CN108920028B

CN108920028B - Touch module

Info

Publication number: CN108920028B
Application number: CN201810643178.6A
Authority: CN
Inventors: 杨岳峰; 黄彦衡; 陈柏林; 金鸿杰; 曾哲纬; 刘菊香
Original assignee: Interface Optoelectronics Shenzhen Co Ltd; Interface Technology Chengdu Co Ltd; General Interface Solution Ltd
Current assignee: Interface Optoelectronics Shenzhen Co Ltd; Interface Technology Chengdu Co Ltd; General Interface Solution Ltd
Priority date: 2018-06-21
Filing date: 2018-06-21
Publication date: 2021-06-11
Anticipated expiration: 2038-06-21
Also published as: TW202001523A; TWI661347B; CN108920028A

Abstract

The invention provides a touch module for preventing a touch sensing film from generating cracks, which comprises the touch sensing film, a scratch-resistant hardened layer, a flexible circuit board and a bearing body. The scratch-resistant hardened layer is connected with the touch sensing film through an optical adhesive layer and has a first thickness. The flexible circuit board is electrically connected with the touch sensing film through an anisotropic conductive film. The carrier is disposed on the other surface of the flexible circuit board, and the anisotropic conductive film, the flexible circuit board and the carrier have a second thickness. Wherein the difference between the first thickness and the second thickness is less than 20 μm.

Description

Touch module

Technical Field

The present invention relates to the field of touch devices, and more particularly, to a touch module for preventing a touch sensing film from cracking.

Background

Touch screens have been widely used in various aspects of daily life as a simple and convenient way of human-computer interaction. According to the touch sensing principle, touch screens are mainly classified into resistive, capacitive, surface infrared touch screens and the like. The capacitive touch screen has the advantages of simple structure, high light transmittance, friction resistance, environmental humidity and temperature change resistance, long service life, capability of realizing multi-point touch and the like, and thus the capacitive touch screen becomes the mainstream of the touch screen market.

With the continuous development of science and technology, the thickness of the capacitive touch screen is required to be thinner and thinner to meet the requirements of lightness and thinness of mobile terminals and the like. Therefore, a capacitive touch screen starts to adopt a thin film capacitive touch screen having a panel glass and a thin film touch sensor attached to the panel glass. In the process of manufacturing the thin film capacitive touch screen, the metal mesh sensing film can be attached to other elements through the optical adhesive to be subjected to punch forming (punch forming), however, in the process of punch forming, due to the fact that the thickness of each element is different, a break exists, and cracks (craks) are easily generated on the touch sensing line to cause defects, as shown in an arrow of fig. 1, and therefore, there is still room for improvement.

Disclosure of Invention

The main objective of the present invention is to provide a touch module capable of preventing the touch sensing film from cracking, so that the touch sensing circuit will not break when the touch sensing film is attached. In order to achieve the above object, the present invention provides a touch module for preventing a touch sensing film from cracking, comprising: a touch-control response membrane, a scratch-resistant hardened layer, a flexible circuit board and a supporting body. The touch sensing film has a first surface and a second surface. The scratch-resistant hardened layer is connected with the first surface through an optical adhesive layer, and the scratch-resistant hardened layer and the optical adhesive layer have a first thickness. One surface of the flexible circuit board is provided with a welding pad area, the welding pad area is electrically connected with the first surface through an anisotropic conductive film, and a gap is reserved between the scratch-resistant hardened layer and the flexible circuit board. The carrier is arranged on the other surface of the flexible circuit board and corresponds to the welding pad area, and the anisotropic conductive film, the flexible circuit board and the carrier have a second thickness. Wherein the difference between the first thickness and the second thickness is less than 20 μm.

In an embodiment of the invention, the touch sensing film is a metal mesh sensing film.

In an embodiment of the present invention, the carrier is made of a heat-resistant material, and the heat resistance is higher than 150 ℃.

In one embodiment of the present invention, the light transmittance of the carrier is greater than 50 percent.

In an embodiment of the invention, a contact range of the carrier and the flexible circuit board has a first width, a contact range of the anisotropic conductive film and the flexible circuit board has a second width, and a length of the first width is greater than a length of the second width.

In an embodiment of the present invention, the material of the carrier includes polyimide.

In one embodiment of the present invention, the gap is not greater than 0.7 mm.

In an embodiment of the invention, the second surface has a second optical adhesive layer thereon for adhering the touch sensing film to a display, wherein the display is a liquid crystal display module.

Drawings

Fig. 1 is a schematic view of a touch sensing line crack.

FIG. 2 is a schematic structural diagram of a touch module according to an embodiment of the invention.

FIG. 3 is a schematic structural diagram of a touch module according to another embodiment of the invention.

Reference numerals:

touch control induction film 1 film 11

Drive electrode 12 sense electrode 13

First surface 14 and second surface 15

Scratch-resistant hardened layer 2 flexible circuit board 3

Surfaces

31,33 pad areas 32

Carrier 4 optical cement layer 5

Anisotropic conductive film 6 second optical adhesive layer 7

Roller 8 first thickness W1

Second thickness W2 first width L1

Second width L2 third width L3

Fourth width L4 gap D

Detailed Description

To achieve the above objects and advantages, the technical means and structure adopted by the present invention are described in detail with reference to the following drawings for fully understanding the features and functions of an embodiment of the present invention, but it should be noted that the contents do not limit the present invention.

Fig. 2 is a schematic structural diagram of a touch module according to an embodiment of the invention. The invention provides a touch module for preventing a touch sensing film from generating cracks, which comprises: a touch sensing film 1, a scratch-resistant hardened layer 2, a flexible circuit board 3 and a carrier 4.

The touch sensing film 1 has a first surface 14 and a second surface 15, and the touch sensing film 1 may be a metal mesh sensing film including a film 11, a driving electrode (Tx)12 and a sensing electrode (Rx) 13.

The scratch-resistant hardened layer 2 may be a resin material (PET) subjected to a surface hardening treatment, for example, a Silicon-based (Silicon-based) layer is coated on the surface of the resin material. The scratch-and-cure-preventing layer 2 is connected to the first surface 14 through an optical adhesive layer 5. in an embodiment of the present invention, the scratch-and-cure-preventing layer 2 is connected to the first surface 14 through a stamping method. Wherein, the scratch-resistant layer 2 and the optical adhesive layer 5 have a first thickness W1.

One surface 31 of the flexible circuit board 3 has a bonding pad area (bonding pad)32, and the bonding pad area 32 is electrically connected to the first surface 14 through an Anisotropic Conductive Film (ACF) 6 for transmitting the touch signal of the touch sensing Film 1. The anisotropic conductive film 6 is synthesized from resin and conductive particles and used for connecting two different substrates and electronic circuits, and the anisotropic conductive film 6 has the advantages of wire thinning, simple process, and good moisture resistance, adhesion, conductivity and insulation. The scratch-resistant hardened layer 2 is separated from the flexible circuit board 3 by a gap D, and the gap D is a fitting tolerance and is not more than 0.7 mm.

The carrier 4 is disposed on the other surface 33 of the flexible circuit board 3 and is disposed only in the area of the pad area 32. The carrier 4 is made of a transparent material or a semi-transparent material, and is made of a heat-resistant material, which may include polyimide, and the heat-resistant material has a temperature of more than 150 ℃ in response to the fog (fpc on glass) process, and the light transmittance of the carrier 4 is more than 50% so as to monitor the alignment of the bonding pad (pad) process and the cracking of the conductive particles. The anisotropic conductive film 6, the flexible circuit board 3 and the carrier 4 have a second thickness W2, and the difference between the first thickness W1 and the second thickness W2 is less than 20 μm.

In an embodiment of the invention, a contact range between the carrier 4 and the flexible circuit board 3 has a first width L1, a contact range between the anisotropic conductive film 6 and the flexible circuit board 3 has a second width L2, and a length of the first width is greater than a length of the second width, so that stability of the touch module during stamping (punch) can be improved.

In an embodiment of the present invention, the second surface 15 further has a second optical adhesive layer 7, and the second optical adhesive layer 7 can be coated on the second surface 15 through a roller 8, so as to adhere the touch sensing film 1 to a display (not shown), which can be a liquid crystal display module or a backlight module.

Please refer to fig. 3, which is a schematic structural diagram of a touch module according to another embodiment of the invention. In another embodiment of the present invention, the carrier 4 is also disposed on the other surface 33 of the flexible circuit board 3 and extends along the edge of the flexible circuit board 3 toward the scratch-resistant hardened layer 2. The contact range between the carrier 4 and the flexible circuit board 3 has a third width L3, the contact range between the anisotropic conductive film 6 and the flexible circuit board 3 has a fourth width L4, and the length of the third width L3 is greater than the length of the fourth width L4. Through the structure, the touch module can be more stable when being subjected to punch forming (punch).

Therefore, referring to all the drawings, compared with the prior art, the touch module for preventing the touch sensing film from cracking provided by the invention has the advantages that the semitransparent material is arranged below the welding pad area of the flexible circuit board, so that the fault between the flexible circuit board and the scratch-resistant hardened layer is made up, and the defect of touch sensing circuit cracking caused by thickness fault in the subsequent attaching process of the touch module is overcome.

Through the above detailed description, it is fully evident that the objects and effects of the present invention are advanced by practice, and have industrial applicability, and are fully in line with the patent requirements of the invention and the appended claims. While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims

1. A touch module, comprising:

a touch sensing film having a first surface and a second surface;

the scratch-resistant hardened layer is connected with the first surface through an optical adhesive layer, and the scratch-resistant hardened layer and the optical adhesive layer have a first thickness;

a flexible circuit board, wherein a surface of the flexible circuit board is provided with a welding pad area which is electrically connected with the first surface through an anisotropic conductive film, and a gap is reserved between the scratch-resistant hardened layer and the flexible circuit board; and

a carrier, which is arranged on the other surface of the flexible circuit board and made of heat-resistant material, and the transmittance of the carrier is more than 50 percent in response to the FOG process, so as to monitor the alignment of the bonding pad process and the cracking condition of the conductive particles, and the anisotropic conductive film, the flexible circuit board and the carrier have a second thickness corresponding to the bonding pad area;

wherein a difference between the first thickness and the second thickness is less than 20 microns.

2. The touch module of claim 1, wherein the touch sensing film is a metal mesh sensing film.

3. The touch module as recited in claim 1, wherein the heat-resistant material is polyimide and has a heat resistance higher than 150 ℃.

4. The touch module of claim 1, wherein the contact area between the carrier and the flexible circuit board has a first width, the contact area between the anisotropic conductive film and the flexible circuit board has a second width, and the length of the first width is greater than the length of the second width.

5. The touch module of claim 1, wherein the flexible printed circuit board has a pad area on one surface thereof, the pad area is electrically connected to the first surface through the anisotropic conductive film for transmitting the touch signal of the touch sensing film, and the anisotropic conductive film is formed by combining resin and conductive particles for connecting two different substrates and electronic circuits.

6. The touch module of claim 1, wherein the gap is no greater than 0.7 mm.

7. The touch module of claim 1, wherein the second surface has a second optical adhesive layer thereon for adhering the touch sensing film to a display.

8. The touch module of claim 7, wherein the display is a liquid crystal display module.

9. The touch module of any of claims 1-8, wherein the carrier is disposed on another surface of the flexible circuit board and extends along an edge of the flexible circuit board toward the anti-scratch-cure layer; the contact range of the carrier and the flexible circuit board has a third width, the contact range of the anisotropic conductive film and the flexible circuit board has a fourth width, and the length of the third width is greater than that of the fourth width; should prevent scraping sclerosis layer and this supporting body and be less than this and prevent scraping sclerosis layer and this flexible circuit board apart from the clearance, see through above-mentioned structure, can make the touch module more stable when carrying out stamping forming.