DISPLAY DEVICE

An organic EL display device includes an array substrate provided with a plurality of organic EL elements, a counter substrate facing the array substrate, and a sealing member configured to bond together the array substrate and the counter substrate. The sealing member includes, between the array substrate and the counter substrate, a dam member disposed surrounding a display region and a fill member filling a sealed space surrounded by the dam member. A panel body formed by bonding together the array substrate and the counter substrate includes a partition wall configured to partition the dam member and the fill member and a plurality of spacers configured to maintain a gap between the array substrate and the counter substrate.

TECHNICAL FIELD

The disclosure relates to a display device.

BACKGROUND ART

In recent years, organic electro luminescence (hereinafter, referred to as EL) display devices using organic EL elements have been used as light-emitting elements in practical applications. Also, development in continuing for quantum-dot light emitting diode (QLED) display devices provided with QLEDs that are light-emitting elements using a quantum dot-including layer. Organic EL display devices and QLED display devices have a sealing structure in which a plurality of light-emitting elements constituting a display region are covered with a sealing member having barrier properties in order to suppress deterioration of the plurality of light-emitting elements due to moisture, oxygen, and the like entering. A known sealing structure for such a light-emitting element includes a dam fill structure. A dam fill structure is disclosed in PTL 1, for example.

An organic EL display device (OLED display panel) of PTL 1 includes a first substrate and a second substrate facing one another and a dam member (first package gel), a fill member (second package gel), and a cover wall provided between the first substrate and the second substrate. The dam member is formed around the sealed space between the first substrate and the second substrate. The fill member fills the sealed space formed by the dam member. A plurality of the cover walls are provided on the first substrate aligned with the dam member in the sealed space.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In the dam fill structure as disclosed in PTL 1, adjacent cover walls are disposed with a gap therebetween. Further, a gap is provided between each cover wall and the second substrate. Thus, if the pressure when bonding together the first substrate and the second substrate with the dam member and the fill member therebetween is high, the speed of the fill member when spreading from the central side to the outer peripheral side increases when the fill member spreads between adjacent cover walls and the gaps between the cover walls and the second substrate. Thus, the fill member may push out the dam member from the inside and cause it to break.

In addition, it is difficult to make the gap between the first substrate and the second substrate constant when the two substrates are bonded together. Thus, the volume of the sealed space surrounded by the dam member between the first substrate and the second substrate is not constant. When the amount of the fill member is large with respect to the volume of the sealed space in which the variation is likely to occur, the fill member may cause the dam member to break. On the other hand, when the amount of the fill member is small with respect to the volume of the sealed space, there is a possibility of air bubbles formed inside the sealed space. When the dam member breaks or air bubbles are formed in the sealed space, the sealing properties of the light-emitting element from the dam fill structure are impaired.

An object of the disclosure is to suppress impairment of the sealing properties of a light-emitting element from a dam fill structure in a display device.

Solution to Problem

A target of the technique according to the disclosure is a display device. A display device according to a technique of the disclosure includes a first substrate provided with a plurality of light-emitting elements;a second substrate disposed facing the first substrate; and a sealing member configured to bond together the first substrate and the second substrate and seal the plurality of light-emitting elements. The display device includes a display region for displaying an image by light emission of the plurality of light-emitting elements and a frame region provided on an outer side the display region. The sealing member includes, between the first substrate and the second substrate, a dam member disposed in the frame region surrounding the display region and a fill member filling the space surrounded by the dam member. A panel body formed by bonding together the first substrate and the second substrate with the sealing member includes a partition wall configured to partition the dam member and the fill member and a plurality of spacers disposed in a spread-out manner in the display region and configured to maintain a gap between the first substrate and the second substrate.

Advantageous Effects of Invention

According to a technique of the disclosure, impairment of the sealing properties of a light-emitting element from a dam fill structure in a display device can be suppressed.

DESCRIPTION OF EMBODIMENTS

Exemplary embodiments will be described below in detail with reference to the drawings. In the embodiments described below, an organic EL display device is described as an example of a display device according to a technique of the disclosure. Note that the drawings are for schematically describing the techniques of the disclosure. Thus, in the drawings, the dimensions, ratios, and numbers may be exaggerated or simplified to facilitate understanding of the techniques of the disclosure.

In the following embodiments, a “row direction” means the horizontal direction of a screen of a display device. The “row direction” corresponds to a first direction. A “column direction” means a vertical direction of the screen of the display device. The “column direction” corresponds to a second direction. A row of constituent elements such as subpixels means a horizontal arrangement of a plurality of constituent elements forming a line in the row direction. A column of constituent elements such as subpixels means a vertical arrangement of a plurality of constituent elements forming a line in the column direction.

In the following embodiments, the description that a constituent element such as another film, layer, or element is provided or formed on a constituent element such as a certain film, layer, or element does not mean only a case where another constituent element is present immediately above the certain constituent element but also includes a case where a constituent element such as still another film, layer, or element is interposed between both the constituent elements.

In the following embodiments, the description that a constituent element such as a certain film, layer, or element is connected to a constituent element such as another film, layer, or element means that the certain film, layer, or element is electrically connected unless otherwise specified. This description includes, without departing from the gist of the technique of the disclosure, not only a case in which a constituent element is directly connected to another constituent element but also a case in which a constituent element and another constituent element are indirectly connected to each other with still another constituent element such as still another film, layer, element, or the like interposed therebetween. The description also includes a case where another constituent element is integrated with a certain constituent element, that is, a part of the certain constituent element constitutes the other constituent element.

In the following embodiments, a description that a constituent element such as a certain film, layer, or element is in the same layer as a constituent element such as another film, layer, or element means that the certain constituent element is formed by the same process as that of the other constituent element. A description that a constituent element is in a lower layer below a constituent element means that the certain constituent element is formed by a process earlier than that of the other constituent element. A description that a constituent element is in an upper layer above a constituent element means that the certain constituent element is formed by a process later than that of the other constituent element.

In the following embodiments, the description that a constituent element such as a certain film, layer, or element is the same as or equivalent to a constituent element such as another film, layer, or element does not only mean a state where the certain constituent element is completely the same as or completely equivalent to the other constituent element, an also includes a state where the certain constituent element is substantially the same as or substantially equivalent to the other constituent element, such as a state where the certain constituent element and the other constituent element vary within a range of manufacturing modified examples or tolerances.

In the following embodiments, the descriptions of first, second, third, . . . are used to distinguish the words and phrases to which these descriptions are given, and no limitation with regard to the number and order of the words and phrases is intended.

First Embodiment

An organic EL display device1of the first embodiment is used as a display in various devices such as a mobile phone including multifunctional mobile phones such as smartphones and tablet terminals, a personal computer (PC), and a television device.

Configuration of Organic EL Display Device

As illustrated inFIGS.1and2, the organic EL display device1includes an array substrate3, a counter substrate5, and a sealing member7. The array substrate3is an example of a first substrate. The array substrate3includes a plurality of organic electroluminescence elements (organic EL elements)30. The counter substrate5is an example of a second substrate. The array substrate3and the counter substrate5are disposed facing one another. The array substrate3and the counter substrate5are bonded together via the sealing member7and form a panel body PL.

The sealing member7includes a dam member9and a fill member11. The dam member9is disposed on the outer peripheral side of a frame region FA around a display region DA between the array substrate3and the counter substrate5. A sealed space Sc surrounded by the dam member9is formed between the array substrate3and the counter substrate5. The fill member11is filled in the sealed space Sc and fills the air gap between the array substrate3and the counter substrate5.

The dam member9and the fill member11bond the array substrate3and the counter substrate5to seal the plurality of organic EL elements30. Both the dam member9and the fill member11are made of an organic resin material. The organic resin material used for the dam member9and the fill member11is, for example, an epoxy resin, and has a photo-curable properties in that it is cured by irradiation of ultraviolet light or the like. The barrier properties of the dam member9with respect to moisture and oxygen is better than the barrier properties of the fill member11with respect to moisture and oxygen. As the organic resin material used for the dam member9and the fill member11, an acrylic resin, a silicone resin, a fluorine resin, or the like may be used.

The panel body PL is provided with a partition wall12and a plurality of spacers15.

The partition wall12is a wall body that partitions the dam member9and the fill member11and dams up the fill member11together with the dam member9. The partition wall12extends along the inner periphery of the dam member9and is located on the outer periphery of the fill member11. The partition wall12of the present example is formed in a closed frame shape extending around the entire periphery of the frame region FA. The partition wall12is formed, for example, in a rectangular frame-like shape. The partition wall12is provided at least on the counter substrate5.

The partition wall12of the present example is provided separately for the array substrate3and the counter substrate5. The partition wall12is constituted by a first partition wall13and a second partition wall14. The first partition wall13is the partition wall12provided on the array substrate3. The second partition wall14is the partition wall12provided on the counter substrate5. The first partition wall13and the second partition wall14are butted against one another in the direction in which the array substrate3and the counter substrate5face one another.

Each of the plurality of spacers15is a column-like member that maintains the gap between the array substrate3and the counter substrate5. The plurality of spacers15are disposed in a spread-out manner in a predetermined pattern in the display region DA. The plurality of spacers15are disposed in a matrix shape at equal intervals, for example. Each spacer15is provided on one or both of the array substrate3and the counter substrate5where the partition wall12is provided.

Each spacer15of the present example is provided separately for the array substrate3and the counter substrate5. Each spacer15is constituted by a first spacer16and a second spacer17. The first spacer16is the spacer15provided on the array substrate3. The second spacer17is the spacer15provided on the counter substrate5. The first spacer16and the second spacer17are butted against one another in the direction in which the array substrate3and the counter substrate5face one another.

The organic EL display device1includes a wiring line substrate CB in addition to the panel body PL. The wiring line substrate CB is a Flexible Printed Circuit (FPC), for example. The wiring line substrate CB is used to connect an external circuit such as a display control circuit to the panel body PL. The panel body PL includes the display region DA and the frame region FA.

The display region DA is a region for displaying an image and constitutes a screen. An image in the display region DA is displayed via light emission by the plurality of organic EL elements30. The display region DA is provided in a rectangular shape. In the present embodiment, the display region DA having a rectangular shape is used as an example, but the display region DA may have a substantially rectangular shape such as a shape in which at least one side is arc-shaped, a shape in which at least one corner portion is arc-shaped, or a shape having a cutout in a part of at least one side.

As illustrated inFIG.3, the display region DA includes a plurality of pixels PX. The plurality of pixels Ps includes three subpixels. The three subpixels Ps correspond to, for example, a subpixel Pr that emits red light, a subpixel Pg that emits green light, and a subpixel Pb that emits blue light. The subpixels Pr, Pg, and Pb of the three colors forming each pixel PX of the present example are arranged in stripes adjacent to one another in the row direction.

The frame region FA is a region not for displaying an image and constitutes a non-display portion that is not a screen. The frame region FA is provided in a rectangular frame-like shape on the outer side of the display region DA. A portion constituting one side (lower side inFIG.1) of the frame region FA constitutes a terminal region TA. The terminal region TA is provided in a region of the array substrate3protruding from the counter substrate5in a plan view. The wiring line substrate CB is connected to the terminal region TA.

Although not illustrated, a drive circuit is monolithically provided in the frame region FA. In the frame region FA, the drive circuit is disposed in portions constituting the sides (left and right sides inFIG.1) adjacent to the side where the terminal region TA is provided. The drive circuit includes a gate driver. On the wiring line substrate CB, a source driver is mounted as an IC chip.

The frame region FA is further provided with a first frame line and a second frame line. The first frame line and the second frame line are provided on the array substrate3around the display region DA and extend to the terminal region TA. A high-level power supply voltage (ELVDD) is supplied to the first frame line via the wiring line substrate CB. A low-level power supply voltage (ELVSS) is supplied to the second frame line via the wiring line substrate CB.

Array Substrate

As illustrated inFIG.2, the array substrate3includes a base substrate18and an element layer20.

The base substrate18is a plate body forming the base of the array substrate3. The base substrate18is, for example, a glass substrate. The base substrate18may be formed of an organic resin material such as a polyimide resin, a polyamide resin, or an epoxy resin. The base substrate18may have a layered structure in which an inorganic insulating layer including an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride and a resin layer including an organic resin material as described above are layered.

The element layer20includes various kinds of wiring lines21. As illustrated inFIG.3, a plurality of gate lines21g, a plurality of source lines21s, and a plurality of power source lines21pare provided as the wiring lines21.

Each of the plurality of gate lines21gis a wiring line that transmits a gate signal. In the display region DA, the plurality of gate lines21gextend in parallel to one another in a row direction Dx between the subpixels Ps adjacent to one another in a column direction Dy and are arranged at intervals in the column direction Dy. The gate lines21gare provided per row of the subpixels Ps. Each of the gate lines21gis connected to a gate driver included in the drive circuit.

Each of the plurality of source lines21sis a wiring line that transmits a source signal. In the display region DA, the plurality of source lines21sextend in parallel to one another in the column direction Dy between the subpixels Ps adjacent to one another in the row direction Dx and are arranged at intervals in the row direction Dx. The source lines21sare provided per column of the subpixels Ps. Each source line21sis connected to the source driver via the wiring line substrate CB.

Each of the plurality of power source lines21papplies a predetermined high-level power supply voltage (ELVDD). In the display region DA, the plurality of power source lines21pextend in parallel to one another in the column direction Dy between the subpixels Ps adjacent to one another in the row direction Dx and are arranged at intervals in the row direction Dy. The power source lines21pare provided per row of the subpixels Ps. Each power source line21pis connected to the first frame line.

The gate lines21g, the power source lines21p, and the source lines21sintersect one another intermediated by an insulating film. The gate lines21g, the source lines21s, and the power source lines21pextend in a lattice pattern as seen overall in a plan view. For example, the gate lines21g, the source lines21s, and the power source lines21pare made of a metal such as aluminum (Al), tungsten (W), molybdenum (Mo), tantalum (Ta), chromium (Cr), titanium (Ti), copper (Cu), or the like.

As illustrated inFIG.4, the element layer20further includes a base coat film23, a plurality of thin film transistors (hereinafter referred to as TFTs)25, a plurality of capacitors27, a flattening film29, the organic EL elements30, and an edge cover40. The organic EL elements30are examples of light-emitting elements.

The base coat film23is provided over the entire front face of the base substrate18. The base coat film23is formed of an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride, for example. The base coat film23may be a single-layer film made of an inorganic insulating material or may be a layered film.

The plurality of TFTs25are elements for controlling light emission of the organic EL elements30. Each TFT25is configured as a bottom gate type, for example. Although not illustrated, each TFT25includes a gate electrode, a first terminal electrode, and a second terminal electrode. The plurality of TFTs25include a first TFT25A and a second TFT25B. The first TFT25A and the second TFT25B are provided for each subpixel Ps.

The gate electrode of the first TFT25A is connected to the corresponding gate line21g. The first terminal electrode of the first TFT25A is connected to the corresponding source line21s. The gate electrode of the second TFT25B is connected to the second terminal electrode of the first TFT25A. The first terminal electrode of the second TFT25B is connected to the power source line21p. The second terminal electrode of the second TFT25B is connected to the corresponding organic EL element30(pixel electrode31).

Each of the plurality of capacitors27is an element for holding data. At least one capacitor27is provided for each subpixel Ps. Although not illustrated, the capacitor27includes a first capacitance electrode and a second capacitance electrode. The first capacitance electrode and the second capacitance electrode face one another with an insulating film therebetween. The first capacitance electrode is connected to the gate electrode of the first TFT25A. The second capacitance electrode is connected to the second terminal electrode of the second TFT25B.

The plurality of organic EL elements30are each configured as a top-emitting type that extract light produced by an organic EL layer33from the counter substrate5side. The organic EL element30includes the pixel electrode31, the organic EL layer33, and a common electrode35.

The pixel electrode31is provided for each of the subpixels Ps. Each of the plurality of organic EL elements30includes the pixel electrode31individually. The pixel electrodes31are arranged in a matrix shape corresponding to the subpixels Ps. The pixel electrodes31are provided on the flattening film29. The pixel electrodes31have light-reflecting characteristics. The pixel electrodes31function as an anode electrode. A conductive material having a large work function is preferably used for the pixel electrodes31.

The edge cover40is provided to partition the plurality of pixel electrodes31. The edge cover40is formed in a lattice pattern as a whole and covers a peripheral portion of each of the pixel electrodes31. Openings41for respectively exposing the pixel electrodes31are formed in the edge cover40. The edge cover40is made of, for example, an organic resin material such as a polyimide resin or an acrylic resin or a polysiloxane based SOG material or the like.

The organic EL layer33is provided on the individual pixel electrodes31in each opening41of the edge cover40. The organic EL layer33includes a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer that are provided in order on the pixel electrode31. These function layers are made of a known compound suitable for the respective function. One or more of the plurality of function layers may be continuously provided in common in the plurality of subpixels Ps.

The common electrode35is continuously provided in common to the plurality of subpixels Ps. The common electrode35is provided on the organic EL layer33covering the edge cover40and overlaps each of the pixel electrodes31via the organic EL layer33. The common electrode35has light-transmitting characteristics. The common electrode35functions as a cathode electrode. A conductive material having a small work function is preferably used for the common electrode35. The common electrode35extends to the frame region FA and is connected to the second frame line. As illustrated by the two-dot dash line inFIG.3for the sake of convenience, an opening37is formed in the common electrode35at a position corresponding to each first spacer16.

The array substrate3further includes the first partition wall13and the plurality of first spacers16described above. The first partition wall13and each first spacer16are formed of the same material of the edge cover40and in the same layer.

The first partition wall13constitutes a half body obtained by dividing the partition wall12in the thickness direction of the panel body PL. The first partition wall13is formed to have the same height as that of each first spacer16on the array substrate3. An abutting face13sof the first partition wall13and an abutting face16sof each first spacer16are aligned at the same height position in a planar direction orthogonal to the thickness direction of the array substrate3.

Each first spacer16includes a projection formed by protruding portion of the edge cover40. The projection portion is located in the opening37of the common electrode35. The heights of the plurality of first spacers16are all equal to one another. The first spacers16are provided at intersection portions between the vertical line portions and the horizontal line portions of the edge cover40. The area of the abutting face16sof the first spacer16is larger than the area of an abutting face17sof the second spacer17. The abutting face16sof the first spacer16functions as a seating face of the second spacer17.

Counter Substrate

As illustrated inFIG.2, the counter substrate5includes a base substrate45and the second partition wall14and the plurality of second spacers17described above. The second partition wall14and each second spacer17are formed of the same material and in the same layer.

The base substrate45is a plate body corresponding to the base of the counter substrate5. The base substrate45is, for example, a glass substrate. The base substrate45may be formed of an organic resin material such as a polyimide resin, a polyamide resin, or an epoxy resin. The base substrate45may have a layered structure in which an inorganic insulating layer including an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride and a resin layer including an organic resin material as described above are layered.

The second partition wall14constitutes a half body obtained by dividing the partition wall12in the thickness direction of the panel body PL. The second partition wall14is formed to have the same height as that of each second spacer17on the counter substrate5. An abutting face14sof the second partition wall14and the abutting face17sof each second spacer17are aligned at the same height position in a planar direction orthogonal to the thickness direction of the counter substrate5.

The second spacers17are provided in a one-to-one correspondence with the first spacers16of the array substrate3. Each second spacer17is located at a position corresponding to the first spacer16. In other words, the second spacers17are disposed at intersection portions between the vertical line portions and the horizontal line portions of the edge cover40. The heights of the plurality of second spacers17are all equal to one another. The plurality of second spacers17are separated from one another. The plurality of second spacers17may be constituted by projection portions of a resin film provided on the base substrate45and may be connected to one another at a lower portion of the resin film.

Manufacturing Method of Organic EL Display Device

The manufacturing method of the organic EL display device1includes a first substrate preparing process, a second substrate preparing process, a bonding process, and an additional process.

First Substrate Preparing Process

In the first substrate preparing process, the array substrate3is prepared. In order to prepare the array substrate3, the base substrate18, a glass substrate for example, is prepared and the element layer20including the plurality of TFTs25, a plurality of organic EL elements30, and a drive circuit is formed on the base substrate18using a known technique such as photolithography, a vacuum vapor deposition technique, an ink-jet method, or the like.

When the edge cover40is formed, a photosensitive resin material is applied on the substrate where the plurality of pixel electrodes31are formed by a known application method such as a spin coating method or a slit coating method (seeFIG.5; inFIG.5, a portion corresponding to the element layer20with an unformed layer above the pixel electrode31is illustrated as the element layer20for the sake of convenience). As the photosensitive resin material, a positive-type or negative-type photoresist can be used. In the present example, as the photosensitive resin material, a positive-type photoresist is used. Next, an application film100of the photosensitive resin material is pre-baked at a predetermined temperature.

Subsequently, as illustrated inFIG.5, an exposure treatment is performed on the application film100of the photosensitive resin material. In the exposure treatment, the application film100is irradiated with light L such as ultraviolet light using a photomask200. The photomask200is configured to shield a pattern portion where the application film100is to remain and expose an unnecessary portion where the application film100is to be removed. In the exposure treatment of the present example, a graytone mask or a halftone mask is used as the photomask200, the region of the application film100where the first partition wall13and the first spacers16are formed is shielded from light, and the region of the edge cover40where the portion other than the first spacers16is formed is exposed with a smaller amount of light than the portion where the first partition wall13, the first spacers16, and the edge cover40are not formed.

In a case where a negative-type photoresist is used as the photosensitive resin material forming the application film100, in the exposure treatment, the photomask used is configured to expose a pattern portion where the application film100is to remain and to shield an unnecessary portion where the application film100is to be removed. In this case, a graytone mask or a halftone mask is used as the photomask, the region of the application film100where the first partition wall12and the first spacers16are formed is exposed to light, and the region of the edge cover40where the portion other than the first spacers16is formed is shielded from a smaller amount of light than the portion where the first partition wall13, the first spacers16, and the edge cover40are not formed.

Subsequently, the application film100subjected to the exposure treatment is subjected to post-exposure baking to complete the photosensitive reaction of the photosensitive resin material forming the application film100. Subsequently, a development treatment is performed on the application film100in which the photosensitive reaction is completed. In the development treatment, an alkaline developing solution such as tetramethylammonium hydroxide (TMAH) or potassium hydroxide (KOH) is used to dissolve an unnecessary portion of the application film100and leave only a pattern portion of the application film100. Then, after cleaning with pure water, the substrate with the application film100partially left thereon is post-baked at a predetermined temperature to evaporate the solvent remaining on the substrate and completely cure the photoresist. In this manner, as illustrated inFIGS.6and7, the first partition wall13and the plurality of first spacers16are formed on the base substrate18together with the element layer20.

Thereafter, on the substrate where the first partition wall13and the like are formed, a conductive film is formed as a single layer or multilayer by an application method such as an ink-jet method or a slit coating method or a vacuum vapor deposition technique to form the common electrode35. In a case where an ink-jet method is used, the common electrode35including the openings37can be formed by applying silver nanowires or the like so as not to cover the first spacers16. In a case where a slit coating method or a vacuum vapor deposition technique is used, a photoresist is formed at a portion where the conductive film is to be left by screen printing or a lift-off method, the conductive film covering the first spacers16is removed by dry etching or wet etching, and then the photoresist is peeled off. In this manner, the conductive film is patterned and the common electrode35including the openings37is formed. If the thickness of the common electrode35is very thin and there is no problem in bonding the array substrate3and the counter substrate5, the openings37may not be provided in the common electrode35(that is, the conductive film forming the common electrode35may not be patterned).

In this manner, the array substrate3is prepared.

Second Substrate Preparing Process

In the second substrate preparing process, the counter substrate5is prepared. In order to prepare the counter substrate5, the base substrate45, a glass substrate for example, is prepared, and a photosensitive resin material is applied onto the base substrate45by a known application method such as a spin coating method (seeFIG.8). As the photosensitive resin material, a positive-type or negative-type photoresist can be used. In the present example, as the photosensitive resin material, a positive-type photoresist is used. Next, an application film300of the photosensitive resin material is pre-baked at a predetermined temperature.

Subsequently, as illustrated inFIG.8, an exposure treatment is performed on the application film300of the photosensitive resin material. In the exposure treatment, the application film300is irradiated with light L such as ultraviolet light using a photomask400. The photomask400is configured to shield a pattern portion where the application film300is to remain and expose an unnecessary portion where the application film100is to be removed. In the exposure treatment of the present example, the region of the application film100where the second partition wall14and the second spacers17are formed is shielded from light and the other region is exposed.

In a case where a negative-type photoresist is used as the photosensitive resin material forming the application film300, in the exposure treatment, the photomask used is configured to expose a pattern portion where the application film300is to remain and to shield an unnecessary portion where the application film300is to be removed. In this case, the region of the application film300where the first partition wall12and the first spacers16are formed is exposed to light and the other region is exposed.

Subsequently, the application film300subjected to the exposure treatment is subjected to post-exposure baking to complete the photosensitive reaction of the photosensitive resin material forming the application film300. Subsequently, a development treatment is performed on the application film300in which the photosensitive reaction is completed. In the development treatment, an alkaline developing solution such as tetramethylammonium hydroxide (TMAH) or potassium hydroxide (KOH) is used to dissolve an unnecessary portion of the application film300and leave only a pattern portion of the application film300. Then, after cleaning with pure water, the substrate with the application film300partially left thereon is post-baked at a predetermined temperature to evaporate the solvent remaining on the substrate and completely cure the photoresist. In this manner, as illustrated inFIGS.9and10, the second partition wall14and the plurality of second spacers17are formed on the base substrate45.

In this manner, the counter substrate5is prepared.

Bonding Process

In the bonding process, the array substrate3and the counter substrate5are bonded together. In order to bond the array substrate3and the counter substrate5to one another, first, the dam member9and the fill member11are applied to one of the array substrate3and the counter substrate5.

In the present example, as illustrated inFIG.11, the uncured dam member9is applied in a frame shape to the outer periphery of the second partition wall14of the counter substrate5. In addition, a predetermined amount of uncured fill member11is dropped on the region of the counter substrate5surrounded by the second partition wall14using a dispenser. The viscosity of the uncured fill member11is lower than the viscosity of the uncured dam member9. As the dam member9and the fill member11, a delayed curing type of organic resin material may be used which requires a predetermined amount of time from irradiation with ultraviolet light to curing. The delayed curing type of organic resin material has a characteristic that its viscosity increases gradually after being irradiated with ultraviolet light.

Subsequently, the organic resin material forming the dam member9and the fill member11applied to the counter substrate5is irradiated with ultraviolet light. Subsequently, the array substrate3and the counter substrate5are introduced into a vacuum chamber. The interior of the vacuum chamber is evacuated to a vacuum state. Here, it is sufficient that the vacuum state is sufficient for the array substrate3and the counter substrate5to be pressurized by atmospheric pressure and the fill member11to fill uniformly between both substrates3and5when the panel body PL formed by bonding together the array substrate3and the counter substrate5is taken out from the vacuum chamber.

Then, as illustrated inFIG.12, the array substrate3and the counter substrate5are arranged in a facing positional relationship in the vacuum chamber. At this time, the first partition wall13and the second partition wall14are opposed to one another, and the first spacers16and the second spacers17are opposed to one another. Further, the array substrate3and the counter substrate5are brought relatively close to one another so that the first partition wall13and the second partition wall14abut against one another and the first spacers16and the second spacers17abut against one another. In this manner, the array substrate3and the counter substrate5are bonded to one another via the dam member9and the fill member11to form the panel body PL. The array substrate3and the counter substrate5are bonded to one another while the dam member9and the fill member11are uncured.

Next, the panel body PL is taken out from the vacuum chamber. As a result, the array substrate3and the counter substrate5are pressed together by the atmospheric pressure. Accordingly, the fill member11spreads between the array substrate3and the counter substrate5and fills the inside of the partition wall12to every corner. The gap between the array substrate3and the counter substrate5is maintained by the partition wall12and the plurality of spacers15. Thereafter, the dam member9and the fill member11are completely cured. Here, in order to completely cure the dam member9and the fill member11, the dam member9and the fill member11may be additionally irradiated with ultraviolet light, or the panel body PL may be heated. Thus, the array substrate3and the counter substrate5are bonded to one another by the sealing member7(the dam member9and the fill member11).

Additional Process

In the additional process, a protective film (not illustrated) is attached to the front and the back faces of the panel body PL. Also, in the additional process, the wiring line substrate CB is connected to the terminal region TA of the panel body PL using conductive material such as an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP). In this manner, a display control circuit such as a source driver is mounted on the panel body PL by a chip-on-film (COF) method.

Thus, the organic EL display device1is manufactured.

Advantages of First Embodiment

In the organic EL display device1according to the first embodiment, the partition wall12and the plurality of spacers15are provided in the panel body PL. The partition wall12partitions the dam member9and the fill member11. According to this configuration, when the array substrate3and the counter substrate5are bonded to one another in the manufacture of the organic EL display device1, the fill member11spreading to the outer peripheral side of the panel body PL is blocked by the partition wall12. Thus, the dam member9is prevented from being pushed out from the inside by the fill member11, and the dam member9can be suppressed from breaking. Also, the gap between the array substrate3and the counter substrate5is maintained by the partition wall12and the plurality of spacers15. Thus, the volume of the sealed space Sc filled with the fill member11is constant. Accordingly, the amount of the fill member11with respect to the sealed space Sc can be set to an appropriate amount. This can also suppress breakage of the dam member9due to the fill member11. Further, it is possible to reduce air bubble formation in the sealed space Sc. Thus, in the organic EL display device1, it is possible to suppress the impairment of the sealing properties of the organic EL element30from the dam fill structure.

In the organic EL display device1of the first embodiment, the partition wall12of the present example is formed in a closed frame shape extending around the entire periphery of the frame region FA. Thus, it is possible to prevent the fill member11from pushing out the dam member9from the inside over the entire periphery of the frame region FA. This is advantageous for preventing the dam member9from being broken.

In the organic EL display device1according to the first embodiment, the partition wall12is provided at least on the counter substrate5. The dam member9and the fill member11are applied to the counter substrate5provided with the partition wall12. Thus, irradiation of ultraviolet light for curing the dam member9and the fill member11is performed on the counter substrate5. Although there is a concern that irradiation of the array substrate3with ultraviolet light may damage the TFTs25and the organic EL elements30, according to the present example, since the counter substrate5is irradiated with ultraviolet light, it is possible to reduce damage caused by ultraviolet light to the TFTs25and the organic EL elements30in the array substrate3.

In the organic EL display device1according to the first embodiment, the first partition wall13of the array substrate3and the second partition wall14of the counter substrate5are butted against one another. The first spacers16of the array substrate3and the second spacers17of the counter substrate5are butted against one another. As described above, when the partition wall12and the spacers15are separately provided on the array substrate3and the counter substrate5, the height of the partition wall12is determined by the combination of the first partition wall13and the second partition wall14, and the height of the spacers15is determined by the combination of the first spacers16and the second spacers17. Thus, it is easy to ensure the thickness of the sealing member7as compared with the case where the partition wall12and the spacers15are provided only on the array substrate3or only on the counter substrate5. In addition, it is possible to suppress variations in the height of the partition wall12and the height of the spacers15, and to accurately manage the volume of the sealed space Sc.

In the organic EL display device1according to the first embodiment, the area of the abutting face16sof the first spacer16of the array substrate3is larger than the area of the abutting face17sof the second spacer17of the counter substrate5. As described above, when the areas of the abutting faces16sand17sof the first spacer16and the second spacer17are different from one another, even if the relative positions of the array substrate3and the counter substrate5are slightly offset when the array substrate3and the counter substrate5are bonded to one another, the second spacer17and the first spacer16can be abutted against one another. Thus, a slight positional offset is allowed between the array substrate3and the counter substrate5, and it is not necessary to have strict accuracy for the positioning of the substrates3and5.

In the organic EL display device1according to the first embodiment, the first partition wall13and the first spacers16are formed of the same material of the edge cover40and in the same layer on the array substrate3. According to this configuration, in the manufacture of the array substrate3, the first partition wall13and the first spacers16are formed together with the edge cover40in the same process. Thus, the number of processes required for manufacturing the array substrate3can be reduced as compared with a case where the first partition wall13and the first spacers16are formed in a process different from the process of forming the edge cover40.

Second Embodiment

The organic EL display device1according to the second embodiment differs from that of the first embodiment in terms of the configuration of the partition wall12. Note that in the following embodiments, the organic EL display device1is configured in a similar manner to the first embodiment described above except that the configuration of the partition wall12is different from that of the first embodiment described above. Thus, only the partition wall12having the different configuration is described, and portions with the same configuration are as in the first embodiment and will not be described in detail.

As illustrated inFIG.13, in the organic EL display device1according to the second embodiment, the partition wall12is formed in a rectangular frame-like shape extending non-linearly in a crank-like shape around the entire periphery. As illustrated inFIGS.15and16, the first partition wall13provided on the array substrate3and the second partition wall14provided on the counter substrate5are formed in the same shape as the partition wall12described above and are abutted against one another over the entire periphery.

The inner peripheral surface of the partition wall12is formed with an uneven shape. The uneven shape of the inner peripheral surface of the partition wall12includes recessed portions51and protruding portions53alternately arranged in the circumferential direction of the partition wall12. The fill member11is also filled inside the recessed portions51forming the uneven shape of the inner peripheral surface of the partition wall12. The outer peripheral surface of the partition wall12is also formed with an uneven shape. The uneven shape of the outer peripheral surface of the partition wall12includes recessed portions55and protruding portions57alternately arranged in the circumferential direction of the partition wall12. The dam member9enters the inner side of the recessed portions55forming the uneven shape of the outer peripheral surface of the partition wall12.

The partition wall12of the present example is formed in a rectangular frame-like shape. Thus, as illustrated inFIG.14, a width w of the dam member9is narrower at corner portions12cof the partition wall12. In addition, in the manufacture of the organic EL display device1, when the array substrate3and the counter substrate5are bonded to one another, the fill member11extending to the outer peripheral side of the sealed space Sc reaches the corner portions12cof the partition wall12in the final stage. Also, the space at the corner portions12cof the partition wall12is narrow. Thus, it is difficult to fill the corner portions12cwith the fill member11, and air bubbles tend to be formed.

When the width of the dam member9is narrow on the outer side of the corner portions12cof the partition wall12and air bubbles are formed in the fill member11on the inner side of the corner portions12c, the sealing properties of the organic EL element30from the dam fill structure may be impaired. However, in the present example, the recessed portions51forming the uneven shape of the inner peripheral surface of the partition wall12is provided as a portion where the fill member11reaches the final stage when the array substrate3and the counter substrate5are bonded to one another. Accordingly, even if air bubbles are formed in the fill member11, the bubbles can be located at positions away from the corner portions12cof the partition wall12.

Advantages of Second Embodiment

In the organic EL display device1of the second embodiment, the outer peripheral surface of the partition wall12is formed with an uneven shape. The dam member9also enters the inner side of the recessed portions55forming the uneven shape of the outer peripheral surface of the partition wall12. Accordingly, the contact area between the partition wall12and the dam member9is increased, and the bonding strength between the array substrate3and the counter substrate5by the dam member9can be improved.

In the organic EL display device1of the second embodiment, the inner peripheral surface of the partition wall12is formed with an uneven shape. The fill member11is also filled inside the recessed portions51forming the uneven shape of the inner peripheral surface of the partition wall12. Accordingly, the contact area between the partition wall12and the fill member11is increased, and the bonding strength between the array substrate3and the counter substrate5by the fill member11can be improved.

In addition, when air bubbles are formed in the fill member11, the recessed portions51forming the uneven shape of the inner peripheral surface of the partition wall12function as a place for the air bubbles to escape. Accordingly, the formation of air bubbles in the fill member11on the inner side of the corner portions12cof the partition wall12can be suppressed. This is advantageous in that the formation of air bubbles in the fill member11does not impair the sealing properties of the organic EL elements30from the dam fill structure and the width of the dam member9on the outer sides of the corner portions12cportions of the partition wall12can be reduced.

Third Embodiment

As illustrated inFIGS.17and18, in the organic EL display device1according to the third embodiment, the second partition wall14is formed on the counter substrate5with a reverse tapered cross section. The term “reverse tapered cross section” used herein refers to a shape in which the width of the second partition wall14on the side closer to the base substrate45is narrow and an angle α formed by the bottom face and the side faces in the width direction of the second partition wall14is 90° or greater.

The width of the bottom face of the second partition wall14is less than the width of the abutting face14sof the second partition wall14. The width of the abutting face14sof the second partition wall14is equal to the width of the abutting face13sof the first partition wall13provided on the array substrate3. The second partition wall14of the present example is formed by adjusting the exposure amount or development time so that the lower portion of the pattern portion is removed when the application film300is patterned by photolithography.

The dam member9enters a gap g1formed by a top portion of the second partition wall14on the outer peripheral side between the base substrate45. An inclined side face14aon the outer peripheral side of the second partition wall14is bonded to the dam member9. Also, the fill member11enters a gap g2formed by a top portion of the second partition wall14on the inner peripheral side between the base substrate45. An inclined side face14bon the inner peripheral side of the second partition wall14is bonded to the fill member11.

Advantages of Third Embodiment

In the organic EL display device1according to the third embodiment, the second partition wall14is formed on the counter substrate5with a reverse tapered cross section. Accordingly, the area of the contact portion between the dam member9and the base substrate45is increased due to the width of the bottom face of the second partition wall14being less than the width of the abutting face14s. Thus, the bonding strength between the array substrate3and the counter substrate5by the dam member9can be improved. In addition, in the manufacture of the organic EL display device1, when the array substrate3and the counter substrate5are bonded to one another and the fill member11extending to the outer peripheral side of the sealed space Sc reaches the second partition wall14, the fill member11enters the gap g2between the top portion of the second partition wall14and the base substrate45. Thus, the first partition wall13and the second partition wall14can be butted against one another before the fill member11runs up over the second partition wall14. If the fill member11runs up over the second partition wall14, the speed of the fill member11increases when the fill member11passes through the narrow gap between the abutting face13sof the first partition wall13and the abutting face14sof the second partition wall14before abutting, and the dam member9may be broken. The above-described configuration of the present example is advantageous in suppressing breakage of the dam member9.

Fourth Embodiment

As illustrated inFIGS.19and20, in the organic EL display device1according to the fourth embodiment, the first partition wall13is formed on the array substrate3with a reverse tapered cross section. The term “reverse tapered cross section” used herein refers to a shape in which the width of the first partition wall13on the side closer to the base substrate18is narrow and an angle β formed by the bottom face and the side faces in the width direction of the first partition wall13is 90° or greater.

The width of the bottom face of the first partition wall13is less than the width of the abutting face13sof the first partition wall13. As in the third embodiment, the second partition wall14is formed on the counter substrate5with a reverse tapered cross section. The width of the abutting face14sof the second partition wall14and the width of the abutting face13sof the first partition wall13provided on the array substrate3are the same. The first partition wall13of the present example is formed by adjusting the exposure amount or development time so that the lower portion of the pattern is removed when the application film100is patterned by photolithography.

The dam member9enters a gap g3formed by a top portion of the first partition wall13on the outer peripheral side between the base substrate18. An inclined side face13aon the outer peripheral side of the first partition wall13is bonded to the dam member9. Also, the fill member11enters a gap g4formed by a top portion of the first partition wall13on the inner peripheral side between the base substrate18. An inclined side face13bon the inner peripheral side of the first partition wall13is bonded to the fill member11. The relationship between the dam member9and the fill member11and the second partition wall14is the same as that in the third embodiment.

Advantages of Fourth Embodiment

In the organic EL display device1according to the fourth embodiment, the first partition wall13is formed on the array substrate3with a reverse tapered cross section. Accordingly, the area of the contact portion between the dam member9and the base substrate18is increased due to the width of the bottom face of the first partition wall13being less than the width of the abutting face13s. Thus, the bonding strength between the array substrate3and the counter substrate5by the dam member9can be improved. With respect to the second partition wall14, effects similar to those of the third embodiment can be obtained.

Fifth Embodiment

As illustrated inFIG.21, in the organic EL display device1according to the fifth embodiment, the partition wall12and the plurality of spacers15are provided only on the counter substrate5. The partition wall12is located at a position similar to that of the second partition wall14of the first embodiment. Each spacer15is located at a position similar to that of the second spacer17of the first embodiment. The partition wall12and each spacer15abut against the face of the array substrate3.

The partition wall12and each spacer15located at the frame region FA and each spacer15located at the display region DA have different heights on the counter substrate5. The partition wall12and each spacer15of the frame region FA are relatively high, and each spacer15of the display region DA is relatively low. The height difference between the partition wall12and each spacer15of the frame region FA and each spacer15of the display region DA corresponds to the thickness of the element layer20and is realized by using a graytone mask or a halftone mask.

In the manufacture of the organic EL display device1of the present example, as illustrated inFIG.22, the dam member9and the fill member11may be applied to the counter substrate5in the same manner as in the first embodiment. Then, the array substrate3and the counter substrate5may be bonded to one another via the dam member9and the fill member11after the dam member9and the fill member11are irradiated with ultraviolet light for starting a curing reaction. According to this configuration, it is possible to reduce damage to the TFTs25in the array substrate3and the organic EL elements30due to ultraviolet light.

Advantages of Fifth Embodiment

In the organic EL display device1according to the fifth embodiment, the partition wall12and the plurality of spacers15are provided only on the counter substrate5. According to this configuration, when the gap between the array substrate3and the counter substrate5is the same, the height of the partition wall12provided on the counter substrate5is higher than that in a case where the partition wall12and the spacers15are separately provided on the array substrate3and the counter substrate5. Thus, in the manufacture of the organic EL display device1, when the array substrate3and the counter substrate5are bonded to one another, it is possible to suppress the fill member11from running up over the partition wall12.

Sixth Embodiment

As illustrated inFIG.23, in the organic EL display device1according to the sixth embodiment, the partition wall12and the plurality of spacers15are provided only on the array substrate3. The partition wall12is located at a position similar to that of the first partition wall13of the first embodiment. Each spacer15is located at a position similar to that of the first spacer16of the first embodiment. The partition wall12and each spacer15abut against the face of the counter substrate5. The counter substrate5of the present example is formed of a plate body corresponding to the base substrate45of the first embodiment.

The partition wall12and each spacer15located at the frame region FA and each spacer15located at the display region DA have different heights. An abutting face12sof the partition wall12and an abutting face15sof each spacer15are aligned at the same height position in a planar direction orthogonal to the thickness direction of the array substrate3. The height difference between the partition wall12and each spacer15of the frame region FA and each spacer15of the display region DA corresponds to the thickness of the element layer20and is realized by using a graytone mask or a halftone mask.

In the manufacture of the organic EL display device1of the present example, as illustrated inFIG.24, the dam member9and the fill member11may be applied to the array substrate3. Then, the array substrate3and the counter substrate5may be bonded to one another via the dam member9and the fill member11after the dam member9and the fill member11are subjected to irradiation with ultraviolet light or heat treatment for starting the curing reaction.

Advantages of Sixth Embodiment

In the organic EL display device1according to the sixth embodiment, the partition wall12and the plurality of spacers15are provided only on the array substrate3. According to this configuration, when the gap between the array substrate3and the counter substrate5is the same, the height of the partition wall12provided on the array substrate3is higher than that in a case where the partition wall12and the spacers15are separately provided on the array substrate3and the counter substrate5. Thus, in the manufacture of the organic EL display device1, when the array substrate3and the counter substrate5are bonded to one another, it is possible to suppress the organic resin material forming the fill member11from running up over the partition wall12.

First Modified Example

As illustrated inFIG.25, in the organic EL display devices1according to the first to sixth embodiments, the corner portions12clocated at the four corners of the outer peripheral surface of the partition wall12may be formed as curved R faces. That is, each corner portion12cof the partition wall12may be chamfered to have a rounded curved shape. As illustrated inFIG.26, when each corner portion12cof the partition wall12of the present example is formed into an R surface, the widths w of the dam members9on the outer side the corner portions12ccan be increased. This is advantageous for enhancing the sealing properties of the organic EL element30from the dam fill structure.

Second Modified Example

As illustrated inFIG.27, in the organic EL display device1according to the first to sixth embodiments, the corner portions12cof the outer peripheral surface of the partition wall12may be formed as inclined C faces inclined with respect to the two sides of the partition wall12forming the corner portion12c. That is, each corner portion12cof the partition wall12may be chamfered to have a cut planar shape. As illustrated inFIG.28, when each corner portion12cof the partition wall12of the present example is formed into a C surface, the widths w of the dam members9on the outer side the corner portions12ccan be increased. This is advantageous for enhancing the sealing properties of the organic EL element30from the dam fill structure.

Other Embodiments

In the first embodiment, each spacer15located in the display region DA includes the first spacer16provided on the array substrate3and the second spacer17provided on the counter substrate5, but no such limitation is intended. As illustrated inFIGS.29and30, the array substrate3may be provided with seat portions50functioning as seating faces of the second spacers17instead of the first spacers16located in the display region DA. The seat portions50are integrally formed with the edge cover40at the same height as the edge cover40.

In the first embodiment described above, the first partition wall13of the array substrate3is formed of the same material as the edge cover40and in the same layer, but no such limitation is intended. The first partition wall13may include a first wall layer formed of the same material and in the same layer as an insulating film other than the edge cover40included in the element layer20and a second wall layer formed of the same material and in the same layer as the edge cover40.

In the first embodiment, although the partition wall12is formed in a closed frame-like shape, no such limitation is intended. The partition wall12may be provided only in a portion of the frame region FA. For example, the partition wall12may be provided in contact with only a portion of the dam member9which is likely to be broken in accordance with the dropping position of the fill member11or the like.

In the first embodiment, the area of the abutting face16sof the first spacer16is larger than the area of the abutting face17sof the second spacer17. However, no such limitation is intended. For example, the area of the abutting face17sof the second spacer17may be larger than the area of an abutting face16sof the first spacer16. Even with this configuration, a slight positional offset is allowed between the array substrate3and the counter substrate5, and it is not necessary to have strict accuracy for the positioning of the substrates3and5. The area of the abutting face16sof the first spacer16and the area of an abutting face17sof the second spacer17may be the same.

In the organic EL display device1of the fifth embodiment, the partition wall12may be formed with a reverse tapered cross section similar to that of the second partition wall14of the third embodiment. With this configuration, effects similar to those of the third embodiments can be obtained. Also, in the organic EL display device1of the sixth embodiment, the partition wall12may be formed with a reverse tapered cross section similar to that of the first partition wall13of the fourth embodiment. With this configuration, effects similar to those of the third embodiments can be obtained.

In the organic EL display device1according to the first to sixth embodiments, one of either the partition wall12or the plurality of spacers15may be provided on the array substrate3and the other may be provided on the counter substrate5. For example, the plurality of spacers15may be provided on the array substrate3, and the partition wall12may be provided on the counter substrate5.

As described above, the preferred embodiments are described as examples of the technique of the disclosure. However, the technique of the disclosure is not limited to the embodiments and the modified examples, and is also applicable to an embodiment in which modification, replacement, adding, omission, and the like are suitably made. It is understood by those skilled in the art that various modified examples can be made to the above embodiment without departing from the spirit of the technology of the disclosure, and such modified examples also belong to the scope of the technology of the disclosure.

For example, in the first to sixth embodiments, the organic EL layer33is provided in the individual subpixels Ps, but no limitation is intended. The organic EL layer33may be continuously provided in common in the plurality of subpixels Ps. In this case, the organic EL display device1may include a color filter, for example, to perform color tone expression of each of the subpixels Ps.

In the first to sixth embodiments, each pixel PX is constituted by the subpixels Pr, Pg, and Pb of three colors, but no such limitation is intended. The subpixels Ps constituting each of the pixels PX are not limited to having the three colors, and may have four or more colors. The subpixels Pr, Pg, and Pb of three colors constituting each pixel PX are provided adjacent to one another in the row direction Dx, but no such limitation is intended. The subpixels Ps of three colors constituting each pixel PX may be three subpixels Ps in a delta arrangement positional relationship or may be arranged in other manners.

In the first to sixth embodiments, the TFTs25provided in each subpixel Ps include the two TFTs25, the first TFT25A and the second TFT25B. However, no such limitation is intended. The number of TFTs25provided in each subpixel Ps may be three or more. In addition, the direction in which the gate lines21g, the source lines21s, and the power source lines21pextend may be switched, that is, the gate lines21gmay extend in the column direction Dy, and the source lines21sand the power source lines21pmay extend in the row direction Dx.

In first to sixth embodiments, the organic EL elements30are configured as top-emitting types, but no such limitation is intended. The organic EL elements30may be configured as bottom-emitting types in which light emitted from the organic EL layer33is extracted from the base substrate18side. The organic EL elements30may be configured as double-sided light emitting types in which light emitted from the organic EL layer33is extracted from both the base substrate18side and the counter substrate5side.

In the first to sixth embodiments, the organic EL layer33has a five-layer structure including the hole injection layer, the hole transport layer, the light-emitting layer, the electron transport layer, and the electron injection layer, but no such limitation is intended. The organic EL layer33may have a three-layer structure including a hole injection layer and hole transport layer, a light-emitting layer, and an electron transport layer and electron injection layer, and can adopt any chosen layered structure.

In the first to sixth embodiments, the organic EL display device1has been exemplified as a display device, but no such limitation is intended. The technology of the disclosure can be applied to a display device including a plurality of light-emitting elements driven by a current, for example. Examples of the display device include a display device including a quantum-dot light-emitting diode (QLED), which is a light-emitting element using a quantum dot-including layer.

INDUSTRIAL APPLICABILITY

As described above, the disclosure is useful for a display device.

REFERENCE SIGNS LIST