JP2011049028A - Manufacturing method of organic el device and manufacturing method of color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve uniformity of layer thickness of a function layer formed in an inkjet method. <P>SOLUTION: The manufacturing method of the organic EL device, provided with organic EL elements 29 each equipped with a first electrode 45, a second electrode 47, and a light-emitting function layer 44 containing at least an organic EL layer 42 pinched by the first electrode 45 and the second electrode 47, comprises a first process of forming a plurality of first electrodes 45 on a substrate 10, a second process of forming barrier ribs 77 surrounding each of the first electrodes 45, a third process of forming a first ink layer 11 by discharging first ink containing a light-emitting function-layer forming material as a solute or a dispersoid in an area 75 surrounded by the barrier ribs 77, a fourth process of forming a second ink layer 12 covering the first ink layer 11 by discharging second ink with a specific gravity smaller than that of the first ink in the area 75 surrounded by the barrier ribs 77, and a fifth process of drying the first ink and the second ink. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic EL device and a method for manufacturing a color filter.

  In recent years, organic EL (electroluminescence) devices have attracted attention as display devices used for large-screen FPDs (flat panel displays). In general, an organic EL device is formed by regularly arranging organic EL elements, which are formed by laminating an anode, a light emitting functional layer including at least an organic EL material layer, and a cathode on a substrate.

  As a method for colorizing an organic EL device, a method combining an organic EL element that emits white light and a color filter, and three kinds of organic EL elements corresponding to three primary color lights (red light, green light, and blue light) There is a method of regularly arranging. In the latter method, it is necessary to form an organic EL layer (organic EL material layer) containing different materials for each of the three types of organic EL elements. When the above-mentioned organic EL material is a low molecular type, it can be formed by a vacuum film forming method such as an evaporation method. Therefore, a mask vapor deposition method (or mask sputtering method) in which a mask having openings corresponding to the pixel regions of the respective organic EL elements is placed on the substrate and an organic EL material is deposited over the mask has been studied. On the other hand, when a polymer type organic EL material is used, it is impossible to apply the vacuum film forming method. Therefore, a droplet of ink containing an organic EL material (that is, a liquid material) is ejected into a partition formed so as to surround the pixel region of the organic EL element, and the ink is dried for each organic EL element. An inkjet method for individually forming an organic EL layer has been studied. The ink jet method can eject droplets having a diameter of the order of μm with high resolution, and thus enables high-definition patterning of organic EL materials. Therefore, it is also used for forming the color filter described above.

  One problem with the inkjet method is the uniformity of the layer thickness. The characteristics of the organic EL layer and the light emitting functional layer including the organic EL layer depend on the layer thickness. Therefore, the layer thickness is required to be highly uniform between the organic EL elements and within the organic EL element. However, since the molecular partial pressure of the solvent (or dispersion medium) evaporated from the ejected droplets is low at the outer edge portion in the coating region on the substrate, that is, the display region 100 (see FIG. 1) described later, it generally dries quickly. Start. Such a difference in drying time may cause a decrease in the uniformity of the layer thickness between the organic EL elements (and within the organic EL element). As described above, since the characteristics of the light emitting functional layer depend on the layer thickness, such a decrease in uniformity can cause a decrease in display quality such as luminance unevenness and light emission color unevenness. Therefore, in order to suppress such a decrease in uniformity, a technique has been introduced in which the above-mentioned partition is formed in the peripheral region of the display region 100 and droplets are ejected to the peripheral region (Patent Document 1). . According to this method, since the variation in the molecular partial pressure in the display region 100 can be reduced, the uniformity of the thickness of the light emitting functional layer due to the variation in the drying time can be improved.

JP 2002-222695 A

  However, since this method forms a partition also around the display device region, it can hinder the enlargement of the screen. Further, there is a problem that it is difficult to obtain an effect when the volatility of the ink is high.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 An organic EL device including a plurality of organic EL elements each including a light emitting functional layer including at least an organic EL layer sandwiched between the first electrode, the second electrode, the first electrode, and the second electrode. A method for manufacturing an apparatus, comprising: a first step of forming a plurality of first electrodes on one surface of a substrate; and a second step of forming a partition surrounding each of the plurality of first electrodes in plan view. And a third step of forming a first ink layer by ejecting a first ink containing a light emitting functional layer forming material as a solute or dispersoid in a region surrounded by the partition, and surrounded by the partition A second step of forming a second ink layer covering the first ink layer by discharging a second ink having a specific gravity smaller than that of the first ink in the region; And a fifth step of drying the ink and the second ink. A method of manufacturing an organic EL device that.

  With such a manufacturing method, it is possible to form a laminate of the first ink layer containing the light emitting functional layer forming material and the second ink layer not containing the light emitting functional layer forming material on the first electrode. Then, after the first ink layer is sequentially formed on the plurality of first electrodes by the second ink layer, the first step is performed during the fifth step, that is, the first ink drying step. The drying of the ink layer can be prevented from proceeding naturally. Therefore, the plurality of first ink layers can be dried under the same conditions. Therefore, the uniformity of the thickness of the light emitting functional layers in the substrate surface can be improved, and a large-screen organic EL device with improved display quality can be obtained.

  Application Example 2 In the above-described organic EL device manufacturing method, the fourth step has a specific gravity smaller than that of the first ink in the region surrounded by the partition walls, and the first ink. A method for producing an organic EL device, comprising the step of discharging the second ink having a higher boiling point to form the second ink layer covering the first ink layer.

  With such a manufacturing method, the second ink layer evaporates and the first ink layer is exposed after the fourth step is completed and before the fifth step is started. It can be further suppressed. Therefore, the plurality of first ink layers can be dried under more preferable conditions, and an organic EL device with further improved display quality can be obtained.

  [Application Example 3] A method for manufacturing an organic EL device as described above, wherein both the first ink and the second ink are mainly composed of an organic liquid. .

  There are various types of organic liquids, and the specific gravity and boiling point can be selected from a wide range. Therefore, with such a manufacturing method, it is possible to use suitable liquids for both the first ink and the second ink. As a result, the plurality of first ink layers can be dried under more preferable conditions, and an organic EL device with further improved display quality can be obtained.

  Application Example 4 In the above-described organic EL device manufacturing method, the first ink uses water as a dispersion medium, and the second ink is an organic liquid. Production method.

  With such a manufacturing method, when the light emitting functional layer forming material is a material that is easily dispersed in water, a light emitting functional layer with high uniformity in layer thickness can be formed.

  Application Example 5 In the above-described organic EL device manufacturing method, the first ink has an organic liquid as a solvent, and the second ink has water as a main component. Device manufacturing method.

  Since water is unlikely to be naturally dried, such a manufacturing method allows the first ink layer to be dried under more favorable conditions, and an organic EL device with further improved display quality can be obtained.

  Application Example 6 An organic EL device including a plurality of organic EL elements each including a light emitting functional layer including at least an organic EL layer sandwiched between the first electrode, the second electrode, the first electrode, and the second electrode. A method for manufacturing an apparatus, comprising: a first step of forming a plurality of first electrodes on one surface of a substrate; and a second step of forming a partition surrounding each of the plurality of first electrodes in plan view. And a first ink containing a light emitting functional layer forming material as a solute or a dispersoid and a second ink having a specific gravity smaller than that of the first ink in a region surrounded by the partition walls. 3. A method for manufacturing an organic EL device, comprising: a third step of ejecting three inks; and a fourth step of drying the first ink and the second ink.

  Inks formed by mixing two types of inks having different specific gravity are separated by the difference in specific gravity as time passes. Therefore, it is possible to form a laminate of the first ink layer containing the light emitting functional layer forming material and the second ink layer not containing the light emitting functional layer forming material on the first electrode by one ejection. Then, the second ink layer can suppress the drying of the first ink layer, and can dry the plurality of first ink layers under the same conditions. Therefore, with such a manufacturing method, it is possible to improve the uniformity of the thickness of the light emitting functional layers in the substrate surface without increasing the number of discharge processes, that is, in one drawing process (discharge process), and display quality is improved. A large-screen organic EL device can be obtained.

  Application Example 7 In the manufacturing method described above, in the third step, the first ink containing a light emitting functional layer forming material as a solute or a dispersoid in a region surrounded by the partition walls, A method for producing an organic EL device, comprising: ejecting an ink obtained by mixing a second ink having a specific gravity smaller than that of the first ink and a boiling point higher than that of the first ink. .

  With such a manufacturing method, it is possible to further suppress the evaporation of the second ink layer and the exposure of the first ink layer before the above-described ejection step is completed. Therefore, the plurality of first ink layers can be dried under more preferable conditions, and an organic EL device with further improved display quality can be obtained.

  Application Example 8 In the above-described organic EL device manufacturing method, the first ink uses water as a dispersion medium, and the second ink is an organic liquid. Production method.

  Since the water and the organic liquid do not dissolve so much, separation after the discharge proceeds rapidly. Therefore, with such a manufacturing method, the first ink layer can be dried under more preferable conditions, and an organic EL device with further improved display quality can be obtained.

  [Application Example 9] A first step of forming a plurality of recesses having one side as a bottom and the partition as a side wall on one surface of a transparent substrate, and a solute or a solute in the recess A second step of ejecting a first ink containing a coloring material as a dispersoid to form a first ink layer; and a second ink having a specific gravity smaller than that of the first ink in the recess. And a third step of forming a second ink layer covering the first ink layer, and a fourth step of drying the first ink layer and the second ink layer. A method for producing a color filter, comprising:

  With such a manufacturing method, a laminate of a first ink layer containing a coloring material and a second ink layer not containing a coloring material can be formed in the recess. Then, after the first ink layer is sequentially formed in the plurality of concave portions by the second ink layer, the first ink layer is formed during the fourth step, that is, the first ink drying step. It is possible to suppress the progress of drying. Therefore, the plurality of first ink layers can be dried under the same conditions. Therefore, the uniformity of the layer thickness of the coloring material in the surface can be improved, and a color filter with improved coloring properties can be obtained.

The circuit block diagram which shows the whole structure of an organic electroluminescent apparatus. The schematic cross section of an organic electroluminescent apparatus. Process sectional drawing which shows the manufacturing method of 1st Embodiment. Process sectional drawing which shows the manufacturing method of 1st Embodiment. Process sectional drawing which shows the manufacturing method of 2nd Embodiment. Process sectional drawing which shows the manufacturing method of 3rd Embodiment. The perspective view which shows the outline | summary of a color filter typically. Process sectional drawing which shows the manufacturing method of 5th Embodiment. Process sectional drawing which shows the manufacturing method of 4th Embodiment.

  Embodiments of an organic EL device manufacturing method according to the present invention will be described below with reference to the drawings. In the following drawings, the scale of each layer and each part is different from the actual scale so that each layer and each part can be recognized on the drawing.

(First embodiment)
Before describing the manufacturing method according to this embodiment, an organic EL device that is a target of the manufacturing method according to this embodiment will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a circuit configuration diagram showing the overall configuration of an organic EL device that is a target of the manufacturing method of the present embodiment. The organic EL device includes a display area 100 and a peripheral area (no symbol) formed in the periphery of the display area. In the display region 100, a plurality of scanning lines 103 extending in the X direction, a plurality of signal lines 104 extending in the Y direction, and a plurality of capacitance lines 106 also extending in the Y direction are formed. Yes.

  Three types of organic EL pixels 30 (a red organic EL pixel 30R and a green organic EL) are defined for each rectangular section in which the X direction is defined by the signal line 104 and the capacitor line 106 and the Y direction is defined by the center line of the scanning line 103. Pixels 30G and blue organic EL pixels 30B) are regularly formed. The alphabet represents the color of light emitted from each organic EL pixel 30. As shown in the drawing, the three types of pixels are regularly formed in the order of R, G, and B in the X direction, and pixels of the same color are arranged in the Y direction. In the following description, when the corresponding colors are not distinguished, they are simply referred to as “organic EL pixels 30”.

  The organic EL device is an active matrix display device. Each organic EL pixel 30 holds a switching TFT (thin film transistor) 108 to which a scanning signal is supplied to the gate electrode via the scanning line 103 and an image signal supplied from the signal line 104 via the switching TFT 108. The storage capacitor 110, the driving TFT 112 to which the image signal held by the storage capacitor 110 is supplied to the gate electrode, the organic EL element 29 in which the driving current flows from the capacitor line 106 through the driving TFT 112, and the like. The organic EL pixel 30 is a functional concept including the above-described elements.

  In the peripheral region, a scanning line driving circuit 120 and a signal line driving circuit 130 are formed. The scanning line driving circuit 120 sequentially supplies scanning signals to the scanning lines 103 in accordance with various signals supplied from an external circuit (not shown). The signal line driver circuit 130 supplies an image signal to the signal line 104. A pixel driving current is supplied to the capacitor line 106 from an external circuit (not shown). The operation of the scanning line driving circuit 120 and the operation of the signal line driving circuit 130 are synchronized with each other by a synchronization signal supplied from an external circuit via the synchronization signal line 140.

  When the scanning line 103 is driven and the switching TFT 108 is turned on, the potential of the signal line 104 at that time is held in the holding capacitor 110, and the level of the driving TFT 112 is determined according to the state of the holding capacitor 110. Then, a drive current flows from the capacitor line 106 into the organic EL element 29 via the drive TFT 112. The organic EL element 29 includes a light emitting functional layer 44 (see FIG. 2) including at least the organic EL layer 42 (see FIG. 2) between a pair of electrodes, and emits light according to the magnitude of the drive current flowing in. The color of the light emission is determined by the material of the organic EL layer.

  FIG. 2 is a diagram schematically showing a cross section in the Y direction of the organic EL device being formed, specifically, the organic EL device at the stage where the organic EL element 29 is formed. A cross section of an organic EL element 29 and a driving TFT (hereinafter referred to as “TFT”) 112 provided in each of the three types of organic EL pixels 30 is shown. In this figure, the switching TFT 108 and the storage capacitor 110 are not shown. Also, the illustration of the respective layers such as the passivation layer formed in the Z (−) direction of the cathode (common electrode) 47 as the second electrode and the counter substrate sandwiching the organic EL element together with the element substrate 10 is omitted. Yes. Hereinafter, description will be made in order from the element substrate 10 side. In the following description, the above direction is referred to as “upward”, “upper”, or “upper layer”.

  The TFT 112 is formed on the element substrate 10. A separate protective layer may be formed at the interface with the element substrate 10. The TFT 112 includes a semiconductor layer 31, a gate electrode 33, and a gate insulating layer 70 formed between the semiconductor layer 31 and the gate electrode 33. A region of the semiconductor layer 31 that overlaps with the gate electrode 33 is a channel region 38, and a source region 35 and a drain region 36 are formed on both sides of the channel region.

  An interlayer insulating layer 71 made of silicon nitride or silicon oxide is formed on the TFT 112. The source region 35 is electrically connected to the source electrode 53 through a contact hole (without reference numeral) formed by locally etching the interlayer insulating layer 71. Similarly, the drain region 36 is connected to the interlayer insulating layer 71. Is electrically connected to the drain electrode 54 through a contact hole (not shown) formed by locally etching the electrode. A planarizing layer 72 made of silicon nitride is disposed on the source electrode 53 and the drain electrode 54. A reflective layer 48 and a protective layer 74 are formed in a predetermined region in the upper layer of the planarizing layer 72, and further, a pixel electrode (first electrode) is formed so as to cover the laminate of the reflective layer and the protective layer. Anode) 45 is formed.

  The pixel electrode 45 needs to have a work function higher than that of the cathode 47 and have conductivity. In the organic EL device according to the present embodiment, the pixel electrode 45 is made of ITO (indium tin oxide alloy) which is a transparent conductive material. Since the organic EL device according to the present embodiment is a top emission type that emits light in the upward direction, a reflective layer 48 that reflects light in the direction is disposed. Note that when the pixel electrode 45 is formed of a reflective metal material, the reflective layer 48 is not required. The reflective layer 48 is preferably formed of Al (aluminum) or the like. The protective layer 74 is made of silicon nitride or the like, and functions to protect the reflective layer 48 when the pixel electrode 45 is formed.

  A partition wall 77 is disposed between the adjacent pixel electrodes 45 so as to surround the pixel electrodes in plan view. A region surrounded by the partition wall is a recess 75. The partition wall 77 includes a lower partition wall 78 on the element substrate side and an upper partition wall 79 as an upper layer. As will be described later, the lower partition 78 is made of silicon oxide, and the upper partition 79 is made of an organic material such as acrylic resin.

  In the recess 75, the hole injection transport layer 43 and the organic EL layer 42 are formed in this order. The hole injection transport layer 43 is common among the three types of organic EL pixels 30. On the other hand, the organic EL layer includes different materials for each of the three types of organic EL pixels 30, and layers that emit light of different colors are formed. Specifically, a red organic EL layer 42R that emits red light is formed in the red organic EL pixel 30R, a green organic EL layer 42G that emits green light is formed in the green organic EL pixel 30G, and a blue organic EL A blue organic EL layer 42B that emits blue light is formed in the pixel 30B. In the following description, when the color of emitted light is not distinguished, it is simply referred to as “organic EL layer 42” as a general term. In addition, in the following description, when any of R, G, and B is added to other components, they are components corresponding to the color (R = red, G = green, B = blue). Shall.

  A laminate of the hole injection transport layer 43 and the organic EL layer 42 is the light emitting functional layer 44. That is, the two layers described above are locally formed in the recess. The cathode 47 is formed on the entire upper surface of the element substrate 10 including the upper layer of the two layers and the upper layer of the partition wall 77. The organic EL element 29 includes a pixel electrode 45, a cathode 47, and the above-described light emitting functional layer 44 sandwiched between the pair of electrodes. Light emission occurs when the holes supplied through the hole injection / transport layer 43 and the electrons supplied from the cathode 47 are combined in the organic EL layer. A part of the light emission is directly reflected, and part of the light is reflected by the reflection layer 48 and emitted toward the cathode 47. The cathode 47 is made of Al (aluminum) or MgAg (magnesium / silver) alloy having a layer thickness of several nm to several tens of nm, and has both conductivity and transparency.

  Since the color of light emitted from each organic EL pixel 30 is determined by the forming material of the organic EL layer 42, the forming material differs between the organic EL pixels. On the other hand, the material for forming the hole injecting and transporting layer is common to each organic EL pixel 30. In addition, there is also an embodiment in which the hole injection / transport layer 43 is formed by being divided into a hole injection layer and a hole transport layer. There is also an aspect in which an electron transport layer or an electron injection layer is formed between the cathode 47 and the organic EL layer 42.

  As described above, the hole injection transport layer 43 and the organic EL layer 42 are locally formed in the recess 75. Such a local layer is formed by the ink jet method in the manufacturing method according to the present embodiment. The inkjet method is a method of forming a layer made of the solid component by discharging a liquid material in which a solid component is dissolved or dispersed in a solvent or a dispersion medium, and then drying and removing the solvent or the dispersion medium. In the present embodiment and each embodiment described later, the liquid material containing the above-described solid component and the liquid-only material not containing the solid component are both referred to as “ink”.

  The ink jet method is a method capable of forming a local layer (that is, patterning) at a lower cost than a photolithography method or the like. However, as described above, there is a problem that the uniformity of the layer thickness is reduced due to the difference (variation) in the drying speed (time) of the solvent (or dispersion medium). In the manufacturing method according to this embodiment, as shown below, the two layers of ink are formed in the above-described recesses, and then the above-described drying and removal are performed, thereby improving the uniformity of the layer thickness.

  3A to 3D and FIGS. 4A to 4D are process cross-sectional views illustrating the manufacturing method of the first embodiment of the present invention. Hereinafter, it will be described in the order of steps.

  First, as shown in FIG. 3A, as a first step, the pixel electrode 45 is formed on the element substrate 10 (upper layer). In FIG. 4 and FIGS. 4 to 6, the components such as the TFT 112 (see FIG. 2) and the reflective layer 48 (see FIG. 2) formed between the element substrate 10 and the pixel electrode 45 are not shown. The illustration is such that the pixel electrode 45 and the partition wall 77 are formed on the element substrate 10 and omitted. The pixel electrode 45 is made of ITO as described above, and is formed by forming a thin ITO film by sputtering or the like and then patterning by photolithography.

  Next, as shown in FIG. 3B, a partition wall 77 is formed so as to surround the pixel electrode 45 in a plan view as a second step. The pixel electrodes 45 are patterned in an island shape having a predetermined distance from each other in plan view. Therefore, by forming the partition wall 77, a recess 75 is formed on the pixel electrode 45 with the pixel electrode as a bottom (bottom surface) and the partition wall 77 as a side wall (side surface). As described above, the partition wall 77 of this embodiment has a two-layer structure of the lower partition wall 78 made of silicon oxide and the upper partition wall 79 made of acrylic resin. However, the partition wall 77 does not necessarily have a two-layer structure. The present invention can also be implemented using a single-layer partition wall 77.

  The lower partition 78 is formed by patterning a silicon oxide thin film formed by a CVD method or the like by a photolithography method. The upper partition wall 79 is also formed by patterning an acrylic resin thin film formed by spin coating or the like by photolithography. Here, when a photosensitive acrylic resin is used for the acrylic resin, the resist coating step can be omitted.

Next, as shown in FIG. 3C, the entire surface of the element substrate 10 is irradiated with CF ₄ plasma 17. By such irradiation, carbon contained in the acrylic resin constituting the upper partition 79 reacts with chlorofluorocarbon in the plasma to become a fluorocarbon resin. As a result, the surface of the upper partition wall 79 becomes liquid repellent.

Next, as shown in FIG. 3D, the entire surface of the element substrate 10 is irradiated with oxygen plasma 18. By such irradiation, organic residues remaining on the surface of the pixel electrode 45 and the surface of the lower partition 78 are removed. As a result, the surface becomes lyophilic.
In addition, the process can be simplified by omitting at least one of the both plasma irradiation processes described above.

  Next, as shown in FIG. 4A, as a third step, a droplet of the hole injection transport material liquid 21 as the first ink is ejected (dropped) from the inkjet head 19 into the recess 75. Thus, the first ink layer 11 that is a liquid layer made of the first ink is formed in the recess 75. The inkjet head 19 has a plurality of minute nozzle holes on the droplet discharge surface, and can discharge a minute ink droplet from the nozzle hole by the piezoelectric effect.

  The hole injection / transport material liquid 21 is a liquid material (liquid material) in which PEDOT / PSS, which is a material for forming the hole injection / transport layer, is dispersed in water as a dispersion medium. The main component of the hole injecting and transporting material liquid 21 is water, and the amount (concentration) of PEDOT / PSS as a dispersoid is small. Therefore, the specific gravity of the first ink is approximately 1.0. In addition, since the boiling point of the first ink can be considered as the boiling point of the solvent or dispersion medium of the ink, water has a boiling point, that is, approximately 100 ° C.

  In each embodiment to be described later, the first ink contains a solute or a dispersoid like the hole injection transport material liquid 21. However, the boiling point and specific gravity of the solvent or dispersion medium are used as they are regardless of the solute and the like. Further, even when the ink (the first ink and the second ink described later) contains two types of liquid, the specific gravity can be calculated by a weighted average. As the boiling point, the numerical value of the liquid as the main component can be used.

  When the area of the droplet discharge surface of the inkjet head 19 is equal to or larger than the area of the element substrate 10, the droplets can be discharged into all the recesses 75 simultaneously. However, when the area of the above-described droplet discharge surface is smaller than the area of the element substrate 10, droplets are discharged while the inkjet head 19 is scanned to sequentially form ink layers in the recesses 75. This figure shows such a case. The ink-jet head 19 is scanned as indicated by broken or solid arrows to sequentially form ink layers (first ink layer 11).

  Next, as shown in FIG. 4B, as a fourth step, a droplet of cyclohexylbenzene 22 as the second ink is ejected (dropped) into the recess 75 to be formed in the recess 75. A second ink layer 12 made of cyclohexylbenzene 22 as a second ink is formed on the first ink layer 11. Unlike the first ink, the second ink contains no solute or dispersoid. That is, the second ink consists only of liquid. In addition, it is necessary to implement this process immediately without leaving time after implementing the above-mentioned 3rd process.

  The second ink needs to have a specific gravity smaller than that of the first ink. Moreover, it is preferable that the boiling point is higher than the boiling point of the first ink. Cyclohexylbenzene has a boiling point of approximately 240 ° C. and a specific gravity of approximately 0.94. Therefore, both the above conditions are satisfied.

  The second ink is not limited to the above-described cyclohexylbenzene, and any nonaqueous organic solvent (nonaqueous organic liquid) having a specific gravity smaller than that of water can be used. Regarding the boiling point, it is not always necessary that the boiling point of the second ink is higher than that of the first ink. Therefore, if the specific gravity is smaller than the specific gravity of water, that is, 1.0, a non-aqueous organic solvent having a boiling point of 100 ° C. or less can be used.

  The cyclohexyl benzene 22 as the second ink is also ejected in the same manner as the hole injection transport material liquid 21. That is, when the area of the droplet discharge surface of the inkjet head 19 is smaller than the area of the element substrate 10, the droplets are discharged while the inkjet head 19 is scanned, and the second ink layer 12 is sequentially inserted into each recess 75. Form. In such a case, cyclohexyl as the second ink is formed before the first ink layer 11 made of the hole injection / transport material liquid 21 as the first ink is formed in all the recesses 75 on the element substrate 10. The discharge of benzene 22 may be started.

  As described above, the second ink needs to be ejected immediately after the first ink is ejected. Therefore, the ink jet head 19 that ejects the first ink and the ink jet head 19 that ejects the second ink are simultaneously driven to perform the two steps of the third step and the fourth step with respect to the individual recesses 75. Are carried out continuously, that is, with as little time as possible. That is, performing the fourth step after the third step is for each recess 75, and the third step and the fourth step are performed simultaneously for the entire element substrate 10. May be. In such a case, on the element substrate 10, the recess 75 in which both the first ink layer 11 and the second ink layer 12 are formed, and the first ink layer 11 is formed and the second ink layer 12 is not yet formed. The formed concave portions 75 and the concave portions 75 in which the first ink layer 11 is not formed are mixed with the concave portions 75 in different stages (states).

  Further, the first ink and the second ink are not necessarily ejected using different ink jet heads 19. Using the inkjet head 19 provided with two sets of ink supply systems, the first ink and the second ink can be successively ejected from different nozzles.

  FIG.4 (c) is a figure which shows the aspect at the time of complete | finishing both the process of a 3rd process and a 4th process. In the recess 75, the first ink layer 11 made of the hole injection / transport material liquid 21 as the first ink and the second ink layer 12 made of cyclohexylbenzene 22 as the second ink are formed to overlap each other. Has been.

  In this state, the second ink has a specific gravity smaller than that of the first ink, so that the above-described two ink layers are prevented from intermingling. In addition, since the second ink has a high boiling point, evaporation at room temperature and normal pressure, that is, natural drying is suppressed. Therefore, although the first ink layer 11 covered with the second ink layer 12 is made of a liquid material having a relatively low boiling point, evaporation is suppressed.

Next, as shown in FIG. 4D, as the fifth step, water that is the dispersion medium of the first ink and cyclohexylbenzene 22 that is the second ink are removed by drying. As a result, a PEDOT / PSS layer that is a dispersoid of the first ink is formed in the recess 75, that is, in the upper layer of the pixel electrode 45. Such a layer is the hole injection transport layer 43. The drying is performed by promoting evaporation by reducing the pressure. Specifically, it is dried for 20 minutes while maintaining a pressure of 4 × 10 ⁻⁴ Pa with a scroll pump. The dry removal conditions described above are not limited to the above numerical values, and heating and reduced pressure may be combined.

  According to the present embodiment, the liquid layer of the hole injecting and transporting material liquid that will become the hole injecting and transporting layer 43 in the future, that is, the first ink layer 11 is the time until the fifth step, that is, the dry removal step. Then, it is covered with the second ink layer 12. Therefore, natural drying of the first ink layer is suppressed during the above-described time. In the fifth step, drying is started on the entire area of the element substrate 10 at the same time and under substantially the same conditions. The same applies to the individual recesses 75, and the drying of the first ink layer 11 is performed simultaneously and substantially under the same conditions in both the region close to the partition wall 77 and the central portion (of the recess 75) in plan view. Be started.

  As described above, the variation in the drying time due to the difference in the drying conditions reduces the uniformity of the thickness of the thin film formed by the drying. Such a decrease in uniformity reduces the display quality of the organic EL device. According to the manufacturing method of the present embodiment, the first ink layer 11 is covered with the second ink layer 12 so as not to expose the surface until the drying and removal process is started from the discharge of the droplets. Therefore, variation in drying time (drying conditions) can be reduced. Therefore, according to the manufacturing method of the present embodiment, it is possible to obtain an organic EL device in which the thickness of the hole injection transport layer 43 is highly uniform and the display quality is improved.

  The layer thickness of the second ink layer 12 does not need to be the same over the entire surface of the element substrate 10 and may be changed as appropriate. In the fifth step, that is, the solvent or dispersion medium drying and removing step, the drying of the first ink layer 11 is started even in the state of being covered with the second ink layer 12, but the full-scale drying is the first. The process proceeds after the second ink layer 12 is removed. Therefore, in order for the drying of the first ink layer 11 to be performed under the same conditions in the plane of the element substrate 10, the drying and removal of the second ink layer 12 is simultaneously completed in the plane of the element substrate 10. It will be necessary.

  On the other hand, since the surface of the second ink layer 12 is always exposed, natural drying occurs immediately after ejection. Therefore, when the area of the droplet discharge surface of the inkjet head 19 is smaller than the area of the element substrate 10, the thickness of the second ink layer 12 that is initially formed is increased, and the fourth step, that is, By gradually reducing the thickness of the second ink layer 12 as the formation process proceeds, the in-plane uniformity of the thickness of the second ink layer 12 at the time when the fifth process, that is, the dry removal process is started can be improved. . As a result, it is possible to form the hole injecting and transporting layer 43 with further improved layer thickness uniformity, and to obtain an organic EL device with further improved display quality.

  Further, the second ink layer 12 formed in the concave portion 75 located outside in the plane of the element substrate 10 is thickened, and the second ink layer formed in the concave portion 75 located in the central portion. No. 12 may be made thinner. After the formation of the second ink layer 12 is completed, the second ink layer 12 is naturally dried before the drying and removal step is started. In that case, the vapor density of the second ink (in this embodiment, cyclohexylbenzene) is higher in the central portion. Therefore, the rate of progress of the natural drying decreases at the central portion.

  In such a case, the decrease in the natural drying rate can be offset by reducing the thickness of the second ink layer 12 at the center of the element substrate 10. Therefore, the layer thickness at the time of starting the dry removal process can be made uniform. As a result, the drying conditions of the first ink layer 11 can be made more uniform, and an organic EL device with further improved display quality can be obtained.

  In the present embodiment, water and cyclohexylbenzene 22 which is a non-aqueous organic solvent as the second ink are combined as a dispersion medium for the hole injection and transport material liquid 21 as the first ink. However, the liquid used in the ink is not limited to such a combination, and a combination of a non-aqueous organic solvent (organic liquid) as the solvent of the first ink and water (or an aqueous solvent) as the second ink is also possible. Is possible. Moreover, both can also be used as a non-aqueous organic solvent. However, it is not possible to use water (or an aqueous solvent) for both because the specific gravity is substantially the same.

  In the present embodiment, cyclohexylbenzene 22 having a specific gravity lower than that of water and having a higher boiling point is combined with water as a dispersion medium for the first ink as the second ink. However, the boiling point of the second ink is not necessarily higher than the boiling point of the liquid that is the main component of the first ink. If the second ink layer 12 completely covers the first ink layer 11 in the recess 75 and this state is maintained during the fifth step, that is, the dry removal step, the first ink layer 11 can be dried under the same conditions. Therefore, even if a liquid having a boiling point lower than that of water is used for the second ink, the effect of the present invention can be obtained.

  In this embodiment, the hole injecting and transporting layer 43 is formed on the pixel electrode 45, but the hole injecting and transporting layer may be divided into a hole injecting layer and a hole transporting layer. It is possible by repeating the 3rd-5th process of the said embodiment twice.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. 5A to 5D are process cross-sectional views illustrating the manufacturing method of the second embodiment of the present invention. This embodiment relates to the formation of the organic EL layer 42 formed on the hole injection / transport layer 43 of the organic EL element 29 provided in the organic EL device, more specifically, the red organic EL layer 42R. The organic EL device itself is the same as that described in the first embodiment. Therefore, in the present embodiment and a third embodiment to be described later, description of the configuration of the organic EL device is omitted. Also, the reference numerals of the components of the organic EL device (for example, the element substrate 10) are the same as those in the first embodiment.

  Note that this embodiment and the first embodiment described above are independent of each other. Therefore, regardless of the first embodiment, the organic EL layer 42 is formed on the hole injection transport layer 43 formed using the conventional technique (manufacturing method) using the manufacturing method according to the present embodiment. You can also Hereinafter, it will be described in the order of steps.

  First, as shown in FIG. 5A, a pixel electrode 45 is formed on the element substrate 10 as a first step, and a partition wall 77 surrounding the pixel electrode in plan view is formed as a second step. Then, the hole injection transport layer 43 is formed on the upper layer of the pixel electrode 45. As described above, the hole injection / transport layer 43 may be formed by the method according to the first embodiment described above, or may be formed by another method.

Next, as shown in FIG. 5B, as a third step, an organic EL serving as the first ink from the inkjet head 19 is inserted into the recess 75 having the partition wall 77 as a side surface and the hole injection / transport layer 43 as a bottom surface. The material liquid 23 is discharged to form the first ink layer 11 in the recess. The organic EL material liquid 23 is a poly [{2-methoxy-5- (2-ethylhexyloxy) -1,4- (1-cyanovinylenephenylene)}-which is a red organic EL material (an organic EL material that emits red light when energized). co- {2,5-bis (N, N'-diphenylamino) -1,4-phenylene}] as a solute and P-chlorotoluene as a solvent.
P-chlorotoluene has a boiling point of 162 ° C., a specific gravity of 1.07, and a solute concentration of 1.5% by weight. Such boiling point and specific gravity become the boiling point and specific gravity of the first ink.

  Next, as shown in FIG. 5C, as a fourth step, pentylbenzene 24 as the second ink is discharged into the recess 75, and the organic EL material liquid 23 formed in the recess 75 is discharged. A second ink layer 12 made of pentylbenzene 24 is formed on the upper layer of the first ink layer 11.

  Pentylbenzene has a boiling point of 205 ° C. and a specific gravity of 0.86. Similar to the first embodiment described above, the pentylbenzene 24 as the second ink does not contain a solute. That is, the pentylbenzene 24 as the second ink is composed only of a liquid. Therefore, in the above-described two steps, the first ink layer 11 containing the organic EL material in the recess 75 and a higher boiling point and lower specific gravity than the solvent of the first ink layer 11 covering the first ink layer. And a second ink layer 12 made of the liquid. Since the second ink layer 12 formed in the upper layer is a liquid having a lower specific gravity, the above-mentioned two layers are maintained without being mixed.

  Similar to the first embodiment described above, this step needs to be carried out immediately without taking time after the third step. Therefore, when the droplet discharge surface of the inkjet head 19 is small, the fourth step may be started before the third step is completed on the entire surface of the element substrate 10. In the individual recesses 75, it is important that the third step and the fourth step are performed continuously, that is, immediately without taking time.

Next, as shown in FIG. 5D, in the fifth step, P-chlorotoluene, which is the solvent of the organic EL material liquid 23 as the first ink, and pentylbenzene 24, which is the second ink, are dried. Remove. The drying method is the same as that in the first embodiment, and the drying is performed under a reduced pressure of 4 × 10 ⁻⁴ using a scroll pump.

  By this step, an organic EL layer 42 made of an organic EL material that is a solute of the first ink, specifically a red organic EL layer 42R, is formed on the hole injection / transport layer 43. A laminate of the organic EL layer 42 and the hole injecting and transporting layer 43 is the light emitting functional layer 44.

  According to the present embodiment, similarly to the first embodiment described above, the first ink layer 11 can be dried simultaneously and substantially under the same conditions in the element substrate 10 and in the individual recesses 75. it can. As a result, it is possible to obtain an organic EL device with high uniformity of the layer thickness of the organic EL layer 42 and improved display quality. The layer thickness of the second ink layer 12 is the same as that of the manufacturing method of the first embodiment in that the thickness of the second ink layer 12 may be appropriately changed in the plane of the element substrate 10.

  In the present embodiment, the formation of the red organic EL layer 42R has been described. However, the organic EL layers 42 corresponding to the other two colors can be formed by the same method. In such a case, the drying and removing step may be performed for each color, and the drying and removing step is performed after forming the first ink layer 11 containing three types of organic EL materials corresponding to three colors, that is, three colors. Different types of organic EL layers 42 (R, G, B) may be formed simultaneously.

  The second ink is the same as the first embodiment in that the boiling point does not necessarily have to be higher if the specific gravity is lower than that of the first ink. Further, the first ink and the second ink are the same as in the first embodiment in that various combinations are possible as long as they are not combinations of water (aqueous solvents).

(Third embodiment)
Next, a third embodiment of the present invention will be described. 6A to 6D are process cross-sectional views illustrating the manufacturing method of the third embodiment of the present invention. This embodiment shows a case where three types of organic EL layers 42 corresponding to three colors of R, G, and B are simultaneously formed on the hole injection transport layer 43. Hereinafter, the steps will be described in the order of steps.

  First, as shown in FIG. 6A, a pixel electrode 45 and a partition wall 77 surrounding the pixel electrode in plan view are formed on the element substrate 10, and a hole injection / transport layer 43 is formed on the pixel electrode 45. Form. The hole injecting and transporting layer 43 may be formed by using the method according to the first embodiment, or may be formed by a conventional method.

  Next, as shown in FIG. 6B, as the third step, the organic EL material liquid 23 as the first ink of the three types is ejected from the inkjet head 19 onto the hole injection transport layer 43 to form the first step. The ink layer 11 is formed. The added alphabet indicates the emission color of the organic EL material which is the solute of the organic EL material liquid 23. The solvent of the three types of organic EL material liquid 23 (R, G, B) is P-chlorotoluene that is the same as the solvent of the organic EL material liquid 23 in the second embodiment.

  The red organic EL material that is the solute of the organic EL material liquid 23R is the same as the material used in the second embodiment described above. The green organic EL material that is the solute of the organic EL material liquid 23G is Poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (1,4-benzo- {2,1 ′, 3} -thiadiazole). ]]. The blue organic EL material which is the solute of the organic EL material liquid 23B is Poly [(9,9-dihexylfluorenyl-2,7-diyl) -co- (9,10-anthracene)].

  The ink jet head 19 used in the present embodiment includes four ink supply systems. Therefore, three types of first ink and (one type) of second ink can be ejected simultaneously within a predetermined region on the element substrate 10.

  Next, as shown in FIG. 6C, as a fourth step, pentylbenzene 24 as the second ink is discharged onto the upper layer of the organic EL material liquid 23 as the first ink. A second ink layer 12 is formed. As described above, since the inkjet head 19 used in this embodiment includes a plurality of supply systems, the pentylbenzene 24 can be discharged from a nozzle formed at a position close to the nozzle from which the organic EL material liquid 23 is discharged. Therefore, the pentylbenzene 24 as the second ink can be continuously discharged by slightly moving the inkjet head 19 after discharging the organic EL material liquid 23 as the first ink.

  Through this process, the first ink layer 11 containing any one of the three types of organic EL materials in the three concave portions 75 in which three types of organic EL elements will be formed in the future, and the first ink layer And a second ink layer 12 made of a liquid having a higher boiling point and a lower specific gravity than the solvent of the first ink layer 11 is formed.

  Next, as shown in FIG. 6D, as the fifth step, P-chlorotoluene, which is a solvent of the organic EL material liquid 23 as the first ink, and pentylbenzene 24, which is the second ink, are added. Remove to dryness. Then, three types of light emitting functional layers 44 (the same reference numerals) that are laminates of any of the three types of organic EL layers 42 and the hole injecting and transporting layer 43 are formed.

  According to the present embodiment, three types of organic EL material liquids 23 are simultaneously ejected using an inkjet head 19 having a plurality of liquid material supply systems, and pentylbenzene 24 is ejected with almost no gap therebetween. Therefore, the drying and removing process of the solvent and the like can be completed only once, and the man-hour can be reduced. In addition, since the first ink layer 11 and the second ink layer 12 can be continuously formed, natural drying of the solvent of the first ink layer 11, that is, the organic EL material liquid 23 can be reduced. Therefore, according to the present embodiment, an organic EL device in which the uniformity of the layer thickness of the organic EL layer 42 is higher and the display quality is improved can be obtained at low cost.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. 9A to 9D are process cross-sectional views illustrating the manufacturing method of the fourth embodiment of the present invention. The manufacturing method of the present embodiment relates to a process of forming the hole injection / transport layer 43 on the pixel electrode 45 as in the manufacturing method of the first embodiment.

3A to 3D, that is, a step of forming the pixel electrode 45 on the element substrate 10, and a lower partition 78 and an upper partition 79 so as to surround the pixel electrode 45 in plan view. The _four steps of forming the partition wall 77 and forming the recess 75, the step of irradiating the entire surface of the element substrate 10 with the CF ₄ plasma 17, and the step of irradiating the entire surface of the element substrate 10 with the oxygen plasma 18 are the same. is there. Therefore, the state after the above-described four steps will be described.
In the present embodiment, the step of forming the pixel electrode 45 is the first step, and the step of forming the partition wall 77 is the second step. Therefore, the description of this embodiment starts from the third step.

  First, as shown in FIG. 9A, in the third step, the hole injection / transport material liquid 21 as the first ink and the cyclohexylbenzene 22 as the second ink are placed in the recess 75 from the inkjet head 19. The third ink 33 formed by mixing the droplets is ejected (dropped) to form the third ink layer in the recess 75. The hole injection transport material liquid 21 is the same as that used in the first embodiment, and is an ink (liquid material) obtained by dispersing PEDOT / PSS as a dispersoid in water as a dispersion medium.

  FIG. 9B is a diagram showing a state in which a layer made of the third ink 33 is formed in the recess 75. Since the dispersion medium of the first ink, that is, water as the main component and cyclohexylbenzene 22 as the organic solvent do not dissolve each other, they start to be separated from each other in the recess 75 as shown in the drawing immediately after ejection.

  FIG. 9C shows a state in which some time has elapsed from the state shown in FIG. As described above, the specific gravity of cyclohexylbenzene 22 is approximately 0.94, which is lighter than water. Therefore, the third ink is composed of the first ink layer 11 made of the hole injection / transport material liquid 21 in the lower layer (on the pixel electrode 45 side). A second ink layer 12 made of cyclohexylbenzene 22 is formed.

  Next, as shown in FIG. 9 (d), as a fourth step, water and cyclohexylbenzene 22 which are the dispersion medium of the hole injecting and transporting material liquid 21 are removed by drying. As a result, a PEDOT / PSS layer that is the dispersoid of the first ink, that is, the hole injection transport layer 43 is formed in the recess 75, that is, in the upper layer of the pixel electrode 45. The drying conditions are the same as the drying conditions of the first embodiment. The point which may combine heating and pressure reduction is also the same.

  According to this embodiment, the same effect as the manufacturing method of the first embodiment described above can be obtained. That is, the first ink layer 11 and the second ink layer 12 are formed in the concave portion 75, and the first ink layer 11 containing the hole injecting and transporting material is dried until the dry removal step is started. Since the surface can be maintained without being exposed by covering with the second ink layer 12 during this period, variations in drying time (drying conditions) can be reduced. Therefore, according to the manufacturing method of the present embodiment, it is possible to obtain an organic EL device in which the thickness of the hole injection transport layer 43 is highly uniform and the display quality is improved.

  The same effects as those of the manufacturing method of the first embodiment can be obtained without increasing the ink ejection (dropping) step. That is, the hole injection transport material liquid 21 that will be the first ink layer 11 in the future and the cyclohexylbenzene 22 that will be the second ink layer in the future are mixed to form the third ink 33. The above-described laminated body can be formed by a single discharge process. Therefore, it is possible to obtain an organic EL device with improved display quality while suppressing an increase in manufacturing cost accompanying an increase in the number of processes.

  In addition, the manufacturing method of this embodiment is not limited to the formation process of a positive hole injection transport layer, It is used also for formation of the organic EL layer 42 like the manufacturing method of the above-mentioned 2nd Embodiment. You can also. In this embodiment, the water-based ink is used as the first ink. However, the hole-injecting and transporting material liquid using an organic solvent having a specific gravity larger than that of water is used as the first ink, and the second ink is used. A mode in which the third ink 33 is combined with water is also possible. In addition, a mode in which two types of organic solvents having different specific gravities are combined to form the third ink 33 is also possible.

  In the manufacturing method of the present embodiment, the third ink 33 may not be mixed uniformly, or may be separated before being ejected to the recess 75. Such a possibility can be dealt with by applying vibrations such as ultrasonic waves to the third ink 33 before being ejected. Further, it is also possible to adopt a mode in which the first ink and the second ink are divided up to the nozzles of the ink jet head and mixed in the nozzles just before the discharge to form the third ink 33. Furthermore, it is also possible to adopt a mode in which the two types of ink are simultaneously discharged from different nozzles into the recess 75 to form the third ink 33 in the recess and then separated in the recess to form a laminate. .

(Fifth embodiment)
Next, a color filter manufacturing method will be described as a fifth embodiment of the present invention. FIG. 7 is a perspective view schematically showing the function and outline of the color filter that is the subject of this embodiment. FIG. 7 shows a backlight 66 that emits white light 67 as a light source, a liquid crystal panel 60 that functions as an optical shutter, and a color filter 80 that uses the white light 67 as colored light 68. The actual color filter 80 is generally formed on one substrate constituting the liquid crystal panel 60. However, in this figure, in order to explain the function of the color filter, it is shown spaced apart.

  The liquid crystal panel 60 includes a first substrate 61 and a second substrate 62 bonded through a sealant 63, a liquid crystal layer (not shown) sandwiched between the pair of substrates, and the like. It is regularly formed. Both substrates are transparent. The liquid crystal panel 60 is a TN type. A counter electrode is formed on the second substrate 62 to keep the entire surface of the liquid crystal panel 60 at a common potential. An independent pixel electrode (not shown) for each pixel 64 is formed on the first substrate 61. Is formed. By applying a voltage between the pair of electrodes, the orientation of liquid crystal molecules is changed, and the amount of light transmitted from the backlight 66 is controlled. Since the above-described applied voltage can be controlled for each pixel 64, the above-described light transmission amount can be controlled for each pixel 64.

  The color filter 80 includes a color filter layer 81 disposed for each pixel 64 and a black matrix 82 having a light shielding property formed in a mesh shape so as to surround the color filter layer. The color filter layer 81 is a transparent material layer colored in one of R, G, and B, and can emit the irradiated white light 67 as colored light 68 of any of the three primary colors. Since light of any color of R, G, and B is emitted at an arbitrary intensity for each pixel 64, a color image is formed in the direction of the arrow shown in the drawing.

  There are various methods for manufacturing the color filter 80, specifically, a patterning method for the color filter layer 81 including a photolithography method, etc. In the case of the large area color filter 80, the inkjet method is advantageous in terms of cost and the like. . However, in the ink jet method, the same problem as when the organic EL layer 42 is formed, that is, the uniformity of the layer thickness may be reduced. Therefore, in the present embodiment, as in the first to third embodiments described above, the uniformity of the layer thickness of the color filter layer 81 is improved by drying and removing the solvent after forming two ink layers. ing.

  FIGS. 8A to 8E are process cross-sectional views illustrating a method of manufacturing a color filter 80 according to the fifth embodiment of the present invention. A process of forming a color filter layer 81 of any of the three primary colors on one surface (hereinafter referred to as “upper surface”) of the second substrate 62 constituting the liquid crystal panel 60 in the future is shown. Yes.

  First, as shown in FIG. 8A, a black matrix 82 is formed on the upper surface of the second substrate 62 as a first step. The black matrix 82 is formed by patterning a chromium thin film formed on the upper surface by a sputtering method using a photolithography method. The black matrix 82 functions like the partition wall 77 in each of the embodiments described above. Therefore, a recess 75 is formed with the second substrate 62 as the bottom and the side surface surrounded by the black matrix 82.

Although not shown, an organic resin partition that overlaps the black matrix 82 in plan view may be further formed. Even when the height of the chromium thin film is insufficient, it can be compensated by the organic resin partition. Further, after the black matrix 82 is formed, the oxygen plasma 18 may be irradiated as in the above-described embodiments. Furthermore, the CF ₄ plasma 17 and the oxygen plasma 18 may be continuously irradiated after forming a two-layer partition wall of chromium and the organic resin.

  Next, as shown in FIG. 8B, in the second step, the color filter material liquid 25 as the first ink is discharged from the ink jet head (not shown) into the recess 75 to form the color filter material liquid 25. A first ink layer 11 made of is formed. The color filter material liquid 25 is obtained by adding butyl acetate as a low boiling point solvent to a liquid material in which an inorganic pigment of any color of R, G, and B is dispersed in a polyurethane resin oligomer as a dispersion medium. Butyl acetate has a boiling point of approximately 126 ° C. and a specific gravity of approximately 0.88.

  Next, as shown in FIG. 8C, as a third step, the pentylbenzene 26 as the second ink is discharged into the recess 75 to form the second ink layer 12 made of pentylbenzene. . As in the above-described embodiments, the third step is performed immediately after leaving the second step, with as little time as possible.

  By the second step and the third step, a laminated body of the first ink layer 11 and the second ink layer 12 is formed in the recess 75. Since the pentylbenzene 26 constituting the second ink layer 12 has a specific gravity lighter than butyl acetate, which is the main component of the first ink layer 11, the mixing of the two layers is suppressed.

  Next, as shown in FIG. 8D, as the fourth step, the polyurethane resin oligomer and butyl acetate contained in the first ink layer 11 and the pentylbenzene 26 constituting the second ink layer 12 are dried. Remove. And the color filter layer 81 which consists of an inorganic pigment which was dispersoid is formed.

  Next, as shown in FIG. 8E, an overcoat layer 83 and a common electrode (counter electrode) 84 are sequentially formed on the entire surface of the second substrate 62. The overcoat layer 83 is made of a transparent resin material, and the common electrode 84 is made of ITO. Through the above steps, the color filter 80 is formed on the second substrate 62.

  According to the present embodiment, similarly to the above-described embodiments, the drying of the first ink layer 11, that is, the color filter material liquid 25 is simultaneously and substantially equivalent in the second substrate 62 and in the individual recesses 75. Can be done under conditions. As a result, the color filter layer 81 with high uniformity in layer thickness can be formed.

  In the present embodiment, the step of forming the color filter layer 81 of one color of R, G, and B is shown, but the other two colors can be formed by the same method. Further, the three color filter layers 81 may be formed simultaneously. By using an inkjet head equipped with three types of liquid supply systems, the three color filter layers 81 can be formed simultaneously.

  As described above, the color filter layer 81 turns white light transmitted through the color filter layer into colored light. According to the manufacturing method of the present embodiment, the white light 67 emitted from the light source 66 can be colored light with little variation between the pixels 64. Therefore, a liquid crystal panel with improved display quality can be obtained by using the manufacturing method of this embodiment.

As in the above-described embodiments, the ejection amount of the pentylbenzene 26 as the second ink, that is, the layer thickness of the second ink layer may be appropriately changed in the plane of the second substrate 62. . That is, the layer thickness of the second ink layer that is initially formed is increased, and the thickness is gradually decreased as the third step, that is, the step of forming the second ink layer, so that the drying conditions are made more uniform. Thus, the color filter layer 81 having a further improved uniformity of layer thickness can be formed.
The color filter 80 can be combined not only with a liquid crystal panel but also with an organic EL panel using a material that emits white light for the organic EL layer 42.

10 ... the element substrate, 11 ... first ink layer, 12 ... second ink layer, 17 ... CF ₄ plasma, 18 ... oxygen plasma, 19 ... inkjet head, 21 ... hole injection transport material as the first ink Liquid, 22 ... cyclohexylbenzene as the second ink, 23 ... organic EL material liquid as the first ink, 24 ... pentylbenzene as the second ink, 25 ... color filter material liquid as the first ink, 26 ... Pentylbenzene as the second ink, 29 ... Organic EL element, 30 ... Organic EL pixel, 33 ... Third ink, 42 ... Organic EL layer, 43 ... Hole injection transport layer, 44 ... Luminescent functional layer, 45... Pixel electrode (anode) as first electrode 47. Cathode as second electrode 48. Reflection layer 60. Liquid crystal panel 61. First substrate 62. Second substrate 63. Material: 64 ... Pixel, 66 ... Backlight (light source), 67 ... White light, 68 ... Colored light, 70 ... Gate insulating layer, 74 ... Protective layer, 75 ... Recessed area surrounded by the partition, 77 ... Partition 78 ... Lower partition, 79 ... Upper partition, 80 ... Color filter, 81 ... Color filter layer, 82 ... Black matrix, 83 ... Overcoat layer, 84 ... Common electrode.

Claims (9)

A method for producing an organic EL device comprising a plurality of organic EL elements each including a light emitting functional layer including at least an organic EL layer sandwiched between a first electrode, a second electrode, and the first electrode and the second electrode. There,
A first step of forming a plurality of the first electrodes on one surface of the substrate;
A second step of forming a partition wall surrounding each of the plurality of first electrodes in plan view;
A third step of forming a first ink layer by discharging a first ink containing a light emitting functional layer forming material as a solute or a dispersoid in a region surrounded by the partition;
A fourth step of forming a second ink layer covering the first ink layer by discharging a second ink having a specific gravity smaller than that of the first ink in a region surrounded by the partition;
A fifth step of drying the first ink and the second ink;
The manufacturing method of the organic electroluminescent apparatus characterized by the above-mentioned. It is a manufacturing method of the organic EL device according to claim 1,
In the fourth step, the second ink having a specific gravity smaller than that of the first ink and having a boiling point higher than that of the first ink is ejected into a region surrounded by the partition wall, A method for producing an organic EL device, comprising the step of forming the second ink layer covering one ink layer. It is a manufacturing method of the organic EL device according to claim 1 or 2,
The method for manufacturing an organic EL device, wherein both the first ink and the second ink contain an organic liquid as a main component. It is a manufacturing method of the organic EL device according to claim 1 or 2,
The method of manufacturing an organic EL device, wherein the first ink uses water as a dispersion medium, and the second ink is an organic liquid. It is a manufacturing method of the organic EL device according to claim 1 or 2,
The method of manufacturing an organic EL device, wherein the first ink uses an organic liquid as a solvent, and the second ink contains water as a main component. A method for producing an organic EL device comprising a plurality of organic EL elements each including a light emitting functional layer including at least an organic EL layer sandwiched between a first electrode, a second electrode, and the first electrode and the second electrode. There,
A first step of forming a plurality of the first electrodes on one surface of the substrate;
A second step of forming a partition wall surrounding each of the plurality of first electrodes in plan view;
A third ink formed by mixing a first ink containing a light emitting functional layer forming material as a solute or a dispersoid and a second ink having a specific gravity smaller than that of the first ink in a region surrounded by the partition walls. A third step of ejecting ink;
A fourth step of drying the first ink and the second ink;
The manufacturing method of the organic electroluminescent apparatus characterized by the above-mentioned. It is a manufacturing method of the organic EL device according to claim 6,
The third step includes a first ink containing a light emitting functional layer forming material as a solute or a dispersoid in a region surrounded by the partition walls, a specific gravity smaller than that of the first ink, and the first step. A method for producing an organic EL device, comprising: ejecting an ink obtained by mixing a second ink having a boiling point higher than that of the first ink. It is a manufacturing method of the organic EL device according to claim 6 or 7,
The method of manufacturing an organic EL device, wherein the first ink uses water as a dispersion medium, and the second ink is an organic liquid. A first step of forming a partition wall on one surface of the transparent substrate and forming a plurality of recesses having the one surface as a bottom and the partition wall as a side wall;
A second step of forming a first ink layer by discharging a first ink containing a coloring material as a solute or a dispersoid in the recess;
A third step of forming a second ink layer covering the first ink layer by discharging a second ink having a specific gravity smaller than that of the first ink into the recess;
A fourth step of drying the first ink layer and the second ink layer;
A method for producing a color filter, comprising:

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