Method for manufacturing optical laminate

Abstract

To provide an optical laminate with high quality at a high yield.SOLUTION: A manufacturing method of an optical laminate includes: preparing a first laminate 100 having a base material 53, an absorption type polarization film 28 formed on the base material 53, and a protective film 54 bonded to the absorption type polarization film 28; cutting the first laminate 100 into a prescribed shape to obtain a leaf-like first laminate 100; preparing a leaf-like second laminate 200 having a retardation member 30 having a first principal surface 30a and a second principal surface 30b facing each other and a first adhesive layer 41 arranged on the retardation member 30 side of the first principal surface 30a; and peeling the protective film 54 from the leaf-like first laminate 100 and bonding the absorption type polarization film 28 of the leaf-like first laminate 100 to the first adhesive layer 41 of the leaf-like second laminate 200. The absorption type polarization film 28 has a thickness of 7 μm or less and the protective film 54 has a tensile elastic modulus smaller than that of the base material 53.SELECTED DRAWING: Figure 1C

Description

[Technical Field]

[0001] The present invention relates to a method for producing an optical laminate. [Background technology]

[0002] Image display devices, such as liquid crystal display devices and electroluminescence (EL) display devices (e.g., organic EL display devices), are rapidly becoming popular. In image display devices, optical components such as retardation components and polarizing components are generally used to realize image display and improve image display performance (see, for example, Patent Document 1). These optical components can be integrated in advance and mounted on the image display device as an optical laminate.

[0003] In recent years, new applications for image display devices have been developed. For example, goggles with displays (VR goggles) for realizing virtual reality (VR) have begun to be commercialized. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-103286 Summary of the Invention [Problem to be solved by the invention]

[0005] As the applications of image display devices expand, there are cases where higher quality than before is required for the optical laminate including the optical member. For example, there are cases where it is desired that the optical axes of the optical members included in the optical laminate are aligned with high precision.

[0006] In view of the above, a main object is to provide a high-quality optical laminate with a good yield. [Means for solving the problem]

[0007] 1. A method for producing an optical laminate according to an embodiment of the present invention includes: preparing a first laminate having a substrate, an absorptive polarizing film formed on the substrate, and a protective film bonded to the absorptive polarizing film; cutting the first laminate into a predetermined shape to obtain a sheet of the first laminate; preparing a sheet of a second laminate having a retardation member having a first main surface and a second main surface facing each other, and a first pressure-sensitive adhesive layer disposed on the first main surface side of the retardation member; and peeling the protective film from the sheet of the first laminate and bonding the absorptive polarizing film of the first laminate to the first pressure-sensitive adhesive layer of the sheet of the second laminate, wherein the thickness of the absorptive polarizing film is 7 μm or less, and the tensile modulus of elasticity of the protective film is smaller than the tensile modulus of elasticity of the substrate. 2. In the manufacturing method described in 1 above, the tensile modulus of the protective film is 1.0 × 10 9 It may be less than Pa. 3. In the manufacturing method according to the above 1 or 2, the peeling force of the protective film from the absorptive polarizing film may be less than 0.01 N / 50 mm. 4. In the manufacturing method according to any one of the above items 1 to 3, the protective film may be a self-adhesive film. 5. In the manufacturing method according to any one of the above items 1 to 4, the haze of the protective film may be 3% or more. 6. The manufacturing method according to any one of 1 to 5 above may include bonding the absorptive polarizing film to the first pressure-sensitive adhesive layer, and then peeling the substrate from the absorptive polarizing film. 7. In the manufacturing method according to any one of 1 to 6 above, the sheet-like second laminate may have the same shape in a plan view as the first laminate after cutting. 8. In the manufacturing method according to any one of the above items 1 to 7, the second laminate may have a second pressure-sensitive adhesive layer disposed on the second main surface side of the retardation member. 9. In the manufacturing method described in 8 above, the second pressure-sensitive adhesive layer may have a thickness greater than that of the first pressure-sensitive adhesive layer. [Effects of the Invention]

[0008] According to the embodiments of the present invention, high-quality optical laminates can be provided with a high yield. [Brief explanation of the drawings]

[0009] [Figure 1A] 1A to 1C are diagrams illustrating an example of a manufacturing process for an optical laminate according to one embodiment of the present invention. [Figure 1B] This is a continuation of Figure 1A. [Figure 1C] This is a continuation of Figure 1B. [Figure 2] FIG. 1 is a schematic diagram showing a general configuration of an example of a display system for VR goggles. [Figure 3] FIG. 2 is a schematic cross-sectional view showing an example of details of an optical laminate. [Figure 4] FIG. 1 is a schematic perspective view showing an example of a multilayer structure included in a reflective polarizing film. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In order to clarify the description, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the embodiments, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in the drawings, the same or equivalent elements are given the same reference numerals, and redundant explanations may be omitted.

[0011] (Definition of terms and symbols) The definitions of terms and symbols used in this specification are as follows. (1) Refractive index (nx, ny, nz) "nx" is the refractive index in the direction in which the in-plane refractive index is greatest (i.e., the slow axis direction), "ny" is the refractive index in the direction perpendicular to the slow axis in the plane (i.e., the fast axis direction), and "nz" is the refractive index in the thickness direction. (2) In-plane phase difference (Re) "Re(λ)" is the in-plane retardation measured with light of wavelength λ nm at 23°C. For example, "Re(550)" is the in-plane retardation measured with light of wavelength 550 nm at 23°C. Re(λ) is calculated by the formula: Re(λ)=(nx-ny)×d, where d (nm) is the thickness of the layer (film). (3) Retardation in the thickness direction (Rth) "Rth(λ)" is the retardation in the thickness direction measured with light of wavelength λ nm at 23°C. For example, "Rth(550)" is the retardation in the thickness direction measured with light of wavelength 550 nm at 23°C. Rth(λ) is calculated by the formula: Rth(λ) = (nx - nz) × d, where d (nm) is the thickness of the layer (film). (4) Nz coefficient The Nz coefficient is calculated by Nz=Rth / Re. (5)Angle When angles are referred to herein, the angles include both clockwise and counterclockwise angles relative to a reference direction, so for example, "45°" means ±45°.

[0012] A method for producing an optical laminate according to an embodiment of the present invention includes preparing a first laminate having a substrate, an absorptive polarizing film, and a protective film; cutting the first laminate into a predetermined shape to obtain a sheet of the first laminate; preparing a sheet of a second laminate having a retardation member and a first adhesive layer; and peeling the protective film from the sheet of the first laminate and bonding the absorptive polarizing film of the first laminate to the first adhesive layer of the sheet of the second laminate.

[0013] 1A to 1C are diagrams showing an example of a manufacturing process for an optical laminate according to one embodiment of the present invention.

[0014] 1A shows a state in which a protective film 54 is attached to an absorptive polarizing film 28 formed on a substrate 53 to form a completed first laminate 100. The first laminate 100 is typically long and can be wound into a roll. Here, "long" refers to an elongated shape in which the length is sufficiently longer than the width, for example, a elongated shape in which the length is 10 times or more, preferably 20 times or more, the width.

[0015] The absorptive polarizing film 28 is typically composed of a film containing a dichroic substance such as iodine or an organic dye. The thickness of the absorptive polarizing film 28 is, for example, 7 μm or less, and may be 6 μm or less, 5 μm or less, or 4 μm or less. On the other hand, the thickness of the absorptive polarizing film 28 is, for example, 1 μm or more. The absorptive polarizing film 28 having such a thickness is typically formed on a substrate 53 and may be laminated on another member or layer while being integrated with the substrate 53. The substrate 53 may be appropriately selected depending on the absorptive polarizing film 28 to be formed on its main surface. A method for forming the absorptive polarizing film 28 on the substrate 53 will be described later.

[0016] The tensile modulus of elasticity of the protective film 54 is smaller than that of the substrate 53. Such a relationship allows the protective film 54 to be easily peeled off in a subsequent step. The tensile modulus of elasticity of the protective film is preferably 1.0×10 9 Pa, more preferably less than 8.0 × 10 8 Pa or less, and more preferably 6.0 × 10 8 The tensile modulus of the protective film is, for example, 1.0 × 10 8 Pa or more.

[0017] The thickness of the protective film 54 is, for example, 10 μm to 150 μm, preferably 20 μm to 100 μm, and more preferably 25 μm to 50 μm.

[0018] The haze of the protective film 54 may be 3% or more, or may be 5% or more. The difference between the haze of the protective film 54 and the haze of the substrate 53 may be 2% or more. The haze of the protective film 54 is, for example, 90% or less.

[0019] A film with adhesive properties (hereinafter referred to as a self-adhesive film) is preferably used as the protective film 54. A self-adhesive film can be temporarily attached to an object to be protected (e.g., the absorptive polarizing film 28) by static electricity. The use of such a film has the advantage of not leaving organic residues (e.g., glue stains caused by adhesive) on the object to be protected.

[0020] A polyolefin film is typically used as the self-adhesive film. Specifically, the self-adhesive film is preferably made of polyethylene, polypropylene, or a mixture thereof. Here, polyethylene includes ethylene homopolymers and copolymers of ethylene and other olefins. Polypropylene includes propylene homopolymers and copolymers of propylene and other olefins.

[0021] Specific examples of the polyethylene include high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (L-LDPE).

[0022] Examples of the other olefin include ethylene, propylene, butene, pentene, hexene, heptene, octene, nonene, and decene. Among these, ethylene, propylene, and butene are preferably used. In preparing a copolymer of ethylene or propylene with the other olefin, the blending ratio of the other olefin is preferably 40 parts by weight or less, more preferably 30 parts by weight or less, and even more preferably 20 parts by weight or less, per 100 parts by weight of the total of ethylene or propylene and the other olefin.

[0023] In one embodiment, the polyolefin film preferably contains polyethylene. Specifically, the polyolefin film is preferably a polyethylene film or a mixture film of polyethylene and polypropylene. When the polyolefin film contains a mixture of polyethylene and polypropylene, the content of polyethylene is preferably 60 parts by weight or more and 97 parts by weight or less, more preferably 70 parts by weight or more, and even more preferably 80 parts by weight or more, per 100 parts by weight of the total of polyethylene and polypropylene.

[0024] The self-adhesive film (e.g., polyolefin film) may contain other components such as particles, pigments, colorants, antistatic agents, UV absorbers, antioxidants, heat stabilizers, and chlorine scavengers. The self-adhesive film (e.g., polyolefin film) may be a single layer with a uniform composition, or may have a laminate structure of two or more layers with different compositions. Specific examples of laminate structures include a two-layer structure with a first layer and a second layer having different compositions, and a three-layer structure with a first layer, a second layer, and a third layer. The first layer and the third layer may have substantially the same composition or different compositions. The self-adhesive film (e.g., polyolefin film) may be a non-stretched film or a stretched film, but a non-stretched film is preferred.

[0025] The surface roughness Ra of the adhesive surface of the self-adhesive film (for example, polyolefin film) is, for example, 0.05 μm or more and 0.3 μm or less, and preferably 0.2 μm or less.

[0026] FIG. 1B shows how the first laminate 100 is cut into a desired shape (into sheets). The dashed lines in FIG. 1B indicate cutting lines. The planar shape of the first laminate 100 after cutting is, for example, rectangular or square. There are no particular limitations on the method for cutting the first laminate 100, but, for example, the first laminate 100 is cut using a punching blade. By cutting the absorptive polarizing film 28 in this manner with the protective film 54 attached, problems such as foreign matter adhering to the absorptive polarizing film 28 can be prevented.

[0027] FIG. 1C illustrates a process of bonding the absorptive polarizing film 28 of the first laminate 100 to a sheet-like second laminate 200. The sheet-like second laminate 200 has substantially the same shape in plan view as the first laminate 100 after cutting. The shape in plan view of the second laminate 200 is, for example, rectangular or square. The second laminate 200 includes a retardation member 30 having a first main surface 30a and a second main surface 30b facing each other, and a first pressure-sensitive adhesive layer 41 disposed on the first main surface 30a side. The retardation member 30 is typically a λ / 4 member. The second laminate 200 also includes a second pressure-sensitive adhesive layer 42 disposed on the second main surface 30b side, and a release liner 52 is bonded to the surface of the second pressure-sensitive adhesive layer 42. By laminating the first laminate 100 to the second laminate 200, for example, so that the planar viewing angles of both are aligned, the optical axis (e.g., absorption axis) of the absorptive polarizing film 28 and the optical axis (e.g., slow axis) of the phase difference member 30 can be aligned with high precision.

[0028] Before bonding the absorptive polarizing film 28 of the first laminate 100 to the first pressure-sensitive adhesive layer 41 of the second laminate 200, the protective film 54 is peeled off from the absorptive polarizing film 28. Because the protective film 54 has the above-mentioned predetermined tensile modulus, the protective film 54 can be peeled off from the absorptive polarizing film 28 while maintaining the very thin absorptive polarizing film 28 in close contact with the substrate 53. Peeling the substrate 53 from the absorptive polarizing film 28 during the peeling of the protective film 54 may result in a decrease in yield. Specifically, peeling of the substrate 53 may cause defects such as wrinkles, tears, and distortion at the edge of the first laminate 100, making it difficult to bond the corners together. As a result, it may be difficult to achieve precise axial alignment. Furthermore, after bonding the absorptive polarizing film 28 to the first pressure-sensitive adhesive layer 41, the substrate 53 may not provide sufficient protection for the absorptive polarizing film 28 during the next process. The peeling force of the protective film 54 against the absorptive polarizing film 28 is, for example, less than 0.01 N / 50 mm.

[0029] Although not shown, the surface of the first pressure-sensitive adhesive layer 41 may be protected by a release liner until the absorptive polarizing film 28 is attached to the first pressure-sensitive adhesive layer 41. The thickness of the release liner that protects the surface of the first pressure-sensitive adhesive layer 41 is preferably significantly different from the thickness of the release liner 52 that is attached to the surface of the second pressure-sensitive adhesive layer 42. For example, the difference between the thickness of the release liner that protects the surface of the first pressure-sensitive adhesive layer 41 and the thickness of the release liner 52 that is attached to the surface of the second pressure-sensitive adhesive layer 42 is preferably 7 μm or more, and more preferably 10 μm or more. Making the release liners arranged on both sides of the retardation member 30 different in thickness makes it easier to distinguish between the front and back of the retardation member 30, which can contribute to improving workability.

[0030] Unlike the illustrated example, when the first pressure-sensitive adhesive layer 41 is provided in advance on the absorptive polarizing film 28 side rather than on the retardation member 30 side (when the first laminate 100 has the first pressure-sensitive adhesive layer 41), it may be necessary to separately manage the product of the first laminate 100. Specifically, depending on the materials constituting the first pressure-sensitive adhesive layer 41 and / or the absorptive polarizing film 28, it may become necessary to manage the expiration date of the first laminate 100.

[0031] Although not shown, after the absorptive polarizing film 28 is bonded to the first pressure-sensitive adhesive layer 41, another member (including a layer) may be laminated thereon. For example, after the substrate 53 is peeled from the absorptive polarizing film 28, another member may be laminated on the absorptive polarizing film 28. The peel force of the substrate 53 from the absorptive polarizing film 28 is, for example, 0.01 N / 50 mm to 0.06 N / 50 mm. The another member laminated on the absorptive polarizing film 28 may also be in the form of a sheet. The another member may have, for example, substantially the same shape as the first laminate 100 in a plan view.

[0032] The thickness of the first pressure-sensitive adhesive layer 41 and the second pressure-sensitive adhesive layer 42 can each be set to any appropriate thickness, but is preferably 3 μm to 20 μm, and more preferably 4 μm to 15 μm. For example, the thickness of the second pressure-sensitive adhesive layer 42 can be set to be greater than the thickness of the first pressure-sensitive adhesive layer 41. By providing a thickness difference, for example, in the second laminate 200, it becomes easier to distinguish between the first main surface 30a side and the second main surface 30b side of the retardation member 30. The difference in thickness between the second pressure-sensitive adhesive layer 42 and the first pressure-sensitive adhesive layer 41 is, for example, 5 μm or more.

[0033] The components (e.g., a phase difference component and / or a polarizing component) that can be included in the first laminate and the second laminate can have optical axes. By preparing the first laminate and the second laminate in a sheet form in advance and laminating them, highly accurate axial alignment is possible. The optical laminate with highly accurate axial alignment can be used in any appropriate image display device. For example, it can be suitably used in VR goggles. VR goggles require extremely high accuracy in axial alignment of the optical axes of the components included in the optical laminate.

[0034] FIG. 2 is a schematic diagram showing the overall configuration of an example of a display system for VR goggles, illustrating the arrangement and shape of each component of the display system. The display system 10 includes a display element 12, a reflective polarizing element 14, a first lens unit 16, a half mirror 18, a first λ / 4 element 20, a second λ / 4 element 22, and a second lens unit 24. The reflective polarizing element 14 is disposed in front of the display surface 12a of the display element 12 and can reflect light emitted from the display element 12. The first lens unit 16 is disposed on the optical path between the display element 12 and the reflective polarizing element 14, and the half mirror 18 is disposed between the display element 12 and the first lens unit 16. The first λ / 4 element 20 is disposed on the optical path between the display element 12 and the half mirror 18, and the second λ / 4 element 22 is disposed on the optical path between the half mirror 18 and the reflective polarizing element 14.

[0035] The display element 12 is, for example, a liquid crystal display or an organic EL display, and has a display surface 12a for displaying an image. The light emitted from the display surface 12a passes through, for example, a polarizing member that may be included in the display element 12, and is converted into a first linearly polarized light.

[0036] The first λ / 4 member 20 can convert the first linearly polarized light incident on the first λ / 4 member 20 into first circularly polarized light. The first λ / 4 member 20 may be provided integrally with the display element 12.

[0037] The half mirror 18 transmits the light emitted from the display element 12 and reflects the light reflected by the reflective polarizing member 14 back toward the reflective polarizing member 14. The half mirror 18 is provided integrally with the first lens portion 16.

[0038] The second λ / 4 member 22 can transmit light reflected by the reflective polarizing member 14 and the half mirror 18 through the reflective polarizing member 14. The second λ / 4 member 22 may be provided integrally with the first lens portion 16.

[0039] The first circularly polarized light output from the first λ / 4 element 20 passes through the half mirror 18 and the first lens unit 16, and is converted into the second linearly polarized light by the second λ / 4 element 22. The second linearly polarized light output from the second λ / 4 element 22 is reflected toward the half mirror 18 without passing through the reflective polarizing element 14. At this time, the polarization direction of the second linearly polarized light incident on the reflective polarizing element 14 is the same as the reflection axis of the reflective polarizing element 14. Therefore, the second linearly polarized light incident on the reflective polarizing element 14 is reflected by the reflective polarizing element 14.

[0040] The second linearly polarized light reflected by the reflective polarizing element 14 is converted into second circularly polarized light by the second λ / 4 element 22, and the second circularly polarized light emitted from the second λ / 4 element 22 passes through the first lens unit 16 and is reflected by the half mirror 18. The second circularly polarized light reflected by the half mirror 18 passes through the first lens unit 16 and is converted into third linearly polarized light by the second λ / 4 element 22. The third linearly polarized light is transmitted through the reflective polarizing element 14. At this time, the polarization direction of the third linearly polarized light incident on the reflective polarizing element 14 is the same as the transmission axis of the reflective polarizing element 14. Therefore, the third linearly polarized light incident on the reflective polarizing element 14 is transmitted through the reflective polarizing element 14.

[0041] The light transmitted through the reflective polarizing member 14 passes through the second lens portion 24 and enters the eye 26 of the user.

[0042] The absorption axis of the polarizing member included in the display element 12 and the reflection axis of the reflective polarizing member 14 may be disposed approximately parallel to each other or approximately perpendicular to each other. The angle formed between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the first λ / 4 member 20 is, for example, 40° to 50°, or may be 42° to 48°, or may be approximately 45°. The angle formed between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the second λ / 4 member 22 is, for example, 40° to 50°, or may be 42° to 48°, or may be approximately 45°.

[0043] The in-plane retardation Re(550) of the first λ / 4 component 20 is, for example, 100 nm to 190 nm, or alternatively, 110 nm to 180 nm, 130 nm to 160 nm, or 135 nm to 155 nm. The first λ / 4 component 20 preferably exhibits inverse dispersion wavelength characteristics in which the retardation value increases according to the wavelength of the measurement light. The Re(450) / Re(550) of the first λ / 4 component 20 may be, for example, 0.75 or more and less than 1, or 0.8 or more and 0.95 or less.

[0044] The in-plane retardation Re(550) of the second λ / 4 component 22 is, for example, 100 nm to 190 nm, or alternatively, 110 nm to 180 nm, 130 nm to 160 nm, or 135 nm to 155 nm. The second λ / 4 component 22 preferably exhibits inverse dispersion wavelength characteristics in which the retardation value increases according to the wavelength of the measurement light. The Re(450) / Re(550) of the second λ / 4 component 22 may be, for example, 0.75 or more and less than 1, or 0.8 or more and 0.95 or less.

[0045] The optical laminate may include, for example, components included in the display system. Specifically, the optical laminate may include a phase difference component such as a λ / 4 component. The optical laminate may also include a polarizing component such as a reflective polarizing component or an absorptive polarizing film. The optical laminate may also include other components such as a protective component and an adhesive layer for integrating adjacent components. The thickness of the optical laminate may vary depending on, for example, the type and number of components included, but is, for example, 50 μm to 400 μm.

[0046] 3 is a schematic cross-sectional view showing an example of the details of an optical laminate. The optical laminate 1 includes a reflective polarizing element 14. The optical laminate 1 further includes an absorptive polarizing film 28 that can be disposed between the reflective polarizing element 14 and the second lens portion 24, for example, from the viewpoint of improving visibility. The absorptive polarizing film 28 is laminated in front of the reflective polarizing element 14 via a pressure-sensitive adhesive layer 43. The reflection axis of the reflective polarizing element 14 and the absorption axis of the absorptive polarizing film 28 can be disposed approximately parallel to each other, and the transmission axis of the reflective polarizing element 14 and the transmission axis of the absorptive polarizing film 28 can be disposed approximately parallel to each other.

[0047] The optical laminate 1 further includes a third λ / 4 member 30 that can be disposed between the absorptive polarizing film 28 and the second lens section 24. The third λ / 4 member 30 is laminated to the absorptive polarizing film 28 via a first pressure-sensitive adhesive layer 41. The angle between the absorption axis of the absorptive polarizing film 28 and the slow axis of the third λ / 4 member 30 is, for example, 40° to 50°, or may be 42° to 48°, or approximately 45°. By providing such a member, for example, it is possible to prevent reflection of external light from the second lens section 24 side. The in-plane retardation Re(550) of the third λ / 4 member 30 is, for example, 100 nm to 190 nm, or may be 110 nm to 180 nm, 130 nm to 160 nm, or 135 nm to 155 nm. The third λ / 4 member 30 preferably exhibits inverse dispersion wavelength characteristics in which the retardation value increases according to the wavelength of the measurement light. The Re(450) / Re(550) of the third λ / 4 member is, for example, not less than 0.75 and less than 1, and may be not less than 0.8 and not more than 0.95.

[0048] The optical laminate 1 includes, for example, a second pressure-sensitive adhesive layer 42 for integration with an adherend (for example, the second lens portion 24), and a release liner 52 is attached to the surface of the second pressure-sensitive adhesive layer 42. For example, the release liner 52 can protect the second pressure-sensitive adhesive layer 42.

[0049] 3, the optical laminate 1 may further include a protective member 31 that can be placed behind the reflective polarizing member 14. The protective member 31 is laminated to the reflective polarizing member 14 via a pressure-sensitive adhesive layer 44.

[0050] In the illustrated example, the optical laminate 1 includes a surface protection film 51 removably attached to the protective member 31. The surface protection film 51 may be peeled off before the optical laminate 1 is put into use (for example, before being laminated on the second lens portion 24) or during the manufacturing process of the final product (for example, VR goggles), or may be mounted directly on the final product.

[0051] The optical laminate 1 can be manufactured by the above manufacturing method. Specifically, after forming a laminated portion from the absorption-type polarizing film 28 to the release liner 52 according to the above manufacturing process example, the optical laminate 1 can be obtained by laminating the reflective polarizing member 14 and the protective member 31 on this laminated portion. The optical laminate 1 can be cut into a shape corresponding to the shape of the first lens portion or the second lens portion of the above display system, for example. For example, the optical laminate 1 can be cut into a substantially elliptical shape, a substantially circular shape, or the like. Then, the optical laminate 1 can be integrally provided on the first lens portion or the second lens portion.

[0052] The above λ / 4 member preferably exhibits a refractive index characteristic relationship of nx > ny ≧ nz. Here, "ny = nz" includes not only the case where ny and nz are exactly equal but also the case where they are substantially equal. Therefore, within a range that does not impair the effects of the present invention, ny < nz may occur. The Nz coefficient of the λ / 4 member is preferably 0.9 to 3, more preferably 0.9 to 2.5, still more preferably 0.9 to 1.5, and particularly preferably 0.9 to 1.3.

[0053] The λ / 4 member can be, for example, a stretched film of a resin film or an alignment and solidification layer of a liquid crystal compound.

[0054] Examples of the resin contained in the above resin film include polycarbonate resins, polyester carbonate resins, polyester resins, polyvinyl acetal resins, polyarylate resins, cyclic olefin resins, cellulose resins, polyvinyl alcohol resins, polyamide resins, polyimide resins, polyether resins, polystyrene resins, acrylic resins, and the like. These resins may be used alone or in combination. Examples of the combination method include blending and copolymerization. When the λ / 4 member exhibits reverse dispersion wavelength characteristics, a resin film containing a polycarbonate resin or a polyester carbonate resin (hereinafter sometimes simply referred to as a polycarbonate resin) can be preferably used.

[0055] Any suitable polycarbonate-based resin can be used as the polycarbonate-based resin. For example, the polycarbonate-based resin contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, and structural units derived from at least one dihydroxy compound selected from the group consisting of alicyclic diols, alicyclic dimethanols, di-, tri-, or polyethylene glycols, and alkylene glycols or spiroglycols. Preferably, the polycarbonate-based resin contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, structural units derived from an alicyclic dimethanol, and / or structural units derived from di-, tri-, or polyethylene glycol; more preferably, it contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, and structural units derived from di-, tri-, or polyethylene glycol. The polycarbonate-based resin may contain structural units derived from other dihydroxy compounds as needed. Details of polycarbonate-based resins suitable for use in λ / 4 components and methods for forming λ / 4 components are described, for example, in JP 2014-10291 A, JP 2014-26266 A, JP 2015-212816 A, JP 2015-212817 A, and JP 2015-212818 A, and the descriptions in these publications are incorporated herein by reference.

[0056] The thickness of the λ / 4 member made of a stretched resin film is, for example, 10 μm to 100 μm, preferably 10 μm to 70 μm, and more preferably 20 μm to 60 μm.

[0057] The above-mentioned liquid crystal compound alignment solidified layer is a layer in which the liquid crystal compound is aligned in a predetermined direction within the layer and the alignment state is fixed. The term "alignment solidified layer" encompasses an alignment solidified layer obtained by solidifying a liquid crystal monomer, as described below. In a λ / 4 component, rod-shaped liquid crystal compounds are typically aligned in the slow axis direction of the λ / 4 component (homogeneous alignment). Examples of rod-shaped liquid crystal compounds include liquid crystal polymers and liquid crystal monomers. The liquid crystal compound is preferably polymerizable. If the liquid crystal compound is polymerizable, the alignment state of the liquid crystal compound can be fixed by aligning the liquid crystal compound and then polymerizing it.

[0058] The alignment and solidification layer of the liquid crystal compound (liquid crystal alignment and solidification layer) can be formed by performing an alignment treatment on the surface of a predetermined substrate, applying a coating liquid containing a liquid crystal compound to the surface to align the liquid crystal compound in a direction corresponding to the alignment treatment, and fixing the alignment state. Any appropriate alignment treatment can be used as the alignment treatment. Specific examples include mechanical alignment treatment, physical alignment treatment, and chemical alignment treatment. Specific examples of mechanical alignment treatment include rubbing treatment and stretching treatment. Specific examples of physical alignment treatment include magnetic field alignment treatment and electric field alignment treatment. Specific examples of chemical alignment treatment include oblique vapor deposition and photoalignment treatment. Any appropriate treatment conditions can be used for the various alignment treatments depending on the purpose.

[0059] The alignment of liquid crystal compounds is achieved by treating them at a temperature at which they exhibit a liquid crystal phase depending on the type of liquid crystal compound. By performing such temperature treatment, the liquid crystal compounds assume a liquid crystal state and are aligned in accordance with the alignment treatment direction of the substrate surface.

[0060] In one embodiment, the alignment state is fixed by cooling the liquid crystal compound aligned as described above. When the liquid crystal compound is polymerizable or crosslinkable, the alignment state is fixed by subjecting the liquid crystal compound aligned as described above to a polymerization treatment or crosslinking treatment.

[0061] Any suitable liquid crystal polymer and / or liquid crystal monomer can be used as the liquid crystal compound. The liquid crystal polymer and the liquid crystal monomer can be used alone or in combination. Specific examples of liquid crystal compounds and methods for producing a liquid crystal alignment solidified layer are described in, for example, JP 2006-163343 A, JP 2006-178389 A, and WO 2018 / 123551 A. The descriptions in these publications are incorporated herein by reference.

[0062] The thickness of the second λ / 4 member formed of the liquid crystal alignment solidified layer is, for example, 1 μm to 10 μm, preferably 1 μm to 8 μm, more preferably 1 μm to 6 μm, and even more preferably 1 μm to 4 μm.

[0063] The reflective polarizing element transmits polarized light parallel to its transmission axis (typically, linearly polarized light) while maintaining its polarization state, and can reflect light in other polarization states. The reflective polarizing element is typically made of a film (sometimes referred to as a reflective polarizing film) having a multilayer structure. In this case, the thickness of the reflective polarizing element is, for example, 10 μm to 150 μm, preferably 20 μm to 100 μm, and more preferably 30 μm to 60 μm.

[0064] FIG. 4 is a schematic perspective view showing an example of a multilayer structure included in a reflective polarizing film. The multilayer structure 14a has alternating birefringent layers A and layers B that are substantially not birefringent. The total number of layers constituting the multilayer structure may be 50 to 1000. For example, the refractive index nx in the x-axis direction of layer A is larger than the refractive index ny in the y-axis direction, and the refractive index nx in the x-axis direction and the refractive index ny in the y-axis direction of layer B are substantially the same, and the refractive index difference between layer A and layer B is large in the x-axis direction and substantially zero in the y-axis direction. As a result, the x-axis direction can be the reflection axis, and the y-axis direction can be the transmission axis. The refractive index difference between layer A and layer B in the x-axis direction is preferably 0.2 to 0.3.

[0065] The A layer is typically made of a material that exhibits birefringence upon stretching. Examples of such materials include naphthalenedicarboxylic acid polyesters (e.g., polyethylene naphthalate), polycarbonates, and acrylic resins (e.g., polymethyl methacrylate). The B layer is typically made of a material that does not substantially exhibit birefringence upon stretching. Examples of such materials include copolyesters of naphthalenedicarboxylic acid and terephthalic acid. The multilayer structure can be formed by a combination of coextrusion and stretching. For example, the materials constituting the A layer and the B layer are extruded and then multilayered (e.g., using a multiplier). The resulting multilayer laminate is then stretched. The x-axis direction in the illustrated example corresponds to the stretching direction.

[0066] Commercially available reflective polarizing films include, for example, "DBEF" and "APF" manufactured by 3M, and "APCF" manufactured by Nitto Denko Corporation.

[0067] The crossed transmittance (Tc) of the reflective polarizing member (reflective polarizing film) can be, for example, 0.001% to 3%. The single transmittance (Ts) of the reflective polarizing member (reflective polarizing film) can be, for example, 43% to 49%, preferably 45% to 47%. The polarization degree (P) of the reflective polarizing member (reflective polarizing film) can be, for example, 92% to 99.99%.

[0068] The crossed transmittance, single transmittance, and degree of polarization can be measured, for example, using an ultraviolet-visible spectrophotometer. The degree of polarization P can be calculated from the obtained Tp and Tc by measuring the single transmittance Ts, parallel transmittance Tp, and crossed transmittance Tc using an ultraviolet-visible spectrophotometer, using the following formula. Note that Ts, Tp, and Tc are Y values ​​measured using a 2-degree visual field (C light source) according to JIS Z 8701 and corrected for luminosity. Polarization degree P(%)={(Tp-Tc) / (Tp+Tc)} 1 / 2 ×100

[0069] As described above, an absorptive polarizing film is typically composed of a film containing a dichroic material such as iodine or an organic dye. The crossed transmittance (Tc) of the absorptive polarizing film is preferably 0.5% or less, more preferably 0.1% or less, and even more preferably 0.05% or less. The single transmittance (Ts) of the absorptive polarizing film is, for example, 41.0% to 45.0%, and preferably 42.0% or more. The polarization degree (P) of the absorptive polarizing film is, for example, 99.0% to 99.997%, and preferably 99.8% or more.

[0070] For example, the absorptive polarizing film may be made of a liquid crystal compound. The thickness of the absorptive polarizing film made of a liquid crystal compound may be, for example, 4 μm or less, or may be 3 μm or less, or may be 2 μm or less.

[0071] As the liquid crystal compound, a lyotropic liquid crystal polymer is preferably used. The liquid crystal compound is typically aligned in a predetermined direction in the absorptive polarizing film, and the alignment state is fixed. Specifically, the absorptive polarizing film can be a layer in which the alignment of the liquid crystal compound is fixed. The liquid crystal phase of the liquid crystal compound may be, for example, any of a nematic phase, a smectic phase, and a columnar phase.

[0072] The lyotropic liquid crystalline polymer has, for example, a structural unit containing a ring structure, a linking group, and a sulfo group and / or a sulfonate group. The ring structure is typically contained in the main chain of the lyotropic liquid crystalline polymer. The number of ring structures contained in each structural unit is, for example, 1 or more and 5 or less. A typical example of the ring structure is an aromatic ring. Examples of the ring structure include a benzene ring, an oxazole ring, a thiazole ring, an oxadiazole ring, a biphenyl ring, and condensed rings thereof. A benzene ring is preferably used. The linking group links, for example, two ring structures. Both ends of the linking group are, for example, directly bonded to the ring structures. Examples of the linking group include sp 3 Carbon-containing linking groups include amide bonds. 3 A carbon-containing linking group is used. 3Specific examples of the carbon-containing linking group include alkylene groups and oxyalkylene groups. Preferably, alkylene groups having 1 to 8 carbon atoms are used, and more preferably, methylene groups and ethylene groups are used.

[0073] The sulfo group and / or sulfonate group can impart water solubility and lyotropic liquid crystallinity to the lyotropic liquid crystalline polymer. The sulfo group and / or sulfonate group is, for example, directly bonded to the ring structure. The number of sulfo groups and / or sulfonate groups contained in each structural unit is, for example, 1 to 5. Representative examples of the counter cation of the sulfonate group include alkali metal cations, and preferably Li + , Na + , K. + , Rb + , Cs + By exchanging the counter cation of the sulfonate group for a cation with lower water solubility (so-called insolubilization treatment), an absorptive polarizing film with excellent water resistance can be obtained. Typical examples of cations with lower water solubility than alkali metal cations include ammonium ions and polyvalent metal cations. Typical ammonium ions used are ammonium ions of organic nitrogen compounds having two or more nitrogen atoms in the molecule. The number of nitrogen atoms contained in the organic nitrogen compound is not particularly limited, but is preferably 2 to 5, more preferably 2 to 3, and even more preferably 2. Examples of polyvalent metal cations include alkaline earth metal cations (e.g., Ca 2+ , Mg 2+ , Sr 2+ , Ba 2+ ), transition metal cations (e.g., La 3+ , Fe 3+ , Cr 3+ , Mn 2+ , Cu 2+ , Ce 3+ ), poor metal cations (e.g., Al 3+ , Pb 2+ , Sn 2+ , Zn 2+ ) are mentioned.

[0074] Examples of structural units of lyotropic liquid crystalline polymers include structures shown in the following formulas (1) to (23). Here, formulas (1), (3) to (10) represent structural units having an alkylene group (linking group) and a benzene ring (ring structure). Formula (2) represents a structural unit having an amide bond (linking group) and a benzene ring (ring structure). Formulas (11) to (19) represent structural units having an alkylene group (linking group) and a fused ring (ring structure). Formulas (20) to (23) represent structural units having an oxyalkylene group (linking group) and a benzene ring (ring structure). For convenience, formulas (2) to (23) below contain a sulfo group, but a sulfonate group may also be used.

[0075] [ka] (In formula (1), X represents a hydrogen atom or a counter cation selected from an ammonium ion, an alkali metal cation, an alkaline earth metal cation, a transition metal cation, or a poor metal cation.)

[0076] [ka]

[0077] [ka]

[0078] [ka]

[0079] [ka]

[0080] Among these structural units, structural units having an alkylene group (linking group) and a benzene ring (ring structure) (the above formulas (1), (3) to (10)) and structural units having an amide bond (linking group) and a benzene ring (ring structure) (the above formula (2)) are preferably used, with the structural unit represented by the above formula (1) being more preferably used. The lyotropic liquid crystalline polymer may, for example, have one of the above structural units alone, or may have a combination of multiple structural units. The lyotropic liquid crystalline polymer is preferably a homopolymer having one of the above structural units alone, more preferably a homopolymer of a structural unit represented by the above formula (1) or (2), and even more preferably a homopolymer of a structural unit represented by the above formula (1).

[0081] In the lyotropic liquid crystalline polymer, the number of repeating constitutional units is, for example, 25 to 1000. The lyotropic liquid crystalline polymer itself can be transparent and does not substantially exhibit absorption dichroism. The single transmittance of the lyotropic liquid crystalline polymer is, for example, 85% to 100%.

[0082] In one embodiment, the absorptive polarizing film made of a liquid crystal compound may contain, as a dichroic material, an organic dye capable of imparting absorptive dichroism. Examples of such organic dyes include those represented by the following formulas (24) to (26). [ka] In formula (24), A represents a sulfo group or a sulfonate group. m represents 1 or more and 4 or less. B represents a chlorine atom. p represents 0 or more and 2 or less. m+p is 4 or less. When A is a sulfonate group, its counter cation is Na + , K. + , Cs + , or NH4 + ) [ka] In formula (25), A represents a sulfo group or a sulfonate group. m represents 1 or more and 4 or less. B represents a hydroxyl group. p represents 0 or more and 4 or less. C represents a sulfonyl group. n represents 0 or more and 2 or less. R represents an oxygen atom. q represents 0 or more and 4 or less. m+p+q is 6 or less. When A is a sulfonate group, its counter cation is Na + , K. + , Cs + , or NH4 + ) [ka] In formula (26), A represents a sulfo group or a sulfonate group. When A represents a sulfonate group, its counter cation is Na + , K. + , Cs + , or NH4 + )

[0083] Further, examples of organic dyes include azo dyes, azoxy dyes, azomethine dyes, stilbene dyes, polymethine dyes, cationic dyes, naphthalene dyes, perylene dyes, and anthrone dyes described in paragraphs

[0035] to

[0037] of JP-A No. 2004-528603; stilbene dyes described in U.S. Pat. No. 5,007,942 or U.S. Pat. No. 5,340,504; and azo and metallized dyes described in European Patent No. 0 530 106, European Patent Application Publication No. 0 626 598, or U.S. Pat. No. 5,318,856.

[0084] In addition, examples of organic dyes include CI Direct Yellow 12, CI Direct Yellow 28, CI Direct Yellow 44, CI Direct Yellow 142, CI Direct Orange 6, CI Direct Orange 26, CI Direct Orange 39, CI Direct Orange 72, CI Direct Orange 107, CI Direct Red 2, CI Direct Red 31, CI Direct Red 79, CI Direct Red 81, CI Direct Red 240, CI Direct Red 247, CI Direct Violet 9, CI Direct Violet 48, CI Direct Violet 51, CI Direct Blue 1, CI Direct Blue 15, CI Direct Blue 71, CI Direct Blue 78, CI Direct Blue 98, CI Direct Blue 168, CI Direct Blue 202, CI Direct Blue 169, CI Direct Blue 170, CI Direct Blue 171, CI Direct Blue 172, CI Direct Blue 173, CI Direct Blue 174, CI Direct Blue 175, CI Direct Blue 176, CI Direct Blue 177, CI Direct Blue 178, CI Direct Blue 179 ... Direct dyes such as Direct Brown 106, CI Direct Brown 223, and CI Direct Green 85; reactive dyes such as Active Yellow 1, Active Red 1, Active Red 6, Active Red 14, Active Red 46, Active Violet 1, Active Blue 9, and Active Blue 10; acid dyes such as Acid Orange 63, Acid Red 85, Acid Red 144, Acid Red 152, Acid Brown 32, Acid Violet 50, Acid Blue 18, Acid Blue 44, Acid Blue 61, Acid Blue 102, and Acid Black 21; and cationic dyes such as Basic Red 12, Basic Brown (CI 33500), and Basic Black.

[0085] Further examples of organic dyes include organic molecules described in U.S. Patent Application Publication No. 2001 / 0029638. Specific examples include polymethine dyes (e.g., pseudoisocyanine, piacyanol), triarylmethane dyes (e.g., Basic Turquose, Acid Light Blue 3), diaminoxanthene dyes (e.g., sulforhodamine), acridine dyes (e.g., Basic Yellow K), sulfonated acridine dyes (e.g., trans-quinacridone), water-soluble derivatives of anthraquinone dyes (e.g., Activite Light Blue KX), sulfonated vat dyes (e.g., flavanthrone, indanthrene yellow, vat yellow 4K, vat dark green G, vat violet C, indanthrone, perylene violet, vat scarlet 2G), and azo dyes (e.g., benzopurpurin 4B, Direct Lightfast Yellow). O), water-soluble diazine dyes (e.g., Acid Dark Blue 3), sulfonated dioxazine dyes (e.g., Pigment Violet Dioxazine), soluble thiazine dyes (e.g., Methylene Blue), water-soluble phthalocyanine derivatives (e.g., copper octacarboxyphthalocyanine salts), cromoglycate disodium, perylenetetracarboxylic diimide red (PADR), benzimidazoles of PADR (i.e., purple), naphthalenetetracarboxylic acid (i.e., yellow, deep red-purple), phenanthro-9',10':2,3-quinoxaline, and sulfoderivatives of benzimidazoles.

[0086] Such organic dyes can be used alone or in combination of two or more. In a preferred embodiment, the organic dyes represented by the above formulas (24) to (26) are used in combination.

[0087] An absorptive polarizing film made of a liquid crystal compound can be obtained, for example, by coating a liquid crystal polymer solution prepared by dissolving the above-mentioned lyotropic liquid crystalline polymer in an aqueous solvent on a substrate, drying the liquid crystal polymer solution, and then dyeing the lyotropic liquid crystal layer. After dyeing, excess dye solution can be removed.

[0088] The thickness of the substrate is, for example, 10 μm to 80 μm. The tensile modulus of the substrate is preferably 1.0×10 9 Pa or more, more preferably 1.2 × 10 9 Pa or more, and more preferably 1.5 × 10 9 The tensile modulus of the substrate is, for example, 1.0 × 10 10 The haze of the substrate is, for example, 2% or less. The substrate can be composed of any appropriate film. Examples of materials that can be used as the main component of the film constituting the substrate include cellulose resins such as triacetyl cellulose (TAC), polyesters such as polyethylene terephthalate (PET), polyvinyl alcohols, polycarbonates, polyamides, polyimides, polyethersulfones, polysulfones, polystyrenes, and cycloolefins such as polynorbornene, polyolefins, (meth)acrylics, and acetates. For example, a TAC film or a PET film is preferably used as the substrate. Such a film satisfies the above tensile modulus and has advantages such as being less likely to deform during the coating and drying process and being less likely to develop defects such as dents and scratches when wound up after coating and drying. On the other hand, when used on a substrate that is less likely to deform, it tends to be difficult to peel the substrate from the absorptive polarizing film after formation. This tendency can become more pronounced when the resulting absorptive polarizing film is very thin.

[0089] Examples of the aqueous solvent include water and a mixed solvent of water and alcohol, with water being preferred. The solids concentration in the liquid crystal polymer solution is, for example, 5% by mass to 30% by mass, preferably 10% by mass to 20% by mass. When applying the liquid crystal polymer solution, a primer layer (e.g., containing polyethyleneimine) may be formed on the coated surface of the substrate. The thickness of the primer layer is, for example, 10 nm to 50 nm. The liquid crystal polymer solution can be applied by a coating method capable of applying shear stress. A wire bar is typically used for application. A lyotropic liquid crystal layer can be formed by drying the coated film of the liquid crystal polymer solution. The drying temperature is, for example, 40°C to 80°C, preferably 50°C to 70°C. The drying time is, for example, 10 seconds to 10 minutes, preferably 5 minutes or less. The lyotropic liquid crystal polymer can be oriented by the shear stress during application, and the lyotropic liquid crystal layer can exhibit retardation with a slow axis in the coating direction.

[0090] The dyeing can be typically performed by immersing the lyotropic liquid crystal layer in a dye solution containing a dichroic material. The temperature of the dye solution during dyeing is, for example, from 10° C. to 50° C., preferably from 20° C. to 40° C. The immersion time (dyeing time) is, for example, from 5 seconds to 300 seconds, preferably from 30 seconds to 180 seconds.

[0091] When the dichroic substance is iodine, the dye solution preferably further contains an iodine compound, more preferably an iodine compound and a polyvalent metal salt. Examples of iodine compounds include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Potassium iodide is preferably used. The mass ratio of iodine to the iodine compound (iodine:iodine compound) in the dye solution is, for example, 1:5 to 1:30, preferably 1:5 to 1:15. By including a polyvalent metal salt in the dye solution, water resistance can be imparted to the absorptive polarizing film. Examples of polyvalent metal salts include chlorides, sulfates, nitrates, phosphates, oxalates, and acetates. Examples of counter metals for polyvalent metal salts include alkali metals, alkaline earth metals, transition metals, and non-metallic metals, specifically barium, aluminum, lead, chromium, strontium, cerium, lanthanum, samarium, yttrium, copper, and iron. Strontium chloride is preferably used. The mass ratio of iodine to polyvalent metal salt (iodine:polyvalent metal salt) in the dye solution is, for example, 1:5 to 1:30, and preferably 1:5 to 1:15.

[0092] When the dichroic material is an organic dye, the solids concentration of the organic dye in the dye solution is, for example, 0.1% by mass to 3.0% by mass, and preferably 1.0% by mass or more. When organic dyes represented by the above formulas (24) to (26) are used in combination, the mass ratio of formula (24):formula (25):formula (26) is, for example, 40-60:10-30:10-30.

[0093] Furthermore, for example, the absorptive polarizing film may be made of a resin film, and in this case, the absorptive polarizing film is preferably a polyvinyl alcohol (PVA) film containing iodine.

[0094] An example of a method for producing an absorptive polarizing film made of a resin film includes forming a polyvinyl alcohol-based resin layer (PVA-based resin layer) containing a polyvinyl alcohol-based resin (PVA-based resin) and a halide on one side of a long thermoplastic resin substrate to form a laminate, and subjecting the laminate to an in-air auxiliary stretching treatment, a dyeing treatment, an underwater stretching treatment, and a drying shrinkage treatment in which the laminate is heated while being transported in the longitudinal direction to shrink the laminate by 2% or more in the width direction, in this order. The thickness of the resulting absorptive polarizing film can be controlled, for example, by adjusting the stretching ratio in the underwater stretching treatment.

[0095] The PVA-based resin layer is preferably formed by applying a coating liquid containing a PVA-based resin and a halide to a thermoplastic resin substrate and drying the coating liquid. The content of the halide in the PVA-based resin layer is preferably 5 to 20 parts by weight per 100 parts by weight of the PVA-based resin. The thickness of the PVA-based resin layer is preferably 3 to 40 μm, and more preferably 3 to 20 μm.

[0096] Examples of methods for applying the coating liquid include roll coating, spin coating, wire bar coating, dip coating, die coating, curtain coating, spray coating, knife coating (comma coating, etc.), etc. The application and drying temperature of the coating liquid is preferably 50°C or higher.

[0097] From the viewpoint of improving the adhesion between the thermoplastic resin substrate and the PVA-based resin layer, the thermoplastic resin substrate may be subjected to a surface treatment such as a corona treatment before forming the PVA-based resin layer, or an easy-adhesion layer may be formed on the thermoplastic resin substrate.

[0098] The thickness of the thermoplastic resin substrate is preferably 20 μm to 300 μm, more preferably 50 μm to 200 μm. If the thickness is less than 20 μm, for example, it may be difficult to form a PVA-based resin layer. If the thickness is more than 300 μm, for example, in the underwater stretching treatment described below, it may take a long time for the thermoplastic resin substrate to absorb water, and an excessive load may be required for stretching.

[0099] The water absorption of the thermoplastic resin substrate is preferably 0.2% or more, more preferably 0.3% or more. The thermoplastic resin substrate can absorb water, which acts as a plasticizer to plasticize the substrate. As a result, the stretching stress can be significantly reduced, allowing for high stretching ratios. The water absorption of the thermoplastic resin substrate is preferably 3.0% or less, more preferably 1.0% or less. Use of such a thermoplastic resin substrate can prevent problems such as a significant decrease in the dimensional stability of the substrate during production, resulting in poor appearance of the resulting absorptive polarizing film. Furthermore, it can prevent breakage of the substrate and peeling of the PVA-based resin layer from the substrate during underwater stretching. The water absorption of the thermoplastic resin substrate can be adjusted, for example, by introducing a modifying group into the constituent materials. The water absorption is a value determined in accordance with JIS K 7209.

[0100] The glass transition temperature (Tg) of the thermoplastic resin substrate is preferably 120°C or lower. By using such a thermoplastic resin substrate, the stretchability of the laminate can be sufficiently ensured while suppressing crystallization of the PVA-based resin layer. Considering the plasticization of the thermoplastic resin substrate with water and the smooth underwater stretching, the Tg is more preferably 100°C or lower, and even more preferably 90°C or lower. On the other hand, the Tg of the thermoplastic resin substrate is preferably 60°C or higher. By using such a thermoplastic resin substrate, defects such as deformation of the substrate (e.g., the occurrence of unevenness, sagging, wrinkles, etc.) during the application and drying of the coating liquid can be prevented, allowing for the production of a satisfactory laminate. Furthermore, the PVA-based resin layer can be stretched at a suitable temperature (e.g., about 60°C). The glass transition temperature of the thermoplastic resin substrate can be adjusted, for example, by introducing a modifying group into the constituent material or by heating using a crystallizing material. The glass transition temperature (Tg) is a value determined in accordance with JIS K 7121.

[0101] Examples of thermoplastic resins include ester resins such as polyethylene terephthalate resins, cycloolefin resins such as norbornene resins, olefin resins such as polypropylene, polyamide resins, polycarbonate resins, and copolymer resins thereof. Among these, norbornene resins and amorphous polyethylene terephthalate resins are preferably used.

[0102] In one embodiment, an amorphous (non-crystallized) polyethylene terephthalate resin is preferably used. Among them, an amorphous (hard to crystallize) polyethylene terephthalate resin is preferably used. Specific examples of the amorphous polyethylene terephthalate resin include copolymers further containing isophthalic acid and / or cyclohexanedicarboxylic acid as dicarboxylic acids, and copolymers further containing cyclohexanedimethanol or diethylene glycol as glycols.

[0103] In a preferred embodiment, the thermoplastic resin substrate is composed of a polyethylene terephthalate resin having an isophthalic acid unit. Such a thermoplastic resin substrate has excellent stretchability and can suppress crystallization during stretching. This is thought to be due to the introduction of the isophthalic acid unit, which imparts a large curvature to the main chain. The polyethylene terephthalate resin has a terephthalic acid unit and an ethylene glycol unit. The content of the isophthalic acid unit is preferably 0.1 mol% or more, more preferably 1.0 mol% or more, based on the total of all repeating units. This is because a thermoplastic resin substrate with excellent stretchability can be obtained. On the other hand, the content of the isophthalic acid unit is preferably 20 mol% or less, more preferably 10 mol% or less, based on the total of all repeating units. Setting this content ratio can satisfactorily increase the crystallinity during the drying shrinkage treatment described below.

[0104] The thermoplastic resin substrate may be stretched by any appropriate method before forming the PVA-based resin layer. For example, the long thermoplastic resin substrate may be stretched in the transverse direction. The transverse direction is preferably a direction approximately perpendicular to the stretching direction of the laminate described below. The stretching temperature of the thermoplastic resin substrate is preferably Tg-10°C to Tg+50°C relative to the glass transition temperature (Tg). The stretching ratio of the thermoplastic resin substrate is preferably 1.5 to 3.0 times.

[0105] As described above, the coating liquid may contain a PVA-based resin and a halide. The coating liquid may typically be a solution in which a PVA-based resin and a halide are dissolved in a solvent. Examples of the solvent include water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, various glycols, polyhydric alcohols such as trimethylolpropane, and amines such as ethylenediamine and diethylenetriamine. Among these, water is preferably used. The concentration of the PVA-based resin is preferably 3 to 20 parts by weight per 100 parts by weight of the solvent. The content of the halide in the coating liquid is preferably 5 to 20 parts by weight, more preferably 10 to 15 parts by weight, per 100 parts by weight of the PVA-based resin.

[0106] Examples of the PVA resin include polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Polyvinyl alcohol can be obtained by saponifying polyvinyl acetate. Ethylene-vinyl alcohol copolymer can be obtained by saponifying ethylene-vinyl acetate copolymer. The saponification degree of the PVA resin is, for example, 85 mol% to 100 mol%, preferably 95.0 mol% to 99.95 mol%, and more preferably 99.0 mol% to 99.93 mol%. The saponification degree can be determined in accordance with JIS K 6726-1994. The average polymerization degree of the PVA resin is, for example, 1000 to 10000, preferably 1200 to 4500, and more preferably 1500 to 4300. The average polymerization degree can be determined in accordance with JIS K 6726-1994. Examples of the halides include iodides such as potassium iodide, sodium iodide, and lithium iodide, and sodium chloride. Of these, potassium iodide is preferably used.

[0107] The coating liquid may contain additives. Examples of additives include plasticizers and surfactants. Examples of plasticizers include polyhydric alcohols such as ethylene glycol and glycerin. Examples of surfactants include nonionic surfactants.

[0108] Stretching a PVA-based resin layer can increase the orientation of polyvinyl alcohol molecules in the PVA-based resin. However, immersing the stretched PVA-based resin layer in a liquid containing water can disrupt the orientation of the polyvinyl alcohol molecules, resulting in a decrease in the orientation. When a laminate of a thermoplastic resin and a PVA-based resin layer is stretched in boric acid water at a relatively high temperature to stabilize the stretching of the thermoplastic resin, the orientation tends to decrease significantly. In contrast, high-temperature stretching (auxiliary stretching) in air of a laminate of a PVA-based resin layer containing a halide and a thermoplastic resin substrate before stretching in boric acid water can promote crystallization of the PVA-based resin in the PVA-based resin layer of the laminate after auxiliary stretching. As a result, when the PVA-based resin layer is immersed in a liquid, the disruption of the orientation of polyvinyl alcohol molecules and the decrease in the orientation can be suppressed compared to when the PVA-based resin layer does not contain a halide. This can improve the optical properties of an absorptive polarizing film obtained by immersing the laminate in a liquid, such as dyeing and underwater stretching.

[0109] To obtain high optical properties, a two-stage stretching method can be selected, combining in-air stretching (auxiliary stretching) and stretching in boric acid water. By introducing auxiliary stretching, stretching can be performed while suppressing crystallization of the thermoplastic resin substrate, thereby solving the problem of reduced stretchability due to excessive crystallization of the thermoplastic resin substrate during subsequent stretching in boric acid water, and allowing the laminate to be stretched at a high magnification. Furthermore, when a PVA-based resin is applied to a thermoplastic resin substrate, the application temperature must be lower than, for example, when the PVA-based resin is applied to a metal drum in order to suppress the influence of the glass transition temperature of the thermoplastic resin substrate. As a result, the crystallization of the PVA-based resin is relatively low, which can lead to problems such as insufficient optical properties being obtained. In contrast, by introducing auxiliary stretching, it is possible to increase the crystallinity of the PVA-based resin, even when the PVA-based resin is applied to a thermoplastic resin, and high optical properties can be achieved. At the same time, by increasing the orientation of the PVA-based resin in advance, problems such as a decrease in orientation or dissolution of the PVA-based resin can be prevented when the resin is immersed in water during subsequent dyeing or stretching processes, and high optical properties can be achieved.

[0110] The method of the auxiliary in-air stretching may be fixed-end stretching (for example, a method of stretching using a tenter stretching machine) or free-end stretching (for example, a method of uniaxially stretching a laminate by passing it between rolls with different peripheral speeds). From the viewpoint of obtaining high optical properties, free-end stretching is preferably used.

[0111] The draw ratio of the auxiliary in-air stretching is preferably 2.0 to 3.5. The auxiliary in-air stretching may be carried out in one stage or in multiple stages. When carried out in multiple stages, the draw ratio is the product of the draw ratios in each stage. The stretching direction in the auxiliary in-air stretching is preferably approximately the same as the stretching direction in the underwater stretching.

[0112] The stretching temperature for the in-air auxiliary stretching is preferably equal to or higher than the glass transition temperature (Tg) of the thermoplastic resin substrate, more preferably equal to or higher than Tg of the thermoplastic resin substrate + 10°C, and even more preferably equal to or higher than Tg of the thermoplastic resin substrate + 15°C. On the other hand, the upper limit of the stretching temperature is preferably 170°C. By stretching at such a temperature, rapid crystallization of the PVA-based resin can be suppressed, thereby preventing defects due to crystallization (for example, preventing the orientation of the PVA-based resin layer due to stretching). The crystallization index of the PVA-based resin after in-air auxiliary stretching is preferably 1.3 to 1.8, more preferably 1.4 to 1.7. The crystallization index of the PVA-based resin can be measured by the ATR method using a Fourier transform infrared spectrophotometer. Specifically, the measurement is performed using polarized light as the measurement light, and the 1141 cm peak of the obtained spectrum is measured. -1 and 1440 cm -1 The crystallization index is calculated using the intensity according to the following formula: Crystallization index=(I C / I R ) where I C is the 1141cm when measuring with incident measuring light. -1 is the intensity of I R is the 1440cm when measuring with incident measurement light. -1 is the strength.

[0113] After the auxiliary air-stretching treatment, an insolubilization treatment may be carried out before the underwater stretching treatment or the dyeing treatment. The insolubilization treatment is typically carried out by immersing the PVA-based resin layer in an aqueous boric acid solution. The insolubilization treatment imparts water resistance to the PVA-based resin layer, and can prevent a decrease in the orientation of PVA when immersed in water. The concentration of the aqueous boric acid solution used in the insolubilization treatment is preferably 1 to 4 parts by weight per 100 parts by weight of water. The liquid temperature of the insolubilization bath (aqueous boric acid solution) is preferably 20 to 50°C.

[0114] The dyeing treatment is typically carried out by dyeing the PVA-based resin layer with iodine. Specifically, the dyeing treatment is carried out by allowing the PVA-based resin layer to adsorb iodine. A preferred method for iodine adsorption is to immerse the PVA-based resin layer (laminate) in a dye solution (dye bath) containing iodine.

[0115] The dye solution is preferably an aqueous iodine solution. In this case, the amount of iodine blended is preferably 0.05 to 0.5 parts by weight per 100 parts by weight of water. In order to increase the solubility of iodine in water, it is preferable to blend an iodide into the aqueous iodine solution. Examples of iodides include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Among these, potassium iodide is preferably used. The amount of iodide blended is preferably 0.1 to 10 parts by weight, more preferably 0.3 to 5 parts by weight, per 100 parts by weight of water. The temperature of the dye solution during dyeing is preferably 20 to 50°C to suppress dissolution of the PVA resin. When the PVA-based resin layer is immersed in the dye solution, the immersion time is preferably 5 seconds to 5 minutes, more preferably 30 seconds to 90 seconds, in order to ensure the transmittance of the PVA-based resin layer.

[0116] The dyeing conditions (concentration, solution temperature, immersion time) can be set so that the single transmittance and polarization degree of the resulting absorptive polarizing film fall within the above-mentioned ranges. For example, the ratio of the iodine content to the potassium iodide content in the iodine aqueous solution used as the dyeing solution is preferably 1:5 to 1:20, more preferably 1:5 to 1:10.

[0117] When a dyeing process is performed consecutively after a treatment (e.g., an insolubilization treatment) in which a laminate is immersed in a treatment bath containing boric acid, the boric acid contained in the treatment bath may be mixed into the dye bath, causing the boric acid concentration of the dye bath to change over time, resulting in unstable dyeability. To prevent this instability in dyeability, the upper limit of the boric acid concentration of the dye bath is preferably adjusted to 4 parts by weight, more preferably 2 parts by weight, per 100 parts by weight of water. Meanwhile, the lower limit of the boric acid concentration of the dye bath is preferably 0.1 parts by weight, more preferably 0.2 parts by weight, and even more preferably 0.5 parts by weight, per 100 parts by weight of water. In one embodiment, a dye bath containing boric acid is used in advance. This can reduce the rate of change in boric acid concentration when the boric acid from the treatment bath is mixed into the dye bath. The amount of boric acid preliminarily added to the dye bath (i.e., the content of boric acid not derived from the treatment bath) is preferably 0.1 to 2 parts by weight, and more preferably 0.5 to 1.5 parts by weight, per 100 parts by weight of water.

[0118] A crosslinking treatment may be carried out after the dyeing treatment and before the underwater stretching treatment. The crosslinking treatment is typically carried out by immersing the PVA-based resin layer in an aqueous boric acid solution. The crosslinking treatment imparts water resistance to the PVA-based resin layer, thereby preventing a decrease in the orientation of the PVA when the layer is immersed in high-temperature water during the subsequent underwater stretching treatment. The concentration of the aqueous boric acid solution used in the crosslinking treatment is preferably 1 to 5 parts by weight per 100 parts by weight of water. Furthermore, when the crosslinking treatment is carried out after the dyeing treatment, it is preferable to further incorporate an iodide. The incorporation of an iodide can suppress the elution of iodine adsorbed to the PVA-based resin layer. The amount of iodide incorporated is preferably 1 to 5 parts by weight per 100 parts by weight of water. Specific examples of iodides are as described above. The liquid temperature of the crosslinking bath (aqueous boric acid solution) is preferably 20 to 50°C.

[0119] The underwater stretching treatment is carried out by immersing the laminate in a stretching bath. Underwater stretching treatment allows stretching at a temperature lower than the glass transition temperature (typically about 80°C) of the thermoplastic resin substrate and the PVA-based resin layer, and the PVA-based resin layer can be stretched while suppressing crystallization. As a result, a polarizing film with excellent optical properties can be produced.

[0120] Any appropriate method can be adopted as the method for stretching the laminate. Specifically, it may be fixed-end stretching or free-end stretching (for example, a method in which the laminate is uniaxially stretched by passing it between rolls with different peripheral speeds). Free-end stretching is preferably selected. The stretching of the laminate may be carried out in one stage or in multiple stages. When it is carried out in multiple stages, the stretch ratio of the laminate described below is the product of the stretch ratios in each stage.

[0121] The underwater stretching is preferably performed by immersing the laminate in an aqueous boric acid solution (stretching in boric acid solution). Using an aqueous boric acid solution as the stretching bath can impart to the PVA-based resin layer rigidity sufficient to withstand the tension applied during stretching and water resistance sufficient to prevent dissolution in water. Specifically, boric acid generates tetrahydroxyborate anions in the aqueous solution, which can crosslink with the PVA-based resin through hydrogen bonding. As a result, the PVA-based resin layer is imparted with rigidity and water resistance, allowing it to be stretched satisfactorily, resulting in the production of an absorptive polarizing film with excellent optical properties.

[0122] The boric acid aqueous solution is preferably obtained by dissolving boric acid and / or a borate in water as a solvent. The boric acid concentration is preferably 1 to 10 parts by weight, more preferably 2.5 to 7 parts by weight, and even more preferably 3 to 6 parts by weight, per 100 parts by weight of water. By adjusting the boric acid concentration to 1 part by weight or more, dissolution of the PVA-based resin layer can be effectively suppressed, allowing for the production of an absorptive polarizing film with better properties. In addition to boric acid or a borate, aqueous solutions obtained by dissolving boron compounds such as borax, glyoxal, glutaraldehyde, etc. in a solvent can also be used.

[0123] Preferably, an iodide is added to the stretching bath (boric acid aqueous solution). By adding an iodide, it is possible to suppress the elution of iodine adsorbed in the PVA resin layer. Specific examples of iodides are as described above. The concentration of the iodide is preferably 0.05 to 15 parts by weight, more preferably 0.5 to 8 parts by weight, per 100 parts by weight of water.

[0124] The stretching temperature (liquid temperature of the stretching bath) is preferably 40°C or higher, more preferably 60°C or higher. At such a temperature, good stretching can be achieved. Specifically, as described above, the glass transition temperature (Tg) of the thermoplastic resin substrate is preferably 60°C or higher in relation to the formation of the PVA-based resin layer. In this case, if the stretching temperature is lower than 40°C, good stretching may not be possible, even taking into account the plasticization of the thermoplastic resin substrate by water. On the other hand, the stretching temperature (liquid temperature of the stretching bath) is preferably 85°C or lower, more preferably 75°C or lower. The higher the temperature of the stretching bath, the higher the solubility of the PVA-based resin layer, which may result in poor optical properties. The immersion time of the laminate in the stretching bath is preferably 15 seconds to 5 minutes.

[0125] In one embodiment, the stretching ratio in underwater stretching is preferably 1.0 to 2.2, more preferably 1.1 to 2.0, even more preferably 1.1 to 1.8, and particularly preferably 1.2 to 1.6. By setting the stretching ratio in underwater stretching within this range, an absorptive polarizing film that can achieve the durability described below can be obtained without combining a protective layer. Furthermore, a polarizing film in which breakage along the absorption axis direction is suppressed can be obtained. The total stretching ratio of the laminate is preferably 3.0 to 4.5, more preferably 3.0 to 4.3, and even more preferably 3.0 to 4.0, times the original length of the laminate.

[0126] In one embodiment, the stretching ratio in underwater stretching is preferably 1.5 times or more, more preferably 3.0 times or more. The total stretching ratio of the laminate is preferably 5.0 times or more, and even more preferably 5.5 times or more, relative to the original length of the laminate. By achieving such a high stretching ratio, an absorptive polarizing film with excellent optical properties can be produced. Such a high stretching ratio can be achieved by employing underwater stretching (stretching in boric acid water).

[0127] The drying shrinkage treatment may be performed by zone heating, which heats the entire zone, or by heating the transport rolls (using so-called heated rolls). Preferably, both methods are used. Drying using heated rolls efficiently suppresses heat curling of the laminate, resulting in the production of an absorptive polarizing film with excellent appearance. Specifically, drying the laminate while it is aligned with heated rolls efficiently promotes crystallization of the thermoplastic resin substrate, thereby increasing the crystallinity. Even at relatively low drying temperatures, the crystallinity of the thermoplastic resin substrate can be favorably increased. As a result, the rigidity of the thermoplastic resin substrate increases, enabling it to withstand shrinkage of the PVA-based resin layer due to drying, thereby suppressing curling. Furthermore, using heated rolls allows the laminate to be dried while maintaining a flat state, thereby suppressing not only curling but also wrinkling. At this time, the optical properties of the laminate can be improved by shrinking it in the width direction through the drying shrinkage treatment. This is because the orientation of the PVA and the PVA / iodine complex can be effectively enhanced. The shrinkage rate of the laminate in the width direction due to the drying shrinkage treatment is preferably 1% to 10%, more preferably 2% to 8%, and particularly preferably 4% to 6%. By using a heated roll, the laminate can be continuously shrunk in the width direction while being transported, thereby achieving high productivity.

[0128] For example, drying conditions can be controlled by adjusting the heating temperature of the transport rolls (heating roll temperature), the number of heating rolls, the contact time with the heating rolls, etc. The temperature of the heating rolls is preferably 60°C to 120°C, more preferably 65°C to 100°C, and even more preferably 70°C to 80°C. This effectively increases the crystallinity of the thermoplastic resin, effectively suppressing curling and imparting excellent strength to the laminate. The temperature of the heating rolls can be measured with a contact thermometer. Typically, 2 to 40 transport rolls, preferably 4 to 30 rolls, are used. The contact time between the laminate and the heating rolls (total contact time) is preferably 1 to 300 seconds, more preferably 1 to 20 seconds, and even more preferably 1 to 10 seconds.

[0129] The heating rolls may be installed in a heating furnace (e.g., an oven) or in a normal production line (under room temperature). Preferably, they are installed in a heating furnace equipped with a blower. By using both heating roll drying and hot air drying, it is possible to suppress abrupt temperature changes between the heating rolls, and to easily control shrinkage in the width direction. The hot air drying temperature is preferably 30°C to 100°C. The hot air drying time is preferably 1 second to 300 seconds. The hot air speed is preferably about 10 m / s to 30 m / s. Note that this air speed is the air speed inside the heating furnace and can be measured with a mini-vane type digital anemometer.

[0130] Preferably, after the underwater stretching treatment and before the drying shrinkage treatment, a washing treatment is carried out by, for example, immersing the PVA-based resin layer in an aqueous potassium iodide solution.

[0131] By subjecting the PVA-based resin layer to various treatments, an absorptive polarizing film can be obtained. The PVA-based resin layer of the thermoplastic resin substrate can also be subjected to various treatments. The tensile modulus of the thermoplastic resin substrate after the various treatments is, for example, 1.0 × 10 9 Pa or more 1.0×10 10 The haze of the thermoplastic resin substrate after various treatments is, for example, 2% or less.

[0132] The protective member typically includes a substrate. The substrate can be made of any appropriate film. Examples of materials that form the main component of the film constituting the substrate include cellulose-based resins such as triacetyl cellulose (TAC), polyester-based, polyvinyl alcohol-based, polycarbonate-based, polyamide-based, polyimide-based, polyethersulfone-based, polysulfone-based, polystyrene-based, cycloolefin-based resins such as polynorbornene, polyolefin-based, (meth)acrylic, and acetate-based resins. Here, (meth)acrylic refers to acrylic and / or methacrylic. The thickness of the substrate is preferably 5 μm to 80 μm, more preferably 10 μm to 50 μm, and even more preferably 15 μm to 40 μm.

[0133] The protective member is preferably composed of a laminated film having a substrate and a surface treatment layer formed on the substrate. The thickness of the laminated film is preferably 10 μm to 80 μm, more preferably 15 μm to 60 μm, and even more preferably 20 μm to 45 μm. The thickness of the surface treatment layer is preferably 0.5 μm to 10 μm, more preferably 1 μm to 7 μm, and even more preferably 2 μm to 5 μm.

[0134] The surface treatment layer typically includes a hard coat layer. The hard coat layer is typically formed by applying a hard coat layer-forming material to a substrate and curing the applied layer. The hard coat layer-forming material typically includes a curable compound as a layer-forming component. Examples of the curing mechanism of the curable compound include heat curing and photocuring. Examples of the curable compound include monomers, oligomers, and prepolymers. Preferably, a polyfunctional monomer or oligomer is used as the curable compound. Examples of the polyfunctional monomer or oligomer include a monomer or oligomer having two or more (meth)acryloyl groups, a urethane (meth)acrylate or a urethane (meth)acrylate oligomer, an epoxy-based monomer or oligomer, and a silicone-based monomer or oligomer.

[0135] The thickness of the hard coat layer is preferably 0.5 μm to 10 μm, more preferably 1 μm to 7 μm, and even more preferably 2 μm to 5 μm.

[0136] The surface treatment layer preferably includes a functional layer. The functional layer preferably functions as an antireflection layer. In a preferred embodiment, the surface treatment layer includes, from the substrate side, the hard coat layer and the antireflection layer in this order. The thickness of the functional layer is preferably 0.05 μm to 10 μm, more preferably 0.1 μm to 5 μm, and even more preferably 0.1 μm to 2 μm.

[0137] The surface protection film is typically a laminate of a base film and a pressure-sensitive adhesive layer. Materials for forming the base film include polyester-based polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); cellulose-based polymers such as diacetyl cellulose and triacetyl cellulose; polycarbonate-based polymers; (meth)acrylic polymers such as polymethyl methacrylate; and cycloolefin-based polymers such as polynorbornene. These may be used alone or in combination of two or more. The thickness of the base film is preferably 15 μm to 70 μm, more preferably 20 μm to 60 μm, and even more preferably 25 μm to 50 μm. The thickness of the pressure-sensitive adhesive layer is, for example, 5 μm to 15 μm. Furthermore, the self-adhesive film may be used as the surface protection film.

[0138] The release liner may typically be made of any suitable plastic film. Specific examples of plastic films include polyethylene terephthalate (PET) film, polyethylene film, and polypropylene film. A plastic film whose surface is coated with a release agent is preferably used as the release liner. Examples of the release agent include silicone-based release agents, fluorine-based release agents, and long-chain alkyl acrylate-based release agents.

[0139] The thickness of the release liner is preferably 30 μm or more, more preferably 40 μm or more, and even more preferably 50 μm or more, and is, for example, 100 μm or less.

[0140] As shown in the figure, each member included in the optical laminate 1 can be integrated via an adhesive layer (for example, a pressure-sensitive adhesive layer). The optical laminate 1 may also be provided integrally with the second lens portion of the display system via an adhesive layer (for example, a pressure-sensitive adhesive layer). The adhesive layer may be formed of an adhesive or a pressure-sensitive adhesive. The thickness of the adhesive layer is, for example, 0.05 μm to 30 μm, preferably 0.5 μm to 20 μm, and more preferably 3 μm to 15 μm.

[0141] The pressure-sensitive adhesive layer can be composed of any appropriate pressure-sensitive adhesive. Specific examples include acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, silicone pressure-sensitive adhesives, polyester pressure-sensitive adhesives, urethane pressure-sensitive adhesives, epoxy pressure-sensitive adhesives, and polyether pressure-sensitive adhesives. By adjusting the type, number, combination, and compounding ratio of monomers forming the base resin of the pressure-sensitive adhesive, as well as the compounding amount of cross-linking agent, reaction temperature, reaction time, etc., a pressure-sensitive adhesive having desired properties according to the purpose can be prepared. The base resin of the pressure-sensitive adhesive may be used alone or in combination of two or more types. An acrylic resin is preferably used as the base resin. Specifically, the pressure-sensitive adhesive layer is preferably composed of an acrylic pressure-sensitive adhesive.

[0142] For example, the pressure-sensitive adhesive layer can be formed by coating and drying a pressure-sensitive adhesive composition containing a base resin, additives such as a crosslinking agent, and a solvent. The pressure-sensitive adhesive composition may be directly coated onto the adherend, or may be coated onto a substrate such as a separately prepared base film (e.g., a release liner). Drying is typically performed by heating. From the viewpoint of forming a good pressure-sensitive adhesive layer, the tensile modulus of the base film onto which the pressure-sensitive adhesive composition is coated is preferably 1.0 × 10 9 Pa or more. [Example]

[0143] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The thickness, retardation value, haze, tensile modulus, surface roughness Ra, and peel force are values ​​measured by the following measurement methods. Unless otherwise specified, "parts" and "%" are based on weight. <Thickness> Thicknesses of 10 μm or less were measured using a scanning electron microscope (manufactured by JEOL Ltd., product name "JSM-7100F"), and thicknesses of more than 10 μm were measured using a digital micrometer (manufactured by Anritsu Corporation, product name "KC-351C"). <Phase difference value> The phase difference value at each wavelength at 23°C was measured using a Mueller matrix polarimeter (manufactured by Axometrics, product name "Axoscan"). <Haze> The haze was measured in accordance with JIS 7136 using a haze meter (manufactured by Murakami Color Science Laboratory, product name "HN-150"). <Tensile modulus> The specimens to be measured were formed into tensile test dumbbells with a parallel section width of 10 mm and a length of 40 mm in accordance with JIS K 6734:2000, which were then pulled in the longitudinal direction at a pulling rate of 300 mm / min using a tensile tester (Shimadzu Corporation, "Autograph AG-Xplus"), and the tensile modulus was calculated from the slope of the line in the resulting stress-strain curve for test forces of 10 N to 20 N. The measurements were carried out in an environment of 23°C and a relative humidity of 50% RH. <Surface roughness Ra> Surface roughness Ra was measured using a scanning white light interferometer (Zygo, product name "NewView9000"). Specifically, the sample was placed on a vibration-isolated measurement table, interference fringes were generated using a single white LED light, and an interference objective lens (10x magnification) with a reference plane was scanned in the Z direction (thickness direction) to selectively obtain the surface roughness Ra of the outermost surface of the sample. When the sample was a film, the film was statically laminated to a microslide glass (Matsunami Glass Industry, product name "S200200") to prevent the inclusion of foreign matter, bubbles, or deformation lines, and the surface roughness Ra was measured in accordance with JIS B 0601. <Peeling force> A sample measuring 25 mm wide and 50 mm long was cut from the object to be measured and left for at least 30 minutes in an environment of 23°C and 50% RH relative humidity, after which the peel force (N / 50 mm) was measured using a universal tensile tester when peeled in the longitudinal direction at a peel speed of 300 mm / min and a peel angle of 180°. The measurements were carried out in an environment of 23°C and 50% RH relative humidity.

[0144] [Example 1] (Fabrication of an absorption polarizing film) A primer composition was prepared according to U.S. Patent Application Publication No. 2020 / 0110209. The resulting primer composition was applied to a 60 μm thick film having a tensile modulus of 3.5×10 using a wire bar. 9 The solution was applied to a TAC film (Konica Minolta, "KC2UA") with a haze of 0.9% at 100 Pa, and the coated film was dried at 60°C for 3 minutes to form a primer layer with a thickness of 30 nm. Next, a lyotropic liquid crystalline polymer consisting of the structural unit of formula (1) was dissolved in water to a solids concentration of 14% by mass. A birefringent aromatic polymer (Structure P1) was prepared as the lyotropic liquid crystalline polymer according to Example 17 of U.S. Patent Application Publication No. 2020 / 0110209. The lyotropic liquid crystalline polymer contained a sodium sulfonate base group. The resulting liquid crystalline polymer aqueous solution was applied to the primer layer using a wire bar and dried at 60°C for 3 minutes to form a 3 μm-thick lyotropic liquid crystalline layer. This material exhibited a retardation with a slow axis in the coating direction due to molecular orientation caused by shear stress during application. Next, the organic dyes represented by the above formulas (24) to (26) were prepared in accordance with U.S. Patent Application Publication No. 2020 / 0110209. Thereafter, the organic dyes represented by the above formulas (24) to (26) were dissolved in water in a mass ratio of formula (24):formula (25):formula (26) = 18:7:8 to prepare a dyeing solution with a solids concentration of 1.9 mass%. The lyotropic liquid crystal layer was then dyed by immersion in the dye solution for 90 seconds, and then insolubilized by immersion in a 10% by mass SrCl2 aqueous solution for 3 seconds. The lyotropic liquid crystal layer was then washed by immersion in pure water for 3 seconds, and then air-dried by blowing off excess water with compressed air. In this way, an absorptive polarizing film having a thickness of 3 μm was formed on the TAC film.

[0145] (Preparation of the first laminate) The surface of the absorptive polarizing film formed on the TAC film was coated with a 30 μm thick film with a tensile modulus of 3.0 × 10 8 A protective film (self-adhesive polyethylene film, manufactured by Toray Advanced Film Co., Ltd., "Tretec (registered trademark) 7832C") with a haze of 7% was attached at 100 Pa to prepare a first laminate. Then, a punching blade was used to obtain a first laminate having a rectangular shape in plan view, with long sides of 350 mm and short sides of 250 mm. No scratches caused by the punching blade were observed on the punched first laminate. Furthermore, since the first laminate did not have an adhesive layer, no adhesive stains were observed.

[0146] (Fabrication of λ / 4 components) Polymerization was carried out using a batch polymerization apparatus consisting of two vertical reactors equipped with stirring blades and reflux condensers controlled at 100° C. The polymerization mixture contained 29.60 parts by mass (0.046 mol) of bis[9-(2-phenoxycarbonylethyl)fluoren-9-yl]methane, 29.21 parts by mass (0.200 mol) of isosorbide (ISB), 42.28 parts by mass (0.139 mol) of spiroglycol (SPG), 63.77 parts by mass (0.298 mol) of diphenyl carbonate (DPC), and 1.19 × 10 calcium acetate monohydrate as a catalyst. -2 Part of mass (6.78×10 -5 (mol) was charged. After purging the reactor with nitrogen under reduced pressure, heating was performed using a heat transfer medium. Stirring was initiated when the internal temperature reached 100°C. Forty minutes after the start of the temperature increase, the internal temperature reached 220°C. This temperature was maintained while simultaneously reducing the pressure. 90 minutes after reaching 220°C, the pressure was reduced to 13.3 kPa. Phenol vapor by-produced during the polymerization reaction was introduced into a reflux condenser at 100°C, and the small amount of monomer components contained in the phenol vapor was returned to the reactor. Uncondensed phenol vapor was collected by introducing nitrogen into the first reactor and temporarily restoring the pressure to atmospheric pressure. The oligomerized reaction liquid in the first reactor was then transferred to the second reactor. Next, heating and depressurization of the second reactor were initiated, and the internal temperature reached 240°C and the pressure reached 0.2 kPa in 50 minutes. The polymerization was then allowed to proceed until the specified stirring power was reached. When the predetermined power was reached, nitrogen was introduced into the reactor to restore pressure, and the polyester carbonate resin produced was extruded into water, and the strands were cut to obtain pellets.

[0147] The resulting polyester carbonate resin pellets were vacuum-dried at 80°C for 5 hours and then used in a film-making machine equipped with a single-screw extruder (manufactured by Toshiba Machine Co., Ltd., cylinder temperature setting: 250°C), a T-die (width: 200 mm, temperature setting: 250°C), a chill roll (temperature setting: 120-130°C), and a winder to produce a 135 μm-thick long resin film. The resulting long resin film was stretched in the width direction at a stretching temperature of 143°C and a stretch ratio of 2.8 to obtain a 48 μm-thick stretched film. The resulting stretched film had an Re(550) of 143 nm, an Re(450) / Re(550) of 0.86, and an Nz coefficient of 1.12.

[0148] (Preparation of second laminate) A 5 μm-thick adhesive layer 1 was laminated on one side of the obtained λ / 4 member. A release liner 1 (a polyethylene terephthalate film treated with a silicone-based release agent, 38 μm thick, manufactured by Toray Advanced Film Co., Ltd., "#38 K Therapeel MDA") was attached to the surface of this adhesive layer 1. Next, a 15 μm thick adhesive layer 2 was laminated on the other side of the λ / 4 member. A release liner 2 (a polyethylene terephthalate film (thickness 50 μm, manufactured by Mitsubishi Chemical Corporation, "Diafoil MHE50") treated with a silicone-based release agent) was attached to the surface of this adhesive layer 2. In this way, a second laminate was obtained. Thereafter, a punching die was used to obtain a second laminate having a rectangular shape in plan view with long sides of 350 mm and short sides of 250 mm.

[0149] (Preparation of Optical Laminate 1) The release liner 1 was peeled off from the second laminate punched into a rectangular shape to expose the pressure-sensitive adhesive layer 1. The protective film was peeled off from the first laminate punched into a rectangular shape, and the absorptive polarizing film of the first laminate was attached to the pressure-sensitive adhesive layer 1 of the second laminate to produce an optical laminate 1. At this time, the attachment was performed so that the absorption axis of the absorptive polarizing film of the first laminate and the slow axis of the λ / 4 component of the second laminate formed an angle of 45°. The attachment was performed so that the corners of the first laminate and the second laminate were aligned.

[0150] When peeling the protective film from the first laminate, no peeling failure occurred. The production of optical laminate 1 was performed 30 times, and the incidence of peeling failure was 0%. The peeling force of the protective film from the absorptive polarizing film was less than 0.01 N / 50 mm. In addition, when peeling off the protective film, it appears cloudy and white, making it easy to distinguish between the base material (TAC film) and the protective film (distinguishing between the front and back), making it easy to work with.

[0151] [Example 2] (Preparation of the first laminate) A first laminate was obtained in the same manner as in Example 1, except that a polarizing film prepared as described below was used as the absorptive polarizing film, and accordingly, a polyethylene terephthalate film was used as the substrate instead of a TAC film. Thereafter, a first laminate having a rectangular shape in plan view with long sides of 350 mm and short sides of 250 mm was obtained using a punching blade, as in Example 1. No scratches caused by the punching blade were observed on the punched first laminate. Furthermore, since the first laminate did not have an adhesive layer, no adhesive stains were observed.

[0152] (Fabrication of an absorption polarizing film) The thermoplastic resin substrate was a long, amorphous isophthalic copolymerized polyethylene terephthalate film (thickness: 100 μm) with a water absorption rate of 0.75% and a Tg of approximately 75° C. One side of the resin substrate was subjected to a corona treatment. A PVA aqueous solution (coating liquid) was prepared by dissolving 100 parts by weight of a PVA-based resin made by mixing polyvinyl alcohol (polymerization degree 4200, saponification degree 99.2 mol%) and acetoacetyl-modified PVA (manufactured by Mitsubishi Chemical Corporation, trade name "Gohsenex Z410") in a 9:1 ratio, to which 13 parts by weight of potassium iodide was added, in water. The above PVA aqueous solution was applied to the corona treated surface of the resin substrate and dried at 60° C. to form a PVA resin layer with a thickness of 13 μm, thereby producing a laminate. The resulting laminate was uniaxially stretched at its free end to 2.4 times its original size in the machine direction (longitudinal direction) between rolls with different peripheral speeds in an oven at 130°C (auxiliary in-air stretching treatment). Next, the laminate was immersed in an insolubilizing bath (a boric acid aqueous solution obtained by mixing 4 parts by weight of boric acid with 100 parts by weight of water) at a liquid temperature of 40°C for 30 seconds (insolubilizing treatment). Next, the film was immersed in a dye bath (an aqueous iodine solution obtained by mixing iodine and potassium iodide in a weight ratio of 1:7 with 100 parts by weight of water) at a liquid temperature of 30°C for 60 seconds while adjusting the concentration so that the single transmittance (Ts) of the final polarizing film would be 42.0% or higher (dyeing treatment). Next, the sample was immersed in a crosslinking bath (a boric acid aqueous solution obtained by blending 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with 100 parts by weight of water) at a liquid temperature of 40°C for 30 seconds (crosslinking treatment). The laminate was then immersed in an aqueous boric acid solution (boric acid concentration 4 wt %, potassium iodide concentration 5 wt %) at a liquid temperature of 62°C and uniaxially stretched in the longitudinal direction (longitudinal direction) between rolls with different peripheral speeds to a total stretch ratio of 5.5 times (underwater stretching treatment). Thereafter, the laminate was immersed in a cleaning bath (aqueous solution obtained by mixing 4 parts by weight of potassium iodide with 100 parts by weight of water) at a liquid temperature of 20° C. (cleaning treatment). Thereafter, while drying in an oven maintained at 90°C, the laminate was brought into contact with a SUS heated roll whose surface temperature was maintained at 75°C for approximately 2 seconds (drying shrinkage treatment). The shrinkage rate in the width direction of the laminate due to the drying shrinkage treatment was 5.2%. In this way, the thickness was 38 μm and the tensile modulus was 2.0 × 10 9 A polarizing film (absorption type polarizing film) having a thickness of 5 μm was formed on the resin substrate of PA.

[0153] (Preparation of Optical Laminate 1) An optical laminate 1 was obtained in the same manner as in Example 1, except that the above-described first laminate was used. When the protective film was peeled from the first laminate, no peeling failure occurred. As in Example 1, the production of optical laminate 1 was performed 30 times, but the incidence of peeling failure was 0%. The peeling force of the protective film from the absorptive polarizing film was less than 0.01 N / 50 mm. In addition, when peeling off the protective film, it appears cloudy and white, making it easy to distinguish between the base material (polyethylene terephthalate film) and the protective film (distinguishing between the front and back), making it easy to work with.

[0154] [Comparative Example 1] (Preparation of the first laminate) In the same manner as in Example 1, an absorptive polarizing film was formed on a TAC film, and a 5 μm-thick adhesive layer 1 was laminated on the surface of the absorptive polarizing film. A release liner 3 (a polyethylene terephthalate film treated with a silicone-based release agent, 38 μm in thickness, with a tensile modulus of 2.0×10) was laminated on the surface of this adhesive layer 1. 9 Pa, manufactured by Mitsubishi Chemical Polyester Film Co., Ltd., "MRF38") was bonded to the laminate. In this way, a first laminate was produced. Thereafter, a punching blade was used to obtain a first laminate having a rectangular shape in plan view, with long sides of 350 mm and short sides of 250 mm. No scratches caused by the punching blade were observed on the punched first laminate. However, glue stains from the pressure-sensitive adhesive layer 1 were observed on the edges. It is thought that glue stains can occur significantly when the thickness of the absorptive polarizing film is thin (for example, 7 μm or less).

[0155] (Preparation of second laminate) A self-adhesive polyethylene film (manufactured by Toray Advanced Film Co., Ltd., "Tretec (registered trademark) 7832C") was attached as a surface protection film to one side of the λ / 4 member obtained in the same manner as in Example 1. Next, a 15 μm thick adhesive layer 2 was laminated on the other side of the λ / 4 member. A release liner 2 (a polyethylene terephthalate film (thickness 50 μm, manufactured by Mitsubishi Chemical Corporation, "Diafoil MHE50") treated with a silicone-based release agent) was attached to the surface of this adhesive layer 2. In this way, a second laminate was obtained. Thereafter, a punching die was used to obtain a second laminate having a rectangular shape in plan view with long sides of 350 mm and short sides of 250 mm.

[0156] (Preparation of Optical Laminate 1) The release liner 3 was peeled off from the first laminate punched into a rectangular shape to expose the pressure-sensitive adhesive layer 1. The surface protection film was peeled off from the second laminate punched into a rectangular shape, and the λ / 4 member of the second laminate was attached to the pressure-sensitive adhesive layer 1 of the first laminate, thereby attempting to produce an optical laminate 1.

[0157] When the release liner 3 was peeled off from the first laminate punched into a rectangular shape to expose the pressure-sensitive adhesive layer 1, peeling failure occurred. Specifically, when the release liner 3 was peeled off from the first laminate having a very thin absorptive polarizing film, peeling occurred between the TAC film and the absorptive polarizing film. Thirty attempts were made to produce the optical laminate 1, and the incidence of peeling failure was 100%. The peel strength of the release liner 3 from the pressure-sensitive adhesive layer 1 was 0.07 N / 50 mm to 0.15 N / 50 mm.

[0158] Comparative Example 2 (Preparation of the first laminate) The protective film was a PET film (total thickness 48 μm, tensile modulus 2.0 × 10) with a 10 μm thick adhesive layer. 9 A first laminate was obtained in the same manner as in Example 1, except that a mask having a thickness of 100 Pa and a haze of 3.0%, "E-MASK RP109F" manufactured by Nitto Denko Corporation, was used. Thereafter, a first laminate having a rectangular shape in plan view with a long side of 350 mm and a short side of 250 mm was obtained using a punching blade, as in Example 1. No scratches caused by the punching blade were observed on the punched first laminate. Furthermore, no adhesive stains caused by the adhesive were observed on the punched first laminate.

[0159] (Preparation of Optical Laminate 1) An attempt was made to prepare an optical laminate 1 in the same manner as in Example 1, except that the above-described first laminate was used. However, when peeling the protective film from the first laminate, peeling failure occurred. Specifically, when peeling the protective film from the absorptive polarizing film, peeling occurred between the TAC film and the absorptive polarizing film. Thirty attempts were made to prepare an optical laminate 1, but the incidence of peeling failure was 90%. The peeling force of the protective film from the absorptive polarizing film was 0.01 N / 50 mm.

[0160] In Comparative Examples 1 and 2, poor peeling of the release liner or protective film occurred when laminating the absorptive polarizing film and the λ / 4 member, and it was almost impossible to proceed to the next step. On the other hand, in Examples 1 and 2, no peeling problems occurred with the protective film when laminating the absorptive polarizing film and the λ / 4 member, and the product could proceed to the next step. Specifically, the substrate (TAC film or polyethylene terephthalate film) was peeled from the absorptive polarizing film of optical laminate 1. The peel strength of the substrate from the absorptive polarizing film was less than 0.01 N / 50 mm in both Examples 1 and 2. Thereafter, a reflective polarizing film ("APCF" manufactured by Nitto Denko Corporation) was bonded to the absorptive polarizing film via a 10 μm-thick adhesive layer. Next, a protective member prepared as described below was bonded via a 12 μm-thick adhesive layer to obtain an optical laminate.

[0161] (Production of protective material) The hard coat layer-forming material described below was applied to an acrylic film (thickness: 40 μm) having a lactone ring structure and heated at 90°C for 1 minute. After heating, the applied layer was irradiated with a high-pressure mercury lamp at an integrated light intensity of 300 mJ / cm. 2 The coating layer was cured by irradiation with ultraviolet light of 1000 kJ / cm, thereby producing an acrylic film (thickness: 44 μm) on which a hard coat layer having a thickness of 4 μm was formed. Next, the following coating solution A for forming an antireflection layer was applied onto the hard coat layer using a wire bar, and the applied coating solution was heated at 80°C for 1 minute and dried to form a coating film. The dried coating film was then irradiated with a high-pressure mercury lamp at an integrated light intensity of 300 mJ / cm. 2 The coating was cured by irradiating it with ultraviolet light of 1000 kJ / cm 2 , thereby forming an antireflection layer A having a thickness of 140 nm. Next, the following coating solution B for forming an antireflection layer was applied onto the antireflection layer A using a wire bar, and the applied coating solution was heated at 80°C for 1 minute and dried to form a coating film. The dried coating film was irradiated with an integrated light dose of 300 mJ / cm using a high-pressure mercury lamp. 2 The coating was cured by irradiating it with ultraviolet light of 1000 kJ / cm 2 , thereby forming an antireflection layer B having a thickness of 105 nm. In this way, a protective member (thickness: 44 μm) was obtained.

[0162] (Hard Coat Layer Forming Material) A hard coat layer-forming material was prepared by mixing 50 parts of a urethane acrylic oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd., "NK Oligo UA-53H"), 30 parts of a multifunctional acrylate whose main component is pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Ltd., trade name "Viscoat #300"), 20 parts of 4-hydroxybutyl acrylate (manufactured by Osaka Organic Chemical Industry Ltd.), 1 part of a leveling agent (manufactured by DIC Corporation, "GRANDIC PC4100"), and 3 parts of a photopolymerization initiator (manufactured by Ciba Japan, "Irgacure 907") and diluting with methyl isobutyl ketone to a solids concentration of 50%.

[0163] (Anti-reflection layer forming coating solution A) 100 parts by weight of a multifunctional acrylate (manufactured by Arakawa Chemical Industries, Ltd., trade name "Opstar KZ6728", solid content 20% by weight), 3 parts by weight of a leveling agent (manufactured by DIC Corporation, "GRANDIC PC4100"), and 3 parts by weight of a photopolymerization initiator (manufactured by BASF, trade name "OMNIRAD907", solid content 100% by weight) were mixed. The mixture was diluted with butyl acetate as a dilution solvent to a solid content of 12% by weight, and the mixture was stirred to prepare Coating Solution A for forming an antireflection layer.

[0164] (Anti-reflection layer forming coating solution B) 100 parts by weight of a polyfunctional acrylate containing pentaerythritol triacrylate as the main component (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name "Viscoat #300", solid content 100 wt%), 150 parts by weight of hollow nanosilica particles (manufactured by JGC Catalysts and Chemicals Industries, Ltd., trade name "Sururia 5320", solid content 20 wt%, weight average particle diameter 75 nm), 50 parts by weight of solid nanosilica particles (manufactured by Nissan Chemical Industries, Ltd., trade name "MEK-2140Z-AC", solid content 30 wt%, weight average particle diameter 10 nm), 12 parts by weight of a fluorine-containing additive (manufactured by Shin-Etsu Chemical Co., Ltd., trade name "KY-1203", solid content 20 wt%), and 3 parts by weight of a photopolymerization initiator (manufactured by BASF, trade name "OMNIRAD907", solid content 100 wt%) were mixed. To this mixture, a mixed solvent of TBA (tertiary butyl alcohol), MIBK (methyl isobutyl ketone), and PMA (propylene glycol monomethyl ether acetate) in a weight ratio of 60:25:15 was added as a dilution solvent to make the total solid content 4% by weight, and the mixture was stirred to prepare coating solution B for forming an anti-reflection layer.

[0165] The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the configurations shown in the above-described embodiment can be replaced with configurations that are substantially the same as those shown in the above-described embodiment, that have the same effects, or that can achieve the same purpose. [Industrial Applicability]

[0166] The optical laminate according to the embodiment of the present invention can be used for a display such as VR goggles, for example. [Explanation of symbols]

[0167] 1 Optical laminate, 10 Display system, 12 Display element, 14 Reflective polarizing element, 16 First lens portion, 18 Half mirror, 20 First λ / 4 element, 22 Second λ / 4 element, 24 Second lens portion, 26 User's eye, 28 Absorptive polarizing element, 30 Third λ / 4 element, 31 Protective element, 41 First adhesive layer, 42 Second adhesive layer, 43 Adhesive layer, 44 Adhesive layer, 51 Surface protective film, 52 Release liner, 53 Substrate, 54 Protective film, 100 First laminate, 200 Second laminate.

Claims

1. preparing a first laminate having a substrate, an absorptive polarizing film formed on the substrate, and a protective film attached to the absorptive polarizing film; cutting the first laminate into a predetermined shape to obtain a sheet-like first laminate; Preparing a sheet-like second laminate having a phase difference member having a first main surface and a second main surface facing each other and a first pressure-sensitive adhesive layer disposed on the first main surface side of the phase difference member; and peeling the protective film from the sheet-like first laminate, and bonding the absorptive polarizing film of the sheet-like first laminate to the first pressure-sensitive adhesive layer of the sheet-like second laminate, the thickness of the absorptive polarizing film is 7 μm or less, the protective film has a tensile modulus smaller than the tensile modulus of the base material; the protective film has a tensile modulus of elasticity of 1.0×10 8 Pa or more and less than 1.0×10 9 Pa and a thickness of 10 μm to 150 μm; the substrate has a tensile modulus of elasticity of 1.0×10 9 Pa or more; the peeling force of the protective film from the absorptive polarizing film is less than 0.01 N / 50 mm; the peeling force of the substrate to the absorptive polarizing film is 0.01 N / 50 mm to 0.06 N / 50 mm; A method for producing an optical laminate.

2. The manufacturing method according to claim 1 , wherein the protective film is a self-adhesive film.

3. The method according to claim 1 , wherein the haze of the protective film is 3% or more.

4. The method for producing a polarizing film according to claim 1 , further comprising the steps of: laminating the absorptive polarizing film to the first pressure-sensitive adhesive layer; and then peeling the substrate from the absorptive polarizing film.

5. The manufacturing method according to claim 1 , wherein the second laminate in the form of a single sheet has the same shape in a plan view as the first laminate after the cutting.

6. The manufacturing method according to claim 1 , wherein the second laminate has a second pressure-sensitive adhesive layer disposed on the second main surface side of the retardation member.

7. The method according to claim 6 , wherein the second pressure-sensitive adhesive layer has a thickness greater than that of the first pressure-sensitive adhesive layer.

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