KR-20260063387-A - Large mask sheet

KR20260063387AKR 20260063387 AKR20260063387 AKR 20260063387AKR-20260063387-A

Abstract

The present invention provides a large mask sheet comprising a plurality of individual mask sheets, each having a plurality of opening holes formed on the inner side, connected by welding adjacent edge portions, wherein a first joining portion having a plurality of alignment protrusions is provided on one side of each individual mask sheet and protrudes outwardly, and a second joining portion having a plurality of alignment coupling grooves that engage with the alignment protrusions is provided on the other side of each individual mask sheet and protrudes outwardly, and wherein adjacently arranged individual mask sheets are joined using the alignment protrusions formed on one side of the individual mask sheet and the alignment coupling grooves formed on the other side of the individual mask sheet, and then the one side and the other side of the connected individual mask sheet are welded together.

Inventors

강호민
이승필

Assignees

(주)세우인코퍼레이션

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (7)

In a large mask sheet formed by welding adjacent edge portions of multiple individual mask sheets, each having multiple opening holes formed on the inner side, On one side of each of the above individual mask sheets, a first bonding portion having a plurality of alignment protrusions is provided to protrude outwardly, and On the other side of the individual mask sheet, a plurality of alignment coupling grooves coupled with the alignment projection are provided such that the second joining portion protrudes outwardly. A large mask sheet characterized by joining adjacent individual mask sheets using the alignment protrusion formed on one side of the individual mask sheet and the alignment coupling groove formed on the other side of the individual mask sheet, and then welding the one side and the other side of the connected individual mask sheet.
In claim 1, The first bonding portion protrudes outward from one side of the individual mask sheet to the lower surface of the individual mask sheet, and A large mask sheet characterized in that the second joining portion protrudes outward from the upper surface of the individual mask sheet on the other side of the individual mask sheet in correspondence with the first joining portion.
In claim 2, A large mask sheet characterized in that the protrusion length (L1) of the first bonding section protruding outward from one side of the individual mask sheet and the protrusion length (L2) of the second bonding section protruding outward from the other side of the individual mask sheet are the same.
In claim 3, The height (H1) of the first bonding portion protruding outward from one side of the individual mask sheet is greater than 1/3 and less than 1/2 of the height (H) of the individual mask sheet, and A large mask sheet characterized in that the height (H2) of the second bonding portion protruding outward from the other side of the individual mask sheet is greater than 1/2 and less than 2/3 of the height (H) of the individual mask sheet.
In claim 4, A plurality of alignment protrusions are formed on the upper surface of the first joint section, and A large mask sheet characterized in that the height (h1) of the alignment protrusion is less than or equal to 1/2 of the height (H1) of the first bonding section.
In claim 5, The plurality of alignment protrusions are formed on the upper surface of the first bonding section at a distance from each other in the longitudinal direction of the individual mask sheet, and A large mask sheet characterized in that the plurality of alignment joint grooves are formed on the lower surface of the second joining section at a distance from each other in the longitudinal direction of the individual mask sheet.
In claim 6, The above alignment protrusion has a cross-sectional shape selected from a circular shape, a triangular shape, a square shape, a polygonal shape, a cross shape, and a star shape, A large mask sheet characterized in that the above alignment coupling groove has a shape corresponding to the cross-sectional shape of the above alignment projection.

Description

Large mask sheet The present invention relates to a large mask sheet, and more specifically, to a large mask sheet manufactured by connecting a plurality of individual mask sheets, each having a plurality of opening holes formed on the inner side, to adjacent edge portions by welding. Referring to the background technology described in Korean Registered Patent No. 10-2427524 (registered on July 27, 2022), generally known flat panel display devices include Liquid Crystal Display Devices (LCDs) and Organic Light Emitting Display Devices (OLEDs). Among these, an OLED is a thin-film light-emitting diode in which the light-emitting layer is composed of an organic compound. A typical OLED manufacturing process involves performing an evaporation process using a mask assembly equipped with corresponding patterns when stacking and patterning thin film layers, such as an electrode layer, an organic light-emitting layer, and an insulating film. During the deposition process, an open metal mask (hereinafter referred to as OMM) is used to form a common organic layer that performs a functional role on the OLED substrate, while a fine metal mask (hereinafter referred to as FMM) is used in the RGB deposition process to deposit pixels emitting three types of light, such as red (R), green (G), and blue (B). The mask assembly used in the deposition process has a structure in which a relatively thin metal film, such as a mask sheet or a mask stick, is bonded onto a mask frame having a relatively sturdy structure. The mask frame is a frame structure in the form of a window frame or door frame with a thickness of about 5 to 80 mm and performs the function of stably maintaining the shape of the mask assembly. Meanwhile, the mask sheet or mask stick is formed by forming a predetermined pattern to be used during deposition on a thin metal sheet or strip having a thickness of about 0.01 to 5.00 mm. A typical mask assembly is manufactured using a metal with a very small coefficient of thermal expansion with temperature change, such as Invar-36 Alloy. Furthermore, in cases where high precision of the pattern is not required, the mask frame may be manufactured using heat-resistant stainless steel, such as SUS420, to reduce costs. As an example, an open metal mask (OMM) assembly used in the organic common layer deposition process for OLED displays can be manufactured by coating a dry photosensitive film (DFR) on both sides of a mask sheet, performing UV exposure, forming a pattern on the mask sheet through processes such as development and wet etching, and then joining it to a mask frame by laser welding while in a stretched state. With the demand for large-area OLED panels ranging from the 6th to 8th generation increasing significantly today, the maximum size of the Invar alloy mask sheet source currently supplied is only about 1,100 mm in width. Since it is impossible to manufacture a mask assembly for large-area OLEDs using the mask sheet source, a method of welding multiple mask sheet sources together and joining them to a frame is used. However, if the welded joints of the mask sheet sources connected by welding burst, the adjacent mask sheet sources cannot support each other, resulting in a problem where the manufactured large-area mask sheet cannot perform its function properly. FIG. 1 is a schematic plan view illustrating a large mask sheet according to an embodiment of the present invention. Figure 2 is a diagram illustrating the process of combining adjacent individual mask sheets to manufacture a large mask sheet shown in Figure 1. Figure 3 is a drawing showing the welded state of the combined individual mask sheets shown in Figure 2. Figure 4 is a cross-sectional view of the combined individual mask sheets shown in Figure 3. FIGS. 5 and 6 are plan views of individual mask sheets having alignment protrusions and alignment coupling grooves formed therein according to other embodiments. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, and should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Referring to FIGS. 1 to 4, a large mask sheet (10) according to an embodiment of the present invention is manufactured by connecting a plurality of individual mask sheets (100), each having a plurality of opening holes (100a) formed on the inside, to adjacent edge portions by welding (W), and each individual mask sheet (100) is provided with a first joining portion (110) and a second joining portion (120). The first bonding member (110) is provided to protrude outward from one side of each individual mask sheet (100), and the