Light-emitting display device and fiber sheet with light-shielding layer for use in light-emitting display device

Abstract

This luminescent display device is provided with a luminescent member and a light-blocking layer-equipped fiber sheet for covering a light-emitting face of the luminescent member. The light-blocking layer-equipped fiber sheet comprises a fiber sheet and a light-blocking layer that is printed partially on at least one surface of the fiber sheet. The surface having the light-blocking layer formed thereon has an arithmetic average height Sa of 3-20 μm as measured in accordance with ISO 25178, and has an apparent density of at least 0.5 g / cm3.

Description

[Technical field]

[0001] The present invention relates to a light-emitting display device that displays characters, symbols such as icons, patterns, and images by emitting light from light-emitting members. [Background technology]

[0002] In recent years, light-emitting display devices have been proposed in which the light-emitting components are covered with a light-transmitting sheet, making the presence of the light-emitting components less visible when the light is turned off, and making symbols, patterns, and images such as letters and icons appear on the surface when the light-emitting body of the light-emitting components is turned on.

[0003] For example, the following Patent Document 1 discloses synthetic leather in which a surface layer made of polyurethane resin is laminated on raw cloth, and the visible light transmittance in a portion of the surface in the wavelength range of 380 to 780 nm is 0.10 to 11.90%. Patent Document 1 also discloses that in order to partially form a light-shielding region, cardboard cut into a desired shape is attached, sewn, hooked, welded, or the like to the back side of the raw cloth.

[0004] In addition, the following Patent Document 2 discloses a light-transmitting artificial leather sheet using a transparent or translucent elastomer sheet, characterized in that the back or front of the elastomer sheet is provided with a smoke printed layer, the back of the elastomer sheet, and the outermost layer is provided with a mask printed layer for making letters, figures, patterns, or a design of a combination of these stand out, and the surface of the elastomer sheet is provided with unevenness of a leather pattern.

[0005] Patent Document 3 below discloses a leather-look light-emitting sheet that includes a light-emitting member and a light-transmitting leather-look sheet containing a fiber base material, the light-transmitting leather-look sheet being arranged to cover the light-emitting member, and transmits light emitted from the light-emitting member through a light-transmitting part formed in at least one area of ​​the surface. The sheet also includes a nonwoven fabric of ultrafine fibers having a fineness of 0.8 dtex or less and a polymeric elastomer, and has an apparent density of 0.5 g / cm. 3The above-mentioned fiber base material is preferable because it has excellent dimensional stability due to its denseness, and because it has excellent precision processability when forming a thin-walled portion in a region corresponding to a light-transmitting portion, which is cut thinner than a region corresponding to a non-light-transmitting portion. It is also disclosed that a light-shielding layer is formed by coating a coating liquid containing a colorant on the fiber base material and drying it. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2013-177714 A [Patent Document 2] JP 2014-173203 A [Patent Document 3] JP 2016-081817 A Summary of the Invention [Problem to be solved by the invention]

[0007] As disclosed in Patent Document 3, a fiber sheet with a light-shielding layer obtained by forming a partial light-shielding region in a fiber sheet such as a nonwoven fabric or woven fabric having optical transparency is preferably used in the manufacture of a light-emitting display device that displays characters, icons, and other symbols, patterns, and images by emitting light from a light-emitting member. In order to form a partial light-shielding region in the fiber sheet, a method of forming a light-shielding layer by printing can be considered. According to such a method, a fiber sheet with a light-shielding layer that is preferably used in a light-emitting display device that displays characters, icons, and other symbols, patterns, and images by emitting light can be easily produced.

[0008] However, when a light-shielding layer for forming a light-shielding area was printed on a conventional fiber sheet, uneven application of the ink occurred, making it difficult to form a light-shielding area with little coating unevenness and high light-shielding properties.

[0009] The present invention aims to provide a fiber sheet with a light-shielding layer, which has a light-shielding layer formed by printing and has high light-shielding properties and little coating unevenness, in a light-emitting display device equipped with a fiber sheet with a light-shielding layer formed thereon. [Means for solving the problem]

[0010] One aspect of the present invention is a light-emitting display device including a light-emitting member and a fiber sheet with a light-shielding layer that covers a light-emitting surface of the light-emitting member, the fiber sheet with a light-shielding layer including a fiber sheet and a light-shielding layer that is partially printed on at least one surface of the fiber sheet, the surface of the fiber sheet on which the light-shielding layer is formed has an arithmetic mean height Sa based on ISO25178 of 3 to 20 μm, and the apparent density of the fiber sheet is 0.5 g / cm. 3 The light-emitting display device is as described above. In such a light-emitting display device, when the light-emitting member arranged as the backlight of the fiber sheet with a light-shielding layer is caused to emit light, the light emitted from the light-emitting member is selectively blocked to illuminate and display symbols such as characters and icons, patterns, and images. On the other hand, when the light-emitting member is not emitting light, the light-emitting member is covered and hidden by the fiber sheet. The arithmetic mean height Sa of the surface on which the light-shielding layer is formed is 3 to 20 μm, and the apparent density is 0.5 g / cm 3 With the fiber sheet described above, a light-shielding layer having high light-shielding properties and little coating unevenness can be easily formed by printing.

[0011] Furthermore, when the light-shielding layer is printed on the first surface of the fiber sheet located on the light-emitting surface side, even if the second surface located on the outer surface side has a surface resin layer formed thereon or a raised design surface as described below, the light-shielding layer can be formed on the fiber sheet without affecting the design surface. Furthermore, when the light-shielding layer is printed on the second surface of the fiber sheet not located on the light-emitting surface side, even if the first surface located on the light-emitting surface side is injection-molded to integrate a transparent resin molded body as described below, the printed light-shielding layer is less likely to bleed or flow due to the heat and pressure of injection molding.

[0012] In addition, the fiber sheet with a light-shielding layer is preferably provided with a napped surface on the second surface of the fiber sheet not located on the light-emitting surface side, since it can form the appearance of napped leather such as suede-like leather. In addition, the fiber sheet with a light-shielding layer having a napped surface preferably has a light-transmitting portion with an average light transmittance of 5 to 15%, more preferably 7 to 12%, in the visible light wavelength range of 380 to 780 nm.

[0013] In addition, when the fiber sheet with a light-shielding layer further comprises a surface resin layer having optical transparency on the second surface of the fiber sheet not located on the side of the light-emitting surface, this is preferable because by selecting the design of the surface resin layer, it is possible to impart a luxurious appearance such as a silver-finished leather feel, a wood feel, a stone feel, a metal feel, or the like.

[0014] In addition, when the fiber sheet contains a nonwoven fabric of ultrafine fibers having a fineness of 1 dtex or less and 3 to 40 mass % of a polymeric elastomer impregnated in the nonwoven fabric, the arithmetic mean height Sa is 3 to 20 μm and the apparent density is 0.5 g / cm 3 This is preferable since the fiber sheet having the above properties can be easily obtained.

[0015] Another aspect of the present invention is a fiber sheet with a light-shielding layer used in a light-emitting display device that covers a light-emitting surface of a light-emitting member and selectively transmits light emitted from the light-emitting member to light-emittingly display a symbol, pattern, or image, the fiber sheet having a first surface located on the light-emitting surface side and a second surface located on the outer surface side, and a light-shielding layer partially printed on at least one of the first surface and the second surface, the surface of the fiber sheet on which the light-shielding layer is formed has an arithmetic mean height Sa based on ISO25178 of 3 to 20 μm, and the apparent density of the fiber sheet is 0.5 g / cm. 3 The above is the fiber sheet with a light-shielding layer. Effect of the Invention

[0016] According to the present invention, in a light-emitting display device including a fiber sheet with a light-shielding layer formed thereon, a fiber sheet with a light-shielding layer formed by printing is obtained which has little coating unevenness and has high light-shielding properties. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram of a light-emitting display device 10 including a fiber sheet 3 with a light-shielding layer according to the first embodiment. [Diagram 2] FIG. 2 is a schematic diagram of a fiber sheet 3 with a light-shielding layer. [Diagram 3] FIG. 3 is a schematic diagram of a light-emitting display device 20 including a fiber sheet 13 with a light-shielding layer according to the second embodiment. [Figure 4] FIG. 4 is a schematic diagram of a fiber sheet 13 with a light-shielding layer. [Diagram 5] FIG. 5 is a schematic diagram of a light emitting display device 30 including a fiber sheet 23 with a light blocking layer according to the third embodiment. [Figure 6] FIG. 6 is a schematic diagram of a fiber sheet 23 with a light-shielding layer. [Figure 7] FIG. 7 is a schematic diagram of a light emitting display device 40 including a fiber sheet 33 with a light blocking layer according to the fourth embodiment. [Figure 8] FIG. 8 is a schematic diagram of a fiber sheet 33 with a light-shielding layer. [Figure 9] FIG. 9 is a process schematic diagram of the buffing treatment process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] An embodiment of a light-emitting display device according to the present invention and a fiber sheet with a light-shielding layer used for manufacturing the same will be described.

[0019] FIG. 1 is a schematic diagram of a light-emitting display device 10 of the first embodiment, in which FIG. 1(a) is a schematic plan view showing the light-emitting display device 10 when it is emitting light, and FIG. 1(b) is a schematic cross-sectional view of the II' section of FIG. 1(a).

[0020] Referring to FIG. 1(b), the light emitting display device 10 includes a light emitting member 5 and a fiber sheet 3 with a light-shielding layer that covers the light emitting surface of the light emitting member 5. The light emitting member 5 is a surface light emitting device in which a plurality of light emitting diode devices (LEDs) 5a are mounted on a circuit board 5b. The LEDs 5a of the light emitting member 5 emit light when supplied with power. The light emitting member may be an image display device such as a light emitting display device. The brightness of the light emitting member is preferably 20 to 200 lumens, more preferably 30 to 100 lumens, in order to ensure sufficient display performance while maintaining the concealment properties of the light-shielding layer.

[0021] Fig. 2 is a schematic diagram of a fiber sheet 3 with a light-shielding layer, which constitutes the light-emitting display device 10. Fig. 2(a) is a schematic plan view of the fiber sheet 3 with a light-shielding layer, and Fig. 2(b) is a schematic cross-sectional view taken along the line II-II' in Fig. 2(a).

[0022] The fiber sheet 3 with a light-shielding layer includes a fiber sheet 1 including a fiber structure such as a nonwoven fabric, a woven fabric, or a knitted fabric. , the light emitting member 5 The fiber sheet has a first surface L located on the light-emitting surface side, and a second surface S located on the outer surface side. The second surface S is a napped surface 1a having a suede-like appearance, which is formed by buffing the fibers of the surface layer that forms the fiber sheet 1.

[0023] As shown in Fig. 2(a), in the fiber sheet 3 with a light-shielding layer, a light-transmitting portion D is formed as a partially printed light-shielding layer 2, which allows icon symbols representing the operating states of an audio device, such as stop, play, skip one song, rewind one song, fast forward, and rewind, to stand out. The design of the printed letters, symbols such as icons, patterns, and images can be freely selected depending on the purpose. Note that "partially" means that there is a light-transmitting portion where no light-shielding layer is formed.

[0024] When the first surface L of the fiber sheet 1 is irradiated with light emitted by the light-emitting member 5, the light enters the light-transmitting portion D where no light-shielding layer is formed, passes through the fiber sheet 1, and is emitted from the second surface S. The light transmittance of the fiber sheet 1 is preferably such that the arithmetic mean value of the transmittance in the visible light wavelength range of 380 to 780 nm is 0.1% or more, more preferably 1.0% or more, particularly 5.0% or more, and even more preferably 10% or more. If the arithmetic mean value of the visible light transmittance of the fiber sheet is too low, the luminous characters, symbols, patterns, and images such as icons tend to become unclear. In addition, the light transmittance of the light-shielding layer is preferably such that the arithmetic mean value of the transmittance in the visible light wavelength range of 380 to 780 nm is 0.05% or less, more preferably 0.02% or less.

[0025] As described above, in the fiber sheet 3 with a light-shielding layer, the black light-shielding layer 2 is formed by printing in the area excluding the light-transmitting portion D which is an icon symbol showing the operating state of the audio device. The light-shielding layer 2 is formed by printing on the surface of the fiber sheet 1 with ink such as a pigment ink containing a pigment with high hiding power such as carbon black or titanium oxide and a binder, or a dye ink containing a dark-colored dye with light-shielding power. In the fiber sheet 3 with a light-shielding layer, the arithmetic mean height Sa of the surface of the fiber sheet 1 on which the light-shielding layer 2 is formed is 3 to 20 μm. In addition, the apparent density of the fiber sheet 1 is 0.5 g / cm 3 That's all.

[0026] 1(b), in the light-emitting display device 10, when the LED 5a of the light-emitting member 5 is applied with a current to emit light from the light-emitting surface, the light enters the first surface of the light-shielding layer-attached fiber sheet 3 located on the light-emitting surface side, enters the light-transmitting portion D of the fiber sheet 1 where the light-shielding layer 2 is not formed, passes through the fiber sheet 1, and is emitted from the area of ​​the second surface S, which is the outer surface side, facing the area of ​​the first surface where the light-shielding layer 2 is not formed, as shown by the arrow E. As a result, as shown in FIG. 1(a), an icon explaining the operating state of the audio device appears on the second surface of the outer surface side of the light-shielding layer-attached fiber sheet 3 by the emitted light. When the LED 5a of the light-emitting member 5 is turned off, the icon becomes difficult to see, and the light-emitting member 5 also becomes difficult to see from the outside.

[0027] The fiber sheet with a light-shielding layer may further include a surface resin layer having optical transparency on a second surface of the fiber sheet that is not located on the light-emitting surface side, i.e., on the surface that is the outer surface side of the light-emitting display device. Fig. 3 is a schematic diagram of a light-emitting display device 20 of a second embodiment, which is such a light-emitting display device. Fig. 3(a) is a schematic plan view showing the light-emitting display device 20 when it is emitting light, and Fig. 3(b) is a schematic cross-sectional view of the III-III' cross section of Fig. 3(a).

[0028] 3(b), the light-emitting display device 20 includes a light-emitting member 5 and a fiber sheet 13 with a light-shielding layer that covers the light-emitting surface of the light-emitting member 5. The light-emitting member 5 is similar to the light-emitting member 5 of the first embodiment. Also, FIG. 4 is a schematic diagram of the fiber sheet 13 with a light-shielding layer that constitutes the light-emitting display device 20. FIG. 4(a) is a schematic plan view of the fiber sheet 13 with a light-shielding layer, and FIG. 4(b) is a schematic cross-sectional view of the IV-IV' cross section of FIG. 4(a).

[0029] The light-emitting display device 20 of the second embodiment has a similar configuration to the light-emitting display device 10 of the first embodiment, except that in the light-emitting display device 10 of the first embodiment, a fiber sheet 13 with a light-shielding layer is used in which a surface resin layer 4 having optical transparency is laminated on the second surface of a fiber sheet 11, instead of the fiber sheet 3 with a light-shielding layer, whose second surface, which is not located on the side of the light-emitting surface of the fiber sheet 1, is a suede-like napped surface.

[0030] The fiber sheet with a light-shielding layer may also have a light-shielding layer on a second surface of the fiber sheet that is not located on the light-emitting surface side, i.e., on the surface that is the outer surface side of the light-emitting display device. Fig. 5 is a schematic diagram of such a light-emitting display device 30 of the third embodiment. Fig. 5(a) is a schematic plan view showing the light-emitting display device 30 when it is emitting light, and Fig. 5(b) is a schematic cross-sectional view of the V-V' cross section of Fig. 5(a).

[0031] 5(b), a light-emitting display device 30 of the third embodiment includes a light-emitting member 5 and a fiber sheet 23 with a light-shielding layer that covers the light-emitting surface of the light-emitting member 5. The light-emitting member 5 is similar to the light-emitting member 5 of the first embodiment. Also, FIG. 6 is a schematic diagram of the fiber sheet 23 with a light-shielding layer that constitutes the light-emitting display device 30. FIG. 6(a) is a schematic plan view of the fiber sheet 23 with a light-shielding layer, and FIG. 6(b) is a schematic cross-sectional view of the VI-VI' cross section of FIG. 6(a).

[0032] The light-emitting display device 30 of the third embodiment has a similar configuration to the light-emitting display device 20 of the second embodiment, except that, instead of the light-shielding layer 2 being formed on the first surface located on the light-emitting surface side of the fiber sheet 11 in the light-emitting display device 20 of the second embodiment, a fiber sheet 23 with a light-shielding layer is used in which a light-shielding layer 12 is formed on a second surface that is not located on the light-emitting surface side of the fiber sheet 11.

[0033] 5 and 6, in the light-emitting display device 30 of the third embodiment using the fiber sheet 23 with a light-shielding layer in which the light-shielding layer 12 is formed on the second surface of the fiber sheet 11 that is not located on the light-emitting surface side, the light-shielding layer 12 is formed in a position close to the outer surface of the fiber sheet 11, so that the outline of the emitted light E is sharp. 1 or 11 Because of internal diffusion, the contour of the emitted light E tends to be slightly less clear than in the light emitting display device 30 of the third embodiment.

[0034] The light-emitting display device 40 of the fourth embodiment is the same as the light-emitting display device 20 of the third embodiment, except that a light-shielding layer 2 is formed on a first surface located on the light-emitting surface side of the fiber sheet 11, and To11 A fiber sheet with a light-shielding layer, in which a light-shielding layer 12 is also formed on a second surface not located on the light-emitting surface side. To 33 Except for this, the light emitting display device has the same configuration as the light emitting display device 20 of the second embodiment.

[0035] As shown in Figs. 7 and 8, a light-emitting display device 40 of the fourth embodiment using a fiber sheet 33 with a light-shielding layer in which a light-shielding layer 12 is formed on both a first surface located on the light-emitting surface side of a fiber sheet 11 and a second surface not located on the light-emitting surface side realizes the following light emission. The first surface enhances the directivity of incident light by the light-shielding layer 2. Also, by forming the light-shielding layer 12 on the second surface close to the outer surface as in the light-emitting display device 30 of the third embodiment, the outline of the emitted light E becomes clearer than that of the light-emitting display device 30. Also, if the light-shielding layer on the first surface and the light-shielding layer on the second surface are designed differently from each other, a more flexible design is possible.

[0036] The basic configuration of the light-emitting display device according to the first to fourth embodiments has been outlined above. Next, the light-shielding layer-attached fiber sheet, which is a feature of the light-emitting display device according to each embodiment, will be described in detail along with its manufacturing method.

[0037] The fiber sheet used in the manufacture of the fiber sheet with a light-shielding layer contains a fiber structure such as a nonwoven fabric, a woven fabric, or a knitted fabric, and if necessary, the voids in the fiber structure are impregnated with a polymeric elastomer. Among the fiber structures, nonwoven fabrics, particularly nonwoven fabrics made of ultrafine fibers with a fineness of 1 dtex or less, are preferred. Nonwoven fabrics made of ultrafine fibers can easily increase the fiber density and thus the apparent density, and can easily reduce unevenness in fiber density and thus make the surface smooth. Below, a detailed description is given of a typical example of a case in which a fiber base material containing a nonwoven fabric made of ultrafine fibers is used.

[0038] A nonwoven fabric of ultrafine fibers can be obtained by, for example, entangling ultrafine fiber-generating fibers such as islands-in-sea (matrix-domain) composite fibers and then subjecting them to ultrafine fiber processing. In this embodiment, the use of islands-in-sea composite fibers will be described in detail. Instead of islands-in-sea composite fibers, ultrafine fiber-generating fibers other than islands-in-sea composite fibers may be used, or ultrafine fibers may be spun without using ultrafine fiber-generating fibers. Specific examples of ultrafine fiber-generating fibers other than islands-in-sea composite fibers include peel-split fibers formed by lightly bonding multiple ultrafine fibers immediately after spinning and then mechanically untangling the fibers to form multiple ultrafine fibers, and petal-shaped fibers formed by alternately assembling multiple resins in a petal-like shape in a melt spinning process.

[0039] In the production of a nonwoven fabric of ultrafine fibers, first, a thermoplastic resin constituting the sea component (matrix component) of the islands-in-sea type composite fiber, which is to be selectively removed, and a thermoplastic resin constituting the island components (domain components) of the islands-in-sea type composite fiber, which is the resin component forming the ultrafine fibers, are melt spun and drawn to produce islands-in-sea type composite fibers.

[0040] The thermoplastic resin for the sea component is selected from those having different solubility in solvents or decomposability in decomposers from those of the island component.Specific examples of the thermoplastic resin for the sea component include water-soluble polyvinyl alcohol resins, polyethylene, polypropylene, polystyrene, ethylene propylene resins, ethylene vinyl acetate resins, styrene ethylene resins, and styrene acrylic resins.

[0041] The thermoplastic resin, which is a resin component forming island components and ultrafine fibers, is not particularly limited as long as it is a resin capable of forming islands-in-the-sea composite fibers and ultrafine fibers. Specific examples include aromatic polyesters such as polyethylene terephthalate (PET), isophthalic acid-modified PET, sulfoisophthalic acid-modified PET, polybutylene terephthalate, and polyhexamethylene terephthalate; aliphatic polyesters such as polylactic acid, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, and polyhydroxybutyrate-polyhydroxyvalerate resin; polyamides such as polyamide 6, polyamide 66, polyamide 10, polyamide 11, polyamide 12, and polyamide 6-12; and polyolefins such as polypropylene, polyethylene, polybutene, polymethylpentene, and chlorine-based polyolefins. These may be used alone or in combination of two or more.

[0042] Examples of methods for producing nonwoven fabrics of ultrafine fibers include a method in which islands-in-sea composite fibers are melt-spun to produce a web, the web is entangled, and then the sea component is selectively removed from the islands-in-sea composite fibers to form ultrafine fibers. Examples of methods for producing a web include a method in which islands-in-sea composite fibers of long fibers spun by a spunbonding method or the like are collected on a net without being cut to form a long fiber web, and a method in which the long fibers are cut into staples to form a short fiber web. Among these, a long fiber web is particularly preferred because it is easy to increase the fiber density and therefore the apparent density, and it is easy to reduce unevenness in fiber density and thus to make the surface smooth. The formed web may also be subjected to a fusion treatment to impart shape stability.

[0043] Here, the term "long fibers" means continuous fibers that are not short fibers that are intentionally cut after spinning. More specifically, it means fibers that are not short fibers that are intentionally cut to a fiber length of about 3 to 80 mm, for example. The fiber length of the islands-in-sea type composite fiber before being made into ultrafine fibers is preferably 100 mm or more, and may be several meters, several hundred meters, several kilometers, or even longer, as long as it is technically possible to produce it and it is not unavoidably cut during the production process. Note that, in some cases, the long fibers are inevitably cut into short fibers during the production process due to needle punching during entanglement or surface buffing, which will be described later.

[0044] In any step from removing the sea component of the islands-in-sea type composite fiber to forming the ultrafine fibers, the islands-in-sea type composite fiber can be densified by carrying out an entanglement treatment and a fiber shrinkage treatment such as a heat shrinkage treatment with water vapor. As the entanglement treatment, for example, a method of stacking about 5 to 100 sheets of web and subjecting them to needle punching or high-pressure water jet treatment can be mentioned.

[0045] The sea component of the islands-in-sea type composite fiber is dissolved or decomposed and extracted and removed at an appropriate stage after the formation of the web. The islands-in-sea type composite fiber is converted into ultrafine fibers by such decomposition and removal or dissolution and removal, and a nonwoven fabric of ultrafine fibers in the form of fiber bundles is formed. The apparent density of the nonwoven fabric of ultrafine fibers in the form of fiber bundles may be further increased by heat shrinking treatment, heating roll or hot pressing.

[0046] The fineness of the ultrafine fibers is not particularly limited, but a fineness of 1 dtex or less, preferably 0.01 to 0.6 dtex, and particularly preferably 0.02 to 0.5 dtex, is preferred because the fiber density of the ultrafine fibers tends to be high, resulting in a high apparent density, which makes it easier for the ink for printing the light-shielding layer to penetrate into the fiber sheet due to capillary action.

[0047] In the gaps between the fibers of the fiber structure such as nonwoven fabric, a polymeric elastomer may be contained as necessary for the purpose of imparting shape stability or a feeling of fullness. The type of polymeric elastomer is not particularly limited. Specific examples thereof include various polyurethanes such as polycarbonate-based polyurethane, polyester-based polyurethane, and polyether-based polyurethane; acrylic elastomers; polyurethane-acrylic composite elastomers; polyvinyl chloride; synthetic rubber, etc. Among these, polyurethane is preferred because of its excellent adhesiveness and mechanical properties.

[0048] A method of applying a polymeric elastomer to a fiber structure such as a nonwoven fabric includes a method of impregnating a fiber structure with a solution or emulsion of a polymeric elastomer and then solidifying the polymeric elastomer. A preferred method of impregnating a fiber structure with a solution or emulsion of a polymeric elastomer is a dip-nip method in which the fiber structure is immersed in the solution or emulsion so as to reach a predetermined impregnation state, and the solution or emulsion is squeezed with a press roll or the like once or multiple times. Other methods that may be used include a bar coating method, a knife coating method, a roll coating method, a comma coating method, and a spray coating method.

[0049] The polymeric elastomer can be applied to the fiber structure by impregnating the fiber structure with a solution or emulsion of the polymeric elastomer and then solidifying the polymeric elastomer.

[0050] The content of the polymer elastomer in the fiber sheet is preferably 3 to 40 mass%, further preferably 8 to 35 mass%, and particularly preferably 12 to 30 mass%, because increasing the fiber density increases the apparent density of the fiber sheet, and the ink for printing the light-shielding layer is more easily absorbed due to capillary action.

[0051] In this manner, the fiber sheet substrate is obtained. If necessary, the thickness of the obtained fiber sheet substrate is adjusted by slicing or buffing.

[0052] The fiber sheet substrate is then further pressed to adjust the apparent density. Specifically, the fiber sheet substrate is pressed at room temperature or hot-pressed to reduce voids in the fiber sheet substrate and increase the fiber density of the fiber structure. There are no particular limitations on the pressing means, but a manual press or roll press is preferably used.

[0053] When pressing, the pressing pressure is preferably 5 to 20 MPa, more preferably about 8 to 15 MPa, from the viewpoint of maintaining the quality of the appearance. When using a heat press, the setting temperature of the heating roll is preferably 100 to 150°C, more preferably 110 to 120°C, from the viewpoint of maintaining the quality of the appearance.

[0054] In this way, the apparent density of the base material of the fiber sheet is adjusted. The apparent density of the fiber sheet after pressing is 0.50 g / cm 3 or more, 0.50 to 0.95 g / cm 3 , especially 0.50~0.90g / cm 3 It is preferable that the apparent density of the fiber sheet after pressing is 0.50 g / cm. 3 If the fiber density is less than 1 / 2 mm, the ink for printing the light-shielding layer will not penetrate into the thickness direction due to capillary action and will tend to diffuse in the surface direction due to the low fiber density, making it difficult to uniformly apply the ink so as to form a light-shielding layer with high light-shielding properties and little coating unevenness.

[0055] In addition, in order to smooth the surface of the fiber sheet substrate on which the light-shielding layer is printed, it is preferable that the surface of the fiber sheet substrate on which the light-shielding layer is printed is smoothed by buffing.

[0056] An example of a buffing process for smoothing the surface on which the light-shielding layer is to be printed is a method in which a rotating buff roller, the surface of which is covered with sandpaper, is brought into contact with the surface of the fiber sheet substrate on which the light-shielding layer is to be printed, thereby performing a grinding process. By this buffing process, the surface of the fiber sheet substrate on which the light-shielding layer is to be printed is smoothed.

[0057] 9 shows an example of a process schematic diagram of a buffing process using a buffing device 100 for buffing a surface N of a fiber sheet substrate 50 on which a light-shielding layer is printed. As shown in FIG. 9, the buffing device 100 has a delivery roller 111 that delivers the substrate 50, a take-up roller 112 that takes up the substrate 50, a pressure roller 113, a buff roller 114, a drive roller 115, and an abrasive belt 116. The substrate 50 moves in a direction toward the take-up roller 112. Towards A Being transported.

[0058] The polishing belt 116 is a circular belt whose surface is sandpaper, and is stretched between the buff roller 114 and the drive roller 115. A rotary drive motor that rotates a shaft (not shown) is connected to the drive roller 115, and the rotation of the shaft rotates the drive roller 115, thereby rotating the polishing belt 116 that is stretched between the buff roller 114 and the drive roller 115.

[0059] Buff roller 114 and pressure roller 113 are disposed to face each other across base material 50. Pressure roller 113 is a rubber roller with a smooth peripheral surface. Pressure roller 113 presses base material 50 in direction D. Pressure roller 113 rotates in direction C, and buff roller 114 rotates in direction B.

[0060] The substrate 50 is sent out in a direction A from the send-out roller 111 towards the take-up roller 112 while being subjected to tension. Then, the substrate 50 is sent out from the send-out roller 111 and taken up by the take-up roller 112. During the process from sending out to taking up, the substrate 50 is subjected to a buffing process by bringing sandpaper of a rotating abrasive belt 116 stretched around a buff roller 114 into contact with the surface N of the substrate 50 on which the light-shielding layer is to be printed.

[0061] The polishing belt 116 has sandpaper on its outer periphery, to which fine abrasive grains of, for example, about #120 to #600 are fixed.

[0062] The load current applied to the buff roller 114 is adjusted by adjusting the pressure in the direction D applied to the surface N of the substrate 50 on which the light-shielding layer is printed, between the pressure roller 113 and the buff roller 114. If the load current is too low or too high, it becomes difficult to operate with a stable current value.

[0063] The rotation speed of the buff roller 114 depends on the diameter of the buff roller and the grit of the sandpaper, but is preferably 300 to 1500 rpm, and more preferably 300 to 1000 rpm. The conveying speed of the substrate 50 also depends on the diameter of the buff roller and the grit of the sandpaper, but is preferably 2 to 10 m / min, and more preferably 3 to 6 m / min.

[0064] When the substrate 50 delivered from the delivery roller 111 is buffed, the shear force that the abrasive belt 116 applies to the surface N of the substrate 50 on which the light-shielding layer is to be printed is adjusted by changing the rotation speed and load current of the buff roller 114, and the transport speed of the substrate 50. When the rotation speed, current value, and transport speed of the buff roller 114 are high, the shear force becomes large, and when they are low, the shear force becomes small.

[0065] The buffing process described above smoothes the surface of the fiber sheet on which the light-shielding layer is to be printed. The surface of the fiber sheet on which the light-shielding layer is to be formed, adjusted in this manner, has an arithmetic mean height Sa based on ISO25178 of 3 to 20 μm, preferably 3 to 12 μm. The arithmetic mean height (Sa) based on ISO25178 is a parameter that represents the average of the absolute values ​​of the differences in height of each point with respect to the average plane of the surface.

[0066] If the arithmetic mean height Sa of the surface of the fiber sheet on which the light-shielding layer is formed exceeds 20 μm, the surface on which the light-shielding layer is printed becomes too fluffy and lacks smoothness, and the ink does not adhere accurately to the printed surface during printing, leading to the ink diffusing and resulting in an uneven thickness of the light-shielding layer that is formed, resulting in uneven light emission. Also, if the arithmetic mean height Sa of the surface of the fiber sheet on which the light-shielding layer is formed is less than 3 μm, the anchor effect is less likely to work after the ink is applied, and the ink adhesion decreases.

[0067] In this way, a fiber sheet for forming a light-shielding layer is obtained. The thickness of the fiber sheet is appropriately adjusted depending on the desired visible light transmittance and the application, but is preferably 0.1 to 3 mm, more preferably 0.15 to 1 mm, and particularly preferably 0.2 to 0.9 mm. If the fiber sheet is too thick, the light transmittance tends to decrease.

[0068] Then, by printing a light-shielding layer on the surface of the obtained fiber sheet, the surface having an arithmetic mean height Sa adjusted to 3 to 20 μm, a fiber sheet with a light-shielding layer is obtained, which is used in a light-emitting display device that covers the light-emitting surface of a light-emitting component and selectively transmits the light emitted from the light-emitting component to illuminate and display symbols such as letters and icons, patterns, and images.

[0069] The light-shielding layer is formed by printing, with ink, characters, icons, and other symbols, patterns, and images to be luminescently displayed on the surface of the fiber sheet, the arithmetic mean height Sa of which is adjusted to 3 to 20 μm. Printing methods used to print the light-shielding layer include screen printing, gravure printing, and inkjet printing. Among these, screen printing is preferred because it is a relatively inexpensive process that can stably apply the light-shielding layer and is excellent in terms of mass printing productivity.

[0070] The ink used to print the light-shielding layer may be a pigment ink containing a highly opaque pigment such as carbon black or titanium oxide and a binder such as an acrylic resin, or a dye ink containing a dark-colored dye. The viscosity of the ink used for printing is designed to be within a preferred range depending on the printing method, but in the case of screen printing, it is preferable for the viscosity of the coating ink diluted with a solvent to be around 10 to 100 Pa·sec in order to allow adequate penetration into the fiber sheet.

[0071] The thickness of the light-shielding layer thus formed is preferably from 5 to 80 μm, and more preferably from about 20 to 50 μm.

[0072] As shown in the light emitting display device 20 of the second embodiment and the light emitting display device 30 of the third embodiment, a surface resin layer 4 having optical transparency may be formed on the second surface of the fiber sheet 11.

[0073] The surface resin layer 4 is a resin layer having optical transparency for imparting a luxurious design appearance such as a silver-finished leather feel, a wood texture, a stone texture, a metal texture, etc. By laminating and forming a surface resin layer having optical transparency on the second surface of the fiber sheet 11, which is the outer surface side and not located on the light-emitting surface side, it is possible to impart to the light-emitting display device an appearance having a luxurious design surface such as a silver-finished leather feel, a wood texture, a stone texture, a metal texture, etc.

[0074] Examples of methods for forming a surface resin layer include a method of forming a resin layer containing a polymeric elastomer having optical transparency such as polyurethane on the surface of a fiber sheet by a dry surface forming method or a direct coating method. The dry surface forming method is a method of forming a resin film containing a polymeric elastomer on a support substrate such as a release paper, applying an adhesive to the surface of the resin film, attaching it to the surface of a fiber sheet, pressing it to adhere it as necessary, and peeling off the release paper to form a surface resin layer having optical transparency. The direct coating method is a method of forming a surface resin layer by directly applying a liquid resin or a resin liquid containing a polymeric elastomer to the surface of a fiber sheet and then curing it.

[0075] As the polymeric elastomer for forming the surface resin layer, polyurethane, acrylic elastomer, etc. can be used. The surface resin layer is selected from those having light transmittance. The type of polymeric elastomer for forming such a surface resin layer is not particularly limited. Specific examples thereof include various polyurethanes such as polycarbonate polyurethane, polyester polyurethane, and polyether polyurethane; acrylic elastomer; polyurethane-acrylic composite elastomer; polyvinyl chloride elastomer; synthetic rubber, etc. These polymeric elastomers may be used alone or in combination of two or more. Among these, polyurethane is preferred because of its excellent mechanical properties such as abrasion resistance and bending resistance. The thickness of the surface resin layer is not particularly limited, but is preferably about 20 to 200 μm, for example. The surface resin layer may be formed so that the nap of the fiber sheet coexists.

[0076] The light transmittance of the surface resin layer is preferably such that the visible light transmittance of the light transmitting portion of the fiber sheet with a light-shielding layer is 0.1% or more, preferably 1.0% or more, particularly 5.0% or more, and even more preferably 10% or more.

[0077] The configuration of the light-emitting display device described above can be appropriately modified depending on the purpose and use. Specifically, for example, a transparent resin molded body may be integrated with the surface layer of the first surface on the light-emitting surface side of the fiber sheet. Specifically, the fiber sheet with a light-shielding layer may be disposed in a cavity of an in-mold molding die so that the second surface not located on the light-emitting surface side faces the cavity surface, and a transparent resin may be injected into the cavity by injection molding to integrate a transparent resin molded body having optical transparency with the first surface on the light-emitting surface side.

[0078] The light emitting devices according to the embodiments described above can form surfaces for illuminating and displaying in the interiors of home appliances, automobiles, aircraft, ships, buildings, and the like. EXAMPLES

[0079] The present invention will be described in more detail below with reference to examples, although the scope of the present invention is not limited to these examples in any way.

[0080] First, the evaluation methods used in the present examples will be summarized below.

[0081] (arithmetic mean height Sa) The arithmetic mean height Sa of the printed surface of the light-shielding layer of the fiber sheet, which conforms to ISO 25178, was measured using the non-contact surface roughness and shape measuring instrument "Digital microphone The measurements were made using a "Roscope VHX-6000" (Keyence Corporation). Specifically, the printed surface of the light-shielding layer of the fiber sheet was brushed ten times in the grain direction with a polyester lint brush (Etiquette Brush (registered trademark) manufactured by Nippon Seal Co., Ltd., commonly known as Seal Brush), and a distorted fringe projection image was taken at 100x magnification with a 4 megapixel monochrome C-MOS camera using structured illumination light irradiated from a high-brightness LED over an 18mm x 24mm area of ​​the brushed surface. The images obtained were then analyzed to determine the arithmetic mean height (Sa). The measurements were made three times, and the average values ​​were used for each value.

[0082] (Apparent density) According to JIS L 1913, thickness (mm) and basis weight (g / m 2 ) and calculate the apparent density (g / cm 3 ) was calculated.

[0083] (fineness) The fineness was determined by taking a scanning electron microscope (SEM) photograph of the cross-section of the raised nap artificial leather at 3,000x magnification, randomly selecting 10 fiber cross-sections to measure their cross-sectional area, calculating the average cross-sectional area, and converting it into the density of each resin.

[0084] (light transparency) The light transmittance of the light-transmitting portion of the fiber sheet was evaluated by measuring the transmittance in the visible light wavelength range of 380 to 780 nm using a spectrophotometer U-4100 (Hitachi High-Tech Science Corporation) and calculating the average visible light transmittance.

[0085] (Coatability) A light-shielding layer of approximately 20 μm thickness was screen-printed on a 100 mm square surface of each fiber sheet on which the light-shielding layer was to be printed using black ink and a screen plate (T-270), and the presence or absence of unevenness in the black ink coating was visually judged according to the following criteria. A: Uniformly coated B: Uncoated areas / uneven coating

[0086] (Light blocking property) A light source was applied to the printed surface of the screen-printed fiber sheet with a light-shielding layer, and the degree of light transmission when viewed from the opposite surface was visually judged according to the following criteria: The light source had a brightness of 40 lumens, was a circle with a diameter of 3.5 mm, and was 1.0 mm away from the sample. A: No light was transmitted at all. B: The light was transmitted enough that the outline of the light source was not visible. C: The light was transmitted enough that the outline of the light source could be seen.

[0087] [Example 1] Ethylene-modified polyvinyl alcohol as the thermoplastic resin for the sea part and isophthalic acid-modified polyethylene terephthalate with a Tg of 110°C as the thermoplastic resin for the island parts were melted separately. Then, each molten resin was supplied to a multiple spinneret having a large number of nozzle holes arranged in parallel so that a cross section in which 25 island parts with uniform cross-sectional areas were distributed in the sea part was formed. At this time, the supply was performed while adjusting the pressure so that the mass ratio of the sea part to the island parts was sea part / island part = 25 / 75. Then, the molten resin was discharged from the nozzle hole whose spinneret temperature was set to 260°C.

[0088] The molten resin discharged from the nozzle holes was drawn by sucking with an air jet nozzle type suction device in which the air flow pressure was adjusted so that the average spinning speed was 3700 m / min, and islands-in-sea type composite long fibers with an average fineness of 2.1 dtex were spun. The spun islands-in-sea type composite long fibers were continuously deposited on a movable net while being sucked from the back side of the net. To suppress fluffing on the surface, the islands-in-sea type composite long fibers deposited on the net were lightly pressed with a metal roll at 42°C. The islands-in-sea type composite long fibers were peeled off from the net and passed between a lattice-patterned metal roll and a back roll with a surface temperature of 75°C, whereby they were heat-pressed at a linear pressure of 200 N / mm. In this manner, a long-fiber web was obtained.

[0089] Next, an oil containing an antistatic agent was sprayed onto the surface of the obtained long fiber web, and then 10 long fiber webs were stacked using a cross-wrapper to form a laminated web, which was then sprayed with an oil to prevent needle breakage.The laminated web was then needle-punched to perform a three-dimensional entanglement process, thereby obtaining an entangled web.

[0090] The obtained entangled web was densified by wet heat shrinkage treatment as follows. Specifically, 10% by mass of water at 18°C ​​was uniformly sprayed onto the entangled web, and the web was left in an atmosphere of 70°C and 95% relative humidity for 3 minutes without tension to cause wet heat shrinkage and improve the apparent fiber density. The entangled web was then subjected to dry heat roll pressing to further densify it.

[0091] Next, the densified entangled web was impregnated with polyurethane as follows: Polycarbonate / ether-based polyurethane-based polyurethane emulsion (solid concentration 30%) was impregnated into the densified entangled web, and the water was dried in a drying oven at 150°C, and the non-foamed polyurethane was crosslinked.

[0092] The resulting composite of polyurethane and entangled web was immersed in hot water at 95° C. for 20 minutes to extract and remove the sea component contained in the islands-in-sea type composite long fibers, and then dried in a drying oven at 120° C. In this manner, a fiber sheet substrate having a thickness of about 1.50 mm was obtained.

[0093] Then, a fiber sheet substrate with a thickness of about 1.50 mm was sliced ​​in half. Then, the first surface of the fiber sheet substrate, which is located on the light-emitting surface side of the light-emitting member described later and is the surface on which the light-shielding layer is printed, was buffed with sandpaper of #120 so as to be flat. The conditions of the buffing treatment were set as follows: the rotation speed of the buff roller was 650±50 rpm, the rotation direction was the opposite direction to the moving direction of the fiber sheet, and the conveying speed of the substrate was 3 m / min. The treatment was performed twice so that the actual measured thickness was the target thickness of 0.36±0.03 mm. The buffing treatment of the second surface, which is not located on the light-emitting surface side of the light-emitting member and is the outer surface side of the light-emitting display device, was performed under the same conditions as the first surface, except that the sandpaper was changed to sandpaper of #240.

[0094] The fiber sheet was pressed by a manual press at room temperature and a surface pressure of 8.8 MPa to obtain a fiber sheet A.

[0095] The fiber sheet A has a thickness of 0.35 mm and an apparent density of 0.515 g / cm, and is made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of fiber sheet A on which the light-shielding layer was printed had an arithmetic mean height Sa of 8.8 μm based on ISO 25178, and the opposite surface was formed into a suede-like napped surface with an arithmetic mean height Sa of 13.4 μm.

[0096] The results are shown in the following Table 1. Fiber sheet A was a fiber sheet exhibiting good coatability and high light-shielding properties.

[0097] [Table 1]

[0098] [Example 2] Fiber sheet B was produced in the same manner as in Example 1, except that the pressing temperature was changed to 110°C instead of room temperature. Fiber sheet B had a thickness of 0.23 mm and an apparent density of 0.815 g / cm3, and was made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of Fiber Sheet B on which the light-shielding layer was printed had an arithmetic mean height Sa of 5.6 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 5.2 μm. The results are shown in Table 1. Fiber Sheet B was a fiber sheet that exhibited good coatability and high light-shielding properties.

[0099] [Example 3] Fiber sheet C was produced in the same manner as in Example 1, except that the pressing temperature was changed to 140°C instead of room temperature. Fiber sheet C had a thickness of 0.22 mm and an apparent density of 0.853 g / cm, and was made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of Fiber Sheet C on which the light-shielding layer was printed had an arithmetic mean height Sa of 4.2 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 4.1 μm. The results are shown in Table 1. Fiber Sheet C was a fiber sheet that exhibited good coatability and high light-shielding properties.

[0100] [Example 4] Fiber sheet D was produced in the same manner as in Example 1, except that after pressing, the printed surface was buffed with #120 sandpaper. Fiber sheet D was a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric, with a thickness of 0.36 mm and an apparent density of 0.535 g / cm. 3 The surface of Fiber Sheet D on which the light-shielding layer was printed had an arithmetic mean height Sa of 17.8 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 14.1 μm. The results are shown in Table 1. Fiber Sheet D was a fiber sheet that exhibited good coatability and high light-shielding properties.

[0101] [Example 5] A solution of a polycarbonate-based non-yellowing polyurethane resin was applied to the surface of the release paper and dried at 80°C for 10 minutes to form a polyurethane film with a thickness of 30 μm. A polycarbonate-based non-yellowing two-component curing polyurethane solution was then applied to the surface of the formed polyurethane film as an adhesive layer and dried at 50°C for 3 minutes to form an adhesive layer with a thickness of 70 μm. In this way, a flat resin layer with a thickness of 100 μm was formed.

[0102] Then, a grain-finished resin layer formed on a release paper was attached to the surface of the fiber sheet A obtained in Example 1 having an arithmetic mean height Sa of 13.4 μm, and heated at 80° C. for 2 minutes. In this manner, a fiber sheet E of grain-finished artificial leather having a resin layer and a thickness of 0.45 mm was prepared. The fiber sheet E is a nonwoven fabric impregnated with polyurethane and has an apparent density of 0.540 g / cm. 3 The arithmetic mean height Sa of the surface of Fiber Sheet E on which the light-shielding layer was printed was 9.1 μm, based on ISO 25178. The results are shown in Table 1. Fiber Sheet E was a fiber sheet that exhibited good coatability and high light-shielding properties.

[0103] [Comparative Example 1] A fiber sheet F was produced in the same manner as in Example 1, except that the pressing treatment was not performed. The fiber sheet F had a thickness of 0.41 mm and an apparent density of 0.452 g / cm3, and was made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of Fiber Sheet F on which the light-shielding layer was printed had an arithmetic mean height Sa of 8.6 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 12.4 μm. The results are shown in Table 1. Fiber Sheet F had good coatability with no coating unevenness, but slight light leakage was observed in the light-shielding layer when irradiated with light from the light source, indicating low light-shielding properties.

[0104] [Comparative Example 2] A fiber sheet G was produced in the same manner as in Example 1, except that the press treatment was not performed, and the first surface, which is the surface on which the light-shielding layer is printed, was buffed with #100 sandpaper instead of #120 sandpaper. The fiber sheet G had a thickness of 0.41 mm and an apparent density of 0.466 g / cm, and was made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of Fiber Sheet G on which the light-shielding layer was printed had an arithmetic mean height Sa of 21.7 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 12.7 μm. The results are shown in Table 1. Fiber Sheet G had uneven coating and poor coatability, and slight light leakage was confirmed in the light-shielding layer when irradiated with light from a light source, making it a fiber sheet with low light-shielding properties.

[0105] [Comparative Example 3] Fiber sheet H was produced in the same manner as in Example 1, except that the manufacturing conditions of the fiber sheet substrate were changed so that the nonwoven fabric contained ultrafine fibers with a fineness of 0.05 dtex and polyurethane was impregnated into the nonwoven fabric, no pressing was performed, and the first surface on which the light-shielding layer was to be printed was buffed with #100 sandpaper instead of #120 sandpaper. Fiber sheet H had a thickness of 0.41 mm and an apparent density of 0.582 g / cm. 3 The surface of Fiber Sheet H on which the light-shielding layer was printed had an arithmetic mean height Sa of 24.2 μm based on ISO 25178, and the opposite surface was formed with a suede-like napped surface with an arithmetic mean height Sa of 12.8 μm. The results are shown in Table 1. Fiber Sheet H had good light-shielding properties, but had uneven coating.

[0106] [Comparative Example 4] Apparent density is 0.429g / cm 3Fiber sheet I was prepared as a 0.57 mm thick grain-finished artificial leather having a polyurethane resin layer on the surface of a polyurethane-impregnated nonwoven fabric. The arithmetic mean height Sa of the surface of fiber sheet I on which the light-shielding layer was printed was 34.5 μm based on ISO 25178. The results are shown in Table 1. Fiber sheet I had uneven coating and, when irradiated with light from a light source, the boundary between the light-shielding layer and the light-transmitting portion was unclear, resulting in a fiber sheet with poor concealment properties.

[0107] [Comparative Example 5] Fiber sheet J was produced in the same manner as in Example 2, except that a step of applying a small amount of polyurethane to seal the first surface, which is the surface on which the light-shielding layer is printed after buffing, was added to smooth the first surface. Fiber sheet J had a thickness of 0.21 mm and an apparent density of 0.891 g / cm, and was made of a nonwoven fabric containing ultrafine fibers with a fineness of 0.08 dtex and polyurethane impregnated into the nonwoven fabric. 3 The surface of Fiber Sheet J on which the light-shielding layer was printed had an arithmetic mean height Sa of 2.5 μm based on ISO 25178, and the opposite surface had a suede-like napped layer formed with an arithmetic mean height Sa of 4.9 μm. The results are shown in Table 1. Fiber Sheet J had good light-shielding properties, but had uneven coating. [Explanation of symbols]

[0108] 1. Fiber sheet 2 Light blocking layer 3. Fiber sheet with light-shielding layer 4 Surface resin layer 5. Illuminating materials 5a Light emitting diode device (LED) 5b Circuit board 10 Light-emitting display device of the first embodiment 11 Fiber sheet 20 Light-emitting display device according to the second embodiment 30 Light-emitting display device according to the third embodiment 40 Light-emitting display device according to the fourth embodiment 50 Base material 100 Buffing processing device 111 Delivery roller 112 Winding roller 113 Pressure roller 114 Buffalo 115 Drive roller 116 Abrasive Belt D Transparent part E Emission

Claims

1. A light-emitting display device comprising: a light-emitting member; and a fiber sheet with a light-shielding layer that covers a light-emitting surface of the light-emitting member, The fiber sheet with a light-shielding layer includes a fiber sheet and a light-shielding layer partially printed on at least one surface of the fiber sheet, The surface of the fiber sheet on which the light-shielding layer is formed has an arithmetic mean height Sa based on ISO25178 of 3 to 20 μm, and the apparent density of the fiber sheet is 0.5 g / cm 3 This is the light-emitting display device.

2. The light-emitting display device according to claim 1 , wherein the light-shielding layer is printed on a first surface of the fiber sheet that is located on the side of the light-emitting surface.

3. 3. The light-emitting display device according to claim 1, wherein the light-shielding layer-attached fiber sheet has a napped surface on a second surface of the fiber sheet not located on the light-emitting surface side, the surface layer being treated to have napped fibers.

4. The light-emitting display device according to claim 1 , wherein the light-shielding layer is printed on a second surface of the fiber sheet that is not located on the side of the light-emitting surface.

5. 2. The light-emitting display device as described in claim 1, wherein the light-shielding layer is printed on both a first surface of the fiber sheet that is located on the side of the light-emitting surface and a second surface of the fiber sheet that is not located on the side of the light-emitting surface.

6. The light-emitting display device according to claim 1 , wherein the fiber sheet with a light-shielding layer further comprises a surface resin layer having optical transparency on a second surface of the fiber sheet that is not located on the light-emitting surface side.

7. 7. The light-emitting display device according to claim 1, wherein the fiber sheet comprises a nonwoven fabric of ultrafine fibers having a fineness of 1 dtex or less, and 3 to 40% by mass of a polymeric elastomer impregnated into the nonwoven fabric.

8. A light-emitting display device described in any one of claims 1 to 7, wherein the arithmetic mean value of the transmittance of the fiber sheet in the visible light wavelength range of 380 to 780 nm is 0.1% or more.

9. A fiber sheet with a light-shielding layer for use in a light-emitting display device that covers a light-emitting surface of a light-emitting member and selectively transmits light emitted from the light-emitting member to display a symbol, pattern, or image, The present invention includes a fiber sheet having a first surface located on the light-emitting surface side and a second surface located on the outer surface side, and a light-shielding layer partially printed on at least one of the first surface and the second surface, The surface of the fiber sheet on which the light-shielding layer is formed has an arithmetic mean height Sa based on ISO25178 of 3 to 20 μm and an apparent density of 0.5 g / cm 3 This is the fiber sheet with a light-shielding layer.

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