Laminate, display device, and wound body

Abstract

The present invention addresses the problem of providing a laminate from which a larger number of members that suppress the occurrence of ghosts can be cut out in application to a head mounted display. The laminate of the present invention includes a first optically anisotropic film and a second optically anisotropic film. Where the average orientation in the direction in which the optical anisotropy of the first optically anisotropic film at each position of a specific position group in a region X is the largest is defined as a first average orientation, and the average orientation in the direction in which the optical anisotropy of the second optically anisotropic film at each position of the specific position group in the region X is the largest is defined as a second average orientation, the maximum value of the angle between the direction in which the optical anisotropy of the first optically anisotropic film is the largest and the first average orientation is within the range of 0.5-5.0° and the angle α formed by the first average orientation and the second average orientation satisfies the relationship in formula (1). Where the angle formed by the direction in which the optical anisotropy of the first optically anisotropic film is the largest and the direction in which the optical anisotropy of the second optically anisotropic film is the largest is defined as an angle β, the angle β satisfies the relationship of formula (2).　Formula (1): 10°<α<80° Formula (2): 0°≤|β-α|<1°

Description

Laminate, display device and roll

[0001] The present invention relates to a laminate. More specifically, the present invention relates to a laminate including two optically anisotropic films. The present invention also relates to a display device having the laminate. The present invention also relates to a rolled body.

[0002] In recent years, virtual reality display devices have been put to practical use. For example, a head-mounted display having a display panel and a lens can be cited as an example of a virtual reality display device. When such a head-mounted display is worn on the head of an observer and an image is displayed through the lens, the observer can view a realistic image. In such a head-mounted display, a lens using a reflective optical system is sometimes adopted to reduce the thickness. In the reflective optical system, a reflective polarizer is used, as in the head-mounted display shown in Patent Document 1, for example.

[0003] Special Publication No. 2020-519964

[0004] In head-mounted displays (hereinafter also referred to as HMDs) described in Patent Document 1 and the like, when various components such as reflective polarizers are applied, typically, portions are cut out of the various components to fit the size of use, and the cut-out components are often used. The inventors have studied HMDs using components such as the above-described cut-out reflective polarizers and have found that ghosts (undesirable images) may occur depending on the cut-out position of the components, and that this issue needs to be addressed. In other words, they have found that the characteristics exhibited by the cut-out components differ depending on the cut-out position from various components (laminates). Therefore, an object of the present invention is to provide a laminate from which a larger number of components that suppress the generation of ghosts when applied to a head-mounted display can be cut out. Another object of the present invention is to provide a display device. Another object of the present invention is to provide a wound body.

[0005] The present inventors have conducted extensive research to solve the above problems and have completed the present invention. That is, they have found that the above problems can be solved by the following configuration.

[0006] [1] A laminate comprising a first optically anisotropic film and a second optically anisotropic film, wherein a first average orientation is defined as an average orientation in a direction in which the optical anisotropy of the first optically anisotropic film is maximized at each position of a specific position group consisting of positions corresponding to each vertex of the square, midpoint positions of each side of the square, and a center of gravity position of the square within a 50 cm x 50 cm square area X within the plane of the laminate, and a second average orientation is defined as an average orientation in a direction in which the optical anisotropy of the second optically anisotropic film is maximized at each position of the specific position group within the area X, the maximum value of the angle between the direction in which the optical anisotropy of the first optically anisotropic film is maximized at each position of the specific position group and the first average orientation is within the range of 0.5 to 5.0°, and the angle α between the first average orientation and the second average orientation satisfies the relationship of formula (1), A laminate, wherein, when the angle β is defined as the angle formed between the direction in which the optical anisotropy of the first optically anisotropic film is maximized and the direction in which the optical anisotropy of the second optically anisotropic film is maximized at any position within the region X, the angle β at each position of the specific position group satisfies the relationship of formula (2). Formula (1): 10°<α<80° Formula (2): 0°≦|β-α|<1° [2] The laminate according to [1], which is in a long shape. [3] The laminate according to [2], which has the first average orientation at an angle of 80 to 100° with respect to the long direction of the long shape. [4] The laminate according to any one of [1] to [3], wherein the first optically anisotropic film is a stretched film. [5] The laminate according to any one of [1] to [4], wherein the first optically anisotropic film is a reflective linear polarizer. [6] The laminate according to any one of [1] to [5], wherein the second optically anisotropic film has an in-plane retardation of 110 to 170 nm at a wavelength of 550 nm. [7] The laminate according to any one of [1] to [6], wherein the angle α is 43 to 47°. [8] The laminate according to any one of [1] to [7], wherein the second optically anisotropic film contains an oriented liquid crystal compound. [9] The laminate according to any one of [1] to [8], wherein the second optically anisotropic film contains a liquid crystal compound in a twisted nematic orientation.

[10] The laminate according to any one of [1] to [9], wherein the first optically anisotropic film is adjacent to the second optically anisotropic film.

[11] The laminate according to any one of [1] to

[10] , comprising a photo-alignment layer between the first optically anisotropic film and the second optically anisotropic film.

[12] A display device comprising the laminate according to any one of [1] to

[11] .

[13] The display device according to

[12] , which is a virtual reality display device.

[14] A rolled body obtained by rolling up the long laminate according to any one of [1] to

[11] .

[0007] According to the present invention, it is possible to provide a laminate from which a larger number of members that suppress the occurrence of ghosts can be cut out when applied to a head-mounted display. Further, according to the present invention, it is possible to provide a display device. Further, according to the present invention, it is possible to provide a wound body.

[0008] It is a schematic cross-sectional view of an example of the laminate of the present invention.It is a top view of the laminate.It is a bottom view of the laminate.It is a schematic view showing an example of the configuration of the virtual reality display device.

[0009] The present invention will be described in detail below. The following description of the components may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0010] The following describes the meanings of each description in this specification. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In this specification, "absorption axis" means the polarization direction in which absorbance is maximized in-plane when linearly polarized light is incident. Furthermore, "reflection axis" means the polarization direction in which reflectance is maximized in-plane when linearly polarized light is incident. Furthermore, "transmission axis" means the direction in-plane that is perpendicular to the absorption axis or reflection axis. Furthermore, "in-plane slow axis" means the direction in which refractive index is maximized in-plane.

[0011] In this specification, the terms "perpendicular" and "parallel" include the range of error permitted in the technical field to which the present invention pertains. Specifically, this means that the error from the exact angle is within ±10°, and the error from the exact angle is preferably within ±5°, and more preferably within ±3°.

[0012] In this specification, Re(λ) and Rth(λ) represent the in-plane retardation and the thickness retardation, respectively, at a wavelength λ. Unless otherwise specified, the wavelength λ is 550 nm. In the present invention, Re(λ) and Rth(λ) are values ​​measured at a wavelength λ using an AxoScan (manufactured by Axometrics). By inputting the average refractive index ((nx + ny + nz) / 3) and film thickness (d (μm)) into AxoScan, the following in-plane slow axis direction (°) is calculated: Re(λ) = R0(λ) Rth(λ) = ((nx + ny) / 2 - nz) × d. Note that R0(λ) is displayed as a numerical value calculated by AxoScan, but it means Re(λ).

[0013] In this specification, the refractive indices nx, ny, and nz are measured using an Abbe refractometer (NAR-4T, manufactured by Atago Co., Ltd.) with a sodium lamp (λ = 589 nm) as a light source. When measuring wavelength dependency, measurements can be made using a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.) in combination with an interference filter. Values ​​from the Polymer Handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can also be used. Examples of average refractive index values ​​for major optical films are listed below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).

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

[0015] <Laminate> The laminate of the present invention includes a first optically anisotropic film and a second optically anisotropic film. In the laminate of the present invention, the maximum value of the angle formed by the direction in which the optical anisotropy of the first optically anisotropic film is maximized at each of a group of specific positions within a 50 cm × 50 cm square region X in a plane, the positions corresponding to the vertices of the square, the midpoints of each side of the square, and the center of gravity of the square, is within the range of 0.5 to 5.0°. In the laminate of the present invention, when the angle between the first average orientation and a second average orientation, which is the average orientation of the direction in which the optical anisotropy of the second optically anisotropic film is maximized at each position of the specific position group within region X, is defined as angle α, and the angle between the direction in which the optical anisotropy of the first optically anisotropic film is maximized at any position within region X and the direction in which the optical anisotropy of the second optically anisotropic film is maximized at any position within region X is defined as angle β, angle α and angle β at each position of the specific position group satisfy the relationships of the following formulas (1) and (2): Formula (1) 10°<α<80° Formula (2) 0°≦|β-α|<1° Hereinafter, the direction in which the optical anisotropy of the first optically anisotropic film is maximized at any position within region X will be referred to as the "first anisotropy orientation," and the direction in which the optical anisotropy of the second optically anisotropic film is maximized at any position within region X will also be referred to as the "second anisotropy orientation."

[0016] Although the mechanism by which the laminate of the present invention can cut out a larger number of components that suppress the generation of ghosts when applied to a head-mounted display is not entirely clear, the inventors speculate as follows. In the laminate of the present invention, the maximum value of the angle between the first average orientation in the first optically anisotropic film and the first anisotropic orientation at each position of the specific position group is in the range of 0.5 to 5.0°. That is, in the first optically anisotropic film, the first average orientation and the first anisotropic orientation at any position of the specific position group are not strictly parallel (see FIG. 2). Furthermore, in the laminate of the present invention, the angle α between the second average orientation and the first average orientation satisfies the relationship of formula (1), so the laminate of the present invention can exhibit desired optical properties. Here, in the laminate of the present invention, the angle β between the first anisotropic orientation and the second anisotropic orientation at each position of the specific position group and the angle α satisfies the relationship of formula (2). When the relationship of formula (1) is satisfied and the relationship of formula (2) is satisfied, the optical characteristics resulting from the relationship of formula (1) are similarly satisfied at each position of the specific position group, even though the first average orientation and the first anisotropic orientation at any position of the specific position group are not strictly parallel (see Figure 3). In this case, when the laminate of the present invention is applied to an HMD, similar optical characteristics are generated at any position of the specific position group of the laminate, so it is thought that it is possible to cut out many components that suppress the generation of ghosts.

[0017] The orientation relationship of the laminate of the present invention will be described below with reference to the drawings. Fig. 1 shows a cross-sectional schematic diagram of an example of the laminate of the present invention. As shown in Fig. 1, the laminate 10 includes a first optically anisotropic film 12 and a second optically anisotropic film 14. As will be described later, the laminate 10 may include components other than the first optically anisotropic film 12 and the second optically anisotropic film 14.

[0018] 2 is a top view of the laminate 10 observed from the direction of the white arrow in FIG. 1 . That is, FIG. 2 is a view of the laminate 10 observed from the first optically anisotropic film 12 side, and in FIG. 2, the first optically anisotropic film 12 of the laminate 10 is observed. The curved solid line in the first optically anisotropic film 12 in FIG. 2 virtually shows the distribution in the xy plane of the first anisotropy orientation (the direction in which the optical anisotropy is greatest) at each point in the plane of the first optically anisotropic film 12. As shown in FIG. 2 , the first anisotropy orientation of the first optically anisotropic film 12 included in the laminate 10 of the present invention is not uniform in-plane. In the embodiment shown in FIG. 2 , the first anisotropy orientation of the first optically anisotropic film 12 is, on average, oriented in the y-axis direction in FIG. 2 , but at one end side and the other end side in the y-axis direction, the first average orientation is tilted with respect to the y-axis direction. Such a tilt of the first average orientation is caused, for example, by the so-called bowing phenomenon, which can occur when the first optically anisotropic film 12 is formed by stretching, and will be described in detail later.

[0019] Furthermore, the region X defined by the dotted line in FIG. 2 is a 50 cm × 50 cm square region in the xy plane direction. In the laminate 10 of the present invention, the maximum value of the angle between the first average orientation AD1, which is the average orientation in the direction in which the optical anisotropy of the first optically anisotropic film 12 is greatest at each position of the specific position group within region X, and the first anisotropy orientation at each position of the specific position group, is within the range of 0.5 to 5.0°. This relationship will be explained below. Positions A to I in FIG. 2 are positions within region X and correspond to each position of the specific position group. Positions A, C, G, and I correspond to each vertex of region X. Positions B, D, F, and H are the midpoints of each side of region X. Position E is the center of gravity of region X (which also corresponds to the intersection of the diagonals of the vertices). 2 representatively shows only the first anisotropy orientation D1a at position A, but positions B to I also have first anisotropy orientations D1b to D1i, respectively, similar to position A. In Fig. 2, the first average orientation AD1, which is the average orientation in which the optical anisotropy of the first optically anisotropic film 12 is greatest at each position of the specific position group within region X, is the average orientation of the first anisotropy orientations D1a to D1i, and is parallel to the y-axis direction as shown in Fig. 2. In this case, in the laminate 10 of the present invention, the maximum value of the angle between the first average orientation AD1 and the first anisotropy orientations D1a to D1i is within the range of 0.5 to 5.0°.

[0020] Figure 3 is a bottom view of the laminate 10 observed from the side opposite to the direction of the white arrow in Figure 1. That is, Figure 3 is a view of the laminate 10 observed from the side of the second optically anisotropic film 14, and in Figure 3, the second optically anisotropic film 14 of the laminate 10 is observed. Figure 3 also shows region X, which corresponds to Figure 2 above, and positions A to I. The relationship between the above-mentioned formulas (1) and (2) will be explained below.

[0021] The second optically anisotropic film 14 has a second anisotropy orientation (not shown) at each point in the plane. In FIG. 3, only the second anisotropy orientation D2a at position A is representatively shown, but positions B to I also have second anisotropy orientations D2b to D2i, respectively, similar to position A. In FIG. 3, the second average orientation AD2, which is the average orientation in the direction in which the optical anisotropy of the second optically anisotropic film 14 is greatest at each position of the specific position group within region X, is the average orientation of the second anisotropy orientations D2a to D2i. In addition, in FIG. 3, the first average orientation AD1 shown in FIG. 2 and the first anisotropy orientation D1a at position A are shown by dotted lines. Here, if the angle between the first average orientation AD1 and the second average orientation AD2 is angle α, the laminate 10 of the present invention satisfies the relationship of the following formula (1): Formula (1) 10°<α<80°

[0022] Furthermore, if the angle between the second anisotropic orientation D2a and the first anisotropic orientation D1a is defined as angle β, the laminate 10 of the present invention satisfies the relationship of the following formula (2): 0°≦|β-α|<1° Formula (2) Here, in the laminate 10 of the present invention, the angle β calculated at each position of the specific position group satisfies the relationship of formula (2) above, meaning that the angles β calculated at the positions A to I respectively satisfy the relationship of formula (2).

[0023] The laminate 10 of the present invention has a maximum value of the angle between the first average orientation AD1 and the first anisotropic orientations D1a to D1i that is within the range of 0.5 to 5.0°, and by satisfying the relationships of the above formulas (1) and (2), it is believed that the occurrence of ghosts is suppressed when applied to a head-mounted display due to the mechanism described above.

[0024] The directions of the first anisotropy orientations (first anisotropy orientations D1a to D1i) of the first optically anisotropic film 12 at the positions A to I can be measured using an AxoScan (polarimeter) device from Axometrics and analysis software from the same company. The directions of the first anisotropy orientations (second anisotropy orientations D2a to D2i) of the second optically anisotropic film 14 at the positions A to I can be measured in the same manner as the first anisotropy orientation.

[0025] The shape of the laminate 10 is not particularly limited, but is preferably a long shape. When the laminate 10 is long, the laminate 10 may be wound into a wound body. When the laminate 10 is long, the first average orientation (first average orientation AD1 in FIG. 2) is preferably 80 to 100°, more preferably 85 to 95°, with respect to the long direction (lengthwise direction) of the long shape.

[0026] The angle α between the first average orientation AD1 and the second average orientation AD2 is preferably 15 to 75°, more preferably 25 to 60°, even more preferably 40 to 50°, and particularly preferably 43 to 47°. The in-plane retardation Re(550) of the second optically anisotropic film 14 at a wavelength of 550 nm is preferably 110 to 170 nm, more preferably 120 to 160 nm, even more preferably 125 to 160 nm, and particularly preferably 130 to 150 nm.

[0027] The laminate 10 has a size of more than 50 cm x 50 cm.

[0028] 1, the first optically anisotropic film 12 and the second optically anisotropic film 14 are adjacent to each other, but the laminate of the present invention may include another layer between the first optically anisotropic film and the second optically anisotropic film. Examples of the other layer include an alignment layer (more preferably a photoalignment layer) described below.

[0029] Hereinafter, the first optically anisotropic film, the second optically anisotropic film, and the laminate of the present invention may have various configurations.

[0030] [First Optically Anisotropic Film] The laminate of the present invention has a first optically anisotropic film. As described above, the first optically anisotropic film has a maximum angle between the first average orientation in region X and the first anisotropic orientation at each position of the specific position group in the range of 0.5 to 5.0°. The first optically anisotropic film is not particularly limited as long as it satisfies the above requirements, but is preferably a polarizer. The polarizer is preferably a linear polarizer. Examples of linear polarizers include reflective linear polarizers and absorptive linear polarizers, with reflective linear polarizers being preferred.

[0031] Hereinafter, a reflective linear polarizer and an absorptive linear polarizer will be described as the first optically anisotropic film.

[0032] (Reflective Linear Polarizer) A reflective linear polarizer is a linear polarizer that transmits linearly polarized light in a certain direction (transmission axis direction) and reflects linearly polarized light in a direction perpendicular to the linearly polarized light (reflection axis direction). In a reflective linear polarizer, the direction in which the optical anisotropy is greatest (first anisotropy orientation) is the reflection axis direction. Any known reflective linear polarizer can be used as the reflective polarizer as long as it selectively transmits linearly polarized light in a certain direction in the wavelength range of visible light. An example of a reflective linear polarizer is a film obtained by stretching a dielectric multilayer film as described in JP 2011-053705 A. In addition, commercially available reflective linear polarizers can also be suitably used. An example of a commercially available reflective linear polarizer is a reflective linear polarizer (product name APF) manufactured by 3M.

[0033] In a reflective linear polarizer that is a stretched film as described above, the reflection axis may become nonuniform in the in-plane direction of the film during stretching. More specifically, a reflective linear polarizer that is a stretched film is often formed by stretching in a direction perpendicular to the conveying direction, which is prone to the so-called bowing phenomenon. When the bowing phenomenon occurs, the molecular orientation state differs between the central portion and the edge portions in the width direction of the stretched film, and as a result, the direction of the reflection axis is likely to vary depending on the in-plane position. When such a reflective linear polarizer is used as the first optically anisotropic film, the maximum value of the angle between the first average orientation in region X and the first anisotropic orientation at each position in the specific position group is likely to be within the range of 0.5 to 5.0 degrees.

[0034] (Absorptive Linear Polarizer) An absorptive linear polarizer is a linear polarizer that transmits linearly polarized light in a certain direction (transmission axis direction) and absorbs linearly polarized light in a direction perpendicular to this linearly polarized light (absorption axis direction). In an absorptive linear polarizer, the direction in which the optical anisotropy is greatest (first anisotropy orientation) is the absorption axis direction. A general polarizer can be used as the absorptive linear polarizer. For example, a polarizer obtained by dyeing a dichroic material into polyvinyl alcohol or other polymer resin and then stretching the polymer resin to orient the material may be used, or a polarizer obtained by aligning a dichroic material by utilizing the orientation of a liquid crystal compound may be used. In particular, when an absorptive linear polarizer formed by stretching is used as the first optically anisotropic film, the maximum angle between the first average orientation in region X and the first anisotropic orientation at each position in the specific position group tends to be within the range of 0.5 to 5.0°.

[0035] The absorptive linear polarizer may contain a liquid crystal compound and a dichroic material. The absorptive linear polarizer containing a liquid crystal compound and a dichroic material may be a coated polarizer. The coated polarizer refers to a polarizer that can be formed by coating a composition containing a liquid crystal compound and a dichroic material. The absorptive linear polarizer may be an absorptive linear polarizer obtained by coating a composition containing a liquid crystal compound having a polymerizable group and a dichroic material, orienting the liquid crystal compound, and polymerizing the polymerizable group to fix the orientation state of the liquid crystal compound.

[0036] [Second Optically Anisotropic Film] The laminate of the present invention has a second optically anisotropic film. The second optically anisotropic film satisfies the above-mentioned formula (1) and formula (2) in relation to the first optically anisotropic film. The second optically anisotropic film is not particularly limited as long as it satisfies the above-mentioned requirements in relation to the first optically anisotropic film, but it is preferable that the second optically anisotropic film is a retardation film having in-plane retardation. When the second optically anisotropic film is a retardation film, the direction in which the optical anisotropy of the second optically anisotropic film is greatest (second anisotropy orientation) is the in-plane slow axis direction. When a retardation film is used as the second optically anisotropic film and a linear polarizer is used as the first optically anisotropic film, the above-mentioned angle α (the angle between the first average orientation and the second average orientation) satisfies the relationship of formula (1), and therefore the laminate of the present invention can function as an elliptical polarizing plate. Furthermore, when a retardation film is used as the second optically anisotropic film and a reflective linear polarizer is used as the first optically anisotropic film, the laminate of the present invention can function as a reflective elliptically polarizing plate.

[0037] When the second optically anisotropic film is a retardation film, the retardation film is preferably a λ / 4 plate. A λ / 4 plate is a plate having a λ / 4 function, specifically, a plate having the function of converting linearly polarized light of a certain wavelength (preferably visible light) into circularly polarized light (or circularly polarized light into linearly polarized light). The in-plane retardation (Re(550)) at a wavelength of 550 nm of the second optically anisotropic film is preferably 110 to 170 nm, more preferably 120 to 160 nm, even more preferably 125 to 160 nm, and particularly preferably 130 to 150 nm. In addition to λ / 4 plates, retardation films whose in-plane retardation at a wavelength of 550 nm is 3 / 4 or 5 / 4 of the wavelength of any light in visible light are also preferred. When a retardation film that is a λ / 4 plate is used as the second optically anisotropic film and a linear polarizer is used as the first optically anisotropic film, the laminate of the present invention can function as a circular polarizing plate. In this case, the angle α is preferably 15 to 75°, more preferably 25 to 60°, even more preferably 35 to 55°, particularly preferably 40 to 50°, more particularly preferably 43 to 47°, and most preferably 44 to 46°. The angle α may be 45°. Furthermore, when the second optically anisotropic film contains a liquid crystal compound in a twisted orientation (more preferably a twisted nematic orientation), the angle α is preferably 25 to 60°, more preferably 25 to 50°, and even more preferably 25 to 46°.

[0038] The retardation film may have reverse wavelength dispersion. Having reverse wavelength dispersion means that the retardation value at a wavelength increases as the wavelength increases. Specifically, the Re(450) / Re(550) of the retardation film is preferably 0.70 or more and less than 1.00, more preferably 0.80 to 0.90. Furthermore, the Re(650) / Re(550) of the retardation film is preferably more than 1.00 and 1.20 or less, more preferably 1.01 to 1.10.

[0039] The retardation film may have a multi-layer structure, and a specific example of such a structure is a broadband λ / 4 plate formed by laminating a λ / 4 plate and a λ / 2 plate. The λ / 2 plate is a plate having a λ / 2 function, specifically, a plate having a function of converting linearly polarized light of a specific wavelength (preferably visible light) into linearly polarized light in an orthogonal direction.

[0040] The second optically anisotropic film preferably contains a liquid crystal compound, and more preferably is a film in which the alignment direction of the liquid crystal compound is fixed. When the second optically anisotropic film contains a liquid crystal compound, the liquid crystal compound may already lose its liquid crystallinity in the second optically anisotropic film. The "fixed" state refers to a state in which the alignment of the liquid crystal compound is maintained. Specifically, it is preferable that the layer has no fluidity and can stably maintain the fixed alignment state without causing changes in the alignment state due to external fields or external forces, usually within a temperature range of 0 to 50°C, or under more severe conditions, within a temperature range of -30 to 70°C.

[0041] The liquid crystal compound may be a rod-shaped liquid crystal compound or a discotic liquid crystal compound. The liquid crystal compound may be either a low-molecular-weight or polymeric liquid crystal compound. Polymeric compounds generally refer to compounds with a degree of polymerization of 100 or more (see "Polymer Physics: Phase Transition Dynamics," by Masao Doi, p. 2, Iwanami Shoten, 1992). While any liquid crystal compound can be used in the second optically anisotropic film, rod-shaped or discotic liquid crystal compounds are preferred, with rod-shaped liquid crystal compounds being more preferred. Two or more rod-shaped liquid crystal compounds, two or more discotic liquid crystal compounds, or a mixture of rod-shaped and discotic liquid crystal compounds may also be used. Examples of rod-shaped liquid crystal compounds that can be preferably used include those described in claim 1 of JP-A-11-513019 and paragraphs 0026 to 0098 of JP-A-2005-289980. As the discotic liquid crystal compound, for example, those described in paragraphs 0020 to 0067 of JP-A No. 2007-108732 and paragraphs 0013 to 0108 of JP-A No. 2010-244038 can be preferably used.

[0042] The liquid crystal compound may also have a polymerizable group. The liquid crystal compound has a polymerizable group, and the alignment of the liquid crystal compound can be fixed by polymerizing the liquid crystal compounds with each other or with other compounds via the polymerizable group. A liquid crystal compound having a polymerizable group is also referred to as a polymerizable liquid crystal compound. The polymerizable group is not particularly limited, but a functional group capable of an addition polymerization reaction is preferred, a polymerizable ethylenically unsaturated group or a ring-polymerizable group is more preferred, and a (meth)acryloyl group, a vinyl group, a styryl group, or an allyl group is even more preferred. After the liquid crystal compound is fixed by polymerization or the like to form the second optically anisotropic film, the liquid crystal compound no longer needs to exhibit liquid crystallinity.

[0043] The orientation of the liquid crystal compound is not particularly limited as long as the second optically anisotropic film satisfies the above-mentioned formulas (1) and (2) in relation to the first optically anisotropic film. Regarding the orientation direction of the liquid crystal compound, when the liquid crystal compound contains a rod-shaped liquid crystal compound, the rod-shaped liquid crystal compound is preferably horizontally aligned. Horizontal alignment of the rod-shaped liquid crystal compound means that the long axis of the rod-shaped liquid crystal compound is parallel to the main surface of the second optically anisotropic film. Strict parallelism is not required, and the angle between the long axis of the rod-shaped liquid crystal compound and the main surface of the second optically anisotropic film is preferably in the range of 0±20°, more preferably 0±10°. Furthermore, when the liquid crystal compound contains a discotic liquid crystal compound, the discotic liquid crystal compound is preferably vertically aligned. Vertical alignment of the discotic liquid crystal compound means that the discotic plane of the discotic liquid crystal compound is perpendicular to the main surface of the second optically anisotropic film. However, it is not required that the angle be strictly perpendicular, and the angle between the discotic plane of the discotic liquid crystal compound and the main surface of the second optically anisotropic film is preferably in the range of 90±20°, more preferably in the range of 90±10°.

[0044] Furthermore, when the second optically anisotropic film contains a liquid crystal compound, the liquid crystal compound is preferably twisted, and more preferably twisted nematically. The twisted orientation (more preferably twisted nematic orientation) is preferably a twisted orientation with the thickness direction of the second optically anisotropic film as the helical axis. The second optically anisotropic film containing the twisted (more preferably twisted nematic) liquid crystal compound can be formed, for example, from a liquid crystal composition containing a liquid crystal compound and a chiral agent. The chiral agent refers to a compound capable of inducing twisted orientation in a liquid crystal compound. The ability of the chiral agent to induce twisted orientation (helix induction force) may or may not change upon light irradiation. The direction of the helix induction force is not particularly limited. The chiral agent may or may not exhibit liquid crystallinity.

[0045] Chiral agents (photoreactive chiral agents) whose helical twisting power changes upon irradiation with light include compounds having a chiral moiety and a photoreactive moiety whose structure changes upon irradiation with light, such as compounds that significantly change the twisting power of a liquid crystal compound depending on the amount of irradiation. Examples of photoreactive moieties whose structure changes upon irradiation with light include photochromic compounds (Kingo Uchida, Masahiro Irie, Chemical Industry, Vol. 64, p. 640, 1999; Kingo Uchida, Masahiro Irie, Fine Chemical, Vol. 28(9), p. 15, 1999). The structural change refers to decomposition, addition reaction, isomerization, racemization, [2+2] photocyclization, dimerization, and the like, which occur upon irradiation of the photoreactive moiety with light, and the structural change may be irreversible. Examples of chiral moieties include the asymmetric carbons described in Hiroyuki Nodaira, Chemistry Review, No. 22, Chemistry of Liquid Crystals, p. 73, 1994. Two or more of the above chiral agents may be used simultaneously, and a photoreactive chiral agent and a non-photoreactive chiral agent may be used in combination.

[0046] When the second optically anisotropic film contains a liquid crystal compound with a twisted orientation (more preferably a twisted nematic orientation), it is preferable that the orientation direction of the liquid crystal compound on the surface of the second optically anisotropic film facing the first optically anisotropic film is parallel to the first anisotropic orientation at each point of the first optically anisotropic film.

[0047] [Alignment Layer] The laminate of the present invention may have an alignment layer. The alignment layer can be formed by means of rubbing an organic compound (preferably a polymer), oblique deposition of an inorganic compound, formation of a layer with microgrooves, or deposition of an organic compound (e.g., ω-tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearate) by the Langmuir-Blodgett method (LB film). Furthermore, alignment layers that exhibit alignment function upon application of an electric field, application of a magnetic field, or irradiation with light (preferably polarized light) are also known. In other words, the alignment layer may be a photo-alignment layer. It is also preferable to form the alignment layer by rubbing a polymer.

[0048] The alignment layer is preferably disposed adjacent to the second optically anisotropic film. In particular, when the second optically anisotropic film contains a liquid crystal compound, the alignment direction of the liquid crystal compound can be controlled by the alignment layer. When the alignment layer is a photo-alignment layer, the alignment layer is preferably disposed between the first optically anisotropic film and the second optically anisotropic film. When forming the photo-alignment layer, a layer containing a component capable of forming a photo-alignment layer may be formed on one side of the first optically anisotropic film, and the photo-alignment layer may be formed by irradiating the other side with unpolarized light. By forming the photo-alignment layer according to the above procedure, a photo-alignment layer having an alignment control force corresponding to the distribution of the first anisotropic orientation possessed by the first optically anisotropic film can be formed.

[0049] The thickness of the alignment film is not particularly limited as long as it can exhibit an alignment function, but is preferably 0.01 to 5.0 μm, more preferably 0.05 to 2.0 μm, and even more preferably 0.1 to 0.5 μm.

[0050] [Substrate] The laminate of the present invention may further include a substrate. The substrate is preferably a transparent substrate. The transparent substrate refers to a substrate having a visible light transmittance of 60% or more, preferably 80% or more, and more preferably 90% or more. There is no particular upper limit, but 99.9% or less is preferred. 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.

[0051] The substrate may also be composed of a laminate of multiple sheets. The surface of the substrate may be subjected to a surface treatment (e.g., glow discharge treatment, corona discharge treatment, ultraviolet (UV) treatment, or flame treatment) to improve adhesion with a layer to be formed thereon. An adhesive layer (undercoat layer) may also be formed on the substrate. The substrate may also be a so-called temporary support. For example, after the first optically anisotropic film and the second optically anisotropic film are formed on the substrate, the substrate may be peeled off from the optically anisotropic layer, if necessary.

[0052] [Adhesion Layer] The laminate of the present invention may have an adhesion layer. Examples of the adhesion layer include known pressure-sensitive adhesive layers and adhesive layers. The adhesive layer is a layer formed using an adhesive. Examples of adhesives include aqueous adhesives, solvent-based adhesives, emulsion-based adhesives, solventless adhesives, active energy ray-curable adhesives, and heat-curable adhesives. Examples of active energy ray-curable adhesives include electron beam-curable adhesives, ultraviolet light-curable adhesives, and visible light-curable adhesives. The adhesive layer is a layer formed using a pressure-sensitive adhesive. Examples of pressure-sensitive adhesives include rubber-based pressure-sensitive adhesives, acrylic-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, vinyl alkyl ether-based pressure-sensitive adhesives, polyvinyl alcohol-based pressure-sensitive adhesives, polyvinylpyrrolidone-based pressure-sensitive adhesives, polyacrylamide-based pressure-sensitive adhesives, and cellulose-based pressure-sensitive adhesives.

[0053] [Other optically anisotropic layers] The laminate of the present invention may further have other optically anisotropic layers other than the first optically anisotropic film and the second optically anisotropic film. Examples of other optically anisotropic layers include a positive A plate, a negative A plate, a positive C plate, and a negative C plate. The other optically anisotropic layers are appropriately selected according to the desired optical properties. Two or more other optically anisotropic layers may be used.

[0054] [Antireflection Layer] The laminate of the present invention may have an antireflection layer. The antireflection layer is preferably disposed on the outermost surface side of the laminate. The antireflection layer may be disposed on only one surface side of the laminate, or may be disposed on both surfaces of the laminate. Any known antireflection layer can be used as the antireflection layer, and the type is not particularly limited. Among them, a moth-eye film or an AR (antireflection) film is preferred from the viewpoint of further reducing reflectance.

[0055] <Method for producing laminate> The method for producing the laminate of the present invention is not particularly limited as long as it produces a laminate that satisfies the above-mentioned requirements. Examples of the method for producing the laminate of the present invention include the following first, second, and third embodiments.

[0056] A first embodiment of the method for producing a laminate of the present invention includes a method of preparing a first optically anisotropic film that satisfies the above-mentioned requirements, forming a photo-alignment layer on one side of the first optically anisotropic film, applying a liquid crystal composition containing a liquid crystal compound to the side of the photo-alignment layer opposite to the first optically anisotropic film side to form a coating layer L, and performing an alignment treatment on the coating layer L to form a second optically anisotropic film. Each step of the first embodiment will be described in detail below.

[0057] First, a first optically anisotropic film is prepared. The first optically anisotropic film is not particularly limited as long as it satisfies the above-mentioned requirements, and can be produced, for example, by a production method including a stretching step.

[0058] Next, a photo-alignment layer is formed on one side of the first optically anisotropic film. The method for forming the photo-alignment layer is not particularly limited, but examples include a method in which a photo-alignment layer-forming composition containing the components capable of forming the above-mentioned photo-alignment layer is applied to one side of the first optically anisotropic film to form a coating layer P, and then polarized light (preferably linearly polarized light) is irradiated. In this case, it is preferable that the irradiated linearly polarized light is oriented in a direction corresponding to the first anisotropy orientation at each point in the plane of the first optically anisotropic film. For example, when the angle α between the first average orientation and the second average orientation described above is 45°, it is preferable to adjust the direction of the irradiated linearly polarized light so that the angle between the first anisotropy orientation and the second anisotropy orientation at each point of the first optically anisotropic film is 45±1°. The first anisotropy orientation at each point of the first optically anisotropic film can be measured using the above-mentioned method, and the direction of the irradiated linearly polarized light can be adjusted depending on the measured first anisotropy orientation. Furthermore, as will be described in detail later, when the second optically anisotropic film contains a liquid crystal compound with a twisted nematic orientation, the direction of the linearly polarized light to be irradiated may be adjusted so that the angle between the first anisotropic orientation and the second anisotropic orientation is 0±1°.

[0059] An example of adjusting the direction of the irradiated linearly polarized light is to use a linear polarizer as the first optically anisotropic film and irradiate the first optically anisotropic film with unpolarized light from the side opposite to the surface on which the coating layer P is formed. According to the above procedure, linearly polarized light having a polarization direction corresponding to a direction perpendicular to the first anisotropy orientation (the reflection axis direction or absorption axis direction of the linear polarizer) at each point of the first optically anisotropic film is incident on the coating layer P, and a photo-alignment layer having an alignment regulating force in the direction corresponding to the first anisotropy orientation at each point is formed. Another example of adjusting the direction of the irradiated linearly polarized light is to insert a linear polarizer of a predetermined size between a light source that emits unpolarized light and the coating layer P, and irradiate the coating layer P with linearly polarized light. In this case, the orientation of the inserted linear polarizer is adjusted to the direction in which the alignment regulating force of the photo-alignment layer is desired to be generated, and the coating layer P is irradiated with linearly polarized light for each predetermined region. More specifically, a linear polarizer having an area smaller than the area of ​​the coating layer P may be placed between the coating layer P and the light source, and a process of irradiating linearly polarized light through the linear polarizer may be performed while shifting the position of the linear polarizer and changing the polarization direction of the linear polarizer, thereby imparting an orientation control force in a direction corresponding to the first anisotropic orientation at each point.

[0060] Next, a liquid crystal composition containing a liquid crystal compound is applied to the side of the photo-alignment layer opposite to the first optically anisotropic film side to form a coating layer L. The liquid crystal compound contained in the liquid crystal composition can be the liquid crystal compound described above. The liquid crystal composition may also contain the chiral agent described above. The liquid crystal composition may further contain a solvent. Examples of methods for applying the liquid crystal composition include known methods such as roll coating, gravure printing, spin coating, wire bar coating, extrusion coating, direct gravure coating, reverse gravure coating, die coating, spraying, and inkjet printing.

[0061] Next, a treatment is carried out to align the liquid crystal compound in the coating layer L. The alignment treatment aligns the liquid crystal compound along the alignment regulating force of the photo-alignment layer, thereby obtaining a laminate of the present invention that satisfies the above-mentioned formulas (1) and (2). The alignment treatment may include a drying treatment. The drying treatment can remove components such as solvents from the coating layer L. The drying treatment may be carried out by leaving the coating layer L at room temperature for a predetermined time (for example, natural drying), or by heating and / or blowing air. When the drying treatment is carried out at a temperature equal to or higher than the temperature at which the liquid crystal compound contained in the coating layer L transitions from a liquid crystal phase to an isotropic phase, the heating treatment described below may not be carried out.

[0062] The alignment treatment preferably includes a heat treatment, which allows the liquid crystal compound contained in the coating layer L to be aligned. From the viewpoint of manufacturability, the heat treatment is preferably performed at a temperature of 20 to 250°C, more preferably 25 to 190°C. The heating time is preferably 1 to 300 seconds, more preferably 1 to 60 seconds.

[0063] The alignment treatment may include a cooling treatment carried out after the heating treatment. The cooling treatment is a treatment for cooling the coating film after heating. This can fix the alignment of the liquid crystal compound contained in the coating layer L. The cooling method is not particularly limited and can be carried out by a known method. The optimal cooling temperature is selected depending on the liquid crystal compound used.

[0064] When the liquid crystal compound has a polymerizable group, it may be subjected to a curing treatment, such as a light irradiation treatment, if necessary.

[0065] According to the first embodiment described above, a laminate including a photo-alignment layer between a first optically anisotropic film and a second optically anisotropic film is obtained.

[0066] A second embodiment of the laminate manufacturing method of the present invention includes preparing a first optically anisotropic film satisfying the above-mentioned requirements, applying a liquid crystal composition containing a liquid crystal compound to one surface of the first optically anisotropic film to form a coating layer L, and performing an alignment treatment on the coating layer L to form a second optically anisotropic film. The first optically anisotropic film often has molecules of the compound constituting the first optically anisotropic film aligned on its surface according to the first anisotropic orientation at each point in the plane, and thus has an alignment control force. Thus, when a liquid crystal composition is applied to the surface of the first optically anisotropic film to form a coating layer L and an alignment treatment is performed on the coating layer L, the liquid crystal compound is aligned according to the orientation direction of the molecules on the surface of the first optically anisotropic film. In the second embodiment of the laminate of the present invention, the liquid crystal composition preferably contains a chiral agent, and the formed second optically anisotropic film preferably contains a liquid crystal compound with a twisted alignment (more preferably a twisted nematic alignment). When the second optically anisotropic film contains a twisted liquid crystal compound, it is easy to adjust the angle α to satisfy the above-mentioned formula (1). In the second embodiment of the method for producing a laminate of the present invention, the preferred aspects of the method for forming the coating layer L, the alignment treatment, and other treatments are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0067] According to the second embodiment described above, a laminate is obtained in which the first optically anisotropic film is adjacent to the second optically anisotropic film.

[0068] A third embodiment of the laminate manufacturing method of the present invention includes a method in which a first optically anisotropic film satisfying the above-mentioned requirements is prepared and then laminated to a separately obtained second optically anisotropic film. During lamination, the second anisotropic orientation at each point of the second optically anisotropic film and the orientation relationship of the film during lamination are adjusted so as to satisfy the above-mentioned formulas (1) and (2). The second anisotropic orientation at each point of the second optically anisotropic film can be adjusted, for example, by measuring the first anisotropic orientation at each point of the first optically anisotropic film and adjusting it according to the first anisotropic orientation at each point. Examples of adjustment methods include those described in the first embodiment. The first optically anisotropic film and the second optically anisotropic film are laminated, for example, via the above-mentioned adhesive layer. A photo-alignment layer may be used when forming the second optically anisotropic film, and the photo-alignment layer may or may not be removed during lamination. Other than the above points, the method can be carried out in the same manner as in the first and second embodiments, and therefore further explanation is omitted.

[0069] According to the third embodiment described above, a laminate including an adhesive layer between the first optically anisotropic film and the second optically anisotropic film is obtained.

[0070] The laminate obtained by the above-described manufacturing method may be further processed into a non-planar shape. That is, the laminate of the present invention may have a non-planar portion. The entire film of the laminate may be a non-planar portion, or only a portion of the laminate may be a non-planar portion. When only a portion of the laminate is a non-planar portion, the other portion may be a planar portion. The non-planar portion means a portion with a non-planar shape. The non-planar shape means a shape other than a planar shape, such as a curved shape. That is, the non-planar portion may be a curved portion.

[0071] The above-mentioned curved surface shape refers to a shape having a curvature greater than zero, and includes developable curved surface shapes and three-dimensional curved surface shapes. A developable surface is a surface that can be developed into a plane without expanding or contracting any part of the surface. Examples of developable curved surface shapes include surfaces corresponding to cylindrical surfaces, elliptical cylindrical surfaces, conical surfaces, and elliptical conical surfaces, and may be convex or concave curved surfaces. A three-dimensional curved surface refers to a curved surface that cannot be formed by deformation of a plane, i.e., a curved surface that is not developable. Examples of three-dimensional curved surfaces include surfaces corresponding to spherical surfaces and spheroidal surfaces, and surfaces corresponding to curved surfaces whose cross sections form parabolas or hyperbolas (e.g., paraboloids of revolution), and may be convex or concave curved surfaces.

[0072] The curved surface shape is preferably a lens shape. Examples of the lens shape include a spherical shape and a shape of a body of revolution such as a spheroid, and the shape may be a convex lens shape or a concave lens shape.

[0073] When the non-planar portion of the laminate has a curved shape (when the non-planar portion is a curved portion), the radius of curvature of the non-planar portion of the laminate is not particularly limited, but is preferably 20 to 80 mm, more preferably 30 to 80 mm, and even more preferably 35 to 60 mm. The radius of curvature of the non-planar portion of the laminate may be constant or may vary at any position on the non-planar portion, and it is preferable that the radius of curvature at any position is within the above range. When the radius of curvature is constant at any position on the non-planar portion, the shape of the non-planar portion corresponds to a spherical shape.

[0074] When the non-planar portion of the laminate has a curved shape (when the non-planar portion is a curved portion), the minimum radius of curvature of the non-planar portion of the laminate is not particularly limited, but is preferably 30 to 80 mm, more preferably 35 to 60 mm, in terms of better effects of the present invention. When the non-planar portion of the laminate has a curved shape (when the non-planar portion is a curved portion), the maximum radius of curvature of the non-planar portion of the laminate is not particularly limited, but is preferably 35 to 80 mm, more preferably 35 to 60 mm.

[0075] When the curved surface shape of the non-planar portion of the laminate is a solid of revolution such as a spherical shape, a spheroidal shape, or a paraboloidal shape, the size of the non-planar portion when viewed from above in the direction of the axis of rotation of these shapes is not particularly limited, and the equivalent circle diameter of the non-planar portion is preferably 30 to 80 mm, more preferably 40 to 60 mm. The equivalent circle diameter is the diameter of a perfect circle having the same projected area as the projected area of ​​the non-planar portion when observed.

[0076] <Display Device (Virtual Reality Display Device)> The laminate of the present invention is applicable to various display devices, and is preferably applied to a virtual reality display device. FIG. 4 is a schematic diagram showing an example of the configuration of a virtual reality display device. The virtual reality display device 40 shown in FIG. 4 has, from the right side in the figure, an image display panel 42, a circular polarizing plate 44, a half mirror 46, and a laminate 10 of the present invention. The laminate 10 used in FIG. 4 has the same configuration as the laminate 10 shown in FIG. 1, and the laminate 10 functions as a reflective circular polarizer. That is, in the embodiment shown in FIG. 4, the first optically anisotropic film 12 is a reflective linear polarizer, the second optically anisotropic film 14 functions as a λ / 4 plate, and the above-mentioned angle α is 45°. The laminate 10 used in FIG. 4 is a member that has been cut out from the laminate of the present invention to fit the shape of the virtual reality display device 40.

[0077] In the virtual reality display device 40 shown in FIG. 4 , light emitted from the image display panel 42 passes through a circular polarizer 44 to become circularly polarized light, a portion of which passes through a half mirror 46. The circularly polarized light that passes through the half mirror 46 enters the second optically anisotropic film 14 included in the laminate 10 of the present invention, where it is converted to linearly polarized light and reflected by the first optically anisotropic film 12 (reflective linear polarizer). The linearly polarized light reflected by the first optically anisotropic film 12 passes through the second optically anisotropic film 14 to become circularly polarized again and is reflected by the half mirror 46. When the circularly polarized light is reflected by the half mirror 46, its phase is reversed, so the rotation direction of the circularly polarized light reflected by the half mirror 46 is reversed from before reflection. The circularly polarized light reflected by the half mirror 46 and with its rotation direction reversed enters the laminate 10 again. The circularly polarized light that re-enters the laminate 10 is rotated in the opposite direction to the circularly polarized light reflected by the laminate 10, and therefore, when it undergoes polarization conversion by the second optically anisotropic film 14, it is converted into linearly polarized light that is transmitted through the first optically anisotropic film 12. Therefore, the light reflected by the half mirror 46 passes through the laminate 10 and is visible to the user. In the virtual reality display device 40, the optical characteristics resulting from the relationship of formula (1) are similarly satisfied at each position of the specific position group within the region X in the laminate (laminate 10) of the present invention, and therefore the generation of light that passes through the first optically anisotropic film 12 is suppressed, as indicated by the dashed arrow in Figure 4, and as a result, the generation of ghosts is suppressed.

[0078] The image display panel 42 is a known image display panel (display panel) such as an organic electroluminescence display panel. In the example shown in Fig. 4, the image display panel 42 emits an unpolarized image (image light). The unpolarized image emitted by the image display panel 42 passes through the circular polarizer 44 and is converted into circularly polarized light. Note that the image display panel 42 may also emit linearly polarized light, in which case a λ / 4 plate may be used instead of the circular polarizer 44.

[0079] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment details, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[0080] <Production of Laminate of Example 1> A laminate S1 (circularly polarizing plate) of Example 1 was obtained by the following procedure.

[0081] [First Optically Anisotropic Film] The first optically anisotropic film (reflective linear polarizer R1) was obtained according to the method described in U.S. Pat. No. 5,882,774. As mentioned above, the reflective linear polarizer R1 is also available from 3M under the trade name APF. The first anisotropy orientation and the first average orientation at specific positions (points A to I, see FIG. 2 ) within a 50 cm x 50 cm square region X of the reflective linear polarizer R1, measuring 52 cm x 52 cm, were evaluated using an AxoScan (polarimeter) device from Axometrics. The results are shown in the table below.

[0082] [Second optically anisotropic film] A cellulose acylate film was prepared according to the following procedure, a photo-alignment layer was formed on the prepared cellulose acylate film, a liquid crystal composition was applied onto the formed photo-alignment layer, and an alignment treatment and a curing treatment were performed to form a second optically anisotropic film.

[0083] (Preparation of Cellulose Acylate Film T1) - Preparation of Core Layer Cellulose Acylate Dope - The following composition was charged into a mixing tank and stirred to dissolve each component, thereby preparing a cellulose acetate solution to be used as a core layer cellulose acylate dope.

[0084] ─────────────────────────────────── Core Layer Cellulose Acylate Dope ───────────────────────────────── Cellulose acetate having an acetyl substitution degree of 2.88: 100 parts by mass Polyester compound B described in the examples of JP-A No. 2015-227955: 12 parts by mass Compound G below: 2 parts by mass Methylene chloride (first solvent): 430 parts by mass Methanol (second solvent): 64 parts by mass ───────────────────────────────

[0085] Compound G

[0086] - Preparation of outer layer cellulose acylate dope - 10 parts by mass of the following matting agent solution was added to 90 parts by mass of the above core layer cellulose acylate dope to prepare a cellulose acetate solution to be used as the outer layer cellulose acylate dope. ─────────────────────────────────────Matting agent solution───────────────────────────────── - Silica particles having an average particle size of 20 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass - Methylene chloride (first solvent) 76 parts by mass - Methanol (second solvent) 11 parts by mass - The above core layer cellulose acylate dope 1 part by mass ─────────────────────────────────

[0087] -Casting of Cellulose Acylate Film T1- The core layer cellulose acylate dope and the outer layer cellulose acylate dope were filtered through a filter paper with an average pore size of 34 μm and a sintered metal filter with an average pore size of 10 μm. After filtration, the core layer cellulose acylate dope and the outer layer cellulose acylate dopes on both sides of it were simultaneously cast onto a drum at 20°C from a casting nozzle (band caster). After casting, the film was peeled off from the drum with a solvent content of approximately 20% by mass, and both ends of the film in the width direction were fixed with tenter clips. It was then stretched in the transverse direction at a stretch ratio of 1.1 times while being dried. It was then further dried by transporting it between the rolls of a heat treatment device to produce a 40 μm-thick cellulose acylate film T1. The core layer of the cellulose acylate film T1 had a thickness of 36 μm, and the outer layers on both sides of the core layer each had a thickness of 2 μm. The in-plane retardation of the resulting cellulose acylate film T1 was 0 nm.

[0088] (Preparation of Photo-Alignment Layer 1) A composition PM-1 for forming a photo-alignment layer was prepared with reference to Example 3 of JP2012-155308A, and applied to the cellulose acylate film T1 using a wire bar. The resulting film was dried with hot air at 60°C for 60 seconds to form a coating layer P1 having a thickness of 300 nm.

[0089] The prepared coating layer P1 was irradiated with ultraviolet light using an ultra-high pressure mercury lamp under atmospheric pressure. At this time, a wire grid polarizer (ProFlux PPL02, manufactured by Moxtek) was placed between the lamp and the coating layer P1 so as to be parallel to the coating layer P1, and ultraviolet light was irradiated. A photo-alignment treatment was then performed to form a photo-alignment layer 1. The photo-alignment treatment was performed on the coating layer P1 in a region that will overlap with the region X of the reflective linear polarizer R1 when they are bonded in a later process. Specifically, the orientation of the transmission axis of the wire grid polarizer was adjusted so that the polarization direction of the ultraviolet light irradiated at each point on the corresponding region on the coating layer P1 side was oriented at -45° (45° counterclockwise with respect to the first anisotropy orientation) relative to the first anisotropy orientation at each point in the region X of the reflective linear polarizer R1. This was sequentially performed for each 20 cm x 20 cm region. The illuminance of the ultraviolet light used for exposure is 10 mJ / cm in the UV-A region (ultraviolet A rays, wavelength 320 to 380 nm).２ When the optically anisotropic layer Q1 described later is formed using the photo-alignment layer 1 obtained by the above procedure, the anisotropy orientation of the optically anisotropic layer Q1 is an orientation of +90° (45° clockwise from the first anisotropy orientation) with respect to the polarization direction of the ultraviolet light irradiated during the alignment treatment of the photo-alignment layer 1.

[0090] (Formation of Optically Anisotropic Layer Q1) —Preparation of Coating Liquid A1 for Forming Positive A Plate— Coating liquid A1 for forming a positive A plate having the following composition was prepared. -------------------------------- Composition of coating liquid A1 for forming positive A plate------------------------------------------------ - 16.00 parts by mass of polymerizable liquid crystal compound X-1 below - 42.00 parts by mass of liquid crystal compound L-1 below - 42.00 parts by mass of liquid crystal compound L-2 below - 0.50 parts by mass of polymerization initiator S-1 below - 4.00 parts by mass of acid anhydride K-1 below - 2.00 parts by mass of polymerizable compound B-1 below - 0.20 parts by mass of leveling agent (compound T-1 below) - 230.00 parts by mass of methyl ethyl ketone (solvent) - 70.00 parts by mass of cyclopentanone (solvent)--------------------------------

[0091] Polymerizable liquid crystal compound X-1, liquid crystal compound L-1, liquid crystal compound L-2, and compound T-1

[0092] Polymerization initiator S-1

[0093] Acid anhydride K-1

[0094] Polymerizable compound B-1

[0095] Next, a coating layer was formed by applying the coating solution A1 for forming a positive A plate using a bar coater onto the photo-alignment-treated photo-alignment layer 1. The coating layer was heated and aged for 20 seconds so that the film surface temperature reached 100°C, and then cooled to 90°C for alignment treatment. After the alignment treatment, an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) was used in air to irradiate the coating solution A1 with 300 mJ / cm. ２ After the optically anisotropic layer Q1 was formed, the cellulose acylate film T1 on which the optically anisotropic layer Q1 was laminated was trimmed to a size of 52 cm x 52 cm by cutting off unnecessary portions, leaving only the region that had been subjected to polarized light exposure in the photo-alignment treatment and that corresponds to region X.

[0096] The optically anisotropic layer Q1 formed on one surface of the cellulose acylate film T1 had a film thickness of 2.4 μm. The optically anisotropic layer Q1 was measured for the light incident angle dependence of Re (in-plane retardation) and the tilt angle of the optical axis using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.). The measurement results showed that Re was 145 nm and Rth was 73 nm at a wavelength of 550 nm. Furthermore, Re(450) / Re(550) was 0.81, and Re(650) / Re(550) was 1.01. The tilt angle of the optical axis was 0°, and the liquid crystal compound was homogeneously aligned (horizontally aligned). The second anisotropy orientation and the second average orientation at each of the specific positions (positions A to I, see FIG. 2) in the region X were evaluated using an Axometrics AxoScan (polarimeter) device. The direction of the slow axis (second anisotropy orientation) at each measurement point in the region X is shown in the table below.

[0097] [Adhesive-attached film 1] Adhesive N1 was prepared with reference to the description in Example 1 of JP 2017-134414 A, and adhesive-attached film 1 was obtained.

[0098] [Preparation of Laminate (Circular Polarizing Plate)] The reflective linear polarizer R1 and the cellulose acylate film T1 having the optically anisotropic layer Q1 formed thereon were bonded together using the pressure-sensitive adhesive N1, with one surface of the reflective linear polarizer R1 facing the optically anisotropic layer Q1. After bonding, the optically anisotropic layer Q1 and the photo-alignment layer 1 were peeled off at the interface between them, and the photo-alignment layer 1 and the cellulose acylate film T1 were removed from the bonded product. Using the above procedure, a reflective circular polarizer C1 having the reflective linear polarizer R1 (first optically anisotropic film) and the optically anisotropic layer Q1 (second optically anisotropic film) was obtained. Furthermore, an antireflection layer was formed on the surface of the reflective circular polarizer C1 obtained using the above procedure, facing the optically anisotropic layer Q1, to obtain the laminate S1 of Example 1. The antireflection layer was formed by bonding a "g-moth" antireflection film manufactured by Geomatec Co., Ltd. The angle between the first anisotropy orientation (reflection axis direction) of the reflective linear polarizer R1 and the second anisotropy orientation (in-plane slow axis direction) of the optically anisotropic layer Q1 at each position of the specific position group within region X of the obtained laminate S1 is shown in the table below.

[0099] <Production of Laminate of Example 2> A laminate S2 (circularly polarizing plate) of Example 2 was obtained by the following procedure.

[0100] [First Optically Anisotropic Film] A first optically anisotropic film (reflective linear polarizer R1) similar to that in Example 1 was prepared.

[0101] [Second optically anisotropic film] A photo-alignment layer was formed on a reflective linear polarizer R1 according to the following procedure, a liquid crystal composition was applied to the formed photo-alignment layer, and an alignment treatment and a curing treatment were performed to form a second optically anisotropic film.

[0102] (Preparation of Photo-Alignment Layer 2 on First Optically Anisotropic Film) One surface of a reflective linear polarizer R1 was subjected to a corona treatment, and the above-described composition for forming a photo-alignment layer PM-1 was applied to the treated surface with a wire bar. The applied surface was dried with hot air at 60°C for 60 seconds to form a coating layer P2 with a thickness of 300 nm.

[0103] The prepared coating layer P2 was irradiated with ultraviolet light using an ultra-high pressure mercury lamp under atmospheric pressure. At this time, a wire grid polarizer (ProFlux PPL02, manufactured by Moxtek) was placed between the lamp and the coating layer P2 so as to be parallel to the coating layer P2, and ultraviolet light was irradiated. A photo-alignment treatment was then performed to form a photo-alignment layer 2. The photo-alignment treatment was performed on the coating layer P2 in the region overlapping with the region X of the reflective linear polarizer R1. Specifically, the orientation of the transmission axis of the wire grid polarizer was adjusted sequentially for each 20 cm x 20 cm region so that the polarization direction of the ultraviolet light irradiated at each corresponding point on the photo-alignment layer P2 side was oriented at -45° relative to the first anisotropy orientation at each point in the region X of the reflective linear polarizer R1. The illuminance of the ultraviolet light used for exposure was 10 mJ / cm in the UV-A region (ultraviolet A rays, wavelength 320 to 380 nm). ２ When the optically anisotropic layer Q2 described later is formed using the photo-alignment layer 2 obtained by the above procedure, the anisotropy direction of the optically anisotropic layer Q2 is at an angle of +90° with respect to the polarization direction of the ultraviolet light irradiated during the alignment treatment of the photo-alignment layer 2.

[0104] (Formation of Optically Anisotropic Layer Q2) The coating solution A1 for forming a positive A plate was applied to the photo-aligned photo-alignment layer 2 using a bar coater to form a coating layer. The coating layer was heated and aged for 20 seconds so that the film surface temperature reached 100°C, and then cooled to 90°C for alignment treatment. After the alignment treatment, the coating layer was aged in air at 300 mJ / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.). ２ The film was irradiated with ultraviolet light of 1000 kJ / cm, and the alignment state was fixed to form an optically anisotropic layer Q2 (second optically anisotropic film). The above procedure resulted in a reflective circular polarizer C2 having a reflective linear polarizer R1 (first optically anisotropic film), a photo-alignment layer 2, and an optically anisotropic layer Q2 (second optically anisotropic film). The film thickness of the optically anisotropic layer Q2 was 2.4 μm.

[0105] The optically anisotropic layer Q2 was peeled off and transferred onto a glass substrate, and its optical properties were evaluated. The optically anisotropic layer Q2 was measured for the light incident angle dependence of Re (in-plane retardation) and the tilt angle of the optical axis using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.). The measurement results showed that Re was 145 nm and Rth was 73 nm at a wavelength of 550 nm. Furthermore, Re(450) / Re(550) was 0.81, and Re(650) / Re(550) was 1.01. The tilt angle of the optical axis was 0°, and the liquid crystal compound was homogeneously aligned (horizontally aligned). The second anisotropic orientation and second average orientation at each position (positions A to I, see FIG. 2 ) of the specific position group within region X were evaluated using an AxoScan (polarimeter) device from Axometrics. The direction of the slow axis (second anisotropy direction) at each measurement point in region X is shown in the table below.

[0106] An antireflection layer was formed on the surface of the reflective circular polarizer C2 obtained by the above procedure on the side of the optically anisotropic layer Q2, to give a laminate S2 of Example 2. The antireflection layer was formed by laminating "g-moth" manufactured by Geomatec Co., Ltd. as an antireflection film. The angle between the first anisotropy orientation (reflection axis direction) of the reflective linear polarizer R1 and the second anisotropy orientation (in-plane slow axis direction) of the optically anisotropic layer Q2 at each position of the specific position group within region X of the obtained laminate S2 is shown in the table below.

[0107] <Production of Laminate of Example 3> A laminate S3 (circularly polarizing plate) of Example 3 was obtained by the following procedure.

[0108] [First Optically Anisotropic Film] A first optically anisotropic film (reflective linear polarizer R1) similar to that in Example 1 was prepared.

[0109] [Second Optically Anisotropic Film] A liquid crystal composition was directly applied onto the reflective linear polarizer R1, followed by an alignment treatment and a curing treatment, to form a second optically anisotropic film, according to the following procedure.

[0110] (Formation of Optically Anisotropic Layer Q3 on First Optically Anisotropic Film) —Preparation of Coating Solution A2 for Forming Twisted Nematic Layer— Coating Solution A2 for forming twisted nematic layer having the following composition was prepared. -------------------------------- Composition of Coating Solution A2 for Forming Twisted Nematic Layer------------------------------------------------ - 16.00 parts by mass of the polymerizable liquid crystal compound X-1 - 42.00 parts by mass of the liquid crystal compound L-1 - 42.00 parts by mass of the liquid crystal compound L-2 - 0.50 parts by mass of the polymerization initiator S-1 - 4.00 parts by mass of the acid anhydride K-1 - 2.00 parts by mass of the polymerizable compound B-1 - 0.30 parts by mass of the following chiral agent CH-1 - 0.20 parts by mass of the leveling agent (compound T-1) - 230.00 parts by mass of methyl ethyl ketone (solvent) - 70.00 parts by mass of cyclopentanone (solvent)--------------------------------

[0111] Chiral agent CH-1

[0112] - Formation of Optically Anisotropic Layer Q3 - One surface of the reflective linear polarizer R1 was subjected to a corona treatment, and the twisted nematic forming coating solution A2 was applied to the treated surface using a bar coater to form a coating layer. The coating layer was heated and aged for 20 seconds so that the film surface temperature reached 100°C, and then cooled to 90°C for alignment treatment. Note that the above procedure aligns the liquid crystal compound in a direction corresponding to the first anisotropic orientation at each point of the reflective linear polarizer R1. After the alignment treatment, the layer was irradiated with 300 mJ / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under air. ２The film was irradiated with ultraviolet light of 1000 kJ / cm, and the alignment state was fixed to form an optically anisotropic layer Q3 (second optically anisotropic film). The above procedure resulted in a reflective circular polarizer C3 having a reflective linear polarizer R1 (first optically anisotropic film) and an optically anisotropic layer Q3 (second optically anisotropic film). The film thickness of the optically anisotropic layer Q3 was 3.2 μm.

[0113] The optically anisotropic layer Q3 was peeled off and transferred onto a glass substrate, and evaluated using an Axometrics AxoScan (polarimeter) device. The liquid crystal compound had a twisted nematic orientation, with a twist angle of 64°. That is, in the optically anisotropic layer Q3, the orientation direction of the liquid crystal compound on one surface rotated 64° around the direction toward the other surface as the helical axis. Twisted nematic films with a twist angle of 180° or less behave as retardation films. The anisotropic orientation of the optically anisotropic layer Q3 as a retardation film was evaluated using an Axometrics AxoScan (polarimeter) device, also from Axometrics, at each of the specific positions within Region X (Positions A to I, see Figure 2). The direction of the slow axis (second anisotropy orientation) at each measurement point in Region X is shown in the table below.

[0114] An antireflection layer was formed on the surface of the reflective circular polarizer C3 obtained by the above procedure on the side of the optically anisotropic layer Q3, to give a laminate S3 of Example 3. The antireflection layer was formed by laminating a "g-moth" manufactured by Geomatec Co., Ltd. as an antireflection film. The angle between the first anisotropy orientation (reflection axis direction) of the reflective linear polarizer R1 and the second anisotropy orientation (in-plane slow axis direction) of the optically anisotropic layer Q3 at each position of the specific position group within region X of the obtained laminate S3 is shown in the table below.

[0115] <Production of Laminate of Example 4> A laminate S4 (circularly polarizing plate) of Example 4 was obtained by the following procedure.

[0116] [First Optically Anisotropic Film] A first optically anisotropic film (reflective linear polarizer R1) similar to that in Example 1 was prepared.

[0117] [Second optically anisotropic film] A photo-alignment layer was formed on a reflective linear polarizer R1 according to the following procedure, a liquid crystal composition was applied to the formed photo-alignment layer, and an alignment treatment and a curing treatment were performed to form a second optically anisotropic film.

[0118] (Preparation of Photo-Alignment Layer 4 on First Optically Anisotropic Film) One surface of the reflective linear polarizer R1 was subjected to a corona treatment, and the above-described composition for forming a photo-alignment layer PM-1 was applied to the treated surface with a wire bar. The applied surface was dried with hot air at 60°C for 60 seconds to form a coating layer P4 with a thickness of 300 nm.

[0119] Next, the resulting coating layer P4 was exposed to ultraviolet light (illuminance 4.5 mW, irradiation dose 50 mJ / cm) using an ultraviolet light exposure device in a manner that exposed it from the reflective linear polarizer side. ２ ) was irradiated onto the coating layer P4 to prepare a photo-alignment layer 4. The coating layer P4 was irradiated with ultraviolet light that had passed through the reflective linear polarizer R1. In the above procedure, ultraviolet light having a polarization direction corresponding to the first anisotropic orientation at each point of the reflective linear polarizer R1 was transmitted.

[0120] (Formation of Optically Anisotropic Layer Q4) The twisted nematic forming coating solution A2 was applied with a bar coater onto the photo-aligned photo-alignment layer 4 to form a coating layer. The coating layer was heated and aged for 20 seconds so that the film surface temperature reached 100°C, and then cooled to 90°C for alignment treatment. After the alignment treatment, the layer was irradiated with 300 mJ / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under air. ２ The alignment state was fixed by irradiating ultraviolet light of 1000 kJ / cm 2 to form an optically anisotropic layer Q4 (second optically anisotropic film). The above procedure resulted in a reflective circular polarizer C4 having a reflective linear polarizer R1 (first optically anisotropic film), a photo-alignment layer 4, and an optically anisotropic layer Q4 (second optically anisotropic film). The film thickness of the optically anisotropic layer Q4 was 3.2 μm.

[0121] The optically anisotropic layer Q4 was peeled off and transferred onto a glass substrate, and evaluated using an Axometrics AxoScan (polarimeter) device. The liquid crystal compound had a twisted nematic orientation, with a twist angle of 64°. Twisted nematic films with a twist angle of 180° or less behave as retardation films. The anisotropic orientation of the optically anisotropic layer Q4 as a retardation film was evaluated using an Axometrics AxoScan (polarimeter) device at each of the specific positions (positions A to I, see Figure 2) in region X, measuring the second anisotropy orientation and second average orientation. The direction of the slow axis (second anisotropy orientation) at each measurement point in region X is shown in the table below.

[0122] An antireflection layer was formed on the surface of the reflective circular polarizer C4 obtained by the above procedure on the side of the optically anisotropic layer Q4, to give a laminate S4 of Example 4. The antireflection layer was formed by laminating a "g-moth" manufactured by Geomatec Co., Ltd. as an antireflection film. The angle between the first anisotropy orientation (reflection axis direction) of the reflective linear polarizer R1 and the second anisotropy orientation (in-plane slow axis direction) of the optically anisotropic layer Q4 at each position of the specific position group within region X of the obtained laminate S4 is shown in the table below.

[0123] <Production of the laminate of Comparative Example 1> In the production procedure for the laminate of Example 1, an optically anisotropic layer QC1 was formed using the same procedure as in Example 1, except that linearly polarized light was uniformly irradiated onto the entire surface of the coating layer P1 so that the angle α between the first average orientation and the second average orientation was 45° after bonding, and the reflective linear polarizer R1 and the optically anisotropic layer QC1 were bonded to obtain the laminate SC1 of Comparative Example.

[0124] <Fabrication of Virtual Reality Display Device> A virtual reality display device "VIVE FLOW" manufactured by HTC was disassembled, and optical lenses were removed. The "VIVE FLOW" is a virtual reality display device that employs pancake lenses, and its image display device uses a liquid crystal display device that emits circularly polarized light using a polarizing plate attached to its surface. The optical lenses removed were a biconvex lens with a half-mirror coating on one side, and a plano-convex lens with an optical laminate attached to its flat surface. The optical laminate on the flat surface side of the plano-convex lens was removed, and a laminate S1 punched to a size that matched the lens was attached instead. The laminate S1 was attached so that the reflective linear polarizer R1 side of the laminate S1 was positioned on the flat surface side of the plano-convex lens. The plano-convex lens attached with the laminate S1 was incorporated into the original virtual reality display device, and virtual reality display device V1 using the laminate S1 was fabricated. Similarly, virtual reality display devices V2 to V4 and VC1 using laminates S2 to S4 and SC1 were also fabricated.

[0125] <Evaluation> For each virtual reality display device obtained by the above procedure, a black and white checkered pattern was displayed on the image display device, and the occurrence of ghosting was evaluated based on the following evaluation criteria. Note that ghosting occurs when there is light leakage from the laminate, and in the case of a black and white checkered pattern, the occurrence of ghosting corresponds to the appearance of double or multiple images at the boundary between the white and black of the checkered pattern. A: No double image is visible, or it is slightly visible but not bothersome. B: An easily noticeable double image is visible, which interferes with viewing.

[0126] The above evaluation was carried out using laminates punched out from portions corresponding to the respective positions of the specific position group within the region X.

[0127] <Results> The first anisotropic orientation and second anisotropic orientation, as well as the first average orientation and second average orientation at each position of the specific position group within region X of the laminate of each example and comparative example, are shown in Table 1. In addition, the results of the above evaluation performed on members cut out from the laminate in the portion corresponding to each position of the specific position group are shown in Table 1. In addition, the "γ" column in Table 1 indicates the angle between the first anisotropic orientation and the first average orientation at each position of the specific position group.

[0128]

[0129] From the results shown in Table 1, even when a first optically anisotropic film is used in which the maximum value of the angle between the first average orientation and the first anisotropic orientation in the above-mentioned region X (see the "γ" column in Table 1) is within the range of 0.5 to 5.0°, when a laminate is used in which the second anisotropic orientation of the second optically anisotropic film is adjusted to satisfy the relationship of the above-mentioned formula (2) at each position of the specific position group (see the "absolute value of β-α" column in Table 1), it was confirmed that when applied to a head-mounted display, it is possible to cut out more components that suppress the generation of ghosts. On the other hand, when a laminate was obtained using a second optically anisotropic film that does not satisfy the relationship of the above-mentioned formula (2) (see the "absolute value of β-α" column in Table 1), many components that generate ghosts were cut out.

[0130] REFERENCE SIGNS LIST 10 Laminate 12 First optically anisotropic film 14 Second optically anisotropic film 40 Virtual reality display device 42 Image display panel 44 Circular polarizer 46 Half mirror

Claims

1. A laminate comprising a first optically anisotropic film and a second optically anisotropic film, wherein a first average orientation is an average orientation of a direction in which the optical anisotropy of the first optically anisotropic film is maximized at each position of a specific position group consisting of positions corresponding to each vertex of the square, the midpoint positions of each side of the square, and the center of gravity position of the square in a 50 cm x 50 cm square area X on the plane of the laminate, and a second average orientation is an average orientation of a direction in which the optical anisotropy of the second optically anisotropic film is maximized at each position of the specific position group in the area X, the maximum value of the angle between the direction in which the optical anisotropy of the first optically anisotropic film is maximized at each position of the specific position group and the first average orientation is within a range of 0.5 to 5.0°, and an angle α between the first average orientation and the second average orientation satisfies the relationship of formula (1), A laminate, in which, when an angle β is defined as an angle between a direction in which the optical anisotropy of the first optically anisotropic film is maximized and a direction in which the optical anisotropy of the second optically anisotropic film is maximized at any position in the region X, the angle β at each position in the specific position group satisfies the relationship of formula (2). Formula (1) 10°<α<80° Formula (2) 0°≦|β-α|<1° 2. The laminate according to claim 1, which is in a long shape.

3. The laminate according to claim 2, wherein the first average orientation is at an angle of 80 to 100° with respect to the longitudinal direction of the elongated shape.

4. The laminate according to any one of claims 1 to 3, wherein the first optically anisotropic film is a stretched film.

5. The laminate according to any one of claims 1 to 3, wherein the first optically anisotropic film is a reflective linear polarizer.

6. The laminate according to any one of claims 1 to 3, wherein the second optically anisotropic film has an in-plane retardation of 110 to 170 nm at a wavelength of 550 nm.

7. A laminate according to any one of claims 1 to 3, wherein the angle α is 43 to 47 degrees.

8. The laminate according to any one of claims 1 to 3, wherein the second optically anisotropic film contains an oriented liquid crystal compound.

9. The laminate according to any one of claims 1 to 3, wherein the second optically anisotropic film contains a liquid crystal compound in a twisted nematic orientation.

10. The laminate according to any one of claims 1 to 3, wherein the first optically anisotropic film is adjacent to the second optically anisotropic film.

11. The laminate according to any one of claims 1 to 3, further comprising a photoalignment layer between the first optically anisotropic film and the second optically anisotropic film.

12. A display device comprising the laminate according to any one of claims 1 to 3.

13. The display device of claim 12 which is a virtual reality display device.

14. A rolled body obtained by rolling up the laminate according to any one of claims 1 to 3, which is in a long shape.

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