JP2014142496A - Front side substrate and manufacturing method of front side substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a front side substrate that is excellent in both concealability and designability in a non-display area.SOLUTION: A front side substrate 50 comprises: a display area A1 that is arranged on an observer side of a rear side substrate 40 to form a display cell 30 with the rear side substrate and displays images; and a non-display area A2 that is a periphery of the display area. The front side substrate has a translucent base material 51, a decorative layer 61 in white or chromatic color that is provided in the non-display area on one side of the translucent base material, and a metallic layer 62 that is provided in the non-display area on the decorative layer opposite to the translucent base material.

Description

  The present invention relates to a front-side substrate that is arranged on the viewer side of a back-side substrate and constitutes a display cell together with the back-side substrate, and a display cell and a display device having the front-side substrate. The present invention also relates to a method for manufacturing a front substrate.

  For example, as disclosed in Patent Document 1, in a recent display device, on a viewer side of a display cell (display panel), a display area for displaying an image and a non-display formed so as to surround the display area A front plate including a region may be disposed. As one of the reasons for using the front plate together with the display cell, an improvement effect of design properties is expected.

  Usually, as shown in FIGS. 14 and 15, the display cell 130 has a non-display area Aa2 also called a frame area around the display area Aa1 for displaying an image. In the non-display area Aa2, wiring and the like are arranged. For this reason, in the device 110A in which the front plate 100 is not used, the case 112A that accommodates the display cell 130 extends the peripheral edge of the front surface of the device 110A and hides the non-display area Aa2 of the display cell 130 from the front. On the other hand, as shown in FIGS. 16 and 17, in the device 110B provided with the front plate 100, by providing the front plate 100 with a concealing function, the case 112B does not need to cover the front surface of the device over a wide range. That is, if the concealment layer 101 is formed on the back surface of the front plate 100, the front surface of the device can be defined by the flat surface defined by the surface of the front plate, and the design is greatly improved. be able to. In addition, like the case, the front plate 100 can be provided with a pattern 103 such as a figure.

JP 2011-194799 A

  However, when the front plate is provided on the viewer side of the display cell, the manufacturing cost of the device including the display cell directly increases. Furthermore, the number of refractive index interfaces located on the viewer side of the display cell inevitably increases. For this reason, the contrast decreases due to the reflection of external light and the transmittance of image light decreases, leading to a significant deterioration in image quality.

  On the other hand, various typical display cells such as a liquid crystal display panel, an organic electroluminescence panel, and a plasma display panel have a pair of substrates disposed to face each other. Among these, if the function of concealing the non-display area can be given to the front substrate located on the viewer side, it is possible to ensure excellent design while eliminating the front plate.

  The inventors have confirmed this point, and by providing a black layer in the non-display area of the front substrate, the non-display area of the display cell can be hidden without providing a front plate. It was. However, when the non-display area of the front substrate is limited to black, the design cannot be improved in combination with a device including a display cell. Moreover, it cannot respond to various needs in design, and it cannot be said that the designability can be improved from this point.

  On the other hand, if the non-display area of the front substrate is made to exhibit sufficient concealment by a layer other than black, that is, a white or chromatic layer, the thickness of the layer increases. In this case, in the liquid crystal display panel, a large step occurs in the vicinity of the boundary between the non-display area and the display area of the front-side substrate, and the rubbing process to the alignment film cannot be performed with high accuracy. Since the gap between the front side substrate and the rear side substrate becomes large and the light distribution action by the alignment film is not effectively exerted on the liquid crystal molecules, alignment defects of the liquid crystal molecules occur. When alignment defects of liquid crystal molecules occur, image light cannot be projected from only desired pixels, and image quality is significantly deteriorated.

  In addition, when the separation distance between the front substrate and the rear substrate in the display area is increased, the light traveling obliquely moves greatly in the pixel arrangement direction. As a result, so-called light leakage occurs in which image light is emitted from pixels other than the desired pixel. In this case, the resolution and color reproducibility are lowered, and the image quality is greatly lowered. In particular, in recent years, high definition of pixels and thinning of the black matrix are rapidly progressing, and such a problem becomes remarkable.

  The present invention has been made in consideration of the above points, and is a front-side substrate that is arranged on the viewer side of the back-side substrate and constitutes a display cell together with the back-side substrate. An object of the present invention is to provide a front-side substrate that is excellent in both concealability and designability in a region.

The front substrate according to the present invention is:
A front-side substrate that is arranged on the viewer side of the back-side substrate so as to form a display cell together with the back-side substrate, and includes a display area for displaying an image and a non-display area around the display area Because
A translucent substrate;
A white or chromatic decorative layer provided in the non-display area on one side of the translucent substrate;
A metal layer provided in the non-display area on the side opposite to the translucent substrate of the decorative layer.

  The front substrate according to the present invention may further include a side light-shielding layer disposed to face a side end face of the decorative layer facing the display area.

  The front substrate according to the present invention may include a light shielding layer provided in the non-display area on the opposite side of the metal layer from the decorative layer.

The front substrate according to the present invention is
A color filter layer provided in the display region to be the one side of the translucent substrate;
The color filter layer may include a black matrix made of the same material as the light shielding layer.

  The front substrate according to the present invention further includes an auxiliary metal layer formed of the same material as the metal layer in the same pattern as the black matrix between the black matrix and the translucent substrate. You may do it.

  In the front substrate according to the present invention, the metal layer may include at least one of chromium, aluminum, magnesium, silver, and alloys thereof.

  The front substrate according to the present invention may further include a resin intermediate layer provided adjacent to the decoration layer and the metal layer between the decoration layer and the metal layer.

  In the front side substrate according to the present invention, the decorative layer may include a main portion made of a resin and titanium oxide dispersed in the main portion.

A display cell according to the present invention comprises:
Any of the front substrate according to the present invention described above;
And a back side substrate disposed to face the front side substrate.

  The display device according to the present invention includes any of the display cells according to the present invention described above.

A method for manufacturing a front substrate according to the present invention includes:
A front-side substrate that is arranged on the viewer side of the back-side substrate so as to form a display cell together with the back-side substrate, and includes a display area for displaying an image and a non-display area around the display area A manufacturing method of
A step of forming a white or chromatic decorative layer in the non-display region on one side of the translucent substrate;
On the translucent base material on which the decorative layer is formed, from the side where the decorative layer is formed, forming a metal film by sputtering;
Forming a resist pattern made of a light-shielding material on the opposite side of the metal film from the translucent substrate, and patterning the metal film in both the display area and the non-display area; Including
The patterned metal film is a metal layer formed in a region overlapping the decorative layer in the non-display region,
The resist pattern having a light shielding property defines a pixel as a black matrix in the display region, and forms a light shielding layer formed in a region overlapping the metal layer in the non-display region.

  In the method for manufacturing a front side substrate according to the present invention, the resist pattern having the light shielding property is a side light shielding arranged in the non-display area so as to face a side end face facing the display area side of the decorative layer. You may make it a layer.

  ADVANTAGE OF THE INVENTION According to this invention, the front side board | substrate can exhibit the designability which was excellent, and the concealment property in a non-display area | region.

FIG. 1 is a diagram for explaining an embodiment of the present invention, and is a plan view showing a device including a display device. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 3 is an enlarged view of the same cross section as FIG. 2 of the display device included in the apparatus of FIG. FIG. 4 is a diagram for explaining an example of a method for manufacturing the front substrate of the display device shown in FIG. FIG. 5 is a diagram for explaining an example of a method for manufacturing the front side substrate of the display device shown in FIG. 3, and is a diagram showing a process performed after the process of FIG. FIG. 6 is a diagram for explaining an example of a method for manufacturing the front side substrate of the display device shown in FIG. 3, and is a diagram showing a process performed after the process of FIG. FIG. 7 is a view for explaining an example of a method for manufacturing the front side substrate of the display device shown in FIG. 3, and is a view showing a process performed after the process of FIG. FIG. 8 is a graph showing the transmittance of a thin film made of white. FIG. 9 is a cross-sectional view showing a modification of the front substrate. FIG. 10 is a diagram for explaining a modification of the method for manufacturing the front substrate. FIG. 11 is a diagram for explaining a modification of the method for manufacturing the front side substrate, and is a diagram illustrating a process performed after the process of FIG. 10. FIG. 12 is a diagram for explaining a modification of the method for manufacturing the front substrate, and is a diagram illustrating a process performed after the process of FIG. 11. FIG. 13 is a diagram for explaining a modification of the method for manufacturing the front side substrate, and is a diagram illustrating a process performed after the process of FIG. 12. FIG. 14 is a plan view for explaining an example of a device including a conventional display device. 15 is a longitudinal sectional view showing the apparatus of FIG. FIG. 16 is a plan view for explaining another example of a device including a conventional display device. 17 is a longitudinal sectional view showing the apparatus of FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product. In addition, as used in the present specification, the shape and geometric conditions and the degree thereof are specified, for example, terms such as “parallel”, “orthogonal”, “identical”, etc. are not bound to a strict meaning. Therefore, it should be interpreted to include a range where a similar function can be expected.

  FIGS. 1-13 is a figure for demonstrating one Embodiment and its modification by this invention. Below, the example which applied the display cell containing the front side board | substrate and front side board | substrate by this invention to the display apparatus for portable terminals is demonstrated. In the following example, the display cell forms a liquid crystal display panel. However, the front substrate and the display cell according to the present invention can be applied to various devices including the display cell without being limited to the portable terminal, and may constitute a display cell other than the liquid crystal display panel. Good. Note that the “display cell” in this specification refers to a configuration that includes a pair of substrates arranged to face each other and defines a plurality of pixels serving as unit elements for forming an image.

  1 and 2 are a plan view and a longitudinal sectional view showing the mobile terminal 11 including the display device 20, respectively. FIG. 3 is a partially enlarged view of the vertical cross-sectional view of FIG. 2, showing the display cell 30 included in the display device 20, particularly the front substrate 50 of the display cell 30. 4 to 7 show an example of a method for manufacturing the front side substrate 50.

  As shown in FIGS. 1 and 2, the device 10 configured as the mobile terminal 11 includes a display device 20 and a case 12 that houses the display device 20. The display cell 30 of the display device 20 defines a display area A1 (a rectangular area surrounded by a dotted line in FIG. 1) in which an image is displayed and a non-display area A2 that surrounds the display area A1. To do. As will be described in detail below, the front substrate 50 included in the display cell 30 can exhibit excellent concealability in the non-display area A2. Therefore, unlike the conventional example shown in FIGS. 14 and 15, the case 12 only needs to support the display cell 30 from the side, and it is not necessary to cover the non-display area A2 of the display cell 30 on the front surface of the device 10. Absent. As a result, the case 12 is hardly exposed on the front surface of the device 10 and can be formed as a flat surface without a step defined by the front substrate 50 of the display cell 30. For this reason, the device 10 is excellent in design. Further, unlike the conventional example shown in FIGS. 16 and 17, it is not necessary to provide a front plate separately from the display cell 30, which is excellent in cost, weight, thinness and the like.

  Note that the device 10 appropriately includes a circuit and the like necessary for functioning as the mobile terminal 11, but illustration thereof is omitted. The configuration for functioning as the mobile terminal 11 can be the same as a known configuration. Therefore, the description about the structure for functioning as the portable terminal 11 is omitted. Hereinafter, the display device 20 supported by the case 12 will be described.

  In the illustrated example, the display device 20 constitutes a liquid crystal display device. The display device 20 includes a display cell 30 that forms a liquid crystal display panel, and a backlight 25 that illuminates the display cell 30 from the back side. As the backlight 25, for example, a surface light source device such as an edge light type or a direct type can be appropriately used. The display cell 30 can display an image on the display surface by selecting and transmitting the planar light illuminated from the backlight 25 for each pixel.

  As well shown in FIG. 3, the display cell 30 as a liquid crystal display panel includes a back side substrate 40 disposed on the back side (backlight side) and a front surface disposed opposite to the back side substrate 40. A side substrate 50 and a liquid crystal layer 35 sealed between the back side substrate 40 and the front side substrate 50 are provided. The front substrate 50 has a configuration for displaying an image together with other members that together form the display cell 30. In addition, 50 described here also has a configuration for improving the design of the device 10 and the display device 20 while concealing the wiring and the like arranged in the non-display area A2 of the display cell 30.

  First, a configuration for displaying an image of the display cell 30 will be described, and then the device 10 and the display device 20 while concealing the wiring and the like arranged in the non-display area A2 of the display cell 30 with respect to the front substrate 50. The structure for improving the designability of will be described.

  The front substrate 50 includes a translucent substrate 51 having translucency for visible light, a color filter layer 52 provided in the display surface area A1 which is one side of the translucent substrate 51, and have. In the example shown in FIG. 3, the color filter layer 52 has a black matrix 53 formed on the surface facing the back side of the translucent substrate 51. The black matrix 53 is formed on the translucent substrate 51 in a predetermined matrix pattern, and defines a large number of opening areas. Each opening area forms a pixel which is a unit element for forming an image. A colored portion 54 (54R, 54G, 54B) colored in the display color of the pixel is formed in the opening region. An image is formed by the light transmitted through the colored portion (colored layer) 54.

  Further, the front side substrate 50 is appropriately provided with other components in order to effectively function as a viewer side substrate (counter substrate) of the liquid crystal display panel. For example, as shown in FIG. 3, a protective layer 56 and an alignment film 58 are formed in this order on the color filter layer 52 toward the liquid crystal layer 35 side. Further, a polarizing plate (not shown) is laminated on the side of the front substrate 50 opposite to the liquid crystal layer 35 of the translucent substrate 51, that is, on the viewer side of the translucent substrate 51 of the front substrate 50. Yes. Further, since the front substrate 50 forms a display surface, various layers such as an antireflection layer, an antistatic layer, and an antiglare layer are provided on the viewer side of the translucent substrate 51, for example. May be.

  On the other hand, as shown in FIG. 3, the back side substrate 40 is a region facing the back side base material 41 having visible light transmissivity and the colored portions 54 of the front side substrate 50 on the back side base material 41. Each of these is provided with a pixel electrode 42. For each pixel electrode 42, a switching element (not shown) for controlling voltage application to the pixel electrode 42 is provided separately. The switching element can be formed as a thin film transistor (TFT). Various circuit wirings such as scanning lines and signal lines (data lines) necessary for driving the switching elements are provided in the area facing the black matrix and the non-display area A2 in the display area A1 of the back substrate 40 (see FIG. (Not shown) is formed.

  Further, the back side substrate 40 is appropriately provided with other components in order to effectively function as a backlight side substrate (element substrate, array substrate) of the liquid crystal display panel. For example, as shown in FIG. 3, a protective layer 43 and an alignment film 44 are formed in this order on the pixel electrode 42 toward the liquid crystal layer 35 side. In addition, a polarizing plate (not shown) is laminated on the side of the back side substrate 40 opposite to the liquid crystal layer 35 of the back side substrate 41, that is, on the backlight side of the back side substrate 41 of the back side substrate 40. ing.

  Next, the configuration of the front-side substrate 50 for improving the design of the device 10 and the display device 20 while concealing the circuit wiring and the like arranged in the non-display area A2 of the display cell 30 will be described.

  As shown in FIG. 3, the front substrate 50 includes a white or chromatic decorative layer 61 provided in the non-display area A <b> 2 on one side of the translucent substrate 51, and the decorative layer 61. And a metal layer 62 provided in the non-display area A <b> 2 on the side opposite to the translucent substrate 51. In the illustrated example, the decorative layer 61 is formed over the entire range of the non-display area A <b> 2 on the surface facing the back side of the translucent substrate 51. Further, in the illustrated example, the metal layer 62 is formed on the surface facing the back side of the decorative layer 61 so as to cover the entire surface. That is, in the illustrated form, the elements are arranged from the observer side in the order of the translucent substrate 51, the decorative layer 61, and the metal layer 62.

  As described above, the back substrate 40 includes circuit wiring and the like in the non-display area A2. For this reason, the front side board | substrate 50 needs to have shielding property. According to the front-side substrate 50 described here, the transmittance for visible light in the laminated portion of the decorative layer 61 and the metal layer 62 can be expressed as an optical density (OD) and can be 4 or more. It was confirmed that the transmittance could be reduced.

  An observer who observes the display device 20 (display cell 30) including the front substrate 50 can observe the decorative layer 61 through the translucent substrate 51. For this reason, the decorative layer 61 can also impart excellent design properties to the display device 20. On the other hand, an observer who observes the display device 20 (display cell 30) does not visually recognize the metal layer 62 covered with the decorative layer 61. Reflection of an external image to the non-display area A2 adjacent to the display area A1 by covering the metal layer 62, which tends to have a higher reflectance than the decoration layer 61, with the decorative layer 61 having an excellent design. It is possible to effectively prevent the image from being displayed and to effectively avoid the deterioration of the image displayed in the display area A1.

Note that the transmittance value (OD) represented by the optical density in this specification is “log ₁₀ (Iin / Iin /) using the intensity Iin of incident light that is vertically incident and the intensity Iout of transmitted light that is vertically transmitted. Iout) ".

  Further, as shown in FIG. 3, the illustrated front side substrate 50 includes a light shielding layer 63 provided in a non-display area A2 on the side opposite to the decorative layer 61 of the metal layer 62, and a decorative layer. And a side light shielding layer 64 that covers the side end face 61a facing the display area A1 side of 61 from the side (direction along the plate surface of the front substrate 50). In the non-display area A2 on the opposite side of the light shielding layer 63 from the metal layer 62, the protective layer 56 and the alignment film 58 described above are arranged in this order. For this reason, in the illustrated example, the translucent substrate 51, the decorative layer 61, the metal layer 62, the light shielding layer 63, the protective layer 56, and the alignment film 58 are arranged in this order.

  Here, the light shielding layer 63 is a layer whose main purpose is to prevent light from entering the metal layer 62 from the back side, and contributes to improving the shielding property in the non-display area A2, but has a shielding property. It is not a layer provided mainly for improvement. As will be described later, the shielding property in the non-display area A <b> 2 of the display cell 30 can be ensured to a sufficient extent by the decorative layer 61 and the metal layer 62.

  Furthermore, in the illustrated example, a pattern portion 68 that displays a product name and a manufacturing name is formed between the translucent substrate 51 and the decorative layer 61. Such a pattern part 68 can be formed by printing on the translucent base material 51 before forming the decoration layer 61 as an example. The pattern portion 68 is not limited to characters and symbols for displaying information, but may be a pattern or a pattern.

  Hereinafter, the decorative layer 61, the metal layer 62, the light shielding layer 63, and the side light shielding layer 64 will be described in order.

  The decorative layer 61 is formed as a white or chromatic layer. A chromatic color is a color that is distinguished from an achromatic color that has no color and has only lightness, that is, a chromatic color is a color that has a hue such as red, green, and blue and has lightness, hue, and saturation. .

  By observing the decorative layer 61 made of white or chromatic color through the translucent substrate 51, it is possible to widen the design width in the appearance of the device 10 in which the display cell 30 is incorporated, and as a result. The design of the device 10 can be effectively increased. In this regard, the decorative layer 61 may be formed using a plurality of colors. Moreover, you may make it form the pattern part 68 mentioned above by forming the decoration layer 61 using a several color.

  The illustrated decorative layer 61 is formed so as to cover the entire surface of the metal layer 62 from the observer side, but is not limited thereto. The decorative layer 61 may not be formed in a part of the non-display area A2, and the metal layer 62 may be exposed to the viewer side in this non-formed part. It is also possible to improve the design of the display device 20 by the metal layer 62 exposed in a part. Further, the pattern portion 68 may be formed by the metal layer 62 exposed in part.

  Such a decoration layer 61 is formed as a coating film including a main part made of a resin binder as a cured product of a photosensitive resin, and a pigment dispersed in the main part. Typically, the decorative layer 61 can be formed as a pigment-dispersed resist coating film. The thickness of the decorative layer 61 is set to be 1.0 μm or more and 3.0 μm or less from the viewpoint of exhibiting a sufficient color and reducing the gap between the substrates 40 and 50 in the display cell 30. it can. In addition, in the front side board | substrate 50 demonstrated here, the shielding property in non-display area | region A2 is made into sufficient grade by the combination of the decoration layer 61 and the metal layer 62. FIG. Accordingly, the shielding property of the decorative layer 61 alone is not particularly limited, and can be, for example, 0.5 to 1.2 in terms of optical density.

  The metal layer 62 is a layer made of a metal and exhibits extremely excellent shielding properties as compared with the pigment-dispersed resist coating film. Therefore, the metal layer 62 can be a metal thin film made of vapor, such as sputtering or vapor deposition, such as chromium, aluminum, magnesium, or silver.

  For the purpose of providing sufficient shielding for the non-display area A2, it is desired that the transmittance of the front substrate 50 in the non-display area A2 is 4 or more in terms of optical density OD. On the other hand, the transmittance in the decorative layer 61 and the metal layer 62 naturally varies depending on the thickness. Then, when the present inventors confirmed by experiment, in the combination with the decoration layer 61 of the thickness of 1.0 micrometer or more-3.0 micrometers or less mentioned above, if the thickness of the metal layer 62 shall be 1000 to 1800 inches, The transmittance in the non-display area A2 of the front substrate 50 could be sufficiently 4 or more with the optical density OD.

  In addition, in FIG. 8, the result of having investigated the transmittance | permeability of the decoration layer 61 single by changing the thickness of the decoration layer 61 is shown. In the investigation whose results are shown in FIG. 8, a plurality of white decorative layers 61 containing titanium oxide as a pigment are produced with varying thicknesses, and the transmittance of each decorative layer 61 is measured using a microspectrophotometer. It was measured. From the results shown in FIG. 8, the white decorative layer 61 alone has a thickness that is thin enough to prevent the above-described alignment failure of the liquid crystal molecules (1.0 μm or more and 3.0 μm or less), and the transmittance is changed to the optical density OD. Thus, it was impossible to make the number 4 or more sufficiently.

  The inventors also investigated changes in color and reflectance resulting from providing the metal layer 62 on the back side of the decorative layer 61. Samples A1, B1, and C1 to be investigated are a white decorative layer containing titanium oxide as a pigment on a base material made of glass, a metal layer made of 1500-thick chromium formed by sputtering, Were formed in order. The thickness of the decoration layer was changed as shown in Table 1 between Samples A1, B1, and C1. Samples A1, B1, and C1 were configured identically in other respects except for the thickness of the decorative layer. Samples A2, B2, and C2 to be investigated were produced by forming a white decorative layer containing titanium oxide as a pigment on a glass substrate. The thickness of the decoration layer was changed as shown in Table 1 between Samples A2, B2, and C2. Samples A2, B2, and C2 were configured the same as Samples A1, B1, and C1, respectively, except that no metal layer was formed. Further, a front plate that is incorporated in the observer side of the liquid crystal cell as a separate body from the liquid crystal display cell in a commercially available smartphone, and the front plate in which the non-display area is white was set as Sample D. In sample D, the thickness of the white decorative layer was 50 μm, and no metal layer was provided.

  Using a spectrocolorimeter (CM-2500d, Konica Minolta Co., Ltd.), the reflected light from each sample when light is incident from the side of the translucent substrate is an XYZ color system based on JIS-Z8701. Expressed in The results are shown in Table 1. As can be understood from the results in Table 1, it was confirmed that the color and reflectance of the reflected light did not change depending on the presence or absence of the metal layer. Moreover, it was confirmed that samples A1, A2, and A3 including a metal layer can realize the same color and reflectance as those of the commercially available sample D.

  In addition, when the decoration layer 61 is formed in a chromatic color in combination with the metal layer 62 having a metallic luster, the scattering component in the decoration layer 61 itself is reduced unlike the white decoration layer. The decorative layer 61 in the case where the decorative layer 61 is observed through the conductive substrate 51 can be made metallic. In this case, the design of the display device 20 (display cell 30) in which the front substrate 50 is incorporated can be effectively improved. In addition, as described later, it is preferable that reflection on the back surface of the metal layer 62 is suppressed from the viewpoint of preventing generation of stray light or the like. For this reason, it is preferable that only the surface of the metal layer 62 facing the decorative layer 61 is formed as a metallic gloss surface.

  Next, the light shielding layer 63 and the side light shielding layer 64 will be described. The light shielding layer 63 and the side light shielding layer 64 are both layers having a function of shielding visible light.

  As described above, the light shielding layer 63 is provided in the non-display area A <b> 2 on the opposite side of the metal layer 62 from the decorative layer 61. The light shielding layer 63 prevents light from entering the metal layer 62 from the back side. When light enters the metal layer 62 having a relatively high reflectance, stray light is generated in the display cell 30. This stray light not only lowers the contrast of the image but also causes a malfunction of the switching element provided on the rear substrate 40. According to the light shielding layer 63, the occurrence of such stray light can be effectively prevented, and the image quality displayed by the display device 20 can be improved.

  In addition, external light or the like incident on the front substrate 50 from the side of the translucent substrate 51 may be scattered by the decorative layer 61. Such a phenomenon is more likely to occur when, for example, highly reflective particles or pigments such as titanium oxide are included in the decorative layer 61. When this phenomenon occurs, a part of the light scattered by the decoration layer 61 is colored near the edge of the display area A1 via the side end face 61a facing the display area A1 side of the decoration layer 61. 54 may be incident. In this case, a problem of light leakage occurs in the vicinity of the edge of the display area A1, and the display image quality on the display device 20 is deteriorated. As described above, the side light shielding layer 64 covers the side end face 61a of the decorative layer 61 facing the display area A1 side from the display area A1 side along the plate surface of the front substrate 50. For this reason, the side light shielding layer 64 can effectively prevent a part of the light scattered by the decoration layer 61 from proceeding to the display area A1, and can improve the image quality displayed by the display device 20. .

  The light shielding layer 63 and the side light shielding layer 64 are formed, for example, as a coating film including a main portion made of a resin binder as a cured product of a photosensitive resin, and light absorbing particles dispersed in the main portion. . Typically, a black pigment such as titanium black or carbon black can be used as the light absorbing particles, and the light shielding layer 63 and the side light shielding layer 64 can be formed as a pigment-dispersed resist coating film. In the illustrated example, the light shielding layer 63 and the side light shielding layer 64 are integrally formed using the same material. Further, in the illustrated example, the light shielding layer 63 and the side light shielding layer 64 are also formed integrally with the black matrix 53 of the color filter layer 52 using the same material. Such a front substrate 50 can be formed at low cost.

  In the illustrated example, a protective layer 56 and an alignment film 58 extending from the display area A1 to the non-display area A2 are disposed on the back side of the light shielding layer 63.

  The alignment film 58 is rubbed. At this time, if a large step is formed on the surface of the alignment film 58, it is difficult to accurately perform the rubbing process in the step portion. In this case, alignment defects occur in the liquid crystal molecules contained in the liquid crystal layer 35, and the light emission for each pixel in the display cell 30 cannot be controlled with high accuracy. In the illustrated example, a step having a height corresponding to the total thickness of the decorative layer 61 and the metal layer 62 is generated between the display area A1 and the non-display area A2. However, the metal layer 62 is an extremely thin layer, and the decorative layer 61 can be formed as a sufficiently thin layer because the shielding property by itself is not questioned. For this reason, the alignment defect of a liquid crystal molecule can be avoided effectively.

  Here, with reference to FIGS. 4-7, an example of the method of manufacturing the front side board | substrate 50 of the structure mentioned above is demonstrated.

  First, a translucent substrate 51 having transparency to visible light is prepared. As the translucent substrate 51, typically, glass excellent in terms of transmittance and strength can be used. Examples of the glass include chemically strengthened glass. Moreover, as the translucent substrate 51 other than glass, a resin substrate made of an acrylic resin, a polycarbonate resin, a cycloolefin resin, or the like can be used.

  Next, as shown in FIG. 4, a decoration layer 61 is formed in an area that forms the non-display area A <b> 2 on the translucent substrate 51. For example, the decoration layer 61 as a layer formed by dispersing a pigment in a main part as a resin binder is produced using a photolithography technique as follows. First, a photosensitive composition containing a resin and a pigment that will form the main part is applied onto the translucent substrate 51. Next, for example, only a region where the decorative layer 61 is to be formed is exposed in a predetermined pattern, and then developed. As described above, the decorative layer 61 can be formed on the translucent substrate 51 in a predetermined pattern.

  Next, as shown in FIG. 5, in the example described here, only on the decorative layer 61, in the area that forms the non-display area A <b> 2 on the translucent substrate 51 on which the decorative layer 61 is formed. Then, the metal layer 62 is formed. Specifically, first, a metal thin film is formed by sputtering over the entire surface of the translucent substrate 51 on the side where the decorative layer 61 is formed. As an example, a thin film made of chromium having a thickness of 1500 mm is formed. Next, a resist pattern film patterned using a photolithographic technique is formed on the metal thin film. Thereafter, the metal thin film is patterned by etching the metal thin film using the resist pattern film as a mask. Next, the resist pattern film that has become unnecessary is removed. By the above procedure, the metal layer 62 is produced in an area that forms the non-display area A2 on the translucent substrate 51 on which the decorative layer 61 is formed.

  Next, as shown in FIG. 6, the light shielding layer 63 and the side light shielding layer 64 are formed in an area that forms the non-display area A <b> 2 on the translucent substrate 51 on which the decorative layer 61 and the metal layer 62 are formed. And the black matrix 53 of the color filter layer 52 is formed in an area that forms the display area A1 on the translucent substrate 51. For example, the light shielding layer 63, the side light shielding layer 64, and the black matrix 53 as a layer formed by dispersing a pigment in a main part as a resin binder are manufactured using a photolithography technique as follows. Can do.

  First, a photosensitive composition containing a resin and a pigment that form the main part is applied onto the translucent substrate 51 from the side on which the decorative layer 61 and the metal layer 62 are formed. Next, exposure is performed in a predetermined pattern, and then development is performed. As described above, the light shielding layer 63, the side light shielding layer 64, and the black matrix 53 can be produced on the side of the translucent substrate 51 where the decorative layer 61 and the metal layer 62 are formed. The obtained light shielding layer 63, side light shielding layer 64, and black matrix 53 are integrally formed. According to the above method, since the light shielding layer 63, the side light shielding layer 64, and the black matrix 53 can be simultaneously manufactured using the same material, it is very preferable in terms of manufacturing cost.

  Thereafter, a colored portion 54 is formed in the opening area defined by the color filter layer 52 of the black matrix 53 (see FIG. 7). The colored portion 54 can be formed as a pigment-dispersed resist coating film in the same manner as a normal color filter. As shown in the example, when the colored portion 54 includes a plurality of types of colored portions such as the red portion 54R, the green portion 54G, and the blue portion 54B, the pigment is changed for each type of colored portion, Make it.

  Thereafter, the protective layer 56 and the alignment film 58 are produced, and the front side substrate 50 is obtained. The protective layer 56 and the alignment film 58 can be produced in the same manner as a known method.

  In the display cell 30, the display device 20 and the device 10 using the front substrate 50 as described above, the following operational effects can be obtained.

  The front substrate 50 arranged on the front side (observer side) of the pair of substrates included in the display cell 30 is a translucent substrate 51 and a non-transparent substrate 51 on one side. A white or chromatic decorative layer 61 provided in the display area A2, and a metal layer 62 provided in the non-display area A2 on the opposite side of the transparent layer 51 of the decorative layer 61; ,have.

  Since the front-side substrate 50 includes the metal layer 62 having excellent shielding properties in the non-display area A2, the non-display area A2 of the display cell 30 is supported by the case 12 that supports the display cell 30 (display device 20). It is possible to hide the opaque circuit wiring arranged in the non-display area A2 of the display cell 30 without covering the display cell 30 with a separate front plate. For this reason, the case 12 only needs to support the display cell 30 from the side, and the case 12 does not need to extend to the front surface of the display device 20. For this reason, most of the front surface of the display device 20 is defined by the front substrate 50 of the display cell 30, and an appearance rich in design is imparted to the display device 20 and the device 10 (mobile terminal 11). can do. In particular, as in the above-described embodiment, when the decorative layer 61 and the metal layer 62 are located on the back side of the front substrate 50, the display cell 30 (display device 20) defined by the front substrate 50 is used. The surface is formed as a flat and transparent surface without distinction between the display area A1 and the non-display area A2, and excellent design properties are exhibited. Moreover, since it is not necessary to use a front plate separate from the display cell 30, the manufacturing cost of the display device 20 and the device 10 (the portable terminal 11) can be directly reduced. Further, by omitting a separate front plate, the thickness of the display device 20 and the device 10 (the portable terminal 11) can be reduced, and the display device 20 and the device 10 (the portable terminal 11) can be reduced in weight. Can do.

  In addition, a white or chromatic decorative layer 61 is provided in the non-display area A <b> 2 between the translucent substrate 51 and the metal layer 62 of the front substrate 50. When the front substrate 50 is arranged so that the translucent substrate 51 of the front substrate 50 is on the viewer side and the metal layer 62 is on the back surface, the decorative layer 61 covers the metal layer 62. . The decorative layer 61 can meet various design needs by using white and chromatic colors. As a result, the display device 20 and the device 10 (the portable terminal 11) are provided with excellent design. can do. Moreover, it is also possible to form the pattern part 68 between the translucent base material 51 and the decoration layer 61, and also design nature can be improved. In addition, since the metal layer 62 that tends to have a higher reflectance than the decorative layer 61 is covered with the decorative layer 61, the metal layer 62 is used to improve the concealment, and the exterior to the front substrate 50. It is also possible to prevent image reflection.

  Moreover, in the front side board | substrate 50 demonstrated here, the concealability in the non-display area | region A2 is maintained not only by the decoration layer 61 but by the decoration layer 61 and the metal layer 62. FIG. Therefore, it is not necessary to increase the thickness of the decorative layer 61 in order to improve the concealability of the decorative layer 61 alone, and as described above, the thickness of the decorative layer 61 is 1.0 μm or more to 3.0 μm or less. It can be. On the other hand, since the metal layer 62 is a layer made of metal, the concealability required for the non-display area A2 can be secured together with the decorative layer 61 as a thin film layer of about 1000 to 1800 mm.

  As a result, the thickness in the non-display area A2 of the front side substrate 50 and the thickness in the display area A1 are imparted to the non-display area A2 of the front side substrate 50 while providing excellent shielding properties with a transmittance of 4 or more in optical density. However, it can be made not to differ greatly. As a result, it is possible to effectively prevent a large step from occurring near the boundary between the display area A1 and the non-display area A2 in the surface of the alignment film 58 formed on the back side of the front substrate 50. be able to. Thereby, when the alignment film 58 is rubbed, it is possible to effectively prevent the rubbing accuracy from being lowered near the boundary between the display area A1 and the non-display area A2. That is, the alignment film 58 can be uniformly rubbed over the entire surface. As a result, the liquid crystal molecules of the liquid crystal layer 35 are aligned as planned by the alignment film 58, and a high-resolution image can be displayed while preventing light leakage.

  In addition, since the thickness of the front substrate 50 in the non-display area A2 is not too thick, it is possible to avoid an increase in the gap between the front substrate 50 and the rear substrate 40 in the display area A1. Therefore, the light traveling in the direction inclined with respect to the normal direction of the display cell 30 passes through different pixels on the back side substrate 40 and the front side substrate 50, in other words, the back side substrate 40 through which the light is transmitted. It is possible to effectively prevent the colored portion other than the colored portion of the front substrate 50 facing the pixel electrode 42 from passing through. As a result, only desired pixels can emit light stably, and resolution and color reproducibility can be improved. Such an effect is particularly useful in recent years when high definition of pixels and thinning of the black matrix are rapidly progressing.

  Note that various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted.

  In the above-described embodiment, the example in which the decorative layer 61 and the metal layer 62 are disposed adjacent to each other has been described, but the present invention is not limited thereto. As shown in FIG. 9, a resin intermediate layer 65 provided adjacent to the decorative layer 61 and the metal layer 62 may be further provided between the decorative layer 61 and the metal layer 62. For example, in the case where titanium oxide having a relatively large particle size is dispersed in the decorative layer 61, depending on the pigment and particles dispersed in the decorative layer 61, the translucent substrate 51 of the decorative layer 61 and May have slight irregularities formed on the opposite surface. At this time, due to the very thin film thickness of the metal layer 62, the adhesion of the metal layer 62 to the decorative layer 61 is reduced, or the metal layer 62 is formed on the decorative layer 61. May not be stable. On the other hand, by providing the resin intermediate layer 65, the surface on which the metal layer 62 is to be formed can be made flatter than the surface of the decorative layer 61. Thereby, it becomes possible to improve the adhesiveness between the decoration layer 61 and the metal layer 62, and the metal layer 62 with a very thin thickness can be formed stably. The resin intermediate layer 65 may be integrally formed from the same material as that of the protective layer 56 by appropriately changing the order in which the layers included in the front substrate 50 are manufactured.

  The above-described method for manufacturing the front side substrate 50 is merely an example. As an example, the manufacturing method may be changed as shown in FIGS.

  In the example shown in FIGS. 10 to 13, a white or chromatic decorative layer 61 is provided in the non-display area A <b> 2 on one surface of the translucent substrate 51 in the same manner as the above-described manufacturing method. Form. Next, as shown in FIG. 10, the metal film 72 is formed on the translucent base material 51 on which the decoration layer 61 is formed by sputtering from the side on which the decoration layer 61 is formed. The metal film 72 can be formed in the same manner as the metal thin film for producing the metal layer 62 in the above-described embodiment. Next, as shown in FIG. 11, a resist pattern 73 made of a light-shielding material is formed on the opposite side of the metal film 72 from the translucent substrate 51. Thereafter, the metal film 72 is etched using the resist pattern 73 as a mask, and the metal film 72 is patterned into a pattern similar to the resist pattern 73 as shown in FIG.

  The patterned metal film 72 forms a metal layer 62 formed in a region overlapping with the decoration layer 61 in the non-display region A2. The resist pattern 73 having a light shielding property defines pixels as the black matrix 53 of the color filter layer 52 in the display area A1, and a light shielding layer 63 formed in an area overlapping the metal layer 62 in the non-display area A2. The side light shielding layer 64 that covers the side end surface 61a of the decorative layer 61 from the display area A1 side is formed along the plate surface of the front substrate 50. That is, the resist pattern 73 in this manufacturing method can be formed in the same manner as the light shielding layer 63, the side light shielding layer 64, and the black matrix 53 in the above-described embodiment.

  Thereafter, similarly to the above-described embodiment, a colored portion 54 is formed in the opening region defined by the color filter layer 52 of the black matrix 53 (see FIG. 13). Further, if necessary, the protective layer 56 and the orientation are aligned. A film 58 is produced.

  According to the manufacturing method shown in FIGS. 10 to 13, it is necessary to form a resist pattern film only for patterning the metal film 72 as compared with the manufacturing method described in the above embodiment. Absent. Thereby, the front side board | substrate 50 can be produced more cheaply and more easily. Further, in the front substrate 50 manufactured by the manufacturing method shown in FIGS. 10 to 13, the metal layer is formed between the black matrix 53 and the translucent substrate 51 in the same pattern as the black matrix 53. An auxiliary metal layer 66 made of the same material as that of 62 is formed. According to such an auxiliary metal layer 66, the optical density required for the black matrix 53 can be reduced. Since the black matrix 53 can be thinned, a finer pattern can be formed.

  In addition, although the some modification with respect to embodiment mentioned above was demonstrated above, naturally, it is also possible to apply combining several modifications suitably.

DESCRIPTION OF SYMBOLS 10 apparatus 12 case 20 display apparatus 30 display cell, display panel 40 back side board | substrate 41 back side base material 50 front side board | substrate 51 translucent base material 52 color filter layer 53 black matrix 58 alignment film 61 decorating layer 61a side end surface 62 Metal layer 63 Light-shielding layer 64 Side light-shielding layer 65 Resin intermediate layer 66 Auxiliary metal layer 68 Picture portion 72 Metal film 73 Resist pattern

Claims (12)

A front-side substrate that is arranged on the viewer side of the back-side substrate so as to form a display cell together with the back-side substrate, and includes a display area for displaying an image and a non-display area around the display area Because
A translucent substrate;
A white or chromatic decorative layer provided in the non-display area on one side of the translucent substrate;
A front-side substrate comprising: a metal layer provided in the non-display area on the side opposite to the translucent substrate of the decorative layer.   The front-side substrate according to claim 1, further comprising a side light-shielding layer disposed to face a side end surface facing the display area side of the decoration layer.   The front side board | substrate of Claim 1 or 2 provided with the light shielding layer provided in the said non-display area | region which becomes the opposite side to the said decoration layer of the said metal layer. A color filter layer provided in the display region to be the one side of the translucent substrate;
4. The front substrate according to claim 3, wherein the color filter layer includes a black matrix made of the same material as the light shielding layer.   The front surface according to claim 4, further comprising an auxiliary metal layer formed of the same material as the metal layer in the same pattern as the black matrix between the black matrix and the translucent substrate. Side board.   The said metal layer is a front side board | substrate as described in any one of Claims 1-5 containing at least any one of chromium, aluminum, magnesium, silver, and its alloy.   The front side as described in any one of Claims 1-6 further equipped with the resin intermediate | middle layer provided adjacent to the said decoration layer and the said metal layer between the said decoration layer and the said metal layer. substrate.   The front side substrate according to any one of claims 1 to 7, wherein the decorative layer includes a main portion made of a resin and titanium oxide dispersed in the main portion. The front substrate according to any one of claims 1 to 8,
A display cell comprising: a back side substrate disposed to face the front side substrate.   A display device comprising the display cell according to claim 9. A front-side substrate that is arranged on the viewer side of the back-side substrate so as to form a display cell together with the back-side substrate, and includes a display area for displaying an image and a non-display area around the display area A manufacturing method of
A step of forming a white or chromatic decorative layer in the non-display region on one side of the translucent substrate;
On the translucent base material on which the decorative layer is formed, from the side where the decorative layer is formed, forming a metal film by sputtering;
Forming a resist pattern made of a light-shielding material on the opposite side of the metal film from the translucent substrate, and patterning the metal film in both the display area and the non-display area; Including
The patterned metal film is a metal layer formed in a region overlapping the decorative layer in the non-display region,
The method for manufacturing a front side substrate, wherein the resist pattern having a light shielding property defines pixels as a black matrix in a display region, and forms a light shielding layer formed in a region overlapping the metal layer in the non-display region.   The front surface according to claim 11, wherein the resist pattern having the light shielding property forms a side light shielding layer disposed to face a side end surface of the decorative layer facing the display region in the non-display region. Method for manufacturing side substrate.

Images