TWI597648B - Touch panel soft cover layer and manufacturing method thereof - Google Patents

Description

Soft cover layer of touch panel and manufacturing method thereof

The invention relates to a soft cover layer, in particular to a soft cover layer of a touch panel.

Resistive touch panels are common touch panels, accounting for 60% of the global touch panel market, and are the most popular touch panel. Take consumer electronics as an example, such as mobile phones, personal digital assistants (PDAs), electronic dictionaries, self-service ordering systems, inventory management counting machines, checkout machines, credit card signature machines, medical monitoring systems, etc. Control panel. Since the resistive touch panel is pressure-sensitive, it can be operated by hand, pencil, credit card, wooden stick, etc., even if it is worn with gloves, it is quite convenient to use.

The resistive touch panel is mainly composed of a combination of upper and lower sets of indium tin oxide (ITO). When used, the upper and lower electrodes are electrically connected by using pressure, and the position of the contact point is calculated by the controller to detect the change of the panel voltage. The conventional resistive input device can be divided into two types. The first type is an electrode connected to the upper conductive substrate and the electrode connected to the lower conductive substrate is required to be voltage-switched; the second type is an electrode connected to the upper conductive substrate and The electrodes connected to the underlying conductive substrate do not need to be voltage switched.

Please refer to Figure 1 for a schematic diagram of the conventional technology touch panel. First, an indium tin oxide (ITO) conductive layer 12 and a wiring layer 13 are formed on a glass substrate 11, and second, the glass substrate 11 is usually transferred between a processing machine (not shown) by a conveyor.

In this case, if the glass substrate 11 is not smoothly conveyed during the conveyance or the glass substrate 11 is not good, the lamination, the scratch, the crack, and the glass substrate 11 are easily broken. In this way, the yield will not be effectively improved, resulting in the need for more manpower to eliminate problems and maintain the machine.

The disadvantages of transporting conveyors between process machines also include the inability to continuously produce, the main The reason is that the glass substrate 11 is separately processed to each machine for processing, but the general processing machine can only process one glass substrate 11 at a time, and the processing time of each processing machine is also different. Therefore, the glass substrate 11 is often left idle for waiting for the previous substrate processing, so that the touch panel cannot be mass-produced.

In addition, the glass substrate 11 itself cannot be bent, and cannot be applied to a new generation of flexible display devices, such as a smart phone having a display screen around a bezel, a smart watch having a curved display screen, and a roll-out screen. Tablets and personal computers, etc. Mass production of flexible display devices also relies on the support of new technologies. Therefore, how to solve the above problems will be a technical issue that the industry urgently needs to face.

In view of the above disadvantages of the prior art, an object of the present invention is to provide a soft cover layer of a touch panel to solve the problems of laminations, bumps, and cracks that often occur in the process of the touch panel process, and to support a new generation. Flexible display device.

To achieve the above objective, the present invention provides a soft cover layer of a touch panel, comprising: a substrate; an adhesive layer formed on the substrate; a transparent flexible sheet adhered to the substrate via the adhesive layer; a conductive layer formed on the transparent flexible sheet; and a metal circuit layer formed on the transparent conductive layer; wherein the transparent flexible sheet, the transparent conductive layer and the metal wiring layer are rolled to a roller (Roll to Roll) ) formed by the way.

Preferably, a first photoresist pattern layer is formed on the metal circuit layer, and the metal circuit layer and the transparent conductive layer not covered by the first photoresist pattern layer are removed by etching, and the first photoresist pattern layer is removed. And being removed by etching; a second photoresist pattern layer may be formed on the metal circuit layer after etching, and the metal circuit layer not covered by the second photoresist pattern layer is removed by etching, and the second photoresist pattern layer is also removed. Removed by etching.

Preferably, the metal circuit layer can be a continuous circuit layer, a discontinuous circuit layer or a stepped circuit.

Preferably, the substrate can be a glass substrate or a light transmissive flexible substrate.

Preferably, the transparent flexible sheet may be polyethylene terephthalate (PET), polycarbonate (PC), polymethyl. It is made of one of the materials of polymethylmethacrylate (PMMA), Arton transparent resin, Cyclo-olefin polymer (COP), triacetate cellulose (TAC) and Zeonor transparent resin.

Preferably, the transparent conductive layer may be an indium tin oxide (ITO) transparent conductive layer.

Preferably, the metal wiring layer may be made of one of copper, aluminum, silver, gold, and indium tin oxide.

The invention further provides a method for manufacturing a soft cover layer of a touch panel, which solves the problems of laminations, bumps and cracks which often occur in the process of the touch panel process, and can support a new generation of flexible display devices.

To achieve the above objective, a method for fabricating a soft cover layer of a touch panel according to the present invention includes the steps of: forming a transparent conductive layer on a transparent flexible sheet via a roll to roll method and forming a metal wiring layer is formed on the transparent conductive layer; a first photoresist pattern layer is formed on the metal wiring layer; and the metal wiring layer not covered by the first photoresist pattern layer and the transparent conductive layer are removed through etching; Removing the first photoresist pattern layer by etching; forming a second photoresist pattern layer on the metal wiring layer; removing the metal wiring layer not covered by the second photoresist pattern layer by etching; and removing the etching via etching The second photoresist pattern layer.

Preferably, the method further comprises the step of forming an adhesive layer on a substrate.

Preferably, the method further comprises the step of: bonding the transparent flexible sheet to the substrate via the adhesive layer.

The invention replaces the glass substrate of the prior art with a transparent flexible sheet, so that the transparent conductive layer and the metal circuit layer can be bonded to the transparent flexible sheet, and the transparent flexible sheet, the transparent conductive layer and the metal circuit layer are formed by the roller to the roller method. As a result, mass production can be reduced to reduce manufacturing costs. The transparent flexible sheet can be wound into a concentric shape via a roll to a roll, so that it can be continuously produced. And suitably cut to conform to the shape of the substrate, it can be directly bonded to the substrate (glass substrate or flexible substrate). If it is bonded to a flexible substrate, it can be applied to a bendable electronic display device.

11‧‧‧ glass substrate

12‧‧‧Indium tin oxide conductive layer

13‧‧‧Line layer

2‧‧‧Soft overlay of touch panel

21‧‧‧Substrate

22‧‧‧Adhesive layer

23‧‧‧Transparent soft flakes

24‧‧‧Transparent conductive layer

25‧‧‧Metal circuit layer

A~I‧‧‧ steps

1 is a schematic view of a touch panel of the prior art; FIG. 2 is a schematic view of a soft cover layer of the touch panel of the present invention; and FIG. 3 is a transparent flexible sheet, a transparent conductive layer and a metal circuit layer of the present invention from a roller to a roller A schematic diagram of a method for forming a method; and FIG. 4 is a flow chart of a method for fabricating a soft cover layer of the touch panel of the present invention.

The embodiments of the present invention are described by way of specific examples, and those skilled in the art can readily appreciate the other advantages and advantages of the present invention. The invention may be embodied or applied in various other specific embodiments, and various modifications and changes may be made without departing from the spirit and scope of the invention.

It is to be understood that the structure, the proportions, the size and the like of the present invention are intended to be used in conjunction with the disclosure of the specification, and are not intended to limit the scope of the invention. The conditions are not technically meaningful, and any modification of the structure, change of the proportional relationship or adjustment of the size should be disclosed in the present invention without affecting the effects and achievable effects of the present invention. The technical content can be covered.

Please refer to FIG. 2 first, which is an architectural diagram of the present invention. As shown in the figure, the flexible cover layer 2 of the touch panel of the present invention comprises: a substrate 21; an adhesive layer 22 formed on the substrate 21; a transparent flexible sheet 23 adhered to the substrate 21 via the adhesive layer 22; a transparent conductive layer 24 formed on the transparent flexible sheet 23; and a metal wiring layer 25 formed on the transparent conductive layer 24; wherein the transparent flexible sheet 23, the transparent conductive layer 24 and the metal wiring layer 25 are from the drum to the drum ( Roll to Roll) method.

In the embodiment of the present invention, a schematic view of the drum to drum formation is shown in Fig. 3. The drum-to-roller method uses a sheet with flexible properties, typically less than 0.1 cm in thickness, and includes "Unwind", "Process", "Rewind", and "Cut" Cutting) and other process steps. Roller to drum is a high-performance, low-cost continuous production method.

In the embodiment of the present invention, a first photoresist pattern layer (not shown) may be formed on the metal wiring layer 25, and the metal wiring layer 25 and the transparent conductive layer not covered by the first photoresist pattern layer may be formed. 24 is removed by etching, and the first photoresist pattern layer is also removed by etching; a second photoresist pattern layer (not shown) may be formed on the etched metal wiring layer 25, and the metal is not covered by the second photoresist pattern layer. The wiring layer 25 is removed by etching, and the second photoresist pattern layer is also removed by etching.

In an embodiment of the invention, the metal circuit layer 25 can be a continuous circuit layer, a discontinuous circuit layer, or a stepped circuit. Among them, the stepped line can equalize the impedance of the transparent conductive layer 24. Generally, the impedance of the transparent conductive layer 24 increases as the distance increases, and the impedance of the stepped line balances the impedance of the transparent conductive layer 24 by adjusting the distance of each small line to decrease as the distance increases.

Referring to FIG. 2, in the embodiment of the present invention, the substrate 21 can be a glass substrate or a light transmissive flexible substrate. Among them, the light transmissive flexible substrate can be continuously produced by the drum to the drum method, and is a new generation of substrate technology, which has the characteristics of lightness, thinness, impact resistance, non-breaking, convenient carrying, and flexibility.

In the embodiment of the present invention, the transparent flexible sheet 23 may be polyethylene terephthalate (PET), polycarbonate (PC), polymethylmethacrylate (PMMA). It is made of one of Arton transparent resin, Cyclo-olefin polymer (COP), Triacetate Cellulose (TAC) and Zeonor transparent resin.

In an embodiment of the invention, the transparent conductive layer 24 may be an indium tin oxide (ITO) transparent conductive layer. The indium tin oxide transparent conductive layer has characteristics of high conductivity, high visible light penetration, and high infrared light reflection.

In an embodiment of the invention, the metal wiring layer 25 may be made of one of copper, aluminum, silver, gold, and indium tin oxide.

Next, please refer to FIG. 2 and FIG. 4 together. FIG. 4 is a flow chart of the method of the present invention. As shown in the figure, the method for fabricating the soft cover layer 2 of the touch panel provided by the present invention comprises the steps of: forming a transparent conductive layer 24 on a transparent flexible sheet 23 via a roll to roll method, And forming a metal wiring layer 25 on the transparent conductive layer 24 (step A); forming a first photoresist pattern layer (not shown) on the metal wiring layer 25 (step B); removing the first light by etching a metal wiring layer 25 and a transparent conductive layer 24 covered by the pattern layer (step C); removing the first photoresist pattern layer by etching (step D); forming a second photoresist pattern layer on the metal wiring layer 25 (not shown) Show) (step E); removing the layer of the second photoresist pattern without etching The metal wiring layer 25 is covered (step F); and the second photoresist pattern layer is removed via etching (step G).

In this embodiment, the method further includes the step of forming an adhesive layer 22 on a substrate 21 (step H). The adhesive layer 22 can be an Ottical Clear Adhesive (OCA) or an OTPically Clear Resin (OCR).

In this embodiment, the method further includes the step of: the transparent flexible sheet 23 is adhered to the substrate 21 via the adhesive layer 22 (step I). The substrate 21 can be a glass substrate or a light transmissive flexible substrate, wherein the light transmissive flexible substrate can be continuously produced by a roller to a roller method, which is a new generation of substrate technology, which is light and thin on materials. , impact resistance, not easy to break and easy to carry, bendability and other characteristics.

The present invention replaces the glass substrate of the prior art with the transparent flexible sheet 23, so that the transparent conductive layer 24 and the metal wiring layer 25 can be bonded to the transparent flexible sheet 23, and the transparent flexible sheet 23, the transparent conductive layer 24 and the metal wiring layer 25 can be The drum-to-roller method is formed, whereby mass production can be reduced to reduce manufacturing costs. The transparent flexible sheet 23 can be wound into a concentric shape via a roll to a roll, so that it can be continuously produced. And suitably cut to conform to the shape of the substrate, it can be directly bonded onto the substrate 21 (glass substrate or flexible substrate). If it is bonded to a flexible substrate, it can be applied to a bendable electronic display device.

However, the above-described embodiments are merely illustrative of the effects of the present invention, and are not intended to limit the present invention, and those skilled in the art can modify and modify the above embodiments without departing from the spirit and scope of the present invention. . In addition, the number of elements in the above-described embodiments is merely illustrative and is not intended to limit the invention. Therefore, the scope of the invention should be as set forth in the following claims.

2‧‧‧Soft overlay of touch panel

21‧‧‧Substrate

22‧‧‧Adhesive layer

23‧‧‧Transparent soft flakes

24‧‧‧Transparent conductive layer

25‧‧‧Metal circuit layer

Claims (9)

A soft cover layer of a touch panel comprises: a substrate; an adhesive layer formed on the substrate; a transparent flexible sheet adhered to the substrate via the adhesive layer; and a transparent conductive layer formed on the transparent flexible sheet And a metal circuit layer formed on the transparent conductive layer, the metal circuit layer is formed with a first photoresist pattern layer, the metal circuit layer not covered by the first photoresist pattern layer and the transparent conductive layer The first photoresist pattern layer is also removed by etching; the second photoresist pattern layer is formed on the metal circuit layer after etching, and the metal circuit layer is not covered by the second photoresist pattern layer. The second photoresist pattern layer is also removed by etching; wherein the transparent flexible sheet, the transparent conductive layer and the metal wiring layer are formed by a roll to roll method. The soft cover layer of the touch panel of claim 1, wherein the metal circuit layer is a continuous circuit layer, a discontinuous circuit layer or a stepped circuit. The soft cover layer of the touch panel of claim 1, wherein the substrate is a glass substrate or a light transmissive flexible substrate. The soft cover layer of the touch panel of claim 1, wherein the transparent flexible sheet is polyethylene terephthalate (PET), polycarbonate (Polycarbonate, PC). , made of polymethylmethacrylate (PMMA), Arton transparent resin, Cyclo-olefin polymer (COP), triacetate cellulose (TAC) and Zeonor transparent resin. . The soft cover layer of the touch panel of claim 1, wherein the transparent conductive layer is an indium tin oxide (ITO) transparent conductive layer. The soft cover layer of the touch panel of claim 1, wherein the metal circuit layer is made of one of copper, aluminum, silver, gold and indium tin oxide. A method for fabricating a soft cover layer of a touch panel, comprising the steps of: forming a transparent conductive layer on a transparent flexible sheet via a roll to roll method, and forming a metal circuit layer on the transparent conductive layer Forming a first photoresist pattern layer on the metal wiring layer; removing the metal wiring layer not covered by the first photoresist pattern layer and the transparent conductive layer via etching; removing the first photoresist pattern via etching Forming a second photoresist pattern layer on the metal wiring layer; removing the metal wiring layer not covered by the second photoresist pattern layer by etching; and removing the second photoresist pattern layer by etching. The method for fabricating the soft cover layer of the touch panel of claim 7, further comprising the step of: forming an adhesive layer on a substrate. The method for fabricating a soft cover layer of a touch panel according to claim 8, further comprising the step of: bonding the transparent flexible sheet to the substrate via the adhesive layer.