Vertical polarizing plate

Abstract

To provide a vertical polarizing plate (1) capable of minimizing the reduction in polarizing performance even when incorporated into the viewing side of an organic EL image display device and used outdoors.SOLUTION: A vertical polarizing plate (1) of the present invention comprises an ultraviolet absorbing film (2), an oxygen barrier layer (3), and a vertical polarizing film (4) having a dichroic dye vertically oriented therein, laminated in the described order, where a portion from the ultraviolet absorbing film (2) to the oxygen barrier layer (3) has a light transmittance of 10% or less at a 380 nm wavelength.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vertical polarizer. [Background technology]

[0002] A vertical polarizing film (optically absorptive anisotropic film) is known, which is made of a cured product obtained by curing a composition containing a polymerizable liquid crystal compound and a dichroic dye, and in which the dichroic dye is oriented in the vertical direction (thickness direction) [Patent Document 1]. Because the dichroic dye is oriented in the vertical direction, this vertical polarizing film transmits, for example, linearly polarized light whose vibration plane is in-plane, while absorbing linearly polarized light that vibrates perpendicular to the in-plane direction. Such vertical polarizing films are often incorporated, for example, on the viewing side of organic electroluminescence (EL) image display devices and used outdoors. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-176121 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it has been found that when an organic EL image display device incorporating a vertical polarizing film on the viewing side is used outdoors, the polarization performance of the vertical polarizing film is likely to deteriorate. Therefore, the present inventors have conducted extensive research to obtain a vertical polarizing plate that can suppress deterioration in polarization performance even when incorporated into the visible side of an organic EL image display device and used outdoors. As a result, they have found that by laminating an oxygen barrier layer together with a UV absorbing film on a vertical polarizing film, the light transmittance (T 380 ) to 10% or less, the inventors have found that such problems can be solved, and have arrived at the present invention. [Means for solving the problem]

[0005] That is, the present invention provides: an ultraviolet absorbing film; an oxygen barrier layer; a vertical polarizing film in which a dichroic dye is vertically oriented, and a vertical polarizing film in which a dichroic dye is vertically oriented are laminated in this order directly or via an adhesive layer; The direction of any position on the film surface is the x-axis, the direction perpendicular to the x-axis on the film surface is the y-axis, and the x-axis and y When the film thickness direction perpendicular to the axis is defined as the z-axis, the following equations (1) to (3): Az>(Ax+Ay) / 2 (1) Ax(z=60°) / Ax>5 (2) Ay(z=60°) / Ay>5 (3) [In formulas (1) to (3), Ax, Ay, Az, Ax(z=60°) and Ay(z=60°) are all absorbances at the absorption maximum wavelength of the dichroic dye in the optically absorptive anisotropic film, Ax represents the absorbance of linearly polarized light oscillating in the x-axis direction, Ay represents the absorbance of linearly polarized light vibrating in the y-axis direction, Az represents the absorbance of linearly polarized light vibrating in the z-axis direction, Ax(z=60°) represents the absorbance of linearly polarized light oscillating in the x-axis direction when the film is rotated 60° around the y-axis, Ay (z = 60°) represents the absorbance of linearly polarized light oscillating in the y-axis direction when the film is rotated 60° around the x-axis. Satisfied, The light transmittance (T 380 ) is 10% or less. [Effects of the Invention]

[0006] The vertical polarizing plate of the present invention has an oxygen barrier layer and an ultraviolet absorbing film laminated in this order on a vertical polarizing film, and further has a light transmittance (T 380) is 10% or less, so even if the vertical polarizing film is incorporated into the viewing side of an organic EL image display device and used outdoors, the deterioration of the polarization performance of the vertical polarizing film is suppressed. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a vertical polarizing plate of the present invention. [Figure 2] FIG. 2 is a cross-sectional view schematically illustrating an example of a composite linear polarizing plate in which a linear polarizing plate is laminated on the vertical polarizing film side of the vertical polarizing plate of the present invention. [Figure 3] FIG. 2 is a cross-sectional view showing an example of a circularly polarizing plate in which a retardation plate is laminated on the linearly polarizing plate side of a composite linear polarizing plate including a vertical polarizing plate of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] As shown in FIG. 1, the vertical polarizing plate (1) of the present invention comprises a laminate of an ultraviolet absorbing film (2), an oxygen barrier layer (3), and a vertical polarizing film (4).

[0009] [UV absorbing film] The ultraviolet absorbing film (2) is a film that absorbs ultraviolet rays but transmits visible light. The ultraviolet absorbing film is usually transparent and colorless. The ultraviolet absorbing film (2) can be, for example, a resin film obtained by molding a resin composition containing a thermoplastic resin and an ultraviolet absorber into a film. Such ultraviolet absorbing films can also be commercially available.

[0010] The ultraviolet absorbing film (2) has a light transmittance (T 300G ) is 1% or less, and the light transmittance at a wavelength of 380 nm (T 380G ) is 10% or less, and the light transmittance at a wavelength of 400 nm (T 400G ) is 20% or less, and the light transmittance at a wavelength of 450 nm (T 450G) is preferably 80% or more. When the light transmittance of the ultraviolet-absorbing film (2) is within the above range, ultraviolet rays reaching the vertical polarizing film (4) can be suppressed, and deterioration of the polarization performance can be suppressed.

[0011] The ultraviolet absorbing film (2) has a light transmittance (T 400G ) to the light transmittance at a wavelength of 450 nm (T 450G ) ratio (T 450G / T 400G ) is preferably 10 or more, more preferably 30 or more. 450G / T 400G ) is usually 100,000 or less. When the ultraviolet absorbing film (2) has such a ratio (T 450G / T 400G ), it can adequately block the so-called near ultraviolet (400 nm), which is the ultraviolet light closest to visible light, while also allowing sufficient transmission of light around 450 nm, which is the visible light closest to ultraviolet light.

[0012] The ultraviolet-absorbing film (2) may be a film in which an ultraviolet-absorbing layer (22) is formed on one or both sides of a substrate film (21) made of a thermoplastic resin or the like, as shown in Fig. 1. The ultraviolet-absorbing layer (22) is, for example, a cured product layer of a curable composition in which an ultraviolet absorber is blended with a curable resin. Such a cured product layer can be formed by applying a curable resin composition to a substrate film to obtain a coating film, and then curing this coating film.

[0013] [Base film] Examples of the substrate film (21) include plastics such as polyolefins such as polyethylene, polypropylene, and norbornene-based polymers; cyclic olefin-based resins; polyvinyl alcohol; polyethylene terephthalate; polymethacrylic acid esters; polyacrylic acid esters; cellulose esters such as triacetyl cellulose, diacetyl cellulose, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyether sulfone; polyether ketone; polyphenylene sulfide; and polyphenylene oxide. Among these, from the viewpoint of transparency and the like when used in optical film applications, a film substrate selected from any of triacetyl cellulose, cyclic olefin-based resins, polymethacrylic acid esters, and polyethylene terephthalate is more preferred.

[0014] The thickness of the base film (21) is usually 5 μm to 200 μm, preferably 7 μm to 100 μm, and more preferably 10 to 50 μm.

[0015] [Curable resin composition] [Curable resin] The curable resin constituting the curable resin composition is a resin that can form a cured product layer by curing with heat or light. Specific examples include organic hard coat materials such as organic silicone-based, melamine-based, epoxy-based, (meth)acrylic-based, and urethane (meth)acrylate-based materials, and inorganic hard coat materials such as silicon dioxide. Among these, urethane (meth)acrylate-based or polyfunctional (meth)acrylate-based curable resins are preferably used from the viewpoints of adhesion and hardness.

[0016] [Ultraviolet absorber] Examples of the ultraviolet absorber that can be incorporated into the curable resin composition include benzotriazole-based ultraviolet absorbers and hydroxyphenyltriazine-based ultraviolet absorbers.

[0017] The content of the ultraviolet absorber in the curable resin composition is usually 1 part by weight or more, preferably 3 parts by weight or more, and more preferably 5 parts by weight or more, relative to 100 parts by weight of the curable resin, in order to facilitate sufficient absorption of ultraviolet rays. In order to facilitate avoiding the phenomenon known as bleed-out, in which the ultraviolet absorber seeps out of the ultraviolet absorbing layer, the content is usually 30 parts by weight or less, preferably 15 parts by weight or less, and more preferably 5 parts by weight or less.

[0018] [From UV absorbing film to oxygen barrier layer] The ultraviolet absorbing film to the oxygen barrier layer may be formed, for example, by a compound represented by the following formula (XI): [ka] It is preferable that the compound (XI) is represented by the following formula:

[0019] In the above formula (XI), A represents a methylene group, a secondary amino group, an oxygen atom, or a sulfur atom. From the viewpoint of exhibiting high light selective absorption, A preferably represents a methylene group, a secondary amino group, or an oxygen atom.

[0020] In the above formula (XI), R 1 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. R 1 represents an alkyl group having preferably 1 to 8 carbon atoms, more preferably 1 to 5 carbon atoms, and even more preferably 1 to 3 carbon atoms, from the viewpoint of exhibiting high light-selective absorption. Here, when the alkyl group has at least one methylene group, at least one of the methylene groups may be substituted with an oxygen atom or a sulfur atom. Examples of such alkyl groups include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, an n-hexyl group, an n-octyl group, an n-decyl group, a methoxy group, an ethoxy group, and an isopropoxy group.

[0021] In the above formula (XI), R 2 and R 3 R each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.2 and R 3 From the viewpoint of exhibiting high light selective absorption, each independently preferably represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, even more preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

[0022] In the above formula (XI), R 4 represents an alkyl group having 3 to 50 carbon atoms, or an alkyl group having 3 to 50 carbon atoms and at least one methylene group, at least one of the methylene groups being substituted with an oxygen atom.

[0023] R 4 In terms of affinity with hydrophobic substances, solubility in hydrophobic solvents, and production economy, the alkyl group having 3 to 50 carbon atoms preferably has 8 to 45 (e.g., 10 to 45), more preferably 12 to 40, still more preferably 13 to 35, and particularly preferably 14 to 30 carbon atoms. A substituent may be bonded to the carbon atom on the alkyl group.

[0024] R 4 In the above, the alkyl group having 3 to 50 carbon atoms and at least one methylene group preferably has 3 to 40 carbon atoms, more preferably 4 to 35 carbon atoms, and particularly preferably 5 to 30 carbon atoms, from the viewpoints of affinity with hydrophobic substances, solubility in hydrophobic solvents, and production economy. In the alkyl group having 3 to 50 carbon atoms and at least one methylene group, at least one of the methylene groups is substituted with an oxygen atom, and examples thereof include an ethoxy group, a propoxy group, and a 2-methoxyethoxymethyl group. Other examples include polyethylene glycol groups such as a diethylene glycol group and a triethylene glycol group, and polypropylene glycols such as a dipropylene glycol group and a tripropylene glycol group.

[0025] Also, R 4A substituent may be bonded to the carbon atom on the alkyl group. Examples of the substituent include a halogen atom, an alkyl group having 1 to 6 carbon atoms, a cyano group, a nitro group, an alkylsulfinyl group having 1 to 6 carbon atoms, an alkylsulfonyl group having 1 to 6 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, an N-alkylamino group having 1 to 6 carbon atoms, an N,N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfamoyl group having 1 to 6 carbon atoms, and an N,N-dialkylsulfamoyl group having 2 to 12 carbon atoms.

[0026] R 4 When R is an alkyl group having 3 to 50 carbon atoms, in terms of affinity with hydrophobic substances and solubility in hydrophobic solvents, 4 is more preferably an alkyl group having a branched structure and having 3 to 12 carbon atoms, and even more preferably an alkyl group having a branched structure and having 6 to 10 carbon atoms.

[0027] Here, the alkyl group having a branched structure refers to an alkyl group in which at least one of the carbon atoms of the alkyl group is a tertiary carbon or a quaternary carbon. Specific examples of the alkyl group having a branched structure and 3 to 12 carbon atoms include alkyl groups having the following structure: [ka] * indicates a connecting part.

[0028] In the above formula (XI), X 1 represents an electron-withdrawing group. From the viewpoint of improving the light selective absorption, X 1 -NO2, -CN, -COR 8 , -COOR 9 , -OR 10 , halogen atoms (-F, -Cl, -Br, -I), -CSR 11 , -CSOR 12 , or -CSNR 13 is preferred, and a nitro group, a cyano group, or -COOR 9 is more preferred, and a cyano group or -COOR 9More preferably, R 8 , R 9 , R 10 , R 11 , R 12 and R 13 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, for example, 2 to 5 carbon atoms, or a phenyl group.

[0029] In the above formula (XI), Y 1 -CO-, -COO-, -OCO-, -O-, -S-, -NR 5 -, -NR 6 CO-, -CONR 7 From the viewpoint of improving the selective light absorption, R preferably represents -CO-, -COO-, -OCO-, or -O-, and more preferably represents -CO-, -COO-, or -OCO-. 5 , R 6 and R 7 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, for example, 2 to 5 carbon atoms, or a phenyl group.

[0030] In a preferred embodiment of the present invention, the compound (XI) represented by the above formula (XI) is a compound represented by the following formula (XI-I): [ka] From the viewpoint of excellent solubility in various solvents and / or affinity with various compounds, it is preferable that the compound be represented by the following formula:

[0031] In the above formula (XI-I), R 4-1 represents an alkyl group having 1 to 6 carbon atoms, preferably an alkyl group having 2 to 5 carbon atoms, and more preferably an alkyl group having 3 or 4 carbon atoms. n is an integer of 1 to 10, and from the viewpoint of excellent solubility in various solvents and / or affinity with various compounds, preferably an integer of 1 to 8, more preferably an integer of 1 to 6, for example, an integer of 1 to 4, particularly an integer of 1 to 3. When n is within the above range, the light absorption per part by mass is improved, and even if the amount of compound (XI) contained in the members constituting the optical laminate is small, the blue light blocking function can be exhibited. Furthermore, when compound (XI) is contained in a pressure-sensitive adhesive, for example, the pressure-sensitive adhesive function is unlikely to be impaired, and when compound (XI) is contained in a protective film, the optical function of the protective film is unlikely to be impaired. A, R 1 , R 2 and R 3 is the same as in the above formula (XI).

[0032] In a more preferred embodiment of the present invention, the compound represented by the above formula (XI-I) is represented by the following formula (XI-II): [ka] When the compound represented by formula (XI-I) is a compound represented by formula (XI-II), it has excellent solubility in various solvents and / or affinity with various compounds, making it easy to dissolve the compound uniformly in a solvent, and at the same time, it also has excellent affinity with various compounds and exhibits amphiphilicity, so that when the compound is contained in a member constituting an optical laminate, it is less likely to bleed out and can stably exhibit a light-absorbing function.

[0033] In formula (XI-II), R 4-1 and n is the same as in formula (XI-I).

[0034] [Additives] The curable resin composition may contain various fillers as desired for the purposes of adjusting the refractive index, improving the flexural modulus, stabilizing the volume shrinkage rate, and further improving heat resistance, antistatic properties, antiglare properties, etc. The surface treatment layer may also contain additives such as an antioxidant, a light stabilizer, an antistatic agent, a leveling agent, and an antifoaming agent.

[0035] [Formation of coating film] The curable resin composition is usually diluted with a solvent and applied onto the substrate film (21). After application, the solvent is removed by volatilization to form a coating film of the curable resin composition. Examples of the solvent include aromatic solvents such as toluene, xylene, and n-heptane; aliphatic solvents such as cyclohexane, methylcyclohexane, and ethylcyclohexane; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and methyl lactate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; and alcohol solvents such as methanol, ethanol, isopropyl alcohol, and n-propyl alcohol. These solvents may be used alone or in combination.

[0036] [Curing of coating film] The coating film formed on the substrate film (21) in this manner is cured to form an ultraviolet absorbing layer (22). To cure the coating film, a curing treatment appropriate for the curable resin used may be performed. Specifically, if the curable resin used is an ultraviolet curable resin that cures when irradiated with ultraviolet rays, ultraviolet light may be irradiated, and if the curable resin used is an electron beam curable resin that cures when irradiated with electron beams, electron beams may be irradiated. If the curable resin used is a thermosetting resin that cures when heated, the coating film may be heated. The irradiation intensity and irradiation time of the electron beam or ultraviolet light, and the heating temperature and heating time when curing by heating are selected appropriately depending on the curable resin used.

[0037] [Ultraviolet absorbing layer] The thickness of the ultraviolet absorbing layer (22) that can be formed in this manner is usually 1 μm or more, preferably 1.5 μm or more, in terms of having sufficient strength and being able to absorb ultraviolet rays sufficiently, and is usually 10 μm or less, preferably 5 μm or less, in terms of thinning. The thickness of the ultraviolet absorbing layer (22) can be adjusted, for example, by the amount of solvent used for dilution; a larger amount of solvent makes it easier to make the layer thinner. A smaller amount of solvent used makes it easier to make the layer thicker. Furthermore, the thickness can be increased by applying an additional curable resin composition on the coating film obtained by drying.

[0038] [UV absorbing film] The thickness of the ultraviolet absorbing film (2) is the thickness of a single layer film formed from a resin composition containing a thermoplastic resin and an ultraviolet absorber, or is the total thickness of the substrate film (21) and the ultraviolet absorbing layer (22) when the ultraviolet absorbing film (2) is a film having an ultraviolet absorbing layer (22) formed on the surface of the substrate film (21). The thickness of the ultraviolet absorbing film (2) is usually 5 μm or more, preferably 7 μm or more, more preferably 10 μm or more, and usually 200 μm or less, preferably 100 μm or less, more preferably 50 μm or less.

[0039] [Oxygen Barrier Layer] The oxygen barrier layer (3) is a layer that blocks the permeation of oxygen (O2), and its oxygen permeability is usually 60 cm 3 / m 2 24hrs atm or less, preferably 50cm 3 / m 2 ·24hr·atm or less, more preferably 30cm 3 / m 2 24hrs atm or less. From the practical viewpoint of thickness, the lower limit is 0.001 cm 3 / m 2 24hrs atm or more, preferably 0.01cm 3 / m 2 24hrs·atm or more, preferably 0.05cm 3 / m 2The oxygen barrier layer is usually transparent and colorless.

[0040] An example of such an oxygen barrier layer is a polyvinyl alcohol-based resin layer. The polyvinyl alcohol-based resin constituting the polyvinyl alcohol-based resin layer has a degree of saponification of usually 30 or more, preferably 70 or more, more preferably 90 or more, particularly preferably 95 or more, even more preferably 97 or more, and is usually 100 or less, because sufficient oxygen barrier performance can be easily obtained. The thickness of the oxygen barrier layer is usually 0.1 μm or more, preferably 0.5 μm or more, even more preferably 0.7 μm or more, because sufficient oxygen barrier performance can be easily obtained, and from the viewpoints of thinning and economy, it is usually 10 μm or less, preferably 5 μm or less, more preferably 3 μm or less, and especially preferably 1.5 μm or less.

[0041] [Formation of oxygen barrier layer (polyvinyl alcohol-based resin layer)] Such a polyvinyl alcohol-based resin layer can be formed, for example, by applying an aqueous solution of a polyvinyl alcohol-based resin to one side of the ultraviolet-absorbing film (2) and drying it by heating. The content of the polyvinyl alcohol-based resin in the aqueous solution is usually 0.5 to 20 parts, preferably 1 to 10 parts. The heating temperature is, for example, 70 to 100°C, and the heating time is, for example, 1 to 10 minutes.

[0042] When the ultraviolet absorbing film (2) is a resin film, a polyvinyl alcohol resin layer may be formed on one side of the resin film.

[0043] When the ultraviolet absorbing film (2) is a film in which an ultraviolet absorbing layer (22) is formed on one side of a base film (21), the oxygen barrier layer (3) may be formed on the base film (21) side or on the ultraviolet absorbing layer (22) side.

[0044] The polyvinyl alcohol-based resin layer may be formed by applying an aqueous solution of the polyvinyl alcohol-based resin to one side of the vertical polarizing film (4) described below and drying it. It is preferable to subject the vertical polarizing film (4) to a corona treatment in advance, as this can improve adhesion to the polyvinyl alcohol-based resin layer.

[0045] [UV transmittance from UV absorbing film to oxygen barrier layer] The light transmittance (T 380 ) is 10% or less, preferably 8% or less, more preferably 6% or less, particularly preferably 1% or less, and ideally 0 (zero)%. 380 By keeping T at 10% or less, it is possible to suppress the deterioration of polarization performance. 380 indicates the proportion of ultraviolet light (wavelength 380 nm) that is transmitted without being absorbed by the ultraviolet absorbing film (2) and the oxygen barrier layer (3) and reaches the vertical polarizing film (4).

[0046] The light transmittance (T 400 ) is preferably 10% or less, more preferably 5% or less, even more preferably 2% or less, particularly preferably 1% or less, and ideally 0 (zero)%, in order to further suppress deterioration of the polarization performance of the vertical polarizing film (4).

[0047] On the other hand, the light transmittance (T 450 ) is ideally 100% so as not to inhibit blue light emission from the organic EL image display device, but is usually 70% or more, preferably 80% or more, more preferably 85% or more, and particularly preferably 90% or more.

[0048] [Vertical polarizing film] The vertical polarizing plate (1) of the present invention has a vertical polarizing film (4). In the vertical polarizing film (4), the dichroic dye is oriented in the vertical direction, and when an arbitrary direction in the film plane is defined as the x-axis, a direction perpendicular to the x-axis in the film plane is defined as the y-axis, and a film thickness direction perpendicular to the x-axis and y-axis is defined as the z-axis (see FIG. 1), the following formulas (1) to (3) are satisfied: Az>(Ax+Ay) / 2 (1) Ax(z=60°) / Ax>5 (2) Ay(z=60°) / Ay>5 (3) satisfy.

[0049] Here, in formulas (1) to (3), Ax, Ay, Az, Ax(z=60°) and Ay(z=60°) are all absorbances at the absorption maximum wavelength of the dichroic dye in the optical absorption anisotropic film in the vertical polarizing film.

[0050] Ax represents the absorbance of linearly polarized light oscillating in the x-axis direction. Ax can be measured by directing linearly polarized light oscillating in the x-axis direction toward the film surface from the z-axis direction. Ay represents the absorbance of linearly polarized light oscillating in the y-axis direction. Ay can be measured by directing linearly polarized light oscillating in the y-axis direction toward the film surface from the z-axis direction.

[0051] Az represents the absorbance of linearly polarized light oscillating in the z-axis direction. Az can be measured by, for example, directing linearly polarized light oscillating in the z-axis direction toward the side of the film from the xy plane, i.e., when the film is in the xy plane, perpendicular to the side (thickness direction) of the film.

[0052] Ax (z = 60°) represents the absorbance of linearly polarized light oscillating in the x-axis direction when the film is rotated 60° around the y-axis. Ax (z = 60°) can be measured by rotating the film 60° around the y-axis and then incident the same linearly polarized light as that used to measure Ax. Here, the film is rotated by 60° around the y-axis in the state in which Ax was measured, in the direction of incidence of the linearly polarized light.

[0053] Ay(z = 60°) represents the absorbance of linearly polarized light vibrating in the y-axis direction when the film is rotated 60° with the x-axis as the rotation axis. Ay(z = 60°) can be measured by incident linearly polarized light that is the same as the linearly polarized light used to measure Ay in a state where the film is rotated 60° with the x-axis as the rotation axis. Here, the rotation of the film is performed by rotating the film in the state where Ay is measured 60° in the incident direction of linearly polarized light with the x-axis as the rotation axis.

[0054] The absorbance in the z direction in Equation (1) is difficult to measure because the light is incident from the side of the film. Therefore, when the angle formed by the vibration plane of the linearly polarized light, which is the measurement light, and the x - y plane of the film is 90°, the absorbance in the Az direction can be estimated by measuring with the x - y plane of the film tilted 30° and 60° in the incident direction of the linearly polarized light with respect to this vibration plane.

[0055] Specifically, it can be estimated by the following methods and the like. Ax(z = 30°) and Ax(z = 60°) are measured by incident linearly polarized light that is the same as the linearly polarized light used to measure Ax in a state where the film is rotated 30° and 60° with the y-axis as the rotation axis. Similarly, Ay(z = 30) and Ay(z = 60) are measured by incident linearly polarized light that is the same as the linearly polarized light used to measure Ay in a state where the film is rotated 30° and 60° with the x-axis as the rotation axis.

[0056] At this time, if Ax(z = 30°) < Ax(z = 60°) and Ay(z = 30°) = Ay(z = 60°), then Ax(z = 30°) < Ax(z = 60°) < Ax(z = 90°) = Az, and if Ay(z = 30°) < Ay(z = 60°) and Ax(z = 30°) = Ax(z = 60°), then Ay(z = 30°) < Ay(z = 60°) < Ay(z = 90°) = Az. Therefore, Equation (1) is necessarily satisfied.

[0057] Particularly, when there is no absorption anisotropy in the x-y plane, that is, when Ax and Ay are equal, since Ax(z = 30°) = Ay(z = 30°) and Ax(z = 60°) = Ay(z = 60°), Ax(z = 30°) and Ay(z = 30°) can be denoted as A(z = 30°), and Ax(z = 60°) and Ay(z = 60°) can be denoted as A(z = 60°). That is, if A(z = 30°) < A(z = 60°), the relationship A(z = 30°) < A(z = 60°) < A(z = 90°) = Az is satisfied. Further, if A(z = 30°) > (Ax + Ay) / 2, then Az necessarily satisfies Equation (1).

[0058] In the present invention, the vertical polarizing film satisfies the above Equations (2) and (3). Ax(z = 60°) / Ax and Ay(z = 60°) / Ay mean that the larger their numerical values are, the more excellent the light absorption anisotropy is shown. These numerical values may be, for example, 50 or less, 30 or less, 6 or more, or 8 or more. Further, the vertical polarizing film of the present invention preferably satisfies the following Equations (2’) and (3’): Ax(z = 60°) / Ax > 10 (2’) Ay(z = 60°) / Ay > 10 (3’) is satisfied.

[0059] When the vertical polarizing film satisfies Equations (1) to (3), it can be said that the dichroic dye has excellent absorption anisotropy, that is, excellent polarization performance. Due to this excellent property, light from the front direction can be effectively transmitted, and light from an oblique direction can be effectively absorbed.

[0060] In addition, when two or more dichroic dyes with different maximum absorption wavelengths are contained in a vertical polarizing film, Az>(Ax+Ay) / 2, Ax(z=60°) / Ax, and Ay(z=60°) / Ay, which are calculated based on the absorbances Ax, Ay, and Az at the maximum absorption wavelength of at least one of the dichroic dyes contained, should satisfy the relationships of the above formulas (1) to (3). In order to effectively transmit light from the front direction and effectively absorb light from oblique directions, it is preferable that Az>(Ax+Ay) / 2, Ax(z=60°) / Ax, and Ay(z=60°) / Ay, which are calculated based on the absorbances Ax, Ay, and Az at the absorption maximum wavelengths of the dichroic dyes having absorption maximum wavelengths in the wavelength range of 500 to 600 nm, satisfy the relationships of the above formulas (1) to (3).It is also preferable that Az>(Ax+Ay) / 2, Ax(z=60°) / Ax, and Ay(z=60°) / Ay, which are calculated based on the absorbances Ax, Ay, and Az at the absorption maximum wavelengths of the dichroic dyes contained in the vertical polarizing film, satisfy the relationships of the above formulas (1) to (3), respectively.It is particularly preferable to select dichroic dyes so that the above formulas (1) to (3) are satisfied over a wide range, from 350 to 700 nm.

[0061] The thickness of the present vertical polarizing film is preferably 0.1 to 10 μm, more preferably 0.2 to 5 μm, even more preferably 0.2 to 3 μm or 0.5 to 5 μm, and particularly preferably 0.5 to 3 μm. When the thickness of the vertical polarizing film is within the above range, reduction in light absorption in oblique directions is unlikely to occur. In addition, the orientation of the dichroic dye is unlikely to be disturbed, so transmittance in the front direction is likely to be increased.

[0062] [Dichroic dye] The dichroic dye constituting the vertical polarizing film (4) is a dye having a molecule with a long axis direction and a short axis direction, and having different absorbance in the long axis direction and absorbance in the short axis direction. The dichroic dye is not particularly limited as long as it has such properties and can form a vertical polarizing film satisfying the above formulas (1) and (2). The dichroic dye may be a dye or a pigment. The dichroic dye may be a combination of two or more dyes, a combination of two or more pigments, or a combination of a dye and a pigment.

[0063] Examples of such dichroic dyes include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes, and anthraquinone dyes, with azo dyes being preferred. Examples of azo dyes include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes, and stilbene azo dyes, with bisazo dyes and trisazo dyes being preferred. The dichroic dyes may be used alone or in combination of two or more, but it is preferred to use two or more in combination depending on the wavelength range in which light absorption anisotropy is required in the light absorption anisotropic layer.

[0064] When multiple dichroic dyes are combined, it is preferable that at least one of them has a maximum absorption wavelength in the wavelength range of 500 to 600 nm in the optically absorptive anisotropic film. When two dichroic dyes are combined, it is preferable that one of them has a maximum absorption wavelength in the range of 350 to 499 nm or 601 to 750 nm. When three dichroic dyes are combined, it is preferable that one of them has a maximum absorption wavelength in the range of 350 to 499 nm, 500 to 600 nm, and 601 to 750 nm, respectively.

[0065] The azo dye includes a compound represented by formula (I) (hereinafter sometimes referred to as "compound (I)"). K 1 (-N=NK 2 ) p -N=NK 3 (I) [In formula (I), K 1 and K. 3 represent, independently of each other, an optionally substituted phenyl group, an optionally substituted naphthyl group, or an optionally substituted monovalent heterocyclic group. K 2 represents an optionally substituted p-phenylene group, an optionally substituted naphthalene-1,4-diyl group, or an optionally substituted divalent heterocyclic group. p represents an integer of 1 to 4; When p is an integer equal to or greater than 2, multiple K 2 may be the same or different from each other. The —N═N— bond may be replaced with a —C═C—, —COO—, —NHCO—, or —N═CH— bond as long as absorption in the visible region is exhibited.]

[0066] Examples of monovalent heterocyclic groups include groups in which one hydrogen atom has been removed from a heterocyclic compound such as quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole, benzoxazole, etc. Examples of divalent heterocyclic groups include groups in which two hydrogen atoms have been removed from the above heterocyclic compounds.

[0067] K 1 and K. 3 Phenyl, naphthyl and monovalent heterocyclic groups in 2 Examples of the substituent that the p-phenylene group, naphthalene-1,4-diyl group, and divalent heterocyclic group in the formula (I) may optionally have include an alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, or a butoxy group; a fluorinated alkyl group having 1 to 4 carbon atoms, such as a trifluoromethyl group; a cyano group; a nitro group; a halogen atom; and a substituted or unsubstituted amino group, such as an amino group, a diethylamino group, or a pyrrolidino group (a substituted amino group refers to an amino group having one or two alkyl groups having 1 to 6 carbon atoms, or an amino group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms. An unsubstituted amino group is -NH2). ) are mentioned.

[0068] Among the compounds (I), compounds represented by any one of formulas (I-1) to (I-8) are preferred, compounds represented by any one of formulas (I-1) to (I-3) are more preferred, and compounds represented by any one of formulas (I-1) and (I-3) are even more preferred. [ka]

[0069] [In formulas (I-1) to (I-8), B 1 ~B 30 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, a substituted or unsubstituted amino group (the definitions of a substituted amino group and an unsubstituted amino group are as defined above), a chlorine atom, or a trifluoromethyl group. n1 to n4 each independently represent an integer of 0 to 3. If n1 is 2 or more, multiple B 2 may be the same or different from each other, If n2 is 2 or more, multiple B 6 may be the same or different from each other, If n3 is 2 or more, multiple B 9 may be the same or different from each other, If n4 is 2 or more, multiple B 14 may be the same or different.] These dichroic dyes may be used alone or in combination of two or more. It is preferable to use two or more dichroic dyes in combination, as this allows the dyes to exhibit their functions over a wide wavelength range of visible light.

[0070] [Vertical polarizing film] An example of the vertical polarizing film (4) is one in which a matrix is ​​formed by polymerizing and curing a polymerizable liquid crystal compound in a state where the polymerizable liquid crystal compound is oriented in the vertical direction, and the dichroic dye is oriented in the vertical direction within this matrix.

[0071] The content of the dichroic dye in the vertical polarizing film is selected depending on the desired function, but from the viewpoint of obtaining good light absorption characteristics, the content of the dichroic dye (the total amount when two or more types are included) is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, even more preferably 0.1 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the solid content of the liquid crystal composition. A dichroic dye content within this range is preferable because it is less likely to disrupt the liquid crystal alignment of the liquid crystal compound.

[0072] [Polymerizable liquid crystal compound] The polymerizable liquid crystal compound contained in the composition for forming the light absorption anisotropic layer is used to align the dichroic dye through host-guest interaction. The polymerizable liquid crystal compound has one or more polymerizable groups in the molecule and has liquid crystal properties.

[0073] The polymerizable group refers to a group that participates in a polymerization reaction, and is preferably a photopolymerizable group. Here, the photopolymerizable group refers to a group that can participate in a polymerization reaction by an active radical or acid generated from a photopolymerization initiator, as described below. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, an oxiranyl group, and an oxetanyl group. Among these, a (meth)acryloyl group, a (meth)acryloyloxy group, a vinyloxy group, an oxiranyl group, and an oxetanyl group are preferred, with a (meth)acryloyl group and a (meth)acryloyloxy group being more preferred. The liquid crystal property may be either a thermotropic liquid crystal or a lyotropic liquid crystal, but when mixed with the above-mentioned dichroic dye, a thermotropic liquid crystal is preferred. In this specification, (meth)acryloyl refers to at least one of acryloyl and methacryloyl. The same applies to notations such as (meth)acrylic.

[0074] When a polymer of a polymerizable liquid crystal compound is formed by a polymerization reaction and a film containing the polymer and a dichroic dye exhibits optical absorption anisotropy, the liquid crystal state exhibited by the polymerizable liquid crystal compound is a smectic phase, and preferably a higher-order smectic phase, from the viewpoint of high performance. Among these, higher-order smectic polymerizable liquid crystal compounds that form a smectic B phase, a smectic D phase, a smectic E phase, a smectic F phase, a smectic G phase, a smectic H phase, a smectic I phase, a smectic J phase, a smectic K phase, or a smectic L phase are more preferred, and higher-order smectic polymerizable liquid crystal compounds that form a smectic B phase, a smectic F phase, or a smectic I phase are even more preferred. When the liquid crystal phase formed by the polymerizable liquid crystal compound is one of these higher-order smectic phases, an optical absorption anisotropy layer with higher optical absorption anisotropy can be produced. Such an optically absorptive anisotropic layer exhibits high optical absorption anisotropy properties, and Bragg peaks derived from higher-order structures such as hexatic and crystalline phases are obtained in X-ray diffraction measurements. The Bragg peaks are peaks derived from the periodic structure of molecular orientation, and the optically absorptive anisotropic layer can have a periodic spacing of 3 to 6 Å. The optically absorptive anisotropic layer preferably contains a polymer of a polymerizable liquid crystal compound oriented in a smectic phase, from the viewpoint of obtaining higher optical absorption anisotropy properties.

[0075] The polymerizable liquid crystal compound may be a monomer, an oligomer in which a polymerizable group is polymerized, or a polymer. As such a polymerizable liquid crystal compound, known compounds can be used, such as those described in JP-A-2020-76920 and JP-A-6728581.

[0076] The polymerizable liquid crystal compound forming the vertical polarizing film preferably has a maximum absorption wavelength between 300 and 400 nm. When a photopolymerization initiator is included in the polymerizable liquid crystal composition, the polymerization reaction and gelation of the polymerizable liquid crystal compound may progress during long-term storage. However, if the polymerizable liquid crystal compound has a maximum absorption wavelength between 300 and 400 nm, even if the composition is exposed to ultraviolet light during storage, the generation of reactive species from the photopolymerization initiator and the progression of the polymerization reaction and gelation of the polymerizable liquid crystal compound due to the reactive species can be effectively suppressed. This is advantageous in terms of long-term stability of compositions containing the polymerizable liquid crystal compound, and can improve the alignment and film thickness uniformity of the resulting cured liquid crystal film. The maximum absorption wavelength of the polymerizable liquid crystal compound can be measured using a UV-visible spectrophotometer in a solvent. The solvent can dissolve the polymerizable liquid crystal compound, such as chloroform.

[0077] From the viewpoint of enhancing the alignment of the polymerizable liquid crystal compound, the content of the polymerizable liquid crystal compound in the liquid crystal composition for forming the vertical polarizing film is preferably 70 parts by mass or more, more preferably 80 parts by mass or more, and preferably 99.5 parts by mass or less, more preferably 99 parts by mass or less, even more preferably 94 parts by mass or less, and still more preferably 90 parts by mass or less, relative to 100 parts by mass of the resulting vertical polarizing film. The content of the liquid crystal compound can be calculated as the ratio of the liquid crystal compound to 100 parts by mass of the solid content of the liquid crystal composition for forming the vertical polarizing film.

[0078] In a vertical polarizing film containing a dichroic dye and a liquid crystal compound, the dichroic dye is preferably encapsulated in a polymerizable liquid crystal compound, and the dichroic dye and the polymerizable liquid crystal compound are preferably oriented with a high degree of order in the vertical direction of the vertical polarizing film. Since the polymerizable liquid crystal compound and the dichroic dye are oriented with a high degree of order, when a laminate including the vertical polarizing film is incorporated into an organic EL display device, the laminate tends to have excellent transmittance in the front direction and reduced directional anisotropy of light absorption characteristics in oblique directions, thereby providing an excellent effect of preventing peeping from oblique directions.

[0079] In the present invention, the liquid crystal composition used to form the vertical polarizing film may contain components other than the dichroic dye and the liquid crystal compound. Examples of such components include a polymerization initiator, a leveling agent, a solvent, an antioxidant, and a photosensitizer. These components may be used alone or in combination of two or more.

[0080] To ensure good alignment of the dichroic dye, the content of the dichroic dye in the vertical polarizing film is preferably from 0.1 to 30 parts by mass, more preferably from 0.1 to 20 parts by mass, even more preferably from 0.1 to 10 parts by mass, and particularly preferably from 0.1 to 5 parts by mass, relative to 100 parts by mass of the vertical polarizing film. A dichroic dye content within this range is preferred because it is less likely to disrupt the liquid crystal alignment of the polymerizable liquid crystal compound when the vertical polarizing film is formed.

[0081] The vertical polarizing film is, for example, a mixing step of mixing a polymerizable liquid crystal compound, a dichroic dye, and optionally an additive such as a solvent at a predetermined temperature and stirring the mixture to obtain a liquid crystal composition; a coating step of forming a coating film of the obtained liquid crystal composition on a substrate; a drying step of drying the formed coating film and simultaneously causing phase transition of the polymerizable liquid crystal compound to form a dried coating film; A curing process in which the polymerizable liquid crystal compound in the dried coating film is polymerized and cured while maintaining its liquid crystal orientation. It can be produced by a method comprising:

[0082] [Mixing process] The mixing step is a step of mixing a polymerizable liquid crystal compound and a dichroic dye together, and when mixing these, a polymerization initiator, a solvent, and other additives may be mixed together.

[0083] [Polymerization initiator] The polymerization initiator mixed with the polymerizable liquid crystal compound and the dichroic dye in the mixing step is a compound capable of initiating the polymerization reaction of the polymerizable liquid crystal compound. As the polymerization initiator, a photopolymerization initiator that generates active radicals by the action of active energy rays, particularly light, is preferred.

[0084] Examples of such polymerization initiators include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, and sulfonium salts.

[0085] Examples of the benzophenone compound include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, and 2,4,6-trimethylbenzophenone.

[0086] Examples of alkylphenone compounds include diethoxyacetophenone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethan-1-one, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propan-1-one, 1-hydroxycyclohexyl phenyl ketone, and oligomers of 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propan-1-one.

[0087] Examples of the acylphosphine oxide compound include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0088] Examples of the triazine compound include 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, and 2,4-bis(trichloromethyl)-6-[2-(5-methylfuran-2-yl)ethenyl]-1,3,5-triazine. )-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(4-diethylamino-2-methylphenyl)ethenyl]-1,3,5-triazine, and 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3,5-triazine.

[0089] The polymerization initiator may be commercially available. Examples of commercially available polymerization initiators include Irgacure (registered trademark) 907, 184, 651, 819, 250, and 369 (BASF); Seikuol (registered trademark) BZ, Z, and BEE (Seiko Chemical Co., Ltd.); Kayacure (registered trademark) BP100 and UVI-6992 (Nippon Kayaku Co., Ltd.); Adeka Optomer SP-152 and SP-170 (ADEKA Corporation); TAZ-A and TAZ-PP (DKSH Japan Co., Ltd.); and TAZ-104 (Sanwa Chemical Co., Ltd.).

[0090] The content of the polymerization initiator is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, relative to 100 parts by mass of the polymerizable liquid crystal compound, from the viewpoint of initiating polymerization, and is preferably 30 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 8 parts by mass or less, from the viewpoint of preventing the alignment of the polymerizable liquid crystal compound from being disturbed.

[0091] 〔solvent〕 The solvent to be mixed with the polymerizable liquid crystal compound and the dichroic dye in the mixing step is preferably one that can completely dissolve the liquid crystal compound, and when the liquid crystal compound is a polymerizable liquid crystal compound, it is also preferably a solvent that is inert to the polymerization reaction.

[0092] Examples of the solvent include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; Aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile, ether solvents such as tetrahydrofuran and dimethoxyethane; Examples of the solvent include chlorine-containing solvents such as chloroform and chlorobenzene. These solvents may be used alone or in combination of two or more.

[0093] The content of the solvent in the liquid crystal composition is preferably 50 to 98% by mass relative to the total amount of the liquid crystal composition, i.e., the proportion of the solid content of the liquid crystal composition that will become the vertical polarizing film is preferably 2 to 50% by mass relative to the total amount of the liquid crystal composition. When the solid content is 50% by mass or less relative to the total amount of the liquid crystal composition, the viscosity of the liquid crystal composition is low, making it easier to make the thickness of the obtained vertical polarizing film uniform and reducing the tendency for unevenness to occur. The content of the solid content in the liquid crystal composition can be determined depending on the desired thickness of the vertical polarizing film, and a higher solid content makes it easier to form a thicker vertical polarizing film.

[0094] [Antioxidants] In the mixing step, an antioxidant may be mixed with the polymerizable liquid crystal compound and the dichroic dye. By adding an antioxidant, the polymerization reaction of the polymerizable liquid crystal compound can be controlled. The antioxidant may be a primary antioxidant selected from phenol-based antioxidants, amine-based antioxidants, quinone-based antioxidants, and nitroso-based antioxidants, or a secondary antioxidant selected from phosphorus-based antioxidants and sulfur-based antioxidants.

[0095] In order to polymerize the polymerizable liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound, the content of the antioxidant is usually 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the polymerizable liquid crystal compound. The antioxidants can be used alone or in combination of two or more kinds.

[0096] [Photosensitizer] In the mixing step, a photosensitizer may be mixed with the polymerizable liquid crystal compound and the dichroic dye. The use of a photosensitizer can increase the sensitivity of the photopolymerization initiator, allowing the polymerizable liquid crystal compound to be polymerized with a small amount of light. Examples of photosensitizers include xanthones such as xanthone and thioxanthone; anthracenes having substituents such as anthracene and alkyl ether; phenothiazine; and rubrene. The photosensitizers can be used alone or in combination of two or more. The content of the photosensitizer is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the polymerizable liquid crystal compound.

[0097] The vertical polarizing plate (1) of the present invention comprises such an ultraviolet absorbing film (2), an oxygen barrier layer (3), and a vertical polarizing film (4) laminated in this order (FIG. 1).

[0098] The ultraviolet absorbing film (2) and the oxygen barrier layer (3) may be laminated directly or via an adhesive layer (not shown). The adhesive layer is a pressure-sensitive adhesive layer or an adhesive layer. The adhesive layer is usually colorless and transparent, and is isotropic, exhibiting no retardation in the in-plane direction or in the thickness direction.

[0099] [Adhesive layer] The pressure-sensitive adhesive layer is a layer of a pressure-sensitive adhesive. The pressure-sensitive adhesive usually contains a polymer. Examples of the polymer include an acrylic polymer, a silicone polymer, a polyester, a polyurethane, and a polyether. Among these, an acrylic pressure-sensitive adhesive containing an acrylic polymer is preferred because it is colorless, has excellent optical transparency, has appropriate wettability and cohesive strength, has excellent adhesiveness, and further has high weather resistance and heat resistance, and is less likely to lift or peel under conditions of heating or humidity.

[0100] As the acrylic polymer, a copolymer of a (meth)acrylate in which the alkyl group in the ester moiety is an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, or a butyl group, and a (meth)acrylic monomer having a functional group, such as (meth)acrylic acid or hydroxyethyl (meth)acrylate, is preferred.

[0101] A pressure-sensitive adhesive containing such a copolymer is preferable because it has excellent adhesiveness and can be removed relatively easily after being attached to a transfer-receiving object without leaving any adhesive residue on the transfer-receiving object. The glass transition temperature of the acrylic polymer is preferably 25°C or lower, more preferably 0°C or lower. The mass-average molecular weight of such an acrylic polymer is preferably 100,000 or higher.

[0102] The pressure-sensitive adhesive layer may contain an ultraviolet absorber. By containing an ultraviolet absorber, in addition to the ultraviolet absorption effect of the ultraviolet absorbing film (2), it becomes easy to set the light transmittance at a wavelength of 380 nm from the ultraviolet absorbing film (2) to the oxygen barrier layer (3) within the range of the present invention (10% or less).

[0103] The adhesive may contain a light diffusing agent. The light diffusing agent is an additive that imparts light diffusing properties to the adhesive, and may be fine particles having a refractive index different from that of the polymer contained in the adhesive. Examples of light diffusing agents include fine particles made of inorganic compounds and fine particles made of organic compounds (polymers). Since many of the polymers contained as active ingredients in adhesives, including acrylic polymers, have a refractive index of approximately 1.4 to 1.6, it is preferable to appropriately select a light diffusing agent from those having a refractive index of 1.2 to 1.8. The difference in refractive index between the polymer contained as an active ingredient in the adhesive and the light diffusing agent is usually 0.01 or more, and from the perspective of the brightness and display performance of the display device, a difference of 0.01 to 0.2 is preferable. The fine particles used as the light diffusing agent are preferably spherical fine particles, and more preferably nearly monodisperse fine particles, with an average particle size of 2 to 6 μm being more preferable. The refractive index is measured using a common minimum deviation method or an Abbe refractometer.

[0104] Examples of inorganic compound particles include aluminum oxide (refractive index 1.76) and silicon oxide (refractive index 1.45). Examples of organic compound (polymer) particles include melamine beads (refractive index 1.57), polymethyl methacrylate beads (refractive index 1.49), methyl methacrylate / styrene copolymer resin beads (refractive index 1.50-1.59), polycarbonate beads (refractive index 1.55), polyethylene beads (refractive index 1.53), polystyrene beads (refractive index 1.6), polyvinyl chloride beads (refractive index 1.46), and silicone resin beads (refractive index 1.46). The content of the light diffusing agent is typically 3-30 parts by mass per 100 parts by mass of the polymer.

[0105] The thickness of the adhesive is not particularly limited as it is determined depending on the adhesive strength, etc., but is usually 1 μm to 40 μm. From the viewpoints of processability and durability, the thickness is preferably 3 μm to 25 μm, more preferably 5 μm to 20 μm. By making the thickness of the adhesive layer formed from the adhesive 5 μm to 20 μm, it is possible to maintain brightness when the display device is viewed from the front, and to make it difficult for bleeding or blurring of the displayed image to occur.

[0106] When the ultraviolet absorbing film (2) and the oxygen barrier layer (3) are laminated via a pressure-sensitive adhesive layer, the adhesion between the pressure-sensitive adhesive layer and the ultraviolet absorbing film (2) and the adhesion between the pressure-sensitive adhesive layer and the oxygen barrier layer (3) are usually 0.3 N / 25 mm or more, and the adhesion may be so strong that it causes destruction (material destruction) of the ultraviolet absorbing film (2), the pressure-sensitive adhesive layer, and the oxygen barrier layer (3).

[0107] [Adhesive layer] The adhesive layer is a layer formed by hardening an adhesive, such as a dry-to-solidify adhesive.

[0108] Dry-setting adhesives are solvent-containing adhesives that dry and solidify to form an adhesive layer and exhibit adhesive strength. Examples of such dry-setting adhesives include polymers of monomers having a protic functional group such as a hydroxyl group, a carboxyl group, or an amino group and an ethylenically unsaturated group; compositions containing a urethane resin as the main component and a crosslinking agent such as a polyaldehyde, an epoxy compound, an epoxy resin, a melamine compound, a zirconia compound, or a zinc compound; and compositions containing a curable compound. Examples of polymers of monomers having a protic functional group and an ethylenically unsaturated group include ethylene-maleic acid copolymers, itaconic acid copolymers, acrylic acid copolymers, acrylamide copolymers, saponified polyvinyl acetate, and polyvinyl alcohol-based resins.

[0109] Examples of polyvinyl alcohol-based resins include polyvinyl alcohol, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol, methylol group-modified polyvinyl alcohol, and amino group-modified polyvinyl alcohol. When an adhesive contains a polyvinyl alcohol-based resin, the adhesive usually contains water. The content of the polyvinyl alcohol-based resin in such an adhesive is usually 1 to 10 parts by mass, and preferably 1 to 5 parts by mass, per 100 parts by mass of water.

[0110] Examples of urethane resins include polyester ionomer urethane resins. The polyester ionomer urethane resin referred to here is a urethane resin having a polyester skeleton, into which a small amount of an ionic component (hydrophilic component) has been introduced. Such ionomer urethane resins can be emulsified in water to form emulsions without the use of an emulsifier, and can therefore be used as water-based pressure-sensitive adhesives. When using a polyester ionomer urethane resin, it is effective to incorporate a water-soluble epoxy compound as a crosslinking agent.

[0111] Examples of epoxy resins include polyamide epoxy resins obtained by reacting epichlorohydrin with polyamide polyamines obtained by reacting polyalkylene polyamines such as diethylenetriamine or triethylenetetramine with dicarboxylic acids such as adipic acid. Commercially available polyamide epoxy resins include "Sumirez Resin (registered trademark) 650" and "Sumirez Resin 675" (both manufactured by Sumika Chemtex Co., Ltd.) and "WS-525" (manufactured by Nippon PMC Corporation). When an epoxy resin is added, the amount added is typically 1 to 100 parts by mass, preferably 1 to 50 parts by mass, per 100 parts by mass of the polyvinyl alcohol-based resin.

[0112] The thickness of the adhesive layer formed from the dry-to-set adhesive is usually 0.001 to 5 μm, preferably 0.01 to 2 μm, and more preferably 0.01 to 0.5 μm. If the adhesive layer formed from the dry-to-set adhesive is too thick, it is likely to result in poor appearance.

[0113] The adhesive also includes an active energy ray-curable adhesive. The active energy ray-curable adhesive is an adhesive that cures when irradiated with active energy rays. Examples of the active energy ray-curable adhesive include a cationically polymerizable adhesive containing an epoxy compound and a cationic polymerization initiator, a radically polymerizable adhesive containing an acrylic curing component and a radical polymerization initiator, an adhesive containing both a cationically polymerizable curing component such as an epoxy compound and a radically polymerizable curing component such as an acrylic compound, and further containing a cationic polymerization initiator and a radical polymerization initiator, and an adhesive that does not contain these polymerization initiators and is cured by irradiation with an electron beam.

[0114] Among these, radically polymerizable active energy ray-curable adhesives containing an acrylic curing component and a photoradical polymerization initiator, and cationic polymerizable active energy ray-curable adhesives containing an epoxy compound and a photocationic polymerization initiator are preferred. Examples of acrylic curing components include (meth)acrylates such as methyl (meth)acrylate and hydroxyethyl (meth)acrylate, and (meth)acrylic acid. Active energy ray-curable adhesives containing epoxy compounds may further contain compounds other than epoxy compounds. Examples of compounds other than epoxy compounds include oxetane compounds and acrylic compounds.

[0115] Examples of the photoradical polymerization initiator and photocationic polymerization initiator include the above-mentioned photoradical polymerization initiator and photocationic polymerization initiator. The content of the radical polymerization initiator and the cationic polymerization initiator is usually 0.5 to 20 parts by mass, and preferably 1 to 15 parts by mass, per 100 parts by mass of the active energy ray-curable adhesive.

[0116] The active energy ray-curable adhesive may further contain an ion trapping agent, an antioxidant, a chain transfer agent, a tackifier, a thermoplastic resin, a filler, a flow adjuster, a plasticizer, an antifoaming agent, and the like.

[0117] Examples of active energy rays include visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, γ-rays, and electron beams, with ultraviolet light and electron beams being preferred.

[0118] The adhesive layer may contain an ultraviolet absorber. By containing an ultraviolet absorber, in addition to the ultraviolet absorption effect of the ultraviolet absorbing film (2), it becomes easy to set the light transmittance at a wavelength of 380 nm from the ultraviolet absorbing film (2) to the oxygen barrier layer (3) within the range of the present invention (10% or less).

[0119] When the ultraviolet absorbing film (2) and the oxygen barrier layer (3) are laminated via an adhesive layer, the adhesion strength between the adhesive layer and the ultraviolet absorbing film (2) and between the adhesive layer and the oxygen barrier layer (3) is usually 0.01 N / 25 mm or more, and the adhesion strength may be so strong that it causes destruction (material destruction) of the ultraviolet absorbing film (2), adhesive layer, and oxygen barrier layer (3).

[0120] To directly laminate the ultraviolet absorbing film (2) and the oxygen barrier layer (3), for example, an aqueous solution of a polyvinyl alcohol resin may be applied to one surface of the ultraviolet absorbing film (2) and dried by heating to form the oxygen barrier layer (3). To laminate the ultraviolet absorbing film (2) and the oxygen barrier layer (3) via a pressure-sensitive adhesive layer, for example, the oxygen barrier layer (3) may be formed on the vertical polarizing film (4) in advance, a pressure-sensitive adhesive layer may be laminated on the oxygen barrier layer (3) formed on the vertical polarizing film (4), and then the ultraviolet absorbing film (2) may be laminated thereon.

[0121] To laminate the ultraviolet-absorbing film (2) and the oxygen barrier layer (3) via an adhesive layer, for example, an uncured adhesive composition may be applied to the ultraviolet-absorbing film (2) to form a coating film, the oxygen barrier layer (3) may be laminated on top of this coating film, and then this coating film may be cured. Alternatively, an uncured adhesive composition may be applied to the oxygen barrier layer (3) to form a coating film, the ultraviolet-absorbing film (2) may be laminated on top of this coating film, and then this coating film may be cured. To cure the coating film, a method appropriate for the adhesive composition used may be used. For example, when an active energy ray-curable adhesive composition that is cured by active energy rays is used as the adhesive composition, active energy rays appropriate for the composition may be irradiated.

[0122] As shown in Fig. 2, a linear polarizer (5) may be laminated on the side of the vertical polarizing film (4) of the vertical polarizer (1) of the present invention opposite the oxygen barrier layer to form a composite linear polarizer (11). If the linear polarizer (5) constituting this composite linear polarizer (11) includes a polyvinyl alcohol polarizer in which a dichroic dye is oriented in a polyvinyl alcohol resin film, the oxygen barrier layer (4) is laminated on one side of the vertical polarizing film (4) and the polyvinyl alcohol polarizer is laminated on the other side, which further suppresses decomposition of the dichroic dye in the vertical polarizing film (4) and further suppresses migration of the dichroic dye, thereby further suppressing deterioration in the polarization performance of the vertical polarizing film, which is preferable.

[0123] The polyvinyl alcohol polarizer may be obtained by uniaxially stretching a polyvinyl alcohol-based resin film, dyeing it with a dichroic dye, and generally treating it with an aqueous boric acid solution. The dichroic dye may be, for example, iodine.

[0124] The linear polarizing plate (5) may be a polyvinyl alcohol polarizer alone, or may be a polyvinyl alcohol polarizer with a polarizer protective film laminated on one or both sides. Examples of polarizer protective films include cellulose-based resin films, cycloolefin-based resin films, and acrylic resin films. The polyvinyl alcohol polarizer and the polarizer protective film are usually laminated via an adhesive layer. Examples of adhesives include the above-mentioned dry-solidifying adhesives and active energy ray-curable adhesives.

[0125] As shown in Fig. 3, a circular polarizer (12) may be formed by laminating a retardation plate (6) on the side of the linear polarizer (5) of the composite linear polarizer (11) opposite the vertical polarizer. In this circular polarizer (12), the retardation plate (6) is a retardation plate that functions as a λ / 4 plate for light incident from the front. Specifically, the in-plane retardation measured with light incident from the front is such that the in-plane retardation value Re(550) at a wavelength λ of 550 nm is 130 nm to 150 nm, and the in-plane retardation value Re(450) at a wavelength λ of 450 nm is 110 nm to 130 nm. Furthermore, the angle between the slow axis measured with light incident from the front and the absorption axis of the linear polarizer (5) is ideally 45°, but is usually 30° to 60°, and preferably 40° to 50°.

[0126] Examples of the retardation plate (6) include a retardation film that can be obtained by, for example, stretching a thermoplastic resin film, etc. Other examples include a retardation film that is a single cured layer made of a polymer of a polymerizable liquid crystal compound, and a retardation film that is composed of two layers: such a cured layer and an alignment layer for aligning the polymerizable liquid phase compound when the cured layer is formed.

[0127] Examples of the retardation film include those exemplified as "horizontally aligned retardation film i" in paragraphs 0172 to 0187 of JP-A No. 2022-176121.

[0128] Examples of the retardation film include those listed as "horizontally aligned retardation film ii" in paragraphs 0189 to 0204 of JP-A No. 2022-176121. The retardation plate may be such a retardation film alone, or may be a retardation film alone. The retardation plate may be formed by laminating a retardation film and a retardation film. The retardation plate may be formed by laminating two or more retardation films.

[0129] The circularly polarizing plate (12) is placed on the viewing side of the image display element to form an image display element (such as an organic EL display element). The circularly polarizing plate (12) can be attached to the image display element using an adhesive layer.

[0130] The image display device can be used as mobile devices such as smartphones and tablets, televisions, digital photo frames, electronic signs, measuring instruments or meters, office equipment, medical equipment, computing equipment, and the like.

[0131] The dichroic dye contained in the vertical polarizing film (4) constituting the vertical polarizing plate (1) of the present invention is prone to decomposition when exposed to ultraviolet light in the presence of oxygen (O2). In the vertical polarizing plate (1) of the present invention, the ultraviolet absorbing film (2) and the oxygen barrier layer (3) are laminated on the vertical polarizing film (4), which is thought to suppress decomposition of the dichroic dye and thereby suppress deterioration of the polarization performance even when exposed to sunlight in the outdoor atmosphere. [Example]

[0132] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0133] Example 1 [Preparation of Composition A for Forming Alignment Film] Composition A for forming an alignment film was prepared by dissolving 0.3 parts by weight of an alignment polymer [Sunever SE-610 manufactured by Nissan Chemical Industries, Ltd. (solid content concentration 1.0 wt%)] in 27.7 parts by weight of propylene glycol monomethyl ether. Composition A for forming an alignment film is a composition for forming alignment film A used to form a vertical polarizing film.

[0134] [Preparation of Liquid Crystal Composition A] Liquid crystal composition A is Polymerizable liquid crystal compound 1: [ka] 75 parts by weight, Polymerizable liquid crystal compound 2: [ka] 25 parts by weight, Dichroic dye 1: [ka] 2.8 parts by weight, Dichroic dye 2: [ka] 2.8 parts by weight, Dichroic dye 3: [ka] 2.8 parts by weight, 6 parts by weight of a polymerization initiator (Ciba Specialty Chemicals' "Irgacure 369" (2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one)); 0.3 parts by weight of leveling agent (BYK-Chemie's "BYK-361N" (polyacrylate compound)) The liquid crystal composition A was prepared by dissolving it in 250 parts by weight of a solvent (o-xylene). Note that the liquid crystal composition A is a composition for forming a vertical polarizing film.

[0135] [Preparation of Protective Layer] After corona treatment was performed on the release-treated surface of a release-treated polyethylene terephthalate film (SP-PLR382050 manufactured by Lintec Corporation) (release film), the following protective layer-forming composition was applied by bar coating (#2 30 mm / s) and dried by heating in a drying oven set at 80°C for 1 minute to obtain a dried coating. Next, using a UV irradiation device (Uniquer VB-15201BY-A manufactured by Ushio Inc.), ultraviolet light was irradiated onto the coating layer of the protective layer-forming composition (under a nitrogen atmosphere, cumulative light intensity at a wavelength of 365 nm: 500 mJ / cm). 2 ) to obtain a release film with a protective layer formed on the surface of the release film. The thickness of the obtained protective layer was measured using an ellipsometer M-220 (manufactured by JASCO Corporation) and was found to be 1.5 μm.

[0136] <Preparation of protective layer-forming composition> The following components were mixed and stirred at 50° C. for 4 hours to obtain a composition for forming a protective layer. Acrylate monomers: [ka] (A-1) 70 copies Urethane acrylate resin: EBECRYL 4858 (manufactured by Daicel Allnex Co., Ltd.) 30 parts Polymerization initiator: Omnirad 907 (IGM Resins BV) 3 copies ·solvent: Methyl ethyl ketone 10 parts

[0137] [Formation of Alignment Film A] The protective layer of the polyethylene terephthalate film was subjected to corona treatment, and the composition A for forming an alignment film obtained above was applied using a bar coater.The film was then dried by placing it in an oven heated to 120°C for 1 minute to form alignment film A.

[0138] [Formation of vertical polarizing film] The liquid crystal composition A obtained above was applied onto the alignment film A formed above using a bar coater, heated to 100°C for 60 seconds, then naturally cooled. The applied liquid crystal composition A was irradiated with ultraviolet light under a nitrogen atmosphere using a high-pressure mercury lamp ("Uniqure VB-15201BY-A" manufactured by Ushio Inc.). This cured film A was formed by curing the applied liquid crystal composition A on the alignment film A formed on the protective layer of the polyethylene terephthalate film, thereby forming a vertical polarizing film (cured film A / alignment film A). This vertical polarizing film was formed on the protective layer of the polyethylene terephthalate film and had a two-layer structure consisting of the alignment film A and the cured film A from the protective layer side of the polyethylene terephthalate film. The ultraviolet light was irradiated from the side where the liquid crystal composition A was applied. The ultraviolet light had an integrated light intensity of 1000 mJ / cm at a wavelength of 365 nm. 2 The irradiation was carried out so that

[0139] [Three-dimensional absorbance measurement] The absorbance of the vertical polarizing film was measured as follows. Using a spectrophotometer (Shimadzu UV-3150) equipped with a prism polarizer folder, we measured three-dimensional absorbance at the wavelength of maximum absorption using the double-beam method over the wavelength range of 380–680 nm in 2 nm steps. Here, three-dimensional absorbance refers to the absorbance (Ax, Ay, Az) in each direction relative to linearly polarized light, where the x-axis is any direction within the film plane, the y-axis is the direction perpendicular to the x-axis within the film plane, and the z-axis is the thickness direction of the film. Specifically, measurements were performed by rotating the sample relative to the linearly polarized light used as the measurement light. Furthermore, absorbance in the z-direction is difficult to measure because, by definition, light is incident from the side of the sample. Therefore, we estimated the absorbance in the Az direction by tilting the x-y plane of the sample 60° relative to the plane of vibration of the linearly polarized light used as the measurement light.

[0140] Specifically, Ax(z=60°) was measured by rotating the sample 60° so that it included the y-axis and then incidenting the same linearly polarized light as when Ax was measured. Similarly, Ay(z=60°) was measured by rotating the sample 60° so that it included the x-axis and then incidenting the same linearly polarized light as when Ay was measured.

[0141] In the case where there is no absorption anisotropy in the x-y plane, that is, when Ax and Ay are equal, since Ax(z = 60°) = Ay(z = 60°), Ax(z = 60°) and Ay(z = 60°) are denoted as A(z = 60°).

[0142] The vertically polarized film satisfies the relationship of A(z = 60°) < A(z = 90°) = Az. Furthermore, if A(z = 60) > (Ax + Ay) / 2, then inevitably the following formula (1) is satisfied. Az > (Ax + Ay) / 2 (1) As a result of measuring the three-dimensional absorbance of the vertically polarized film, maximum absorptions derived from three kinds of dyes were obtained.

[0143] First absorption: The three-dimensional absorbance at a wavelength of 400 nm was Ax = 0.115, Ay = 0.115, and A(z = 60°) = 0.692. That is, the vertically polarized film satisfies formulas (1), (2), and (3) as follows. Az > A(z = 60°) > (Ax + Ay) / 2 (1) Ax(z = 60°) / Ax = 6.0 > 5 (2) Ay(z = 60°) / Ay = 6.0 > 5 (3)

[0144] Second absorption: The three-dimensional absorbance at a wavelength of 526 nm was Ax = 0.062, Ay = 0.062, and A(z = 60) = 0.639. That is, the vertically polarized film satisfies formulas (1), (2), and (3) as follows. Az > A(z = 60°) > (Ax + Ay) / 2 (1) Ax(z = 60°) / Ax = 10.2 > 5 (2) Ay(z = 60°) / Ay = 10.2 > 5 (3)

[0145] Third absorption: The three-dimensional absorbance at a wavelength of 622 nm was Ax = 0.049, Ay = 0.049, and A(z = 60) = 0.468.

[0146] That is, the vertical polarizing film satisfies the following formulas (1), (2), and (3). Az>A(z=60°)> (Ax+Ay) / 2 (1) Ax(z=60°) / Ax = 11.3 > 5 (2) Ay(z=60°) / Ay = 11.3 > 5 (3)

[0147] [Film thickness measurement] The thickness of the cured film A (liquid crystal cured film) in the vertical polarizing film was measured using a laser microscope (LEXT, manufactured by Olympus Corporation) and was found to be 2.3 μm.

[0148] [Preparation of oxygen barrier layer (A)] 3.8 parts by mass of polyvinyl alcohol ("Z210" manufactured by Mitsubishi Chemical Corporation) was dissolved in 100 parts by mass of pure water and mixed to prepare a curable composition (1) for forming an oxygen barrier layer.

[0149] The exposed surface (cured film A side) of the vertical polarizing film (cured film A / alignment film A) formed on one side of the protective layer of the polyethylene terephthalate film was subjected to corona treatment, and the curable composition for forming an oxygen barrier layer (1) obtained above was applied using a bar coater and then dried at 100°C for 1.5 minutes to form an oxygen barrier layer (A) on the vertical polarizing film, thereby obtaining a vertical polarizing film (1) with an oxygen barrier layer. The curable composition for forming an oxygen barrier layer (1) was applied while adjusting the thickness of the oxygen barrier layer (A) to 0.1 μm. The thickness of the obtained oxygen barrier layer (A) was 0.1 μm. The obtained vertical polarizing film (1) with an oxygen barrier layer had a layer structure of oxygen barrier layer (A) / vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film.

[0150] [Preparation of UV-absorbing film (A)] A cycloolefin resin film (COP film) ("ZEONORFILM G+" manufactured by ZEON Corporation) was prepared as the ultraviolet absorbing film (A). This ultraviolet absorbing film (A) had a thickness of 13 μm and a light transmittance T 380 is 5%, and the transmittance T 400 is 84%, and the light transmittance T 450 The transparency was 90%, and the film was colorless and transparent to the naked eye. The ultraviolet absorbing film (A) had an in-plane retardation of 1.7 nm at a wavelength of 550 nm.

[0151] [Preparation of Pressure-Sensitive Adhesive Layer (1)] [Preparation of acrylic resin solution] A reaction vessel equipped with a condenser, nitrogen inlet, thermometer, and stirrer was charged with a mixed solution of 100 parts ethyl acetate, 99.0 parts butyl acrylate, 0.5 parts 2-hydroxyethyl acrylate, and 0.5 parts acrylic acid. The air in the vessel was purged with nitrogen gas to remove oxygen, and the internal temperature was raised to 55°C. A solution of 0.12 parts azobisisobutyronitrile (polymerization initiator) in 10 parts ethyl acetate was then added in its entirety. After the addition of the polymerization initiator, the temperature was maintained for 1 hour. Ethyl acetate was then continuously added to the reaction vessel at a rate of 17.3 parts / hour while maintaining the internal temperature at 54-56°C. When the (meth)acrylic resin concentration reached 35% by mass, the ethyl acetate addition was stopped. The temperature was maintained for 6 hours after the start of the ethyl acetate addition. Finally, ethyl acetate was added to adjust the (meth)acrylic resin concentration to 20% by mass, preparing an acrylic resin solution. The resulting acrylic resin had a weight-average molecular weight Mw of 1.7 million and a molecular weight distribution Mw / Mn of 3.9. Mw and Mn were measured in terms of standard polystyrene using two Tosoh Corporation "TSKgel GMHHR-H(S)" columns connected in series in a GPC system, tetrahydrofuran as the eluent, a sample concentration of 2 mg / mL, a sample introduction amount of 100 μL, a temperature of 40°C, and a flow rate of 1 mL / min.

[0152] [Preparation of Pressure-Sensitive Adhesive Composition] To 80 parts by solid content of the acrylic resin solution obtained above, 20 parts (solid content) of a bifunctional acrylate (obtained from Shin-Nakamura Chemical Co., Ltd.; product number "A-DOG"), 2.5 parts based on the active ingredient of a crosslinking agent (manufactured by Tosoh Corporation; trade name "Coronate L" (ethyl acetate solution of trimethylolpropane adduct of tolylene diisocyanate (solid content concentration: 75% by mass)), 1.5 parts of a photoinitiator (manufactured by Ciba Specialty Chemicals; trade name "Irgacure 500"), and 0.3 part of a silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.; trade name "KBM-403") were added, and further ethyl acetate was added so that the solid content concentration became 13% to obtain an adhesive composition. A-DOG is a diacrylate of an acetal compound of hydroxypivalaldehyde and trimethylolpropane.

[0153] [Preparation of Adhesive Sheet (1)] The adhesive composition prepared above was applied to the release-treated surface of a separate film (PET separate film 1) made of a polyethylene terephthalate film with a release treatment [obtained from Lintec Corporation's "PLZ-383030"] using an applicator so that the thickness after drying would be 5 μm, and dried at 100°C for 1 minute to produce an adhesive layer (adhesive sheet). Next, the surface of the obtained adhesive layer opposite to the PET separator film 1 was bonded to the release-treated surface of a separate film (PET separate film 2 [obtained from Lintec Corporation's "PLR-381031"]) made of a polyethylene terephthalate film with a release treatment. Subsequently, ultraviolet rays were irradiated under the following UV irradiation conditions to produce an adhesive sheet (1). The adhesive sheet (1) had a layer structure of PET separate film 1 / adhesive layer (1) / PET separate film 2. <UV Irradiation Conditions> ·Using an H bulb of a Fusion UV lamp system (manufactured by Fusion UV Systems) ·Integrated light quantity: 250 mJ / cm 2

[0154] The oxygen barrier layer (A) side of the vertical polarizing film (1) with an oxygen barrier layer obtained above was attached to one side of the ultraviolet absorbing film (A) via the pressure-sensitive adhesive layer (1) obtained by peeling off the PET separate film 1 and the PET separate film 2 from the pressure-sensitive adhesive sheet (1), thereby obtaining an optical laminate (1). The obtained optical laminate (1) has a layer structure of ultraviolet absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (A) / vertical polarizing film (cured film A / aligned film A) / protective layer / polyethylene terephthalate film. The pressure-sensitive adhesive layer (1) used is colorless and transparent to the naked eye and has a light transmittance T 380 is 90% or more, and the light transmittance T 400 is 90% or more, and the light transmittance T 450 The light transmittance T at a wavelength of 380 nm of the ultraviolet absorbing film (A) / adhesive layer (1) / oxygen barrier layer (A) was measured by peeling off the vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film from the optical laminate (1). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T 450 is 90%.

[0155] [Preparation of Polarizer] A polyvinyl alcohol film having a thickness of 20 μm, a degree of polymerization of 2400, and a degree of saponification of 99% or more was uniaxially stretched to a stretching ratio of 4.5 times on a heated roll, and while maintaining tension, was immersed for 60 seconds in a dye bath at 28°C containing 0.05 parts by mass of iodine and 5 parts by mass of potassium iodide per 100 parts by mass of water.

[0156] Next, the film was immersed for 110 seconds in a boric acid aqueous solution 1 at 64°C containing 5.5 parts by mass of boric acid and 15 parts by mass of potassium iodide per 100 parts by mass of water. The film was then immersed for 30 seconds in a boric acid aqueous solution 2 at 67°C containing 5.5 parts by mass of boric acid and 15 parts by mass of potassium iodide per 100 parts by mass of water. The film was then washed with pure water at 10°C and dried to obtain a polarizer. The polarizer had a thickness of 8 μm and a boron content of 4.3% by mass.

[0157] [Preparation of Retardation Film] An unstretched, continuous cycloolefin resin (COP) film having a glass transition temperature (Tg) of 125°C and a thickness of 40 μm was uniaxially stretched transversely by approximately 1.5 times in an atmosphere of 128°C to obtain a continuous retardation film having a thickness of 30 μm. The transverse uniaxial stretching was performed using a tenter-type stretching machine. The in-plane retardation value Re(λ) of this continuous retardation film was measured using a measuring instrument (Oji Scientific Instruments Co., Ltd., "KOBRA-WPR"), and the in-plane retardation Re(550) at a wavelength of λ = 550 nm was 100 nm, and the in-plane retardation Re(450) at a wavelength of λ = 450 nm was 103 nm. The slow axis direction was at an angle of 90° to the length direction of the retardation film, i.e., the width direction.

[0158] [Preparation of composition for forming alignment film B] The photoalignment material (weight average molecular weight: 50,000, m:n = 50:50) having the following structure was produced in accordance with the method described in JP 2021-196514 A. 2 parts of the photoalignment material and 98 parts of cyclopentanone (solvent) were mixed as components, and the resulting mixture was stirred at 80° C. for 1 hour to obtain a composition for forming alignment film B. [ka]

[0159] [Preparation of polymerizable liquid crystal compound] Polymerizable liquid crystal compound (A1) and polymerizable liquid crystal compound (A2) having the structures shown below were prepared. Polymerizable liquid crystal compound (A1) was prepared in the same manner as described in JP-A-2019-003177. Polymerizable liquid crystal compound (A2) was prepared in the same manner as described in JP-A-2009-173893. Polymerizable liquid crystal compound (A1): [ka] Polymerizable liquid crystal compound (A2): [ka]

[0160] A solution was obtained by dissolving 1 mg of polymerizable liquid crystal compound (A1) in 10 mL of chloroform. The obtained solution was placed in a measurement cell with an optical path length of 1 cm, and the measurement sample was placed in an ultraviolet-visible spectrophotometer (Shimadzu Corporation, "UV-2450") to measure the absorption spectrum. The wavelength at which the maximum absorbance was obtained was read from the obtained absorption spectrum, and the maximum absorption wavelength λmax in the wavelength range of 300 to 400 nm was 356 nm.

[0161] [Preparation of polymerizable liquid crystal composition for forming retardation film] Polymerizable liquid crystal compound (A1) and polymerizable liquid crystal compound (A2) were mixed in a mass ratio of 90:10 to obtain a mixture. To 100 parts of the obtained mixture, 0.1 parts of a leveling agent "BYK-361N" (manufactured by BM Chemie) and 3 parts of a photopolymerization initiator "Irgacure OXE-03" (manufactured by BASF Japan Ltd.) were added. Furthermore, N-methyl-2-pyrrolidone (NMP) was added so that the solids concentration became 13%. The mixture was stirred at 80°C for 1 hour to prepare a retardation film-forming polymerizable liquid crystal composition.

[0162] [Preparation of Retardation Film] The surface of a cycloolefin polymer (COP film) (Zeon Corporation, ZF-14-50) was treated once using a corona treatment device (AGF-B10; Kasuga Electric Co., Ltd.) at an output of 0.3 kW and a treatment speed of 3 m / min. The composition for forming alignment film B was applied to the corona-treated surface of the protective layer using a bar coater. The resulting coating was dried at 120°C for 2 minutes and then cooled to room temperature to form a dried film. Subsequently, the film was irradiated with 100 mJ of polarized ultraviolet light (313 nm standard) using a UV irradiation device (SPOT CURE SP-9; Ushio Inc.) to obtain alignment film (B). The thickness of alignment film (B) was measured using an ellipsometer M-220 manufactured by JASCO Corporation and was 100 nm.

[0163] The above-mentioned polymerizable liquid crystal composition for forming a retardation film was applied onto the obtained alignment film (B) using a bar coater to form a coating film. This coating film was dried by heating at 120°C for 2 minutes and then cooled to room temperature to obtain a dried film. Next, using a high-pressure mercury lamp ("Uniquer VB-15201BY-A" manufactured by Ushio Inc.), the exposure dose was 500 mJ / cm under a nitrogen atmosphere. 2 The dried film was irradiated with ultraviolet light (365 nm standard) to form a retardation film in which the polymerizable liquid crystal compound was cured in a state of being aligned horizontally relative to the substrate surface, and a laminate film with a retardation film was obtained, consisting of COP film (ZF-14-50) / alignment film (B) / cured film B (horizontally aligned liquid crystal cured film). The thickness of the retardation film measured using a laser microscope LEXT OLS4100 manufactured by Olympus Corporation was 2.0 μm.

[0164] The retardation film side of the retardation film-coated laminate film was corona-treated and then attached to glass using a 25 μm pressure-sensitive adhesive manufactured by Lintec Corporation. The in-plane retardation values ​​were measured using a KOBRA-WR manufactured by Oji Scientific Instruments. The in-plane retardation values ​​for light with wavelengths of 450 nm, 550 nm, and 650 nm were calculated using Cauchy's dispersion formula, which was obtained from the in-plane retardation values ​​measured for light with wavelengths of 448.2 nm, 498.6 nm, 548.4 nm, 587.3 nm, 628.7 nm, and 748.6 nm. As a result, the in-plane retardation values ​​were Re(450) = 120 nm and Re(550) = 142 nm, and the relationship between the in-plane retardation values ​​at each wavelength was as follows: Note that the retardation value of the COP film (ZF-14-50) at a wavelength of 550 nm is approximately 0, so there is no effect on the optical properties. Re(450) / Re(550)=0.85 (In the formula, Re(450) represents the in-plane retardation value for light with a wavelength of 450 nm, and Re(550) represents the in-plane retardation value for light with a wavelength of 550 nm.)

[0165] [Preparation of Polarizing Plate] The retardation film obtained above was cut into sheets, and one side of each sheet was subjected to a corona treatment. The polarizer obtained above was superimposed on the corona-treated surface of the corona-treated retardation film using a nip roll via an aqueous adhesive. The superimposed retardation film and polarizer were dried at 80°C for 3 minutes while applying tension to obtain a polarizing plate in which the retardation film was laminated on one side of the polarizer. The layer structure of this polarizing plate was polarizer / aqueous adhesive / retardation film.

[0166] The retardation film and the polarizer were superposed so that the relative angle between the slow axis of the retardation film and the absorption axis of the polarizer was 45 degrees, and the films were laminated while maintaining this relative angle.

[0167] The water-based adhesive used was prepared by adding 3 parts by weight of carboxyl-modified polyvinyl alcohol (Kuraray Poval KL318 manufactured by Kuraray Co., Ltd.) and 1.5 parts by weight of a water-soluble polyamide epoxy resin aqueous solution (Sumirez Resin 650 manufactured by Sumika Chemtex Co., Ltd., solids concentration 30% by weight) to 100 parts of water.

[0168] [Preparation of Circularly Polarizing Plate] The polyethylene terephthalate film was peeled off from the optical laminate (1) obtained above to expose the protective layer side, and the polarizing plate obtained above was then laminated on the retardation film side to the exposed protective layer via an adhesive layer similar to the adhesive layer (1) described above. Next, the retardation film formed on the COP film (ZF-14-50) described above was laminated to the polarizer-side surface of the polarizing plate laminated on the vertical polarizing film via an adhesive layer similar to the adhesive layer (1) described above. When laminating, the relative angle between the slow axis of the retardation film and the absorption axis of the polarizer was set to 135 degrees.

[0169] This produced a circular polarizing plate containing the following in this order: UV-absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (A) / vertical polarizing film (cured film A / alignment film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B / alignment film B) / COP film (ZF-14-50). This circular polarizing plate was achromatic, gray, and transparent when viewed from the front.

[0170] Example 2 A vertical polarizing film (2) with an oxygen barrier layer (2) was obtained in the same manner as in Example 1, except that in the preparation of the oxygen barrier layer (A), the curable composition for forming an oxygen barrier layer (1) was applied while adjusting the thickness of the oxygen barrier layer to 0.5 μm to form an oxygen barrier layer (B) with a thickness of 0.5 μm. An optical laminate (2) was obtained in the same manner as in Example 1, except that the vertical polarizing film with an oxygen barrier layer (2) obtained above was used instead of the vertical polarizing film with an oxygen barrier layer (1) obtained in Example 1. A circular polarizing plate was produced in the same manner as in Example 1, except that the optical laminate (2) was used instead of the optical laminate (1). The circular polarizing plate had a layer structure of ultraviolet absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (B) / vertical polarizing film (cured film A / aligned film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B / aligned film B) / COP film (ZF-14-50). This circular polarizing plate was achromatic gray and transparent when viewed from the front. The light transmittance T of the ultraviolet absorbing film (A) / adhesive layer (1) / oxygen barrier layer (B) at a wavelength of 380 nm was measured by peeling off the vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film from the optical laminate (2). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T 450 was 90%.

[0171] Example 3 A vertical polarizing film (3) with an oxygen barrier layer was obtained in the same manner as in Example 1, except that in the preparation of the oxygen barrier layer, the curable composition for forming an oxygen barrier layer (1) was applied while adjusting the thickness of the oxygen barrier layer to 1.0 μm to form an oxygen barrier layer (C) with a thickness of 1.0 μm. This vertical polarizing film (3) with an oxygen barrier layer had a layer structure of oxygen barrier layer (C) / vertical polarizing film (cured film A / alignment film A) / protective layer / PET film (Diafoil T140E25). An optical laminate (3) was obtained in the same manner as in Example 1, except that the vertical polarizing film with an oxygen barrier layer (3) obtained above was used instead of the vertical polarizing film with an oxygen barrier layer (1) obtained in Example 1, and a circular polarizing plate was produced in the same manner as in Example 1, except that the optical laminate (3) was used instead of the optical laminate (1). This circular polarizing plate has a layer structure of ultraviolet absorbing film (A) / adhesive layer (1) / oxygen barrier layer (C) / vertical polarizing film (cured film A / aligned film A) / protective layer / adhesive layer / retardation film / water-based adhesive layer / polarizer / adhesive layer / retardation film (cured film B / aligned film B) / COP film (ZF-14-50). When viewed from the front, this circular polarizing plate was achromatic gray and transparent. The light transmittance T of the ultraviolet absorbing film (A) / adhesive layer (1) / oxygen barrier layer (C) at a wavelength of 380 nm was measured by peeling off the vertical polarizing film (cured film A / aligned film A) / protective layer / polyethylene terephthalate film from the optical laminate (3). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T 450 was 90%.

[0172] Example 4 A vertical polarizing film (4) with an oxygen barrier layer (4) was obtained in the same manner as in Example 1, except that the oxygen barrier layer was formed by applying the curable composition for forming an oxygen barrier layer (1) while adjusting the thickness of the oxygen barrier layer to 3.0 μm to form an oxygen barrier layer (D) with a thickness of 3.0 μm. An optical laminate (4) was obtained in the same manner as in Example 1, except that the vertical polarizing film with an oxygen barrier layer (4) obtained above was used instead of the vertical polarizing film with an oxygen barrier layer (1) obtained in Example 1. A circular polarizing plate was produced in the same manner as in Example 1, except that the optical laminate (4) obtained above was used instead of the optical laminate (1). This circular polarizing plate has a layer structure of ultraviolet absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (D) / vertical polarizing film (cured film A / aligned film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B / aligned film B) / COP film (ZF-14-50). This circular polarizing plate was achromatic gray and transparent when viewed from the front. The light transmittance T of the ultraviolet absorbing film (A) / adhesive layer (1) / oxygen barrier layer (D) at a wavelength of 380 nm was measured by peeling off the vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film from the optical laminate (4). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T 450 was 90%.

[0173] Example 5 [Preparation of oxygen barrier layer-forming composition (5)] 3.8 parts by mass of polyvinyl alcohol ("Z320" manufactured by Mitsubishi Chemical Corporation) was dissolved in 100 parts by mass of pure water and mixed to prepare a curable composition (5) for forming an oxygen barrier layer.

[0174] [Preparation of Circularly Polarizing Plate] A vertical polarizing film (5) with an oxygen barrier layer was obtained in the same manner as in Example 1, except that the oxygen barrier layer-forming composition (1) was replaced with the oxygen barrier layer-forming composition (5) obtained above, and the curable composition (5) for forming an oxygen barrier layer was applied while adjusting the thickness of the formed oxygen barrier layer to 1.0 μm to form an oxygen barrier layer (E). A circular polarizing plate was produced in the same manner as in Example 1, except that the vertical polarizing film (1) with an oxygen barrier layer obtained in Example 1 was replaced with the vertical polarizing film (5) with an oxygen barrier layer obtained above. This circular polarizing plate was achromatic gray and transparent when viewed from the front. The light transmittance T of the ultraviolet-absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (E) at a wavelength of 380 nm was measured by peeling the vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film from the optical laminate (5). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T at a wavelength of 450 nm 450 was 90%.

[0175] Example 6 [Preparation of oxygen barrier layer-forming composition (6)] 3.8 parts by mass of polyvinyl alcohol ("Z200" manufactured by Mitsubishi Chemical Corporation) was dissolved in 100 parts by mass of pure water and mixed to prepare a curable composition (6) for forming an oxygen barrier layer.

[0176] [Preparation of Circularly Polarizing Plate] A vertical polarizing film (6) with an oxygen barrier layer was obtained in the same manner as in Example 1, except that the oxygen barrier layer-forming composition (1) was replaced with the curable composition (6) for forming an oxygen barrier layer obtained above, and the oxygen barrier layer (F) was formed with a thickness of 1.0 μm by applying the composition (6) while adjusting the thickness of the oxygen barrier layer to 1.0 μm. A circular polarizing plate was produced in the same manner as in Example 1, except that the vertical polarizing film (6) with an oxygen barrier layer obtained above was used instead of the vertical polarizing film (1) with an oxygen barrier layer. This circular polarizing plate was achromatic gray and transparent when viewed from the front. The light transmittance T of the ultraviolet-absorbing film (A) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (F) at a wavelength of 380 nm was measured by peeling the vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film from the optical laminate (6). 380 is 5%, and the light transmittance T 400 is 84%, and the light transmittance T 450 was 90%.

[0177] Example 7 [Preparation of UV-absorbing film (B)] As the ultraviolet absorbing film (B), a film was obtained and used in which an ultraviolet absorbing layer was formed on one side of a cycloolefin resin film (COP film) ["ZEONORFILM G+" manufactured by Nippon Zeon Co., Ltd.]. The light transmittance (T 380 ) is 0.1% or less, and the light transmittance at a wavelength of 400 nm (T 400 The light transmittance (T) of this ultraviolet absorbing film (B) at a wavelength of 450 nm was 2%. 450 ) is 87%, and the light transmittance at a wavelength of 550 nm (T 550 ) is 90% or more, and the light transmittance at a wavelength of 650 nm (T 650 ) was 90% or more, and it was colorless and transparent to the naked eye. The in-plane retardation (wavelength 550 nm) of this ultraviolet absorbing film (B) was 1.7 nm.

[0178] This ultraviolet absorbing film (B) can be produced by, for example, subjecting one side of a cycloolefin resin film (Zeonorfilm G+) to a corona discharge treatment, obtaining a photoselective absorbing compound (1) by the method described in paragraph 0151 of JP 2019-8292 A, preparing an active energy ray-curable resin composition A1 by the method described in paragraph 0155, applying the active energy ray-curable resin composition A1 to the corona discharge-treated surface of the cycloolefin resin film (Zeonorfilm G+) using a bar coater, and irradiating ultraviolet light using a belt conveyor-equipped ultraviolet irradiation device (using an "H Bulb" ultraviolet lamp manufactured by Fusion UV Systems). An ultraviolet absorbing layer can be formed on one side of the cycloolefin resin film (Zeonorfilm G+). This ultraviolet absorbing film (B) has a layer structure of COP film (Zeonorfilm G+) / ultraviolet absorbing layer.

[0179] [Preparation of optical laminate (7)] A vertical polarizing film (3) with an oxygen barrier layer was obtained in the same manner as in Example 3. The oxygen barrier layer surface of the vertical polarizing film (3) with an oxygen barrier layer was bonded to the COP film (ZEONORFILM G+) side of the ultraviolet-absorbing film (B) obtained above, via a pressure-sensitive adhesive layer (1), to obtain an optical laminate (7). This optical laminate (7) has a layer structure of ultraviolet-absorbing film (B) (ultraviolet-absorbing layer / COP film (ZEONORFILM G+)) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (C) / vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film. The vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film was peeled from the optical laminate (7), and the light transmittance T of the ultraviolet-absorbing film (B) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (C) at a wavelength of 380 nm was measured. 380 is 0.1% or less, and the light transmittance T 400 is 2%, and the light transmittance T 450 was 87%.

[0180] [Preparation of Circularly Polarizing Plate] A circularly polarizing plate was produced in the same manner as in Example 1, except that the optical laminate (7) obtained above was used instead of the optical laminate (1). This circularly polarizing plate had a layer structure of ultraviolet absorbing film (B) (ultraviolet absorbing layer / COP film (ZEONORFILM G+)) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (C) / vertical polarizing film (cured film A / aligned film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B / aligned film B) / COP film (ZF-14-50). This circularly polarizing plate was achromatic gray and transparent when viewed from the front.

[0181] Example 8 [Preparation of adhesive sheet (8)] An acrylic resin (A) was prepared according to the method described in paragraph 0247 of JP 2017-120430 A. An ultraviolet absorber UVA-02 was also obtained according to Synthesis Example 2 described in paragraph 0258. According to the blending ratios according to Production Example 3 described in Table 2 in paragraph 0292, per 100 parts by mass of the solid content of the acrylic resin (A) obtained above, the ultraviolet absorber UVA-02 obtained above (0.61 parts by mass), 0.50 parts by mass of a crosslinker ("Coronate L" manufactured by Nippon Polyurethane Co., Ltd., an ethyl acetate solution of a trimethylolpropane adduct of tolylene diisocyanate (solid content concentration 75% by mass)), and 0.50 parts by mass of a silane compound ("KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd., 3-glycidoxypropyltrimethoxysilane (liquid)) were blended, and 2-butanone was added to obtain an ultraviolet-absorbing pressure-sensitive adhesive composition.

[0182] The ultraviolet-absorbing pressure-sensitive adhesive composition obtained above was applied to the release-treated surface of a release film ("SP-PL-R382050" manufactured by Lintec Corporation, a polyethylene terephthalate film (PET film)) with a release-treated surface using an applicator so that the film would have a dry thickness of 20 μm, and the composition was dried at 100° C. for 1 minute to form an ultraviolet-absorbing pressure-sensitive adhesive layer (8), thereby producing an ultraviolet-absorbing pressure-sensitive adhesive sheet (8). This ultraviolet-absorbing pressure-sensitive adhesive sheet (8) has a layer structure of PET film (SP-PL-R382050) / ultraviolet-absorbing pressure-sensitive adhesive layer (8). This ultraviolet-absorbing pressure-sensitive adhesive layer (8) is colorless and transparent to the naked eye and has a light transmittance T 380 is 0.1% or less, and the light transmittance T 400 is 0.1% or less, and the light transmittance T 450 was over 90%.

[0183] [Preparation of optical laminate (8)]

[0184] The same cycloolefin resin film (ZEONORFILM G+) as used in Example 1 was prepared as the ultraviolet absorbing film. The ultraviolet absorbing pressure-sensitive adhesive sheet (8) prepared above was attached to one surface of this ultraviolet absorbing film (A) with the ultraviolet absorbing pressure-sensitive adhesive layer (8) side to obtain a laminate (8). The layer structure of this laminate (8) was ultraviolet absorbing film (A) / ultraviolet absorbing pressure-sensitive adhesive layer / PET film (SP-PL-R382050). The PET film (SP-PL-R382050) was peeled off from this laminate (8) to measure the light transmittance, and the light transmittance at a wavelength of 380 nm, T 380 is 5%, and the light transmittance T 400 The light transmittance at a wavelength of 450 nm is 84%. 450 The in-plane retardation (wavelength 550 nm) of this ultraviolet absorbing film was 1.7 nm.

[0185] A vertical polarizing film (3) with an oxygen barrier layer was obtained in the same manner as in Example 3. This vertical polarizing film (3) with an oxygen barrier layer had a layer structure of oxygen barrier layer (C) / vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film. The PET film (SP-PL-R382050) was peeled off from the laminate (8) obtained above to expose the ultraviolet-absorbing pressure-sensitive adhesive layer (8), which was then attached to the oxygen barrier layer (C) side of the vertical polarizing film (3) with an oxygen barrier layer to obtain an optical laminate (8). This optical laminate (8) had a layer structure of ultraviolet-absorbing film (A) / ultraviolet-absorbing pressure-sensitive adhesive layer (8) / oxygen barrier layer (C) / vertical polarizing film (cured product layer A / alignment film A) / protective layer / polyethylene terephthalate film. The vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film was peeled off from the optical laminate (8), and the light transmittance T at a wavelength of 380 nm of the ultraviolet absorbing film (A) / ultraviolet absorbing adhesive layer (8) / oxygen barrier layer (C) was measured. 380 is 0.1% or less, and the light transmittance T 400 is 0.1% or less, and the light transmittance T 450 was 90%. [Preparation of Circularly Polarizing Plate]

[0186] A circularly polarizing plate was produced in the same manner as in Example 1, except that the optical laminate (1) obtained in Example 1 was replaced with the optical laminate (8) obtained above. This circular polarizer had a layer structure including, in this order: UV-absorbing film (A) / UV-absorbing adhesive layer (8) / oxygen barrier layer (C) / vertical polarizing film (cured film A / alignment film A) / protective layer / adhesive layer / retardation film / water-based adhesive layer / polarizer / adhesive layer / retardation film (cured film B and alignment film B) / COP film (ZF-14-50). When viewed from the front, this circular polarizer was achromatic gray and transparent.

[0187] Example 9 An optical laminate (9) was obtained in the same manner as in Example 7, except that the vertical polarizing film with an oxygen barrier layer (3) was replaced with the vertical polarizing film with an oxygen barrier layer (6) obtained in Example 6. This optical laminate (9) had a layer structure of ultraviolet absorbing film (B) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (F) / vertical polarizing film (cured film A / alignment film A) / protective layer / polyethylene terephthalate film.

[0188] A circularly polarizing plate was obtained in the same manner as in Example 7, except that the optical laminate (9) obtained above was used instead of the optical laminate (7). This circularly polarizing plate had a layer structure of ultraviolet absorbing film (B) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (F) / vertical polarizing film (cured film A / aligned film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B / aligned film B) / COP film (ZF-14-50). This circularly polarizing plate was achromatic gray and transparent when viewed from the front. The light transmittance T of the ultraviolet absorbing film (B) / pressure-sensitive adhesive layer (1) / oxygen barrier layer (F) at a wavelength of 380 nm was measured by peeling off the vertical polarizing film (cured film A / aligned film A) / protective layer / polyethylene terephthalate film from the optical laminate (9). 380 is 0.1% or less, and the light transmittance T 400 is 2%, and the light transmittance T 450 was 87%.

[0189] Example 10

[0190] An optical laminate (10) was obtained in the same manner as in Example 8, except that the vertical polarizing film with an oxygen barrier layer (3) was replaced with the vertical polarizing film with an oxygen barrier layer (6) obtained in Example 6. This optical laminate (10) had a layer structure of ultraviolet-absorbing film (A) / ultraviolet-absorbing pressure-sensitive adhesive layer (8) / oxygen barrier layer (F) / vertical polarizing film (cured product layer A / alignment film A) / protective layer / polyethylene terephthalate film.

[0191] A circularly polarizing plate was obtained in the same manner as in Example 1, except that the optical laminate (10) obtained above was used instead of the optical laminate (7). This circularly polarizing plate had a structure of ultraviolet-absorbing film (A) / ultraviolet-absorbing pressure-sensitive adhesive layer (8) / oxygen barrier layer (F) / vertical polarizing film (cured film A / aligned film A) / protective layer / pressure-sensitive adhesive layer / retardation film / water-based adhesive layer / polarizer / pressure-sensitive adhesive layer / retardation film (cured film B and aligned film B) / COP film (ZF-14-50). When viewed from the front, this circularly polarizing plate was achromatic gray and transparent. The light transmittance T of the ultraviolet-absorbing film (A) / ultraviolet-absorbing pressure-sensitive adhesive layer (8) / oxygen barrier layer (F) at a wavelength of 380 nm was measured by peeling off the vertical polarizing film (cured film A / aligned film A) / protective layer / polyethylene terephthalate film from the optical laminate (10). 380 is 0.1% or less, and the light transmittance T 400 is 0.1% or less, and the light transmittance T 450 was 90%.

[0192] [Lightfastness Evaluation] Each circularly polarizing plate prepared in each example was attached to an inorganic glass plate with the COP film (ZF-14-50) side via an adhesive to prepare an evaluation sample. The plate was placed in a xenon weathering tester ("Atlas Ci4400" manufactured by DJK Co., Ltd.) with the ultraviolet absorbing film side facing the light source, and the output at a wavelength of 420 nm was 2.4 W / m 2 The test piece was then placed in the xenon weathering tester again and held under the above conditions for a further 160 hours (total holding time was 240 hours), and then evaluated again using the following method.

[0193] The evaluation sample was taken out of the xenon light resistance tester and placed on a backlight with the inorganic glass plate side facing the light source. The evaluation sample was then rotated in-plane from a direction obliquely at 45° to the front of the evaluation sample (light-absorbing film side), and the coloration of the transmitted light was visually observed from all directions, and evaluated according to the following criteria. A: Almost no color change was observed in the transmitted light. B: Almost no color change was observed. C: Slight discoloration was observed D: Significant discoloration was observed

[0194] The evaluation results are shown in Tables 1 and 2. The coloration of transmitted light was observed in the same manner for the evaluation samples before they were placed in the xenon light resistance tester, and the evaluation was "A" for all Examples.

[0195] [Table 1]

[0196] [Table 2] [Explanation of symbols]

[0197] 1: Vertical polarizer 2: UV absorbing film 3: Oxygen barrier layer 4: Vertical polarizer 5: Linear polarizer 6: Retardation plate 11: Composite linear polarizer 12: Circular polarizer

Claims

1. an ultraviolet absorbing film; an oxygen barrier layer; a vertical polarizing film in which a dichroic dye is vertically oriented, and a vertical polarizing film in which a dichroic dye is vertically oriented are laminated in this order directly or via an adhesive layer; The direction of an arbitrary position on the film surface is the x-axis, the direction perpendicular to the x-axis on the film surface is the y-axis, and the x-axis and y When the film thickness direction perpendicular to the axis is defined as the z axis, the following formulas (1) to (3): Az>(Ax+Ay) / 2 (1) Ax (z=60°) / Ax>5 (2) Ay (z=60°) / Ay>5 (3) [In formulas (1) to (3), Ax, Ay, Az, Ax(z=60°) and Ay(z=60°) are all absorbances at the absorption maximum wavelength of the dichroic dye in the optically absorptive anisotropic film, Ax represents the absorbance of linearly polarized light vibrating in the x-axis direction, Ay represents the absorbance of linearly polarized light vibrating in the y-axis direction, Az represents the absorbance of linearly polarized light vibrating in the z-axis direction, Ax (z=60°) represents the absorbance of linearly polarized light oscillating in the x-axis direction when the film is rotated 60° around the y-axis, Ay (z=60°) represents the absorbance of linearly polarized light oscillating in the y-axis direction when the film is rotated 60° around the x-axis. Satisfied, The light transmittance (T ３８０ ) is 10% or less.

2. 2. The vertical polarizer according to claim 1, wherein the oxygen barrier layer has a thickness of 0.1 μm or more and 10 μm or less.

3. 3. The vertical polarizing plate according to claim 1, wherein the oxygen barrier layer is a polyvinyl alcohol-based resin layer having a saponification degree of 30 or more.

4. The light transmittance (T ４００ 2. The vertical polarizer according to claim 1, wherein the difference between the polarity of the polarizer and the polarity of the polarizer is 10% or less.

5. The light transmittance (T ４５０ 2. The vertical polarizing plate according to claim 1, wherein the ratio of the polarity of the polarizer to the polarizer is 70% or more.

6. A composite linear polarizing plate comprising a linear polarizing plate having a polyvinyl alcohol polarizer in which a dichroic dye is oriented in a polyvinyl alcohol-based resin film, laminated on the opposite side of the oxygen barrier layer of the vertical polarizing film of the vertical polarizing plate described in any one of claims 1 to 5.

7. A circular polarizer obtained by laminating a retardation plate on the side of the linear polarizer opposite to the vertical polarizer of the composite linear polarizer according to claim 6 .

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