JP2004087509A - Organic electroluminescence device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make uniform the thickness of the organic EL film between the effective optical region picture elements and in each picture element. <P>SOLUTION: In the organic electroluminescent device that has a plurality of picture elements, the plural picture elements contain a plurality of display picture elements that are related to display and a plurality of dummy picture elements that are not related to display, and the electroluminescent device comprises an effective optical region where the display picture element is arranged and a dummy region which contains a plurality of dummy picture elements and is arranged outside of the above effective optical region. Each of the plural display picture elements and each of the plural dummy picture elements are divided by a partition wall, and an organic electroluminescent layer is formed in the region divided by the partition wall. <P>COPYRIGHT: (C)2004,JPO

Description

Related to organic electroluminescence (referred to as EL throughout this specification) devices and electronic equipment.

In recent years, development of light-emitting elements using organic substances has been accelerated as a spontaneous emission type display that replaces liquid crystal displays. As an organic electroluminescence element (referred to as EL throughout this specification) using an organic substance as a light emitting material, Appl. Phys. Lett. 51 (12), 21 September 1987, page 913, a method of forming a low molecular weight organic EL material (light emitting material) by vapor deposition, and Appl. Phys. Lett. 71 (1), 7 July 1997, page 34, a method of applying a polymer organic EL material is mainly reported.

As a means for colorization, in the case of a low molecular weight material, a method of depositing and forming a different light emitting material on a desired pixel through a mask is performed. On the other hand, coloration by fine patterning using an ink-jet method is attracting attention for polymer materials. The following known examples are known as the formation of an organic EL element by the ink jet method. JP-A-7-235378, JP-A-10-12377, JP-A-10-153967, JP-A-11-40358, JP-A-11-54270, JP-A-11-339957, and US006087196.

JP-A-7-235378 JP 10-12377 JP-A-10-153967 JP-A-11-40358 JP-A-11-54270 JP-A-11-339957 US Pat. No. 6,087,196 Appl. Phys. Lett. 51 (12), 21 September 1987, page 913- Appl. Phys. Lett. 71 (1), 7 July 1997, p. 34-

The ink jet method can discharge and apply droplets having a diameter of the order of μm with high resolution, and thus enables high-definition patterning of organic EL materials. However, the drying of the micro liquid applied on the substrate is very fast, and the solvent molecules evaporated from the micro liquid applied to the pixel area at the ends (upper end, lower end, right end, left end) of the application area on the substrate. Due to the low pressure, it generally begins to dry quickly. In addition, when active driving is performed using a TFT element, the pixel arrangement may not be equally spaced in the X and Y directions due to the shape and arrangement of the TFT element region, wiring, and the like. A local evaporation solvent molecular partial pressure difference occurs around the droplet. Such a difference in the drying time of the organic material liquid applied on the pixel causes unevenness of the film thickness of the organic thin film within the pixel and between the pixels. Such film thickness unevenness causes display unevenness such as luminance unevenness and emission color unevenness.

Accordingly, an object of the present invention is to provide an organic EL device manufactured by ejecting and applying an organic EL material on an electrode to form an organic EL layer, and surrounding the organic EL material solution applied to the pixel region. It is an object to provide a uniform organic EL device in which the environment and drying are made uniform, and there is no unevenness in luminance and emission color between and within each pixel in the effective optical region.

The present invention relates to a method for manufacturing an organic electroluminescence device in which an organic electroluminescence layer is formed on each electrode by applying a composition containing an organic electroluminescence material onto the plurality of electrodes, and is formed by the plurality of electrodes. The effective optical effective optical region is provided, and the application region of the composition containing the organic electroluminescent material is made larger than the effective optical region.

By the above manufacturing method, in the effective optical region, the environment and drying of the organic EL material liquid applied in the effective optical region can be made uniform, and the film thickness between and within each pixel can be made uniform. The organic electroluminescence layer refers to a layer that contributes to light emission, and includes a hole injection layer, a light emitting layer, an electron injection layer, and the like. The effective optical region indicates, for example, an effective optical region when the organic EL device is a display device, and a region that contributes to illumination when the organic EL device is a lighting device.

The method for manufacturing an organic EL device of the present invention is preferably characterized in that a coating region is also provided around the effective optical region.

With the above manufacturing method, it is possible to prevent the drying of the inner pixel droplets from becoming extremely faster than the inner pixel droplet drying in the effective optical region, and the film thickness between the effective optical pixels is uniform. Can be.

In the method of manufacturing the organic EL device according to the present invention, preferably, the application region provided around the effective optical region is a dummy region, and an organic EL material solution is applied to the dummy region to form an organic EL thin film layer. It is characterized by forming.

In addition, it is preferable to form a layer made of the same material as the electrode in the dummy region, and apply a composition containing the organic electroluminescent material on the layer.

By the above manufacturing method, the surrounding environment of the applied organic EL material liquid is made uniform even in the pixels at the end of the effective optical region, and the droplets in the pixel at the end of the effective optical region are dried. It is possible to prevent the organic EL thin film layer from becoming extremely faster than drying and to make the film thickness of the organic EL thin film layer uniform between the pixels in the effective optics.

Furthermore, in the method for manufacturing an organic EL device of the present invention, preferably, an effective optical region group including two or more effective optical regions is provided on a substrate, a dummy region is provided around each effective optical region, and Another dummy area is also provided around the effective optical area group.

Here, the dummy area is an area not related to display or illumination. Therefore, the organic EL layer formed in the dummy region may not emit light, but may emit light as long as it does not affect display and illumination.

According to the above manufacturing method, even when two or more effective optical regions are provided on one substrate and each effective optical region is separated in the final process to manufacture two or more organic EL devices, pixels at the end of the effective optical region The surrounding environment of the organic EL material liquid applied to the liquid crystal is made uniform in the same way as other pixels, and the drying of the inner pixel droplets is prevented from becoming extremely faster than the inner pixel droplet drying. And the film thickness of the organic EL thin film layer between the pixels can be made uniform. As a result, a plurality of organic EL devices having no unevenness in luminance and emission color can be manufactured at a time from one substrate between pixels and within each pixel.

In the method for producing an organic EL device according to the present invention, preferably, when the composition containing the organic electroluminescent material is applied, it is applied to the effective optical region after being applied to the dummy region at the start of application. At the end, it is characterized in that it is applied to the effective area and then applied to the dummy area.

According to the above manufacturing method, the application of the organic electroluminescence material solution starts from the dummy area and ends at the dummy area, so that the application in the effective optical area can be stably performed.

In addition, the method for manufacturing an organic EL device of the present invention is preferably characterized in that the individual application regions in the entire application region are equally spaced.

By the above manufacturing method, in the effective optical region, the environment and drying of the organic EL material liquid applied in the effective optical region are made uniform, and the film thickness of the organic EL thin film layer is uniform between and within each pixel. can do.

The organic EL device manufacturing method of the present invention is preferably characterized in that adjacent electrodes are arranged at equal intervals. By the above manufacturing method, in the effective optical region, the environment around the organic EL material liquid applied in the effective optical region, the drying is made uniform, and the film thickness of the organic EL thin film layer between the effective optical pixels and in each pixel is set. It can be made uniform.

The method for producing an organic EL device of the present invention is a method for producing an organic electroluminescence device having a plurality of electrodes and an effective optical region including an organic electroluminescence layer on each of the electrodes. The electroluminescence layer is formed in a region to be formed and outside a region to be the effective optical region.

Moreover, the manufacturing method of the organic EL device of the present invention is a manufacturing method of an organic electroluminescence device having a plurality of electrodes and an effective optical region including an organic electroluminescence layer on each of the electrodes. An organic electroluminescence layer is formed in a region where the electrode is not formed in a region to be formed.

Furthermore, according to the present invention, an organic EL device manufactured by the above method is provided. In such an organic EL device, uniform EL display without unevenness in luminance and emission color is achieved between pixels and within pixels in the effective optical region.

Next, the organic EL device of the present invention is preferably an organic electroluminescence device having a plurality of pixels, the plurality of pixels including a plurality of display pixels related to display and a plurality of dummy pixels not related to display. The electroluminescence device includes an effective optical region in which display pixels are disposed, and a dummy region that includes the plurality of dummy pixels and is disposed outside the effective optical region, and the plurality of display pixels. And each of the plurality of dummy pixels is partitioned by a partition, and an organic electroluminescence layer is formed in a region partitioned by the partition.
The partition includes an inorganic bank layer and an organic bank layer formed on the inorganic bank layer, and the organic electroluminescence layer is formed on the dummy electrode on the electrode provided in the pixel in the effective optical region. Each region is formed on a layer made of the same material as the inorganic bank layer.
A substrate and a circuit element portion provided on the substrate, and the organic electroluminescence layer is formed on the dummy region on the electrode formed on the circuit element portion in the effective optical region. Are respectively formed on the circuit element portion.
The organic electroluminescence layer is formed on the ITO in the effective optical region and the dummy region.
In addition, a cathode is formed on the electroluminescence layer in both the effective optical region and the dummy region.

Moreover, according to the present invention, an electronic apparatus comprising the above-described organic EL device is provided. According to such an electronic device, uniform EL display and illumination without unevenness in luminance and emission color between pixels and within pixels are realized.

As described above, according to the present invention, in the organic electroluminescence device having a plurality of pixels, the plurality of pixels includes a plurality of display pixels related to display and a plurality of dummy pixels not related to display, The electroluminescence device includes an effective optical region in which display pixels are disposed, and a dummy region that includes the plurality of dummy pixels and is disposed outside the effective optical region. Each of the plurality of dummy pixels is partitioned by a partition, and an organic electroluminescence layer is formed in a region partitioned by the partition, so that the organic EL formed in the pixel region Drying of the material solution is uniform, and there is no unevenness in brightness and emission color between pixels in the effective optical area or within each pixel. Display device, and it is possible to provide a display device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. An example in which an organic EL device is used as a display device is shown.

An organic EL device manufacturing method using an inkjet method is a method in which an ink composition in which a hole injection layer material composed of an organic material forming a pixel and a light emitting material are dissolved or dispersed in a solvent is ejected from an inkjet head onto a transparent electrode. In this method, patterning is applied to form a hole injection / transport layer and a light emitting layer. In order to pattern and apply the ejected ink droplets to a predetermined pixel area with high accuracy, it is usual to provide partition walls (hereinafter referred to as banks) that partition the pixel area.

FIG. 1 shows a cross-sectional view of an example of a substrate structure used for manufacturing an organic EL display by an ink jet method. A circuit element portion 11 ′ having a thin film transistor (TFT) 11 is formed on a glass substrate 10, and a transparent electrode 12 made of ITO is patterned on the circuit element portion 11 ′. Further, an SiO ₂ bank 13 and an organic bank 14 made of an ink-repellent or ink-repellent organic substance are laminated in a region partitioning the transparent electrode 12. The shape of the bank, that is, the opening shape of the pixel, may be any of a circle, an ellipse, and a square. The material of the organic bank 14 is not particularly limited as long as it has excellent heat resistance, liquid repellency, ink solvent resistance, and adhesion to the base substrate. Organic bank 14, the materials originally provided with liquid repellency, for example, be non-fluorine-based resins, usually used, an organic resin such as acrylic resin or polyimide resin is patterned, surface by CF ₄ plasma treatment May be made liquid repellent. The bank is not limited to the one in which the inorganic material and the organic material are laminated as described above. For example, when the transparent electrode 14 is made of ITO, the SiO ₂ bank 13 is used in order to improve the adhesion with the transparent electrode 14. Some are preferred. It is sufficient that the height of the organic bank 14 is about 1 to 2 μm.

Next, with reference to FIG. 2, an example of a method for manufacturing an organic EL device by an ink jet method will be described along the cross-sectional structure of each step.

In FIG. 2A, a solution (ink composition) containing an organic EL material is applied by patterning to a pixel substrate having a bank structure by an ink jet method to form an organic EL thin film. The organic EL material ink composition 15 is ejected from the inkjet head 16 and landed as shown in FIG. After coating, the solvent is removed by a flow of vacuum and / or heat treatment or nitrogen gas, and the organic EL thin film layer 17 is formed (FIG. 3C). The organic EL thin film layer 17 is a laminated film composed of, for example, a hole injection layer and a light emitting layer.

At this time, since ink droplets are not applied to the periphery of the display pixel at the end of the effective optical region (region where pixels related to display are formed), the solvent partial pressure of the ink solvent is lower than that on the inner pixel and the solvent is reduced. May dry quickly, and for example, a film thickness difference as shown in FIG. 2C may occur between display pixels.

Therefore, in order to uniformly dry the droplets applied to each pixel, the ink composition is discharged and applied around the effective optical region, and the same environment is applied to each droplet applied to the effective optical region. It is preferable to make. In order to construct a more same environment, the application area of the organic material by inkjet is made larger than the effective optical area. For example, a dummy area having a bank structure of the same shape as the display pixel around the effective optical area (not related to display) It is more preferable to install a region where dummy pixels are formed.

In order to make the drying of the ink composition between pixels in the effective optical area more uniform, it is desirable that the individual application areas in the effective optical area are equally spaced. For this purpose, the pixels are preferably arranged at equal intervals. In the case where the pixel intervals are designed differently in the X direction and the Y direction due to the installation of TFTs, wirings, etc., ink droplets may be ejected so that the intervals between the application regions are equal between the pixels with wider intervals. It is more preferable if a dummy pixel in which a bank structure having the same shape as the pixel portion is formed between the pixels. The shape of the pixel may not be a point-symmetric shape such as a circle or a square, but may be a rectangle, a track shape, or an ellipse. When pixels such as rectangles and track shapes are arranged at different intervals in the X direction and Y direction, the application regions have the same interval in a wide pixel interval even if they do not have the same shape as the pixel portion. Even if the coating region is formed so that

The present invention can be applied not only to display applications of organic EL devices, but also to light emitting devices and lighting devices that use organic EL elements as light emitting sources.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

The substrate used in this example is a 2-inch TFT substrate in which circular pixels with a diameter of 30 μm are arranged at a pitch of 70.5 μm in both the X and Y directions. The TFT substrate is composed of a glass substrate 25 and a circuit element portion 26 ′ having a TFT 26 formed on the glass substrate. FIG. 3A shows a partial cross-sectional view (X direction) of the right end side of the TFT substrate. A transparent electrode 27 made of ITO is formed on the circuit element portion 26 ′, and a two-layer bank of SiO ₂ bank 28 and polyimide bank 29 is formed on the circuit element portion 26 ′ so as to partition the transparent electrode 27. Yes. The SiO ₂ bank 28 is formed by patterning TEOS (tetraethylorthosilicate) with a thickness of 150 nm by CVD and by photoetching. Further, photosensitive polyimide is applied thereon, and a polyimide bank 29 having a thickness of 2 μm is formed by exposure and development. A non-photosensitive material may be used as a material for forming the bank.

In FIG. 3, the region where the transparent electrode 27 is formed is the effective optical region A, and the region where the transparent electrode 27 is not partitioned by the SiO ₂ bank 28 and the polyimide bank 29 is the dummy region B.

Prior to inkjet coating, the polyimide bank 29 is subjected to ink repellent treatment by atmospheric pressure plasma treatment. The atmospheric pressure plasma treatment is performed under atmospheric pressure at a power of 300 W, an electrode-substrate distance of 1 mm, an oxygen plasma treatment at an oxygen gas flow rate of 100 ml / min, a helium gas flow rate of 10 l / min, and a table transfer speed of 10 mm / s. Subsequently, the CF ₄ plasma treatment is performed by reciprocation of a CF ₄ gas flow rate of 100 ml / min, a helium gas flow rate of 10 l / min, and a table transfer speed of 3 mm / s.

Using Bayer (registered trademark) of Bayer as a hole injection layer material, an ink composition 30 dispersed with isopropyl alcohol, N-methylpyrrolidone, and 1,3-dimethyl-2-imidazolidinone as polar solvents was prepared. In the X and Y directions, the ink jet head (MJ-930C manufactured by Epson) is discharged and applied at a pitch of 70.5 μm. At that time, the upper and lower lines and the left and right lines are discharged around the display pixel at the same pitch. FIG. 3B shows a partial cross-sectional view on the right end side of the substrate after the hole injection layer material ink composition 30 has been pattern-coated. In the effective optical region A, the hole injection layer material ink composition 30 is applied on the transparent electrode 27, while in the dummy region B, the hole injection layer material ink composition 30 is applied on the polyimide bank 29.

Next, the solvent is removed in vacuum (1 torr (133.3 Pa)) at room temperature for 20 minutes, and then heat treatment is performed in nitrogen at 200 ° C. (on a hot plate) for 10 minutes in FIG. As shown, a hole injection layer 31 is formed. In the effective optical region A, the hole injection layer 31 having a uniform film thickness can be formed.

Next, using a polyfluorene-based material that emits red, green, and blue as the light emitting layer, the red light emitting layer ink composition 32, the green light emitting layer ink composition 33, and the blue light emitting layer ink composition 34 are obtained. Prepare 3 types. As the ink solvent, cyclohexylbenzene was used. As shown in FIG. 3C, these ink compositions 32, 33, and 34 were ejected from an ink jet head and applied in a pattern with a 211.5 μm pitch in the X direction and a 70.5 μm pitch in the Y direction. At this time, the upper and lower and left and right 21 lines are discharged to the dummy area B at an extra pitch.

Next, light emitting layers 35, 36, and 37 are formed by heat treatment at 80 ° C. for 5 minutes on a hot plate in an N ₂ atmosphere. In the effective optical region A, the light emitting layers 35, 36, and 37 having a uniform film thickness can be formed.

After forming the light emitting layer, as shown in FIG. 3D, as the cathode 38, a 2 nm LiF layer, a 20 nm Ca layer and a 200 nm Al layer are stacked by vacuum heating vapor deposition, and finally sealed with an epoxy resin 39. I do.

In this way, an organic EL device having a uniform display with no luminance unevenness and color unevenness in the effective optical region A could be obtained.

In the present embodiment, as shown in FIG. 4, a TFT substrate in which a dummy region B is arranged around the effective optical region A is used as in the first embodiment. The TFT substrate is composed of a glass substrate 25 and a circuit element portion 26 ′ having a TFT 26 formed on the glass substrate 25. Further, a transparent electrode 27 made of ITO is formed on the circuit element portion 26 ′, and a bank consisting of two layers of an SiO ₂ bank 28 and a polyimide bank 29 is formed on the circuit element portion 26 ′ so as to partition the transparent electrode 27. Has been. In this way, the display pixel 42 is formed in the effective optical area A.

In the dummy region B, a SiO ₂ film 28 ′ extending from the SiO ₂ bank is provided, and a dummy bank 40 is provided on the SiO ₂ film 28 ′ with the same shape and pitch as the display pixels 42. Pixels 43 are formed. FIG. 4A shows a partial cross-sectional view on the right end side of the substrate.

FIG. 4B shows a state where the hole injection layer ink composition 41 is applied by patterning to the display pixels 42 and the dummy pixels 43 at a pitch of 70.5 μm, as in Example 1. As in Example 1, the thickness of the hole injection layer of the display pixel 42 formed by drying and heat treatment was uniform.

Next, a light emitting layer ink composition made of a polyfluorene material is applied to the display pixels 42 and the dummy pixels 43 by patterning in the same manner as in Example 1, and the thickness of the light emitting layer formed by drying is uniform in the display pixels 42. there were. The organic EL device completed by forming and sealing the cathode had a uniform display with no luminance unevenness and color unevenness in the effective optical region A including the display pixels 42.

In this example, as in Example 1, a TFT substrate in which a dummy area B was disposed around the effective optical area A was used. As shown in FIG. 5A, the TFT substrate is composed of a glass substrate 25 and a circuit element portion 26 ′ having a TFT 26 formed on the glass substrate 25. Further, a transparent electrode 27 made of ITO is formed on the circuit element portion 26 ′, and a bank consisting of two layers of an SiO ₂ bank 28 and a polyimide bank 29 is formed on the circuit element portion 26 ′ so as to partition the transparent electrode 27. Has been. In this way, the display pixel 42 is formed in the effective optical area A.

Further, on the circuit element portion 26 ′ in the dummy region B, a dummy pixel 44 in which only the polyimide bank 29 is formed with the same shape and the same pitch as the display pixel 42 is provided. FIG. 5A is a partial cross-sectional view on the right end side of the substrate.

Next, as in Example 1, the polyimide bank 29 is subjected to ink repellent treatment by atmospheric pressure plasma treatment.

Next, as shown in FIG. 5B, in the same manner as in Example 1, the ink composition 30 containing the hole injection layer material was applied to the display pixel 42 and the dummy pixel 44 at a pitch of 70.5 μm in both the X and Y directions. Apply patterning to In the effective optical region A, the hole injection layer material ink composition 30 is applied on the transparent electrode 27, while in the dummy region B, the hole injection layer material ink composition 30 is applied on the circuit element portion 26 '. Yes.

Next, the solvent is removed under vacuum (1 torr (133.3 Pa)) at room temperature for 20 minutes, and then heat treatment is performed in nitrogen at 200 ° C. (on a hot plate) for 10 minutes to obtain FIG. A hole injection layer 31 as shown is formed. In the effective optical region A, the hole injection layer 31 having a uniform film thickness can be formed.

Next, as in Example 1, three types of red light emitting layer ink composition 32, green light emitting layer ink composition 33, and blue light emitting layer ink composition 34 were prepared, as shown in FIG. 5C. In addition, these ink compositions 32, 33, and 34 are ejected from an ink jet head, and are applied with a pattern at a pitch of 211.5 μm in the X direction and a pitch of 70.5 μm in the Y direction, respectively. At that time, it is preferable that the upper and lower and left and right 21 lines are discharged to the dummy area B at an extra pitch.

Next, the light emitting layers 35, 36 and 37 are formed by heat treatment at 80 ° C. for 5 minutes in a N ₂ atmosphere on a hot plate. In the effective optical region A, the light emitting layers 35, 36, and 37 having a uniform film thickness can be formed.

After the light emitting layer is formed, as shown in FIG. 5D, a 2 nm LiF layer, a 20 nm Ca layer and a 200 nm Al layer are stacked by vacuum heating deposition as the cathode 38 and finally sealed with an epoxy resin 39. I do.

Thus, it is possible to obtain an organic EL device having a uniform display in the effective optical region A with no luminance unevenness and color unevenness.

In this example, as in Example 1, a TFT substrate in which a dummy area B was disposed around the effective optical area A was used. As shown in FIG. 6A, the TFT substrate is composed of a glass substrate 25 and a circuit element portion 26 ′ having a TFT 26 formed on the glass substrate 25. Further, a transparent electrode 27 made of ITO is formed on the circuit element portion 26 ′, and a bank composed of two layers of an SiO ₂ bank 28 and a polyimide bank 29 is formed so as to partition the transparent electrode 27. In this way, the display pixel 42 is formed in the effective optical area A.

A dummy pixel 45 is provided on the circuit element portion 26 ′ in the dummy region B by laminating the SiO ₂ bank 28 and the polyimide bank 29 with the same shape and the same pitch as the display pixel 42. FIG. 6A is a partial cross-sectional view on the right end side of the substrate.

Next, as in Example 1, the polyimide bank 29 is subjected to ink repellent treatment by atmospheric pressure plasma treatment, and an ink composition 30 containing a hole injection layer material is further displayed on the display pixel 42 as shown in FIG. 6B. In addition, patterning is applied to the dummy pixels 45. In the effective optical region A, the hole injection layer material ink composition 30 is applied on the transparent electrode 27, while in the dummy region B, the hole injection layer material ink composition 30 is applied on the circuit element portion 26 '. .

Next, the solvent of the hole injection layer material ink composition 30 is removed under the same conditions as in Example 1, and further a heat treatment is performed under the same conditions as in Example 1, so that a hole injection layer 31 as shown in FIG. Form. In the effective optical region A, the hole injection layer 31 having a uniform film thickness can be formed.

Next, as in Example 1, a red light emitting layer ink composition 32, a green light emitting layer ink composition 33, and a blue light emitting layer ink composition 34 were prepared. As shown in FIG. Each ink composition 32, 33, 34 is ejected from an inkjet head to apply a pattern. At this time, the upper and lower and left and right 21 lines are discharged to the dummy area B at an extra pitch.

Next, the light emitting layers 35, 36 and 37 are formed by heat treatment at 80 ° C. for 5 minutes in a N ₂ atmosphere on a hot plate. In the effective optical region A, the light emitting layers 35, 36, and 37 having a uniform film thickness can be formed.

After forming the light emitting layer, as shown in FIG. 6D, a 2 nm LiF layer, a 20 nm Ca layer, and a 200 nm Al layer are stacked by vacuum heating deposition as the cathode 38, and finally sealed with an epoxy resin 39. I do.

Thus, it is possible to obtain an organic EL device having a uniform display in the effective optical region A with no luminance unevenness and color unevenness.

In this example, as in Example 1, a TFT substrate in which a dummy area B was disposed around the effective optical area A was used. As shown in FIG. 7A, the TFT substrate is composed of a glass substrate 25 and a circuit element portion 26 ′ having a TFT 26 formed on the glass substrate 25. Further, a transparent electrode 27 made of ITO is formed on the circuit element portion 26 ′, and a bank consisting of two layers of an SiO ₂ bank 28 and a polyimide bank 29 is formed on the circuit element portion 26 ′ so as to partition the transparent electrode 27. Has been. In this way, the display pixel 42 is formed in the effective optical area A.

A dummy pixel 46 is provided on the circuit element portion 26 ′ in the dummy region B by laminating the SiO ₂ bank 28 and the polyimide bank 29 with the same shape and the same pitch as the display pixel 42. Note that the TFT 26 is not provided in the circuit element portion 26 ′ in the dummy region B. FIG. 7A shows a partial cross-sectional view on the right end side of the substrate.

Next, in the same manner as in Example 1, the polyimide bank 29 is subjected to ink repellent treatment by atmospheric pressure plasma treatment, and an ink composition 30 containing a hole injection layer material is further displayed on the display pixel 42 as shown in FIG. In addition, patterning is applied to the dummy pixel 46. In the effective optical region A, the hole injection layer material ink composition 30 is applied on the transparent electrode 27, while in the dummy region B, the hole injection layer material ink composition 30 is applied on the circuit element portion 26 '. Yes.

Next, the solvent of the hole injection layer material ink composition 30 is removed under the same conditions as in Example 1, and further heat treatment is performed under the same conditions as in Example 1, so that a hole injection layer as shown in FIG. 31 is formed. In the effective optical region A, the hole injection layer 31 having a uniform film thickness can be formed.

Next, as in Example 1, a red light emitting layer ink composition 32, a green light emitting layer ink composition 33, and a blue light emitting layer ink composition 34 were prepared, and as shown in FIG. Each ink composition 32, 33, 34 is ejected from an inkjet head to apply a pattern. At that time, it is preferable that the upper and lower and left and right 21 lines are discharged to the dummy area B at an extra pitch.

Next, the light emitting layers 35, 36 and 37 are formed by heat treatment at 80 ° C. for 5 minutes in a N ₂ atmosphere on a hot plate. In the effective optical region A, the light emitting layers 35, 36, and 37 having a uniform film thickness can be formed.

After the light emitting layer is formed, as shown in FIG. 7D, a 2 nm LiF layer, a 20 nm Ca layer and a 200 nm Al layer are stacked by vacuum heating deposition as the cathode 38, and finally sealed with an epoxy resin 39. I do.

Thus, it is possible to obtain an organic EL device having a uniform display in the effective optical region A with no luminance unevenness and color unevenness.

The dummy pixel 46 is configured by providing the transparent electrode 27, the SiO ₂ bank 28 and the polyimide bank 29 that partition the transparent electrode 27, and is the same as the display pixel 42 except that the TFT 26 is not provided. Because of the configuration, the hole injection layer material ink composition 30 applied to the dummy pixel 46 can be dried under the same conditions as when applied to the display pixel 42, and thus the effective optical region A has a greater film thickness. A uniform hole injection layer 31 can be formed, and a uniform display organic EL device free from luminance unevenness and color unevenness can be obtained.

FIG. 8A shows part of the display pixel region and the dummy pixel region of the substrate used in this example. FIG. 8A is a plan view of the substrate, and the TFT element is not shown here. Circular pixels 50 having a diameter of 60 μm are arranged at a pitch of 80 μm in the horizontal (X) direction and at a pitch of 240 μm in the vertical (Y) direction. There is a dummy bank pixel 51 having a diameter of 80 μm and a diameter of 60 μm between the display pixels in the vertical direction line. Around the effective optical region, dummy pixels 52 having the same shape are vertically, right and left, 30 lines, and the same pitch of 80 μm. It is formed with. The display pixels are divided by the stacked banks of the SiO ₂ bank 53 and the polyimide bank 54 as before, and the basic cross-sectional structure other than the pixel diameter and pitch is the same as in the first or second embodiment.

FIG. 8B shows a state in which the same hole injection layer material ink composition 55 as that in Example 1 was applied to the display pixels 50 and the dummy pixels 51 and 52 in a pattern with a pitch of 80 μm. In the same manner as in Example 1, a hole injection layer was formed, and in the light emitting layer, the same three types of light emitting layer compositions 56, 57, and 58 as in Example 1 were applied in a pattern with a vertical pitch of 80 μm and a horizontal pitch of 240 μm, A light emitting layer was laminated and formed by drying. FIG. 8C shows the pattern application of the light emitting layer ink composition. The organic EL device completed by forming and sealing the cathode had a uniform display with no luminance unevenness and color unevenness in the effective optical region.

FIG. 9A shows part of the effective optical region and the dummy region of the substrate used in this example. FIG. 9A is a plan view of the substrate, and the TFT element is not shown here. Rectangular (rounded corners) -shaped pixels 60 having a width of 50 μm and a length of 200 μm are arranged at a pitch of 80 μm in the horizontal (X) direction and at a pitch of 290 μm in the vertical (Y) direction. The interpixel spacing in the horizontal direction is 30 μm, and the interpixel spacing in the vertical direction is 90 μm. Around the display pixels 60..., Dummy pixels 61 having the same shape are formed at the same pitch of 80 μm and 290 μm for up and down, left and right, and 30 lines. The display pixel 60 is partitioned by a stacked bank of SiO ₂ 62 and polyimide 63 as before, and the basic cross-sectional structure other than the pixel diameter and pitch is the same as in the first or second embodiment.

The hole injection layer material ink composition 64 similar to that in Example 1 was applied to all the display pixels 60 and dummy pixels 61 in a pattern, and the composition was also applied to the center between the pixels in the vertical direction as shown in FIG. 9B. 64 was applied in a pattern. After drying, the hole injection layer in the formed pixel showed a uniform film thickness, but if it was not applied at the center between the pixels in the vertical direction, the film thickness was extremely thick at both ends in the vertical direction of the pixel. It got thick.

After forming the hole injection layer, the same light emitting layer composition 65, 66, and 67 as in Example 1 was applied to the light emitting layer by pattern coating at pitches of 240 μm and 290 μm, respectively. Similarly to the case, the light emitting layer ink compositions 65, 66, and 67 were also applied in a pattern at the center between the pixels in the vertical direction as shown in FIG. 9C. As a result, the thickness of the dried light emitting layer was uniform within and between pixels. The organic EL device completed by forming and sealing the cathode had a uniform display with no luminance unevenness and color unevenness in the effective optical region.

FIG. 10A shows a plan view of a substrate used in this example. FIG. 10B is a partial cross-sectional view taken along line MM ′ of FIG. As shown in FIGS. 10A and 10B, this substrate 101 is a substrate before the formation of the hole injection layer and the light emitting layer, and the circuit element portion 103 formed on the glass substrate 102; The light emitting element unit 104 is formed on the circuit element unit 103. The light emitting element section 104 is provided with display pixels and dummy pixels, which will be described later, and the light emitting element section 104 further includes an effective optical area A composed of display pixel groups and a dummy disposed around the effective optical area A. It is partitioned into a dummy area B consisting of a pixel group.

The circuit element unit 103 includes a plurality of TFT elements 105 formed on the glass substrate 102 and first and second interlayer insulating films 106 and 107 covering the TFT elements 105. The TFT elements 105 are arranged in a matrix, and transparent electrodes 108 made of ITO are connected to the TFT elements 105.
The transparent electrodes 108 are formed on the second interlayer insulating film 107 and are disposed at positions corresponding to the TFT elements 105. The transparent electrode 108 only needs to be formed in a shape such as a substantially circular shape, a rectangular shape, or a rectangular shape having a square arc shape in plan view.

The TFT element 105 and the transparent electrode 108 are formed only at positions corresponding to the effective optical region A of the light emitting element unit 104.

Next, the SiO ₂ bank 109 and the polyimide bank 110 are laminated in the effective optical region A of the light emitting element portion 104. The SiO ₂ bank 109 and the polyimide bank 110 are provided between the transparent electrodes 108. Thereby, an opening 111 surrounding the transparent electrode 108 is provided.

In addition, the dummy region B of the light emitting element portion 104 is provided with a SiO ₂ thin film 109 ′ formed on the second interlayer insulating film 107 and a polyimide bank 110 ′ formed on the SiO ₂ thin film 109 ′. Yes. A dummy pixel 111 ′ having substantially the same shape as the display pixel 111 in the display pixel region A is provided by the polyimide bank 110 ′ in the dummy region B.

Regarding the number of dummy pixels 111 ′ provided in the dummy region B, there are 10 or more sets of three dummy pixels of R, G, and B between the width X ′ along the X direction shown in FIG. It is preferable to provide it. Further, it is preferable to provide 10 or more columns of a large number of R, G, and B dummy pixels between the widths Y ′ along the Y direction shown in FIG. More preferably, the dummy pixels are arranged so that the width X ′ and the width Y ′ are equal. By doing so, the drying condition of the composition ink in the pixels near the boundary with the dummy area B can be made more consistent with the drying conditions in the pixels near the center of the effective optical area A. In order to make the width X ′ and the width Y ′ equal, for example, each pixel (both display pixel and dummy pixel) is arranged at a pitch of 70.5 μm in the X direction and a pitch of 211.5 μm in the Y direction. When formed, 30 lines parallel to the Y direction between the width X ′ (lines consisting of three pairs of three dummy pixels R, G, B) and X between the width Y ′ A dummy pixel having 10 lines parallel to the direction may be formed. Accordingly, since the pitch in the Y direction is three times the pitch in the X direction, the widths X ′ and Y ′ are substantially equal. The number of dummy pixels is not limited to this, but if the number of dummy pixels 111 ′ is excessive, the frame not related to display becomes large, that is, the display module becomes large, which is not preferable.

The substrate 101 is subjected to atmospheric pressure plasma processing as in Example 1 to perform ink repellent treatment on the polyimide banks 110 and 110 ′, and an ink composition containing a hole injection layer material is ejected from the inkjet head for display. Patterning is applied to the pixel 111 and the dummy pixel 111 ′. In the display pixel 111, the hole injection layer material ink composition is applied on the transparent electrode 108, while in the dummy 111 ′, the hole injection layer material ink composition is applied on the SiO ₂ thin film 109 ′.

When the ink composition containing the hole injection layer material is ejected by the ink jet head, for example, an ink jet head having a nozzle row having a width approximately equal to the width direction (X direction in the drawing) of the display element unit 104 is prepared. It is preferable to carry out the inkjet head while moving it on the substrate 101 along the arrow Y direction in the figure from the lower side of FIG. As a result, the ejection order of the ink composition is in the order of the lower dummy area B in the figure, the effective optical area A, and the upper dummy area B in the figure, and the ink composition is ejected from the dummy area B to the dummy area. You can end with B. Since the composition ink is ejected in the dummy area B and then ejected in the effective optical area A, the ink composition in the effective optical area A can be uniformly dried.

Next, the solvent of the hole injection layer material ink composition is removed under the same conditions as in Example 1, and heat treatment is further performed under the same conditions as in Example 1 to form a hole injection layer 131 as shown in FIG. Form.

A dummy pixel 111 ′ is provided outside the effective optical region A, and the composition ink is discharged and dried in the same manner as the display pixel 111 on the dummy pixel 111 ′. The drying conditions of the composition ink in the display pixels 111 in the vicinity can be made to substantially coincide with the drying conditions in the display pixels 111 in the vicinity of the center of the effective optical area A, and thereby the display pixels in the vicinity of the boundary with the dummy area B 111 can form the hole injection layer 131 having a uniform film thickness. Therefore, the hole injection layer 131 having a uniform film thickness can be formed over the entire effective optical region A.

Next, in the same manner as in Example 1, the red, green, and blue light emitting layer ink compositions were ejected from the inkjet head and applied to the display pixels 111 and the dummy pixels 111 ′, and the N ₂ atmosphere was applied on the hot plate. The light emitting layers 135, 136, and 137 are formed by heat treatment at 80 ° C. for 5 minutes. In the effective optical region A, the light emitting layers 135, 136, and 137 having a uniform film thickness can be formed in the same manner as in the case of the hole injection layer 131.

In the formation of the light emitting layer, the inkjet head is moved from the lower side of FIG. 10A onto the substrate 101 along the arrow Y direction in the same manner as in the case of the hole injection layer. The ink composition is discharged in the order of the lower dummy area B in the figure, the effective optical area A, and the upper dummy area B in the figure, whereby the ink composition is discharged from the dummy area B in the dummy area B. It is preferable to end the process. Thereby, in the whole effective optical area A, the ink composition containing a light emitting layer was able to be dried uniformly.

After the light emitting layer is formed, as shown in FIG. 11B, a 2 nm LiF layer, a 20 nm Ca layer and a 200 nm Al layer are stacked by vacuum heating deposition as a cathode 138, and finally sealed with an epoxy resin 139. I do.

Thus, it is possible to obtain an organic EL device having a uniform display in the effective optical region A with no luminance unevenness and color unevenness.

FIG. 12 shows a plan view of the substrate used in this example. As shown in FIG. 12, the substrate 201 is mainly composed of a circuit element portion (not shown) formed on the glass substrate 202 and a plurality of light emitting element portions 204... Formed on the circuit element portion. ing. On the substrate 201 of FIG. 12, 16 light emitting element portions 204 are arranged in a matrix of 4 columns and 4 rows. Each light emitting element portion 204 is provided with display pixels and dummy pixels not shown in the same manner as in the eighth embodiment, and each light emitting element portion 204... Has an effective optical region A composed of display pixel groups, and effective optical elements. The area is divided into a dummy area B including dummy pixel groups arranged around the area A.

The configurations of the display pixels in the effective optical region A and the dummy pixels in the dummy region B are the same as the configurations of the display pixel 111 and the dummy pixel 111 ′ described in the eighth embodiment. The configuration of the circuit element unit (not shown) is the same as the configuration of the circuit element unit 103 of the eighth embodiment.

In this way, the substrate 201 is formed with an effective optical region group C composed of a plurality of effective optical regions A.

The substrate 201 is finally cut along a one-dot chain line in the figure and cut into 16 small substrates. Thereby, a plurality of organic EL devices can be manufactured simultaneously from one substrate.

Furthermore, another dummy region D is formed around the effective optical region group C on the substrate 201.

As for the number of dummy pixels provided in the dummy region D, it is preferable to provide 10 or more sets of three dummy pixels of R, G, and B between the width X ′ along the X direction shown in FIG. Further, it is preferable to provide 10 or more columns of a large number of R, G, and B dummy pixels between the width Y ′ along the Y direction shown in FIG.

The substrate 201 is subjected to ink repellent treatment in the same manner as in Example 8, and an ink composition containing a hole injection layer material is ejected from an inkjet head and applied to display pixels and dummy pixels by patterning.

When the ink composition containing the hole injection layer material is ejected by the ink jet head, for example, an ink jet head having a nozzle row having the same width as one display element portion 204 in the width direction (X direction in the drawing) is used. It is preferable that the inkjet head is prepared and moved while moving from the lower side in the drawing of FIG. 12 to the upper side in the drawing along the arrow Y direction in the drawing. The width of the inkjet head is not limited to this, and may be an integer multiple of the width of one display element unit 204.

The locus of the inkjet head at this time is a zigzag locus in which, for example, as shown in FIG. 13 (A), the inkjet head H is moved to the upper side in the drawing and then runs obliquely to the lower side and then moved upward again. Alternatively, as shown in FIG. 13B, it may be a folded trajectory that moves upward, then slides (runs idle) in the horizontal direction, and then moves downward.

In any of the above cases, the ejection order of the ink composition is dummy areas D and B, effective optical area A, dummy areas B and D, dummy areas D and B, effective optical areas A,..., Dummy areas B and D In this order, the ejection of the ink composition can be started from the dummy area D and ended in the dummy area D.

Further, as in Example 8, an ink jet head having a nozzle row having a width approximately the same as the width direction (X direction in the drawing) of the effective optical region group C is prepared, and this ink jet head is arranged on the lower side in FIG. The display element unit 204 may be moved to the upper side in the figure along the arrow Y direction in the figure. In this case, the ejection order of the ink composition is the order of the dummy areas D and B, the effective optical area A, and the dummy areas B and D. The ejection of the ink composition starts from the dummy area D and ends in the dummy area D. Can do.

Therefore, in any case, since the ink composition is discharged from the dummy area D and then discharged from the effective optical area A, the ink composition can be uniformly dried in the entire effective optical area A.

In addition, when the inkjet head takes a zigzag trajectory or a zigzag trajectory, the ink is always discharged from the dummy area D after the idle run, so the state of the ink filled in the inkjet head changes during the idle run. Even in this case, preliminary ejection is performed in the dummy area D and then ejection is performed in the effective optical area A, and ejection in the effective optical area A can be performed stably.

Next, the solvent of the hole injection layer material ink composition is removed and heat treatment is performed in the same manner as in Example 1 to form the hole injection layer 131.

Since the dummy pixels of the dummy area B are provided outside the effective optical area A and the dummy pixels of another dummy area D are further provided outside the effective optical area A, the display pixels in the vicinity of the boundary with the dummy area B The drying conditions of the composition ink can be made to substantially coincide with the drying conditions of the display pixels near the center of the effective optical region A, so that even a display pixel near the boundary with the dummy region B has a uniform thickness. An injection layer can be formed. Therefore, a hole injection layer having a uniform film thickness can be formed over the entire effective optical region A.

Particularly, since the dummy region D is provided around the effective optical region group C, a hole injection layer having a uniform thickness can be formed even when a large number of display devices are manufactured from one substrate.

Next, in the same manner as in Example 1, the red, green, and blue light emitting layer ink compositions were ejected from the ink jet head, applied to the effective optical region and the dummy region, and then subjected to heat treatment to obtain R, G, and B A light emitting layer is formed. In the effective optical region A, a light emitting layer having a uniform thickness can be formed as in the case of the hole injection layer.

When forming the light emitting layer, the ink jet head is moved as shown in FIG. 13 (A) or FIG. 13 (B) in the same manner as in the case of the hole injection layer. The ejection order is the same as that in the case of the hole injection layer, whereby the ejection of the ink composition can be started from the dummy area D and ended in the dummy area D.
As a result, the ink composition could be uniformly dried over the entire effective optical area A.

After forming the light emitting layer, a 2 nm LiF layer, a 20 nm Ca layer, and a 200 nm Al layer are stacked by vacuum heating deposition as a cathode, and finally sealed with an epoxy resin.

Thus, it is possible to obtain an organic EL device having a uniform display in the effective optical region A with no luminance unevenness and color unevenness.

In addition, although the high molecular material was used here as an organic EL layer, you may use a low molecular material. When a low molecular material is used, it is preferably formed by an evaporation method using a mask 71 as shown in FIG. At this time, the present invention can be realized by depositing a material using a mask in which an area corresponding to the effective optical area E and an area outside the area corresponding to the effective optical area E (area corresponding to the dummy area F) are opened. . Even when the vapor deposition method is used, it is possible to form a uniform organic EL layer in the entire effective optical region by providing the dummy region.

Next, a specific example of an electronic device including any one of the organic EL devices manufactured according to the first to ninth embodiments will be described.

FIG. 15A is a perspective view showing an example of a mobile phone. In FIG. 15A, reference numeral 600 denotes a mobile phone body, and reference numeral 601 denotes a display portion using any of the organic EL devices.

FIG. 15B is a perspective view showing an example of a portable information processing apparatus such as a word processor or a personal computer. In FIG. 15B, reference numeral 700 denotes an information processing apparatus, reference numeral 701 denotes an input unit such as a keyboard, reference numeral 703 denotes an information processing apparatus body, and reference numeral 702 denotes a display unit using any one of the organic EL devices. Yes.

FIG. 15C is a perspective view showing an example of a wristwatch type electronic device. In FIG. 15C, reference numeral 800 denotes a watch body, and reference numeral 801 denotes a display unit using any of the organic EL devices.

Each of the electronic devices shown in FIGS. 15A to 15C includes a display unit using any one of the above-described organic EL devices, and the organic EL device manufactured in the previous Examples 1 to 9 Therefore, an electronic device having an effect of excellent display quality can be obtained regardless of which organic EL device is used.

Sectional drawing which shows an example of the manufacturing method of the organic electroluminescent apparatus by an inkjet system. Sectional drawing which shows an example of the manufacturing method of the organic electroluminescent apparatus by the inkjet system in connection with this invention. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 1. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 2. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 3. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 4. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 5. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 6. FIG. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 7. FIG. It is a figure explaining the manufacturing method of the organic electroluminescent apparatus of Example 8, Comprising: (A) is a top view of the board | substrate before hole injection layer formation, (B) is the part which followed the MM 'line | wire of (A). It is sectional drawing. Process drawing explaining the manufacturing method of the organic electroluminescent apparatus of Example 8. FIG. It is a figure explaining the manufacturing method of the organic electroluminescent apparatus of Example 9, Comprising: It is a top view of the board | substrate before hole injection layer formation. It is a figure explaining the manufacturing method of the organic electroluminescent apparatus of Example 9, Comprising: It is a schematic diagram which shows the locus | trajectory of an inkjet head. It is a figure explaining the other manufacturing method of the organic electroluminescent apparatus of Example 9. FIG. FIG. 16 is a perspective view showing an electronic apparatus of Example 10.

Explanation of symbols

10, 25, 102, 202 Glass substrate 11 Thin film transistor (TFT)
12, 27, 108 Transparent electrodes 13, 28, 53, 62, 109 SiO ₂ banks 14, 29, 40, 54, 63, 110, 110 ′ Organic matter (polyimide) bank 15 Organic EL material Ink composition 16 Inkjet head 17 Organic EL thin film layer 17 Light emitting layer ink composition 26 Thin film transistor (TFT)
30, 41, 55, 64 Hole injection layer material ink composition 31 Hole injection layer 32, 56, 65 Red light emitting material ink composition 33, 57, 66 Green light emitting material ink composition 34, 58, 67 Blue light emitting material Ink composition 35 Red light emitting layer 36 Green light emitting layer 37 Blue light emitting layer 38 Cathode 42 Display pixel 43, 44 Dummy pixel 50 Display pixel 51 Dummy pixel in display pixel region 52 Dummy pixel outside display pixel region 60 Display pixel 61 Outside display pixel region Dummy pixel 101, 201 Substrate 103 Circuit element part 104, 204 Display element part 105 TFT element 109 'SiO ₂ thin film 111 Display pixel 111' dummy pixel 131 Hole injection layer 135, 136, 137 Light emitting layer A Effective optical area B, D Dummy area C Effective optical area group

Claims (6)

In the organic electroluminescence device having a plurality of pixels, the plurality of pixels include a plurality of display pixels related to display and a plurality of dummy pixels not related to display, and the electroluminescence device includes display pixels. An effective optical region, and a dummy region including the plurality of dummy pixels and disposed outside the effective optical region, and each of the plurality of display pixels and each of the plurality of dummy pixels is a partition wall. An organic electroluminescence device, wherein an organic electroluminescence layer is formed in a region partitioned by the partition wall. 2. The organic electroluminescent device according to claim 1, wherein the partition includes an inorganic bank layer and an organic bank layer formed on the inorganic bank layer, and the organic electroluminescent layer is a pixel in the effective optical region. An organic electroluminescent device, wherein the dummy region is formed on a layer made of the same material as the inorganic bank layer in the dummy region. The organic electroluminescence device according to claim 1, further comprising: a substrate; and a circuit element unit provided on the substrate, wherein the organic electroluminescence layer is disposed on the circuit element unit in the effective optical region. An organic electroluminescence device, wherein the dummy region is formed on the circuit element portion in the dummy region. 2. The organic electroluminescence device according to claim 1, wherein the organic electroluminescence layer is formed on the ITO in the effective optical region and the dummy region. 6. The organic electroluminescence device according to claim 1, wherein a cathode is formed on the electroluminescence layer in both the effective optical region and the dummy region. apparatus. An electronic apparatus comprising the organic electroluminescence device according to any one of claims 1 to 6.

Images