CN110724905A

CN110724905A - Mask sheet, mask plate and preparation method thereof

Info

Publication number: CN110724905A
Application number: CN201911012834.3A
Authority: CN
Inventors: 曾佳; 陈奎; 贺雪英; 曹东旭; 张雷
Original assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Priority date: 2019-10-23
Filing date: 2019-10-23
Publication date: 2020-01-24
Anticipated expiration: 2039-10-23
Also published as: CN110724905B

Abstract

The invention provides a mask sheet, a mask plate and a preparation method thereof, relates to the technical field of display, and can improve the evaporation effect of the mask plate. The mask plate comprises a frame and a plurality of mask sheets arranged on the frame in a spanning mode. The mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body part is provided with a plurality of first pixel holes. The sum of the thicknesses of the first splicing part and the second splicing part is equal to the thickness of the main body part; the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part; in any adjacent mask sheets, the first spliced portion of one mask sheet overlaps the second spliced portion of the other mask sheet. A plurality of second pixel holes are formed in the region between the main body portions of any adjacent mask pieces, and all the first pixel holes and all the second pixel holes are arrayed and uniformly distributed on the whole.

Description

Mask sheet, mask plate and preparation method thereof

Technical Field

The invention relates to the technical field of display, in particular to a mask sheet, a mask plate and a preparation method of the mask sheet.

Background

Organic Light-Emitting diodes (OLEDs), also known as Organic electroluminescent displays and Organic Light-Emitting semiconductors, have the advantages of self-luminescence, wide viewing angle, high contrast, low power consumption, and high response speed.

Various film layers are often included in OLED display devices, including, for example, anodes, cathodes, light emitting layers, and the like. Therefore, when the OLED display device is manufactured, each film layer in the OLED display device needs to be evaporated onto a glass substrate to be evaporated through an evaporation process, and for evaporation of some film layers, an FMM (Fine Metal MASK) needs to be used, and evaporation materials are evaporated to a designed position through a through hole in the FMM to form a designed film layer pattern.

Disclosure of Invention

The embodiment of the invention provides a mask sheet, a mask plate and a preparation method of the mask plate, which can improve the evaporation effect of the mask plate and reduce the maintenance cost of the mask plate.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

on one hand, the mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body portion is provided with a plurality of first pixel holes.

The sum of the thicknesses of the first splicing part and the second splicing part is equal to the thickness of the main body part; the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part.

Optionally, the thickness of the first splicing part is equal to the thickness of the second splicing part.

In another aspect, a mask plate is provided, which includes a frame and a plurality of mask sheets spanning the frame.

The mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body portion is provided with a plurality of first pixel holes.

The sum of the thicknesses of the first splicing part and the second splicing part is equal to the thickness of the main body part; the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part; in any adjacent ones of the mask sheets, the first spliced portion of one of the mask sheets overlaps the second spliced portion of the other mask sheet.

And a plurality of second pixel holes are formed in the region between the main body parts of any adjacent masks, and all the first pixel holes and all the second pixel holes are arrayed and uniformly distributed on the whole.

Optionally, the width of the second splicing part is greater than the width of the first splicing part.

In the region between the main body portions of any adjacent mask sheets, a part of the second pixel holes only penetrate through the second splicing portion, and a part of the second pixel holes simultaneously penetrate through the second splicing portion and the first splicing portion.

Optionally, in any two adjacent mask sheets, a gap is provided between the second spliced portion of one of the mask sheets and the main body portion of the other mask sheet.

The pitch is smaller than a distance between two adjacent first pixel holes in a width direction of the mask sheet.

Optionally, the pitch ranges from 10 μm to 500 μm.

In another aspect, a method for manufacturing a mask is provided, where the mask includes: a plurality of mask sheets; the mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body portion is provided with a plurality of first pixel holes.

The thickness sum of the first splicing part and the second splicing part is equal to the thickness of the main body part, the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part.

The preparation method of the mask plate comprises the following steps:

sequentially screen-welding a plurality of mask sheets to a frame, and overlapping the first spliced portion of one of the mask sheets with the second spliced portion of the other of any two adjacent mask sheets.

And a plurality of second pixel holes are formed in the region between the main body parts of any adjacent mask sheets, and all the first pixel holes and all the second pixel holes are arrayed and uniformly distributed on the whole.

Optionally, forming a plurality of second pixel holes in a region between the main body portions of any adjacent mask sheets includes:

and placing the frame on a laser processing machine table, and enabling the mask sheet to be tightly attached to the laser processing machine table through a magnetic force generating device positioned below the laser processing machine table.

And punching a region between the main body portions of any adjacent mask sheets by using a laser emitter to form a plurality of second pixel holes.

Placing the frame on a laser processing machine table, including:

and turning the frame for 180 degrees and placing the frame on a laser processing machine table to enable the second splicing part to be in contact with the laser processing machine table.

Optionally, forming the mask sheet includes:

the mask sheet body is divided into three areas, namely a middle area and edge areas respectively positioned at two sides of the middle area.

Etching the edge area of the mask sheet body by a half-etching technology to respectively form the first splicing part and the second splicing part; the main body part is the mask sheet body positioned in the middle area.

The embodiment of the invention provides a mask, a mask plate and a preparation method thereof, wherein the mask plate comprises a plurality of mask sheets, and a first splicing part and a second splicing part are arranged on two sides of a main body part of each mask sheet; in any adjacent mask sheets, the first spliced portion of one mask sheet is overlapped with the second spliced portion of the other mask sheet, and a plurality of second pixel holes are formed in the region between the main body portions of any adjacent mask sheets. On one hand, the plurality of masking sheets are arranged, only the damaged masking sheet needs to be replaced, and the masking sheets are small in size, small in gravity and small in sagging amount along the thickness direction, so that the color mixing defect can be improved, and the evaporation effect is improved; meanwhile, the width of the mask sheet is small, so that wrinkles are not easy to appear when the net is stretched, the color mixing defect can be further improved, and the evaporation effect is improved. On the other hand, in any adjacent mask, the first splicing portion of one mask overlaps with the second splicing portion of the other mask, the lower surface of the first splicing portion is flush with the lower surface of the main body, the upper surface of the second splicing portion is flush with the upper surface of the main body, and the sum of the thicknesses of the first splicing portion and the second splicing portion is equal to the thickness of the main body. In another aspect, a plurality of second pixel holes are formed in the region between the main body portions of any adjacent mask sheets, each second pixel hole can be machined at a time after the mask sheet is welded to the frame, and the requirements on machining accuracy and alignment accuracy of the mask sheets are low. Therefore, the mask plate provided by the embodiment of the invention can solve the problems of large sagging amount, more folds, higher production and maintenance cost and poorer evaporation effect of the mask plate in the related technology.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1a is a schematic structural diagram of an OLED display panel according to an embodiment of the present invention;

fig. 1b is a schematic structural diagram of a light emitting device according to an embodiment of the present invention;

fig. 1c is a schematic structural diagram of a light-emitting functional layer according to an embodiment of the present invention;

fig. 2a is a schematic top view of a mask according to an embodiment of the present invention;

FIG. 2b is a schematic cross-sectional view taken along line A-A' of FIG. 2 a;

fig. 3a is a schematic top view of another mask according to an embodiment of the present invention;

FIG. 3B is a schematic cross-sectional view taken along line B-B' of FIG. 3 a;

fig. 4a is a schematic top view of another mask according to an embodiment of the present invention;

FIG. 4b is a schematic cross-sectional view taken along line C-C' of FIG. 4 a;

fig. 5a is a schematic top view of another mask according to an embodiment of the present invention;

FIG. 5b is a schematic cross-sectional view taken along line D-D' of FIG. 5 a;

fig. 6a is a schematic top view of another mask according to an embodiment of the present invention;

FIG. 6b is a schematic cross-sectional view taken along line E-E' of FIG. 6 a;

FIG. 7 is a schematic diagram illustrating a top view structure of a mask according to the related art;

FIG. 8a is a schematic top view of a mask according to another related art;

FIG. 8b is a schematic cross-sectional view taken along line G-G' of FIG. 8 a;

FIG. 8c is another schematic cross-sectional view taken along line G-G' of FIG. 8 a;

fig. 9a is a schematic flow chart of a mask manufacturing method according to an embodiment of the present invention;

fig. 9b is a schematic view of a manufacturing process of a mask according to an embodiment of the present invention;

FIG. 9c is a schematic cross-sectional view taken in the direction H-H' of FIG. 9 b;

fig. 9d is a schematic view of a manufacturing process of another mask according to an embodiment of the present invention;

fig. 10a to fig. 10d are schematic views illustrating a manufacturing process of another mask according to an embodiment of the present invention;

FIG. 11a is a schematic view of a process for preparing a mask sheet according to an embodiment of the present invention;

FIG. 11b is a schematic structural diagram of a mask according to an embodiment of the present invention;

FIG. 11c is a schematic cross-sectional view taken along line I-I' of FIG. 11 b.

Reference numerals:

1-an OLED display panel; 10-a substrate; 11-a light emitting device; 110-an anode; 111-a cathode; 112-a light-emitting functional layer; 1120-a light emitting layer; 12-a light filtering unit; 13-a pixel drive circuit; 2-a mask plate; 20-a frame; 21-a mask sheet; 210-a body portion; 2100-a first pixel aperture; 211-a first splice; 212-a second splice; 213 — the area between the body portions; 2130-a second pixel aperture; 214-pixel aperture; 214-a stretching section; 22-first mask stripes; 23-second mask stripes; 24-pixel aperture; 3-a laser processing device; 31-a laser processing machine; 32-a magnetic force generating device; 33-a laser emitter; 4-mask slice body; 41-middle zone; 42-edge region; 5-a connecting part.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

With the development of display technology, flexible display technology represented by an OLED (Organic Light-Emitting Diode) display device has attracted more and more attention. Compared with the liquid crystal display device, the OLED display device has the excellent characteristics of self-luminescence, no need of a backlight source, high contrast ratio, thin thickness, wide viewing angle, fast response speed, flexibility, wide temperature range of use, simpler structure and process, and the like, and is considered as a new application technology of the next generation of flat panel display.

In the OLED display device, the quality of the OLED display panel is the most important factor for determining the quality of the OLED display device, and therefore, attention needs to be paid to the manufacturing process of the OLED display panel.

As shown in fig. 1a, the OLED display panel 1 includes a substrate 10, a light emitting device 11 disposed on the substrate 10 and in each sub-pixel.

By way of example, the substrate 10 may be a flexible substrate, and the material thereof may be polyimide, for example.

As shown in fig. 1b, the light emitting device 11 comprises an anode 110, a cathode 111, and a light emitting functional layer 112 located between the anode 110 and the cathode 111. The light emitting device 11 may be classified into a bottom emission type, a top emission type, and a double-sided emission type. Taking the anode 110 close to the substrate 10 and the cathode 111 located at the side of the anode 110 far from the substrate 10 as an example, when the light emitting device 11 is of a bottom emission type, the material of the anode 110 may be a transparent conductive material such as ITO (Indium Tin oxide); the material of the cathode 111 is a metal, which may be, for example, silver; when the light emitting device 11 is of a top emission type, the anode 110 has a multilayer laminated structure including a transparent conductive layer and an opaque metal layer, for example, a three-layer laminated structure of ITO/Ag/ITO, and the cathode 111 is made of metal, in which case, the cathode 111 is thin and semi-transparent; when the light emitting device 11 is a double-sided light emitting type, the anode 110 is made of a transparent conductive material, the cathode 111 is made of a metal, and the cathode 111 is thin and translucent.

The light-emitting function layer 112 includes at least a light-emitting layer. The light emitting layer serves to generate light by the anode 110 and the cathode 111.

As shown in fig. 1c, the light-emitting function layer 112 may optionally include, in addition to the light-emitting layer 1120, an ETL (electron transport layer) 1121, an EIL (electron injection layer) 1122, an HTL (hole transport layer) 1123, and an HIL (hole injection layer) 1124. It should be noted that the light-emitting functional layer 112 is not limited to include only the combination of the light-emitting layer 1120 and the ETL1121, EIL1122, HTL1123, and HIL1124, and may include other functional layers.

The material of the light emitting layer 1120 may be, for example, an organic light emitting material, and the material of the light emitting layer 1120 determines the light emitting color of the light emitting device 11.

For the light emitting device 11, the light emitting color thereof may be one of three primary colors, which may be, for example, red, green, and blue. Illustratively, as shown in fig. 1a, the plurality of sub-pixels includes a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B. One light emitting device 11 is included in each of the red, green, and blue sub-pixels R, G, and B. Wherein, in the red subpixel R, the light emitting device 11 is for emitting red light; in the green subpixel G, the light emitting device 11 is configured to emit green light; in the blue subpixel B, the light emitting device 11 is configured to emit blue light.

It will be appreciated that the light emitting devices 11 located in each sub-pixel are fabricated simultaneously at the time of fabrication.

At least when the light emitting layer 1120 in the light emitting device 11 is manufactured, a mask made of a metal material is used to deposit an organic light emitting material by a vacuum evaporation technique to form the light emitting layer 1120.

Based on the above, as shown in fig. 2a to 6b, an embodiment of the invention provides a mask 2, which includes a frame 20 and a plurality of mask sheets 21 straddling the frame 20.

The mask sheet 21 comprises a main body portion 210, a first spliced portion 211 and a second spliced portion 212, wherein the first spliced portion 211 and the second spliced portion 212 are located on two sides of the main body portion 210 in the width direction of the mask sheet 21; the body portion 210 is provided with a plurality of first pixel holes 2100.

The sum of the thicknesses of the first and

second splices

211, 212 is equal to the thickness of the body portion 210; the lower surface of the first splicing part 211 is flush with the lower surface of the main body part 210, and the upper surface of the second splicing part 212 is flush with the upper surface of the main body part 210; in any adjacent mask sheets 21, the first spliced portion 211 of one mask sheet 21 overlaps the second spliced portion 212 of the other mask sheet 21.

A plurality of second pixel holes 2130 are provided in the region 213 between the main body portions 210 of any adjacent mask sheets 21, and all of the first pixel holes 2100 and all of the second pixel holes 2130 are arrayed and uniformly arranged as a whole.

As shown in fig. 2a to 6b, the main body portion 210 is provided with a plurality of first pixel holes 2100 uniformly arranged in an array, and the plurality of first pixel holes 2100 may be formed by etching or laser.

The sum of the thicknesses of the first splicing part 211 and the second splicing part 212 arranged on the two sides of the width direction of the main body part 210 is equal to the thickness of the main body part 210, and the three conditions that the thickness of the first splicing part 211 is larger than that of the second splicing part 212, the thickness of the first splicing part 211 is equal to that of the second splicing part 212, and the thickness of the first splicing part 211 is smaller than that of the second splicing part 212 are included.

Optionally, the thickness of the first splicing portion 211 is equal to the thickness of the second splicing portion 212.

In the following description, taking as an example that any two adjacent mask sheets 21 are respectively a first mask sheet and a second mask sheet, the region 213 between the main body portions 210 of the two adjacent mask sheets 21 and the second pixel hole 2130 respectively include the following cases:

the first method comprises the following steps: as shown in fig. 2a and 2b, the width of the first splicing portion 211 is equal to the width of the second splicing portion 212, and the orthographic projections of the first splicing portion 211 of the second mask sheet and the second splicing portion 212 of the first mask sheet completely coincide with each other in the thickness direction of the mask sheet 21. In this case, the region 213 between the main body portions 210 of the two adjacent masks 21 is the region of the first mask where the second spliced portion 212 of the second mask is located. As can be seen, in the region 213 between the main body portions 210 of any adjacent mask sheets 21, each of the second pixel holes 2130 penetrates the stacked first and second spliced

portions

211 and 212.

And the second method comprises the following steps: as shown in fig. 3a and 3b, the width of the first splicing portion 211 is equal to the width of the second splicing portion 212, and the orthographic projections of the first splicing portion 211 of the second mask sheet and the second splicing portion 212 of the first mask sheet overlap in the thickness direction of the mask sheet 21. In this case, the region 213 between the main body portions 210 of the adjacent two mask sheets 21 includes: the orthographic overlap of the second stitching 212 of the first mask sheet and the first stitching 211 of the second mask sheet, the separation H between the main body portion 210 of the first mask sheet and the first stitching 211 of the second mask sheet, and the separation H between the main body portion 210 of the second mask sheet and the second stitching 212 of the first mask sheet. Here, in order to ensure that the second pixel holes 2130 are formed in the region 213 between the body portions 210 of any two adjacent mask sheets 21 and that the formed second pixel holes 2130 and the first pixel holes 2100 are uniformly distributed, H may be smaller than the distance L between any two adjacent first pixel holes 2100.

Based on this, in the width direction of the mask sheet 21, according to the width of the orthographic overlapping area of the second spliced portion 212 of the first mask sheet and the first spliced portion 211 of the second mask sheet 21, and the size of h, the second pixel hole 2130 may be disposed in the orthographic overlapping area of the second spliced portion 212 of the first mask sheet and the first spliced portion 211 of the second mask sheet 21, where the second pixel hole 2130 penetrates through the stacked first spliced portion 211 and the second spliced portion 212; and/or, the second pixel hole 2130 may also be disposed between the main body portion 210 of the first mask sheet and the first splicing portion 211 of the second mask sheet, in which case the second pixel hole 2130 only penetrates through the second splicing portion 212 of the first mask sheet.

And the third is that: as shown in fig. 4a and 4b, the width of the first spliced portion 211 is smaller than the width of the second spliced portion 212, and the orthographic projections of the first spliced portion 211 of the second mask sheet and the second spliced portion 212 of the first mask sheet overlap in the thickness direction of the mask sheet 21. In this case, the region 213 between the main body portions 210 of the adjacent two mask sheets 21 includes: the orthographic overlap of the second stitching 212 of the first mask sheet and the first stitching 211 of the second mask sheet, the separation H between the main body portion 210 of the first mask sheet and the first stitching 211 of the second mask sheet, and the separation H between the main body portion 210 of the second mask sheet and the second stitching 212 of the first mask sheet. Here, H may be smaller than a distance L between any two adjacent first pixel holes 2100, in order to ensure that the second pixel holes 2130 are formed in the region 213 between the body portions 210 of any two adjacent mask pieces 21, and the formed second pixel holes 2130 and the first pixel holes 2100 are uniformly distributed in an array as a whole.

And fourthly: as shown in fig. 5a and 5b, the width of the first spliced portion 211 is smaller than the width of the second spliced portion 212, and the orthographic projections of the first spliced portion 211 of the second mask sheet and the second spliced portion 212 of the first mask sheet overlap in the thickness direction of the mask sheet 21. In this case, the region 213 between the main body portions 210 of the adjacent two mask sheets 21 includes: the orthographic overlap of the second stitching 212 of the first mask and the first stitching 211 of the second mask, and the separation h between the main body portion 210 of the first mask and the first stitching 211 of the second mask.

And a fifth mode: as shown in fig. 6a and 6b, the width of the first spliced portion 211 is greater than the width of the second spliced portion 212, and the orthographic projections of the first spliced portion 211 of the second mask sheet and the second spliced portion 212 of the first mask sheet overlap in the thickness direction of the mask sheet 21. In this case, the region 213 between the main body portions 210 of the adjacent two mask sheets 21 includes: the orthographic overlap of the second stitching 212 of the first mask and the first stitching 211 of the second mask, and the separation H between the main body portion 210 of the second mask and the second stitching 212 of the first mask. Here, in order to ensure that the second pixel holes 2130 are formed in the region 213 between the body portions 210 of any two adjacent mask sheets 21 and that the formed second pixel holes 2130 and the first pixel holes 2100 are uniformly distributed, H may be smaller than the distance L between any two adjacent first pixel holes 2100.

Based on this, in the width direction of the mask sheet 21, according to the width of the orthographic overlapping area of the second spliced portion 212 of the first mask sheet and the first spliced portion 211 of the second mask sheet 21, and the size of H, the second pixel hole 2130 is provided in the orthographic overlapping area of the second spliced portion 212 of the first mask sheet and the first spliced portion 211 of the second mask sheet 21, and at this time, the second pixel hole 2130 penetrates through the stacked first spliced portion 211 and second spliced portion 212.

On the basis of the above, since all the first pixel holes 2100 and all the second pixel holes 2130 are arrayed and uniformly arranged as a whole, it can be understood that the plurality of second pixel holes 2130 disposed in the region 213 between the main body portions 210 of any adjacent mask pieces 21 are arrayed and uniformly arranged, and the distance between any two adjacent second pixel holes 2130 is equal to the distance between any two adjacent first pixel holes 2100. That is, the distance between any adjacent two of the second pixel holes 2130 in the width direction of the mask sheet 21 is also equal to L.

In this case, when the second pixel holes 2130 are formed in the region 213 between the main body portions 210 of any adjacent mask sheets 21, the second pixel holes 2130 distributed uniformly can be prepared, and when the distance between the adjacent second pixel holes 2130 is equal to L, the distance between the second pixel holes 2130 and the adjacent first pixel holes 2100 is also equal to L, so that the second pixel holes 2130 and the first pixel holes 2100 are uniformly distributed in an array as a whole. The second pixel hole 2130 of the region 213 located between the main body portions 210 of any adjacent mask sheets 21 may penetrate only the second spliced portion 212, or may penetrate both the first spliced portion 211 and the second spliced portion 212.

Alternatively, the top views of the first and second pixel holes 2100 and 2130 may be, for example, a quadrangle, a hexagon, a circle, and the like. As an example, the first and second pixel holes 2100 and 2130 have a quadrilateral top view, and the longitudinal section thereof may be, for example, a trapezoid, that is, the structure of the second pixel hole 2130 as shown in fig. 2b, 3b, 4b, 5b, and 6 b.

When the mask 2 is used, as shown in fig. 2a to 6b, the surface of the upper surface of the second splicing portion 212 and the surface of the upper surface of the main body portion 210 may be a side surface of the mask 2, which is close to a glass substrate to be evaporated when in use.

As shown in fig. 2a to 6b, the main body portion 210 has 3 columns of first pixel holes 2100, and the region 213 between the main body portions 210 of two adjacent mask sheets 21 has 2 columns of second pixel holes 2130, which is merely an example and is not limited in this embodiment of the present invention. Here, since the width of the main body portion 210 is much larger than the width of the region 213 between the main body portions 210 of two adjacent mask sheets 21, the number of the first pixel holes 2100 located in the main body portion 210 is actually much larger than the number of the second pixel holes 2130. The present invention is directed to clearly present the structural features of the regions 213 between the main body 210 and the main bodies 210 of two adjacent mask sheets 21, thereby reducing the difference in width between the two.

As shown in fig. 7, in a related art, the mask 2 includes a frame 20 and a first mask stripe 22, and a plurality of pixel holes 24 are formed on the first mask stripe 22. The first mask stripes 22 are stretched and then welded to the frame 20. When the tensioned net is stretched, a tensile stress is generated inside the first mask stripes 22, and the tensile stress is used for offsetting a thermal stress generated when the first mask stripes 22 are heated in evaporation, wherein the thermal stress is generated because the first mask stripes 22 expand after being heated. Both sides of the first mask stripes 22 in the width direction are welded to the frame 20, and the stretching is not performed in this direction during the stretching, and only both sides of the first mask stripes 22 in the length direction, i.e., the Y direction shown in fig. 7, are stretched in the width direction, i.e., the X direction shown in fig. 7, and both sides of the first mask stripes 22 in the length direction are welded to the frame 20. That is, during the stretching of the web, the first mask stripes 22 are not subjected to a tensile force in the width X direction, but are subjected to a tensile force only in the length Y direction. And when the coating by vaporization, because the influence of thermal stress and the gravity of first mask strip 22 to lead to this first mask strip 22 width to increase, and then make along the great sag that appears of the thickness direction of this first mask strip 22, this sag can influence mask plate 2 and the inseparable degree of treating the laminating of coating by vaporization glass substrate, cause the colour mixture defect. In the Y direction of the length of the first mask stripes 22, although the tensile stress generated during stretching can counteract the thermal stress, the length increase of the first mask stripes 22 in the Y direction is reduced to avoid a large sagging amount along the thickness direction of the first mask stripes 22. However, since the first mask stripes 22 have a large size, the required tensile stress is also large, and since the thickness of the first mask stripes 22 is small, the first mask stripes 22 themselves are relatively thin, when the tensile stress generated during stretching is larger than the buckling critical load of the first mask stripes 22 themselves, a plurality of wrinkles extending and distributed along the X direction are generated on the first mask stripes 22, and the wrinkles further increase the probability of occurrence of color mixing, thereby affecting the evaporation effect of the mask plate 2. Meanwhile, in the related art, a large-sized first mask stripe 22 is used, and when there is partial damage to the first mask stripe 22, the entire first mask stripe 22 needs to be replaced, and the maintenance cost of the mask plate 2 is high.

As shown in fig. 8a, in another related art, a plurality of second mask stripes 23 are spanned on the frame 20, half of the pixel apertures 24 are respectively disposed at the edges of the adjacent second mask stripes 23, and after two second mask stripes 23 are spliced, the two half of the pixel apertures 24 at the edges of the two second mask stripes can be spliced to form a complete pixel aperture 24. In this related art, since one pixel aperture 24 is divided into two parts, the processing accuracy requirement for the edges of the second mask stripes 23 is high. As shown in fig. 8b, the pixel holes 24 having shapes meeting the design requirements can be formed only when the processing accuracy is high, and the stretching accuracy and the alignment accuracy are high, but even if this is done, the cost increase for improving the processing accuracy and the stretching accuracy and the alignment accuracy is not negligible. However, even if the processing accuracy can be achieved, due to the influence of transportation and stretching, the edges of the second mask strips 23 are also easy to deform, and the deformed edges of the two second mask strips 23 cannot be spliced into the pixel holes 24 with the shape meeting the design requirements. As shown in fig. 8c, under the conditions that the processing precision, the stretching precision and the alignment precision are low, and the edges of the second mask strips 23 are deformed, the two second mask strips 23 cannot be spliced into the pixel holes 24 with the shapes meeting the design requirements, and when the mask plate 2 is used for vapor deposition, the vapor deposition effect is poor.

With the development of the OLED technology, the display panel prepared by using the OLED technology can be applied to not only small-sized mobile phones, but also large-and-medium-sized display devices such as notebook computers and vehicle-mounted displays. However, as the size of the display panel increases, the size of the mask used to fabricate the display panel inevitably increases, and as shown in fig. 7, if the first mask stripes 22 of an excessively large size are used in a whole sheet, two problems are mainly caused: firstly, along the thickness direction of the mask plate 2, the drooping amount of the first mask stripes 22 is increased; secondly, an increase in the width of the first mask stripes 22 along the X-direction increases the risk of the first mask stripes 22 wrinkling during stretching. Alternatively, as shown in fig. 8a, if the mask 2 is prepared by splicing a plurality of second mask strips 23, the requirements for the processing precision, the stretching precision and the alignment precision are all high, which inevitably results in the problems of reduced product yield and increased production cost, and when the above various precisions are low, the risk of color mixing is also increased. Therefore, the above two related technologies both increase the color mixing risk during evaporation, and the evaporation effect is poor, thereby affecting the final quality of the display panel.

Therefore, in order to solve the problems in the related art, in the mask plate 2 provided in the embodiment of the present invention, a plurality of mask sheets 21 are included, and a first splicing portion 211 and a second splicing portion 212 are disposed on two sides of a main body portion 210 of each mask sheet 21; in any adjacent mask sheets 21, the first spliced portion 211 of one mask sheet 21 overlaps the second spliced portion 212 of the other mask sheet 21, and a region 213 between the main body portions 210 of any adjacent mask sheets 21 is provided with a plurality of second pixel holes 2130. On one hand, the plurality of masking sheets 21 are arranged, only the damaged masking sheet 21 needs to be replaced, and the plurality of masking sheets 21 are small in size, small in gravity and small in sagging amount along the thickness direction, so that the color mixing defect can be improved, and the evaporation effect can be improved; meanwhile, because the width of the mask sheet 21 is small, wrinkles are not easy to appear when the expanded mesh is stretched, the color mixing defect can be further improved, and the evaporation effect is improved. On the other hand, in any adjacent mask sheets 21, the first spliced portion 211 of one mask sheet 21 overlaps with the second spliced portion 212 of the other mask sheet 21, and under the condition that the lower surface of the first spliced portion 211 is flush with the lower surface of the main body portion 210, the upper surface of the second spliced portion 212 is flush with the upper surface of the main body portion 210, and the sum of the thicknesses of the first spliced portion 211 and the second spliced portion 212 is equal to the thickness of the main body portion 210, when alignment and stretch welding is performed, only the width of the area 213 between the main body portions 210 of any adjacent mask sheets 21 needs to be controlled, and the requirements on the alignment accuracy, the stretch welding accuracy and the machining accuracy of the mask sheets 21 are low. On the other hand, a plurality of second pixel holes 2130 are provided in the region 213 between the main body portions 210 of any adjacent mask sheets 21, and each of the second pixel holes 2130 can be processed at a time after the mask sheet 21 is welded to the frame 20, and the processing accuracy and the alignment accuracy of the mask sheets 21 are also required to be low. Therefore, the mask plate 2 provided by the embodiment of the invention can solve the problems of large drooping amount, more folds, high production and maintenance cost and poor evaporation effect of the mask plate 2 in the related technology.

Optionally, as shown in fig. 4b and 5b, the width of the second splicing portion 212 is greater than the width of the first splicing portion 211. In a region 213 between the main body portions 210 of any adjacent mask sheets 21, a part of the second pixel hole 2130 penetrates only the second splicing portion 212, and a part of the second pixel hole 2130 penetrates both the stacked second splicing portion 212 and the first splicing portion 211.

Because during the evaporation, the upper surface of the second splicing portion 212 is closer to the glass substrate to be evaporated, and because the hole wall of the second pixel hole 2130 has a certain slope, the influence of the side of the second pixel hole 2130 closer to the glass substrate to be evaporated on the evaporation is larger. Therefore, in the present invention, the second pixel hole 2130 at least penetrates through the second splicing part 212, and in order to facilitate processing the second pixel hole 2130, the width of the overlapping region between the first splicing part 211 and the second splicing part 212 is reduced, so that more second pixel holes 2130 only penetrate through the second splicing part, and therefore the width of the second splicing part 212 is set to be greater than the width of the first splicing part 211.

Optionally, as shown in fig. 3b, 4b, and 6b, in any two adjacent mask sheets 21, a distance H is provided between the second spliced portion 212 of one mask sheet 21 and the main body portion 210 of the other mask sheet 21. The pitch H is smaller than a distance L between adjacent two first pixel apertures 2100 in the width direction of the mask sheet 21.

When the webs of mask sheets 21 are stretch-welded to the frame, the distance H between the second spliced portion 212 and the main body portion 210 of the adjacent mask sheet 21 need only be controlled. By controlling the single factor of the distance H, the alignment of two adjacent mask sheets 21 is controlled, the alignment difficulty is reduced, and the lapping precision of the mask sheets 21 is also reduced. And the length of the first splicing part 211 positioned on the lower side of the second splicing part 212 does not influence the evaporation effect, so that the first splicing part 211 and the second splicing part 212 can be aligned more conveniently.

When the pitch H is smaller than the distance L between two first pixel holes 2100, the pitch H does not affect the fabrication of the second pixel holes 2130 located on one side of the pitch H, so that the second pixel holes 2130 can be formed at one time during the fabrication.

Optionally, the pitch H ranges from 10 μm to 500 μm.

The pitch H is in the order of the pixel holes, and when set within the above range, it is convenient to fabricate the first and second pixel holes 2100 and 2130.

Optionally, the frame 20 and the mask 21 are made of metal, and the metal includes simple metal and alloy, wherein the metal alloy may be invar alloy, for example.

An embodiment of the present invention further provides a method for manufacturing a mask 2, and as shown in fig. 2a, fig. 3a, fig. 4a, fig. 5a, and fig. 6a, the mask 2 includes: a plurality of mask sheets 21; the mask sheet 21 comprises a main body portion 210, a first spliced portion 211 and a second spliced portion 212, wherein the first spliced portion 211 and the second spliced portion 212 are located on two sides of the main body portion 210 in the width direction of the mask sheet 21; the body portion 210 is provided with a plurality of first pixel holes 2100.

The sum of the thicknesses of the first splicing part 211 and the second splicing part 212 is equal to the thickness of the main body part 210, the lower surface of the first splicing part 211 is flush with the lower surface of the main body part 210, and the upper surface of the second splicing part 212 is flush with the upper surface of the main body part 210.

As shown in fig. 9a, the method for manufacturing the mask 2 includes:

s1, as shown in fig. 9b and 9c, sequentially screen-welding a plurality of mask sheets 21 to the frame 20, and overlapping the first spliced portion 211 of one mask sheet 21 with the second spliced portion 212 of another mask sheet 21 in any adjacent two mask sheets 21.

For example, as shown in fig. 9d, each mask sheet 21 is stretched and then welded to the frame 20. In the process of stretching the web, the stretching jig is brought into contact with the stretching portion of each mask sheet 21. After all the mask sheets 21 are welded to the frame 20, the stretching portions 214 of all the mask sheets 21 are cut off, and the structure of the cut-off semi-finished mask plate is shown in fig. 9 b.

Illustratively, as shown in fig. 9b and 9c, the width of the first splicing portion 211 is equal to the width of the second splicing portion 212, and the orthographic projection of the second splicing portion 212 of one mask sheet 21 and the orthographic projection of the first splicing portion 211 of the other mask sheet 21 in two adjacent mask sheets 21 in the thickness direction of the mask sheets 21 are completely overlapped.

It should be noted that the relationship between the widths and the overlapping positions of the first splicing portion 211 and the second splicing portion 212 is not limited to the relationship shown in fig. 9c, and otherwise please refer to the relationship between the widths and the overlapping positions of the first splicing portion 211 and the second splicing portion 212 shown in fig. 2a to 6b, which is only illustrated in the relationship shown in fig. 9 c.

S2, as shown in fig. 2b, a plurality of second pixel holes 2130 are formed in the regions 213 between the main body portions 210 of any adjacent mask sheets 21, and all of the first pixel holes 2100 and all of the second pixel holes 2130 are arrayed and uniformly arranged as a whole.

For example, a plurality of second pixel holes 2130 are formed in the regions 213 between the main body portions 210 of any adjacent mask sheets 21 by laser etching.

Since the width of the region 213 between the main bodies 210 of any adjacent mask sheets 21 is small, the time required for processing using a laser beam is short, the processing efficiency is high, and the processing accuracy is high.

In the method for manufacturing the mask sheets 21 according to the embodiment of the present invention, the first spliced portion 211 and the second spliced portion 212 are disposed on two sides of the main body 210 of each mask sheet 21, so that when the mask sheets 21 are net-welded to the frame 20, the first spliced portion 211 and the second spliced portion of the adjacent mask sheets 21 are overlapped; then, second pixel holes 2130 are formed in the regions 213 between the main body portions 210 of any two adjacent mask sheets 21 by means of laser etching. On one hand, the second pixel holes 2130 are processed in a laser etching mode, and each second pixel hole 2130 is formed in one step, so that the processing efficiency is high. On the other hand, by processing the region 213 between the main bodies 210 of any two adjacent mask sheets 21, the requirement for the alignment accuracy of the two adjacent mask sheets 21 is low, and the alignment efficiency of the plurality of mask sheets 21 can be improved. In another aspect, the mode of splicing the plurality of mask sheets 21 can reduce the sagging amount of the mask sheets 21 in the width direction during vapor deposition and enable the mask sheets 21 to be difficult to wrinkle when the mesh is stretched, thereby reducing the probability of occurrence of color mixing defects, ensuring the vapor deposition effect, and simultaneously reducing the maintenance cost of the mask plate 2. Therefore, the mask plate 2 provided by the embodiment of the invention can be prepared into a mask plate with small drooping amount, less possibility of generating wrinkles, good evaporation effect and low production and maintenance cost.

Alternatively, a plurality of second pixel holes 2130 are formed in the region 213 between the main body portions 210 of any adjacent mask sheets 21, and include:

s10, as shown in fig. 10a, the frame 20 to which the mask sheet 21 is welded is placed on the laser processing machine 31, and the mask sheet 21 is brought into close contact with the laser processing machine 31 by the magnetic force generating device 32 located below the laser processing machine 31.

The frame 20 welded with the masking film 21 is placed on the laser processing machine 31 of the laser processing device 3, so that the surface of the second splicing part 212 is in contact with the laser processing machine 31, the magnetic force generating device 32 located below the laser processing machine 31 can generate magnetic force, and the masking film 21 made of metal can be adsorbed on the laser processing machine 31.

S11, as shown in fig. 10b, a plurality of second pixel holes 2130 are formed in the regions 213 between the main bodies 210 of any adjacent mask sheets 21 by the laser emitter 33.

The laser is used for punching, the operation is simple, and the processing efficiency and the processing precision are higher.

Optionally, as shown in fig. 10c, the width of the second splicing portion 212 is greater than the width of the first splicing portion 211.

Placing the frame 20 on the laser processing machine 31 includes:

the frame 20 is turned 180 ° and placed on the laser processing machine 31, so that the second splicing portion 212 contacts with the laser processing machine 31.

Illustratively, the second pixel hole 2130 has a trapezoidal longitudinal cross section. Because the hole walls of the second pixel holes 2130 have a certain slope, and in each second pixel hole 2130, the size of the opening at the end close to the second splicing part 212 is smaller than the size of the opening at the end close to the first splicing part 211, so that the frame 20 is turned by 180 degrees to facilitate the processing of the inclination angle of the hole wall of the second pixel hole 2130. Meanwhile, the second pixel holes 2130 are processed after the frame 20 is turned by 180 degrees, so that burrs which are formed at the edges of the second pixel holes 2130 close to one side of the glass substrate to be vapor-deposited and are formed when the mask plate 2 is vapor-deposited can be reduced, and the risk that the mask plate 2 scratches and scratches the glass substrate to be vapor-deposited is reduced.

Since the second pixel hole 2130 always penetrates through the second splicing portion 212 and may or may not penetrate through the first splicing portion 211, the width of the first splicing portion 211 has little influence on the processing of the second pixel hole 2130, and therefore, the width of the second splicing portion 212 is set to be larger than the width of the first splicing portion 211, so that the overall width of the mask sheet 21 can be reduced without influencing the processing of the second pixel hole 2130, and the production cost of the mask sheet 21 is reduced.

It should be noted that, when the second pixel hole 2130 is processed, the half-sheet mask plate may not be turned over, but at this time, the positional relationship between the laser processing device 3 and the half-sheet mask plate is as shown in fig. 10d, that is, regardless of the position between the laser processing device 3 and the half-sheet mask plate, the laser emitter 33 may always process the second pixel hole 2130 from the side where the first splicing portion 211 is located (the side where the mask plate 2 is close to the glass substrate to be vapor-deposited during vapor deposition).

It should be noted that, in the structure shown in fig. 10a to 10d, when the second spliced portion 212 of the rightmost mask sheet 21 is connected to the frame 20, the second spliced portion 212 needs to be connected to the frame 20 through the connecting portion 5 because there is a gap between the second spliced portion 212 and the frame 20. For example, the connecting portion 5 may be, for example, a solder, or be integrally formed with the second splicing portion 212, or be integrally formed with the frame 20, which is not limited herein.

Alternatively, forming the mask sheet 21 includes:

as shown in fig. 11a, the mask sheet body 4 is divided into three regions, namely, a middle region 41 and edge regions 42 respectively located at two sides of the middle region 41.

As shown in fig. 11b, the edge region 42 of the mask body 4 is etched by half etching to form a first splicing part 211 and a second splicing part 212 respectively; the mask sheet body 4 located in the intermediate region 41 is a main body portion 210. The body portion 210 is provided with a plurality of first pixel holes 2100 arranged in an array.

Illustratively, the half-tone mask 2 may be implemented by an ashing process.

The embodiment of the present invention further provides a mask sheet 21, as shown in fig. 11b, including a main body portion 210, a first splicing portion 211 and a second splicing portion 212, where the first splicing portion 211 and the second splicing portion 212 are located at two sides of the main body portion 210 along a width direction of the mask sheet 21; the body portion 210 is provided with a plurality of first pixel holes 2100.

As shown in FIG. 11c, the sum of the thicknesses of the first and

second splices

211, 212 is equal to the thickness of the body portion 210; the lower surface of the first splicing portion 211 is flush with the lower surface of the main body portion 210, and the upper surface of the second splicing portion 212 is flush with the upper surface of the main body portion 210.

It can be understood that, in the embodiment of the present invention, for each mask sheet 21, when the mask plate 2 is not assembled, the thicknesses of the portions of the regions where the first splicing portion 211 and the second splicing portion 212 are located are consistent, and no hole exists.

The mask 21 can be used to manufacture the mask 2, and thus has the same beneficial effects as the mask 2, and thus, the description thereof is omitted.

Optionally, the thickness of the first splicing portion 211 is equal to the thickness of the second splicing portion 212. It is convenient to form the first and

second splices

211 and 212, respectively, by half-engraving.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A mask sheet is characterized by comprising a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body part is provided with a plurality of first pixel holes;

2. The mask sheet according to claim 1, wherein the thickness of the first splicing portion is equal to the thickness of the second splicing portion.

3. A mask plate is characterized by comprising a frame and a plurality of mask sheets arranged on the frame in a spanning mode;

the mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body part is provided with a plurality of first pixel holes;

the sum of the thicknesses of the first splicing part and the second splicing part is equal to the thickness of the main body part; the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part; any adjacent mask sheets, wherein the first splicing portion of one of the mask sheets overlaps the second splicing portion of the other mask sheet;

4. A mask according to claim 3, wherein the width of the second splicing portion is greater than the width of the first splicing portion;

5. A mask according to claim 3 or 4, wherein in any two adjacent mask sheets, the second spliced portion of one mask sheet is spaced from the main body portion of the other mask sheet;

6. A mask according to claim 5, wherein the pitch is in the range of 10 μm to 500 μm.

7. A preparation method of a mask plate is characterized in that the mask plate comprises: a plurality of mask sheets; the mask sheet comprises a main body part, a first splicing part and a second splicing part, wherein the first splicing part and the second splicing part are positioned on two sides of the main body part along the width direction of the mask sheet; the main body part is provided with a plurality of first pixel holes;

the sum of the thicknesses of the first splicing part and the second splicing part is equal to the thickness of the main body part, the lower surface of the first splicing part is flush with the lower surface of the main body part, and the upper surface of the second splicing part is flush with the upper surface of the main body part;

the preparation method of the mask plate comprises the following steps:

sequentially screen-welding a plurality of mask sheets on a frame, and overlapping the first spliced portion of one of the mask sheets with the second spliced portion of the other of any two adjacent mask sheets;

8. A method of manufacturing a mask according to claim 7, wherein forming a plurality of second pixel holes in regions between the main body portions of any adjacent mask pieces includes:

placing the frame on a laser processing machine table, and enabling the mask sheet to be tightly attached to the laser processing machine table through a magnetic force generating device located below the laser processing machine table;

9. A preparation method of a mask according to claim 8, wherein the width of the second splicing part is larger than that of the first splicing part;

placing the frame on a laser processing machine table, including:

10. A method of manufacturing a mask according to claim 7, wherein forming the mask film comprises:

dividing the mask sheet body into three regions, namely a middle region and edge regions respectively positioned at two sides of the middle region;