Method for manufacturing a display device

Abstract

A method for manufacturing a display device is disclosed. The method of one embodiment includes the following steps: providing a first functional layer composition including a first organic solvent and a first functional layer material; providing an anti-drying composition including an auxiliary solvent on the provided first functional layer composition; and drying the first organic solvent and the auxiliary solvent, wherein the specific gravity of the auxiliary solvent is less than that of the first organic solvent. This method can provide a functional layer having a uniform film thickness and a uniform surface profile across the entire display device, thereby enabling the manufacture of a display device with excellent display quality.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a display device, and more particularly to a method for manufacturing a display device including an organic layer having uniform printing characteristics. Background Art

[0002] Various display devices are being developed for use in multimedia devices such as televisions, mobile phones, tablet computers, navigation systems, and game consoles. Currently, inkjet printing and other manufacturing methods are used to manufacture the display elements included in these display devices.

[0003] Furthermore, as display devices increase in size, coating methods such as inkjet printing increase process times, leading to variations in film properties of the organic layers that make up the display element. Consequently, research is underway into display element manufacturing methods that achieve uniform element quality across the entire display device. Summary of the Invention

[0004] An object of the present invention is to provide a method for manufacturing a display device in which uniformity of film characteristics among a plurality of light-emitting elements is improved.

[0005] An object of the present invention is to provide a method for providing a display device that exhibits excellent display quality by preventing a functional layer material provided in a solution state from being unevenly dried.

[0006] One embodiment provides a method for manufacturing a display device, comprising the following steps: providing a first functional layer composition comprising a first organic solvent and a first functional layer material; providing an anti-drying composition comprising an auxiliary solvent on the provided first functional layer composition; and drying the first organic solvent and the auxiliary solvent, wherein the specific gravity of the auxiliary solvent is less than the specific gravity of the first organic solvent.

[0007] The boiling point of the auxiliary solvent may be lower than the boiling point of the first organic solvent.

[0008] The auxiliary solvent may have a specific gravity of less than 1.

[0009] The auxiliary solvent may have a boiling point below 230°C.

[0010] The auxiliary solvent may be an ethanol solvent.

[0011] The anti-drying composition may further include a surfactant.

[0012] After the step of drying the first organic solvent and the auxiliary solvent, a heat treatment step is further included. The heat treatment step can be performed at a temperature higher than the glass transition temperature of the first functional layer material.

[0013] The step of providing the first functional layer composition may include the step of providing the first functional layer composition by an inkjet printing method.

[0014] The step of providing the anti-drying composition may include the step of applying the anti-drying composition in a manner covering the provided first functional layer composition.

[0015] The material of the first functional layer may be an organic electroluminescent material or a quantum dot material.

[0016] Between the step of providing the first functional layer composition and the step of providing the anti-drying composition, a step of providing a second functional layer composition comprising a second organic solvent and a second functional layer material may be further included.

[0017] The specific gravity of the second organic solvent may be smaller than that of the first organic solvent, and the specific gravity of the auxiliary solvent may be smaller than that of the second organic solvent.

[0018] The auxiliary solvent may have a boiling point lower than a boiling point of each of the first organic solvent and the second organic solvent.

[0019] One embodiment provides a method for manufacturing a display device, comprising the following steps: printing at least one preliminary functional layer in an opening defined by a pixel defining film; providing an anti-drying layer on at least one of the preliminary functional layers; and drying at least one of the preliminary functional layers and the anti-drying layer, wherein at least one of the preliminary functional layers comprises an organic solvent and a functional layer material, the anti-drying layer comprises an auxiliary solvent, and the specific gravity of the auxiliary solvent is less than the specific gravity of the organic solvent.

[0020] The boiling point of the auxiliary solvent may be lower than the boiling point of the organic solvent.

[0021] The auxiliary solvent may include at least one of ethanol, methanol, and isopropyl alcohol.

[0022] The organic solvent may include an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, or a ketone solvent, but does not include an ethanol solvent.

[0023] The step of providing the anti-drying layer may include the step of applying the anti-drying layer in a manner covering at least one of the preliminary functional layers.

[0024] The step of providing the anti-drying layer may include the step of coating the anti-drying layer in a manner covering at least one of the preliminary functional layer and the pixel defining film.

[0025] At least one of the preliminary functional layers includes a preliminary light-emitting layer, and the material of the functional layer may be an organic electroluminescent material or a quantum dot material.

[0026] In one embodiment, the method for manufacturing a display device includes providing an anti-drying composition after providing a functional layer composition, thereby providing a display device having improved uniformity in film characteristics among a plurality of light-emitting elements located at different positions.

[0027] In one embodiment, the method for manufacturing a display device includes a step of providing an anti-drying composition, thereby preventing uneven drying of the functional layer composition before the drying step and improving the process freedom for manufacturing a large-area display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a perspective view of an electronic device in one embodiment.

[0029] Figure 2 is with Figure 1 The II' line corresponds to a cross-sectional view of a display device according to an embodiment.

[0030] Figure 3 is a plan view of a display device according to an embodiment.

[0031] Figure 4 is shown with Figure 3 Line II-II' corresponds to a cross-sectional view of a portion of a display panel according to an embodiment.

[0032] Figure 5 is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0033] Figure 6 This is a perspective view showing a step of a method for manufacturing a display device according to an embodiment.

[0034] Figure 7 This is a cross-sectional view showing a step of a method for manufacturing a display device according to an embodiment.

[0035] Figure 8a This is a cross-sectional view showing a step of a method for manufacturing a display device according to an embodiment.

[0036] Figure 8b This is a cross-sectional view showing a step of a method for manufacturing a display device according to an embodiment.

[0037] Figure 9This is a cross-sectional view showing a step of a method for manufacturing a display device according to an embodiment.

[0038] Figure 10a is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0039] Figure 10b is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0040] Figure 11 is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0041] Figure 12 This is a cross-sectional view showing a step of a method for manufacturing a display device according to an embodiment.

[0042] Figure 13 is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0043] Figure 14 is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0044] Figure 15 is a flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0045] Explanation of symbols

[0046] DD: Display device DP: Display panel

[0047] FC-1, FC-1a, FC-2a: Functional layer composition ADC: Anti-drying composition DETAILED DESCRIPTION

[0048] The present invention is susceptible to various modifications and forms, and specific embodiments are shown in the drawings and described in detail herein. However, it is not intended to limit the invention to the specific disclosed forms, and it should be understood that the invention encompasses all modifications, equivalents, and alternatives encompassed by the spirit and technical scope of the invention.

[0049] In this specification, when a certain component (or region, layer, part, etc.) is referred to as being "on" another component, "connected to" another component, or "combined with" another component, it means that it can be directly arranged / connected / combined on the other component, or a third component can be arranged between them.

[0050] In addition, in this application, the phrase "directly arranged" may mean that there is no additional layer, film, region, plate, etc. between a layer, film, region, plate, or other part. For example, the phrase "directly arranged" may mean that two layers or two parts are arranged without using an additional member such as an adhesive member between them.

[0051] The same reference numerals denote the same components. In addition, in order to effectively explain the technical content, the thickness, ratio, and size of the components are exaggerated in the drawings.

[0052] When "and / or" is mentioned, it means that all combinations of more than one possible definition of the relevant components are included.

[0053] Terms such as first and second can be used to describe a variety of components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another. For example, without departing from the scope of the present invention, the first component can be named as the second component, and similarly, the second component can be named as the first component. Singular expressions include plural expressions as long as they do not clearly indicate different meanings in the context.

[0054] Furthermore, terms such as “below,” “lower side,” “above,” and “upper side” are used to describe the relationship between components shown in the drawings. These terms are described as relative concepts based on the directions shown in the drawings.

[0055] Unless otherwise defined, all terms (including technical and scientific terms) used in this specification have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and as long as they are not interpreted as ideal or excessively formal, they should be interpreted as having the meaning explicitly defined herein.

[0056] Terms such as "including" or "having" should be understood as intending to specify the existence of the features, numbers, steps, operations, constituent elements, parts or their combinations recorded in the specification, rather than excluding in advance the existence or additional possibility of one or more other features or numbers, steps, operations, constituent elements, parts or their combinations.

[0057] Hereinafter, a method for manufacturing a display device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0058] Figure 1 It is a perspective view showing an embodiment of the electronic device ED. Figure 2 is a cross-sectional view of a display device DD according to an embodiment. Figure 2 is shown with Figure 1 The II' line corresponds to a cross-sectional view of a portion.

[0059] In one embodiment, the electronic device ED may be a large electronic device such as a television, a monitor, or an external advertising board. Alternatively, the electronic device ED may be a small or medium-sized electronic device such as a personal computer, a laptop computer, a personal digital assistant, a car navigation unit, a game console, a smartphone, a tablet computer, or a camera. Furthermore, these are merely examples; other electronic devices may also be used without departing from the scope of the present invention.

[0060] The electronic device ED may include a display device DD and a housing HAU. The display device DD may display an image IM through a display surface IS. Figure 1 , the display surface IS is parallel to a plane defined by a first direction axis DR1 and a second direction axis DR2 intersecting the first direction axis DR1. However, this is merely exemplary, and in other embodiments, the display surface IS of the display device DD may have a curved shape.

[0061] The normal direction of the display surface IS, that is, the direction of the displayed image IM in the thickness direction of the display device DD, is indicated by the third directional axis DR3. The front (or top) and back (or bottom) of each component can be distinguished by the third directional axis DR3. The directions indicated by the first, second, and third directional axes DR1, DR2, and DR3 are relative and can be changed to other directions.

[0062] The housing HAU may be configured to house the display device DD. The housing HAU may be arranged to cover the display device DD, with the upper surface, serving as the display surface IS of the display device DD, exposed. The housing HAU may cover the side and bottom surfaces of the display device DD, while also exposing the entire upper surface. However, embodiments are not limited thereto; the housing HAU may cover not only the side and bottom surfaces of the display device DD, but also a portion of the upper surface.

[0063] The display device DD may include a display panel DP and a light control layer PP arranged on the display panel DP. The display panel DP includes light emitting elements OEL-1, OEL-2, OEL-3 ( Figure 4 The display device DD may include a plurality of light emitting elements OEL-1, OEL-2, OEL-3 ( Figure 4). A light control layer PP may be disposed on the display panel DP to control the reflected light formed by external light on the display panel DP. The light control layer PP may include, for example, a polarizing layer or a color filter layer. Furthermore, unlike what is shown in the figures, in the display device DD of one embodiment, the light control layer PP may be omitted.

[0064] Figure 3 is a plan view showing a display device DD according to an embodiment. Figure 4 FIG. 4 is a cross-sectional view of a display panel DP according to an embodiment. Figure 4 is with Figure 3 The portion corresponding to the II-II' line is a cross-sectional view showing a portion of the display panel DP included in the display device DD.

[0065] The display panel DP may include a base substrate BS, a circuit layer DP-CL provided on the base substrate BS, and a display element layer DP-OEL. The display element layer DP-OEL may include: a pixel defining layer PDL; light-emitting elements OEL-1, OEL-2, and OEL-3 arranged between the pixel defining layers PDL; and an encapsulation layer TFE arranged on the light-emitting elements OEL-1, OEL-2, and OEL-3.

[0066] The base substrate BS may be a component that provides a base surface for arranging the display element layer DP-OEL. The base substrate BS may be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiment is not limited thereto, and the base substrate BS may be an inorganic layer, an organic layer, or a composite material layer.

[0067] In one embodiment, the circuit layer DP-CL is disposed on the base substrate BS and may include a plurality of transistors (not shown). The transistors (not shown) may each include a control electrode, an input electrode, and an output electrode. For example, the circuit layer DP-CL may include switching transistors and driving transistors for driving the light-emitting elements OEL-1, OEL-2, and OEL-3 of the display element layer DP-OEL.

[0068] Each light emitting element OEL-1, OEL-2, OEL-3 may include a first electrode EL1, a hole transport region HTR, light emitting layers EML-R, EML-G, EML-B, an electron transport region ETR, and a second electrode EL2. Figure 4The following embodiment is shown: the hole transport region HTR and the light emitting layers EML-R, EML-G, and EML-B of the light emitting elements OEL-1, OEL-2, and OEL-3 are arranged in the opening OH defined by the pixel definition layer PDL, and the electron transport region ETR and the second electrode EL2 are provided as a common layer in the entire light emitting elements OEL-1, OEL-2, and OEL-3. However, the embodiment is not limited to this, and Figure 4 Unlike the example shown in FIG, in one embodiment, the hole transport region HTR may not be divided by the pixel-defining layer PDL, but may cover the pixel-defining layer PDL and be provided as a common layer. In addition, in one embodiment, the electron transport region ETR may be provided by patterning inside the opening OH defined by the pixel-defining layer PDL.

[0069] For example, in one embodiment, the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, and the electron transport region ETR of the light-emitting elements OEL-1, OEL-2, and OEL-3 can be patterned and provided by an inkjet printing method. Alternatively, the light-emitting layers EML-R, EML-G, and EML-B can be patterned and provided by an inkjet printing method, and the hole transport region HTR and the electron transport region ETR can be provided as a common layer. When the hole transport region HTR and the electron transport region ETR are provided as a common layer, they can be provided using a variety of methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, and laser thermal transfer (LITI: Laser Induced Thermal Imaging).

[0070] The encapsulation layer TFE may cover the light-emitting elements OEL-1, OEL-2, and OEL-3. The encapsulation layer TFE may seal the display element layer DP-OEL. The encapsulation layer TFE may be a thin film encapsulation layer. The encapsulation layer TFE may be a single layer or a structure having multiple layers stacked thereon. The encapsulation layer TFE includes at least one insulating layer. The encapsulation layer TFE according to one embodiment of the present invention may include at least one inorganic film (hereinafter referred to as an encapsulation inorganic film). The encapsulation layer TFE according to one embodiment of the present invention may include at least one organic film (hereinafter referred to as an encapsulation organic film) and at least one encapsulation inorganic film.

[0071] The encapsulating inorganic film protects the display element layer DP-OEL from moisture and oxygen, while the encapsulating organic film protects the display element layer DP-OEL from foreign matter such as dust particles. The encapsulating inorganic film may include, but is not limited to, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The encapsulating organic film may include, but is not limited to, an acrylic organic film.

[0072] The encapsulation layer TFE is disposed on the second electrode EL2 and may be disposed to fill the opening OH.

[0073] In addition, although not shown in the drawings, in one embodiment, a capping layer (not shown) may be disposed on the second electrode EL2 , that is, a capping layer (not shown) may be disposed between the second electrode EL2 and the encapsulation layer TFE.

[0074] Reference Figure 3 and Figure 4 The display device DD may include a non-luminescent area NPXA and luminescent areas PXA-R, PXA-G, and PXA-B. Each luminescent area PXA-R, PXA-G, and PXA-B may emit light generated by each light-emitting element OEL-1, OEL-2, and OEL-3. The luminescent areas PXA-R, PXA-G, and PXA-B may be spaced apart from each other on a plane.

[0075] Each light-emitting area PXA-R, PXA-G, and PXA-B can be an area divided by a pixel-defining film PDL. The non-light-emitting area NPXA, as an area between adjacent light-emitting areas PXA-R, PXA-G, and PXA-B, can be an area corresponding to the pixel-defining film PDL. In addition, in this specification, each light-emitting area PXA-R, PXA-G, and PXA-B can correspond to a pixel (Pixel), respectively. The pixel-defining film PDL can divide the light-emitting elements OEL-1, OEL-2, and OEL-3. The light-emitting layers EML-R, EML-G, and EML-B of the light-emitting elements OEL-1, OEL-2, and OEL-3 can be arranged in the opening portion OH defined by the pixel-defining film PDL and divided. The light-emitting layers EML-R, EML-G, and EML-B divided by the pixel-defining film PDL can be formed by methods such as inkjet printing.

[0076] The pixel defining film PDL can be formed of a polymer resin. For example, the pixel defining film PDL can be formed by including a polyacrylate (Polyacrylate) resin or a polyimide (Polyimide) resin. Moreover, the pixel defining film PDL can be further formed by including an inorganic substance in addition to the polymer resin. In addition, the pixel defining film PDL can be formed by including a light absorbing substance, or by including a black pigment or a black dye. The pixel defining film PDL formed by including a black pigment or a black dye can realize a black pixel defining film. When forming the pixel defining film PDL, carbon black or the like can be used as a black pigment or a black dye, but the embodiment is not limited thereto.

[0077] Furthermore, the pixel definition layer PDL may be formed of an inorganic material. For example, the pixel definition layer PDL may include silicon nitride (SiN x ), silicon oxide (SiO x ), silicon oxynitride (SiO x N y ) etc. The pixel definition film PDL may define the light emitting regions PXA-R, PXA-G, and PXA-B. The light emitting regions PXA-R, PXA-G, and PXA-B and the non-light emitting region NPXA may be divided by the pixel definition film PDL.

[0078] The light emitting regions PXA-R, PXA-G, and PXA-B may be divided into a plurality of groups according to the colors of the lights generated from the light emitting elements OEL-1, OEL-2, and OEL-3. Figure 3 and Figure 4 In the display device DD of one embodiment shown, three light-emitting regions PXA-R, PXA-G, and PXA-B emitting red, green, and blue light are exemplarily shown. For example, the display device DD of one embodiment may include a red light-emitting region PXA-R, a green light-emitting region PXA-G, and a blue light-emitting region PXA-B that are separated from each other.

[0079] According to one embodiment, the display panel DP includes a plurality of light-emitting elements OEL-1, OEL-2, and OEL-3. Each of the light-emitting elements OEL-1, OEL-2, and OEL-3 can emit light of different wavelength bands. For example, in one embodiment, the display device DD can include a first light-emitting element OEL-1 that emits red light, a second light-emitting element OEL-2 that emits green light, and a third light-emitting element OEL-3 that emits blue light. However, embodiments are not limited thereto, and the first to third light-emitting elements OEL-1, OEL-2, and OEL-3 can emit light of the same wavelength band, or at least one of the light-emitting elements OEL-1, OEL-2, and OEL-3 can emit light of a different wavelength band.

[0080] For example, the red, green, and blue light emitting regions PXA-R, PXA-G, and PXA-B of the display device DD may correspond to the first, second, and third light emitting elements OEL-1, OEL-2, and OEL-3, respectively.

[0081] The light emitting regions PXA-R, PXA-G, and PXA-B in the display device DD according to one embodiment may be arranged in a stripe form. Figure 3The plurality of red light emitting regions PXA-R, the plurality of green light emitting regions PXA-G, and the plurality of blue light emitting regions PXA-B may be arranged along the first direction axis DR1, and may be arranged alternately in the order of the red light emitting regions PXA-R, the green light emitting regions PXA-G, and the blue light emitting regions PXA-B along the second direction axis DR2.

[0082] Although Figure 3 While the light-emitting regions PXA-R, PXA-G, and PXA-B all have similar areas, the present invention is not limited thereto. The areas of the light-emitting regions PXA-R, PXA-G, and PXA-B may differ from one another depending on the wavelength band of the emitted light. Furthermore, the areas of the light-emitting regions PXA-R, PXA-G, and PXA-B may represent areas when viewed from a plane defined by the first and second direction axes DR1 and DR2.

[0083] In addition, the arrangement of the light emitting regions PXA-R, PXA-G, and PXA-B is not limited to Figure 3 As shown in FIG, the order in which the red light-emitting regions PXA-R, the green light-emitting regions PXA-G, and the blue light-emitting regions PXA-B are arranged can be provided in various combinations according to the display quality characteristics required by the display device DD. For example, the light-emitting regions PXA-R, PXA-G, and PXA-B can be arranged in a pentile arrangement or a diamond arrangement.

[0084] Furthermore, the areas of the light emitting regions PXA-R, PXA-G, and PXA-B may be different from each other. For example, in one embodiment, although the area of the green light emitting region PXA-G may be smaller than the area of the blue light emitting region PXA-B, the embodiment is not limited thereto.

[0085] Figure 5 is a flow chart showing a method for manufacturing a display device according to an embodiment. The method for manufacturing a display device according to an embodiment may include manufacturing Figures 2 to 4 The steps of the light-emitting elements OEL-1, OEL-2, and OEL-3 described in . Figure 6 This is a perspective view showing a step in a method for manufacturing a display device according to an embodiment. Figure 7 This is a cross-sectional view illustrating a step in a method for manufacturing a display device according to an embodiment. Figure 7 is shown with Figure 6 The III-III' line corresponds to the portion of the diagram. Figure 8a and Figure 8b Each of them is a cross-sectional view showing a part of the steps of the manufacturing method according to one embodiment.

[0086] The display device manufacturing method 10 of one embodiment may include the following steps: providing a first functional layer composition (S10); providing an anti-drying composition (S20); and drying the organic solvent and the auxiliary solvent (S50). Furthermore, the display device manufacturing method 10 of one embodiment may further include a step of performing a heat treatment (S70) after drying the organic solvent and the auxiliary solvent (S50).

[0087] The first functional layer composition FC-1 may include a first organic solvent SV-1 and a first functional layer material FM-1. The first functional layer composition FC-1 may be used for Figure 4 The light-emitting elements OEL-1, OEL-2, and OEL-3 described in the foregoing are compositions for forming the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, or the electron transport region ETR. That is, in the light-emitting elements OEL-1, OEL-2, and OEL-3, the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, or the electron transport region ETR may be the first functional layer, and the first functional layer composition FC-1 may be a liquid composition for forming the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, or the electron transport region ETR.

[0088] Figures 6 to 8b The method of forming the light-emitting layers EML-R, EML-G, and EML-B as the first functional layer is exemplarily shown and described in FIG. However, the embodiment is not limited thereto. In addition to changing the functional layer material, referring to FIG. Figures 6 to 8b The contents described above can also be applied similarly to the steps of manufacturing each functional layer.

[0089] The first functional layer composition FC-1 used to form the light-emitting layers EML-R, EML-G, and EML-B as the first functional layer may include an organic light-emitting material or a quantum dot material as the first functional layer material FM-1. However, embodiments are not limited thereto. When the first functional layer is a hole transport region HTR or an electron transport region ETR, the first functional layer material may include a hole transport material or an electron transport material, respectively.

[0090] The first organic solvent SV-1 may include at least one of an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, and a ketone solvent. For example, the first organic solvent SV-1 may include at least one of benzene, toluene, xylene, and methyl ethyl ketone. However, the embodiment is not limited thereto, and a mixture of multiple organic solvents may be used, taking into account the solubility of the functional layer material used.

[0091] Figure 6 、 Figure 7 、 Figure 8a as well as Figure 8b exemplarily shows a method of providing a red light emitting layer EML-R among the light emitting layers EML-R, EML-G, and EML-B as a first functional layer. However, the embodiment is not limited thereto. Figures 5 to 8b The manufacturing method of the display device according to the embodiment described above can also be applied to a method of providing a hole transport region HTR, an electron transport region ETR, and light emitting layers EML-G and EML-B that emit light of other colors.

[0092] Figure 6 and Figure 7 Schematically shows the steps of providing the first functional layer composition FC-1 and the anti-drying composition ADC by inkjet printing. Figure 6 and Figure 7 The first inkjet head IZ-H1 and the second inkjet head IZ-H2 can respectively provide the first functional layer composition FC-1 and the anti-drying composition ADC through the nozzles NZ-1 and NZ-2 while moving along the working direction MD parallel to the direction of the first direction axis DR1.

[0093] Figure 6 and Figure 7 FIG. 4 exemplarily shows a part of the manufacturing steps of the light emitting element OEL-1 included in the display panel DP of one embodiment. Figure 6 and Figure 7 , there is shown a step of providing the first functional layer composition FC-1 and the anti-drying composition ADC to the red light-emitting region PXA-R among the light-emitting regions PXA-R, PXA-G, and PXA-B.

[0094] The first inkjet head IZ-H1 first provides the first functional layer composition FC-1 while moving along the working direction MD, and the second inkjet head IZ-H2 provides the anti-drying composition ADC on top of the provided first functional layer composition while moving along the working direction MD. The anti-drying composition ADC can be provided in a manner that covers the provided first functional layer composition FC-1. Figure 6 When the first inkjet head IZ-H1 and the second inkjet head IZ-H2 move along the working direction MD, the first sub-light-emitting area PXA-R1 is in a state of being provided with both the first functional layer composition FC-1 and the anti-drying composition ADC, the second sub-light-emitting area PXA-R2 is equivalent to a state of being provided with the anti-drying composition ADC after being provided with the first functional layer composition FC-1, and the third sub-light-emitting area PXA-R3 is equivalent to a state of being provided with the first functional layer composition FC-1.

[0095] The anti-drying composition ADC includes an auxiliary solvent, and the specific gravity of the auxiliary solvent can be lower than the specific gravity of the first organic solvent SV-1 contained in the first functional layer composition FC-1. For example, the specific gravity of the auxiliary solvent can be lower than 1. Therefore, the anti-drying composition ADC can be provided on top of the provided first functional layer composition FC-1 without being mixed with the first functional layer composition FC-1.

[0096] Furthermore, the boiling point of the auxiliary solvent may be lower than the boiling point of the first organic solvent SV-1. For example, the boiling point of the auxiliary solvent may be lower than 230°C.

[0097] The auxiliary solvent may be an ethanol-based solvent. For example, the auxiliary solvent may include at least one of ethanol, methanol, and isopropanol, but the embodiment is not limited thereto. The auxiliary solvent has a boiling point lower than that of the first organic solvent SV-1 and may be used without limitation as long as it does not mix or chemically react with the first functional layer composition FC-1.

[0098] The anti-drying composition ADC may further comprise a surfactant. The surfactant may be a fluorine-based, amine-based, ether-based, alcohol-based, ester-based, or thiol-based compound. For example, the surfactant may comprise FC-4430 (3M TM ), At least one of (3-aminopropyl)trimethoxysilane, (3-aminopropyl)triethoxysilane, N-(2-aminoethyl)-3-aminpropyltrimethoxysilane, (3-glycidyloxypropyl)trimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, (1-hydroxyallyl)-trimethylsilane, acetoxyethyltriethoxysilane, and (3-mercaptopropyl)trimethoxysilane. However, the embodiment is not limited thereto, and any substance can be used without limitation as long as it is used to improve the printability of the functional layer composition provided after providing the anti-drying composition ADC.

[0099] After the step of drying the organic solvent and the auxiliary solvent (S50), the surfactant may still be contained in the functional layer of the manufactured light-emitting element. The surfactant may be contained in the interface between adjacent functional layers or in at least one functional layer. For example, Figure 8a and Figure 8b , exemplified in Figure 1 , when a surfactant is included in the anti-drying composition ADC provided on top of the first functional layer composition FC-1 for forming the light-emitting layer, the surfactant can be primarily included on the upper surface of the light-emitting layer EML-R adjacent to the electron transport region ETR. Furthermore, the surfactant can be included so as to be distributed at the interface between the light-emitting layer EML-R and the electron transport region ETR, or so as to be included adjacent to the lower surface of the electron transport region ETR adjacent to the light-emitting layer EML-R.

[0100] The anti-drying composition ADC may be a substance having the following function: preventing the provided first functional layer composition FC-1 from being dried at normal temperature / normal pressure until the drying step (S50) for drying the first organic solvent SV-1 included in the first functional layer composition FC-1 is performed.

[0101] The display device manufacturing method 10 of one embodiment includes a step (S30) of providing an anti-drying composition. By providing an anti-drying composition ADC on top of the first functional layer composition FC-1 provided by a printing method, the anti-drying composition ADC covers the first functional layer composition FC-1, thereby preventing uneven drying of the first functional layer composition FC-1 provided to multiple light-emitting elements before the drying step (S50). Specifically, the display device manufacturing method 10 of one embodiment includes the step (S30) of providing an anti-drying composition. The anti-drying layer ADL prevents drying of the first functional layer composition FC-1, which is preferentially printed, while the first functional layer composition FC-1 is being provided to the entire display device DD. Consequently, the anti-drying layer ADL, which serves as a printed layer of the anti-drying composition ADC, maintains a uniform thickness of the first functional layer composition FC-1 provided to the entire display device DD and the preliminary functional layer P-EML formed therefrom.

[0102] Each functional layer manufactured using the display device manufacturing method 10 according to one embodiment can exhibit uniform film properties across the multiple light-emitting elements included in the display device. For example, the thickness variation of the light-emitting layer EML-R in the multiple first light-emitting elements OEL-1 can be less than 10%. That is, for the multiple light-emitting layers EML-R manufactured using the display device manufacturing method 10 according to one embodiment, the thickness difference between the thickest and thinnest light-emitting layers EML-R in the entire display device DD can be less than 10% of the average thickness. Furthermore, the luminance variation of light emitted from the multiple first light-emitting elements OEL-1 can also be less than 10%. That is, among the multiple first light-emitting elements OEL-1 including the multiple light-emitting layers EML-R manufactured using the display device manufacturing method 10 according to one embodiment, the luminance difference between the light-emitting element OEL-1 exhibiting the highest luminance and the light-emitting element OEL-1 exhibiting the lowest luminance can be less than 10% of the average luminance of the light-emitting elements OEL-1.

[0103] Figure 8a is a diagram showing a step (S10) of providing a first functional layer composition FC-1 including a first organic solvent SV-1 and a first functional layer material FM-1, Figure 8b 1 is a diagram showing a step ( S30 ) of providing an anti-drying composition ADC including an auxiliary solvent on the provided first functional layer composition FC-1. Figure 8b The state of the preparation display panel P-DP before the step ( S50 ) of performing drying is exemplarily shown.

[0104] The first functional layer composition FC-1 including the first organic solvent SV-1 and the first functional layer material FM-1 can be provided into the opening portion OH defined by the pixel defining film PDL. The first functional layer composition FC-1 can be provided onto the hole transport region HTR. Although the situation in which the hole transport region HTR is provided into the opening portion OH is shown, the embodiment is not limited thereto. The hole transport region HTR arranged in the opening portion OH can be provided by an inkjet printing method. Moreover, in the case where the hole transport region HTR covers the pixel defining film PDL and is provided as a common layer, the hole transport region HTR can be provided by various methods such as vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, laser thermal transfer (LITI: Laser Induced Thermal Imaging), and the like.

[0105] Reference Figure 8b The anti-drying composition ADC may be provided in the opening OH defined by the pixel defining layer PDL. The anti-drying composition ADC may be provided by an inkjet printing method, but the embodiment is not limited thereto.

[0106] The step of drying the organic solvent and the auxiliary solvent (S50) may be a step of vacuum drying the organic solvent and the auxiliary solvent. In the step of drying the organic solvent and the auxiliary solvent (S50), the first organic solvent SV-1 of the first functional layer composition and the auxiliary solvent of the anti-drying composition ADC may be evaporated and removed. The step of drying the organic solvent and the auxiliary solvent (S50) may be performed in a vacuum chamber.

[0107] After the step (S50) of drying the organic solvent and the auxiliary solvent, a heat treatment step (S70) may be performed. The heat treatment step (S70) may further remove the organic solvent not removed in the drying step (S50). Furthermore, in the heat treatment step (S70), the functional layer materials may be rearranged to ultimately form a functional layer.

[0108] The heat treatment step (S70) may be performed at a temperature above the glass transition temperature of the functional layer material. For example, the heat treatment step (S70) may be performed at a temperature range of 140° C. to 160° C. However, the embodiment is not limited thereto, and the temperature range may be adjusted depending on the compound used as the functional layer material.

[0109] Figure 9 This is a cross-sectional view showing a portion of the steps of a method for manufacturing a display device according to an embodiment. Figure 9 is shown with Figure 8b The diagram corresponds to a state of the prepared display panel P-DP-a proceeding to the step ( S30 ) of providing an anti-drying composition including an auxiliary solvent on the first functional layer composition. Figure 9 The situation and Figure 8b The illustrated embodiment is different in that the anti-drying composition ADC is fully provided in a manner of covering not only the upper portion of the printed first functional layer composition FC-1 but also the pixel defining layer PDL. Figure 9 The anti-drying composition ADC provided in the present invention can be provided in various coating forms. Figure 9 The anti-drying composition ADC provided in the present invention can be provided by inkjet printing, slit coating, spray coating, spin coating, roller coating, etc., and the embodiment is not limited thereto.

[0110] Figures 10a to 15 is a flow chart showing a method for manufacturing a display device according to an embodiment. Figures 10a to 15 When describing the method for manufacturing a display device according to an embodiment, the method will not be described in detail. Figures 1 to 9 For content that is repeated in the descriptions above, the differences will be mainly explained.

[0111] Figure 10a and Figure 10b is a flowchart illustrating a method for manufacturing a display device according to an embodiment. Figure 10a and Figure 10b The manufacturing method 10-1 of a display device according to an embodiment may be a manufacturing method of a display device including a plurality of functional layers. The plurality of functional layers may be respectively formed by referring to Figures 5 to 9 A method for manufacturing a functional layer is provided. A method for manufacturing a display device according to an embodiment 10 - 1 may include the following steps: forming a first preliminary functional layer ( S110 ); and forming a second preliminary functional layer ( S130 ).

[0112] In this specification, the first preliminary functional layer and the second preliminary functional layer respectively refer to the first functional layer and the second functional layer before heat treatment. For example, in the display device manufactured by the display device manufacturing method 10-1 of an embodiment, the first functional layer may be the hole transport region HTR ( Figure 4 ), the second functional layer can be a light-emitting layer EML-R, EML-G, EML-B ( Figure 4 ). In addition, in one embodiment, the first functional layer may be a light-emitting layer EML-R, EMLG, EML-B ( Figure 4 ), the second functional layer can be an electron transport region ETR ( Figure 4 ). However, the embodiment is not limited thereto, and when manufacturing a plurality of functional layers provided by sequential stacking, it is possible to use Figure 10a and Figure 10b A method 10-1 for manufacturing a display device according to an embodiment is shown.

[0113] In the display device manufacturing method 10-1 according to one embodiment, the first preparation functional layer step (S110) may include the following steps: providing a first functional layer composition (S10); providing a first anti-drying composition (S30); drying the first organic solvent and the first auxiliary solvent (S50). The first functional layer composition may include a first organic solvent and a first functional layer material, and the first anti-drying composition may include a first auxiliary solvent. The specific gravity of the first auxiliary solvent may be less than the specific gravity of the first organic solvent, and the first auxiliary solvent may have a boiling point below the boiling point of the first organic solvent. The step of drying the first organic solvent and the first auxiliary solvent (S50) may include a step of vacuum drying the first organic solvent and the first auxiliary solvent. The first preparation functional layer may be formed by vacuum drying the first organic solvent and the first auxiliary solvent.

[0114] The step of forming the second preliminary functional layer (S130) can be performed in sequence after the first preliminary functional layer is formed. The second preliminary functional layer forming step (S130) may include the following steps: providing a second functional layer composition (S10-1); providing a second anti-drying composition (S30-1); and drying the second organic solvent and the second auxiliary solvent (S50-1). The second functional layer composition may include a second organic solvent and a second functional layer material, and the second anti-drying composition may include a second auxiliary solvent. The specific gravity of the second auxiliary solvent may be less than the specific gravity of the second organic solvent, and may have a boiling point below the boiling point of the second organic solvent. The second auxiliary solvent may be the same as the first auxiliary solvent or different from each other. The first auxiliary solvent and the second auxiliary solvent may be ethanol-based organic solvents. For the first auxiliary solvent and the second auxiliary solvent, the same method as in reference to Figures 5 to 9 The contents are the same as those described in the display device manufacturing method of the embodiment described above.

[0115] The step of drying the second organic solvent and the second auxiliary solvent ( S50 - 1 ) may include vacuum drying the second organic solvent and the second auxiliary solvent. The second preliminary functional layer may be formed by vacuum drying the second organic solvent and the second auxiliary solvent.

[0116] After the first preliminary functional layer and the second preliminary functional layer are sequentially formed, a heat treatment step (S70) may be performed. Figure 10a and Figure 10b The display device manufacturing method 10-1 of an embodiment shown shows a situation in which the heat treatment step (S70) is performed after the second preliminary functional layer forming step (S130), but the embodiment is not limited to this. The heat treatment step (S70) can also be added after the step (S110) of forming the first preliminary functional layer.

[0117] Figure 11 is a flowchart illustrating a method for manufacturing a display device according to an embodiment. Figure 12 It shows Figure 11 A diagram illustrating a step of a method for manufacturing a display device according to an embodiment is shown.

[0118] Reference Figure 11 According to an embodiment of the present invention, the display device manufacturing method 10-2 may include the following steps: providing a first functional layer composition (S10); providing a second functional layer composition (S10-1); providing an anti-drying composition (S30); and drying the organic solvent and the auxiliary solvent (S50-2). Figure 5 A display device manufacturing method 10 according to an embodiment of the present invention is described. Figure 11The display device manufacturing method 10-2 of the embodiment shown in the figure further includes a second functional layer composition providing step (S10-1) between the first functional layer composition providing step (S10) and the anti-drying composition providing step (S30), which is different in this respect. Figure 11 The display device manufacturing method 10-2 of the embodiment shown in FIG1 is to perform the second functional layer composition providing step (S10-1) after the first functional layer composition providing step (S10), and then perform the anti-drying composition providing step (S30), which is the same as the reference Figure 10a and Figure 10b In the display device manufacturing method 10-1 of the described embodiment, there is a difference in that a first anti-drying composition providing step (S30) and a step of drying the first organic solvent and the first auxiliary solvent (S50) are added between the first functional layer composition providing step (S10) and the second functional layer composition providing step (S10-1).

[0119] That is, refer to Figure 11 The display device manufacturing method 10-2 of the illustrated embodiment is a method for forming a plurality of continuously stacked functional layers, which may include a first functional layer composition providing step (S10); a second functional layer composition providing step (S10-1); and an anti-drying composition providing step (S30) performed in sequence.

[0120] Figure 12 Shown Figure 11 The flowchart shown shows the state of the anti-drying composition providing step (S30). A first functional layer composition FC-1a is provided on the first electrode EL1 within the opening OH defined by the pixel definition layer PDL. A second functional layer composition FC-2a is provided on the provided first functional layer composition FC-1a, and an anti-drying composition ADC is provided on the second functional layer composition FC-2a. The portion printed with the first functional layer composition FC-1a is the first preliminary functional layer P-HTR, the portion printed with the second functional layer composition FC-2a is the second preliminary functional layer P-EML, and the portion printed with the anti-drying composition ADC corresponds to the anti-drying layer ADL.

[0121] exist Figure 12 In one embodiment shown, the first functional layer composition FC-1a may include a composition for forming a hole transport region HTR ( Figure 4 That is, the first functional layer composition FC-1a may include a first organic solvent SV-1a and a first functional layer material FM-1a, and the first functional layer material FM-1a may include a well-known hole injection material or a well-known hole transport material.

[0122] Furthermore, the second functional layer composition FC-2a may include the components for forming the light-emitting layers EML-R, EML-G, and EML-B ( Figure 4 ) functional layer material. That is, the second functional layer composition FC-2a may include a second organic solvent SV-2a and a second functional layer material FM-2a, and the second functional layer material FM-2a may include a known luminescent material. For example, the second functional layer material FM-2a may include a fluorescent luminescent material, a phosphorescent luminescent material, or quantum dots.

[0123] The second functional layer composition FC-2a may be provided with an anti-drying composition ADC. The anti-drying composition ADC may be provided in a manner that covers the printed second functional layer composition FC-2a. Figure 12 The embodiment of the present invention covers the upper portion of the second functional layer composition FC-2a printed with the anti-drying composition ADC and is applied to the opening portion OH defined by the pixel-defining layer PDL, but the embodiment is not limited thereto. The anti-drying composition ADC can be provided to cover not only the upper portion of the printed second functional layer composition FC-2a but also the pixel-defining layer PDL.

[0124] exist Figure 11 and Figure 12 In the display device manufacturing method 10-2 according to one embodiment, the specific gravity of the second organic solvent SV-2a can be smaller than that of the first organic solvent SV-1a. Therefore, the second functional layer composition FC-2a can cover and maintain the first functional layer composition FC-1a disposed thereunder without mixing with the first functional layer composition FC-1a.

[0125] The first functional layer composition FC-1a and the second functional layer composition FC-2a can be applied sequentially via inkjet printing. The second functional layer composition FC-2a is applied so as to cover the printed first functional layer composition FC-1a. This prevents the printed first functional layer composition FC-1a from drying out. Specifically, by continuously applying the second functional layer composition FC-2a after the first functional layer composition FC-1a is applied until the entire first functional layer composition FC-1a is printed across the entire display panel, the first organic solvent SV-1a in the previously printed first functional layer composition FC-1a is prevented from drying out preferentially. This ensures uniform printing quality across the entire display panel, including the applied thickness of the first functional layer composition FC-1a and the outline of the printed area.

[0126] The anti-drying composition ADC is applied to the second functional layer composition FC-2a to prevent drying of the first functional layer composition FC-1a and the second functional layer composition FC-2a. The specific gravity of the auxiliary solvent included in the anti-drying composition ADC can be less than that of the second organic solvent SV-2a. Furthermore, the boiling point of the auxiliary solvent can be lower than that of the first organic solvent SV-1a and the second organic solvent SV-2a.

[0127] After the step of providing the anti-drying composition (S30), a step of drying the organic solvent and the auxiliary solvent (S50-2) may be performed. In the step of drying the organic solvent and the auxiliary solvent (S50-2), the first organic solvent SV-1a, the second organic solvent SV-2a, and the auxiliary solvent may be removed. The step of drying the organic solvent and the auxiliary solvent (S50-2) may be performed in a vacuum chamber.

[0128] After the step of drying the organic solvent and the auxiliary solvent (S50-2), a heat treatment step (S70) may be performed. The first functional layer and the second functional layer may be formed by the heat treatment step (S70). For example, Figure 12 The first functional layer formed by the method for manufacturing a display device according to an embodiment of the present invention may be a hole transport region HTR ( Figure 4 ), the second functional layer can be a light-emitting layer EML-R, EML-G, EML-B ( Figure 4 ).

[0129] After forming the first and second functional layers, a step of forming a third functional layer disposed on the second functional layer may be performed. For example, the third functional layer may be formed using the above-mentioned Figures 5 to 9 The present invention provides a method for forming a third functional layer by using the functional layer manufacturing method described in

[15] ,

[16] ,

[17] ,

[18] ,

[19] ,

[20] ,

[21] ,

[22] ,

[23] ,

[24] ,

[25] ,

[26] ,

[27] ,

[28] ,

[29] ,

[30] ,

[31] ,

[32] ,

[33] ,

[34] ,

[35] ,

[36] ,

[37] ,

[38] ,

[39] ,

[40] ,

[41] ,

[42] ,

[43] ,

[44] ,

[45] ,

[46] ,

[47] ,

[48] ,

[49] ,

[50] ,

[51] ,

[52] ,

[53] ,

[54] ,

[55] ,

[56] ,

[57] ,

[58] ,

[59] ,

[60] ,

[61] ,

[62] ,

[63] ,

[64] ,

[65] ,

[66] ,

[67] ,

[68] ,

[69] ,

[70] ,

[71] ,

[72] ,

[73] ,

[74] ,

[75] ,

[76] ,

[77] ,

[78] ,

[79] ,

[80] ,

[81] ,

[82] ,

[83] ,

[84] ,

[85] ,

[86] ,

[87] ,

[88] ,

[89] ,

[90] ,

[91] ,

[92] ,

[93] ,

[94] ,

[95] ,

[96] ,

[97] ,

[98] ,

[99] ,

[100]

[0130] However, the embodiment is not limited thereto, and the display device manufacturing method 10-2 of one embodiment may further include at least one functional layer composition providing step between the second functional layer composition providing step (S10-1) and the anti-drying composition providing step (S30). For example, one embodiment may further include a third functional layer composition providing step. In one embodiment, the third functional layer composition may include a composition for forming an electron transport region ETR ( Figure 4That is, the third functional layer composition may include a third organic solvent and a third functional layer material, and the third functional layer material may include a well-known electron injection material or a well-known electron transport material.

[0131] Figures 13 to 15 It shows the manufacturing Figure 3 and Figure 4 Flowchart of a method for manufacturing a display device according to an embodiment of a display device described in .

[0132] Reference Figure 3 and Figure 4 In one embodiment, a display device DD includes a display panel DP including a plurality of light-emitting elements. Each of the plurality of light-emitting elements included in the display panel DP may include a first electrode EL1, a second electrode EL2 facing the first electrode EL1, and a plurality of functional layers arranged between the first electrode EL1 and the second electrode EL2. The plurality of functional layers may include a hole transport region HTR, light-emitting layers EML-R, EML-G, EML-B, and an electron transport region ETR. In addition, although FIG4 shows a case where the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, and the electron transport region ETR are each a single layer, the embodiment is not limited thereto, and the hole transport region HTR, the light-emitting layers EML-R, EML-G, EML-B, and the electron transport region ETR may each include a plurality of sub-functional layers. For example, the hole transport region HTR may include a hole injection layer, a hole transport layer, an electron blocking layer, and the like, and the electron transport region ETR may include an electron injection layer, an electron transport layer, a hole blocking layer, and the like. The light emitting layers EML-R, EML-G, and EML-B may include a plurality of stacked sub-light emitting layers.

[0133] Reference Figure 13 According to an embodiment, a method for manufacturing a display device may include the following steps: forming a hole transport region (S100); forming a light-emitting layer (S300); and forming an electron transport region (S500). That is, the method for manufacturing a display device according to an embodiment may include the steps of forming at least one functional layer, including a hole transport region HTR, light-emitting layers EML-R, EML-G, and EML-B, and an electron transport region ETR, on the first electrode EL1. According to an embodiment, a method for manufacturing a display device may include the steps of forming a hole transport region HTR on the first electrode EL1; forming light-emitting layers EML-R, EML-G, and EML-B, respectively, on the hole transport region HTR; and forming an electron transport region ETR on the light-emitting layers EML-R, EML-G, and EML-B.

[0134] The hole transport region HTR, the light emitting layers EML-R, EML-G, EML-B and the electron transport region ETR corresponding to the functional layer can be used Figure 14 A method for manufacturing a display device according to an embodiment is provided.

[0135] A display device manufacturing method 10-a according to one embodiment may include the following steps: printing a preliminary functional layer (S10-a); providing an anti-drying layer (S30-a); and drying the preliminary functional layer and the anti-drying layer (S50-a). Furthermore, the display device manufacturing method 10-a according to one embodiment may further include a heat treatment step (S70-a) after drying the preliminary functional layer and the anti-drying layer (S50-a).

[0136] The preliminary functional layer printing step (S10-a) is equivalent to the step of printing at least one preliminary functional layer in the opening OH defined by the pixel definition layer PDL. The preliminary functional layer printing step (S10-a) may include the following steps: Figure 5 The step of providing the first functional layer composition (S10) described in the preceding text is equivalent to providing the anti-drying layer on at least one preparatory functional layer to be printed. The step of providing the anti-drying layer (S30-a) may include: Figure 5 The step of providing the anti-drying composition (S30) described in the above. Furthermore, the step of drying the preliminary functional layer and the anti-drying layer (S50-a) is equivalent to the step of drying at least one preliminary functional layer and the preliminary anti-drying layer. The step of drying the preliminary functional layer and the anti-drying layer (S50-a) may include Figure 5 The step (S50) of drying the organic solvent and the auxiliary solvent is described in detail.

[0137] Reference Figure 3 and Figure 4 The display device DD according to an embodiment of the present invention includes a plurality of light emitting areas. In the display device DD including the plurality of light emitting areas, the display device DD may be configured as follows: Figure 15 The manufacturing steps shown in FIG. 1 are followed by a light emitting layer forming step ( S300 ).

[0138] The light-emitting layer forming step (S300) can be performed by repeatedly performing the light-emitting composition providing step and the anti-drying composition providing step. The light-emitting layer forming step (S300) can include sequentially performing the steps of providing a first color light-emitting composition (S310), providing a first anti-drying composition (S320), providing a second color light-emitting composition (S330), providing a second anti-drying composition (S340), providing a third color light-emitting composition (S350), providing a third anti-drying composition (S360), and drying the organic solvent and auxiliary solvent (S370). Furthermore, the light-emitting layer forming step (S300) can include a heat treatment step (S380) after the step of drying the organic solvent and auxiliary solvent (S370).

[0139] In the step of drying the organic solvent and the auxiliary solvent (S370), the organic solvents included in the first to third color luminescent compositions and the auxiliary solvents included in the first to third anti-drying compositions can be vacuum dried. Furthermore, in the heat treatment step (S380), any residual organic solvent and auxiliary solvent not removed in the step of drying the organic solvent and the auxiliary solvent (S370) are completely removed, and the luminescent material can be rearranged to form a luminescent layer.

[0140] The first color luminescent composition may include an organic solvent and a first color luminescent material, the second color luminescent composition may include an organic solvent and a second color luminescent material, and the third color luminescent composition may include an organic solvent and a third color luminescent material. The first to third colors may be colors of different wavelengths. For example, the first color may be red, the second color may be green, and the third color may be blue, but the embodiment is not limited thereto.

[0141] For example, in the method for manufacturing a display device according to an embodiment, the light emitting layer forming step (S300) includes a step of providing an anti-drying composition after providing respective light emitting compositions of different colors, thereby preventing the drying of the preliminary light emitting layer P-EML ( Figure 7 ) is formed before the entire display panel is formed, the pre-printed light emitting layer P-EML ( Figure 7 ) is dried first. Therefore, the display device manufacturing method according to one embodiment can improve the formation of the preliminary light-emitting layer P-EML ( Figure 7 ) time difference causes the problem of reduced film uniformity.

[0142] In a display device manufacturing method according to one embodiment, in order to maintain uniform printing quality from the time the functional layer composition provided in a liquid state using an organic solvent is printed until the drying step is performed, a drying-preventing composition providing step may be included after the functional layer composition providing step. Consequently, a display device according to one embodiment manufactured using the display device manufacturing method according to one embodiment can improve the film uniformity of the functional layer constituting the light-emitting element, thereby exhibiting excellent display quality.

[0143] Although the above description is made with reference to the preferred embodiments of the present invention, any person skilled in the art or a person with ordinary knowledge in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the idea and technical field of the present invention as described in the claims.

[0144] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be determined by the scope described in the claims.

Claims

1. A method for manufacturing a display device, comprising the following steps: moving a first inkjet head in a first direction while providing a first functional layer composition including a first organic solvent and a first functional layer material; moving the second inkjet head along the first direction while coating the first functional layer composition so as to cover the first functional layer composition to provide an anti-drying composition including an auxiliary solvent; and drying the first organic solvent and the auxiliary solvent, in, The specific gravity of the auxiliary solvent is smaller than that of the first organic solvent, The boiling point of the auxiliary solvent is lower than the boiling point of the first organic solvent.

2. The method for manufacturing a display device according to claim 1, wherein: The specific gravity of the auxiliary solvent is less than 1.

3. The method for manufacturing a display device according to claim 1, wherein: The auxiliary solvent has a boiling point below 230°C.

4. The method for manufacturing a display device according to claim 1, wherein: The auxiliary solvent is an ethanol solvent.

5. The method for manufacturing a display device according to claim 1, wherein: The anti-drying composition further comprises a surfactant.

6. The method for manufacturing a display device according to claim 1, wherein: After the step of drying the first organic solvent and the auxiliary solvent, a heat treatment step is further included. The heat treatment step is performed at a temperature above the glass transition temperature of the material of the first functional layer.

7. The method for manufacturing a display device according to claim 1, wherein: The material of the first functional layer is an organic electroluminescent material or a quantum dot material.

8. The method for manufacturing a display device according to claim 1, wherein: Between the step of providing the first functional layer composition and the step of providing the anti-drying composition, the step of providing a second functional layer composition comprising a second organic solvent and a second functional layer material is further included.

9. The method for manufacturing a display device according to claim 8, wherein: The specific gravity of the second organic solvent is smaller than that of the first organic solvent. The specific gravity of the auxiliary solvent is smaller than that of the second organic solvent.

10. The method for manufacturing a display device according to claim 8, wherein: The auxiliary solvent has a boiling point lower than a boiling point of each of the first organic solvent and the second organic solvent.

11. A method for manufacturing a display device, comprising the following steps: Moving the first inkjet head along a first direction, while printing at least one preliminary functional layer toward the opening defined by the pixel defining film; moving a second inkjet head along the first direction while coating at least one of the preliminary functional layers in a manner covering the preliminary functional layer to provide an anti-drying layer; and drying at least one of the preliminary functional layer and the anti-drying layer, in, At least one of the preliminary functional layers comprises an organic solvent and a functional layer material, The anti-drying layer includes an auxiliary solvent, The specific gravity of the auxiliary solvent is less than that of the organic solvent, The boiling point of the auxiliary solvent is lower than the boiling point of the organic solvent.

12. The method for manufacturing a display device according to claim 11, wherein: The auxiliary solvent includes at least one of ethanol, methanol and isopropanol.

13. The method for manufacturing a display device according to claim 11, wherein: The organic solvent includes an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent or a ketone solvent, but does not include an ethanol solvent.

14. The method for manufacturing a display device according to claim 11, wherein: The step of providing the anti-drying layer includes the step of coating the anti-drying layer in a manner that fully covers at least one of the preliminary functional layers and the pixel defining film.

15. The method for manufacturing a display device according to claim 11, wherein: At least one of the preliminary functional layers comprises a preliminary luminescent layer, The functional layer material is an organic electroluminescent material or a quantum dot material.

Images