Laminated film, circular polarizer, display device

Abstract

To provide a laminate film, including a plurality of optical anisotropic layers, that is superior in transparency, and has less point defects and also emits less reflected light in a black display state of a display device when applied to the display device, and provide a circular polarization plate, and the display device.SOLUTION: The present invention relates to a laminate film that has a first optical anisotropic layer, a second optical anisotropic layer, a third optical anisotropic layer, and a fourth optical anisotropic layer in this order. Any of the first optical anisotropic layer, second optical anisotropic layer, third optical anisotropic layer, and fourth optical anisotropic layer is formed by fixing an aligned liquid crystal compound, and the laminate film has a contact layer selected from the group of an adhesive layer and a pressure-sensitive adhesive layer only one of between the first optical anisotropic layer and second optical anisotropic layer, between the second optical anisotropic layer and third optical anisotropic layer, and between the third optical anisotropic layer and fourth optical anisotropic layer, the laminate film having a minimum transmittance of 60% or larger at a wavelength of 400 to 700 nm.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a laminated film, a circular polarizing plate, and a display device. [Background technology]

[0002] Optical anisotropy layers formed using liquid crystal compounds are being applied in various fields, including the display industry. For example, Patent Document 1 discloses a phase difference film including a positive A plate, a first positive C plate, and a λ / 4 plate, and a circular polarizer including this phase difference film. More specifically, Patent Document 1 discloses a circular polarizer having a polarizer, a positive A plate, a first positive C plate, a λ / 4 plate, and a second positive C plate in that order, and each layer is formed by bonding them together via an adhesive layer. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 6773887 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The present inventors manufactured a phase difference film containing multiple optically anisotropic layers using the lamination method disclosed in Patent Document 1 and applied it to a display device. When the resulting display device was set to display black, a large amount of reflected light was observed, indicating that its reduction was necessary. Furthermore, films containing an optically anisotropic layer are required to have fewer point defects.

[0005] In view of the above circumstances, the present invention aims to provide a laminated film comprising multiple optically anisotropic layers that has excellent transparency, few point defects, and is applicable to a display device, and which has low reflected light when the display device is set to black. Another object of the present invention is to provide a circular polarizing plate and a display device. **Means for Solving the Problems**

[0006] As a result of intensive studies to solve the above problems, the inventors of the present invention have completed the present invention with the following configuration.

[0007] (1) A laminated film having a first optically anisotropic layer, a second optically anisotropic layer, a third optically anisotropic layer, and a fourth optically anisotropic layer in this order, wherein the first optically anisotropic layer, the second optically anisotropic layer, the third optically anisotropic layer, and the fourth optically anisotropic layer are all layers formed by fixing an aligned liquid crystal compound, and having an adhesion layer selected from the group consisting of an adhesive layer and an adhesive layer only in any one of the spaces between the first optically anisotropic layer and the second optically anisotropic layer, between the second optically anisotropic layer and the third optically anisotropic layer, and between the third optically anisotropic layer and the fourth optically anisotropic layer, The laminated film has a minimum transmittance of 60% or more in the wavelength range of 400 to 700 nm. (2) The laminated film according to (1), which satisfies one or two of the requirements X1 to X3 described below. (3) The laminated film according to (1) or (2), which satisfies any one of the requirements Y1 to Y3 described below. (4) The laminated film according to any one of (1) to (3), wherein the first optically anisotropic layer and the second optically anisotropic layer are in direct contact, an adhesion layer is disposed between the second optically anisotropic layer and the third optically anisotropic layer, and the third optically anisotropic layer and the fourth optically anisotropic layer are in direct contact. (5) The laminated film according to any one of (1) to (4), wherein the adhesion layer is a layer formed using an ultraviolet curable adhesive. (6) The laminated film according to any one of (1) to (5), having a thickness of 20 μm or less. (7) The laminated film according to any one of (1) to (6), having an in-plane retardation of 100 to 180 nm at a wavelength of 550 nm. A circular polarizing plate comprising the laminated film according to any one of (1) to (7) and a polarizer. (9) The circular polarizing plate according to (8), which does not have a polymer film between the laminated film and the polarizer. (10) A display device including the laminated film according to any one of (1) to (7), or the circular polarizing plate according to (8) or (9).

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a laminated film including a plurality of optically anisotropic layers, which has excellent transparency, few point defects, and when applied to a display device and the display device is in a black display state, has little reflected light. Further, according to the present invention, it is possible to provide a circular polarizing plate and a display device.

Brief Description of the Drawings

[0009] [Figure 1] It is a schematic cross-sectional view showing an example of the laminated film of the present invention. [Figure 2] It is a schematic cross-sectional view showing another example of the laminated film of the present invention. [Figure 3] It is a schematic cross-sectional view showing another example of the laminated film of the present invention.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value. In this specification, "(meth)acrylic" is used to mean "either acrylic or methacrylic, or both." "(meth)acrylate" is used to mean "either acrylate or methacrylate, or both." "(meth)acryloyl" is used to mean "either acryloyl or methacryloyl, or both."

[0011] In this invention, Re(λ) and Rth(λ) represent the in-plane retardation and thickness-direction retardation at wavelength λ, respectively. Unless otherwise specified, wavelength λ is 550 nm. In this invention, Re(λ) and Rth(λ) are values ​​measured at wavelength λ using an AxoScan, manufactured by Axometrics. By inputting the average refractive index ((nx+ny+nz) / 3) and film thickness (d(μm)) into the AxoScan, Slow axis direction (°) Re(λ)=R0(λ) Rth(λ)=((nx+ny) / 2-nz)×d This is calculated. Note that R0(λ) is a value displayed by AxoScan, and it means Re(λ).

[0012] In this specification, the average refractive index ((nx+ny+nz) / 3) is measured using an Abbe refractometer (NAR-4T, manufactured by Atago Co., Ltd.) with a sodium lamp (λ=589nm) as the light source. Wavelength dependence can be measured using a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.) in combination with an interference filter. For liquid crystal compounds, the average refractive index can be measured by this method on a film immobilized in an optical isotropic phase. Additionally, values ​​from the Polymer Handbook (JOHN WILEY & SONS, INC.) and catalogs of various optical films can be used. Examples of average refractive index values ​​for major optical films are given below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).

[0013] In this specification, "light" means active light or radiation, such as the emission spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV light), X-rays, ultraviolet light, and electron beams (EB). Of these, ultraviolet light is preferred.

[0014] In this specification, plates A and C are defined as follows: There are two types of A plates: positive A plates and negative A plates. When the refractive index in the slow axis direction (the direction in which the refractive index is maximum within the plane) is nx, the refractive index in the direction perpendicular to the slow axis within the plane is ny, and the refractive index in the thickness direction is nz, a positive A plate satisfies the relationship in equation (A1), and a negative A plate satisfies the relationship in equation (A2). Note that a positive A plate has a positive Rth value, and a negative A plate has a negative Rth value. Formula (A1) nx>ny≒nz Formula (A2) ny <nx≒nz The above "≒" includes not only cases where the two are completely identical, but also cases where they are substantially identical. "Substantially identical" means, for example, that (ny-nz)×d (where d is the film thickness) is -10 to 10 nm, preferably -5 to 5 nm, and that (nx-nz)×d is -10 to 10 nm, preferably -5 to 5 nm, and that that is also included in "nx≒nz". There are two types of C plates: positive C plates and negative C plates. Positive C plates satisfy the relationship in equation (C1), and negative C plates satisfy the relationship in equation (C2). Note that positive C plates show a negative value for Rth, and negative C plates show a positive value for Rth. Formula (C1) nz>nx≒ny Formula (C2) nz <nx≒ny Furthermore, the above "≒" includes not only cases where the two are completely identical, but also cases where they are substantially identical. "Substantially identical" means, for example, that (nx-ny)×d (where d is the thickness of the film) is between 0 and 10 nm, preferably between 0 and 5 nm, which is included in "nx≒ny".

[0015] In this specification, the refractive index of an optically anisotropic layer, such as a layer comprising an A plate, a C plate, and a liquid crystal compound fixed in a torsion orientation along a helical axis extending in the thickness direction, is defined as shown in equation (N1). In equation (N1), nx represents the refractive index in the slow axis direction within the layer plane (the direction in which the refractive index is maximum within the plane), as described above, and ny also represents the refractive index in the direction perpendicular to the slow axis within the plane, as described above. Equation (N1) (Refractive index) = (nx + ny) / 2 In the case where the optically anisotropic layer is a layer in which liquid crystal compounds are fixed along an A plate, a C plate, and a helical axis extending in the thickness direction, the refractive index is considered to be substantially uniform in the direction of film thickness. Furthermore, the refractive index of the adhesion layer is also calculated using the above formula (N1). If the adhesion layer is optically isotropic, the refractive index in any direction within the plane of the adhesion layer is used as the refractive index. The refractive index mentioned above refers to the refractive index at a wavelength of 550 nm. The refractive index can be measured using a reflection spectrophotometer FE3000 (manufactured by Otsuka Electronics Co., Ltd.), as shown in the examples described later. Specifically, the reflection spectrum of the layer for which the refractive index is to be measured is measured using the reflection spectrophotometer FE3000, and the refractive index can be calculated by applying the n-Cauchy dispersion formula to the obtained reflection spectrum.

[0016] A key feature of the laminated film of the present invention is that it includes four optically anisotropic layers, with an adhesion layer positioned at only one location between each optically anisotropic layer, and exhibits a predetermined transmittance. The inventors investigated the cause of excessive reflected light when using the phase difference film described in Patent Document 1 and found that the adhesion layer used to bond each layer was influential. In particular, when an adhesion layer is placed between two optical anisotropic layers, frontal reflection is more likely to occur. In Patent Document 1, since all four optical anisotropic layers are bonded together via an adhesion layer, frontal reflection was prone to occur. Furthermore, the inventors investigated the cause of point defects and found that the manufacturing procedure of the optically anisotropic layer may have an influence. For example, when manufacturing the optically anisotropic layer in a coating process, a winding process may be performed after the optically anisotropic layer is formed, and it was found that point defects are likely to occur when such processing is performed. In order to suppress the above problems, it is preferable to manufacture by lamination via an adhesive layer rather than by manufacturing each layer by continuous coating. Based on the above findings, the inventors have discovered that in a laminated film containing four optically anisotropic layers, by placing an adhesion layer at only one predetermined location, it is possible to suppress both reflected light and point defects.

[0017] The laminated film of the present invention will be described below with reference to the drawings. Figure 1 shows a schematic cross-sectional view of an example of the laminated film of the present invention. The laminated film 10A has a first optical anisotropy layer 12, a second optical anisotropy layer 14, a third optical anisotropy layer 16, and a fourth optical anisotropy layer 18 in this order, and has an adhesion layer 20 between the second optical anisotropy layer 14 and the third optical anisotropy layer 16. As shown in Figure 1, in the laminated film 10A, the adhesion layer 20 is placed only between the second optical anisotropy layer 14 and the third optical anisotropy layer 16, and the adhesion layer 20 is not placed between the first optical anisotropy layer 12 and the second optical anisotropy layer 14, nor between the third optical anisotropy layer 16 and the fourth optical anisotropy layer 18.

[0018] Furthermore, although Figure 1 shows an adhesion layer 20 placed between the second optical anisotropy layer 14 and the third optical anisotropy layer 16, the embodiment is not limited to this. For example, the laminated film 10B, another example shown in Figure 2, has a first optical anisotropy layer 12, a second optical anisotropy layer 14, a third optical anisotropy layer 16, and a fourth optical anisotropy layer 18 in that order, with an adhesion layer 20 between the first optical anisotropy layer 12 and the second optical anisotropy layer 14. As shown in Figure 2, in the laminated film 10B, the adhesion layer 20 is placed only between the first optical anisotropy layer 12 and the second optical anisotropy layer 14, and the adhesion layer 20 is not placed between the second optical anisotropy layer 14 and the third optical anisotropy layer 16, nor between the third optical anisotropy layer 16 and the fourth optical anisotropy layer 18. Furthermore, another example shown in Figure 3, the laminated film 10C, has a first optical anisotropy layer 12, a second optical anisotropy layer 14, a third optical anisotropy layer 16, and a fourth optical anisotropy layer 18 in that order, with an adhesion layer 20 between the third optical anisotropy layer 16 and the fourth optical anisotropy layer 18. As shown in Figure 3, in the laminated film 10C, the adhesion layer 20 is placed only between the third optical anisotropy layer 16 and the fourth optical anisotropy layer 18, and the adhesion layer 20 is not placed between the first optical anisotropy layer 12 and the second optical anisotropy layer 14, nor between the second optical anisotropy layer 14 and the third optical anisotropy layer 16.

[0019] Although not shown in Figures 1-3, as will be described later, other layers (e.g., alignment film, substrate) besides the adhesion layer may be placed between two adjacent optically anisotropic layers.

[0020] The following describes in detail each component that makes up the laminated film.

[0021] <First optical anisotropy layer to fourth optical anisotropy layer> The laminated film has four optical anisotropic layers: a first optical anisotropic layer, a second optical anisotropic layer, a third optical anisotropic layer, and a fourth optical anisotropic layer. The first to fourth optical anisotropic layers are all distinct from each other. Distinct layers are characterized by differences such as the type of liquid crystal compound used to form the optical anisotropic layer, the orientation morphology or direction of the liquid crystal compound within the optical anisotropic layer, and the optical properties of the optical anisotropic layer (e.g., in-plane retardation and thickness-direction retardation).

[0022] The first to fourth optically anisotropic layers are all layers formed by fixing oriented liquid crystal compounds, and it is preferable that the layers are formed by fixing liquid crystal compounds having polymerizable groups by polymerization. In this specification, the term "fixed" refers to a state in which the orientation of the liquid crystal compound is maintained. Specifically, it is preferable that the layer is non-fluid and that the fixed orientation can be stably maintained without causing changes in the orientation due to external fields or forces, typically in a temperature range of 0 to 50°C, or -30 to 70°C under more severe conditions.

[0023] The type of liquid crystal compound is not particularly limited, and generally, liquid crystal compounds can be classified into rod-shaped liquid crystal compounds and disc-shaped liquid crystal compounds based on their shape. Furthermore, each of these can be divided into low-molecular-weight and high-molecular-weight types. High-molecular-weight compounds generally refer to those with a degree of polymerization of 100 or more (Polymer Physics and Phase Transition Dynamics, by Masao Doi, p. 2, Iwanami Shoten, 1992). In this invention, any type of liquid crystal compound can be used, but rod-shaped liquid crystal compounds or discotic liquid crystal compounds (disc-shaped liquid crystal compounds) are preferred. In addition, monomeric liquid crystal compounds or relatively low-molecular-weight liquid crystal compounds with a degree of polymerization of less than 100 are preferred.

[0024] Liquid crystal compounds preferably have polymerizable groups. In other words, liquid crystal compounds are preferably polymerizable liquid crystal compounds. Examples of polymerizable groups in polymerizable liquid crystal compounds include acryloyl groups, methacryloyl groups, epoxy groups, and vinyl groups. By polymerizing such polymerizable liquid crystal compounds, the orientation of the liquid crystal compound can be fixed. Furthermore, after the liquid crystal compound has been fixed by polymerization, it no longer needs to exhibit liquid crystalline properties.

[0025] Examples of rod-shaped liquid crystal compounds include claim 1 of Japanese Patent Publication No. 11-513019 or paragraph of Japanese Patent Application Publication No. 2005-289980.

[0026] The products described in paragraph

[0098] are preferred, and as discotic liquid crystal compounds, for example, those described in paragraphs

[0020] to

[0067] of Japanese Patent Application Publication No. 2007-108732 or paragraphs

[0013] to

[0108] of Japanese Patent Application Publication No. 2010-244038 are preferred. Alternatively, a liquid crystal compound exhibiting inverse wavelength dispersion may be used as the liquid crystal compound.

[0026] Possible orientation states for liquid crystal compounds include, for example, homogeneous orientation, homeotropic orientation, hybrid orientation, torsional orientation, and skewed orientation. The torsional orientation, in particular, refers to an orientation state in which the liquid crystal compound is twisted from one main surface to the other of the optically anisotropic layer, with the thickness direction of the optically anisotropic layer as the axis of rotation. In torsional orientation, the twist angle of the liquid crystal compound (the twist angle in the orientation direction of the liquid crystal compound) is usually greater than 0° and less than or equal to 360°.

[0027] At least one of the first to fourth optical anisotropic layers may be an A plate, a negative A plate, or a positive A plate. The in-plane retardation of the negative A plate at a wavelength of 550 nm is not particularly limited, but 70 to 200 nm is preferred, and 80 to 190 nm is more preferred, in terms of the performance of the circular polarizer containing the laminated film of the present invention. The retardation in the thickness direction of the negative A plate at a wavelength of 550 nm is not particularly limited, but -100 to -35 nm is preferred, and -95 to -40 nm is more preferred, in that the circular polarizer plate containing the laminated film of the present invention exhibits superior performance. The in-plane retardation of the above-mentioned positive A plate at a wavelength of 550 nm is not particularly limited, but 40 to 280 nm is preferred, and 60 to 150 nm is more preferred, in terms of the superior performance of the circular polarizer containing the laminated film of the present invention. The retardation in the thickness direction of the positive A plate at a wavelength of 550 nm is not particularly limited, but 20 to 140 nm is preferred, and 30 to 75 nm is more preferred, in that the circular polarizer plate containing the laminated film of the present invention exhibits superior performance.

[0028] Furthermore, at least one of the first to fourth optical anisotropic layers may be a C plate, a negative C plate, or a positive C plate. The in-plane retardation of the above-mentioned negative C plate at a wavelength of 550 nm is preferably 0 to 10 nm. The retardation in the thickness direction of the negative C plate at a wavelength of 550 nm is not particularly limited, but 10 to 120 nm is preferred, and 15 to 60 nm is more preferred, in that the circular polarizer plate containing the laminated film of the present invention exhibits superior performance. The in-plane retardation of the above-mentioned positive C plate at a wavelength of 550 nm is preferably 0 to 10 nm. The retardation in the thickness direction of the positive C plate at a wavelength of 550 nm is not particularly limited, but -120 to -10 nm is preferred, and -100 to -30 nm is more preferred, in that the circular polarizer plate containing the laminated film of the present invention exhibits superior performance.

[0029] Furthermore, at least one of the first to fourth optical anisotropic layers may be a layer in which a torsion-oriented liquid crystal compound is fixed (a layer in which a torsion-oriented liquid crystal compound is fixed along a helical axis extending in the thickness direction). The liquid crystal compound used in the layer formed by fixing a twisted-oriented liquid crystal compound is preferably a rod-shaped liquid crystal compound. The torsion angle of the liquid crystal compound is preferably in the range of 10 to 180°, and more preferably in the range of 30 to 90°, in terms of achieving superior performance of the circular polarizer containing the laminated film of the present invention. The value of the product Δnd, which is the refractive index anisotropy Δn of the layer in which the torsion-oriented liquid crystal compound is fixed at a wavelength of 550 nm and the thickness d of the layer in which the torsion-oriented liquid crystal compound is fixed, is not particularly limited. However, 40 to 280 nm is preferred, and 100 to 200 nm is more preferred, in terms of the superior performance of the circular polarizer containing the laminated film of the present invention. The above-mentioned torsional angle and Δnd are measured using Axometrics' AxoScan (polarimeter) device and their device analysis software.

[0030] The thickness of each of the first to fourth optical anisotropic layers is not particularly limited, but is preferably 10 μm or less, more preferably 0.1 to 5.0 μm, and even more preferably 0.3 to 3.0 μm. Note that the thickness of each layer from the first optical anisotropy layer to the fourth optical anisotropy layer refers to the average thickness of each layer. The above average thickness is obtained by measuring the thickness of any five or more points in each layer and taking the arithmetic mean of them.

[0031] One preferred configuration of the first to fourth optical anisotropic layers is one in which the first optical anisotropic layer is a negative C plate, the second optical anisotropic layer is a negative A plate, the third optical anisotropic layer is a layer on which a torsion-oriented liquid crystal compound is fixed, and the fourth optical anisotropic layer is a positive C plate. In the above embodiment, it is preferable that the angle between the in-plane slow axis on the surface of the second optical anisotropy layer facing the third optical anisotropy layer and the in-plane slow axis on the surface of the third optical anisotropy layer facing the second optical anisotropy layer is within the range of 0 to 30°.

[0032] <Close-up layer> The adhesion layer is a layer selected from the group consisting of an adhesive layer and a tack layer. The adhesive layer is a layer formed using an adhesive. Examples of adhesives include water-based adhesives, solvent-based adhesives, emulsion-based adhesives, solvent-free adhesives, active energy ray-curing adhesives, and thermosetting adhesives. Examples of active energy ray-curing adhesives include electron beam-curing adhesives, ultraviolet-curing adhesives, and visible light-curing adhesives, with ultraviolet-curing adhesives being preferred. In other words, the adhesion layer is preferably a layer formed using an ultraviolet-curing adhesive. Specific examples of active energy ray curing adhesives include (meth)acrylate adhesives. Examples of curing components in (meth)acrylate adhesives include compounds having a (meth)acryloyl group and compounds having a vinyl group.

[0033] The thickness of the adhesive layer is not particularly limited, but is preferably 0.1 to 5 μm, and more preferably 0.5 to 2 μm.

[0034] The adhesive layer is a layer formed using an adhesive. Examples of adhesives include rubber-based adhesives, acrylic-based adhesives, silicone-based adhesives, urethane-based adhesives, vinyl alkyl ether-based adhesives, polyvinyl alcohol-based adhesives, polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, and cellulose-based adhesives, with acrylic-based adhesives (pressure-sensitive adhesives) being preferred. As an acrylic adhesive, a copolymer of (meth)acrylate, in which the alkyl group of the ester portion is an alkyl group having 20 or fewer 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.

[0035] The thickness of the adhesive layer is not particularly limited, but is preferably 1 to 30 μm, and more preferably 5 to 20 μm.

[0036] The refractive index of the adhesion layer can be adjusted by known means to adjust the refractive index difference with the bonded object. For example, to increase the refractive index of the adhesion layer, it is preferable to use resins and monomers with a high refractive index, or metal nanoparticles. The resins and monomers with a high refractive index are not particularly limited as long as their refractive index is 1.50 or higher. Examples of metal nanoparticles include alumina particles, alumina hydrate particles, silica particles, zirconia particles, and inorganic particles such as clay minerals (e.g., smectite). The refractive index can be adjusted to a predetermined value by changing the amount of resins and monomers with a high refractive index, as well as metal nanoparticles.

[0037] <Other layers> The laminated film of the present invention may have layers other than the first to fourth optical anisotropic layers and the adhesion layer described above.

[0038] (Orientation film) The laminated film of the present invention may have an alignment layer. The alignment layer may be arranged between each optical anisotropic layer. However, from the viewpoint of reducing process-induced point defects, it is preferable to form a composition layer (optical anisotropic layer) having orientation control ability on the surface of the optical anisotropic layer without using an alignment layer, rather than using an alignment layer. The oriented film can be formed by means such as rubbing of an organic compound (preferably a polymer), oblique deposition of an inorganic compound, formation of a layer having microgrooves, or accumulation of an organic compound (e.g., ω-tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearylate) by the Langmuir-Bludget method (LB film). Furthermore, orientation films are known in which orientation functions are generated by the application of an electric field, a magnetic field, or light irradiation (preferably polarized light). The orientation film is preferably formed by a polymer rubbing treatment. Photo-alignment films can also be considered as alignment films. The thickness of the orientation film is not particularly limited as long as it can perform the orientation function, but it is preferably 0.01 to 5.0 μm, more preferably 0.05 to 3.0 μm, and even more preferably 0.5 to 1.0 μm.

[0039] (substrate) The laminated film of the present invention may have a substrate. However, from the viewpoint of making the laminated film of the present invention thinner, it is preferable that the laminated film does not have a substrate between each optical anisotropic layer. A transparent substrate is preferred as the substrate. A transparent substrate is defined as a substrate with a visible light transmittance of 60% or more, preferably 80% or more, and more preferably 90% or more. The thickness of the substrate is not particularly limited, but is preferably 10 to 200 μm, more preferably 10 to 100 μm, and even more preferably 20 to 90 μm.

[0040] Furthermore, the substrate may consist of multiple layers stacked together. To improve adhesion between the substrate and the layer placed on top of it, the substrate surface may be subjected to surface treatment (for example, glow discharge treatment, corona discharge treatment, ultraviolet (UV) treatment, flame treatment). Alternatively, an adhesive layer (primer layer) may be provided on the substrate. The substrate may be peelable from the laminated film.

[0041] (Other optically anisotropic layers) The laminated film of the present invention may have further optical anisotropic layers in addition to the first to fourth optical anisotropic layers described above.

[0042] <Characteristics of laminated films> The laminated film of the present invention has a minimum transmittance of 60% or more in the wavelength range of 400 to 700 nm, and exhibits excellent transparency. In particular, a transmittance of 75% or more is preferred, and a transmittance of over 90% is even more preferred for superior transparency. There is no particular upper limit, but it is often 99.9% or less. Furthermore, the minimum transmittance of the laminated film of the present invention in the wavelength range of 450 to 700 nm is not particularly limited as long as it satisfies the requirement for the minimum transmittance in the wavelength range of 400 to 700 nm. However, from the viewpoint of superior transparency of the laminated film, it is preferably 60% or more, more preferably 75% or more, and even more preferably over 90%. There is no particular upper limit, but it is often 99.9% or less. The minimum transmittance mentioned above is measured using a spectrophotometer (UV-3150, manufactured by Shimadzu Corporation).

[0043] The optical properties of the laminated film of the present invention are not particularly limited, but in terms of superior function as a circular polarizer, the in-plane retardation at a wavelength of 550 nm is preferably 100 to 180 nm, and more preferably 130 to 150 nm. The retardation in the thickness direction of the laminated film at a wavelength of 550 nm is not particularly limited, but -100 to 100 nm is preferred, and -30 to 30 nm is more preferred, as it provides superior functionality as a circular polarizer.

[0044] The thickness of the laminated film of the present invention is not particularly limited, and is often 100 μm or less. From the viewpoint of thinning, it is preferably 20 μm or less, and more preferably 10 μm. The lower limit is not particularly limited, but is often 5 μm or more. The thickness of the laminated film is determined by measuring the thickness of five or more arbitrary points on the laminated film and taking the arithmetic mean of those measurements. In other words, the above value is an average value. Furthermore, the thickness of the laminated film refers to the sum of the thicknesses of the components from the first optical anisotropy layer to the fourth optical anisotropy layer. For example, if the laminated film has first to fourth optical anisotropy layers, with the first and second optical anisotropy layers in direct contact, an adhesion layer placed between the second and third optical anisotropy layers, and the third and fourth optical anisotropy layers in direct contact, then the thickness of the laminated film refers to the sum of the thicknesses of the first to fourth optical anisotropy layers and the thickness of the adhesion layer. Furthermore, if the laminated film has additional optical anisotropy layers different from the first to fourth optical anisotropy layers, it refers to the sum of the thicknesses of the portions sandwiched between the optical anisotropy layers that are furthest apart from each other in the thickness direction. For example, if the laminated film has first to fifth optical anisotropy layers, and the first and second optical anisotropy layers are in direct contact, with an adhesion layer between the second and third optical anisotropy layers, and the third and fourth optical anisotropy layers are in direct contact, and the fourth and fifth optical anisotropy layers are in direct contact, then the thickness of the portion sandwiched between the first and fifth optical anisotropy layers, specifically the sum of the thicknesses of the first to fifth optical anisotropy layers and the thickness of the adhesion layer, corresponds to the thickness of the laminated film.

[0045] The laminated film is preferably one or two of requirements X1 to X3 in terms of having superior effects according to the present invention. Requirement X1: The first optical anisotropic layer and the second optical anisotropic layer are in direct contact or laminated via an alignment film, and the orientation direction of the liquid crystal compound on the surface of the first optical anisotropic layer facing the second optical anisotropic layer is different from the orientation direction of the liquid crystal compound on the surface of the second optical anisotropic layer facing the first optical anisotropic layer. Requirement X2: The second optical anisotropy layer and the third optical anisotropy layer are in direct contact or laminated via an alignment film, and the orientation direction of the liquid crystal compound on the surface of the second optical anisotropy layer facing the third optical anisotropy layer is different from the orientation direction of the liquid crystal compound on the surface of the third optical anisotropy layer facing the second optical anisotropy layer. Requirement X3: The third optical anisotropy layer and the fourth optical anisotropy layer are in direct contact or laminated via an alignment film, and the orientation direction of the liquid crystal compound on the surface of the third optical anisotropy layer facing the fourth optical anisotropy layer is different from the orientation direction of the liquid crystal compound on the surface of the fourth optical anisotropy layer facing the third optical anisotropy layer. As an example of cases where the orientation directions of the liquid crystal compounds differ, for instance, when an optically anisotropic layer with homogeneously oriented liquid crystal compounds fixed in place is in direct contact with an optically anisotropic layer with homeotropically oriented liquid crystal compounds fixed in place, the orientation directions of the two liquid crystal compounds will be different. In addition, in requirement X1, it is preferable that the first optical anisotropy layer and the second optical anisotropy layer are in direct contact; in requirement X2, it is preferable that the second optical anisotropy layer and the third optical anisotropy layer are in direct contact; and in requirement X3, it is preferable that the third optical anisotropy layer and the fourth optical anisotropy layer are in direct contact.

[0046] The laminated film is preferably one that satisfies any one of requirements Y1 to Y3 in that it further reduces reflected light. Requirement Y1: An adhesion layer is placed between the first optical anisotropy layer and the second optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the first optical anisotropy layer is 0.10 or less (preferably 0.05 or less), and the difference between the refractive index of the adhesion layer and the refractive index of the second optical anisotropy layer is 0.10 or less (preferably 0.05 or less). Requirement Y2: An adhesion layer is placed between the second optical anisotropy layer and the third optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the second optical anisotropy layer is 0.10 or less (preferably 0.05 or less), and the difference between the refractive index of the adhesion layer and the refractive index of the third optical anisotropy layer is 0.10 or less (preferably 0.05 or less). Requirement Y3: An adhesion layer is placed between the third optical anisotropy layer and the fourth optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the third optical anisotropy layer is 0.10 or less (preferably 0.05 or less), and the difference between the refractive index of the adhesion layer and the refractive index of the fourth optical anisotropy layer is 0.10 or less (preferably 0.05 or less).

[0047] One preferred embodiment of the laminated film of the present invention, in which the effects of the present invention are even better, is an embodiment in which the first optical anisotropy layer and the second optical anisotropy layer are in direct contact, there is an adhesion layer between the second optical anisotropy layer and the third optical anisotropy layer, and the third optical anisotropy layer and the fourth optical anisotropy layer are in direct contact.

[0048] <Method for manufacturing laminated film> The method for manufacturing the laminated film is not particularly limited, and known methods can be used. To form a state in which two optically anisotropic layers are in direct contact, for example, an optically anisotropic layer can be formed by applying an optically anisotropic layer-forming composition containing a liquid crystal compound having polymerizable groups (preferably containing a material that imparts orientation control ability to the surface of the optically anisotropic layer (e.g., a photo-alignment polymer) in the optically anisotropic layer-forming composition) to a substrate, and then applying another optically anisotropic layer-forming composition containing a liquid crystal compound having polymerizable groups on the formed optically anisotropic layer to form a separate optically anisotropic layer, thereby creating a state in which the two optically anisotropic layers are in direct contact. Furthermore, in order to form a state in which two optically anisotropic layers are arranged via an adhesion layer, for example, this state can be formed by bonding two separately prepared optically anisotropic layers via an adhesion layer. As described above, the laminated film of the present invention can be formed by combining a coating method using an optically anisotropic layer-forming composition containing a polymerizable liquid crystal compound and a lamination method.

[0049] The following describes, as an example, a method for manufacturing a laminated film in which the first optical anisotropy layer and the second optical anisotropy layer are in direct contact, there is an adhesion layer between the second optical anisotropy layer and the third optical anisotropy layer, and the third optical anisotropy layer and the fourth optical anisotropy layer are in direct contact. In manufacturing the above-mentioned laminated film, first, an optically anisotropic layer-forming composition (hereinafter also simply referred to as "optically anisotropic layer-forming composition") containing a liquid crystal compound having polymerizable groups is used to produce a first film comprising a first optically anisotropic layer and a second optically anisotropic layer in direct contact with each other, and a second film comprising a third optically anisotropic layer and a fourth optically anisotropic layer in direct contact with each other.

[0050] The polymerizable liquid crystal compound (hereinafter also referred to as "polymerizable liquid crystal compound") contained in the composition for forming an optically anisotropic layer is as described above. As described above, rod-shaped liquid crystal compounds and disc-shaped liquid crystal compounds are appropriately selected depending on the characteristics of the optically anisotropic layer formed. The content of polymerizable liquid crystal compounds in the optical anisotropic layer-forming composition is preferably 60 to 99% by mass, and more preferably 70 to 98% by mass, based on the total solid content of the optical anisotropic layer-forming composition. The term "solid content" refers to the components that can form an optically anisotropic layer after the solvent has been removed, and is considered solid content even if its state is liquid.

[0051] The composition for forming an optically anisotropic layer may contain compounds other than liquid crystal compounds having polymerizable groups. For example, in order to torsion-orient liquid crystal compounds, it is preferable that the optical anisotropy layer-forming composition contains a chiral agent. The chiral agent is added to torsion-orient the liquid crystal compound, but of course, if the liquid crystal compound is an optically active compound, such as having an asymmetric carbon in its molecule, the addition of a chiral agent is unnecessary. Furthermore, depending on the manufacturing method and the torsion angle, the addition of a chiral agent may not be necessary. As for the chiral agent, there are no particular structural restrictions as long as it is compatible with the liquid crystal compound used in combination. Any known chiral agent (for example, described in "Liquid Crystal Device Handbook" edited by the 142nd Committee of the Japan Society for the Promotion of Science, Chapter 3, Section 4-3, Chiral Agents for TN and STN, p. 199, 1989) can be used. The amount of chiral agent used is not particularly limited and is adjusted to achieve the aforementioned twist angle.

[0052] The composition for forming an optically anisotropic layer may contain a polymerization initiator. The polymerization initiator used is selected according to the type of polymerization reaction, and examples include thermal polymerization initiators and photopolymerization initiators. The content of the polymerization initiator in the optically anisotropic layer-forming composition is preferably 0.01 to 20% by mass, and more preferably 0.5 to 10% by mass, based on the total solid content of the optically anisotropic layer-forming composition.

[0053] Other components that may be included in the optically anisotropic layer-forming composition include, in addition to those mentioned above, polyfunctional monomers, orientation control agents (vertical orientation agents, horizontal orientation agents), surfactants, adhesion improvers, plasticizers, and solvents. Other components include photo-orienting compounds (e.g., photo-orienting polymers). Photo-orienting compounds are compounds that have photo-orienting groups, and these groups can be aligned in a predetermined direction upon light irradiation.

[0054] When preparing the first film, first, an optical anisotropy layer-forming composition is applied to the substrate, the formed coating is subjected to an orientation treatment to orient the polymerizable liquid crystal compound in the coating, and then a curing treatment is performed to form the first optical anisotropy layer. As described later, the substrate may be a removable temporary support. Methods for applying compositions for forming optically anisotropic layers include curtain coating, dip coating, spin coating, printing coating, spray coating, slot coating, roll coating, slide coating, blade coating, gravure coating, and wire bar coating.

[0055] Orientation treatment can be performed by drying the coating film at room temperature or by heating the coating film. In the case of thermotropic liquid crystal compounds, the liquid crystal phase formed by orientation treatment can generally be shifted by changes in temperature or pressure. In the case of lyotropic liquid crystal compounds, the phase can also be shifted by changes in the composition ratio, such as the amount of solvent. The conditions for heating the coating film are not particularly limited, but the heating temperature is preferably 50 to 250°C, more preferably 50 to 150°C, and the heating time is preferably 10 seconds to 10 minutes. Furthermore, after heating the coating film, it may be cooled as needed before the curing treatment (light irradiation treatment) described later.

[0056] The curing treatment method applied to a coating film on which polymerizable liquid crystal compounds are oriented is not particularly limited and includes, for example, light irradiation treatment and heat treatment. Among these, light irradiation treatment is preferred from the viewpoint of manufacturability, and ultraviolet irradiation treatment is more preferred. There are no particular restrictions on the irradiation conditions for the light irradiation treatment, but 50-1000 mJ / cm² is recommended. 2 A certain irradiation dose is preferred. The atmosphere during the light irradiation treatment is not particularly limited, but a nitrogen atmosphere is preferred.

[0057] Next, an optical anisotropy layer forming composition is applied to the formed first optical anisotropy layer, the formed coating film is subjected to an orientation treatment to orient the polymerizable liquid crystal compound in the coating film, and then a curing treatment is performed to form a second optical anisotropy layer. The procedure for forming the second optical anisotropy layer is the same as the procedure for forming the first optical anisotropy layer. The above process yields a first film comprising a first optical anisotropy layer and a second optical anisotropy layer, the two of which are in direct contact. Furthermore, before applying the optical anisotropy layer forming composition for forming the second optical anisotropy layer onto the first optical anisotropy layer, the surface of the first optical anisotropy layer may be rubbed if necessary. Also, if the photo-oriented polymer is unevenly distributed on the surface of the first optical anisotropy layer, the photo-oriented polymer on the surface of the first optical anisotropy layer may be oriented by light irradiation to impart an orientation-regulating force. A second film is obtained by following the same procedure as described above, which includes a third optical anisotropy layer and a fourth optical anisotropy layer, in which the two layers are in direct contact.

[0058] Next, the obtained first film and second film are laminated together with an adhesive layer in between. When an adhesive layer is used as the bonding layer, for example, the adhesive is applied to one surface of the first film, the surface with the adhesive applied is brought into contact with the second film to bond the first film and the second film, and if necessary, a curing treatment is performed to obtain the desired laminated film. If the adhesive is an ultraviolet-curing adhesive, the curing treatment may be ultraviolet irradiation treatment. Furthermore, when an adhesive layer is used as the bonding layer, for example, an adhesive is applied to one surface of the first film, and the surface with the adhesive applied is brought into contact with the second film to bond the first film and the second film together, thereby obtaining the desired laminated film. Furthermore, after bonding, the substrates contained in the first and second films may be peeled off if necessary.

[0059] Although the above describes a manufacturing method in which the first optical anisotropy layer and the second optical anisotropy layer are in direct contact, an alignment film may be placed between them.

[0060] <Circular polarizer> The laminated film of the present invention may be used as a circular polarizer in combination with a polarizer. A circular polarizer is an optical element that converts unpolarized light into circularly polarized light. The circular polarizing plate of the present invention having the above configuration is suitably used for anti-reflective applications in display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), electroluminescent displays (ELDs), and cathode ray tube displays (CRTs).

[0061] A polarizer can be any component that has the function of converting natural light into a specific linearly polarized light; for example, an absorptive polarizer can be used. There are no particular restrictions on the type of polarizer; commonly used polarizers can be used, such as iodine-based polarizers, dye-based polarizers utilizing dichroic substances, and polyene-based polarizers. Iodine-based and dye-based polarizers are generally manufactured by adsorbing iodine or a dichroic dye onto polyvinyl alcohol and then stretching the material. A protective film may be placed on one or both sides of the polarizer.

[0062] The arrangement relationship between the polarizer's absorption axis and the laminated film is not particularly limited, and the optimal arrangement is selected depending on the type of optical anisotropy layer contained in the laminated film. For example, if the first optically anisotropic layer in the laminated film is a negative C plate, the second optically anisotropic layer is a negative A plate, the third optically anisotropic layer is a layer in which a torsionally oriented liquid crystal compound is fixed, and the fourth optically anisotropic layer is a positive C plate, then the angle between the absorption axis of the polarizer and the in-plane slow axis of the negative A plate is preferably in the range of 45 to 135°.

[0063] The above circular polarizing plate may have other components besides the laminated film and polarizer of the present invention. The circular polarizer may have an adhesion layer between the laminated film and the polarizer of the present invention. Examples of adhesion layers include known adhesive layers and bonding layers. Furthermore, the circular polarizer may have a polymer film between the laminated film and the polarizer of the present invention, but it is preferable to omit the polymer film from the viewpoint of thinning. Examples of polymer films include cellulose acylate films.

[0064] The method for manufacturing the circular polarizer described above is not particularly limited and includes known methods. For example, one method involves bonding a polarizer and a laminated film with an adhesion layer in between.

[0065] <Display device> The laminated film and circular polarizer of the present invention can be suitably applied to display devices. The display device of the present invention comprises a display element and the laminated film or circular polarizing plate described above. When applying the laminated film of the present invention to a display device, it is preferable to apply it as a circular polarizing plate as described above. In this case, the circular polarizing plate is positioned on the viewing side, and within the circular polarizing plate, the polarizer is positioned on the viewing side. The display element is not particularly limited and examples include organic electroluminescent display elements and liquid crystal display elements. [Examples]

[0066] The features of the present invention will be further described below with reference to examples and comparative examples. The materials, amounts used, proportions, processing content, and processing procedures shown in the following examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted restrictively by the specific examples shown below.

[0067] <Example 1> (Preparation of cellulose acylate film) The following composition was placed in a mixing tank, stirred, and then heated at 90°C for 10 minutes. The resulting composition was then filtered through filter paper with an average pore size of 34 μm and a sintered metal filter with an average pore size of 10 μm to prepare a dope. The solid content concentration of the dope was 23.5% by mass, and the solvent of the dope was methylene chloride / methanol / butanol = 81 / 18 / 1 (by mass ratio).

[0068] ------------------------------------------------------------------ Cellulose acylate dope ------------------------------------------------------------------ Cellulose acylate (acetyl substitution degree 2.86, viscosity-average degree of polymerization 310) 100 parts by mass Sugar ester compound 1 (shown in formula (S4) below): 6.0 parts by mass Sugar ester compound 2 (shown in formula (S5) below): 2.0 parts by mass Silica particle dispersion (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 0.1 part by mass Solvent (methylene chloride / methanol / butanol) ------------------------------------------------------------------

[0069] [ka]

[0070] [ka]

[0071] The dope prepared as described above was cast using a drum film-forming machine. The dope was cast from the die onto a metal support cooled to 0°C, and then the resulting web (film) was peeled off. The drum was made of stainless steel (SUS).

[0072] After the casting process, the resulting web (film) was peeled from the drum and dried for 20 minutes in a tenter device at 30-40°C during film transport, with clips holding both ends of the web in place. Subsequently, the web was further dried by zone heating while being transported on a roll. The resulting web was then knurled and wound up. The resulting cellulose acylate film had a thickness of 40 μm.

[0073] (Formation of laminated film (1A)) An optically anisotropic layer-forming composition (1-1) containing a rod-shaped liquid crystal compound of the following composition was applied to the cellulose acylate film described above using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 116°C for 1 minute, and then irradiated with a 365 nm UV-LED at a dose of 150 mJ / cm² while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less at a temperature of 78°C. 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 115°C for 25 seconds to form an optical anisotropy layer (1-1) (corresponding to a negative C plate), which corresponds to the first optical anisotropy layer. The resulting optically anisotropic layer (1-1) was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) at room temperature, through a wire grid polarizer, at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a long film 1 was obtained in which the surface of the optically anisotropic layer (1-1) was given the ability to control orientation. The thickness of the formed optically anisotropic layer (1-1) was 0.9 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was 40 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 0°, confirming that it was oriented horizontally with respect to the film surface.

[0074] -------------------------------------------------- Composition for forming optically anisotropic layer (1-1) -------------------------------------------------- 1 / 4 parts by mass of the disc-shaped liquid crystal compound shown below The following disc-shaped liquid crystal compound 2: 1 part by mass The following disc-shaped liquid crystal compound 3: 95.0 parts by mass 12.0 parts by mass of the following polymerizable monomer 1 3.0 parts by mass of the polymerization initiator S-1 (oxime type) listed below The following photoacid generator D-1: 3.0 parts by mass 0.6 parts by mass of the following photo-oriented polymer A-1 Diisopropylethylamine 0.2 parts by mass o-Xylene 475 parts by mass --------------------------------------------------

[0075] Disc-shaped liquid crystal compound 1

[0076] [ka]

[0077] Disc-shaped liquid crystal compound 2

[0078] [ka]

[0079] Disc-shaped liquid crystal compound 3

[0080] [ka]

[0081] Polymerizable monomer 1

[0082] [ka]

[0083] Polymerization initiator S-1

[0084] [ka]

[0085] Photoacid Generator D-1

[0086] [ka]

[0087] Photo-orienting polymer A-1 (The letters within each repeating unit represent the content (mass%) of each repeating unit relative to the total number of repeating units; a and b were 53% by mass and 47% by mass, respectively. The weight-average molecular weight was 183,000.)

[0088] [ka]

[0089] While continuously conveying the long film 1 described above without winding it, an optically anisotropic layer-forming composition (1-2) containing a rod-shaped liquid crystal compound of the following composition was applied onto the optically anisotropic layer (1-1) using a Gieser coating machine, and heated with hot air at 95°C for 120 seconds. Subsequently, the resulting composition layer was irradiated with UV light (100 mJ / cm²) at 95°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (1-2) corresponding to the second optical anisotropy layer (corresponding to the negative A plate) was formed. The optically anisotropic layer (1-2) had a thickness of 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow axis direction of the optically anisotropic layer (1-2) was -14° when viewed from the optically anisotropic layer (1-2) side.

[0090] -------------------------------------------------- Composition for forming optically anisotropic layer (1-2) -------------------------------------------------- 180 parts by mass of the above-mentioned disc-shaped liquid crystal compound 20 parts by mass of the above-mentioned disc-shaped liquid crystal compound 2 The following orientation agent for the interface of the orientation film: 1.8 parts by mass 10.0 parts by mass of the polymerizable monomer 1 mentioned above. 5.0 parts by mass of the above polymerization initiator S-1 (oxime type) 0.1 parts by mass of the following fluorine-containing compound A 0.21 parts by mass of the following fluorine-containing compound B 0.06 parts by mass of the following fluorine-containing compound C The following defoaming agent: 1 2.1 parts by mass Methyl ethyl ketone 299 parts by mass --------------------------------------------------

[0091] Orientation film interface orientation agent 1

[0092] [ka]

[0093] Fluorine-containing compound A (In the formula below, a and b represent the content (mass%) of each repeating unit relative to the total repeating units, where a represents 90% by mass and b represents 10% by mass.)

[0094] [ka]

[0095] Fluorine-containing compound B (The numerical value in each repeating unit represents the content relative to the total number of repeating units.)

[0096] [ka]

[0097] Fluorine-containing compound C (The numerical value in each repeating unit represents the content relative to the total number of repeating units.)

[0098] [ka]

[0099] Antifoaming agent 1

[0100] [ka]

[0101] Following the above procedure, an optically anisotropic layer (1-1) and an optically anisotropic layer (1-2) were directly laminated onto a long cellulose acylate film to obtain a rolled laminated film (1A).

[0102] (Formation of laminated film (1B)) On the cellulose acylate film described in Example 1, an optical anisotropy layer-forming composition (1-4) containing a rod-shaped liquid crystal compound with the following composition was applied using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 60°C for 1 minute, and while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less, an irradiation dose of 100 mJ / cm² was applied using a 365 nm UV-LED. 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 120°C for 1 minute to form an optical anisotropy layer (1-4) corresponding to the fourth optical anisotropy layer (corresponding to the positive C plate). UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer is applied to the optical anisotropic layer (1-4) at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a long film 2 was obtained in which a composition layer having orientation control ability was formed on the surface. The thickness of the formed optically anisotropic layer (1-4) was 0.7 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the retardation Rth in the thickness direction at a wavelength of 550 nm was -85 nm. The average tilt angle of the rod-shaped liquid crystal compound in the direction of the long axis with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface.

[0103] -------------------------------------------------- Composition for forming optically anisotropic layer (1-4) -------------------------------------------------- 100 parts by mass of the following rod-shaped liquid crystal compound (A) Polymerizable monomer (A-400, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) 4.2 parts by mass 5.1 parts by mass of the polymerization initiator S-1 (oxime type) mentioned above. 3.0 parts by mass of the above photoacid generator D-1 5.1 parts by mass of the polymer M-1 below The following orientation agent for the interface of the orientation film: 1.9 parts by mass 0.8 parts by mass of the following photo-oriented polymer A-2 Diisopropylethylamine 0.2 parts by mass Methyl ethyl ketone 93.8 parts by mass Methyl isobutyl ketone 372.0 parts by mass --------------------------------------------------

[0104] Rod-shaped liquid crystal compound (A) (hereinafter, a mixture of compounds. The numerical values ​​represent the mass ratio.)

[0105] [ka]

[0106] Polymer M-1 (weight-average molecular weight was 60,000).

[0107] [ka]

[0108] Orientation film interface orientation agent 2

[0109] [ka]

[0110] Photo-oriented polymer A-2 (wherein a to c in the formula below, a:b:c = 17:64:19, indicating the content of each repeating unit relative to the total repeating units in the polymer. The weight-average molecular weight was 100,000.)

[0111] [ka]

[0112] While continuously conveying the long film 2 described above without winding it, an optical anisotropic layer-forming composition (1-3) containing a rod-shaped liquid crystal compound of the following composition was applied onto the optical anisotropic layer (1-4) using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the resulting composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropic layer (1-3) corresponding to the third optical anisotropic layer (corresponding to a layer in which a torsion-oriented liquid crystal compound is fixed) was formed. The optically anisotropic layer (1-3) had a thickness of 1.25 μm, a Δnd of 170 nm at a wavelength of 550 nm, and a torsion angle of 85° for the liquid crystal compound. When the film width direction is 0° (longitudinal direction is 90°), when viewed from the optically anisotropic layer (1-3) side, the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was 10° on the air side and 95° on the side in contact with the optically anisotropic layer (1-4). The in-plane slow-moving axis direction of the optical anisotropic layer is expressed by observing the substrate from the surface side of the optical anisotropic layer, with the substrate width direction being the reference 0°, and clockwise (rightward) rotation being negative and counterclockwise (leftward) rotation being positive.

[0113] -------------------------------------------------- Composition for forming optically anisotropic layer (1-3) -------------------------------------------------- 100 parts by mass of the above rod-shaped liquid crystal compound (A) Ethylene oxide-modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure 819, manufactured by BASF) 3 parts by mass The following left-handed chiral agent (L1): 0.60 parts by mass 0.08 parts by mass of the following fluorine-containing compound D Methyl ethyl ketone 156 parts by mass --------------------------------------------------

[0114] Left-handed chiral agent (L1)

[0115] [ka]

[0116] Fluorine-containing compound D (The numerical value in each repeating unit represents the content (mass %) relative to the total number of repeating units.)

[0117] [ka]

[0118] Following the procedure described above, a roll-shaped laminated film (1B) was prepared in which optically anisotropic layers (1-4) and optically anisotropic layers (1-3) were directly laminated onto a long cellulose acylate film.

[0119] (Preparation of laminated film (1)) The liquid crystal coated side of the laminated film (1A) made of the long cellulose acylate film prepared above, and the liquid crystal coated side of the laminated film (1B) formed on the long cellulose acylate film prepared above, were subjected to corona treatment, and then bonded together in a continuous machine using an ultraviolet-curable adhesive composition (1) of the following composition so that the longitudinal directions of the films were parallel. The refractive index of the adhesive layer formed from the UV-curing adhesive was 1.59, and the refractive indices of the adjacent optical anisotropy layers (1-2) and (1-3) were 1.59 and 1.57, respectively, with a refractive index difference of 0.05 or less from the adhesive layer. -------------------------------------------------- UV-curing adhesive composition (1) -------------------------------------------------- Arronix UVX-6282 (Toa Gosei Chemical) 20 parts by mass Lumiplus LPK-2000 (Mitsubishi Gas Chemical) 80 parts by mass --------------------------------------------------

[0120] Next, the cellulose acylate film on the laminated film (1A) side was peeled off, exposing the surface of the optically anisotropic layer (1-1) that had been in contact with the cellulose acylate film. In this way, a long laminated film (1) was obtained in which the optically anisotropic layer (1-1), optically anisotropic layer (1-2), adhesive layer, optically anisotropic layer (1-3), and optically anisotropic layer (1-4) were laminated in this order.

[0121] (Fabrication of linear polarizing plates) The surface of a cellulose triacetate film TJ25 (manufactured by Fujifilm Corporation: 25 μm thick) support was subjected to alkaline saponification treatment. Specifically, the support was immersed in a 1.5 N sodium hydroxide aqueous solution at 55°C for 2 minutes, then washed in a water bath at room temperature, and further neutralized with 0.1 N sulfuric acid at 30°C. After neutralization, the support was washed in a water bath at room temperature and further dried with hot air at 100°C to obtain a polarizer protective film. A 60 μm thick roll of polyvinyl alcohol (PVA) film was continuously stretched longitudinally in an iodine aqueous solution and dried to obtain a polarizer with a thickness of 13 μm. The luminous efficiency-corrected single-unit transmittance of the polarizer was 43%. At this time, the absorption axis direction and the longitudinal direction of the polarizer coincided. A linear polarizer was fabricated by attaching the polarizer protective film to one side of the polarizer using the PVA adhesive described below.

[0122] (Preparation of PVA adhesive) A PVA adhesive was prepared by dissolving 100 parts by mass of a polyvinyl alcohol-based resin having acetoacetyl groups (average degree of polymerization: 1200, degree of saponification: 98.5 mol, degree of acetoacetylation: 5 mol%) and 20 parts by mass of methylolmelamine in pure water at a temperature of 30°C, and adjusting the solid content concentration to 3.7% by mass to obtain an aqueous solution.

[0123] (Fabrication of circular polarizing plate (P1)) The surface of the optically anisotropic layer (1-1) of the long laminated film (1) prepared above and the surface of the polarizer of the long linear polarizing plate prepared above (the side opposite the polarizer protective film) were continuously bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation). Subsequently, the cellulose acylate film on the optically anisotropic layer (1-4) side was peeled off, exposing the surface of the optically anisotropic layer (1-4) that was in contact with the cellulose acylate film. In this manner, a circular polarizer (P1) consisting of a laminated film (1) and a linear polarizer was fabricated. At this time, the polarizer protective film, PVA adhesive, polarizer, adhesive, optical anisotropy layer (1-1), optical anisotropy layer (1-2), adhesive layer, optical anisotropy layer (1-3), and optical anisotropy layer (1-4) were laminated in this order, and the angle between the absorption axis of the polarizer and the in-plane slow axis of optical anisotropy layer (1-2) was 76°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of optical anisotropy layer (1-3) on the optical anisotropy layer (1-2) side was 10°, and the angle between this and the in-plane slow axis direction of optical anisotropy layer (1-2) was 4°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of optical anisotropy layer (1-3) on the optical anisotropy layer (1-4) side was 95°. The thickness of the circular polarizer (P1) was 49 μm.

[0124] <Example 2> A laminated film (2) and a circular polarizer (P2) were prepared in the same manner as in Example 1, except that UV-curable adhesive composition (2) was used instead of UV-curable adhesive composition (1). The refractive index of the adhesive layer was 1.51, and the refractive index difference between it and the adjacent optical anisotropic layers (1-2) and (1-3) was greater than 0.05. -------------------------------------------------- UV-curing adhesive composition (2) -------------------------------------------------- Arronix UVX-6282 (Toa Gosei Chemical) 80 parts by mass Lumiplus LPK-2000 (Mitsubishi Gas Chemical) 20 parts by mass --------------------------------------------------

[0125] <Example 3> Laminated film (3) and circular polarizer (P3) were fabricated in the same manner as in Example 1, except that laminated films (1A) and (1B) were bonded using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation) instead of an ultraviolet-curing adhesive. The refractive index of the adhesive layer was 1.48, and the refractive index difference between it and the adjacent optical anisotropic layers (1-2) and (1-3) was greater than 0.05. Furthermore, the refractive index difference between it and optical anisotropic layer (1-2) was greater than 0.10.

[0126] <Example 4> (Preparation of laminated film (4A)) The optically anisotropic layer (1-1) prepared by the method of Example 1 was wound up to obtain a roll-shaped laminated film (1A-1). Subsequently, while feeding out the laminated film (1A-1), corona treatment was performed on the surface of the optically anisotropic layer (1-1), and then the following photo-alignment film composition (4) was applied using a Gieser coating machine and dried at 80°C for 1 minute. Then, the obtained coating film was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer at a rate of 10 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a photo-alignment film was formed on the surface of the optically anisotropic layer (1-1). The thickness of the formed photo-alignment film was 0.2 μm.

[0127] -------------------------------------------------- Composition for photo alignment film (4) -------------------------------------------------- 5 parts by mass of the following photo-oriented polymer A-3 Cyclopentanone 95 parts by mass --------------------------------------------------

[0128] Photo-oriented polymer A-3 (Me represents a methyl group. Weight-average molecular weight: 30000)

[0129] [ka]

[0130] Subsequently, while continuously conveying the long film without winding it up, the composition (1-2) for forming an optically anisotropic layer described in Example 1 was applied onto the photo-alignment film using a kiss coater, and heated with warm air at 95°C for 120 seconds. Subsequently, UV irradiation (100 mJ / cm 2 ) was performed on the obtained composition layer at 95°C to fix the alignment of the liquid crystal compound, thereby forming an optically anisotropic layer (4-2) corresponding to the second optically anisotropic layer. The thickness of the optically anisotropic layer (4-2) was 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average tilt angle of the disk plane of the discotic liquid crystal compound with respect to the film plane was 90°, and it was confirmed that the compound was vertically aligned with respect to the film plane. When the width direction of the film was set to 0° (the longitudinal direction was 90° counterclockwise and -90° clockwise), the in-plane slow axis direction of the optically anisotropic layer (4-2) was -14° when viewed from the side of the optically anisotropic layer (1-1). By the above procedure, a laminated film (4A) was obtained in which an optically anisotropic layer (1-1), a photo-alignment film, and an optically anisotropic layer (4-2) were laminated in this order on a long cellulose acetate film and wound into a roll shape.

[0131] A laminated film (4) and a circularly polarized plate (P4) were produced in the same manner as in Example 1, except that the laminated film (4A) was used instead of the laminated film (1A).

[0132] <Example 5> (Production of laminated film (5B)) The optically anisotropic layer (1-4) produced by the method of Example 1 was wound up to obtain a roll-shaped laminated film (1B-1). Subsequently, while feeding out the laminated film (1B-1), corona treatment was performed on the surface of the optically anisotropic layer (1-4), and the composition (4) for a photo-alignment film described in Example 4 was applied using a kiss coater and dried at 80°C for 1 minute. Then, UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer was applied to the obtained coating film at 10 mJ / cm 2By irradiating with a wavelength of 313 nm, a photo-alignment film was formed on the surface of the optically anisotropic layer (1-4). The thickness of the formed photo-alignment film was 0.2 μm.

[0133] Next, while continuously conveying the long film without winding it, the optical anisotropy layer-forming composition (1-3) described in Example 1 was applied onto the photo-alignment film using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the resulting composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropic layer (5-3) corresponding to the third optical anisotropic layer was formed. The optically anisotropic layer (5-3) had a thickness of 1.25 μm, a Δnd of 170 nm at a wavelength of 550 nm, and a torsion angle of 85° of the liquid crystal compound. When the film width direction is 0° (longitudinal direction is 90°), when viewed from the optically anisotropic layer (5-3) side, the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was 10° on the air side and 95° on the side in contact with the optically anisotropic layer (1-4). The in-plane slow-moving axis direction of the optical anisotropic layer is expressed by observing the substrate from the surface side of the optical anisotropic layer, with the substrate width direction being the reference 0°, and clockwise (rightward) rotation being negative and counterclockwise (leftward) rotation being positive.

[0134] Following the above procedure, a laminated film (5B) was obtained by laminating optically anisotropic layers (1-4), a photo-alignment film, and an optically anisotropic layer (5-3) in that order on a long cellulose acylate film, and then winding it into a roll.

[0135] A laminated film (5) and a circular polarizing plate (P5) were fabricated in the same manner as in Example 1, except that a laminated film (5B) was used instead of a laminated film (1B).

[0136] <Example 6> While feeding out the roll-shaped laminated film (1A) prepared by the method of Example 1, corona treatment was performed on the surface of the optically anisotropic layer (1-2), and the photo-alignment film composition (4) described in Example 4 was applied using a Gieser coating machine and dried at 80°C for 1 minute. Then, the obtained coating film was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer at a rate of 10 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a photo-alignment film was formed on the surface of the optically anisotropic layer (1-2). The thickness of the formed photo-alignment film was 0.2 μm.

[0137] Next, while continuously conveying the long film without winding it, the optical anisotropy layer-forming composition (1-3) described in Example 1 was applied onto the photo-alignment film using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the resulting composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropic layer (6-3) corresponding to the third optical anisotropic layer was formed. The optically anisotropic layer (6-3) had a thickness of 1.25 μm, a Δnd of 170 nm at a wavelength of 550 nm, and a torsion angle of 85° of the liquid crystal compound. Assuming the film width direction is 0° (longitudinal direction is 90°), when viewed from the optically anisotropic layer (6-3) side, the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was -95° on the air side and -10° on the side in contact with the optically anisotropic layer (1-2). The in-plane slow axis direction on the surface side of the optically anisotropic layer (6-3) was -4° relative to the in-plane slow axis direction on the surface side of the optically anisotropic layer (1-2).

[0138] Following the above procedure, optically anisotropic layers (1-1), (1-2), and (6-3) were laminated in this order on a long cellulose acylate film to obtain a rolled laminated film (6A).

[0139] Laminated film (6) and circular polarizer (P6) were fabricated in the same manner as in Example 1, except that laminated film (6A) was used instead of laminated film (1A), and laminated film (1B-1) prepared by the method of Example 5 was used instead of laminated film (1B). The refractive indices of the adhesive layer and the adjacent optical anisotropic layers (6-3) and (1-4) were 1.57 and 1.57, respectively, and the refractive index difference with the adhesive layer was 0.05 or less.

[0140] <Example 7> While feeding out the roll-shaped laminated film (1B) prepared by the method of Example 1, corona treatment was performed on the surface of the optically anisotropic layer (1-3), and the photo-alignment film composition (4) described in Example 4 was applied using a Gieser coating machine and dried at 80°C for 1 minute. Then, the obtained coating film was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer at a rate of 10 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a photo-alignment film was formed on the surface of the optically anisotropic layer (1-3). The thickness of the formed photo-alignment film was 0.2 μm. Next, while continuously conveying the long film without winding it, the optical anisotropy layer-forming composition (1-2) described in Example 1 was applied to the photo-alignment film provided on the laminated film (1B) using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the obtained composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (7-2) corresponding to the second optical anisotropy layer was formed. The optically anisotropic layer (7-2) had a thickness of 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow axis direction of the optically anisotropic layer (7-2) was +14° when viewed from the optically anisotropic layer (7-2) side.

[0141] Following the above procedure, optically anisotropic layers (1-4), (1-3), and (7-2) were laminated in this order on a long cellulose acylate film to obtain a rolled laminated film (7B).

[0142] A laminated film (7) and a circular polarizing plate (P7) were fabricated in the same manner as in Example 1, except that a laminated film (1A-1) prepared by the method of Example 4 was used instead of laminated film (1A), and the above-mentioned laminated film (7B) was used instead of laminated film (1B). The refractive indices of the adhesive layer and the adjacent optical anisotropic layers (1-1) and (7-2) were 1.60 and 1.59, respectively, and the refractive index difference with the adhesive was 0.05 or less.

[0143] <Example 8> (Formation of laminated film (8A)) An optically anisotropic layer-forming composition (8-1) containing a rod-shaped liquid crystal compound of the following composition was applied to a long cellulose acetate film ZRG20 (manufactured by Fujifilm Corporation: thickness 20 μm) using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 116°C for 1 minute, and then irradiated with a 365 nm UV-LED at a UV temperature of 78°C with an irradiation dose of 150 mJ / cm² while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less. 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 115°C for 25 seconds to form an optical anisotropic layer (8-1) corresponding to the first optical anisotropic layer. The resulting optically anisotropic layer (8-1) was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) at room temperature through a wire grid polarizer at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a composition layer with orientation control capabilities was formed on the surface. The thickness of the formed optically anisotropic layer (8-1) was 0.9 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was 40 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 0°, confirming that it was oriented horizontally with respect to the film surface.

[0144] -------------------------------------------------- Composition for forming optically anisotropic layer (8-1) -------------------------------------------------- 1.4 parts by mass of the above-mentioned disc-shaped liquid crystal compound 1 part by mass of the above-mentioned disc-shaped liquid crystal compound 2 The above-mentioned disc-shaped liquid crystal compound 3: 95.0 parts by mass 12.0 parts by mass of the polymerizable monomer 1 mentioned above. 3.0 parts by mass of the polymerization initiator S-1 (oxime type) mentioned above 3.0 parts by mass of the above photoacid generator D-1 0.6 parts by mass of the above-mentioned photo-oriented polymer A-1 Diisopropylethylamine 0.2 parts by mass Methyl isobutyl ketone 380 parts by mass 95 parts by mass of ethyl propionate --------------------------------------------------

[0145] While continuously conveying the above-mentioned long film without winding it, the optical anisotropic layer-forming composition (1-2) described in Example 1 was applied onto the optical anisotropic layer (8-1) using a Gieser coating machine, and heated with 95°C hot air for 120 seconds. Subsequently, the obtained composition layer was irradiated with UV light (100 mJ / cm²) at 95°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (8-2) corresponding to the second optical anisotropy layer was formed. The optically anisotropic layer (8-2) had a thickness of 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average tilt angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow axis direction of the optically anisotropic layer (8-2) was -14° when viewed from the optically anisotropic layer (8-2) side. By following the above procedure, an optically anisotropic layer (8-1) and an optically anisotropic layer (8-2) were directly laminated onto a long cellulose acylate film ZRG20 to obtain a rolled laminated film (8A).

[0146] (Preparation of laminated film (8)) The liquid crystal coated side of the laminated film (8A) made of the long cellulose acylate film prepared above and the liquid crystal coated side of the laminated film (1B) described in Example 1 were bonded together using an ultraviolet-curable adhesive composition (1) in a continuous machine so that the longitudinal directions of the films were parallel. The in-plane slow axis on the surface side of the optical anisotropy layer (1-3) of the laminated film (1B) is +4° relative to the in-plane slow axis on the surface side of the optical anisotropy layer (8-2) of the laminated film (8A). In this way, a long laminated film (8) was obtained in which the cellulose acylate film ZRG20, optical anisotropy layer (8-1), optical anisotropy layer (8-2), adhesive layer, optical anisotropy layer (1-3), and optical anisotropy layer (1-4) were laminated in this order.

[0147] (Fabrication of circular polarizer (P8)) The surface of the cellulose acylate film ZRG20 of the long laminated film (8) prepared above and the surface of the polarizer of the rectangular linear polarizer described in Example 1 (the side opposite the polarizer protective film) were continuously bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation). Subsequently, the cellulose acylate film on the optical anisotropy layer (1-4) side was peeled off, exposing the surface of the optical anisotropy layer (1-4) that had been in contact with the cellulose acylate film. In this manner, a circular polarizer (P8) consisting of a laminated film (8) and a linear polarizer was fabricated. At this time, the polarizer protective film, PVA adhesive, polarizer, adhesive, cellulose acylate film ZRG20, optical anisotropy layer (8-1), optical anisotropy layer (8-2), adhesive layer, optical anisotropy layer (1-3), and optical anisotropy layer (1-4) were laminated in this order, and the angle between the absorption axis of the polarizer and the in-plane slow axis of optical anisotropy layer (8-2) was 76°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction of optical anisotropy layer (1-3) on the surface facing optical anisotropy layer (8-2) was 14°, and the angle between it and the in-plane slow axis direction of optical anisotropy layer (8-2) was 4°. Furthermore, with the width direction set as the reference 0°, the in-plane slow phase axis direction on the surface of the optically anisotropic layer (1-3) on the optically anisotropic layer (1-4) side was 95°.

[0148] <Example 9> (Formation of laminated film (9A)) A composition layer was formed on the cellulose acylate film described in Example 1 by applying the optical anisotropy layer-forming composition (1-1) described in Example 1 using a Gieser coating machine. The film with the composition layer formed was heated with hot air at 116°C for 1 minute, and then irradiated with a 365 nm UV-LED at a UV temperature of 78°C with an irradiation dose of 150 mJ / cm² while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less. 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 115°C for 25 seconds to form an optical anisotropic layer (9-1) corresponding to the first optical anisotropic layer. The resulting optically anisotropic layer (9-1) was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) at room temperature through a wire grid polarizer at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a composition layer with orientation control capabilities was formed on the surface. The thickness of the formed optically anisotropic layer (9-1) was 0.7 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was 30 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 0°, confirming that it was oriented horizontally with respect to the film surface.

[0149] While continuously conveying the above-mentioned long film without winding it, the optical anisotropic layer-forming composition (1-2) described in Example 1 was applied onto the optical anisotropic layer (9-1) using a Gieser coating machine, and heated with 95°C hot air for 120 seconds. Subsequently, the obtained composition layer was irradiated with UV light (100 mJ / cm²) at 95°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropic layer (9-2) corresponding to the second optical anisotropic layer was formed. The optically anisotropic layer (9-2) had a thickness of 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow phase axis direction of the optically anisotropic layer (9-2) was -14° when viewed from the optically anisotropic layer (9-2) side.

[0150] By following the above procedure, an optically anisotropic layer (9-1) and an optically anisotropic layer (9-2) were directly laminated onto a long cellulose acylate film to obtain a laminated film (9A) wound into a roll.

[0151] (Formation of laminated film (9B)) On the cellulose acylate film described in Example 1, an optical anisotropy layer-forming composition (1-4) containing a rod-shaped liquid crystal compound with the following composition was applied using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 60°C for 1 minute, and while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less, an irradiation dose of 100 mJ / cm² was applied using a 365 nm UV-LED.2 It was irradiated with ultraviolet rays. Then, the obtained coating film was annealed at 120 °C for 1 minute with warm air to form an optically anisotropic layer (9-5) corresponding to the fifth optically anisotropic layer. While continuously conveying the long film without winding it up, UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) passed through a wire grid polarizer was applied to the optically anisotropic layer (9-5) at 7.9 mJ / cm 2 (wavelength: 313 nm) to form a composition layer having an orientation control ability on the surface. The film thickness of the formed optically anisotropic layer (9-5) was 0.7 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the retardation Rth in the thickness direction at a wavelength of 550 nm was -90 nm. The average inclination angle of the long axis direction of the rod-like liquid crystal compound with respect to the film surface was 90°, and it was confirmed that the liquid crystal compound was oriented perpendicular to the film surface.

[0152] While continuously conveying the long film without winding it up, using a kiss coater, the composition for forming an optically anisotropic layer (1-3) described in Example 1 was applied onto the optically anisotropic layer (9-5) and heated with warm air at 80 °C for 60 seconds. Subsequently, UV irradiation (500 mJ / cm 2 ) was performed on the obtained composition layer to fix the orientation of the liquid crystal compound and form an optically anisotropic layer (9-4) corresponding to the fourth optically anisotropic layer. The thickness of the optically anisotropic layer (9-4) was 1.25 μm, Δnd at a wavelength of 550 nm was 170 nm, and the twist angle of the liquid crystal compound was 85°. When the width direction of the film was 0° (the longitudinal direction was 90°), when viewed from the side of the optically anisotropic layer (9-4), the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was 10° on the air side and 95° on the side in contact with the optically anisotropic layer (9-5). The in-plane slow axis direction of the optically anisotropic layer is represented with the width direction of the substrate as the reference 0°, observing the substrate from the surface side of the optically anisotropic layer, with clockwise (rightward) being negative and counterclockwise (leftward) being positive.

[0153] After winding up the above-mentioned long film into a roll, it was sent out again. After corona treatment was carried out on the optical anisotropic layer (9-4), the following composition for forming an optical anisotropic layer (9-3) was applied using a kiss coater and heated with warm air at 80°C for 60 seconds. Subsequently, UV irradiation (500 mJ / cm 2 ) was performed on the obtained composition layer at 80°C to fix the alignment of the liquid crystal compound, thereby forming an optical anisotropic layer (9-3) corresponding to the third optical anisotropic layer. ―――――――――――――――――――――――――――――――― Composition for forming an optical anisotropic layer (9-3) ―――――――――――――――――――――――――――――――― 20.0 parts by mass of the above-mentioned rod-like liquid crystal compound (A) 4.2 parts by mass of a polymerizable monomer (A-400, manufactured by Shin-Nakamura Chemical Co., Ltd.) 5.1 parts by mass of the above-mentioned polymerization initiator S-1 (oxime type) 3.0 parts by mass of the above-mentioned photoacid generator D-1 2.0 parts by mass of the above-mentioned polymer M-1 2.0 parts by mass of the above-mentioned vertical alignment agent S01 0.4 parts by mass of the above-mentioned fluorine-containing compound A 2.0 parts by mass of diisopropylethylamine 42.3 parts by mass of methyl ethyl ketone 627.5 parts by mass of methyl isobutyl ketone ――――――――――――――――――――――――――――――――

[0154] The film thickness of the formed optical anisotropic layer (9-3) was 0.05 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was -5 nm. The average tilt angle of the long axis direction of the rod-like liquid crystal compound with respect to the film surface was 90°, and it was confirmed that the compound was vertically aligned with respect to the film surface.

[0155] Following the above procedure, optically anisotropic layers (9-5), (9-4), and (9-3) were directly laminated onto a long cellulose acylate film to obtain a laminated film (9B) wound into a roll.

[0156] (Preparation of laminated film (9)) A long laminated film (9) was obtained in the same manner as in Example 1, except that laminated films (9A) and (9B) were used instead of laminated films (1A) and (1B), and optical anisotropy layers (9-1), (9-2), (9-3), (9-4), and (9-5) were laminated in this order.

[0157] (Fabrication of circular polarizer (P9)) The surface of the optically anisotropic layer (9-1) of the long laminated film (9) prepared above and the surface of the polarizer of the long linear polarizing plate prepared above (the side opposite the polarizer protective film) were continuously bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation). Subsequently, the cellulose acylate film on the optically anisotropic layer (9-5) side was peeled off, exposing the surface of the optically anisotropic layer (9-5) that was in contact with the cellulose acylate film. In this manner, a circular polarizer (P9) consisting of a laminated film (9) and a linear polarizer was fabricated. At this time, the polarizer protective film, polarizer, optical anisotropy layer (9-1), optical anisotropy layer (9-2), optical anisotropy layer (9-3), optical anisotropy layer (9-4), and optical anisotropy layer (9-5) were laminated in this order, and the angle between the absorption axis of the polarizer and the in-plane slow axis of optical anisotropy layer (9-2) was 76°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction of optical anisotropy layer (9-4) on the surface facing optical anisotropy layer (9-3) was 10°, and the angle between this and the in-plane slow axis direction of optical anisotropy layer (9-2) was 4°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction of optical anisotropy layer (9-4) on the surface facing optical anisotropy layer (9-5) was 95°.

[0158] <Example 10> (Preparation of laminated film (10A)) On the cellulose acylate film prepared in Example 1, the optical anisotropy layer-forming composition (1-4) described in Example 1 was applied using a Gieser coating machine to form a composition layer. The resulting film was heated with hot air at 60°C for 1 minute, and while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less, it was irradiated with a 365 nm UV-LED at a dose of 100 mJ / cm². 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 120°C for 1 minute to form an optical anisotropic layer (10-1) corresponding to the first optical anisotropic layer. The resulting optically anisotropic layer (10⁻¹) was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) at room temperature, through a wire grid polarizer, at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a composition layer with orientation control capabilities was formed on the surface. The thickness of the formed optically anisotropic layer (10-1) was 0.49 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the retardation Rth in the thickness direction at a wavelength of 550 nm was -55 nm. The average tilt angle of the rod-shaped liquid crystal compound with respect to the film surface in the direction of the long axis was 90°, confirming that it was oriented perpendicular to the film surface.

[0159] Next, an optically anisotropic layer-forming composition (10-2) containing a rod-shaped liquid crystal compound of the following composition was applied onto the optically anisotropic layer (10-1) prepared above using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the resulting composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropic layer (10-2) corresponding to the second optical anisotropic layer was formed. The thickness of the optically anisotropic layer (10⁻²) was 0.53 μm, and the in-plane retardation Re(550) at a wavelength of 550 nm was 75 nm. When the width direction of the film was set to 0° (the longitudinal direction to 90°), the in-plane slow phase axis direction (orientation axis angle of the liquid crystal compound) was 90°.

[0160] -------------------------------------------------- Composition for forming optically anisotropic layer (10-2) -------------------------------------------------- 100 parts by mass of the above rod-shaped liquid crystal compound (A) Ethylene oxide-modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure 819, manufactured by BASF) 3 parts by mass 0.08 parts by mass of the above fluorine-containing compound C Methyl ethyl ketone 156 parts by mass --------------------------------------------------

[0161] Following the procedure described above, a laminated film (10A) was prepared in which an optically anisotropic layer (10-1) and an optically anisotropic layer (10-2) were directly laminated onto a long cellulose acylate film.

[0162] (Preparation of laminated film (10B)) On the cellulose acylate film prepared in Example 1, the optical anisotropy layer-forming composition (1-4) described in Example 1 was applied using a Gieser coating machine to form a composition layer. The resulting film was heated with hot air at 60°C for 1 minute, and while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less, it was irradiated with a 365 nm UV-LED at a dose of 100 mJ / cm². 2 The surface was irradiated with ultraviolet light. Subsequently, the resulting coating was annealed with hot air at 120°C for 1 minute to form an optical anisotropic layer (10-4) corresponding to the fourth optical anisotropy layer. The resulting optically anisotropic layer (10⁻⁴) was exposed to UV light (ultra-high pressure mercury lamp; UL750; manufactured by HOYA) at room temperature, through a wire grid polarizer, at a rate of 7.9 mJ / cm². 2 By irradiating with a wavelength of 313 nm, a composition layer with orientation control capabilities was formed on the surface. The film thickness of the formed optically anisotropic layer (10-4) was 0.35 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the retardation Rth in the thickness direction at a wavelength of 550 nm was -40 nm. The average tilt angle of the long axis direction of the rod-like liquid crystal compound with respect to the film plane was 90°, and it was confirmed that the compound was vertically aligned with respect to the film plane.

[0163] Next, an optically anisotropic layer forming composition (10-3) containing a rod-like liquid crystal compound with the following composition was applied onto the optically anisotropic layer (10-4) prepared above using a kiss coater. After being once heated to 120 °C with warm air, it was cooled to 60 °C to stabilize the alignment. Then, under a nitrogen atmosphere (oxygen concentration less than 100 ppm) using an ultra-high pressure mercury lamp, while maintaining the film temperature at 60 °C, after the first ultraviolet irradiation (80 mJ / cm 2 ), while maintaining the film temperature at 100 °C, the alignment was fixed by the second ultraviolet irradiation (300 mJ / cm 2 ), and an optically anisotropic layer (10-3) corresponding to the third optically anisotropic layer was formed. The thickness of the optically anisotropic layer (10-3) was 2.8 μm, and Re(550) at a wavelength of 550 nm was 141 nm. Assuming that the width direction of the film was 0° (the longitudinal direction was 90°), the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was 45°.

[0164] ―――――――――――――――――――――――――――――――― Optically anisotropic layer forming composition (10-3) ―――――――――――――――――――――――――――――――― 21.2 parts by mass of the following rod-like liquid crystal compound (B) 26.1 parts by mass of the following rod-like liquid crystal compound (C) 29.0 parts by mass of the following rod-like liquid crystal compound (D) 8.5 parts by mass of the following rod-like liquid crystal compound (E) 15.3 parts by mass of the following compound (1) 0.5 parts by mass of the above polymerization initiator S-1 (oxime type) 0.1 parts by mass of the following fluorine-containing compound D Cyclopentanone 175.0 parts by mass Methyl ethyl ketone 50.0 parts by mass Ethyl laurate 10.0 parts by mass --------------------------------------------------

[0165] Rod-shaped liquid crystal compound (B)

[0166] [ka]

[0167] Rod-shaped liquid crystal compound (C)

[0168] [ka]

[0169] Rod-shaped liquid crystal compound (D)

[0170] [ka]

[0171] Rod-shaped liquid crystal compound (E)

[0172] [ka]

[0173] Compound (1)

[0174] [ka]

[0175] Fluorine-containing compound D

[0176] [ka]

[0177] Following the procedure described above, a laminated film (10B) was prepared in which an optically anisotropic layer (10-4) and an optically anisotropic layer (10-3) were directly laminated onto a long cellulose acylate film.

[0178] A laminated film (10) and a circular polarizing plate (P10) were fabricated in the same manner as in Example 1, except that a laminated film (10A) was used instead of laminated film (1A), and the above-mentioned laminated film (10B) was used instead of laminated film (1B).

[0179] <Comparative Example 1> (Preparation of laminated film (C1A)) An optically anisotropic layer-forming composition (C1-1) containing a rod-shaped liquid crystal compound of the following composition was applied to the cellulose acylate film described in Example 1 using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 116°C for 1 minute, and then irradiated with UV light (500 mJ / cm²) at a UV temperature of 78°C while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (C1-1) corresponding to the first optical anisotropy layer was formed. The thickness of the formed optically anisotropic layer (C1-1) was 0.9 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was 40 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 0°, confirming that it was oriented horizontally with respect to the film surface.

[0180] -------------------------------------------------- Composition for forming optically anisotropic layers (C1-1) -------------------------------------------------- 1.4 parts by mass of the above-mentioned disc-shaped liquid crystal compound 1 part by mass of the above-mentioned disc-shaped liquid crystal compound 2 The above-mentioned disc-shaped liquid crystal compound 3: 95.0 parts by mass 12.0 parts by mass of the polymerizable monomer 1 mentioned above. 3.0 parts by mass of the polymerization initiator S-1 (oxime type) mentioned above 3.0 parts by mass of the above photoacid generator D-1 0.6 parts by mass of the above fluorine-containing compound E Diisopropylethylamine 0.2 parts by mass o-Xylene 475 parts by mass --------------------------------------------------

[0181] Following the above procedure, an optically anisotropic layer (C1-1) was laminated onto a long cellulose acylate film, and a rolled laminated film (C1A) was obtained.

[0182] (Fabrication of alignment film (10)) A photo-alignment film was formed by applying the following alignment film composition (10) onto the cellulose acylate film described in Example 1 using a Gieser coating machine. The cellulose acylate film on which the photo-alignment film was formed was dried with hot air at 140°C for 120 seconds, followed by irradiation with polarized ultraviolet light (10 mJ / cm²). 2 An alignment film (10) was formed by using an ultra-high pressure mercury lamp. ─────────────────────────────────── Alignment film composition (10) ─────────────────────────────────── 100.00 parts by mass of the following photo-oriented polymer A-4 Isopropyl alcohol 16.50 parts by mass Butyl acetate 1072.00 parts by mass Methyl ethyl ketone 268.00 parts by mass ───────────────────────────────────

[0183] Photo-orienting polymer A-4

[0184] [ka]

[0185] (Fabrication of laminated film (C1B)) While continuously conveying the long film having the alignment film (10) described above without winding, the optical anisotropy layer forming composition (1-2) described in Example 1 was applied using a Gieser coating machine, and heated with hot air at 95°C for 120 seconds. Subsequently, the obtained composition layer was irradiated with UV light (100 mJ / cm²) at 95°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (C1-2) corresponding to the second optical anisotropy layer was formed. The optically anisotropic layer (C1-2) had a thickness of 1.5 μm, and the in-plane retardation at a wavelength of 550 nm was 153 nm. The average tilt angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow phase axis direction of the optically anisotropic layer (C1-2) was +14° when viewed from the optically anisotropic layer (C1-2) side. Following the above procedure, an alignment film (10) and an optically anisotropic layer (C1-2) were laminated onto a long cellulose acylate film, and a rolled laminated film (C1B) was obtained.

[0186] (Fabrication of laminated film (C1C)) While continuously conveying the long film having the alignment film (10) described above without winding, the optical anisotropy layer forming composition (1-3) described in Example 1 was applied using a Gieser coating machine, and heated with 80°C hot air for 60 seconds. Subsequently, the obtained composition layer was irradiated with UV light (500 mJ / cm²) at 80°C. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (C1-3) corresponding to the third optical anisotropy layer was formed. The optically anisotropic layer (C1-3) had a thickness of 1.25 μm, a Δnd of 170 nm at a wavelength of 550 nm, and a torsion angle of 85° for the liquid crystal compound. When the film width direction is 0° (longitudinal direction is 90°), when viewed from the optically anisotropic layer (C1-3) side, the in-plane slow axis direction (orientation axis angle of the liquid crystal compound) was 10° on the air side and 95° on the side in contact with the alignment film (10). The in-plane slow-moving axis direction of the optical anisotropic layer is expressed by observing the substrate from the surface side of the optical anisotropic layer, with the substrate width direction being the reference 0°, and clockwise (rightward) rotation being negative and counterclockwise (leftward) rotation being positive.

[0187] Following the procedure described above, a roll-shaped laminated film (C1C) was prepared by laminating an alignment film (10) and an optically anisotropic layer (C1-3) onto a long cellulose acylate film.

[0188] (Fabrication of laminated film (C1D)) On the cellulose acylate film described in Example 1, an optical anisotropic layer-forming composition (C1-4) containing a rod-shaped liquid crystal compound of the following composition was applied using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 60°C for 1 minute, and UV irradiation (500 mJ / cm²) was performed while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (C1-4) corresponding to the fourth optical anisotropy layer was formed. The thickness of the formed optically anisotropic layer (C1-4) was 0.7 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the retardation Rth in the thickness direction at a wavelength of 550 nm was -85 nm. The average tilt angle of the rod-shaped liquid crystal compound in the direction of the long axis with respect to the film surface was 90°, confirming that it was oriented perpendicular to the film surface.

[0189] -------------------------------------------------- Composition for forming optically anisotropic layers (C1-4) -------------------------------------------------- 100 parts by mass of the above rod-shaped liquid crystal compound (A) Polymerizable monomer (A-400, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) 4.2 parts by mass 5.1 parts by mass of the polymerization initiator S-1 (oxime type) mentioned above. 3.0 parts by mass of the above photoacid generator D-1 2.0 parts by mass of the above polymer M-1 The above-mentioned vertical alignment agent S01: 2.0 parts by mass 0.4 parts by mass of the above-mentioned fluorine-containing compound A Diisopropylethylamine 2.0 parts by mass Methyl ethyl ketone 42.3 parts by mass Methyl isobutyl ketone 627.5 parts by mass --------------------------------------------------

[0190] Following the above procedure, an optically anisotropic layer (C1-4) was laminated onto a long cellulose acylate film, and a rolled laminated film (C1D) was obtained.

[0191] (Preparation of laminated film (C1)) The liquid crystal coated side of the laminated film (C1A) made of the long cellulose acylate film prepared above and the liquid crystal coated side of the laminated film (C1B) formed on the long cellulose acylate film prepared above were bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation) in a continuous machine, so that the longitudinal directions of the films were parallel. Subsequently, the cellulose acylate film on the laminated film (C1B) side was peeled off, exposing the surface of the optical anisotropy layer (C1-2) that was in contact with the cellulose acylate film. In this way, a long cellulose acylate film (C1AB) was obtained in which the optical anisotropy layer (C1-1), the adhesive layer, and the optical anisotropy layer (C1-2) were laminated in this order on the cellulose acylate film. Assuming the film's width direction is 0° (the longitudinal direction is 90° counterclockwise and -90° clockwise), the in-plane slow phase axis direction of the optically anisotropic layer (C1-2) was -14° when viewed from the optically anisotropic layer (C1-2) side. Next, the liquid crystal coated side of the optical anisotropic layer (C1-2) of the laminated film (C1AB) and the liquid crystal coated side of the laminated film (C1C) prepared above were bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation) in a continuous machine, so that the longitudinal directions of the films were parallel. Subsequently, the cellulose acylate film on the laminated film (C1C) side was peeled off, exposing the surface of the optical anisotropic layer (C1-3) that had been in contact with the cellulose acylate film. In this way, a long laminated film (C1ABC) was obtained in which the adhesive layer, optical anisotropic layer (C1-2), adhesive layer, and optical anisotropic layer (C1-3) were laminated in this order on the cellulose acylate film. Next, the liquid crystal coated side of the optical anisotropic layer (C1-3) of the laminated film (C1ABC) and the liquid crystal coated side of the laminated film (C1D) prepared above were bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation) in a continuous machine, so that the longitudinal directions of the films were parallel. Subsequently, the cellulose acylate film on the laminated film (C1ABC) side was peeled off to expose the optical anisotropic layer (C1-1). In this way, a long laminated film (C1) was obtained in which the optical anisotropic layer (C1-1), adhesive layer, optical anisotropic layer (C1-2), adhesive layer, optical anisotropic layer (C1-3), adhesive layer, and optical anisotropic layer (C1-4) were laminated in this order. The refractive index difference between the adhesive layer and each optical anisotropic layer was greater than 0.05.

[0192] (Fabrication of circular polarizing plate (PC1)) The surface of the optically anisotropic layer (C1-1) of the long laminated film (C1) prepared above and the surface of the polarizer of the long linear polarizing plate described in Example 1 (the side opposite the polarizer protective film) were continuously bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation). Subsequently, the cellulose acylate film on the optically anisotropic layer (C1-4) side was peeled off to expose the optically anisotropic layer (C1-4). In this manner, a circular polarizer (PC1) consisting of a laminated film (C1) and a linear polarizer was fabricated. At this time, the polarizer protective film, polarizer, optical anisotropy layer (C1-1), optical anisotropy layer (C1-2), optical anisotropy layer (C1-3), and optical anisotropy layer (C1-4) were laminated in this order, and the angle between the absorption axis of the polarizer and the in-plane slow axis of the optical anisotropy layer (C1-2) was 76°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of the optical anisotropy layer (C1-3) on the optical anisotropy layer (C1-2) side was 10°, and the angle with the in-plane slow axis direction of the optical anisotropy layer (C1-2) was 4°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of the optical anisotropy layer (C1-3) on the optical anisotropy layer (C1-4) side was 95°.

[0193] <Comparative Example 2> (Fabrication of laminated film (C2)) Corona treatment was performed on the surface of the optically anisotropic layer (7-2) of the laminated film (7B) prepared by the method described in Example 7. Subsequently, the optically anisotropic layer-forming composition (C1-1) described in Comparative Example 1 was applied using a Gieser coating machine to form a composition layer. The film with the composition layer formed was heated with hot air at 116°C for 1 minute, and then UV irradiation (500 mJ / cm²) was performed at a UV temperature of 78°C while purging with nitrogen to maintain an atmosphere with an oxygen concentration of 100 ppm by volume or less. 2 The orientation of the liquid crystal compound was fixed by performing the following procedure, and an optical anisotropy layer (C2-1) corresponding to the first optical anisotropy layer was formed. The thickness of the formed optically anisotropic layer (C2-1) was 0.9 μm. The in-plane retardation Re at a wavelength of 550 nm was 0 nm, and the thickness-direction retardation Rth at a wavelength of 550 nm was 40 nm. The average inclination angle of the disc surface of the disc-shaped liquid crystal compound with respect to the film surface was 0°, confirming that it was oriented horizontally with respect to the film surface. Following the above procedure, a long laminated film (C2) was obtained in which optically anisotropic layers (C2-1), (7-2), (1-3), and (1-4) were laminated in this order. No adhesive or bonding layer was placed between the optically anisotropic layers.

[0194] (Fabrication of circular polarizing plates (PC2)) The surface of the optically anisotropic layer (C2-1) of the long laminated film (C2) prepared above and the surface of the polarizer of the long linear polarizing plate described in Example 1 (the side opposite the polarizer protective film) were continuously bonded together using a pressure-sensitive adhesive Opteria NCF-D692 (5 μm, manufactured by Lintec Corporation). Subsequently, the cellulose acylate film on the optically anisotropic layer (1-4) side was peeled off to expose the optically anisotropic layer (1-4). In this manner, a circular polarizer (PC2) consisting of a laminated film (C2) and a linear polarizer was fabricated. At this time, the polarizer protective film, polarizer, optical anisotropy layer (C2-1), optical anisotropy layer (7-2), optical anisotropy layer (1-3), and optical anisotropy layer (1-4) were laminated in this order, and the angle between the absorption axis of the polarizer and the in-plane slow axis of optical anisotropy layer (7-2) was 76°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of optical anisotropy layer (1-3) on the optical anisotropy layer (7-2) side was 10°, and the angle between this and the in-plane slow axis direction of optical anisotropy layer (1-2) was 4°. Furthermore, with the width direction as the reference 0°, the in-plane slow axis direction on the surface of optical anisotropy layer (1-3) on the optical anisotropy layer (1-4) side was 95°.

[0195] <Comparative Example 3> Referring to Example 1 of Japanese Patent Publication No. 2018-087876, a cholesteric liquid crystal laminate in which cholesteric liquid crystal layers Rm1, Gm1, and Bm1 were directly laminated, and a λ / 4 phase difference plate were prepared. The in-plane retardation Re and the thickness-direction retardation Rth of the λ / 4 phase difference plate at a wavelength of 550 nm were 130 nm and -5 nm, respectively. A circular polarizer (PC3) was obtained by bonding the cholesteric liquid crystal laminate and the λ / 4 phase difference plate with SK dyne. When the transmission spectrum of the light-reflecting layer was measured using a UV-3150 spectrophotometer (Shimadzu Corporation), a decrease in transmittance due to selective reflection of the cholesteric layer was observed at wavelengths of 650 nm, 550 nm, and 750 nm, and the minimum transmittance in the wavelength range of 400 to 700 nm was less than 60%.

[0196] <Measurement of optical properties> Using an AxoScan OPMF-1 (manufactured by OptoScience Co., Ltd.), the dependence of Re on the incident light angle and the tilt angle of the optical axis (i.e., the inclination of the optical anisotropy layer surface in the direction in which the refractive index of the optical anisotropy layer is maximized) were measured at a wavelength of 550 nm, and the in-plane retardation Re and the thickness-direction retardation Rth of the optical anisotropy layer at a wavelength of 550 nm were determined, respectively.

[0197] <Film thickness measurement> The thickness of the optically anisotropic layer was measured using a reflectance spectrometer FE3000 (manufactured by Otsuka Electronics Co., Ltd.).

[0198] <Measuring refractive index> Samples were prepared by transferring each optically anisotropic layer used in each example and comparative example onto glass using an adhesive. The reflectance spectrum of the optically anisotropic layer was measured using a reflectance spectrometer FE3000 (manufactured by Otsuka Electronics Co., Ltd.), and the refractive index was calculated from the obtained reflectance spectrum. In calculating the refractive index, assuming that the refractive indices at both interfaces of the optically anisotropic layer are equal, the refractive index n at a wavelength of 550 nm was determined by fitting the reflectance spectrum to the following Cauchy dispersion formula using the least squares method. Here, C1, C2, and C3 are parameters of the n-Cauchy model, λ is the wavelength, and k is the attenuation coefficient. In addition, the thickness of the sample from which the reflectance spectrum was measured was measured using a scanning electron microscope (manufactured by Hitachi High-Technologies, S-4800), and this value was used as the thickness during fitting. As mentioned above, the refractive index calculated by the above method corresponds to the refractive index ((nx+ny) / 2) expressed by the above formula (N1).

[0199]

number

[0200] The refractive index of the adhesive layer and the tack layer was also measured using the same method as described above.

[0201] <Fabrication of Organic EL Display Devices> (Implementation on display devices) A Samsung GALAXY S4 equipped with an organic EL panel was disassembled, the circular polarizer was peeled off, and the circular polarizers prepared in Examples 1-10 and Comparative Examples 1-3 were attached to the display device using pressure-sensitive adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.) so that the polarizer protective film was positioned on the outside.

[0202] <Evaluation of display performance> The fabricated organic EL display device was shown in black, observed from the front under bright light, and evaluated according to the following criteria. The results are shown in Table 1 below. A: The reflected light is barely visible. B: Reflected light is slightly visible. C: Reflected light is visible, but it is acceptable. D: The reflected light is too strong and unacceptable.

[0203] <Evaluation of point defects> A λ / 4 plate made of polymerizable liquid crystal film was fabricated using the method described in paragraphs

[0078] to

[0086] of Japanese Patent Publication No. 2021-124641. The in-plane retardation Re(550nm) of the λ / 4 plate at a wavelength of 550nm was 142.5nm, and the Re(550nm) / Re(550nm) was 0.82. The fabricated λ / 4 plate was bonded to a linear polarizer prepared by the method of Example 1 of the present invention, and the substrate of the λ / 4 plate was peeled off to obtain a circular polarizer for inspection (T1). When the circular polarizer for inspection (T1) was observed from the λ / 4 plate side, the slow axis of the λ / 4 plate was rotated -45° clockwise with respect to the absorption axis of the polarizer. When the circular polarizer for inspection (T1) and the circular polarizers prepared in Examples 1-10 and Comparative Examples 1-3 were placed facing each other with the optical anisotropy layers facing inward, and stacked so that the absorption axes of the polarizers were at a 90° angle, it was confirmed that light leakage was largely suppressed. In this state, white light was shone from the back surface, and the frequency of defects larger than 50 μm was evaluated. A: 2 pieces / m 2 The following. (Acceptable) B:2 pieces / m 2 More, 10 pieces / m 2 The following. (Acceptable) C: 10 pieces / m 2 More than that, unacceptable.

[0204] <Refractive index difference> The difference in refractive index between the adhesive layer or bonding layer and the optical anisotropy layer affects the display performance, and was evaluated according to the following criteria. In Example 3, the difference in refractive index between the adhesive layer and one of the optical anisotropy layers adjacent to it was evaluated as C, and is therefore shown as "C" in Table 1 below. A: The refractive index difference between the adhesive layer or bonding layer and the adjacent optically anisotropic layer is 0.05 or less. B: The refractive index difference between the adhesive layer or bonding layer and the optically anisotropic layer is greater than 0.05 and less than or equal to 0.10. C: The refractive index difference between the adhesive layer or bonding layer and the optically anisotropic layer is greater than 0.10.

[0205] <Visible light transmittance> The laminated films (1) to (10) and (C1) to (C3) prepared in Examples 1 to 10 and Comparative Examples 1 to 3 were bonded to a glass plate using pressure-sensitive adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.) on the surface opposite to the cellulose acylate film, and the laminated films were transferred onto the glass by peeling off the cellulose acylate film. Using a spectrophotometer (UV-3150, manufactured by Shimadzu Corporation), the transmittance of laminated films transferred onto glass (Eagle Glass, manufactured by Corning) at 10 nm intervals within a predetermined wavelength range (wavelength 400-700 nm or 450-700 nm) was measured, with glass serving as the baseline. The lowest transmittance within the predetermined wavelength range was evaluated according to the following criteria. A: The transmittance at the wavelength with the lowest transmittance within the given wavelength range exceeds 90%. B: The transmittance at the wavelength with the lowest transmittance within the specified wavelength range is 90% or less, or 60% or more. C: The transmittance at the wavelength with the lowest transmittance within the given wavelength range is less than 60%.

[0206] The "Number of Adhesive Layers" column in the table indicates how many of the following spaces—between the first and second optical anisotropy layers, between the second and third optical anisotropy layers, and between the third and fourth optical anisotropy layers—are equipped with an adhesive layer. In the table, the "Refractive Index of Adhesive Layer" column indicates the refractive index of the adhesive layer or glue layer used.

[0207] [Table 1]

[0208] As shown in the table above, the laminated film of the present invention exhibited the desired effects. A comparison of Examples 1-3 confirmed that meeting any one of requirements Y1-Y3 resulted in superior performance. A comparison of Examples 1-3 and Examples 4-7 confirmed that the occurrence of point defects is further suppressed when an alignment film is not placed between the two optically anisotropic layers. [Explanation of Symbols]

[0209] 10A, 10B, 10C Laminated Film 12. First optical anisotropy layer 14. Second optical anisotropy layer 16. Third optical anisotropy layer 18. Fourth optical anisotropy layer 20 Close contact layer

Claims

1. A laminated film having a first optical anisotropy layer, a second optical anisotropy layer, a third optical anisotropy layer, and a fourth optical anisotropy layer in this order, The first optical anisotropic layer, the second optical anisotropic layer, the third optical anisotropic layer, and the fourth optical anisotropic layer are all layers on which oriented liquid crystal compounds are fixed. An adhesion layer, selected from the group consisting of an adhesive layer and a tack layer, is provided between the first optical anisotropy layer and the second optical anisotropy layer, between the second optical anisotropy layer and the third optical anisotropy layer, and between the third optical anisotropy layer and the fourth optical anisotropy layer, in only one of these locations. The minimum transmittance of the laminated film in the wavelength range of 400 to 700 nm is 60% or more. At least one of the first to fourth optically anisotropic layers is an A plate. At least one of the first to fourth optically anisotropic layers is a layer in which a torsion-oriented liquid crystal compound is fixed. Only one of the first to fourth optically anisotropic layers is a positive C plate. A laminated film having an in-plane retardation of 100–180 nm at a wavelength of 550 nm.

2. A laminated film according to claim 1, satisfying one or two of requirements X1 to X3. Requirement X1: The first optical anisotropic layer and the second optical anisotropic layer are in direct contact or laminated with an alignment film in between, and the orientation direction of the liquid crystal compound on the surface of the first optical anisotropic layer facing the second optical anisotropic layer is different from the orientation direction of the liquid crystal compound on the surface of the second optical anisotropic layer facing the first optical anisotropic layer. Requirement X2: The second optical anisotropic layer and the third optical anisotropic layer are in direct contact or laminated with an alignment film in between, and the orientation direction of the liquid crystal compound on the surface of the second optical anisotropic layer facing the third optical anisotropic layer is different from the orientation direction of the liquid crystal compound on the surface of the third optical anisotropic layer facing the second optical anisotropic layer. Requirement X3: The third optical anisotropic layer and the fourth optical anisotropic layer are in direct contact or laminated with an alignment film in between, and the orientation direction of the liquid crystal compound on the surface of the third optical anisotropic layer facing the fourth optical anisotropic layer is different from the orientation direction of the liquid crystal compound on the surface of the fourth optical anisotropic layer facing the third optical anisotropic layer.

3. A laminated film according to claim 1 or 2, satisfying any one of requirements Y1 to Y3. Requirement Y1: The adhesion layer is disposed between the first optical anisotropy layer and the second optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the first optical anisotropy layer is 0.10 or less, and the difference between the refractive index of the adhesion layer and the refractive index of the second optical anisotropy layer is 0.10 or less. Requirement Y2: The adhesion layer is disposed between the second optical anisotropy layer and the third optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the second optical anisotropy layer is 0.10 or less, and the difference between the refractive index of the adhesion layer and the refractive index of the third optical anisotropy layer is 0.10 or less. Requirement Y3: The adhesion layer is disposed between the third optical anisotropy layer and the fourth optical anisotropy layer, the difference between the refractive index of the adhesion layer and the refractive index of the third optical anisotropy layer is 0.10 or less, and the difference between the refractive index of the adhesion layer and the refractive index of the fourth optical anisotropy layer is 0.10 or less.

4. The laminated film according to any one of claims 1 to 3, wherein the first optical anisotropy layer and the second optical anisotropy layer are in direct contact, the adhesion layer is disposed between the second optical anisotropy layer and the third optical anisotropy layer, and the third optical anisotropy layer and the fourth optical anisotropy layer are in direct contact.

5. The laminated film according to any one of claims 1 to 4, wherein the adhesion layer is a layer formed using an ultraviolet-curing adhesive.

6. A laminated film according to any one of claims 1 to 5, wherein the thickness is 20 μm or less.

7. A circular polarizing plate comprising a laminated film according to any one of claims 1 to 6 and a polarizer.

8. The circular polarizer according to claim 7, wherein there is no polymer film between the laminated film and the polarizer.

9. A display device comprising a laminated film according to any one of claims 1 to 6, or a circular polarizing plate according to claim 7 or 8.

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