CN113643613A

CN113643613A - Display panel, manufacturing method thereof and splicing display device

Info

Publication number: CN113643613A
Application number: CN202110912525.2A
Authority: CN
Inventors: 王恺君
Original assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2021-08-10
Filing date: 2021-08-10
Publication date: 2021-11-12

Abstract

The application discloses a manufacturing method of a display panel and the display panel, wherein the manufacturing method of the display panel comprises the following steps: providing a substrate, wherein the substrate is provided with a first surface and a second surface opposite to the first surface, the first surface is provided with a display lead area, and the second surface is provided with a binding area; coating a conductive material on a substrate, wherein the conductive material covers at least one part of the side edge of the substrate, and covers part of the display lead area and part of the binding area; and printing the conductive material by using a 3D printing technology to form a plurality of wires, wherein each wire respectively conducts the display lead area and the binding area. Through setting up the conducting material district in advance, draw the wire 3D model in the computer, design the linewidth, the line thickness of wire, position isoparametric, make the wire minimum at the size of panel edge, carry out the 3D of wire again and print, make the frame width of panel minimum, realize extremely narrow frame even no frame.

Description

Display panel, manufacturing method thereof and splicing display device

Technical Field

The application relates to the technical field of display, in particular to a display panel, a manufacturing method thereof and a splicing display device.

Background

With the higher requirements of people on display devices, the frame of the display screen is smaller and smaller, so that better visual experience is obtained. Narrow borders are usually achieved by reducing the border around the display area through design and material optimization, but the adjustable border size is limited in this way. The flexible circuit board is generally bound on the side frame of the display panel, the display panel is connected with the control component in a conduction mode, the flexible circuit board has certain width and thickness, and even if the flexible circuit board is bent, the frame is difficult to further narrow.

Disclosure of Invention

The invention aims to provide a manufacturing method of a display panel, the display panel and a splicing display device, so that the display panel can achieve extremely narrow frames and even no frames.

In order to achieve the above object, the present invention provides a method for manufacturing a display panel, comprising the steps of:

providing a substrate, wherein the substrate is provided with a first surface and a second surface opposite to the first surface, the first surface is provided with a display lead area, and the second surface is provided with a binding area;

coating a conductive material on a substrate, wherein the conductive material covers at least one part of the side edge of the substrate, and covers part of the display lead area and part of the binding area;

and printing the conductive material by using a 3D printing technology to form a plurality of wires, wherein each wire respectively conducts the display lead area and the binding area.

Further, in the step of printing the conductive material by using a 3D printing technology to form a plurality of conductive lines, the step of printing the conductive material by using a two-photon polymerization laser writing method specifically includes performing 3D printing to form a plurality of conductive lines.

Furthermore, the laser used in the two-photon polymerization laser writing mode is a femtosecond laser.

Further, in the step of printing the conductive material to form a plurality of conductive lines by using a 3D printing technology, the method specifically includes the following steps:

scanning and solidifying the conductive material line by using laser;

and cleaning the conductive material which is not scanned and solidified in the conductive material by using a cleaning liquid, and leaving the conductive wire.

Further, the conductive material includes: metal nanoparticles with a particle size of 20-50 nm; in the step of printing the conductive material to form a plurality of wires by using a 3D printing technology, the method further includes: and firing the conductive routing to form the lead.

Further, the conductive material includes: a UV type photoinitiator.

Further, the conductive material further comprises: monofunctional carboxylic mesogens, which are used to form hydrogen bonds, act as supramolecular cross-linkers during laser polymerization.

Further, the step of providing the substrate specifically includes the following steps:

providing a large plate;

forming a plurality of display regions and display lead regions on a first surface of the large plate;

coating a light resistance protective layer on the display area;

forming a plurality of bonding regions on the second surface of the large plate, each bonding region corresponding to each display lead region; and

cutting the large board into a plurality of the substrates, each of the substrates having one of the display regions, at least one of the display lead regions, and at least one of the bonding regions thereon.

In order to achieve the above object, the present application further provides a display panel, which is prepared by the above method for preparing a display panel, and comprises:

the display device comprises a display area and a frame area, wherein the display lead area is positioned in the frame area, and the width of the frame area is less than 100 mu m.

In order to achieve the above object, the present application further provides a tiled display device, which includes a plurality of the above display panels tiled with each other.

The conductive material is printed to form a plurality of wires by presetting the conductive material and then conducting 3D printing on the wires, so that the width of a frame of the panel is minimum, and an extremely narrow frame or even no frame is realized.

Drawings

The technical solution and other advantages of the present application will become apparent from the detailed description of the embodiments of the present application with reference to the accompanying drawings.

Fig. 1 is a structural diagram of a first surface of a display panel according to an embodiment of the present application.

Fig. 2 is a structural diagram of a second surface of a display panel provided in an embodiment of the present application.

Fig. 3 is a structural diagram of a substrate cut into a plurality of panels according to an embodiment of the present application.

Fig. 4 is a schematic cross-sectional view illustrating a conductive material coated on a substrate according to an embodiment of the disclosure.

Fig. 5 is a flowchart of a method for manufacturing a display panel according to an embodiment of the present disclosure;

fig. 6 is a flowchart illustrating specific steps included in S100 in the method for manufacturing a display panel according to the embodiment of the present disclosure.

Fig. 7 is a flowchart illustrating a specific step included in S130 in the method for manufacturing a display panel according to the embodiment of the present application.

The components of the drawings are identified as follows:

100. a large plate; 110. a first surface;

120. a second surface; 130. a substrate;

200. a display area; 210. a display lead area;

300. a binding region; 400. a conductive material;

410. a first material region; 420. a second material region.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or assembly so referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

The embodiment of the present application provides a method for manufacturing a display panel, so that the display panel can achieve an extremely narrow frame or no frame, as shown in fig. 5 to 7, the method includes the following steps:

s100, providing a substrate 130, wherein the substrate 130 has a first surface 110 and a second surface 120 opposite to the first surface 110, the first surface 110 is formed with a display lead region 210, and the second surface 120 is formed with a bonding region 300; as shown in fig. 1 and 2, the substrate 130 has a first surface 110 and a second surface 120 opposite to the first surface 110; the substrate 130 is a glass substrate 130, and the first surface 110 and the second surface 120 of the substrate 130 are two surfaces of the substrate 130 in the thickness direction.

The positions of the display area 200 and the binding area 300 may be interchanged. Firstly, forming a display area 200 on the first surface 110, and when forming the display area 200, specifically: a thin film transistor, a light emitting device, and an encapsulation thin film layer are sequentially formed on the first surface 110 of the substrate 130. Then, a display lead region 210 is formed, and the display lead region 210 is connected to the display region 200, electrically connected to the display region 200, and led out. In forming the bonding region 300, the substrate 130 is turned over, and the bonding region 300 is formed on the other surface of the substrate 130, the bonding region 300 being positioned opposite to the display lead region 210. When the bonding region 300 is formed, specifically: a first metal layer, a first insulating layer, a second metal layer, a second insulating layer, and a transparent electrode layer are sequentially formed on the second surface 120 of the substrate 130. The first insulating layer and the second insulating layer are both subjected to hole opening treatment, so that the transparent electrode layer is respectively lapped with the first metal layer and the second metal layer in different areas. It is noted that the lead regions 210 and the bonding regions 300 are shown near the edge of the substrate 130 to facilitate wire bonding.

In one embodiment, step S100 specifically includes the following steps:

s101, providing a large plate 100;

s102, forming a plurality of display areas 200 and display lead areas 210 on the first surface 110 of the large plate 100; as shown in fig. 3, the large plate 100 is a large glass plate and can be divided into a plurality of substrates 130, and when the display lead area 210 is manufactured, all the display areas 200 and the display lead areas 210 on the substrates 130 can be manufactured at the same time, so as to improve the manufacturing efficiency of the display areas 200 and the display lead areas 210.

S103, coating a photoresist protective layer above the display area 200; the photoresist protective layer has a wide selection range, can be a negative photoresist or a positive photoresist, and can adopt one of the conventional positive/negative photoresists on the market. Since the substrate 130 needs to be turned over when the bonding region 300 is manufactured, the photoresist protective layer can protect the display region 200 and the display lead region 210.

S104, forming a plurality of bonding regions 300 on the second surface 120 of the large board 100, and referring to fig. 1 to 3, each bonding region 300 corresponds to each display lead region 210. The substrate 130 is turned over, and a plurality of bonding regions 300 are formed on the second surface 120, wherein each bonding region 300 corresponds to each display lead region 210, and the corresponding bonding region 300 and the display lead region 210 are located in the same substrate 130.

After step S104, the method further includes the following steps:

s105, cutting the large panel 100 into a plurality of substrates 130, each substrate 130 having one display area 200, at least one display lead area 210, and at least one bonding area 300 thereon.

The large board 100 is cut according to the size of the substrate 130, each substrate 130 has a display lead area 210 and a bonding area 300, and the bonding area 300 and the display lead area 210 are located at the edge of the substrate 130, which facilitates the fabrication of the subsequent conductive wires. After the fabrication of the bonding region 300 is completed, the photoresist protection layer may be removed, in this embodiment, the photoresist protection layer is stripped by a stripping liquid, where the stripping liquid may be a stripping liquid corresponding to the selected photoresist, such as a conventional negative photoresist, and a KOH stripping liquid is used for stripping, but in other embodiments, the stripping liquid may be other, and is not specifically limited in this embodiment.

S120, coating a conductive material on the substrate 130, wherein the conductive material covers at least a portion of a side of the substrate 130, and covers a portion of the display lead region 210 and a portion of the bonding region 300. As shown in fig. 1, 2 and 4, the conductive material 400 covers at least a portion of the side of the substrate 130, and partially covers the display lead region 210 and the bonding region 300. A conductive material 400 is coated on each substrate 130 and sequentially covers the display lead area 210, the bonding area 300, and the side of the substrate 130, wherein the display lead area 210 and the bonding area 300 are adjacent to one side of the substrate 130. The conductive material 400 is arranged in the shape of "Contraband". In this embodiment, the conductive material 400 partially covers the display lead area 210 and the bonding area 300, so that the conductive material can be completely connected to the traces of the display lead area 210 and the traces of the bonding area 300, thereby facilitating the fabrication of the subsequent wires.

S130, printing a plurality of wires on the conductive material 400 by using a 3D printing technique, wherein each wire respectively connects the display lead region and the bonding region 300. The conductive material of the conductive material 400 can be directly converted into a conductive wire by using a 3D printing technology, and the position, the line width, the line length and the line thickness of the conductive wire are determined by computer calculation, so that the conductive wire is thinnest at the substrate 130 or at the part of the side edge of the substrate 130, the side edge thickness is reduced to the greatest extent, and the display panel with an extremely narrow frame or even no frame is obtained.

In step S130, the method specifically includes performing 3D printing to form a plurality of wires by using a two-photon polymerization laser writing method, where a laser used in the two-photon polymerization laser writing method is a femtosecond laser. The conductive material is a conductive material which can be subjected to 3D printing. The conductive material comprises metal nano-particles, oligomers, monomers, carboxylic acid mesomorphic substances and a photoinitiator. Wherein the content of the metal nano particles is 40-70 wt%, the content of the oligomer is 10-20 wt%, the content of the monomer is 10-20 wt%, the content of the carboxylic acid mesogen is 5-10 wt%, and the content of the photoinitiator is 2-5 wt%.

The metal nanoparticles can be gold nanoparticles, silver nanoparticles, copper nanoparticles, etc., and have a particle size of 20-50 nm.

The oligomer is one or more of epoxy acrylate, urethane acrylate, polyether acrylate, polyester acrylate, acrylic resin, etc., and the monomer is one or more of monofunctional (IBOA, IBOMA, HEMA, etc.), difunctional (TPGDA, HDDA, DEGDA, NPGDA, etc.), trifunctional, and multifunctional (TMPTA, PETA, etc.).

The photoinitiator is a UV initiator, such as photoinitiator 819, photoinitiator 184, photoinitiator 651 and the like, and one or more of them can be used, preferably, the photoinitiator 819 and the phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide (Irgacure819) have a molecular formula of C26H27O3P and have the following structural formula:

the UV type photoinitiator can directly initiate two-photon photopolymerization, so that the polymer monomer can be completely crosslinked and cured within a short time by laser scanning.

The carboxylic acid mesogen is monofunctional carboxylic acid mesogen, molecules functionalized by the carboxylic acid can form hydrogen bonds, and the hydrogen bonds serve as supramolecular cross-linking agents in the laser polymerization process, so that the nm-level printing precision is realized, and the precision of the conductive material is ensured. The mesogenic carboxylic acid can be one or more of 4- ((6- (acryloyloxy) hexyl) oxy) benzoic acid, 4- ((6- (acryloyloxy) hexyl) oxy) -2-methylbenzoic acid, 4- ((5- (acryloyloxy) pentyl) oxy) benzoic acid, and 4- (3- (acryloyloxypropoxy)) benzoic acid, and the molecular structural formulas are respectively as follows:

during laser polymerization, the photoinitiator initiates monomer polymerization, the carboxylic acid mesogen generates supermolecule cross-linking reaction, and the curing is completed in a short time. After curing was complete, washing in isopropanol was carried out to dissolve the unpolymerized material. At the moment, heating sintering is needed, the sintering temperature is 100-400 ℃, the heating sintering enables metal nano particles in the formed conducting wire to be connected in a sintering mode, a conducting wire with low resistivity is obtained, and the higher the sintering temperature is, the lower the resistivity is, and the metal nano particles can be selected by combining actual requirements.

It is further noted that the conductive material 400 includes:

a first material region 410 covering the display lead region 210, the first material region 410 having a length direction parallel to a side of the substrate 130 and a width direction perpendicular to the length direction;

a second material region 420 covering the bonding region 300, the second material region 420 having a length direction parallel to the side of the substrate 130 and a width direction perpendicular to the length direction; the first material region 410 and the second material region 420 have the same width direction. The direction of the arrows in fig. 4 is the width direction of the first material region 410 and the second material region 420.

The first material region 410 and the second material region 420 have a length in the width direction (in the direction of the arrow) of 50-100 um. In this embodiment, the first material region 410 completely covers the display lead region 210, and the second material region 420 partially covers the bonding region 300, so as to ensure that the outgoing trace that can cover the bonding region 300 can be connected to the bonding region 300. The first material region 410 and the second material region 420 having the width range can ensure the uniformity of the conductive material spreading without causing a waste of material.

Wherein in step 130, the method specifically comprises the following steps:

s131, drawing a 3D model of wires, wherein each wire is connected between the display lead area 210 and the binding area 300; in this embodiment, a 3D model of a wire is drawn in computer CAD software, where the display lead area 210 and the binding area 300 both have connection positions, the connection positions may be connection points or connection lines such as lead-out wires, and the wire is connected between the lead-out wires of the display lead area 210 and the connection positions of the binding area 300, so as to achieve electrical conduction between the binding area 300 and the wire routing area. The drawn 3D model of the conductive line can specify various parameters of the conductive line, so that the thickness of the portion of the conductive line located at the side of the substrate 130 is minimized to achieve the effect of narrowest frame of the substrate 130.

And S132, performing 3D printing on the conductive material 400 according to the 3D model of the conductive wire to form a plurality of conductive wires. After designing the conductive line, the conductive material 400 is 3D printed according to the 3D model of the conductive line, so that the conductive material of the conductive material 400 forms a predetermined conductive line.

In step S131, the method specifically includes the following steps:

s1311, drawing a path of the wire according to the outgoing trace on the display lead area 210 and the outgoing trace on the binding area 300; the wires are connected between the outgoing lines of the display lead area 210 and the outgoing lines of the bonding area 300, so that the wires can be electrically connected between the display lead area 210 and the bonding area 300. In addition, the side of the lead wire attaching substrate 130 is disposed to reduce the frame width of the substrate 130 as much as possible.

S1312, designing the line width, line length, line thickness and position of the conducting wire, and combining the path of the conducting wire to obtain a 3D model of the conducting wire. According to the thickness and range of the conductive material 400 and the standard that can ensure the connection effect, the line width, line length, line thickness and position of the conductive line are designed, and during the design, the line width and line thickness of the conductive line are kept as small as possible, so as to obtain the conductive line parameters of the scheme that the frame of the substrate 130 is the minimum.

In step S130, the method further includes the following steps:

s1301, scanning and curing the conductive material 400 by using laser; the two-photon polymerization writing technology is preferably selected in the 3D printing technology, the technology is matched with the provided conductive materials, the nanometer-level precision can be achieved, the wiring position can be precisely controlled to be in butt joint with the display lead area 210 to lead out the wiring and the binding area 300 to lead out the wiring in the wire position, the phenomenon that the wire is broken or short-circuited when the substrate 130 with the higher pixels is manufactured is prevented, and meanwhile, the line width, the line distance and the line thickness can be precisely controlled, so that the wiring resistance is controlled.

S1302, cleaning the unscanned conductive material in the conductive material 400 by using a cleaning liquid, and leaving a conductive routing; the cleaning liquid can clean the part of the conductive material which is not scanned by the laser, so that the part of the conductive material which is scanned by the laser is left to form the conductive routing.

And S1303, burning the conductive wire to form the lead. And (4) carrying out high-temperature firing on the left conductive wires to enable the conductive wires to form wires.

After step S132, the method further includes the following steps:

s133, coating protective glue on the lead; the protective adhesive may be a UV curable type or a thermosetting type, and is not particularly limited in this embodiment. The coating mode can adopt a side printing mode, the whole conductive wiring area needs to be covered to play a role in protection, the thickness of the protective adhesive is 5-15um, and if the thickness is less than 5um, the protective adhesive is too thin, and the protection effect is weaker; if the thickness is larger than 15um, the protective adhesive is too thick, and the frame width of the substrate 130 is increased.

S134, finishing the binding process of the chip on film COF and the printed circuit board PCB in the binding area 300.

Before step S120, the following steps are also included:

and S115, edging the side edge of the substrate 130 close to the display lead area 210 and the binding area 300. Specifically, the side edges of the substrate 130 close to the display lead area 210 and the binding area 300 are edge-ground, so that the edge edges of the side edges are smoothly ground, and the subsequently formed wire routing is prevented from being damaged by sharp edges. Preferably, the upper edge and the lower edge of the glass are directly ground into smaller R corners, and the side edge parts of the glass are ground smoothly, so that the frame is further reduced. In other embodiments, the upper and lower edges of the glass may also be chamfered, and this embodiment is not particularly limited.

According to the manufacturing method of the display panel, the conducting material 400 can be preset, the 3D model of the conducting wire can be drawn in the computer, parameters such as the line width, the line thickness and the position of the conducting wire are designed, the size of the conducting wire at the edge of the substrate 130 is the minimum, then 3D printing of the conducting wire is carried out, the width of the frame of the substrate 130 is the minimum, and the extremely narrow frame or even no frame is achieved.

The application also discloses a display panel which is manufactured by the display panel manufacturing method, and the display panel is provided with a display area and a frame area. The width of the frame area is positively correlated with the width of the conducting wire at the side of the display area. The conducting wire is formed by 3D printing, when a conducting wire 3D model is drawn, parameters such as line width, line thickness and position of the conducting wire are designed and adjusted, so that the size of the conducting wire at the edge of the display area is minimum, the width of the frame area is minimum and can be smaller than 100 mu m, and extremely narrow frames or even no frames are realized.

The application also provides a tiled display device, including a plurality of display panel splice each other as before, among the tiled display device, the gap between the display panel of mutual concatenation is minimum to promote tiled display device's display effect.

The above detailed description is given to the manufacturing method of the display panel, and the tiled display device provided in the embodiment of the present application, and a specific example is applied in the present application to explain the principle and the implementation manner of the present application, and the description of the above embodiment is only used to help understanding the technical scheme and the core idea of the present application; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. A manufacturing method of a display panel is characterized by comprising the following steps:

coating a conductive material on a substrate, wherein the conductive material covers at least one part of the side edge of the substrate, and covers part of the display lead area and part of the binding area; and

2. The method for manufacturing the display panel according to claim 1, wherein in the step of printing the conductive material to form the plurality of conductive lines by using a 3D printing technology, the step of printing the conductive material to form the plurality of conductive lines specifically comprises performing 3D printing to form the plurality of conductive lines by using a two-photon polymerization laser writing method.

3. The method of claim 2, wherein the laser used in the two-photon polymerization laser writing method is a femtosecond laser.

4. The method for manufacturing the display panel according to claim 2, wherein in the step of printing the conductive material by using a 3D printing technology to form the plurality of conductive lines, the method specifically comprises the following steps:

scanning and solidifying the conductive material line by using laser;

5. The method for manufacturing a display panel according to claim 4, wherein the conductive material comprises: metal nanoparticles with a particle size of 20-50 nm; in the step of printing the conductive material to form a plurality of wires by using a 3D printing technology, the method further includes: and firing the conductive routing to form the lead.

6. The method for manufacturing a display panel according to claim 2, wherein the conductive material comprises: a UV type photoinitiator.

7. The method for manufacturing a display panel according to claim 6, wherein the conductive material further comprises: monofunctional carboxylic mesogens, which are used to form hydrogen bonds, act as supramolecular cross-linkers during laser polymerization.

8. The method for manufacturing a display panel according to claim 1, wherein the step of providing the substrate specifically includes the steps of:

providing a large plate;

coating a light resistance protective layer on the display area;

9. A display panel produced by the method for producing a display panel according to any one of claims 1 to 8, comprising:

10. A tiled display arrangement comprising a plurality of display panels according to claim 9 tiled together.