TWI408576B - Insulating layer of low capacitive property and touch sensor having the same - Google Patents

Abstract

The present invention presents a touch sensor structure having an insulating layer with a low capacitive property. The material composition of the insulating layer in the touch sensor structure provided in this invention has a dielectric constant less than 5. Because of this invention, electric charge accumulated on the insulating layer during the manufacturing process of the sensor structure that affects its charge speed may be avoided, and the power consumption of the touch panel can be reduced, thereby promoting transparency and sensitivity of the touch panel.

Description

Low-capacitance insulating layer and touch sensing structure having the same

The present invention relates to an insulating layer design and a touch sensing structure having the same, particularly relates to an insulating layer design of a touch panel and a corresponding sensing structure thereof.

At present, various types of electronic devices have widely used touch technology as an input method thereof, thereby being able to read information or transmit information by simply pressing a display panel with a finger or a stylus, thereby eliminating the need for conventional electronic devices. A button, keyboard, or slider that must be configured.

Touch panels are mainly classified into resistive, capacitive, infrared, and ultrasonic based on their sensing principles. Infrared and ultrasonic touch panels are placed on one side of the X-axis and Y-axis of the screen. Infrared or ultrasonic source, and the receiving source is installed on the other side. When the user touches the screen, the movement of the infrared or ultrasonic wave is disturbed, and the touch input is completed by measuring and confirming the disturbed position coordinates. The resistive touch panel is formed by laminating two sets of upper and lower ITO (indium tin oxide) conductive films. After the upper and lower electrodes are turned on by pressure, the position of the contact point is calculated by the controller to detect the voltage change of the panel for input. The capacitive touch panel is made up of transparent glass coated with oxidized metal on the surface, which is supplied with voltage from four corners and forms a uniform electric field on the surface of the glass, which is generated by the electrostatic reaction between the user's finger and the electric field. Capacitance changes to detect input coordinates.

In the capacitive touch panel, the upper and lower electrode plates are provided with an insulating layer or a spacer Dots design, thereby forming a capacitive touch sensing structure; however, in the manufacturing process, the upper and lower electrode layers are coupled. Partial meeting The phenomenon of charge accumulation in the insulating layer due to the effect of the parasitic capacitance of the insulating layer, thereby forming a pressure loss, leads to an increase in the power consumption when the touch panel is used, and also increases the time required for charging the touch sensing structure. In addition, in the conventional process, the germanium dioxide insulating layer between the upper and lower electrode plates is formed by an expensive thin film process (for example, by sputtering deposition), and the process thereof is complicated, and the manufacturing cost is also very high. .

For the sake of his post, the applicant has carefully tested and researched it and proposed a "low-capacitance insulating layer and a touch-sensing structure with this insulating layer" in the spirit of perseverance. According to the present invention, a touch sensing structure having a low-capacitance insulating layer can be obtained, the power consumption of the touch panel can be reduced, and the transmittance and sensitivity of the touch panel can be improved. Moreover, the present invention has a lower manufacturing cost. Advantage.

The first concept of the present invention is to provide a capacitive touch panel sensing structure having an insulating layer with low capacitance characteristics, thereby improving the charge accumulation and reducing the power consumption of the panel.

A second aspect of the present invention provides a capacitive touch panel sensing structure having an insulating layer with low capacitance characteristics, thereby reducing the time required for charging the touch sensing structure and increasing the recovery speed thereof.

The above concept can be realized by the sensing structure of the touch panel and the touch panel provided by the present invention.

The present invention provides a sensing structure for a touch panel, comprising: a substrate having a first surface; a first electrode layer patterned to be spaced apart from the first portion of the first surface a plurality of island structures; an insulating layer covering each of the island structures to expose a second portion of the first surface; and a second electrode layer covering the The edge layer and the second portion of the first surface, wherein the insulating layer is made of a material having a dielectric constant lower than 5.

The present invention also provides a sensing structure of a touch panel, comprising: a substrate having a first surface; a first electrode layer including a first portion and a second portion, wherein the a first portion is disposed on the first surface; an insulating layer is disposed on the first portion of the first electrode layer; a plurality of filling holes are located in the insulating layer and penetrate therethrough, the first electrode layer The second portion is disposed on the insulating layer and connected to the second portion via the filling holes; and a second electrode layer is patterned to be partially disposed on the insulating layer and The second portion of an electrode layer is isolated, wherein the insulating layer is made of a material having a dielectric constant of less than 5.

The present invention also provides a two-dimensional sensing structure of a capacitive touch panel, comprising: a substrate having a plurality of conductive units on a first surface thereof; an insulating layer on the substrate and patterned A plurality of insulators, wherein each of the insulating systems corresponds to each of the conductive units; and an electrode layer on the insulating layer, wherein the insulating layer is made of a material having a dielectric constant lower than 5.

The present invention further provides a capacitive touch panel, comprising: a substrate having a first surface; a sensing unit disposed on the first surface, the sensing unit including a first electrode, a first a second electrode and an organic insulating layer between the first electrode and the second electrode, wherein the organic insulating layer is composed of a dielectric constant lower than 5; and a protective layer is disposed on the sensing unit .

According to the above concept, the thickness of the insulating layer is between 0.05 μm and 2 μm.

According to the above concept, the insulating layer is formed of an organic material, a photosensitive initiator and a coupling agent.

According to the above concept, the photosensitive initiator is contained in an amount of between 1% and 10%.

According to the above concept, the content of the coupling agent is between 0.1% and 3%.

According to the above concept, the organic material includes an acrylic resin, an acrylic monomer, and an ether.

According to the above concept, wherein the ether is selected from the group consisting of diethylene glycol dimethyl ether or diethylene glycol methyl ethyl ether.

According to the above concept, wherein the ether is diethylene glycol dimethyl ether, and the organic material further comprises propylene glycol monomethyl ether acetate.

According to the above concept, the content of the diethylene glycol dimethyl ether is between 20% and 50%.

According to the above concept, wherein the ether is diethylene glycol methyl ethyl ether, and the content thereof is between 70% and 85%.

According to the above concept, the organic material further includes one of an epoxy resin, a methacrylate copolymer, and a combination thereof.

According to the above concept, the content of the acrylic resin is between 5% and 30%.

According to the above concept, the content of the acrylic monomer is between 5% and 30%.

According to the above concept, the transmittance of the insulating layer is greater than 90%.

The case can be further deepened by the following diagrams and detailed explanations. Learn to:

Please refer to the first figure, which is a partial cross-sectional view for explaining the basic structure of the capacitive touch panel sensing structure of the present invention. The capacitive touch panel sensing structure 1 of the present invention includes a substrate 10, a sensing unit 12 on the surface of the substrate 10, and a sensing unit 12 for protecting the structure of the sensing unit 12. A protective layer 14 includes a first electrode 121, a second electrode 122, and an organic insulating layer 123 between the first electrode 121 and the second electrode 122. An advantage of the present invention is that the organic insulating layer 123 is composed of a dielectric layer 123 having a dielectric constant of less than 5 and a transmittance of greater than 90%.

In the present invention, in order to reduce the capacitance characteristics of the insulating layer to improve the parasitic capacitance effect of the insulating layer, the material composition of the insulating layer is continuously adjusted and tried to meet the cost-effective process conditions and requirements to produce a dielectric constant lower than 5 insulation layer design. In a preferred embodiment of the present invention, the insulating layer is formed of an organic material, and contains a photoinitiator (Photo Initiator) in an amount of 1% to 10% and a coupling agent (Coupling) in an amount of 0.1% to 3%. Agent). In the present invention, the organic material of the insulating layer comprises an acrylic resin (Acrylic Resin) in an amount of 5% to 30%, an acrylic monomer (Acrylic Monomer) in an amount of 5% to 30%, and an ether (Ether) in which an ether is used. It is Diethylene Glycol Dimethyl Ether or Diethylene Glycol Methylethyl Ether. In addition, the organic material of the insulating layer may further include an epoxy resin (Epoxy), a Methacrylate Copolymer, a Propylene Glycol Monomethyl Ether Acetate (PGMEA), or a combination thereof. Things and so on. The following table (1) The composition and content of the four insulating layer materials of the present invention are listed.

According to the present invention, the thickness of the insulating layer is between 0.05 μm and 2 μm, depending on the film formation process selected, and the cost-effective spin coating method and slit coating method (Slit) Coating) and alignment coating (PI Coating) are all feasible processes.

The insulating layer having the above composition can also be applied to other forms of touch panel sensing structures; an example will be described below.

Please refer to FIG. 2A to FIG. 2D for illustrating a manufacturing process of the touch panel sensing structure and a schematic cross-sectional view of the formed sensing structure according to a preferred embodiment of the present invention. As shown in FIG. 2A, the touch panel sensing structure of the present invention is mainly constructed on one surface of the substrate 20; the first electrode layer 21 is formed on the substrate 20, and the first electrode layer 21 is patterned into a plurality of islands disposed on a portion of the surface 20a of the substrate 20 Structures 21a, 21b, and 21c; then, a low-capacitance insulating layer 23 is formed by spin coating, slit coating, or alignment film coating, which covers the island structures 21a, 21b, and 21c, respectively. And exposing another portion of the surface 20b of the substrate 20 as shown in FIG. Forming a second electrode layer 22 on the low-capacitance insulating layer 23, covering the insulating layer and the substrate surface 20b, thereby forming a sensing array having an island-shaped insulator (as shown in FIG. 2C); In the present invention, the material composition of the low-capacitance insulating layer 23 is adjusted to have a dielectric constant of less than 5 in accordance with Table (1).

In this embodiment, the other surface of the substrate 20 of the sensing structure is directly formed with the color filter layer 25, and the positions of the island structures 21a, 21b and 21c of the first electrode layer 21 correspond to the black frame layer 24. Each of the upper BM regions forms a module of the capacitive touch panel sensing structure 2 having a low capacitance insulating layer, as shown in the second D.

Please refer to the third drawing, which illustrates a schematic cross-sectional view of a touch panel sensing structure according to another preferred embodiment of the present invention. As shown in the third figure, the touch panel sensing structure 3 of the present invention is also formed on the substrate 30 on which the black frame layer 34 and the color filter layer 35 are formed, and includes a first electrode layer 31 and a second electrode layer. 32 and a low-capacitance insulating layer 33, wherein the first electrode layer 31 is composed of a first portion 311 on the surface of the substrate 30 and a second portion 312 on the low-capacitance insulating layer 33, the first electrode layer The first portion 311 and the second portion 312 of the 31 are connected by a plurality of filling holes 315 penetrating the low capacitance insulating layer 33, and the second electrode layer is patterned to be disposed in a portion of the low capacitance insulating layer 33. Is isolated from the second portion 312 of the first electrode layer 31, thereby forming a touch panel sense of a through-hole type having a low capacitance characteristic Test module.

The two-dimensional sensing structure can be constructed by the upper and lower electrode layers. According to the present invention, the low-capacitance insulating layer can also be patterned to be further applied to patterned indium tin oxide having a plurality of conductive elements ( In the touch sensing structure constructed by the ITO film, a capacitive touch panel sensing structure having a low capacitance insulating layer of the present invention is formed.

The present invention provides an insulating layer having low capacitance characteristics by adjusting the material composition of the insulating layer, which is compatible with existing cost-effective film forming processes (for example, spin coating, slit coating, and alignment film coating procedures). The conditions of the process are compatible with the yellow light process; the present invention has industrial promotion potential compared to the conventional thin film process which is expensive and complicated by sputtering. Since the low-capacitive insulating layer of the present invention has a low dielectric constant, the portion where the upper and lower electrode layers are coupled does not cause charge accumulation in the insulating layer due to the effect of the parasitic capacitance of the insulating layer during the manufacturing process. This can reduce the power consumption of the panel when used, and can reduce the time required for the touch sensing structure to be charged and improve the recovery speed.

Therefore, this case is a novel, progressive and industrially practical and competitive invention, which has profound development value.

The present invention has been modified by those skilled in the art, and is not intended to be limited by the scope of the application.

1, 2, 3‧‧‧ touch panel sensing structure

10, 20, 20a, 20b, 30‧‧‧ substrates

12‧‧‧Sensor unit

121‧‧‧First electrode

122‧‧‧second electrode

123‧‧‧Low capacitance characteristic insulation layer

14‧‧‧Protective layer

21, 31‧‧‧ first electrode layer

21a, 21b, 21c‧‧‧ island structure

311‧‧‧The first part of the first electrode layer

312‧‧‧The second part of the first electrode layer

315‧‧‧Drilling

22, 32‧‧‧ second electrode layer

23, 33‧‧‧ Low capacitance characteristic insulation layer

24, 34‧‧‧ black frame

25, 35‧‧‧ color filter layer

The first figure is a partial cross-sectional view for explaining the basic structure of the capacitive touch panel sensing structure of the present invention; the second to second D drawings are touch type according to a preferred embodiment of the present invention. a manufacturing process of the panel sensing structure and a schematic cross-sectional view of the sensing structure formed thereof; The third figure is a schematic cross-sectional view of a touch panel sensing structure in accordance with another preferred embodiment of the present invention.

1‧‧‧Touch panel sensing structure

10‧‧‧Substrate

12‧‧‧Sensor unit

121‧‧‧First electrode

122‧‧‧second electrode

123‧‧‧Low capacitance characteristic insulation layer

14‧‧‧Protective layer

Claims (17)

A sensing structure of a touch panel includes: a substrate having a first surface; a first electrode layer patterned to be spaced apart from a plurality of islands disposed on a first portion of the first surface a structure, an insulating layer covering each of the island structures to expose a second portion of the first surface; and a second electrode layer covering the insulating layer and the first surface In the two parts, the material composition of the insulating layer is such that it has a dielectric constant lower than 5. The sensing structure of claim 1, wherein the insulating layer has a thickness of between 0.05 μm and 2 μm. The sensing structure of claim 1, wherein the insulating layer is formed of an organic material, a photosensitive initiator and a coupling agent. The sensing structure of claim 3, wherein the photosensitive initiator is present in an amount between 1% and 10%. The sensing structure of claim 3, wherein the amount of the coupling agent is between 0.1% and 3%. The sensing structure of claim 3, wherein the organic material comprises an acrylic resin, an acrylic monomer, and an ether. The sensing structure of claim 6, wherein the ether is selected from the group consisting of diethylene glycol dimethyl ether and diethylene glycol methyl ethyl ether. One of them. The sensing structure according to claim 7, wherein the ether is diethylene glycol dimethyl ether, and the organic material further comprises propylene glycol monomethyl ether acetate. The sensing structure of claim 8, wherein the diethylene glycol dimethyl ether is present in an amount between 20% and 50%. The sensing structure of claim 7, wherein the ether is diethylene glycol methyl ethyl ether and the content is between 70% and 85%. The sensing structure of claim 6, wherein the organic material further comprises one of an epoxy resin, a methacrylate copolymer, and a combination thereof. The sensing structure of claim 6, wherein the acrylic resin is present in an amount of between 5% and 30%. The sensing structure of claim 6, wherein the content of the acrylic monomer is between 5% and 30%. The sensing structure of claim 1, wherein the insulating layer has a transmittance greater than 90%. A sensing structure of a touch panel includes: a substrate having a first surface; a first electrode layer including a first portion and a second portion, wherein the first portion is Located on the first surface; an insulating layer on the first portion of the first electrode layer; a plurality of filling holes, located in the insulating layer and penetrating therebetween, the second portion of the first electrode layer being located on the insulating layer and connected to the first portion via the filling holes; and a second electrode a layer patterned to be partially disposed on the insulating layer and isolated from the second portion of the first electrode layer, wherein the insulating layer is made of a material having a dielectric constant lower than 5. A two-dimensional sensing structure of a capacitive touch panel, comprising: a substrate having a plurality of conductive units on a first surface thereof; an insulating layer on the substrate and patterned to have a plurality of insulators Each of the insulating systems corresponds to each of the conductive units; and an electrode layer is disposed on the insulating layer, wherein the insulating layer is formed of an organic material and has a dielectric constant of less than 5. A capacitive touch panel includes: a substrate having a first surface; a sensing unit disposed on the first surface, the sensing unit including a first electrode, a second electrode, and the An organic insulating layer between the first electrode and the second electrode, wherein the organic insulating layer is composed of a dielectric constant lower than 5; and a protective layer is disposed on the sensing unit.