Display device

Abstract

[Problem] To solve the problem of degradation in design of an LED display device due to insufficient concealment of wiring by peripheral insulating film for wiring insulation, protection film, isolating wall, and the like. [Solution] This display device at least comprises wires, a cured film, and a plurality of light emitting elements. The light emitting elements each have electrodes on different two surfaces thereof. At least one of the electrodes is connected to a plurality of the wires extending within the cured film, and the respective wires are configured to retain the electrical insulating properties by means of the cured film. The cured film is a film obtained by curing a resin composition comprising a resin (A), and has a transmittance of 0.1-95% with respect to light having a wavelength of 450 nm, at the reference thickness of the cured film of 5 μm.

Description

display device

[0001] The present invention relates to a display device such as an LED display.

[0002] In recent years, in order to further improve the performance of displays, LED displays, which are constructed by arranging light-emitting diodes (LEDs) in the same number as the number of pixels, have been attracting attention as a new display technology following liquid crystal displays, plasma displays, and organic electroluminescent (EL) displays. In particular, mini-LED displays, which have reduced the size of the LEDs serving as light sources from the conventional approximately 1 mm to 100-700 μm, and micro-LED displays, which have been miniaturized to less than 100 μm, have been attracting attention and are the subject of active research and development. Key features of mini-LED displays and micro-LED displays include high contrast, fast response, low power consumption, and a wide viewing angle. They are expected to be used not only in traditional wearable displays such as televisions, smartphones, and smartwatches, but also in a wide range of promising new applications such as signage, AR, VR, and even transparent displays capable of displaying spatial images.

[0003] Various configurations have been proposed for LED display devices aimed at practical application and high performance, including a configuration in which micro LEDs are arranged on a multilayer flexible circuit board (see Patent Document 1), a configuration in which a bank layer and trace lines are provided on a display substrate, and micro LEDs and a micro driver chip are arranged on the bank layer and trace lines (see Patent Document 2), and a configuration in which a planarizing film is formed on a growth substrate on which a light emitting element body having electrode pads is integrally formed, the planarizing film on the electrode pads is removed to expose the electrode pads, and outer electrode pads connected to the electrode pads are formed on the planarizing film, and the outer electrode pads are arranged opposite the circuit side electrode portions formed on a circuit board, thereby electrically connecting the front external electrode pads to the circuit side electrode portions (see Patent Document 3).

[0004] JP 2019-153812 A JP 2020-52404 A JP 2020-68313 A

[0005] However, the LED display device described in the above document has a problem in that the wiring is not sufficiently concealed by the surrounding insulating film for insulating wiring, protective film, partition wall, etc., which reduces the design.

[0006] In order to solve the above problems, the present invention has the following configuration.

[0007] [1] A display device having at least wiring, a cured film, and a plurality of light-emitting elements, wherein the light-emitting elements each have an electrode on two different surfaces, at least one of the electrodes is connected to a plurality of wirings extending in the cured film, and the plurality of wirings are configured to maintain electrical insulation by the cured film, the cured film is a film obtained by curing a resin composition containing (A) resin, and the transmittance of light with a wavelength of 450 nm at a standard thickness of 1 μm is 0.1% or more and 95% or less.

[0008] [2] The display device according to [1], wherein the transmittance of light with a wavelength of 450 nm at a standard thickness of 5 μm of the cured film is 0.1% or more and 79% or less.

[0009] [3] The display device according to [1], wherein the transmittance of light having a wavelength of 450 nm at a standard thickness of 1 μm of the cured film is 0.1% or more and 25% or less.

[0010] [4] The display device according to any one of [1] to [3], wherein the cured film has a total thickness of 5 μm or more and 100 μm or less.

[0011] [5] The display device according to any one of [1] to [4], wherein the number of layers of the cured film is 2 to 10.

[0012] [6] The display device according to any one of [1] to [5], wherein the cured film has an opening pattern penetrating through it in the thickness direction, the wiring is arranged at least in the opening pattern, and the longest length of the bottom surface of the wiring formed at a position in contact with the light-emitting element is 2 μm or more and 20 μm or less.

[0013] [7] The display device according to any one of [1] to [6], wherein the cured film covers a surface other than the light extraction surface of the light-emitting element.

[0014] [8] A display device having at least a substrate having wiring and / or TFTs, a cured film, and a plurality of light-emitting elements, wherein the light-emitting elements each have electrodes on two different surfaces, at least a portion of the wiring and / or TFTs is in contact with the cured film, the cured film is a film obtained by curing a resin composition containing (A) resin, and the transmittance of the cured film at a thickness of 1 μm for light with a wavelength of 450 nm is 0.1% or more and 95% or less.

[0015] [9] The display device according to any one of [1] to [8], wherein a partition wall having a thickness equal to or greater than the thickness of the light-emitting element is disposed between the plurality of light-emitting elements.

[0016]

[10] The display device according to any one of [1] to [9], wherein the light-emitting element is an LED having a side length of 5 μm or more and 700 μm or less.

[0017]

[11] The display device according to any one of [1] to

[10] , further comprising a driving element and a substrate, the driving element being connected to the light-emitting element through wiring, and at least a portion of the wiring extending to a side surface of the substrate.

[0018]

[12] The display device according to any one of [1] to

[11] , further comprising a light-shielding layer between the plurality of light-emitting elements.

[0019]

[13] The display device according to any one of [1] to

[12] , wherein the resin (A) contains one or more resins selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, polybenzoxazole precursor, and copolymers thereof.

[0020]

[14] The display device according to any one of [1] to

[13] , wherein the resin composition containing the resin (A) further contains a photosensitizer (B).

[0021]

[15] The display device according to any one of [1] to

[14] , wherein the resin composition containing the resin (A) further contains a colorant (C), and the colorant (C) contains a colorant (C-1) having an absorption maximum in a wavelength range of 400 nm or more and 490 nm or less.

[0022]

[16] The display device according to any one of [1] to

[15] , wherein the resin composition containing the (A) resin further contains a (C) colorant, and the (C) colorant contains a (C-2) colorant having an absorption maximum in the wavelength range of more than 490 nm to 580 nm.

[0023]

[17] The display device according to any one of [1] to

[15] , wherein the resin composition containing the (A) resin further contains a (C) colorant, and the (C) colorant contains a (C-3) colorant having an absorption maximum in the wavelength range of more than 580 nm to 800 nm.

[0024]

[18] The display device according to any one of [1] to

[15] , wherein the (C) colorant contains (C-1) a colorant having an absorption maximum in a wavelength range of 400 nm or more and 490 nm or less, and further contains (C-2) a colorant having an absorption maximum in a wavelength range of more than 490 nm and less than 580 nm, and (C-3) a colorant having an absorption maximum in a wavelength range of more than 580 nm and less than 800 nm.

[0025]

[19] The display device according to any one of [1] to

[18] , wherein the resin composition containing the resin (A) is positive photosensitive.

[0026] The display device of the present invention has high wiring concealment properties, and can provide a display device with high designability.

[0027] 1 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing an example of a first embodiment of the display device of the present invention; FIG. 2 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing another example of the first embodiment of the display device of the present invention; FIG. 3 is a cross-sectional view (a) of an enlarged designated region A, and a bottom view (b) of the designated region A excluding the light-emitting elements, as viewed from the counter substrate side; FIG. 4 is a cross-sectional view (a) of the light-emitting element driving substrate side of the designated region B cut along a plane parallel to the counter substrate, FIG. 5 is a cross-sectional view (b) of the designated region B at a position not including wiring perpendicular to the counter substrate, and FIG. 6 is a bottom view (c) of the designated region B excluding the counter substrate, as viewed from the counter substrate side; FIG. 6 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing an embodiment of the display device of the present invention having a configuration in which partition walls are provided; FIG. 7 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing an embodiment of the display device of the present invention having a configuration in which driving elements are arranged in a cured film; FIG. 8 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing an embodiment of the display device of the present invention having another configuration in which driving elements are arranged in a cured film; FIG. 9 is a cross-sectional view taken along a plane perpendicular to the support substrate or counter substrate, showing a manufacturing process of an embodiment of the display device of the present invention. 1 is a cross-sectional view taken along a plane perpendicular to the support substrate or the counter substrate, showing another example of a manufacturing process for a display device of the present invention; FIG. 1 is a cross-sectional view taken along a plane perpendicular to the support substrate or the counter substrate, showing another example of a manufacturing process for a display device of the present invention having a configuration in which a partition wall is provided; FIG. 2 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing another embodiment of the display device of the present invention; FIG. 3 is a cross-sectional view taken along a plane perpendicular to the support substrate, showing an embodiment of the display device of the present invention having a configuration in which a partition wall is provided in the cured film; FIG. 4 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing another embodiment of the display device of the present invention; FIG. 5 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing another embodiment of the display device of the present invention; FIG. 6 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing another embodiment of the display device of the present invention; FIG. 7 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing an embodiment of the display device of the present invention having a configuration in which a light-shielding layer is provided; FIG. 8 is a cross-sectional view taken along a plane perpendicular to the support substrate, showing an opening pattern of the cured film; FIG. 9 is a cross-sectional view taken along a plane perpendicular to the support substrate, showing a manufacturing process for an embodiment of the display device of the present invention having a configuration in which a partition wall is provided; 10A and 10B are cross-sectional views taken along a plane perpendicular to the counter substrate, showing one embodiment of a display device of the present invention using light-emitting elements with different connection modes.1 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing one embodiment of a display device of the present invention using light-emitting elements of a different connection mode; FIG. 1 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing one embodiment of a display device of the present invention using light-emitting elements of a different connection mode; FIG. 2 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing one embodiment of a display device of the present invention using light-emitting elements of a different connection mode; FIG. 3 is a cross-sectional view taken along a plane perpendicular to the counter substrate, showing one embodiment of a display device of the present invention using light-emitting elements of a different connection mode; FIG. 4 is a cross-sectional view taken along a plane perpendicular to the element driving substrate, showing one example of a second embodiment of a display device of the present invention; FIG. 5 is a cross-sectional view taken along a plane perpendicular to the element driving substrate, showing one example of a display device of the second embodiment of the present invention; FIG. 6 is a cross-sectional view taken along a plane perpendicular to the support substrate, showing another example of the second embodiment of a display device of the present invention using light-emitting elements of a different connection mode; FIG. 7 is a cross-sectional view taken along a plane perpendicular to the light-emitting element driving substrate, showing one example of a manufacturing process of a display device according to the second embodiment of the present invention.

[0028] Preferred embodiments of the display device of the present invention will be specifically described below, but the present invention is not limited to the following embodiments and can be modified and implemented in various ways depending on the purpose and application.

[0029] A first aspect of the display device of the present invention is a display device having at least wiring, a cured film, and a plurality of light-emitting elements, wherein the light-emitting elements each have an electrode on two different surfaces, at least one of the electrodes is connected to a plurality of wirings extending in the cured film, and the plurality of wirings maintain electrical insulation due to the cured film, and the cured film is a film obtained by curing a resin composition containing (A) resin, and the transmittance of light with a wavelength of 450 nm at a thickness of 1 μm is 0.1% or more and 95% or less.

[0030] In the following description, unless otherwise specified, the first aspect or the second aspect described below is a description common to both aspects.

[0031] The display device according to the first embodiment of the present invention will be described with reference to FIG. 1 as an example.

[0032] In FIG. 1 , the display device 1 has a plurality of light-emitting elements 2 arranged on an opposing substrate 5, and a cured film 3 arranged on the light-emitting elements 2. Here, the light-emitting elements have a polyhedral three-dimensional shape. A polyhedral three-dimensional shape is a three-dimensional shape having multiple faces, preferably having at least one pair of parallel faces. Examples include tetrahedrons, hexahedrons such as rectangular parallelepipeds and cubes, and octahedrons. However, the polyhedral three-dimensional shape is not limited to such regular shapes, and also includes shapes in which the vertices or edges of these shapes are chamfered, and shapes based on these shapes that have recesses, grooves, or steps. Here, a deviation of plus or minus 5° is considered parallel, and the parallel faces or other faces may have irregularities. The light-emitting element has electrodes on two different faces. "Having electrodes on two different faces" means that, in a polyhedral three-dimensional light-emitting element, when one of the faces having an electrode is considered a reference face, the other electrodes are located on a face other than the reference face. Here, the reference surface refers to a surface of a continuous range within the polyhedral three-dimensional shape, and a surface that exists in the same spatial plane but is divided by a groove within the polyhedral three-dimensional shape is considered to be a surface different from the reference surface. Furthermore, when focusing on one light-emitting element, the electrodes provided on the two different surfaces are sometimes referred to as a pair of electrodes.

[0033] In the present invention, the electrodes provided on the light-emitting elements refer to connection sites for transmitting signals for controlling the light emission of the light-emitting elements from wiring to the light-emitting elements. In the embodiment shown in Figure 1, when focusing on one light-emitting element, the light-emitting element has a polyhedral three-dimensional shape, with one electrode on the surface connected to the wiring 4 extending in the cured film 3, and the other electrode on the surface facing the opposing substrate. When viewed as a whole, one electrode of the pair of electrodes provided on each of the plurality of light-emitting elements is connected to each of the plurality of wirings 4 extending in the cured film 3.

[0034] 1 illustrates a configuration in which a total of three layers are laminated by laminating multiple cured films 3 on the cured film 3 arranged so as to be in contact with at least a portion of the light-emitting element 2, but the cured film 3 may also be a single layer. The light-emitting element 2 has electrodes 6 on two different surfaces, and one of the pair of electrodes 6 is connected to a wiring 4 extending in the cured film 3. The multiple wirings 4 extending in the cured film 3 are separated by the cured film 3. With this structure, the multiple wirings 4 maintain electrical insulation due to the cured film 3. The cured film 3 is preferably a cured film obtained by curing a resin composition containing the (A) resin described below.

[0035] Of the pair of electrodes 6, the electrode 6 that is not connected to the wiring 4 extending in the cured film 3 is connected to the wiring 4d. The wiring 4d may be formed on a support substrate described below, or may be formed on the opposing substrate 5. When forming the wiring 4d on the support substrate, the wiring 4d may be formed after forming a temporary attachment layer made of a temporary attachment material on the support substrate. The electrode 6 and the wiring 4d may be connected via a bump, a conductive film, or the like, or may be connected directly.

[0036] The wiring 4d may be covered with the cured film 3 to maintain electrical insulation, or the cured film 3 and the wiring 4d may form a laminated structure of two or more layers. The wiring 4d may be connected to the wiring 4 extending in the cured film 3 arranged so as to contact at least a portion of the light-emitting element 2 via a through-electrode or the like, or may be arranged on the side of the light-emitting element 2 or the side of the partition wall 16 described below and connected to the wiring 4 extending in the cured film 3, or may be connected to the light-emitting element drive substrate 7. Furthermore, the light-emitting element 2 is electrically connected to a drive element 8 attached to the light-emitting element drive substrate 7 provided in a position opposite the counter substrate 5 through the wiring 4 or 4c, thereby controlling the light emission of the light-emitting element 2. The light-emitting element drive substrate 7 is also electrically connected to the wiring 4 via, for example, a bump 10. Furthermore, a barrier metal 9 may be provided to prevent diffusion of metal such as the wiring 4. Note that, hereinafter, the wiring 4c in the figures may be formed on the side of the light-emitting element drive substrate 7, may penetrate the light-emitting element drive substrate 7, or may be connected to the drive element 8 as a wiring constituting the light-emitting element drive substrate.

[0037] 1 illustrates an example in which wiring 4d and an electrode 6 are disposed between the counter substrate 5 and the light-emitting element 2, and further, a cured film 3 is disposed between the counter substrate 5 and the light-emitting element 2 so as to be adjacent to the wiring 4 and the electrode 6. However, this embodiment also includes a configuration in which the wiring 4 and the electrode 6 are formed so as to cover the entire flat surface of the light-emitting element 2, and the cured film 3 is not disposed between the counter substrate 5 and the light-emitting element 2, or a configuration in which the wiring 4 and the electrode 6 shown in FIG. 1 are formed as thin films, in which a resin film 21 described later cannot reach adjacent to the wiring 4 and the electrode 6, and the cured film 3 is not formed between the counter substrate 5 and the light-emitting element 2, resulting in a partial cavity.

[0038] It is important that the cured film 3 has a transmittance of 0.1% or more and 95% or less for light at a wavelength of 450 nm when the cured film 3 has a thickness of 1 μm. This allows the cured film 3 to conceal the wiring 4, suppress glare from the wiring 4, and make it difficult to see from the outside, thereby improving the design.

[0039] The cured film 3 is a film obtained by curing a resin composition containing the resin (A) described below, and the transmittance of light at a wavelength of 450 nm at a standard thickness of 5 μm of the cured film 3 is preferably 0.1% or more and 79% or less. This allows the cured film 3 to conceal the wiring 4, suppress glare from the wiring 4, and make it difficult to see from the outside, thereby improving the design.

[0040] The cured film 3 is a film obtained by curing a resin composition containing the resin (A) described below, and the transmittance of light at a wavelength of 450 nm at a standard thickness of 1 μm of the cured film 3 is preferably 0.1% or more and 25% or less. This allows the cured film 3 to conceal the wiring 4, suppress glare from the wiring 4, make it difficult to see from the outside, and improve the design, and further improve visibility by reducing external light reflection and improving contrast.

[0041] If the transmittance of light at a wavelength of 450 nm at a standard thickness of 1 μm of the cured film 3 is less than 0.1%, there is a concern that problems such as a decrease in the sensitivity and resolution of the resin film before curing may occur. If the light transmittance exceeds 95%, there is a concern that problems such as a decrease in the wiring concealment ability, insufficient suppression of wiring glare, and the wiring being visible from the outside may occur.

[0042] The measurement of the light transmittance at a wavelength of 450 nm when the cured film has a standard thickness of 1 μm may be performed by peeling off the cured film from the display device, or the light transmittance may be measured using a cured film prepared under the conditions of the method for evaluating the light transmittance of a cured film described below. Furthermore, when a multi-layer cured film is formed, any of the cured films may be used for the measurement. The measurement of the light transmittance at a wavelength of 450 nm when the cured film has a standard thickness of 5 μm is similar to the measurement of the light transmittance at a wavelength of 450 nm when the cured film has a standard thickness of 1 μm. When the thickness of the cured film is not 1 μm, the measured transmission spectrum may be converted to a value equivalent to 1 μm according to Lambert's law. When the thickness of the cured film is not 5 μm, the conversion may be performed according to Lambert's law, as in the case when the thickness of the cured film is not 1 μm.

[0043] The materials for the wirings 4, 4c, 4d and the electrodes 6 are not particularly limited, and include metals and conductive films, and known materials may also be used.

[0044] Metals are preferred from the viewpoint of electron mobility, and examples thereof include gold, silver, copper, aluminum, nickel, titanium, molybdenum, and alloys containing these.

[0045] These metals can be formed by wet plating such as electroless plating and electrolytic plating, CVD chemical vapor deposition (CVD) methods such as thermal CVD, plasma CVD and laser CVD, dry plating methods such as vacuum deposition, sputtering and ion plating, and methods in which a metal foil is bonded to a substrate and then etched.

[0046] The conductive film is preferable from the viewpoint of transparency, etc., and examples thereof include a compound containing an oxide of at least one element selected from the group consisting of indium, gallium, zinc, tin, titanium, and niobium as a main component, and a photosensitive conductive paste containing an organic substance and conductive particles, but other known conductive films may also be used. Specific examples of compounds containing an oxide of at least one element selected from the group consisting of indium, gallium, zinc, tin, titanium, and niobium as a main component include indium tin zinc oxide (ITZO), indium gallium zinc oxide (IGZO: InGaZnO), zinc oxide (ZnO), indium zinc oxide (IZO), indium gallium oxide (IGO), indium tin oxide (ITO), and indium oxide (InO).

[0047] These conductive films can be formed by, for example, wet plating such as electroless plating and electrolytic plating; CVD (chemical vapor deposition) methods such as thermal CVD, plasma CVD and laser CVD; dry plating methods such as vacuum deposition, sputtering and ion plating; or a method in which a metal foil is bonded to a substrate and then etched.

[0048] In a photosensitive conductive paste containing an organic substance and conductive particles, the content of the conductive particles is preferably 60% by mass or more and 90% by mass or less. By containing an organic substance in the conductive layer, disconnection at curved surfaces or bent portions can be suppressed, and conductivity can be improved. If the content of the conductive particles is less than 60% by mass, the probability of contact between the conductive particles decreases, resulting in a decrease in conductivity. Furthermore, the conductive particles tend to separate from each other at bent portions of the wiring. The content of the conductive particles is preferably 70% by mass or more. On the other hand, if the content of the conductive particles exceeds 90% by mass, it becomes difficult to form a wiring pattern, and disconnection at bent portions is more likely to occur. The content of the conductive particles is preferably 80% by mass or less.

[0049] Examples of organic materials include epoxy resins, phenoxy resins, acrylic copolymers, and epoxy carboxylate compounds. Two or more of these may be contained. An organic material having a urethane bond may also be contained. By containing an organic material having a urethane bond, the flexibility of the wiring can be improved. Furthermore, the organic material preferably exhibits photosensitivity, which allows for easy formation of fine wiring patterns by photolithography. Photosensitivity can be achieved by, for example, containing a photopolymerization initiator or a component having an unsaturated double bond.

[0050] In the present invention, the conductive particles have an electrical resistivity of 10 －５ It refers to particles composed of a substance with a resistivity of Ω·m or less. Examples of materials constituting the conductive particles include silver, gold, copper, platinum, lead, tin, nickel, aluminum, tungsten, molybdenum, chromium, titanium, indium, alloys of these metals, and carbon particles. It is also preferable to contain two or more types of conductive particles. By containing two or more types of conductive particles, sintering of conductive particles of the same type and volumetric shrinkage during the heat treatment step described below is suppressed, resulting in suppression of volumetric shrinkage of the entire conductive film and improved flexibility.

[0051] The average particle diameter of the conductive particles is preferably 0.005 μm or more and 2 μm or less. Here, the average particle diameter refers to the average particle diameter of the larger particles when two or more types of conductive particles are contained. When the average particle diameter of the conductive particles is 0.005 μm or more, the interaction between the conductive particles can be appropriately suppressed, and the dispersed state of the conductive particles can be maintained more stably. The average particle diameter of the conductive particles is more preferably 0.01 μm or more. On the other hand, when the average particle diameter of the conductive particles is 2 μm or less, it becomes easier to form a desired wiring pattern. The average particle diameter of the conductive particles is more preferably 1.5 μm or less.

[0052] The thickness of the conductive film is preferably 2 μm or more and 10 μm or less. When the thickness of the conductive film is 2 μm or more, breakage at the bent portion can be further suppressed and the conductivity can be further improved. The thickness of the conductive film is more preferably 4 μm or more. On the other hand, when the thickness of the conductive film is 10 μm or less, the wiring pattern can be more easily formed in the manufacturing process. The thickness of the conductive film is more preferably 8 μm or less.

[0053] 10 illustrates another embodiment of the display device of the present invention, in which a cured film 21 is provided in the display device of FIG. 1 so as to be in contact with at least a portion of the light-emitting element 2. The cured film 21 so as to be in contact with at least a portion of the light-emitting element 2 may be made of a cured film obtained by curing a resin composition containing the (A) resin or a resin sheet, or may be made of a material other than a cured film obtained by curing a resin composition containing the (A) resin or a resin sheet, and known materials such as epoxy resin, silicone resin, and fluororesin may be used.

[0054] In the present invention, the light emitting element driving substrate 7 may be a substrate having elements with a driving function, and preferably has the driving elements 8 connected thereto.

[0055] The light-emitting element driving substrate 7 is not particularly limited, and known substrates can be used. Examples include glass substrates, sapphire substrates, printed wiring boards, TFT array substrates, and ceramics. Wiring may be formed on at least one surface of the glass substrate or sapphire substrate. When a printed wiring board is used, it can be connected to the driving elements 8, bumps 10, wiring 4, etc. without forming wiring 4c.

[0056] In the present invention, the total thickness of the cured film is preferably 5 μm or more and 100 μm or less.

[0057] When the total thickness of the cured film is 5 μm or more and 100 μm or less, the light transmittance of the cured film 3 is low, so that the cured film 3 conceals the wiring 4, suppresses glare from the wiring 4, and makes it difficult to see from the outside, thereby improving the design. Furthermore, it becomes possible to reduce the height of the display device having the light-emitting element itself, suppress wiring defects such as wiring shorts due to shorter wiring distances, suppress loss, and improve high-speed response. In addition, visibility can be improved by reducing external light reflection and improving contrast.

[0058] The total thickness of the cured film refers to the total thickness of the continuous cured film layer in which at least a portion of one cured film is in contact with another cured film. For example, when a plurality of cured films 3 are stacked as shown in FIG. 1 above, the range indicated by 20 in FIG. 1 is the total thickness of the cured film layer. The total thickness is preferably 5 μm or more and 70 μm or less, more preferably 5 μm or more and 60 μm or less. If it is less than 5 μm, there is a concern that the wiring will not be sufficiently protected, resulting in wiring defects such as short-circuiting of the wiring. If it exceeds 100 μm, there is a concern that the light extraction efficiency will be insufficient, and there may be inconveniences in terms of reducing the height of the display device itself, suppressing wiring defects such as short-circuiting of the wiring due to shortened wiring distance, suppressing loss reduction, and improving high-speed response.

[0059] When a plurality of cured films are laminated, the number of layers of the cured film is preferably 2 to 10. From the viewpoint of arranging a plurality of light-emitting elements, the cured film preferably has one or more layers, and further, by having two or more layers, the number of wirings that can be connected to the light-emitting elements can be increased, allowing a plurality of light-emitting elements to be arranged, and from the viewpoints of suppressing wiring defects such as short-circuiting of wiring due to a low package height or a short wiring distance, reducing loss, and improving high-speed response, 10 or less layers are preferred.

[0060] In the present invention, the cured film is provided with an opening pattern penetrating through the film in the thickness direction, and the wiring is disposed at least in the opening pattern, and it is preferable that the maximum length of the bottom surface portion of the wiring formed at a position in contact with the light-emitting element is 2 μm or more and 20 μm or less.

[0061] 2 shows an enlarged cross-sectional view (a) of a designated region A in FIG. 1 and a bottom view (b) of the designated region A excluding the light-emitting element, as viewed from the opposing substrate side. In the enlarged cross-sectional view (a) of the designated region A in FIG. 2, a cured film 3 is provided on the light-emitting element 2. An opening pattern 12 is provided in the cured film 3, and a diagram showing wiring 4 formed in the opening pattern 12 is shown. A bottom portion 13 of the wiring 4 extends into the cured film 3 up to the position where the wiring 4 contacts the electrode 6 of the light-emitting element 2, and shows the shape of the wiring 4 at the point of contact.

[0062] In the bottom view (b) of the surface of the designated area A of FIG. 2 , excluding the light-emitting element, viewed from the opposing substrate side, the bottom surface 13 of the wiring 4 extending into the cured film 3 with the light-emitting element 2 removed is viewed from below, showing the bottom surface 13. In the bottom view (lower part) of the designated area A of FIG. 2 , excluding the light-emitting element, the bottom surface 13 of the wiring 4 extending into the cured film 3 with the light-emitting element 2 removed is viewed from below, showing the bottom surface 13. The shape of the bottom surface 13 may vary depending on the product and the shape of the light-emitting element. In the case of a circular shape, the diameter is defined as the longest length 14; in the case of an elliptical shape, the major axis is defined as the longest length 14; and in the case of a polygon such as a rectangle, the longest diagonal line connecting the vertices of the corners is defined as the longest length 14. Note that the bottom surface 13 in the bottom view (b) of the surface of the designated area A of FIG. 2 , excluding the light-emitting element, viewed from the opposing substrate side, shows an example of a circular shape.

[0063] This configuration allows for the application of minute light-emitting elements and enables high-density packaging of multiple light-emitting elements, resulting in a display device with high-resolution light-emitting elements in a wide range of sizes. Furthermore, it is possible to form fine wiring, which increases the number of wirings that can be formed per unit area, thereby reducing the overall thickness of the cured film. Because the light transmittance of the cured film 3 is low, the cured film 3 conceals the wiring 4, suppressing glare from the wiring 4 and making it less visible from the outside, thereby improving design. Furthermore, it is possible to reduce the height of the display device itself that includes light-emitting elements, suppress wiring defects such as wiring shorts due to shorter wiring distances, reduce loss, and improve high-speed response. In addition, visibility can be improved by reducing external light reflection and improving contrast.

[0064] In the present invention, the maximum length of the bottom surface of the wiring formed in proximity to the light-emitting element is preferably 2 μm or more and 20 μm or less. This configuration allows for the application of minute light-emitting elements and enables high-density packaging of multiple light-emitting elements, resulting in a display device having high-resolution light-emitting elements in a wide range of sizes. Furthermore, it becomes possible to form finer wiring, increasing the number of wirings that can be formed per unit area, thereby reducing the overall thickness of the cured film. Since the cured film 3 has low light transmittance, the cured film 3 conceals the wiring 4, suppressing glare from the wiring 4 and making it less visible from the outside, thereby improving design. Furthermore, it is possible to reduce the height of the display device having the light-emitting element itself, suppress wiring defects such as wiring shorts due to shorter wiring distances, reduce loss, and improve high-speed response. In addition, visibility can be improved by reducing external light reflection and improving contrast.

[0065] From the viewpoint of applying minute light-emitting elements and achieving high-density mounting of light-emitting elements, the maximum length of the bottom surface of the wiring is preferably 2 μm or more and 15 μm or less, more preferably 2 μm or more and 10 μm or less, and even more preferably 2 μm or more and 5 μm or less. If it is less than 2 μm, poor connection with the light-emitting element 2 may occur, and if it exceeds 20 μm, it may hinder the application of minute light-emitting elements and high-density mounting.

[0066] The thickness of the cured film is preferably 1.1 times or more and 20.0 times or less the thickness of the wiring.

[0067] The thickness of the wiring, as explained in the enlarged cross-sectional view (a) of the designated area A in FIG. 2 , refers to the thickness a of the wiring 4 arranged on the surface of the cured film 3, and does not include the thickness of the wiring 4b extending into the opening pattern penetrating the cured film 3 in the thickness direction. The thickness of the wiring is preferably 0.1 μm or more and 10 μm or less, and more preferably 3 μm or more and 10 μm or less. By making the thickness of the wiring 0.1 μm or more and 10 μm or less, it is possible to reduce the height of the display device having the light-emitting element itself, suppress wiring defects such as wiring shorts due to shortened wiring distances, suppress low loss, and improve high-speed response. Furthermore, by making the thickness 3 μm or more and 10 μm or less, wiring resistance can be reduced, which can contribute to suppressing power consumption and improving brightness.

[0068] The thickness of the cured film refers to the thickness of the cured film 3a covering the wiring 4a, as explained with reference to the enlarged cross-sectional view (a) of the designated area A in FIG.

[0069] This allows for the production of a highly reliable cured film that also functions as a protective film for appropriate wiring and prevents wiring defects such as short circuits.

[0070] The thickness of the wiring may be the same or different in each layer. When the thicknesses are different, as an example, in FIG. 1, it is preferable that the thickness of the wiring closer to the bumps 10 is thicker than the thickness of the wiring closer to the light-emitting element 2. This makes it possible to suppress wiring defects when connecting the light-emitting element driving substrate 7 using the bumps 10, and to obtain a highly reliable display device.

[0071] In the present invention, it is preferable that the cured film covers a surface of the light-emitting element other than the light extraction surface. Note that the light extraction surface is considered to be the light extraction surface even when only a portion of the surface of the light-emitting element is covered with the cured film, as long as there is an area from which light can be extracted.

[0072] As an example, Figure 3 shows (a) a cross-sectional view of the light-emitting element driving substrate side of the designated area B in Figure 1 cut along a plane parallel to the opposing substrate, (b) a cross-sectional view at a position that does not include wiring perpendicular to the opposing substrate of the designated area B, and (c) a bottom view of the surface of the designated area B excluding the opposing substrate, as seen from the opposing substrate side.

[0073] In the cross-sectional view (a) of the light-emitting element driving substrate side of the designated region B in Fig. 3 cut along a plane parallel to the opposing substrate, the light-emitting element 2 is covered with the cured film 3, and the wiring 4 connected to the electrode 6 of the light-emitting element and extending into the cured film 3 is shown from above. The cross-sectional shape of the wiring 4 may be circular or polygonal.

[0074] In the cross-sectional view (b) of FIG. 3 at a position not including the wiring perpendicular to the opposing substrate, it is shown that the periphery of the light-emitting element 2 is covered with the hardened film 3.

[0075] In the bottom view (c) of the surface of the designated region B in Figure 3 excluding the counter substrate, as viewed from the counter substrate side, the light-emitting element 2 is covered with the cured film 3, and the other electrode 6 of the light-emitting element is shown from the bottom. The cross-sectional shape of the electrode 6 may be circular or polygonal. The light-emitting element 2 may be covered with the cured film 3 except for the electrode 6. In this case, the surface on which the electrode 6 is disposed is the light extraction surface.

[0076] 1 and 3, by covering the entire side surface and the top surface of the light-emitting element 2 with the cured film 3, the light-emitting element 2 can be protected from external impact. This is also preferable because it can flatten any steps that arise due to the arrangement of the light-emitting element 2 and also makes it easier to attach the light-emitting element 2 to the opposing substrate 5.

[0077] The cured film 3 covering the surfaces of the light-emitting element 2 other than the light extraction surface has the high wiring concealing property described above, thereby suppressing the glare of the wiring 4, making it difficult to see from the outside, and improving the design.

[0078] A display device according to a second aspect of the present invention is a display device having at least a substrate having wiring and / or TFTs, a cured film, and a plurality of light-emitting elements, wherein the light-emitting elements each have electrodes on two different surfaces, at least a portion of the wiring and / or TFTs is in contact with the cured film, the cured film is a film obtained by curing a resin composition containing (A) resin, and the transmittance of the cured film at a thickness of 1 μm for light with a wavelength of 450 nm is 0.1% or more and 95% or less.

[0079] The display device according to the second aspect of the present invention will be described with reference to FIG. 25 as an example.

[0080] 25 , in the display device 1, the cured film 3 is disposed so that at least a portion of the substrate having wiring and / or TFTs is in contact with the cured film 3. The substrate having wiring and / or TFTs is, for example, a light-emitting element driving substrate 7, and an example thereof is a TFT array substrate having wiring 4 disposed thereon.

[0081] Next, wiring 4e is disposed on at least a part of the surface of the cured film 3 and on a part of the opening pattern of the cured film 3, and then the light-emitting element 2 having electrodes on two different surfaces is disposed on the wiring 4e.

[0082] In the embodiment shown in Figure 25, a polyhedral three-dimensional light-emitting element has one electrode on the surface connected to the wiring 4e and the other electrode on the surface facing the opposing substrate. Also shown is a configuration in which a cured film 3 is provided between or around the light-emitting elements 2. The electrode 6 not connected to the wiring 4e of a pair of electrodes 6 is connected to the wiring 4d. The wiring 4d may be formed on the opposing substrate 5. The electrode 6 and the wiring 4d may be connected via a bump, a conductive film, or the like, or may be connected directly. The wiring 4d may be connected to the wiring 4 extending through the cured film 3 arranged so as to contact at least a portion of the light-emitting element 2 via a through-electrode, or may be connected to the wiring 4e by wiring arranged on the side of the light-emitting element 2 or the side of the cured film 3 described below, or may be connected to the light-emitting element drive substrate 7. Furthermore, the light-emitting element 2 is electrically connected to the drive element 8 attached to the light-emitting element drive substrate 7 arranged opposite the opposing substrate 5 via the wiring 4 or 4c, thereby controlling the light emission of the light-emitting element 2. The light-emitting element drive substrate 7 is also electrically connected to the wiring 4 via, for example, a bump 10. Furthermore, a barrier metal 9 may be provided to prevent diffusion of metal such as the wiring 4. Note that the wiring 4c in the following drawings may be formed on the side surface of the light-emitting element drive substrate 7, may pass through the light-emitting element drive substrate 7, or may be connected to the drive element 8 as a wiring constituting the light-emitting element drive substrate.

[0083] As other examples of the display device according to the second aspect of the present invention, for example, configurations such as those shown in FIGS. 26 to 28 are preferable.

[0084] In the display device according to the second aspect of the present invention, the total thickness of the cured film is preferably 1 μm or more and 20 μm or less. By making the total thickness of the cured film 1 μm or more and 20 μm or less, it is possible to suppress absorption of light emitted in all directions from the light-emitting element 2 in the cured film 3, thereby increasing the light extraction efficiency and improving the brightness. Furthermore, it is possible to reduce the height of the display device having the light-emitting element itself, suppress wiring defects such as short circuits due to shorter wiring distances, suppress loss, and improve high-speed response.

[0085] In the second aspect of the present invention, the total thickness of the cured film refers to the total thickness of a continuous cured film layer in which at least a portion of one cured film is in contact with another cured film. For example, the range shown by 20 in Figure 25 above is the total thickness of the cured film layer. The total thickness is preferably 1 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less. If the thickness is less than 1 μm, the wiring is not sufficiently protected, which may lead to wiring defects such as short circuits. If the thickness is more than 10 μm, it becomes difficult to form fine wiring, which may lead to problems such as wiring defects such as short circuits.

[0086] In the present invention, it is preferable that a partition wall having a thickness equal to or greater than the thickness of the light emitting element is provided between the plurality of light emitting elements.

[0087] 4, it is preferable to have partition walls 15 in a repeating pattern corresponding to the number of pixels of the display device 1 having the light-emitting elements 2, i.e., between or around each light-emitting element 2. The electrode 6 and the wiring 4 or 4d may be connected via a bump or a conductive film, or may be connected directly. This configuration is preferable because it facilitates bonding to the opposing substrate 5 which may include the wiring 4d.

[0088] The thickness of the partition wall is preferably larger than the thickness of each light emitting element, and specifically, is preferably 5 μm or more and 120 μm or less.

[0089] The partition walls may be formed from a cured film obtained by curing a resin composition containing the (A) resin, or may be formed from a material other than the resin composition containing the (A) resin, such as a known material such as an epoxy resin, a (meth)acrylic polymer, a polyurethane, a polyester, a polyolefin, or a polysiloxane. By using these materials, partition walls with excellent adhesion can be formed.

[0090] In order to suppress light leakage from the light-emitting elements and color mixing between pixels and improve contrast, a light-shielding portion may be provided on the side surface of the partition wall or on the partition wall itself. The light-shielding portion is, for example, a portion containing a black pigment. Furthermore, a reflective portion may be provided on the side surface of the partition wall to reflect light emitted from the light-emitting elements toward the partition wall and thereby improve light extraction efficiency and brightness. The reflective portion is, for example, a portion containing a white pigment.

[0091] It is preferable that a partition wall having a thickness equal to or greater than the thickness of the light emitting element is disposed between the plurality of light emitting elements in the cured film covering the light emitting elements.

[0092] As another embodiment in which partition walls are provided, as shown in FIG. 11, a configuration in which partition walls 15 are provided between or around the light emitting elements 2 in the cured film 3 covering the light emitting elements 2 is exemplified.

[0093] 11 may be made of a material other than the resin composition containing the (A) resin, and may be made of known materials such as epoxy resin, (meth)acrylic polymer, polyurethane, polyester, polyolefin, polysiloxane, etc. By using these materials, partition walls with excellent adhesion can be formed.

[0094] The partition walls are preferable because they can serve as markers for subsequent transfer of light-emitting elements and can also be used as photospacers, thereby improving the efficiency of light-emitting element transfer. Furthermore, in order to suppress light leakage from the light-emitting elements and color mixing between pixels and improve contrast, light-shielding portions may be provided on the side surfaces of the partition walls or on the partition walls themselves. The light-shielding portions are, for example, portions containing black pigments.

[0095] The light emitted from the light emitting element toward the partition wall can be reflected to increase the light extraction efficiency, and a reflective portion may be provided on the side surface of the partition wall to improve brightness. The reflective portion is, for example, a portion containing a white pigment.

[0096] In the present invention, a light diffusing layer may be provided around the light emitting element, the cured film, or the wiring.

[0097] In the present invention, the light emitting element is preferably an LED having a side length of 5 μm or more and 700 μm or less, and more preferably an LED having a side length of 5 μm or more and 100 μm or less.

[0098] An LED is composed of a PN junction, where a P-type semiconductor and an N-type semiconductor are joined. When a forward voltage is applied to an LED, electrons and holes move within the chip, causing a current to flow. The electrons and holes combine to create an energy difference, which converts the excess energy into light energy and emits light. The wavelength of light emitted from an LED varies depending on the compound that makes up the semiconductor, such as GaN, GaAs, InGaAlP, or GaP, and this difference in wavelength determines the emitted color. While white is typically displayed by mixing two or more different colors of light, LEDs can significantly improve color reproducibility by mixing the three primary colors of red, green, and blue, making it possible to display a more natural white color.

[0099] The LED may be of a bullet type, chip type, polygonal type, etc., but the chip type or polygonal type is preferred from the viewpoint of miniaturization of the LED. Furthermore, it is preferable that the length of one side of the LED is 5 μm or more and 700 μm or less, since this allows for the arrangement of multiple chips, and it is even more preferable that the length of one side of the LED is 5 μm or more and 100 μm or less.

[0100] The light-emitting element has electrodes on two different surfaces. The term "two different surfaces" means that, for a light-emitting element having two or more surfaces, when one of the surfaces having an electrode is taken as a reference surface, the other electrodes are provided on a surface different from the reference surface.

[0101] In the present invention, it is preferable that an electrode be provided on each of the opposing surfaces sandwiching the light-emitting element. It is also preferable that an electrode be provided on each of the adjacent surfaces of the light-emitting element. Examples of providing electrodes on two different surfaces of the light-emitting element include structures such as those shown in FIGS. 1 and 20 in which electrodes 6 are arranged on opposing surfaces sandwiching the light-emitting element 2, and examples of providing electrodes on each of the adjacent surfaces of the light-emitting element include a structure such as that shown in FIG. 21. By providing electrodes on each of the opposing surfaces sandwiching the light-emitting element, or by providing electrodes on each of the adjacent surfaces of the light-emitting element, it is possible to reduce the size of the light-emitting element, thereby enabling a display device with high resolution due to reduced costs and high-density packaging to be obtained.

[0102] In the present invention, it is also preferable to provide electrodes on each discontinuous surface. Examples of discontinuous surfaces include surfaces that are not continuous but have steps, such as those shown in FIGS. 22 to 24 . By providing electrodes 6 on the discontinuous surfaces, it is possible to control the light-emitting area in the light-emitting element and improve the productivity and light-emitting efficiency of the light-emitting element. Regarding methods for mounting the light-emitting element on a substrate such as a light-emitting element driving substrate 7 on which a cured film 3 of the light-emitting element is disposed, pick-and-place methods and mass transfer methods have been proposed, but the methods are not limited to these.

[0103] Examples of methods for mounting light-emitting elements on a substrate include a method in which light-emitting elements emitting red, green, and blue are arranged in a matrix at predetermined positions on the substrate, and a method in which a single type of light-emitting element, such as a light-emitting element emitting red or blue or an ultraviolet light-emitting element emitting ultraviolet light, is arranged on the substrate. The former method may use light-emitting elements emitting red, green, and blue, respectively, or may use a vertical stack of light-emitting elements emitting red, green, and blue. The latter method facilitates the array mounting of light-emitting elements. In this case, wavelength conversion materials such as quantum dots can be used to create red, green, and blue subpixels to achieve a full-color display. Furthermore, two or more light-emitting elements may be packaged and then mounted on a substrate.

[0104] Known wavelength conversion materials can be used. For example, when using light-emitting elements that emit blue light, it is preferable to first prepare a light-emitting element array substrate on which only light-emitting elements that emit blue light are arranged and mounted, and then arrange wavelength conversion layers that are excited by blue light and emit red or green light at positions corresponding to the red and green subpixels. This makes it possible to form red, green, and blue subpixels using only light-emitting elements that emit blue light.

[0105] On the other hand, when ultraviolet light-emitting elements that emit ultraviolet light are used, it is preferable to first prepare a light-emitting element array substrate on which only ultraviolet light-emitting elements are arranged and mounted, and then arrange wavelength conversion layers that are excited by ultraviolet light and emit red, green, and blue light at positions corresponding to the red, green, and blue subpixels. This makes it possible to suppress the difference in light emission angle depending on the color of the subpixel. Known wavelength conversion layers can be used, and color filters, etc., may also be used as needed.

[0106] The counter substrate in the present invention is not particularly limited, and known substrates can be used. Examples include a glass plate, a resin plate, a resin film, a sapphire substrate, a printed wiring board, a TFT array substrate, and ceramics. The glass plate is preferably made of alkali-free glass. The resin plate and resin film are preferably made of polyester, (meth)acrylic polymer, transparent polyimide, polyethersulfone, and the like. The thickness of the glass plate and resin plate is preferably 1 mm or less, and more preferably 0.8 mm or less. The resin film is preferably made of 100 μm or less.

[0107] The display device of the present invention preferably includes a driving element, and the light-emitting element is electrically connected to the driving element through wiring extending into the cured film. The display device includes a driving element, and the light-emitting element is electrically connected to the driving element through wiring extending into the cured film, so that one or more light-emitting elements can be individually switched. Examples of the driving element include a driver IC, and one or more driver ICs may be used for a package containing one or more light-emitting elements or multiple light-emitting elements consisting of red, blue, green, etc., according to function.

[0108] As a configuration of the arrangement of the driving elements, a configuration in which the driving elements 8 are arranged in the cured film 3 on the opposing substrate 5 near the light emitting element 2, as shown in Fig. 5, is preferred. Also, a configuration in which the driving elements 8 are arranged in the cured film 3 at a position above the light emitting element 2, as shown in Fig. 6, is preferred. This makes it possible to suppress wiring defects such as short circuits due to shortened wiring distances, suppress loss, and improve high-speed response.

[0109] In the present invention, it is preferable that the display device further includes a driving element and a substrate, the driving element being connected to the light-emitting elements through wiring, and at least a portion of the wiring extending to a side surface of the substrate. By including a driving element and a substrate, the driving element being connected to the light-emitting elements through wiring, and at least a portion of the wiring extending to a side surface of the substrate, it is possible to individually switch-drive a plurality of light-emitting elements, reduce the height and improve the high-speed response of the display device itself, and further reduce the size and narrow the frame of the display device.

[0110] The substrate is not particularly limited, as with the light-emitting element drive substrate 7, and known substrates can be used. Examples include glass substrates, sapphire substrates, TFT array substrates, ceramics, etc. The wiring that extends at least partially to the side surface of the substrate is preferably arranged as shown in 4c in Figures 1, 4, and 12 to 14.

[0111] In the present invention, it is preferable to further provide a light-shielding layer between the plurality of light-emitting elements. By providing a light-shielding layer between the plurality of light-emitting elements, it is possible to suppress light leakage from the light-emitting elements and color mixing between pixels, and improve contrast, without significantly impairing the light extraction efficiency.

[0112] The light-shielding layer may be composed of a cured film obtained by curing a resin composition containing (A) resin and (E) colorant, or may be composed of a material other than the resin composition containing (A), such as an epoxy resin, (meth)acrylic polymer, polyurethane, polyester, polyolefin, or polysiloxane. The (E) colorant may be a black pigment, such as black organic pigments such as carbon black, perylene black, or aniline black; graphite; or inorganic pigments such as metal fine particles of titanium, copper, iron, manganese, cobalt, chromium, nickel, zinc, calcium, or silver; metal oxides, composite oxides, metal sulfides, metal nitrides, or metal oxynitrides. A black color may also be achieved by combining a red pigment and a blue pigment, or, if necessary, a yellow pigment or other pigment. A dye may also be used. Two or more colorants may be used.

[0113] The resin composition containing the (A) resin and the (E) colorant may be made photosensitive, and a (B) photosensitizer described below may be used.

[0114] A preferred method for producing a resin composition containing the (A) resin and the (E) colorant is, for example, to use a disperser to disperse a resin solution containing the (A) resin, the (E) colorant, and optionally a dispersant and an organic solvent, to prepare a colorant dispersion with a high colorant concentration, and then to add the (A) resin and, optionally, other components such as a photosensitizer, followed by stirring. Filtration may be performed as necessary.

[0115] Examples of dispersing machines include ball mills, bead mills, sand grinders, three-roll mills, and high-speed impact mills. Among these, bead mills are preferred for improving dispersion efficiency and achieving fine dispersion. Examples of bead mills include co-ball mills, basket mills, pin mills, and dyno mills. Examples of beads used in bead mills include titania beads, zirconia beads, and zircon beads. The bead diameter of the bead mill is preferably 0.03 mm or more and 1.0 mm or less. (E) When the primary particle diameter of the colorant and the particle diameter of the secondary particles formed by aggregation of the primary particles are small, it is preferable to use fine beads with a diameter of 0.03 mm or more and 0.10 mm or less. In this case, a bead mill equipped with a centrifugal separator capable of separating the fine beads from the dispersion is preferred. On the other hand, when dispersing a colorant containing coarse particles on the submicron scale, it is preferable to use beads with a diameter of 0.10 mm or more to obtain sufficient crushing power.

[0116] The resin composition containing the resin (A) and the colorant (E) can be applied to various substrates, dried, and then heat-treated to obtain a light-shielding layer. If the resin composition has photosensitivity, it can be exposed to actinic rays described below, and then developed and heat-treated to obtain a patterned light-shielding layer.

[0117] The thickness of the light-shielding layer is preferably 0.1 μm or more and 5 μm or less. When the thickness of the light-shielding layer is 0.1 μm or more, light leakage from the light-emitting element and color mixing between pixels can be suppressed, and contrast can be improved. The thickness of the light-shielding layer is more preferably 0.5 μm or more. On the other hand, when the thickness of the wiring is 5 μm or less, light leakage from the light-emitting element and color mixing between pixels can be suppressed and contrast can be improved without significantly impairing the light extraction efficiency. The thickness of the light-shielding layer is more preferably 4 μm or less.

[0118] The light-shielding layer is a colored film formed on a 0.7 mm thick alkali-free glass substrate to a thickness of 1.0 μm. The reflective chromaticity values ​​(a*, b*) measured from the glass surface preferably fall within the ranges of -0.5≦a*≦1.0 and -1.0≦b*≦0.5, and more preferably fall within the ranges of -0.5≦a*≦0.5 and -1.0≦b*≦0.4. Reflected chromaticity is an index of the color tone of an image reflected in the colored film, and the closer the reflection chromaticity is to (a*, b*) = (0.0, 0.0), the more achromatic the reflection tone. On the other hand, the reflection tone of black display in liquid crystal display devices and organic EL displays generally has a negative b* value, resulting in a bluish hue. Therefore, a negative b* value is preferred for decorative films used in display devices.

[0119] The reflection chromaticity (L*, a*, b*) of the colored film can be obtained by measuring the total reflection chromaticity (SCI) of light incident from a transparent substrate under the measurement conditions of standard illuminant D65 (color temperature 6504K), a viewing angle of 2° (CIE1976), atmospheric pressure, and 20°C using a spectrophotometer (CM-2600d; manufactured by Konica Minolta, Inc.) calibrated with a white calibration plate (CM-A145; manufactured by Konica Minolta, Inc.).

[0120] A preferred configuration of the light-shielding layer is, for example, the configuration shown by 25 in Fig. 15. The light-shielding layer 25 may be in contact with the light-emitting element 2 or may be separated from it.

[0121] In the present invention, the cured film obtained by curing the resin composition containing the (A) resin has a light transmittance of 0.1% or more and 95% or less at a wavelength of 450 nm at a thickness of 1 μm, thereby providing the high wiring concealment described above, suppressing glare on the wiring, making it difficult to see from the outside, and improving design properties.

[0122] The transmittance of light at a wavelength of 450 nm at a standard thickness of 5 μm of the cured film is preferably 0.1% or more and 79% or less, thereby suppressing glare from the wiring, making it less visible from the outside, and improving design properties.

[0123] The transmittance of light at a wavelength of 450 nm at a standard thickness of 1 μm of the cured film is preferably 0.1% or more and 25% or less, thereby suppressing glare of the wiring, making it difficult to see from the outside, improving design, and further improving visibility by reducing external light reflection and improving contrast.

[0124] If the transmittance of light at a wavelength of 450 nm at a standard thickness of 1 μm of the cured film is less than 0.1%, there is a concern that problems such as a decrease in the sensitivity and resolution of the resin film before curing may occur. If the light transmittance exceeds 95%, there is a concern that problems such as a decrease in the wiring concealment ability and insufficient suppression of wiring glare, which may be visible from the outside, may occur.

[0125] Furthermore, the (A) resin preferably has high heat resistance, specifically, it is preferable that the resin is less likely to deteriorate during or after heat treatment at high temperatures of 160° C. or higher. Such a cured film is preferable because it reduces the amount of outgassing, which is one of the excellent properties of cured films used in display devices, such as insulating films, protective films, and partition walls.

[0126] From the viewpoint of forming a desired opening pattern by exposure and development, the resin (A) preferably has high light transmittance at the exposure wavelength before curing. To obtain such a property, it is preferable to shorten the conjugated chain derived from the aromatic ring of the resin or to reduce the charge transfer within or between molecules, for example.

[0127] For the purpose of protecting the wiring, it is preferable that the processability is excellent even for a thick film having a thickness of 10 μm or more.

[0128] The resin (A) is not particularly limited, but is preferably an alkali-soluble resin from the viewpoint of reducing environmental impact. Alkali-soluble resins are defined as follows: a solution of the resin dissolved in γ-butyrolactone is applied to a silicon wafer and prebaked at 120°C for 4 minutes to form a prebaked film with a film thickness of 10 μm±0.5 μm. Here, prebaking refers to a process of heating and drying the applied film, and the prebaked film refers to the film obtained after the heating and drying. The term "prebaked film" is also synonymous with "resin film." The prebaked film is then immersed in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide at 23±1°C for 1 minute, and the film thickness reduction is determined after rinsing with pure water. A prebaked film with a dissolution rate of 50 nm / min or higher is defined as alkali-soluble.

[0129] The resin (A) preferably contains one or more resins selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, polybenzoxazole precursor, and copolymers thereof. The resin (A) may contain these resins alone or in combination.

[0130] Polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor will be described.

[0131] The polyimide is not particularly limited as long as it has an imide ring. The polyimide precursor is not particularly limited as long as it has a structure that becomes a polyimide having an imide ring by dehydration ring closure, and can contain polyamic acid, polyamic acid ester, etc. The polybenzoxazole is not particularly limited as long as it has an oxazole ring. The polybenzoxazole precursor is not particularly limited as long as it has a structure that becomes a polybenzoxazole having a benzoxazole ring by dehydration ring closure, and can contain polyhydroxyamide, etc.

[0132] The polyimide has a structural unit represented by general formula (1), the polyimide precursor and the polybenzoxazole precursor have a structural unit represented by the following general formula (2), and the polybenzoxazole has a structural unit represented by general formula (3). Two or more of these may be contained, or a resin may be contained in which the structural unit represented by general formula (1), the structural unit represented by general formula (2), and the structural unit represented by general formula (3) are copolymerized.

[0133]

[0134] In general formula (1), V represents a tetravalent to decavalent organic group having 4 to 40 carbon atoms, W represents a divalent to octavalent organic group having 4 to 40 carbon atoms, and a and b each represent an integer of 0 to 6. １ and R ２ represents a group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, and a thiol group, and a plurality of R １ and R ２ may be the same or different.

[0135]

[0136] In the general formula (2), X and Y each independently represent a divalent to octavalent organic group having 4 to 40 carbon atoms. ３ and R ４ each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, c and d each represent an integer of 0 to 4, and e and f each represent an integer of 0 to 2.

[0137]

[0138] In the general formula (3), T and U each independently represent a divalent to octavalent organic group having 4 to 40 carbon atoms.

[0139] In order to impart alkali solubility to the (A) resin, it is preferable that a + b > 0 in general formula (1). Also, it is preferable that c + d + e + f > 0 in general formula (2). In the case of a polyimide precursor, it is preferable that X and Y in general formula (2) have aromatic groups. Furthermore, X in general formula (2) has an aromatic group, e > 2, and has a carboxy group or a carboxy ester group at the ortho position of the aromatic amide group, resulting in a structure in which an imide ring is formed by dehydration ring closure.

[0140] In the case of a polybenzoxazole precursor, X in general formula (2) has an aromatic group, d>0, and has a hydroxyl group at the ortho-position of the aromatic amide group, and forms a structure that forms a benzoxazole ring by dehydration ring closure.

[0141] In the resin (A), the repeating number n of the structural unit represented by general formula (1), general formula (2), or general formula (3) is preferably 5 to 100,000, and more preferably 10 to 100,000.

[0142] The (A) resin may have other structural units in addition to the structural units represented by general formula (1), general formula (2), or general formula (3). Examples of other structural units include, but are not limited to, cardo structures and siloxane structures. In this case, it is preferable that the structural units represented by general formula (1) or general formula (2) are the main structural units. Here, the term "main structural units" refers to structural units represented by general formula (1), general formula (2), or general formula (3) that account for 50 mol% or more, and more preferably 70 mol% or more, of the total number of structural units.

[0143] In the above general formula (1), V-(R １ ) ａ In the above general formula (2), (OH) ｃ -X-(COOR ３ ) ｅIn the general formula (3), T represents an acid residue. V represents a tetravalent to decavalent organic group having 4 to 40 carbon atoms, and is preferably an organic group having 4 to 40 carbon atoms and containing an aromatic ring or a cyclic aliphatic group. X and T represent divalent to octavalent organic groups having 4 to 40 carbon atoms, and is preferably an organic group having 4 to 40 carbon atoms and containing an aromatic ring or an aliphatic group.

[0144] Examples of acid components constituting the acid residue include dicarboxylic acids such as terephthalic acid, isophthalic acid, diphenyl ether dicarboxylic acid, bis(carboxyphenyl)hexafluoropropane, biphenyl dicarboxylic acid, benzophenone dicarboxylic acid, triphenyl dicarboxylic acid, suberic acid, dodecafluorosuberic acid, azelaic acid, sebacic acid, hexadecafluorosebacic acid, 1,9-nonanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, and octadecane dicarboxylic acid. Examples of tricarboxylic acids include trimellitic acid, trimesic acid, diphenyl ether tricarboxylic acid, and biphenyl tricarboxylic acid. Examples of tetracarboxylic acids include pyromellitic acid, 3,3',4,4'-biphenyl tetracarboxylic acid, and 2,3,3',4'-biphenyl tetracarboxylic acid. tetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, 3,3',4,4'-diphenylethertetracarboxylic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, 2,2',3,3'-benzophenonetetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)propane, 2,2-bis(2,3-dicarboxyphenyl)propane, 1,1-bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(2,3-dicarboxyphenyl)ethane, bis(3,4-dicarboxyphenyl) phenyl)methane, bis(2,3-dicarboxyphenyl)methane, bis(3,4-dicarboxyphenyl)ether, 1,2,5,6-naphthalenetetracarboxylic acid, 9,9-bis(3,4-dicarboxyphenyl)fluorene, 9,9-bis{4-(3,4-dicarboxyphenoxy)phenyl}fluorene, 2,3,6,7-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 2,2-bis(3,Examples of suitable tetracarboxylic acids include, but are not limited to, 4-dicarboxyphenyl)hexafluoropropane, aromatic tetracarboxylic acids having the structures shown below, butane tetracarboxylic acid, cyclobutane tetracarboxylic acid, and 1,2,3,4-cyclopentane tetracarboxylic acid. Two or more of these may be used.

[0145]

[0146] In the formula, R １７ is an oxygen atom, C(CF ３ ) ２ , or C(CH ３ ) ２ Represents R １８ and R １９ represents a hydrogen atom or a hydroxyl group.

[0147] These acids can be used as they are, or as acid anhydrides, halides, or activated esters.

[0148] W-(R ２ ) ｂ , (OH) in the above general formula (2) ｄ -Y-(COOR ４ ) ｆ In the general formula (3), U represents a residue of a diamine. W, Y, and U are divalent to octavalent organic groups having 4 to 40 carbon atoms, and among these, organic groups having 4 to 40 carbon atoms and containing an aromatic ring or a cycloaliphatic group are preferred.

[0149] Specific examples of diamines constituting the diamine residue include hydroxyl group-containing diamines such as bis(3-amino-4-hydroxyphenyl)hexafluoropropane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)methylene, bis(3-amino-4-hydroxyphenyl)ether, bis(3-amino-4-hydroxy)biphenyl, and bis(3-amino-4-hydroxyphenyl)fluorene; 3-sulfonic acid-4,4'-diamine; sulfonic acid-containing diamines such as dimercaptophenylenediamine, thiol group-containing diamines such as dimercaptophenylenediamine, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 1,4-bis(4-aminophenoxy)benzene, benzine, m-phenylenediamine , p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(4-aminophenoxy)biphenyl, bis{4-(4-aminophenoxy)phenyl}ether, 1,4-bis(4-aminophenoxy)benzene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4' aromatic diamines such as 2,2'-diaminobiphenyl, 2,2',3,3'-tetramethyl-4,4'-diaminobiphenyl, 3,3',4,4'-tetramethyl-4,4'-diaminobiphenyl, and 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, and compounds in which some of the hydrogen atoms in the aromatic rings of these are substituted with alkyl groups or fluoroalkyl groups having 1 to 10 carbon atoms, halogen atoms, or the like; 2,4-diamino-1,3,5-triazine (guanamine), 2,4-diamino-6-methyl-1,3,5-triazine (acetoguanamine), 2,Examples of such diamines include diamines having a nitrogen-containing heteroaromatic ring, such as 4-diamino-6-phenyl-1,3,5-triazine (benzoguanamine); silicone diamines, such as 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(p-aminophenyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(p-aminophenethyl)-1,1,3,3-tetramethyldisiloxane, and 1,7-bis(p-aminophenyl)-1,1,3,3,5,5,7,7-octamethyltetrasiloxane; alicyclic diamines, such as cyclohexyldiamine and methylenebiscyclohexylamine; and diamines having the structures shown below. Two or more of these may be used.

[0150]

[0151] In the formula, R ２０ is an oxygen atom, C(CF ３ ) ２ , or C(CH ３ ) ２ Represents R ２１ ~R ２４ each independently represents a hydrogen atom or a hydroxyl group.

[0152] Among these, it is preferred to contain at least one diamine having the structure shown below from the viewpoint of improving the alkali developability and the transmittance of the (A) resin and its cured film.

[0153]

[0154] In the formula, R ２０ is an oxygen atom, C(CF ３ ) ２ , or C(CH ３ ) ２ Represents R ２１ ~R ２２ each independently represents a hydrogen atom or a hydroxyl group.

[0155] These diamines can be used as they are, or as diisocyanate compounds or trimethylsilylated diamines obtained by reacting the diamines with phosgene.

[0156] The resin (A) preferably contains a group selected from an alkylene group and an alkylene ether group. These groups may contain an aliphatic ring. As the group selected from the alkylene group and the alkylene ether group, a group represented by general formula (4) is particularly preferred.

[0157]

[0158] In general formula (4), R ５ ~R ８ R each independently represents an alkylene group having 1 to 6 carbon atoms. ９ ~R １６ each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 6 carbon atoms. However, the structures represented in the parentheses are different. g, h, and i each independently represent an integer of 0 to 35, and g + h + i > 0.

[0159] Examples of the group represented by formula (4) include an ethylene oxide group, a propylene oxide group, and a butylene oxide group, and the group may be linear, branched, or cyclic.

[0160] When the (A) resin contains a group selected from an alkylene group and an alkylene ether group, the mechanical properties, particularly the elongation, of the (A) resin and a cured film thereof can be improved, and the transmittance of light at 450 nm before and after curing can be further improved.

[0161] The (A) resin preferably contains a group selected from the alkylene group and the alkylene ether group as W in the general formula (1) or Y in the general formula (2), thereby improving the mechanical properties, particularly the elongation, of the (A) resin and a cured film thereof, and further improving the light transmittance at 450 nm before and after curing, and also achieving high chemical resistance due to the promotion of ring closure by low-temperature heat treatment in the cured film of the resin composition, high adhesion to the substrate metal, and resistance to the constant temperature and humidity test (HAST).

[0162] Specific examples of diamines containing a group selected from an alkylene group and an alkylene ether group include ethylenediamine, 1,3-diaminopropane, 2-methyl-1,3-propanediamine, 1,4-diaminobutane, 1,5-diaminopentane, 2-methyl-1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 1,2-bis(aminomethyl)cyclohexane, 1,3 -bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), KH-511, ED-600, ED-900, ED-2003, EDR-148, EDR-176, D-200, D- 400, D-2000, THF-100, THF-140, THF-170, RE-600, RE-900, RE-2000, RP-405, RP-409, RP-2005, RP-2009, RT-1000, HE-1000, HT-1100, HT-1700 (all trade names, manufactured by HUNTSMAN Co., Ltd.).

[0163] In addition, these diamines may contain -S-, -SO-, -SO ２ -, -NH-, -NCH ３ -, -N(CH ２ CH ３ ) -, -N(CH ２ CH ２ CH ３ )-,-N(CH(CH ３ ) ２ )-, -COO-, -CONH-, -OCONH-, -NHCONH-, and the like.

[0164] The diamine residues containing a group selected from an alkylene group and an alkylene ether group are preferably contained in an amount of 5 mol% or more, more preferably 10 mol% or more, of all diamine residues. Furthermore, the amount of the diamine residues is preferably 40 mol% or less, more preferably 30 mol% or less, of all diamine residues. By ensuring the amount is within the above range, the developability in an alkaline developer is improved, the mechanical properties, particularly the elongation, of the (A) resin and its cured film are improved, and the transmittance of light at 450 nm after curing can be improved. Furthermore, the cured film of the resin composition can be provided with high chemical resistance due to the promotion of ring closure by low-temperature heat treatment, high adhesion to metal surfaces, and resistance to constant temperature and humidity test (HAST).

[0165] Diamine residues having an aliphatic polysiloxane structure may be copolymerized within a range that does not reduce heat resistance. Copolymerization of diamine residues having an aliphatic polysiloxane structure can improve adhesion to substrates. Specific examples of diamine components include those obtained by copolymerizing 1 to 15 mol % of all diamine residues with bis(3-aminopropyl)tetramethyldisiloxane, bis(p-aminophenyl)octamethylpentasiloxane, or the like. Copolymerization within this range is preferred in terms of improving adhesion to substrates such as silicon wafers and not reducing solubility in alkaline solutions.

[0166] A resin having an acidic group at the end of the main chain can be obtained by capping the terminals of the (A) resin with a monoamine, acid anhydride, acid chloride, or monocarboxylic acid having an acidic group. Known monoamines, acid anhydrides, acid chlorides, and monocarboxylic acids having an acidic group may be used, or multiple monoamines, acid anhydrides, acid chlorides, and monocarboxylic acids may be used.

[0167] The content of the end-capping agent such as the monoamine, acid anhydride, acid chloride, or monocarboxylic acid is preferably 2 to 25 mol % relative to 100 mol % of the total of the acid components and amine components constituting the resin (A).

[0168] The (A) resin preferably has a weight-average molecular weight of 10,000 or more and 100,000 or less. If the weight-average molecular weight is 10,000 or more, the mechanical properties of the cured film after curing can be improved. More preferably, the weight-average molecular weight is 20,000 or more. On the other hand, if the weight-average molecular weight is 100,000 or less, the developability with various developers can be improved, and if the weight-average molecular weight is 50,000 or less, the developability with an alkaline solution can be improved, which is preferable.

[0169] The weight average molecular weight (Mw) can be determined using gel permeation chromatography (GPC). For example, it can be measured using N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP) as the developing solvent and calculated in terms of polystyrene.

[0170] The content of the (A) resin is preferably 3 to 55% by mass, and more preferably 5 to 40% by mass, of 100% by mass of all components including the solvent. By setting the content within this range, a viscosity appropriate for spin coating or slit coating can be achieved.

[0171] Other examples of resins that can be used include phenolic resins, polymers containing radically polymerizable monomers having alkali-soluble groups as monomer units, such as polyhydroxystyrene and acrylic, siloxane polymers, cyclic olefin polymers, and cardo resins. These resins may be used as known resins, and may be used alone or in combination.

[0172] From the viewpoint of reducing the transmittance, the phenol resin is preferably a wholly aromatic phenol resin made of a phenol compound and an aromatic aldehyde compound.

[0173] In the present invention, the resin composition containing the resin (A) preferably contains a photosensitizer (B) (hereinafter, sometimes referred to as component (B)).

[0174] It is preferable that the resin composition containing the resin (A) further contains a photosensitizer (B), since this imparts photosensitivity to the resin composition and enables the formation of a fine opening pattern.

[0175] The (B) photosensitizer is a compound whose chemical structure changes in response to ultraviolet light, and examples thereof include a photoacid generator, a photobase generator, a photopolymerization initiator, etc. When a photoacid generator is used as the (B) component, an acid is generated in the irradiated portion of the photosensitive resin composition, and the solubility of the irradiated portion in an alkaline developer increases, thereby making it possible to obtain a positive pattern in which the irradiated portion dissolves.

[0176] When (B) a photobase generator is contained as the photosensitizer, a base is generated in the irradiated parts of the resin composition, and the solubility of the irradiated parts in an alkaline developer decreases, so that a negative pattern can be obtained in which the irradiated parts are insolubilized.

[0177] When the resin composition contains a photopolymerization initiator (B) as a photosensitizer, radicals are generated in the irradiated area of ​​the resin composition, radical polymerization proceeds, and the resin composition becomes insoluble in an alkaline developer, thereby forming a negative pattern. In addition, UV curing during exposure is promoted, thereby improving sensitivity.

[0178] In the present invention, the cured film obtained by curing the resin composition containing (A) resin has a light transmittance of 0.1% or more and 95% or less at a wavelength of 450 nm at a thickness of 1 μm. This allows the cured film to have the high wiring concealment described above, thereby suppressing the glare of the wiring, making it difficult to see from the outside, and improving the design. If the light transmittance is less than 0.1%, there is a concern that problems such as a decrease in the sensitivity and resolution of the resin film before curing may occur. If the light transmittance exceeds 95%, there is a concern that the wiring concealment may decrease, the suppression of wiring glare may be insufficient, and problems such as the wiring being visible from the outside may occur.

[0179] In order to obtain such properties, the (B) photosensitizer is preferably one in which the (B) photosensitizer itself has low light transmittance at a wavelength of 450 nm and undergoes little structural change upon heat treatment, one in which the reaction product between the (B) photosensitizer and the (A) resin or thermal crosslinking agent or the like has low light transmittance, or one in which the decomposition product of the (B) photosensitizer itself or a reaction product derived from the decomposition product has low light transmittance.

[0180] From the viewpoint of microprocessability, the resin composition containing the resin (A) preferably has positive photosensitivity. Furthermore, the resin composition containing the resin (A) and the photosensitizer (B) preferably has positive photosensitivity.

[0181] Among the above-mentioned photosensitizers (B), photoacid generators are preferred from the viewpoints of high wiring hiding ability, high sensitivity, and fine processability. Examples of photoacid generators include quinone diazide compounds, sulfonium salts, phosphonium salts, diazonium salts, and iodonium salts. Furthermore, a sensitizer or the like may be contained as needed.

[0182] The quinone diazide compound is preferably a compound having a phenolic hydroxyl group and a naphthoquinone diazide sulfonic acid bonded to the compound via an ester bond. The compound having a phenolic hydroxyl group used here may be a known compound, and examples of the compound having a phenolic hydroxyl group to which 4-naphthoquinone diazide sulfonic acid or 5-naphthoquinone diazide sulfonic acid is introduced via an ester bond can be given as preferred examples, but other compounds can also be used.

[0183] In addition, it is preferable that 50 mol % or more of all functional groups of the compound having a phenolic hydroxyl group are substituted with quinone diazide. By using a quinone diazide compound substituted by 50 mol % or more, the affinity of the quinone diazide compound for alkaline aqueous solutions is reduced. As a result, the solubility of the unexposed portions of the resin composition in alkaline aqueous solutions is significantly reduced. Furthermore, the quinone diazide sulfonyl groups are converted to indene carboxylic acid by exposure, resulting in a high dissolution rate of the exposed portions of the photosensitive resin composition in alkaline aqueous solutions. That is, as a result, the dissolution rate ratio between the exposed and unexposed portions of the composition is increased, allowing for the production of patterns with high resolution.

[0184] By containing such a quinone diazide compound, it is possible to obtain a resin composition having positive photosensitivity that is sensitive to the i-line (365 nm), h-line (405 nm), and g-line (436 nm) of a general mercury lamp, or to a broad band including these. In addition, the (B) photosensitizer may be contained alone or in combination of two or more types, and a highly sensitive resin composition can be obtained.

[0185] Examples of quinone diazides include a 5-naphthoquinone diazide sulfonyl group, a 4-naphthoquinone diazide sulfonyl group, and those containing a 4-naphthoquinone diazide sulfonyl group and a 5-naphthoquinone diazide sulfonyl group in the same molecule.

[0186] Examples of naphthoquinone diazide sulfonyl ester compounds include 5-naphthoquinone diazide sulfonyl ester compound (B-1) and 4-naphthoquinone diazide sulfonyl ester compound (B-2). In the present invention, however, it is preferable to include compound (B-2). Compound (B-2) has high absorption in the i-line region of a mercury lamp, making it suitable for i-line exposure. Furthermore, compound (B-2) is preferable from the viewpoint of light transmittance after heat treatment, since coloration due to decomposition of compound (B-2) or reaction with resin (A) during curing can reduce the transmittance of light at 450 nm. When compound (B-2) is the sole component of the photosensitizer, or when compound (B-2) is mixed with other components, compound (B-2) is preferably contained in an amount of 46% by mass or more. When compound (B-1) and compound (B-2) are used as a mixture, compound (B-2) is preferably contained in an amount of 46% by mass or more but 100% by mass or less relative to the total amount of compound (B-1) and compound (B-2) used as the photosensitizer. By adjusting the content ratio within this range, a cured film having low light transmittance can be obtained.

[0187] The quinone diazide compound can be synthesized by a known method through an esterification reaction between a compound having a phenolic hydroxyl group and a quinone diazide sulfonic acid compound. The use of the quinone diazide compound further improves resolution, sensitivity, and film retention.

[0188] The molecular weight of the (B) photosensitizer is preferably 300 or more, more preferably 350 or more, and is preferably 3,000 or less, more preferably 1,500 or less, from the viewpoint of the heat resistance, mechanical properties, and adhesiveness of the film obtained by heat treatment.

[0189] Of the photosensitizers (B), sulfonium salts, phosphonium salts, and diazonium salts are preferred because they appropriately stabilize the acid component generated by exposure, with sulfonium salts being particularly preferred.

[0190] The content of the (B) photosensitizer is preferably 0.1 parts by mass or more and 100 parts by mass or less relative to 100 parts by mass of the (A) resin. When the content of the (B) photosensitizer is 0.1 parts by mass or more and 100 parts by mass or less, photosensitivity can be imparted while maintaining the heat resistance, chemical resistance, and mechanical properties of the film after heat treatment.

[0191] When the (B) photosensitizer contains a quinone diazide compound, the content of the (B) photosensitizer is preferably 1 part by mass or more, and even more preferably 3 parts by mass or more, per 100 parts by mass of the (A) component. Also, the content is more preferably 100 parts by mass or less, and even more preferably 80 parts by mass or less. When the content is 1 part by mass or more and 100 parts by mass or less, photosensitivity can be imparted while maintaining the heat resistance, chemical resistance, and mechanical properties of the film after heat treatment.

[0192] When the (B) photosensitizer contains a sulfonium salt, a phosphonium salt, or a diazonium salt, the content of the (B) photosensitizer is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and particularly preferably 3 parts by mass or more, relative to 100 parts by mass of the (A) resin. Also, it is more preferably 100 parts by mass or less, more preferably 80 parts by mass or less, and particularly preferably 50 parts by mass or less. If it is 0.1 parts by mass or more and 100 parts by mass or less, it is possible to impart photosensitivity while maintaining the heat resistance, chemical resistance, and mechanical properties of the film after heat treatment.

[0193] When a photobase generator is contained as the photosensitizer (B), specific examples of the photobase generator include amide compounds and ammonium salts.

[0194] Examples of the amide compound include 2-nitrophenylmethyl-4-methacryloyloxypiperidine-1-carboxylate, 9-anthrylmethyl-N,N-dimethylcarbamate, 1-(anthraquinone-2yl)ethylimidazolecarboxylate, and (E)-1-[3-(2-hydroxyphenyl)-2-propenoyl]piperidine.

[0195] Examples of ammonium salts include 1,2-diisopropyl-3-(bisdimethylamino)methylene)guanidinium 2-(3-benzoylphenyl)propionate, (Z)-{[bis(dimethylamino)methylidene]amino}-N-cyclohexylamino)methaniminium tetrakis(3-fluorophenyl)borate, and 1,2-dicyclohexyl-4,4,5,5-tetramethylbiguanidinium n-butyltriphenylborate.

[0196] When a photobase generator is contained as the (B) photosensitizer, the content of the (B) photosensitizer in the resin composition is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 0.7 parts by mass or more, and particularly preferably 1 part by mass or more, relative to 100 parts by mass of the (A) resin. When the content is within the above range, the sensitivity during exposure can be improved. On the other hand, the content is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, even more preferably 17 parts by mass or less, and particularly preferably 15 parts by mass or less. When the content is within the above range, the resolution after development can be improved.

[0197] When a photopolymerization initiator is contained as the (B) photosensitizer, preferred examples of the photopolymerization initiator include benzyl ketal-based photopolymerization initiators, α-hydroxyketone-based photopolymerization initiators, α-aminoketone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, oxime ester-based photopolymerization initiators, acridine-based photopolymerization initiators, benzophenone-based photopolymerization initiators, acetophenone-based photopolymerization initiators, aromatic ketoester-based photopolymerization initiators or benzoate ester-based photopolymerization initiators, and titanocene-based photopolymerization initiators. Known photopolymerization initiators may be used, or a plurality of such initiators may be used. Among these, from the viewpoint of improving sensitivity during exposure, an α-hydroxyketone-based photopolymerization initiator, an α-aminoketone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, an oxime ester-based photopolymerization initiator, an acridine-based photopolymerization initiator, or a benzophenone-based photopolymerization initiator is more preferable, and an α-aminoketone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, or an oxime ester-based photopolymerization initiator is even more preferable.

[0198] When a photopolymerization initiator (B) is contained as the photosensitizer, the content of the photosensitizer (B) in the resin composition is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 0.7 parts by mass or more, and particularly preferably 1 part by mass or more, relative to 100 parts by mass of the resin (A). When the content is within the above range, the sensitivity during exposure can be improved. On the other hand, the content is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, even more preferably 17 parts by mass or less, and particularly preferably 15 parts by mass or less. When the content is within the above range, the resolution after development can be improved.

[0199] In the present invention, it is preferable that the resin composition containing the resin (A) further contains a colorant (C), and that the colorant (C) contains a colorant (C-1) having an absorption maximum in a wavelength range of 400 nm or more and 490 nm or less (hereinafter, these may be referred to as the component (C) or the component (C-1)).

[0200] Examples of the colorant (C) include a thermochromic compound, a dye, a pigment, etc. Among these, from the viewpoints of heat resistance, sensitivity, and resolution, it is preferable to use one or more of either a dye or an organic pigment, and a dye is more preferable.

[0201] When the component (C) contains the component (C-1), the component (C) absorbs light in the wavelength range of 400 nm or more and 490 nm or less, thereby reducing the amount of transmitted light, and the transmittance of light with a wavelength of 450 nm at a standard thickness of 1 μm in the cured film according to the present invention can be made 0.1% or more and 95% or less. The cured film has high wiring concealment properties, which reduces glare from the wiring, making it difficult to see from the outside, and improving the design properties.

[0202] Preferably, the component (C-1) is a colorant having an absorption maximum in the wavelength range of 420 nm or more and 480 nm or less, more preferably in the wavelength range of 430 nm or more and 470 nm or less.

[0203] The component (C-1) has the property of transmitting light with a wavelength of 350 nm to 390 nm, which is a part of the exposure wavelength, so that both sensitivity and resolution to the exposure wavelength can be achieved. －５In the compound solution of 100 mol / L, the transmittance of light with a wavelength of 350 nm to 390 nm is preferably 40% or more, and more preferably 70% or more.

[0204] It is sufficient that at least one type of component (C-1) is contained. Examples of the component (C-1) include a method using one type of thermochromic compound, one type of dye, or one type of organic pigment, a method using a mixture of two or more types of thermochromic compounds, dyes, or organic pigments, and a method using a combination of one or more types of thermochromic compounds, one or more types of dyes, and one or more types of organic pigments.

[0205] Examples of the component (C-1) include yellow dyes, orange dyes, etc. Examples of the type of dye include oil-soluble dyes, disperse dyes, reactive dyes, acid dyes, and direct dyes.

[0206] Examples of the skeleton structure of the dye used as component (C-1) include, but are not limited to, anthraquinones, methines, quinolines, perinones, etc. These dyes may be used alone or as metal-containing complex salts. Specifically, Sumilan and Lanyl dyes (manufactured by Sumitomo Chemical Co., Ltd.), Orasol, Oracet, Filamid, and Irgasperse dyes (manufactured by Ciba Specialty Chemicals Co., Ltd.), Zapon, Neozapon, Neptune, and Acidol dyes (manufactured by BASF Corporation), Kayaset and Kayakalan dyes (manufactured by Nippon Kayaku Co., Ltd.), Valifast Colors dyes (manufactured by Orient Chemical Industry Co., Ltd.), Savinyl, Sandoplast, Polysynthren, and Lanasyn dyes (manufactured by Clariant Japan Co., Ltd.), Aizen Spilon dyes (manufactured by Hodogaya Chemical Co., Ltd.), functional dyes (manufactured by Yamada Chemical Co., Ltd.), and Plast Color dyes, Oil Color dyes (manufactured by Arimoto Chemical Industry Co., Ltd.), etc. can be used, but are not limited thereto. These dyes can be used alone or in combination.

[0207] The pigment used as component (C-1) is preferably a pigment with high heat resistance from the viewpoint of preventing discoloration during curing. Specific examples, expressed by Color Index (CI) numbers, include yellow pigments such as Pigment Yellow 83, 117, 129, 138, 139, 150, and 180. Examples of orange pigments include Pigment Orange 38, 43, 64, 71, and 72. The content of component (C-1) is preferably 0.1 to 100 parts by mass, more preferably 0.2 to 50 parts by mass, per 100 parts by mass of resin (A). By ensuring that the content of component (C-1) is 0.1 parts by mass or more, it is possible to absorb light of the corresponding wavelength. By ensuring that the content is 100 parts by mass or less, it is possible to achieve both high light transmittance, sensitivity, and resolution.

[0208] In the present invention, it is preferable that the resin composition containing the (A) resin further contains a (C) colorant, and that the (C) colorant contains (C-2) a colorant having an absorption maximum in the wavelength range of more than 490 nm to 580 nm (hereinafter, this may be referred to as the (C-2) component).

[0209] In the present invention, it is preferable that the resin composition containing the (A) resin further contains a (C) colorant, and that the (C) colorant contains (C-3) a colorant having an absorption maximum in the wavelength range of more than 580 nm to 800 nm (hereinafter, this may be referred to as a (C-3) component).

[0210] In the present invention, it is also preferred that the component (C) further contains, in addition to the component (C-1), (C-2) a colorant having an absorption maximum in the wavelength range of more than 490 nm to 580 nm, and (C-3) a colorant having an absorption maximum in the wavelength range of more than 580 nm to 800 nm.

[0211] In addition to the (C-1) component, by containing the (C-2) component and the (C-3) component, in addition to the wiring concealment property, the blackening reduces external light reflection and improves contrast, thereby improving visibility, which is preferable. The (C-2) and (C-3) components, like the (C-1) component, preferably have high solvent solubility, heat resistance, and transmittance at wavelengths of 350 nm to 390 nm, and it is preferable to use one or more of dyes and organic pigments, with dyes being more preferable. This is preferable because, in addition to blackening by mixing the (C-1) component with the (C-2) component and the (C-3) component, it is possible to achieve high sensitivity and high resolution in the resin film, which is also preferable.

[0212] Examples of the skeleton structure of dyes that can be preferably used as components (C-2) and (C-3) include, but are not limited to, triphenylmethane-based dyes, anthraquinone-based dyes, etc. These dyes may be used alone or as metal-containing complex salts. Specifically, Sumilan and Lanyl dyes (manufactured by Sumitomo Chemical Co., Ltd.), Orasol, Oracet, Filamid, and Irgasperse dyes (manufactured by Ciba Specialty Chemicals Co., Ltd.), Zapon, Neozapon, Neptune, and Acidol dyes (manufactured by BASF Corporation), Kayaset and Kayakalan dyes (manufactured by Nippon Kayaku Co., Ltd.), Valifast Colors dyes (manufactured by Orient Chemical Industry Co., Ltd.), Savinyl, Sandoplast, Polysynthren, and Lanasyn dyes (manufactured by Clariant Japan Co., Ltd.), Aizen Spilon dyes (manufactured by Hodogaya Chemical Co., Ltd.), functional dyes (manufactured by Yamada Chemical Co., Ltd.), and Plast Color dyes, Oil Color dyes (manufactured by Arimoto Chemical Industry Co., Ltd.), etc. can be used, but are not limited thereto. These dyes can be used alone or in combination.

[0213] Specific examples of organic pigments that can be preferably used as component (C-2) are shown by Color Index (CI) number. Examples of red pigments include Pigment Red 48:1, 122, 168, 177, 202, 206, 207, 209, 224, 242, and 254. Examples of purple pigments that can be preferably used as component (C-2) include Pigment Violet 19, 23, 29, 32, 33, 36, 37, and 38. Examples of blue pigments that can be preferably used as component (C-3) include Pigment Blue 15 (15:3, 15:4, 15:6, etc.), 21, 22, 60, and 64. Examples of green pigments that can be preferably used as component C-3 include Pigment Green 7, 10, 36, 47, and 58. Pigments other than these can also be used. Similarly to the above, pigments that have been subjected to a surface treatment may be used if necessary.

[0214] The contents of the (C-2) and (C-3) components are each preferably 0.1 to 100 parts by mass, and more preferably 0.2 to 50 parts by mass, per 100 parts by mass of the (A) resin. By making the content of the (C-1) component 0.1 parts by mass or more, it is possible to absorb light of the corresponding wavelength. Furthermore, by making the content 100 parts by mass or less, it is possible to achieve both light transmittance, sensitivity, and resolution.

[0215] Furthermore, from the viewpoints of storage stability and color fading during curing, the dyes used as the components (C-1), (C-2), and (C-3) are preferably dyes that are soluble in an organic solvent that dissolves the resin (A), are compatible with the resin, and have high heat resistance. Examples of the organic solvent include polar aprotic solvents such as N-methyl-2-pyrrolidone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropyleneurea, N,N-dimethylisobutyric acid amide, and methoxy-N,N-dimethylpropionamide; ethers such as tetrahydrofuran, dioxane, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, and diisobutyl ketone; esters such as ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, propylene glycol monomethyl ether acetate, and 3-methyl-3-methoxybutyl acetate; alcohols such as ethyl lactate, methyl lactate, diacetone alcohol, and 3-methyl-3-methoxybutanol; and aromatic hydrocarbons such as toluene and xylene. As for heat resistance, it is preferable that no change in absorption spectrum is observed before and after heating at 250° C. for 1 hour in an atmosphere with an oxygen concentration of 100 ppm or less.

[0216] The organic pigment may be surface-treated, such as by rosin treatment, acidic group treatment, or basic group treatment, as needed. In addition, the organic pigment may be used in combination with a dispersant, if necessary. Examples of dispersants include cationic, anionic, nonionic, amphoteric, silicone, and fluorine-based surfactants.

[0217] In the present invention, it is preferable that the resin composition containing the (A) resin further contains a (C) colorant, and the (C) colorant contains a (C-4) black colorant (hereinafter, sometimes referred to as a (C-4) component).

[0218] When the component (C) contains the component (C-4), the transmittance of light with a wavelength of 450 nm at a standard thickness of 1 μm in the cured film according to the present invention can be 0.1% or more and 95% or less. The cured film has high wiring concealment properties, which suppresses glare from the wiring, making it difficult to see from the outside and improving design properties. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0219] It is sufficient that at least one type of component (C-4) is contained. Examples include a method using one type of inorganic black pigment, organic black pigment, or black dye, and a method using a combination of two or more types of inorganic black pigments, organic black pigments, or black dyes.

[0220] Examples of inorganic black pigments include, but are not limited to, inorganic black pigments containing titanium atoms, inorganic black pigments containing zirconium atoms, amorphous carbon black, and carbon black. Amorphous carbon black, as used herein, refers to non-crystalline carbon black particles. Meanwhile, simply referring to carbon black, refers to crystalline carbon black particles that are generally well known for use as a colorant.

[0221] The inorganic black pigment containing titanium atoms refers to one or more of titanium nitride represented by TiN, titanium oxynitride represented by TiNxOy (0<x<2.0, 0.1<y<2.0), titanium carbide represented by TiC, a solid solution of titanium nitride and titanium carbide, and a composite oxide or composite nitride of titanium and a metal other than titanium. Among these, titanium nitride and titanium oxynitride are preferred because they have high light-shielding properties in the visible light range and high transmittance of exposure light in the exposure step, and titanium nitride is more preferred because of its low dielectric constant. Titanium nitride can be produced by gas-phase reactions, and titanium nitride synthesized by a thermal plasma method is preferred because it is easy to obtain particles with a small primary particle size and a sharp particle size distribution. Furthermore, inorganic black pigments containing titanium atoms contain inorganic white pigments such as TiO as impurities to avoid an increase in the dielectric constant. ２ The smaller the content of titanium dioxide represented by the formula (I) is, the better, and it is more preferable that the titanium dioxide is not contained at all.

[0222] The inorganic black pigment having zirconium atoms is Zr ３ N ４ The term "zirconium nitride" refers to one or more of zirconium nitride represented by the formula (I), zirconium nitride represented by ZrN, zirconium oxynitride represented by ZrOxNy (0<x<2.0, 0.1<y<2.0), and composite oxides or composite nitrides of zirconium and metals other than zirconium. Among these, zirconium nitride represented by ZrN is preferred because it has a high transmittance to exposure light in the exposure step and a low dielectric constant. Examples of production methods include gas phase reactions, and among these, zirconium nitride synthesized by a thermal plasma method is preferred because it is easy to obtain particles with a small primary particle diameter and a sharp particle size distribution. Furthermore, inorganic black pigments containing zirconium atoms contain inorganic white pigments such as ZrO as impurities to avoid an increase in the dielectric constant. ２ The smaller the content of zirconium dioxide represented by the formula (I) is, the more preferable, and it is more preferable that the zirconium dioxide is not contained at all.

[0223] The inorganic black pigment having a titanium atom and the inorganic black pigment having a zirconium atom may be subjected to a surface treatment to modify the pigment surface, if necessary. Examples of surface treatment methods include a method of introducing an organic group containing a silicon atom as a surface modification group through treatment with a silane coupling agent, and a method of coating part or all of the pigment surface with a coating material such as silica, a metal oxide, and / or an organic resin. Multiple surface treatments may be combined. By applying these surface treatments, the long-term storage stability of the resin composition of the present invention may be improved. The inorganic black pigment having a zirconium atom and the inorganic black pigment having a titanium atom may form a single primary particle as a solid solution containing both.

[0224] Amorphous carbon black is a material with a diamond structure (SP ３ structure) and graphite structure (SP ２This refers to amorphous carbon black consisting of an SP structure. It corresponds to carbon classified as diamond-like carbon (DLC). Amorphous carbon black has higher insulating properties than crystalline carbon black, which will be described later, and can be suitably used as a colorant without surface treatment. A preferred method for producing amorphous carbon black is to vaporize a carbon source, cool the vaporized carbon vapor, resolidify it, turn it into flakes, and then dry-pulverize it to make fine particles. The structure of amorphous carbon black is SP ３ When the SP structure is contained in a large amount, the light blocking ability for visible light and near infrared rays is low, but the insulating property can be improved. ２ When the photosensitive composition of the present invention contains a large number of SP structures, the insulating properties are low, but the light-shielding properties of visible light and near-infrared rays can be improved. In other words, the properties inherent to the pigment can be controlled by adjusting the synthesis conditions. ３ Structure and SP ２ For the total structure, SP ３ Amorphous carbon black having a structure content of 30 to 70 atom % can be preferably used. ３ Structure and SP ２ The proportions of the structure can be analyzed by X-ray photoelectron spectroscopy.

[0225] The total amount of the above inorganic black pigment having titanium atoms, inorganic black pigment having zirconia atoms, and amorphous carbon is preferably 5.0 mass% or more of the total solid content of the photosensitive composition in the present invention in order to further improve the near-infrared ray blocking properties. Furthermore, in order to avoid an excessive increase in the dielectric constant, the total amount is preferably 35.0 mass% or less of the total solid content of the photosensitive composition. The total solid content here refers to the components of the photosensitive composition excluding the solvent.

[0226] Carbon blacks are classified according to their production method, and include furnace black, thermal black, channel black, acetylene black, ketjen black, and lamp black. Of these, furnace black produced by the furnace method is preferred because it has excellent dispersibility and allows industrially easy control of the acidity of the pigment surface and the particle size. Among these, from the viewpoint of improving insulation, the shorter the length of the structure in which the particles are tightly linked like beads, which is characteristic of carbon black, the more preferable. Furthermore, carbon blacks surface-modified with organic groups or coated with highly insulating coating materials are more preferred. Such surface-modified carbon blacks may be commercially available, and examples thereof include "TPK-1227," a carbon black surface-modified with an acidic functional group containing a sulfur atom, and "TPX-1409," a carbon black whose pigment surface is coated with silica (both manufactured by CABOT Corporation).

[0227] The total amount of carbon black is preferably 5.0% by mass or more of the total solid content of the resin composition in the present invention in order to further improve the near-infrared ray shielding property, and is preferably 10.0% by mass or less of the total solid content of the resin composition in order to avoid an excessive increase in the dielectric constant.

[0228] A mixture of multiple materials may be used so that the cured film has the desired optical properties. For example, by using zirconium nitride, which exhibits a black color with a strong purplish tint, and amorphous carbon, which exhibits a black color with a strong yellowish tint, to achieve a color tone, the reflected color of the cured film can be made neutral black with low saturation.

[0229] The average primary particle size of the inorganic black pigment is preferably 5 nm or more, more preferably 10 nm or more, from the viewpoint of improving dispersibility and storage stability after dispersion. On the other hand, from the viewpoint of obtaining high flexibility, it is preferably 150 nm or less, more preferably 100 nm or less. The average primary particle size referred to here means the number average value of primary particle diameters calculated by a particle size measurement method using an image analysis particle size distribution analyzer. A transmission electron microscope (TEM) can be used to capture images, and the average primary particle size can be calculated at a magnification of 50,000 times. When component (C-4) is not spherical, the average value of its major and minor axes is taken as the primary particle size. For image analysis, the image analysis particle size distribution software Mac-View manufactured by Mountech Co., Ltd. is used. When it is necessary to reduce the average primary particle size or to grind coarse particles to achieve a sharp particle size distribution, dry milling may be performed. For dry milling, for example, a hammer mill or a ball mill can be used. Furthermore, when there is a limit to what can be achieved by dry pulverization due to reasons such as excessively high hardness of the pigment, it is desirable to remove the coarse particles by classification without crushing.

[0230] Organic black pigments include benzodifuranone-based black pigments, perylene-based black pigments, azo-based black pigments, and their isomers. The term "isomers" here also includes tautomers. The isomers may be contained as a mixture of multiple pigment powders, or may be contained as mixed crystals constituting a single primary particle. Generally, organic pigments have very poor light-blocking properties in the near-infrared region, but have the advantage of a low dielectric constant. Therefore, in the resin composition containing the (A) resin of the present invention, organic pigments can be effectively used as a component that imparts light-blocking properties only in the visible light region while avoiding an increase in dielectric constant.

[0231] Examples of benzodifuranone-based black pigments include, but are not limited to, "Irgaphor (registered trademark)" Black S0100 manufactured by BASF. ３ H, SO ３ The dispersibility can be improved by partially mixing a benzodifuranone-based black pigment having a substituent such as - or COOH as a dispersing aid and carrying out a wet dispersion treatment.

[0232] Examples of perylene-based black pigments, in terms of Color Index (CI) numbers, include C.I. Pigment Black 31 and 32, such as FK4280 manufactured by BASF, but are not limited thereto.

[0233] The resin composition containing the resin (A) of the present invention may further contain a dispersant. A dispersant refers to a compound having both a pigment-affinity group that chemically bonds to or adsorbs to the pigment surface and a polymer chain or group that is solvent-philic. The mechanism of action of a dispersant involves a combination of acid-base interactions, hydrogen bonding, van der Waals forces, and other factors. In the wet media dispersion process performed to prepare the pigment dispersion described below, the dispersant enhances the wettability of the organic pigment surface to the dispersion medium and enhances the steric and / or electrostatic repulsion between the organic pigments due to the polymer chains, thereby promoting pigment micro-particle size reduction and improving dispersion stability. This promotion of micro-particle size reduction and improved dispersion stability can further improve flexibility.

[0234] Dispersants having a basic adsorptive group, dispersants having an acidic group, and nonionic dispersants can be preferably used. Examples of dispersants having a basic adsorptive group include DisperBYK-142, 145, 164, 167, 182, 187, 2001, 2008, 2009, 2010, 2013, 2020, 2025, 9076, 9077, BYK-LP N6919, and BYK-LP N21116, BYK-JET9152 (all manufactured by BYK-Chemie), "Solsperse (registered trademark)" 9000, 11200, 13650, 20000, 24000, 24000SC, 24000GR, 32000, 32500, 32550, 326000, 33000, 34750, 35100, 35200, 37500, 39000, 56000, 76500 (all manufactured by Lubrizol Corporation), Efka-PX4310, 4320, 4710 (all manufactured by BASF Corporation). Examples of dispersants having an acidic group include Tego disperses (registered trademark) 655 (manufactured by Evonik) and DisperBYK-102, 118, 174, and 2096 (all manufactured by BYK-Chemie). Examples of nonionic dispersants include SOLSPERSE (registered trademark) 54000 (manufactured by Lubrizol) and Tego disperses (registered trademark) 650, 652, and 740W (all manufactured by Evonik). Taking into consideration the surface properties and average primary particle size specific to the pigment, these dispersants may be used alone or in combination as appropriate so as to obtain the average dispersed particle size described below.

[0235] The content of the dispersant is preferably 10 parts by mass or more, and more preferably 20 parts by mass or more, per 100 parts by mass of the total amount of pigment, in order to achieve sufficient deaggregation in the wet media dispersion treatment described below and to suppress reagglomeration after the dispersion treatment. On the other hand, in order to ensure a sufficient content of components other than the dispersant, the content is preferably 100 parts by mass or less, and more preferably 60 parts by mass or less.

[0236] The resin composition containing the (A) resin may contain, as necessary, other components such as a thermal crosslinking agent, a radically polymerizable compound, an antioxidant, a solvent, a compound having a phenolic hydroxyl group, an adhesion improver, an adhesion promoter, or a surfactant.

[0237] Next, a method for producing the resin composition of the present invention will be described. For example, the resin composition can be obtained by mixing and dissolving the resin (A) and, if necessary, the photosensitizer (B), the colorant (C), the thermal crosslinking agent, the radical polymerizable compound, the antioxidant, the solvent, the compound having a phenolic hydroxyl group, the adhesion improver, the adhesiveness improver, the surfactant, and the like.

[0238] The dissolution method may be a known method such as heating or stirring.

[0239] The viscosity of the resin composition is preferably 2 to 5,000 mPa·s. By adjusting the solid content concentration so that the viscosity is 2 mPa·s or more, it is easy to obtain a desired film thickness. On the other hand, if the viscosity is 5,000 mPa·s or less, it is easy to obtain a highly uniform resin film. A resin composition having such a viscosity can be easily obtained, for example, by adjusting the solid content concentration to 5 to 60 mass%. Here, the solid content concentration refers to the components other than the solvent.

[0240] The resulting resin composition is preferably filtered using a filter to remove dust and particles. Filter materials include polypropylene (PP), polyethylene (PE), nylon (NY), and polytetrafluoroethylene (PTFE), with polyethylene and nylon being preferred.

[0241] When forming a cured film by curing a resin composition containing the (A) resin, a resin sheet may be formed from the resin composition containing the (A) resin, and then the resin sheet may be cured to form a film.

[0242] The resin sheet refers to a sheet formed on a substrate using the resin composition, specifically, a resin sheet obtained by applying the resin composition to a substrate and drying it.

[0243] A film such as polyethylene terephthalate (PET) can be used as the substrate to which the resin composition is applied. When the resin sheet is used by being attached to a substrate such as a silicon wafer, if it is necessary to peel and remove the substrate, it is preferable to use a substrate whose surface is coated with a release agent such as a silicone resin, because this allows the resin sheet to be easily peeled from the substrate.

[0244] Next, a method for manufacturing the display device will be described.

[0245] The method for manufacturing a display device of the present invention is a method for manufacturing a display device having at least wiring, a cured film, and light-emitting elements each having electrodes on two different surfaces, and includes the steps of: (D1) arranging the light-emitting elements on a supporting substrate; (D2) forming a resin film made of a resin composition containing a resin (A) on the supporting substrate and the light-emitting elements; (D3) exposing and developing the resin film to form a pattern of a plurality of through-holes in the resin film; (D6) curing the resin film to form the cured film having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm; and (D5) forming the wiring on at least a portion of the surface of the cured film and in the opening pattern of the cured film.

[0246] FIG. 7 shows a cross-sectional view taken along a plane perpendicular to a supporting substrate, illustrating a manufacturing process of an example of a display device having a plurality of light-emitting elements according to the present invention.

[0247] Hereinafter, the term "resin film" refers to a film obtained by applying a resin composition containing (A) resin to a substrate or laminating a resin sheet thereon and drying it. Here, a resin composition containing (A) resin that contains a solvent may also be referred to as a "varnish." Furthermore, the term "cured film" refers to a resin film or a film obtained by curing a resin sheet.

[0248] In FIG. 7a, step (D1) is a step of disposing a light-emitting element 2 having electrodes 6 on two different surfaces on a support substrate 18. The support substrate may be, but is not limited to, a glass substrate, a silicon substrate, a ceramic substrate, gallium arsenide, an organic circuit substrate, an inorganic circuit substrate, or a substrate having a circuit component disposed thereon. A temporary bonding material or wiring 4d may be disposed on the support substrate. A TFT array substrate may also be used. The support substrate may be used as a counter substrate or a light-emitting element driving substrate, or may be removed during the process. After removal, a different counter substrate or light-emitting element driving substrate may be disposed. FIG. 7a illustrates an example in which a temporary bonding layer is formed on the support substrate 18 and wiring 4d is formed thereon. The electrode 6 and wiring 4d may be connected via a bump, a conductive film, or the like, or may be directly connected. Furthermore, the wiring 4d may be connected to wiring 4 extending through a cured film 3 arranged so as to contact at least a portion of the light-emitting element 2 via a through-electrode or the like, or may be connected to the light-emitting element driving substrate 7.

[0249] Next, step (D2) is a step of forming a resin film 19 by applying or laminating a resin composition containing (A) resin or a resin sheet formed from a resin composition containing (A) resin onto the support substrate 18 and the light-emitting element 2, as shown in Figure 7b.

[0250] Note that "on the support substrate and on the light-emitting element" does not only refer to the surface of the support substrate or the surface of the light-emitting element, but also to the upper side of the support substrate or the light-emitting element, and a resin film may be formed by applying or laminating a resin composition containing the (A) resin or a resin sheet formed from a resin composition containing the (A) resin onto a cured film, wiring, or partition wall.

[0251] Examples of the coating method include spin coating, slit coating, dip coating, spray coating, printing, etc. The coating thickness varies depending on the coating method, the solids concentration of the composition, the viscosity, etc., but the coating is usually carried out so that the film thickness after drying will be 0.1 to 150 μm.

[0252] Prior to coating, the support substrate to which the resin composition containing the resin (A) is to be applied may be pretreated with the adhesion promoter described above. For example, the substrate surface may be treated by spin coating, slit die coating, bar coating, dip coating, spray coating, steam treatment, or the like using a solution in which 0.5 to 20% by mass of the adhesion promoter is dissolved in a solvent such as isopropanol, ethanol, methanol, water, tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, or diethyl adipate. After the substrate surface treatment, a reduced pressure drying treatment may be performed as necessary. Furthermore, the reaction between the substrate and the adhesion promoter may then be promoted by heat treatment at 50°C to 280°C.

[0253] Next, the coated film of the resin composition containing the (A) resin is dried to obtain the resin film 19. Drying is preferably carried out using an oven, a hot plate, infrared rays, or the like at a temperature in the range of 50°C to 140°C for 1 minute to several hours.

[0254] On the other hand, when the resin sheet is used, if the resin sheet has a protective film, the protective film is peeled off, and the resin sheet and a support substrate are placed opposite each other and bonded together by thermocompression (placing the resin sheet and the support substrate opposite each other and bonding them together by thermocompression is sometimes referred to as laminating the resin sheet to the support substrate). Next, the resin sheet laminated to the support substrate is dried in the same manner as when obtaining the resin film, to form resin film 19. The resin sheet can be obtained by applying a resin composition containing resin (A) to a support film made of polyethylene terephthalate or the like, which is a peelable substrate, and drying it.

[0255] Thermocompression bonding can be performed by heat pressing, heat lamination, thermal vacuum lamination, etc. The lamination temperature is preferably 40°C or higher in terms of adhesion to the substrate and embeddability. Furthermore, when the resin sheet is photosensitive, the lamination temperature is preferably 140°C or lower to prevent the resin sheet from curing during lamination, which would reduce the resolution of pattern formation in the exposure and development steps.

[0256] Next, in step (D3), a penetrating opening pattern 12 corresponding to the shape of the wiring 4 is formed in the resin film 19 by photolithography, as shown in FIG. 7c.

[0257] (A) A resin composition or a resin sheet containing the resin can be microfabricated, allowing light-emitting elements to be arranged at high density.

[0258] The photosensitive resin film is irradiated with actinic radiation through a mask having a desired pattern. Actinic radiation used for exposure includes ultraviolet light, visible light, electron beams, X-rays, etc., but in the present invention, it is preferable to use g-rays (436 nm), h-rays (405 nm), or i-rays (365 nm), which are common exposure wavelengths. For non-photosensitive resin films, a photoresist is formed after the resin film is formed, and then the actinic radiation is irradiated.

[0259] The exposed photosensitive resin film 19 is developed. The developer is preferably an aqueous solution of an alkaline compound such as tetramethylammonium, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, dimethylaminoethyl acetate, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, or hexamethylenediamine. In some cases, these alkaline aqueous solutions may contain one or more polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, γ-butyrolactone, or dimethylacrylamide; alcohols such as methanol, ethanol, or isopropanol; esters such as ethyl lactate or propylene glycol monomethyl ether acetate; or ketones such as cyclopentanone, cyclohexanone, isobutyl ketone, or methyl isobutyl ketone. After development, the film is typically rinsed with water. Here too, rinsing treatment may be carried out by adding alcohols such as ethanol and isopropyl alcohol, or esters such as ethyl lactate and propylene glycol monomethyl ether acetate to water.

[0260] Next, in step (D6), the resin film 19 shown in FIG. 7c is cured to form a cured film 3 having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 5 μm.

[0261] In addition, step (D6) may be step (D4) of curing resin film 19 to form cured film 3 having a transmittance of 0.1% or more and 79% or less for light with a wavelength of 450 nm at a thickness of 5 μm, or step (D7) of curing resin film 19 to form cured film 3 having a transmittance of 0.1% or more and 25% or less for light with a wavelength of 450 nm at a thickness of 1 μm.

[0262] The resin film 19 is heated to promote a ring-closing reaction or a thermal crosslinking reaction, yielding a cured film 3. The cured film 3 has improved heat resistance and chemical resistance due to crosslinking between (A) resins or (B) photosensitizers, thermal crosslinkers, and the like. This heat treatment may be performed by gradually increasing the temperature or by continuously increasing the temperature. The heat treatment is preferably performed for 5 minutes to 5 hours. An example includes a 30-minute heat treatment at 110°C, followed by a further 60-minute heat treatment at 230°C. Heat treatment conditions are preferably 140°C or higher and 400°C or lower. To promote the thermal crosslinking reaction, a heat treatment temperature of 140°C or higher is preferred, and 160°C or higher is more preferred. Furthermore, to provide an excellent cured film and improve the reliability of display devices, heat treatment conditions are preferably 300°C or lower, and more preferably 250°C or lower.

[0263] The heating may be carried out in an air atmosphere, or in order to prevent discoloration of component (C), in an atmosphere with a low oxygen concentration, preferably 1000 ppm or less, more preferably 300 ppm or less, even more preferably 100 ppm or less, and particularly preferably 50 ppm or less.

[0264] The cured film thus obtained has an opening pattern, and the angle of the inclined side in the cross section of the opening pattern is preferably 40° or more and 85° or less. When the angle of the cross-sectional shape of the opening is 40° or more, multiple light-emitting elements can be arranged efficiently, enabling high definition. The angle of the cross-sectional shape of the opening is more preferably 50° or more. On the other hand, when the angle of the cross-sectional shape of the opening is 85° or less, wiring defects such as wiring short circuits can be suppressed. The angle of the cross-sectional shape of the opening is more preferably 80° or less.

[0265] Fig. 16 shows a cross-sectional view of the opening pattern of the cured film taken along a plane perpendicular to the support base. In Fig. 16, the angle of the inclined side 26 of the opening pattern formed in the cured film 3 is 27. The inclined side is a straight line connecting the opening pattern at a position 29 that is halfway along the thickness direction of the cured film 3 and the opening pattern at the bottom.

[0266] Next, in FIG. 7c, in order to improve the adhesion between the hardened film 3 and the wiring 4, a barrier metal such as titanium is sputtered on the hardened film 3, and a copper seed (seed layer) is further formed on top of that by sputtering.

[0267] 7d, in step (D5), after forming a photoresist layer (not shown), wiring 4 made of a metal such as copper or a conductive film for electrically connecting to at least one electrode 6 of the light-emitting element 2 is formed on the opening pattern 12 of the cured film 3 and on a part of the surface of the cured film 3 by plating, sputtering, processing a photosensitive conductive paste, etc. Then, unnecessary photoresist, seed layer, and barrier metal are removed.

[0268] This allows the cured film 3 to conceal the wiring 4, suppress glare from the wiring 4, and make it difficult to see from the outside, thereby improving the design. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0269] The method for producing a display device of the present invention preferably includes a step of repeating the steps (D2), (D3), (D6), and (D5) multiple times to form multiple layers of the cured film having the wiring therein.

[0270] As shown in FIGS. 7e and 7f, the hardened film 3 and the wiring 4 can be formed by repeating the same method again to form a hardened film 3 consisting of two or more layers.

[0271] This allows for the arrangement of multiple light-emitting elements by using multiple layers of cured films having wiring therein, and also makes it possible to suppress wiring defects such as short circuits in the wiring due to a reduced package height and a shorter wiring distance, reduce loss, and improve high-speed response.

[0272] 7g, a barrier metal 9 is formed in the opening pattern 12 of the cured film 3 by sputtering to form a bump 10. The barrier metal 9 may or may not be present.

[0273] 7h, the wiring 4 is electrically connected to a light-emitting element drive substrate 7 having drive elements 8 such as a driver IC via bumps 10, the support substrate 18 is peeled off, and the opposing substrate 5 is attached using an adhesive or the like to obtain a display device 1 having a plurality of light-emitting elements 2. The wiring 4 may include electrodes.

[0274] One or more driving elements 8 may be used for one light-emitting element 2, one unit of light-emitting elements 2 consisting of red, blue, and green, or for multiple light-emitting elements 2 or multiple units of light-emitting elements 2, depending on the function, and for example, one or more driving elements may be disposed near the light-emitting elements during the process of Fig. 7. In this case, the driving element is electrically connected to the light-emitting element 2 via the light-emitting element driving substrate 7, the wiring 4c, the wiring 4 extending into the cured film 3, etc.

[0275] This allows the cured film to conceal the wiring, suppressing glare from the wiring and making it less visible from the outside, enhancing the design. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0276] The method for producing a display device of the present invention preferably includes, before the step (D1), a step (D8) of providing a partition wall having a thickness equal to or greater than that of the light-emitting element.

[0277] An example of step (D8) is shown in Figure 17. Figure 17a shows step (D8) of providing partition walls 15 having a thickness equal to or greater than that of the light-emitting element 2 on a support substrate 18, and the following Figure 17b shows step (D1) of providing a plurality of light-emitting elements 2 between partition walls having a thickness equal to or greater than that of the light-emitting element 2. Figure 17c shows a step of disposing a resin film 19, similar to step (D2) shown in Figure 7b, while leaving the partition walls 15 in place. The subsequent steps are carried out as shown in Figure 7. The partition walls may be made of resin (A), or may be made of known materials such as epoxy resin, (meth)acrylic polymer, polyurethane, polyester, polyolefin, or polysiloxane. Light-shielding or reflective portions may also be provided.

[0278] In the manufacturing method of the display device of the present invention, after the step (D5), it is preferable to further include a step (D9) in which a driving element and a substrate are provided, the driving element is connected to the light-emitting element through wiring, and at least a portion of the wiring extends to the side of the substrate.

[0279] An example of step (D9) is shown in Figure 7. Figure 7h shows step (D9) having a driving element and a substrate, and the driving element is connected to the light-emitting element through wiring. As shown in Figure 7h, the driving element is connected to the light-emitting element 2 through wiring 4 and 4c, and part of the wiring 4c extends to the side surface of the light-emitting element driving substrate 7. If the light-emitting element driving substrate 7 has a through electrode, it may be connected to the driving element 8 through the through electrode.

[0280] This allows the display device itself to be made lower in height and have improved high-speed response, and further allows the display device to be made smaller and have a narrower frame.

[0281] The method for producing a display device of the present invention preferably further comprises the step (D10) of providing a light-shielding layer between the plurality of light-emitting elements.

[0282] An example of step (D10) is shown in Fig. 18. Fig. 18a shows step (D10) of providing a light-shielding layer 25 between a plurality of light-emitting elements 2. The light-shielding layer 25 may be formed before or after the light-emitting elements 2 are formed.

[0283] The light-shielding layer 25 may be composed of a cured film obtained by curing a resin composition containing (A) resin and (E) colorant. Alternatively, it may be composed of a material other than the resin composition containing (A), such as known materials such as epoxy resin, (meth)acrylic polymer, polyurethane, polyester, polyolefin, and polysiloxane. The (E) colorant may be a black pigment, such as black organic pigments such as carbon black, perylene black, and aniline black; graphite; and inorganic pigments such as metal fine particles of titanium, copper, iron, manganese, cobalt, chromium, nickel, zinc, calcium, and silver, metal oxides, composite oxides, metal sulfides, metal nitrides, and metal oxynitrides. Furthermore, a black color may be achieved by combining a red pigment and a blue pigment, or, if necessary, a yellow pigment or other pigment. Dyes may also be used. Two or more colorants may be used.

[0284] The resin composition containing the (A) resin and the (E) colorant may be made photosensitive, and a (B) photosensitizer described below may be used.

[0285] As a method for forming the light-shielding layer, if the light-shielding layer is photosensitive, a photolithography process may be used. If the light-shielding layer is not photosensitive, a photolithography process or an etching process may be used after forming a photoresist on the light-shielding layer, or an etching process using a mask may be used. A patterned colored film can be obtained by subjecting the obtained pattern to a heat treatment (post-baking). The heat treatment may be performed in air, a nitrogen atmosphere, or a vacuum. The heating temperature is preferably 100 to 300°C, and the heating time is preferably 0.25 to 5 hours. The heating temperature may be changed continuously or in steps.

[0286] The method for manufacturing a display device of the present invention is a method for manufacturing a display device having at least wiring, a cured film, and light-emitting elements each having electrodes on two different surfaces, and includes the steps of: (E1) arranging pads on a support substrate; (E2) forming a resin film made of a resin composition containing a resin (A) on the support substrate and the pads; (E3) forming a pattern of a plurality of through-holes in the resin film by exposing and developing the resin film; (E10) curing the resin film to form the cured film having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm; (E5) forming the wiring on at least a portion of the surface of the cured film and in the opening pattern of the cured film; and (E6) arranging the light-emitting elements on the cured film so as to maintain electrical connection with the wiring.

[0287] 8 shows a cross-sectional view of a plane perpendicular to the support substrate or the opposing substrate, illustrating another example of a manufacturing process for the display device 1 of the present invention. Since the process overlaps with that of FIG. 7, specifically, FIG. 8b to FIG. 8e overlaps with FIG. 7b to FIG. 7f, the explanation is omitted.

[0288] 8a, the step (E1) is a step of arranging pads 17 on a support substrate 18. The pads may be made of copper or aluminum.

[0289] Next, in step (E2), as shown in Fig. 8b, a resin composition or a resin sheet containing the (A) resin is applied or laminated onto the support substrate 18 and the pads 17 to form a resin film 19. Note that "on the support substrate" and "on the pads" does not only mean the surface of the support substrate or the surface of the pads, but also means the upper side of the support substrate or the pads, and the resin film may be formed by applying or laminating the resin composition containing the (A) resin or a resin sheet formed from the resin composition containing the (A) resin onto a cured film, wiring, or partition wall.

[0290] Next, in step (E3), as shown in FIG. 8c, a plurality of penetrating opening patterns 12 are formed in the resin film 19 using a photolithography process.

[0291] 8c, step (E10) is a step of forming a cured film 3 having a transmittance of 0.1% or more and 95% or less at a wavelength of 450 nm when the resin film 19 is cured to a thickness of 1 μm. Alternatively, step (E4) may be a step of forming a cured film 3 having a transmittance of 0.1% or more and 79% or less at a wavelength of 450 nm when the resin film 19 is cured to a thickness of 5 μm, or step (E8) may be a step of forming a cured film 3 having a transmittance of 0.1% or more and 25% or less at a wavelength of 450 nm when the resin film 19 is cured to a thickness of 1 μm.

[0292] Next, in FIG. 8c, in order to improve the adhesion between the hardened film 3 and the wiring 4, a barrier metal such as titanium is sputtered on the hardened film 3, and a copper seed (seed layer) is further formed on top of that by sputtering.

[0293] Next, in step (E5), as shown in Fig. 8d, a photoresist layer (not shown) is formed, and then wiring 4 made of copper, a conductive film, or the like is formed on the opening pattern 12 of the cured film 3 and on part of the surface of the cured film 3 by plating, sputtering, processing a photosensitive conductive paste, or the like. Thereafter, unnecessary photoresist, seed layer, and barrier metal are removed.

[0294] The method for manufacturing a display device of the present invention preferably includes a step of repeating the steps (E2), (E3), (E10), and (E5) multiple times to form multiple layers of the cured film having the wiring therein.

[0295] As shown in FIGS. 8b to 8d, the cured film 3 and the wiring 4 can be repeatedly formed in the same manner to form a cured film 3 consisting of two or more layers as shown in FIG. 8e.

[0296] Next, in step (E6), as shown in FIG. 8f, the light-emitting element 2 is disposed on the cured film 3 so as to maintain electrical connection with the wiring 4. The electrode 6 of the light-emitting element 2 may be directly connected to the wiring 4, or may be connected via, for example, a bump or a conductive film. Furthermore, as shown in FIG. 8g, it is preferable to have step (E7) of forming a cured film 21 on the cured film 3 and the light-emitting element 2. The cured film 21 is preferably formed by applying a resin composition containing the (A) resin or laminating a resin sheet composed of the resin composition containing the (A) resin to form a resin film composed of the resin composition, and then curing the resin film 21. The cured film 21 may also be formed from a material other than the resin composition containing the (A) resin, and known materials such as epoxy resin, silicone resin, and fluororesin may also be used.

[0297] The curing conditions vary depending on the type of resin, but examples include 80°C to 230°C and 15 minutes to 5 hours. The purpose of this is to protect and flatten the light-emitting element by forming a cured film on the light-emitting element.

[0298] 8g shows an example in which wiring 4d is formed on the cured film 21 after it has been formed. The electrode 6 and wiring 4d may be connected via a bump or a conductive film, or may be connected directly. Furthermore, the wiring 4d may be connected to wiring 4 extending in the cured film 3 arranged so as to contact at least a portion of the light-emitting element 2 via a through electrode, or may be connected to the light-emitting element driving substrate 7.

[0299] 8h, the opposing substrate 5 is bonded to the cured film 21 using an adhesive or the like. The support substrate 18 is then peeled off, and a barrier metal 9 and bumps 10 are formed, which are electrically connected via the bumps 10 to the light-emitting element drive substrate 7 to which drive elements 8 such as driver ICs are attached.

[0300] The driving elements 8 are electrically connected to the light-emitting elements 2 via wiring 4 extending into the cured film 3, thereby obtaining a display device 1 having a plurality of light-emitting elements 2. The wiring 4 may include electrodes.

[0301] One or more driving elements 8 may be used for one light-emitting element 2, one unit of light-emitting elements 2 consisting of red, blue, and green, or for multiple light-emitting elements 2 or multiple units of light-emitting elements 2, depending on the function, and for example, one or more driving elements may be disposed near the light-emitting elements during the process of Fig. 8. In this case, the driving element is electrically connected to the light-emitting element 2 via the light-emitting element driving substrate 7, the wiring 4c, the wiring 4 extending into the cured film 3, etc.

[0302] This allows the cured film 3 to conceal the wiring 4, suppress glare from the wiring 4, and make it difficult to see from the outside, thereby improving the design. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0303] The method for producing a display device of the present invention preferably includes, after the step (E5), a step (E9) of providing a partition wall having a thickness equal to or greater than the thickness of the light-emitting element.

[0304] An example of step (E9) is shown in Fig. 9. Fig. 9f shows step (E9) of forming multiple layers of the cured film 3 shown in Fig. 8e and then providing partition walls 15. Thereafter, as shown in Fig. 9g, light-emitting elements 2 are provided between the partition walls 15. Next, as shown in Fig. 9h, wiring 4d and electrodes 6 are electrically connected. Also, an opposing substrate 5 is attached to the upper portions of the partition walls 15 and the light-emitting elements 2, and the support substrate 18 is peeled off. A barrier metal 9 and bumps 10 are formed, and the light-emitting elements are electrically connected via the bumps 10 to a light-emitting element drive substrate 7 having drive elements 8 such as driver ICs.

[0305] Preferably, the method for manufacturing a display device of the present invention further includes, after step (E7), step (E11) of providing a driving element and a substrate, the driving element being connected to the light-emitting element through wiring, and at least a portion of the wiring extending to the side of the substrate.

[0306] An example of step (E11) is shown in Figure 8. Figure 8h shows step (E11) in which a driving element and a substrate are provided, and the driving element is connected to the light-emitting element through wiring. As shown in Figure 8h, the driving element is connected to the light-emitting element 2 through wiring 4 and 4c, and part of the wiring 4c extends to the side surface of the light-emitting element driving substrate 7. If the light-emitting element driving substrate 7 has a through electrode, it may be connected to the driving element 8 through the through electrode.

[0307] This allows the display device itself to be made lower in height and have improved high-speed response, and further allows the display device to be made smaller and have a narrower frame.

[0308] The method for manufacturing a display device of the present invention is a method for manufacturing a display device having at least wiring, a cured film, and light-emitting elements each having electrodes on two different surfaces, and includes the steps of: (F1) forming a resin film made of a resin composition containing a resin (A) on a substrate or the like; (F2) forming a pattern of openings that penetrate the resin film by exposing and developing the resin film; (F3) curing the resin film to form the cured film having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm; (F4) forming the wiring on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film; and (F5) arranging the light-emitting elements on the cured film so as to maintain electrical connection with the wiring.

[0309] 19A and 19B are cross-sectional views taken along a plane perpendicular to the light-emitting element drive substrate, illustrating an example of a manufacturing process for a display device 1 according to the second aspect of the present invention. Step (F1), as shown in Fig. 19A, is a process for forming a resin film made of a resin composition containing the (A) resin on a substrate or the like. The resin film may be formed by applying or laminating a resin composition containing the (A) resin or a resin sheet formed from a resin composition containing the (A) resin.

[0310] The substrate can be a light emitting element driving substrate 7. Figure 19a shows an example of a TFT array substrate in which TFTs 22, insulating films 23, and wiring 4 are arranged on a glass substrate.

[0311] The insulating film 23 is not particularly limited, but examples thereof include a silicon oxide film, a silicon nitride film, and an insulating film made of an organic material.

[0312] Next, in step (F2), as shown in FIG. 19a, a plurality of penetrating opening patterns are formed in the resin film using a photolithography process.

[0313] Next, in step (F3), as shown in FIG. 19a, the resin film is cured to form a cured film 3 having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm.

[0314] Next, in step (F4), as shown in Fig. 19b, wiring is formed on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film. After forming a photoresist layer (not shown), wiring 4e is formed on the surface of a portion of the cured film 3 by, for example, sputtering or processing a photosensitive conductive paste. Thereafter, unnecessary photoresist is removed.

[0315] Examples of wiring 4e include gold, silver, copper, aluminum, nickel, titanium, molybdenum, alloys containing these, compounds containing as a main component an oxide of at least one element selected from the group consisting of indium, gallium, zinc, tin, titanium, and niobium, and photosensitive conductive pastes containing organic matter and conductive particles, but other known materials may also be used.

[0316] The method for producing a display device of the present invention preferably includes a step of repeating the steps (F1), (F2), (F3), and (F4) multiple times to form multiple layers of the cured film having the wiring therein.

[0317] By repeating the same process again, the hardened film 3 can be formed into two or more layers as shown in Fig. 19c. Then, the wiring 4c is formed.

[0318] Next, in step (F5), as shown in Fig. 19d, the light-emitting element 2 is disposed on the cured film 3 so as to maintain electrical connection with the wiring 4e. The electrode 6 and the wiring 4e may be connected via a bump or a conductive film, or may be connected directly.

[0319] Furthermore, the partition wall 15 may be formed before or after arranging the light-emitting elements 2. Then, the cured film 21 is formed, and then the wiring 4d is formed. The wiring 4d may be connected to the wiring 4, 4e extending in the cured film 3 arranged so as to contact at least a part of the light-emitting elements 2 via a through electrode or the like, or may be connected to the light-emitting element driving substrate 7.

[0320] 19e, an opposing substrate 5 is attached using an adhesive or the like. Furthermore, a driving element 8 such as a driver IC is electrically connected to the light-emitting element 2 via the wiring 4c and the wirings 4 and 4e extending into the cured film 3, thereby obtaining a display device 1 having a plurality of light-emitting elements 2. Note that the wirings 4d and 4e also include electrodes.

[0321] One or more driving elements 8 may be used for one light-emitting element 2, one unit of light-emitting elements 2 consisting of red, blue, and green, or for multiple light-emitting elements 2 or multiple units of light-emitting elements 2, depending on the function, and for example, one or more driving elements may be disposed near the light-emitting elements during the process of Fig. 19. In this case, the driving element is electrically connected to the light-emitting element 2 via the light-emitting element driving substrate 7, the wiring 4c, the wiring 4 extending into the cured film 3, etc.

[0322] This allows the cured film to ensure electrical insulation of the wiring, and extending the wiring through the cured film electrically connects the electrodes of the light-emitting element and the driving element, thereby controlling light-emitting operation. The cured film also conceals the wiring, suppressing glare and making it less visible from the outside, improving design. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0323] The method for manufacturing a display device of the present invention is a method for manufacturing a display device having at least wiring, a cured film, and light-emitting elements each having an electrode on two different surfaces, and may include the steps of: (G1) forming a resin film made of a resin composition containing a resin (A) on a substrate or the like; (G2) exposing and developing the resin film to form a pattern of openings that penetrate the resin film; (G3) curing the resin film to form the cured film having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm; (G4) forming the wiring on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film; and (G5) arranging the light-emitting elements so as to maintain electrical connection with the wiring.

[0324] FIG. 29 is a cross-sectional view taken along a plane perpendicular to the light-emitting element driving substrate, showing an example of a manufacturing process for the display device 1 according to the second embodiment of the present invention.

[0325] 29a, the step (G1) is a step of forming a resin film made of a resin composition containing the (A) resin on a substrate, etc. The resin film may be formed by applying or laminating a resin composition containing the (A) resin or a resin sheet formed from the resin composition containing the (A) resin.

[0326] The substrate can be a light emitting element driving substrate 7. Figure 29a shows an example of a TFT array substrate in which TFTs 22, insulating films 23, and wiring 4 are arranged on a glass substrate.

[0327] The insulating film 23 is not particularly limited, but examples thereof include a silicon oxide film, a silicon nitride film, and an insulating film made of an organic material.

[0328] Next, in the step (G2), as shown in FIG. 29a, a plurality of penetrating opening patterns are formed in the resin film using a photolithography process.

[0329] Next, in step (G3), as shown in FIG. 29a, the resin film is cured to form a cured film 3 having a transmittance of 0.1% or more and 95% or less for light with a wavelength of 450 nm at a thickness of 1 μm.

[0330] Next, in step (G4), as shown in Fig. 29b, wiring is formed on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film. After forming a photoresist layer (not shown), wiring 4e is formed on the surface of a portion of the cured film 3 by, for example, sputtering or processing a photosensitive conductive paste. Thereafter, unnecessary photoresist is removed.

[0331] Examples of wiring 4e include gold, silver, copper, aluminum, nickel, titanium, molybdenum, alloys containing these, compounds containing as a main component an oxide of at least one element selected from the group consisting of indium, gallium, zinc, tin, titanium, and niobium, and photosensitive conductive pastes containing organic matter and conductive particles, but other known materials may also be used.

[0332] Thereafter, wiring 4c is formed as shown in FIG. 29c.

[0333] Next, in step (G5), as shown in Fig. 29d, the light-emitting element 2 is disposed so as to be electrically connected to the wiring 4e. The electrode 6 and the wiring 4e may be connected via a bump or a conductive film, or may be connected directly.

[0334] The cured film 3 or the partition wall 15 may be formed before or after arranging the light-emitting elements 2. Then, the cured film 21 is formed, and then the wiring 4d is formed. The wiring 4d may be connected to the wiring 4, 4e extending in the cured film 3 arranged so as to contact at least a part of the light-emitting elements 2 via a through electrode or the like, or may be connected to the light-emitting element driving substrate 7.

[0335] 29e, an opposing substrate 5 is attached using an adhesive or the like. Furthermore, a driving element 8 such as a driver IC is electrically connected to the light-emitting element 2 via the wiring 4c and the wirings 4 and 4e extending into the cured film 3, thereby obtaining a display device 1 having a plurality of light-emitting elements 2. The wirings 4d and 4e also include electrodes.

[0336] One or more driving elements 8 may be used for one light-emitting element 2, one unit of light-emitting elements 2 consisting of red, blue, and green, or for multiple light-emitting elements 2 or multiple units of light-emitting elements 2, depending on the function, and for example, one or more driving elements may be disposed near the light-emitting elements during the process of Fig. 29. In this case, the driving element is electrically connected to the light-emitting element 2 via the light-emitting element driving substrate 7, the wiring 4c, the wiring 4 extending into the cured film 3, etc.

[0337] This allows the cured film to ensure electrical insulation of the wiring, and extending the wiring through the cured film electrically connects the electrodes of the light-emitting element and the driving element, thereby controlling light-emitting operation. The cured film also conceals the wiring, suppressing glare and making it less visible from the outside, improving design. Furthermore, visibility can be improved by reducing external light reflection and improving contrast.

[0338] The display device of the present invention is suitably used for display devices such as various LED displays and various vehicle-mounted lamps.

[0339] The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The display devices in the examples and the cured films made of the resin compositions used in the display devices were evaluated by the following methods.

[0340] <Method for Evaluating the Light Transmittance of Cured Film> A varnish made of a resin composition was spin-coated onto a 5 cm square glass substrate so that the film thickness after heat treatment at 230°C for 1 hour would be 1.0 μm or less, and the substrate was pre-baked at 120°C for 3 minutes. Thereafter, using a high-temperature clean oven CLH-21CD-S manufactured by Koyo Thermo Systems Co., Ltd., the temperature was raised from 50°C to 110°C at a rate of 3.5°C / min under a nitrogen stream with an oxygen concentration of 100 ppm or less, and then heat-treated at 110°C for 30 minutes. Thereafter, the temperature was raised at a rate of 3.5°C / min to the heating temperature of 230°C, and then heat-treated for 1 hour at the heating temperature after the temperature increase, and the coated film was dried and heat-treated to obtain a cured film. The film thickness of the coating film after pre-baking and after development was measured using an optical interference type film thickness measuring device Lambda Ace STM-602 manufactured by Dainippon Screen Mfg. Co., Ltd., with a refractive index of 1.629, and the film thickness of the cured film was measured with a refractive index of 1.629.

[0341] The transmittance of the cured film thus obtained was measured at a wavelength of 450 nm using a double beam spectrophotometer U-2910 (manufactured by Hitachi High-Tech Science Corp.) If the film thickness of the heat-resistant resin film after the heat treatment was not 1.0 μm or 5.0 μm, the measured film thickness of the transmission spectrum was converted into a value of 1.0 μm or 5.0 μm according to Lambert's law.

[0342] <Method for evaluating the concealment ability of the cured film to conceal wiring> The concealment ability of the cured film to conceal wiring was evaluated using the display devices described in the following Examples and Comparative Examples. A microscope was used for the measurement. The glare of the wiring was suppressed using the microscope and visually evaluated to see whether it was concealed. Display devices in which the glare of at least a portion of the wiring was suppressed by the cured film and made difficult to see were considered to be concealed and rated as good, with a rating of 2. Display devices in which the wiring could be clearly seen visually through the cured film were considered to be poor, with a rating of 1.

[0343] <Evaluation of opening pattern shape of cured film made of resin composition> A varnish made of the resin composition was prepared and applied to an 8-inch silicon wafer by spin coating using a coating and developing apparatus ACT-8 (manufactured by Tokyo Electron Limited) so that the film thickness after heating would be 5 μm, followed by pre-baking to prepare a pre-baked film. Pre-baking was carried out at 120°C for 3 minutes. Thereafter, an i-line stepper (manufactured by Nikon Corporation, NSR-2205i14) was used to apply 50 to 1000 mJ / cm ２ The exposure was performed with an exposure dose of 1000 u. The size of the circular pattern used for exposure was 5 to 30 μm. After exposure, the film was developed using a 2.38% by mass aqueous solution of tetramethylammonium (TMAH) (manufactured by Tama Chemicals) under conditions such that the change in film thickness in the unexposed areas before and after development was 1.0 to 1.5 μm, followed by rinsing with pure water and shaking off to dry, to obtain a patterned film. Alternatively, the film was developed using cyclopentanone and shaking off to dry, to obtain a patterned film. In the case of a non-photosensitive material, a photoresist was formed before exposure, followed by exposure and development, and then the photoresist was removed after development. The film thickness after pre-baking and development was measured using a Lambda Ace STM-602 optical interference film thickness measuring device manufactured by Dainippon Screen Mfg. Co., Ltd., with a refractive index of 1.629.

[0344] After development, the pattern-forming film was heated in an inert oven CLH-21CD-S (manufactured by Koyo Thermo Systems Co., Ltd.) under a nitrogen stream with an oxygen concentration of 20 ppm or less by raising the temperature from 50°C to 100°C at a rate of 3.5°C / min, and then heat-treated at 100°C for 30 minutes. Thereafter, the temperature was raised to 230°C at a rate of 3.5°C / min, and then heat-treated for 1 hour to harden the pattern-forming film, thereby obtaining a hardened film.

[0345] When the temperature reached 50°C or less, the wafer was removed, and then the wafer was cleaved to observe and measure the cross-sectional shape of the 5 to 30 µm circular pattern using a scanning electron microscope S-4800 (manufactured by Hitachi High-Technologies Corporation). The angle of the slanted side was determined by connecting the opening pattern at a position halfway along the thickness direction of the cured film with the opening pattern at the bottom.

[0346] As a result, the angle of the inclined side was evaluated as level A when it was 55° or more and 80° or less, level B when it was 40° or more and less than 55° or more than 80° and 85° or less, and level C when it was less than 40° or more than 85°.

[0347] Synthesis Example 1: Synthesis of Hydroxyl Group-Containing Diamine Compound 18.3 g (0.05 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (manufactured by Central Glass Co., Ltd., hereinafter referred to as BAHF) was dissolved in 100 mL of acetone and 17.4 g (0.3 mol) of propylene oxide (manufactured by Tokyo Chemical Industry Co., Ltd.), and the solution was cooled to −15°C. To this solution, a solution prepared by dissolving 20.4 g (0.11 mol) of 3-nitrobenzoyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) in 100 mL of acetone was added dropwise. After completion of the dropwise addition, the mixture was stirred at −15°C for 4 hours and then returned to room temperature. The precipitated white solid was filtered and dried in vacuo at 50°C.

[0348] 30 g of the obtained white solid was placed in a 300 mL stainless steel autoclave and dispersed in 250 mL of methyl cellosolve, and 2 g of 5% palladium-carbon (manufactured by Wako Pure Chemical Industries, Ltd.) was added. Hydrogen was introduced into the autoclave using a balloon, and a reduction reaction was carried out at room temperature. After approximately 2 hours, the reaction was terminated when it was confirmed that the balloon no longer deflated. After the reaction was completed, the palladium compound catalyst was removed by filtration, and the mixture was concentrated using a rotary evaporator to obtain a hydroxyl group-containing diamine compound represented by the following formula:

[0349]

[0350] Synthesis Example 2: Synthesis of Polybenzoxazole Precursor (A-1) Under a dry nitrogen stream, 1.5 g (0.0075 mol) of 4,4'-diaminodiphenyl ether (hereinafter referred to as 4,4'-DAE), 12.8 g (0.035 mol) of BAHF, and 5.0 g (0.0050 mol) of RT-1000 (manufactured by HUNTSMAN Corp.) were dissolved in 100 g of NMP. To this solution, dodecanoic acid diimidazole (7.4 g, 0.023 mol) and 1,1'-(4,4'-oxybenzoyl)diimidazole (hereinafter referred to as PBOM) (8.1 g, 0.023 mol) were added along with 25 g of NMP, and the mixture was allowed to react at 85°C for 3 hours. Next, 0.6 g (0.0025 mol) of 1,3-bis(3-aminopropyl)tetramethyldisiloxane (hereinafter referred to as SiDA), 0.8 g (0.0025 mol) of 4,4'-oxydiphthalic anhydride (hereinafter referred to as ODPA), and 0.8 g (0.0050 mol) of 5-norbornene-2,3-dicarboxylic anhydride (hereinafter sometimes referred to as NA) were added together with 25 g of NMP, and the mixture was reacted at 85°C for 1 hour. After completion of the reaction, the mixture was cooled to room temperature, and 13.2 g (0.25 mol) of acetic acid was added together with 25 g of NMP, and the mixture was stirred at room temperature for 1 hour. After completion of stirring, the solution was poured into 1.5 L of water to obtain a white precipitate. This precipitate was collected by filtration, washed three times with water, and then dried in a forced-air dryer at 50°C for 3 days to obtain a powder of polybenzoxazole precursor (A-1).

[0351] Synthesis Example 3: Synthesis of Polybenzoxazole Precursor (A-2) Under a dry nitrogen stream, 27.5 g (0.075 mol) of BAHF was dissolved in 257 g of NMP. To this solution, 17.2 g (0.048 mol) of PBOM was added along with 20 g of NMP, and the mixture was allowed to react at 85°C for 3 hours. Subsequently, 20.0 g (0.02 mol) of RT-1000 (manufactured by HUNTSMAN Corporation), 1.2 g (0.005 mol) of SiDA, and 14.3 g (0.04 mol) of PBOM were added along with 50 g of NMP, and the mixture was allowed to react at 85°C for 1 hour. Furthermore, 3.9 g (0.024 mol) of 5-norbornene-2,3-dicarboxylic anhydride was added as an end-capping agent along with 10 g of NMP, and the mixture was allowed to react at 85°C for 30 minutes. After the reaction was completed, the mixture was cooled to room temperature, and 52.8 g (0.50 mol) of acetic acid was added together with 87 g of NMP, followed by stirring at room temperature for 1 hour. After stirring was completed, the solution was poured into 3 L of water to obtain a white precipitate. This precipitate was collected by filtration, washed three times with water, and then dried in a forced air dryer at 50°C for 3 days to obtain a powder of polybenzoxazole precursor (A-2).

[0352] Synthesis Example 4: Synthesis of Polyimide Precursor (A-3) Under a dry nitrogen stream, 51.9 g (0.086 mol) of the hydroxyl group-containing diamine obtained in Synthesis Example 1 and 1.0 g (0.004 mol) of SiDA were dissolved in 200 g of NMP. 31.0 g (0.10 mol) of ODPA was added thereto, and the mixture was stirred at 40°C for 2 hours. 1.1 g (0.01 mol) of 3-aminophenol (manufactured by Tokyo Chemical Industry Co., Ltd.) as an end-capping agent was then added together with 10 g of NMP, and the mixture was allowed to react at 40°C for 1 hour. Subsequently, a solution prepared by diluting 7.1 g (0.06 mol) of dimethylformamide dimethyl acetal (manufactured by Mitsubishi Rayon Co., Ltd., hereinafter referred to as DFA) with 5 g of NMP was added dropwise. After the dropwise addition, stirring was continued for 2 hours at 40°C. After stirring was completed, the solution was poured into 2 L of water, and the polymer solid precipitate was collected by filtration. The mixture was further washed three times with 2 L of water, and the collected polymer solid was dried in a vacuum dryer at 50° C. for 72 hours to obtain a polyimide precursor (A-3).

[0353] Synthesis Example 5: Synthesis of Polyimide Precursor (A-4) Under a dry nitrogen stream, 41.1 g (0.068 mol) of the hydroxyl group-containing diamine obtained in Synthesis Example 1, 18.0 g (0.018 mol) of a diamine containing propylene oxide and a tetramethylene ether glycol structure (RT-1000, manufactured by HUNTSMAN Corporation), and 1.0 g (0.004 mol) of SiDA were dissolved in 200 g of NMP. 31.0 g (0.10 mol) of ODPA was added thereto, and the mixture was stirred at 40°C for 2 hours. 1.1 g (0.01 mol) of 3-aminophenol as an end-capping agent was then added together with 10 g of NMP, and the mixture was allowed to react at 40°C for 1 hour. Thereafter, a solution prepared by diluting 6.0 g (0.05 mol) of DFA with 5 g of NMP was added dropwise. After the dropwise addition, stirring was continued at 40°C for 2 hours. After stirring, the solution was poured into 2 L of water, and the precipitated polymer solid was collected by filtration. The mixture was further washed three times with 2 L of water, and the collected polymer solid was dried in a vacuum dryer at 50°C for 72 hours to obtain a polyimide precursor (A-4).

[0354] Synthesis Example 6: Synthesis of Polyimide (A-5) Under a dry nitrogen stream, 29.3 g (0.08 mol) of BAHF, 1.2 g (0.005 mol) of SiDA, and 3.3 g (0.03 mol) of 3-aminophenol as an end-capping agent were dissolved in 80 g of NMP. 31.2 g (0.1 mol) of ODPA was added to the solution together with 20 g of NMP, and the mixture was reacted at 60°C for 1 hour, followed by stirring at 180°C for 4 hours. After stirring, the solution was poured into 3 L of water to obtain a white precipitate. The precipitate was collected by filtration, washed three times with water, and then dried in a vacuum dryer at 80°C for 20 hours to obtain a powder of polyimide (A-5).

[0355] Synthesis Example 7: Synthesis of Cardo Resin (A-6) Under a dry nitrogen stream, 198.53 g of a 50% PGMEA solution of an equiequivalent reaction product of bisphenolfluorene epoxy resin and acrylic acid (manufactured by Nippon Steel Chemical Co., Ltd., product name "ASF-400" solution), 39.54 g (0.12 mol) of benzophenonetetracarboxylic dianhydride, 8.13 g (0.08 mol) of succinic anhydride, 48.12 g of PGMEA, and 0.45 g of triphenylphosphine were charged into a four-neck flask equipped with a reflux condenser. The mixture was stirred for 1 hour while heating to 120 to 125°C, and further heated and stirred for 6 hours at 75 to 80°C. Thereafter, 8.6 g of glycidyl methacrylate was added, and the mixture was further stirred at 80°C for 8 hours to obtain a resin (A-6) having a skeletal structure in which two cyclic structures are bonded to a quaternary carbon atom constituting the cyclic structure.

[0356] Synthesis Example 8: Synthesis of Phenolic Resin (A-7) Under a dry nitrogen stream, 108.1 g (1.0 mol) of m-cresol, 34.0 g (0.32 mol) of benzaldehyde, 90.4 g (0.74 mol) of salicylaldehyde, 200 g of ethanol, and 8.6 g (0.05 mol) of paratoluenesulfonic acid were charged into a reaction vessel and reacted for 18 hours under reflux at 65°C. After neutralizing the reaction system with caustic soda, methyl isobutyl ketone and water were added, and the mixture was subjected to separation and washing five times. Methyl isobutyl ketone was distilled off under reduced pressure at 100°C using an evaporator, to obtain phenolic resin (A-7).

[0357] Synthesis Example 9: Synthesis of Photosensitizer (Quinone Diazide Compound) (B-1) Under a dry nitrogen stream, 21.2 g (0.05 mol) of 4,4'-[1-[4-[1-(4-hydroxyphenyl-1)-1-methylethyl]phenyl]ethylidene]bisphenol (manufactured by Honshu Chemical Industry Co., Ltd., hereinafter referred to as TrisP-PA) and 26.8 g (0.10 mol) of 5-naphthoquinone diazide sulfonic acid chloride (manufactured by Toyo Gosei Co., Ltd., NAC-5) were dissolved in 450 g of γ-butyrolactone (hereinafter also referred to as GBL) at room temperature. 12.7 g of triethylamine mixed with 50 g of γ-butyrolactone was added dropwise to the solution so that the temperature in the system did not exceed 35°C. After the dropwise addition, the mixture was stirred at 40°C for 2 hours. The triethylamine salt was filtered, and the filtrate was poured into water. The precipitate was then collected by filtration and washed with 1 L of 1% aqueous hydrochloric acid, and then washed twice with 2 L of water. The precipitate was dried in a vacuum dryer to obtain a quinone diazide compound (B-1) represented by the following formula:

[0358]

[0359] Synthesis Example 10: Synthesis of Photosensitizer (Quinone Diazide Compound) (B-2) Under a dry nitrogen stream, 21.2 g (0.05 mol) of TrisP-PA and 26.8 g (0.10 mol) of 4-naphthoquinone diazide sulfonic acid chloride (NAC-5, manufactured by Toyo Gosei Co., Ltd.) were dissolved in 450 g of γ-butyrolactone at room temperature. 12.7 g of triethylamine mixed with 50 g of γ-butyrolactone was added dropwise thereto so that the temperature in the system did not exceed 35°C. After the dropwise addition, the mixture was stirred at 40°C for 2 hours. The triethylamine salt was filtered, and the filtrate was poured into water. The precipitate was then collected by filtration and washed with 1 L of 1% aqueous hydrochloric acid. This was then washed twice with 2 L of water. The precipitate was dried in a vacuum dryer to obtain quinone diazide compound (B-2) represented by the following formula:

[0360]

[0361] Synthesis Example 11: Synthesis of Polyimide Precursor (A-8) Under a dry nitrogen stream, 3.2 g (0.03 mol) of 1,4-paraphenylenediamine and 12.0 g (0.06 mol) of 4,4'-DAE were dissolved in 200 g of NMP. 31.0 g (0.10 mol) of ODPA was added thereto, and the mixture was stirred at 40°C for 2 hours. 1.1 g (0.01 mol) of 3-aminophenol (manufactured by Tokyo Chemical Industry Co., Ltd.) as an end-capping agent was then added together with 10 g of NMP, and the mixture was allowed to react at 40°C for 1 hour. Subsequently, a solution prepared by diluting 7.1 g (0.06 mol) of DFA with 5 g of NMP was added dropwise. After the dropwise addition, stirring was continued at 40°C for 2 hours. After stirring was completed, the solution was poured into 2 L of water, and the polymer solid precipitate was collected by filtration. The mixture was further washed three times with 2 L of water, and the collected polymer solid was dried in a vacuum dryer at 50° C. for 72 hours to obtain a polyimide precursor (A-8).

[0362] Synthesis Example 12: Synthesis of Polyimide Precursor (A-9) 155.1 g (0.50 mol) of ODPA was placed in a 2-L separable flask, and 134.0 g (1.00 mol) of 2-hydroxyethyl methacrylate (HEMA) and 400 g of γ-butyrolactone were added. 79.1 g of pyridine was added with stirring at room temperature to obtain a reaction mixture. After the heat generated by the reaction had ceased, the mixture was allowed to cool to room temperature and then allowed to stand for a further 16 hours.

[0363] Next, under ice cooling, a solution of 206.3 g (1.00 mol) of dicyclohexylcarbodiimide (DCC) dissolved in 180 g of γ-butyrolactone was added to the reaction mixture over 40 minutes with stirring. Subsequently, a suspension of 16.2 g (0.15 mol) of 1,4-paraphenylenediamine and 60.1 g (0.30 mol) of 4,4'-DAE suspended in 350 g of γ-butyrolactone was added over 60 minutes with stirring. After further stirring at room temperature for 2 hours, 30 ml of ethyl alcohol was added and the mixture was stirred for 1 hour. Then, 400 g of γ-butyrolactone was added. The precipitate formed in the reaction mixture was removed by filtration to obtain a reaction solution.

[0364] The reaction solution was poured into 3 L of water to obtain a white precipitate, which was collected by filtration, washed twice with water, washed once with isopropanol, and then dried in a vacuum dryer at 50°C for 72 hours to obtain a polyimide precursor (A-9).

[0365] Synthesis Example 13: Synthesis of Acrylic Resin (A-10) In a reaction vessel under a nitrogen atmosphere, 150 g of dimethylaminomethanol (hereinafter referred to as "DMEA"; manufactured by Tokyo Chemical Industry Co., Ltd.) was charged and heated to 80°C using an oil bath. To this, a mixture consisting of 20 g of ethyl acrylate (hereinafter referred to as "EA"), 40 g of 2-ethylhexyl methacrylate (hereinafter referred to as "2-EHMA"), 20 g of styrene (hereinafter referred to as "St"), 15 g of acrylic acid (hereinafter referred to as "AA"), 0.8 g of 2,2'-azobisisobutyronitrile, and 10 g of DMEA was added dropwise over 1 hour. After completion of the dropwise addition, the polymerization reaction was further carried out at 80°C under a nitrogen atmosphere for 6 hours. Thereafter, 1 g of hydroquinone monomethyl ether was added to terminate the polymerization reaction. Subsequently, a mixture consisting of 5 g of glycidyl methacrylate (hereinafter referred to as "GMA"), 1 g of triethylbenzylammonium chloride, and 10 g of DMEA was added dropwise over 0.5 hours. After completion of the dropwise addition, the addition reaction was further carried out at 80°C under a nitrogen atmosphere for 2 hours. The resulting reaction solution was purified with methanol to remove unreacted impurities, and then vacuum dried for 24 hours to obtain acrylic resin (A-10) having a copolymerization ratio (by mass): EA / 2-EHMA / St / GMA / AA = 20 / 40 / 20 / 5 / 15. The acid value of the resulting acrylic resin (A-10) was 103 mgKOH / g.

[0366] Synthesis Example 14: Synthesis of acrylic resin (A-11) A methyl methacrylate / methacrylic acid / styrene copolymer (mass ratio 30 / 40 / 30) was synthesized by the method described in Example 1 of Japanese Patent No. 3120476. 40 parts by mass of glycidyl methacrylate was added to 100 parts by mass of the obtained copolymer, and the mixture was reprecipitated in purified water, filtered, and dried to obtain acrylic resin (A-11) having a weight average molecular weight of 15,000 and an acid value of 110 mgKOH / g.

[0367] Preparation Example 1 Preparation of Photosensitive Conductive Paste 1 Into a 100 mL clean bottle were placed 10.0 g of acrylic resin (A-10) as a resin, 0.50 g of "IRGACURE (registered trademark)" OXE-01 (manufactured by Ciba Japan Co., Ltd.) as a photopolymerization initiator, 5.0 g of DMEA as a solvent, and 2.0 g of "Light Acrylate (registered trademark)" BP-4EA (manufactured by Kyoeisha Chemical Co., Ltd.) as a compound having an unsaturated double bond, and mixed using a rotation-revolution vacuum mixer "Awatori Rentaro ARE-310" (manufactured by Thinky Corporation) to obtain 17.5 g of a resin solution (solid content 71.4% by mass).

[0368] 17.50 g of the resulting resin solution was mixed with 44.02 g of silver particles having an average particle size of 1.0 μm and 0.28 g of carbon black having an average particle size of 0.05 μm, and the mixture was kneaded using a three-roller mill "EXAKT M-50" (manufactured by EXAKT) to obtain 61.8 g of photosensitive conductive paste 1. The average particle sizes of the silver particles and carbon black were determined by observing each particle using an electron microscope (SEM) at a magnification of 10,000 times and a field of view width of 12 μm, measuring the maximum width of each of 40 randomly selected primary particles of silver particles and carbon black, and calculating the number average value thereof.

[0369] Preparation Example 2: Production of Colorant Dispersion (DC-1) Zirconia compound particles Zr-1 (manufactured by Nisshin Engineering Inc.) produced by a thermal plasma method were used as the colorant. 200 g of Zr-1, 114 g of a 35 mass % solution of acrylic polymer (P-1) in propylene glycol monomethyl ether acetate (PGMEA), 625 g of "DISPERBYK (registered trademark)" LPN-2111 having a tertiary amino group and a quaternary ammonium salt as a polymer dispersant, and 661 g of PGMEA were charged into a tank and stirred for 20 minutes with a homomixer to obtain a preliminary dispersion. The obtained preliminary dispersion was supplied to an Ultra Apex Mill disperser manufactured by Kotobuki Industries Co., Ltd., equipped with a centrifugal separator filled with 75% by volume of 0.05 mmφ zirconia beads, and dispersion was carried out for 3 hours at a rotation speed of 8 m / s, thereby obtaining a colorant dispersion (DC-1) having a solid content concentration of 25% by mass and a colorant / resin (mass ratio) of 80 / 20.

[0370] Preparation Example 3: Preparation of Photosensitive Colored Resin Composition 1 To 283.1 g of colorant dispersion (DC-1), 184.4 g of a 35 mass % solution of acrylic resin (A-11) in PGMEA, 50.1 g of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.) as a polyfunctional monomer, 7.5 g of "Irgacure (registered trademark)" 907 (manufactured by BASF) as a photopolymerization initiator, and "KAYACURE (registered trademark)" DETX-S (manufactured by Nippon Kayaku Co., Ltd.) were added. 3.8 g of KBM5103 (manufactured by Shin-Etsu Chemical Co., Ltd.) as an adhesion improver, 12.0 g of KBM5103 (manufactured by Shin-Etsu Chemical Co., Ltd.) as an adhesion improver, and a solution obtained by dissolving 3 g of a 10 mass % solution of silicone surfactant "BYK (registered trademark)" 333 (manufactured by BYK-Chemie Co., Ltd.) in 456.1 g of PGMEA as a surfactant was added, and a photosensitive colored resin composition 1 having a total solid content concentration of 20 mass % and a colorant / resin (mass ratio) = 30 / 70 was obtained.

[0371] Preparation Example 4: Production of Colorant Dispersion Liquid (DC-2) Carbon black (CB-Bk1) whose surface was modified with sulfonic acid groups by the method described in JP-A No. 2008-517330 had a surface elemental composition of (C: 88%, O: 7%, Na: 3%, S: 2%), and in terms of the state of the S element, of the S2p peak components, components attributed to C-S and S-S accounted for 90%, and components attributed to SO and SOx accounted for 10%, and the BET value was 54 m / g.

[0372] This carbon black CB-Bk1 (200 g), acrylic resin (A-11) propylene glycol monomethyl ether acetate 40% by weight solution (94 g), polymer dispersant BYK Japan LPN21116, 40% by weight solution (31 g) and propylene glycol monomethyl ether acetate (675 g) were charged into a tank, and stirred with a homomixer (manufactured by Tokushu Kika) for 1 hour to obtain a preliminary dispersion. Then, 0.05 mmφ zirconia beads (Nikkato YTZ balls) were supplied to an Ultra Apex Mill (manufactured by Kotobuki Industries) equipped with a centrifugal separator filled 70%, and the preliminary dispersion was dispersed for 2 hours at a rotation speed of 8 m / s to obtain a colored dispersion DC-2 of 25% by weight, pigment / resin (mass ratio) = 80 / 20.

[0373] <Preparation Example 5 Preparation of photosensitive colored resin composition 2> To 534.8 g of colorant dispersion (DC-2), 122.1 g of a 40 mass% solution of acrylic resin (A-11) in PGMEA, 47.3 g of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.) as a polyfunctional monomer, 11.8 g of "ADEKA CRUISE" NCI-831 (manufactured by ADEKA Corporation) as a photopolymerization initiator, 12.0 g of KBM5103 (manufactured by Shin-Etsu Chemical Co., Ltd.) as an adhesion improver, and 4 g of a 10 mass% solution of silicone surfactant "BYK (registered trademark)" 333 (manufactured by BYK-Chemie Co., Ltd.) as a surfactant were dissolved in 194.0 g of PGMEA to obtain a photosensitive colored resin composition 2, with a total solids concentration of 25 mass%, colorant / resin (mass ratio) = 45 / 55.

[0374] Preparation Example 6 Preparation of Pigment Dispersion 1 (C-4-1) 57.7 g of "Solsperse (registered trademark)" 20000 (a polyether-based polymer resin dispersant having a tertiary amino group at the molecular end), 750.0 g of PGMEA solvent was mixed and stirred for 10 minutes, and then 192.3 g of titanium nitride (average primary particle size 25 nm; in the table, "TiN") was added and stirred for 30 minutes, after which wet media dispersion treatment and filtration (PP filter pore size 0.8 μm) were performed using a horizontal bead mill to prepare pigment dispersion 1 (C-4-1). The average dispersed particle size of the titanium nitride contained in pigment dispersion 1 was 85 nm.

[0375] Preparation Example 7: Preparation of Pigment Dispersion 2 (C-4-2) Using C.I. Pigment Blue 60 (average primary particle diameter 60 nm), which is an organic blue pigment, C.I. Pigment Red 190 (average primary particle diameter 55 nm), which is an organic red pigment, and C.I. Pigment Yellow 192 (average primary particle diameter 40 nm), each pigment dispersion was prepared in the same manner as in Preparation Example 1. The average dispersed particle diameter of C.I. Pigment Blue 60 contained in the pigment dispersion was 162 nm, the average dispersed particle diameter of C.I. Pigment Red 190 was 110 nm, and the average dispersed particle diameter of C.I. Pigment Yellow 192 was 90 nm. 400.0 g of the organic blue pigment dispersion, 300.0 g of the organic red pigment dispersion, and 300.0 g of the organic yellow pigment dispersion were mixed and stirred for 10 minutes to prepare a pseudo-black dispersion, pigment dispersion 2 (C-4-2).

[0376] Preparation Example 8 Preparation of Pigment Dispersion 3 30.00 g of Solsperse (registered trademark) 20000 was mixed with 850.0 g of PGMEA and stirred for 10 minutes, and then 120.0 g of a benzodifuranone-based pigment (average primary particle diameter 50 nm; BASF Irgaphor (registered trademark) Black S0100), which is an organic black pigment, was added and stirred for 30 minutes. Pigment Dispersion 3 (C-4-3) was then prepared using a horizontal bead mill in the same manner as in Preparation Example 3. The average dispersed particle diameter of the benzodifuranone-based pigment contained in Pigment Dispersion 3 was 120 nm.

[0377] The components (B-3), (C-1), (C-2), (C-3), (F-1), (F-2), other components, and solvents used in the examples and comparative examples are shown below. Component (B-3): Photopolymerization initiator NCI-831 (manufactured by ADEKA Corporation) Component (C-1): Plast Yellow 8070 (maximum absorption wavelength: 460 nm) (manufactured by Arimoto Chemical Industry Co., Ltd.) Component (C-2): Oil Scarlet 5206 (maximum absorption wavelength: 530 nm) (manufactured by Arimoto Chemical Industry Co., Ltd.) Component (C-3): Plast Blue 8540 (maximum absorption wavelength: 660 nm) (manufactured by Arimoto Chemical Industry Co., Ltd.) Other components: Radical polymerizable compound: Component (F-1): Dipentaerythritol hexaacrylate (DPHA, manufactured by Kyoeisha Chemical Co., Ltd.) Thermal crosslinking agent: Component (G-1): HMOM-TPHAP (manufactured by Honshu Chemical Industry Co., Ltd.) Component (G-2): YX-4000H (manufactured by Mitsubishi Chemical Corporation) Solvent: GBL: gamma butyrolactone PGMEA: propylene glycol monomethyl ether acetate.

[0378]

[0379] Table 1 shows the formulation of a resin composition composed of (A) resin, (B) photosensitizer, and (C) colorant. Resin composition 1-21 was prepared using the solvent shown in Table 1 so that the solids concentration was 40% by mass. Tables 2-1 and 2-2 show the resin compositions used in the examples, the light transmittance (%) of the cured film of the resin composition at a wavelength of 450 nm and a standard thickness of 5 μm, the total thickness (μm) of the cured film, the number of layers of the cured film, the shape and length of the opening pattern processed in the cured film, and the angle of the inclined side of the opening pattern.

[0380]

[0381]

[0382]

[0383] Regarding the evaluation level (1), among the display devices, those in which the glare of the wiring was suppressed and concealed by the cured film and the longest length of the opening pattern was 2 μm or less were rated as level A; among the display devices, those in which the glare of the wiring was suppressed and concealed by the cured film and the longest length of the opening pattern was 5 μm or less were rated as level B; among the display devices, those in which the glare of the wiring was suppressed and concealed by the cured film and the longest length of the opening pattern was 20 μm or less were rated as level C; among the display devices, those in which the glare of the wiring was suppressed and concealed by the cured film and the longest length of the opening pattern was more than 20 μm were rated as level D; and among the display devices, those in which the wiring could be clearly confirmed visually by the cured film were rated as level E.

[0384] Regarding the evaluation level (2), the angle of the inclined side was evaluated as level A when it was 55° or more and 80° or less, level B when it was 40° or more and less than 55° or more than 80° and 85° or less, and level C when it was less than 40° or more than 85°.

[0385] (Embodiment 1) (Configuration of FIG. 7) An embodiment of a display device of the present invention will be described with reference to the cross-sectional view of FIG. 7 taken along a plane perpendicular to the support substrate or counter substrate, which shows the manufacturing process.

[0386] As shown in Figure 7a, a glass substrate was used as the support substrate 18. A temporary bonding material made of polyimide was placed on the glass substrate, and ITO was formed as wiring 4d on a portion of the surface of the temporary bonding material by sputtering. Then, a light-emitting element 2, which is a light-emitting element, was placed on the support substrate 18 (corresponding to step (D1)). The light-emitting element 2 had a thickness of 7 μm, one side length of 30 μm, and the other side length of 50 μm.

[0387] Next, as shown in Figure 7b, resin composition 1 described in Table 1 was applied onto the support substrate 18 and the light-emitting element 2 so that the thickness would be 10 μm after heat treatment, thereby forming a resin film 19 (corresponding to process (D2)).

[0388] Next, as shown in Fig. 7c, the resin film 19 was irradiated with i-line (365 nm) light through a mask having a desired pattern. The exposed resin film 19 was developed using a 2.38 mass % tetramethylammonium (TMAH) aqueous solution to form a plurality of opening patterns 12 penetrating the resin film 19 in the thickness direction (corresponding to step (D3)). The opening patterns were circular, and the longest length of the bottom surface of the smallest region of the opening pattern was 2 µm in diameter.

[0389] Next, the resin film 19 was heat-treated at 110° C. for 30 minutes in an atmosphere with an oxygen concentration of 100 ppm or less, and then further heat-treated at 230° C. for 60 minutes to be cured, thereby forming a cured film 3 having a thickness of 10 μm (corresponding to step (D4)).

[0390] Next, as shown in Fig. 7d, a titanium barrier metal was sputtered onto the cured film 3, and a copper seed layer was further formed thereon by sputtering. After that, a photoresist layer was formed, and then copper wiring 4 electrically connected to the light-emitting element 2 was formed on the opening pattern 12 of the cured film 3 and on a portion of the surface of the cured film 3 by plating. Then, the photoresist, seed layer, and barrier metal were removed (corresponding to step (D5)). The thickness of the wiring 4a formed on the portion of the surface of the cured film 3 was 5 µm.

[0391] 7e-7f, steps (D2), (D3), (D4), and (D5) were then repeated twice to form three layers of cured film 3. As a result, the total thickness of the three layers of cured film 3 was 30 μm.

[0392] Next, as shown in FIG. 7g, a barrier metal 9 was formed by sputtering in the opening pattern 12 of the cured film 3, forming bumps 10. Then, as shown in FIG. 7h, the solder was reflowed at 260°C for 1 minute, and electrically connected to a light-emitting element drive substrate 7 having a driver IC (drive element 8) via the bumps 10. The support substrate 18 was then peeled off, and an opposing substrate 5 was attached using an adhesive or the like, thereby obtaining a display device 1 having a plurality of light-emitting elements 2. Note that a glass substrate with copper wiring was used as the light-emitting element drive substrate 7, and wiring 4c was used on its side as shown in FIG. 7h. The photosensitive conductive paste 1 of Preparation Example 1 was used as wiring 4c (corresponding to step D9). The wiring 4c was produced as follows.

[0393] <Preparation of wiring 4c using photosensitive conductive paste 1 of Preparation Example 1> Photosensitive conductive paste 1 was applied to a release PET film having a thickness of 16 μm and a release agent applied thereto, so that the film thickness after drying would be 6.0 μm, and the resulting coating film was dried for 10 minutes in a drying oven at 100° C. Thereafter, an exposure device having an ultra-high pressure mercury lamp was used to expose the wiring 4c to 350 mJ / cm. ２ After exposure at an exposure dose of 1000 ppm, the film was spray-developed using a 0.1% by mass aqueous sodium carbonate solution as a developer at a pressure of 0.1 MPa for 30 seconds to obtain a pattern. The resulting pattern was then cured in a drying oven at 140°C for 30 minutes to obtain a transfer sample with wiring. The resulting pattern had a line width of 50 μm and a line length of 90 mm. The transfer sample was bonded to both sides so that a portion of the wiring was located at the edge of the glass having the R-chamfered portion, and the side surface of the glass was pressed against a hot plate at 130°C for 30 seconds. The remaining portion was then transferred using a hot roll laminator at 130°C and 1.0 m / min.

[0394] Example 2 A display device 2 was obtained in the same manner as in Example 1, except that the resin composition 1 in Example 1 was changed to a resin sheet made of resin composition 2, and a resin film 19 was formed by lamination.

[0395] Examples 3 to 14 Display devices 3 to 14 were obtained in the same manner as in Example 1, except that resin composition 1 in Example 1 was changed to resin compositions 3 to 14.

[0396] (Example 15) In Example 1, resin composition 1 was applied onto supporting substrate 18 and light-emitting element 2 so that the thickness after heat treatment would be 20 μm to form resin film 19. As a result, a display device 15 was obtained in the same manner as in Example 1, except that the total thickness of three-layer cured film 3 became 40 μm.

[0397] Example 16 An example of a display device of the present invention will be described with reference to the cross-sectional view of a plane perpendicular to the support substrate or counter substrate, which shows the fabrication process in Figure 8. First, as shown in Figure 8a, copper pads 17 were placed on support substrate 18 (corresponding to step (E1)). The pads had a thickness of 0.2 µm. Next, as shown in Figure 8b, resin composition 2 listed in Table 1 was applied to support substrate 18 and pads 17 so that the thickness after heat treatment was 10 µm, forming resin film 19 (corresponding to step (E2)).

[0398] Next, as shown in FIG. 8c, a plurality of opening patterns 12 were formed in the resin film 19 under the same conditions as in the photolithography step shown in Example 1 (corresponding to step (E3)).

[0399] Next, the resin film 19 was cured under the same conditions as in Example 1 to form a cured film 3 having a thickness of 10 μm (corresponding to step (E4)).

[0400] Next, in FIG. 8c, in order to improve the adhesion between the cured film 3 and the wiring 4, a barrier metal such as titanium was sputtered on the cured film 3, and a copper seed (seed layer) was further formed on top of that by sputtering.

[0401] Next, as shown in Fig. 8d, a photoresist layer was formed, and then wiring 4 made of copper was formed by plating on the opening pattern 12 of the cured film 3 and on a portion of the surface of the cured film 3 (corresponding to step (E5)). The thickness of the wiring 4 formed on the portion of the surface of the cured film 3 was 5 µm. Thereafter, the photoresist, seed layer, and barrier metal were removed.

[0402] Thereafter, steps (E2), (E3), (E4), and (E5) were repeated twice to form three layers of cured films 3 having wiring 4 therein, as shown in Fig. 8e. As a result, the total thickness of the three layers of cured films 3 was 30 µm.

[0403] 8f, the light-emitting element 2 was disposed on the cured film 3 so as to maintain electrical connection with the wiring 4 (corresponding to step (E6)). The thickness of the light-emitting element 2 was 7 μm.

[0404] Next, as shown in Fig. 8g, a resin film 19 made of the resin composition 2 was formed on the light-emitting element 2 and cured by heat treatment to form a cured film 21. After heat treatment at 110°C for 30 minutes in an atmosphere with an oxygen concentration of 100 ppm or less, further heat treatment was performed at 230°C for 60 minutes to form the cured film 21. Thereafter, ITO was formed as wiring 4d on a part of the surface of the cured film 21 by sputtering.

[0405] Next, as shown in Fig. 8h, the support substrate 18 was peeled off, and a light-emitting element drive substrate 7 having a driver IC, which is a drive element 8, was electrically connected via bumps 10. Furthermore, an opposing substrate 5 was attached to the light-emitting elements 2 using an adhesive or the like, thereby obtaining a display device 16 having a plurality of light-emitting elements 2. Note that a glass substrate having copper wiring was used as the light-emitting element drive substrate 7, and wiring 4c was used on its side as shown in Fig. 8h, and the photosensitive conductive paste 1 of Preparation Example 1 was used as the wiring 4c.

[0406] (Example 17) The same procedure as in Example 16 was carried out, except that the resin composition 2 in Example 16 was changed to resin composition 10, and the support substrate 18 was used as the light-emitting element driving substrate 7 on which the wiring 4c was formed, and was used as is without undergoing a peeling process, to obtain a display device 17.

[0407] Example 18 A display device 18 was obtained in the same manner as in Example 16, except that T693 / R4000 Series (manufactured by Nagase ChemteX Corporation) was used as the cured film 21 formed on the light-emitting element 2 and the cured film 21 was formed by heat treatment at 150°C for 60 minutes.

[0408] (Example 19) In the same manner as in Example 15, multiple layers of the cured film 3 shown in FIG. 8e were formed, and then partition walls 15 were formed between and around the light-emitting elements 2 to be arranged later using the resin composition 2 as shown in FIG. 9f (corresponding to step (E9)). Thereafter, multiple light-emitting elements 2 were arranged as shown in FIG. 9g. As shown in FIG. 9h, the support substrate 18 was peeled off, and a light-emitting element drive substrate 7 having a driver IC, which is a drive element 8, was electrically connected via bumps 10. In addition, an opposing substrate 5 was attached to the light-emitting elements 2 using an adhesive or the like, thereby obtaining a display device 19 having multiple light-emitting elements 2. The thickness of the light-emitting elements 2 was 7 μm, and the thickness of the partition walls was 10 μm.

[0409] Example 20 As shown in Fig. 17a, partition walls 15 were formed on a support substrate 18 (corresponding to step D8). Next, as shown in Fig. 17b, light-emitting elements 2 were formed between the partition walls 15 (corresponding to step (D1)). Except for this, a display device 20 was manufactured using the same steps as in Example 3. The light-emitting elements 2 had a thickness of 7 µm, and the partition walls 15 were formed to a thickness of 10 µm. The partition walls 15 were made of a known acrylic resin containing a white pigment.

[0410] (Example 21) A display device 21 was obtained in the same manner as in Example 1, except that the resin composition 1 in Example 1 was changed to resin composition 17, a photoresist was formed before exposure, and the photoresist was removed after development.

[0411] Example 22 A display device 22 was obtained in the same manner as in Example 1, except that the resin composition 1 in Example 1 was changed to the resin composition 18.

[0412] (Example 23) The same procedure as in Example 1 was carried out except that the resin composition 1 in Example 1 was changed to the resin composition 19 and the exposed resin film 19 was developed using cyclopentanone, to obtain a display device 23.

[0413] (Examples 24-25) Resin composition 1 in Example 1 was changed to resin compositions 20-21, and resin composition 1 described in Table 1 was applied onto supporting substrate 18 and light-emitting element 2 so that the thickness would be 8 μm after heat treatment, thereby forming resin film 19 (corresponding to process (D2)).

[0414] 7c, the resin film 19 was irradiated with i-line (365 nm) through a mask having a desired pattern. The exposed resin film 19 was developed using a 2.38 mass % aqueous solution of tetramethylammonium (TMAH), thereby forming a plurality of opening patterns 12 penetrating the resin film 19 in the thickness direction (corresponding to step (D3)).

[0415] Next, the resin film 19 was heat-treated at 110°C for 30 minutes in an atmosphere with an oxygen concentration of 100 ppm or less, and then further heat-treated at 230°C for 60 minutes to be cured, thereby forming a cured film 3 with a thickness of 8 µm (corresponding to step (D4)).

[0416] Next, as shown in Fig. 7d, a titanium barrier metal was sputtered onto the cured film 3, and a copper seed layer was further formed thereon by sputtering. After that, a photoresist layer was formed, and then copper wiring 4 electrically connected to the light-emitting element 2 was formed on the opening pattern 12 of the cured film 3 and on a portion of the surface of the cured film 3 by plating. Thereafter, the photoresist, seed layer, and barrier metal were removed (corresponding to step (D5)). The thickness of the wiring 4a formed on the portion of the surface of the cured film 3 was 2 µm.

[0417] 7e-7f, steps (D2), (D3), (D4), and (D5) were then repeated twice to form three layers of cured film 3. The second and third layers of cured film 3 were formed so that their thicknesses were 4 μm after heat treatment. As a result, the total thickness of the three layers of cured film 3 was 16 μm. Display devices 24-25 were obtained in the same manner as in Example 1 except for the above.

[0418] Example 26 A display device 26 was obtained in the same manner as in Example 16, except that the resin composition 2 in Example 16 was changed to the resin composition 18.

[0419] (Example 27) The same procedure as in Example 16 was carried out except that the resin composition 2 in Example 16 was changed to the resin composition 19 and the exposed resin film 19 was developed using cyclopentanone, to obtain a display device 27.

[0420] (Examples 28 to 29) Resin composition 2 in Example 16 was changed to resin compositions 20 and 21, and as shown in FIG. 8b, resin compositions 20 and 21 were applied onto a support substrate 18 and a pad 17 so that the thickness after heat treatment was 4 μm, thereby forming a resin film 19 (corresponding to step (E2)).

[0421] Next, as shown in FIG. 8c, a plurality of opening patterns 12 were formed in the resin film 19 under the same conditions as in the photolithography step shown in Example 1 (corresponding to step (E3)).

[0422] Next, the resin film 19 was cured under the same conditions as in Example 1 to form a cured film 3 having a thickness of 4 μm (corresponding to step (E4)).

[0423] Next, in FIG. 8c, in order to improve the adhesion between the cured film 3 and the wiring 4, a barrier metal such as titanium was sputtered on the cured film 3, and a copper seed (seed layer) was further formed on top of that by sputtering.

[0424] Next, as shown in Fig. 8d, a photoresist layer was formed, and then wiring 4 made of copper was formed by plating on the opening pattern 12 of the cured film 3 and on a portion of the surface of the cured film 3 (corresponding to step (E5)). The thickness of the wiring 4 formed on the portion of the surface of the cured film 3 was 2 µm. Thereafter, the photoresist, seed layer, and barrier metal were removed.

[0425] Thereafter, steps (E2), (E3), (E4), and (E5) were repeated twice to form three layers of cured film 3 having wiring 4 therein, as shown in FIG. 8e. As a result, the total thickness of the three layers of cured film 3 was 12 μm. Display devices 28 and 29 were obtained in the same manner as in Example 16 except for the above.

[0426] 7h, a TFT substrate was used as the light-emitting element driving substrate 7 in Example 3, and grooves were formed on the side surface of the substrate by laser processing, and titanium and copper were formed in that order by sputtering, and then copper was formed by plating to form wiring 4c (corresponding to step D9).Otherwise, the same method as in Example 3 was used to obtain a display device 30.

[0427] 8h, a TFT substrate was used as the light-emitting element driving substrate 7 in Example 16, and grooves were formed on the side surface of the substrate by laser processing, and titanium and copper were formed in that order by sputtering, and then copper was formed by plating to form wiring 4c (corresponding to step E11).Otherwise, the same method as in Example 16 was used to obtain a display device 31.

[0428] (Example 32) On the side surface of the light-emitting element drive substrate 7 of Example 30, wiring 4c was used as shown in Figure 7h, and the photosensitive conductive paste 1 of Preparation Example 1 was used as the wiring 4c (corresponding to step D9). Except for this, the same method as in Example 30 was carried out to obtain a display device 32.

[0429] 8h, wiring 4c was used on the side surface of light-emitting element drive substrate 7 of Example 31, and photosensitive conductive paste 1 described in Example 32 was used as wiring 4c (corresponding to step E11).Otherwise, the same method as in Example 31 was carried out to obtain display device 33.

[0430] (Example 34) A printed wiring board was used as the light-emitting element driving substrate 7 of Example 30, and the same procedure as Example 30 was carried out except that the wiring 4c was not formed and the driving element 8 and wiring 4 were connected through the wiring in the printed wiring board and the bump 10, to obtain a display device 34.

[0431] (Example 35) A printed wiring board was used as the light-emitting element driving substrate 7 of Example 31, and the same method as Example 31 was used except that the wiring 4c was not formed and the driving element 8 and wiring 4 were connected through the wiring in the printed wiring board and the bump 10, to obtain a display device 35.

[0432] Example 36 As shown in Fig. 18a, a light-shielding layer 25 was formed on a support substrate 18 (corresponding to step D10). Next, as shown in Fig. 18a, a light-emitting element 2 was formed between the light-shielding layers 25 (corresponding to step (D1)). Apart from that, a display device 36 was manufactured using the same steps as in Example 3. The light-shielding layer 25 was manufactured as follows.

[0433] <Preparation of Light-Shielding Layer 25> The colored resin composition 1 was applied to the support substrate 18 so as to have a thickness of 1 μm after heat treatment, and the applied film was heated and dried for 2 minutes on a hot plate at 100° C. This dried film was exposed to ultraviolet light at 200 mJ / cm using an exposure machine having an ultra-high pressure mercury lamp. ２ The film was then developed using an alkaline developer of a 0.045% by mass aqueous solution of potassium hydroxide, followed by rinsing with pure water to obtain a patterned film. The obtained patterned film was post-baked in a hot air oven at 230°C for 30 minutes to obtain a light-shielding layer.

[0434] Example 37 A display device 37 was produced in the same manner as in Example 36, except that the light-shielding layer 25 in Example 36 was changed to the colored resin composition 2 to form the light-shielding layer 25 .

[0435] (Example 38) In Figure 7f, a display device 38 was obtained by the same process as in Example 3, except that the thickness of the wiring 4a in contact with the bump 10 was 10 µm, the thickness of the cured film 3 formed on a part of the surface of the wiring 4a was 15 µm, and the total thickness of the cured film 3 was 35 µm.

[0436] (Example 39) In Figure 8b, a display device 39 was obtained in the same process as in Example 16, except that the thickness of the pad 18 was 10 µm, the thickness of the cured film 3 formed on a part of the surface of the pad was 15 µm, and the total thickness of the cured film 3 was 35 µm.

[0437] Example 40 An example of a display device of the present invention will be described with reference to the cross-sectional view of the fabrication process in Figure 19. As shown in Figure 19a, a TFT array substrate was used as the light-emitting element driving substrate 7, and resin composition 2 described in Table 1 was applied to the light-emitting element driving substrate 7 so that the thickness would be 3 µm after heat treatment, forming a resin film 19 (corresponding to step (F1)). The thickness of the wiring 4 was 1 µm.

[0438] Next, a plurality of opening patterns 12 were formed in the resin film 19 under the same conditions as in the photolithography process shown in Example 2 (corresponding to process (F2)).

[0439] Next, the resin film 19 was cured under the same conditions as in Example 3 to form a cured film 3 having a thickness of 3 μm (corresponding to step (F3)).

[0440] Next, as shown in Figure 19b, the wiring was formed on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film. After forming a photoresist layer (not shown), ITO was formed as wiring 4e on a portion of the surface of the cured film 3 by sputtering. Then, unnecessary photoresist was removed (corresponding to step (F4)). The thickness of the ITO was 0.1 µm.

[0441] 19c, steps (F1), (F2), and (F3) were repeated to cure the resin composition 3 described in Table 1, thereby forming a cured film 3 having a thickness of 3 μm. Thereafter, wiring 4c was formed using the photosensitive conductive paste 1 of Preparation Example 1.

[0442] Next, as shown in FIG. 19d, partition walls 15 were formed on the cured film 3. Next, light-emitting elements 2 were formed between the partition walls 15 (step (corresponding to F5)). The light-emitting elements 2 were formed to a thickness of 7 μm, and the partition walls 15 were formed to a thickness of 8 μm. The partition walls 15 were made of a known acrylic resin containing a white pigment. A resin film 19 made of resin composition 2 was formed on the cured film 3 and the light-emitting elements 2, and cured by heat treatment to form a cured film 21. ITO was formed as wiring 4d on part of the surface of the cured film 3 by sputtering.

[0443] 19e, an opposing substrate 5 was attached using an adhesive. The driving elements 8 such as a driver IC were electrically connected to the light-emitting elements 2 via the wiring 4c and the wiring 4 and wiring 4e extending into the cured film 3, thereby obtaining a display device 40 having a plurality of light-emitting elements 2.

[0444] Examples 41 and 42 Display devices 41 and 42 were obtained in the same manner as in Example 40, except that resin composition 2 in Example 40 was changed to resin compositions 13 and 21.

[0445] (Example 43) A display device 43 was obtained in the same manner as in Example 3, except that a light-emitting element 2 having electrodes on each of its discontinuous surfaces as shown in Figure 22 was used, a temporary bonding material made of polyimide was placed on a glass substrate, and the light-emitting element 2, which is a light-emitting element, was placed on the support substrate 18 on which the temporary bonding material was placed (corresponding to process (D1)).

[0446] Example 44 A display device 44 was obtained in the same manner as in Example 16, except that a light-emitting element 2 having electrodes on each of its discontinuous surfaces as shown in FIG. 23 was used.

[0447] Example 45 A display device 45 was obtained in the same manner as in Example 40, except that a light-emitting element 2 having electrodes on each of its discontinuous surfaces as shown in FIG. 24 was used.

[0448] Example 46 A display device 46 was obtained in the same manner as in Example 25, except that the number of layers of the cured film 3 was one and the total thickness was 5 μm.

[0449] Example 47 A display device 47 was obtained in the same manner as in Example 3, except that the number of layers of the cured film 3 was 5 and the total thickness was 50 μm.

[0450] Example 48 A display device 48 was obtained in the same manner as in Example 3, except that the number of layers of the cured film 3 was four and the total thickness was 60 μm.

[0451] Example 49 A display device 49 was obtained in the same manner as in Example 3, except that the number of layers of the cured film 3 was 11 and the total thickness was 110 μm.

[0452] Example 50 A display device according to the second aspect of the present invention will be described with reference to the cross-sectional view of Figure 29, which is taken along a plane perpendicular to the light-emitting element driving substrate and shows the manufacturing process. As shown in Figure 29a, a TFT array substrate was used as the light-emitting element driving substrate 7, and the resin composition 13 shown in Table 1 was applied to the light-emitting element driving substrate 7 so that the thickness would be 3 μm after heat treatment, forming a resin film 19 (corresponding to step (G1)). The wiring 4 had a thickness of 1 μm. Next, a plurality of opening patterns 12 were formed in the resin film 19 under the same conditions as the photolithography process shown in Example 3 (corresponding to step (G2)).

[0453] Next, the resin film 19 was cured under the same conditions as in Example 3 to form a cured film 3 having a thickness of 3 μm (corresponding to step (G3)).

[0454] Next, as shown in Figure 29b, the wiring was formed on at least a portion of the surface of the cured film and on a portion of the opening pattern of the cured film. After forming a photoresist layer (not shown), ITO was formed as wiring 4e on a portion of the surface of the cured film 3 by sputtering. Then, unnecessary photoresist was removed (corresponding to step (G4)). The thickness of the ITO was 0.1 µm.

[0455] Next, as shown in FIG. 29c, the photosensitive conductive paste 1 of Preparation Example 1 was used to form the wiring 4c.

[0456] Next, as shown in FIG. 29d, partition walls 15 were formed on the cured film 3. Next, light-emitting elements 2 were formed between the partition walls 15 (step (corresponding to G5)). The light-emitting elements 2 were formed to a thickness of 7 μm, and the partition walls 15 were formed to a thickness of 8 μm. The partition walls 15 were made of a known acrylic resin containing a white pigment. A resin film 19 made of resin composition 2 was formed on the cured film 3 and the light-emitting elements 2, and cured by heat treatment to form a cured film 21. ITO was formed as wiring 4d on part of the surface of the cured film 3 by sputtering.

[0457] 29e, an opposing substrate 5 was attached using an adhesive. In addition, a driving element 8 such as a driver IC was electrically connected to the light-emitting element 2 via the wiring 4c and the wiring 4 and wiring 4e extending into the cured film 3, thereby obtaining a display device 52 having a plurality of light-emitting elements 2.

[0458] Example 51 A display device 53 was obtained in the same manner as in Example 50, except that the resin composition 13 in Example 50 was changed to the resin composition 21.

[0459] Example 52 A display device 54 was obtained in the same manner as in Example 50, except that a light-emitting element 2 having electrodes on each of its discontinuous surfaces as shown in FIG. 28 was used.

[0460] Example 53 A display device 55 was obtained in the same manner as in Example 52, except that the resin composition 13 in Example 52 was changed to the resin composition 21.

[0461] As a result, the display devices 1 to 49 and 52 to 55 had sufficiently low light transmittance for the cured film 3, which concealed the wiring 4, suppressed glare from the wiring 4, and made it difficult to see from the outside, thereby enhancing the design. Furthermore, the thickness of the cured film was smaller than that of conventional flexible substrates, which made it possible to suppress wiring defects such as wiring shorts due to a low package height and short wiring distances, reduce loss, and improve high-speed response. Furthermore, the display devices 1 to 20, 22 to 49, 52, and 54 were capable of microfabrication, allowing for the use of minute light-emitting elements and the high-density packaging of light-emitting elements. Furthermore, a cured film made of a resin composition could also be used as the partition 15, and forming the partition facilitated bonding of the opposing substrates. Furthermore, in the display devices 13, 24-25, 28-29, 41-42, and 52-55, the cured film 3 is black, which conceals the wiring 4, suppresses glare from the wiring 4, making it less visible from the outside and enhancing the design. Furthermore, the reduced external light reflection and improved contrast enhance visibility. Furthermore, in the display devices 1-33, 36-49, and 52-55, at least a portion of the wiring 4c extends to the side of the substrate, thereby reducing the height and improving the high-speed response of the display device itself, and further enabling the display device to be made smaller and have a narrower frame. Furthermore, in the display devices 36 and 37, by forming a light-shielding layer between multiple light-emitting elements, it was possible to suppress light leakage from the light-emitting elements and color mixing between pixels, thereby improving contrast, without significantly compromising light extraction efficiency. In display devices 38 and 39, the thickness of the wiring near the bumps 10 was thicker than the thickness of the wiring near the light-emitting elements 2, which prevented wiring defects when connecting the light-emitting element drive substrate 7 using the bumps 10, making it possible to obtain highly reliable display devices. In display devices 46 and 52 to 55, the number of layers of the cured film 3 was one, so the number of light-emitting elements that could be arranged was limited. In display device 49, the thickness of the entire cured film exceeded 100 μm, which reduced the flatness of the steps, causing problems when mounting the light-emitting elements.

[0462] Comparative Examples 1 and 2 Display devices 50 and 51 were obtained in the same manner as in Example 1, except that resin composition 1 in Example 1 was changed to resin compositions 15 and 16.

[0463] As a result, in the display devices 50 to 51, the light transmittance of the cured film 3 was sufficiently high, and therefore the hiding power, including the suppression of glare from the wiring 4 of the cured film 3, was insufficient.

[0464] REFERENCE SIGNS LIST 1 Display device 2 Light-emitting element 3 Cured film 4, 4c, 4d, 4e Wiring 4a Thickness of wiring arranged on the surface of the cured film 4b Thickness of wiring extending in an opening pattern penetrating the cured film in the thickness direction 5 Counter substrate 6 Electrode 7 Light-emitting element driving substrate 8 Driving element 9 Barrier metal 10 Bump 11a Designated area A 11b Designated area B 12 Opening pattern 13 Bottom portion of wiring 4 14 Longest length of bottom portion 15 Partition wall 16 External substrate 17 Pad 18 Support substrate 19 Resin film 20 Total thickness of cured film 21 Cured film 22 TFT 23 TFT insulating layer 24 Contact hole 25 Light-shielding layer 26 Inclined side 27 Angle of inclined side 28 Thickness of cured film 3 29 Position at 1 / 2 thickness of effect film 3

Claims

1. A display device having at least wiring, a cured film, and a plurality of light-emitting elements, wherein each light-emitting element has electrodes on two different surfaces, at least one of the electrodes is connected to a plurality of wirings extending in the cured film, the plurality of wirings are configured to maintain electrical insulation by the cured film, the cured film is a film obtained by curing a resin composition containing (A) resin, the transmittance of light at a wavelength of 450 nm at a thickness of 1 μm of the cured film is 0.1% or more and 95% or less, and the resin composition containing (A) resin further contains (B) a photosensitive agent.

2. The display device according to claim 1, wherein the transmittance of light at a wavelength of 450 nm at a thickness of 5 μm of the cured film is 0.1% or more and 79% or less.

3. The display device according to claim 1, wherein the transmittance of light at a wavelength of 450 nm at a thickness of 1 μm of the cured film is 0.1% or more and 25% or less.

4. The display device according to claim 1 or 2, wherein the total thickness of the cured film is 5 μm or more and 100 μm or less.

5. The display device according to claim 1 or 2, wherein the number of layers of the cured film is two or more and ten or less.

6. The display device according to claim 1 or 2, wherein the cured film is provided with an opening pattern that penetrates in the thickness direction, and the wiring is arranged in at least the opening pattern, and the longest length of the bottom surface portion of the wiring formed in contact with the light-emitting element is 2 μm or more and 20 μm or less.

7. The display device according to claim 1 or 2, wherein the cured film covers a surface other than the light extraction surface of the light-emitting element.

8. A display device comprising at least a substrate having wiring and / or TFTs, a cured film, and a plurality of light-emitting elements, wherein each light-emitting element has electrodes on two different surfaces, at least a portion of the wiring and / or TFTs is in contact with the cured film, the cured film is a film obtained by curing a resin composition containing (A) resin, the transmittance of light at a wavelength of 450 nm at a thickness of 1 μm of the cured film is 0.1% or more and 95% or less, and the resin composition containing (A) resin further contains (B) a photosensitive agent.

9. The display device according to claim 1 or 8, wherein a partition wall having a thickness greater than or equal to the thickness of the light-emitting element is provided between a plurality of the light-emitting elements.

10. The display device according to claim 1 or 8, wherein the light-emitting element is an LED with a side length of 5 μm or more and 700 μm or less.

11. The display device according to claim 1 or 8, further comprising a driving element and a substrate, wherein the driving element is connected to the light-emitting element via wiring, and at least a portion of the wiring extends to the side surface of the substrate.

12. The display device according to claim 1 or 8, further comprising a light-shielding layer between a plurality of light-emitting elements.

13. The display device according to claim 1 or 8, wherein the resin (A) contains one or more resins selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, polybenzoxazole precursor, and copolymers thereof.

14. The display device according to claim 1 or 8, wherein the resin composition containing the resin (A) further contains a colorant (C), and the colorant (C) contains a colorant having an absorption maximum in the wavelength range of 400 nm or more and 490 nm or less.

15. The display device according to claim 1 or 8, wherein the resin composition containing the resin (A) further contains a colorant (C), and the colorant (C) contains a colorant having an absorption maximum in the range of wavelengths greater than 490 nm and less than or equal to 580 nm.

16. The display device according to claim 1 or 8, wherein the resin composition containing the resin (A) further contains a colorant (C), and the colorant (C) contains a colorant having an absorption maximum in the range of wavelengths greater than 580 nm and less than or equal to 800 nm.

17. The display device according to claim 1 or 8, wherein the (C) coloring agent further comprises (C-1) a coloring agent having an absorption maximum in the range of wavelengths 400 nm or more and 490 nm or less, (C-2) a coloring agent having an absorption maximum in the range of wavelengths greater than 490 nm and 580 nm or less, and (C-3) a coloring agent having an absorption maximum in the range of wavelengths greater than 580 nm and 800 nm or less.

18. The display device according to claim 1 or 8, wherein the resin composition containing the resin (A) is positive-type photosensitive.