Black matrix substrate and display device having the same

Abstract

The black matrix substrate of the present invention comprises: a transparent substrate; a black matrix formed on one surface of the transparent substrate in a first lattice pattern with a line width Ax in a first direction and a line width Ay in a second direction when viewed from above; a first transparent resin layer covering the black matrix; resin walls laminated in a second lattice pattern on the first transparent resin layer with a line width Dx smaller than the line width Ax and co-axially with the line width Ax in the first direction; and a light reflecting layer laminated in the first direction with a line width Cx larger than the line width Dx and co-axially with the line width Ax so as to cover the resin walls. The light reflecting layer has edges with a width Ex symmetrically arranged inwardly of the line width Ax and about the central axis of the line width Ax in the first direction, and a transparent protective layer laminated in the first direction with a line width Bx including two edges with a line width Cx and a width Ex so as to cover the light reflecting layer.

Description

Technical Field

[0001] The present invention relates to a black matrix substrate and a display device having the black matrix substrate.

[0002] This application claims priority based on Japanese Patent Application No. 2020-079289, filed in Japan on April 28, 2020, the contents of which are incorporated herein by reference. Background Art

[0003] Patent Document 1 discloses a backlight unit including a wavelength conversion sheet for converting the wavelength of light emitted by a blue light emitting element, the blue light emitting element, and light reflecting partition walls.

[0004] However, there is no description of the reflective material used for the reflective partition walls, and the structure of the reflective partition walls is unclear. Therefore, the method for forming the reflective partition walls is unclear, making it difficult for a third party to replicate the technology described in Patent Document 1.

[0005] Patent Document 2 discloses a technology such as a color conversion portion including a partition portion having a through hole penetrating a light-transmitting substrate in the thickness direction and a light color conversion substance provided inside the through hole.

[0006] Figure 2 The color filter 10 disclosed in the patent document discloses the composition of the red coloring part 131R, the green coloring part 131G, the blue coloring part 131B and the color conversion part 132. As can be seen from the figure, in the black matrix part 12, the thickness including the height of the red coloring part 121R and the color conversion part 132 is T2, which is recorded as about 10μm in paragraph 0017. The specific method for forming the light-shielding part 122 with thickness containing a light-shielding black pigment such as carbon black is not clear. Although the optical density of the light-shielding part 122 is unclear, in the formation of a 10μm thickness in the black matrix before and after the usual optical density of 4 when suppressing the incident light from entering the adjacent pixels, when using the known photolithography method including the exposure and development process, the exposure light is difficult to penetrate in the thickness direction. Therefore, it is difficult to form a black matrix with thickness. Patent document 2 does not disclose the technology for forming a light-reflecting film.

[0007] Patent Document 3 discloses a technology of a phosphor substrate including a phosphor layer and reflective partition walls surrounding the phosphor layer, which suppresses the excitation light from entering adjacent pixels where it should enter.

[0008] Paragraphs 0010 to 0013 disclose a partition wall structure in which a light scattering layer and a light absorbing layer formed of a material containing a resin and light scattering particles are stacked. Figure 1The thickness of the light scattering layer described in Patent Document 2 is stated to be approximately 1 μm to 100 μm in paragraph 0077, and the preferred method for manufacturing the light scattering layer in paragraph 0080 is described as photolithography. Patent Document 2 also lacks clarity regarding the optical density. However, when using a photosensitive light scattering material with an optical density of approximately 4, which is typically required, to form a light scattering layer and partition walls with a thickness of 10 μm or greater, the exposure light has difficulty penetrating the thickness direction using the known photolithography method involving exposure and development steps. Furthermore, the scattering particles diffuse the exposure light, resulting in a pattern larger than the aperture size of the photomask, making it difficult to form a high-resolution pattern.

[0009] Patent Document 4 discloses a backlight unit including: a phosphor substrate for converting the wavelength of light emitted from an ultraviolet light-emitting element and a blue light-emitting element; the blue light-emitting element; and light-reflecting partition walls.

[0010] While it's unclear whether the metal film is caused by light absorption or reflection, paragraphs 0018, 0021, and 0022 disclose aluminum or aluminum alloys as the metal film. Paragraph 0021 discloses laser ablation for patterning the metal film (removing the bottom of the opening), but does not mention any anticipated damage to the wiring board or LEDs, such as the effects of high heat from laser irradiation or contamination from aluminum scattering. Paragraph 0022 discloses a method for stripping the metal film, but does not describe details of the resist coating, exposure, and development techniques used for stripping that take into account the height (concavity) of the partition walls.

[0011] Prior art literature

[0012] Patent Literature

[0013] Patent Document 1: International Publication No. 2017 / 191714

[0014] Patent Document 2: Japanese Patent Application Laid-Open No. 2018-189920

[0015] Patent Document 3: Japanese Patent Application Laid-Open No. 2015-064391

[0016] Patent Document 4: International Publication No. 2019 / 026826 Summary of the Invention

[0017] Technical problem to be solved by the invention

[0018] The present invention relates to a black matrix substrate and a display device using the black matrix substrate that can provide a bright display device in which the contrast reduction or color purity reduction caused by the light from the light-emitting elements in LED displays such as Mirco LED or Mini LED, and further in organic EL displays, entering adjacent pixels as stray light is alleviated.

[0019] Means for solving technical problems

[0020] A first aspect of the present invention is a black matrix substrate comprising:

[0021] Transparent substrate;

[0022] A black matrix is ​​formed on one surface of the transparent substrate in a first lattice pattern with a line width Ax in the first direction and a line width Ay in the second direction in a plan view;

[0023] a first transparent resin layer covering the black matrix;

[0024] In a plan view from a direction facing one surface of the transparent substrate, on the first transparent resin layer, resin walls are stacked in a second lattice pattern with a line width Dx smaller than the line width Ax and with the same central axis as the line width Ax in the first direction, and with a line width Dy smaller than the line width Ay and with the same central axis as the line width Ay in the second direction; and

[0025] In a plan view facing one surface of the transparent substrate, a light reflecting layer is laminated so as to cover the resin wall, with a line width Cx greater than a line width Dx and having the same central axis as the line width Ax in the first direction, and with a line width Cy greater than a line width Dy and having the same central axis as the line width Ay in the second direction.

[0026] The light reflecting layer has edges (brim) with a width Ex symmetrically provided on the inner side of the line width Ax and from the central axis of the line width Ax along the first direction, and has edges (brim) with a width Ey symmetrically provided on the inner side of the line width Ay and from the central axis of the line width Ay along the second direction,

[0027] Furthermore, a transparent protective layer is provided, which is stacked in a manner covering the light reflecting layer, with a line width Bx including a line width Cx and two edges having the width Ex in the first direction, and a line width By including a line width Cy and two edges having the width Ey in the second direction, when viewed from above in the direction of one surface facing the transparent substrate.

[0028] According to a second aspect of the present invention, in the black matrix substrate of the first aspect, the line width Bx may be smaller than or equal to the line width Ax, and the line width By may be smaller than or equal to the line width Ay.

[0029] According to a third aspect of the present invention, in the black matrix substrate of the first aspect, a color filter including a red filter, a green filter, and a blue filter may be provided between the transparent substrate and the black matrix in a cross-sectional view.

[0030] A fourth aspect of the present invention is the black matrix substrate of the first aspect, wherein a color filter including a red filter, a green filter, and a blue filter may be provided between the black matrix and the first transparent resin layer in a cross-sectional view.

[0031] According to a fifth aspect of the present invention, in the black matrix substrate of the first aspect, the height of the resin wall in a direction away from one surface of the transparent substrate may be set to 2 μm or more and 200 μm or less.

[0032] Here, the aspect ratio or the width of the partition wall varies greatly depending on the pixel pitch or the thickness of the wavelength conversion layer.

[0033] A sixth aspect of the present invention is the black matrix substrate of the first aspect, wherein each region surrounded by the transparent protective layer having the line width Bx and the line width By may include a light wavelength conversion layer.

[0034] A seventh aspect of the present invention is the black matrix substrate of the first aspect, wherein a light scattering layer may be provided in each of the regions surrounded by the transparent protective layer having the line width Bx and the line width By.

[0035] According to an eighth aspect of the present invention, in the black matrix substrate of the first aspect, the light reflecting layer may be a light reflecting layer formed of aluminum or an aluminum alloy.

[0036] A ninth aspect of the present invention is the black matrix substrate according to the first aspect, wherein the light reflecting layer may include silver or a silver alloy sandwiched between the first conductive oxide and the second conductive oxide.

[0037] According to a tenth aspect of the present invention, in the black matrix substrate according to the ninth aspect, the first conductive oxide and the second conductive oxide may contain at least indium oxide and zinc oxide.

[0038] According to an eleventh aspect of the present invention, in the black matrix substrate of the ninth aspect, the first conductive oxide and the second conductive oxide may have different film thicknesses.

[0039] According to a twelfth aspect of the present invention, in the black matrix substrate of the ninth aspect, the first conductive oxide and the second conductive oxide may contain at least indium oxide, and the respective indium oxide contents may be different.

[0040] According to a thirteenth aspect of the present invention, in the black matrix substrate of the first aspect, the first transparent resin layer may contain at least any one of a yellow pigment, an ultraviolet absorber, and transparent fine particles.

[0041] A fourteenth aspect of the present invention is a display device including the black matrix substrate according to any one of the first to thirteenth aspects.

[0042] A fifteenth aspect of the present invention is a method for manufacturing a black matrix substrate used in a display device, comprising at least the following steps (1) to (7).

[0043] (1) A process of forming a black matrix on one surface of a transparent substrate;

[0044] (2) forming a first transparent resin layer on the black matrix;

[0045] (3) forming a resin wall on the first transparent resin layer;

[0046] (4) forming a metal thin film so as to cover the resin wall and the first transparent resin layer;

[0047] (5) forming a photosensitive protective film so as to cover the metal thin film;

[0048] (6) exposing, developing, and hardening the photosensitive protective film to form a transparent protective layer so that a portion of the metal thin film is exposed; and

[0049] (7) A step of removing a portion of the metal thin film by wet etching using the transparent protective layer as a mask to form a light reflecting layer, thereby forming a light reflecting partition wall composed of the resin wall, the light reflecting layer, and the transparent protective layer.

[0050] A sixteenth aspect of the present invention is the method for manufacturing a black matrix substrate according to the fifteenth aspect, which may further include the step of forming a red filter, a green filter, and a blue filter layer.

[0051] Effects of the Invention

[0052] The present invention can provide a bright display device that improves visibility and light utilization efficiency by alleviating the contrast reduction or color purity reduction caused by light from light-emitting elements in LED displays such as Mirco LED or Mini LED, and further in organic EL displays, entering adjacent pixels as stray light. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 FIG. 1 is a partial cross-sectional view of a black matrix substrate according to a first embodiment of the present invention.

[0054] Figure 2 for Figure 1 The enlarged view of section A is shown along Figure 3 Cross-sectional view of line BB'.

[0055] Figure 3 This is a partial top view of the black matrix substrate of the first embodiment of the present invention, Figure 2 A top view observed from the D direction (one surface of the transparent substrate 110).

[0056] Figure 4 This is a partial cross-sectional view of a black matrix substrate according to Modification 3 of the first embodiment of the present invention.

[0057] Figure 5 for Figure 4 A partial enlarged view of section C is shown.

[0058] Figure 6 This is a partial cross-sectional view of a black matrix substrate according to Modification 1 of the first embodiment of the present invention.

[0059] Figure 7 This is a partial cross-sectional view of a black matrix substrate according to Modification 2 of the first embodiment of the present invention.

[0060] Figure 8 It is a partial cross-sectional view of a display device according to a second embodiment of the present invention.

[0061] Figure 9 This is a partial cross-sectional view of a display device according to Modification 1 of the second embodiment of the present invention.

[0062] Figure 10 This is a partial cross-sectional view of a display device according to Modification 2 of the second embodiment of the present invention.

[0063] Figure 11 This is a cross-sectional view showing the state of the black matrix substrate of the present invention in the initial step, and showing a transparent substrate having a black film formed on the entire surface of one surface.

[0064] Figure 12 This is a cross-sectional view showing the configuration of the black matrix substrate of the present invention in one process step, and showing a black matrix formed by patterning the black film.

[0065] Figure 13 The black matrix substrate of the present invention is shown in one process step, and is a cross-sectional view of the black matrix after a first transparent resin layer is formed on the black matrix.

[0066] Figure 14This is a partial cross-sectional view showing a configuration in one process of the black matrix substrate of the present invention, in which a photosensitive resin film is formed on a first transparent resin layer.

[0067] Figure 15 This is a partial cross-sectional view showing the configuration of the black matrix substrate of the present invention in one process step and the resin wall on which the photosensitive resin film is pattern-formed.

[0068] Figure 16 This is a partial cross-sectional view showing a configuration in one process of producing the black matrix substrate of the present invention, in which a metal thin film is formed so as to cover the first transparent resin layer and the resin walls.

[0069] Figure 17 This is a partial cross-sectional view showing a configuration in one process of the black matrix substrate of the present invention, in which a photosensitive protective film is formed on a metal thin film.

[0070] Figure 18 This is a partial cross-sectional view showing the state of the black matrix substrate of the present invention in one process step, showing a configuration in which a photosensitive protective film is patterned as a transparent protective layer.

[0071] Figure 19 This is a cross-sectional view showing the final step of the black matrix substrate of the present invention, in which the metal thin film located between the patterns of the transparent protective layer is removed and a pattern serving as a reflective layer is formed. DETAILED DESCRIPTION

[0072] Below, with reference to the attached Figure 1 Embodiments of the present invention will be described.

[0073] In the following description, identical or substantially identical functions and components are designated by identical reference numerals, and their descriptions are omitted or simplified, or are described only when necessary. Furthermore, as necessary, elements that are difficult to illustrate, such as the configuration of thin-film transistors, the structure of multiple layers constituting a conductive layer, wiring connections to a circuit portion, or switching elements (transistors), may be omitted from illustration or partially omitted.

[0074] In each embodiment described below, characteristic portions are described, and description of components used in a typical display device and portions that are the same as those of the display device of this embodiment will be omitted.

[0075] The ordinal numbers such as "first" or "second" in the first substrate or the second substrate, the first transparent resin layer, the second transparent resin layer, the third transparent resin layer, etc. are used to avoid confusion among the constituent elements and do not limit the quantity. In addition, the matrix configuration of the light-emitting element refers to a configuration in which the light-emitting units containing one or more light-emitting elements are arranged in a matrix shape at a certain pitch when viewed from above. In the following description, the matrix configuration of the light-emitting elements is sometimes referred to as an optical component. When the display device is manufactured, the light-emitting unit is surrounded by a black matrix with a grid-like (first grid-like) pattern when viewed from above. When viewed from above, the light-emitting units surrounded by the black matrix each contain one or more light-emitting elements that are light-emitting diodes. In the display device using regional dimming technology described later, a unit or a plurality of light-emitting units containing, for example, one or more light-emitting elements can be used to adjust the switch of the drive and the brightness of the light. In addition, according to the regional dimming technology, when viewed from above, the number of light-emitting elements and the number of pixels contained in the light-emitting unit can be made larger. In other words, the efficient display device drive brought about by fewer pixels and fewer light-emitting elements can also be said to be an advantage of regional dimming.

[0076] In addition, the term "viewed from above" in the specification may refer to "viewed from above" when observing from one surface of the transparent substrate, or "viewed from above" when observing from a second surface of the transparent substrate (the surface opposite to the one surface) in the normal direction. The former "viewed from above" may be described as "viewed from above" when observing from the observer's direction.

[0077] In the present invention, the black matrix, resin wall, light-reflecting layer, and transparent protective layer overlap about a common center line, each being line-symmetrical in the width direction. This center line is referred to as the "central axis." In the diagram, the central axis is indicated by a dot-dashed line.

[0078] (First embodiment)

[0079] The following uses Figures 1 to 3 The black matrix substrate of the present invention will be described.

[0080] Figure 1 is a partial cross-sectional view of the black matrix substrate 100 of the present invention. Figure 2 for Figure 1 Magnified view of part A. Figure 3 The light reflecting partition wall 6 is observed from one side of the transparent substrate 110 (direction D where the light reflecting partition wall 6 is viewed). Figure 2 In addition, Figures 1 to 3 In the embodiment, the first direction is the X direction, and the second direction is the Y direction. The Z direction can be said to be the height (thickness) direction of the light reflecting partition walls 6 .

[0081] The black matrix substrate 100 is as follows Figure 1As shown, the structure includes a transparent substrate 110 , a black matrix 1 formed on the transparent substrate 110 , a first transparent resin layer 2 , and light-reflective partition walls 6 on the first transparent resin layer 2 .

[0082] Light reflective partition wall 6 Figure 2 、 Figure 3 As shown, it is composed of a resin wall 3, a light reflecting layer 4 and a transparent protective layer 5. The resin wall 3 has a line width Dx in a first direction (X direction in the figure) and a line width Dy in a second direction (Y direction in the figure).

[0083] The light reflecting layer 4 is formed on the resin wall 3 and has a line width Cx in the first direction (X direction in the figure) and a line width Cy in the second direction (Y direction) including the line width Dx of the resin wall 3 .

[0084] The transparent protective layer 5 is formed to cover the light reflecting layer 4 and has a line width Bx in the first direction (X direction) and a line width By in the second direction (Y direction) including the line width Cx of the light reflecting layer 4 .

[0085] The black matrix 1 also has a line width Ax in the first direction (X direction) and a line width Ay in the second direction (Y direction). The line width Bx can be smaller than or equal to the line width Ax. The line width By can be smaller than or equal to the line width Ay.

[0086] The black matrix 1, the transparent protective layer 5, the light reflecting layer 4, and the resin wall 3 all share a central axis 12 as shown in the figure, and their respective grid patterns are as shown in FIG. Figure 3 As can be understood from the figure, the line width of the black matrix 1 is the largest, and decreases in the order of the black matrix 1, the transparent protective layer 5, the light reflecting layer 4, and the resin wall 3.

[0087] The light reflecting layer 4 has brims 4a with a line width Ex on both sides symmetrically from the central axis 12 in the first direction, and has brims 4a with a line width Ey on both sides symmetrically from the central axis in the second direction.

[0088] The above relationship of line width can be summarized as follows.

[0089] Ax≥Bx>Cx>Dx (1)

[0090] Bx≥Cx+2Ex (2)

[0091] Ay≥By>Cy>Dy (3)

[0092] By≥Cy+2Ey (4)

[0093] (Method for Manufacturing Black Matrix Substrate of the Present Invention)

[0094] The following uses Figures 11 to 19 A method for forming the black matrix 1 , the transparent protective layer 5 , the light reflecting layer 4 , and the resin wall 3 will be described. Figures 11 to 19 It is a partial cross-sectional view showing the intermediate structure in each process of the black matrix substrate of the present invention.

[0095] Figure 11 The black film 7 is formed by coating a black photosensitive resist (for example, an alkali-soluble negative resist) on the transparent substrate 110 .

[0096] The black film 7 is exposed, developed, and hardened using a known photolithography technique to form a Figure 12 The black matrix 1 shown. At this time, it is sufficient if the optical density of the black matrix 1 is in the range of 1 to 3. The optical density can also be 1 or less. The reason is that, as shown in the subsequent process, since the light reflecting layer 4 is formed of an alloy of aluminum, silver or other elements containing high light-shielding properties in the direction of its film thickness, the black matrix 1 can be formed with a low optical density. In other words, by utilizing the light-shielding properties of the light reflecting layer 4 arranged at the bottom of the black matrix when viewed from above, the film thickness of the black matrix 1 can be, for example, a thin film of 0.3 μm or more and 1.0 μm or less, or less than 1.5 μm. When the film thickness of the black matrix 1 is 1.5 μm or more, uneven film thickness will be formed on the first transparent resin layer 2 formed in the next process, resulting in uneven height or shape of the light-reflective partition wall 6, which is not preferred. When it is less than 0.3 μm, the reflected light (reflected light of external incident light) from the light reflecting layer serving as the base of the black matrix 1 will leak out, which will easily reduce the display quality.

[0097] The above-described process of forming the black film 7 by applying a black photosensitive resist and forming the black matrix 1 using a known photolithography technique is referred to as a "black matrix forming process."

[0098] Figure 13 The structure in which the first transparent resin layer 2 is laminated so as to cover the black matrix 1 is shown.

[0099] Figure 14 The structure in which a photosensitive resin film 8 is further laminated on the first transparent resin layer 2 is shown. The photosensitive resin film 8 is exposed, developed, and hardened using a known photolithography technique to obtain Figure 15 The resin wall 3 is shown.

[0100] A transparent negative resist or positive resist that does not contain a coloring pigment such as a white pigment or a black pigment can be applied to the photosensitive resin film 8 .

[0101] The height (film thickness) of the resin wall 3 can be, for example, not less than 2 μm and not more than 200 μm. In addition, the height of the resin wall 3 as the height of the light-reflective partition wall 6 can be not less than 2 μm and not more than 200 μm. In addition, when the black matrix substrate 100 of the present invention is used as a display device, the height of the light-emitting element such as the LED chip can be added to make the height of the light-reflective partition wall 6 greater than 200 μm. The height of the light-reflective partition wall 6 will be described in detail in the embodiment of the display device later. In addition, Figures 14 and 15 The steps from laminating the photosensitive resin film 8 to forming the resin wall 3 using a known photolithography technique are referred to as “a step of forming the resin wall 3 ”.

[0102] Then, if Figure 16 As shown, a light-reflective metal film 9 is formed to cover the resin wall 3 and the first transparent resin layer 2 by vacuum film forming techniques such as vacuum evaporation or sputtering. The metal film 9 can be made of light-reflective thin films such as aluminum, aluminum alloy, silver, and silver alloy. The metal film 9 is patterned as the light-reflecting layer 4 in a subsequent step. The film thickness of the aluminum, aluminum alloy, silver, and silver alloy film can be, for example, 0.1 μm to 0.3 μm. A film thickness of 0.1 μm or more can achieve sufficient reflection of visible light and light-shielding properties with an optical density of 4 or more. From the perspective of light reflectivity, even with a film thickness of 0.1 μm or more, it is difficult to achieve an increase in reflectivity. The film thickness of the metal film 9 deposited on the side of the resin wall 3 tends to be thinner than the film thickness deposited on the top of the resin wall 3 shown in the figure. It is preferred that the film thickness of the metal film 9 deposited on the side of the resin wall 3 be at least 0.1 μm.

[0103] like Figure 17 As shown, a photosensitive protective film 10 is applied to cover the metal thin film 9 and the resin wall 3. The photosensitive protective film 10 is exposed, developed, and hardened using a known photolithography technique to form a Figure 18 The transparent protective layer 5 is shown. As the photosensitive protective film 10, a transparent negative resist or positive resist that does not contain a coloring pigment such as a white pigment or a black pigment can be applied. Figure 17 The photosensitive protective film 10 that is removed by development is represented by the development removal portion Dv. In the development removal portion Dv, the metal thin film 9 of the base is exposed to the surface, forming an exposed portion Et (see Figure 18 ).

[0104] Next, the transparent protective layer 5 is left as a mask for wet etching, and the metal thin film 9 is wet-etched to remove the exposed portion Et of the metal thin film. Figure 19 The light reflecting layer 4 is shown. Figure 19 In the process shown, the exposed portion Et is removed by a simple wet etching method without heat damage, thereby ensuring that the pixel opening portion 11 (see FIG. Figure 4 ), forming the black matrix substrate 100 with light-reflective partition walls of the present invention.

[0105] The etchant used in wet etching may be a nitric acid-acetic acid etching solution, an etching solution containing ferric chloride, an etching solution containing cesium ammonium nitrate, ammonium fluoride, an oxidizing agent such as an organic sulfonic acid, or an alkaline etching solution such as sodium hydroxide or potassium hydroxide.

[0106] In the above manufacturing method, a process of forming a red filter, a green filter, and a blue filter may be added between the process of forming a black matrix and the process of forming a first transparent resin layer on the black matrix. Figure 6 The color filter 50 described in the present invention is a method for manufacturing a black matrix substrate including light-reflective partition walls.

[0107] Alternatively, the following steps may be performed to form a red filter, a green filter, and a blue filter on the transparent substrate before forming the black matrix. Figure 7 The color filter 50 described in the present invention is a method for manufacturing a black matrix substrate including light-reflective partition walls.

[0108] (Variation 1 of the First Embodiment)

[0109] Figure 6 The present invention is a partial cross-sectional view of a black matrix substrate 100A in which a color filter 50 including a red filter R, a green filter G, and a blue filter B is inserted between a black matrix 1 and a first transparent resin layer 2. The order of the colors of the red filter R, green filter G, and blue filter B is not limited.

[0110] As described later, a wavelength conversion layer or a light scattering layer, or further a mixed layer of a wavelength conversion material and a light scattering material may be provided in the region Bw surrounded by the light reflective partition walls.

[0111] (Variation 2 of the First Embodiment)

[0112] Figure 7 The present invention is a partial cross-sectional view of a black matrix substrate 100B in which a color filter 50 including a red filter R, a green filter G, and a blue filter B is inserted between a transparent substrate 110 and a black matrix 1. The order of the colors of the red filter R, green filter G, and blue filter B is not limited. Because the color filters are formed on a flat transparent substrate rather than on a black matrix having uneven surfaces before forming the red filter R, green filter G, and blue filter B, the color filters of Modification 2 have improved flatness.

[0113] As described later, a wavelength conversion layer or a light scattering layer, or further a mixed layer of a wavelength conversion material and a light scattering material may be provided in the region Bw surrounded by the light reflective partition walls.

[0114] As described above, in the present invention, a color filter including a red filter R, a green filter G, and a blue filter B may be inserted between the black matrix 1 and the first transparent resin layer 2 , or between the transparent substrate 110 and the black matrix 1 .

[0115] Coloring materials that can be used in black matrices include organic pigments and inorganic pigments. Examples of organic pigments include carbon black, graphite, aniline black, and cyanine black. Inorganic pigments include titanium oxide, titanium nitride, and iron oxide. These pigments can be used alone or in combination to achieve the desired light-blocking properties. Carbon black is particularly preferred as a light-blocking material.

[0116] Examples of red organic pigments that can be used in the red filter R include CI Pigment Red 7, 14, 41, 48:2, 48:3, 48:4, 81:1, 81:2, 81:3, 81:4, 146, 168, 177, 178, 179, 184, 185, 187, 200, 202, 208, 210, 246, 254, 255, 264, 270, 272, and 279. A yellow pigment or an orange pigment can also be used in the red filter R.

[0117] Examples of yellow organic pigments that can be used in the present invention include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 111 3, 114, 115, 116, 117, 118, 119, 120, 123, 126, 127, 128, 129, 147, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 187, 188, 193, 194, 199, 198, 213, 214, etc.

[0118] Green pigments that can be used for the green filter G include CI Pigment Green 7, 10, 36, and 37, and can also be used in combination with yellow pigments. Preferably, zinc phthalocyanine green pigments or aluminum phthalocyanine green pigments can be used.

[0119] Blue pigments that can be used in the blue filter B include CI Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 22, 60, and 64. Violet pigments can also be used in combination. Examples of the violet pigment include CI Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, and 50.

[0120] These pigments are dispersed in a transparent resin along with an organic solvent or dispersant. The transparent resin preferably has a transmittance of 90% or greater in the visible light region, preferably an alkali-soluble photosensitive resin containing a resin precursor. The pigments may be contained in an amount ranging from 15% to 65% by weight relative to the resin.

[0121] Examples of photosensitive resins include polyimide resins, epoxy resins, acrylic resins, melamine resins, phenolic resins, oxetane resins, siloxane resins, and benzoxazine resins, which are obtained by reacting a (meth)acrylic compound or cinnamic acid having a reactive substituent such as an isocyanate group, an aldehyde group, an epoxy group, or a silanol group with a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, or an amino group to introduce a photocrosslinkable group such as a (meth)acryloyl group or a styryl group into the linear polymer. When curing is performed by irradiation with ultraviolet light having a wavelength of, for example, 365 nm, a photopolymerization initiator or the like may be further added.

[0122] (Variation 3 of the First Embodiment)

[0123] use Figure 4 and Figure 5 Modification 3 of the black matrix substrate of the present invention will be described.

[0124] Figure 4 FIG. 1 is a partial cross-sectional view of a black matrix substrate 100C according to the present invention. Figure 5 for Figure 4 Partially enlarged view of section C.

[0125] Silver has a light reflectivity that is approximately 10% higher than aluminum within the wavelength range of 420nm to 700nm. Therefore, using silver or a silver alloy as a light-reflecting layer allows for more efficient use of light from light-emitting elements such as LEDs, which will be described later.

[0126] However, silver has low adhesion to resin or glass substrates, and from this point of view, it is difficult to provide a light-reflecting layer at a practical level.

[0127] Figure 5 This figure shows a light-reflecting layer 4 of silver or a silver alloy sandwiched between a first conductive oxide 41A and a second conductive oxide 41B. Indium oxide, zinc oxide, tin oxide, or a composite oxide containing these is conductive and enhances the adhesion of silver (or a silver alloy) to a resin or glass substrate. By adjusting the amount of indium oxide and zinc oxide added, the etching rate with silver (or a silver alloy) can be adjusted, enabling wet etching of the light-reflecting layer 4 of silver or a silver alloy sandwiched between conductive oxides 41A and 41B. Indium oxide, zinc oxide, tin oxide, or a composite oxide containing these has high transmittance in the visible light region.

[0128] This modification example 3 proposes the use of silver (or silver alloy) having high light reflectivity.

[0129] As described above, the light-reflecting layer 4 in this third modification is composed of silver or a silver alloy sandwiched between conductive oxides. The thickness of the silver or silver alloy, measured as the thickness t2 of the metal thin film deposited on the side of the resin wall, can be, for example, 0.1 μm to 0.3 μm. The thickness t1 of the metal thin film deposited on the top of the resin wall tends to be thicker than the thickness t2 of the metal thin film deposited on the side. The thicknesses t3 and t4 of the first and second conductive oxides 41A, 41B can be, for example, 0.01 μm to 0.05 μm.

[0130] As described later, a wavelength conversion layer or a light scattering layer may be provided in the region Bw surrounded by the light-reflective partition walls.

[0131] (Second Embodiment, Display Device A)

[0132] Figure 8 The display device according to the present invention is a partial cross-sectional view of a display device 200 using the black matrix substrate 100 of Embodiment 1. A light scattering layer 30 is provided between the light reflective partition walls 6 and in a region Bw surrounded by the light reflective partition walls.

[0133] Figure 8 The optical module 20a shown has light emitting elements as LEDs on the optical module substrate 120, and each light emitting element is driven by a thin film transistor (not shown). Figure 8 In the configuration of the display device 200 shown, the light emitting elements may be arranged in the respective openings as red light emitting elements 21, green light emitting elements 22, and blue light emitting elements 23. Alternatively, these light emitting elements may be white light emitting elements.

[0134] As a material for a substrate that can be applied to the transparent substrate 110 or the optical component substrate 120, a transparent substrate such as a glass substrate, a quartz substrate, a sapphire substrate, or a plastic substrate can be used. It is preferred that the substrate materials constituting the transparent substrate 110 and the optical component substrate 120 have the same thermal expansion coefficient. When different substrate materials are used for the optical component substrate (array substrate) 120 and the transparent substrate 110, there is a risk of problems such as warping or peeling of the substrate from the perspective of thermal expansion coefficient. In addition, an array substrate refers to a substrate on which thin film transistors for driving display functional layers such as light-emitting elements or liquid crystal layers are arranged in a matrix. At this time, one or more thin film transistors are arranged in one pixel, which is the minimum display unit. The liquid crystal layer is usually driven by one thin film transistor in one pixel, and sometimes seven thin film transistors are arranged in one pixel in light-emitting elements such as organic EL.

[0135] The height H1 of the light-reflective partition walls 6 includes the thickness H30 of the light-scattering layer and the height H2 of the light-emitting elements 21, 22, and 23. When the height H2 of the light-emitting elements 21, 22, and 23 increases, it is preferable to add the height H2 so that the height H1 of the light-reflective partition walls 6 is greater than the height H2 of the light-emitting elements 21, 22, and 23. For example, the height H1 of the light-reflective partition walls 6 can be within a range of 2 μm to 200 μm. Although the details of the light-emitting element structure are omitted in the figure, they include, for example, an upper electrode, an n-type semiconductor layer, a light-emitting layer, a p-type semiconductor layer, a lower electrode, a low-melting-point alloy layer for flip-chip mounting, and a reflective electrode. The semiconductor layer including the light-emitting layer of the light-emitting element can be formed of any semiconductor, such as GaN, AlGaN, InGaN, InAlN, AlInGaN, ZnSe, GaP, AlGaP, AlGaAs, or AlInGaP, or a stack of these.

[0136] When the wavelength conversion layer is filled in the light reflective partition walls, the height H1 of the light reflective partition walls is required to be the same as or greater than the thickness of the wavelength conversion layer, and may be, for example, within a range of 2 μm to 200 μm.

[0137] The height H1 of the light-absorbing partition wall may be greater than 200 μm. However, when using a general coating apparatus such as a curtain coater or a slit coater, it is difficult to form a coating film having a thickness after drying, so 200 μm is an appropriate upper limit.

[0138] In an embodiment of the present invention, the "display function layer" possessed by the display device can use any one of a plurality of light emitting diode elements called LEDs (Light Emitting Diodes), a plurality of organic EL (organic electroluminescent) elements also called OLEDs (Organic Light Emitting Diodes), or a liquid crystal layer.

[0139] Among LED chips used as light-emitting elements, vertical LED chips, whose electrodes (n-side and p-side electrodes) are divided vertically along their thickness, are preferred for high-definition applications. Horizontal LED chips, mounted using wire bonding, can also be used in large-scale display devices such as TVs. Furthermore, flip-chip mounting of light-emitting elements can be replaced with mounting using anisotropic conductive film.

[0140] LEDs are generally manufactured by epitaxially growing them on sapphire or silicon substrates with a buffer layer interposed therebetween using methods such as MOCVD. LEDs can be separated from these sapphire or silicon substrates using laser ablation to create LED chips.

[0141] Optically isotropic transparent microparticles and metal oxide particles can be used in the light scattering particles 30a. For example, light scattering particles having an average particle size of 0.03 μm or more and 5.0 μm or less are preferably used in the light scattering layer. These particles having an average particle size of 0.03 μm or more and 5.0 μm or less can be applied to the light scattering layer described later.

[0142] The "optical isotropy" of optically isotropic transparent particles means that the transparent particles used in the embodiments of the present invention have a crystalline structure in which the a-axis, b-axis, and c-axis are respectively equal, or are amorphous, and the propagation of light is isotropic without being affected by the crystalline axes or crystalline structure. Silica particles have an amorphous structure (amorphous). Particles of resins such as resin beads are known to have various properties including refractive index, and these particles can be combined. Particles of resins such as acrylic acid, styrene, urethane, nylon, melamine, and benzoguanamine can also be used in combination.

[0143] The metal oxide is an oxide containing one metal selected from the group consisting of Li, Be, B, Na, Mg, Al, Si, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Mo, Cs, Ba, La, Hf, W, Tl, Pb, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Sb, Sn, Zr, Nb, Ce, Ta, In, and combinations thereof. Specifically, it can be one selected from the group consisting of Al2O3, SiO2, ZnO, ZrO2, BaTiO3, TiO2, Ta2O5, Ti3O5, ITO, IZO, ATO, ZnO-Al, Nb2O3, SnO, MgO, and combinations thereof. If necessary, a material surface-treated with a compound having an unsaturated bond, such as an acrylate, can also be used.

[0144] These phosphors, quantum dots, or light-scattering particles are dispersed in a transparent resin along with an organic solvent or dispersant for use. The transparent resin preferably has a transmittance of 90% or greater in the visible light region, and is preferably an alkali-soluble photosensitive resin containing a resin precursor. The phosphors, quantum dots, or light-scattering particles can be contained in an amount ranging from 15% to 65% by mass relative to the resin.

[0145] Examples of photosensitive resins include polyimide resins, epoxy resins, acrylic resins, melamine resins, phenolic resins, oxetane resins, siloxane resins, and benzoxazine resins, which are obtained by reacting a (meth)acrylic compound or cinnamic acid having a reactive substituent such as an isocyanate group, an aldehyde group, an epoxy group, or a silanol group with a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, or an amino group to introduce a photocrosslinkable group such as a (meth)acryloyl group or a styryl group into the linear polymer. When curing is performed by irradiation with ultraviolet light having a wavelength of, for example, 365 nm, a photopolymerization initiator or the like may be further added.

[0146] (Second Embodiment, Display Device B)

[0147] Figure 9 The display device according to the present invention is a partial cross-sectional view of a display device 300 employing the black matrix substrate 100A of the first embodiment and modification 1. Wavelength conversion layers 31, 32, and 33 are disposed in a region Bw surrounded by light-reflective partition walls 6. A red inorganic phosphor 31r can be used for the wavelength conversion layer 31, a green inorganic phosphor 32g can be used for the wavelength conversion layer 32, and a blue inorganic phosphor 33b can be used for the wavelength conversion layer 33.

[0148] Optical module 20b includes LED light emitting elements 24 on optical module substrate 120. Each light emitting element is driven by a thin film transistor (not shown). Light emitting element 24 is, for example, a near-ultraviolet light emitting element emitting light with a wavelength in the range of 300nm to 400nm and is disposed in each opening.

[0149] The height H3 of the light-reflective partition wall 6 includes the thickness H4 of the wavelength conversion layer and the height H5 of the light-emitting element 24. It is preferably equal to or greater than the sum of H4 and H5. The height H3 of the light-reflective partition wall 6 can be, for example, within a range of 2 μm to 200 μm.

[0150] Quantum dots or organic fluorescent pigments can also be used in the wavelength conversion layers 31, 32, and 33. However, the decomposition and luminescence characteristics caused by the excitation light or heat emitted by the LED are significantly degraded, so it is preferred to use an inorganic phosphor with high heat resistance and light resistance. In addition, when the particle shape of the inorganic phosphor particles used in the wavelength conversion layer is in the range of 1.0 μm or more and 10.0 μm or less, the wavelength conversion efficiency or the dispersibility in the coating film is good. The wavelength conversion layer can also use quantum dot materials, or they can be used in combination. The thickness of the wavelength conversion layer is obtained by fully absorbing and converting the excitation light emitted by the light source by the inorganic phosphor or quantum dot material, and its thickness can be, for example, in the range of 2 μm to 200 μm.

[0151] As the red inorganic phosphor 31r, Y2O2S:Eu can be cited. 3+ 、YAlO3:Eu 3+ 、Ca2Y2(SiO4)6:Eu 3+ 、LiY9(SiO4)6O2:Eu 3+ 、YVO4:Eu 3+ 、CaS:Eu 3+ 、Gd2O3:Eu 3+ 、Gd2O2S:Eu 3+ 、Y(P,V)O4:Eu 3+ 、Mg4GeO 5.5 F:Mn 4 + 、Mg4GeO6:Mn 4+ 、K5Eu 2.5 (WO4) 6.25 、Na5Eu 2.5 (WO4) 6.25 、K5Eu 2.5 (MoO4) 6.25 、Na5Eu 2.5 (MoO4) 6.25 wait.

[0152] As the green inorganic phosphor 32g, (BaMg)Al 10 O 17 :Eu 2+ ,Mn 2+ 、Sr4Al 14 O 25 :Eu 2+ 、(SrBa)Al 12 Si2O8:Eu 2+ 、(BaMg)2SiO4:Eu 2+ 、Y2SiO5:Ce 3+ 、Sr2P2O7-Sr2B2O5:Eu 3+、(BaCaMg)5(PO4)3Cl:Eu 2 + 、Sr2Si3O8-2SrCl2:Eu 2+ 、Zr2SiO4、MgAl 11 O 19 :Ce 3+ ,Tb 3+ 、Ba2SiO4:Eu 2+ 、Sr2SiO4:Eu 2+ 、(BaSr)SiO4:Eu 2+ wait.

[0153] As the blue inorganic phosphor 33b, Sr2P2O7:Sn 4+ 、Sr4Al 14 O 25 :Eu 2+ 、BaMgAl 10 O 17 :Eu 2+ 、SrGa2S4:Ce 3+ 、CaGa2S4:Ce 3+ 、(Ba、Sr)(Mg、Mn)Al 10 O 17 :Eu 2+ 、(Sr、Ca、Ba2、Mg) 10 (PO4)6Cl2:Eu 2+ 、BaAl2SiO8:Eu 2+ 、Sr2P2O7:Eu 2+ 、Sr5(PO4)3Cl:Eu 2+ 、(Sr,Ca,Ba)5(PO4)3Cl:Eu 2+ 、BaMg2Al 16 O 27 :Eu 2+ 、(Ba,Ca)5(PO4)3Cl:Eu 2+ 、Ba3MgSi2O8:Eu 2+ 、Sr3MgSi2O8:Eu 2+ wait.

[0154] (Second Embodiment, Display Device C)

[0155] Figure 10The display device according to the present invention is a partial cross-sectional view of a display device 400 employing the black matrix substrate 100A of the first embodiment and modification 1. Wavelength conversion layers 31 and 32 and a light scattering layer 30 are disposed in a region Bw surrounded by light-reflective partition walls 6. A red inorganic phosphor 31r can be used for the wavelength conversion layer 31, a green inorganic phosphor 32g can be used for the wavelength conversion layer 32, and light scattering particles 30a can be used for the light scattering layer 30.

[0156] The optical module 20c includes light emitting elements 23, which are LEDs, on the optical module substrate 120. Each light emitting element is driven by a thin film transistor (not shown). The light emitting element 23 is, for example, a blue light emitting element emitting light with a wavelength in the range of 400 nm to 500 nm and is disposed in each opening.

[0157] The height H6 of the light-reflective partition walls 6 includes the thickness H7 of the wavelength conversion layers 31 and 32 and the light-scattering layer 30, as well as the height H8 of the light-emitting element 23. The height H6 is preferably equal to or greater than the sum of H7 and H8. The height H3 of the light-reflective partition walls 6 can be, for example, within a range of 2 μm to 200 μm.

[0158] The display device with the black matrix substrate of the above embodiment can be used in various applications. As electronic devices that can be applied to the display device of the above embodiment, mobile phones, portable game devices, mobile information terminals, laptop computers, e-books, video cameras, digital cameras, head-mounted displays, navigation systems, sound players (car audio, digital audio players, etc.), copiers, fax machines, printers, printing compound machines, vending machines, automatic teller machines (ATMs), personal authentication devices, optical communication equipment, IC cards and other electronic devices can be cited. The above embodiments can be used in combination. In the electronic device equipped with the display device of the embodiment of the present invention, it is preferably further equipped with an antenna for communication or contactless power supply.

[0159] While preferred embodiments of the present invention have been described above, it should be understood that these are merely illustrative and should not be construed as limiting the present invention. Additions, omissions, substitutions, and other modifications may be made without departing from the scope of the present invention. Therefore, the present invention should not be construed as limited by the foregoing description but rather as defined by the appended claims.

[0160] Explanation of symbols

[0161] 1 Black Matrix

[0162] 2 First transparent resin layer

[0163] 3 Resin wall

[0164] 4 Light reflection layer

[0165] 4a brim

[0166] 5. Transparent protective layer

[0167] 6 Light-reflective partition

[0168] 7 Black film

[0169] 8 Photosensitive resin film

[0170] 9 metal film

[0171] 10 Photosensitive protective film

[0172] 11 pixel opening

[0173] 12 Center axis

[0174] 20a, 20b, 20c optical components

[0175] 21, 22, 23, 24 Light-emitting elements

[0176] 30 Light scattering layer

[0177] 30a Light-scattering particles

[0178] 31, 32, 33 wavelength conversion layer

[0179] 31r red inorganic phosphor

[0180] 32g green inorganic phosphor

[0181] 33b blue inorganic phosphor

[0182] 41A First Conductive Oxide

[0183] 41B Second conductive oxide

[0184] 50 color filter layers

[0185] 100, 100A, 100B, 100C black matrix substrate

[0186] 110 Transparent substrate

[0187] 120 Optical Component Substrate

[0188] 200, 300, 400 display devices

[0189] Ax, Ay Line width of the black matrix

[0190] Bx, By Line width of transparent protective layer

[0191] Cx, Cy Line width of light reflection layer

[0192] Dx, Dy Line width of resin wall

[0193] Ex, Ey: width of the brim

[0194] R Red filter

[0195] G Green filter

[0196] B Blue filter

[0197] Bw Area surrounded by light-reflective partitions

[0198] t1, t2: thickness of light reflecting layer

[0199] t3, t4 thickness of conductive oxide

[0200] H1, H3, H6 Height of light-reflecting partition

[0201] H2, H5, H8 Height of light emitting element

[0202] H4 Height of wavelength conversion layer

[0203] H7 Height of wavelength conversion layer and light scattering layer

[0204] H30 Height of light scattering layer

Claims

1. A black matrix substrate comprising: Transparent substrate; A black matrix is ​​formed on one surface of the transparent substrate in a first lattice pattern with a line width Ax in the first direction and a line width Ay in the second direction in a plan view; a first transparent resin layer covering the black matrix; In a plan view from a direction facing one surface of the transparent substrate, on the first transparent resin layer, resin walls are stacked in a second lattice pattern, with a line width Dx smaller than the line width Ax and having the same central axis as the line width Ax in the first direction, and with a line width Dy smaller than the line width Ay and having the same central axis as the line width Ay in the second direction; as well as In a plan view facing one surface of the transparent substrate, a light reflecting layer is laminated so as to cover the resin wall, with a line width Cx greater than a line width Dx and having the same central axis as the line width Ax in the first direction, and with a line width Cy greater than a line width Dy and having the same central axis as the line width Ay in the second direction. The light reflecting layer includes edges having a width Ex on the inner side of the line width Ax along the first direction, the edges being symmetrical with respect to the central axis of the line width Ax, and edges having a width Ey on the inner side of the line width Ay along the second direction, the edges being symmetrical with respect to the central axis of the line width Ay. Furthermore, a transparent protective layer is provided, which is stacked in a manner covering the light reflecting layer with a line width Bx in the first direction and a line width By in the second direction when viewed from above in the direction facing one surface of the transparent substrate, wherein the line width Bx includes a line width Cx and the two edges having the width Ex, and the line width By includes a line width Cy and the two edges having the width Ey.

2. The black matrix substrate according to claim 1, wherein The line width Bx is smaller than or equal to the line width Ax, and the line width By is smaller than or equal to the line width Ay.

3. The black matrix substrate according to claim 1, wherein: In cross-sectional view, a color filter including a red filter, a green filter, and a blue filter is provided between the transparent substrate and the black matrix.

4. The black matrix substrate according to claim 1, wherein In cross-sectional view, a color filter including a red filter, a green filter, and a blue filter is provided between the black matrix and the first transparent resin layer.

5. The black matrix substrate according to claim 1, wherein: A height of the resin wall in a direction away from one surface of the transparent substrate is 2 μm or more and 200 μm or less.

6. The black matrix substrate according to claim 1, wherein: A light wavelength conversion layer is provided in each region surrounded by the transparent protective layer having the line width Bx and the line width By.

7. The black matrix substrate according to claim 1, wherein: A light scattering layer is provided in each region surrounded by the transparent protective layer having the line width Bx and the line width By.

8. The black matrix substrate according to claim 1, wherein: The light reflecting layer is a light reflecting layer formed of aluminum or an aluminum alloy.

9. The black matrix substrate according to claim 1, wherein: The light reflecting layer includes silver or a silver alloy sandwiched between a first conductive oxide and a second conductive oxide.

10. The black matrix substrate according to claim 9, wherein: The first conductive oxide and the second conductive oxide contain at least indium oxide and zinc oxide.

11. The black matrix substrate according to claim 9, wherein: The first conductive oxide and the second conductive oxide have different film thicknesses.

12. The black matrix substrate according to claim 9, wherein: The first conductive oxide and the second conductive oxide contain at least indium oxide, and the indium oxide contents of the respective oxides are different.

13. The black matrix substrate according to claim 1, wherein: The first transparent resin layer contains at least one of a yellow pigment, an ultraviolet absorber, and transparent fine particles. 14 . A display device comprising the black matrix substrate according to claim 1 .

15. A method for manufacturing a black matrix substrate for use in a display device, comprising at least the following steps (1) to (7): (1) A process of forming a black matrix on one surface of a transparent substrate; (2) forming a first transparent resin layer on the black matrix; (3) forming a resin wall on the first transparent resin layer; (4) forming a metal thin film so as to cover the resin wall and the first transparent resin layer; (5) forming a photosensitive protective film so as to cover the metal thin film; (6) exposing, developing, and hardening the photosensitive protective film, and forming a transparent protective layer so that a portion of the metal thin film is exposed; as well as (7) A step of removing a portion of the metal thin film by wet etching using the transparent protective layer as a mask to form a light reflecting layer, thereby forming a light reflecting partition wall composed of the resin wall, the light reflecting layer, and the transparent protective layer. 16 . The method for manufacturing a black matrix substrate according to claim 15 , further comprising forming a red filter, a green filter, and a blue filter layer between the step of forming the black matrix and the step of forming the first transparent resin layer on the black matrix.

Images