JP2001284047A - Manufacturing method of an organic electroluminescence display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an organic electroluminescence display device which can produce the organic electroluminescence display device that is simply and easily capable to display high quality color images. SOLUTION: In the case of forming an organic layer by ejecting out the organic material of liquid phase on a substrate by an ink-jet method, this method is constituted from that (a) the image recognition pattern is formed beforehand on the substrate, (b) an information about a position either of a substrate or of a picture element by recognizing the image recognition pattern using an image recognition device, and that (c) based on this substrate or information about the position of picture element, a positioning of an ink-jet head and substrate or the picture element as well as to control a timing when the liquid of organic material is to be ejected are regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an organic electroluminescence (EL) display device, and more particularly, to an organic method comprising forming an organic layer by an ink-jet method using a liquid-phase organic material. The present invention relates to a method for manufacturing an EL display device.

[0002]

2. Description of the Related Art Conventionally, in order to form a light emitting layer in an organic EL device, a wet coating method such as a spin coating method, a dipping method, a roll coating method, a doctor blade, etc. has been applied to the entire surface of an electrode. Membrane method, various printing methods,
Various methods such as an electrodeposition method have been adopted.

However, in the wet method, it is difficult to pattern an organic layer serving as a light emitting layer of an organic EL element for each different color in order to form an organic EL element for color display.

As one method for solving these problems, there has been proposed a technique of patterning a light emitting layer of an organic EL device by an ink jet method (Japanese Patent Laid-Open No. 10-1237).
No. 7, Appl. Phys. Lett. 72, 519, 1998).

According to this method, the light emitting layer can be formed into a thin film using a liquid phase organic material.

However, since a gap is required between the ink jet head and the substrate, when the liquid organic material is ejected from the nozzle of the ink jet head, the landing position of the dot is deviated from the target position. Occurs. Further, it is difficult to control the dot diameter of the organic material discharged from the nozzle with high accuracy. Further, in manufacturing an organic EL display device, the position of a substrate is mechanically controlled using a movable XY table.
In the Y table, a mechanical positioning error, for example, a positioning error of about several tens μm occurs. Therefore, the application of the organic material by the ink-jet method has a problem that it is difficult to form a light emitting layer at a predetermined position with high accuracy due to the variation of the dot diameter of the organic material, the bending of the flight, and the mechanical misalignment. is there.

Therefore, a method of surrounding each pixel with a water- and oil-repellent bank has been proposed (JP-A-11-87062). In this method, after patterning an anode formed on a transparent substrate to form an anode group, a bank is formed between the anode groups, and a charge injection transport layer and / or a light emitting layer is formed between the banks in a liquid phase. In this method, the cathode is formed on the surface.However, since the bank is water- and oil-repellent, that is, its surface is smaller than the critical surface tension of the liquid phase, when forming the liquid phase between the banks, The liquid phase falls within the pixel and does not contaminate adjacent pixels. Further, since the liquid phase does not straddle between the pixels, it is possible to prevent electric leakage between the pixels. Therefore, each pixel can emit light of the color of the organic fluorescent substance used faithfully, and extremely vivid color display can be achieved.

However, even with this method, if the size of the organic EL display device is increased, the mechanical displacement of the substrate position becomes large, and it becomes difficult to separate the liquid phase between pixels. Further, if it is necessary to increase the definition and aperture ratio of the organic EL display device, there arises a problem that there is no space for forming a bank between the anodes.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to manufacture an organic EL display device capable of easily producing an organic EL display device capable of displaying a high-quality color image. The aim is to provide a method.

[0010]

According to the present invention, when an organic layer is formed by discharging a liquid organic material onto a pixel on a substrate by an ink-jet method, (a) an image recognition pattern is previously formed on the substrate. And (b) position information of the substrate or the pixel is obtained by recognizing the image recognition pattern by an image recognition device. (C) Based on the position information of the substrate or the pixel, the ink jet head and the substrate or the pixel are obtained. There is provided a method for manufacturing an organic electroluminescent display device, comprising controlling alignment and timing for discharging a liquid phase organic material.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is a method for forming an organic layer on a pixel on a substrate by an ink-jet method.

The substrate that can be used in the present invention is not particularly limited as long as it is generally used for an EL display device or the like. For example, a substrate made of an inorganic material such as quartz or glass, A film or sheet substrate made of a plastic such as polyester, polymethacrylate, polycarbonate, and polysulfone may be used. The substrate is preferably transparent or translucent so that an image recognition pattern and / or the position of an inkjet head or the like can be recognized through the substrate, as described later. Note that electrodes, insulating layers, various elements, circuits, and the like may be formed in advance on the substrate or during or after the manufacturing process of the organic EL display device.

The ink-jet method in the production method of the present invention generally means a method of discharging a liquid-phase organic material to a predetermined position on a substrate using an ink-jet recording technique, and usually includes an ink-jet printing machine, an ink-jet drawing apparatus, It can be performed using an apparatus called an ink jet machine or the like. Apparatuses for performing the inkjet method include various types such as a charge control system, a divergence system, an electromechanical conversion system, an electrothermal conversion system, and an electrostatic suction system. Also,
The apparatus for performing the inkjet method includes an inkjet head that discharges at least ink (liquid-phase organic material), and optionally includes an inkjet head nozzle, inkjet head position control means, inkjet timing control means, a substrate support, and a substrate position. It is preferable to provide control means and the like.

Further, it is preferable that the ink jet machine is provided with an image recognition device separately or as a part thereof. Examples of the image recognition device include an optical reading device such as a CCD camera. The image recognition device performs image recognition of ink (liquid-phase organic material) ejected onto a substrate by an ink jet machine. can do. It is preferable that the image recognition apparatus can output recognized information, specifically, positional information of a substrate or a pixel based on an image recognition pattern as described later, using a digital signal or an analog signal. Note that the image recognition device may be arranged so that the image on the substrate can be recognized from above the substrate, or when the substrate is transparent or translucent, the image can be recognized on the substrate from below the substrate through the substrate. May be arranged as follows. The area in which the image recognition device can recognize an image may be the entire substrate, or may be a part of the substrate, for example, only a screen formed by pixels, or one or more pixels. Further, it is preferable that the region in which the image can be recognized by the image recognition device is a region including pixels from which the liquid organic material is discharged by the image recognition.

The liquid-phase organic material used in the present invention refers to an organic material which can be coated on a substrate by an ink-jet method by using an appropriate solvent such as chloroform, dichloromethane, tetrahydrofuran, dioxane, xylene, alcohols or the like. Means a coating solution dissolved or dispersed in

The organic material is, for example, an organic light-emitting material, a material obtained by combining a hole transport material, an electron transport material, and / or a dopant with the organic light-emitting material; A material in which a polymer material or an inorganic material is further added to an organic light emitting material or a combined material so as to be dispersed therein. In particular, since a film is formed by a wet process, a material in which a polymer material is further added to an organic light emitting material or a combined material is preferable.

The organic light-emitting material is not particularly limited as long as it is generally used as a light-emitting material of an organic EL device. For example, a metal oxinoid compound (8-hydroxyquinoline metal complex), naphthalene Derivative, anthracene derivative, diphenylethylene derivative, vinylacetone derivative, triphenylamine derivative, butadiene derivative, coumarin derivative, benzoxazole derivative, oxadiazole derivative, oxazole derivative, benzimidazole derivative, thiadiazole derivative, benzothiazole derivative, styryl derivative, Styrylamine derivatives, bisstyrylbenzene derivatives, tristyrylbenzene derivatives, perylene derivatives, perinone derivatives, aminopyrene derivatives, pyridine derivatives, rhodamine derivatives, Derivative, phenoxazone, quinacridone derivatives, low molecular materials such as rubrene, poly -p-
Polymer materials such as phenylenevinylene and polysilane are exemplified.

The hole transporting material is not particularly limited as long as it has been conventionally used as a charge transporting material for holes in a photoconductive material or a material used as a hole transporting material in an organic EL device. Without, for example, low-molecular-weight materials such as porphyrin derivatives, aromatic tertiary amine compounds, and styrylamine derivatives; high-molecular-weight materials such as polyvinylcarbazole, poly-p-phenylenevinylene, and polysilane; triazole derivatives, oxadiazole derivatives, Imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amine-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives; Rufasu silicon, hydrogenated amorphous silicon carbide, zinc sulfide, inorganic compounds such as zinc selenide.

The electron transporting material is not particularly limited as long as it has been conventionally used as a charge transporting material for electrons in a photoconductive material or a material used as an electron transporting material for an organic EL device. For example, oxadiazole derivatives, triazole derivatives, thiopyrazine oxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, anthraquinodimethane derivatives, diphenoquinone derivatives, fluorenone derivatives, fluorenylidenemethane derivatives, nitro-substituted fluorenone compounds, silole compounds, etc. Low molecular weight materials.

As the dopant, coumarin dyes, pyridine dyes, rhodamine dyes, aquidine dyes,
Fluorescent dyes such as phenoxazone, DCM, quinacridone, rubrene; Au, Pt, Br, I, 7, 7, 8, 8-
Tetracyanoquinodimethane, trinitrofluorenone,
Acceptors such as bromanyl; donors such as alkali metals, alkaline earth metals, rare earth elements, triphenylamine derivatives, and condensed polycyclic compounds.

The polymer material is not particularly limited as long as it is a polymer material conventionally used in the field, and examples thereof include polyvinyl carbazole, polycarbonate, and polymethyl methacrylate.

The inorganic material is not particularly limited as long as it is an inorganic material conventionally used in the field, and examples thereof include SiO, SiO ₂ , and MgO.

The organic layer can be usually formed by applying the above-mentioned liquid-phase organic material on a substrate and then curing the applied organic material. Examples of the curing method include a heat treatment such as baking. The heat treatment conditions include, for example, a temperature range of about 65 to 350 ° C. in an inert gas atmosphere such as nitrogen,
For example, a processing time of about 120 minutes. The thickness of the organic layer is, for example, about 5 to 5000 nm.

In the manufacturing method of the present invention, first, in step (a), an image recognition pattern is previously formed on a substrate.

The material, shape, film thickness, position and number of the image recognition pattern are not particularly limited as long as they can be recognized by a general image recognition device.

For example, the image recognition pattern includes an electrode material,
It can be formed of any material such as an organic material and an insulating material.

As an electrode material, a material that can be used as a lower electrode or an upper electrode of an organic EL display device, specifically,
Aluminum, vanadium, cobalt, nickel, tungsten, silver, gold, calcium, titanium, yttrium, sodium, ruthenium, manganese, indium, magnesium, lithium, ytterbium, LiF
Metals such as magnesium / copper, magnesium / silver, sodium / potassium, At / AtO ₂ , thiium / aluminum, thiium / calcium / aluminum, LiF
/ Alloys such as calcium / aluminum; CuI, Sn
A transparent conductive material such as O, ZnO, ITO, etc .; Further, the image recognition pattern may be formed as a pattern obtained by hollowing out these materials. Examples of the organic material include the above-described organic materials and the like. Examples of the insulating material include polyimide, polyethylene terephthalate, polyphenylene sulfide, and a photosensitive resist.

The shape of the image recognition pattern is, for example, as shown in FIG.
As shown in the above, a circle; a square such as a square, a rectangle, a trapezoid, and a parallelogram; a polygon; a combination thereof; a hollowed shape thereof; The film thickness is 0.1μ
m to about 10 μm. It should be noted that the height of the pattern when formed as a hollow pattern may be similar.

The position where the image recognition pattern is formed may be any position such as an arbitrary region within a pixel on the substrate, between pixels, an outer peripheral region of a screen formed by the pixels on the substrate, or the like. The number may be, for example, one for each pixel or one for a plurality of pixels when formed in pixels on the substrate. When it is formed between the pixels, one or more may be sufficient. If it is formed in the outer peripheral area of the screen, it suffices if it is two or more. Further, one or more pixels may be formed in the pixel on the substrate and one or more may be formed between the pixels or in the outer peripheral area of the screen. Among them, it is preferable that at least one is formed in a pixel.

In the case where two or more image recognition patterns are formed on the substrate, at least one of the circles virtually created with all the straight lines connecting the two or more image recognition patterns as diameters. It is preferable that all the pixels from which the liquid organic material is discharged are included in one circle.

Next, in step (b), the image recognition pattern is recognized by the image recognition device. Thereby, the position information of the substrate or the pixel can be obtained. If the ink jet head of the ink jet device is fixed or the position information of the ink jet head can be obtained in advance, the position information of the substrate or the pixel with respect to the ink jet head can be obtained by comparing these information. Can be. Even when the position information of the ink jet head is not obtained in advance, when the image recognition device recognizes the image recognition pattern, the ink jet head is recognized at the same time as the recognition of the pattern through the substrate from above or below the pattern. By obtaining the position information and comparing these information, the position information of the substrate or the pixel with respect to the ink jet head can be obtained.

Subsequently, in step (c), based on the positional information of the substrate or the pixel obtained above, the alignment of the ink jet head and the substrate or the pixel and the timing of discharging the liquid organic material are controlled. I do.

Specifically, as shown in FIG.
By moving the substrate by the substrate position control means based on the position information of the substrate or the pixel obtained in the step (b), the optimal position of the substrate or the pixel with respect to the ink jet head, for example, a positional deviation of ± The organic material is ejected from the inkjet head by the inkjet timing control means at the moment when the substrate or the pixel is adjusted to the optimal position while the position is adjusted to the position of about μ or less, preferably ± 5 μm or less, more preferably ± 3 μm or less. It is preferable to perform control so as to perform the control. Note that such control may be performed by fixing the substrate and moving the inkjet head instead of moving the substrate, as shown in FIG. 1B, or FIG. 1C.
As shown in (2), this may be performed by moving both the substrate and the inkjet head.

For example, two or more image recognition patterns are formed on a substrate, and a pixel from which a liquid-phase organic material is ejected is assumed to have a virtual diameter with all the straight lines connecting these two or more image recognition patterns mutually. If at least one of the circles to be drawn is located within the circle, the two or more image recognition patterns are image-recognized, and the substrate ( When the control data including the information on the position of the pixel) is obtained,
By discharging the organic material from the inkjet head, the positional deviation between the head and the discharged pixels can be sufficiently suppressed with respect to the application positional deviation due to the curved flight of the dots. That is, the displacement of the dot application position can be suppressed only to the dot diameter of the liquid phase organic material and the flight bending of the dots, so that the liquid phase organic material can be reliably discharged into desired pixels.

In the present invention, it is preferable to form a lower electrode on a substrate and an upper electrode on an organic layer before, during, or after each step in the above-mentioned manufacturing method. Since the lower electrode and the upper electrode generally function as an anode or a cathode, respectively, it is preferable to select and form an optimum material from the above-mentioned electrode materials. When forming the lower electrode on the substrate, it is preferable to form the image recognition pattern in the above step (a) using the same material and the same step.

In the present invention, it is preferable that a partition layer is formed between regions where pixels are to be formed before applying the liquid organic material onto the substrate. Specifically, after forming a plurality of lower electrodes corresponding to the unit pixels on the substrate, it is preferable to form a partition layer so as to be arranged between the lower electrodes. To form a partition layer, and a lower electrode may be formed in a region on the substrate where the partition layer is not formed. The partition layer can be formed of an insulating material such as polyimide, polyethylene terephthalate, polyphenylene sulfide, and photosensitive resist. The thickness of the partition layer is not particularly limited, but is preferably formed to be thicker than an organic layer formed in a later step, and specifically, about 1 μm to 50 μm. Although the shape of the partition layer is not particularly limited, for example, a shape surrounding the unit pixel so that unit pixels in a normal organic EL display device can be arranged in a matrix,
Specifically, it is appropriate to form a lattice shape. The width, vertical and horizontal pitch, and the like of the partition layer can be arbitrarily set. Due to the presence of such a partition layer, a liquid organic material can be applied only on the substrate in a region surrounded by the partition layer.

In the present invention, the formation of the organic layer on the substrate as described above may be performed only once.
It may be repeated several times. Accordingly, organic layers having different materials, different thicknesses, and different laminated structures can be formed corresponding to each unit pixel, and a plurality of organic layers having different colors corresponding to color display can be formed. Becomes When the organic layer is composed of two or more laminated layers, if at least one of the layers is formed from a liquid-phase organic material by the above method, the other layers are wet. It may be formed by a process or a dry process (for example, a vacuum deposition method, CV
D method, plasma CVD method, dry film forming method such as sputtering method)
May be formed.

Hereinafter, the method for manufacturing the organic EL display device of the present invention will be described in detail. Example 1 First, as shown in FIGS.
A transparent indium tin oxide (hereinafter abbreviated as ITO) film 1 having a thickness of 150 nm is formed on a 1 mm transparent glass substrate 10 by a sputtering method, and a plurality of stripes having a pattern pitch of 50 μm and a pattern width of 38 μm are formed. Patterning was performed on the anode. At the same time, an image recognition pattern 2 having a diameter of 8 μm was formed near the center of each pixel of the ITO film 1.
An m-shaped circular punch pattern was formed.

Next, a photosensitive polyimide film is formed on the obtained glass substrate 10, and a pattern pitch of 50 μm, a pattern width of 15 μm, and a height of 1 μm are formed between the patterned ITO films 1 by a photolithography and etching process.
A partition layer 3 of about 5 μm was formed. The partition layer 3 is made of ITO
In a direction perpendicular to the film 1, a pattern pitch of 150
μm and a pattern width of 25 μm. As a result, each pixel (35 μm × 125 μm) was surrounded by the partition layer 3. The image recognition pattern 2 is located near the center of the pixel.
Is present, but this area is 1.1 to the pixel area.
It is only 5% and does not impair the light emitting function of the organic EL element.

The surface of the ITO film 1 on the obtained glass substrate 10 was washed with UV ozone.

Thereafter, as shown in FIG. 3, the glass substrate 10 is placed with the ITO film 1 upward on a movable transparent XY table below the nozzles of the fixed inkjet head 12. did.

Subsequently, a high magnification CCD is used as an image recognition device.
(Charge coupled device) By recognizing the image recognition pattern 2 in the pixel from the lower side of the glass substrate 10 by the camera 11, the ejected pixel and the positional information of the glass substrate 10 including this pixel were obtained.

Next, this information is output as a digital signal to the XY table and the ink jet machine. This allows
By operating the XY table, the positional deviation between the nozzle of the fixed inkjet head 12 and the pixel from which the organic material is discharged is controlled with an accuracy of ± 3 μm or less, and the positional deviation between the nozzle and the pixel to be discharged is reduced. At the moment of the control, the organic material 13 for forming the red light emitting layer can be discharged from the nozzle into each pixel surrounded by the partition layer 3.
The organic material 13 is prepared by mixing 0.3% by weight of a polyphenylenevinylene (PPV) precursor with 0.02% by weight of rhodamine 101, which is a red fluorescent dye, with respect to PPV to prepare an organic material for forming a red light emitting layer. It was used.
Thereafter, the coating film was cured at 150 ° C. in a nitrogen atmosphere to form a red light emitting layer 4 having a thickness of 50 nm, thereby forming a red pixel.

Next, another liquid-phase organic material was applied to the glass substrate 10 between the partition layers 3 by an ink-jet method in the same manner as described above. As the organic material, a material prepared by preparing a 0.3 wt% polyphenylenevinylene (PPV) precursor as an organic material for forming a green light-emitting layer was used. Thereafter, the coating film is cured at 150 ° C. in a nitrogen atmosphere, and a film thickness of 50 n
m green light emitting layer 5 was formed, and a green pixel was formed.

Further, 0.5 wt% of polydioctylfluorene is prepared as an organic material for forming an electron transport layer and a blue light emitting layer, and this organic material is applied to the entire surface of the glass substrate 10 between the partition layers 3 by spin coating. Applied. Thereafter, the coating film was cured at 150 ° C. in a nitrogen atmosphere to form an electron transport layer and a blue light emitting layer 6 having a thickness of 50 nm, thereby forming a blue pixel.

Subsequently, the obtained glass substrate 10 was set in a chamber of a resistance heating vacuum evaporation apparatus, and at the same time,
The first layer cathode material, Ca, is used for the sublimation material Mo boat.
And Al as the cathode material of the second layer are separately placed,
The glass substrate 1 obtained by evacuating to about 0 ^-6 Torr was obtained.
On cathode 0, a cathode was formed by vacuum evaporation. The cathode was formed by depositing a first Ca layer 7 on the obtained glass substrate 10 with a film thickness of 10
Evaporation was performed at about 0 nm, and a second Al layer 8 was evaporated thereon with a thickness of about 200 nm.

Thus, an XY matrix having a size of 7
5 × 75 mm, screen size 36 mm × 27 mm, number of display dots 240 (80 × RGB) × 180, unit pixel pitch 150 μm (50 μm × RGB) × 150 μm, organic electroluminescence display having basic design values of each pixel size 35 μm × 125 μm The device was formed.

The RGB element structure of this organic electroluminescence display device is such that the red element is ITO (anode) /
PPV + rhodamine 101 (red light emitting layer) / polydioctylfluorene / Ca / Al (cathode), green element is ITO / PPV (green light emitting layer) / polydioctylfluorene / Ca / Al, blue element is ITO / poly Dioctylfluorene (blue light-emitting layer) / Ca / Al, each light-emitting material can be reliably applied to a pixel to be applied by an ink-jet method, and each pixel emits light of its RGB emission color faithfully. Was something.

Example 2 First, as shown in FIG. 4, a transparent glass substrate 20 having a thickness of 1.1 mm was sputtered to a thickness of 15 mm.
A 0 nm ITO film is formed, and the pattern pitch is 50 μm.
Patterning was performed on a plurality of stripe-shaped anodes having a pattern width of 38 μm. At the same time, the image recognition patterns 22 were formed at two diagonal positions on the display screen 21 with ITO patterns. Note that the image recognition pattern 22 is formed at a position including all the pixels from which the organic material is discharged, within a circle 23 virtually drawn with a straight line connecting the two image recognition patterns 22 as the diameter.

Next, a photosensitive polyimide film is formed on the obtained glass substrate, and a pattern pitch of 50 μm, a pattern width of 15 μm, and a height of 15 μm are formed between the patterned ITO films by a photolithography and etching process.
About m partition walls were formed. The partition layer had a pattern pitch of 150 μm and a pattern width of 25 μm in a direction perpendicular to the ITO film. Thereby, each pixel (35 μm
× 125 μm) was surrounded by the partition layer.

The surface of the ITO film of the obtained glass substrate was subjected to UV irradiation.
After ozone cleaning, a glass substrate is placed on the movable transparent XY table below the nozzles of the fixed inkjet head, with the ITO film facing upward, and a high magnification C
By recognizing the image recognition pattern 22 in the pixel from the lower side of the glass substrate 10 by the CD camera 11, the position information of the ejected pixel and the glass substrate including this pixel is obtained, and the nozzle of the fixed inkjet head is By controlling the displacement from the pixel from which the organic material was discharged and the timing of discharging the organic material, a red light emitting layer, a green light emitting layer, and a blue light emitting layer were formed.

Subsequently, in the same manner as in the first embodiment,
A cathode composed of a Ca layer having a thickness of about m and an Al layer having a thickness of about 300 nm is formed.
5 mm, screen size 36 mm x 27 mm, number of display dots 240 (80 x RGB) x 180, unit pixel pitch 15
An organic electroluminescent display device having basic design values of 0 μm (50 μm × RGB pitch) × 150 μm and each pixel size of 35 μm × 125 μm was formed.

The RGB element structure of this organic electroluminescent display device is such that the red element is ITO (anode) /
PPV + rhodamine 101 (red light emitting layer) / polydioctylfluorene / Ca / Al (cathode), green element is ITO / PPV (green light emitting layer) / polydioctylfluorene / Ca / Al, blue element is ITO / poly Dioctylfluorene (blue light-emitting layer) / Ca / Al, each light-emitting material can be reliably applied to a pixel to be applied by an ink-jet method, and each pixel emits light of its RGB emission color faithfully. Was something.

[0054]

According to the present invention, the position information of the substrate or the pixel by the image recognition pattern and the apparatus is obtained, and based on this information, the positioning of the ink jet head and the substrate or the pixel, and the timing of discharging the liquid organic material. By controlling the position, the positional deviation between the inkjet head and the region to be discharged can be sufficiently suppressed with respect to the positional deviation of the application due to the curved flight of the dots, and the liquid organic material should be discharged reliably. Can be applied to the area. This makes it possible to manufacture an organic EL display device capable of displaying a high-quality color image.

In the case where the area recognizable by the image recognition device is within the pixel and the image recognition pattern is formed in the pixel, or when two or more image recognition patterns are formed on the substrate, the two When at least one of the circles virtually created with all the straight lines connecting the above image recognition patterns as diameters includes a pixel from which a liquid-phase organic material is discharged, the inkjet head is used. Position deviation from the area to be ejected can be minimized with respect to the application position shift due to the flight deflection of the dot, and the liquid organic material can be applied to the area to be ejected more reliably. .

Further, when at least one image recognition pattern is formed in a pixel from which the liquid organic material is discharged, the liquid organic material is applied to a region to be discharged more reliably. can do.

In the case where the image recognition pattern is formed of an electrode material, an organic material, and / or an insulating material formed on a substrate, the image recognition pattern may be formed of an electrode constituting an element in an organic EL display device. It can be formed simultaneously with the organic layer and the like, and the manufacturing cost can be reduced without increasing the number of steps.

Further, the substrate is transparent or translucent, and the image recognition device recognizes the image recognition pattern through the substrate, or the substrate is transparent or translucent, and the image recognition device recognizes the image recognition pattern through the substrate. In addition, if the position of the ink jet head is also recognized, a barrier layer thicker than the organic layer is formed in advance between the pixels on the substrate, and the organic material is discharged into a region surrounded by the barrier layer. In this case, it is not necessary to adjust the surface of the constituent material surface of the partition layer to a very special state, for example, to adjust the state to a wet state with an organic material to form the partition layer. Thereby, since the region on the substrate can be divided for each unit pixel, it becomes possible to perform the suction removal of the organic material using the thin tube while reliably or strictly controlling the organic material.
It is possible to manufacture the organic layer uniformly and with high precision,
Production of a high-quality organic EL display device can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining control of alignment of an inkjet head and a substrate or a pixel and timing of discharging a liquid organic material in a method of manufacturing an organic EL display device of the present invention.

FIGS. 2A and 2B are a schematic plan view and a sectional view of a main part of an organic EL display device for describing an example of a method for manufacturing an organic EL display device of the present invention.

FIG. 3 is a schematic process diagram for explaining an embodiment of a method for manufacturing an organic EL display device of the present invention.

FIG. 4 is a schematic plan view of a main part of an organic EL display device for explaining another embodiment of the method for manufacturing an organic EL display device of the present invention.

FIG. 5 is a diagram showing the shape of an image recognition pattern used in the method for manufacturing an organic EL display device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ITO film 2, 22 Image recognition pattern 3 Partition layer 4 Red light emitting layer 5 Green light emitting layer 6 Electron transport layer and blue light emitting layer 7 Ca layer 8 Al layer 10, 20 Glass substrate (substrate) 11 High magnification CCD camera (Image recognition 12) Inkjet head 13 Organic material 21 Display screen 23 Circle virtually created with the diameter of a straight line connecting two image recognition patterns

Claims (9)

[Claims] When an organic layer is formed by discharging a liquid-phase organic material onto pixels on a substrate by an ink-jet method, (a) an image recognition pattern is formed on the substrate in advance, and (b) the image recognition is performed. The position information of the substrate or the pixel is obtained by recognizing the pattern by the image recognition device. (C) Based on the position information of the substrate or the pixel, the ink jet head and the substrate or the pixel are aligned and the liquid organic material is removed. A method for manufacturing an organic electroluminescent display device, comprising controlling discharge timing. 2. The method according to claim 1, wherein the area recognizable by the image recognition device is in a pixel, and the image recognition pattern is formed in the pixel. 3. A method according to claim 1, wherein two or more image recognition patterns are formed on the substrate, and at least one of circles virtually created with all the straight lines connecting the two or more image recognition patterns as diameters. 2. The method according to claim 1, wherein the circle includes pixels from which liquid-phase organic material is discharged. 4. The at least one image recognition pattern,
4. The method according to claim 3, wherein the liquid organic material is formed in the pixel to be discharged. 5. The method according to claim 1, wherein the image recognition pattern is formed of an electrode material, an organic material, and / or an insulating material formed on the substrate. 6. The method according to claim 1, wherein the substrate is transparent or translucent, and the image recognition device recognizes the image recognition pattern through the substrate. 7. The apparatus according to claim 1, wherein the substrate is transparent or translucent, and the image recognition device recognizes the image recognition pattern through the substrate and also recognizes the position of the ink jet head.
A method according to any one of the preceding claims. 8. The method according to claim 1, wherein the liquid organic material is a coating liquid containing a polymer material. 9. The method according to claim 1, further comprising forming a partition layer thicker than the organic layer between pixels on the substrate in advance, and discharging an organic material into a region surrounded by the partition layer. A method according to any one of the preceding claims.