TWI703479B - Touch module device and manufacturing method thereof - Google Patents

Abstract

A touch module includes a touch sensor layer, protective material, a transparent adhesive region, a flexible printed circuit and a screen-printed insulation paste layer. The perspective material is on the touch sensor layer. The transparent adhesive region is positioned between the touch sensor layer and the perspective material. The flexible printed circuit is electrically attached to the touch sensor layer using a conductive adhesive. The screen-printed insulation paste layer is positioned over the flexible printed circuit and adjacent the transparent adhesive region. Covering over the flexible printed circuit and filling in the empty space between the transparent adhesive region and the flexible printed circuit, the screen-printed insulation paste layer is formed using a screen-printing process.

Description

Touch control module and manufacturing method thereof

The disclosure relates to a touch module and its manufacturing method.

Touch modules, such as capacitive touch screens, are implemented through a transparent touch sensing layer. When the user’s fingertips touch the touch screen, the transparent touch sensing layer of the touch screen will feel the finger The local capacitance change brought about by the corresponding signal can be transmitted to the corresponding driving element through the flexible printed circuit electrically connecting the transparent touch sensing layer and the touch screen, thereby driving the display to achieve the touch function.

In the prior art, after the electrical connection between the flexible printed circuit and the transparent touch sensing layer is completed, the exposed flexible printed circuit is coated with silicone for protection. Silicone usually uses glue to cover the flexible printed circuit. However, for Silicone that uses a dispensing method to cover the flexible printed circuit, the cover glass used to protect the transparent touch sensor layer will have the undesirable phenomenon of dents and bubble-like appearance. Moreover, some touch modules will not have enough space for glue dispensing and will not be able to use Silicone protection circuits.

One technical aspect of this disclosure is a touch module.

According to an embodiment of the present disclosure, a touch module includes a touch sensing layer, a protective plate, a transparent adhesive area, a flexible printed circuit, and a screen-printed insulating adhesive layer. Touch sensing layer electrode area. The protective plate is located above the touch sensing layer. The transparent adhesive area is located between the touch sensing layer and the protection board. The flexible printed circuit is located on the touch sensing layer, and the electrical connection area of the flexible printed circuit is electrically attached to the electrode area of the touch sensing layer with conductive glue. The screen-printed insulating glue layer is located on the flexible printed circuit and is adjacent to the transparent glue area, and is filled between the transparent glue area and the flexible printed circuit.

In an embodiment of the present disclosure, the touch sensing layer of the above-mentioned touch module is an insulating layer with an indium tin oxide film pattern or a metal mesh pattern.

In an embodiment of the present disclosure, the conductive adhesive of the flexible printed circuit of the touch module is anisotropic conductive adhesive.

In an embodiment of the present disclosure, the screen-printed insulating layer of the above-mentioned touch module is a cold ultraviolet curable insulating glue. The thickness of the screen-printed insulating glue layer is between 6 μm and 75 μm, and the thickness of the screen-printed insulating glue layer is smaller than the thickness of the transparent glue layer. In addition, the surface impedance of the screen-printed insulating adhesive layer is between 1x10 ¹⁰ Ω/□ to 1x10 ¹³ Ω/□.

In an embodiment of the present disclosure, the protective plate of the touch module is a cover glass.

In one embodiment of the present disclosure, the light-transmitting glue area of the touch module is optically transparent glue.

Another technical aspect of the present disclosure is a method of manufacturing a touch module.

According to one embodiment of the present disclosure, a method of manufacturing a touch module includes providing a touch sensing layer, forming an optically transparent glue area on the touch sensing layer, attaching a flexible printed circuit to the touch sensing layer, and then screen printing insulating glue The layer covers the electrical connection area between the flexible printed circuit and the touch sensing layer, and uses cold ultraviolet light to cure the insulating glue layer so that the thickness of the insulating glue layer is smaller than the thickness of the optically transparent glue area.

In one embodiment of the present disclosure, the method for producing the module's touch on the use of UV curable insulating adhesive layer cooling step, the temperature of this step is within a range from 25 ^o C to 50 ^o C to.

In the above-mentioned embodiments of the present disclosure, a screen-printed insulating adhesive layer is used to protect the circuit, and has the functions of insulation and waterproofing. Compared with the dispensing method, the thickness of the screen-printed insulating adhesive layer is more consistent and uniform, which improves the use of the touch structure in the space of the protection circuit, and therefore reduces the exposure of some types of touch structures due to insufficient space. The problem that metal lines cannot be protected. In addition, since the uniform thickness of the screen-printed insulating adhesive layer is less than the thickness of the adhesive area, the original uneven thickness of the glue layer exceeds the thickness of the adhesive layer of the touch module, resulting in poor appearance of dents and foamy appearance Bad problems can also be improved.

The present invention is described with reference to the accompanying drawings, in which similar reference numerals are used for similar or equivalent components. The drawings are not drawn according to actual size, but are merely provided to illustrate the present invention.

FIG. 1 is a schematic top view of the touch module 100 according to an embodiment of the disclosure. Figure 2 shows a cross-sectional view of Figure 1 along line 2-2. Referring to FIG. 1 and FIG. 2 at the same time, in this embodiment, the touch module 100 includes a touch sensing layer 110, a protective plate 120, a transparent adhesive area 130, a flexible printed circuit 142 and a screen-printed insulating adhesive layer 146. As shown in FIG. 1, the touch sensing layer 110 has an electrode area 110 a, and the flexible printed circuit 142 is electrically connected to the electrode area 110 a of the touch sensing layer 110.

As shown in FIG. 2, the protection plate 120 is located above the touch sensing layer 110. In this embodiment, the protective plate 120 used in the touch module 100 is a cover lens.

As shown in FIG. 2, the light-transmitting adhesive area 130 is located between the touch sensing layer 110 and the protection plate 120, and is used for attaching the protection plate 120 to the touch sensing layer 110 to protect the touch sensing layer 110. In this embodiment, the transparent adhesive area 130 is an optical clear adhesive (Optical clear adhesive 1, OCA1). When the touch module 100 is applied to a display module, the transparent optical clear adhesive will not affect the display module too. Many functions.

In FIG. 2, the flexible printed circuit 142 is located on the touch sensing layer 110, and the electrical connection area 142 a of the flexible printed circuit 142 is electrically attached to the electrode area 110 a of the touch sensing layer 110 using a conductive adhesive 144. As shown in FIGS. 1 and 2, in this embodiment, only the electrical connection area 142a of the flexible printed circuit 142 is connected to the touch sensitive layer 110, and the touch sensitive layer 110 is connected through the flexible printed circuit 142 To external control components and/or drive components to transmit electronic signals.

In this embodiment, the conductive adhesive 144 used in the flexible printed circuit 142 is anisotropic conductive film (ACF). This anisotropic conductive film is an adhesive that conducts electricity in the vertical direction. The circuit 142 can be electrically connected with the touch sensing layer 110 to realize the touch function.

The screen-printed insulating glue layer 146 is located on the flexible printed circuit 142 and is adjacent to the light-transmitting glue area 130, and the screen-printed insulating glue layer 146 fills the gap between the light-transmitting glue area 130 and the flexible printed circuit 142. As shown in Figure 2, in some embodiments, the screen-printed insulating adhesive layer 146 will fill all the gaps between the transparent adhesive area 130 and the flexible printed circuit 142, but this is only exemplary, and should not be used This is limited. The screen-printed insulating adhesive layer 146 has a waterproof effect and can protect the flexible printed circuit 142. In some embodiments, the surface impedance of the screen-printed insulating adhesive layer 146 is between 1× ^{10 10} Ω/□ to 1×10 ¹³ Ω/□, so the flexible printed circuit 142 can also be protected in terms of insulation.

In this embodiment, the screen-printed insulating glue layer 146 of the touch module 100 is covered on the flexible printed circuit 142 by screen printing, and the screen-printed insulating glue layer 146 is a cold ultraviolet curing insulating glue. This cold UV curing insulating adhesive is cured by a cold UV curing process, and the temperature range of the cold UV curing process is between 25 ^o C and 50 ^o C. In some embodiments, the screen-printed insulating adhesive layer 146 is a mixture of acrylate oligomer/acryl resin and monomer acrylic resin. In some practical ways, the material of the screen-printed insulating adhesive layer 146 may be a material with transparent insulating properties.

As shown in Figure 2, the screen-printed insulating adhesive layer 146 also has an upper surface 146a, and the surface 146a is flat. Compared with the traditional way of using glue to protect the flexible circuit, the surface 146a of the screen-printed insulating adhesive layer 146 formed by the screen printing method is more uniform and flat, so that the touch structure is improved in the use of space for the protection circuit, thus reducing some types There is a problem that the bare metal circuit cannot be protected due to insufficient space in the touch control structure.

Returning to FIG. 2, the screen-printed insulating adhesive layer 146 has a thickness W1, and the light-transmitting adhesive area 130 has a thickness W2. Wherein, the thickness W1 is between 6 μm and 75 μm, and the thickness W1 is smaller than the thickness W2 of the light-transmitting adhesive area 130, so the upper surface 146a of the screen-printed insulating adhesive layer 146 will not contact the protection board 120. As a result, there will be a gap between the screen-printed insulating adhesive layer 146 and the protective plate 120 to keep them out of contact with each other, and the poor appearance of the dents and the foamy appearance of the protective plate 120 will be improved.

In this embodiment, the touch sensing layer 110 of the touch module 100 is an insulating layer with an indium tin oxide film pattern or a metal mesh pattern. Among them, the indium tin oxide film and the metal mesh film are both transparent conductive films. In some embodiments, conductive films such as the indium tin oxide film and the metal mesh film can respond to changes in the capacitance of the touch sensing layer 110 to generate corresponding electrical signals, and the flexible printed circuit 142 realizes the touch function. When the touch module 100 is applied to a display module, the transparent touch sensing layer 110 will not affect the functions of the display module too much.

FIG. 3 is a schematic diagram showing the structure of the touch module 100 of this embodiment applied to the display module 150. For the structure of the touch module 100 of this embodiment, refer to FIG. 2. According to FIG. 3, the display module 150 is located under the touch sensing layer 110, and is bonded to the touch sensing layer 110 using a full-plane bonding (Diret-bonding) method. In some embodiments, the display module 150 is a liquid crystal display module (LCM) or an organic light emitting diode (OLED). When the full-plane bonding method is used for bonding, the optical transparent glue 152a is used, and the optical transparent glue 152a will not affect the display function of the display module 150 too much.

FIG. 4 is a schematic diagram showing another structure of the touch module 100 of this embodiment applied to the display module 150. The application method in FIG. 4 differs from that in FIG. 3 in the bonding method between the display module 150 and the touch module 100. In FIG. 4, the display module 150 and the touch module 100 are bonded by air-bonding. When using word glue for bonding, the sealant 152b is used, and the sealant 152b will only partially cover the display module 150, instead of using the gap between the display module 150 and the touch module 100 All space.

In this way, according to FIGS. 3 and 4, the touch module 100 of the present disclosure can be applied to the display module 150 to be integrated into a display device with touch function.

Another embodiment of the present disclosure is a method of manufacturing a touch module. This method first provides a touch sensing layer. Subsequently, an optically transparent glue area is formed on the touch sensing layer, and a flexible printed circuit is attached to the touch sensing layer. In some embodiments, the method of attaching the flexible printed circuit to the touch sensing layer is to use a flexible printed circuit on glass (FOG) process. Next, the screen-printed insulating glue layer covers the electrical connection area between the flexible printed circuit and the touch sensing layer, and the insulating glue layer is cured with cold ultraviolet light to make the thickness of the insulating glue layer smaller than the thickness of the optically transparent glue area.

According to the above method of manufacturing a touch module, in some embodiments, the temperature of the step of curing the insulating adhesive layer using cold ultraviolet light is in the range of 25°C to 50°C. In this way, a thickness between 6 microns and 75 microns can be formed on the flexible printed circuit, which is smaller than the thickness of the optical transparent glue. Moreover, the surface of the insulating glue layer is flat.

When using the above-mentioned method of manufacturing a touch module to form a touch module, when other protective plates are to be connected above the touch module, since the thickness of the insulating glue layer is smaller than the thickness of the optically transparent glue area, the insulating glue layer will It does not touch the protection board, and there is a gap between the insulating layer and the protection board, so there will be no problems caused by the traditional use of dispensing to protect flexible printed circuits, such as poor appearance of the protection board dents or foam Poor appearance problem. In addition, since the touch structure has improved the use of space for the protection circuit, the problem that some types of touch structures cannot be protected due to insufficient space is reduced.

The features of several embodiments are described above so that those skilled in the art can better understand the description in various aspects. Those skilled in the art should understand that they can easily use this description as a basis to design or modify other processes and structures to achieve the same purposes or advantages as the embodiments introduced herein. Those skilled in the art should also understand that such an equivalent structure does not depart from the common spirit and scope of this description, and various changes, substitutions or alterations can be made without departing from the spirit and scope of this description.

100: Touch module

110: Touch sensing layer

110a: electrode area

120: protection board

130: Transparent plastic area

142: Flexible printed circuit

142a: Electrical connection area

144: conductive adhesive

146: Screen printing insulating adhesive layer

146a: Surface

150: display module

152a: Optical transparent glue

152b: frame glue

2-2: Line segment

W1: thickness

W2: thickness

The advantages and drawings of the present disclosure should be understood by the following embodiments and with reference to the accompanying drawings. The descriptions of these drawings are only examples of implementations, and therefore should not be considered as limiting individual implementations or limiting the scope of patent applications for inventions. FIG. 1 is a schematic top view of a touch module according to an embodiment of the disclosure. Figure 2 shows a cross-sectional view of Figure 1 along line 2-2. FIG. 3 is a schematic diagram showing the structure of the touch module according to an embodiment of the present disclosure applied to the display module. FIG. 4 is a schematic structural diagram of a touch module according to another embodiment of the present disclosure applied to a display module.

100: Touch module

110: Touch sensing layer

110a: electrode area

120: protection board

130: Transparent plastic area

142: Flexible printed circuit

142a: Electrical connection area

144: viscose

146: Screen printing insulating adhesive layer

146a: Surface

W1, W2: thickness

Claims (10)

A touch module includes: a touch sensing layer with an electrode area; a protection board located above the touch sensing layer; a light-transmitting glue area located between the touch sensing layer and the protection board, The light-transmitting glue area is attached and connected to the touch sensing layer and the protective plate; a flexible printed circuit is located on the touch sensing layer, and an electrical connection area of the flexible printed circuit is electrically attached with a conductive adhesive On the electrode area of the touch sensing layer; and a screen-printed insulating glue layer located on the flexible printed circuit and adjacent to the light-transmitting glue area, and filled in between the light-transmitting glue area and the flexible printed circuit Wherein, the thickness of the screen-printed insulating glue layer is smaller than the thickness of the transparent glue area, and the screen-printed insulating glue layer does not contact the protective plate. The touch module according to claim 1, wherein the touch sensing layer is an insulating layer with an indium tin oxide film pattern or a metal mesh pattern. The touch module according to claim 1, wherein the conductive adhesive is an anisotropic conductive adhesive. The touch module according to claim 1, wherein the screen-printed insulating glue layer is a cold ultraviolet curing insulating glue. The touch module according to claim 4, wherein the thickness of the screen-printed insulating glue layer is between 6 μm and 75 μm, and the thickness of the screen-printed insulating glue layer The thickness is smaller than the thickness of the transparent adhesive area. The touch module according to claim 5, wherein a surface impedance of the screen-printed insulating adhesive layer is between 1x10 ¹⁰ Ω/□ and 1x10 ¹³ Ω/□. The touch module according to claim 1, wherein the protective plate is a cover glass. The touch module according to claim 1, wherein the transparent glue area is an optical transparent glue. A method for manufacturing a touch module includes: providing a touch sensing layer; forming an optically transparent glue area on the touch sensing layer; attaching a flexible printed circuit to a touch sensing layer; screen printing an insulating glue A layer covering the electrical connection area between the flexible printed circuit and the touch sensing layer; curing the insulating adhesive layer with a cold ultraviolet light so that the thickness of the insulating adhesive layer is smaller than the thickness of the optically transparent adhesive area; and providing a The protective plate is attached to the touch sensing layer through the optically transparent adhesive area, and the screen-printed insulating adhesive layer does not contact the protective plate. The method for manufacturing a touch module according to claim 9, wherein a temperature for curing the screen-printed insulating adhesive layer by using the cold ultraviolet light is in a range of 25°C to 50°C.

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