Method for manufacturing a laminate and laminate

Abstract

To provide a manufacturing method of a laminate having a plurality of optical components each having an optically anisotropic layer containing a liquid crystal compound on one sheet, and high positional accuracy of each optical component and small deviation in optical characteristics of the plurality of optical components, and the laminate. An alignment film having a non-alignment region and a plurality of alignment regions is formed on a substrate, a composition containing a liquid crystal compound having a polymerizable group is applied on the alignment film to form a coating film, the liquid crystal compound in the alignment regions is aligned by heating the coating film from the substrate side, and the coating film is exposed to form an optically anisotropic layer having a non-alignment region of the liquid crystal compound and a plurality of alignment regions in which the liquid crystal compound is aligned, the thermal expansion coefficient of the substrate is 10 x 10 ‑6 / ℃ or less, the thickness is 2 mm or less, and the heating source of the coating film is separated from the substrate, thereby solving the problem.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a laminate having a plurality of optical components including an optical anisotropic layer, and the laminate manufactured by the method. Background Technology

[0002] In head-mounted displays (HMDs) such as AR (Augmented Reality) glasses, which overlay virtual images and various information onto the actual scene, and VR (Virtual Reality) glasses, which display virtual reality, various optical components with fine patterns are used.

[0003] In this type of HMD, miniaturization is a high requirement. Therefore, the optical components mounted on the HMD also need to be miniaturized.

[0004] In this regard, manufacturing each small optical component individually is very time-consuming and labor-intensive, posing problems in terms of production efficiency and cost.

[0005] Therefore, it is manufactured by arranging multiple optical components on a large substrate and then cutting them to produce individual optical components.

[0006] For example, Patent Document 1 discloses a method for manufacturing a patterned optical film, in which a strip-shaped patterned optical film having alternating first and second regions corresponding to multiple optical components along its width direction is cut in a direction parallel to the extension direction of the pattern boundary. The patterned optical film is, for example, a patterned optical film in a stereoscopic image display device in which multiple right-eye image regions and left-eye image regions are alternately formed.

[0007] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2014-164000 Summary of the Invention

[0008] The technical problem to be solved by the invention With multiple optical components formed on such a single substrate, the manufacture of various optical components can be envisioned.

[0009] One example is an optical component such as a liquid crystal lens that has an optical anisotropy layer (liquid crystal layer) using a liquid crystal compound.

[0010] When forming multiple optical components having optically anisotropic layers using liquid crystal compounds on a single substrate, for example, an alignment film is formed on the substrate, and alignment regions corresponding to the multiple optical components are formed on the alignment film. Next, a composition containing a liquid crystal compound (liquid crystal composition) is coated onto the alignment film, and drying and alignment of the liquid crystal compound are performed. Finally, the liquid crystal composition is cured to form the optically anisotropic layers.

[0011] That is, an optical sheet having multiple optical components containing optical anisotropic layers using liquid crystal compounds becomes a laminate of a substrate, an alignment film, and optical anisotropic layers.

[0012] Here, according to the research of the inventors, when multiple optical components having optical anisotropy layers containing liquid crystal compounds are formed on a single substrate, problems such as low positional accuracy of the optical components and deviations in optical properties of multiple optical components sometimes occur.

[0013] The purpose of this invention is to address the problems of the prior art and to provide a method for manufacturing a laminate having multiple optical components comprising optical anisotropic layers containing liquid crystal compounds, which enables the manufacture of a laminate with high positional accuracy of each optical component and small deviations in the optical properties of the multiple optical components, as well as a laminate manufactured by the method.

[0014] means for solving technical problems To address this issue, the present invention has the following structure.

[0015] [1] A method for manufacturing a laminate, comprising: Step 1: Forming an alignment film with non-aligned regions and multiple patterned alignment regions on a substrate; Step 2: A coating film is formed by coating a composition containing a liquid crystal compound having polymerizable groups onto an alignment film; Step 3: The liquid crystal compound in the patterned alignment area is aligned by heating the coating from the substrate side; and Step 4 involves exposing the coating to form an optically anisotropic layer containing non-oriented regions of the liquid crystal compound and multiple oriented liquid crystal regions of the liquid crystal compound. The coefficient of thermal expansion of the substrate is 10×10 -6 / ℃ below, The thickness of the substrate is less than 2mm. In step 3, the heating source of the coating is separated from the substrate while the coating is heated.

[0016] [2] According to the method for manufacturing the laminated body described in [1], wherein, In step 3, the distance between the heating source of the coating and the substrate is 0.1 to 1 mm.

[0017] [3] The method for manufacturing the laminate according to [1] or [2], wherein, The separation of the heating source and the substrate in step 3 is achieved by setting multiple pins on the heating source.

[0018] [4] According to the method for manufacturing the laminated body described in [3], wherein, Multiple pins are arranged apart from each other, with a spacing of 7 to 30 cm between them.

[0019] [5] The method for manufacturing a laminate according to any one of [1] to [4], wherein, After step 4, it has: Step 5: Peel off the alignment film and substrate from the optical anisotropic layer, or peel off the substrate from the alignment film.

[0020] [6] A laminated body having: Substrate; An orientation film having non-oriented regions and multiple patterned orientation regions; and The optical anisotropic layer includes unoriented, non-aligned regions of the liquid crystal compound and multiple oriented liquid crystal regions of the liquid crystal compound, wherein... The coefficient of thermal expansion of the substrate is 10×10 -6 / ℃ below, The thickness of the substrate is less than 2mm.

[0021] [7] According to the laminate described in [6], wherein, The distance between multiple liquid crystal alignment regions is 0.5 to 10 mm.

[0022] [8] The laminate according to [6] or [7], wherein, The liquid crystal alignment region of the optical anisotropy layer has a liquid crystal alignment pattern that changes while the orientation of the optical axis originating from the liquid crystal compound continuously rotates in at least one in-plane direction, and... When the length of a 180° rotation of the orientation of the optical axis derived from the liquid crystal compound in the plane is defined as one cycle, there are regions in the plane with different lengths of one cycle in the liquid crystal alignment pattern.

[0023] [9] The laminate according to any one of [6] to [8], wherein, The substrate is alkali-free glass with a thickness of less than 1.2mm.

[0024] Invention Effects According to the present invention, in a laminate having a plurality of optical components comprising optical anisotropic layers containing liquid crystal compounds, a laminate with high positional accuracy of each optical component and small deviation of optical properties of the plurality of optical components can be obtained. Attached Figure Description

[0025] Figure 1 This is a diagram that conceptually illustrates an example of a laminate of the present invention.

[0026] Figure 2 This is a side view conceptually illustrating an example of a liquid crystal alignment pattern in an optically anisotropic layer.

[0027] Figure 3 This is a top view conceptually illustrating an example of a liquid crystal alignment pattern in an optically anisotropic layer.

[0028] Figure 4 This is a conceptual diagram used to illustrate the role of optical anisotropic layers.

[0029] Figure 5 This is a conceptual diagram used to illustrate the role of optical anisotropic layers.

[0030] Figure 6 This is a top view that conceptually illustrates another example of a liquid crystal alignment pattern in an optically anisotropic layer.

[0031] Figure 7 This is a conceptual diagram illustrating the manufacturing method of the laminate of the present invention.

[0032] Figure 8 This is a conceptual diagram of an exposure device for an alignment film.

[0033] Figure 9 This is a conceptual diagram illustrating the manufacturing method of the laminate of the present invention.

[0034] Figure 10 This is a conceptual diagram used to illustrate embodiments of the present invention. Detailed Implementation

[0035] Hereinafter, based on the preferred embodiments shown in the accompanying drawings, the manufacturing method of the laminate and the laminate of the present invention will be described in detail.

[0036] In addition, the figures shown below are conceptual diagrams for illustrating the present invention, and the shapes, sizes, and positional relationships of the constituent elements differ from those in reality.

[0037] Furthermore, in this invention, the numerical range represented by “~” refers to the range encompassed by the numerical values ​​recorded before and after “~” as the lower and upper limits.

[0038] Moreover, in this invention, terms such as "same" and "equal" encompass the error range typically allowed in the technical field.

[0039] Figure 1The present invention conceptually illustrates an example of a laminate manufactured by the method for manufacturing a laminate of the present invention.

[0040] In addition, Figure 1 The upper section is a top view, and the lower section is a side sectional view. Additionally, in the side sectional view, the shading lines have been omitted for simplicity. (See attached diagram.) Figure 1 As shown, the laminate 10 of the present invention has a substrate 12, an alignment film 14 formed on one surface of the substrate 12, and an optical anisotropy layer 16 formed on the surface of the alignment film 14.

[0041] A top view is a view of the laminate 10 viewed from the side of the optically anisotropic layer 16 in the thickness direction; that is, a view of the laminate 10 viewed from the side of the optically anisotropic layer 16 in the stacking direction of the substrate 12, the alignment film 14, and the optically anisotropic layer 16. A side sectional view is a sectional view of the laminate 10 cut along the thickness direction.

[0042] The laminate 10 of the present invention is formed by forming a plurality of optical components (optical elements) on a sheet (film, plate).

[0043] In the example shown in the figure, on a single laminate 10, the optical components 20 shown in the figure are arranged at equal intervals in two orthogonal directions, forming a total of 30 components in the form of 5 x 6.

[0044] Therefore, in the alignment film 14, the portion in which the optical component 20 is formed becomes the pattern alignment region in the present invention, and the other regions become the non-alignment region in the present invention.

[0045] Furthermore, in the optical anisotropy layer 16, the area where the optical component 20 is formed becomes the liquid crystal alignment region in this invention, and the other areas become the non-alignment region in this invention.

[0046] In the laminate of the present invention, the coefficient of thermal expansion of the substrate 12 is 10 × 10⁻⁶. -6 Temperatures below ℃ and thicknesses below 2mm. This will be discussed in detail later.

[0047] In the laminate 10 of the present invention, the substrate 12 can be made of various known sheet materials as long as the above conditions are met.

[0048] As a substrate, examples include substrates formed of glass, triacetyl cellulose (TAC), polyethylene terephthalate (PET), polycarbonate, polyvinyl chloride, acrylic acid, and polyolefins. Glass is preferably shown, and alkali-free glass is more preferably shown.

[0049] An alignment film 14 is formed on the surface of the substrate 12.

[0050] The alignment film 14 is an alignment film used to align the liquid crystal compound into a predetermined liquid crystal alignment pattern when forming the optical anisotropic layer 16.

[0051] As described above, in the laminate 10 of the present invention, the alignment film 14 has a plurality of patterned alignment regions corresponding to the optical components 20 arranged at equal intervals in two orthogonal directions and other regions, namely, unaligned regions.

[0052] In the alignment film 14, the patterned alignment region refers to a region in the optical anisotropy layer 16 where an alignment pattern corresponding to the liquid crystal alignment pattern in the liquid crystal alignment region corresponding to the optical component 20 is formed. On the other hand, in the alignment film 14, the unaligned region refers to a region that does not have such an alignment pattern.

[0053] The alignment pattern in the alignment region, i.e. the liquid crystal alignment pattern in the liquid crystal alignment region of the optical anisotropic layer described later, is not limited, and various known liquid crystal alignment patterns corresponding to optical components 20 such as liquid crystal diffraction elements, liquid crystal lenses (focusing / diverging liquid crystal diffraction elements), light diffusion plates (diffusers), holographic elements, wavelength conversion plates, and optical filters can be used.

[0054] Preferably, a liquid crystal alignment pattern is shown where the orientation of the optical axis originating from the liquid crystal compound changes while continuously rotating in one in-plane direction. More preferably, a liquid crystal alignment pattern is shown where the liquid crystal alignment pattern is formed in concentric circles from the inside to the outside (see reference). Figure 6 ).

[0055] Furthermore, in this invention, when the length of the orientation of the optical axis derived from the liquid crystal compound rotating 180° in the plane is set as one cycle, it is preferable to have a region in the plane having a different length of one cycle in the liquid crystal alignment pattern.

[0056] The alignment film 14 can also utilize various known alignment films used to align liquid crystal compounds.

[0057] Examples include triboelectric films made of organic compounds such as polymers, tilted vapor-deposited films of inorganic compounds, films with microgrooves, and films formed by stacking LB (Langmuir-Blodgett) films based on the Langmuir-Blodgett process of organic compounds such as ω-trisanoic acid, dioctadecylmethylammonium chloride, and methyl stearate.

[0058] The orientation film 14 based on friction treatment can be formed by rubbing the surface of the polymer layer multiple times in a specified direction with paper or cloth.

[0059] As the material used in the alignment film 14, polyimide, polyvinyl alcohol, polymers with polymerizable groups as described in Japanese Patent Application Publication No. 9-152509, and materials used in the formation of the alignment film 14 as described in Japanese Patent Application Publication Nos. 2005-97377, 2005-99228, and 2005-128503 are preferred.

[0060] The alignment film 14 is preferably formed by irradiating polarized or unpolarized light with a material that exhibits photoorientation, and is thus called a photoalignment film. That is, in this invention, the alignment film 14 is preferably formed by coating a photoalignment material onto a substrate 12.

[0061] Polarized light can illuminate the photo-alignment film from a vertical or oblique direction, while unpolarized light can illuminate the photo-alignment film from an oblique direction.

[0062] In this invention, as the photoalignment material used in the alignment film, the following compounds are examples of preferred embodiments: Japanese Patent Application Publication No. 2006-285197, Japanese Patent Application Publication No. 2007-76839, Japanese Patent Application Publication No. 2007-138138, Japanese Patent Application Publication No. 2007-94071, Japanese Patent Application Publication No. 2007-121721, Japanese Patent Application Publication No. 2007-140465, and so on. Japanese Patent Application Publication No. 2007-156439, Japanese Patent Application Publication No. 2007-133184, Japanese Patent Application Publication No. 2009-109831, Japanese Patent No. 3883848 and Japanese Patent No. 4151746, aromatic ester compounds described in Japanese Patent Application Publication No. 2002-229039, Japanese Patent Application Publication No. 2002-265541 and Japanese Patent Application Publication No. 2002-317 The maleimide and / or alkenyl-substituted nadicimide compounds having photo-orientation units described in Japanese Patent No. 013, the photocrosslinkable silane derivatives described in Japanese Patent Nos. 4205195 and 4205198, the photocrosslinkable polyimides, photocrosslinkable polyamides and... described in Japanese Patent Nos. 2003-520878, 2004-529220 and 4162850, and Japanese Patent No. 4162850 Photocrosslinkable polyesters and photodimerizable compounds, particularly cinnamic acid ester compounds, chalcone compounds and coumarin compounds, as described in Japanese Patent Application Publication Nos. 9-118717, 10-506420, 2003-505561, International Publication No. 2010 / 150748, 2013-177561 and 2014-12823.

[0063] Among them, azo compounds, photocrosslinked polyimides, photocrosslinked polyamides, photocrosslinked polyesters, cinnamic acid ester compounds, and chalcone compounds can be preferentially utilized.

[0064] There is no limitation on the thickness of the alignment film 14. As long as the thickness is appropriately set according to the forming material of the alignment film 14, the required alignment function can be obtained.

[0065] The thickness of the alignment film 14 is preferably 2 nm to 5 μm, more preferably 5 nm to 2 μm, even more preferably 10 nm to 1 μm, and especially preferably 30 to 200 nm.

[0066] There are no limitations on the method of forming the alignment film 14, and various known methods corresponding to the forming materials of the alignment film 14 can be used. As an example, the following method can be illustrated: after coating the alignment film 14 on the surface of the substrate 12 and drying it to form an unexposed alignment film, the alignment film 14 is subjected to interference exposure to form an alignment pattern, thereby producing the alignment film 14.

[0067] This viewpoint will be discussed later.

[0068] An optically anisotropic layer 16 is formed on the alignment film 14.

[0069] As described above, in the laminate 10 of the present invention, the optical anisotropy layer 16 has a plurality of liquid crystal orientation regions oriented according to a predetermined orientation pattern of the liquid crystal compound corresponding to the optical component 20, and non-oriented regions of the liquid crystal compound that are not oriented, which are other than the liquid crystal compound orientation regions.

[0070] The optical anisotropy layer 16 can be formed by coating a composition containing a rod-shaped liquid crystal compound or a disk-shaped liquid crystal compound with polymerizable groups onto an alignment film 14 to form a coating film, drying the coating film and aligning the liquid crystal compound, and then curing the composition containing the liquid crystal compound.

[0071] In the following description, compositions containing liquid crystal compounds will also be referred to as liquid crystal compositions.

[0072] -Rod-shaped liquid crystal compounds- As rod-shaped liquid crystal compounds, preferably used are methylimine derivatives, azo derivatives, cyanobiphenyl derivatives, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexane derivatives, cyano-substituted phenylpyrimidine derivatives, alkoxy-substituted phenylpyrimidine derivatives, phenyl dioxane derivatives, diphenylacetylene derivatives, and alkenylcyclohexylbenzyl nitrile derivatives. In addition to the above low-molecular-weight liquid crystal molecules, high-molecular-weight liquid crystal molecules can also be used.

[0073] In the optical anisotropic layer 36, the orientation of the rod-shaped liquid crystal compound is fixed by polymerization.

[0074] As polymerizable rod-shaped liquid crystal compounds, compounds described in Makromol. Chem., Vol. 190, pp. 2255 (1989), Advanced Materials, Vol. 5, pp. 107 (1993), U.S. Patent No. 4,683,327, U.S. Patent No. 5,622,648, U.S. Patent No. 5,770,107, International Publication No. 95 / 22586, International Publication No. 95 / 24455, International Publication No. 97 / 00600, International Publication No. 98 / 23580, International Publication No. 98 / 52905, Japanese Patent Application Publication No. 1-272,551, Japanese Patent Application Publication No. 6-16616, Japanese Patent Application Publication No. 7-110,469, Japanese Patent Application Publication No. 11-80081, and Japanese Patent Application Publication No. 2001-64627 are applicable. Furthermore, as a rod-shaped liquid crystal compound, the rod-shaped liquid crystal compounds described in Japanese Patent Application Publication No. 11-513019 and Japanese Patent Application Publication No. 2007-279688 are preferred.

[0075] Furthermore, as polymerizable liquid crystal compounds other than those described above, cyclic organopolysiloxane compounds having a cholesterol phase, as disclosed in Japanese Patent Application Publication No. 57-165480, can be used. Moreover, as polymeric liquid crystal compounds, polymers with mesocrystalline groups for displaying liquid crystals incorporated into the main chain, side chain, or both the main chain and side chain, cholesteric liquid crystals with cholesterol groups incorporated into the side chains, liquid crystal polymers such as those disclosed in Japanese Patent Application Publication No. 9-133810, and liquid crystal polymers such as those disclosed in Japanese Patent Application Publication No. 11-293252 can be used.

[0076] -Disc-shaped liquid crystal compound- As a disc-shaped liquid crystal compound, the disc-shaped liquid crystal compounds described in Japanese Patent Application Publication No. 2007-108732 and Japanese Patent Application Publication No. 2010-244038 are preferred, for example.

[0077] In addition, when a disk-shaped liquid crystal compound is used for the liquid crystal layer, the liquid crystal compound 40 rises in the thickness direction in the liquid crystal layer, and the optical axis derived from the liquid crystal compound is defined as an axis perpendicular to the disk surface, i.e., the so-called fast axis.

[0078] The liquid crystal composition is preferably used as a liquid when forming the optical anisotropic layer 16.

[0079] Therefore, the liquid crystal composition may contain a solvent. The solvent is not limited and can be appropriately selected according to the purpose, but organic solvents are preferred.

[0080] There are no restrictions on the organic solvents used; they can be appropriately selected according to the purpose. Examples include ketones, haloalkanes, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, and ethers. They can be used alone or in combination of two or more. Among these, ketones are preferred, considering their environmental impact.

[0081] In addition to liquid crystal compounds, chiral reagents, surfactants, leveling agents, orientation control agents, polymerization initiators, crosslinking agents, orientation aids, polymerization inhibitors, antioxidants, ultraviolet absorbers, light stabilizers, pigments, and metal oxide particles may be added to optical compositions as needed, without reducing optical performance.

[0082] Furthermore, the amount of liquid crystal compound added in the liquid crystal composition is preferably 75 to 99.9% by mass relative to the mass of the solid components of the liquid crystal composition (mass after removing the solvent), more preferably 80 to 99% by mass, and even more preferably 85 to 90% by mass.

[0083] As described above, in the laminate 10 of the present invention, the liquid crystal alignment pattern in the liquid crystal alignment region of the optical anisotropic layer 16 is not limited.

[0084] As a preferred liquid crystal alignment pattern, an example can be a liquid crystal alignment pattern in which the orientation of the optical axis derived from the liquid crystal compound changes while rotating continuously in at least one direction within the plane of the optical anisotropy layer.

[0085] exist Figure 2 The image shows a side view of an optically anisotropic layer having the liquid crystal alignment pattern. Furthermore, in... Figure 3 The image shows a top view of the optically anisotropic layer having the liquid crystal alignment pattern. The side and top views follow the same pattern described above. Figure 1 .

[0086] Furthermore, in the laminate 10 of the present invention, in the non-aligned region, the liquid crystal compound is not aligned, originating from the optical axis of the liquid crystal compound being oriented in an irregular in-plane direction.

[0087] exist Figure 2 and Figure 3 The optical anisotropy layer shown has a liquid crystal alignment pattern in which the orientation of the optical axis 40A originating from the liquid crystal compound 40 changes as it rotates continuously in one direction within the plane of the optical anisotropy layer.

[0088] Furthermore, the optical axis 40A derived from the liquid crystal compound 40 is the axis with the highest refractive index in the liquid crystal compound 40, the so-called slow axis. Figure 2 and Figure 3In this example, liquid crystal compound 40 is a rod-shaped liquid crystal compound. Therefore, in liquid crystal compound 40, the optical axis 40A is along the long axis direction of the rod shape. Furthermore, as described above, when the liquid crystal compound is a disk-shaped liquid crystal compound, the optical axis is in a direction orthogonal to the disk surface.

[0089] like Figure 3 As shown, on the surface of the alignment film 14, the liquid crystal compound 40 constituting the alignment region of the optical anisotropy layer 16 has a liquid crystal alignment pattern such that, according to the alignment pattern formed on the lower alignment film 14, the orientation of the optical axis 40A changes while continuously rotating in a predetermined direction indicated by arrow D (hereinafter referred to as alignment axis D) within the plane of the alignment region of the optical anisotropy layer 16. In the example shown, the liquid crystal alignment pattern shows that the optical axis 40A of the liquid crystal compound 40 changes while continuously rotating clockwise along the alignment axis D.

[0090] The liquid crystal compound 40 constituting the orientation region of the optical anisotropy layer 16 is arranged in a two-dimensional state in a direction orthogonal to the alignment axis D and the direction of the alignment axis D.

[0091] In the following description, for convenience, the direction orthogonal to the alignment axis direction is designated as the Y direction. That is, the arrow Y direction refers to a direction orthogonal to a direction whose orientation changes continuously within the plane of the alignment region of the optical anisotropy layer 16 as the optical axis 40A of the liquid crystal compound 40 rotates. Therefore, in Figure 4 and Figure 5 In this case, the Y direction becomes the direction orthogonal to the plane of the paper.

[0092] The orientation of the optical axis 40A of the liquid crystal compound 40 changes as it rotates continuously along the arrangement axis D (a specified direction). Specifically, the angle between the optical axis 40A of the liquid crystal compound 40 arranged along the arrangement axis D and the arrangement axis D varies depending on the position of the arrangement axis D. Along the arrangement axis D, the angle between the optical axis 40A and the arrangement axis D changes sequentially from θ to θ+180° or θ-180°.

[0093] Furthermore, the angle difference between the optical axes 40A of the liquid crystal compounds 40 that are adjacent to each other in the direction of the arrangement axis D is preferably 45° or less, more preferably 15° or less, and even more preferably a smaller angle.

[0094] exist Figure 2 and Figure 3 In the orientation region of the optical anisotropy layer 16 shown, the optical axis 40A of the liquid crystal compound 40 rotates to the right (clockwise) along the direction of the arrow on the alignment axis D.

[0095] On the other hand, the orientation of the optical axis 40A is equal in the Y direction, which is orthogonal to the alignment axis D direction, i.e., the direction of the optical axis 40A, while the liquid crystal compound 40 forming the alignment region of the optical anisotropic layer 16 rotates continuously.

[0096] In other words, in the Y direction, the optical axis 40A of the liquid crystal compound 40 forming the orientation region of the optical anisotropic layer 16 is at the same angle as the alignment axis D.

[0097] In the orientation region of the optical anisotropy layer 16, the optical axis 40A of the liquid crystal compounds arranged in the Y direction forms an angle equal to that of the arrangement axis D. The arrangement axis D refers to a direction in which the orientation of the optical axis of the liquid crystal compound 40 changes as it rotates continuously.

[0098] The region in the Y direction where the liquid crystal compound 40 is arranged with the optical axis 40A and the arrangement axis D at an angle equal to that of the liquid crystal compound 40A is designated as region R.

[0099] At this point, the value of the in-plane delay (Re) in each region R is preferably half a wavelength, i.e., λ / 2.

[0100] The in-plane delay is calculated by multiplying the refractive index difference Δn associated with the refractive index anisotropy of region R by the thickness of the liquid crystal layer. The refractive index difference associated with the refractive index anisotropy of region R in the liquid crystal layer is defined as the difference between the refractive index along the slow axis in the plane of region R and the refractive index in a direction orthogonal to the slow axis. That is, the refractive index difference Δn associated with the refractive index anisotropy of region R is equal to the difference between the refractive index of the liquid crystal compound 40 along the optical axis 40A and the refractive index of the liquid crystal compound 40 in the plane of region R perpendicular to the optical axis 40A. In other words, the aforementioned refractive index difference Δn is equal to the refractive index difference of the liquid crystal compound.

[0101] Furthermore, in the liquid crystal alignment pattern having an optical anisotropy layer 16 in a concentric circle shape where the optical axis 40A is continuously rotated in one direction (described later), the regions where the optical axis 40A is centered and formed in a ring shape with the same orientation are equivalent to... Figure 3 Region R in the middle.

[0102] In the orientation region of the optical anisotropic layer 16, in the liquid crystal orientation pattern of this liquid crystal compound 40, in the direction of the arrangement axis D which changes due to continuous rotation of the in-plane optical axis 40A, the length (length Λ (distance)) of rotating the optical axis 40A of the liquid crystal compound 40 by 180° is set as one period Λ in the liquid crystal orientation pattern.

[0103] That is, the distance between the centers of two liquid crystal compounds 40 with equal angles relative to the alignment axis D along the alignment axis D is defined as the length Λ of one period. Specifically, as... Figure 3 As shown, the distance between the centers of the two liquid crystal compounds 40 whose alignment axis D direction is consistent with the direction of the optical axis 40A is set as one period Λ.

[0104] The liquid crystal alignment pattern of the alignment region of the optical anisotropic layer 16 repeats one cycle Λ in a direction that changes as the orientation of the alignment axis D, i.e. the optical axis 40A, rotates continuously.

[0105] The liquid crystal alignment region of this optical anisotropic layer 16 has the effect of refracting incident circularly polarized light and changing the polarization direction of the circularly polarized light.

[0106] use Figure 4 and Figure 5 The conceptual diagram shown illustrates the function of the liquid crystal alignment region in the optical anisotropy layer 16.

[0107] Furthermore, in the liquid crystal alignment region of the optical anisotropy layer 16, the product of the refractive index difference of the liquid crystal compound and the thickness of the optical element is λ / 2. And, in Figure 4 and Figure 5 In order to show the rotation direction of the optical axis in the liquid crystal alignment pattern of the liquid crystal alignment region of the optical anisotropy layer 16, only the surface liquid crystal compound 40 is shown, but the liquid crystal alignment region of the optical anisotropy layer 16 is as follows: Figure 2 The orientation region having a stacked optical anisotropic layer 16 as shown.

[0108] like Figure 4 As shown, when the product of the refractive index difference of the liquid crystal compound in the liquid crystal alignment region of the optical anisotropic layer 16 and the thickness of the liquid crystal alignment region of the optical anisotropic layer 16 is λ / 2, if the incident light L1, which is left-handed circularly polarized light, is incident on the liquid crystal alignment region of the optical anisotropic layer 16, the incident light L1 is given a phase difference of 180° through the liquid crystal alignment region of the optical anisotropic layer 16, and the transmitted light L2 is converted into right-handed circularly polarized light.

[0109] Furthermore, the liquid crystal alignment pattern formed in the liquid crystal alignment region of the optical anisotropic layer 16 is a periodic pattern along the alignment axis D, therefore the transmitted light L2 travels in a direction different from the direction of travel of the incident light L1. Thus, the incident light L1, which is left-handed circularly polarized, is converted into transmitted light L2, which is right-handed circularly polarized, tilted only at a predetermined angle relative to the incident direction along the alignment axis D. Figure 4 In the example shown, the transmitted light L2 is diffracted to travel in a downward-right direction.

[0110] On the other hand, such as Figure 5 As shown, when the product of the refractive index difference of the liquid crystal compound in the liquid crystal alignment region of the optical anisotropic layer 16 and the thickness of the alignment region of the optical anisotropic layer 16 is λ / 2, if the incident light L4 of right-hand circularly polarized light is incident on the liquid crystal alignment region of the optical anisotropic layer 16, the incident light L4 is given a phase difference of 180° through the liquid crystal alignment region of the optical anisotropic layer 16, and is thus converted into the transmitted light L5 of left-hand circularly polarized light.

[0111] Furthermore, the liquid crystal alignment pattern formed in the liquid crystal alignment region of the optical anisotropic layer 16 is a periodic pattern along the alignment axis D. Therefore, the transmitted light L5 travels in a direction different from the direction of travel of the incident light L4. At this time, the transmitted light L5 travels in a direction different from the transmitted light L2, that is, in a direction opposite to the direction of the arrow on the alignment axis D relative to the incident direction. Thus, the incident light L4 is converted into transmitted light L5, which is left-handed circularly polarized light tilted at a predetermined angle relative to the incident direction in a direction opposite to the alignment axis D. Figure 5 In the example shown, the transmitted light L5 is diffracted to travel in a downward-left direction.

[0112] That is, the optical anisotropic layer 16 with this liquid crystal alignment pattern is a liquid crystal diffraction element.

[0113] The liquid crystal alignment region of the optical anisotropic layer 16 can adjust the refraction angles of transmitted light L2 and L5 according to the length of one period Λ of the formed liquid crystal alignment pattern.

[0114] Specifically, in the liquid crystal alignment region of the optical anisotropy layer 16, the shorter one period Λ of the liquid crystal alignment pattern, the stronger the interference between the light passing through the adjacent liquid crystal compounds, thus enabling the transmitted light L2 and L5 to be refracted significantly.

[0115] Therefore, the optical anisotropy layer 16 has regions that are different in one period Λ within the plane, thereby allowing the refraction direction (diffraction direction) of light to be adjusted and used as various optical components. For example, by gradually shortening one period Λ towards the alignment axis D, an optical component that diffracts incident light in a manner that causes left-handed circularly polarized light to diverge and right-handed circularly polarized light to focus can be obtained.

[0116] Furthermore, by setting the rotation direction of the optical axis 40A of the liquid crystal compound rotating along the alignment axis D to the opposite direction, it is possible to set the direction of refraction of transmitted light to the opposite direction.

[0117] That is, in Figures 2-5 In the example shown, the optical axis 40A, which is oriented towards the alignment axis D, rotates clockwise. However, by setting this rotation direction to counterclockwise, the direction of refraction of the transmitted light can be reversed. Specifically, in Figure 4 and Figure 5 In the diagram, when the optical axis 40A, which is oriented towards the alignment axis D, rotates counterclockwise, left-handed circularly polarized light incident on the liquid crystal alignment region of the optical anisotropic layer 16 from the upper side is converted into right-handed circularly polarized light upon transmission through the liquid crystal alignment region of the optical anisotropic layer 16, and is diffracted to travel in the lower left direction of the diagram. Conversely, right-handed circularly polarized light incident on the liquid crystal alignment region of the optical anisotropic layer 16 from the upper side is converted into left-handed circularly polarized light upon transmission through the liquid crystal alignment region of the optical anisotropic layer 16, and is diffracted to travel in the lower right direction of the diagram.

[0118] As described above, in the laminate 10 of the present invention, the liquid crystal alignment region of the optical anisotropy layer 16 is more preferably exemplified as having a liquid crystal alignment pattern that changes while continuously rotating in one direction from the optical axis of the liquid crystal compound 40, and the liquid crystal alignment pattern having a concentric circle shape from the inside to the outside.

[0119] exist Figure 1 In the stack 10 shown, the regions of the alignment film 14 and the optical anisotropic layer 16 corresponding to the optical component 20 have the concentric liquid crystal alignment pattern. That is, in the stack 10, the pattern alignment region of the alignment film 14 and the liquid crystal alignment region of the optical anisotropic layer 16 have the concentric liquid crystal alignment pattern.

[0120] exist Figure 6 The diagram conceptually shows a top view of the liquid crystal alignment region of the optical anisotropic layer 16 having the concentric liquid crystal alignment pattern, i.e., a top view of the optical component 20 having the liquid crystal alignment pattern.

[0121] Furthermore, in the liquid crystal alignment region of the optical anisotropy layer 16, the alignment of the liquid crystal compound 40 follows the alignment pattern formed in the pattern alignment region of the alignment film 14. Therefore, the same alignment pattern is also formed in the pattern alignment region of the alignment film 14.

[0122] Figure 6 The liquid crystal alignment region of the optical anisotropy layer 16 shown, which corresponds to the optical component 20, has a liquid crystal alignment pattern that changes as it rotates continuously in one direction from the optical axis originating from the liquid crystal compound 40 in a concentric circle shape from the inside to the outside.

[0123] Right now, Figure 6 The liquid crystal alignment pattern of the liquid crystal alignment region of the optical anisotropy layer 16 shown changes in a direction that is continuously rotated from the inside to the outside in a radial pattern originating from the optical axis of the liquid crystal compound 40.

[0124] In addition, Figure 6Similarly, as described above, a rod-shaped liquid crystal compound is shown as liquid crystal compound 40. Therefore, as mentioned above, the direction of the optical axis of liquid crystal compound 40 is aligned with the length direction of liquid crystal compound 40.

[0125] Specifically, in the liquid crystal alignment region of the optical anisotropy layer 16, the direction of the optical axis of the liquid crystal compound 40 changes continuously while rotating along multiple directions from the center of the liquid crystal alignment region of the optical anisotropy layer 16 outward, such as the direction indicated by arrow D1, the direction indicated by arrow D2, the direction indicated by arrow D3, the direction indicated by arrow D4, etc.

[0126] In the liquid crystal alignment region of the optical anisotropy layer 16, the rotation direction of the optical axis of the liquid crystal compound 40 is the same in all directions, i.e., in all one direction. In the example shown in the figure, the rotation direction of the optical axis of the liquid crystal compound 40 is counterclockwise in all directions indicated by arrows D1, D2, D3, and D4.

[0127] That is, if arrows D1 and D4 are considered as a straight line, then along this line, at the center of the liquid crystal alignment region of the optical anisotropy layer 16, the rotation direction of the optical axis of the liquid crystal compound 40 is reversed. As an example, let the straight line formed by arrows D1 and D4 point to the right in the figure (the direction of arrow D1). In this case, the optical axis of the liquid crystal compound 40 initially rotates clockwise from the outside of the liquid crystal alignment region of the optical anisotropy layer 16 toward the center, then reverses at the center of the liquid crystal alignment region of the optical anisotropy layer 16, and then rotates counterclockwise from the center of the liquid crystal alignment region of the optical anisotropy layer 16 toward the outside.

[0128] Furthermore, the liquid crystal alignment region of the optical anisotropy layer 16 has a liquid crystal alignment pattern with a period Λ that gradually shortens from the inner side to the outer side of the concentric circles.

[0129] In having such Figure 6 In the liquid crystal alignment region of the optical anisotropy layer 16 with the concentric circular liquid crystal alignment pattern shown, the directions of the arrows D1, D2... from the center outwards correspond to... Figure 5 The arrangement axis D in the equations is such that each circle of the concentric circles is equivalent to... Figure 5 The arrow Y direction (region R) is shown in the diagram. Therefore, in the liquid crystal alignment region of the optical anisotropic layer 16 with a concentric circle liquid crystal alignment pattern, the orientation of the length direction of the liquid crystal compound 40, i.e., the direction of the optical axis, is equal in each of the concentric circles.

[0130] In having such Figure 6In the liquid crystal alignment region of the optically anisotropic layer 16 with the concentric liquid crystal alignment pattern shown, the incident light is also diffracted in the same way as in the optically anisotropic layer with the liquid crystal alignment pattern having an optical axis that changes while rotating relative to the direction of the arrow D in one of the aforementioned directions.

[0131] Therefore, having as Figure 6 The liquid crystal alignment region of the optical anisotropy layer 16 of the concentric liquid crystal alignment pattern shown causes the incident light to diffract toward the center of the concentric circle, or causes the incident light to diffract outward from the center of the concentric circle.

[0132] Here, as described above, one period Λ of the liquid crystal alignment pattern in the liquid crystal alignment region of the optical anisotropy layer 16 gradually shortens from the inside to the outside of the concentric circles. Therefore, the liquid crystal alignment region of the optical anisotropy layer 16, depending on the rotation direction of the circularly polarized light, either focuses the transmitted light towards the center of the concentric circles or diverges the transmitted light from the center of the concentric circles outwards. In other words, the liquid crystal alignment region of the optical anisotropy layer 16 functions like a convex lens for focusing light or a concave lens for diverging light, depending on the rotation direction of the incident circularly polarized light. That is, the optical component 20 is a liquid crystal lens (liquid crystal diffraction lens).

[0133] Furthermore, there is no limitation on the thickness of the optical anisotropic layer. The desired optical properties can be obtained by appropriately setting the thickness according to the forming material of the optical anisotropic layer, such as liquid crystal compound.

[0134] The following is for reference. Figure 7 The conceptual diagram illustrates the manufacturing method of the laminate of the present invention 10.

[0135] Figure 7 In the manufacturing method shown, the substrate 12 is cleaned from the upper left side, an unexposed alignment film 14a is formed, an alignment film 14 is formed by exposing the unexposed alignment film, a coating film is formed by coating a liquid crystal composition, the liquid crystal composition is dried and aligned, and an optical anisotropic layer 16 is formed by curing the liquid crystal composition, thereby manufacturing the laminate 10 of the present invention.

[0136] In addition, Figure 7 In the example shown, as a preferred example, after manufacturing the laminate 10, the substrate 12 and the alignment film 14 are peeled off from the optical anisotropic layer 16.

[0137] exist Figure 7 In the manufacturing method shown, firstly, as Figure 7 As shown on the upper left side, the substrate 12 is cleaned.

[0138] There are no restrictions on the cleaning method of the substrate 12, and various known methods corresponding to the forming materials and dimensions of the substrate 12 can be used.

[0139] Examples include ultrasonic cleaning, cleaning with cleaning fluid, cleaning with ultraviolet light, cleaning with a brush, and cleaning using the collision force of two fluids. Multiple of these cleaning methods can be used in combination.

[0140] Next, if the cleaned substrate 12 is dried, then as follows Figure 7 As shown in the second image from the left in the upper section, a composition forming an alignment film 14 is coated onto one surface of a substrate 12 and dried, thereby forming an unexposed alignment film 14a. Next, as... Figure 7 The third one from the left in the upper section shows that an alignment film 14 with an unaligned region and multiple patterned alignment regions corresponding to the optical component 20 is formed by exposing the unexposed alignment film 14a (step 1).

[0141] like Figure 7 As shown in the second image from the left in the upper section, the unexposed alignment film 14a is formed by coating the composition that will become the alignment film onto the surface of the cleaned substrate 12 and then drying it.

[0142] exist Figure 7 In the example shown, as a preferred embodiment, an unexposed photoalignment film, namely the unexposed alignment film 14a, is formed by coating the composition containing the aforementioned photoalignment material onto the substrate 12 and drying it. Furthermore, the coating unit 54 for the composition that forms the alignment film is not limited, and various known mechanisms can be used, similar to the coating unit 52 for the liquid crystal composition described later. Moreover, the drying of the composition can be performed using any known method corresponding to the composition.

[0143] Next, as Figure 7 The third one from the left in the upper section is shown. The positions of the unexposed alignment film 14a corresponding to the optical component 20 are exposed sequentially to form an alignment film 14 with an unaligned region and a patterned alignment region.

[0144] As mentioned above, in this example, such as Figure 6 As shown, the pattern alignment region, i.e. the liquid crystal alignment region of the optical anisotropic layer 16, i.e. the optical component 20, has a liquid crystal alignment pattern that changes as it rotates continuously in one direction from the inside to the outside in a concentric circle shape, with the orientation of the optical axis originating from the liquid crystal compound 40.

[0145] Figure 8 The image shows, conceptually, an example of an exposure apparatus for forming such concentric circular alignment patterns on an alignment film.

[0146] like Figure 8The exposure apparatus 80 shown includes a light source 84 with a laser 82, a polarization beam splitter 86 that splits the laser beam M from the laser 82 into S-polarized light MS and P-polarized light MP, a reflector 90A disposed in the optical path of P-polarized light MP and a reflector 90B disposed in the optical path of S-polarized light MS, a lens 92 disposed in the optical path of S-polarized light MS, a beam splitter 94, and a λ / 4 plate 96.

[0147] The P-polarized light MP, split by polarization beam splitter 86, is reflected by mirror 90A and incident on beam splitter 94. On the other hand, the S-polarized light MS, split by polarization beam splitter 86, is reflected by mirror 90B, focused by lens 92, and incident on beam splitter 94.

[0148] P-polarized light MP and S-polarized light MS are combined by beam splitter 94, passed through λ / 4 plate 96 to become right-hand circularly polarized light and left-hand circularly polarized light corresponding to the polarization direction, and incident on the unexposed alignment film 14a on substrate 12.

[0149] Here, the beams are combined by the beam splitter 94 and passed through the λ / 4 plate 96 to become right-handed and left-handed circularly polarized light corresponding to their polarization directions, which interfere with each other. Furthermore, one type of circularly polarized light is parallel light, while the other type is circularly polarized light focused by the lens 92.

[0150] Through the interference of right-handed and left-handed circularly polarized light, the polarization state of the light illuminating the unexposed alignment film 14a changes periodically in the form of interference fringes. Furthermore, in this interference exposure, the cross angle between the left-handed and right-handed circularly polarized light changes from the inner to the outer side of the concentric circles, thus obtaining an exposure pattern where one period Λ shortens from the inner to the outer side. Therefore, a concentric circular alignment pattern in which the alignment state changes periodically can be obtained in the unexposed alignment film 14a.

[0151] In this exposure apparatus 80, the length Λ of one cycle of the liquid crystal alignment pattern, which changes as the optical axis of the liquid crystal compound 40 rotates continuously by 180°, can be controlled by changing the refractive power (F-number of lens 92), the focal length of lens 92, and the distance between lens 92 and the unexposed alignment film 14a.

[0152] Furthermore, by adjusting the refractive power of lens 92, the length Λ of one cycle of the liquid crystal alignment pattern can be changed in one direction while the optical axis rotates continuously. Specifically, the length Λ of one cycle of the liquid crystal alignment pattern can be changed in one direction while the optical axis rotates continuously by adjusting the diffusion angle of the light diffused through lens 92 that interferes with parallel light. More specifically, if the refractive power of lens 92 is reduced, the light becomes closer to parallel, so the length Λ of one cycle of the liquid crystal alignment pattern gradually shortens from the inside to the outside, and the F-value increases. Conversely, if the refractive power of lens 92 is increased, the length Λ of one cycle of the liquid crystal alignment pattern shortens sharply from the inside to the outside, and the F-value decreases.

[0153] Thus, when forming a liquid crystal alignment pattern by exposing the unexposed alignment film 14a, the reflectivity of the laser beam emitted by the laser 82 of the exposure apparatus 80 on the back side of the substrate 12, i.e. the side of the substrate 12 opposite to the unexposed alignment film 14a, is preferably 1% or less.

[0154] That is, the reflectance of the exposure light on the back side of the substrate 12 that exposes the unexposed alignment film 14a to form a patterned alignment area (alignment film) is preferably 1% or less.

[0155] When the unexposed alignment film 14a is exposed, the exposure light incident on the laminate of the unexposed alignment film 14a and the substrate 12 is sometimes reflected at the interface between the back side of the substrate 12 and the air, and then incident on the unexposed alignment film 14a again. This light can become an interference that hinders the proper exposure of the unexposed alignment film 14a, and sometimes the properly aligned patterned area (alignment film 14) cannot be formed.

[0156] To prevent this inconvenience, the reflectivity of the exposed light on the back side of the substrate 12 is preferably less than 1%.

[0157] There are no limitations on the method of setting the reflectivity of the exposure light in the back side of the substrate 12 to 1% or less, and various known methods corresponding to the exposure light can be used.

[0158] For example, ultraviolet light is mostly used in the exposure of photo-aligned films. In this case, as a method to set the reflectivity of the exposure light in the back side of the substrate 12 to 1% or less, examples include setting the back side of the substrate 12 to black or applying an anti-reflective film (AR coating) specifically for the wavelength range of ultraviolet light to the back side of the substrate 12.

[0159] exist Figure 1 In the laminate 10 shown, there are 30 optical components 20 arranged at equal intervals, with 5 horizontal and 6 vertical 5×6 units. That is, the alignment film 14 of the laminate 10 has 30 pattern alignment regions arranged at equal intervals of 5×6.

[0160] Correspondingly, during the exposure of the unexposed alignment film 14a, based on the positions of the 30 optical components 20 arranged at equal intervals of 5×6, exposure and movement of the exposure apparatus 80 are repeatedly performed to form pattern alignment regions at the 30 locations corresponding to the optical components 20. Furthermore, in Figure 7 In the diagram, for the sake of simplicity, only the beam splitter 94 is shown in the exposure apparatus 80.

[0161] Thus, an orientation film 14 is formed having 30 patterned orientation regions arranged at equal intervals of 5×6 and other unexposed, unoriented regions.

[0162] Next, as Figure 7 As shown on the right side of the upper section, a liquid crystal composition is coated to form an optical anisotropic layer 16 to form a coating film of the liquid crystal composition (step 2).

[0163] As described above, the liquid crystal composition that forms the optical anisotropy layer 16 is preferably a liquid containing a rod-shaped liquid crystal compound or a disk-shaped liquid crystal compound. Furthermore, as described above, surfactants and polymerization initiators may be appropriately added to the liquid crystal composition that forms the optical anisotropy layer 16 as needed.

[0164] The coating unit 52 for the liquid crystal composition is not limited, and any coating unit (coating apparatus) capable of uniformly coating liquid onto a sheet can be used. Examples include printing units such as inkjet and roll printing, as well as coating units such as die coating, gravure coating, spin coating, bar coating, and spray coating.

[0165] Next, as Figure 7 As shown on the left side of the lower section, the liquid crystal composition coating formed by heating from the substrate 12 side is dried, and the liquid crystal compound in the patterned alignment region of the alignment film 14 is aligned (step 3). In the example shown, the coating is heated by the hot plate 30. That is, in the example shown, the heating source for the coating is the hot plate 30.

[0166] In the manufacturing method and the laminate of the present invention, the coefficient of thermal expansion of the substrate 12 is 10 × 10⁻⁶. -6 The temperature is below ℃ and the thickness is below 2 mm. Furthermore, in the manufacturing method of the laminate of the present invention, the heating of the coating film of the liquid crystal composition in step 3 is performed separately from the substrate 12.

[0167] By having this structure, the present invention achieves a laminate in which multiple optical components are formed, including a liquid crystal compound optical anisotropic layer, and obtains a laminate with high positional accuracy of the optical components and small deviation of the optical characteristics of the multiple optical components.

[0168] As shown in Patent Document 1, it is known that by forming multiple optical components on a single sheet and then cutting them into individual optical components, the productivity of optical components can be improved and the cost reduced.

[0169] However, according to the research of the inventors, in the case where multiple optical components are on a single sheet, problems such as low positional accuracy of the optical components and deviations in optical properties occur in the optical components having an optical anisotropy layer containing a liquid crystal compound.

[0170] The inventors discovered that the cause of the above-mentioned problem lies in the uneven temperature of the coating of the liquid crystal composition produced when heating is used to dry the coating of the liquid crystal composition and to orient the liquid crystal compound.

[0171] In other words, to form an optically anisotropic layer containing a liquid crystal compound, the coating of the liquid crystal composition needs to be heated to orient the liquid crystal compound within the optically anisotropic layer. During this heating, temperature inhomogeneity occurs in the coating of the liquid crystal composition, resulting in decreased positional accuracy of the optical components and deviations in the characteristics of multiple optical components.

[0172] Specifically, if temperature non-uniformity occurs in the coating of the liquid crystal composition that forms the optical anisotropic layer 16, the thermal expansion of the coating (substrate 12) varies depending on its position in the planar direction. Therefore, the positional relationship of the optical components 20 (liquid crystal alignment regions) changes due to the temperature non-uniformity. As a result, the positional accuracy of the optical components 20 in the laminate decreases.

[0173] Furthermore, if temperature inhomogeneity occurs in the coating of the liquid crystal composition that forms the optical anisotropy layer 16, the orientation states of each liquid crystal alignment region in the optical anisotropy layer 16 will differ due to the temperature inhomogeneity. As a result, the optical properties of multiple optical components will deviate.

[0174] In the following description, the coating of the liquid crystal composition will also be referred to simply as "coating".

[0175] Furthermore, unless otherwise specified, uneven temperature of the coating refers to uneven temperature in the surface direction.

[0176] The inventors further conducted repeated research and found that the coefficient of thermal expansion of the substrate 12, the thickness of the substrate 12, and the uneven heating based on the heating source are the main reasons for the uneven temperature of the coating film.

[0177] That is, when the coefficient of thermal expansion of the substrate 12 is large, heating causes the substrate 12 to warp. If the substrate 12 warps, the distance between the heating source, i.e., the hot plate 30 in the example, and the substrate 12, i.e., the coating, changes. As a result, depending on the state of warping of the substrate 12, uneven temperature distribution, i.e., temperature variation, occurs in the coating.

[0178] Furthermore, when the substrate 12 is thick, temperature unevenness occurs in the thickness direction. That is, the temperature of the substrate 12 is high on the heating source side and decreases as it moves away from the heating source in the thickness direction. If temperature unevenness occurs in the thickness direction of the substrate 12, the amount of thermal expansion in the planar direction is different in the thickness direction. As a result, in this case, the substrate 12 also warps, and similarly to the aforementioned coefficient of thermal expansion, temperature unevenness occurs in the coating film depending on the warping state of the substrate 12.

[0179] Furthermore, in the example shown, the coating is heated from the substrate 12 side via a hot plate 30. Here, the entire heating surface of the hot plate 30 is not necessarily flat, but has irregularities. If the substrate 12 (laminate) is placed on the hot plate 30 and heated, due to these irregularities, the substrate 12 will have portions that contact the hot plate 30 and portions that do not. Moreover, the distance between the non-contacting portions and the hot plate 30 varies depending on the irregularities. As a result, even if the temperature of the hot plate 30 is uniform across its entire surface, uneven heating will occur, resulting in temperature unevenness in the coating.

[0180] In conventional methods of manufacturing laminates, temperature non-uniformity is caused not only by each of the three factors individually, but also by the combined effect of the three factors, resulting in temperature non-uniformity (temperature distribution) in the coating film.

[0181] For example, if warping occurs in the substrate 12 due to the coefficient of thermal expansion, the temperature non-uniformity in the thickness direction of the substrate 12 increases due to the change in distance from the heating source caused by the warping. This temperature non-uniformity further leads to warping of the substrate 12, resulting in increased temperature non-uniformity of the coating. Furthermore, if temperature non-uniformity occurs in the substrate 12 due to uneven heating by the hot plate 30, the warping caused by the coefficient of thermal expansion and thickness of the substrate 12 further increases due to the temperature non-uniformity, resulting in even greater temperature non-uniformity.

[0182] In contrast, in this invention, the coefficient of thermal expansion of the substrate 12 is 10 × 10⁻⁶. -6 For heating the coating film in step 3, if the temperature is below ℃ and the thickness is below 2mm, the heating source shall be separated from the substrate 12.

[0183] By having this structure, the present invention enables the formation of a laminate in which the positional accuracy of each optical component is high and the deviation of the optical properties of the multiple optical components is small, in which multiple optical components are formed to form an optical anisotropic layer containing a liquid crystal compound.

[0184] If the coefficient of thermal expansion of substrate 12 exceeds 10×10 -6 If the temperature drops below a certain level, the warping of the substrate 12 caused by heating will increase, resulting in greater temperature unevenness of the coating, larger dimensional changes in areas where the temperature of the coating is higher than the surrounding average, changes in the drying process, and deterioration of film thickness distribution and optical properties.

[0185] The coefficient of thermal expansion of the substrate 12 is preferably 5×10⁻⁶. -6 / ℃ below.

[0186] The smaller the coefficient of thermal expansion of the substrate 12, the better, but it is usually 3 × 10⁻⁶. -6 / ℃ or above.

[0187] The coefficient of thermal expansion of the substrate 12 can be measured using a TMA (thermomechanical analysis device) and an optical thermal expansion measuring device. Examples of TMAs include the TMA / SS6100 (manufactured by Hitachi High-Tech Science Corporation) and the SS6100, while examples of optical thermal expansion measuring devices include the DIL806 and ODP868 (manufactured by TA Instruments Corporation).

[0188] Alternatively, if the coefficient of thermal expansion of the forming material is recorded in a catalog or the like, that value can be used as the coefficient of thermal expansion of the substrate 12.

[0189] If the thickness of the substrate 12 exceeds 2 mm, the warping of the substrate 12 caused by heating due to the thickness will increase, resulting in greater temperature unevenness of the coating, greater dimensional changes in areas where the temperature of the coating is higher than the surrounding average, changes in the drying process, and deterioration of film thickness distribution and optical properties.

[0190] The thickness of the substrate 12 is preferably less than 1.1 mm.

[0191] There is no particular limitation on the lower limit of the thickness of the substrate 12, but if the strength and stability of the laminate 10 are taken into account, the thickness of the substrate 12 is preferably 0.3 mm or more, and more preferably 0.5 mm or more.

[0192] As described above, there are no restrictions on the material used to form the substrate 12, as long as it meets the aforementioned coefficient of thermal expansion and thickness, and known sheet materials can be used.

[0193] Among them, glass is preferably exemplified as the substrate 12, and alkali-free glass is more preferably exemplified as the substrate 12.

[0194] Using glass as the substrate 12 offers advantages in terms of thermal expansion, ease of forming thickness, and rigidity. Specifically, rigidity refers to moderate weight and self-support. In particular, using alkali-free glass as the substrate 12 is advantageous due to its low defect rate. Alkali-free glass is widely used in semiconductor and display applications where low defects are common, thus enabling the use of these alkali-free glasses as the substrate 12.

[0195] Furthermore, when using alkali-free glass as the substrate 12, it is preferable to set the thickness to 1.2 mm or less.

[0196] In this invention, the coating is heated from the substrate 12 side while the substrate 12 is separated from the hot plate 30, which serves as a heating source. That is, in the example shown, the coating is heated from the substrate 12 side by the radiant heat of the hot plate 30.

[0197] As described above, when the substrate 12 is placed on the hot plate 30 (heating source), the unevenness of the hot plate 30 creates contact and non-contact portions between the substrate 12 and the hot plate 30, resulting in uneven temperature in the coating.

[0198] In contrast, by separating the substrate 12 from the hot plate 30 during the heating of the coating, uneven heating caused by the presence of contact and non-contact portions between the substrate 12 and the hot plate 30 can be prevented, thereby enabling uniform heating of the substrate 12, i.e., the coating.

[0199] In the manufacturing method of the present invention, as long as the substrate 12 and the heating source are separated by a single surface, the distance between the substrate 12 and the heating source is not limited. Here, the distance between the substrate 12 and the heating source is preferably 0.1 to 1 mm.

[0200] By setting the distance between the substrate 12 and the heating source to 0.1 mm or more, it is preferable to prevent the formation of contact portions between the substrate 12 and the heating source, and to suppress temperature unevenness of the hot plate itself by having the air layer act as a buffer.

[0201] By setting the distance between the substrate 12 and the heating source to less than 1 mm, it is preferred in terms of being able to perform heating based on the heating source with good efficiency and being able to accelerate the heating rate of the coating film.

[0202] The distance between the substrate 12 and the heating source is more preferably 0.1 to 0.8 mm, further preferably 0.2 to 0.6 mm, and especially preferably 0.3 to 0.4 mm.

[0203] There are no restrictions on the method of separating the substrate 12 from the heating source during the heating of the coating, and various known methods corresponding to the heating source can be used.

[0204] like Figure 7 As shown, when heating is performed using hot plate 30, such as Figure 9 As conceptually shown, a preferred method is to erect a plurality of pins 32 on the hot plate 30 and place a substrate 12 on the pins 32, thereby separating the substrate 12 from the hot plate 30.

[0205] There is no limitation on the spacing (interval) between the pins 32. As long as the spacing is appropriately set according to the rigidity of the substrate 12, it will not cause the substrate 12 to sag due to the weight of the laminate and thus avoid contact between the substrate 12 and the hot plate 30.

[0206] Here, the spacing between pins 32 is preferably 7 to 30 cm.

[0207] By setting the distance between the pins 32 to 7cm or more, it is preferable to prevent the reduction of the heating efficiency of the hot plate 30 due to an excessive number of pins 32 and to improve the efficiency of taking out each piece of glass.

[0208] By setting the distance between the pins 32 to less than 30cm, it is preferable to maintain a uniform distance between the substrate 12 and the hot plate 30, which can prevent the sag of the laminate caused by its own weight, and to maintain a uniform temperature distribution on the surface of the substrate 12.

[0209] The spacing between pins 32 is more preferably 7 to 15 cm, and even more preferably 8 to 12 cm.

[0210] The shape of the pin 32 used to separate the substrate 12 from the hot plate 30 is not particularly limited. Therefore, the shape of the pin 32 is not limited to the cone shape (pyramidal and conical) shown in the example.

[0211] However, considering factors such as the ability to be stably placed on the hot plate 30 and to reduce the contact area between the pin 32 and the substrate 12, the pin 32 is preferably a cone shape such as a pyramid or a cone as shown in the figure. Furthermore, the tip shape of the pin is more preferably spherical (curved) to prevent scratches.

[0212] Alternatively, infrared lamps can be used as a heating source. However, infrared lamps are hot near the optical axis and decrease in temperature as they move away from the optical axis. Therefore, the heating caused by the heating source results in uneven temperature distribution, which in turn leads to uneven temperature distribution within the coating film.

[0213] Furthermore, warm air can also be used as a heating source, but in heating based on warm air, it is difficult to heat the entire surface of the substrate 12, i.e., the coating, evenly.

[0214] Taking this into consideration, from the viewpoint of being able to uniformly heat the entire area of ​​the substrate 12, i.e., the surface direction of the coating, it is preferable to use a surface heating source such as a hot plate 30 for heating the coating.

[0215] Furthermore, as described above, in the manufacturing method of the present invention, the coating of the liquid crystal composition is heated from the substrate 12 side.

[0216] Therefore, it is possible to further reduce the temperature unevenness of the coating of the liquid crystal composition, and to prevent foreign matter from adhering to the coating of the liquid crystal composition due to the heating source located above.

[0217] Thus, after the drying of the coating and the orientation of the liquid crystal compound are completed, as... Figure 7 The second one from the left in the lower section shows that light is irradiated onto the coating film from the light source 50 to cure the coating film, i.e., the liquid crystal composition. As a result, an optical anisotropy layer 16 (step 4) is formed, which has unoriented non-oriented regions containing liquid crystal compounds and liquid crystal oriented regions containing liquid crystal compounds.

[0218] Thus, the following was accomplished. Figure 1 The stack 10 shown has 30 optical components 20 arranged at equal intervals in a 5×6 pattern.

[0219] As described above, the liquid crystal alignment region of the optical component 20, i.e., the optical anisotropic layer 16, is a liquid crystal lens with a liquid crystal alignment pattern. This liquid crystal alignment pattern has a concentric circle shape with a direction that changes from the inside to the outside while the orientation of the optical axis originating from the liquid crystal compound 40 changes continuously with rotation. That is, the laminate 10 in the example figure is a laminate in which 30 liquid crystal lenses are formed.

[0220] There are no restrictions on the light source 50 used for curing the coating, as long as a light source capable of emitting light of a wavelength that can cure (polymerize) the liquid crystal composition (liquid crystal compound) is appropriately selected according to the liquid crystal composition.

[0221] Typically, liquid crystal compounds with polymerizable groups polymerize under ultraviolet light. Therefore, an ultraviolet light source is usually used as the light source 50.

[0222] Furthermore, there is no limit to the amount (dosage) of ultraviolet radiation, as long as the amount of radiation is appropriately set according to the composition of the liquid crystal composition to properly cure the liquid crystal composition.

[0223] exist Figure 7 In the manufacturing method shown, as a preferred embodiment, the following steps are performed: Figure 7 As shown on the right side of the lower section, the alignment film 14 and the substrate 12 are peeled off from the optical anisotropic layer 16 (step 5). In addition, in this step 5, the substrate 12 can be peeled off from the optical anisotropic layer 16 and the alignment film 14.

[0224] The peeling of the substrate 12 is preferably performed simultaneously with the transport laminate 10.

[0225] In addition, such as Figure 7As shown on the left side of the upper section, the stripped substrate 12 is preferably cleaned again and reused in the manufacture of the laminate 10.

[0226] There are no limitations on the method of peeling the substrate 12 from the alignment film 14. Various known methods can be used, such as using an adhesive, using a jig such as a scraper inserted between the optical anisotropic layer 16 and the alignment film 14 or between the alignment film 14 and the substrate 12 to hold the alignment film 14 and / or the substrate 12, peeling by applying heat to utilize the difference in thermal expansion, and using a laser beam to create a peeling opportunity.

[0227] The optical anisotropic layer 16, from which the substrate 12 and alignment film 14 have been stripped, is finally cut into individual optical components 20, namely liquid crystal lenses.

[0228] The cutting location can be based on, for example, the boundary between the non-aligned region and the liquid crystal aligned region in the optical anisotropic layer 16. Alternatively, if the optical component 20 is a lens, the cutting can be based on the optical axis.

[0229] There are no restrictions on the cutting method; any known method, such as punching, guillotine cutting, or rotary cutting, can be used.

[0230] The manufacturing method of the laminate and the laminate of the present invention have been described above. However, the present invention is not limited thereto. Various improvements and modifications can be made without departing from the spirit of the present invention.

[0231] Example The features of the present invention will be further described in detail below with reference to specific embodiments.

[0232] The materials, reagents, dosages, quantities, ratios, processing contents, and processing steps shown in the following examples can be appropriately modified as long as they do not depart from the spirit of the present invention. Therefore, the scope of the present invention should not be limited by the specific examples shown below.

[0233] [Example 1] <Substrate> As the substrate, alkali-free glass with a size of 400×350mm and a thickness of 0.5mm was prepared.

[0234] The coefficient of thermal expansion of this alkali-free glass is 3×10⁻⁶. -6 / ℃.

[0235] <Formation of Orientation Film> The following oriented film forming coating liquid is applied to the surface of the substrate by slit coating.

[0236] The support with the coating liquid for forming the alignment film is dried on a hot plate at 60°C for 60 seconds to form an unexposed alignment film.

[0237] Coating solution for oriented film formation ―――――――――――――――――――――――――――――――― Raw material A for photoorientation, 1.00 parts by weight 16.00 parts by weight of water 42.00 parts by weight of butoxyethanol 42.00 parts by weight of propylene glycol monomethyl ether ―――――――――――――――――――――――――――――――― -Materials for Photoorientation A- [Chemical Formula 1] pass Figure 8 The exposure apparatus shown exposes the alignment film to form alignment film P-1.

[0238] As mentioned above, Figure 8 The exposure apparatus shown is for forming Figure 6 The exposure apparatus corresponding to the liquid crystal alignment pattern shown is a liquid crystal alignment pattern that changes as it rotates continuously in one direction from the inside to the outside in a concentric circle shape, with the orientation originating from the optical axis of the liquid crystal compound. Furthermore, in this liquid crystal alignment pattern, one period of the liquid crystal alignment pattern gradually shortens from the center of the concentric circles towards the outside.

[0239] Exposure was performed through a mask with an opening of 40×40mm. That is, the pattern alignment area (liquid crystal alignment area) is a rectangle with dimensions of 40×40mm for the optical components (see reference). Figure 6 ).

[0240] Furthermore, the substrate was moved with the optical components (pattern orientation areas) spaced 2 mm apart, and exposure was performed with 8 optical components on the long side and 7 on the short side of the substrate (see reference). Figure 10 ).

[0241] <Formation of anisotropic optical layers> As an optical anisotropic layer, a three-layer optical anisotropic layer structure is formed, consisting of the first to the third optical anisotropic layers.

[0242] Furthermore, among the optical anisotropy layers, the first and third optical anisotropy layers are designed as tilted optical anisotropy layers, where the bright and dark fringes in the cross-sectional SEM image obtained by observing the cross-section using a scanning electron microscope (SEM) are tilted relative to the normal of the interface. The second optical anisotropy layer, disposed between the first and third optical anisotropy layers, is designed as a non-tilted optical anisotropy layer, where the bright and dark fringes in the cross-sectional SEM image are aligned with the normal of the interface. Moreover, the tilt directions of the bright and dark fringes in the cross-sectional SEM image are different in the first and third optical anisotropy layers.

[0243] <<The Formation of the First Optical Anisotropic Layer>> Composition A-7 was prepared as a liquid crystal composition for forming an optical anisotropic layer.

[0244] (Composition A-7) ―――――――――――――――――――――――――――――――― Liquid crystal compound L-1 100.00 parts by weight Chiral reagent A 0.19 parts by weight Polymerization initiator (manufactured by BASF, Irgacure 907 (registered trademark)) 3.00 parts by weight Photosensitizer (manufactured by Nippon Kayaku Co., Ltd., KAYACURE DETX-S) 1.00 parts by weight Leveling agent T-1 0.08 parts by weight 2840.00 parts by weight of methyl ethyl ketone ―――――――――――――――――――――――――――――――― Liquid crystal compound L-1 [Chemical Formula 2] Chiral reagent A [Chemical Formula 3] Leveling agent T-1 [Chemical Formula 4] The first optical anisotropic layer is formed by multilayer coating of composition A-1 onto alignment film P-1. The process is repeated as follows: first, composition A-1 is coated onto the alignment film as the first layer, and after heating and cooling, it is cured with ultraviolet light to form a liquid crystal immobilization layer. Then, the second layer and thereafter are coated on top of the liquid crystal immobilization layer, and similarly, after heating and cooling, they are cured with ultraviolet light.

[0245] First, regarding the first layer, the following composition A-1 is coated onto the alignment film P-1. The coating is heated to 70°C on a hot plate, then cooled to 25°C, and then ultraviolet light with a wavelength of 365nm is emitted at 300mJ / cm² under a nitrogen atmosphere using a high-pressure mercury lamp. 2 The irradiation dose was applied to the coating, thereby immobilizing the orientation of the liquid crystal compound. At this point, the thickness of the first liquid crystal layer was 0.2 μm.

[0246] After the second layer, the liquid crystal layer is overlaid and then heated and cooled under the same conditions as described above, followed by ultraviolet curing to create a liquid crystal immobilization layer. This process of overlapping coatings is repeated until the total thickness reaches the desired film thickness, thus forming the first optical anisotropic layer.

[0247] <<The Formation of the Second Optical Anisotropic Layer>> As a liquid crystal composition for forming the second optical anisotropic layer, the following composition A-1 was prepared.

[0248] Composition A-1 ―――――――――――――――――――――――――――――――― Liquid crystal compound L-1 100.00 parts by weight Polymerization initiator (manufactured by BASF, Irgacure 907 (registered trademark)) 3.00 parts by weight Photosensitizer (manufactured by Nippon Kayaku Co., Ltd., KAYACURE DETX-S) 1.00 parts by weight Leveling agent T-1 0.08 parts by weight 2840.00 parts by weight of methyl ethyl ketone ―――――――――――――――――――――――――――――――― Using composition A-1, the film thickness was changed, and a second optical anisotropic layer was formed on the first optical anisotropic layer in the same manner as the first optical anisotropic layer.

[0249] <<The Formation of the Third Optical Anisotropic Layer>> As a liquid crystal composition for forming an optical anisotropic layer, the following composition A-8 was prepared.

[0250] (Composition A-8) ―――――――――――――――――――――――――――――――― Liquid crystal compound L-1 100.00 parts by weight Chiral reagent B 0.32 parts by weight Polymerization initiator (manufactured by BASF, Irgacure 907 (registered trademark)) 3.00 parts by weight Photosensitizer (manufactured by Nippon Kayaku Co., Ltd., KAYACURE DETX-S) 1.00 parts by weight Leveling agent T-1 0.08 parts by weight 2840.00 parts by weight of methyl ethyl ketone ―――――――――――――――――――――――――――――――― Chiral reagent B [Chemical Formula 5] Using composition A-8, a third optical anisotropic layer is formed on the second optical anisotropic layer in the same manner as the first optical anisotropic layer, thereby forming a three-layer optical anisotropic layer.

[0251] In the first and third optical anisotropic layers, the final Δn940 × thickness = Re(940) of the liquid crystal is 470nm, and in the second optical anisotropic layer, Δn940 × thickness (Re(940)) is 564nm.

[0252] Furthermore, polarized light microscopy confirmed that it became as follows. Figure 6 The concentric, periodic alignment surface is shown. Furthermore, in the liquid crystal alignment pattern of this first optical anisotropy layer, one period is very large at the center (the reciprocal of the period is considered 0), 9.0 μm at a distance of 1.0 mm from the center, 4.5 μm at a distance of 2.5 mm from the center, and 3.0 μm at a distance of 4.0 mm from the center, with the period decreasing towards the outward direction.

[0253] The first optical anisotropic layer has a rightward twist angle of 130° in the thickness direction. The second optical anisotropic layer has a thickness direction twist angle of 0°, and the third optical anisotropic layer has a leftward twist angle of 130° in the thickness direction. The twist directions of the first and third optical anisotropic layers are opposite.

[0254] Furthermore, in the cross-sectional SEM images, bright and dark fringes tilted relative to the normal to the lower interface of the optical anisotropy layer were observed in the first and third optical anisotropy layers, while bright and dark fringes extending along the normal were observed in the second optical anisotropy layer. In the first and third optical anisotropy layers, the tilt angle of the bright and dark fringes relative to the normal decreased from the center outwards, and the tilt directions of the bright and dark fringes relative to the normal were opposite in the first and third optical anisotropy layers. The pattern of the bright and dark fringes was observed to shorten from the center outwards in all three optical anisotropy layers.

[0255] [Example 2] The height of the pins for the coating of the heating (orientation of the liquid crystal compound) composition (liquid crystal composition) was set to 0.3 mm, and otherwise the laminate was made in the same manner as in Example 1.

[0256] [Example 3] The thickness of the substrate (alkali-free glass) was set to 1.1 mm, and otherwise the laminate was fabricated in the same manner as in Example 1.

[0257] [Example 4] The height of the pins for the coating used to heat the composition was set to 0.3 mm, and the thickness of the substrate was set to 1.1 mm. Otherwise, the laminate was made in the same manner as in Example 1.

[0258] [Example 5] The substrate was changed to borosilicate glass, but the laminate was fabricated in the same manner as in Example 4. The coefficient of thermal expansion of this substrate was 5 × 10⁻⁶. -6 / ℃.

[0259] [Example 6] The substrate was changed to quartz glass, but the laminate was fabricated in the same manner as in Example 4. The coefficient of thermal expansion of this substrate was 0.5 × 10⁻⁶. -6 / ℃.

[0260] [Example 7] The substrate was changed to aluminosilicate glass, and the laminate was fabricated in the same manner as in Example 4. The coefficient of thermal expansion of this substrate was 8.9 × 10⁻⁶. -6 / ℃.

[0261] [Example 8] The substrate was changed to soda glass, and the laminate was fabricated in the same manner as in Example 4. The coefficient of thermal expansion of this substrate was 9.2 × 10⁻⁶. -6 / ℃.

[0262] [Example 9] The thickness of the substrate was changed to 2 mm, and the laminate was otherwise fabricated in the same manner as in Example 8.

[0263] [Comparative Example 1] The laminate was fabricated in the same manner as in Example 8, except that no pins were used when coating the heated composition (liquid crystal composition) (the height of the pins was 0 mm).

[0264] [Comparative Example 2] The thickness of the substrate (sodium glass) was changed to 4 mm, and the laminate was otherwise fabricated in the same manner as in Example 8.

[0265] [Comparative Example 3] The substrate was changed to stainless steel (SUS340), and the laminate was fabricated in the same manner as in Example 9. The coefficient of thermal expansion of this substrate was 17 × 10⁻⁶. -6 / ℃.

[0266] [Comparative Example 4] The substrate was changed to polyethylene terephthalate (PET) film, and the laminate was fabricated in the same manner as in Example 9. The coefficient of thermal expansion of this substrate was 65 × 10⁻⁶. -6 / ℃.

[0267] [Comparative Example 5] The substrate was changed to a polycarbonate film, but the laminate was fabricated in the same manner as in Example 9. The coefficient of thermal expansion of this substrate was 70 × 10⁻⁶. -6 / ℃.

[0268] [evaluate] Regarding the fabricated laminate, the warpage of the substrate, in-plane temperature non-uniformity, thickness non-uniformity of the optical anisotropic layer, light leakage, and positional accuracy of the optical components were evaluated.

[0269] <Substrate Warpage> During heating, the warpage of the substrate was visually evaluated by observing it from the side of the hot plate.

[0270] The evaluation is as follows.

[0271] A: No warping B: There is warping (the lowest point of the warped substrate is higher than the center of the pin height). C: Warped (the lowest point of the warped substrate is near the center of the pin height) D: Large warpage (the substrate warps into contact with the hot plate or floats off the pin). <In-surface temperature non-uniformity> The temperature distribution in the surface of the substrate was measured by bringing thermocouples into contact.

[0272] If the temperature distribution within the surface (maximum temperature - minimum temperature [°C]) is within 4°C, it is good; if it is within 10°C, it is within the allowable range; if it exceeds 10°C, it is considered outside the allowable range (unacceptable).

[0273] <Uneven thickness> The thickness inhomogeneity of the optical anisotropic layer was measured using an interferometer. Measurements were performed comprehensively at 10 mm intervals.

[0274] The evaluation is as follows.

[0275] A: The thickness non-uniformity relative to the average film thickness is less than ±2%. B: The thickness non-uniformity relative to the average film thickness is greater than ±2 and less than 4%. C: The thickness non-uniformity relative to the average film thickness is above 4%. <Light Leak> Regarding the aforementioned 40×40mm optical components, the evaluation device was assembled as follows: collimated right-handed circularly polarized light with a wavelength of 532nm was incident on the optical anisotropic layer at an incident angle of 30° (the angle relative to the normal direction of the surface of the optical anisotropic layer), and the non-diffracted light was incident perpendicularly on the detector through a left-handed circularly polarizer (a polarizer that allows left-handed circularly polarized light to pass through).

[0276] The ratio (%) of the intensity of the emitted light without diffraction to the intensity of the incident light [(intensity of emitted light without diffraction / intensity of incident light) × 100] was measured as the magnitude of light leakage. For 56 samples of the sheet (8 columns on the long side and 7 columns on the short side), measurements were taken at 4 locations for each optical component.

[0277] The evaluation is as follows.

[0278] A: The maximum light leakage is below 2%. B: The maximum light leakage is greater than 2% and less than 5%. C: The maximum light leakage is greater than 5%. <Position accuracy of optical components> In this example, such as Figure 10 As conceptually shown, on a 400×350mm substrate, optical components are formed by 8 in the long side and 7 in the horizontal side, spaced 2mm apart, in a vertical arrangement of 8 and 7 in the short side.

[0279] Use adhesive sheets to peel off the optical anisotropic layer, such as Figure 10As shown, in the arrangement of the optical components, the optical component A in the upper left corner of the figure is used as a reference. The distance between the lower right corner (black circle) of the reference and the lower right corner (black circle) of the 7th optical component B on the long side, as well as the distance between the lower right corner (black circle) of the reference and the 7th optical component C on the short side, are measured.

[0280] In the design value, the distance between the two distances is 252 mm. The positional accuracy of the optical component was evaluated by comparing the larger of the two measured distances with the design value. The positional accuracy was measured using a length measuring machine (KEYENCE CORPORATION IM-8000 image dimension measuring instrument).

[0281] The evaluation is as follows.

[0282] A: The distance difference is less than 100μm B: The distance difference is greater than 100μm and less than 200μm C: The distance difference is greater than 200μm and less than 500μm D: Distance difference greater than 500μm The results are shown in the table below.

[0283] [Table 1]

[0284] As shown in the table above, the laminate of the present invention is superior to the comparative example in terms of substrate warpage, thickness inhomogeneity, and positional accuracy.

[0285] Furthermore, as mentioned above, in-plane temperature non-uniformity is acceptable as long as it is within 4°C, and is outside the allowable range if it exceeds 10°C. However, the comparative examples were all unqualified, while the laminates of the present invention are all good.

[0286] Based on the above results, the present invention is effective.

[0287] Industrial availability It can be preferably used in the manufacture of optical components used in various optical devices.

[0288] Symbol Explanation 10-Laminated body, 12-Substrate, 14-Orientation film, 14a-Unexposed orientation film, 16-Optical anisotropic layer, 20-Optical component, 30-Hot plate, 32-Pin, 40-Liquid crystal compound, 52, 54-Coating unit, 80-Exposure device, 82-Laser, 84-Light source, 86-Polarization beam splitter, 90A, 90B-Mirror, 92-Lens, 94-Beam splitter, 96-λ / 4 plate.

Claims

1. A method for manufacturing a laminate, comprising: Step 1: Forming an alignment film with non-aligned regions and multiple patterned alignment regions on a substrate; Step 2: A coating film is formed by coating the alignment film with a composition containing a liquid crystal compound having polymerizable groups; Step 3: Heating the coating from the substrate side to orient the liquid crystal compound in the patterned alignment region; and Step 4 involves exposing the coating film to form an optically anisotropic layer having unoriented non-aligned regions of the liquid crystal compound and multiple oriented liquid crystal regions of the liquid crystal compound. The coefficient of thermal expansion of the substrate is 10 × 10⁻⁶. -6 / ℃ below, The thickness of the substrate is less than 2 mm. In step 3, the heating source of the coating film is separated from the substrate while the coating film is heated.

2. The method for manufacturing a laminate according to claim 1, wherein, In step 3, the distance between the heating source of the coating and the substrate is 0.1 to 1 mm.

3. The method for manufacturing a laminate according to claim 1 or 2, wherein, The heating source of the coating in step 3 is separated from the substrate by a plurality of pins disposed on the heating source.

4. The method for manufacturing a laminate according to claim 3, wherein, The plurality of pins are arranged apart from each other, with a spacing of 7 to 30 cm between them.

5. The method for manufacturing a laminate according to claim 1 or 2, wherein, After step 4, the following are provided: Step 5: Peel off the alignment film and the substrate from the optical anisotropy layer, or peel off the substrate from the alignment film.

6. A laminated body having: Substrate; An orientation film having non-oriented regions and multiple patterned orientation regions; and The optical anisotropic layer includes unoriented, non-aligned regions of the liquid crystal compound and multiple oriented liquid crystal regions of the liquid crystal compound. The coefficient of thermal expansion of the substrate is 10 × 10⁻⁶. -6 / ℃ below, The thickness of the substrate is less than 2 mm.

7. The laminate according to claim 6, wherein, The distance between the plurality of liquid crystal alignment regions is 0.5 to 10 mm.

8. The laminate according to claim 6 or 7, wherein, The liquid crystal alignment region of the optical anisotropy layer has a liquid crystal alignment pattern that changes while continuously rotating in at least one in-plane direction, originating from the optical axis of the liquid crystal compound, and... When the length of a 180° in-plane rotation of the orientation of the optical axis originating from the liquid crystal compound is defined as one cycle, there are regions in the plane having different lengths of the one cycle in the liquid crystal alignment pattern.

9. The laminate according to claim 6 or 7, wherein, The substrate is alkali-free glass with a thickness of less than 1.2 mm.

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