Display medium, method for manufacturing the same, and display article

Abstract

The present invention provides a display medium, which comprises a substrate and a display layer arranged on the substrate, wherein the display layer comprises a plurality of small layers divided by cracks, and when observed from the thickness direction, the plurality of small layers are arranged in two or more directions.

Description

Technical Field

[0001] The present invention relates to a display medium and a method for manufacturing the same, and a display article having the display medium. Background Art

[0002] From the perspective of diversification of the display method of an object, a display method using polarized light is sometimes used. In order to realize such a display method using polarized light, liquid crystal materials are sometimes used in the past. In addition, liquid crystal materials are sometimes used for the purpose of identifying authenticity. As examples of these technologies, the technologies described in Patent Documents 1 to 3 can be cited.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-105327;

[0006] Patent Document 2: Japanese Patent Application Publication No. 2014-174471;

[0007] Patent document 3: Japanese Patent No. 4630465. Summary of the invention

[0008] Problem that the invention aims to solve

[0009] Although display media utilizing polarized light are generally difficult to counterfeit, there is a need to further increase the difficulty of counterfeiting.

[0010] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a display medium and a method for manufacturing the display medium that improve the difficulty of counterfeiting, and a display article having the display medium.

[0011] Solutions for solving problems

[0012] The present inventors have conducted intensive research to solve the above problems and have found that the above problems can be solved by providing a small piece layer arranged with high regularity in the display layer, thereby completing the present invention.

[0013] That is, the present invention includes the following contents.

[0014] [1] A display medium comprising a substrate and a display layer provided on the substrate,

[0015] The display layer comprises a plurality of small layers divided by cracks.

[0016] When viewed from the thickness direction, the plurality of small sheet layers are arranged in two or more directions.

[0017] [2] The display medium according to [1], wherein the thickness of the small piece layer is 10 μm or less.

[0018] [3] The display medium according to [1] or [2], wherein the small sheet layer is formed of a cured product of a liquid crystal composition.

[0019] [4] A display medium according to any one of [1] to [3], wherein the in-plane retardation of the above-mentioned small layer at a measured wavelength of 550nm is greater than "{(2n1+1) / 4}×550nm-30nm" and less than "{(2n1+1) / 4}×550nm+30nm" (wherein n1 represents an integer greater than 0).

[0020] [5] A display medium according to any one of [1] to [3], wherein the in-plane retardation of the above-mentioned small layer at a measured wavelength of 550nm is greater than "{(2n2+1) / 2}×550nm-30nm" and less than "{(2n2+1) / 2}×550nm+30nm" (wherein n2 represents an integer greater than 0).

[0021] [6] The display medium according to any one of [1] to [5], wherein the small sheet layer is one or more selected from a positive A plate, a positive C plate, an inclined O plate, and an inclined hybrid orientation plate.

[0022] [7] The display medium according to any one of [1] to [3], wherein the small sheet layer has a structure capable of reflecting a rotation direction D D The circularly polarized light is rotated in the direction D D The wavelength range in which circularly polarized light of opposite rotation direction is transmitted is shown.

[0023] [8] The display medium according to any one of [1] to [7], wherein the substrate has a selective reflection layer, and the selective reflection layer has a structure capable of reflecting light in a rotation direction D S The circularly polarized light is rotated in the direction D S Circularly polarized light of opposite rotation direction is transmitted through the substrate reflection range.

[0024] [9] The display medium according to [7], wherein the substrate has a selective reflection layer, and the selective reflection layer has a function of reflecting light in a rotation direction D S The circularly polarized light is rotated in the direction D S The reflection range of the substrate through which circularly polarized light of the opposite rotation direction is transmitted.

[0025] The wavelength width of the substrate reflection range is wider than the wavelength width of the display wavelength range.

[0026]

[10] The display medium according to [8] or [9], wherein the wavelength width of the reflection range of the substrate is greater than or equal to 70 nm.

[0027]

[11] The display medium according to any one of [1] to

[10] , wherein the display medium has a plurality of the display layers.

[0028]

[12] The display medium according to any one of [1] to

[11] , wherein the shape of the small piece layer as viewed in the thickness direction is rectangular.

[0029]

[13] The display medium according to any one of [1] to

[12] , wherein the width of the small piece layer as viewed in the thickness direction is 100 μm or less.

[0030]

[14] The display medium according to any one of [1] to

[13] , wherein the substrate has a colored layer.

[0031]

[15] The display medium according to any one of [1] to

[14] , wherein the display medium has an adhesive layer between the substrate and the display layer.

[0032]

[16] A method for manufacturing a display medium, which is the method for manufacturing a display medium according to any one of [1] to

[15] , comprising the following steps:

[0033] A step of preparing a raw material member having a temporary support and a transfer material layer, wherein the transfer material layer is formed on the temporary support and includes the small piece layer;

[0034] The step of forming an adhesive layer having the same shape as the display layer when viewed from the thickness direction on the substrate;

[0035] A step of laminating the transfer material layer and the adhesive layer;

[0036] A step of peeling off the temporary support.

[0037]

[17] A display article comprising a base article and the display medium described in any one of [1] to

[15] disposed on the base article.

[0038] Effects of the Invention

[0039] According to the present invention, it is possible to provide a display medium that increases the difficulty of counterfeiting, a method for manufacturing the display medium, and a display article having the display medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1This is a schematic plan view of the display medium according to the first embodiment of the present invention as viewed from the thickness direction.

[0041] Figure 2 The display medium of the first embodiment of the present invention is schematically shown as follows: Figure 1 The cross-sectional view is a cross-sectional view taken along the II-II plane.

[0042] Figure 3 The display medium of the first embodiment of the present invention is schematically and enlargedly shown. Figure 1 An enlarged top view of portion III is shown.

[0043] Figure 4 The display medium of the first embodiment of the present invention is schematically shown as follows: Figure 3 The cross-sectional view is a cross-sectional view taken along the IV-IV plane.

[0044] Figure 5 This is a schematic plan view of a raw material member prepared in the method for manufacturing a display medium according to the first embodiment of the present invention, as viewed from the thickness direction.

[0045] Figure 6 The present invention schematically shows the use of the raw material components prepared in the method for manufacturing the display medium of the first embodiment of the present invention. Figure 5 The cross-sectional view is a cross-sectional view taken along the VI-VI plane.

[0046] Figure 7 The figure schematically shows in an enlarged manner the raw material components prepared in the method for manufacturing the display medium according to the first embodiment of the present invention. Figure 5 An enlarged top view of portion VII is shown.

[0047] Figure 8 The present invention schematically shows the use of the raw material components prepared in the method for manufacturing the display medium of the first embodiment of the present invention. Figure 7 The cross-sectional view is a cross-sectional view taken along the VIII-VIII plane shown.

[0048] Fig. 9 This is a perspective view schematically showing an example of a processing tool that can be used in the method for manufacturing a raw material member in the method for manufacturing a display medium according to the first embodiment of the present invention.

[0049] Fig.10 It is schematically shown Fig. 9 A perspective view of the processing tool shown.

[0050] Fig.11 It is a schematic diagram showing Fig.10 A top view of the processing tool in a state where it is cut and unfolded along the XI-XI line.

[0051] Fig.12 This is a partial cross-sectional view schematically showing a cross section of a part of the vicinity of the surface of the processing tool cut by a plane perpendicular to the direction in which the protrusions extend.

[0052] Fig.13 This is a perspective view schematically showing an example of a processing tool that can be used in the method for manufacturing a raw material member in the method for manufacturing a display medium according to the first embodiment of the present invention.

[0053] Fig.14 It is schematically shown Fig.13 A perspective view of the processing tool shown.

[0054] Fig.15 It is a schematic diagram showing Fig.14 A top view of the processing tool in a state where it is cut off along line XV-XV and unfolded.

[0055] Fig.16 This is a schematic plan view of the display medium according to the second embodiment of the present invention as viewed from the thickness direction.

[0056] Fig.17 The display medium of the second embodiment of the present invention is schematically shown as follows: Fig.16 A sectional view of a section cut along the XVII-XVII plane is shown.

[0057] Fig.18 FIG. 1 is a schematic enlarged view showing a display medium according to a second embodiment of the present invention. Fig.16 An enlarged top view of portion XVIII is shown.

[0058] Fig.19 This is a schematic plan view of a display medium according to a third embodiment of the present invention as viewed from the thickness direction.

[0059] Fig. 20 The display medium of the third embodiment of the present invention is schematically shown as follows: Fig.19 The cross-sectional view is a cross-sectional view of a section cut along the XX-XX plane shown.

[0060] Fig.21 FIG. 1 is a schematic enlarged view showing a display medium according to a third embodiment of the present invention. Fig.19 An enlarged top view of portion XXI is shown.

[0061] Fig. 22 101 is a top view schematically showing the display medium manufactured in Example 101.

[0062] Fig.23 is a cross-sectional view schematically showing the display medium manufactured in Example 101. DETAILED DESCRIPTION

[0063] The present invention will be described in detail below with reference to the embodiments and examples. However, the present invention is not limited to the embodiments and examples described below, and can be implemented with any modifications without departing from the scope of the claims and their equivalents.

[0064] In the following description, unless otherwise specified, the in-plane direction refers to a direction perpendicular to the thickness direction.

[0065] In the following description, unless otherwise specified, the in-plane retardation Re of the layer is a value represented by Re=(nx-ny)×d. Here, nx represents the refractive index in the direction perpendicular to the thickness direction of the layer (in-plane direction) providing the maximum refractive index. Ny represents the refractive index in the direction orthogonal to the direction of nx in the above-mentioned in-plane direction. Nz represents the refractive index in the thickness direction. D represents the thickness of the layer. Unless otherwise specified, the measurement wavelength is 550nm.

[0066] In the following description, “circularly polarized light” also includes elliptically polarized light as long as the effects of the present invention are not significantly impaired.

[0067] In the following description, unless otherwise specified, the directions of elements are "parallel", "perpendicular" and "orthogonal" and may include errors within the range of, for example, ±4°, preferably ±3°, and more preferably ±1°, within the range that does not impair the effects of the present invention.

[0068] In the following description, unless otherwise specified, the “visible wavelength range” refers to a wavelength range of 400 nm to 780 nm.

[0069] In the following description, "long strip" refers to a shape having a length of 5 times or more relative to the width, preferably 10 times or more, and specifically refers to a shape of a film having a length that can be wound into a roll for storage or transportation. The upper limit of the length is not particularly limited, for example, it can be 100,000 times or less relative to the width.

[0070] [1. Display Medium of First Embodiment]

[0071] Figure 1 1 is a schematic plan view of the display medium 10 according to the first embodiment of the present invention as viewed from the thickness direction. Figure 2 The display medium 10 of the first embodiment of the present invention is schematically shown. Figure 1 The cross-sectional view is a cross-sectional view taken along the II-II plane.

[0072] like Figure 1 and Figure 2As shown, the display medium 10 according to the first embodiment of the present invention includes a substrate 100 and a display layer 200 provided on the substrate 100 .

[0073] [1.1. Base material 100]

[0074] The substrate 100 is a member capable of supporting the display layer 200, and generally has a supporting layer 110. There is no particular limitation on the material forming the supporting layer, and organic materials, inorganic materials, and composite materials of a combination thereof can be used. Specific examples of the material of the supporting layer include resin, paper, cloth, leather, metal, alloy, glass, etc. Among them, resin is preferred from the perspective of easy manufacture of the display medium 10 and excellent flexibility.

[0075] As resin, thermoplastic resin is usually used. The thermoplastic resin can contain polymer and any component as needed. As polymer, for example, polycarbonate, polyethersulfone, polyethylene terephthalate, polyimide, polymethyl methacrylate, polysulfone, polyarylate, polyethylene, polyphenylene oxide, polystyrene, polyvinyl chloride, cellulose diacetate, cellulose triacetate and polymer containing alicyclic structure can be cited. In addition, polymer can be used alone or in combination of two or more in any proportion. Among them, from the viewpoint of transparency, low hygroscopicity, dimensional stability and processability, polymer containing alicyclic structure is preferred. Polymer containing alicyclic structure is a polymer having alicyclic structure in the main chain and / or side chain, for example, polymers described in Japanese Patent Publication No. 2007-057971 can be used.

[0076] There is no limitation on the in-plane retardation of the support layer 110. In this embodiment, an example of using an optically isotropic support layer 110 with small in-plane retardation is shown for explanation. The in-plane retardation of the optically isotropic support layer 110 at a measurement wavelength of 550 nm is preferably 0 to 20 nm, more preferably 0 to 10 nm, and particularly preferably 0 to 5 nm.

[0077] The substrate 100 may be a transparent member that transmits light or a non-transparent member that does not transmit light. In this embodiment, a transparent substrate 100 that transmits light is shown for description.

[0078] The shape of the substrate 100 is not limited. The substrate 100 may be in the form of a plate, a sheet, a film, or the like. Among them, a film-shaped substrate 100 is preferred from the viewpoint of making the display medium 10 thinner. In particular, when a long film is used as the substrate 100, the display medium 10 can be efficiently manufactured using a roll-to-roll method.

[0079] The thickness of the substrate 100 is not particularly limited, but is preferably 5 μm or more, more preferably 10 μm or more, particularly preferably 20 μm or more, and is preferably 1 mm or less, more preferably 500 μm or less, particularly preferably 200 μm or less.

[0080] [1.2. Display layer 200]

[0081] The display layer 200 is directly or indirectly disposed on the substrate 100. The display layer 200 is "directly" disposed on the substrate 100, which means that there are no other layers between the substrate 100 and the display layer 200. In addition, the display layer 200 is "indirectly" disposed on the substrate 100, which means that there are other layers between the substrate 100 and the display layer 200.

[0082] The display layer 200 may be provided on the entire surface 100U of the substrate 100 , but is generally provided on a portion of the surface 100U of the substrate 100 .

[0083] For example, the display layer 200 may be disposed in a region of the surface 100U having a specific shape when viewed from the thickness direction. In this case, the display layer 200 can have a specific shape when viewed from the thickness direction. Therefore, an observer who observes the display medium 10 can observe the shape.

[0084] In addition, for example, the display layer 200 may be provided in an area other than the area having a specific shape when viewed from the thickness direction of the surface 100U. In this case, the area where the display layer 200 is not provided can have a specific shape when viewed from the thickness direction. Therefore, an observer who observes the display medium 10 can observe the shape.

[0085] Therefore, in any case, the design of the display medium 10 can be improved.

[0086] As the above-mentioned specific shape, for example, characters, numbers, symbols, pictures, etc. can be cited. However, the specific shape is not limited to the above-mentioned examples. Figure 1 As shown in the figure, an example in which the display layer 200 having a shape of a letter “T” when viewed from the thickness direction is provided will be described.

[0087] Figure 3 The display medium 10 according to the first embodiment of the present invention is schematically and enlargedly shown. Figure 1 The enlarged top view of part III is shown. In addition, Figure 4 The display medium 10 of the first embodiment of the present invention is schematically shown. Figure 3 The cross-sectional view is a cross-sectional view taken along the IV-IV plane.

[0088] like Figure 3 and Figure 4As shown, the display layer 200 includes a plurality of small layers 220 divided by cracks 210. Specifically, each small layer 220 is disposed at a different position on the surface 100U of the substrate 100, and the small layers 220 are divided from each other by the cracks 210 formed in the entire thickness of the display layer 200. Moreover, a group formed by the collection of these plurality of small layers 220 forms one display layer 200.

[0089] When observed from the thickness direction, the small pieces 220 included in a display layer 200 are arranged in two or more directions. In the following description, the direction in which such small pieces 220 are arranged is sometimes referred to as the "arrangement direction". These arrangement directions are all directions perpendicular to the thickness direction, and therefore can be parallel to the layer plane of the display layer. Therefore, usually when drawing a line segment connecting the small pieces 220 adjacent to each other across the crack 210, the line segment is parallel to any one of the above-mentioned two or more arrangement directions. The number of arrangement directions is usually more than 2, preferably less than 4, and more preferably less than 3. For example, in the case where the shape of the small piece layer 220 observed from the thickness direction is an equilateral triangle, the number of arrangement directions of the small piece layer 220 included in a display layer 200 can be 3. In addition, for example, in the case where the shape of the small piece layer 220 observed from the thickness direction is a rectangle, the number of arrangement directions of the small piece layer 220 included in a display layer 200 can be 2. Furthermore, for example, when the shape of the small piece layer 220 viewed from the thickness direction is a regular hexagon, the number of arrangement directions of the small piece layer 220 included in one display layer 200 may be three.

[0090] In the past, it was difficult to form a display layer as a collection of small layers arranged with high regularity. For example, when a coating containing pigments corresponding to the small layers is applied to a substrate to form a display layer, the pigments contained in the obtained display layer are randomly arranged, and high regularity cannot be achieved. The display layer 200 of the display medium 10 of this embodiment is formed by small layers 220, and the small layers 220 are arranged with high regularity such as being arranged in two or more directions, so it is difficult to manufacture in the prior art. Therefore, it is possible to increase the difficulty of counterfeiting the display medium 10.

[0091] The angle between the arrangement directions of the small pieces of the layer 220 included in a display layer 200 is usually 5° or more, more preferably 10° or more, further preferably 30° or more, particularly preferably 40° or more, and usually 90° or less. Figure 3 As shown, the example in which the small piece layer 220 included in the display layer 200 is arranged in a first arrangement direction X perpendicular to the thickness direction and a second arrangement direction Y perpendicular to both the thickness direction and the arrangement direction X will be described.

[0092] The small pieces 220 included in one display layer 200 preferably have the same shape when viewed from the thickness direction. Since the display layer 200 formed by a group of small pieces 220 having the same shape is particularly difficult to manufacture, it can effectively increase the difficulty of counterfeiting the display medium 100.

[0093] The shape of each small piece layer 220 observed from the thickness direction is not particularly limited. As preferred examples, polygons such as triangles, quadrilaterals, and hexagons can be cited. Among them, regular triangles, quadrilaterals, and regular hexagons are preferred, quadrilaterals are more preferred, parallelograms are further preferred, rectangles such as squares and rectangles are further preferred, and squares are particularly preferred.

[0094] The width of each small piece layer 220 observed from the thickness direction is preferably within a specific range. Specifically, the width of the small piece layer 220 is preferably less than 150 μm, more preferably less than 125 μm, further preferably less than 100 μm, and particularly preferably less than 80 μm. There is no particular restriction on the lower limit, which is usually greater than 0 μm, and preferably greater than 10 μm. The width of the small piece layer 220 refers to the longest distance between multiple parallel lines drawn in a manner that connects to the outline of the small piece layer 220. Such a small piece layer 220 is difficult to see with the naked eye, and therefore can effectively increase the difficulty of counterfeiting the display medium 10.

[0095] Since the small pieces 220 are arranged in two or more arrangement directions, the cracks 210 that divide the small pieces 220 usually include notches 211 and 212 extending in two or more directions. Preferably, when viewed from the thickness direction, the cracks 210 include a plurality of notches 211 extending linearly in a certain direction and a plurality of notches 212 extending linearly in a direction different from the direction. Furthermore, it is more preferred that the notches 211 and 212 each extend linearly continuously over the entire display layer 200. When such notches 211 and 212 are used, the small pieces 220 can be manufactured particularly smoothly.

[0096] In the case where the cuts 211 and 212 extend continuously and linearly over the entire display layer 200, the cracks 210 can be arranged in a grid shape as a whole. Moreover, the small layers 220 divided by the cracks 210 can be arranged along the direction in which the cuts 211 and 212 extend. Figure 3 The example of a grid-like crack 210 including a first group of notches 211 and a second group of notches 212 dividing a rectangular small layer 220 is used for illustration, wherein the first group of notches 211 extends continuously and linearly along a first arrangement direction X on the entire display layer 200, and the second group of notches 212 extends continuously and linearly along a second arrangement direction Y on the entire display layer 200.

[0097] It is preferable that the intervals between the scores 211 and 212 extending in the same direction in the cracks 210 formed in one display layer 200 are substantially equal. Therefore, in the example shown in this embodiment, it is preferable that the interval P between the scores 211 extending in the arrangement direction X is 1 / 2. 211 In addition, it is preferred that the interval P between the notches 212 extending along the arrangement direction Y is 212 Here, the fact that a certain interval (first interval) and another interval (second interval) between the notches are substantially the same means that the second interval is greater than 90% and less than 110% of the first interval. In this case, the shape of each small piece layer 220 observed in the thickness direction can usually be made the same, so the difficulty of counterfeiting the display medium 10 can be effectively increased.

[0098] It is preferred that the intervals between the scores 211 and 212 extending in different directions included in the cracks 210 formed in one display layer 200 are substantially the same. Therefore, in the example shown in this embodiment, it is preferred that the interval P between the scores 211 extending in the arrangement direction X is 1 / 2. 211 , and the interval P between the notches 212 extending along the arrangement direction Y 212 In this case, the regularity of the arrangement of each small piece layer 220 when viewed in the thickness direction can generally be improved, and thus the difficulty of counterfeiting the display medium 10 can be effectively increased.

[0099] When the grid-like cracks 210 divide the rectangular small pieces 220 as in the example shown in this embodiment, the interval P between the above-mentioned notches 211 is 211 and the interval P between the notches 212 212 The length of the side corresponding to the small piece layer 220 may be consistent. 211 and P 212 When the length of the side of the small piece layer 220 is not consistent, these intervals P 211 and P 212 It can also be related to the size of the small piece layer 220. Therefore, the preferred spacing P 211 and P 212 It is set according to the size of the small piece layer 220 .

[0100] Usually the interval P 211 and P 212 The smaller the size of the small piece layer 220, the smaller the size of the small piece layer 220. In addition, the smaller the size of the small piece layer 220, the more difficult it is to see with the naked eye, so the difficulty of counterfeiting the display medium 10 can be increased. Therefore, from the perspective of increasing the difficulty of counterfeiting the display medium 10, it is preferred that the interval P is 211 and P 212In a specific small range. Specifically, the interval P 211 and P 212 Each is preferably 150 μm or less, more preferably 125 μm or less, further preferably 115 μm or less, and particularly preferably 100 μm or less. The lower limit is not particularly limited, but is usually greater than 0 μm, and preferably 10 μm or more.

[0101] The thickness of the small piece layer 220 is preferably 0.1 μm or more, more preferably 1 μm or more, further preferably 2 μm or more, preferably 10 μm or less, more preferably 8 μm or less, further preferably 6 μm or less, and particularly preferably 5 μm or less. The thickness of the small piece layer 220 included in one display layer 200 may be different, but is preferably the same. When the small piece layer 220 is thin, the size of the small piece layer 220 observed from the thickness direction can be reduced, so the difficulty of counterfeiting the display medium 10 can be effectively increased.

[0102] The small layer 220 may also have in-plane retardation. The small layer 220 having in-plane retardation and the display layer 200 including the small layer can function as a phase difference plate, so the polarization state of the transmitted light can be adjusted. Therefore, by effectively utilizing the adjustment of the polarization state based on the small layer 220 and the display layer 200, the display medium 10 can realize multiple display modes.

[0103] For example, the small sheet layer 220 may have an in-plane retardation capable of functioning as a quarter wave plate. The specific in-plane retardation of the small sheet layer 220 functioning as a quarter wave plate is preferably "{(2n1+1) / 4}×550nm-30nm" or more, more preferably "{(2n1+1) / 4}×550nm-20nm" or more, particularly preferably "{(2n1+1) / 4}×550nm-10nm" or more, preferably "{(2n1+1) / 4}×550nm+30nm" or less, more preferably "{(2n1+1) / 4}×550nm+20nm" or less, particularly preferably "{(2n1+1) / 4}×550nm+10nm" or less when the measurement wavelength is 550nm. Here, n1 represents an integer greater than 0. The small piece layer 220 having the above-mentioned in-plane retardation Re when the measurement wavelength is 550 nm can generally function as a quarter wave plate in a wide range of the visible wavelength range. Therefore, the polarization state of the transmitted light of a wide range of colors can be appropriately adjusted by the small piece layer 220 and the display layer 200 including the small piece layer. Therefore, the degree of freedom of the color of the display layer 220 can be increased, so that a display medium 10 with high design properties can be realized.

[0104] For example, the small sheet layer 220 may have an in-plane retardation capable of functioning as a half-wave plate. The specific in-plane retardation of the small sheet layer 220 capable of functioning as a half-wave plate is preferably "{(2n2+1) / 2}×550nm-30nm" or more, more preferably "{(2n2+1) / 2}×550nm-20nm" or more, particularly preferably "{(2n2+1) / 2}×550nm-10nm" or more, preferably "{(2n2+1) / 2}×550nm+30nm" or less, more preferably "{(2n2+1) / 2}×550nm+20nm" or less, particularly preferably "{(2n2+1) / 2}×550nm+10nm" or less when the measured wavelength is 550nm. Here, n2 represents an integer greater than 0. The small piece layer 220 having the above-mentioned in-plane retardation Re when the measurement wavelength is 550 nm can generally function as a half-wave plate in a wide range of the visible wavelength range. Therefore, the polarization state of the transmitted light of a wide range of colors can be appropriately adjusted by the small piece layer 220 and the display layer 200 including the small piece layer. Therefore, the degree of freedom of the color of the display layer 220 can be increased, so that a display medium 10 with high design properties can be realized.

[0105] The in-plane retardation of the small piece layers 220 included in one display layer 200 may be different, but is preferably the same.

[0106] There is no particular restriction on the wavelength dispersion of the small piece layer 220. Therefore, the small piece layer 220 may have positive wavelength dispersion or inverse wavelength dispersion. Positive wavelength dispersion means that the in-plane delay Re(450) and Re(550) satisfy the following formula (R1) when the measured wavelength is 450nm and 550nm. For the small piece layer 220 with positive wavelength dispersion, generally, the longer the measured wavelength, the smaller the in-plane delay. In addition, inverse wavelength dispersion means that the in-plane delay Re(450) and Re(550) satisfy the following formula (R2) when the measured wavelength is 450nm and 550nm. For the small piece layer 220 with inverse wavelength dispersion, generally, the longer the measured wavelength, the larger the in-plane delay.

[0107] Re(450)>Re(550) (R1)

[0108] Re(450)<Re(550) (R2)

[0109] The small piece layer 220 can adjust the transmitted light in the visible wavelength range to different polarization states according to the wavelength dispersion of the small piece layer 220. For example, when the small piece layer 220 that can function as a 1 / 4 wave plate at a certain wavelength has an inverse wavelength dispersion, the small piece layer 220 can provide a 1 / 4 wavelength in-plane delay to the transmitted light in the entire visible wavelength range. On the other hand, when the small piece layer 220 that can function as a 1 / 4 wave plate at a certain wavelength has a positive wavelength dispersion, the small piece layer 220 can provide a 1 / 4 wavelength in-plane delay to the transmitted light in a part of the visible wavelength range. Therefore, when the wavelength dispersion of the small piece layer 220 is different, the polarization state of the polarized light passing through the small piece layer 220 can be different. Therefore, the difference in the polarization state can be used to adjust the color of the small piece layer 220 and the display layer 200 including the small piece layer. If the color is adjusted by using the difference in wavelength dispersion like this, the degree of freedom of the color of the display layer 200 can be increased, so a display medium 10 with high design properties can be realized.

[0110] The wavelength dispersion properties of the small pieces of layers 220 included in one display layer 200 may be different, but are preferably the same.

[0111] In the case where the small layer 220 has an in-plane delay, the small layer 220 may have a direction showing a maximum refractive index. Hereinafter, this direction is sometimes referred to as the "optical axis direction". The optical axis direction may be parallel to the layer plane, or may be perpendicular to the layer plane, or may be located in an inclined direction that is neither parallel nor perpendicular to the layer plane. The small layer 220 and the display layer 200 including the small layer can make various adjustments to the polarization state of the transmitted light according to the optical axis direction and the traveling direction of the transmitted light. Therefore, by appropriately selecting the optical axis direction of the small layer 220, the color of the display layer 200 corresponding to the observation direction can be changed with a wide degree of freedom, thereby realizing a display medium 10 with high design properties.

[0112] In the case where the small sheet layer 220 is formed by a liquid crystal composition or a cured product thereof, the optical axis direction of the small sheet layer 220 can be represented by the substantial maximum tilt angle of the molecules of the liquid crystal compound contained in the small sheet layer 220. The "substantial maximum tilt angle" of the molecules of the liquid crystal compound contained in a certain layer refers to the maximum value of the tilt angle of the molecules of the liquid crystal compound under the assumption that the tilt angle of the molecules on one surface of the layer is 0° and the tilt angle of the molecules changes at a certain ratio in the thickness direction. In addition, the "tilt angle" of the liquid crystal compound molecule represents the angle formed by the liquid crystal compound molecule relative to the layer plane of the layer containing the liquid crystal compound. The tilt angle is equivalent to the largest angle among the angles formed by the direction of the maximum refractive index in the refractive index ellipsoid of the liquid crystal compound molecule and the layer plane. Specifically, it is believed that in the thickness direction of the layer containing the liquid crystal compound, the tilt angle of the liquid crystal compound molecule is smaller the closer to one side of the layer, and the larger the farther away from the above-mentioned side. The actual maximum tilt angle represents the maximum value of the tilt angle, which is calculated under the assumption that the ratio of the change of the tilt angle in such a thickness direction (that is, the ratio of the change that decreases the closer to one side and increases the farther away from one side) is fixed. For example, in a liquid crystal solidified layer obtained by solidifying a layer of a liquid crystal composition formed on a temporary support, the actual maximum tilt angle generally represents the maximum value of the tilt angle of the molecules of the liquid crystal compound under the assumption that the tilt angle of the molecules on the temporary support side of the liquid crystal solidified layer is 0° and the tilt angle of the molecules changes at a certain ratio in the thickness direction. Generally, there is a tendency that the larger the actual maximum tilt angle of the layer, the larger the tilt angle observed as a whole of the liquid crystal compound molecules contained in the layer. Therefore, it is possible to grasp whether the optical axis direction of the small piece layer 220 is parallel or perpendicular to the layer plane, or neither parallel nor perpendicular, based on the actual maximum tilt angle. For example, if the actual maximum tilt angle is 0° to 4°, the optical axis direction can be parallel to the layer plane. In addition, for example, if the actual maximum tilt angle is 86° to 90°, the optical axis direction can be perpendicular to the layer plane. Furthermore, for example, if the substantial maximum tilt angle is greater than 4° and less than 86°, the optical axis direction is in an inclined direction with respect to the layer plane.

[0113] The optical axis directions of the small pieces 220 included in one display layer 200 may be different, but are preferably the same. Therefore, when the small pieces 220 are formed of a liquid crystal composition or a cured product thereof, the substantial maximum tilt angles may be different, but are preferably the same.

[0114] In the case where the small piece layer 220 has an in-plane delay, the type of the small piece layer 220 as a phase difference plate can be divided into several types according to the relationship between the optical axis direction of the small piece layer 220 and the layer plane. There is no particular limitation on the type of the small piece layer 220 as a phase difference plate. When a suitable type is cited, it is preferred that the small piece layer 220 is selected from one or more of a positive A plate, a positive C plate, a tilted O plate, and a tilted hybrid orientation plate. A positive A plate refers to a layer whose optical axis direction is parallel to the layer plane. In addition, a positive C plate refers to a layer whose optical axis direction is perpendicular to the layer plane. Furthermore, a tilted O plate refers to a layer whose optical axis direction is neither parallel nor perpendicular to the layer plane. In addition, a tilted hybrid orientation plate refers to a layer whose angle formed by the optical axis direction relative to the layer plane is different on one side and the other side of the layer. The above-mentioned suitable type of small piece layer 220 and the display layer 200 containing the small piece layer can make various adjustments to the polarization state of the transmitted light according to its type and the direction of travel of the transmitted light. Therefore, by appropriately selecting the type of the small piece layer 220 , the color of the display layer 200 corresponding to the viewing direction can be changed with a wide degree of freedom, so that a display medium 10 with high design properties can be realized.

[0115] The types of the small piece layers 220 included in one display layer 200 may be different, but are preferably the same.

[0116] The small sheet layer 220 may also have a circularly polarized light separation function. The "circularly polarized light separation function" refers to the function of reflecting circularly polarized light in one of the right-handed and left-handed directions and transmitting circularly polarized light in the opposite direction to the right-handed direction. Therefore, the small sheet layer 220 and the display layer 200 including the small sheet layer can reflect a circularly polarized light in one of the right-handed and left-handed directions within the wavelength range that can exert the circularly polarized light separation function. D The circularly polarized light is rotated in the direction D D In the following description, the wavelength range in which the small piece layer 220 can perform the circularly polarized light separation function is sometimes appropriately referred to as the "display wavelength range". The reflectivity of the small piece layer 220 to non-polarized light in the display wavelength range is usually 35% to 50%, preferably 40% to 50%. The small piece layer 220 having the circularly polarized light separation function and the display layer 200 including the small piece layer can selectively reflect the circularly polarized light in the display wavelength range. D Therefore, the function of selectively transmitting and reflecting specific circularly polarized light of a specific wavelength can be effectively utilized to enable the display medium 10 to realize various display modes.

[0117] The rotation direction D of the circularly polarized light that can be reflected by the small sheet layer 220 included in the display layer 200 is D They can be different, but are preferably the same.

[0118] From the viewpoint of realizing a display method that can be viewed by human eyes, the display wavelength range is preferably within the visible wavelength range. The display wavelength ranges of the small pieces 220 included in one display layer 200 may be different, but are preferably the same.

[0119] There is no particular limitation on the material of the small sheet layer 220. Examples of the material of the small sheet layer 220 include inorganic materials and organic materials. Examples of inorganic materials include metals such as aluminum and silver; metal compounds such as titanium oxide, silicon oxide, niobium oxide, tantalum oxide, and magnesium fluoride. In addition, examples of organic materials include acrylic polymers, polystyrene, polyester, polyamide, polyvinyl chloride, polyvinyl acetate, cellulose polymers (such as triacetyl cellulose), polycarbonate, polyurethane, polyolefin, polymers containing alicyclic structures, epoxy resins, melamine resins, phenolic resins, and the like. The material of the small sheet layer 220 may be used alone or in combination of two or more. In addition, when a small sheet layer 220 contains two or more materials, the small sheet layer 220 may have a single-layer structure uniformly containing two or more materials, or may have a multilayer structure containing two or more layers containing one or more materials.

[0120] Among them, it is preferred that the small sheet layer 220 is formed by a solidified material of a liquid crystal composition containing a liquid crystal compound. According to the solidified material of the liquid crystal composition, a small sheet layer 220 having in-plane retardation and a small sheet layer 220 having a circularly polarized light separation function can be efficiently manufactured. Here, for convenience, the material referred to as a "liquid crystal composition" includes not only a mixture of two or more substances, but also a material composed of a single substance. In addition, in the following description, a layer formed by a solidified material of a liquid crystal composition is sometimes referred to as a "liquid crystal solidified layer".

[0121] For example, by curing the liquid crystal compound contained in the liquid crystal composition in a state where the liquid crystal compound is oriented, a small sheet layer 220 with in-plane delay can be formed. To give a specific example, the liquid crystal compound contained in the liquid crystal composition is oriented so that the phase of the liquid crystal composition becomes a liquid crystal phase such as a nematic phase and a smectic phase. When the liquid crystal composition of this liquid crystal phase is cured, the orientation direction of the liquid crystal compound can be fixed. Therefore, the liquid crystal curing layer containing the cured product obtained by the above-mentioned curing can contain the liquid crystal compound oriented as described above, and therefore can have an in-plane delay corresponding to the type of liquid crystal compound, the orientation state of the liquid crystal compound, the thickness and other factors. Therefore, a small sheet layer 220 with in-plane delay can be obtained as the above-mentioned liquid crystal curing layer. The "liquid crystal compound" contained in the cured product of the above-mentioned liquid crystal compound includes not only unreacted liquid crystal compounds, but also liquid crystal compounds that have undergone reactions such as polymerization reactions and cross-linking reactions.

[0122] At this time, by adjusting the orientation direction of the liquid crystal compound in the thickness direction of the liquid crystal solidified layer, the type of the small piece layer 220 as a phase difference plate can be adjusted. For example, in the case where the orientation direction of the liquid crystal compound is parallel to the layer plane, a small piece layer 220 as a positive A plate can be obtained. In addition, for example, in the case where the orientation direction of the liquid crystal compound is perpendicular to the layer plane, a small piece layer 220 as a positive C plate can be obtained. Furthermore, for example, in the case where the orientation direction of the liquid crystal compound is neither parallel to nor perpendicular to the layer plane, a small piece layer 220 as an inclined O plate can be obtained. In addition, for example, in the case where the liquid crystal compound is oriented in such a way that the angle formed by the orientation direction of the liquid crystal compound with respect to the layer plane becomes smaller the closer to one side of the layer and becomes larger the farther away from the above side, a small piece layer 220 as an inclined hybrid orientation plate can be obtained.

[0123] In addition, for example, by curing the liquid crystal composition in a state where the liquid crystal compound contained in the liquid crystal composition is oriented in a manner having cholesteric regularity, a small sheet layer 220 having a circularly polarized light separation function can be formed. Cholesteric regularity refers to the following structure: on a certain plane, the molecular axis is arranged in a certain direction, but the direction of the molecular axis is slightly offset at an angle on the next plane overlapping it, and then further offset at an angle on the next plane, and like this, as the planes arranged in the overlapping arrangement are successively passed through, the angle of the molecular axis in the plane gradually shifts (twists). That is, when the internal molecules of a certain layer have cholesteric regularity, the molecules are arranged in a manner in which the molecular axis is in a certain direction on a first plane inside the layer. On the adjacent second plane inside the layer overlapping the first plane, the direction of the molecular axis is slightly offset at an angle from the direction of the molecular axis in the first plane. On the adjacent third plane further overlapping the second plane, the direction of the molecular axis is further offset at an angle from the direction of the molecular axis in the second plane. Like this, in the planes arranged in the overlapping arrangement, the angle of the molecular axis in the plane is successively offset (twisted). Such a structure in which the direction of the molecular axis is gradually twisted is generally a helical structure, which is an optically chiral structure. Generally, a liquid crystal solidified layer containing a liquid crystal compound having cholesteric regularity reflects circularly polarized light while maintaining its chirality.

[0124] For example, the liquid crystal compound contained in the liquid crystal composition is oriented, and the phase of the liquid crystal composition becomes a cholesteric phase. When the liquid crystal composition of the cholesteric phase is cured, the orientation direction of the liquid crystal compound can be fixed. Therefore, the liquid crystal curing layer containing the cured product obtained by the above-mentioned curing can contain the liquid crystal compound oriented in a manner having cholesteric regularity as described above, and therefore can have a circularly polarized light separation function corresponding to the type of liquid crystal compound, the orientation state of the liquid crystal compound, the thickness and other elements. Therefore, a small sheet layer 220 having a display wavelength range can be obtained as the above-mentioned liquid crystal curing layer.

[0125] The materials of the small piece layers 220 included in one display layer 200 may be different, but are preferably the same.

[0126] [1.3. Arbitrary layer]

[0127] The display medium 10 may further include an arbitrary layer combined with the substrate 100 and the display layer 200. For example, the display medium 10 may include an adhesive layer (not shown) between the substrate 100 and the display layer 200. By using the adhesive layer, the display medium 10 can be efficiently manufactured.

[0128] The adhesive layer is a layer for bonding the substrate 100 and the display layer 200, and can be formed by an adhesive. The adhesive includes not only adhesives in a narrow sense (adhesives having a shear storage elastic modulus of 1 MPa to 500 MPa at 23°C after energy ray irradiation or heat treatment), but also adhesives having a shear storage elastic modulus of less than 1 MPa at 23°C (pressure-sensitive adhesives, etc.). One type of adhesive may be used alone, or two or more types may be used in combination.

[0129] The adhesive layer may be a transparent layer that allows light to pass through, or may be a non-transparent layer that does not allow light to pass through. In addition, when the adhesive layer is transparent, the adhesive layer may have an in-plane retardation, but is preferably an optically isotropic layer with a small in-plane retardation. For example, the in-plane retardation of the adhesive layer when the measurement wavelength is 550nm is preferably 0 to 20nm, more preferably 0 to 10nm, and particularly preferably 0 to 5nm.

[0130] Other examples of the optional layer include a matte layer for improving the smoothness of the display medium 10 ; a hard coat layer such as an impact-resistant polymethacrylate resin layer; an antireflection layer; and an antifouling layer.

[0131] [1.4. Method for manufacturing display medium]

[0132] The manufacturing method of the display medium 10 of the first embodiment of the present invention is not particularly limited, and any manufacturing method that can obtain the above-mentioned display medium 10 can be adopted. From the viewpoint of efficiently manufacturing the display medium 10, it is preferred that the display medium 10 is manufactured by a manufacturing method including the following steps:

[0133] A step (A) of preparing a raw material member having a temporary support and a transfer material layer, wherein the transfer material layer is formed on the temporary support and includes a small piece layer 220;

[0134] A step (B) of forming an adhesive layer on the substrate 100 having the same shape as the display layer 200 when viewed in the thickness direction;

[0135] a step (C) of laminating the transfer material layer and the adhesive layer; and

[0136] A step (D) of peeling off the temporary support.

[0137] Hereinafter, this preferred production method will be described with reference to the drawings. Figure 5 This is a schematic plan view of a raw material member 300 prepared in the method for manufacturing the display medium 10 according to the first embodiment of the present invention, as viewed from the thickness direction. Figure 6 The raw material member 300 prepared in the manufacturing method of the display medium 10 according to the first embodiment of the present invention is schematically shown. Figure 5 The cross-sectional view is a cross-sectional view taken along the VI-VI plane. Figure 7 The figure schematically shows in an enlarged manner the raw material member 300 prepared in the method for manufacturing the display medium 10 according to the first embodiment of the present invention. Figure 5 An enlarged top view of portion VII is shown.

[0138] like Figure 5 and Figure 6 As shown, in step (A), a raw material member 300 including a temporary support 310 and a transfer material layer 320 formed on the temporary support 310 is prepared.

[0139] As the temporary support 310 , for example, a plate, a sheet, a film, or the like formed of an appropriate material can be used. In addition, from the viewpoint of efficiently manufacturing the display medium 10 , it is preferable that the temporary support 310 has an elongated shape.

[0140] For example, resin can be used as the material of the temporary support 310. Examples of the resin include the same resins as those cited as the material of the substrate 100. Among them, a resin containing a polymer having an alicyclic structure is preferred.

[0141] The temporary support 310 may or may not be subjected to a stretching treatment. In addition, the surface of the temporary support 310 may be subjected to a surface treatment such as a rubbing treatment.

[0142] The temporary support 310 may have a single-layer structure having only one layer, or may have a multilayer structure having two or more layers. For example, the temporary support 310 may have a resin film layer formed by the above-mentioned resin and an alignment film formed on the resin film layer. When using such a temporary support 310 having an alignment film, the liquid crystal compound contained in the layer of the liquid crystal composition formed on the alignment film can be well aligned. The alignment film can be formed using a resin containing polymers such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamide-imide, polyetherimide, and polyamide.

[0143] The thickness of the temporary support 310 is preferably 12 μm or more, more preferably 25 μm or more, further preferably 50 μm or more, and is preferably 250 μm or less, more preferably 200 μm or less, further preferably 188 μm or less.

[0144] like Figure 7 As shown, the transfer material layer 320 is a layer including a small piece layer 330 that is the same as the small piece layer 220 included in the display medium 10. In detail, the transfer material layer 320 includes a plurality of small pieces 330 divided by cracks 340, and the small pieces 330 are the same as the small pieces 220 included in the display medium 10. Therefore, each small piece layer 330 is provided at a different position on the surface 310U of the temporary support 310, and the small pieces 330 are divided from each other by the cracks 340 formed in the entire thickness of the transfer material layer 320. Moreover, the transfer material layer 320 is formed by a group of these plurality of small pieces 330.

[0145] Since the small piece layer 330 included in the transfer material layer 320 is the same layer as the small piece layer 220 of the display medium 10, it is usually formed of the same material as the small piece layer 220 of the display medium 10. Furthermore, the small piece layer 330 included in the transfer material layer 320 usually has the same arrangement direction, shape observed in the thickness direction, size and characteristics (in-plane retardation, wavelength dispersion, type as a phase difference plate, circularly polarized light separation function, etc.) as the small piece layer 220 of the display medium 10.

[0146] In addition, since the small piece layer 330 included in the transfer material layer 320 is the same layer as the small piece layer 220 included in the display medium 10, the cracks 340 that divide the small piece layer 330 generally have the same shape, size, and spacing as the cracks 210 that divide the small piece layer 220 when viewed from the thickness direction. Furthermore, the cracks 340 that divide the small piece layer 330 generally include notches 341 and 342 extending in two or more directions, and the directions in which these notches 341 and 342 extend, and the shape, size, and spacing as viewed from the thickness direction are the same as those of the notches 211 and 212 included in the cracks 210 that divide the small piece layer 220.

[0147] However, when viewed from the thickness direction, the transfer material layer 320 may not have the same shape as the display layer 200. The transfer material layer 320 is generally formed larger than the display layer 200. Specifically, the transfer material layer 320 is generally formed large enough to cover the display layer 200. Figure 5 and Figure 6 As shown, an example in which the transfer material layer 320 is formed on most of the surface 310U of the temporary support body 310 which is larger than the display layer 200 is described.

[0148] The transfer material layer 320 is usually arranged at the outermost side of the raw material member 300. Arranged at the outermost side means that the transfer material layer 320 is arranged at the outermost side in the thickness direction of the raw material member 300. Therefore, the surface 320U of the transfer material layer 320 can be exposed on one side of the raw material member 300. The raw material member 300 may have an arbitrary layer between the temporary support 310 and the transfer material layer 320.

[0149] The raw material member 300 can be manufactured by a manufacturing method including, for example, a step of forming a layer on a temporary support body 310 using the material of the small piece layer 330, and a step of forming the crack 340 on the formed layer. In the following description, the layer formed using the material of the small piece layer 330 before the crack 340 is formed is sometimes referred to as a "material layer". The material layer is usually a layer of the same thickness as the small piece layers 220 and 330 formed using the same material as the small piece layers 220 and 330, and can have the same optical properties as the small piece layers 220 and 330 (for example, in-plane retardation, circularly polarized light separation function, etc.).

[0150] The formation method of the material layer is not particularly limited. For example, in the case where a material layer is formed by a solidified material of a liquid crystal composition, a layer of the liquid crystal composition can be formed on a temporary support 310, and the liquid crystal compound contained in the liquid crystal composition is oriented as required, and then the liquid crystal composition is solidified to obtain a material layer as a liquid crystal solidification layer. For example, in the case where it is desired to form a material layer with in-plane retardation, the method described in International Publication No. 2014 / 069515, International Publication No. 2015 / 064581, International Publication No. 2019 / 163611, International Publication No. 2019 / 146468, etc. can be used. In addition, for example, in the case where it is desired to form a material layer with a circularly polarized light separation function, the method described in Japanese Patent Publication No. 2014-174471 can be used. By forming a material layer on a temporary support 310, a multilayer component with a temporary support 310 and a material layer can be obtained.

[0151] Figure 8 The raw material member 300 prepared in the manufacturing method of the display medium 10 according to the first embodiment of the present invention is schematically shown. Figure 7 The cross-sectional view of the cross section cut along the plane VIII-VIII shown in FIG. By forming a crack 340 in a material layer of a multi-layer component (not shown), such as Figure 8 As shown, a raw material member 300 having a transfer material layer 320 including a small piece layer 330 can be obtained. Cracks 340 are generally formed throughout the thickness direction of the material layer, thereby dividing the small piece layer 330 throughout the thickness direction.

[0152] Furthermore, it is preferable that the crack 340 is formed thicker than the thickness T 330 It is particularly preferred that the crack 340 is formed on the entire surface of the raw material member 300 to be deeper than the thickness T of the small piece layer 330. 330 In this case, the top 340C of the crack 340 reaches a position deeper than the surface 310U on the small piece layer 330 side of the temporary support body 310. In addition, the depth T of the crack 340 is 340 Greater than the thickness T of the small platelet layer 330 330 When the crack 340 is deep as described above, the shapes of the small pieces 330 divided by the crack 340 can be made uniform.

[0153] However, it is preferred that the depth T of the crack 340 340 The depth T of the crack 340 is preferably set so as not to completely cut the temporary support body 310. 340 Greater than the thickness T of the small platelet layer 330 330 and is smaller than the thickness T of the raw material component 300 300 .

[0154] The crack 340 can be formed by, for example, pressing a processing tool having a concavoconvex shape against one side of the material layer of the multilayer member. Preferably, the crack 340 is formed by pressing the multilayer member between the support and the processing tool while the multilayer member is supported by the support.

[0155] As a processing tool, a member having a convex portion on the surface corresponding to the shape of the crack 340 observed from the thickness direction of the multilayer member can be used. For example, when the shape of the crack observed from the thickness direction of the multilayer member is a grid, a member having a grid-like convex portion on the surface can be used.

[0156] Only one processing tool may be used, or two or more processing tools may be used in combination. For example, a processing tool having a convex portion on the surface corresponding to a part of the crack 340 and a processing tool having a convex portion on the surface corresponding to another part of the crack 340 may be used in combination. As in the example shown in this embodiment, in the case of forming a crack including notches 341 and 342 extending in different directions, the crack 340 may be formed by pressing a first processing tool having a convex portion on the surface corresponding to the notch 341 extending in one direction and a second processing tool having a convex portion on the surface corresponding to the notch 342 extending in another direction against the multilayer member.

[0157] The cracks 340 may also be formed by pressing the same processing tool multiple times in different configurations on the multi-layered structure.

[0158] Alternatively, a cylindrical processing tool may be used to continuously form cracks in a multi-layer member.

[0159] As the material of the processing tool, a material having strength that does not break even when a multilayer component is pressed and capable of forming a concave-convex structure can be used. Examples of such materials include carbon steel and stainless steel. In addition, from the viewpoint of improving corrosion resistance, strength and thermal conductivity, the processing tool may have one or more multilayer films on the surface. Examples of such films include: nickel, nickel-phosphorus, silicon, copper and the like platings; films formed by ceramic spraying. Furthermore, the processing tool may be provided with: for example, a heating device using a heater, a heat medium, dielectric heating, induction heating, etc.; an anti-static device for anti-static use; a ground wire, etc. Such a processing tool can be manufactured, for example, by forming a concave-convex shape on a cylindrical metal roller by cutting with a cutting tool such as a diamond drill bit or by processing with a laser processing device.

[0160] The pressure when the processing tool is pressed against one side of the material layer of the multilayer component is preferably 0.5MPa or more, more preferably 1MPa or more, further preferably 5MPa or more, preferably 100MPa or less, more preferably 75MPa or less. When the pressure is above the lower limit, a sufficiently deep crack 340 can be formed. When the pressure is below the upper limit, the damage of the raw material component 300 can be suppressed. In order to form the crack 340, the same or different processing tools are pressed against the multilayer component for many times, and the pressing can be performed with the same pressure or with different pressures. It is preferred that the pressing is performed with the same pressure for many times.

[0161] The support member generally has a support surface that can support the surface on the opposite side of the material layer side of the multilayer component. The hardness of the support surface of the support member is preferably D40 or more, more preferably D60 or more, further preferably D70 or more, preferably D99 or less, more preferably D97 or less, and further preferably D95 or less. Here, the hardness represents the value measured by a durometer (type D) according to JIS K-6253. When the hardness of the support surface of the support member is within the above range, cracks of appropriate depth can be easily formed. As the material of the surface of the support member, for example, rubber and resin can be cited.

[0162] Hereinafter, a method of forming the crack 340 using a processing tool will be described with reference to the drawings.

[0163] Fig. 9 This is a perspective view schematically showing an example of a processing tool 400 that can be used in the method for manufacturing the raw material member 300 in the method for manufacturing the display medium 10 according to the first embodiment of the present invention. Fig.10 It is schematically shown Fig. 9 A perspective view of a processing tool 400 is shown. Fig.11 It is a schematic diagram showing Fig.10 A top view of the processing tool 400 in a state where it is cut off and unfolded along the line XI-XI. Fig.12 This is a partial cross-sectional view schematically showing a cross section of a portion near the surface of the processing tool 400 cut along a plane perpendicular to the direction in which the protrusion 410 extends.

[0164] like Fig. 9 As shown, the processing tool 400 is arranged in a manner to contact the surface 360U on the material layer 360 side of the multilayer member 350 so that it can press the multilayer member 350. Fig.10 As shown in FIG. 1 , the processing tool 400 is provided in a cylindrical shape and is rotatable. The outer side surface of the processing tool 400 (the surface in contact with the multilayer member 350) is provided with a concave-convex shape. Fig.11As shown, the concavo-convex shape includes convex portions 410 and concave portions 420 extending in a direction forming an angle θx relative to a certain reference direction L1. As the reference direction L1, an example of using the axial direction of the processing tool 400 perpendicular to the conveying direction of the multilayer component 350 is shown here. The convex portions 410 and concave portions 420 of the processing tool 400 are alternately and repeatedly formed in a direction perpendicular to the direction in which the convex portions 410 extend. The angle θx is not particularly limited, but an example of an angle θx of 45° is shown here. Fig.11 As shown, the concavoconvex shape of the processing tool 400 is a shape arranged in a straight line when viewed from the paper. Fig.12 As shown, it is preferred to appropriately set the distance P between two adjacent protrusions 410. 410 .exist Fig.10 and Fig.11 , reference numerals 430 and 440 denote ends of the processing tool 400 .

[0165] like Fig.12 As shown, the convex portion 410 may have a mountain shape with a cross section having an acute-angled vertex 410T. Preferably, the vertex angle θ of the convex portion 410 is 410 Small. Vertex angle θ 410 For example, it may be greater than 10°, greater than 20°, or greater than 30°, or less than 90°, less than 80°, or less than 60°. As long as the crack 340 can be formed in the material layer 360, the vertex shape of the protrusion 410 may be rounded or chamfered.

[0166] like Fig. 9 As shown, a cylindrical support 450 may be rotatably provided facing the processing tool 400. The support 450 is provided to press the surface of the temporary support body 310 side of the multilayer member 350. Therefore, the multilayer member 350 is pressed between the support 450 and the processing tool 400.

[0167] Fig.13 This is a perspective view schematically showing an example of a processing tool 500 that can be used in the method for manufacturing the raw material member 300 in the method for manufacturing the display medium 10 according to the first embodiment of the present invention. Fig.14 It is schematically shown Fig.13 A perspective view of a processing tool 500 is shown. Fig.15 It is a schematic diagram showing Fig.14 A top view of the processing tool 500 cut along line XV-XV and unfolded.

[0168] like Figure 13 to Figure 15As shown, the processing tool 500 is configured in a manner that contacts the surface 360U on the material layer 360 side of the multilayer component 350 so that it can press the multilayer component 350. The processing tool 500 is set in the same manner as the processing tool 400, except that the directions in which the protrusions 510 and the recesses 520 extend are different. The processing tool 500 includes a protrusion 510 and a recess 520, and the angle θy formed by the protrusion 510 and the recess 520 relative to the reference direction L2 is different from the angle θx of the processing tool 400. As the above-mentioned reference direction L2, an example of using the axial direction of the processing tool 500 perpendicular to the conveying direction of the multilayer component 350 is shown here. The angle θy is not particularly limited, and an example in which the angle θy is 135° is shown here. As shown in FIG. Fig.15 As shown, the concavo-convex shape of the processing tool 500 is a shape in which a straight line is arranged in a direction intersecting the direction in which the convex part 410 and the concave part 420 of the processing tool 400 extend when viewed from the paper. Fig.14 and Fig.15 , reference numerals 530 and 540 denote ends of the processing tool 500 .

[0169] like Fig.13 As shown, a cylindrical support 550 may be rotatably provided facing the processing tool 500. The support 550 is provided to press the surface of the temporary support body 310 side of the multilayer member 350. Therefore, the multilayer member 350 is pressed between the support 550 and the processing tool 500.

[0170] When forming a crack 340 in the material layer 360 of the multilayer component 350 using the above-mentioned processing tools 400, 500 and the supporting members 450, 550, the following processes are performed: a process of forming a notch 341 using a processing tool 400 and a supporting member 450; and a process of forming another notch 342 using another processing tool 500 and a supporting member 550.

[0171] In a process using the processing tool 400 and the support member 450, as Fig. 9 As shown, the multilayer member 350 passes between the processing tool 400 and the support 450, and the protrusion 410 of the processing tool 400 contacts the material layer 360. Then, by pressing the multilayer member 350 between the processing tool 400 and the support 450 in this state, the protrusion 410 of the processing tool 400 enters the inside of the material layer 360, and the score 341 reflecting the shape of the protrusion 410 can be formed. When the degree of pressing is adjusted so that the protrusion 410 of the processing tool 400 enters the inside of the temporary support 310, the score 341 is formed to be larger than the thickness T of the small piece layer 330. 330 deeper, reaching a position deeper than the surface 310U on the small piece layer 330 side of the temporary support body 310 (see Figure 8).

[0172] In addition, in the process using the processing tool 500 and the support member 550, as Fig.13 As shown, the multilayer member 350 passes between the processing tool 500 and the support 550, and the protrusion 510 of the processing tool 500 contacts the material layer 360. Then, by pressing the multilayer member 350 between the processing tool 500 and the support 550 in this state, the protrusion 510 of the processing tool 500 enters the inside of the material layer 360, and the score 342 reflecting the shape of the protrusion 510 can be formed. When the degree of pressing is adjusted so that the protrusion 510 of the processing tool 500 enters the inside of the temporary support 310, the score 342 is formed to be larger than the thickness T of the small piece layer 330. 330 deeper, reaching a position deeper than the surface 310U on the small piece layer 330 side of the temporary support body 310 (see Figure 8 ).

[0173] Therefore, by the method including the steps of forming the score 341 and forming the score 342 as described above, the crack 340 including the score 341 and the score 342 can be formed in the material layer 360, thereby obtaining the raw material member 300. The order of forming the score 341 by the processing tool 400 and forming the score 342 by the processing tool 500 is not particularly limited. For example, the multilayer member 350 may be pressed by the processing tool 400, and then the multilayer member 350 may be pressed by the processing tool 500. In addition, the multilayer member 350 may be pressed by the processing tool 500, and then the multilayer member 350 may be pressed by the processing tool 400.

[0174] In step (B), an adhesive layer having the same shape as the display layer 200 when observed from the thickness direction is formed on the substrate 100. The adhesive layer thus formed can function as a latent image of the display layer 200. There is no limitation on the method for forming the adhesive layer. For example, when a liquid adhesive is used, the adhesive can be applied to the substrate to form the adhesive layer. As the coating method, printing methods such as screen printing and inkjet printing are preferred. In addition, for example, when a film-like or sheet-like adhesive is used, the adhesive can be processed into a suitable shape and the processed adhesive can be bonded to the substrate. As the processing method, for example, cutting, punching, etc. can be cited. Among them, from the viewpoint of suppressing manufacturing costs, printing is preferred.

[0175] After the above steps (A) and (B), a step (C) of laminating the transfer material layer 320 of the raw material member 300 to the adhesive layer formed on the substrate 100 is performed. The laminating is usually performed by pressing the raw material member 300 and the substrate 100 with a pressing tool such as a clamping roller in a state where the surface of the transfer material layer 320 of the raw material member 300 faces the surface of the adhesive layer of the substrate 100. As a result, the substrate 100 and the transfer material layer 320 are bonded to each other through the adhesive layer in the region where the adhesive layer is present.

[0176] After the above-mentioned step (C), a step (D) of peeling off the temporary support 310 is performed. When the temporary support 310 is peeled off, in the area on the substrate 100 where the adhesive layer is formed, the transfer material layer 320 is separated from the temporary support 310 and remains on the substrate 100. Therefore, the display layer 200 is formed by the portion of the transfer material layer 320 remaining on the substrate 100. The display layer 200 includes a group of small pieces 220 as a part of the plurality of small pieces 330 included in the transfer material layer 320. Therefore, the display layer 200 is formed by the group of small pieces 220. On the other hand, in the area on the substrate 100 where there is no adhesive layer, the transfer material layer 320 cannot be separated from the temporary support 310. Therefore, the transfer material layer 320 is peeled off together with the temporary support 310, and therefore no small piece 330 remains in the area on the substrate 100 where there is no adhesive layer. Therefore, the display layer 200 having the shape of an adhesive layer when viewed in the thickness direction can be formed on the substrate 100 , thereby obtaining the display medium 10 .

[0177] In the above-described method for producing the display medium 10 , the order of step (A), step (B), step (C), and step (D) is not limited as long as the display medium 10 can be obtained.

[0178] The above-mentioned method for manufacturing the display medium 10 is preferably performed using the long substrate 100 and the long raw material member 300. In this case, the display medium 10 can be manufactured with high productivity using a roll-to-roll method.

[0179] The above-described method for producing the display medium 10 may further include any step in combination with the step (A), the step (B), the step (C), and the step (D).

[0180] For example, when a curable adhesive is used, the above-mentioned method for producing the display medium 10 may include a step of curing the adhesive. The curing of the adhesive is usually performed after step (C) and before step (D).

[0181] Furthermore, when the long substrate 100 and the long raw material member 300 are used, a long display medium 10 can usually be obtained. Therefore, the above-mentioned method of manufacturing the display medium 10 may include a step of trimming the long display medium 10 into an appropriate shape.

[0182] [1.5. Main effects of display media]

[0183] The display medium 10 described above can realize various display modes using the display layer 200 .

[0184] For example, since the display layer 200 can be formed in various colors and shapes, it is possible for an observer who observes the display layer 200 to view various images. Therefore, the display medium 10 can contribute to improving the degree of freedom of display methods.

[0185] In particular, the display layer 200 including the small sheet layer 220 having in-plane retardation is usually transparent and therefore difficult to be observed by naked eyes. However, when the display medium 10 is set between two linear polarizers set to orthogonal Nicols or parallel Nicols and transmission observation is performed, the display layer 200 can be observed according to the setting angle of the display medium 10. Therefore, the above-mentioned display layer 200 can help to realize a variety of display modes corresponding to the observation method. "Orthogonal Nicols" means a configuration in which the absorption axes of the two linear polarizers are orthogonal when observed from the thickness direction. In addition, "parallel Nicols" means a configuration in which the absorption axes of the two linear polarizers are parallel when observed from the thickness direction.

[0186] In addition, the display layer 200 including the small sheet layer 220 having the circularly polarized light separation function can be viewed by the naked eye under non-polarized conditions. In addition, the display layer 200 can be viewed when observed through a circular polarizing plate that can transmit the circularly polarized light that the small sheet layer 220 can reflect. However, it is difficult to view the display layer 200 when observed through a circular polarizing plate that does not transmit the circularly polarized light that the small sheet layer 220 can reflect. In addition, it is difficult to view the display layer 200 when observed by irradiating only the circularly polarized light that the small sheet layer 220 cannot reflect. Therefore, the above-mentioned display layer 200 can contribute to the realization of a variety of display modes corresponding to the observation method. In particular, since the display layer 200 including the small sheet layer 220 having the circularly polarized light separation function can reflect the circularly polarized light of the color corresponding to the display wavelength range of the small sheet layer 220, the display layer 200 can be displayed using the color corresponding to the display wavelength range. Therefore, it can effectively contribute to improving the degree of freedom of the display mode.

[0187] Furthermore, the display layer 200 can be observed even without magnifying the display medium 10 through a magnifying glass or a microscope. However, since the small piece layer 220 included in the display layer 200 is small, it is difficult to observe without magnifying, and it is difficult to identify the shape, size and configuration. In particular, the small piece layer 220 with a width within the above-mentioned specific range is difficult to observe unless a high-magnification microscope is used, and it is difficult for the observer to know that the small piece layer 220 is included in the display layer 200. Therefore, according to the above-mentioned display medium 10, it can help to realize various display methods based on the display layer 200, and it can increase the difficulty of counterfeiting.

[0188] In addition, the small piece layer 220 of the display medium 10 is arranged in two or more directions in one display layer 200. The small piece layer 220 arranged in two or more directions has a high regularity of arrangement. By arranging the small piece layer 220 with high regularity, the manufacturing difficulty of the display medium 10 is increased. Therefore, according to the above-mentioned display medium 10, the difficulty of counterfeiting can be increased.

[0189] The display medium 10 described above can be efficiently manufactured using a roll-to-roll method, and thus can be manufactured at a low cost, thereby having commercial value.

[0190] [2. Second Embodiment]

[0191] In the first embodiment, an example of a display medium 10 having a transparent substrate 100 is described, but the display medium may also have a non-transparent substrate. For example, the display medium may include a substrate having a colored layer. Hereinafter, an embodiment of a display medium having a colored layer will be described.

[0192] Fig.16 2 is a schematic top view of the display medium 20 according to the second embodiment of the present invention as viewed from the thickness direction. Fig.17 The display medium 20 of the second embodiment of the present invention is schematically shown. Fig.16 The cross-sectional view of the cross section cut along the XVII-XVII plane shown. Fig.18 The display medium 20 according to the second embodiment of the present invention is schematically and enlarged. Fig.16 An enlarged plan view of the XVIII portion is shown. In the second embodiment, the same elements as those described in the first embodiment are denoted by the same reference numerals as those used in the first embodiment.

[0193] like Figure 16 to Figure 18As shown, the display medium 20 of the second embodiment of the present invention is configured in the same manner as the display medium 10 of the first embodiment except that it has a non-transparent substrate 600 instead of the transparent substrate 100. Therefore, the display medium 20 has a substrate 600 and a display layer 200 formed on the substrate 600, and the display layer 200 includes a plurality of small pieces 220 formed with high regularity.

[0194] In the substrate 600, a colored layer 610 is provided in combination with a supporting layer 110. Since the colored layer 610 does not transmit light in a part or all of the visible wavelength range, the substrate 600 is non-transparent. In this embodiment, an example is shown in which the substrate 600 has a supporting layer 110 and a colored layer 610 in order from the display layer 200 side for explanation. However, the substrate 600 may also have a colored layer 610 and a supporting layer 110 in order from the display layer 200 side. In addition, the substrate 600 may omit the supporting layer 110 and be provided in a manner that the colored layer 610 itself can support the display layer 200.

[0195] The colored layer 610 can be formed using a material that can block part or all of the light in the visible wavelength range. Examples of the material of the colored layer 610 include: resin containing a colorant such as a pigment or dye; paper; leather; cloth; wood; metal; and a metal compound. These materials can be used alone or in combination of two or more.

[0196] According to the display medium 20 of the second embodiment of the present invention, the same advantages as the display medium 10 described in the first embodiment can be obtained. Furthermore, according to the colored layer 610, various designs can be expressed by the substrate 600 itself having the colored layer 610. Therefore, it can effectively contribute to improving the degree of freedom of the display method. In addition, according to the colored layer 610, part or all of the light passing through the substrate 600 can be blocked, so the visibility of the display layer 200 can be improved. Moreover, even if the visibility of the display layer 200 is improved in this way, it is difficult to see the small piece layer 220 without magnified observation, so according to the display medium 20, the difficulty of counterfeiting can be increased.

[0197] [3. Third embodiment]

[0198] The substrate of the display medium may have a circularly polarized light separation function. Such a substrate having a circularly polarized light separation function generally includes a selective reflection layer having a circularly polarized light separation function. The following describes an embodiment of a display medium including a selective reflection layer.

[0199] Fig.19 : is a schematic top view of the display medium 30 according to the third embodiment of the present invention as viewed from the thickness direction. Fig. 20The display medium 30 of the third embodiment of the present invention is schematically shown. Fig.19 The cross-sectional view of the cross section cut along the XX-XX plane shown. Fig.21 The display medium 30 according to the third embodiment of the present invention is schematically and enlarged. Fig.19 An enlarged plan view of the XXI portion shown in FIG. In the third embodiment, the same elements as those described in the first embodiment are denoted by the same reference numerals as those used in the first embodiment.

[0200] like Figure 19 to Figure 21 As shown, the display medium 30 of the third embodiment of the present invention includes a substrate 700 having a circularly polarized light separation function instead of the substrate 100, and is configured in the same manner as the display medium 10 of the first embodiment. Therefore, the display medium 30 includes a substrate 700 and a display layer 200 formed on the substrate 700, and the display layer 200 includes a plurality of small pieces 220 formed with high regularity.

[0201] The substrate 700 includes a selective reflection layer 710 in combination with the support layer 110. Since the selective reflection layer 710 has a circularly polarized light separation function, the substrate 700 can obtain the circularly polarized light separation function. In this embodiment, an example in which the substrate 700 includes the selective reflection layer 710 and the support layer 110 in order from the display layer 200 side is shown for explanation. However, the substrate 700 may also include the support layer 110 and the selective reflection layer 710 in order from the display layer 200 side. In addition, the substrate 700 may omit the support layer 110 and be provided in a manner that the selective reflection layer 710 itself can support the display layer 200.

[0202] Since the selective reflection layer 710 has a circularly polarized light separation function, it can reflect a light in a rotation direction D within a wavelength range in which the circularly polarized light separation function can be exerted. S The circularly polarized light is rotated in the direction D S In the following description, the wavelength range in which the selective reflection layer 710 can perform the circularly polarized light separation function is sometimes appropriately referred to as the "substrate reflection range". The reflectivity of the selective reflection layer 710 to non-polarized light in the substrate reflection range is usually 35% to 50%, preferably 40% to 50%.

[0203] When the small piece layer 220 included in the display layer 200 has a circularly polarized light separation function, the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710 is S The rotation direction D of the circularly polarized light that can be reflected by the small platelet layer 220 D The same, or the opposite.

[0204] The wavelength width of the substrate reflection range of the selective reflection layer 710 is preferably wide. The specific wavelength width of the substrate reflection range is preferably 70 nm or more, more preferably 100 nm or more, further preferably 200 nm or more, and particularly preferably 400 nm or more. Since the wavelength width of the substrate reflection range is wide, the range of colors of circularly polarized light that can be reflected by the selective reflection layer 710 can be increased. Since such a selective reflection layer 710 can be viewed in low-saturation colors, when a display layer 200 with a high-saturation color is formed, the visibility of the display layer 200 can be improved. There is no particular upper limit to the wavelength width of the substrate reflection range, and for example, it can be 600 nm or less.

[0205] In the case where the small piece layer 220 included in the display layer 200 has a circularly polarized light separation function, the substrate reflection range of the selective reflection layer 710 may overlap with the display wavelength range of the small piece layer 220 included in the display layer 200, or may not overlap. In the case of overlap, a part of the substrate reflection range and a part of the display wavelength range may overlap, or a part of the substrate reflection range and the entire display wavelength range may overlap, or the entire substrate reflection range and a part of the display wavelength range may overlap, or the entire substrate reflection range and the entire display wavelength range may overlap. Among them, it is preferred that the display wavelength range is included in the substrate reflection range by overlapping a part of the substrate reflection range and the entire display wavelength range. In this case, the visibility of the display layer 200 under non-polarized light can be reduced, and the visibility of the display layer 200 under circularly polarized light can be improved. For example, assuming that the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710 is S and the rotation direction D of the circularly polarized light that can be reflected by the small piece layer 220 included in the display layer 200 D The opposite is true. In this case, when non-polarized light is irradiated to the display layer 200 side of the display medium 30, both the selective reflection layer 710 and the display layer 200 reflect circularly polarized light. At this time, if the display wavelength range is included in the substrate reflection range, both the area with the display layer 200 and the area without the display layer 200 can be viewed in the color of the selective reflection layer 710. Therefore, for an observer observing the display layer 200 side of the display medium 30, the visibility of the display layer 200 is low. However, when the display medium 30 is irradiated with a rotation direction D D When circularly polarized light is reflected by the display layer 200, the selective reflective layer 710 does not reflect the circularly polarized light, while the display layer 200 reflects the circularly polarized light. Therefore, an observer observing the display layer 200 side of the display medium 30 can clearly observe the circularly polarized light reflected by the display layer 200, so the visibility of the display layer 200 can be improved.

[0206] In the case where the small piece layer 220 included in the display layer 200 has a circularly polarized light separation function, it is preferred that the wavelength width of the substrate reflection range of the selective reflection layer 710 is wider than the wavelength width of the display wavelength range of the small piece layer 220. In this case, since the display wavelength range is included in the substrate reflection range, the visibility of the display layer 200 under non-polarized light can be reduced, and the visibility of the display layer 200 under circularly polarized light can be improved.

[0207] It is preferred that the substrate reflection range of the selective reflection layer 710 includes the entire visible wavelength range. Therefore, the lower limit of the substrate reflection range is preferably 400 nm or less, and the upper limit of the substrate reflection range is preferably 780 nm or more.

[0208] The display medium 30 according to the third embodiment of the present invention can obtain the same advantages as the display medium 10 described in the first embodiment. Furthermore, according to the selective reflection layer 710, various designs can be expressed by the substrate 700 itself having the selective reflection layer 710. Therefore, it can effectively contribute to improving the degree of freedom of the display method. In addition, according to the selective reflection layer 710, when light is irradiated to the substrate 700, light having a specific rotation direction D can be selectively reflected. S Therefore, when the display layer 200 includes the small sheet layer 220 having in-plane retardation, the polarization state of the circularly polarized light can be adjusted by the display layer 200 to realize various display modes.

[0209] For example, suppose that the display medium 30 is irradiated with unpolarized light when the small piece layer 220 included in the display layer 200 has an in-plane retardation capable of functioning as a quarter-wave plate. In this case, it is difficult for an observer who observes the display medium 30 with the naked eye to see the display layer 200. However, an observer who observes the display layer 200 side of the display medium 30 through a linear polarizing plate can see the display layer 200 when the angle formed by the absorption axis of the linear polarizing plate and the slow axis of the small piece layer 220 included in the display layer 200 is appropriate.

[0210] Furthermore, for example, it is assumed that the display layer 200 side of the display medium 30 is irradiated with circularly polarized light when the small piece layer 220 included in the display layer 200 has an in-plane retardation capable of functioning as a quarter-wave plate.

[0211] The rotation direction of the circularly polarized light irradiating the display medium 30 and the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710 are different. SUnder the same circumstances, the selective reflection layer 710 can reflect the circularly polarized light with high intensity in the area where the display layer 200 is not provided. However, in the area where the display layer 200 is provided, the circularly polarized light is converted into linearly polarized light by the display layer 200, and the selective reflection layer 710 can only reflect the linearly polarized light with low intensity. Therefore, the display layer 200 can be viewed as a portion with weaker reflection than the surrounding.

[0212] On the other hand, when the rotation direction of the circularly polarized light irradiating the display medium 30 is different from the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710, S In the opposite case, the selective reflection layer 710 cannot reflect the circularly polarized light in the region where the display layer 200 is not provided. However, in the region where the display layer 200 is provided, the circularly polarized light is converted into linearly polarized light by the display layer 200, and the selective reflection layer 710 can reflect the linearly polarized light. Therefore, the display layer 200 can be viewed as a portion with stronger reflection than the surrounding.

[0213] Furthermore, for example, assume that the display medium 30 is irradiated with unpolarized light when the small sheet layer 220 included in the display layer 200 has an in-plane retardation capable of functioning as a half-wave plate. In this case, it is difficult for an observer who observes the display medium 30 with the naked eye to see the display layer 200. However, an observer who observes the display layer 200 side of the display medium 30 through an appropriate circular polarizing plate can see the display layer 200.

[0214] Furthermore, for example, it is assumed that the display layer 200 side of the display medium 30 is irradiated with circularly polarized light when the small piece layer 220 included in the display layer 200 has an in-plane retardation capable of functioning as a half-wave plate.

[0215] The rotation direction of the circularly polarized light irradiating the display medium 30 and the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710 are different. S Under the same circumstances, the selective reflection layer 710 can reflect the circularly polarized light in the region where the display layer 200 is not provided. However, in the region where the display layer 200 is provided, since the rotation direction of the circularly polarized light changes to the opposite direction after passing through the display layer 200, the selective reflection layer 710 cannot reflect the circularly polarized light. Therefore, the display layer 200 can be viewed as a portion where the reflection is weaker than the surrounding or no reflection is provided.

[0216] On the other hand, when the rotation direction of the circularly polarized light irradiating the display medium 30 is different from the rotation direction D of the circularly polarized light that can be reflected by the selective reflection layer 710, SIn the opposite case, the selective reflection layer 710 cannot reflect the circularly polarized light in the region where the display layer 200 is not provided. However, in the region where the display layer 200 is provided, the rotation direction of the circularly polarized light changes to the opposite direction after passing through the display layer 200, and the selective reflection layer 710 can reflect the circularly polarized light. Therefore, the display layer 200 can be viewed as a portion with stronger reflection than the surrounding.

[0217] As described above, the display medium 30 of this embodiment can contribute to the realization of various display modes. Moreover, even when the display modes are diversified as described above, the small piece layer 220 is difficult to see without magnification, so the display medium 30 can increase the difficulty of counterfeiting.

[0218] In the third embodiment described above, the substrate 700 does not include a colored layer (see the second embodiment), but the substrate 700 may include a colored layer in combination with the selective reflection layer 710 .

[0219] [4. Other embodiments]

[0220] In the above-mentioned embodiment, an example in which only one display layer is provided on a substrate is shown for illustration, but a plurality of display layers may be provided on a substrate. In addition, the plurality of display layers may be the same or different. Therefore, for example, among the plurality of display layers, (i) the shape of the display layer observed from the thickness direction, (ii) the size of the display layer observed from the thickness direction, (iii) the arrangement direction of the small layer observed from the thickness direction, (iv) the shape of the small layer observed from the thickness direction, (v) the size of the small layer observed from the thickness direction, (vi) the thickness of the small layer, (vii) the in-plane delay of the small layer, (viii) the wavelength dispersion of the small layer, (ix) the type of the small layer as a phase difference plate, (x) the slow axis direction of the small layer, (xi) the display wavelength range of the small layer, (xii) the rotation direction D of the circularly polarized light that the small layer can reflect D (xiii) The elements such as the material of the small sheet layer may be the same or different.

[0221] Thus, for example, the display medium may have a first display layer comprising a first set of small layers having a slow axis in a certain direction and a second display layer comprising a second set of small layers having a slow axis in a direction not parallel to the slow axis.

[0222] In addition, for example, the display medium may have: a first display layer, which includes a first group of small layers having a first display wavelength range capable of reflecting circularly polarized light with a certain rotation direction; and a second display layer, which includes a second group of small layers having a second display wavelength range capable of reflecting circularly polarized light with a rotation direction opposite to the above-mentioned rotation direction.

[0223] Furthermore, the display medium may also include elements other than the above as long as the effect of the present invention is not significantly impaired. For example, the display medium may have a metal reflective layer. Such a metal reflective layer may be provided, for example, between the substrate and the display layer. In addition, the metal reflective layer may be provided not only in the area where the display layer is provided, but also in the area where the display layer is not provided.

[0224] In addition, for example, the display medium may have a covering layer for protecting the above-mentioned layers. Preferably, these covering layers are arranged on the outside of the above-mentioned layers. For example, the display medium may have a covering layer, a substrate, a display layer and a covering layer in the thickness direction. Such a covering layer can be formed of a transparent material, for example, can be formed of a resin.

[0225] Furthermore, for example, as long as the effect of the present invention is not significantly impaired, the display medium may also have an arbitrary layer with a small in-plane retardation between the above-mentioned layers and as the outermost layer of the display medium. Hereinafter, an arbitrary layer with a small in-plane retardation like this is sometimes referred to as a "low Re layer". The specific in-plane retardation of the low Re layer is usually greater than 0 nm and less than 5 nm. The low Re layer preferably has high light transmittance, and the total light transmittance of the low Re layer is preferably greater than 80%, and more preferably greater than 85%. As materials for such a low Re layer, for example: hard polyvinyl chloride, soft polyvinyl chloride, acrylic resin, glass, polycarbonate (PC), and polyethylene terephthalate (PET) can be cited. The specific material can be appropriately selected according to the purpose of the display medium, the required texture, durability and mechanical strength.

[0226] [5. Display items]

[0227] A display article according to one embodiment of the present invention comprises a base article and the display medium disposed on the base article. By disposing the display medium on the base article, a display method based on the display medium can be given to the base article, thereby obtaining a display article with excellent design.

[0228] The base object is an object on which the display medium is set, and its scope is not limited. Examples of base objects include: cloth products such as clothes; leather products such as bags and shoes; metal products such as screws; paper products such as price tags; plastic products such as cards and plastic banknotes; and rubber products such as tires, but are not limited to these examples.

[0229] Example

[0230] The present invention will be described in detail below with reference to the following examples, but the present invention is not limited to the following examples and can be implemented with any modifications without departing from the scope of the claims and their equivalents.

[0231] In the following description, "%" and "parts" indicating amounts are based on weight unless otherwise specified. In addition, the following operations are performed in the atmosphere at normal temperature and pressure unless otherwise specified.

[0232] In the following description, unless otherwise specified, a commercially available adhesive was used: "LUCIACS CS9621T" (thickness 25 μm, visible light transmittance 90% or more, in-plane retardation 3 nm or less) manufactured by Nitto Denko Corporation.

[0233] [Measurement method of in-plane retardation and slow axis direction]

[0234] When the measurement wavelength was 550 nm, the in-plane retardation and the slow axis direction were measured using a phase difference meter ("Axoscan" manufactured by Axometrics).

[0235] [Method for measuring the substantial maximum tilt angle]

[0236] When the measurement wavelength is 590nm, a phase difference meter ("Axoscan" manufactured by Axometrics) is used to measure the delay of the liquid crystal curing layer. The incident angle relative to the liquid crystal curing layer is changed in the range of -50° to 50°, and the measurement is performed multiple times. At this time, the measurement direction is set to be perpendicular to the fast axis of the liquid crystal curing layer in each measurement.

[0237] Based on the measured retardation, the substantial maximum tilt angle of the molecules of the liquid crystal compound contained in the liquid crystal cured layer is analyzed using the analysis software attached to the above-mentioned phase difference meter (analysis software "Multi-Layer Analysis" manufactured by AxoMetrics; analysis conditions: analysis wavelength 590nm, number of layer divisions 20 layers).

[0238] [Method for measuring reflectivity of cholesteric liquid crystal layer]

[0239] The temporary support was peeled off from the multilayer member to obtain a liquid crystal cured layer. The reflectivity of the liquid crystal cured layer when non-polarized light (wavelength 400 nm to 800 nm) was measured using an ultraviolet visible spectrophotometer ("UV-Vis 550" manufactured by JASCO Corporation).

[0240] [Manufacturing Example 1: Manufacture of Multilayer Structure (Q1)]

[0241] According to Example 1 of International Publication No. 2017 / 057005, a multilayer structure (Q1) having a temporary support body as a long film formed of a thermoplastic norbornene resin and a liquid crystal curing layer as a positive A plate formed on the temporary support body was manufactured. The in-plane retardation Re of the liquid crystal curing layer is 138nm, the thickness of the liquid crystal curing layer is 2.3μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support body is 45°. The liquid crystal curing layer has an inverse wavelength dispersion property in which the in-plane retardation gradually increases with the increase of the measured wavelength.

[0242] [Manufacturing Example 2: Manufacture of Multilayer Structure (Q2)]

[0243] According to Example 1 of International Publication No. 2019 / 188519, a multilayer structure (Q2) having a temporary support body as a long film formed of a thermoplastic norbornene resin and a liquid crystal curing layer as a tilted hybrid orientation plate formed on the temporary support body was manufactured. The in-plane retardation Re of the liquid crystal curing layer is 138nm, the thickness of the liquid crystal curing layer is 4.0μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support body is 45°. In addition, since the actual maximum tilt angle of the liquid crystal curing layer is 63°, it is confirmed that the optical axis direction of the liquid crystal curing layer is neither parallel nor perpendicular to the layer plane. Furthermore, the liquid crystal curing layer has an anti-wavelength dispersion property in which the in-plane retardation gradually increases with the increase of the measured wavelength.

[0244] [Manufacturing Example 3: Manufacture of Multilayer Structure (Q3)]

[0245] The type of liquid crystal compound was changed to "LC242" manufactured by BASF AG, and the thickness was changed in a manner to obtain an in-plane delay that can function as a 1 / 4 wave plate. In addition, a temporary support body having a long film formed of a thermoplastic norbornene resin and a multilayer component (Q3) formed on the temporary support body was manufactured using the same method as in Example 1. The in-plane delay Re of the liquid crystal solidification layer is 143nm, the thickness of the liquid crystal solidification layer is 1.2μm, and the angle formed by the slow axis of the liquid crystal solidification layer relative to the long side direction of the temporary support body is 45°. The liquid crystal solidification layer has a positive wavelength dispersion in which the in-plane delay gradually decreases as the measured wavelength increases.

[0246] [Manufacturing Example 4: Manufacture of Multilayer Structure (H1)]

[0247] The thickness was changed in such a way that an in-plane delay capable of functioning as a 1 / 2 wave plate could be obtained. In addition, a temporary support body having a long film formed of a thermoplastic norbornene resin and a multilayer structure (H1) having a liquid crystal curing layer formed on the temporary support body was manufactured by the same method as in Manufacturing Example 3. The in-plane delay Re of the liquid crystal curing layer was 280 nm, the thickness of the liquid crystal curing layer was 2.4 μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support body was 45°. The liquid crystal curing layer has a positive wavelength dispersion property in which the in-plane delay gradually decreases as the measured wavelength increases.

[0248] [Manufacturing Example 5: Manufacture of Multilayer Structure (H2)]

[0249] The type of liquid crystal compound is changed to a compound represented by the following formula (X1), and the thickness is changed in a manner that an in-plane delay capable of functioning as a 1 / 2 wave plate can be obtained. In addition, a temporary support body having a long film formed of a thermoplastic norbornene resin and a multilayer component (H2) formed on the temporary support body is manufactured by the same method as in Example 4. The in-plane delay Re of the liquid crystal solidification layer is 275nm, the thickness of the liquid crystal solidification layer is 1.2μm, and the angle formed by the slow axis of the liquid crystal solidification layer relative to the long side direction of the temporary support body is 45°. The liquid crystal solidification layer has a positive wavelength dispersion in which the in-plane delay gradually decreases as the measured wavelength increases.

[0250] [Chemical formula 1]

[0251]

[0252] [Manufacturing Example 6: Manufacture of a multilayer member (CLC_W)]

[0253] A liquid crystal composition was prepared by mixing 100 parts of a photopolymerizable liquid crystal compound represented by the above chemical formula (X1), 25 parts of a photopolymerizable non-liquid crystal compound represented by the following chemical formula (X2), 8 parts of a chiral agent ("LC756" manufactured by BASF AG), 5 parts of a photopolymerization initiator ("Irgacure 907" manufactured by Ciba Japan KK), 0.15 parts of a surfactant ("S-420" manufactured by AGC Seimi Chemical Co., Ltd.), and 320 parts of cyclopentanone as a solvent.

[0254] [Chemical formula 2]

[0255]

[0256] A long polyethylene terephthalate film ("A4100" manufactured by Toyobo Co., Ltd.; thickness 100 μm) was prepared as a temporary support. The temporary support was attached to the outlet of the film conveying device, and the following operation was performed while conveying the temporary support in the longitudinal direction.

[0257] The surface of the temporary support was subjected to a friction treatment in the longitudinal direction parallel to the conveying direction. Next, a liquid crystal composition was applied to the surface of the temporary support subjected to the friction treatment using a die coater to form a layer of the liquid crystal composition. The layer of the liquid crystal composition was subjected to an orientation treatment by heating at 120°C for 4 minutes, and the liquid crystal composition was oriented in a manner showing a cholesteric liquid crystal phase. Thereafter, a broadband treatment was applied to the layer of the liquid crystal composition. In the broadband treatment, multiple 5 mJ / cm 2 ~30mJ / cm 2 The liquid crystal composition layer was irradiated with weak ultraviolet light and heated at 100°C to 120°C to control the wavelength range capable of performing the circularly polarized light separation function to have the desired wavelength width. Then, the layer of the liquid crystal composition was irradiated with 800 mJ / cm 2 The layer of the liquid crystal composition was cured by ultraviolet rays. Thus, a multilayer component (CLC_W) having a temporary support and a liquid crystal curing layer having a circularly polarized light separation function was obtained. The reflectivity of the liquid crystal curing layer of the multilayer component (CLC_W) was measured using the above-mentioned measurement method. The measurement result showed that the liquid crystal curing layer had a wavelength range in which the reflectivity of non-polarized light was 40% or more in the wavelength range of 450nm to 700nm. The thickness of the liquid crystal curing layer was 5.2μm.

[0258] [Manufacturing Example 7: Manufacture of Multilayer Structure (CLC_R)]

[0259] The amount of chiral agent ("LC756" manufactured by BASF AG) was changed to 7 parts, and broadband treatment was not implemented. In addition, a multilayer component (CLC_R) having a temporary support and a liquid crystal curing layer having a circularly polarized light separation function was manufactured using the same method as in Manufacturing Example 6. The reflectivity of the liquid crystal curing layer of the multilayer component (CLC_R) was measured using the above-mentioned measurement method. The results of the measurement are: the liquid crystal curing layer has a central wavelength near 650nm, and has a wavelength range in which the reflectivity of non-polarized light is more than 40% within a wavelength range with a half-peak width of about 20nm. When the liquid crystal curing layer is visually observed under natural light, the liquid crystal curing layer is viewed in red. The thickness of the liquid crystal curing layer is 3.5μm.

[0260] [Manufacturing Example 8: Manufacture of a multilayer member (CLC_G)]

[0261] No broadband processing was implemented. In addition, a multilayer component (CLC_G) having a temporary support and a liquid crystal curing layer having a circularly polarized light separation function was manufactured using the same method as in Manufacturing Example 6. The reflectivity of the liquid crystal curing layer of the multilayer component (CLC_G) was measured using the above-mentioned measurement method. The result of the measurement was that the liquid crystal curing layer had a central wavelength near 550nm and had a wavelength range in which the reflectivity of non-polarized light was more than 40% within a wavelength range of about 20nm at half-peak width. When the liquid crystal curing layer was visually observed under natural light, the liquid crystal curing layer was viewed in green. The thickness of the liquid crystal curing layer was 3.5μm.

[0262] [Manufacturing Example 9: Manufacture of Multilayer Structure (CLC_rG)]

[0263] 16 parts of the compound (X3) represented by the following chemical formula (X3) were used instead of 8 parts of a chiral agent ("LC756" manufactured by BASF AG). No broadband treatment was performed. In addition, a multilayer component (CLC_rG) having a temporary support and a liquid crystal curing layer having a circularly polarized light separation function was manufactured using the same method as in Manufacturing Example 6. The reflectivity of the liquid crystal curing layer of the multilayer component (CLC_rG) was determined using the above-mentioned measurement method. The results of the measurement are as follows: the liquid crystal curing layer has a central wavelength near 550nm, and has a wavelength range in which the reflectivity of non-polarized light is 40% or more within a wavelength range in which the half-peak width is about 20nm. When the liquid crystal curing layer is visually observed under natural light, the liquid crystal curing layer is viewed in green. The thickness of the liquid crystal curing layer is 3.5μm.

[0264] [Chemical formula 3]

[0265]

[0266] (Compound name)

[0267] D-Mannitol, 1,4:3,6-dihydro-, 2,5-bis[4-[[[6-[[[4-[(1-oxo-2-propen-1-yl)oxy]butoxy]carbonyl]oxy]-2-naphthyl]carbonyl]oxy]benzoate]

[0268] [Manufacturing Example 10: Manufacture of Multilayer Structure (CLC_B)]

[0269] The amount of chiral agent ("LC756" manufactured by BASF AG) was changed to 10 parts, and broadband treatment was not implemented. In addition, a multilayer component (CLC_B) having a temporary support and a liquid crystal curing layer having a circularly polarized light separation function was manufactured using the same method as in Manufacturing Example 6. The reflectivity of the liquid crystal curing layer of the multilayer component (CLC_B) was determined using the above-mentioned measurement method. The results of the measurement are: the liquid crystal curing layer has a central wavelength near 450nm, and has a wavelength range in which the reflectivity of non-polarized light is more than 40% within a wavelength range with a half-peak width of about 20nm. When the liquid crystal curing layer is visually observed under natural light, the liquid crystal curing layer is viewed in blue. The thickness of the liquid crystal curing layer is 3.5μm.

[0270] [Manufacturing Example 11: Manufacture of Phase Difference Film (R1)]

[0271] A resin film formed of a thermoplastic norbornene resin ("Zeonor Film" manufactured by Zeon Co., Ltd. of Japan; a film manufactured by extrusion molding, unstretched product) was prepared. The resin film was stretched in one direction at a stretching temperature of 130° C. to obtain a phase difference film (R1) having an in-plane retardation capable of functioning as a 1 / 2 wave plate. The phase difference film (R1) had a thickness of 38 μm and an in-plane retardation of 280 nm.

[0272] [Manufacturing Example 12: Manufacture of Phase Difference Film (R2)]

[0273] A retardation film (R2) was produced in the same manner as in Production Example 11 except that the stretching ratio was changed so as to obtain an in-plane retardation capable of functioning as a quarter-wave plate. The retardation film (R2) had a thickness of 47 μm and an in-plane retardation of 143 nm.

[0274] [Manufacturing Example 13: Manufacture of Circularly Polarized Light Selective Reflection Film (D)]

[0275] The retardation film (R2) produced in Production Example 12 was bonded to the linearly polarized light selective reflection film "DBEF" produced by 3M Company via a commercially available adhesive to produce a circularly polarized light selective reflection film (D). The bonding was performed by adjusting the slow axis direction of the retardation film (R2) so that the circularly polarized light selective reflection film (D) could selectively reflect right-handed circularly polarized light.

[0276] [Example 101]

[0277] (Shows a brief description of the media)

[0278] Fig. 22 is a top view schematically showing the display medium 800 manufactured in Example 101. In addition, Fig.23is a cross-sectional view schematically showing a display medium 800 manufactured in Example 101.

[0279] like Fig. 22 and Fig.23 As shown, the display medium 800 manufactured in Example 101 has a display layer 830 on a substrate 810 via an adhesive layer 820. When viewed from the thickness direction, the display layer 830 has a block-shaped letter "T" shape with a thickness of approximately 7 mm. The manufacturing method of the display medium 800 is described below.

[0280] (Manufacturing of raw material components)

[0281] The liquid crystal cured layer of the multilayer member (Q1) produced in Production Example 1 was scored by the 3 mm square cross cut method described below.

[0282] <3mm square cross-section method>

[0283] In the 3 mm square cross-cut method, a processing device ("Cross Cut Adhesion Test Kit CC3000" manufactured by TQC) was used to form a plurality of straight lines on the liquid crystal solidification layer according to the method of JIS-K5600-5-6. The lines are formed at intervals of 3 mm in two directions perpendicular to each other. In addition, the depth of the lines is adjusted in a manner that is deeper than the thickness of the liquid crystal solidification layer and does not completely cut off the temporary support. The depth of the lines is adjusted by adjusting the cutting depth of the blade of the above-mentioned processing device.

[0284] By forming the scoring based on the above-mentioned 3 mm square cross-cutting method, cracks are formed in the liquid crystal solidified layer, and a plurality of small pieces divided by the cracks are obtained. Thus, a raw material component having a temporary support and a transfer material layer including a plurality of small pieces formed on the temporary support is obtained. The small pieces are arranged in two directions perpendicular to each other, and are all 3 mm square when observed from the thickness direction.

[0285] (Formation of a Latent Image on the Surface of a Substrate)

[0286] A long film (thickness of 100 μm) formed of a thermoplastic norbornene resin was prepared as a substrate. An adhesive layer was formed in a region of the shape of the letter "T" on the surface of the substrate. Specifically, a commercially available adhesive with adhesive force was cut into the shape of the letter "T", and the cut adhesive layer was attached to the substrate. Thus, a latent image of the letter "T" was formed on the surface of the substrate through the adhesive layer.

[0287] (Formation of Display Layer)

[0288] The substrate and the raw material member on which the latent image is formed are bonded together using a roll-to-roll method while being transported in the length direction. Specifically, the surface of the substrate on the adhesive layer side and the surface of the raw material member on the transfer material layer side are bonded together by clamping rollers. Thereafter, the temporary support body of the raw material member is peeled off. In the area on the substrate where there is no adhesive layer, the small pieces of layers included in the transfer material layer do not remain on the substrate, but are peeled off together with the temporary support body. In the area on the substrate where the adhesive layer is formed, the small pieces of layers included in the transfer material layer remain on the substrate, and only the temporary support body is peeled off. Therefore, on the substrate, in the area in the shape of the letter "T" where the adhesive layer is formed, a plurality of small pieces of layers are selectively provided via the adhesive layer. Moreover, as a collection of these small pieces of layers, a display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, as shown in FIG. Fig. 22 and Fig.23 As shown, a display medium 800 including a substrate 810 and a display layer 830 provided on the substrate 810 via an adhesive layer 820 is obtained.

[0289] [Example 102]

[0290] In the process (production of raw material member), the method of forming the cuts in the liquid crystal solidified layer was changed from the 3 mm square cross-cut method to the following 50 μm square roll pressing method.

[0291] <50μm square roll pressing method>

[0292] In the 50μm square roller pressing method, a plurality of grooves are formed in a straight line in the liquid crystal curing layer using the method described in Example 1 of International Publication No. 2019 / 189246. The grooves are formed at intervals of 50μm in two directions perpendicular to each other. In addition, the depth of the grooves is adjusted in a manner that is deeper than the thickness of the liquid crystal curing layer and does not completely cut off the temporary support. The adjustment of the groove depth is carried out by adjusting the stamping pressure. The multiple small sheet layers of the raw material component obtained by the above-mentioned 50μm square roller pressing method are arranged in two directions perpendicular to each other, and are all squares of 50μm square when observed from the thickness direction.

[0293] Except for the above matters, a display medium having a substrate and a display layer provided on the substrate via an adhesive layer was obtained in the same manner as in Example 101.

[0294] [Example 103]

[0295] In the process (production of raw material member), the method of forming the cuts in the liquid crystal solidified layer was changed from the 3 mm square cross-cut method to the following 20 μm square roll pressing method.

[0296] <20μm square roll pressing method>

[0297] In the 20 μm square roll pressing method, the interval of the cuts was changed from 50 μm to 20 μm, and a plurality of cuts were formed in the liquid crystal solidified layer by the same method as the 50 μm square roll pressing method. The raw material component obtained by the above-mentioned 20 μm square roll pressing method has a plurality of small sheet layers arranged in two directions perpendicular to each other, and all of them are 20 μm square squares when observed from the thickness direction.

[0298] Except for the above matters, a display medium having a substrate and a display layer provided on the substrate via an adhesive layer was obtained in the same manner as in Example 101.

[0299] [Example 104]

[0300] The multilayer component (Q2) manufactured in Manufacturing Example 2 was used instead of the multilayer component (Q1) manufactured in Manufacturing Example 1. In addition, in the process (manufacturing of raw material components), the method of forming the cuts in the liquid crystal solidified layer was changed from the 3 mm square cross-cutting method to the 20 μm square rolling method. Except for the above matters, the same method as Example 101 was used to obtain a display medium having a substrate and a display layer provided on the substrate via an adhesive layer.

[0301] [Examples 105 to 112]

[0302] The multilayer member shown in Table 1 was used instead of the multilayer member (Q1) manufactured in Manufacturing Example 1. In addition, in the process (manufacturing of raw material members), the method of forming a groove in the liquid crystal solidified layer was changed from a 3 mm square cross-cutting method to a 50 μm square rolling method. Except for the above matters, a display medium having a substrate and a display layer provided on the substrate via an adhesive layer was obtained by the same method as in Example 101.

[0303] [Comparative Example 1]

[0304] An adhesive layer is formed on one side of the phase difference film (R2) manufactured in Manufacturing Example 12. Then, the phase difference film (R2) is cut to obtain a film sheet in the shape of a block of the letter "T" with a thickness of approximately 7 mm. The surface of the adhesive layer side of the film sheet and the substrate same as the substrate used in Example 101 are bonded together by batch processing. Thus, a display medium having a substrate and a display layer consisting of a film sheet of a phase difference film (R2) arranged on the substrate via an adhesive layer is obtained.

[0305] [Comparative Example 2]

[0306] A display medium having a display layer consisting of a substrate and a film sheet having a phase difference film (R1) arranged on the substrate via an adhesive layer is obtained by the same method as in Comparative Example 1, except that the phase difference film (R1) manufactured in Manufacturing Example 11 is used instead of the phase difference film (R2) manufactured in Manufacturing Example 12.

[0307] [Comparative Example 3]

[0308] In addition to using the circularly polarized light selective reflection film (D) manufactured in Manufacturing Example 13 instead of the phase difference film (R2) manufactured in Manufacturing Example 12, the same method as Comparative Example 1 is used to obtain a display medium having a substrate and a display layer composed of a film sheet of the circularly polarized light selective reflection film (D) arranged on the substrate via an adhesive layer.

[0309] [Summary of the Configurations of Examples 101 to 112 and Comparative Examples 1 to 3]

[0310] The configurations of Examples 101 to 112 and Comparative Examples 1 to 3 are summarized in the following Table 1. In the following Table 1, the abbreviations have the following meanings.

[0311] Re: In-plane retardation of display layer and patch layer.

[0312] Dispersion: Displays the wavelength dispersion of layers and platelets.

[0313] Reflection color: The color of circularly polarized light reflected by the display layer and small sheet layer with circularly polarized light separation function.

[0314] Reflected polarized light: The rotation direction of the circularly polarized light reflected by the display layer and the small sheet layer with circularly polarized light separation function.

[0315] Shape: The shape of the platelet.

[0316] Size: The width of the flake layer.

[0317] R: Red.

[0318] G: Green.

[0319] B: Blue.

[0320] [Table 1]

[0321] [Table 1. Structure of Examples 101 to 112 and Comparative Examples 1 to 3]

[0322]

[0323] [Observation of Display Media Obtained in Examples 101 to 112 and Comparative Examples 1 to 3]

[0324] The display media obtained in Examples 101 to 112 and Comparative Examples 1 to 3 were observed by observation methods 1 to 4 described later.

[0325] (Observation method 1: Transmitted orthogonal Nicol observation of the display layer)

[0326] Two commercially available linear polarizers are placed in an overlapping manner on a backlight having a fluorescent lamp as a non-polarized light source. The two linear polarizers are placed in an orthogonal Nicol configuration in which the absorption axes are orthogonal to each other when observed from the thickness direction. The display medium obtained by Examples 101 to 105 and Comparative Example 1 is placed between the two linear polarizers. The display medium is set so that the slow axis direction of the display layer and the slow axis direction of the small sheet layer included in the display layer form an angle of 45° with respect to the absorption axis of the linear polarizer. Thereafter, the backlight is turned on, and the light transmitted through the display medium is observed to determine whether the image of the display layer is visible or invisible.

[0327] (Observation method 2: Transmission parallel Nicol observation of the display layer)

[0328] Two commercially available linear polarizers are placed in an overlapping manner on a backlight having a fluorescent lamp as a non-polarized light source. The two linear polarizers are placed in a parallel Nicol configuration in which the absorption axes are parallel to each other when observed from the thickness direction. The display medium obtained by Examples 106 to 107 and Comparative Example 2 is placed between the two linear polarizers. The display medium is set so that the slow axis direction of the display layer and the slow axis direction of the small sheet layer included in the display layer form an angle of 45° with respect to the absorption axis of the linear polarizer. Thereafter, the backlight is turned on, and the light transmitted through the display medium is observed to determine whether the image of the display layer is visible or invisible.

[0329] (Observation method 3: Circular polarizing plate observation of display layer)

[0330] The display medium obtained by Examples 108 to 112 and Comparative Example 3 was irradiated with a fluorescent lamp as a non-polarized light source, and the light reflected by the display medium was observed. As the above-mentioned observation, (i) observation using the naked eye, (ii) observation through a right-handed circular polarizer, and (iii) observation through a left-handed circular polarizer were performed. As the above-mentioned right-handed circular polarizer and left-handed circular polarizer, a right-handed circular polarizer (forward circular polarizer) and a left-handed circular polarizer (reverse circular polarizer) in the shape of glasses used when watching 3D TV were used. During this observation, it was determined whether the image of the display layer was visible or invisible.

[0331] (Observation method 4: observation of small layers)

[0332] The display layer of the display medium is observed (i) with the naked eye and (ii) with a microscope to determine whether the small flake layers included in the display layer are visible or invisible.

[0333] [Results of Examples 101 to 112 and Comparative Examples 1 to 3]

[0334] The results of Examples 101 to 112 and Comparative Examples 1 to 3 are shown in Table 2 below.

[0335] [Table 2]

[0336] [Table 2. Results of Examples 101 to 112 and Comparative Examples 1 to 3]

[0337]

[0338] [Study of Examples 101 to 112 and Comparative Examples 1 to 3]

[0339] As can be seen from Tables 1 and 2, the display layers of the display media obtained in Examples 101 to 105 and Comparative Example 1 are visible when observed with orthogonal Nicols, and the display layers of the display media obtained in Examples 106 to 107 and Comparative Example 2 are visible when observed with parallel Nicols. In addition, the display layers of the display media obtained in Examples 108 to 112 and Comparative Example 3 are visible when observed through one of a right-handed circular polarizer and a left-handed circular polarizer, but are invisible when observed through the other. Therefore, if these display media are used, it is clear that various display characteristics are indeed possessed.

[0340] In particular, the display media obtained in the examples can be manufactured using a low-cost transfer method based on a roll-to-roll process. On the other hand, the display media obtained in the comparative examples cannot be manufactured using a roll-to-roll process and need to be laminated by batch processing, which is disadvantageous in terms of cost.

[0341] In addition, the display layers of the display media obtained in the examples all contain small pieces of uniform shape and arranged in a regular manner, thereby increasing the difficulty of manufacturing and thus increasing the difficulty of counterfeiting. In particular, the display layers of the display media obtained in Examples 102 to 112 cannot be seen by the naked eye, so it is difficult to notice the existence of the small pieces. Therefore, a display medium containing small pieces of layers of small size like this can particularly increase the difficulty of counterfeiting. The effect of increasing the difficulty of counterfeiting like this cannot be obtained by the display media of Comparative Examples 1 to 3 that do not contain small pieces, and is therefore beneficial.

[0342] [Example 201]

[0343] (Manufacturing of base material)

[0344] A colored layer is formed by bonding black paper to the temporary support side of the multilayer structure (CLC_W) manufactured in Manufacturing Example 6, thereby obtaining a long substrate having a colored layer, a support layer as a temporary support, and a liquid crystal solidified layer having a circularly polarized light separation function in sequence.

[0345] (Formation of a Latent Image on the Surface of a Substrate)

[0346] An adhesive layer was formed in a region of the shape of the letter "T" on the surface of the substrate on the liquid crystal cured layer side. Thus, a latent image of the letter "T" was formed on the surface of the substrate through the adhesive layer.

[0347] (Formation of Display Layer)

[0348] The substrate on which the latent image is formed and the raw material component manufactured in Example 102 are bonded together using a roll-to-roll method while being transported in the length direction. Specifically, the surface of the substrate on the adhesive layer side and the surface of the raw material component on the transfer material layer side are bonded together by clamping rollers. Thereafter, the temporary support body of the raw material component is peeled off. On the substrate, in an area in the shape of the letter "T" formed with the adhesive layer, a plurality of small sheet layers are selectively provided via the adhesive layer. Moreover, as a collection of these small sheet layers, a first display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a substrate and a first display layer provided on the substrate via an adhesive layer is obtained.

[0349] [Example 202]

[0350] (Manufacture of Raw Material Member for Forming Second Display Layer)

[0351] The stretching direction of the long film used as a temporary support was changed. In addition, a multilayer component (Q1-1) having a temporary support and a liquid crystal curing layer formed on the temporary support was manufactured using the same method as in Manufacturing Example 1. The in-plane delay Re of the liquid crystal curing layer is 138nm, the thickness of the liquid crystal curing layer is 2.3μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support is 135°. The liquid crystal curing layer has an inverse wavelength dispersion property in which the in-plane delay gradually increases with the increase of the measured wavelength.

[0352] The liquid crystal cured layer of the multilayer member (Q1-1) was scored by a 50 μm square roll press method to obtain a raw material member having a temporary support and a transfer material layer including a plurality of small pieces formed on the temporary support.

[0353] (Formation of Latent Image for Second Display Layer on Surface of Substrate)

[0354] A display medium was manufactured using the same method as in Example 201. An adhesive layer was formed in a region of the shape of the letter "T" on the surface of the first display layer side of the substrate of the display medium. At this time, the adhesive layer was formed so as not to overlap with the first display layer. Thus, a latent image for the second display layer was formed on the surface of the substrate through the adhesive layer.

[0355] (Formation of Second Display Layer)

[0356] The display medium and the raw material component formed with the latent image for the second display layer are transported in the length direction while being bonded using a roll-to-roll method. Specifically, the surface on the adhesive layer side of the display medium and the surface on the transfer material layer side of the raw material component are bonded by a clamping roller. Afterwards, the temporary support body of the raw material component is peeled off. On the substrate, in the area of ​​the shape of the letter "T" formed by the adhesive layer, a plurality of small pieces are selectively provided via the adhesive layer. Moreover, as a collection of these small pieces, a second display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a long substrate and a first display layer and a second display layer provided on the substrate via an adhesive layer is obtained, and the substrate sequentially has a colored layer, a temporary support body, and a liquid crystal curing layer having a circularly polarized light separation function.

[0357] [Example 203]

[0358] (Manufacturing of Raw Material Member for Forming Third Display Layer)

[0359] The stretching direction of the long film used as a temporary support was changed. In addition, a multilayer component (Q1-2) having a temporary support and a liquid crystal curing layer formed on the temporary support was manufactured using the same method as in Manufacturing Example 1. The in-plane delay Re of the liquid crystal curing layer is 138nm, the thickness of the liquid crystal curing layer is 2.3μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support is 180°. The liquid crystal curing layer has an in-plane delay that gradually increases with the increase of the measured wavelength.

[0360] The liquid crystal solidified layer of the multilayer member (Q1-2) was scored by a 50 μm square roll press method to obtain a raw material member having a temporary support and a transfer material layer including a plurality of small pieces formed on the temporary support.

[0361] (Formation of Latent Image for Third Display Layer on Surface of Substrate)

[0362] A display medium was manufactured using the same method as in Example 202. An adhesive layer was formed in a region of the shape of the letter "T" on the surface of the first display layer side of the substrate of the display medium. At this time, the adhesive layer was formed so as not to overlap with either the first display layer or the second display layer. Thus, a latent image for the third display layer was formed on the surface of the substrate through the adhesive layer.

[0363] (Formation of the Third Display Layer)

[0364] The display medium and the raw material component formed with the latent image for the third display layer are transported in the length direction while being bonded using a roll-to-roll method. Specifically, the surface on the adhesive layer side of the display medium and the surface on the transfer material layer side of the raw material component are bonded by a clamping roller. Afterwards, the temporary support body of the raw material component is peeled off. On the substrate, in the area in the shape of the letter "T" formed with the adhesive layer, a plurality of small pieces are selectively provided via the adhesive layer. And, as a collection of these small pieces, a third display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a long substrate and a first display layer, a second display layer, and a third display layer provided on the substrate via an adhesive layer is obtained, and the substrate sequentially has a colored layer, a temporary support body, and a liquid crystal curing layer having a circularly polarized light separation function.

[0365] [Example 204]

[0366] The raw material component manufactured in Example 106 is used instead of the raw material component manufactured in Example 102. In addition, the same method as in Example 201 is used to obtain a display medium having a long substrate and a first display layer arranged on the substrate via an adhesive layer, wherein the substrate has a colored layer, a temporary support body, and a liquid crystal solidification layer having a circularly polarized light separation function in sequence.

[0367] [Example 205]

[0368] (Manufacture of Raw Material Member for Forming Second Display Layer)

[0369] The stretching direction of the long film used as a temporary support was changed. In addition, a multilayer component (H1-1) having a temporary support and a liquid crystal curing layer formed on the temporary support was manufactured using the same method as in Manufacturing Example 4. The in-plane delay Re of the liquid crystal curing layer is 280nm, the thickness of the liquid crystal curing layer is 2.4μm, and the angle formed by the slow axis of the liquid crystal curing layer relative to the long side direction of the temporary support is 135°. The liquid crystal curing layer has a positive wavelength dispersion in which the in-plane delay gradually decreases as the measured wavelength increases.

[0370] The liquid crystal cured layer of the multilayer member (H1-1) was scored by a 50 μm square roll press method to obtain a raw material member having a temporary support and a transfer material layer including a plurality of small sheets formed on the temporary support.

[0371] (Formation of Latent Image for Second Display Layer on Substrate Surface)

[0372] A display medium was manufactured using the same method as in Example 204. An adhesive layer was formed in a region of the shape of the letter "T" on the surface of the first display layer side of the substrate of the display medium. At this time, the adhesive layer was formed so as not to overlap with the first display layer. Thus, a latent image for the second display layer was formed on the surface of the substrate through the adhesive layer.

[0373] (Formation of Second Display Layer)

[0374] The display medium and the raw material component formed with the latent image for the second display layer are transported in the length direction while being bonded using a roll-to-roll method. Specifically, the surface on the adhesive layer side of the display medium and the surface on the transfer material layer side of the raw material component are bonded together by a clamping roller. Afterwards, the temporary support body of the raw material component is peeled off. On the substrate, in the area in the shape of the letter "T" formed with the adhesive layer, a plurality of small pieces are selectively arranged via the adhesive layer. Moreover, as a collection of these small pieces, a second display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a long substrate and a first display layer and a second display layer arranged on the substrate via an adhesive layer is obtained, and the substrate sequentially has a colored layer, a temporary support body, and a liquid crystal curing layer having a circularly polarized light separation function.

[0375] [Example 206]

[0376] The raw material component manufactured in Example 102 is used as the raw material component for the second display layer. In addition, the same method as in Example 205 is used to obtain a display medium having a long substrate and a first display layer and a second display layer arranged on the substrate via an adhesive layer, wherein the substrate sequentially has a colored layer, a temporary support body, and a liquid crystal solidified layer having a circularly polarized light separation function.

[0377] [Example 207]

[0378] (Manufacturing of base material)

[0379] A black paper was laminated on one side of an optically isotropic long film (100 μm thick) made of a thermoplastic norbornene resin to form a colored layer, thereby obtaining a long substrate having a colored layer and a film layer.

[0380] (Formation of a Latent Image on the Surface of a Substrate)

[0381] The adhesive layer is formed in the region of the shape of the letter "T" on the film layer side surface of the substrate. Thus, a latent image of the letter "T" is formed on the surface of the substrate through the adhesive layer.

[0382] (Formation of Display Layer)

[0383] The substrate formed with the latent image and the raw material component manufactured in Example 109 are conveyed in the length direction while being bonded using a roll-to-roll method. Specifically, the surface of the substrate on the adhesive layer side and the surface of the raw material component on the transfer material layer side are bonded by clamping rollers. Thereafter, the temporary support body of the raw material component is peeled off. On the substrate, in an area in the shape of the letter "T" formed with the adhesive layer, a plurality of small sheet layers are selectively provided via the adhesive layer. And, as a collection of these small sheet layers, a first display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a substrate and a first display layer provided on the substrate via an adhesive layer is obtained.

[0384] [Example 208]

[0385] (Formation of Latent Image for Second Display Layer on Surface of Substrate)

[0386] A display medium was manufactured using the same method as in Example 207. An adhesive layer was formed in a region in the shape of a letter "T" on the surface of the first display layer side of the substrate of the display medium. At this time, the adhesive layer was formed so as not to overlap with the first display layer. Thus, a latent image for the second display layer was formed on the surface of the substrate through the adhesive layer.

[0387] (Formation of Second Display Layer)

[0388] The display medium formed with a latent image for the second display layer and the raw material component manufactured in Example 110 are transported in the length direction while being bonded using a roll-to-roll method. Specifically, the surface on the adhesive layer side of the display medium and the surface on the transfer material layer side of the raw material component are bonded by clamping rollers. Thereafter, the temporary support body of the raw material component is peeled off. On the substrate, in an area in the shape of the letter "T" where the adhesive layer is formed, a plurality of small sheet layers are selectively provided via the adhesive layer. Moreover, as a collection of these small sheet layers, a second display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a long substrate including a colored layer and a film layer, and a first display layer and a second display layer provided on the substrate via an adhesive layer is obtained.

[0389] [Example 209]

[0390] The raw material component manufactured in Example 112 is used instead of the raw material component manufactured in Example 109. In addition, the same method as Example 207 is used to obtain a display medium having a long substrate including a colored layer and a film layer, and a first display layer arranged on the substrate via an adhesive layer.

[0391] [Example 210]

[0392] (Formation of Latent Image for Second Display Layer on Surface of Substrate)

[0393] A display medium was manufactured using the same method as in Example 209. An adhesive layer was formed in a region in the shape of a letter "T" on the surface of the first display layer side of the substrate of the display medium. At this time, the adhesive layer was formed so as not to overlap with the first display layer. Thus, a latent image for the second display layer was formed on the surface of the substrate through the adhesive layer.

[0394] (Formation of Second Display Layer)

[0395] The display medium formed with a latent image for the second display layer and the raw material component manufactured in Example 110 are transported in the length direction while being bonded using a roll-to-roll method. Specifically, the surface on the adhesive layer side of the display medium and the surface on the transfer material layer side of the raw material component are bonded by clamping rollers. Thereafter, the temporary support body of the raw material component is peeled off. On the substrate, in an area in the shape of the letter "T" where the adhesive layer is formed, a plurality of small sheet layers are selectively provided via the adhesive layer. Moreover, as a collection of these small sheet layers, a second display layer having the shape of the letter "T" when observed from the thickness direction is formed. Thus, a display medium having a long substrate including a colored layer and a film layer, and a first display layer and a second display layer provided on the substrate via an adhesive layer is obtained.

[0396] [Example 211]

[0397] The raw material component manufactured in Example 105 is used instead of the raw material component manufactured in Example 102. In addition, the same method as in Example 201 is used to obtain a display medium having a long substrate and a first display layer arranged on the substrate via an adhesive layer, wherein the substrate has a colored layer, a temporary support body, and a liquid crystal solidification layer having a circularly polarized light separation function in sequence.

[0398] [Example 212]

[0399] The raw material component manufactured in Example 104 is used instead of the raw material component manufactured in Example 102. In addition, the same method as in Example 201 is used to obtain a display medium having a long substrate and a first display layer arranged on the substrate via an adhesive layer, wherein the substrate has a colored layer, a temporary support body, and a liquid crystal solidification layer having a circularly polarized light separation function in sequence.

[0400] [Comparative Example 4]

[0401] An adhesive layer is formed on one side of the phase difference film (R2) manufactured in Manufacturing Example 12. Then, the phase difference film (R2) is cut to obtain a film sheet in the shape of a block of the letter "T" with a thickness of approximately 7 mm. The surface of the film sheet on the adhesive layer side is bonded to the substrate manufactured in Example 201 by batch processing. Thus, a display medium having a substrate and a first display layer consisting of a film sheet of a phase difference film (R2) arranged on the substrate via an adhesive layer is obtained, and the substrate has a colored layer, a temporary support, and a liquid crystal solidified layer having a circularly polarized light separation function in sequence.

[0402] [Comparative Example 5]

[0403] The phase difference film (R1) manufactured in Manufacturing Example 11 is used instead of the phase difference film (R2) manufactured in Manufacturing Example 12. In addition, the same method as Comparative Example 4 is used to obtain a display medium having a substrate and a first display layer composed of a film sheet of the phase difference film (R1) arranged on the substrate via an adhesive layer, wherein the substrate has a colored layer, a temporary support body, and a liquid crystal solidified layer having a circularly polarized light separation function in sequence.

[0404] [Comparative Example 6]

[0405] An adhesive layer is formed on one side of the circularly polarized light selective reflection film (D) manufactured in Manufacturing Example 13. Then, the circularly polarized light selective reflection film (D) is cut off to obtain a film sheet in the shape of a block of the letter "T" with a thickness of approximately 7 mm. The surface of the film sheet on the adhesive layer side is bonded to the substrate manufactured in Example 207 by batch processing. Thus, a display medium having a substrate including a colored layer and a film layer, and a first display layer consisting of a film sheet of the circularly polarized light selective reflection film (D) provided on the substrate via an adhesive layer is obtained.

[0406] [Summary of the Structures of Examples 201 to 212 and Comparative Examples 4 to 6]

[0407] The configurations of Examples 201 to 212 and Comparative Examples 4 to 6 are summarized in the following Table 3. In the following Table 3, the abbreviations have the following meanings.

[0408] CLC: Liquid crystal curing layer with circularly polarized light separation function.

[0409] Re: In-plane retardation of display layer and patch layer.

[0410] Dispersion: Displays the wavelength dispersion of layers and platelets.

[0411] θ: Angle formed by the slow axes of the display layer and the small platelet layer with respect to the long side direction of the substrate.

[0412] Color: The color of circularly polarized light reflected by the display layer and the small platelet layer having circularly polarized light separation function.

[0413] Reflection: The rotation direction of the circularly polarized light reflected by the display layer and the small sheet layer having the circularly polarized light separation function.

[0414] [Table 3]

[0415] [Table 3. Composition of Examples 201 to 212 and Comparative Examples 4 to 6]

[0416]

[0417] [Observation of Display Media Obtained in Examples 201 to 212 and Comparative Examples 4 to 6]

[0418] The display media obtained in Examples 201 to 212 and Comparative Examples 4 to 6 were observed by observation methods 5 to 8 described later.

[0419] (Observation method 5: Visual observation of display layer)

[0420] The display media obtained in Examples 201 to 212 and Comparative Examples 4 to 6 were irradiated with a fluorescent lamp as a non-polarized light source, and the light reflected by the display media was observed with the naked eye. During the observation, it was determined whether the image of the display layer was visible or invisible.

[0421] (Observation method 6: Observation of the display layer through polarized sunglasses)

[0422] The display medium obtained by Examples 201 to 206, 211, 212 and Comparative Examples 4 to 5 was rotated around the rotation axis in the thickness direction, and irradiated with a fluorescent lamp as a non-polarized light source, and the light reflected by the display medium was observed through a linear polarizer. Commercially available polarized sunglasses were used as linear polarizers. During the above observation, it was determined whether the image of the display layer was visible or invisible. If it could be seen at more than one rotation angle, it was determined to be "visible", and if it could not be seen at all rotation angles, it was determined to be "invisible".

[0423] (Observation method 7: Observation of the display layer under polarized light irradiation)

[0424] The display media obtained in Examples 201 to 203, 211, 212 and Comparative Example 4 were irradiated with linearly polarized light, and the light reflected by the display media was observed with the naked eye. During the above observation, the color of the display layer was determined.

[0425] (Observation method 8: Circular polarizing plate observation of display layer)

[0426] The display medium obtained by Examples 204 to 210 and Comparative Examples 5 to 6 was irradiated with a fluorescent lamp as a non-polarized light source, and the light reflected by the display medium was observed. As the above-mentioned observation, (i) observation through a right-handed circular polarizer and (ii) observation through a left-handed circular polarizer were performed. As the above-mentioned right-handed circular polarizer and left-handed circular polarizer, a right-handed circular polarizer (positive circular polarizer) and a left-handed circular polarizer (reverse circular polarizer) in the shape of glasses used when watching 3D TV were used. During these observations, it was determined whether the image of the display layer was visible or invisible.

[0427] (Observation method 9: observation of small layers)

[0428] The display layer of the display medium is observed (i) with the naked eye and (ii) with a microscope to determine whether the small flake layers included in the display layer are visible or invisible.

[0429] [Results of Examples 201 to 212 and Comparative Examples 4 to 6]

[0430] The results of Examples 201 to 212 and Comparative Examples 4 to 6 are shown in Table 4 below. In the columns of "Naked Eye", "Polarized Sunglasses", "Right-Handed Circular Polarizer", and "Left-Handed Circular Polarizer" in Table 4, the marks "I", "II", and "III" respectively indicate that the first display layer, the second display layer, and the third display layer are visible. In addition, in Table 4 below, not only is it possible to see the image of the display layer by seeing the reflected light from the display layer, but it is also judged that the image of the display layer can be seen by seeing the strong reflected light from the substrate in the area without the display layer, but the reflected light from the display layer cannot be seen or can only be seen weakly.

[0431] [Table 4]

[0432] [Table 4. Results of Examples 201 to 212 and Comparative Examples 4 to 6]

[0433]

[0434] ※1: The first display layer and the second display layer are viewed at different rotation angles.

[0435] ※2: The first display layer, the second display layer, and the third display layer are viewed at different rotation angles.

[0436] ※3: In the second display layer, weak reflected light is observed.

[0437] *4: When the display medium is rotated with the fast axis of the first display layer as the rotation axis, the color of the display layer observed changes depending on the incident angle of the polarized light.

[0438] [Study of Examples 201 to 212 and Comparative Examples 4 to 6]

[0439] As can be seen from Tables 3 and 4, Examples 201 to 203, Example 206, Examples 211 to 212, and Comparative Example 4 are visible when observed with polarized sunglasses. In addition, it is also clear that these samples are visible to the naked eye by irradiating polarized light emitted from the screens of liquid crystal displays and smartphones.

[0440] By comparing Example 201 and Example 211, it is clear that the observed color changes depending on whether the wavelength dispersion of the small piece layer included in the display layer is reverse wavelength dispersion or positive wavelength dispersion.

[0441] By comparing Example 201 and Example 212, it is clear that the angle (tilt angle) formed by the optical axis direction of the small layer included in the display layer relative to the layer plane can give different changes to the observed image in each observation direction.

[0442] In Examples 204 to 205, Examples 207 to 210, and Comparative Examples 5 to 6, it was found that the light was visible or switched between visible and invisible by observation through a circular polarizing plate.

[0443] According to this series of embodiments, it is clear that various display modes can be realized according to different observation methods. Moreover, the display layer of the embodiment sample includes a small layer that is not included in the display layer of the comparative example sample. It can be understood that the difficulty of counterfeiting can be increased by using this small layer.

[0444] Description of Reference Numerals

[0445] 10: Display medium 360U: Surface on the material layer side of the multi-layered component

[0446] 20: Display medium 400: Processing tools

[0447] 30: Display medium 410: Convex part of processing tool

[0448] 100: Base material 410T: Vertex of the convex portion

[0449] 110: Support layer 420: Concave portion of processing tool

[0450] 100U: Surface of substrate 430: End of processing tool

[0451] 200: Display layer 440: End of processing tool

[0452] 210: Crack 450: Support

[0453] 211: Score 500: Processing tools

[0454] 212: Scratches 510: Protrusions of processing tools

[0455] 220: Small piece layer 520: Concave part of processing tool

[0456] 300: Raw material component 530: End of processing tool

[0457] 310: Temporary support 540: End of processing tool

[0458] 310U: Surface of temporary support 550: Support member

[0459] 320: transfer material layer 600: substrate

[0460] 320U: Surface of transfer material layer 610: Colored layer

[0461] 330: small sheet 700: base material

[0462] 340: Crack 710: Select reflective layer

[0463] 340C: Front end of crack 800: Display medium

[0464] 341: Score 810: Base material

[0465] 342: Score 820: Adhesive layer

[0466] 350: Multi-layer component 830: Display layer

[0467] 360: Material Layer

Claims

1. A display medium comprising a substrate and a display layer disposed on the substrate, The display layer includes a plurality of small layers divided into a grid shape by cracks extending in two or more directions. The width of the small piece layer observed in the thickness direction is 100 μm or less, When viewed from the thickness direction, the plurality of small sheet layers are arranged in two or more directions. When viewed from the thickness direction, the small pieces included in the display layer have the same shape.

2. The display medium according to claim 1, wherein: The thickness of the small platelet layer is less than 10 μm.

3. The display medium according to claim 1 or 2, wherein: The small platelet layer is formed of a cured product of a liquid crystal composition.

4. The display medium according to claim 1 or 2, wherein: The in-plane retardation of the small sheet layer at a measurement wavelength of 550 nm is greater than or equal to "{(2n1+1) / 4}×550nm-30nm" and less than or equal to "{(2n1+1) / 4}×550nm+30nm", wherein n1 represents an integer greater than or equal to 0.

5. The display medium according to claim 1 or 2, wherein: The in-plane retardation of the small sheet layer at a measurement wavelength of 550 nm is greater than or equal to "{(2n2+1) / 2}×550nm-30nm" and less than or equal to "{(2n2+1) / 2}×550nm+30nm", wherein n2 represents an integer greater than or equal to 0.

6. The display medium according to claim 1 or 2, wherein: The small sheet layer is one or more selected from a positive A plate, a positive C plate, a tilted O plate and a tilted hybrid orientation plate, wherein the tilted hybrid orientation plate refers to a layer in which the angle formed by the optical axis direction relative to the layer plane is different on one side and the other side of the layer.

7. The display medium according to claim 1 or 2, wherein: The small platelet layer has a function of reflecting a rotation direction D D The circularly polarized light is rotated in the direction D D The wavelength range in which circularly polarized light of opposite rotation direction is transmitted is shown.

8. The display medium according to claim 1 or 2, wherein: The substrate has a selective reflection layer, and the selective reflection layer has a reflection layer capable of reflecting a rotation direction D S The circularly polarized light is rotated in the direction D S Circularly polarized light of opposite rotation direction is transmitted through the substrate reflection range.

9. The display medium according to claim 7, wherein: The substrate has a selective reflection layer, and the selective reflection layer has a reflection layer capable of reflecting a rotation direction D S The circularly polarized light is rotated in the direction D S The reflection range of the substrate through which circularly polarized light of the opposite rotation direction is transmitted. The wavelength width of the substrate reflection range is wider than the wavelength width of the display wavelength range.

10. The display medium according to claim 8, wherein: The wavelength width of the reflection range of the substrate is greater than 70 nm.

11. The display medium according to claim 1 or 2, wherein: The display medium has a plurality of display layers.

12. The display medium according to claim 1 or 2, wherein: The shape of the small platelet layer viewed from the thickness direction is rectangular.

13. The display medium according to claim 1 or 2, wherein: The substrate has a colored layer.

14. The display medium according to claim 1 or 2, wherein: The display medium includes an adhesive layer between the substrate and the display layer.

15. A method for manufacturing a display medium, which is the method for manufacturing a display medium according to any one of claims 1 to 14, comprising the following steps: A step of preparing a raw material member having a temporary support and a transfer material layer, wherein the transfer material layer is formed on the temporary support and includes the small piece layer; forming an adhesive layer on the substrate having the same shape as the display layer when viewed in the thickness direction; A step of laminating the transfer material layer and the adhesive layer; A step of peeling off the temporary support. 16 . A display article comprising a base article and the display medium according to claim 1 disposed on the base article.

Images