Decorative sheet and display device

Abstract

The present application provides a decorative sheet having excellent design. The decorative sheet (20) has a design layer (22) and a transparent resin layer (23) laminated to the design layer (22), and a light-transmitting portion (24) formed as an opening portion of the design layer (22) is provided, and a concavo-convex (20A) is provided on the side of the transparent resin layer (23) opposite to the design layer (22).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a decorative sheet and a display device having the decorative sheet. BACKGROUND

[0002] In order to impart designability to a display device that displays an image light, it is conceivable to provide a decorative sheet facing the display surface of the display device and display an image light on the decorative sheet. The decorative sheet can impart designability to the display device that is coordinated with the surrounding environment. Such a decorative sheet provided to the display device has a light-transmitting portion configured as a fine-pore structure to allow the image light of the display device to be transmitted through the decorative sheet. Patent Literature 1 discloses such a decorative sheet for a display device and a display device with the decorative sheet.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2020-034886 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] In order to suppress scattering of light, the surface of the decorative sheet having the light-transmitting portion is preferably flat. However, the inventors of the present disclosure have conducted intensive studies on a case where a concave-convex structure is formed on the surface of the decorative sheet in order to realize a display device with a decorative sheet that has a variety of textures or tactile sensations and is excellent in designability.

[0008] In view of the above problems, an object of the present disclosure is to provide a decorative sheet and a display device that are excellent in designability.

[0009] MEANS FOR SOLVING THE PROBLEMS

[0010] The decorative sheet of one embodiment of the present disclosure has an appearance design layer and a transparent resin layer layered over the appearance design layer, a light-transmitting portion is configured by providing an opening portion in the appearance design layer, and a concave-convex structure is provided on a surface of the transparent resin layer on the side opposite to the appearance design layer.

[0011] In the decorative sheet, the minimum distance between the surface of the transparent resin layer and the surface of the appearance design layer on the side of the transparent resin layer can be 10 pm or more and 500 pm or less. The value of the haze of the decorative sheet can be 40% or less, the value of the maximum height Pz of the cross-sectional curve of the surface of the transparent resin layer can be 40 pm or less, and the value of the arithmetic mean roughness Ra of the roughness curve of the surface of the transparent resin layer can be 3 pm or less.

[0012] The relief of the decorative sheet can also not have a periodic pattern. Also, in the decorative sheet, the light-transmitting portions and the reliefs can each have a periodic pattern, and when the period of the reliefs of the light-transmitting portions is set as Pa and the period of the pattern of the reliefs is set as P1, the following relationship is satisfied: P1·Pa / |P1-Pa| ≤ 300 μm.

[0013] Also, the decorative sheet can include a diffusion layer laminated with the transparent resin layer, the transparent resin layer being positioned between the diffusion layer and the appearance design layer, and the diffusion layer including particles and a binder resin. The particle diameter of the particles can be less than half the pitch of the reliefs. The particle diameter of the particles can be less than 25% of the pitch of the reliefs. The particle diameter of the particles can be less than 10% of the pitch of the reliefs.

[0014] The transparent resin layer can include a second binder resin and second particles. A portion of the second binder resin can also be positioned in the opening portions. A portion of the second particles can be positioned in the opening portions. The reliefs can also include recesses at positions facing the opening portions.

[0015] In the decorative sheet, the opening ratio can be 10% or more. In the decorative sheet, the period of the pattern of the light-transmitting portions can be 120 μm or less.

[0016] The display device of the present disclosure has an image light emitting device that emits image light, and the decorative sheet that faces the image light emitting device.

[0017] The manufacturing method of the display device of the present disclosure has a step of preparing a decorative panel in which the decorative sheet is laminated to a panel member, and a step of arranging the decorative panel and an image light emitting device that emits image light so as to face each other.

[0018] Effects of the Invention

[0019] The decorative sheet and the display device of the present disclosure are excellent in design. BRIEF DESCRIPTION OF DRAWINGS

[0020] FIG. 1A is a perspective view showing a display device of the present embodiment, showing a state in which the display device is ON.

[0021] FIG. 1B is a perspective view showing a display device of the present embodiment, showing a state in which the display device is OFF.

[0022] FIG. 2 is an exploded perspective view showing a display device of the present embodiment.

[0023] FIG. 3 is a front view showing a display device of the present embodiment.

[0024] FIG. 4 is a longitudinal sectional view showing the display device of the present embodiment, showing FIG. 3 the A-A cross section of

[0025] FIG. 5A is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0026] FIG. 5B is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0027] FIG. 5C is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0028] FIG. 5D is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0029] FIG. 5E is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0030] FIG. 5F is a longitudinal sectional view showing the production process of the decorative sheet of the present embodiment.

[0031] FIG. 6 is a longitudinal sectional view showing the decorative sheet of the present embodiment.

[0032] FIG. 7A is a graph showing the cross-sectional curve of the surface of sample A.

[0033] FIG. 7B is a graph showing the cross-sectional curve of the surface of sample B.

[0034] FIG. 7C is a graph showing the cross-sectional curve of the surface of sample C.

[0035] FIG. 7D is a graph showing the cross-sectional curve of the surface of sample D.

[0036] FIG. 7E is a graph showing the cross-sectional curve of the surface of sample E.

[0037] FIG. 7F is a graph showing the cross-sectional curve of the surface of sample F.

[0038] FIG. 7G is a graph showing the cross-sectional curve of the surface of sample G.

[0039] FIG. 7H is a graph showing the cross-sectional curve of the surface of sample H.

[0040] FIG. 7I is a graph showing a cross-sectional curve of the surface of sample I.

[0041] FIG. 7J is a graph showing a cross-sectional curve of the surface of sample J.

[0042] FIG. 7K is a graph showing a cross-sectional curve of the surface of sample K.

[0043] FIG. 7L is a graph showing a cross-sectional curve of the surface of sample L.

[0044] FIG. 7M is a graph showing a cross-sectional curve of the surface of sample M.

[0045] FIG. 7N is a graph showing a cross-sectional curve of the surface of sample N.

[0046] FIG. 7O is a graph showing a cross-sectional curve of the surface of sample O.

[0047] FIG. 7P is a graph showing a cross-sectional curve of the surface of sample P.

[0048] FIG. 7Q is a graph showing a cross-sectional curve of the surface of sample Q.

[0049] FIG. 8 is a longitudinal sectional view showing a decorative sheet including a diffusion layer.

[0050] FIG. 9 is a longitudinal sectional view showing one modification example of a decorative sheet.

[0051] FIG. 10 is a longitudinal sectional view showing another modification example of a decorative sheet. DETAILED DESCRIPTION

[0052] Hereinafter, one embodiment of the present disclosure (hereinafter, referred to as "the present embodiment") will be described with reference to the drawings. Note that in the drawings attached to this application, the scale of proportion and the ratio of length to width and the like are changed and exaggerated as appropriate in order to facilitate illustration and understanding.

[0053] The decorative sheet 20 and the display device 10 of the present embodiment will be described.

[0054] FIG. 1A is a perspective view showing the display device 10 of the present embodiment, showing a state in which the display device 10 is ON. FIG. 1B is a perspective view showing the display device 10 of the present embodiment, showing a state in which the display device 10 is OFF.FIG. 2 FIG. 1 is an exploded perspective view showing a display device 10 according to the present embodiment. FIG. 3 FIG. 2 is a front view showing the display device 10 according to the present embodiment. FIG. 4 FIG. 3 is a longitudinal sectional view showing the display device 10 according to the present embodiment, showing FIG. 3 an A-A cross section of FIG. 2.

[0055] In order to make the directional relationship clear among the drawings, the same first direction Dl, second direction D2, and third direction D3 are indicated by arrows marked with the same reference numerals in several drawings. The tip side of the arrow becomes the first side of each direction. For example, as shown in FIG. 3 an arrow pointing forward in the direction perpendicular to the plane of the drawing is indicated by a mark provided with a dot in a circle. For example, as shown in FIG. 4 an arrow pointing to the back side in the direction perpendicular to the plane of the drawing is indicated by a mark provided with a cross in a circle.

[0056] The display device 10 at least has an image light emitting device 40 and a decorative sheet 20. In the illustrated example, the display device 10 further has a panel member 30. Further, a decorative panel 50 is constituted by the decorative sheet 20 and the panel member 30.

[0057] The image light emitting device 40 is an arbitrary image display device that emits image light L. The image light emitting device 40 can also display image light L representing a specific icon. The image light emitting device 40 can include a light source device and a light shielding sheet including a light transmitting portion and a light shielding portion. This image light emitting device 40 emits image light L from the light transmitting portion of the light shielding sheet. The image light emitting device 40 can display an icon in a shape corresponding to the shape of the light transmitting portion. The light source device can also be a surface light source device that emits planar light. The surface light source device can be a direct type backlight or an edge light type backlight. The light source device can also be a light source such as an LED. The image light emitting device 40 can also be a liquid crystal display, a plasma display, an organic EL display, or the like.

[0058] The decorative sheet 20 has an appearance design layer 22. The decorative sheet 20 has a light transmitting portion 24 formed as a fine hole structure in the appearance design layer 22 so that image light L from the image light emitting device 40 can transmit through the decorative sheet 20. That is, the light transmitting portion 24 is located in a region of the appearance design layer 22 in which fine holes are provided. In addition, the decorative sheet 20 is provided with a concave-convex 20A based on embossing on its surface, and the decorative sheet 20 is excellent in design. This is one of the features of the decorative sheet 20 according to the present embodiment. The structure of the decorative sheet 20 will be described later in detail.

[0059] The panel member 30 is a transparent member. The panel member 30 is composed of a material that transmits light. The panel member 30 can also be plate-shaped. The panel member 30 constitutes, for example, an interior member or an exterior member of a vehicle such as an automobile or a railway, an aircraft, a ship, and a spacecraft, or the like. As a specific example, the panel member 30 can constitute a center console, a door trim, an instrument panel, or the like of an automobile. The panel member 30 can also constitute an interior member or an exterior member of a building. The panel member 30 can also constitute a member assembled to an electronic device, furniture, or an electric product. As a specific example, the panel member 30 can constitute a touch sensor portion of a television or a monitor, various membrane switches, or the like.

[0060] The material of the panel member 30 is, for example, polycarbonate resin, acrylic resin, ABS resin, or the like. The thickness of the panel member 30 is, for example, 0.5 mm or more and 5 mm or less.

[0061] The display device 10 is configured such that the image light L emitted from the image light emission device 40 is displayed on the image display portion 10a on the surface of the decorative sheet 20 by the decorative sheet 20. The image display portion 10a is a region of the surface of the decorative sheet 20 that directly faces the image light emission device 40 in the third direction D3. As described later, the image display portion 10a displays the image light L from the image light emission device 40 through the light-transmissive portion 24 of the decorative sheet 20.

[0062] In the present specification, a state in which the image light L is not emitted from the image light emission device 40 is set as a state in which the display device 10 is turned off (OFF). A state in which the image light L is emitted from the image light emission device 40 is set as a state in which the display device 10 is turned on (ON).

[0063] In the state in which the display device 10 is OFF, only the appearance design of the decorative sheet 20 is observed, and the presence of the image light emission device 40 is not felt. In the state in which the display device 10 is ON, the image light L emitted from the image light emission device 40 is displayed in the appearance design of the decorative sheet 20, that is, the image display portion 10a on the surface of the decorative sheet 20.

[0064] Thus, the display device 10 having the decorative sheet 20 of the present embodiment has the same design property as a center console or the like of a general automobile in the state in which the display device 10 is OFF, and displays information based on the image light L in the center console or the like in the state in which the display device 10 is ON.

[0065] Next, the structure of the decorative sheet 20 is described in detail.

[0066] As shown in FIG. 1, the decorative sheet 20 has a structure in which the base material layer 21, the design layer 22, and the transparent resin layer 23 are sequentially stacked from the back surface side in the third direction D3. The design layer 22 has a structure in which the shielding layer 222 and the pattern layer 221 are sequentially stacked from the back surface side. In the illustrated example, the decorative sheet 20 also has the transparent resin layer 23 and the surface protective layer 28 which are stacked.

[0067] In the present specification, the side of the decorative sheet 20 which faces the image light projecting apparatus 40, in other words, the side on the third direction D3 which is close to the image light projecting apparatus 40 is set as the back surface side or the lower side. The side opposite thereto, that is, the side on the third direction D3 which is far from the image light projecting apparatus 40, which is visually confirmed by the observer, is set as the front surface side or the upper side. As shown in the drawing, the third direction D3 is the stacking direction of the respective constituent elements. In the illustrated example, the respective constituent elements expand in the first direction D1 and the second direction D2 which are orthogonal to the third direction D3.

[0068] Further, the decorative sheet 20 has the light transmitting portion 24 which is formed as a fine hole structure in the design layer 22. That is, the decorative sheet 20 has the light transmitting portion 24 which is positioned at the opening portion of the design layer 22. The opening portion of the design layer 22 is formed as a non-formed portion of the design layer 22. As shown in the drawing, the light transmitting portion 24 is dispersedly arranged in the design layer 22 when viewed from the front surface side. Further, the light transmitting portion 24 can be formed at least in the region on the surface of the decorative sheet 20 which corresponds to the image display portion 10a. FIG. 3

[0069] The base material layer 21 is a layer which is composed of a transparent film, and appropriately supports the design layer 22 which is stacked with the base material layer 21. The base material layer 21 is composed of a material which transmits visible light and is capable of appropriately supporting the design layer 22.

[0070] The material of the base material layer 21 is, for example, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, cyclic polyolefin, or the like. In addition, the base material layer 21 preferably has a thickness of 10 μm or more and 500 μm or less in consideration of the visible light transmittance, the appropriate support property with respect to the design layer 22, and the like.

[0071] ​Note that, in the present specification, "transparent" means having a degree of transparency that enables viewing of one side of a member from the other side of the member via the member, and for example means having a visible light transmittance of 30% or more, more preferably 50% or more, and further preferably 70% or more. The visible light transmittance is determined as the average value of the total light transmittance at each wavelength when measured at an interval of 1 nm in the range of measurement wavelengths of 380 nm to 780 nm at an incident angle of 0° using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, product in accordance with JIS K 0115).

[0072] The pattern layer 221 is formed in any pattern of a wood grain style, a marble style, a geometric pattern, a carbon style, a stripe, a water drop, a single color, or the like. The pattern layer 221 is composed of a material capable of forming a pattern.

[0073] The material of the pattern layer 221 is, for example, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, a cyclic polyolefin, or the like. The thickness of the pattern layer 221 is, for example, 10 μm or more and 500 μm or less.

[0074] The shielding layer 222 is disposed on the back side of the pattern layer 221 so as to cover the pattern layer 221 from the side on which the image light emitting device 40 is disposed. The shielding layer 222 has a function of absorbing light so as to prevent the image light L from the image light emitting device 40 from being incident into the pattern layer 221. The visible light transmittance of the shielding layer 222 is preferably 80% or less, more preferably 90% or less, and further preferably 95% or less. The shielding layer 222 may, for example, contain light-absorbing particles in an adhesive resin. As the light-absorbing particles, black pigments such as carbon black and titanium black can be exemplified.

[0075] The material of the shielding layer 222 is, for example, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, a cyclic polyolefin, or the like. The thickness of the shielding layer 222 is, for example, 1 μm or more and 20 μm or less.

[0076] The decorative sheet 20 can also not have the shielding layer 222. However, by the presence of the shielding layer 222, it is possible to suppress the incidence of the image light L into the pattern layer 221, and thus it is possible to suppress a case in which the appearance design represented by the pattern layer 221 and the image light L transmitted through the pattern layer 221 are mixed and observed. That is, since the pattern layer 221 absorbs visible light in a specific wavelength region, it is possible to effectively suppress a case in which the color reproducibility of the image deteriorates. Therefore, the decorative sheet 20 can also have the shielding layer 222.

[0077] The transparent resin layer 23 is a layer of a transparent resin in which the concavo-convex 20A based on the embossing is formed on the surface on the front side. The transparent resin layer 23 is composed of a material suitable for embossing.

[0078] The texture of the transparent resin layer 23 can also be configured to correspond to the appearance design of the design layer 22. For example, in the case where the design layer 22 displays a wood grain pattern, recesses or convex portions can be formed in the area where the conduits of the wood grain pattern face each other in the third direction D3. Recesses or convex portions can also be formed in the area where the portion representing the annual rings of the wood grain pattern (summer or autumn material) faces each other in the third direction D3. Recesses or convex portions can also be formed in the area where the nodes of the wood grain pattern face each other in the third direction D3. According to such examples, the combination of the design layer 22 and the transparent resin layer 23 exhibits a natural tactile feel, enhancing the design appeal of the decorative piece 20.

[0079] The transparent resin layer 23 may be made of materials such as polymethyl methacrylate, polyethylene terephthalate, polycarbonate, polyurethane, ABS resin, or polyvinyl chloride. From the viewpoint of heat resistance and abrasion resistance, polymethyl methacrylate, polycarbonate, or ABS resin is preferred. The thickness of the transparent resin layer 23 is, for example, 10 μm or more and 500 μm or less.

[0080] The light-transmitting portion 24 is located at the opening of the appearance design layer 22. The light-transmitting portion 24 allows image light L from the image light emitting device 40 to pass through. FIG. 4 In the example shown, the opening of the appearance design layer 22 is filled with a transparent resin layer 23. The light-transmitting portion 24 is formed by a portion of the transparent resin layer 23.

[0081] exist FIG. 3 In the decorative sheet 20 shown, viewed from the observer's side in the third direction D3, the circular light-transmitting portions 24 are arranged in a grid pattern. That is, the light-transmitting portions 24 are arranged at a fixed spacing in the first direction D1, and also at a fixed spacing in the second direction D2, which is orthogonal to the first direction D1. As an example, the circular light-transmitting portions 24 with a diameter of 80 μm can also be arranged in a square grid pattern with an 80 μm interval. In this example, the proportion (hereinafter referred to as "aperture ratio") of the light-transmitting portions 24 in the image display portion 10a on the surface of the decorative sheet 20 is approximately 20%.

[0082] The opening rate of the decorative sheet 20 is the area ratio of the light-transmitting portions 24 in the decorative sheet 20 when viewed in plan of the decorative sheet 20, that is, in the illustrated example, when viewed from the third direction D3. The opening rate of the decorative sheet 20 can be calculated using the following equation: (opening rate) = (total of areas of light-transmitting portions 24) / (total of areas of appearance design layer 22 + total of areas of light-transmitting portions 24). The opening rate can be measured using a digital microscope VHX-6000 manufactured by KEYENCE Corporation. With respect to the appearance design layer 22 including the shielding layer 222, an enlarged image of the decorative sheet is captured in a state where light is irradiated from the back surface side of the decorative sheet, and a portion where light leaks is determined as an opening portion.

[0083] In a state where the display device 10 is ON, the image light L is transmitted through the light-transmitting portions 24 of the decorative sheet 20 and is observed by an external observer. With respect to the opening rate of the image display portion 10a on the surface of the decorative sheet 20, in order for the observer to be able to observe the image light L to a tolerable degree for practical application as a display device, it is preferable to be 10% or more, in order for the observer to observe the image light L of sufficient brightness, it is preferable to be 15% or more, in order for the observer to observe the image light L of more sufficient brightness, it is further preferable to be 20% or more, it can be 25% or more, and it can be further 30% or more.

[0084] In a state where the display device 10 is OFF, the pattern of the pattern layer 221 of the decorative sheet 20 is observed. With respect to the opening rate of the image display portion 10a on the surface of the decorative sheet 20, in order for the observer to be able to observe the appearance design of the decorative sheet 20 to a tolerable degree for practical application, it is preferable to be 65% or less, in order for the observer to be able to more definitely observe the appearance design of the decorative sheet 20, it is further preferable to be 60% or less.

[0085] In a state where the display device 10 is ON, the image light L is transmitted through the light-transmitting portions 24 of the decorative sheet 20 and is observed by an external observer. With respect to the opening rate of the image display portion 10a on the surface of the decorative sheet 20, in order for the observer to be able to observe the image light L to a tolerable degree for practical application as a display device, it is preferable to be 10% or more, in order for the observer to observe the image light L of sufficient brightness, it is preferable to be 15% or more, in order for the observer to observe the image light L of more sufficient brightness, it is further preferable to be 20% or more, it can be 25% or more, and it can be further 30% or more. FIG. 4 In the illustrated example, the light-transmitting portions 24 are filled with the transparent resin layer 23. That is, the resin forming the transparent resin layer is positioned in the opening portion. According to this structure, in the region of the decorative sheet 20 corresponding to the light-transmitting portions 24, the transparent resin layer 23 is in contact with the base material layer 21. As a result of research by the inventors of the present application, it was found that, if the difference in refractive index between the base material layer 21 and the transparent resin layer 23 is 0.2 or less, the light-transmitting portions 24 become unnoticeable when the decorative sheet 20 is observed closely. It was further found that, by filling the light-transmitting portions 24 with the transparent resin layer 23, scattering of light due to the light-transmitting portions 24, which constitute the opening portions of the appearance design layer 22, and the unevenness of the appearance design layer 22 can be suppressed, and thus the deterioration in the quality of both the appearance design of the decorative sheet 20 and the image light L transmitted through the decorative sheet 20, which are observed by the observer, can be suppressed.

[0086] Note that the decorative sheet 20 of the present embodiment is one in which the light-transmissive portions 24, which are circular in shape, are arranged in a lattice pattern when viewed from the front, but in the decorative sheet 20 of the present disclosure, the light-transmissive portions 24 only need to be formed as openings of the appearance design layer 22, and are not limited to this structure. However, from the viewpoint of suppressing scattering of the image light L and suppressing generation of brightness unevenness in the image light L, the light-transmissive portions 24 of the decorative sheet 20 of the present disclosure are preferably circular in shape, and are preferably arranged in a lattice pattern.

[0087] The surface protective layer 28 is composed of a transparent material, and is a layer for protecting the decorative sheet 20. The material of the surface protective layer 28 is not particularly limited as long as it has such a function. The material of the surface protective layer 28 is, for example, a thermosetting resin such as an acrylic resin, a urethane resin, a phenol resin, a urea melamine resin, an epoxy resin, an unsaturated polyester resin, or a silicone resin, or an ionizing radiation-curable resin such as a compound having an ethylenic unsaturated bond group. The thickness of the surface protective layer 28 is, for example, 1 μm or more and 20 μm or less.

[0088] Next, the manufacturing method of the decorative sheet 20 of the present embodiment will be described.

[0089] FIG. 5A to FIG. 5F is a longitudinal sectional view showing the process of producing the decorative sheet 20 of the present embodiment.

[0090] In the production of the decorative sheet 20, first, as shown in FIG. 5A , the appearance design layer 22 is layered on the base material layer 21. In the example shown in the drawing, the masking layer 222 and the pattern layer 221 are sequentially layered on the base material layer 21. The layering of the appearance design layer 22 onto the base material layer 21 is performed, for example, by printing.

[0091] Next, as shown in FIG. 5B , the openings of the appearance design layer 22, that is, the light-transmissive portions 24, are formed from the pattern layer 221 and the masking layer 222.

[0092] The light-transmissive portions 24 are formed, for example, using a laser technique. In the formation method using the laser technique, first, the appearance design layer 22 is provided on the entire surface of the base material layer 21. Next, laser light is irradiated onto the position on the appearance design layer 22 where the light-transmissive portion 24 is to be formed. The appearance design layer 22 at the position irradiated with the laser light is removed. The position of the appearance design layer 22 that is removed becomes the light-transmissive portion 24.

[0093] The light-transmitting portion 24 can be formed using photolithography. In the photolithography-based formation method, firstly, an appearance design layer 22 is formed on the entire surface of the substrate layer 21. Next, a photoresist is applied to the side where the appearance design layer 22 is formed. Then, a photomask with holes formed at the locations where the light-transmitting portion 24 should be formed is formed is placed on the photoresist. That is, the photoresist is dissolved in the development process at the locations where the light-transmitting portion 24 should be formed. Next, the appearance design layer 22 is removed from the areas where the photoresist has been removed by immersion in an etching solution. The areas where the appearance design layer 22 has been removed become the light-transmitting portion 24.

[0094] Next, as FIG. 5C and FIG. 5D As shown, a transparent resin layer 23 is laminated on the design layer 22. In the illustrated example, the transparent resin layer 23 is formed by heat-laminating a transparent resin film 23a onto the design layer 22. However, the transparent resin layer 23 can also be produced by drying and curing a coating film, not limited to this example.

[0095] Next, as FIG. 5E As shown, a surface protective layer 28 is laminated on the transparent resin layer 23. The lamination of the surface protective layer 28 onto the transparent resin layer 23 is performed, for example, by coating the transparent resin layer 23 with the material of the surface protective layer 28.

[0096] Finally, as FIG. 5F As shown, an embossed pattern 20A is formed on the front side surface of the decorative sheet 20 produced by the above process. In the illustrated example, the embossed pattern 20A is formed on the front side surface of the decorative sheet 20 by passing the heated decorative sheet 20 between an embossing roller 91 and a support roller 92 arranged opposite each other. The embossing roller 91 is, for example, a metal roller with an embossed pattern formed on its surface. The support roller 92 is, for example, a rubber roller.

[0097] Through the above process, decorative sheet 20 can be manufactured. It should be noted that in the example shown, the texture 20A is formed after the transparent resin film 23a is laminated on the appearance design layer 22, but the texture 20A can also be formed on the transparent resin film 23a and then the transparent resin film 23a with the texture 20A is laminated on the appearance design layer 22.

[0098] Next, the features of the concave and convex 20A of the decorative piece 20 formed in this embodiment will be described.

[0099] FIG. 6 This is a longitudinal sectional view showing the decorative piece 20 of this embodiment.

[0100] FIG. 6The shorter the minimum distance D between the upper surface of the transparent resin layer 23 and the upper surface of the appearance design layer 22, the more the scattering of light is suppressed, and the quality of the image light L that transmits through the decorative sheet 20 is improved. However, if the minimum distance D between the upper surface of the transparent resin layer 23 and the upper surface of the appearance design layer 22 is too short, the pattern of the light-transmitting portion 24 is deformed. On the other hand, the longer the minimum distance D between the upper surface of the transparent resin layer 23 and the upper surface of the appearance design layer 22, the more the generation of the Moire fringes described later is suppressed. From this viewpoint, the minimum distance D between the upper surface of the transparent resin layer 23 and the upper surface of the appearance design layer 22 is preferably 10 μm or more and 500 μm or less. In addition, the upper surface of the transparent resin layer 23 is the surface of the transparent resin layer 23 on the opposite side to the appearance design layer 22. In addition, the upper surface of the appearance design layer 22 is the surface of the appearance design layer 22 on the transparent resin layer 23 side.

[0101] The inventors of the present application prepared decorative panels 50 of samples A to Q in order to evaluate the decorative sheets 20 in which the unevenness 20A was formed. The decorative panels 50 were produced by adhering the decorative sheets 20 in which different kinds of unevenness 20A were formed to a polycarbonate having a thickness of 500 μm with an OCA (Optical Clear Adhesive) having a thickness of 50 μm to 100 μm interposed therebetween.

[0102] On the decorative sheet 20, the light-transmitting portions 24 in the shape of a circle having a diameter of 50 μm were arranged in a square lattice shape at a pitch of 120 μm. In addition, the decorative sheet 20 was produced by adhering a polyethylene terephthalate film having a thickness of 50 μm to 70 μm in which the unevenness 20A was formed to a laminate having a thickness of 125 μm composed of the base material layer 21 and the appearance design layer 22 with an OCA having a thickness of 50 μm to 100 μm interposed therebetween.

[0103] The inventors of the present application measured the value of the transmission haze of the samples A to Q. The transmission haze was determined in accordance with JIS K7136 using a haze meter HM-150N (Murakami Color Research Laboratory Co., Ltd.).

[0104] The inventors of the present application measured the Pz (maximum height of cross-sectional curve), Pp (maximum peak height of cross-sectional curve), and Ra (arithmetic mean roughness of roughness curve) of the front surface of Samples A to Q using a stylus-type surface roughness measuring instrument. Pz, Pp, and Ra are defined by JIS B 0601:2013 (ISO 4287:1997, Amd.1:2009). As for the stylus-type surface roughness measuring instrument, Surf-Corder ET4000L manufactured by Shikoku Engineering was used. As for the measurement conditions, the cutoff wavelength was set to 0.8 mm, the cutoff type was set to phase compensation, the measurement speed was set to 0.1 mm / sec, the reference length was set to 0.8 mm, and the evaluation length (measurement length) was set to 4 mm.

[0105] In addition, the inventors of the present application evaluated the visual recognition of transmitted light of Samples A to Q. Specifically, the image light projecting device 40 that projects the image light L indicating a specific icon was arranged on the back surface side of Samples A to Q, and the visual recognition of the image light L displayed on the front surface side by transmitting through Samples A to Q was evaluated. The case where the edge of the icon could be clearly recognized was evaluated as "O", the case where the shape of the icon could be recognized was evaluated as "Δ", and the case where the shape of the icon was largely deformed was evaluated as "X".

[0106] Table 1 shows the results of the measurement and evaluation of Samples A to Q. In addition, FIG. 7A to FIG. 7Q are graphs showing the cross-sectional curves of the surfaces of Samples A to Q, respectively.

[0107] [Table 1]

[0108]

[0109] From the results of the measurement and evaluation of Samples A to Q and the like, it was confirmed that there was a tendency that the smaller the values of the transmitted haze, Pz, and Ra, the better the visual recognition of the image light L. From this viewpoint, the haze of the decorative sheet 20 is preferably 40% or less, more preferably 35% or less, and further preferably 30% or less. The Pz of the surface of the decorative sheet 20 is preferably 40 μm or less, more preferably 35 μm or less, and further preferably 30 μm or less. The Ra of the surface of the decorative sheet 20 is preferably 3 μm or less, more preferably 2.5 μm or less, and further preferably 2 μm or less.

[0110] Furthermore, the inventors of this application have confirmed that moiré patterns may occur between the pattern of the relief 20A and the arrangement pattern of the light-transmitting portion 24. In this embodiment, the light-transmitting portion 24 of the decorative sheet 20 is arranged with a certain periodic pattern. Therefore, when the relief 20A has a periodic pattern, moiré patterns are generated between the periodic pattern of the relief 20A and the periodic pattern of the arrangement of the light-transmitting portion 24. To suppress the generation of these moiré patterns, it is preferable that the relief 20A does not have a periodic pattern, but rather a random pattern.

[0111] Whether the embossed pattern 20A has a periodic pattern can be determined by whether the value obtained by dividing the standard deviation of the inter-peak distance of the cross-sectional curve of the surface of the decorative piece 20 by the average value of the inter-peak distances is less than 10%. That is, if the value obtained by dividing the standard deviation of the inter-peak distance of the cross-sectional curve by the average value of the inter-peak distances is less than 10%, it is determined that it has a periodic pattern. On the other hand, if the value obtained by dividing the standard deviation of the inter-peak distance of the cross-sectional curve by the average value of the inter-peak distances is 10% or more, it is determined that it does not have a periodic pattern. It should be noted that the peaks of the cross-sectional curve are, for example, peaks above Pz on the surface of the decorative piece 20 before the embossed pattern 20A is formed.

[0112] The evaluation of inter-peak distance is performed not only on adjacent peaks, but also on the inter-peak distance between every other peak, every two peaks, and every three peaks. (Refer to...) FIG. 7A The distance between adjacent peaks is, for example, the distance between p1 and p2, p2 and p3, and p3 and p4. The distance between every other peak is, for example, the distance between p1 and p3, p2 and p4, and p3 and p5. The distance between every two peaks is, for example, the distance between p1 and p4, p2 and p5, and p2 and p6. For the distance between peaks that are more than one peak, it is possible to determine the distance between peaks based on... FIG. 7A to FIG. 7Q The evaluation is conducted within the range of the cross-sectional curve shown, up to the interpeak distance every four peaks.

[0113] Table 2, as an example, shows the evaluation results of the peak-to-peak distance of the cross-sectional curves of the surface of the decorative piece 20 for samples D, F, G, H, and M. Table 2 also shows whether moiré fringes were generated. Additionally, regarding sample D, for... FIG. 7D The observation of the right-hand region revealed a finely textured area, which was evaluated.

[0114] [Table 2]

[0115]

[0116] In the samples D, F, and M in which the generation of moire was confirmed, the value obtained by dividing the standard deviation of the peak-to-peak distance of the cross-sectional curve by the average value of the peak-to-peak distance was less than 10%. On the other hand, in the samples G and H in which the generation of moire was not confirmed, the value obtained by dividing the standard deviation of the peak-to-peak distance of the cross-sectional curve by the average value of the peak-to-peak distance was 10% or more.

[0117] Thus, by forming the concavo-convex 20A that does not have a periodic pattern on the decorative sheet 20, the generation of moire can be suppressed.

[0118] In addition, even if moire is generated, as long as the period of the moire is suppressed to a size that cannot be recognized by a person, no practical problem will occur. As for the period Pm (μm) of the moire, the formula Pm = Pl · Pa / |Pl - Pa| is used for the calculation. Pl is the period (μm) of the concavo-convex pattern. As shown in the formula, Pa is the period (μm) of the pattern of the light-transmitting portion 24. As for the size that can be recognized by a person, the formula (size [m] that can be recognized by a person) = 2π / 360 / 60 / (visual acuity) x (distance to the object [m]) can be used for the calculation. FIG. 6

[0119] For example, the size that can be recognized by a person when observing from a distance of 100 cm is about 291 μm for a person with a visual acuity of 1.0. Thus, it can be said that if the period of the moire exceeds 300 μm, the moire is easily observed by a person. From this viewpoint, in the case where the concavo-convex 20A has a periodic pattern, when the period of the concavo-convex pattern is set to Pl and the period of the pattern of the light-transmitting portion 24 is set to Pa, it is preferable that the relationship Pl · Pa / |Pl - Pa| ≤ 300 μm be satisfied.

[0120] As described above, the decorative sheet 20 and the display device 10 of the present embodiment are excellent in design.

[0121] However, in the case where the transparent resin layer 23 having a concavo-convex is used, environmental light from a lighting fixture or the like is scattered due to the concavo-convex 20A of the transparent resin layer 23 when being reflected by the decorative sheet 20. Depending on the shape of the concavo-convex 20A, the scattered light reflected by the transparent resin layer 23 can interfere with each other. Due to the interference of the scattered light, bright and dark portions can be generated on the decorative sheet 20. If bright and dark portions are generated, the visual recognition is reduced. That is, a reduction in the visual recognition caused by the reflected light can occur.

[0122] In addition, in the case where the transparent resin layer 23 having the concavo-convex 20A is used, light irradiated from the back side is scattered due to the pattern of the light-transmitting portion 24. Depending on the shape of the concavo-convex 20A or the like, the light scattered due to the pattern of the light-transmitting portion 24 can interfere with each other. Due to the interference of the scattered light, bright and dark portions can be generated on the decorative sheet 20. That is, a reduction in the visual recognition can occur when the transmitted light is observed.​

[0123] Further, there are cases where the transmitted light scattered due to the pattern of the light-transmitting portion 24 interferes with the reflected light scattered due to the unevenness 20A of the transparent resin layer 23.

[0124] In any of the cases where the visual recognizability is reduced by the reflected light, where the visual recognizability is reduced by the transmitted light, and where the visual recognizability is reduced by the reflected light and the transmitted light, a bright-and-dark pattern in which bright spots of bright luminance and defects of dark luminance are mixed is observed. The bright spots and the defects have sizes that can be observed by an observer of the decorative sheet 20.

[0125] The reduction in the visual recognizability by the reflected light can occur due to the ambient light of a lighting fixture or the like being reflected by the decorative sheet 20. In the bright-and-dark pattern by the reflected light, the bright portions are conspicuous. Since the reduction in the visual recognizability by the reflected light occurs, the appearance design layer 22 is difficult to display the desired appearance design in the state where the display device is OFF, and thus the design property of the appearance design layer 22 can be greatly reduced. Due to the interference of light caused by the scattered reflection at the unevenness 20A of the transparent resin layer 23, a sense of unevenness different from the unevenness 20A of the transparent resin layer 23 can also be seen.

[0126] The reduction in the visual recognizability in the transmitted light observation can occur in the state where the display device is ON. The image light irradiated to the decorative sheet from the back side is scattered due to the pattern of the light-transmitting portion 24. The scattered image light interferes with each other, and thus bright portions and dark portions that are irrelevant to the displayed image are generated. Thus, the visual recognizability of the image is reduced. In the state where the display device is ON, if the displayed image overlaps with the dark portions generated due to the interference of the scattered light, defects are generated in the displayed image, and the visual recognizability of the displayed image is significantly deteriorated.

[0127] In the state where the display device is ON, the ambient light scattered and reflected by the unevenness 20A of the transparent resin layer 23 and the image light L scattered due to the pattern of the light-transmitting portion 24 can interfere with each other. Due to the interference of the ambient light and the image light, the quality of the displayed image can be deteriorated.

[0128] In order to suppress the reduction in the visual recognizability by the reflected light or the reduction in the visual recognizability in the transmitted light observation, as shown in FIG. 8 the decorative sheet 20 can include a diffusion layer 25. The diffusion layer 25 includes particles 26 and a binder resin 27. The binder resin 27 holds the particles 26. The particles 26 are dispersed and held by the binder resin 27. As also confirmed in the examples described later, the reduction in the visual recognizability can be suppressed by the diffusion layer 25.

[0129] It can be assumed that the reduction in visual recognition caused by reflected light is affected by orthogonal reflections directed in a specific direction. Furthermore, it can be assumed that the reduction in visual recognition caused by reflected light is strongly affected by orthogonal reflections on the flat surfaces of the un-roughened transparent resin layer 23. It can be assumed that the reduction in visual recognition during transmitted light observation is caused by a localized and strong change in the optical path of the image light. Based on this presumed reason, it is preferable to make the diffusion in the diffusion layer 25 a more homogeneous diffusion. Therefore, as... FIG. 8 As shown, the particle size W of particle 26 (refer to...) FIG. 8 It can also be smaller than half the spacing P of the unevenness 20A of the transparent resin layer 23. According to this example, it is possible to effectively reduce both the reduction in visual recognition caused by reflected light and the reduction in visual recognition when viewed with transmitted light. The particle size W (μm) of each particle 26 is the maximum length or maximum width of the particle 26 in the cross section of the decorative sheet 20 along the third direction D3.

[0130] If the particle size is too large, the observer will notice the particles. If the particle size is also too large, the particle shape will be reflected in the surface irregularities of the transparent resin layer 23, making it impossible to achieve the desired surface irregularities. Based on these considerations, the particle size W can be less than 25% of the spacing P of the irregularities 20A in the transparent resin layer 23, or less than 10% of the spacing P of the irregularities 20A in the transparent resin layer 23.

[0131] When comparing the particle size W of particle 26 with half the spacing P of the unevenness 20A of transparent resin layer 23, the cross-section of decorative sheet 20 is observed in 10 fields of view at a magnification of 500x to 2000x. The average value of the largest particle size W of particle 26 present in each field of view is determined as the particle size W of particle 26. The spacing P of the unevenness 20A of transparent resin layer 23 is the interval between adjacent protrusions of unevenness 20A. When comparing the particle size W of particle 26 with half the spacing P of unevenness 23, the distance between the tops of two adjacent protrusions is measured at 10 arbitrary locations in the cross-section of decorative sheet 20 along the third direction, and the spacing P of unevenness 20A of transparent resin layer 23 is determined by the average value of these measurements.

[0132] The diffusion layer 25 can be formed by applying a resin composition containing the particles 26 and the binder resin 27 to the concave-convex surface of the transparent resin layer 23 and drying and curing or hardening it. The application of the resin composition can be die coating or spray coating. The material of the binder resin 27 is not particularly limited. The material of the binder resin 27 is, for example, polymethyl methacrylate, polyethylene terephthalate, polycarbonate, polyurethane, ABS resin, polyvinyl chloride, or the like, and polymethyl methacrylate, polycarbonate, or ABS resin is preferred from the viewpoints of heat resistance and wear resistance.

[0133] In order to make the surface of the diffusion layer 25 concave-convex, the thickness of the binder resin 27 can also be thinner than the average particle diameter of the particles 26. The thickness of the binder resin 27 is determined by averaging the thickness of the diffusion layer 25 at 10 positions where the particles 26 are not present. The particles 26 can also contribute to making the surface of the diffusion layer 25 concave-convex. The particles 26 can also form a refractive interface or a reflective interface with the binder resin 27. As the particles 26, metal compounds, porous substances containing gas, resin beads having metal compounds held around them, white fine particles, and simple bubbles can be exemplified.

[0134] In addition, the reduction in visual recognition at the time of transmission light observation can be suppressed by increasing the opening ratio of the decorative sheet 20. Specifically, from the viewpoint of suppressing the reduction in visual recognition at the time of transmission light observation, the opening ratio of the decorative sheet 20 is preferably 10% or more, more preferably 20% or more, and further preferably 30% or more. On the other hand, if the opening ratio of the decorative sheet 20 exceeds 40%, it is difficult to further suppress the reduction in visual recognition at the time of transmission light observation even if the opening ratio of the decorative sheet 20 is increased. Therefore, the opening ratio of the decorative sheet 20 can be 40% or less.

[0135] Furthermore, the reduction in visual recognition at the time of transmission light observation can also be suppressed by the structure of the light-transmitting portion 24 of the decorative sheet 20. Specifically, by reducing the period Pa (see FIG. 6 ) of the pattern of the light-transmitting portion 24, the reduction in visual recognition at the time of transmission light observation can be suppressed. For example, by reducing the period Pa (see FIG. 6 ) of the pattern of the light-transmitting portion 24 while maintaining the opening ratio of the decorative sheet 20, the reduction in visual recognition at the time of transmission light observation can be reduced. The period Pa of the pattern of the light-transmitting portion 24 can be 120 μm or less, 100 μm or less, or 80 μm or less. Therefore, by reducing the planar area of each light-transmitting portion 24 and reducing the interval between two adjacent light-transmitting portions 24, the reduction in visual recognition at the time of transmission light observation can be suppressed while maintaining the opening ratio of the decorative sheet 20.

[0136] Further, from the viewpoint of suppressing the reduction in visual recognizability caused by reflected light and the reduction in visual recognizability at the time of observation of transmitted light, as shown in FIG. 9 The transparent resin layer 23 can include a second adhesive resin 23A and second particles 23B, as shown in FIG. 3. The second adhesive resin 23A holds the second particles 23B. A part of the second adhesive resin 23A is positioned in the opening portion. The second particles 23B are dispersed and held by the second adhesive resin 23A. A part of the second particles 23B is positioned in the opening portion. As also confirmed in the examples described later, the reduction in visual recognizability can be suppressed by the diffusion layer 25. The second adhesive resin 23A can also be the same material as the material of the transparent resin layer 23 described above. The second adhesive resin 23A can also be polymethyl methacrylate, polyethylene terephthalate, polycarbonate, polyurethane, ABS resin, polyvinyl chloride, or the like. The second particles 23B can form a refractive interface or a reflective interface between the second adhesive resin 23A. As the second particles 23B, a metal compound, a porous substance containing gas, a resin bead having a metal compound held around it, white particles, and a simple gas bubble can be exemplified.

[0137] In addition, "second" used in the second adhesive resin 23A and the second particles 23B is used for the purpose of distinguishing from the adhesive resin 27 and the particles 26 of the diffusion layer 25.

[0138] In order to make the diffusion in the transparent resin layer 23 more homogeneous diffusion to suppress the reduction in visual recognizability, the particle diameter of the second particles 23B can also be less than half the pitch P of the concavo-convex of the transparent resin layer 23. When the particle diameter of the second particles 23B is too large, there is a case where the shape of the second particles 23B is reflected on the surface concavo-convex shape of the transparent resin layer 23, and thus the surface concavo-convex shape of the transparent resin layer 23 cannot be made into a desired shape. From these viewpoints, the particle diameter of the second particles 23B can be less than 25% of the pitch P of the concavo-convex 20A of the transparent resin layer 23, and can also be less than 10% of the pitch P of the concavo-convex 20A of the transparent resin layer 23.

[0139] The particle diameter (μm) of each of the second particles 23B is determined in the same manner as the particle diameter of the particles 26 described above. That is, it is the maximum length or the maximum width of the second particles 23B in the cross section of the decorative sheet 20 along the third direction D3. When comparing the particle diameter of the second particles 23B with half the pitch P of the concavo-convex 20A of the transparent resin layer 23, the cross section of the decorative sheet 20 is observed at a magnification of 500 times or more and 2000 times or less in 10 fields of view, and the average value of the particle diameter W of the second particles 23B that becomes the largest in each field of view is determined as the particle diameter W of the second particles 23B.

[0140] Here, we investigated the decrease in visual recognition caused by reflected light and the decrease in visual recognition when observing with transmitted light, and explained the experimental results of this investigation.

[0141] Samples 1-20 were used to create decorative panels. Samples 1-20 comprise a substrate layer 21, an appearance design layer 22, and a transparent resin layer 23. In samples 1-18 and 20, the transparent resin layer 23 was embossed, and the transparent resin layer 23 includes raised and recessed areas 20A. The embossing depth was varied between samples 1-18 and 20. The maximum height Pz of the cross-sectional curve of samples 1-18 and 20 changed. The maximum height Pz of the cross-sectional curve of samples 1-18 and 20 is greater than the maximum height Pz of sample 19, which was not embossed.

[0142] Samples 1-11 also include a diffusion layer 25 covering a transparent resin layer 23. A coating film is formed by spraying a resin composition containing particles 26 and adhesive resin 27 onto the transparent resin layer 23, and then drying the coating film, thereby creating the diffusion layer 25. The created diffusion layer 25 contains particles 26 and adhesive resin 27. Samples 1-3 form diffusion layer A with an average particle size of 4 μm for the particles 26 in the diffusion layer 25, and samples 4-11 form diffusion layer B with an average particle size of 20 μm for the particles 26 in the diffusion layer 25. In samples 12-20, no diffusion layer 25 is provided.

[0143] Between samples 1 and 20, the period (spacing) or size of the light-transmitting portion (opening) in the appearance design layer 22 was changed. For example... FIG. 3 As shown, the light-transmitting portions 24 are arranged regularly in a square pattern. The structures of each sample are shown in Table 3.

[0144] In decorative sheet sample 20, the transparent resin layer 23 comprises a second adhesive resin 23A and a second particle 23B. Sample 20 is manufactured as follows: First, a design layer 22 is formed on the substrate layer 21, similar to other samples. Next, the electron beam curable (EB) resin composition described below is printed onto the design layer by gravure coating. Regarding the coating amount of the electron beam curable (EB) resin composition, the coating amount after drying / curing of the resin composition is 11 g / m². 2 The uncured resin layer was irradiated with an electron beam with an accelerating voltage of 165 kV and an irradiation intensity of 50 kGy (5 Mrad) to cure the electron beam-curable resin composition, thereby producing a transparent resin layer (diffusion layer C) with diffusivity. Then, an embossing process was performed to form an uneven surface on the transparent resin layer with diffusivity.

[0145] [Ionizing radiation-cured resin composition]

[0146] 2 functional urethane acrylate oligomer (weight average molecular weight: 8000): 64 parts by mass

[0147] 6 functional urethane acrylate oligomer (weight average molecular weight: 6000): 16 parts by mass

[0148] Polyurethane beads (spherical shape: particle diameter 3 μm): 20 parts by mass

[0149] [Table 3]

[0150] Structure and evaluation results of samples of Table 3

[0151]

[0152] In the column of "Rugosities" of Table 3, the presence or absence of the rugosities of the transparent resin layer 23 is noted. In the sample 19, no embossing was provided on the transparent resin layer. In the column of "Diffusion layer" of Table 3, the presence or absence of the diffusion layer 25 is noted. In the samples 12 to 20, no diffusion layer 25 different from the transparent resin layer 23 was provided. In the column of "Aperture ratio (%) " of Table 3, the aperture ratio (%) of the decorative sheet 20 is noted. In the column of "Transmissive portion period (μm)" of Table 3, the arrangement pitch Pa (μm) of the light-transmissive portions (aperture portions) of the appearance design layer is noted. In the columns of "Ra (μm)" and "Pz (μm)" of Table 3, the measured values of the arithmetic average roughness Ra (μm) of the roughness curve and the maximum height Pz (μm) of the cross-sectional curve, respectively, are noted in relation to the rugosities 20A of the decorative sheet 20. The "Ra (μm)" and "Pz (μm)" in relation to the samples having the diffusion layer are the measured values on the surface of the diffusion layer.

[0153] The visual recognition of transmitted light was evaluated for each sample. Specifically, an image light emission device 40 was arranged on the back side of samples 1 to 20. The image light emission device 40 included a surface light source device that emits light in a surface shape, and a light shielding panel including a light-transmitting portion and a light-shielding portion. The image light emission device 40 was capable of emitting image light L from the light-transmitting portion of the light shielding panel. The image light emission device 40 was capable of displaying an icon in a shape corresponding to the shape of the light-transmitting portion. The visual recognition of the image light L that was transmitted through samples 1 to 20 and displayed on the surface on the front side was evaluated. The presence or absence of a dark portion caused by interference of transmitted light was confirmed on the icon. For a sample in which no dark portion was observed at all, "A" was noted in the column of "Visual Recognition of Transmitted Light". For a sample in which the presence of a dark portion was noticed if observed carefully, but there was no problem in the visual recognition of the icon, "B" was noted in the column of "Visual Recognition of Transmitted Light". For a sample in which a dark portion was present, but was noticeable with usual attention, but there was no problem in the visual recognition of the icon, "C" was noted in the column of "Visual Recognition of Transmitted Light". For a sample that was a pass level as a product, but a dark portion was present, "D" was noted in the column of "Visual Recognition of Transmitted Light".

[0154] The visual recognition based on reflected light was evaluated for each sample. Specifically, the presence or absence of a bright-dark pattern of a bright portion and a dark portion on samples 1 to 20 was confirmed under a fluorescent lamp. For a sample in which no bright-dark pattern was observed even if the relative position of the fluorescent lamp to the sample or the observation direction of the sample was changed, "A" was noted in the column of "Visual Recognition of Reflected Light". For a sample in which the bright-dark pattern was noticed if observed carefully, but the design property of the design layer was not deteriorated, "B" was noted in the column of "Visual Recognition of Reflected Light". For a sample in which some bright-dark pattern was present, but the design property of the design layer was not deteriorated, "C" was noted in the column of "Visual Recognition of Reflected Light". For a sample that was a pass level as a product, but a bright-dark pattern was present, "D" was noted in the column of "Visual Recognition of Reflected Light".

[0155] Note that in samples 1 to 18 and sample 20, the pitch P of the concave-convex of the transparent resin layer 23 was 160 μm. The particle diameter of the particles contained in the diffusion layer A of samples 1 to 3 was 4 μm. In samples 1 to 3, the particle diameter W of the diffusion layer was 4 μm, which was 2.5% of the pitch P of the concave-convex of the transparent resin layer 23. In samples 4 to 11, the particle diameter W of the diffusion layer B was 20 μm, which was 12.5% of the pitch P of the concave-convex of the transparent resin layer 23. In sample 20, the particle diameter of the second particles 23B of the transparent resin layer 23 was 6 μm, which was 3.75% of the pitch P of the concave-convex of the transparent resin layer 23. In samples 1 to 11 and sample 20, no particles were observed, and there was no case in which the concave-convex shape of the transparent resin layer 23 was greatly disturbed due to the presence of particles.

[0156] The above description describes one embodiment of the present disclosure, but the decorative sheet and display device of the present disclosure are not limited to this embodiment. The decorative sheet and display device of the present disclosure can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the present disclosure. For example, the panel component 30 may be omitted from the display device 10. That is, in the example above, the image light emitting device 40 is stacked with the decorative panel 50, but the image light emitting device 40 may also be stacked with the decorative sheet 20.

[0157] In the above examples, the transparent resin layer 23, the adhesive resin 27, and the second adhesive resin 23A can also be thermoplastic resins. The transparent resin layer 23, the adhesive resin 27, and the second adhesive resin 23A can also be cured products of a curable resin composition. FIG. 10 As shown, in the example of using a cured product of a curable resin composition to prepare a transparent resin layer 23, depending on the curing conditions, unevenness 20A can be formed on the transparent resin layer 23. FIG. 10 In the example shown, a recess 20x is formed with an uneven surface 20A facing the opening of the appearance design layer 22. In the example above, the spacing of the openings 24 is different from the spacing of the uneven surface 20A. FIG. 10 In the example shown, the spacing of the openings 24 is the same as the spacing of the protrusions and recesses 20A. FIG. 10 In the example shown, the embossed 20A can be formed without embossing.

[0158] exist FIG. 9 and FIG. 10 In the example shown, the transparent resin layer 23 contains the second particle 23B. FIG. 9 and FIG. 10 The decorative piece 20 shown may also include a reference. FIG. 8 The diffusion layer 25 is described.

[0159] Label Explanation

[0160] 10: Display device;

[0161] 10a: Image display unit;

[0162] 20: Decorative piece;

[0163] 20S: Sample;

[0164] 20A: Concave / convex;

[0165] 20x: concave part;

[0166] 21: Substrate layer;

[0167] 22: Exterior Design Layer;

[0168] 221: pattern layer;

[0169] 222: shielding layer;

[0170] 23: transparent resin layer;

[0171] 23A: second adhesive resin;

[0172] 23B: second particles;

[0173] 24: light-transmitting portion, opening portion;

[0174] 25: diffusion layer;

[0175] 26: particles;

[0176] 27: adhesive resin;

[0177] 28: surface protective layer;

[0178] 30: panel member;

[0179] 40: image light projecting device;

[0180] 41: image light projecting surface;

[0181] 50: decorative panel;

[0182] 91: embossing roll;

[0183] 92: support roll;

[0184] L: image light.

Claims

1. A decorative sheet, wherein the decorative sheet has a design layer and a transparent resin layer laminated with the design layer, a light-transmitting portion is provided at an opening portion of the design layer, a concavo-convex is provided on a surface of the transparent resin layer on a side opposite to the design layer, the light-transmitting portion and the concavo-convex each have a periodic pattern, when a period of the pattern of the light-transmitting portion is set as Pa and a period of the pattern of the concavo-convex is set as PI, a relation of PI • Pa / |PI - Pa | ≤ 300 μm is satisfied.

2. The decorative sheet according to claim 1, wherein a minimum distance between the surface of the transparent resin layer and a surface of the design layer on a side of the transparent resin layer is 10 μm or more and 500 μm or less.

3. The decorative sheet according to claim 1, wherein a value of a transmittance haze of the decorative sheet is 40% or less, a value of a maximum height Pz of a cross-sectional curve of the surface of the transparent resin layer is 40 μm or less, a value of an arithmetic mean roughness Ra of a roughness curve of the surface of the transparent resin layer is 3 μm or less.

4. The decorative sheet according to any one of claims 1 to 3, wherein the decorative sheet has a diffusion layer laminated with the transparent resin layer, the transparent resin layer is located between the diffusion layer and the design layer, the diffusion layer contains particles and a binder resin.

5. The decorative sheet according to claim 4, wherein a width of the particles of the diffusion layer is less than half of a pitch of the concavo-convex.

6. The decorative sheet according to claim 4, wherein an opening ratio of the decorative sheet is 10% or more.

7. The decorative sheet according to claim 4, wherein a period of the pattern of the light-transmitting portion is 120 μm or less.

8. The decorative sheet according to any one of claims 1 to 3, wherein the transparent resin layer contains a binder resin and particles.

9. The decorative sheet according to claim 8, wherein a part of the binder resin of the transparent resin layer is located within the opening portion.

10. The decorative sheet according to claim 8, wherein a part of the particles of the transparent resin layer is located within the opening portion.

11. The decorative sheet according to claim 8, wherein the concavo-convex contains a concave portion at a position facing the opening portion.

12. A display device, wherein the display device has: an image light emitting device which emits image light; and the decorative sheet according to any one of claims 1 to 11 is disposed opposite to the image light emitting device. ​

Images