.01-0.5%, a minimum reflection wavelength of 510 nm, and a minimum reflectance of 0.8%.

[0096] The retardation film was a product produced by Zeon Corporation by obliquely stretching a COP film, and had an R(450) / R(550) value of 1. The in-plane retardation value for a wavelength of 550 nm and the slow axis of the retardation film relative to the light absorption axis of the polarizer were changed as shown in Table 1 below to prepare circularly polarizing plates of Comparative Examples 2 to 17 and Examples 1 to 3.

[0097] Two types of polarizers are used: a PVA-based polarizer with a transmittance of 42.5% and a PVA-based polarizer with a transmittance of 44%.

[0098] The adhesive layer is laminated onto the retardation film using a product coated between release films. A commercially available acrylic adhesive for polarizers was used for the adhesive layer, and samples were prepared as shown in Table 1 below, depending on whether the adhesive layer contained a blue-cut dye. The adhesive layer containing the blue-cut dye had a transmittance of 60% at 430 nm and a transmittance of 90% or more at 460 nm and 550 nm. The blue-cut dye was a mixture of two dyes with different maximum absorption wavelengths in the blue region: Eusorb UV-390 and Eusorb UV-1990 from Eutec Chemical Co., Ltd.

[0099] In Table 1 below, Comparative Example 1 is a flat dispersion film, a ZD product from Zeon Corporation, with an in-plane retardation of 130 nm for a wavelength of 550 nm and an R(450) / R(550) value of 1.0.

[0100] (OLED panel) The circular polarizer was attached to an OLED panel manufactured by LGD, which has an average reflectance of 40% for wavelengths ranging from 410 nm to 550 nm and an average reflectance of 48% for wavelengths ranging from 600 nm to 650 nm.

[0101] [Evaluation Example 1. Evaluation of reflected light depending on the configuration of the circular polarizer] The reflective luminance of the OLED panels to which the circular polarizers of the above examples and comparative examples are attached is evaluated according to the configuration of the circular polarizer. At this time, the OLED panel is in an electric field off state. Specifically, the L * a * b * The color coordinates were measured under a D65 light source environment. * a * b * Color coordinate standard a * is less than 8 and b * If the value exceeds -8.5, the reflective visibility can be evaluated as excellent.

[0102] The retardation value and optical axis of the retardation film are determined using Axoscan equipment manufactured by Axometrics, and the transmittance and absorption axis of the polarizer are determined using V-7100 Spectrophotometer equipment manufactured by Jasco.

[0103] The transmittance of an adhesive layer containing blue-cut dye was measured using a Shimadzu UV-3600. Specifically, the adhesive containing blue-cut dye was attached to a glass substrate, and then a transparent PET film was attached to the exposed adhesive surface. To set the baseline of the equipment before measuring the sample, a sample with the same structure as the measurement sample but containing a transparent adhesive instead of the adhesive containing blue-cut dye was loaded. As a result, the transmittance of the measured sample was measured under conditions that did not include reflectance, and therefore the transmittance in the wavelength range where there is no dye absorption is 100%.

[0104] The reflectance of the anti-reflection film was measured by attaching a light-absorbing black tape to the backside of the anti-reflection coating layer of the substrate, and then measuring the specular reflectance of the surface layer of the anti-reflection coating layer using Minolta's CM-2600d equipment. Specifically, the reflectance was calculated by subtracting the SCE (Specular Component Excluded) value from the SCI (Specular Component Included) value among the values ​​measured by the equipment. When measuring reflectance, differences in the measured values ​​were observed depending on the absorption axis direction of the polarizer, so measurements were taken with the length direction of the measuring device and the absorption axis direction of the polarizer horizontal. Haze was measured using Murakami Color Research Laboratory's HM-150 equipment. L * a * b * The color coordinates were measured using Minolta's CM-2600d equipment by attaching a circular polarizer to an OLED panel and measuring the reflectance and reflected color according to the CIE 1964 / 10° standard under D65 light source conditions. The evaluation results for reflected luminance are shown in Table 1. In Table 1 below, Y(D65) means luminous reflectance (%), and R@(550) means reflectance at 550nm (%). The transmittance of the circular polarizer was measured using Jasco's V-7100 Spectrophotometer.

[0105] [Table 1]

[0106] [Example 4] A circularly polarizing plate including an anti-reflection film, a polarizer, a retardation film, and a pressure-sensitive adhesive layer in this order was prepared, and was the same as in Example 1 except for the configurations described below.

[0107] The retardation film has a retardation value of 137.5 nm for a wavelength of 550 nm, and is attached so that the slow axis of the retardation film forms an angle of 42.5 degrees with the light absorption axis of the polarizer.

[0108] The polarizer used was a PVA-based polarizer with a transmittance of 42.5%.

[0109] The adhesive layer contains a blue-cut dye, and the adhesive layer containing the blue-cut dye has a transmittance of 71% for a wavelength of 430 nm, and a transmittance of 90% or more for wavelengths of 460 nm and 550 nm, respectively.

[0110] The circular polarizer was attached to an OLED panel, which was the same as in Example 1.

[0111] [Comparative Example 18] A circular polarizer was manufactured in the same manner as in Example 4, except that the blue-cut dye was not applied to the adhesive layer. The circular polarizer was attached to an OLED panel, which was the same as in Example 1.

[0112] Figure 4 shows the transmittance measurement results for the circular polarizers of Comparative Example 18 and Example 4. The transmittance was measured for the circular polarizer itself before it was attached to the OLED panel. Figures 4(a) and 4(b) show the same experimental results, but with different wavelength ranges on the x-axis (a: 400-500 nm, b: 400-700 nm). Example 4 exhibited a transmittance of approximately 27% for a wavelength of 430 nm, approximately 40% for a wavelength of 460 nm, and approximately 43% for a wavelength of 550 nm. Comparative Example 18 exhibited a transmittance of approximately 38% for a wavelength of 430 nm, approximately 40% for a wavelength of 460 nm, and approximately 43% for a wavelength of 550 nm.

[0113] [Evaluation example 2. Effect of blue cut dye on OLED light-emitting properties] After attaching the circular polarizers of Example 4 and Comparative Example 18 to OLED panels, the effect of the blue cut dye on the luminescence characteristics was evaluated. Using a Minolta Spectroradiometer CS-1000, the u'v' coordinates of the white color were measured for the OLED panels with the circular polarizer of Comparative Example 18 (without the blue cut dye) and the circular polarizer of Example 4 (with the blue cut dye). The results showed that while there was no effect on the brightness of the OLED panel's emission after applying the blue cut dye, there was a slight change in the white color. The change in the white color can be seen as a shift from (0.216, 0.434) to (0.217, 0.436) on the u'v' coordinates. As the concentration of the blue cut dye increased, the white color coordinates shifted more, and the reflected color shifted toward neutral.

[0114] Figure 5 shows the transmittance characteristics of the adhesive layer containing the blue cut-off die and the emission characteristics of the OLED panel with and without the blue cut-off die. The use of the blue cut-off die is classified according to whether the circular polarizer of Example 4 is attached to the OLED panel or whether the circular polarizer of Comparative Example 18 is attached to the OLED panel. Figure 5 confirms that the use of the blue cut-off die does not affect the brightness of the OLED panel.

[0115] Figure 6 shows the reflectance spectra of an OLED panel using the circular polarizer of Example 4 and an OLED panel using the circular polarizer of Comparative Example 18. The reflectance spectra were measured using a Minolta CM-2600d device with the circular polarizer attached to the OLED panel. Figure 6 shows that the reflected color shifts to neutral when the blue cut dye is applied. [Explanation of symbols]

[0116] 10: Anti-reflective film 20: Polarizer 30: Phase difference film 40: Adhesive layer

Claims

1. 1. An OLED device comprising an OLED panel and a circular polarizer disposed on one side of the OLED panel, The OLED panel includes a substrate on which a color filter is formed, the circular polarizing plate includes an antireflection film, a polarizer, a retardation film having an R(450) / R(550) value of 1 to 1.01 and a slow axis that forms an angle of 37 to 43 degrees with the absorption axis of the polarizer, and a pressure-sensitive adhesive layer, in that order; and the circular polarizing plate has a transmittance of 30% or less at a wavelength of 430 nm, The OLED device, wherein the circular polarizer further comprises a dye that exhibits a maximum absorbance at a wavelength in the range of 370 nm to 430 nm (R(λ) is the in-plane retardation value for a λ nm wavelength).

2. 10. The OLED device of claim 1, wherein the anti-reflective film has a haze of 1% or less.

3. 3. The OLED device of claim 1, wherein the minimum reflection wavelength of the anti-reflection film is in the range of 400 nm to 530 nm.

4. 4. The OLED device of claim 1, wherein the transmittance of the polarizer for a wavelength of 550 nm is in the range of 40% to 50%.

5. 5. The OLED device according to claim 1, wherein the retardation film has an in-plane retardation value of 135 nm to 142 nm at a wavelength of 550 nm.

6. 6. The OLED device according to claim 1, wherein the retardation film is a liquid crystal polymer film or a polymer stretched film.

7. 7. The OLED device according to claim 1, wherein the circular polarizer has a transmittance of 40% or more for wavelengths of 460 nm and 550 nm.

8. 8. The OLED device according to claim 1, wherein the circular polarizer has a transmittance of 4% or more for a wavelength of 430 nm.

9. 9. The OLED device according to claim 1, wherein the OLED panel has an average reflectance of 45% or less for wavelengths in the range of 410 nm to 500 nm and an average reflectance of 50% or less for wavelengths in the range of 600 nm to 650 nm.

10. 10. The OLED device according to claim 1, wherein the reflectance of the OLED panel to which the circular polarizer is attached at a wavelength of 550 nm is 1.7% or less.

11. The reflective color of the OLED panel to which the circular polarizer is attached is L. ＊ a ＊ b ＊ In terms of color coordinates, a ＊ <8 and b ＊ The OLED device according to any one of claims 1 to 10, wherein the OLED device satisfies >-8.5.

Images