JP-2026075065-A - Method for manufacturing an organic light-emitting element, and apparatus for manufacturing an organic light-emitting element

JP2026075065AJP 2026075065 AJP2026075065 AJP 2026075065AJP-2026075065-A

Abstract

[Problem] To provide a method for manufacturing an organic light-emitting element that reduces color mixing between different pixel regions, suppresses variations in the thickness of the light-emitting layer between pixel regions, and suppresses non-uniformity of the shape of the light-emitting layer within a pixel region. [Solution] A method for manufacturing an organic light-emitting element, comprising: a first liquid application step of applying a first liquid composition containing a first light-emitting material to a first pixel region; a first drying step of drying the inside of the first pixel region; a second liquid application step of applying a second liquid composition containing a second light-emitting material different from the first light-emitting material to a second pixel region; a vapor exposure step of exposing the first and second pixel regions to vapor of a solvent capable of dissolving the first and second light-emitting materials; and a second drying step of drying the inside of the first and second pixel regions, wherein the volume of the first liquid composition applied to the first pixel region is greater than the volume of the first pixel region, and the volume of the second liquid composition applied to the second pixel region is greater than the volume of the second pixel region. [Selection Diagram] Figure 7

Inventors

吉澤敦仁

Assignees

キヤノン株式会社

Dates

Publication Date: 20260507
Application Date: 20251007
Priority Date: 20241021

Claims (7)

A first liquid application step involves applying a first liquid composition containing a first light-emitting material to a first pixel region surrounded by a partition on a substrate, Following the first liquid application step, a first drying step is performed to dry the first pixel region, A second liquid application step is performed after the first drying step, in which a second liquid composition containing a second light-emitting material different from the first light-emitting material is applied to a second pixel region adjacent to the first pixel region and surrounded by a partition on the substrate. Following the second liquid application step, a vapor exposure step is performed in which the first pixel region and the second pixel region are exposed to a vapor of a solvent capable of dissolving both the first and second light-emitting materials. A method for manufacturing an organic light-emitting element, comprising: a second drying step after the steam exposure step, in which the first pixel region and the second pixel region are dried to form a first light-emitting layer containing the first light-emitting material in the first pixel region and a second light-emitting layer containing the second light-emitting material in the second image region, respectively, In the first liquid application step, the volume of the first liquid composition applied to the first pixel region is greater than the volume of the first pixel region. A method for manufacturing an organic light-emitting element, characterized in that the volume of the second liquid composition applied to the second pixel region in the second liquid application step is greater than the volume of the second pixel region.
The method for manufacturing an organic light-emitting element according to claim 1, characterized in that the second drying step is performed by reduced-pressure drying.
The method for manufacturing an organic light-emitting element according to claim 1, characterized in that the second liquid application step is performed in a wet state in which liquid components remain in the first liquid composition after drying in the first pixel region.
The method for producing an organic light-emitting element according to claim 1, characterized in that the boiling point of the solvent is 200°C or lower.
The method for manufacturing an organic light-emitting element according to claim 1, characterized in that the concentration of the first light-emitting material in the first liquid composition is 6% by mass or less based on the total mass of the first liquid composition, and the concentration of the second light-emitting material in the second liquid composition is 6% by mass or less based on the total mass of the second liquid composition.
In the first liquid application step, the volume of the first liquid composition applied to the first pixel region is five times or more the volume of the first pixel region. The method for manufacturing an organic light-emitting element according to claim 1, characterized in that, in the second liquid application step, the volume of the second liquid composition applied to the second pixel region is five times or more the volume of the second pixel region.
A first liquid application means for applying a first liquid composition containing a first light-emitting material to a first pixel region surrounded by a partition on a substrate, After the application of the first liquid composition by the first liquid application means, a first drying means for drying the first image region, A second liquid application means applies a second liquid composition containing a second light-emitting material different from the first light-emitting material to a second pixel region adjacent to the first pixel region and surrounded by a partition on the substrate, after drying by the first drying means. After the application of the second liquid composition by the second liquid application means, a vapor exposure means is provided to expose the first pixel region and the second pixel region to a vapor of a solvent capable of dissolving both the first and second light-emitting materials. An apparatus for manufacturing an organic light-emitting element, comprising: a second drying means for drying the first pixel region and the second pixel region after steam exposure by the steam exposure means, thereby forming a first light-emitting layer containing the first light-emitting material in the first pixel region and a second light-emitting layer containing the second light-emitting material in the second image region, respectively, The volume of the first liquid composition applied to the first pixel region by the first liquid application means is greater than the volume of the first pixel region. An apparatus for manufacturing an organic light-emitting element, characterized in that the volume of the second liquid composition applied to the second pixel region by the second liquid application means is greater than the volume of the second region.

Description

This invention relates to a method for manufacturing organic light-emitting elements and an apparatus for manufacturing organic light-emitting elements. An organic light-emitting element is an electronic device having a pair of electrodes, a first electrode and a second electrode, and an organic compound layer disposed between these electrodes. A known method for manufacturing organic light-emitting elements involves layering films of light-emitting materials, charge-transporting materials, and charge-injection materials. Hereinafter, the materials forming the organic compound layer of the organic light-emitting element, such as light-emitting materials, charge-transporting materials, and charge-injection materials, will be collectively referred to as functional materials. Vapor deposition is widely used as a manufacturing method for organic light-emitting elements. For example, when forming a light-emitting layer containing a light-emitting material on a substrate, a light-emitting material capable of emitting red, green, or blue light is deposited onto the substrate by vacuum deposition to form the light-emitting layer. When manufacturing organic light-emitting elements by vapor deposition, it is necessary to form a pattern that separates the film-forming area from the non-film-forming area using a mask. However, since the functional material is deposited on the mask in the non-film-forming area, there are challenges in the utilization rate of the functional material. In recent years, coating methods have been investigated as a manufacturing method for organic light-emitting diodes that can solve the above-mentioned problems in vapor deposition. In coating methods, an organic light-emitting diode is manufactured by applying a liquid composition containing functional materials to a substrate. For example, an inkjet method is being investigated for coating the liquid composition onto the substrate. In the case of the inkjet method, the liquid composition can be selectively applied to the film-forming area, reducing waste of functional materials in the non-film-forming area. This improves the utilization rate of functional materials and is considered to have cost advantages compared to vapor deposition. In the coating method, pixel regions are separated by partitions on all four sides, and a liquid composition containing a functional material is applied within these partitions. However, if liquid compositions applied to different pixel regions, especially adjacent pixel regions, come into contact and mix, it can lead to issues such as color mixing. Therefore, various measures to suppress the mixing of liquid compositions are being considered. Patent Document 1 discloses a method in which a small amount of a liquid composition containing a functional material is applied to a region surrounded by partitions, and areas where filling defects occur are exposed to the vapor of a low-boiling point solvent to wet and spread the liquid composition throughout the entire region. Japanese Patent Publication No. 2012-248297 This is a schematic diagram of an organic light-emitting element substrate.This is a schematic diagram illustrating the mechanism by which color mixing occurs on an organic light-emitting element substrate.This is a schematic diagram illustrating the mechanism by which non-uniformity of the light-emitting layer shape occurs within the pixel region.This is a schematic diagram of an organic light-emitting element substrate and ink application.This is an example of the shape of the first light-emitting layer formed within the pixel region.This is an example of the shape of the first light-emitting layer formed within the pixel region.This is a schematic diagram showing the process of forming the light-emitting layer according to this embodiment. The present invention will be further described in detail below with reference to preferred embodiments. It will be readily apparent to those skilled in the art that the present invention is not limited to the following description, and that its form and details can be modified in various ways without departing from the spirit and scope of the invention. That is, the present invention should not be interpreted as being limited by the following description. Unless otherwise specified, the physical properties are values at room temperature (25°C). The inventors of this invention investigated a method for manufacturing an organic light-emitting element that can reduce color mixing between different pixel regions, suppress variations in the thickness of the light-emitting layer between pixel regions, and suppress non-uniformity of the shape of the light-emitting layer within a pixel region. As a result, they found that this problem can be solved by the following configuration, leading to the present invention. In other words, the method for manufacturing an organic light-emitting element according to the present invention comprises a first liquid application step, a