JPH10135683A - Conductive tape and liq. crystal display, using the tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely ground a drive circuit board and metal frame and prevent the structural restriction on grounded parts by providing a first conductor on a nonadhesive surface of a conductive tape and second conductor and insulator alternately on an adhesive surface of the tape. SOLUTION: A second conductor 2 has adhesive materials at both surfaces. An insulator 3 has adhesive materials at both surfaces. The adhesive material 5 is an adhesive layer for adhering the second conductor 2 and the insulator 3 to a first conductor 1. The adhesive material 7 is an adhesive layer for adhering a conductive tape to specified position. By adhering to specified position of a drive circuit board, the connection between a conductive ground pad and second conductor and connection between a metal frame housing a liq. crystal panel and first conductor can be easily and surely made.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive tape used for a shield measure of a liquid crystal display device used for AV equipment, OA equipment, portable information terminal equipment and the like, and a liquid crystal display device using the same.

[0002]

2. Description of the Related Art In a conventional liquid crystal display device, handling is facilitated by supporting a liquid crystal panel together with a peripheral driving circuit board and an illuminating means on a rear surface with a frame from the upper and lower sides of the liquid crystal panel. Had been formed. The drive circuit board supports a liquid crystal drive element and is connected to the liquid crystal panel.

In such a liquid crystal display device,
Conventionally, in order to prevent the liquid crystal display device from malfunctioning due to external electromagnetic influence, the frame on the upper surface side or the lower surface side is conventionally formed as a metal frame, and the drive circuit board and the metal frame are electrically connected. By doing so, the metal frame and the drive circuit board are grounded.

There are various methods for grounding the metal frame and the drive circuit board. Generally, a ground pad is provided on the drive circuit board, and the upper or lower frame body is screwed. When stopping and fixing, the screw was designed to penetrate the earth pad.

In Japanese Unexamined Patent Publication No. Hei 7-248481, as shown in FIG. 10, a ground connector 16 is formed on the drive circuit board 15, and a socket 18 serving as a ground terminal is provided in a part of the metal frame 17 itself. Forming the socket 18
There is disclosed a technique for fitting the wire to the ground connector 16.

Further, in Japanese Patent Application Laid-Open No. 7-281204, as shown in FIG. 11, a conductive foil 19 which is soldered to the drive circuit board 15, folded and screwed to a metal frame 17 is provided. A technique for connecting the drive circuit board 15 and the metal frame 17 with a foil 19 is disclosed. In this publication, as shown in FIG. 12, an earth pad provided on the drive circuit board 15 is exposed, and an elastic conductive material 20 is interposed in a gap between the drive circuit board 15 and the metal frame 17. Techniques are disclosed.

[0007]

However, the above-mentioned prior art has the following problems.

First, in the case where the grounding is performed by passing a screw through the grounding pad, stress is concentrated near the screw fixing of the grounding pad, so that the conductor is likely to be broken near the screw fixing. there were. In particular, in recent years, many frame-reduction type liquid crystal display devices have been developed. However, if the drive circuit board becomes smaller due to the reduction of the frame, it is difficult to provide a screw hole in the drive circuit board. It was not a suitable method.

In the technique disclosed in Japanese Patent Application Laid-Open No. Hei 7-248481, the relative positional relationship between the socket provided on the metal frame and the connector provided on the drive circuit board is fixed. However, there are problems that the structure is subject to many restrictions and the cost is increased as the number of parts increases.

In the technique disclosed in Japanese Patent Application Laid-Open No. 7-281204, when the folded conductive foil is used, the metal foil is bent to connect the drive circuit board and the metal frame, so that the metal foil is folded. To take time,
Since the metal foil is connected to the drive circuit board by soldering, conductive foreign substances such as solder balls are likely to be generated, and it is necessary to reheat the solder connection part during repair, so that the circuit pattern peels. There is a problem that it may occur.

Further, among the techniques disclosed in the publication, when an elastic conductive material is used, it is necessary to provide a place for contacting the conductive material on the drive circuit board. There was a problem that the substrate had to be large.

The present invention has been made in view of the above-described problems, and has assured grounding of a drive circuit board and a metal frame, and can be easily repaired without being restricted by a structural limitation at a grounding position. Another object of the present invention is to provide a conductive tape for grounding the drive circuit board and the metal frame without increasing the size of the drive circuit board, and a liquid crystal display device using the same.

[0013]

According to a first aspect of the present invention, there is provided a conductive tape which has an adhesive surface and a non-adhesive surface, and is used for establishing conduction between different places. The first conductor is provided on the non-adhesive surface, and the second conductor and the insulator are alternately provided on the adhesive surface of the conductive tape.

A conductive tape according to a second aspect of the present invention is the conductive tape according to the first aspect, wherein a concave portion is formed in a portion of the first conductor corresponding to the second conductor. It is characterized by having.

A conductive tape according to a third aspect of the present invention is the conductive tape according to the second aspect, wherein a cushioning material is provided on the recess.

A conductive tape according to a fourth aspect of the present invention is the conductive tape according to the third aspect, wherein the cushioning member is made of a color different from that of the first conductor.

According to a fifth aspect of the present invention, there is provided a liquid crystal display device comprising:
A liquid crystal display device comprising a liquid crystal panel having a drive circuit board provided with a conductive ground pad provided in a metal frame, wherein the drive circuit board and the metal frame are formed using the conductive tape according to claim 1. Are connected.

The operation of the above configuration will be described below.

The conductive tape of the present invention is a conductive tape for establishing conduction between different places, a first conductor is provided on a non-adhesive surface of the conductive tape, and an adhesive surface of the conductive tape is provided on an adhesive surface of the conductive tape. Since the second conductor and the insulator are provided alternately, the second conductor and the insulator are attached to a predetermined position of the drive circuit board provided with the conductive ground pad, for example, so that the conductive ground pad and the conductive ground pad of the drive circuit board are provided. The connection with the second conductor and the connection between the metal frame for accommodating the liquid crystal panel and the first conductor can be easily and reliably performed.

Further, by forming a concave depression in a portion of the first conductor corresponding to the second conductor, the second conductor is pressed against the drive circuit board by the depression. The drive circuit board and the second
Can be more reliably connected to the conductor.

Further, by providing a buffer material on the recess, the buffer material can press the second conductor against the drive circuit board, and the drive circuit board and the second conductor can be pressed. Connection can be made more reliably.

Further, by making the cushioning material a color different from that of the first conductor, when the conductive tape is attached to the drive circuit board, the conductive ground pad of the drive circuit board and the conductive tape can be used. The alignment with the second conductor can be easily performed by looking at the conductive earth pad of the drive circuit board and the cushioning material.

In the liquid crystal display device of the present invention, the drive circuit board and the metal frame are connected to each other by using the conductive tape according to any one of the first to fourth aspects. The ground connection can be easily and reliably performed without increasing the cost, and it is possible to obtain a liquid crystal display device with high shielding measures.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is a perspective view showing a conductive tape according to the present embodiment. FIG. 2 (a) is a sectional view taken along the line AA in FIG. 1, and FIG. 1 is a sectional view taken along line BB in FIG. 1, and FIG. 2C is a sectional view taken along line CC in FIG. 1 and 2, reference numeral 1 denotes a first conductor, 2
Is a second conductor, and 3 is an insulator. As the first conductor 1, a material having high conductivity such as a copper foil can be used. The second conductor 2 may be a mesh-like cloth to which copper powder is adhered. Further, as the insulator 3, a PET film or the like can be used.

As shown in FIG. 2A, adhesives 5 and 7 are provided on both surfaces of the second conductor 2, and both surfaces of the insulator 3 are shown in FIG. As shown in FIG. 2, the adhesive materials 5 and 7 are provided. With such a structure, the adhesive 5 serves as an adhesive layer for bonding the second conductor 2 and the insulator 3 to the first conductor 1 as shown in FIG. 2C. The adhesive 7 serves as an adhesive layer for attaching the conductive tape to a predetermined position. Therefore, the conductive tape of the present invention can be used as the adhesive 7
The side is an adhesive surface, and the first conductor 1 side is a non-adhesive surface. The adhesives 5 and 7 have conductivity.
In this embodiment, an adhesive resin containing conductive particles is used.

Further, a concave portion is provided in a portion of the first conductor 1 corresponding to the second conductor 2, and when the conductive tape is attached to a drive circuit board,
The second conductor 2 is pressed against the drive circuit board by the depression.

The conductive tape can be manufactured as follows. First, as shown in FIG. 3A, a first conductor 1 made of a copper foil sheet is provided with adhesives 5 and 7 on its upper and lower surfaces. Are affixed to predetermined positions, respectively. In the present embodiment, 14-40 manufactured by Hitachi, Ltd. is used as the adhesive 5.
0-50 is used as the adhesive 7 as Y94 manufactured by Sumitomo 3M.
48S is used as the second conductor 2 by X70 manufactured by Sumitomo 3M.
01, PET # 1 manufactured by Diafoil Co., Ltd. as the insulator 3
00S-100 was used for each. At this time, the second conductor 2 having a thickness smaller than that of the insulator 3 is used. In addition, the said adhesive material 5 is the first
May be provided on the conductor 1.

Thereafter, as shown in FIG.
The adhesive 7 side is attached to a release paper 8 of the same size or larger than the first conductor 1. In the present embodiment, the release paper 8 is made of paper coated with silicon.

At this time, since the thickness of the second conductor 2 is smaller than the thickness of the insulator 3, as shown in FIG. The second conductor 2 is pushed in by, for example, and the entire surface of the adhesive 7 is adhered to the release paper 8, and a portion of the first conductor 1 corresponding to the upper surface of the second conductor 2 is pressed. A concave recess is provided, and the sectional shape is as shown in FIG.

As shown in FIG. 4, the conductive tape formed on the release paper 8 is formed on the conductive tape formed on the release paper 8 based on a predetermined size. If a cut line 12 is provided from the top to just before the release paper 8, and the sections separated by the cut line 12 can be individually peeled off from the release paper, the conductive line can be made as necessary along the cut line 12 as necessary. The tape can be peeled and used, making it very easy to handle.

As shown in FIG. 5, the conductive tape of the present embodiment has a structure in which the second conductor 2 is
The connection between the drive circuit board 9 and the conductive tape is performed by attaching the conductive tape to the conductive earth pad 10 provided on the substrate. At this time, the second conductive member 2 is provided on the drive circuit board 9 by providing a concave depression in a portion of the first conductive member 1 corresponding to the second conductive member 2 of the conductive tape. Ground pad for conductive 1
Since the contact is made so as to be pressed to 0, the connection between the second conductor 2 and the grounding pad 10 for conduction can be reliably performed.

In the present embodiment, in a drive circuit board composed of a multi-layer circuit board in which the uppermost layer is covered with an insulating film, for example, a part of the insulating film on the power supply line is peeled off to remove one of the power supply lines. The exposed portion was used as the conductive ground pad 10.

After the conductive tape of the present embodiment is attached to the drive circuit board of the liquid crystal panel, when the plastic chassis, the lens sheet, the liquid crystal panel, and the metal frame 13 are superimposed in this order as shown in FIG. The first conductor 1 of the conductive tape affixed to the drive circuit board 9 provided on the liquid crystal panel comes into contact with the metal frame 13 over a wide area, thereby connecting the conductive tape to the metal frame 13. Can be performed reliably. In FIG. 6, a drive circuit board 9 includes a drive circuit board 9a provided above and below the liquid crystal panel, and a drive circuit board 9 provided on the left side of the liquid crystal panel.
In this embodiment, a conductive tape is attached to the drive circuit board 9a to electrically connect the drive circuit board 9a and the drive circuit board 9b. In the figure, reference numeral 14 denotes a black insulating tape.

In the liquid crystal display device using the conductive tape according to the present embodiment, the reliability against external static electricity and electromagnetism is improved, and malfunction does not occur.

(Embodiment 2) FIG. 7 is a perspective view showing a conductive tape according to this embodiment. FIG. 8A is a sectional view taken along the line AA in FIG. 1, and FIG. FIG. 8C is a cross-sectional view taken along a line CC in FIG. 1. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As can be seen from FIGS. 7 and 8, the structure of the conductive tape according to the present embodiment is substantially the same as that of the first embodiment, but the concave shape provided on the first conductor 1 is not shown. The difference is that the cushioning material 4 is provided on the depression. In the present embodiment, a resin having elasticity is used as the cushioning material 4.

The conductive tape can be manufactured as follows. First, as shown in FIG. 9A, a first conductor 1 made of a copper foil sheet is provided with a second conductor 2 and an insulator 3 provided with adhesives 5 and 7 on upper and lower surfaces. Are affixed to predetermined positions, respectively. The adhesives 5 and 7, the second conductor 2, and the insulator 3 are:
The same material as in Embodiment 1 was used. At this time, the second
The conductor 2 having a thickness smaller than the thickness of the insulator 3 is used. The adhesive 5 may be provided on the first conductor 1 in advance.

Thereafter, as shown in FIG. 9B,
Similarly to the first embodiment, the adhesive 7 is attached to a release paper 8 having the same size as or larger than the first conductor 1.

At this time, since the thickness of the second conductor 2 is smaller than the thickness of the insulator 3, as shown in FIG. The second conductor 2 is pushed in by, for example, and the entire surface of the adhesive 7 is adhered to the release paper 8, and a portion of the first conductor 1 corresponding to the upper surface of the second conductor 2 is pressed. A concave depression is provided.

Further, as shown in FIG. 9 (d), a cushioning material 4 is attached to a concave recess provided in the first conductor 1, and the cross-sectional shape is as shown in FIG. 9 (e). I do. At this time, the thickness of the cushioning material 4 is set to a thickness that can ensure the connection between the second conductor 2 and the conductive earth pad provided on the drive circuit board, for example, the first material. The depth is the same as or slightly larger than the depth of the concave depression provided in the conductor 1.

With respect to the conductive tape manufactured in this manner, as shown in FIG.
A cut line 12 is provided on the conductive tape formed on the release paper 8 from above the first conductor 1 to just before the release paper 8 based on a predetermined size, and a portion divided by the cut line 12 is provided. Can be individually peeled from the release paper, if necessary, the conductive tape can be peeled and used along the cut line 12 as needed, and the handling becomes very easy.

The conductive tape according to the present embodiment has a cushioning material 4 on the concave recess provided in the first conductor 1.
Is provided, the connection between the second conductor 2 and the conductive earth pad provided on the drive circuit board can be performed more reliably.

The cushioning member 4 may be made of, for example, a black material in order to easily distinguish it from other parts. At this time, since the position of the cushioning member 4 can be easily recognized, when attaching the conductive tape to the driving circuit board, the cushioning member 4 and the conductive ground pad provided on the driving circuit board are aligned. Thus, it is possible to prevent a displacement during bonding.

In the liquid crystal display device using the conductive tape according to the present embodiment, the reliability against external static electricity and electromagnetism is improved, and malfunction does not occur.

[0046]

As described above, in the conductive tape of the present invention, the first conductor is provided on the non-adhesive surface, and the second conductor and the insulator are alternately provided on the adhesive surface. The liquid crystal panel is attached to a predetermined position on a drive circuit board of the liquid crystal panel, so that the connection between the drive circuit board and the second conductor, and a metal frame containing the liquid crystal panel and the first conductor Connection can be easily and reliably performed.

Therefore, there is an effect that the conductor can be reliably grounded without inducing disconnection of the conductor as in the case of grounding with screws. In addition, since it is fixed to the drive circuit by an adhesive instead of solder connection, there is no generation of conductive foreign matter such as a solder ball, and an effect that the connection can be easily performed even during repair. Furthermore, there is an effect that shield measures can be performed on the drive circuit board having the conductive ground pad using the conductive tape of the present invention without being restricted by the structure.

Further, by forming a concave depression in a portion of the first conductor corresponding to the second conductor, the second conductor is pressed against the drive circuit board by the depression. The drive circuit board and the second
This has the effect that the connection with the conductor can be made more reliably.

Further, by providing a buffer material on the recess, the buffer material can press the second conductor against the drive circuit board, and the drive circuit board and the second conductor can be pressed. It is possible to achieve a more reliable connection.

Further, by making the buffer material a color different from that of the first conductor, when the conductive tape is attached to the drive circuit board, the conductive ground pad of the drive circuit board and the conductive tape can be used. There is an effect that the alignment with the second conductor can be easily performed by looking at the conductive earth pad of the drive circuit board and the cushioning material.

In the liquid crystal display device of the present invention, since the drive circuit board and the metal frame are connected using the conductive tape according to any one of claims 1 to 4, the number of parts is increased due to the ground connection. It is possible to easily and reliably perform the ground connection without increasing the cost, and it is possible to obtain a liquid crystal display device having high reliability in shielding measures.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a conductive tape of the present invention.

FIG. 2 is a cross-sectional view of the conductive tape shown in FIG.

FIG. 3 is a flowchart showing a process of manufacturing the conductive tape of the present invention.

FIG. 4 is a diagram in which a cut line is provided in the conductive tape of the present invention.

FIG. 5 is a diagram showing a state of connection between the conductive tape of the present invention and a drive circuit board.

FIG. 6 is a view showing a state of connection between the conductive tape of the present invention and a metal frame.

FIG. 7 is a perspective view showing a conductive tape according to another embodiment of the present invention.

8 is a cross-sectional view of the conductive tape shown in FIG.

FIG. 9 is a flowchart showing a process of manufacturing a conductive tape according to another embodiment of the present invention.

FIG. 10 is a diagram showing a state of connection between a drive circuit board and a metal frame in a conventional technique.

FIG. 11 is a diagram showing a state of connection between a drive circuit board and a metal frame in a conventional technique.

FIG. 12 is a diagram showing a state of connection between a drive circuit board and a metal frame in a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st conductor 2 2nd conductor 3 Insulator 4 Buffer material 5 Adhesive material 7 Adhesive material 8 Release paper 9 Drive circuit board 10 Grounding pad 11 Mold 12 Cut line 13 Metal frame 14 Insulation tape

Claims (5)

[Claims] Claims: 1. A conductive tape having an adhesive surface and a non-adhesive surface, for establishing conduction between different places, wherein a first conductor is provided on the non-adhesive surface of the conductive tape,
A conductive tape, wherein a second conductor and an insulator are alternately provided on the adhesive surface of the conductive tape. 2. The conductive tape according to claim 1, wherein a concave portion is formed in a portion of the first conductor corresponding to the second conductor. 3. The conductive tape according to claim 2, wherein a cushioning material is provided on the depression. 4. The conductive tape according to claim 3, wherein the cushioning material has a color different from that of the first conductor. 5. A liquid crystal display device comprising a liquid crystal panel having a drive circuit board provided with a conductive ground pad in a metal frame, wherein the drive circuit board is formed using the conductive tape according to claim 1. And the metal frame is connected to the liquid crystal display device.