JP2001022297A - Display device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to form fine barriers for separating the pixel regions disposed on transparent conductive films by electrodeposition coating with an inexpensive device. SOLUTION: The transparent conductive films 3 are formed like stripes in the prescribed direction on a glass substrate 2 and are provided thereon with the barriers 4 apart prescribed spacings. Organic electric field elements 5 are formed in the pixel regions separated by these barriers 4. The formation of the barriers 4 is executed by first applying and forming resist films on the transparent conductive film 3 and removing the resist films of the portions where the patterns corresponding to the barriers 4 are opened by irradiation with UV rays. When the glass substrate 2 is immersed into a solution containing an electrodeposition resin and voltage is impressed between the electrodes disposed in the solution and the transparent conductive films 3, the electrodeposition resin moves near to the transparent conductive films 3 and gradually condenses. The films of the electrodeposition resin are thus formed on the transparent conductive films 3. The resist films exclusive of the films of the electrodeposition resin are removed, by which the barriers 4 consisting of the electrodeposition resin are completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device and a method of manufacturing the same, and more particularly, to a display device in which an organic electroluminescent device is formed in a pixel region separated by a partition, and the organic electroluminescent device is used as a pixel, and a method of manufacturing the same. About the method.

[0002]

2. Description of the Related Art A display device using an organic electroluminescent device (hereinafter, referred to as an EL device) as a light emitting material is known. An EL element is composed of a thin film mainly composed of a fluorescent organic compound. This thin film is sandwiched between an anode and a cathode, and electrons and holes are injected into the thin film and recombined to generate excitons (exington). It is a device that emits light using light emitted when the exxin is deactivated.

A display device using this EL element is, specifically, a transparent conductive film (anode) formed on a glass substrate and formed on the transparent conductive film to separate each pixel region. The EL element is formed in a pixel region separated by the partition on the transparent conductive film.

[0004] The partition is formed by forming a pattern as a base of the partition using photolithography, and then forming a partition material film on the pattern by sputtering or vapor deposition. The partition has a function as a black matrix for improving the contrast of an image as well as a function for separating a pixel region.

A display device using the above-described EL element can be driven at a low voltage of about 10 V.
Further, since it does not require a light source such as a backlight, it has an advantage that it can be formed extremely thin, and is expected to be applied as an ultra-thin display device for a computer or a portable information terminal device. .

[0006]

In a display device using an EL element, it is necessary to miniaturize pixels in order to increase the resolution of a screen. Furthermore, in order to realize the miniaturization of pixels, it is necessary to form partition walls finely. However, in the conventional method using a sputtering method or a vapor deposition method, the partition wall size is reduced from a technical viewpoint and a manufacturing cost viewpoint. Had limitations.

The present invention has been made in view of the above-mentioned problems, and does not require a device that requires a high vacuum, such as a sputtering device or a vapor deposition device. Further, an object of the present invention is to provide a display device capable of forming fine partition walls at low cost and a method for manufacturing the same.

[0008]

In order to achieve the above-mentioned object, a display device according to the present invention comprises a transparent conductive film formed on a substrate in stripes in a predetermined direction; A partition separating a plurality of pixel regions provided at predetermined intervals on the upper side, and an organic electroluminescent element formed in the pixel region is provided, wherein the partition is formed by electrodeposition coating. . This partition is preferably formed mainly of a cationic electrodeposition resin. Preferably, a black material is dispersed in the cationic electrodeposition resin to make the partition walls black.

Further, according to a method of manufacturing a display device according to the present invention, a transparent conductive film formed on a substrate in a stripe shape in a predetermined direction and a predetermined interval provided on the transparent conductive film are provided. Forming a transparent conductive film on a substrate, comprising: a partition that separates a plurality of pixel regions; and an organic electroluminescent element formed in the pixel region. Applying a resist film to the resist film, irradiating a predetermined region of the resist film with ultraviolet light, developing the resist film, and immersing the substrate in a solution containing an electrodeposition resin. Applying a voltage between the transparent conductive film and the transparent conductive film to deposit an electrodeposition resin on the transparent conductive film to form a partition. As the electrodeposition resin, a cationic electrodeposition resin is preferably used.

According to the display device and the method of manufacturing the same according to the present invention, since the partition walls are formed by electrodeposition coating,
Fine partition walls are produced at low cost. When a cationic electrodeposition resin is used as the electrodeposition resin, elution of the transparent conductive film can be reduced during electrodeposition. Further, when a black material is dispersed in the cationic electrodeposition resin to make the partition walls black, the contrast of the display device screen is improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a display device and a method of manufacturing the same according to the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, a display device 1 according to an embodiment of the present invention has a glass substrate 2 and a transparent conductive film 3 formed on the glass substrate 2 in stripes in a predetermined direction.
A partition 4 provided on the transparent conductive film 3 at predetermined intervals to separate a plurality of pixel regions; and a plurality of organic electric field elements (hereinafter referred to as EL) formed in the pixel regions separated by the partition. 5).

The plurality of EL elements 5 correspond to red, blue, and green pixels, respectively, and emit light according to a structure described later. Various images are displayed on the screen on the opposite side.

As shown in FIG. 2, the EL element 5 includes a hole injection layer 6, a hole transport layer 7, a light emitting layer 8, and an electron transport layer 9 which are sequentially formed on the transparent conductive film 3. Be composed. A cathode electrode 10 is provided on the electron transport layer 9,
By applying a voltage of about 10 V between the cathode electrode 10 and the transparent conductive film 3 serving as an anode, holes injected from the transparent conductive film 3 side and holes injected from the cathode electrode 10 side are applied. The electrons recombine in the light emitting layer 8 made of an organic phosphor, thereby generating excitons. This exciton emits light in the process of being deactivated, and this light is radiated outside through the transparent conductive film 3 and the glass substrate 2.

The light emitting layer 8 can be made of a conventionally used material. Such materials include, for example, distyrylarylene (DSA) -based materials, oxadiazole-based materials, pyrazoloquinoline-based materials, bezooxazole-based materials, benzothiazole-based materials, benzimidazole-based materials, and metal chelate compounds. Can be mentioned. Further, by selecting the type of this material, light emission from blue to red is possible.

The partition 4 has a function of separating the EL elements 5 from each other, and also has a function as a black matrix. That is, the partition wall 4 is formed of a black substance, and functions to improve contrast of an image displayed on a screen by absorbing light incident from the outside via the glass substrate 2 and the transparent conductive film 3. have.

Here, a method of forming the partition 4 will be described.

First, as shown in FIG. 3A, a transparent conductive film 3 made of, for example, indium oxide or tin oxide is formed on a glass substrate 2.

Next, as shown in FIG. 3B, a resist film 11 is formed on the transparent conductive film 3 by coating.

Next, as shown in FIG. 3C, the resist film 11 is irradiated with ultraviolet rays through a mask 12 in which a pattern corresponding to the partition 4 is opened.

Next, as shown in FIG. 3D, a developing process is performed to remove the resist film 11 in the portion irradiated with the ultraviolet rays in the above-mentioned step, that is, the portion corresponding to the partition wall 4. In this specific example, a positive resist is used as the resist film 11, but a negative resist may be used here. In this case, a pattern opposite to this specific example is opened in the mask 12, and in the developing process,
The portions not irradiated with the ultraviolet rays are removed while leaving the portions irradiated with the ultraviolet rays.

Next, as shown in FIG. 4E, the glass substrate 2 is immersed in a solution 13 containing an electrodeposition resin such as a positively charged cationic electrodeposition resin.
A voltage is applied between the electrode 14 provided inside 3 and the transparent conductive film 3. Here, the cationic electrodeposition resin is selected as a preferable material for reducing the elution of the transparent conductive film 3 into the liquid at the time of electrodeposition. As a result, the electrodeposition resin moves to the vicinity of the transparent conductive film 3, and gradually condenses to form an electrodeposition resin film on the transparent conductive film 2. The electrodeposited resin itself does not have conductivity, and therefore, the portion where the conductive resin film is formed loses conductivity, so that when a certain film thickness is formed, the film deposition is completed, Film deposition does not proceed any further.

Next, as shown in FIG. 4F, the resist film 11 is removed while leaving the electrodeposited resin film formed on the transparent conductive film 3 as described above. Thus, the partition 4 made of the electrodeposited resin is completed.

Subsequently, the partition walls 4 formed as described above are formed.
For the region on the transparent conductive film 3 separated by the above, that is, the pixel region, using a well-known method such as a vapor deposition method, for example, the hole injection layer 6, the hole transport layer 7, and the light emission as shown in FIG. The layer 8, the electron transport layer 9, and the cathode electrode 10 are sequentially formed. Further, in order to protect the EL element 5 thus formed from mechanical shock and to prevent deterioration of the EL element, a protective film may be formed or a protective substrate may be provided as necessary. You may.

By forming the barrier ribs 4 by electrodeposition coating in this way, the thickness of the barrier ribs 4 can be easily controlled and fine barrier ribs 4 can be formed at low cost.
Further, by finely forming the partition 4, the EL element 5 formed in the pixel region defined by the partition 4 can be miniaturized, and thus a display device with high resolution can be provided.

In addition, by dispersing a black substance in the above-mentioned cation-based resin and making the above-mentioned partition walls 4 black, a better contrast of an image in a display device can be obtained.

In the display device according to the present invention, the partition for separating the pixel region is formed by electrodeposition coating.
Fine partition walls can be formed at low cost, and thus a high-resolution display device can be provided at low cost. Further, when a cationic resin is used as the electrodeposition resin, elution of the transparent electrode into the liquid during electrodeposition can be reduced. Further, when a black substance is dispersed in the cationic electrodeposition resin, a better contrast of the display device image can be obtained.

In the method of manufacturing a display device according to the present invention, a resist film is applied on a transparent conductive film formed on a substrate, and a predetermined region of the resist film is irradiated with ultraviolet rays to perform a developing process. After performing, the substrate is immersed in a solution containing the electrodeposited resin, a voltage is applied between the solution and the transparent conductive film, and the electrodeposited resin is deposited on an exposed portion of the transparent conductive film to form a partition. Form. By forming the partition walls by electrodeposition coating, fine partition walls having a uniform film thickness can be formed at low cost, and thus a high-resolution display device can be provided at low cost.

[0028]

[Brief description of the drawings]

FIG. 1 is a diagram showing a display device to which the present invention is applied.

FIG. 2 is a cross-sectional view of a pixel region of the display device shown in FIG.

FIG. 3 is a diagram illustrating a process of forming a partition.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display apparatus 2 Glass substrate 3 Transparent conductive film 4 Partition wall 5 EL element

Claims (6)

[Claims] A transparent conductive film formed in stripes in a predetermined direction on a substrate; a partition separating a plurality of pixel regions provided at predetermined intervals on the transparent conductive film; The display device, comprising: an organic electroluminescent element formed in the pixel region; wherein the partition is formed by electrodeposition coating. 2. The display device according to claim 1, wherein a material of the partition wall is mainly composed of a cationic electrodeposition resin. 3. The display device according to claim 2, wherein the partition walls are made black by dispersing a black substance in the cationic electrodeposition resin. 4. A transparent conductive film formed in stripes in a predetermined direction on a substrate, and a partition separating a plurality of pixel regions provided at predetermined intervals on these transparent conductive films, A method for manufacturing a display device comprising: an organic electroluminescent element formed in the pixel region; a step of forming a transparent conductive film on a substrate; and a step of applying a resist film on the transparent conductive film. Irradiating a predetermined region of the resist film with ultraviolet light; developing the resist film; immersing the substrate in a solution containing an electrodeposition resin; Applying a voltage to the transparent conductive film to deposit the electrodeposited resin on the transparent conductive film to form a partition wall. 5. The method according to claim 4, wherein the electrodeposition resin is mainly composed of a cationic electrodeposition resin. 6. The method according to claim 5, wherein a black material is dispersed in the cationic electrodeposition resin.