Protective sheet

The protective sheet enhances display unit design by allowing a pattern to be visible when the device is off, addressing the lack of appeal in conventional black screens.

JP2025145889APending Publication Date: 2025-10-03TOPPAN HOLDINGS INC
View PDF 1 Cites 0 Cited by

Patent Information

Application Number
JP2024046371
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-03-22
Publication Date
2025-10-03

AI Technical Summary

Technical Problem

Conventional protective sheets for image display devices appear black when not in use, lacking design appeal.

Method used

A protective sheet with a printed matter that transmits light when the display is on and conceals the display with a pattern when off, enhancing design even when the device is not displaying an image.

Benefits of technology

Improves the design of the display unit by allowing the user to see a pattern or image when the display is off, while still protecting the device.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 2025145889000001_ABST
    Figure 2025145889000001_ABST
Patent Text Reader

Abstract

To provide a protective sheet with which it is possible to improve the design quality of a display unit even when an image display device is not displaying images.SOLUTION: A protective sheet 100 protects a display unit 53 of an image display device 50 that displays images, and includes a printed matter 2. The printed matter 2 enables light from the image display device 50 to pass through when the image display device 50 is displaying the images. Therefore, when the images are displayed on the display unit 53, a user can visually recognize the images. On the other hand, the printed matter 2 hides the display unit 53 with a pattern of the printed matter 2 when the display unit 53 is turned off. Accordingly, the user can visually recognize a pattern of the printed matter 2, and not the display unit 53 when turned off.SELECTED DRAWING: Figure 18
Need to check novelty before this filing date? Find Prior Art

Description

[Technical Field]

[0001] The present invention relates to a protective sheet. [Background technology]

[0002] A conventional protective sheet for protecting the display unit of an image display device is disclosed in Patent Document 1. This protective sheet is attached to the display unit of a smartphone to protect the display unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-208138 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned protective sheet is a transparent sheet. Therefore, when the image display device is not displaying an image, the display unit shows a black screen without any image. There has been a demand for improving the design of the display unit even when the image display device is not displaying an image.

[0005] An object of the present invention is to provide a protective sheet that can improve the design of the display unit even when the image display device is not displaying an image. [Means for solving the problem]

[0006] [1] The protective sheet of the present invention is a protective sheet for protecting a display unit of an image display device that displays an image, and the protective sheet has a printed matter on which a picture is printed. The printed matter transmits light from the display unit when an image is displayed on the display unit, and conceals the display unit with the picture on the printed matter when the display unit is turned off.

[0007] The protective sheet protects the display unit of the image display device that displays an image, and also includes a printed matter. The printed matter transmits light from the image display device when the image is displayed on the image display device. Therefore, when an image is displayed on the display unit, the user can see the image. On the other hand, when the display unit is turned off, the printed matter conceals the display unit with a pattern on the printed matter. Therefore, the user can see the pattern on the printed matter, not the display unit when turned off. As a result, the design of the display unit can be improved even when the display unit is not displaying an image.

[0008] [2] In the protective sheet of [1] above, the image display device may be a touch panel type mobile terminal. In this case, the design of the display unit of the mobile terminal can be improved.

[0009] [3] In the protective sheet of [1] or [2] above, the image on the printed matter includes a picture of a predetermined character, and the printed matter displays the character picture as visual information when the display unit is turned off, and displays the image as visual information in place of the character picture when the display unit is displaying an image. In this case, the character picture can be seen on the display unit when the light is off, thereby improving the design. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a protective sheet that can improve the design of the display unit even when the image display device is not displaying an image. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a display device according to Example 1-1. [Figure 2] FIG. 2 is a cross-sectional view schematically showing a picture print layer included in the display device shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view schematically showing a printed matter according to Example 1-2. [Figure 4] FIG. 4 is a cross-sectional view schematically showing a white pattern layer included in the printed matter shown in FIG. [Figure 5] FIG. 5 is a cross-sectional view schematically showing a printed matter according to Example 1-3. [Figure 6] FIG. 6 is a cross-sectional view schematically showing a printed matter according to Example 1-4. [Figure 7] FIG. 7 is a cross-sectional view schematically showing a picture print layer included in a display device according to Example 2-1. [Figure 8] FIG. 8 is a table showing the configuration of printed matter according to Experimental Examples 1 to 3. [Figure 9] FIG. 9 is a cross-sectional view schematically showing a picture print layer included in a display device according to Example 3-1. [Figure 10] FIG. 10(a) is a schematic diagram showing the color combinations of the picture print layer, and FIG. 10(b) is a schematic diagram showing the color combinations of the picture print layer according to a comparative example. [Figure 11] FIG. 11 is a schematic diagram showing a specific example of a color combination of the picture print layer. [Figure 12] FIG. 12 is a cross-sectional view schematically showing a picture print layer included in a display device according to Example 4-1. [Figure 13] FIG. 13(a) is a schematic diagram showing the color combinations of the picture print layer, and FIG. 13(b) is a schematic diagram showing the color combinations of the picture print layer according to a comparative example. [Figure 14] FIG. 14 is a schematic diagram showing a specific example of a color combination of the picture print layer. [Figure 15] Figure 15(a) is a view of the light source covered with printed matter viewed from the front side when the power of the light source 3 is OFF, and Figure 15(b) is a view of the light source covered with printed matter viewed from the front side when the power of the light source 3 is ON. [Figure 16] FIG. 16 is a perspective view showing an image display device that employs a protective sheet according to this embodiment. [Figure 17] FIG. 17 is a perspective development view of the protection sheet and the image display device. [Figure 18] FIG. 18(a) is a diagram showing the state when the display unit is turned off, and FIG. 18(b) is a diagram showing the state when the display unit is lit. [Figure 19]FIG. 19 is a cross-sectional view of the protection sheet. [Figure 20] FIG. 20 is a diagram showing a protective sheet according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0012] [About printed materials] First, examples of printed materials used in this embodiment will be described with reference to FIGS. 1 to 15. However, the contents described with reference to FIGS. 1 to 15 are merely examples of printed materials that can be employed in the present invention. Therefore, the layer structures of printed materials exemplified in the description with reference to FIGS. 1 to 15 do not limit the layer structures of printed materials employed in the present invention. For the purpose of describing printed materials, FIG. 1 shows the printed material incorporated into a display device. In this specification, when a printed material is formed by printing dot-shaped ink, the layer structure of the printed material may include a structure in which a portion of one layer and a portion of another layer are located at the same position in the thickness direction or may intersect with each other. When viewed in a plan view, the layer structure may also include a structure in which a pattern forming one layer and a pattern forming another layer partially overlap and do not overlap in other portions. Note that each layer in the layer structure of the printed material can also be considered as a stack of printed patterns.

[0013] [Example 1-1] FIG. 1 is a cross-sectional view schematically showing a display device according to Example 1-1. FIG. 2 is a cross-sectional view schematically showing a picture-printed layer included in the display device shown in FIG. 1. As shown in FIG. 1, the display device 1 includes a printed material 2 and a light source 3. The printed material 2 is a sheet for expressing a picture, and includes a light-transmitting substrate 4, a picture-printed layer 5, and a transparent smoke-printed layer 30. The printed material 2 is provided in front of the light source 3 (between the viewer and the light source 3). The printed material 2 is fully light-transmitting. Therefore, when the light source 3 is powered on, the viewer can see the light from the light source 3 that has passed through the printed material 2, and when the light source 3 is powered off, the viewer can see the picture expressed by the printed material 2. The light source 3 is, for example, a display device.

[0014] The light-transmitting substrate 4 is a substrate that is transparent to visible light. The light-transmitting substrate 4 is made of, for example, a transparent resin. Examples of transparent resins include PET, PMMA, polycarbonate, polyethylene, polypropylene, and nylon. The light-transmitting substrate 4 may be a glass substrate. The thickness of the light-transmitting substrate 4 is, for example, 25 μm to 250 μm, but as long as printing is possible, a substrate having a thickness less than or greater than this range can also be used. In the case of a glass substrate, the thickness is, for example, about several mm to 10 mm. If necessary, a surface protection layer may be provided on the surface side of the light-transmitting substrate 4 (the side opposite to the picture-printed layer 5).

[0015] The picture-printed layer 5 is a layer that expresses the picture of the printed matter 2. The picture-printed layer 5 includes a first color pattern layer 10 provided on one surface 4a of the light-transmitting substrate 4, and a second color pattern layer 20 provided on the first color pattern layer 10.

[0016] The first color pattern layer 10 can be formed on the surface 4a by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 2, the first color pattern layer 10 is composed of a plurality of first color dots 11. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle but may be a rectangle, a polygon, or other shape. Each of the plurality of first color dots 11 contains a first color binder 12 and a plurality of first color pigment chips 13 dispersed within the first color binder 12. The content of the plurality of first color pigment chips 13 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the first color binder 12 is 100 parts by weight.

[0017] Examples of the first color binder 12 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, and polycarbonate resins. The thickness of the first color pattern layer 10 is, for example, 1 μm to 10 μm. The first color pattern layer 10 may contain a curing agent. In this case, the heat resistance of the first color pattern layer 10 and the adhesion of the first color pattern layer 10 to the light-transmitting substrate 4 can be improved. The first color pattern layer 10 may also contain a weathering agent. Known ultraviolet absorbers and light stabilizers can be used as the weathering agent.

[0018] In Example 1-1, the multiple first color pigment chips 13 are multiple color first interference pigments 14a, 14b that generate different interference light from each other. Each of the first interference pigments 14a, 14b is composed of a thin flake (not shown) that is transparent to visible light and a metal oxide film (not shown) that covers the flake. Light incident on the first color pattern layer 10 from the translucent substrate 4 side and reflected from the surface of the metal oxide film interferes with light that passes through the metal oxide film and is reflected from the surface of the flakes, generating interference light. Adjusting the film thickness and refractive index of the metal oxide film allows for generation of interference light with a desired wavelength.

[0019] In Example 1-1, each of the first interference pigments 14a and 14b is titanium dioxide-coated mica. The particle size range of the titanium dioxide-coated mica includes, for example, a range of 25 μm to 60 μm. Here, "particle size" refers to the longest diameter of the particle cross section. The flakes that make up the first interference pigments 14a and 14b may be made of materials other than mica, such as silica, alumina, glass, or polysilicate. The metal oxide films that make up the first interference pigments 14a and 14b may be made of materials other than titanium dioxide, such as zirconium oxide, zinc oxide, iron oxide, or tin oxide.

[0020] When incident light E enters the first color pattern layer 10, the first interference pigments 14a and 14b generate first interference light beams 15a and 15b, which are different from each other. That is, the wavelengths of the first interference light beams 15a and 15b are different from each other. As a result, the first interference pigments 14a and 14b exhibit a mixed color. The first interference pigments 14a and 14b are, for example, a red interference pigment (red pearl pigment) and a gold interference pigment (gold pearl pigment), respectively. In this case, the first interference light beams 15a and 15b exhibit red and gold, respectively. The blending amounts of the first interference pigments 14a and 14b may be the same or different from each other.

[0021] The second color pattern layer 20 can be formed on the first color pattern layer 10 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 2, the second color pattern layer 20 is composed of a plurality of second color dots 21. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle but may be a rectangle, a polygon, or other shape. Each of the plurality of second color dots 21 contains a second color binder 22 and a plurality of second color pigment chips 23 dispersed within the second color binder 22. The content of the plurality of second color pigment chips 23 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the second color binder 22 is 100 parts by weight.

[0022] Examples of the second color binder 22 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, and polycarbonate resins. The thickness of the second color pattern layer 20 is, for example, 1 μm to 10 μm. The second color pattern layer 20 may contain a curing agent. In this case, the heat resistance of the second color pattern layer 20 and the adhesion of the second color pattern layer 20 to the first color pattern layer 10 can be improved. The second color pattern layer 20 may also contain a weathering agent. Known ultraviolet absorbers and light stabilizers can be used as the weathering agent.

[0023] In Example 1-1, the multiple second color pigment chips 23 are second interference pigments 24 that generate monochromatic interference light different from the mixed color of the first interference pigments 14a and 14b. The second interference pigment 24 is composed of flakes (not shown) that are transparent to visible light and a metal oxide film (not shown) that covers the flakes. Light incident on the second color pattern layer 20 from the translucent substrate 4 side is reflected by the surface of the metal oxide film, and light that passes through the metal oxide film and is reflected by the surface of the flakes interferes with each other to generate interference light. Adjusting the film thickness and refractive index of the metal oxide film allows for the generation of interference light with a desired wavelength.

[0024] In Example 1-1, the second interference pigment 24 is titanium dioxide-coated mica. The particle size range of the titanium dioxide-coated mica includes, for example, a range of 25 μm to 60 μm. Here, "particle size" refers to the longest diameter of the particle cross section. The flakes that make up the second interference pigment 24 may be made of a material other than mica, such as silica, alumina, glass, or polysilicate. The metal oxide film that makes up the second interference pigment 24 may be made of a material other than titanium dioxide, such as zirconium oxide, zinc oxide, iron oxide, or tin oxide.

[0025] When incident light E enters the second color pattern layer 20, the second interference pigment 24 generates a monochromatic second interference light 25. As a result, the second interference pigment 24 exhibits a monochromatic color. The second interference pigment 24 may be any interference pigment that generates a monochromatic second interference light 25 different from the mixed color exhibited by the first interference pigments 14a and 14b, and may be, for example, a green interference pigment (green pearl pigment). In this case, the second interference light 25 exhibits green color.

[0026] The transparent smoke printed layer 30 has the function of attenuating light from the front side of the viewpoint that passes through the printed matter 2. The transparent smoke printed layer 30 is provided on the outermost surface of the picture printed layer 5, opposite the light-transmitting substrate 4. In Example 1-1, the transparent smoke printed layer 30 is provided on the second color pattern layer 20, as shown in FIG. 1. The transparent smoke printed layer 30 can be provided on the second color pattern layer 20 by, for example, screen printing, inkjet printing, gravure printing, or offset printing using an ink in which a small amount of carbon black is dispersed in a resin binder such as a vinyl, acrylic, urethane, or polyester binder. The thickness of the transparent smoke printed layer 30 is, for example, 1 μm to 10 μm. The transparent smoke printed layer 30 may contain a curing agent. In this case, the heat resistance of the transparent smoke printed layer 30 and the adhesion of the transparent smoke printed layer 30 to the second color pattern layer 20 can be improved. Furthermore, a weatherproofing agent may be contained in the transparent smoke printed layer 30. As the weatherproofing agent, known ultraviolet absorbers and light stabilizers can be used.

[0027] In the printed matter 2, the image is expressed by additively mixing the first interference light 15a, 15b generated by the first interference pigments 14a, 14b and the second interference light 25 generated by the second interference pigment 24.

[0028] The total light transmittance of the printed matter 2 is, for example, 30% to 70%. The total light transmittance here refers to a value measured using a spectrophotometer (for example, spectrophotometer UV-2100 manufactured by Shimadzu Corporation).

[0029] In the printed matter 2 according to Example 1-1 described above, the first color pattern layer 10 contains the first interference pigments 14a and 14b, and the second color pattern layer 20 contains the second interference pigment 24, making it possible to achieve a three-dimensional image even with a small number of printed layers. Furthermore, in the printed matter 2, the first color pattern layer 10 is the only pattern layer of the first color pattern layer 10 and the second color pattern layer 20 that contains an interference pigment that generates different interference light from each other, making it possible to simplify color matching and registration work during printing. Therefore, the printed matter 2 makes it possible to achieve a three-dimensional image even with a small number of printed layers, and also simplifies color matching and registration work during printing.

[0030] In Example 1-1, the printed matter 2 includes a transparent smoke print layer 30 provided on the second color pattern layer 20. This provides better color development between the first color pattern layer 10 and the second color pattern layer 20. Furthermore, because the transparent smoke print layer 30 is transparent, a decrease in the visibility of the image on the display device 1 is effectively suppressed.

[0031] In Example 1-1, each of the first interference pigments 14a, 14b and the second interference pigment 24 contains titanium dioxide-coated mica with a particle size of 25 μm or more and 60 μm or less. When titanium dioxide-coated mica with a particle size of 25 μm or more is contained, the transparency and color development of the picture-printed layer 5 can be improved. When titanium dioxide-coated mica with a particle size of 60 μm or less is contained, a decrease in the resolution and gradation of the picture-printed layer 5 can be suppressed.

[0032] In Example 1-1, the content of the multiple first color pigment chips 13 is within a range of 0.5 parts by weight or more and 20 parts by weight or less, when the first color binder 12 is taken as 100 parts by weight, and the content of the multiple second color pigment chips 23 is within a range of 0.5 parts by weight or more and 20 parts by weight or less, when the second color binder is taken as 100 parts by weight. Because the content of the multiple first color pigment chips 13 is within a range of 0.5 parts by weight or more, the pattern of the first color pattern layer 10 is well expressed. Because the content of the multiple first color pigment chips 13 is within a range of 20 parts by weight or less, deterioration in the coating properties and transparency of the first color pattern layer 10 can be suppressed. Similarly, since the content of the multiple second color pigment chips 23 is within the range of 0.5 parts by weight to 20 parts by weight when the second color binder 22 is 100 parts by weight, the pattern of the second color pattern layer 20 is well expressed while preventing a decrease in the coating properties and transparency of the second color pattern layer 20.

[0033] In Example 1-1, the total light transmittance of the printed matter 2 is 30% to 70%. If the total light transmittance is 30% or more, when the printed matter 2 is placed in front of a screen, the light from the image on the screen makes it difficult to see the picture printed layer 5, and the image is more clearly visible. If the total light transmittance is 70% or less, the picture in the picture printed layer 5 can be prevented from appearing dark even when the screen is black.

[0034] In Example 1-1, the display device 1 includes a printed matter 2 and a light source 3. With the display device 1, when the light source 3 is not lit, the pattern on the pattern printed layer 5 is visible, and when the light source 3 is lit, the transmitted light from the light source 3 (pattern display, video display, etc.) is visible.

[0035] In Example 1-1, the light source 3 may be a display device. In this case, when the display is not lit, the pattern on the pattern-printed layer 5 is visible, and when the display is lit, transmitted light from the display (pattern display, video display, etc.) is visible.

[0036] As described above, the multiple interference pigments 14a, 14b, and 24 may contain pearl pigments. That is, the picture-printed layer 5 may contain multiple interference pearl pigments (interference pigments 14a, 14b, and 24) that are different from one another. Therefore, the printed matter 2 is a printed matter 2 that includes a translucent substrate 4 and a picture-printed layer 5, and the picture-printed layer 5 may contain multiple interference pearl pigments. This allows the picture-printed layer 5 to achieve a three-dimensional appearance.

[0037] The picture-printed layer 5 may include a first color pattern layer 10 containing an interference pearl pigment and a second color pattern layer 20 containing an interference pearl pigment, thereby allowing the picture-printed layer 5 to have a more three-dimensional appearance.

[0038] Each of the first color pattern layer 10 and the second color pattern layer 20 may contain a plurality of interference pearl pigments, thereby enabling the picture printed layer 5 to have a more three-dimensional appearance. For example, the second color pattern layer 20 may contain other interference pearl pigments in addition to the interference pigment 24.

[0039] The particle diameters of the plurality of interference pearl pigments may be different from one another. By including interference pearl pigments of different particle diameters in this way, a decrease in the transparency of the picture-printed layer 5 is suppressed.

[0040] The particle diameter of the plurality of interference pearl pigments may be 25 μm or more and 60 μm or less. In this case, the color development of the pattern of the pattern-printed layer 5 can be improved. Furthermore, by suppressing an unnecessary decrease in the transparency of the pattern-printed layer 5, the visibility of the image on the display device can be improved when the display device is used.

[0041] The interference pearl pigment may contain titanium dioxide-coated mica. In this case, the wavelength of the interference light can be adjusted by adjusting the thickness of the titanium dioxide film. Furthermore, by increasing the smoothness of the mica surface, the brightness can be improved.

[0042] The effect of the picture-printed layer 5 containing a plurality of interference pearl pigments can be obtained not only in the first example, but also in the second to sixth examples described later.

[0043] [Example 1-2] Below, a printed matter 2A according to Example 1-2 will be described with reference to Figures 3 and 4. Note that in the description of Example 1-2, descriptions that overlap with Example 1-1 above will be omitted, and only differences from Example 1-1 above will be described. In other words, to the extent technically possible, descriptions from Example 1-1 above may be used appropriately in Example 1-2.

[0044] Fig. 3 is a cross-sectional view schematically showing a printed matter according to Example 1-2. Fig. 4 is a cross-sectional view schematically showing a white pattern layer provided in the printed matter shown in Fig. 3. The printed matter 2A includes a light-transmitting substrate 4 and a picture printed layer 5. The printed matter 2A further includes a white pattern layer 40 provided on the second color pattern layer 20.

[0045] The white pattern layer 40 can be formed on the second color pattern layer 20 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 4 , the white pattern layer 40 is composed of a plurality of silver dots 41. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle, but may be a rectangle, a polygon, or other shape. Each of the plurality of silver dots 41 contains a silver binder 42 and a plurality of silver pigment chips 43 dispersed within the silver binder 42. The content of the plurality of silver pigment chips 43 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the silver binder 42 is 100 parts by weight.

[0046] Examples of the silver binder 42 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, and polycarbonate resins. The thickness of the white pattern layer 40 is, for example, 1 μm to 10 μm. The white pattern layer 40 may contain a curing agent. In this case, the heat resistance of the white pattern layer 40 and the adhesion of the white pattern layer 40 to the second color pattern layer 20 can be improved. The white pattern layer 40 may also contain a weathering agent. Known ultraviolet absorbers and light stabilizers can be used as the weathering agent.

[0047] The configuration of the printed matter 2A described above also achieves the same effects as in Example 1-1 above. Furthermore, Example 1-2 includes a white pattern layer 40 formed on the second color pattern layer 20 and composed of a plurality of silver dots 41, each of which contains a silver binder 42 and a plurality of silver pigment chips 43 dispersed within the silver binder 42. This provides excellent color development for the first color pattern layer 10 and the second color pattern layer 20, and allows the picture printed layer 5 to have a pattern that gives a whitish impression.

[0048] [Example 1-3] Below, a printed matter 2B according to Example 1-3 will be described with reference to Figure 5. Note that in the description of Example 1-3, descriptions that overlap with Examples 1-1 and 1-2 above will be omitted, and only differences from Examples 1-1 and 1-2 above will be described. In other words, to the extent technically possible, descriptions from Examples 1-1 and 1-2 above may be used appropriately in Example 1-3.

[0049] 5 is a cross-sectional view schematically showing a printed matter according to Example 1-3. The printed matter 2B comprises a light-transmitting substrate 4 and a picture print layer 5. That is, the printed matter 2B does not comprise a translucent smoke print layer 30 or a white pattern layer 40. Even with the configuration of the printed matter 2B described above, the same effects as those of Example 1-1 can be achieved.

[0050] [Example 1-4] Below, a printed matter 2C according to Example 1-4 will be described with reference to Figure 6. Note that in the description of Example 1-4, descriptions that overlap with Examples 1-1, 1-2, and 1-3 above will be omitted, and only differences from Examples 1-1, 1-2, and 1-3 above will be described. In other words, to the extent technically possible, descriptions from Examples 1-1, 1-2, and 1-3 above may be used appropriately in Example 1-4.

[0051] 6 is a cross-sectional view schematically showing a printed matter according to Example 1-4. The printed matter 2C comprises a light-transmitting substrate 4, a picture print layer 5, a white pattern layer 40, and a transmissive smoke print layer 30. The white pattern layer 40 is provided on the second color pattern layer 20, and the transmissive smoke print layer 30 is provided on the white pattern layer 40. The configuration of the printed matter 2C described above also achieves the same effects as those of Examples 1-1, 1-2, and 1-3.

[0052] The display device and printed matter according to the present disclosure are not limited to the above-described examples, and various other modifications are possible. For example, the second color pattern layer may include first interference pigments of multiple colors that generate different first interference lights, and the first color pattern layer may include a second interference pigment that generates a single-color second interference light that is different from the mixed color exhibited by the multiple first interference pigments. Furthermore, while the above examples show that the first color pigment chips are first interference pigments of two colors, the first color pigment chips may be first interference pigments of three or more colors.

[0053] [Second example] [Example 2-1] The printed matter and display device according to this example may have the same configuration as that shown in Fig. 1. Therefore, in the printed matter and display device according to this example, the description of the same configuration as that of the printed matter and display device of Example 1-1 will be omitted. The printed matter and display device according to Example 2-1 adopt the layer configuration shown in Fig. 7 instead of the layer configuration shown in Fig. 2.

[0054] The first interference pigment 14a includes a plurality of first titanium dioxide-coated micas 18a of a small particle size grade having a particle size range of 5 μm to 25 μm and a second titanium dioxide-coated mica 18b of a large particle size grade having a particle size range of 25 μm to 40 μm. The first interference pigment 14b includes a plurality of first titanium dioxide-coated micas 16a of a small particle size grade having a particle size range of 5 μm to 25 μm and a plurality of second titanium dioxide-coated micas 16b of a large particle size grade having a particle size range of 25 μm to 40 μm. The first titanium dioxide-coated micas 18a, 16a have an average particle size (D50) of, for example, about 15 μm, and the second titanium dioxide-coated micas 18b, 16b have an average particle size (D50) of, for example, about 25 μm. As a result, the average particle size of the first titanium dioxide-coated mica 18a, 16a is smaller than the average particle size of the second titanium dioxide-coated mica 18b, 16b. The second titanium dioxide-coated mica 18b, 16b may have a particle size range of 25 μm to 60 μm. In this case, the average particle size (D50) of the second titanium dioxide-coated mica 18b, 16b is, for example, approximately 35 μm. As shown in FIG. 7, each of the multiple first titanium dioxide-coated mica 18a, 16a is arranged so as to fill the gaps between the multiple second titanium dioxide-coated mica 18b, 16b. Here, "particle size" refers to the longest diameter of the particle cross section.

[0055] When incident light L enters the first color pattern layer 10, the first interference pigments 14a and 14b generate first interference lights 17a and 17b, which are different from each other. That is, the wavelengths of the first interference lights 17a and 17b are different from each other. As a result, the first interference pigments 14a and 14b exhibit a mixed color. The first interference pigments 14a and 14b may be, for example, a red interference pigment (red pearl pigment) and a gold interference pigment (gold pearl pigment), respectively. In this case, the first interference lights 17a and 17b exhibit red and gold, respectively. The first interference pigments 14a and 14b may be interference pigments of other colors. The blending amounts of the first interference pigments 14a and 14b may be the same or different from each other.

[0056] The second color pattern layer 20 may be the same as that shown in the first example.

[0057] The second interference pigment 24 includes a plurality of first titanium dioxide-coated micas 25a of a small particle size grade including a particle size range of 5 μm to 25 μm and a second titanium dioxide-coated mica 25b of a large particle size grade including a particle size range of 25 μm to 40 μm. The first titanium dioxide-coated micas 25a have an average particle size (D50) of, for example, about 15 μm, and the second titanium dioxide-coated micas 25b have an average particle size (D50) of, for example, about 25 μm. Thus, the average particle size of the first titanium dioxide-coated micas 25a is smaller than the average particle size of the second titanium dioxide-coated micas 25b. The second titanium dioxide-coated micas 25b may have a particle size range of 25 μm to 60 μm. In this case, the average particle size (D50) of the second titanium dioxide-coated micas 25b is, for example, about 35 μm. The plurality of first titanium dioxide-coated mica particles 25a are arranged so as to fill the gaps between the plurality of second titanium dioxide-coated mica particles 25b. Here, the "particle size" means the longest diameter of the cross section of the particle.

[0058] When incident light L enters the second color pattern layer 20, the second interference pigment 24 generates a single-color second interference light 26. As a result, the second interference pigment 24 exhibits a single color. The second interference pigment 24 may be any interference pigment that generates a single-color second interference light 26 different from the mixed color exhibited by the first interference pigments 14a and 14b, and may be, for example, a green interference pigment (green pearl pigment). In this case, the second interference light 26 exhibits green. The second interference pigment 24 may be an interference pigment of a color other than green.

[0059] The transparent smoke printed layer 30 is a layer for attenuating light transmitted through the printed matter 2. The transparent smoke printed layer 30 is provided on the outermost surface of the picture printed layer 5, opposite the light-transmitting substrate 4. In Example 2-1, the transparent smoke printed layer 30 is provided on the second color pattern layer 20, as shown in FIG. 1. The transparent smoke printed layer 30 can be provided on the second color pattern layer 20 by, for example, screen printing, inkjet printing, gravure printing, or offset printing using an ink in which a small amount of carbon black is dispersed in a resin binder such as a vinyl, acrylic, urethane, or polyester binder. The thickness of the transparent smoke printed layer 30 is, for example, 1 μm to 10 μm. The transparent smoke printed layer 30 may contain a curing agent. In this case, the heat resistance of the transparent smoke printed layer 30 and the adhesion of the transparent smoke printed layer 30 to the second color pattern layer 20 can be improved. Furthermore, a weatherproofing agent may be contained in the transparent smoke printed layer 30. As the weatherproofing agent, known ultraviolet absorbers and light stabilizers can be used.

[0060] In the printed matter 2, the image is expressed by additively mixing the first interference light 17a, 17b generated by the first interference pigments 14a, 14b and the second interference light 26 generated by the second interference pigment 24.

[0061] The total light transmittance of the printed matter 2 is, for example, 30% to 70%. The total light transmittance here refers to a value measured using a spectrophotometer (for example, spectrophotometer UV-2100 manufactured by Shimadzu Corporation).

[0062] In the printed matter 2 according to Example 2-1 described above, in the first color pattern layer 10, each of the plurality of first titanium dioxide-coated micas 18a, 16a having a small particle size range of 5 μm to 25 μm is arranged to fill the gaps between the plurality of second titanium dioxide-coated micas 18b, 16b having a large particle size range of 25 μm to 40 μm. In the printed matter 2, in the second color pattern layer 20, each of the plurality of first titanium dioxide-coated micas 25a having a small particle size range of 5 μm to 25 μm is arranged to fill the gaps between the plurality of second titanium dioxide-coated micas 25b having a large particle size range of 25 μm to 40 μm. Therefore, the printed matter 2 can provide a pattern with excellent visibility and color development. Furthermore, in the printed matter 2, the first color pattern layer 10 contains large particle size grade second titanium dioxide-coated mica 18b, 16b, and the second color pattern layer 20 contains large particle size grade second titanium dioxide-coated mica 25b, thereby suppressing a decrease in the transparency of the picture printed layer 5. Therefore, according to the printed matter 2, a decrease in the visibility of the image on the display device is effectively suppressed when the power is on.

[0063] In Example 2-1, the large particle size grade second titanium dioxide-coated mica 18b, 16b, 25b may have a particle size range of 25 μm to 60 μm. In this case, the color development of the pattern is more excellent. Furthermore, by suppressing an unnecessary decrease in the transparency of the pattern-printed layer 5, the visibility of the image on the display device 1 can be improved when used in the display device.

[0064] In Example 2-1, the first interference pigments 14a, 14b, and the second interference pigment 24 are interference pigments containing titanium dioxide-coated mica. Therefore, by adjusting the thickness of the titanium dioxide film, the wavelength of the interference light can be adjusted. Furthermore, by increasing the smoothness of the mica surface, the perceived brightness can be improved.

[0065] In the second example, the configurations according to Examples 1-2 to 1-4 in the first example may also be adopted.

[0066] In the above examples, the first interference pigment and the second interference pigment each contained a plurality of first titanium dioxide-coated micas and a plurality of second titanium dioxide-coated micas. However, it is sufficient that at least one of the first interference pigment and the second interference pigment contains a plurality of first titanium dioxide-coated micas and a plurality of second titanium dioxide-coated micas. Furthermore, in the above examples, the first color pigment chips were first interference pigments of two colors. However, the first color pigment chips may be first interference pigments of three or more colors. Furthermore, first interference pigments of multiple colors may be mixed.

[0067] [Experimental Example] Here, experimental examples will be used to explain the tendency of the appearance of images and patterns on LCD monitors depending on the particle size of the titanium dioxide-coated mica contained in the pattern print layer. As shown in FIG. 8 and Experimental Examples 1 to 3 described below, printed matter was produced with the particle size of the titanium dioxide-coated mica adjusted. FIG. 8 is a diagram showing the configuration of the printed matter according to Experimental Examples 1 to 3. An LCD monitor was placed on the back side (transparent smoke printed layer side) of the printed matter according to Experimental Examples 1 to 3. The distance between the printed matter and the LCD monitor was 2 mm. The visibility (items 1 to 4 described below) of the LCD monitor when it was turned on and off was evaluated. Sensory evaluation was conducted by four people for items 1 to 4, and the average score was calculated.

[0068] <Experimental Example 1> A printed material was produced by sequentially providing a first-color pattern layer, a second-color pattern layer, a white pattern layer, and a transparent smoke print layer on a transparent PET substrate. In Experimental Example 1, the first-color pattern layer was formed by screen printing using an ink containing a first-color binder (urethane resin) and red and gold interference pigments dispersed within the first-color binder. The red and gold interference pigment contents were as follows, per 100 parts by weight of the first-color binder: 8 parts by weight of a red interference pigment having a particle size of 10 to 40 μm, 2 parts by weight of a red interference pigment having a particle size of 5 to 25 μm, 5 parts by weight of a gold interference pigment having a particle size of 10 to 60 μm, and 2 parts by weight of a gold interference pigment having a particle size of 5 to 25 μm.

[0069] In Experimental Example 1, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and a green interference pigment dispersed within the second color binder. The green interference pigment content was 4 parts by weight of a green interference pigment with a particle size of 10 to 40 μm and 1 part by weight of a green interference pigment with a particle size of 5 to 25 μm, relative to 100 parts by weight of the second color binder. The red interference pigment, gold interference pigment, and green interference pigment were all titanium dioxide-coated mica.

[0070] In Experimental Example 1, a white pattern layer was formed by screen printing using an ink containing a silver binder (urethane resin) and silver pigment chips dispersed within the silver binder. The silver pigment chip content was 1 part by weight of silver pigment chips with particle sizes of 5 to 25 μm per 100 parts by weight of the silver binder. Furthermore, a transparent smoke print layer was formed by screen printing using an ink containing a medium ink and a black ink in a ratio of 40:1.

[0071] <Experimental Example 2> A printed material was produced by sequentially depositing a first-color pattern layer, a second-color pattern layer, a white pattern layer, and a transparent smoke print layer on a transparent PET substrate. In Experimental Example 2, the first-color pattern layer was formed by screen printing using an ink containing a first-color binder (urethane resin) and red and gold interference pigments dispersed within the first-color binder. The red and gold interference pigment contents were as follows, per 100 parts by weight of the first-color binder: 8 parts by weight of a red interference pigment having a particle size of 10 to 40 μm, 2 parts by weight of a red interference pigment having a particle size of 5 to 25 μm, 5 parts by weight of a gold interference pigment having a particle size of 10 to 60 μm, and 2 parts by weight of a gold interference pigment having a particle size of 5 to 25 μm.

[0072] In Experimental Example 2, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and a green interference pigment dispersed within the second color binder. The content of the green interference pigment was 4 parts by weight, with a particle size of 10 to 40 μm, for every 100 parts by weight of the second color binder. The red interference pigment, gold interference pigment, and green interference pigment were all titanium dioxide-coated mica.

[0073] In Experimental Example 2, a white pattern layer was formed by screen printing using an ink containing a silver binder (urethane resin) and silver pigment chips dispersed within the silver binder. The silver pigment chip content was 1 part by weight of silver pigment chips with particle sizes of 5 to 25 μm per 100 parts by weight of the silver binder. Furthermore, a transparent smoke print layer was formed by screen printing using an ink containing a medium ink and a black ink in a ratio of 40:1.

[0074] <Experimental Example 3> A printed material was produced by sequentially depositing a first color pattern layer, a second color pattern layer, and a transparent smoke print layer on a transparent PET substrate. In Experimental Example 3, the first color pattern layer was formed by screen printing using an ink containing a first color binder (urethane resin) and a green interference pigment dispersed within the first color binder. The green interference pigment content was 4 parts by weight of a green interference pigment having a particle size of 10 to 40 μm and 1 part by weight of a green interference pigment having a particle size of 5 to 25 μm, relative to 100 parts by weight of the first color binder.

[0075] In Experimental Example 3, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and red and gold interference pigments dispersed within the second color binder. The red and gold interference pigment contents were 8 parts by weight of red interference pigment with a particle size of 10 to 40 μm and 5 parts by weight of gold interference pigment with a particle size of 10 to 60 μm, relative to 100 parts by weight of the second color binder.

[0076] In Experimental Example 3, a transparent smoke print layer was formed by screen printing using a mixture of medium ink and black ink in a ratio of 40:1.

[0077] <Item 1: Clarity of displayed content> When the power of the LCD monitor was turned on, the clarity of the images and characters displayed on the LCD monitor was evaluated. <Score> 5 points: The image has little presence compared to the image and text displayed on the LCD monitor, and the image and text appear clear. 3 points: The image is somewhat strong compared to the image and text displayed on the LCD monitor, and the image appears to overlap the image and text slightly. 1 point: The image has a strong presence compared to the image and text displayed on the LCD monitor, and the image appears to overlap the image and text.

[0078] <Item 2: Brightness of the displayed content> When the power of the LCD monitor was turned on, the brightness of the images and characters displayed on the LCD monitor was evaluated. <Score> 5 points: Images and text displayed on the LCD monitor appear bright. 3 points: Images and text displayed on the LCD monitor appear slightly dark. 1 point: The image and text displayed on the LCD monitor appear quite dark.

[0079] <Item 3: Effects of black LCD monitors> The influence of the black LCD monitor on the image was evaluated when the LCD monitor was turned off. <Score> 5 points: There is no effect from the black color of the LCD monitor, and the image is clearly visible. 3 points: The black color of the LCD monitor is slightly noticeable, making the image appear slightly dark and muted (slightly high transparency). 1 point: The influence of the black color of the LCD monitor is evident, making the image appear quite dark and sunken (high transparency).

[0080] <Item 4: Color development of the pattern> The color development of the image was evaluated when the power of the LCD monitor was turned off. <Score> 5 points: The color of the pattern is good. 3 points: The color of the pattern is slightly weak and the color of the pattern appears pale (whitish). 1 point: The color of the pattern is weak and the color of the pattern appears white.

[0081] The results of the sensory evaluation of items 1 to 4 for Experimental Examples 1 to 3 are shown in Table 1 below. Any evaluation of 3 points or higher was deemed acceptable for practical use. Experimental Example 1 showed that the influence of the black LCD monitor on the image was fairly low, and the image visibility tended to be displayed at a sufficiently high level. High evaluation results were also obtained for the color development of the image and the clarity and brightness of the image and text display. Meanwhile, Experimental Examples 2 and 3 showed that the influence of the black LCD monitor on the image was kept low, while the color development of the image and the clarity and brightness of the image and text display tended to be generally good.

[0082] [Table 1]

[0083] [Third example] [Example 3-1] The printed matter and display device according to this example may have the same configuration as that shown in Fig. 1. Therefore, in the printed matter and display device according to this example, the description of the same configuration as that of the printed matter and display device of Example 1-1 will be omitted. The printed matter and display device according to this example employ the layer configuration shown in Fig. 9 instead of the layer configuration shown in Fig. 2.

[0084] The first color pattern layer 10 can be formed on the surface 4a by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 9 , the first color pattern layer 10 is composed of a plurality of first color dots 11. Here, "dot" refers to a point that constitutes a printed image. The shape of the dot is not limited to a circle, and it can be a rectangle, a polygon, or other shape. Each of the plurality of first color dots 11 contains a first color binder 12 and a plurality of first color pigment chips 13 dispersed within the first color binder 12. The content of the plurality of first color pigment chips 13 is, for example, in the range of 0.5 to 20 parts by weight, assuming the first color binder 12 is 100 parts by weight. In this case, the image of the first color pattern layer 10 is well expressed, while the deterioration of the coating property and transparency of the first color pattern layer 10 can be suppressed.

[0085] In Example 3-1, the multiple first color pigment chips 13 are interference pigments 14 (first interference pigments) that generate monochromatic interference light of a predetermined color. The interference pigments 14 are composed of flakes (not shown) that are transparent to visible light and a metal oxide film (not shown) that covers the flakes. Light incident on the first color pattern layer 10 from the translucent substrate 4 side that is reflected on the surface of the metal oxide film interferes with light that passes through the metal oxide film and is reflected on the surface of the flakes, generating interference light. Adjusting the film thickness and refractive index of the metal oxide film allows for the generation of interference light having a desired wavelength.

[0086] When incident light E is incident on the first color pattern layer 10, monochromatic interference light 15 (first interference light) is generated from the interference pigment 14. As a result, the interference pigment 14 exhibits a monochromatic color.

[0087] The second color pattern layer 20 can be formed on the first color pattern layer 10 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 9 , the second color pattern layer 20 is composed of a plurality of second color dots 21. Here, "dot" refers to a point that constitutes a printed image. The shape of the dot is not limited to a circle, and it may be rectangular, polygonal, or other shapes. Each of the plurality of second color dots 21 contains a second color binder 22 and a plurality of second color pigment chips 23 dispersed within the second color binder 22. The content of the plurality of second color pigment chips 23 is, for example, in the range of 0.5 to 20 parts by weight, assuming the second color binder 22 is 100 parts by weight. This allows the image of the second color pattern layer 20 to be well expressed while preventing a decrease in the coating properties and transparency of the second color pattern layer 20.

[0088] When incident light E is incident on the second color pattern layer 20, the interference pigment 24 (second interference pigment) generates monochromatic interference light 25 (second interference light). As a result, the interference pigment 24 exhibits a monochromatic color. The interference pigment 24 may be any interference pigment that generates monochromatic interference light 25 that is different from the color exhibited by the interference pigment 14.

[0089] The total light transmittance of the printed matter 2 is, for example, 30% to 70%. The total light transmittance here refers to the value measured using a spectrophotometer (for example, a UV-2100 spectrophotometer manufactured by Shimadzu Corporation). If the total light transmittance is 30% or more, when the printed matter 2 is placed in front of a screen, the light from the image on the screen makes it difficult to see the picture printed layer 5, and the image is more clearly visible. If the total light transmittance is 70% or less, the image in the picture printed layer 5 does not appear too dark even when the screen is black.

[0090] Next, the color combinations in the picture-printed layer 5 will be described with reference to Fig. 10 and Fig. 11. Fig. 10(a) is a schematic diagram showing the color combinations of the picture-printed layer 5. Fig. 10(b) is a schematic diagram showing the color combinations of the picture-printed layer 105 according to a comparative example. Fig. 11 is a schematic diagram showing specific examples of color combinations of the picture-printed layer 5.

[0091] As shown in FIG. 10(a), the first color pattern layer 10 contains an interference pigment of a single color "color A," thereby generating interference light of the single color "color A." The second color pattern layer 20 contains an interference pigment of a single color "color B," thereby generating interference light of the single color "color B." Color B is a different color from color A. Therefore, in the printed matter 2, the pattern is expressed by additively mixing the interference light of color A and the interference light of color B.

[0092] In the example shown in FIG. 11(a), "gold" is used as color A of the first color pattern layer 10, and "red" is used as color B of the second color pattern layer 20. The printed matter 2 may express a wood grain pattern as a design by additively mixing gold and red. The gold color of the first color pattern layer 10 can express a light wood grain. In this case, the interference pigment 14 shown in FIG. 9 is, for example, a gold interference pigment (gold pearl pigment). The interference light 15 represents gold. The interference pigment 24 is, for example, a red interference pigment (red pearl pigment). The interference light 25 represents red.

[0093] In the example shown in FIG. 11(b), "red" is used as color A of the first color pattern layer 10, and "gold" is used as color B of the second color pattern layer 20. The printed matter 2 may express a wood grain pattern as a design by additively mixing red and gold. By using red for the first color pattern layer 10, it is possible to express a wood grain pattern with a slightly reddish hue.

[0094] In the example shown in FIG. 11(c), "silver" is used as color A of the first color pattern layer 10, and "gold" is used as color B of the second color pattern layer 20. The printed matter 2 may express a hairline pattern as a design by additively mixing silver and gold. By making the second color pattern layer 20 gold, the usual stainless steel hairline can be adjusted to a gold tone. The interference pigment 14 shown in FIG. 9 is, for example, a silver interference pigment (silver pearl pigment). The interference light 15 indicates silver.

[0095] In the example shown in FIG. 11(d), "silver" is used as color A of the first color pattern layer 10, and "red" is used as color B of the second color pattern layer 20. The printed matter 2 may express a hairline pattern as a design by additively mixing silver and red. By using red for the second color pattern layer 20, the stainless steel hairline can be adjusted to a bronze tone.

[0096] In the example shown in FIG. 11(e), "gold" is used as color A of the first color pattern layer 10, and "silver" is used as color B of the second color pattern layer 20. The printed matter 2 may express a hairline pattern as a design by additively mixing gold and silver. By making the first color pattern layer 10 gold (or a color containing gold), a finish that further emphasizes the gold tone can be achieved.

[0097] In the printed matter 2 according to Example 3-1 described above, the first color pattern layer 10 contains an interference pigment 14 that generates a monochromatic interference light 15, and the second color pattern layer 20 contains an interference pigment 24 that generates a monochromatic interference light 25 that is different in color from the interference pigment 14. Here, as a comparative example, a printed matter 102 is shown in FIG. 10(b), in which the first color pattern layer 10 contains interference pigments of color X and color Y, and the second color pattern layer 20 contains an interference pigment of color Z. For example, to express a pattern such as that described in FIG. 11 using the configuration of the comparative example, it is necessary to adjust the three colors X, Y, and Z, which requires time-consuming color matching and registration during printing. On the other hand, for a pattern that can be expressed with a small number of colors, as in the printed matter 2 according to this example, by limiting the interference pigments contained in the first color pattern layer 10 and the second color pattern layer 20 to a single color, the pattern can be expressed using only the intensity of the single color. In this way, color matching and registration during printing can be simplified. Therefore, this printed matter 2 can simplify color matching and registration work during printing.

[0098] In the third example, the configurations according to Examples 1-2 to 1-4 in the first example may also be adopted.

[0099] [Example 4] [Example 4-1] The printed matter and display device according to this example may have the same configuration as that shown in Fig. 1. Therefore, in the printed matter and display device according to this example, the description of the same configuration as that of the printed matter and display device of Example 1-1 will be omitted. The printed matter and display device according to this example employ the layer configuration shown in Fig. 12 instead of the layer configuration shown in Fig. 2.

[0100] The first color pattern layer 10 can be formed on the surface 4a by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 12, the first color pattern layer 10 is composed of a plurality of first color dots 11. Here, "dot" refers to a point that constitutes a printed image. The shape of the dot is not limited to a circle, and it can be a rectangle, a polygon, or other shape. Each of the plurality of first color dots 11 contains a first color binder 12 and a plurality of first color pigment chips 13 dispersed within the first color binder 12. The content of the plurality of first color pigment chips 13 is, for example, in the range of 0.5 to 20 parts by weight, assuming the first color binder 12 is 100 parts by weight. In this case, the image of the first color pattern layer 10 is well expressed, while the coating property and transparency of the first color pattern layer 10 are prevented from being deteriorated.

[0101] In Example 4-1, the multiple first color pigment chips 13 are interference pigments 14 (second interference pigments) that generate monochromatic interference light of a predetermined color. The interference pigments 14 are the same color as one of the interference pigments 24a and 24b (first interference pigments) described below. The interference pigments 14 are composed of flakes (not shown) that are transparent to visible light and a metal oxide film (not shown) that covers the flakes. Light incident on the first color pattern layer 10 from the translucent substrate 4 side is reflected by the surface of the metal oxide film, and light that passes through the metal oxide film and is reflected by the surface of the flakes interferes with each other to generate interference light. Adjusting the film thickness and refractive index of the metal oxide film allows for the generation of interference light with a desired wavelength.

[0102] When incident light E is incident on the first color pattern layer 10, monochromatic interference light 15 (second interference light) is generated from the interference pigment 14. As a result, the interference pigment 14 exhibits a monochromatic color.

[0103] The second color pattern layer 20 can be formed on the first color pattern layer 10 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 12 , the second color pattern layer 20 is composed of a plurality of second color dots 21. Here, the term "dot" refers to a point that constitutes a printed image. The shape of the dot is not limited to a circle, and it may be rectangular, polygonal, or other shapes. Each of the second color dots 21 contains a second color binder 22 and a plurality of second color pigment chips 23 dispersed within the second color binder 22. The content of the second color pigment chips 23 is, for example, in the range of 0.5 to 20 parts by weight, assuming the second color binder 22 is 100 parts by weight. This allows the image of the second color pattern layer 20 to be well-expressed while preventing a decrease in the coating properties and transparency of the second color pattern layer 20.

[0104] In Example 4-1, the multiple second color pigment chips 23 are interference pigments 24a, 24b of multiple colors that generate different interference light from each other. Each of the interference pigments 24a, 24b is composed of a thin flake (not shown) that is transparent to visible light and a metal oxide film (not shown) that covers the thin flake. Light incident on the second color pattern layer 20 from the translucent substrate 4 side that is reflected on the surface of the metal oxide film interferes with light that passes through the metal oxide film and is reflected on the surface of the flake, generating interference light. Adjusting the film thickness and refractive index of the metal oxide film allows generation of interference light with a desired wavelength.

[0105] In Example 4-1, the interference pigments 24a and 24b are titanium dioxide-coated mica. The particle size range of the titanium dioxide-coated mica includes, for example, a range of 25 μm to 60 μm. Here, "particle size" refers to the longest diameter of the particle cross section. The flakes that make up the interference pigments 24a and 24b may be made of materials other than mica, such as silica, alumina, glass, or polysilicate. The metal oxide films that make up the interference pigments 24a and 24b may be made of materials other than titanium dioxide, such as zirconium oxide, zinc oxide, iron oxide, or tin oxide.

[0106] When incident light E enters the second color pattern layer 20, the interference pigments 24a, 24b generate different interference lights 125a, 125b (first interference lights), respectively. That is, the wavelengths of the interference lights 125a, 125b are different from each other. As a result, the interference pigments 24a, 24b exhibit a mixed color. The blending amounts of the interference pigments 24a, 24b may be the same or different from each other. The interference pigment 24a may be an interference pigment that generates interference light 125a of the same single color as the single color exhibited by the interference pigment 14. Note that the interference pigment 24b may be an interference pigment that generates interference light 126b of the same single color as the single color exhibited by the interference pigment 14.

[0107] The total light transmittance of the printed matter 2 is, for example, 30% to 70%. The total light transmittance here refers to the value measured using a spectrophotometer (for example, a UV-2100 spectrophotometer manufactured by Shimadzu Corporation). If the total light transmittance is 30% or more, when the printed matter 2 is placed in front of a screen, the light from the image on the screen makes it difficult to see the picture printed layer 5, and the image is more clearly visible. If the total light transmittance is 70% or less, the image in the picture printed layer 5 does not appear too dark even when the screen is black.

[0108] Next, the color combinations in the picture-printed layer 5 will be described with reference to Fig. 13 and Fig. 14. Fig. 13(a) and (b) are schematic diagrams showing the color combinations of the picture-printed layer 5. Fig. 13(c) is a schematic diagram showing the color combinations of the picture-printed layer 105 according to a comparative example. Fig. 14 is a schematic diagram showing specific examples of color combinations of the picture-printed layer 5.

[0109] As shown in FIG. 13(a), the first color pattern layer 10 contains an interference pigment of a single color "color A," thereby generating interference light of the single color "color A." The second color pattern layer 20 contains interference pigments of a single color "color A" and a single color "color B," thereby generating interference light of a mixture of "color A" and "color B." Color B is a different color from color A. Therefore, in the printed matter 2, the pattern is expressed by additively mixing the interference light of color A and the interference light of colors A and B.

[0110] Alternatively, as shown in FIG. 13(b), the second color pattern layer 20 contains an interference pigment of a single color "color A," thereby generating interference light of the single color "color A." The first color pattern layer 10 contains interference pigments of a single color "color A" and a single color "color B," thereby generating interference light of a mixture of "color A" and "color B." Color B is a different color from color A. Therefore, in the printed matter 2, the pattern is expressed by additively mixing the interference light of color A and the interference light of colors A and B.

[0111] In the example shown in FIG. 14(a), "gold" is used as color A of the first color pattern layer 10, and "gold" and "red" are used as color A and color B of the second color pattern layer 20, respectively. The printed matter 2 may express a wood grain pattern as a design by additively mixing gold and red. The gold color of the first color pattern layer 10 can express a light wood grain. In this case, the interference pigment 14 and interference pigment 24a shown in FIG. 12 are, for example, gold interference pigments (gold pearl pigments). The interference light 15 and interference light 125a represent gold. The interference pigment 24b is, for example, a red interference pigment (red pearl pigment). The interference light 126b represents red.

[0112] In the example shown in FIG. 14(b), "red" is used as color A of the first color pattern layer 10, and "red" and "gold" are used as color A and color B of the second color pattern layer 20. The printed matter 2 may express a wood grain pattern as a design by additively mixing red and gold. By using red for the first color pattern layer 10, it is possible to express a wood grain pattern with a slightly reddish tint.

[0113] In the example shown in FIG. 14(c), "silver" is used as color A of the first color pattern layer 10, and "silver" and "gold" are used as color A and color B of the second color pattern layer 20, respectively. The printed matter 2 may express a hairline pattern as a design by additively mixing silver and gold. By including gold in the second color pattern layer 20, the usual stainless steel hairline can be adjusted to a gold tone. The interference pigment 14 and interference pigment 24a shown in FIG. 12 are, for example, silver interference pigments (silver pearl pigments). The interference light 15 and interference light 126a indicate silver.

[0114] In the example shown in FIG. 14(d), "silver" is used as color A of the first color pattern layer 10, and "silver" and "red" are used as color A and color B of the second color pattern layer 20. The printed matter 2 may express a hairline pattern as a design by additively mixing silver and red. By including red in the second color pattern layer 20, the stainless steel hairline can be adjusted to a bronze tone.

[0115] In the example shown in FIG. 14(e), "silver" is used as color A and "gold" as color B of the first color pattern layer 10, and "silver" is used as color A of the second color pattern layer 20. The printed matter 2 may express a hairline pattern as a design by additively mixing gold and silver. By including gold (or a color containing gold) in the first color pattern layer 10, a finish that further emphasizes the gold tone can be achieved.

[0116] In the printed matter 2 according to Example 4-1 described above, either the first color pattern layer 10 or the second color pattern layer 20 contains interference pigments of multiple colors that generate interference light of different colors A and B, thereby achieving a three-dimensional image even with a small number of printed layers. Furthermore, in this printed matter 2, only one of the first color pattern layer 10 or the second color pattern layer 20 needs to contain the interference pigment that generates multiple interference light, thereby simplifying color matching and registration during printing. Meanwhile, the other of the first color pattern layer 10 or the second color pattern layer 20 contains an interference pigment that generates interference light of a single color, color A, that is the same as one of the multiple interference pigments. Here, as a comparative example, a printed matter 102 is shown in FIG. 13(c), in which the first color pattern layer 10 contains interference pigments of colors X and Y and the second color pattern layer 20 contains an interference pigment of color Z. For example, when creating a pattern like the one shown in Figure 14 using the comparative example configuration, it is necessary to adjust three colors, X, Y, and Z, which requires a lot of work for color matching and registration during printing. On the other hand, for patterns that can be created with a limited number of colors, such as those shown in Figure 14, the interference pigments in the first color pattern layer 10 and the second color pattern layer 20 can be limited to the same single color A, allowing the pattern to be created by varying the intensity of the single color A. Furthermore, when it is desired to emphasize the color A, using two layers, the first color pattern layer 10 and the second color pattern layer 20, makes it easier to adjust the color than adjusting it using only one color pattern layer. Furthermore, while adding too much interference pigment to one color pattern layer reduces the strength of the coating film, using two color pattern layers 10 and 20 can minimize this decrease in strength. As a result, color matching and registration during printing can be simplified.

[0117] In the fourth example, the configurations according to Examples 1-2 to 1-4 in the first example may also be adopted.

[0118] The printed matter and the display device are not limited to the above-described examples, and various other modifications are possible.

[0119] The printed matter may be a sheet in which a pattern layer and a concealing layer are laminated. The concealing layer is a layer that conceals the color of the display device when an image is not displayed, while transmitting the image when an image is displayed. The concealing layer is set to a predetermined range of visible light transmittance. An opening is formed in the concealing layer. The concealing layer may be printed using an inkjet device, for example, with a white ink containing titanium oxide. Specifically, the concealing layer may be printed, for example, in solid white, on the back of the pattern layer. An example of a printing method is an inkjet device, but is not limited to this. In addition to inkjet printing, various printing methods such as gravure printing, offset printing, letterpress printing, flexographic printing, screen printing, and electrostatic printing may be used to form the concealing layer. The printing method is not limited to the above-mentioned printing methods, and any conventionally known image forming method can be used, such as hand-drawing, ink-flowing, transfer printing, photography, electrophotography, photosensitive resin printing, vacuum deposition, chemical etching, thermal coloring, and discharge breakdown printing. The design layer is formed on the surface of the concealing layer using a printing method and is provided for the purpose of imparting design to the printed matter. The design layer may be applied to the entire surface as long as it has a certain degree of light transparency. Unlike the concealing layer, the design layer does not require the provision of openings, allowing for highly precise designs. Specifically, the design layer can be printed using an inkjet device, and the desired pattern may be printed using four colors of printing ink, for example, cyan, magenta, yellow, and black. Although an inkjet device has been exemplified as a method for printing the design layer, this is not limited thereto, and various printing methods can be applied, as with the concealing layer. The printed matter can adopt any known structure as long as it can exhibit the above-mentioned functions.

[0120] The concealment and visibility of the printed material 2 will be described in more detail with reference to FIG. 15 . Note that the description based on FIG. 15 is merely an example of a usage mode used to explain the properties of the printed material 2. Therefore, the present invention is not limited to this usage mode. FIGS. 15(a) and 15(b) are views of the front side of a light source 3 covered by the printed material 2. FIG. 15(a) shows the state when the light source 3 is turned off. FIG. 15(b) shows the state when the light source 3 is turned on. A wood grain pattern is used as the design of the printed material 2. A display device is used as the light source 3. The area of ​​the printed material 2 that covers the light source 3 is referred to as the display area DE. As shown in FIG. 15(a), when the light source 3 is turned off, the light source 3 is concealed by the design of the printed material 2. The printed material 2 conceals the light source 3 not with a light-blocking layer that blocks light, but with the light-transmitting design layer itself. Therefore, the visual information V1 displayed in the display area DE is the image of the printed matter 2. At this time, the viewer cannot see the display surface (black screen) of the light source 3 or the outline of the light source 3 from outside the printed matter 2. The visual information V1 visible in the display area DE and the visual information V2 visible in the area surrounding the display area DE are the same image of the printed matter 2. Therefore, the viewer cannot see the existence of the light source 3 from outside the printed matter 2.

[0121] As shown in FIG. 15(b), when the power supply of the light source 3 is ON, the light source 3 emits light and projects an arbitrary image GF onto the display surface. Here, the letter "X" printed on a monochrome background is used as the image GF. In the display area DE, the light of the image GF passes through the printed material 2. As a result, the viewer views the image GF by visually recognizing the transmitted light in the display area DE. Therefore, the visual information V3 displayed in the display area DE is the image GF projected by the light source 3. The content of the visual information V3 may include information not included in the content of the visual information V1. In this case, the visual information V3 may be composed only of light that has passed through the image of the printed material 2.

[0122] For example, as a comparative example, a sheet that displays the visual information "X" using a light source may be provided in which a portion of a light-shielding layer is cut out in the shape of an "X" to form a light-transmitting layer (different from the printed matter 2 of the present embodiment). Visual information V3 obtained using such a sheet and a light source such as a lamp has a background portion formed from a pattern on the surface of the light-shielding layer, and the "X" portion is formed from light from the light source that has passed through the light-transmitting layer. Another comparative example is a sheet in which a light-shielding layer in the shape of an "X" is formed on a portion of the light-transmitting layer. Visual information V3 obtained using such a sheet has a background portion formed from light from the light source that has passed through the light-transmitting layer, and the "X" portion is formed from a pattern on the surface of the light-shielding layer. In the comparative example, visual information V3 is provided by a combination of light that has passed through the sheet and light reflected from the surface of the sheet in the areas where the light is blocked. Furthermore, when a sheet such as the comparative example is used, the "X" shape is formed on the sheet itself in a manner that allows it to be seen even when the light source is turned off, so the visual information V1 also contains the content of "X." Therefore, the content of visual information V3 is already included in visual information V1.

[0123] Unlike a sheet using a light-shielding layer as in the comparative example, the visual information V3 in Fig. 15(b) using the printed matter 2 is entirely composed of light transmitted through the printed matter 2. Note that the entire printed matter 2 shown in Fig. 15 may be composed of a layer forming a light-transmitting pattern, or at least the entire display area DE may be composed of a layer forming a light-transmitting pattern. However, the printed matter 2 may also have a light-shielding layer provided in part of the display area DE, or a light-shielding layer provided in part of an area other than the display area DE.

[0124] Some display devices form a pattern in anticipation of the content of the image from the light source 3, and when the light source 3 is turned on, form visual information V3 by combining the pattern and the image. In the example shown in FIG. 15, the purpose is to make the presence of the light source 3 invisible from the outside, so the visual information V3 in FIG. 15(b) differs from the visual information V3 formed by such a combination. However, depending on the brightness of the image and the color of a certain area, it is acceptable for a faint pattern to be reflected in all or part of the visual information V3. Furthermore, for purposes different from those shown in FIG. 15, a combination of the pattern and the image of the printed material 2 may be used as visual information V3. If a touch panel is used as the light source 3, the user operates the touch panel via the printed material 2. Therefore, the printed material 2 may be set to a thickness, material, and hardness that do not interfere with touch panel operation.

[0125] FIG. 16 is a perspective view showing an image display device 50 employing the protective sheet 100 according to this embodiment. FIG. 17 is a perspective view showing the protective sheet 100 and the image display device 50 in an exploded view. The protective sheet 100 protects the display unit of the image display device 50, which displays images. Examples of the image display device 50 employing the protective sheet 100 include touch panel display devices and display devices without touch panel functionality. The image display device 50 may be a portable terminal or a built-in device. Examples of touch panel display devices include smartphones, tablet terminals, and PCs. Examples of display devices without touch panel functionality include televisions, PCs, and displays. In the example shown in FIG. 16, a smartphone, which is a touch panel portable terminal, is employed as the image display device 50. As shown in FIGS. 16 and 17, the image display device 50 as a smartphone includes a main body 52 and a display unit 53. The main body 52 includes electronic components and a rectangular, flat-plate-shaped housing that houses the electronic components. The display unit 53 is a touch panel type display device that is provided on substantially the entire main surface of the image display device 50 and displays images.

[0126] The printed material 2 may be one of the examples exemplified above. A picture is printed on the printed material 2. Any picture that can be used as a wallpaper design for the image display device 50 may be used as the picture. A picture including a picture of a predetermined character 70 may be used. A background picture for the character 70 may be a wood grain pattern, an abstract pattern, a solid color pattern, an illustration, or the like. The character 70 is not particularly limited, and any character such as an animal, a person, or an anime character may be used. Note that a picture without a character 70 may also be used. The size of the printed material 2 has a shape and size that corresponds to the display unit 53 so as to cover substantially the entire surface of the display unit 53 of the image display device 50.

[0127] As shown in FIG. 18(a), the printed material 2 is disposed to cover the display unit 53 when viewed from the front of the display unit 53. The printed material 2 transmits light from the display unit 53 when an image on the display unit 53 is displayed. The printed material 2 conceals the display unit 53 with the image of the printed material 2 when the display unit 53 is turned off. FIG. 18(a) shows the state when the display unit 53 is turned off. As shown in FIG. 18(a), the printed material 2 conceals the display unit 53 and displays the image of the printed material 2 as visual information V1. In this example, an image of a character 70 is displayed as the visual information V1. FIG. 18(b) shows the state when the display unit 53 is illuminated. As shown in FIG. 18(b), the printed material 2 displays light transmitted through the printed material 2 from the display unit 53 as visual information V3. At this time, the image GF displayed by the display unit 53 is displayed as the visual information V3 instead of the image of the character 70.

[0128] Fig. 19 is a cross-sectional view of the protective sheet 100. As shown in Fig. 19, the printed matter 2 is arranged to cover the display unit 53. The protective sheet 100 is laminated on the surface 53a of the display unit 53. The protective sheet 100 has the printed matter 2 and an adhesive layer 101. The printed matter 2 is bonded to the surface 53a of the display unit 53 via the adhesive layer 101.

[0129] 20, when a large display device is used as the image display device 250, a protective sheet 100 is attached so as to cover the entire surface of a display unit 253 provided on the front surface of a main body 252. In this case, when the large display device is not in use, the area of ​​the black screen becomes large and noticeable, but by using the protective sheet 100, the aesthetic appearance of the room can be improved when the display device is not in use. In the case of a TV, the TV may be embedded in the wall, and the exposed display unit 253 may be covered with the protective sheet 100.

[0130] Next, the functions and effects of the protective sheet 100 according to this embodiment will be described.

[0131] The protective sheet 100 protects the display unit 53 of the image display device 50, which displays an image, and also includes the printed matter 2. The printed matter 2 transmits light from the image display device 50 when the image display device 50 displays an image. Therefore, when an image is displayed on the display unit 53, the user can see the image. On the other hand, the printed matter 2 conceals the display unit 53 with the image of the printed matter 2 when the display unit 53 is turned off. Therefore, the user can see the image of the printed matter 2, not the display unit 53 when it is turned off. If such an image were displayed as the image on the display unit 53, power would be consumed. In contrast, using the image of the printed matter 2 can save energy. As described above, the design of the display unit 53 can be improved even when the display unit 53 is not displaying an image.

[0132] In the protective sheet 100, the image display device 50 may be a touch panel type mobile terminal. In this case, the design of the display unit 53 of the mobile terminal can be improved.

[0133] In the protective sheet 100, the design of the printed matter 2 includes a picture of a predetermined character 70, and when the display unit 53 is turned off, the printed matter 2 displays the picture of the character 70 as visual information, and when an image is displayed on the display unit 53, the printed matter 2 displays the image as visual information in place of the picture of the character 70. In this case, the picture of the character 70 can be seen on the display unit 53 when it is turned off, thereby improving the design.

[0134] The present invention is not limited to the above-described embodiments.

[0135] The protection sheet 100 does not necessarily have to be provided on the entire surface of the display unit, but may cover only a partial area. For example, a protection sheet with a border of the character 70 may be used. [Explanation of symbols]

[0136] 2...printed matter, 50...image display device, 53...display unit, 100...protective sheet

Claims

1. A protective sheet for protecting a display unit of an image display device that displays an image, the protective sheet includes a printed matter having a picture printed thereon, The printed matter is When the image is displayed on the display unit, light from the display unit is transmitted; A protective sheet that conceals the display unit with the image of the printed matter when the display unit is turned off.

2. The protection sheet according to claim 1 , wherein the image display device is a touch panel type mobile terminal.

3. the design of the printed matter includes a picture of a predetermined character, The printed matter is When the display unit is turned off, a picture of the character is displayed as visual information; The protection sheet according to claim 1 , wherein when the image is displayed on the display unit, the image is displayed as visual information in place of a picture of the character.

Citation Information

Patent Citations

  • Protection film set of smartphone

    JP2016208138A