JPS6155629A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To heighten the reliability of connection between terminals by making the connection of an electric connecting member and a circuit terminal by solder and connecting the electric connecting member and an element terminal by forming a conductive adhesive on the circuit and connecting the element terminal by using the adhesive. CONSTITUTION:The electric connecting member 20 of a liquid crystal display unit that connects a circuit terminal 24 of a printed board 23 for driving circuit and the element terminal 26 of a liquid crystal display element 25 by the electric connecting member 20 and a circuit terminal 24 are connected by solder, and the electric connecting member 20 are connected by forming a conductive adhesive 30 on the circuit 28 and using the adhesive. Thus, the connection of the electric connecting member 20 and circuit terminal 24 is plated on the circuit 28 and connected with the circuit terminal by solder. Connection of the electric connecting member 20 and element terminal 26 is made by forming the conductive adhesive on the circuit 28 and forming an insulating adhesive 31 between the circuit 28 and using the adhesive for connecting the element terminal 26. Thus, the reliability of connection is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a liquid crystal display device, and particularly to an electrical connection structure between a printed circuit board for a drive circuit and a liquid crystal display element.

[Background of the invention]

Conventionally, the zebra-shaped rubber shown in FIG. The connector 1 and the heat seal type connector 4 shown in FIG. 2 are most widely used.

A zebra-shaped rubber connector 1 shown in FIG. 1 has conductor portions 2 and insulating portions 3 formed alternately. However, this structure
As liquid crystal display elements become larger and the number of terminals increases, the terminal pitch becomes narrower, and contact between the terminals becomes a problem. Currently, the terminals have a width of 0°25m and a pitch of 0.5m.
There are x types, and there is a high possibility that they will become even thinner and finer in the future.

The heat seal type connector 4 shown in Fig. 2 is usually made of PET.
A conductor part 6 and an insulating part 7 are formed by printing on a substrate material 5 such as C. The conductor portion 6 is made of a hot melt resin 9 containing carbon on a thermosetting resin 8 containing carbon, and the insulating portion 7 is made of a hot melt insulating resin. In this way, since hot melt type adhesive is used for the conductor portion 6 and the insulating portion 7, they can be bonded to a liquid crystal display element or a printed circuit board.

On the other hand, the circuit terminals of the printed circuit board have the structure shown in Figure 3! l: There is a structure shown in FIG. In the structure shown in Figure 3, an adhesive layer 11 is formed on a printed circuit board 10 made of glass, epoxy, etc.

Copper foil 12 is pasted together by rolling or electrolysis, unnecessary parts of copper foil 12 are removed by etching to form a circuit section, and copper plating 13, nickel or gold plating 14 is applied on copper foil 12. In the structure shown in FIG. 4, a resist portion 15 is formed by printing, photoresist, etc. on a portion of the printed circuit board 10 outside the circuit portion, and the circuit portion is plated with copper.
3. Nickel or gold plating 14 is formed.

As described above, there are circuit terminals of printed circuit boards in which the level difference between the circuit portion and the insulating portion outside the circuit is large, as shown in FIG. 3, and small as shown in FIG. 4. Therefore, when connecting the heat seal type connector 4 shown in Fig. 2 to the circuit terminals of a printed circuit board, if the height difference is large as shown in Fig. 3, the pitch between the terminals may be particularly narrow. The sealed connector 4 is deformed as shown in FIG. 5, and the Hola L-melt adhesive of the insulating portion 7 does not adhere reliably. For this reason, there is a problem in that the heat seal type connector 4 cannot be used in common with circuit terminals f of different types of printed circuit boards.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide circuit terminals and liquids for printed circuit boards.

[Summary of the invention]

In order to achieve the above object, the present invention connects an electrical connection member and a circuit terminal by soldering, and connects an electrical connection member and an element terminal by forming a conductive adhesive on the circuit. It is characterized in that it is connected to the element terminal with an adhesive.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 6 to 9. 6 is a plan view of the electrical connection member 20, FIG. 7 is a plan view of the connection portion 21 with the circuit terminal, FIG. 8 is a printed view of the connection portion 22 with the element terminal, and FIG. 9 is a printed circuit board. 23 is an explanatory diagram showing a state in which the electrical connection member 20 is connected to the circuit terminal 24 of the liquid crystal display element 23 and the element terminal 26 of the liquid crystal display element 25. FIG.

The electrical connection member 20 is made by laminating a copper foil 28 to a polyimide film 27, printing a resist material on the copper foil 28, and etching the copper foil 28 into stripes or a desired shape. It is formed into a circuit. Further, the connection portion 21 to the circuit terminal 24 of the printed circuit board 23 is formed by forming nickel or gold plating 29 on a copper foil 28 as in the conventional case.

The connection part 22 of the liquid crystal display element 25 with the element terminal 26 is formed by forming a conductive adhesive 30 made of hot melt resin containing carbon on the copper foil 28, and insulating the insulating part between the copper foils 28 made of hot melt resin. An adhesive 31 is formed. Then, a connecting portion 21 with the circuit terminal 24 and the element terminal 26 is provided.
．． Except for 22, the insulating layer 32 is formed by pasting an insulating film or applying a truder resist by printing.

Connection portion 21 of electrical connection member 20 formed in this way
is connected to the circuit terminal 24 of the printed circuit board 23 using solder. Further, in the connection portion 22 of the electrical connection member 20, the conductive portion is heat-bonded with a conductive adhesive 30, and the insulating portion is heat-bonded with a highly insulating insulating adhesive 31f.

FIG. 10 shows another embodiment of the invention. Since the electrical connection member 20 according to the first embodiment has the connection portion on the same surface, it is necessary to bend it into a three-shape as shown in FIG.

The electrical connection member 20 of this embodiment has through-hole wiring, circuits are formed on the front and back sides, and the through-hole portions 33 are plated with copper for through-holes. When formed in this manner, it is sufficient to simply bend the wire once in a U-shape, thereby improving the reliability of the bending.

In each of the above embodiments #, in order to create solder escape when the circuit terminal 24 of the printed circuit board 23 and the connection part 21 of the electrical connection member 20 are connected using solder, the insulation of the connection part 2 is If a hole or notch is provided in the section, solder connection can be made better. Further, as a connection between the connecting portion 22 and the element terminal 26 of the liquid crystal display element 25, it is preferable to use an anisotropic conductor or a lid.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the connecting portion of the electrical connecting member to the circuit terminal is plated on the circuit and connected to the circuit terminal by soldering, and the connecting portion of the electrical connecting member to the element terminal is plated on the circuit and connected to the circuit terminal by soldering. Since the connecting portion is connected to the element terminal using a conductive adhesive on the circuit and an insulating adhesive between the circuits, the reliability of the connection is improved.

[Brief explanation of the drawing]

Figure 1 is a side view of a conventional zebra-shaped connector, Figure 2 is a conventional heat-sealed connector, (a) is a side view, tblii enlarged sectional view, Figures 3 and 4 are 5 is a cross-sectional view of the circuit terminal of the printed circuit board, and FIG. 5 is an explanation to explain the problem when the heat 7-hole type connector shown in FIG. 2 is connected to the circuit terminal of the printed circuit board shown in FIG. 3. 6 is a plan view of an electrical connection member showing a simple embodiment of the present invention, FIG. 7 is an enlarged plan view of the lol path terminal terminal connection portion in FIG. 6, and FIG. An enlarged perspective view of the connecting portion with the terminal, FIG. 9, and FIG. 10 are explanatory diagrams showing the state of connection to the desk. 20... Electrical connection member, 21. 22 - Connection part, 23... Printed circuit board, 24... Circuit terminal,
25...Liquid crystal display element, 26...Element terminal,
28...Copper foil (circuit), 29...Plating, 3
0... Conductive adhesive, 31... Insulating adhesive. Figure 1 Figure 2 (G) Figure 3 Figure 4 Figure 5 Figure 6 Figure 2゜Figure 7 Figure 8

Claims (1)

[Claims] In a liquid crystal display device in which a circuit terminal of a printed circuit board for a drive circuit and an element terminal of a liquid crystal display element are connected by an electrical connection member, the connection between the electrical connection member and the circuit terminal is performed by soldering, and A liquid crystal display device characterized in that the electrical connection member and the element terminal are connected to each other by forming a conductive adhesive on the circuit and connecting to the element terminal with the adhesive.