Laminate, composite lens, goggle-type display device, and method for producing laminate

Abstract

The present invention addresses the problem of providing: a laminate which is capable of suppressing the occurrence of ghosts when used in a goggle-type display device; a composite lens; a goggle-type display device; and a method for producing a laminate. A laminate according to the present invention has a curved surface part, and comprises a light absorption anisotropic film and a light reflection anisotropic film. The light absorption anisotropic film satisfies formula (3) and at least one of formulae (1) and (2).　Formula (1): Tm(peak top) ≥ 205°C; Formula (2): ∆Hm ≥ 100 mJ / mg; Formula (3): Sa ≤ 20 nm. In the formulae, Tm(peak top) represents the peak top temperature of the endothermic peak of the DSC curve obtained when the temperature is raised from 25°C to 300°C at a rate of 10°C / minute in differential scanning calorimetry. ∆Hm represents the melting heat quantity of the endothermic peak of the DSC curve obtained when the temperature is raised from 25°C to 300°C at a rate of 10°C / minute in differential scanning calorimetry. Sa represents an arithmetic mean height.

Description

Laminate, composite lens, goggle-type display device, and method for manufacturing laminate

[0001] The present invention relates to a laminate, a composite lens, a goggle-type display device, and a method for manufacturing the laminate.

[0002] In recent years, as the applications of polarizing plates have become more diverse, there has been a demand for providing polarizing plates on articles with curved surfaces rather than flat surfaces, depending on the application.

[0003] For example, Patent Document 1 describes "a polarizing plate including a polarizer and a protective layer disposed on at least one side of the polarizer, which is curved, and the breaking elongation E per unit thickness of the polarizer is 0.25 (% / μm) or more" ([Claim 1]). It also describes "a method for producing a curved polarizing plate, which includes: preparing a polarizing plate including a polarizer and a protective layer disposed on at least one side of the polarizer; heating the polarizing plate together with a mold having a predetermined curved shape to curve it; and humidifying the curved polarizing plate in an environment of 40° C. to 65° C. and 85% RH to 95% RH for 40 minutes or more" ([Claim 5]).

[0004] Japanese Patent Application Laid-Open No. 2022-75143

[0005] The inventors have found that when a laminate having an optically absorbing anisotropic film and an optically reflective anisotropic film is subjected to curved processing using the method described in Patent Document 1 to provide a curved surface portion, ghosts may be visible when the laminate having the curved surface portion thus produced is used in a goggle-type display device (e.g., a virtual reality display device, etc.).

[0006] Therefore, another object of the present invention is to provide a laminate, a composite lens, a goggle-type display device, and a method for manufacturing the laminate, which can suppress the occurrence of ghosts when used in a goggle-type display device.

[0007] As a result of intensive research to achieve the above object, the present inventors have found that, in a laminate having an optically absorptive anisotropic film and an optically reflective anisotropic film, if the optically absorptive anisotropic film satisfies at least one of formulas (1) and (2) described below and formula (3) described below, the occurrence of ghost images can be suppressed when the laminate is used in a goggle-type display device, and have completed the present invention. That is, the present inventors have found that the above object can be achieved by the following configuration.

[0008] [1] A laminate having a curved surface, the laminate comprising an optically absorptive anisotropic film and an optically reflective anisotropic film, wherein the optically absorptive anisotropic film satisfies at least one of the following formulas (1) and (2), and the following formula (3): Formula (1): Tm (peak top) ≧ 205°C Formula (2): ΔHm ≧ 100 mJ / mg Formula (3): Sa ≦ 20 nm wherein, in formulas (1) to (3), Tm (peak top) represents the peak-top temperature of the endothermic peak in the DSC curve obtained when the temperature is raised from 25°C to 300°C at 10°C / min in differential scanning calorimetry; ΔHm represents the heat of solution of the endothermic peak in the DSC curve obtained when the temperature is raised from 25°C to 300°C at 10°C / min in differential scanning calorimetry; and Sa represents the arithmetic mean height. [2] The laminate according to [1], wherein the curved portion has a non-developable curved surface. [3] The laminate according to [1] or [2], wherein the smallest curvature of the curved portion is 50 mm or less. [4] The laminate according to any one of [1] to [3], wherein the light-reflecting anisotropic film is a linear polarization type reflective polarizer that reflects one of mutually orthogonal linearly polarized light beams and transmits the other linearly polarized light beam. [5] The laminate according to any one of [1] to [4], further comprising a resin lens, wherein the resin lens has a curved portion and a maximum thickness of 3 mm or more. [6] The laminate according to any one of [1] to [5], wherein the light-absorbing anisotropic film is a polyvinyl alcohol-based resin film containing iodine. [7] The laminate according to any one of [1] to [6], wherein the light-absorbing anisotropic film has a thickness of 8 μm or less. [8] The laminate according to any one of [1] to [7], further comprising a retardation layer. [9] A composite lens having, in this order, the laminate according to any one of [1] to [8], a lens, and a half mirror.

[10] A goggle-type display device having the laminate according to any one of [1] to [8] or the composite lens according to [9].

[11] A method for producing a laminate according to any one of [1] to [8], the method comprising a curved surface processing step of forming a curved surface portion by performing curved surface processing at 170°C or higher.

[12] A method for producing the laminate according to

[11] , the method comprising, after the curved surface processing step, a slow cooling step of cooling at a cooling rate of 3°C / min or less.

[13] The method for producing a laminate according to

[11] or

[12] , comprising a humidification treatment step of carrying out humidification treatment for 30 minutes or less in an environment of a temperature of 40 to 65°C and a relative humidity of 85 to 95% after the curved surface processing step.

[0009] According to the present invention, it is possible to provide a laminate, a composite lens, a goggle-type display device, and a method for manufacturing the laminate, which are capable of suppressing the occurrence of ghosts when used in a goggle-type display device.

[0010] FIG. 1 is a top view showing an example of a laminate of the present invention. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is a cross-sectional view showing another example of a laminate of the present invention. FIG. 4 is a cross-sectional view showing another example of a laminate of the present invention. FIG. 5 is a diagram illustrating the procedure for molding a film using a mold having a concave molding surface. FIG. 6 is a diagram illustrating the procedure for molding a film using a mold having a concave molding surface. FIG. 7 is a top view of a film used for molding. FIG. 8 is a diagram illustrating the procedure for molding a film using a mold having a convex molding surface. FIG. 9 is a diagram illustrating the procedure for molding a film using a mold having a convex molding surface. FIG. 10 is a cross-sectional view showing an example of a composite lens of the present invention. FIG. 11 is a diagram showing an example of a goggle-type display device of the present invention, illustrating an example of light rays of a main image. FIG. 12A is a process diagram illustrating an example of manufacturing a laminate of the present invention by in-mold molding. FIG. 12B is a process diagram illustrating an example of manufacturing a laminate of the present invention by in-mold molding. FIG. 12C is a process diagram illustrating an example of manufacturing the laminate of the present invention by in-mold molding.

[0011] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments and specific examples, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the upper and lower limits. In this specification, the upper or lower limit of a numerical range described in stages may be replaced with the upper or lower limit of another numerical range described in stages. In this specification, the upper or lower limit of a numerical range described in stages may be replaced with a value shown in the Examples. In this specification, each component may be a single substance corresponding to the component, or two or more substances may be used in combination. When two or more substances are used in combination for each component, the content of that component refers to the total content of the substances used in combination, unless otherwise specified.

[0012] In this specification, the term "transmittance" refers to the average transmittance in the wavelength range of 380 to 780 nm.

[0013] In this specification, "absorption axis" refers to the polarization direction in which absorbance is maximized in a plane when linearly polarized light is incident. "Reflection axis" refers to the polarization direction in which reflectance is maximized in a plane when linearly polarized light is incident. "Transmission axis" refers to the direction perpendicular to the absorption axis or reflection axis in a plane. "Slow axis" refers to the direction in which refractive index is maximized in a plane.

[0014] In this specification, angles (such as "90°") and their relationships (such as "perpendicular" and "parallel") are understood to include the range of error permitted in the technical field to which the present invention pertains. For example, this means being within the range of ±10° of the exact angle, and the error from the exact angle is preferably 5° or less, and more preferably 3° or less.

[0015] 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) into AxoScan, the following 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).

[0016] 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).

[0017] 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 (the direction in which the in-plane refractive index is maximum) of the film is nx, the refractive index in the in-plane 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 value, and the negative A plates have a negative Rth value. Formula (A1) nx>ny≒nz Formula (A2) ny<nx≒nz Note that the above "≒" includes 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".

[0018] [Laminate] The laminate of the present invention is a laminate having a curved surface portion, and includes an optically absorptive anisotropic film and an optically reflective anisotropic film. The optically absorptive anisotropic film of the laminate of the present invention satisfies at least one of the following formulas (1) and (2), and the following formula (3).

[0019] The laminate of the present invention, i.e., a laminate having an optically absorptive anisotropic film and an optically reflective anisotropic film and having a curved surface portion, as described above, can suppress the occurrence of ghosts when used in a goggle-type display device because the optically absorptive anisotropic film satisfies at least one of the following formulas (1) and (2) and the following formula (3). The mechanism is unclear in detail, but is presumed to be roughly as follows. First, for a laminate having an optically absorptive anisotropic film and an optically reflective anisotropic film, the curved surface must be processed under high-temperature conditions (e.g., 170°C or higher) when forming the curved surface portion. It is believed that processing the curved surface under such high-temperature conditions causes the loss of the function of the optically absorptive anisotropic film (i.e., absorption anisotropy). Furthermore, even if the humidification treatment described in Patent Document 1 is performed, this function may not be fully restored depending on the humidification treatment conditions, or wrinkles may occur on the surface of the optically absorptive anisotropic film facing the optically reflective anisotropic film, which is thought to cause the ghost to be visible. Therefore, in the present invention, by using an optically absorptive anisotropic film that satisfies at least one of the formulas (1) and (2) described below and the formula (3) described below, it is possible to suppress the deterioration of the functionality of the optically absorptive anisotropic film during curved surface processing under high temperature conditions, and also to suppress the occurrence of wrinkles, thereby suppressing the occurrence of ghosts.

[0020] [Curved Surface Portion] As described above, the laminate of the present invention has a curved surface portion. Here, the term "curved surface portion" refers to a portion having a curved surface shape. The term "curved surface shape" refers to a shape having a curvature greater than zero, and includes a developable curved surface shape and a three-dimensional curved surface shape. The radius of curvature of a shape having a curvature is preferably 10 mm to 120 mm, more preferably 15 to 90 mm. A developable surface refers to a surface that can be developed into a plane without expanding or contracting each part of the surface. Examples of developable curved surfaces include surfaces corresponding to the circumferential surfaces of a cylinder, an elliptical cylinder, a cone, and an elliptical cone, and may be either a convex or concave curved surface. 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 a developable surface. Examples of three-dimensional curved surfaces include surfaces corresponding to a sphere and a spheroid, and surfaces corresponding to a curved surface whose cross section is a parabola or hyperbola (e.g., a paraboloid of revolution), and may be either a convex or concave curved surface.

[0021] In the present invention, the curved surface portion preferably has a curved surface that is not a developable surface, because this makes the effect of suppressing the occurrence of ghosts more apparent.

[0022] Furthermore, in the present invention, in order to make the effect of suppressing the occurrence of ghost images more apparent, it is preferable that the curvature of the curved surface with the smallest curvature in the curved surface portion (hereinafter also abbreviated as "minimum curvature curved surface") be 50 mm or less, more preferably 5 to 45 mm, and even more preferably 5 to 40 mm.

[0023] Furthermore, in the present invention, the curved surface shape of the curved surface portion is preferably a lens shape. Examples of the lens shape include a spherical shape and a spheroidal shape, and the shape may be a convex lens shape or a concave lens shape.

[0024] FIG. 1 shows an example of a laminate of the present invention. FIG. 1 is a top view of the laminate, and FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. As shown in FIGS. 1 and 2, the laminate 10 has a curved shape. More specifically, as shown in FIG. 2, the laminate 10, which includes an optically absorptive anisotropic film 12 and an optically reflective anisotropic film 14, has a shape (convex shape) that is curved convexly toward the upper side of the page. In other words, the laminate 10 has a convex shape that protrudes toward one surface. It can also be said that the laminate 10 has a concave shape that is recessed toward the other surface. While FIG. 1 shows an embodiment in which the shape of the laminate when viewed in plan is pentagonal, the present invention is not limited to this embodiment, and the shape of the laminate when viewed in plan may be rectangular, circular, or another shape.

[0025] [Light-absorption anisotropic film] The light-absorption anisotropic film included in the laminate of the present invention is a film having absorption anisotropy, and preferably has absorption anisotropy in the in-plane direction of the light-absorption anisotropic film. In particular, the light-absorption anisotropic film preferably functions as an absorptive linear polarizer. Furthermore, as described above, the light-absorption anisotropic film included in the laminate of the present invention is a light-absorption anisotropic film (hereinafter also referred to as "specific light-absorption anisotropic film") that satisfies at least one of the following formulas (1) and (2) and the following formula (3), and is preferably a specific light-absorption anisotropic film that satisfies all of the following formulas (1) to (3). Formula (1): Tm (peak top) ≧ 205°C Formula (2): ΔHm ≧ 100 mJ / mg Formula (3): Sa ≦ 20 nm In the above formulas (1) to (3), Tm (peak top) represents the peak top temperature of the endothermic peak in a differential scanning calorimetry (DSC) curve obtained when the temperature is raised from 25°C to 300°C at 10°C / min. ΔHm represents the heat of solution of the endothermic peak in a DSC curve obtained when the temperature is raised from 25°C to 300°C at 10°C / min. Sa represents the arithmetic mean height.

[0026] <Differential Scanning Calorimetry> As described above, Tm (peak top) and ΔHm are determined from the endothermic peak of the DSC curve obtained when the temperature is raised from 25° C. to 300° C. at a rate of 10° C. / min in a DSC. Here, the DSC curve is a curve showing the change in the amount of heat absorbed and heated by the film, with the horizontal axis representing temperature and the vertical axis representing heat flow, and is measured using a differential scanning calorimeter according to a method in accordance with JIS K7122:2012 (heat flux differential scanning calorimetry).

[0027] <Arithmetic Mean Height> The arithmetic mean height (Sa) can be calculated by measuring the surface shape in wave mode using a non-contact surface / layer cross-sectional shape measurement system, VertScan (registered trademark) 2.0 (Ryoka Systems).

[0028] In the present invention, the numerical ranges of the parameters represented by the above formulas (1) to (3) are preferably the numerical ranges represented by the following formulas (1-1) to (3-1), and more preferably the numerical ranges represented by the following formulas (1-2) to (3-2). Formula (1-1): Tm (peak top) ≧ 206°C Formula (2-1): ΔHm ≧ 105 mJ / mg Formula (3-1): Sa ≦ 17 nm Formula (1-2): Tm (peak top) ≧ 207°C Formula (2-2): ΔHm ≧ 110 mJ / mg Formula (3-2): Sa ≦ 15 nm

[0029] In the present invention, the thickness (average film thickness) of the specific optical absorption anisotropic film is not particularly limited, but from the viewpoint of thinning the device, it is preferably 8 μm or less, more preferably 0.3 to 7.0 μm, and even more preferably 0.5 to 6.0 μm.

[0030] The material of such a specific optically absorptive anisotropic film is not particularly limited as long as it satisfies at least one of the above formulas (1) and (2) and the above formula (3), but it is preferably a polarizer made of a resin film (e.g., a polyvinyl alcohol (PVA)-based resin film, etc.) containing a dichroic substance (e.g., iodine, a dichroic dye, etc., as a component of the optically absorptive anisotropic film-forming composition described later), and more preferably a polarizer made of a PVA-based resin film containing iodine. Note that, in the present invention, from the viewpoint of forming an optically absorptive anisotropic film that satisfies at least one of the above formulas (1) and (2) and the above formula (3), it is preferable to carry out a predetermined annealing process or humidification process after curved surface processing, as shown in the manufacturing method of the laminate of the present invention described later.

[0031] [Light-reflecting anisotropic film] The light-reflecting anisotropic film of the laminate of the present invention is a film having reflection anisotropy, and it is preferable that the light-reflecting anisotropic film has reflection anisotropy in the in-plane direction. In particular, it is preferable that the light-reflecting anisotropic film functions as a reflective polarizer. Examples of the reflective polarizer include a cholesteric liquid crystal layer and a linear polarization type reflective polarizer.

[0032] <Cholesteric Liquid Crystal Layer> A cholesteric liquid crystal layer is an optical component that separates incident light into right-handed circularly polarized light and left-handed circularly polarized light, specularly reflecting one circularly polarized light and transmitting the other circularly polarized light. Examples of cholesteric liquid crystal layers include cholesteric liquid crystal layers formed by fixing a cholesteric liquid crystal phase. Cholesteric liquid crystal layers are preferred as optical films used in curved surface molding because they suppress a decrease in the degree of polarization and distortion of the polarization axis when stretched or molded into a three-dimensional shape. Furthermore, they are less likely to experience a decrease in the degree of polarization due to distortion of the polarization axis.

[0033] The cholesteric liquid crystal layer preferably includes a blue light-reflecting layer having a reflectance of 40% or more at a wavelength of 460 nm, a green light-reflecting layer having a reflectance of 40% or more at a wavelength of 550 nm, a yellow light-reflecting layer having a reflectance of 40% or more at a wavelength of 600 nm, and a red light-reflecting layer having a reflectance of 40% or more at a wavelength of 650 nm. This configuration is preferable because it can exhibit high reflection characteristics over a wide wavelength range in the visible range. The reflectances mentioned above are those when unpolarized light is incident on the cholesteric liquid crystal layer at each wavelength. The cholesteric liquid crystal layer may also have a pitch gradient structure in which the helical pitch of the cholesteric liquid crystal phase is continuously varied in the thickness direction.

[0034] It is also preferable to use, as the cholesteric liquid crystal layer, a cholesteric liquid crystal layer formed by fixing a cholesteric liquid crystal phase containing a rod-shaped liquid crystal compound and a cholesteric liquid crystal layer formed by fixing a cholesteric liquid crystal phase containing a discotic liquid crystal compound in combination. In such a configuration, the cholesteric liquid crystal phase containing the rod-shaped liquid crystal compound has a positive Rth, while the cholesteric liquid crystal phase containing the discotic liquid crystal compound has a negative Rth, so that the Rths of the two phases are offset, thereby suppressing the occurrence of ghosts even when light is incident from an oblique direction, which is preferable.

[0035] The thickness of the cholesteric liquid crystal layer is not particularly limited, but is preferably 30 μm or less, more preferably 15 μm or less, from the viewpoint of thinning. There is no particular lower limit, and it is often 1 μm or more.

[0036] <Linearly Polarized Reflective Polarizer> A linearly polarized reflective polarizer is a polarizer that reflects one of mutually orthogonal linearly polarized light beams and transmits the other linearly polarized light beam. Examples of linearly polarized reflective polarizers include a film obtained by stretching a dielectric multilayer film and a wire grid polarizer. Commercially available products include a reflective polarizer (product name: APF) manufactured by 3M and a wire grid polarizer (product name: WGF) manufactured by Asahi Kasei Corporation.

[0037] [Retardation Layer] The laminate of the present invention preferably further comprises a retardation layer. Examples of the retardation layer include a retardation layer having a function of converting linearly polarized light into circularly polarized light, and a positive C plate.

[0038] <Retardation Layer Having the Function of Converting Linearly Polarized Light into Circularly Polarized Light> A retardation layer having the function of converting linearly polarized light into circularly polarized light (hereinafter also simply referred to as a "specific retardation layer") is a type of retardation layer. The specific retardation layer is not particularly limited as long as it has the function of converting linearly polarized light into circularly polarized light, and examples thereof include 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 of the λ / 4 plate at a wavelength of 550 nm is not particularly limited, but is preferably 120 to 150 nm, more preferably 125 to 145 nm, and even more preferably 135 to 140 nm. In addition to the λ / 4 plate, a retardation layer 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 is also preferred.

[0039] The specific retardation layer may have reverse wavelength dispersion.The term "reverse wavelength dispersion" means that the retardation value at the wavelength increases as the wavelength increases.The specific retardation layer may also have a multi-layer structure, and a specific embodiment of this case may be a broadband λ / 4 plate formed by laminating a λ / 4 plate and a λ / 2 plate.The angle between the slow axis of the specific retardation layer and the absorption axis of the light absorption anisotropic film is not particularly limited, but is preferably within 45°±10°.

[0040] The specific retardation layer may be the layer that is made by fixing the liquid crystal compound that is twisted and aligned with the thickness direction as the helical axis.For example, as disclosed in Japanese Patent No. 05753922 and Japanese Patent No. 05960743, the retardation layer that has the layer that is made by fixing the rod-shaped liquid crystal compound or discotic liquid crystal compound that is twisted and aligned with the thickness direction as the helical axis can be enumerated.

[0041] The thickness of the specific retardation layer is not particularly limited, but is preferably 0.1 to 8 μm, more preferably 0.3 to 5 μm.

[0042] <Positive C Plate> A positive C plate is a type of retardation layer. A positive C plate is a retardation layer having an in-plane retardation of substantially zero and a negative retardation in the thickness direction. The positive C plate functions as an optical compensation layer for increasing the degree of polarization of transmitted light with respect to obliquely incident light. The in-plane retardation of the positive C plate at a wavelength of 550 nm is preferably 10 nm or less. The retardation of the positive C plate in the thickness direction at a wavelength of 550 nm is preferably −600 to −40 nm.

[0043] The material for forming the positive C plate is not particularly limited, but it is preferably formed from a composition containing a liquid crystal compound. Such a positive C plate can typically be obtained by vertically aligning a rod-shaped polymerizable liquid crystal compound contained in a polymerizable liquid crystal composition and fixing the alignment state by polymerization. Alternatively, the positive C plate can be formed from a composition containing a side-chain polymer liquid crystal compound as the liquid crystal compound.

[0044] The thickness of the positive C plate is not particularly limited, but from the viewpoint of thinning, it is preferably 0.5 to 10 μm, and more preferably 0.5 to 5 μm.

[0045] FIG. 3 shows another example of a laminate of the present invention. The laminate 50A shown in FIG. 3 has, in this order, an optically absorptive anisotropic film 52, a retardation layer 54 having the function of converting linearly polarized light into circularly polarized light, a positive C plate 56, and a cholesteric liquid crystal layer 58. FIG. 4 shows another example of a laminate of the present invention. The laminate 50B shown in FIG. 4 has, in this order, an optically absorptive anisotropic film 52, a linear polarization type reflective polarizer 60, a retardation layer 54 having the function of converting linearly polarized light into circularly polarized light, and a positive C plate 56. As shown in FIGS. 3 and 4, all of the components included in the laminates 50A and 50B have the same curved surface shape as the optically absorptive anisotropic film 52. When the retardation layer 54 in the laminates 50A and 50B is a λ / 4 plate, the angle between the slow axis of the retardation layer 54 and the transmission axis of the optically absorptive anisotropic film 52 is preferably within the range of 45°±10°. The laminates 50A and 50B each include two retardation layers: a retardation layer 54 and a positive C plate 56. A retardation layer having the function of converting linearly polarized light into circularly polarized light may be disposed on the side of the optically absorptive anisotropic film 52 of the laminate 50A opposite the retardation layer 54. A retardation layer having the function of converting linearly polarized light into circularly polarized light may be disposed on the side of the optically absorptive anisotropic film 52 of the laminate 50B opposite the linear polarization type reflective polarizer 60. The laminates 50A and 50B are suitable for use in the goggle-type display device described below. The optically absorptive anisotropic film 52 is the optically absorptive anisotropic film described above. The optically absorptive anisotropic film 52 corresponds to the optically absorptive anisotropic film 12 shown in FIGS. 1 and 2.

[0046] [Resin Lens] The laminate of the present invention preferably further comprises a resin lens, because this effectively suppresses the generation of ghost images. The resin lens preferably has a curved surface and a maximum thickness of 3 mm or more. The curved surface of the resin lens has the same meaning as that described above for the laminate of the present invention. The maximum thickness of the resin lens is preferably 4 mm or more, more preferably 5 to 10 mm. Such a resin lens is not particularly limited, but may be, for example, a lens-shaped mold used to form the curved surface (e.g., the mold indicated by reference numeral 20 in FIG. 6 or the mold indicated by reference numeral 26 in FIG. 9). Examples of materials that can be used for such a resin lens include conventional plastic materials such as polyester resin, polycarbonate resin, polyamide resin, polyolefin resin, polyacetal resin, (thio)urethane resin, episulfide resin, acrylic resin, vinyl resin, vinylidene resin, epoxy resin, cellulose-based resin, and nylon resin.

[0047] [Surface Antireflection Layer] The laminate of the present invention may have a surface antireflection layer. In the laminate of the present invention, the surface antireflection layer is preferably disposed on the surface-most side. The surface antireflection layer may be disposed on only one surface side of the laminate, or on both surfaces. The type of surface antireflection layer is not particularly limited, but from the viewpoint of further reducing the reflectance, moth-eye films and AR (Anti-Reflection) films are preferred. Furthermore, moth-eye films are preferred because they can maintain high antireflection performance even when the film thickness varies due to stretching and molding. The angle between the transmission axis of the linear polarization type reflective polarizer and the transmission axis of the light absorption anisotropic film is preferably within the range of 0 to 10°.

[0048] [Adhesive Layer] The laminate of the present invention may or may not have a pressure-sensitive adhesive layer (i.e., a pressure-sensitive adhesive layer and / or an adhesive layer). When the laminate has a pressure-sensitive adhesive layer, the number of pressure-sensitive adhesive layers is preferably one or two. Examples of pressure-sensitive adhesives constituting the pressure-sensitive adhesive layer include pressure-sensitive adhesives and adhesives. 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, with acrylic-based pressure-sensitive adhesives (pressure-sensitive adhesives) being preferred. 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-curable adhesives, and visible light-curable adhesives, with ultraviolet-curable adhesives being preferred.

[0049] The thickness of the pressure-sensitive adhesive layer is not particularly limited, but from the viewpoint of thinning, it is preferably 25 μm or less, more preferably 15 μm or less, and even more preferably 5 μm or less. The lower limit is not particularly limited, and it is often 0.1 μm or more.

[0050] [Support] The laminate of the present invention may have a support. The support can be placed in any location. For example, when the cholesteric liquid crystal layer and the retardation layer are films to be transferred from a temporary support, the support can be used as the transfer destination. The type of support is not particularly limited, but a transparent support is preferred. Examples include films such as cellulose acylate, polycarbonate, polysulfone, polyethersulfone, polyacrylate, polymethacrylate, cyclic polyolefin, polyolefin, polyamide, polystyrene, and polyester. Among these, cellulose acylate film, cyclic polyolefin film, polyacrylate film, or polymethacrylate film is preferred as the support. Commercially available cellulose acetate films (e.g., "TD80U" and "Z-TAC" manufactured by Fujifilm Corporation) can also be used. Furthermore, it is preferable that the support have a small retardation. Specifically, the in-plane retardation at a wavelength of 550 nm is preferably 10 nm or less, and the absolute value of the retardation in the thickness direction at a wavelength of 550 nm is preferably 50 nm or less.

[0051] From the viewpoint of stretching and forming treatments, the support preferably has a tan δ peak temperature of 170° C. or less. From the viewpoint of enabling forming at low temperatures, the tan δ peak temperature is preferably 150° C. or less, more preferably 130° C. or less.

[0052] Here, the method for measuring tan δ will be described. Using a dynamic viscoelasticity measuring device (DVA-200 manufactured by IT Measurement Control Co., Ltd.), E" (loss modulus) and E' (storage modulus) are measured under the following conditions for a film sample that has been conditioned in advance in an atmosphere at a temperature of 25°C and a humidity of 60% Rh for at least 2 hours, and the value obtained from this is tan δ (= E" / E'). Device: DVA-200 manufactured by IT Measurement Control Co., Ltd. Sample: 5 mm, length 50 mm (gap 20 mm) Measurement conditions: tension mode Measurement temperature: -150 to 220°C Heating condition: 5°C / min Frequency: 1 Hz

[0053] The thickness of the support is not particularly limited, but is preferably from 5 to 300 μm, more preferably from 5 to 100 μm, and even more preferably from 5 to 70 μm.

[0054] The thickness of the laminate of the present invention is not particularly limited, but when the laminate does not include a pressure-sensitive adhesive layer or a support, the thickness of the laminate is preferably 100 μm or less, more preferably 90 μm or less. The lower limit is not particularly limited, but is often 10 μm or more. When the laminate of the present invention includes one of a pressure-sensitive adhesive layer and a support, but does not include the other, the value obtained by subtracting the thickness of one of the layers from the thickness of the laminate is preferably 100 μm or less, more preferably 90 μm or less. The lower limit is not particularly limited, but is often 10 μm or more. When the laminate of the present invention includes both a pressure-sensitive adhesive layer and a support, the value obtained by subtracting the thickness of the pressure-sensitive adhesive layer and the thickness of the support from the thickness of the laminate is preferably 100 μm or less, more preferably 90 μm or less. The lower limit is not particularly limited, but is often 10 μm or more.

[0055] [Method for Manufacturing Laminate] The method for manufacturing the laminate of the present invention (hereinafter also referred to as the "manufacturing method of the present invention") is not particularly limited, and examples thereof include a manufacturing method having a curved surface processing step in which a planar laminate having the above-mentioned light absorption anisotropic film and light reflection anisotropic film is subjected to curved surface processing at 170°C or higher to form a curved surface portion, and preferred examples of the manufacturing method include a slow cooling step in which the planar laminate is cooled at a cooling rate of 3°C / min or less after the curved surface processing step, and / or a humidification treatment step in which the planar laminate is subjected to humidification treatment for 30 minutes or less in an environment at a temperature of 40 to 65°C and a relative humidity of 85 to 95%. Here, the method for manufacturing the planar laminate is not particularly limited, and examples thereof include a method in which the above-mentioned light absorption anisotropic film (e.g., a polarizer composed of a PVA-based resin film containing iodine) and the above-mentioned light reflection anisotropic film (e.g., a linear polarization type reflective polarizer) are bonded together using an adhesive.

[0056] [Curved Surface Processing Step] The curved surface processing step is a step of forming a curved surface portion by subjecting a planar laminate to curved surface processing at 170° C. or higher. Examples of such curved surface processing include a method using a mold having a convex molding surface or a mold having a concave molding surface.

[0057] First, the phenomenon that occurs when a film is molded using a mold having a concave molding surface will be described with reference to Figures 5 to 7. Figures 5 and 6 show the procedure for molding a film using a mold having a concave molding surface, and Figure 7 shows a film 22 (i.e., a planar laminate) used for molding. As shown in Figure 5, film 22 is placed on mold 20 having a concave molding surface, and as shown in Figure 6, film 22 is deformed so as to conform to the molding surface of mold 20, thereby obtaining a film 24 to which the concave shape has been transferred (i.e., a laminate having a curved surface).

[0058] Next, the phenomenon that occurs when a film is molded using a mold having a convex molding surface will be described with reference to Figures 7 to 9. Figures 8 and 9 show the procedure for molding a film using a mold having a convex molding surface, and Figure 7 shows a film 22 (i.e., a planar laminate) used for molding. As shown in Figure 8, film 22 is placed on mold 26 having a convex molding surface, and as shown in Figure 9, film 22 is deformed so as to conform to the molding surface of mold 26, thereby obtaining a film 28 to which the convex shape has been transferred (i.e., a laminate having a curved surface).

[0059] [Slow Cooling Step] The slow cooling step is a step of cooling at a cooling rate of 3°C / min or less after the curved surface processing step. In the manufacturing method of the present invention, the slow cooling step is included, so that the optically absorptive anisotropic film in the laminate to be produced is more likely to satisfy at least one of the above formulas (1) and (2), and the above formula (3).

[0060] The cooling rate in the slow cooling step is preferably 2° C. / min or less, more preferably 1° C. / min or less. There is no particular lower limit to the cooling rate in the slow cooling step, but it is preferably 0.1° C. / min or more.

[0061] [Moisturizing Treatment Step] The moisturizing treatment step is a step of performing moisturizing treatment for 30 minutes or less in an environment at a temperature of 40 to 65°C and a relative humidity of 85 to 95% after the curved surface processing step. By including the moisturizing treatment step in the production method of the present invention, the optically absorptive anisotropic film in the laminate to be produced is more likely to satisfy at least one of the formulas (1) and (2) and the formula (3).

[0062] The temperature in the humidification treatment step is preferably 50 to 65° C., more preferably 55 to 65° C., and even more preferably 60 to 65° C. The relative humidity in the humidification treatment step is preferably more than 85% and less than 95%, and more preferably 87 to 93%.

[0063] [Composite Lens] The composite lens of the present invention comprises the above-described laminate of the present invention, a lens, and a half mirror, in this order. FIG. 10 shows an example of the composite lens of the present invention. A composite lens 70 comprises a laminate 72, a lens 74, and a half mirror 76, in this order. As shown in FIG. 10, all of the components included in the composite lens 70 have the same curved surface shape as the laminate 72. The configuration of the laminate 72 is as described above. Below, the components other than the laminate included in the composite lens will be described in detail.

[0064] [Lens] A compound lens has a lens. Examples of lenses include convex lenses and concave lenses. Examples of convex lenses include biconvex lenses, plano-convex lenses, and convex meniscus lenses. Examples of concave lenses include biconcave lenses, plano-concave lenses, and concave meniscus lenses. As lenses used in virtual reality display devices, convex meniscus lenses or concave meniscus lenses are preferred in terms of expanding the viewing angle, and concave meniscus lenses are more preferred in terms of minimizing chromatic aberration. Lens materials that are transparent to visible light, such as glass, crystal, and plastic, can be used. Since birefringence in lenses can cause rainbow unevenness and light leakage, the smaller the birefringence, the more preferable, and materials with zero birefringence are more preferred.

[0065] [Half Mirror] The composite lens of the present invention has a half mirror. The half mirror is a conventionally known half mirror that transmits approximately half of incident light and reflects the remaining approximately half. The transmittance of the half mirror is preferably 50±30%, more preferably 50±10%. The type of half mirror is not particularly limited, but examples include a reflective layer made of a metal. Examples of metals include silver and aluminum. The thickness of the reflective layer is preferably 1 to 20 nm, more preferably 2 to 10 nm, and even more preferably 3 to 6 nm.

[0066] [Goggle-type display device] The goggle-type display device of the present invention has the laminate or composite lens of the present invention described above. Examples of goggle-type display devices include head-mounted displays, and more specifically, virtual reality display devices. FIG. 11 is a schematic diagram showing an example of the configuration of a goggle-type display device. The goggle-type display device 80 shown in FIG. 11 has, from the right side in the figure, an image display panel 82, a circular polarizer 84, a half mirror 86, a lens 88, and a laminate 90 of the present invention. Note that the laminate 90 used in FIG. 11 has a configuration similar to the laminate 50A described above, with the light absorption anisotropic film 52 disposed on the eye side. The laminate 90, lens 88, and half mirror 86 shown in FIG. 11 constitute the composite lens described above. In the goggle-type display device 80 shown in FIG. 11, light ray 92 emitted from the image display panel 82 passes through the circular polarizer 84 to become circularly polarized light, and then passes through the half mirror 86. The light ray 92 then passes through the lens 88, enters the reflective polarizer layer (e.g., a cholesteric liquid crystal layer) included in the laminate 90 of the present invention, is reflected, passes through the lens 88 again, is reflected again by the half mirror 86, passes through the lens 88 again, and enters the laminate 90. At this time, the circular polarization state of the light ray 92 does not change when reflected by the laminate 90, but when reflected by the half mirror 86, it changes to circular polarization with a direction of rotation opposite to that of the circular polarization when it entered the laminate 90. Therefore, the light ray 92 passes through the laminate 90 and is visually recognized by the user. Furthermore, when the light ray 92 is reflected by the half mirror 86, the image is magnified because the half mirror is shaped like a concave mirror, allowing the user to view the magnified virtual image. The above-mentioned mechanism is called a round-trip optical system or a folded optical system.

[0067] The image display panel 82 is a known image display panel (display panel) such as an organic electroluminescence display panel. In the illustrated example, the image display panel 82 emits an unpolarized image (image light). The unpolarized image emitted by the image display panel 82 passes through the circular polarizer 84 and is converted into circularly polarized light.

[0068] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, 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.

[0069] Example 1 Preparation of Absorption-Type Anisotropic Film A1 Having an Optically Absorbent Anisotropic Layer One side of a polyethylene terephthalate (100 μm) resin substrate was subjected to corona treatment. Next, 100 parts by mass of a PVA-based resin prepared by mixing polyvinyl alcohol (polymerization degree 4200, saponification degree 99.2 mol%) and acetoacetyl-modified PVA (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "GOHSEFIRM") in a 9:1 ratio was mixed with 13 parts by mass of potassium iodide, and the mixture was dissolved in water to prepare an aqueous PVA solution (coating solution). The PVA aqueous solution was applied to the corona-treated surface of the resin substrate and dried to obtain a laminate. The resulting laminate was uniaxially stretched 2.4 times in the longitudinal direction of the resin substrate at 130°C. After stretching, the laminate was immersed in an insolubilizing bath (a boric acid aqueous solution prepared by blending 4 parts by mass of boric acid with 100 parts by mass of water) at a liquid temperature of 40°C for 30 seconds. The laminate was then immersed in a boric acid aqueous solution (boric acid concentration 4% by mass, potassium iodide concentration 5% by mass) at a liquid temperature of 70°C, and uniaxially stretched in the machine direction (longitudinal direction) to a total stretch ratio of 5.5 times. The laminate was then immersed in a cleaning bath (an aqueous solution obtained by blending 3 parts by mass of potassium iodide with 100 parts by mass of water) at a liquid temperature of 20°C. The laminate was then dried in an oven maintained at approximately 90°C, and brought into contact with a stainless steel heating roll maintained at a surface temperature of approximately 75°C. In this way, a light-absorption anisotropic film P1 (polarizer P1) was formed on the resin substrate, and an absorptive anisotropic film A1 having a resin substrate / polarizer P1 configuration was obtained. The thickness of the polarizer P1 in the absorptive anisotropic film A1 was 5 μm.

[0070] [Preparation of Retardation Film 1 Having Positive A Plate] <Preparation of Support> The following composition was charged into a mixing tank, stirred, and further heated at 90°C for 10 minutes. The obtained composition was then filtered through filter paper with an average pore size of 34 μm and a sintered metal filter with an average pore size of 10 μm to prepare a dope. The solid content concentration of the dope was 23.5 mass%, the amount of plasticizer added was the ratio relative to cellulose acylate, and the solvent for the dope was methylene chloride / methanol / butanol = 81 / 18 / 1 (mass ratio).

[0071] ------------------------------------------------ Cellulose acylate dope ---------------------------------------------------------------- Cellulose acylate (acetyl substitution degree 2.86, viscosity average degree of polymerization 310) 100 parts by mass Sugar ester compound 1 (formula (S4) below) 6.0 parts by mass Sugar ester compound 2 (formula (S5) below) 2.0 parts by mass Silica particle dispersion (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 0.1 part by mass Solvent (methylene chloride / methanol / butanol) 351.9 parts by mass

[0072]

[0073]

[0074] The dope prepared above was cast using a drum film-forming machine. The dope was cast from a die onto a metal support cooled to 0°C, and the resulting web (film) was then peeled off from the drum. The drum was made of SUS (stainless steel).

[0075] The web (film) obtained by casting was peeled from the drum and then dried for 20 minutes in a tenter apparatus, in which both ends of the web were clipped with clips while the film was being transported at 30 to 40°C. Subsequently, the web was post-dried by zone heating while being transported with a roll. The obtained web was knurled and then wound up to give cellulose acylate film A1. The obtained cellulose acylate film A1 had a thickness of 60 μm, an in-plane retardation Re(550) of 1 nm at a wavelength of 550 nm, and a thickness direction retardation Rth(550) of 35 nm at a wavelength of 550 nm.

[0076] <Formation of Photo-Alignment Film> A coating solution E1 for forming a photo-alignment film having the following composition was continuously coated on the above-mentioned cellulose acylate film A1 using a wire bar. The cellulose acylate film A1 on which the coating film was formed was dried with hot air at 140°C for 120 seconds, and then the coating film was irradiated with polarized ultraviolet light (10 mJ / cm ２ , using an ultra-high pressure mercury lamp) to form a photo-alignment film E1 with a thickness of 0.2 μm, thereby obtaining a TAC film with a photo-alignment film.

[0077] -------------------------------------------------- Coating liquid E1 for forming photoalignment film -------------------------------------------------- - 100.00 parts by mass of the polymer PA-2 shown below - 5.00 parts by mass of the thermal cationic polymerization initiator PAG-1 shown above - 0.005 parts by mass of the acid generator CPI-110TF shown below - 16.50 parts by mass of isopropyl alcohol - 1072.00 parts by mass of butyl acetate - 268.00 parts by mass of methyl ethyl ketone --------------------------------------------------

[0078] Polymer PA-2 (In the formula below, the numerical value for each repeating unit represents the content (% by mass) of each repeating unit relative to all repeating units; weight average molecular weight: 45,000)

[0079] Acid generator CPI-110TF

[0080] Composition F1 having the following composition was applied onto the photo-alignment film E1 using a bar coater. The coating film formed on the photo-alignment film E1 was heated to 120°C with hot air, then cooled to 60°C, and then irradiated with 100 mJ / cm2 at a wavelength of 365 nm using a high-pressure mercury lamp under a nitrogen atmosphere. ２ The coating film was irradiated with ultraviolet light of 500 mJ / cm 2 while being heated to 120°C. ２ The coating film was irradiated with ultraviolet light of 1000 nm, thereby fixing the alignment of the liquid crystal compound, and a retardation layer film 1 having a positive A plate F1 was produced. The thickness of the positive A plate F1 was 2.5 μm, and Re(550) was 144 nm. The positive A plate also satisfied the relationship Re(450)≦Re(550)≦Re(650). Re(450) / Re(550) was 0.82. The positive A plate corresponds to a so-called λ / 4 plate.

[0081] - 43.50 parts by mass of polymerizable liquid crystal compound LA-1 described below - 43.50 parts by mass of polymerizable liquid crystal compound LA-2 described below - 8.00 parts by mass of polymerizable liquid crystal compound LA-3 described below - 5.00 parts by mass of polymerizable liquid crystal compound LA-4 described below - 0.55 parts by mass of polymerization initiator PI-1 described below - 0.20 parts by mass of leveling agent T-1 described below - 235.00 parts by mass of cyclopentanone

[0082] Polymerizable liquid crystal compound LA-1 (tBu represents a tertiary butyl group)

[0083] Polymerizable liquid crystal compound LA-2

[0084] Polymerizable liquid crystal compound LA-3

[0085] Polymerizable liquid crystal compound LA-4 (Me represents a methyl group)

[0086] Polymerization initiator PI-1

[0087] Leveling agent T-1 (in the formula below, the numerical value for each repeating unit represents the content (% by mass) of each repeating unit relative to all repeating units; weight average molecular weight: 25,000)

[0088] [Preparation of Retardation Film 2 Having a Positive C Plate] The above-described cellulose acylate film A1 was used as a temporary support. The cellulose acylate film A1 was passed through a dielectric heating roll at a temperature of 60°C to raise the surface temperature of the film to 40°C, and then an alkaline solution having the composition shown below was applied to one side of the film using a bar coater in an amount of 14 ml / m. ２ The film was heated to 110°C and transported for 10 seconds under a steam-type far-infrared heater manufactured by Noritake Co., Ltd. Next, pure water was applied to the film at a rate of 3 ml / m using the same bar coater. ２ Next, after repeating washing with water using a fountain coater and draining with an air knife three times, the film was transported to a drying zone at 70° C. for 10 seconds and dried to prepare an alkali-saponified cellulose acylate film A1.

[0089] ---------------------------------------------------------------- (Alkaline solution) ---------------------------------------------------------------- Potassium hydroxide 4.7 parts by mass, water 15.8 parts by mass, isopropanol 63.7 parts by mass, fluorine-containing surfactant SF-1 (C １４ H ２９ O (CH ２ CH ２ O) ２０H) 1.0 part by mass; Propylene glycol 14.8 parts by mass

[0090] An alignment film-forming coating solution G1 having the following composition was continuously applied onto the above-mentioned alkali-saponified cellulose acylate film A1 using a #8 wire bar, and the resulting film was dried with hot air at 60°C for 60 seconds and then with hot air at 100°C for 120 seconds to form an alignment film G1.

[0091] ------------------------------------------------------------------ Coating liquid G1 for forming alignment film ------------------------------------------------------------------ Polyvinyl alcohol (PVA103, manufactured by Kuraray) 2.4 parts by mass Isopropyl alcohol 1.6 parts by mass Methanol 36 parts by mass Water 60 parts by mass ------------------------------------------------------------------

[0092] A coating solution H1 for forming a positive C plate having the following composition was applied onto the alignment film G1, and the resulting coating film was aged at 60° C. for 60 seconds, and then irradiated with 70 mW / cm 2 ２ An air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) was used, and the light output was 1000 mJ / cm ２ The liquid crystal compound was vertically aligned by irradiating the film with ultraviolet light of 1000 W at 1000 W to fix the alignment state, thereby producing a retardation layer film 2 having a positive C plate H1 with a thickness of 0.5 μm. The Rth(550) of the obtained positive C plate was −60 nm.

[0093] Coating liquid H1 for forming a positive C-plate -------------------------------- 80 parts by mass of the following liquid crystal compound LC-1 20 parts by mass of the following liquid crystal compound LC-2 1 part by mass of the following vertical alignment liquid crystal compound promoter S01 8 parts by mass of ethylene oxide-modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Industry Co., Ltd.) 3 parts by mass of Irgacure 907 (manufactured by BASF) 1 part by mass of Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 0.4 parts by mass of the following compound B03 170 parts by mass of methyl ethyl ketone 30 parts by mass of cyclohexanone --------------------------------

[0094] Liquid crystal compound LC-1

[0095] Liquid crystal compound LC-2

[0096] Vertical alignment liquid crystal compound promoter S01

[0097] Compound B03 (In the formula below, the numerical value for each repeating unit represents the content (% by mass) of each repeating unit relative to all repeating units; weight average molecular weight: 15,000)

[0098] [Preparation of Laminated Film B1] The laminated film B1 was prepared according to the following procedure. A broadband dielectric multilayer film (3M trademark APF) was used as a light-reflection anisotropic film (linear polarization type reflective polarizer). Next, the positive A plate side of the retardation film 1 prepared above was attached to one surface of the APF, and the alignment film and support were peeled off. Furthermore, the positive C plate side of the retardation film 2 prepared above was attached to the liquid crystal surface exposed by peeling off the alignment film with an adhesive, and the support and alignment film were peeled off. Furthermore, the resin substrate side of the absorptive anisotropic film A1 was laminated to the other surface of the APF with an adhesive. This resulted in the preparation of a laminated film B1 consisting of polarizer P1 / resin substrate / adhesive layer / reflective polarizer (APF) / adhesive layer / positive A plate / positive C plate. The elastic modulus of the APF was 4277 MPa.

[0099] [Fabrication of Laminate C1] The laminate C1 was fabricated according to the following procedure. First, the laminate film B1 was heated to 180°C (infrared heating). Next, as shown in FIG. 12A , the heated laminate film B1 was placed at a predetermined position between the first mold 501 and the second mold 502. At this time, the polarizer P1 of the laminate film B1 was positioned facing the first mold 501. Next, a molding material 506 molten at 180°C was injected toward the laminate film B1 through the gate 505 of the first mold 501 and into a cavity formed by clamping the first mold 501 and the second mold 502. As a result, the molding material 506 molten at 180°C shaped the laminate film B1 onto the cavity surface, and simultaneously filled the cavity (see FIG. 12B ) (curved surface processing step). Furthermore, after the filling of the molding material 506 melted at 180°C was completed, the molten molding material 506 was cooled to room temperature and solidified to form a resin lens. The cooling rate was 3.0°C / min (slow cooling step). Next, the second mold 502 was moved to separate the first mold 501 and the second mold 502 (see FIG. 12C ). This resulted in a laminate C1 having a curved surface portion including a curved surface (minimum curvature: 50 mm) that was not a developed surface, in which the laminate film B1 was formed on the surface of the molding material 506.

[0100] [Formation of Half-Mirror Lens] A half-mirror lens consisting of a lens and a half-mirror was formed by depositing aluminum on the convex side of a lens [a convex meniscus lens LE1076-A (diameter 2 inches) manufactured by Thorlab] so that the reflectance was 40%.

[0101] [Preparation of Compound Lens] The laminate C1 was attached to the concave surface side of the half mirror lens prepared above using an adhesive to obtain a compound lens.

[0102] Example 2 A complex lens was produced in the same manner as in Example 1, except that a laminate (laminate C2) produced at a cooling rate of 1.2° C. / min in the slow cooling step was used.

[0103] Example 3 A complex lens was produced in the same manner as in Example 1, except that a laminate (laminate C3) produced at a cooling rate of 0.2° C. / min in the slow cooling step was used.

[0104] Example 4 A composite lens was produced in the same manner as in Example 1, except that a laminate (laminate C4) was used, which was produced by subjecting a laminate produced at a cooling rate of 30°C / min in the slow cooling step to a humidification treatment at 65°C and a relative humidity of 90% for 30 minutes.

[0105] Example 5 A complex lens was produced in the same manner as in Example 4, except that a laminate (laminate C5) produced at a cooling rate of 1.2° C. / min in the slow cooling step was used.

[0106] Example 6 A composite lens was produced in the same manner as in Example 5, except that the shapes of the cavities of the first mold 501 and the second mold 502 in the curved surface processing step were changed and a laminate having a curved surface portion including a curved surface that was not a developed surface (curvature of the minimum curvature curved surface: 80 mm) was used.

[0107] Comparative Example 1 A complex lens was produced in the same manner as in Example 1, except that a laminate (laminate H1) produced at a cooling rate of 30° C. / min in the slow cooling step was used.

[0108] Comparative Example 2 A complex lens was produced in the same manner as in Example 4, except that a laminate (laminate H2) produced by changing the humidification treatment time to 120 minutes was used.

[0109] Comparative Example 3 A complex lens was produced in the same manner as in Example 5, except that a laminate (laminate H3) produced by changing the humidification treatment time to 120 minutes was used.

[0110] [Evaluation] (1) Tm (peak top) and ΔHm For the optically absorption anisotropic films of the laminates C1 to C5 and H1 to H3 produced in Examples 1 to 6 and Comparative Examples 1 to 3, the melting point Tm and the heat of fusion ΔHm were measured from the DSC curves obtained by raising the temperature from 25° C. to 300° C. at a rate of 10° C. / min using an X-DSC7000 manufactured by Hitachi High-Tech Science. The results are shown in Table 1 below.

[0111] (2) Arithmetic Mean Height: The laminates C1 to C5 and H1 to H3 produced in Examples 1 to 6 and Comparative Examples 1 to 3 were peeled from the molding material 506 to form samples (surface roughness measurement samples), and the central portions of the samples were cut into 2 cm squares. These samples were attached to glass with an adhesive so that the polarizer faced the air side, and the arithmetic mean height Sa was measured using a non-contact surface / layer cross-sectional shape measurement system, VertScan (manufactured by Ryoka Systems Co., Ltd.). The results are shown in Table 1 below.

[0112] (3) A virtual reality display device "Huawei VR Glass" manufactured by Huawei, which is a virtual reality display device employing a ghost reciprocating optical system, was disassembled, and all of the compound lenses were removed. The compound lenses produced in Examples 1 to 6 and Comparative Examples 1 to 3 were incorporated into the main body in place of the removed compound lenses, and the compound lenses were further positioned so that the light-absorbing anisotropic film side was facing the eye, thereby producing a virtual reality display device. A black and white checkered pattern was displayed on the image display panel of the produced virtual reality display device, and the ghost visibility was visually evaluated according to the following evaluation criteria. The results are shown in Table 1 below. <Evaluation Criteria> A: Very slightly visible, but not noticeable. B: Slightly visible, but not noticeable. C: Strong ghosts were visible.

[0113]

[0114] As shown in Table 1, when a laminate having an optically absorptive anisotropic film that does not satisfy the above-mentioned formula (1) or (2) or an optically absorptive anisotropic film that does not satisfy the above-mentioned formula (3) was used in a goggle-type display device, it was found that the occurrence of ghosting could not be suppressed (Comparative Examples 1 to 3). In contrast, when a laminate having an optically absorptive anisotropic film that satisfies at least one of the above-mentioned formulas (1) and (2) and the above-mentioned formula (3) was used in a goggle-type display device, it was found that the occurrence of ghosting could be suppressed (Examples 1 to 6). Furthermore, from the manufacturing procedures of Examples 1 to 6 and Comparative Examples 1 to 3, it was found that when a predetermined slow cooling process or humidification process was performed after curved surface processing, the optically absorptive anisotropic film contained in the laminate satisfied at least one of the above-mentioned formulas (1) and (2) and the above-mentioned formula (3). Furthermore, a comparison between Example 5 and Example 6 revealed that the occurrence of ghosting could be further suppressed when the curvature of the minimum curvature curved surface was 50 mm or less.

[0115] REFERENCE SIGNS LIST 1 Maximum projected image 2 Circle X 3 Circle Y 4 Center of gravity 10 Laminate 12 Light-absorbing anisotropic film 14 Light-reflecting anisotropic film Z Any four points on the circle Y 20 Mold having a concave molding surface 22 Film 24 Film to which a concave shape has been transferred 26 Mold having a convex molding surface 28 Film to which a convex shape has been transferred 50A, 50B Laminate 54 Retardation layer having the function of converting linearly polarized light into circularly polarized light 56 ​​Positive C plate 58 Cholesteric liquid crystal layer 60 Linearly polarized reflective polarizer 70 Compound lens 72, 90 Laminate 74, 88 Lens 76, 86 Half mirror 80 Goggle-type display device 82 Image display device 84 Circular polarizer 92 Light ray 501 First mold 502 Second mold 506 Molding material

Claims

1. A laminate having a curved surface, the laminate comprising an optically absorptive anisotropic film and an optically reflective anisotropic film, wherein the optically absorptive anisotropic film satisfies at least one of the following formulas (1) and (2), and the following formula (3): Formula (1): Tm (peak top) ≧ 205°C Formula (2): ΔHm ≧ 100 mJ / mg Formula (3): Sa ≦ 20 nm In the formulas (1) to (3), Tm (peak top) represents the peak-top temperature of the endothermic peak in the DSC curve obtained by differential scanning calorimetry when the temperature is raised from 25°C to 300°C at 10°C / min. ΔHm represents the heat of solution of the endothermic peak in the DSC curve obtained by differential scanning calorimetry when the temperature is raised from 25°C to 300°C at 10°C / min. Sa represents the arithmetic mean height.

2. The laminate according to claim 1, wherein the curved portion has a curved surface that is not developable.

3. The laminate according to claim 1, wherein the smallest curvature of the curved surface in the curved surface portion is 50 mm or less.

4. The laminate according to claim 1, wherein the light-reflecting anisotropic film is a linear polarization type reflective polarizer that reflects one of mutually orthogonal linearly polarized light beams and transmits the other linearly polarized light beam.

5. The laminate according to claim 1, further comprising a resin lens, said resin lens having a curved surface and a maximum thickness of 3 mm or more.

6. The laminate according to claim 1, wherein the optically absorptive anisotropic film is a polyvinyl alcohol-based resin film containing iodine.

7. The laminate according to claim 1, wherein the optically absorptive anisotropic film has a thickness of 8 μm or less.

8. The laminate according to claim 1, further comprising a retardation layer.

9. A compound lens comprising, in this order, the laminate according to any one of claims 1 to 8, a lens, and a half mirror.

10. A goggle-type display device comprising the laminate according to any one of claims 1 to 8.

11. A method for producing a laminate according to any one of claims 1 to 8, comprising a curved surface processing step of forming a curved surface portion by performing curved surface processing at 170°C or higher.

12. The method for producing a laminate according to claim 11, further comprising a slow cooling step of cooling at a cooling rate of 3°C / min or less after the curved surface processing step.

13. The method for producing a laminate according to claim 11, further comprising a humidification treatment step of carrying out humidification treatment for 30 minutes or less in an environment at a temperature of 40 to 65°C and a relative humidity of 85 to 95% after the curved surface processing step.

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