TWI423103B - Molded case with anti - electromagnetic interference and capacitive track plate and its preparation method - Google Patents

Description

Molded case with anti-electromagnetic interference and capacitive track plate function and preparation method thereof

The invention relates to a design of a track plate and a molded case integrally formed, in particular to a molded case which has the functions of preventing electromagnetic interference and a capacitive track plate and a preparation method thereof.

In today's fast-developing technology era, whether it is a notebook computer, mobile phone or other portable electronic devices, it is an inevitable trend to operate with a trackpad (touchpad). However, in the production of a notebook computer, the trackpad is modularized and assembled on the case of the notebook computer. However, this method has many shortcomings. For example, the seam generated after assembly will make it difficult to achieve in the anti-fouling and water-repellent parts, or an additional anti-fouling and water-repellent design or assembly procedure, no matter what method is used. Both will increase the cost and will not completely solve the problem of anti-fouling and water repellent. At the same time, the trackpad module must also consider the relevant standards for preventing electromagnetic interference (EMI). If there is no measures to prevent Electro-Magnetic Interference (EMI), it will not only affect the operation of other electronic devices, but also be susceptible to interference from other electronic devices. At present, the anti-electromagnetic interference method includes metal iron sheet, spray conductive paint, electroplating, magnesium alloy and vacuum sputtering. However, the vacuum sputtering method can coat a thin and average metal film, and the relative anti-EMI effect is better than other methods. In terms of environmental protection, a large amount of chemical agents are required for metal iron sheets, electroplating and conductive paints. The vacuum sputtering method uses physical principles to plate metal atoms on the surface of plastic casings. The process is more environmentally friendly, and the cost is also better than other methods. Low 2~30% is a technology with more potential in the future.

In order to achieve the anti-fouling, water-repellent and anti-electromagnetic interference requirements, and the complexity of the assembly process and related processes, as well as cost control, the present invention proposes an invention in which a molded case and a track plate are integrally formed. concept.

Accordingly, it is an object of the present invention to provide a molded case that has both electromagnetic interference prevention and capacitive trackpad functions.

Another object of the present invention is to provide a method for preparing a molded case which has both the function of preventing electromagnetic interference and the function of a capacitive track plate.

The technical means adopted by the present invention to solve the problems of the prior art is a molded case having both the function of preventing electromagnetic interference and the capacitive track plate, comprising: a substrate having a first surface and a second surface, The first surface defines a touch operation area, and a plurality of first through holes and second through holes are formed at predetermined positions of the touch operation area of the substrate, and the first through holes and the second through holes are a first conductive layer is formed on the first surface of the substrate; the first electrode layer includes a first electrode pattern and a second electrode pattern, wherein the first electrode layer is disposed on the first surface of the substrate The first electrode pattern is electrically connected to the conductive segments of the first through holes, and the second electrode pattern is electrically connected to the conductive segments of the second through holes; a second electrode layer is formed on a second surface of the substrate, the second electrode layer includes a first line and a second line, the first line is electrically connected to the conductive portion of the first through hole to electrically connect the first electrode a first electrode pattern of the layer, and the second line is electrically connected to The second conductive section of the through hole to be electrically connected to the first electrode pattern layer, the second electrode; and a ground layer formed on at least the first or second surface of the substrate.

The above-mentioned plastic shell having the functions of preventing electromagnetic interference and capacitive track plate includes: (a) providing a substrate; (b) opening a plurality of through holes on the substrate; and (c) performing a film The process comprises: forming the first electrode layer on the first surface of the substrate, and forming the second electrode layer on the second surface, and forming the ground layer on at least the first surface or the second surface of the substrate; d) conducting through holes of the substrate to electrically connect the first electrode layer and the second electrode layer.

Through the technical means adopted by the invention, the function of the computer casing and the capacitive track plate can be simultaneously combined, and the track plate is directly formed on the surface of the molded case body and the formation of the ground layer, and the anti-fouling can be combined , water repellent and anti-electromagnetic interference, and will not increase the cost of assembly and process. In the process, only the sputtering can be used to achieve the conduction of the upper and lower circuits, and the steps of filling the silver glue or other conductive glue can be avoided, thereby reducing the defect rate of the product.

The specific embodiments of the present invention will be further described by the following examples and the accompanying drawings.

Please also refer to the first to third figures, which are respectively a perspective view, a top view and a partial cross-sectional view of the first embodiment of the molded case of the present invention. As shown in the figure, the molded case 100 of the present invention having both the function of preventing electromagnetic interference and the capacitive track plate comprises a substrate 1 having a first surface 11 and a second surface 12, and a first surface 11 is defined The touch operation area 111 is provided with a plurality of first through holes 131 and second through holes 132 at predetermined positions of the touch operation area 111 of the substrate 1 . A first electrode layer 2 is formed on the touch operation area 111 of the first surface 11 of the substrate 1, and a second electrode layer 3 is formed on the second surface 12 of the substrate 1 (refer to FIG. 4). And the first through hole 131 and the second through hole 132 of the substrate 1 are provided with a conductive portion 14 (for example, silver paste or a conductive portion 14 formed on the hole wall by sputtering). The first electrode layer 2 and the second electrode layer 3 are electrically connected.

The first electrode layer 2 includes a first electrode pattern 21 and a second electrode pattern 22. The first electrode pattern 21 is in contact with the conductive segments 14 of the first through holes 131, and the second electrode patterns 22 are in contact with the conductive segments 14 of the second through holes 132. In this embodiment, the first electrode pattern 21 is used as the X-axis electrode of the capacitive touch panel, and the second electrode pattern 22 is used as the Y-axis electrode. The shape of the second electrode pattern is square in this embodiment, but is not limited thereto. .

In addition, a ground layer 23 is formed on the first surface 11 of the substrate 1 and away from the touch operation area 111, and is a material having an electromagnetic interference prevention function.

Please also refer to the fourth to fifth figures, which are respectively a perspective view and a bottom view of the first embodiment of the molded case of the present invention. As shown in the figure, the second electrode layer 3 includes a first line 31 and a second line 32. The first line 31 is in contact with the conductive portion 14 of the first through hole 131 to electrically connect the first electrode layer. The first electrode pattern 21 of the second electrode 32 is in contact with the conductive portion 14 of the second through hole 132 to electrically connect the second electrode pattern 22 of the first electrode layer 2. The second line 32 shown in the figure includes a short line portion electrically connecting each adjacent second through hole 132 in addition to the extended long line.

Similarly, a portion of the first line 31 and the second line 32 of the second electrode layer 3 is avoided on the second surface 12 of the substrate 1, and another ground layer 33 is formed, which is also provided with an electromagnetic interference prevention function. Material. The ground layer described in this embodiment may be formed only on a single surface (first surface or second surface) or both surfaces (first surface and second surface) of the substrate, and the occupied area is part or all The area, position, shape, and the like may be determined according to the needs of the product, and are not limited to the manner described in this embodiment.

Further, a connector 4 is formed at a predetermined position of the second surface 12 of the substrate 1, and the integrated first line 31 and a second line 32 can be connected to the circuit board. The molded case 100 described in this embodiment has the function of preventing electromagnetic interference, and has the function of a capacitive track board, and is preferably applied as a track board (touch pad) of a notebook computer, but is not limited thereto.

In terms of process, the thin film process of the first electrode layer 2, the second electrode layer 3, and the ground layers 23, 33 of the molded case 100 can be made by sputtering, for example, at the first of the substrate 1. The surface 11 and the second surface 12 are respectively sputtered to form a metal thin film (copper or stainless steel + copper). The patterning process of the first electrode pattern 21 and the second electrode pattern 22 can be performed by a process such as a mask process or a laser engraving process. For example, the mask process can implement the patterned mask process of the negative film when the film process is not implemented, and the laser engraving process is performed after the film process is performed, and the details of the two processes will be described. This will be explained in the process section described later.

Referring to the sixth figure, it is a schematic diagram of the molded case of the present invention applied to a notebook computer. As shown in the figure, the molded case 100 of the present invention is applied to the notebook computer 5, and can simultaneously function as a computer case and a capacitive track plate, and the integrated molding design can simultaneously have antifouling and water repellent resistance. The function of preventing electromagnetic interference.

Referring to the seventh figure, it is a flow chart of the preparation method of the molded case of the present invention. Please also refer to the eighth embodiment of the present invention, which is a cross-sectional view of a second embodiment of the method for preparing a molded case of the present invention.

First, a substrate is provided (step 101). The substrate 1 has a first surface 11 and a second surface 12 as shown in FIG.

A plurality of through holes are formed in the substrate (step 102). In the figure, only one through hole 133 is taken as an example, as shown in the eighth B. The formation of the through holes 133 includes that it can be completed at the time of injection molding, or can be drilled after the injection. According to the design requirements, the injection molding can first set the hole position and the hole diameter when the through hole is opened, and form a through hole that meets the requirements after one injection molding. If it is drilled, it can be drilled according to the set hole position and hole diameter after injection molding.

Pre-treatment (step 103), including roughing, pre-washing, through-hole micro-etching, substrate cleaning, air knife water removal and baking, etc., to facilitate the subsequent steps.

Performing a thin film process (step 104) to form a first electrode layer 2 on the first surface 11 of the substrate 1 (as shown in FIG. 8C) while avoiding the first electrode layer on the first surface 11 of the substrate 1. In part 2, the ground layer 23 is formed by sputtering or coating. Next, a second electrode layer 3 is formed on the second surface 12 (as shown in FIG. 8D) while the portion of the second electrode layer 3 is avoided on the second surface 12 of the substrate 1, and the ground layer 33 is formed in the same manner. Wherein, the formation of the electrode layer includes, in practice, a mask process or a laser engraving process. The formation of the ground layer may be formed only on a single surface (first surface or second surface) or both surfaces (first surface and second surface) of the substrate, wherein the ground layer 23 formed on the first surface 11 Mainly related to touch interference signal prevention, and the ground layer 33 formed by the second surface 12 is related to electromagnetic wave prevention, but both are achieved by the principle of grounding, and the occupied area is part or all of the area. The position, shape, and the like may be determined according to the needs of the product, and are not limited to the manner described in this embodiment.

When using the mask process, a mask can be made before sputtering, for example, by photoresist coating or screen printing, and the two sides are subjected to a film coating operation, and after the sputtering is completed, the mask is removed. Membrane operation (extraction or washing).

In the laser engraving process, the substrate 1 can be subjected to double-sided film plating, and the two sides are engraved according to the desired electrode pattern by laser engraving to remove the debris.

Each of the through holes on the substrate is turned on (step 105), and the first electrode layer 2 and the second electrode layer 3 are electrically connected. In this embodiment, the conductive paste (silver glue)/pulp material is covered with a printed cover. The surface of the substrate of the cover is filled with the conductive paste/slurry into the through hole 133, and then baked, and finally the conductive portion 14 is formed on the hole wall of the through hole 133. Those skilled in the art will recognize that this step can also be performed prior to performing step 104. That is, after the conductive paste/slurry is poured into the through hole 133, the film process of the step 104 is performed, and the first electrode layer 2 and the second electrode layer 3 are electrically connected.

At the same time, after the above steps are completed, it is more necessary to incorporate a connector (not shown) at a suitable position of the molded case to integrate the circuits on the substrate.

Referring to Figures 9A-IXD, which are cross-sectional views of a third embodiment of the method of making a molded case of the present invention. The preparation process of this embodiment is similar to that of the second embodiment, so the similarities are not repeated here. Referring to the ninth C, the main difference is that in the embodiment, when the thin film process (step 104) is performed, the first electrode layer 2 is partially extended to the apertures of the through holes 133. Next, as shown in the ninth D, the second electrode layer 3 is partially extended to the aperture of the through hole 133, and the first electrode layer 2 and the second electrode layer 3 are contacted and electrically connected. In this way, it is not necessary to fill the conductive paste or other conductive material to achieve the conduction of the upper and lower circuits. The other steps are similar to the second embodiment and will not be described again.

It can be seen from the above embodiments that the molded case and the preparation method thereof, which have the functions of preventing electromagnetic interference and capacitive track plate, have industrial value, but the above description is only preferred of the present invention. It is to be understood that those skilled in the art will be able to make various other modifications in accordance with the above description, but such changes are still within the spirit of the invention and the scope of the invention as defined below.

100. . . Molded case

1. . . Substrate

11. . . First surface

111. . . Touch operating area

12. . . Second surface

131. . . First consistent hole

132. . . Second through hole

133. . . Through hole

14. . . Conductive section

2. . . First electrode layer

twenty one. . . First electrode pattern

twenty two. . . Second electrode pattern

twenty three. . . Ground plane

3. . . Second electrode layer

31. . . First line

32. . . Second line

33. . . Ground plane

4. . . Connector

5. . . Notebook computer

The first figure is a perspective view of a first embodiment of a molded case of the present invention, mainly showing a first electrode layer on a first surface of the molded case;

2 is a top view of a first embodiment of a molded case of the present invention, mainly showing a first electrode layer on a first surface of the molded case;

The third figure is a partial cross-sectional view of the molded case of the present invention;

4 is a perspective view of a first embodiment of a molded case of the present invention, mainly showing a second electrode layer on a second surface of the molded case;

Figure 5 is a bottom view of the first embodiment of the molded case of the present invention, mainly showing the second electrode layer on the second surface of the molded case;

Figure 6 is a schematic view showing the application of the molded case of the present invention to a notebook computer;

7 is a flow chart of a method for preparing a molded case of the present invention;

8A to 8E are cross-sectional views showing a second embodiment of preparing a molded case of the present invention;

The ninth A-ninth D is a cross-sectional view showing a third embodiment of the molded case of the present invention.

100. . . Molded case

1. . . Substrate

11. . . First surface

111. . . Touch operating area

12. . . Second surface

131. . . First consistent hole

132. . . Second through hole

2. . . First electrode layer

twenty one. . . First electrode pattern

twenty two. . . Second electrode pattern

twenty three. . . Ground plane

33. . . Ground plane

Claims (12)

A molded case having both a function of preventing electromagnetic interference and a capacitive track plate, comprising: a substrate having a first surface and a second surface, the first surface defining a touch operation area, and the substrate a plurality of first through holes and second through holes are defined in a predetermined position of the touch operation area, and the first through holes and the second through holes are distributed with a conductive portion; a first electrode layer is formed The first electrode layer includes a first electrode pattern and a second electrode pattern, wherein the first electrode pattern is electrically connected to the first through holes in the touch operation area of the first surface of the substrate. a conductive segment, wherein the second electrode pattern is electrically connected to the conductive segments of the second through holes; a second electrode layer is formed on the second surface of the substrate, and the second electrode layer includes a first electrode a first line electrically connected to the conductive portion of the first through hole to electrically connect the first electrode pattern of the first electrode layer, and the second line is electrically connected Conducting a conductive segment of the second via to electrically connect the second electrode of the first electrode layer Electrode pattern; a ground layer, is formed to avoid the line portion of the second electrode layer at least at the time of the first line of the surface of the substrate to avoid the portion of the first electrode layer or the second surface. The molded case according to claim 1, wherein the first through hole and the conductive portion in the second through hole are a silver paste. The molded case according to claim 1, wherein the first through hole and the conductive portion of the second through hole are partially extended from the first electrode layer and the second electrode layer to the first through The hole and the hole of the second through hole are formed. The molded case according to claim 1, wherein a connector is formed at a predetermined position of the second surface of the substrate. The invention relates to a method for preparing a molded case which has the functions of preventing electromagnetic interference and a capacitive track plate, which is used for preparing the molded case according to claim 1, wherein the steps include: (a) providing a substrate; (b) forming a plurality of through holes on the substrate; (c) performing a thin film process of forming the first electrode layer on the first surface of the substrate and forming the second electrode layer on the second surface, At the same time, when the ground layer is formed on at least the first surface of the substrate, the portion of the first electrode layer or the second surface is avoided to avoid the portion of the second electrode layer; (d) the substrate is turned on. Each of the through holes electrically connects the first electrode layer and the second electrode layer. The molded case according to claim 5, wherein after the step (b), the substrate is further subjected to roughening, pre-washing, through-hole micro-etching, substrate cleaning, air knife water removal and baking. deal with. The molded case according to claim 5, wherein the step (c) forms the first electrode layer, the second electrode layer and the ground layer by using a mask process. The molded case according to claim 5, wherein the step (c) forms the first electrode layer, the second electrode layer and the ground layer by using a laser engraving process. The molded case according to claim 5, wherein the step (d) is partially extended to the hole wall of each of the through holes when the first electrode layer and the second electrode layer are formed in the step (c) The first electrode layer and the second electrode layer are brought into contact and electrically connected. The molded case according to claim 5, wherein the step (d) is filled with a silver paste in each of the through holes to electrically connect the first electrode layer and the second electrode layer. The molded case of claim 5, wherein the step (d) further comprises bonding a connector at a predetermined position of the molded case. The invention relates to a method for preparing a molded case which has the functions of preventing electromagnetic interference and a capacitive track plate, and is used for preparing the molded case according to claim 1, wherein the steps include: (a) providing a substrate; (b Opening a plurality of through holes on the substrate; (d) conducting a through hole of the substrate by using a conductive material; (c) performing a thin film process of forming the first electrode layer on the first surface of the substrate, forming the second electrode layer on the second surface, and forming the ground layer on at least the first surface of the substrate When the portion of the first electrode layer or the second surface is avoided, the portion of the second electrode layer is avoided.