CN114327144A

CN114327144A - Touch control assembly, touch control display panel and preparation method

Info

Publication number: CN114327144A
Application number: CN202111654769.1A
Authority: CN
Inventors: 叶慧敏; 党鹏乐; 郑红
Original assignee: Guangzhou Guoxian Technology Co Ltd
Current assignee: Guangzhou Guoxian Technology Co Ltd
Priority date: 2021-12-30
Filing date: 2021-12-30
Publication date: 2022-04-12

Abstract

The application discloses a touch control assembly, a touch control display panel and a preparation method, wherein the touch control assembly comprises a touch control electrode and a touch control lead, and the touch control electrode comprises a touch control area and a lap joint area; the touch lead comprises a flexible film and metal wiring arranged on the flexible film, the touch lead is externally hung on the touch electrode, and the first end of the touch lead is electrically connected with the touch electrode in the lap joint area through a conductive connecting piece. Through the mode, the circuit stability of the touch lead can be improved on the basis of realizing the narrow frame, and the wiring cost is reduced.

Description

Touch control assembly, touch control display panel and preparation method

Technical Field

The present disclosure relates to the field of semiconductor display technologies, and in particular, to a touch module, a touch display panel and a manufacturing method thereof.

Background

The integrated touch display is widely accepted and used by people, and for example, a smart phone, a tablet computer and the like all use a touch display technology. With the further development of display technologies, people have more and more requirements on touch display devices, such as pursuing thinner and narrower frames. Metal wiring is required around the touch display panel, and the requirement on line width/line distance is met; when the frame narrows, the space of the frame cannot meet the requirement of the width of the wire, and in this time, some limit process requirements exist, which often causes the undesirable increase of products and the increase of product price.

Disclosure of Invention

The technical problem mainly solved by the application is to provide a touch component, a touch display panel and a preparation method, which can improve the line stability of a touch lead on the basis of realizing a narrow frame and reduce the wiring cost.

In order to solve the technical problem, the application adopts a technical scheme that: providing a touch control assembly, wherein the touch control assembly comprises a touch control electrode and a touch control lead wire, and the touch control electrode comprises a touch control area and a lap joint area; the touch lead comprises a flexible film and metal wiring arranged on the flexible film, the touch lead is externally hung on the touch electrode, and the first end of the touch lead is electrically connected with the touch electrode in the lap joint area through a conductive connecting piece.

The touch lead is also provided with a protective layer, the protective layer is arranged on one side of the metal wiring, which is far away from the flexible film, and the protective layer does not completely cover the metal wiring.

Wherein the flexible film comprises one or more of a film and a polyethylene terephthalate film.

Wherein, the conductive connecting piece comprises a conductive double-sided adhesive tape.

And the second end of the touch lead is connected with the flexible circuit board.

The metal wire comprises a metal nanowire.

Wherein the diameter of the metal nanowire is 20-100 nm, and the length of the metal nanowire is 20-100 μm.

Wherein the thickness of the flexible film is 50-150 μm.

Wherein the width of the metal trace is 5-20 μm.

Wherein the distance between two adjacent metal wires is 5-20 μm

Wherein the width of the lap joint zone is 0.5-10 μm.

In order to solve the above technical problem, another technical solution adopted by the present application is: a touch display panel is provided. The touch control device comprises a display substrate and the touch control assembly, wherein the touch control assembly is arranged on the display substrate, and the touch control lead is bent to the backlight side of the display substrate.

In order to solve the above technical problem, another technical solution adopted by the present application is: the preparation method of the touch control assembly comprises the steps of providing a flexible film, and forming metal wiring on the flexible film to obtain a touch control lead structure; and electrically connecting the touch lead with the touch electrode positioned in the lap joint area through the conductive connecting piece to obtain the touch assembly.

The beneficial effect of this application is: different from the situation in the prior art, the touch control assembly provided by the application is provided with the touch control lead wire externally hung on the film layer where the touch control electrode is located, and is electrically connected with the touch control electrode located in the lap joint area through the conductive connecting piece. Through this kind of mode, only need reserve the space that electrically conductive connecting piece connects on the touch-control electrode rete can, as long as can realize in the space that touch-control lead wire and touch-control electrode be just enough, no longer need set up the space of touch-control lead wire, can narrow touch-control display panel's frame region. Meanwhile, the wiring space of the touch lead can be enlarged, and the wiring cost is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a touch device according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a touch lead according to an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of a touch device according to another embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a touch display panel according to an embodiment of the present disclosure.

Detailed Description

In order to make the purpose, technical solution and effect of the present application clearer and clearer, the present application is further described in detail below with reference to the accompanying drawings and examples.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a touch device according to an embodiment of the present disclosure. In this embodiment, the touch device 100 includes a touch electrode layer 10 and a touch lead 20. The touch electrode layer 10 includes a touch region 110 and a landing region 120. The touch electrode is used for responding to a touch signal so as to realize touch operation. Specifically, signals may be input and output to the touch electrodes through the touch leads 20 connected to the touch electrodes.

Generally, the touch lead 20 is disposed on the same layer as the touch electrode layer 10 and is overlapped with the touch electrode located in the overlapping region 120. However, as the frame of the touch display panel is narrowed, the installation space of the touch lead 20 is compressed, so that the touch display panel is prone to product defects caused by abnormal circuit, and the requirement for the wiring process is increased, which increases the manufacturing cost of the touch display panel. Based on this, this application provides a new wiring design scheme, joins externally touch-control lead wire 20 in touch-control electrode layer 10 setting, and through this kind of mode, on the touch-control subassembly only need reserve the space that electrically conductive connecting piece connects can, as long as can realize in the space touch-control lead wire and touch-control electrode be just enough, no longer need set up the space of touch-control lead wire, can narrow down touch-control display panel's frame region. In other words, current peripheral circuit district includes overlap joint district and touch-control lead wire district, and the mixture is provided with touch-control electrode and touch-control lead wire in the overlap joint district, and touch-control lead wire district is provided with the touch-control lead wire of predetermined overall arrangement, and the scheme that this application provided, peripheral circuit district can only include the overlap joint district, has hung touch-control lead wire district outward. Meanwhile, the external hanging space is large, the wiring space of the touch lead 20 can be enlarged, the requirement on the wiring process is reduced, and the manufacturing cost is further reduced.

Specifically, in the present application, the touch lead 20 is externally connected to the touch electrode layer 10 and electrically connected to the touch electrode located in the lap joint region 120 through the conductive connecting member 30. The external hanging on the touch electrode layer 10 means that the touch lead 20 and the touch electrode layer 10 are two independent structures, which can be independent from each other, and are electrically connected through the conductive connecting member 30.

In an embodiment, the touch lead 20 provided in the present application includes a flexible film and metal traces disposed on the flexible film, so that the touch lead 20 can be flexibly folded, thereby saving the occupied space in the touch display panel. Specifically, the touch lead 20 may be made into a flexible film layer, one end of which is electrically connected to the touch electrode layer 10, and the other end of which can be freely folded and accommodated on the back of the touch display panel, so as to reduce the increase in volume/area of the touch display panel due to the increase in layout space of the touch lead 20, and further meet the design concept of being lighter, thinner and narrower in frame of the touch display panel, so that the final product can be thinner and narrower in frame. Or, the other end of the touch lead 20 is a free end, and the specific shape and position of the free end of the touch lead are not limited in the present application, and when the touch display device is assembled, the touch lead 20 only needs to be accommodated in the casing of the touch display device, and the accommodating position can be adapted to the arrangement according to the spatial layout in the casing of the touch display device.

Referring to fig. 2, fig. 2 is a schematic structural diagram of a touch lead according to an embodiment of the present disclosure. In this embodiment, the touch lead 20 includes a flexible film 21 and a metal trace 22 disposed on the flexible film 21.

The flexible film 21 includes at least one flexible layer. The flexible layer may be a film layer formed of a resin, an organic polymer material, or the like having flexibility. Such as one or more of polyethylene terephthalate (PET) film, film board, Polymethylmethacrylate (PMMA), polyethylene naphthalate (PBN), polycarbonate resin, Polyimide (PI) substrate, polypropylene (PP), Polystyrene (PS), Acrylonitrile Butadiene Styrene (ABS), polyvinyl chloride (PVC), Polyethylene (PE), Polytetrafluoroethylene (PTFE), cyclic olefin copolymer (COP, Arton). Through choosing for use the flexible film, can realize the folding to touch-control lead wire 20 on the one hand, on the other hand can also play certain support guard action to the metal wiring, makes it difficult fracture. In addition, the flexible film is preferably made of a material having good water and gas barrier properties, and can protect the metal wiring.

In other embodiments, the flexible film 21 may also be a combination of multiple film layers. Such as an insulating layer, a metal layer, or a sandwich structure of insulating layers, the middle metal layer provides a certain supporting function to support the metal trace 22, and the metal layer should have a certain flexibility to realize flexible folding. The insulating layer may be an inorganic layer or an organic layer, but the thicknesses of the metal layer and the insulating layer should be as small as possible to provide sufficient flexibility to the flexible film 21 and reduce the total thickness of the flexible film 21.

In one embodiment, the metal traces 22 are disposed on the flexible film 21. The metal layer, such as a copper layer, may be deposited on the entire surface of the flexible film 21, and then etched to obtain the metal trace 22 structure. The metal trace 22 may be disposed in a single layer, or may be disposed in multiple layers, for example, two metal layers may be disposed, and the metal layers are insulated from each other. The plurality of metal traces may be arranged in an array, such as a plurality of metal lines extending in the same direction.

In another embodiment, the metal traces 22 are preferably made using flexible wires to enable the touch leads to be folded. The metal traces 22 can be fabricated using, for example, metal nanowires. Metal nanowires, such as silver nanowires (silver nanowires), gold nanowires (gold nano-wires), or copper nanowires (copper nano-wires); more specifically, as used herein, "metal nano-wires" is a collective term referring to a collection of metal wires comprising a plurality of elemental metals, metal alloys or metal compounds (including metal oxides), wherein the number of metal nanowires contained therein does not affect the scope of the claimed invention; and at least one cross-sectional dimension (i.e., cross-sectional diameter) of the single metal nanowire is less than about 500nm, preferably less than about 100nm, and more preferably less than about 50 nm; the metal nanostructures referred to herein as "wires" have a high aspect ratio, such as between about 10 and 100,000, and more particularly, the metal nanowires may have an aspect ratio (length: diameter of cross section) of greater than about 10, preferably greater than about 50, and more preferably greater than about 100.

The metal nanowires may have an average diameter of about 20 to 100nm, an average length of about 20 to 100 microns, preferably an average diameter of about 20 to 70 nm, and an average length of about 20 to 70 microns (i.e., an aspect ratio of 1000).

With reference to fig. 2, the touch lead further includes a protection layer 23. The protection layer 23 is disposed on a side of the metal trace 22 away from the flexible film 21, and is used for protecting the metal trace 22 and playing a role in insulation. That is, the flexible film 21 and the protective layer 23 are located on both sides of the metal trace 22, so that the metal trace 22 can be protected from being insulated from other components, and the metal trace 22 can be protected from being easily broken.

The protective layer 23 does not completely cover the metal trace 22, and specifically, at least does not cover both ends of the metal trace 22, so that the exposed metal trace 22 is used for electrical connection. As shown in fig. 2, the touch lead 20 includes a circuit area 210 and a connection area 220, and the metal trace 22 located in the connection area 220 is connected to the conductive connector 30 and further electrically connected to other components.

In one embodiment, the thickness of the flexible film may be 50 to 150 μm to sufficiently support the metal traces. In the embodiment, the touch lead is arranged as an external hanging structure, so that a larger wiring design space can be provided, the line width and the line distance of metal wiring are not required to be infinitely reduced by a limit process, and the wiring cost is reduced. For example, a silk-screen process can be used to manufacture the metal traces, and the width of the metal traces can be 5-20 μm; the distance between two adjacent metal lines can be 5-20 μm. In other embodiments, also can use the yellow light technology to make metal and walk the line, and similarly, because the wiring space increases, directly make metal and walk the line on the frame relatively, when this application chose for use yellow light technology, can have certain reduction to the requirement of precision, and then reduce technology cost.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a touch device according to another embodiment of the present disclosure. The first end of the touch lead 20 is electrically connected to the touch electrode located at the landing zone 120 through the conductive connection member 30. One end of the conductive connecting member 30 is connected to the touch lead 20, and the other end is connected to the touch electrode, so that the touch lead 20 and the touch electrode are electrically connected. The Conductive connector 30 may be a Conductive double-sided tape, such as an Anisotropic Conductive Film (ACF). The touch lead 20 is adhered to the touch electrode layer 10 by using a conductive double-sided tape. In this way, the space for adhering the conductive connecting member 30 on the touch electrode layer 10 only needs to be reserved, that is, it is enough to connect the touch lead 20 with the touch electrode in the space, and the space for setting the touch lead 20 is not needed any more, so that the frame area of the touch display panel can be narrowed. In other words, the touch display panel provided by the present application may have a frame width approximately equal to the width of the landing zone. And the width of overlap joint district can be depended on electrically conductive double faced adhesive tape's size, and 0.5 micron can be accomplished to electrically conductive double faced adhesive tape's width, and 0.5 micron just can be accomplished to the overlap joint district of this application so, in order to guarantee good connection effect, can choose for use electrically conductive double faced adhesive tape of 0.5 ~ 10 micron, for example 1 micron, 3 microns, 5 microns etc. is less than the width of current overlap joint district far away. In the current scheme, except that the overlap joint district has the metal to walk the line district in addition for the frame width has 3 ~ 4mm at least, and the micron order can be accomplished to this application, is less than traditional touch panel's frame size far away. For example, the bezel of the touch display panel of the present application may be smaller than 1 mm.

In other embodiments, matching locking structures, such as matching protrusions and grooves, matching snap structures, etc., may be further disposed on the connection region 220 of the touch lead 20 and the landing region 120 of the touch electrode layer 10. The connection between the touch lead 20 and the touch electrode layer 10 is realized by using a locking structure.

The second end of the touch lead 20 is used to connect to a Flexible Printed Circuit (FPC) (not shown), and the FPC is used to connect to a main board of the touch display panel, and can transmit current and signals, thereby having high reliability and excellent flexibility. The touch lead 20 and the FPC may be connected by a conductive adhesive. In this embodiment, the touch lead 20 and the FPC may be externally hung on the touch electrode layer 10, so that the space in the thickness direction of the touch display panel can be reduced, and the purpose of being light and thin is achieved. Similarly, the space in the width direction of the touch display panel can be reduced, and the purpose of narrow frames is achieved. Because the touch lead 20 is flexible and can be bent, when the whole machine is assembled, the touch lead 20 and the FPC are only required to be bent into the shell, the space utilization rate is improved to a greater extent, and meanwhile, the manufacturing cost of the touch display panel is reduced.

Furthermore, the touch lead is designed to be externally hung on the touch electrode layer, so that the preparation process of the touch assembly can be simplified. Under this kind of design, the touch-control lead wire can regard as independent structure module, can independently make the back subsides of accomplishing and adorn on the touch-control electrode layer, can reduce the cost of manufacture.

Based on this, the application provides a touch display panel, and this touch display panel includes display substrate and touch-control subassembly, and the touch-control subassembly sets up on display substrate, and the touch-control lead wire is buckled to the side of being shaded of display substrate.

The display substrate includes an array substrate, which may be a Thin Film Transistor (TFT) substrate, and a light emitting device disposed on the array substrate. The light emitting device may be a Light Emitting Diode (LED), an Organic Light Emitting Diode (OLED), a Micro-LED, or the like. The touch display panel disclosed by the application can be used for various display modes, such as OLED display, quantum dot display, Micro-LED display and the like. The OLED display will be described below as an example, but is not limited to this display mode.

The touch control assembly is arranged on the display substrate. The touch control assembly and the display substrate can be combined in various ways according to the division of the laminated structure. Such as GG structure/GP structure, OGS structure, integrated on-cell structure, integrated in-cell structure, etc.

The GG structure/GP structure type touch display panel is formed by attaching a touch film layer on a glass cover plate/resin cover plate of a display substrate; the OGS structural type touch display panel is characterized in that a touch film layer is attached to a functional film layer such as a polarizer by using optical cement. The integrated on-cell structure is formed by disposing a touch film layer on a light-emitting device layer of a display substrate, such as a thin film encapsulation layer; the integrated in-cell structure is formed by disposing the touch film layer in the light emitting device layer of the display substrate, such as in the thin film encapsulation layer.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a touch display panel according to an embodiment of the present disclosure. In this embodiment, the touch display panel 200 includes a display substrate 50 and a touch device 100. The display substrate 50 includes a TFT array substrate 51, a light emitting device layer 52, and a thin film encapsulation layer 53, and the touch assembly 100 is disposed on the thin film encapsulation layer 53.

The touch film layer can be a film layer only comprising a touch electrode layer, so that the touch film layer can be attached to other structures, and the attaching flatness is improved. At the moment, the touch film layer and the display substrate share the substrate support bearing, so that the total thickness of the touch display panel can be reduced. The touch film layer may also include a transparent substrate and a touch electrode layer to improve the support of the touch film layer.

The touch electrode layer may be a uniaxial touch electrode (e.g., a comb electrode) or a biaxial touch electrode (e.g., two axes are interlaced with each other), and the touch electrode layer may include a single-layer touch electrode, or may include a double-layer or multi-layer touch electrode. The touch electrode layer may be represented by a metal nanowire, a transparent conductive film, or a metal mesh. The metal nanowire may be, for example, a Silver Nanowire (SNW) or a Carbon Nanotube (CNT), and the transparent conductive film may be, for example, Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), or gallium-doped zinc oxide (GZO).

Generally, the touch electrode includes a plurality of first touch electrodes and a plurality of second touch electrodes arranged in an array, the first touch electrodes are arranged along a first direction, the second touch electrodes are arranged along a second direction, and the first touch electrodes are electrically insulated from the second touch electrodes. The first direction may be perpendicular to the second direction, for example, the first touch electrodes may be arranged along a transverse direction, and the second touch electrodes may be arranged along a longitudinal direction, so as to form a touch sensing sensor, so as to respond to the touch signal.

In addition, each first touch electrode and each second touch electrode are respectively electrically connected with a corresponding touch lead. Signals can be input and output to the first touch electrode and the second touch electrode through the touch lead wires. And a plurality of light-transmitting opening patterns are formed on the first touch electrode and the second touch electrode, and each light-transmitting opening pattern is arranged corresponding to each pixel structure in the pixel unit.

The touch assembly can be manufactured and formed first, and then the touch assembly is attached to the display substrate, or the touch assembly is manufactured on a functional film layer of the display substrate.

In one embodiment, the touch film layer includes only the film layer of the touch electrode layer. The formation steps may be, for example but not limited to: providing a bearing substrate, forming a touch electrode layer on the bearing substrate, forming the touch electrode layer by physical vapor deposition, sputtering deposition or photoetching, and removing the bearing substrate to obtain the touch electrode layer. And providing a flexible film layer, forming a metal layer on the flexible film layer, and etching to form a touch lead. And bonding and connecting the flexible film layer with the touch lead with the touch film layer by using the conductive double-sided adhesive tape to form the touch assembly. And then, the touch control assembly is attached to the display substrate by using optical cement, such as being attached to the outer side of the cover plate, the film packaging layer and the functional film layer of the display substrate, such as being attached to a polarizer. In this embodiment, the touch assembly is a thin film layer including only a touch electrode layer, and the thin film layer is flat, so that the flatness of the attachment can be improved. And the touch control display panel and the display substrate share the same substrate, so that the number of the substrates is saved, and the weight and the thickness of the touch control display panel can be reduced.

In one embodiment, the touch film layer may be disposed on a functional film layer of the display substrate. Such as may be provided on a polarizer. The formation steps may be, for example but not limited to: providing a bearing substrate, arranging a polaroid on the bearing substrate, forming a touch electrode layer on the polaroid, forming the touch electrode layer by using a physical vapor deposition, sputtering deposition or photoetching method, and removing the bearing substrate to obtain the polaroid with a touch film layer. And then, adhering a touch lead to the touch film layer to form a polarizer with a touch assembly. The polarizer may be attached to the display substrate using an optical adhesive. By introducing the carrier substrate in the manufacturing process of the touch electrode structure, although the carrier substrate does not form a part of the touch display panel of the final product, the carrier substrate plays a great role in the forming process of the touch electrode structure. The touch electrode structure is formed on the polarizer layer by means of the supporting function of the bearing substrate, and the bearing substrate is removed subsequently, so that the formed touch display panel is lighter and thinner, and the manufacturing cost is lower.

The touch control assembly and the touch control display panel provided by the application can be used for various touch control display devices such as smart phones, tablet computers, televisions, displays, vehicle-mounted display screens and navigators.

The touch display device comprises a control chip and a touch display panel, wherein the touch display panel comprises a touch component, and a touch electrode of the touch component is connected with the control chip through a touch lead wire so as to receive a touch signal. Specifically, the touch lead is connected with the flexible circuit board and then connected with the control chip through the flexible circuit board. In this embodiment, the touch lead and the flexible circuit board may be externally hung on the touch display panel, and when the touch display device is assembled, the touch lead and the flexible circuit board may be bent into the housing. Through the mode, the binding of the touch lead and the flexible circuit board does not occupy too much space, and the purposes of narrow frame, light weight and thinness can be achieved.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims

1. A touch assembly, comprising:

the touch electrode comprises a touch area and a lap joint area;

the touch lead comprises a flexible film and metal wiring arranged on the flexible film, the touch lead is externally hung on the touch electrode, and the first end of the touch lead is electrically connected with the touch electrode in the lap joint area through a conductive connecting piece.

2. The touch assembly of claim 1, wherein the touch lead further comprises:

the protective layer is arranged on one side, far away from the flexible film, of the metal wiring, and the protective layer does not completely cover the metal wiring.

3. Touch control assembly according to claim 1,

the flexible film comprises one or more of a film and a polyethylene terephthalate film.

4. Touch control assembly according to claim 1,

the conductive connecting piece comprises a conductive double-sided adhesive tape.

5. Touch control assembly according to claim 1,

6. Touch control assembly according to claim 1,

the metal wire comprises a metal nanowire;

preferably, the diameter of the metal nanowire is 20-100 nm, and the length of the metal nanowire is 20-100 μm.

7. Touch control assembly according to claim 1,

the thickness of the flexible film is 50-150 mu m;

the width of the metal wire is 5-20 mu m;

the distance between two adjacent metal wires is 5-20 μm.

8. Touch control assembly according to claim 1,

the width of the lap joint area is 0.5-10 mu m.

9. A touch display panel, comprising:

a display substrate and the touch device of any of claims 1-8, the touch device disposed on the display substrate, and the touch lead bent to a backlight side of the display substrate.

10. A preparation method of a touch control assembly is characterized by comprising the following steps:

providing a flexible film, and forming metal wiring on the flexible film to obtain a touch lead;

and electrically connecting the touch lead with a touch electrode positioned in the lap joint area through a conductive connecting piece to obtain a touch assembly.