JPH05100238A - Packaging structure for liquid crystal panel - Google Patents

Abstract

PURPOSE:To obtain the packaging structure for a liquid crystal panel which maintains the reliability on connection over a long period of time and can be reduced in packaging area by improving the strength of adhesion of the liquid crystal panel and a flexible circuit board. CONSTITUTION:In the connecting structure of the liquid crystal panel 1 for connecting a part of circuit patterns 4 of the flexible circuit board 3 to leader terminals 2 of electrodes for driving the liquid crystal panel 1 by using adhesive 5, such as anisotropy conductive adhesive or anisotropy conductive film; this packaging structure for the liquid crystal panel is constituted by disposing an adhesive longer by 0.1 to 1.5mm than the connecting width when the connecting width of the flexible circuit board 3 and the liquid crystal panel is 0.2 to 2.5mm so that the adhesive is made to flow by the heat of a tool 6 for heating and pressurizing and is cured by stagnating in the juncture between the flexible circuit board 3 and the liquid crystal panel 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel mounting structure, and more particularly to an improvement in a liquid crystal panel connection structure.

[0002]

2. Description of the Related Art There are many methods for mounting a liquid crystal panel using a flexible circuit board.
There is a mounting method using an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film.

FIG. 3 is an enlarged schematic view of a main part for explaining a mounting method using an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film. The method of connecting the substrate and the liquid crystal panel has a structure as shown in FIG. Reference numeral 11 is a liquid crystal panel, 12 is a lead terminal of an electrode for driving the liquid crystal panel 11, 13 is a substrate made of an insulating material such as a flexible circuit board, 14 is a circuit pattern on the flexible circuit board 13, and 15 is a lead on the liquid crystal panel 11. It is an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film for connecting the terminal 12 and a part of the circuit pattern 14 on the flexible circuit board 13.

Next, a method of mounting the liquid crystal panel mounted as shown in FIG. 3 will be described. First, conductive particles or conductive resin is mixed into an adhesive to form an adhesive 15 such as an anisotropic conductive adhesive or an anisotropic conductive film, and each lead on the liquid crystal panel 11 is applied by a method such as coating, printing, or placing. An adhesive film such as an anisotropic conductive adhesive or an anisotropic conductive film is formed on a part of the circuit pattern 14 on the terminal 12 or the flexible circuit board 13. Next, the circuit pattern 14 on the flexible circuit board 13 is connected to each lead-out terminal 1 on the liquid crystal panel 11.
2 is opposed to and abuts. In this state, the liquid crystal panel 11 and the flexible circuit board 13 are bonded together under appropriate conditions.
As a result, the flexible circuit board 13 becomes the liquid crystal panel 11
The adhesive part is hermetically sealed with an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film. At this time, the circuit pattern 14 on the flexible circuit board 13
And each lead-out terminal 12 on the liquid crystal panel 11 are connected by conductive particles or conductive resin in an adhesive 15 such as an anisotropic conductive adhesive or an anisotropic conductive film interposed therebetween.

[0005]

The liquid crystal panel mounting structure as in the above-mentioned prior art is characterized in that the flexible circuit board can be easily connected to the liquid crystal panel and conductive without using solder. There is a problem in that it becomes impossible to obtain a large adhesive strength between the flexible circuit board and the liquid crystal panel as the technology becomes lighter, thinner, shorter and smaller from a technical point of view.

Therefore, the present invention has been made to solve the above-mentioned deficiencies of the prior art. The flexible circuit board and the liquid crystal panel are bonded to each other by using an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film. The purpose is to improve the adhesive strength by changing the mounting structure for connection.

[0007]

In order to solve the above-mentioned problems, the present invention provides a liquid crystal panel in which a liquid crystal layer is held by using a substrate such as glass or resin, and a liquid crystal is provided on at least one side of the substrate such as glass or resin. A large number of electrode lead-out terminals for driving the panel are arranged, and a flexible circuit board having a circuit pattern for inputting a drive signal from the outside of the liquid crystal panel to the lead-out terminals is provided, and the lead-out terminals and the flexible circuit board are provided. In a connection structure in which a part of the circuit pattern is connected using an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film, the flexible circuit board and the liquid crystal panel have a connection width of 0.2 to 2. 5
In the case of a connection structure of mm, the adhesive such as the anisotropic conductive adhesive or the anisotropic conductive film is arranged to be larger than the connection width and 0.1 to 1.5 mm longer than the side surface of the panel to be connected. The flexible circuit board and the liquid crystal panel are aligned and then connected.

[0008]

With the liquid crystal panel mounting structure of the present invention constructed as described above, an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film between the flexible circuit board and the lead-out terminal on the liquid crystal panel is provided. Become conductive by being glued for connection. At this time, an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film arranged longer than the connection width flows due to the heat transferred from the circuit pattern, and the liquid crystal panel at the connection between the flexible circuit board and the liquid crystal panel. It accumulates on the side of and hardens. Therefore, the adhesive strength between the flexible circuit board and the liquid crystal panel is improved.

[0009]

EXAMPLES The present invention will be described in detail below based on examples.

1A and 1B are views showing a mounting process of the liquid crystal panel of the present invention. In FIG. 1A, 1 is a liquid crystal panel, 2 is a lead-out terminal of an electrode for driving the liquid crystal panel 1, 3 is a substrate made of an insulating material such as a flexible circuit board, 4 is a circuit pattern on the flexible circuit board 3, and 5a. Is an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film for connecting the lead-out terminal 2 on the liquid crystal panel 1 and a part of the circuit pattern 4 on the flexible circuit board 3, and 6 is for heating and pressing. Is a tool. This Figure 1 (a)
The liquid crystal panel 1 and the flexible circuit board 3 of the tool 6
FIG. 1 (b) shows a state after heating, pressurizing, and adhering under the appropriate conditions. 5b is an adhesive such as an anisotropic conductive adhesive or an anisotropic conductive film after adhesion.

By adopting such a mounting structure, in the present invention, the liquid crystal panel 1 and the flexible circuit board 3 shown in FIG. 1A are provided with an adhesive 5 such as an anisotropic conductive adhesive or an anisotropic conductive film. When used and heated and pressed under the conditions of the tool 6 of about 180 ° C. and 45 kg / cm ² , the adhesive 5a such as an anisotropic conductive adhesive or an anisotropic conductive film will become anisotropic conductive adhesive of FIG. 1 (b). Adhesives such as adhesives and anisotropic conductive films 5b
As described above, the heat of the tool 6 transferred from the circuit pattern 4 softens and flows, and it accumulates on the side surface of the liquid crystal panel at the connecting portion between the flexible circuit board and the liquid crystal panel and hardens. Therefore, as compared with the conventional mounting structure, the area of the connecting portion between the lead-out terminal 2 and the circuit pattern 4 is not changed, and the mounting structure of the present invention is used to bond an anisotropic conductive adhesive or an anisotropic conductive film. Since the adhesive area between the adhesive 5b and the liquid crystal panel 1 and the flexible circuit board 3 is increased by the amount of the pool of the adhesive 5b such as the anisotropic conductive adhesive or the anisotropic conductive film, the flexible circuit board 3 is attached to the liquid crystal panel. No. 1 can be reliably bonded, and the bonding strength can be improved.

The inventor of the present invention uses the adhesive 5 such as an anisotropic conductive adhesive or an anisotropic conductive film to mount the flexible circuit board 3 from the side of the liquid crystal panel 1 having the mounting structure of the present invention. After adhering with a width of up to 2.5 mm, the flexible circuit board 3 was peeled by 90 degrees with respect to the liquid crystal panel 1, a peeling test was conducted, and a number of experiments and studies were conducted by measuring the strength at that time. As a result, as shown in FIG.
An adhesive 5 such as an anisotropic conductive adhesive or an anisotropic conductive film to be used is larger than the connection width between the flexible circuit board 3 and the liquid crystal panel 1 and is 0.1 to 0.1 mm larger than the side surface of the liquid crystal panel 1 to be connected. If it is arranged longer by 1.5 mm, it is 200 to 400 g / cm ² when a peeling test is performed 90 degrees upward using a liquid crystal panel having a conventional mounting structure.
It was clarified that it was possible to improve what was about 400 to 1000 g / cm ² .

The embodiment described here is merely one embodiment.

[0014]

According to the present invention, in a liquid crystal panel that holds a liquid crystal layer using a substrate such as glass or resin, a lead terminal of an electrode for driving the liquid crystal panel is provided on at least one side of the substrate such as glass or resin. It has a flexible circuit board that is arranged in a large number and has a circuit pattern that inputs a drive signal from the outside of the liquid crystal panel to the lead-out terminal. The lead-out terminal and part of the circuit pattern of the flexible circuit board are anisotropically conductively bonded. In a connection structure for connecting using an adhesive or an adhesive such as an anisotropic conductive film, when the connection structure has a connection width of 0.2 to 2.5 mm, an anisotropic conductive adhesive or an anisotropic conductive film The adhesive is larger than the connection width, and 0.1 to 1.
Adhesives such as anisotropic conductive adhesives and anisotropic conductive films, which are arranged longer than the connection width, have transmitted the circuit pattern due to the liquid crystal panel mounting structure characterized by being arranged 5 mm longer. It flows by the heat of the tool and accumulates and hardens on the side surface of the liquid crystal panel at the connecting portion between the flexible circuit board and the liquid crystal panel. The pool of adhesive such as this anisotropic conductive adhesive or anisotropic conductive film can disperse the stress applied to the connection part to other parts, and the anisotropy that covers the conductive part more than the conventional mounting structure. Since the amount of adhesive such as conductive adhesive and anisotropic conductive film increases,
It can be protected from pollutants such as moisture and organic substances in the atmosphere. In this way, since the adhesive strength between the flexible circuit board and the liquid crystal panel is improved, long-term connection reliability can be maintained, and the mounting structure of the present invention has a connection width narrower than that of the conventional mounting structure and is equivalent to that of the conventional mounting structure. Or, an adhesive strength higher than that can be obtained, which has the effect of reducing the mounting area.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a mounting process of a liquid crystal panel of the present invention.

FIG. 2 is a diagram showing the relationship between the adhesive width and the peel strength of 90 ° upward.

FIG. 3 is a sectional view showing a mounting structure of a conventional liquid crystal panel.

[Explanation of symbols]

1,11 Liquid crystal panel 2,12 Derivation terminal 3,13 Flexible circuit board 4,14 Circuit pattern 5,15 Adhesive agent such as anisotropic conductive adhesive or anisotropic conductive film 6,16 Heating and pressing tool 7,17 Liquid crystal layer 8,18 Polarizing plate

Claims (1)

[Claims] 1. A liquid crystal panel for holding a liquid crystal layer using a substrate such as glass or resin, wherein a large number of lead-out terminals of electrodes for driving the liquid crystal panel are arranged on at least one side of the substrate such as glass or resin. And a flexible circuit board having a circuit pattern for inputting a drive signal from the outside of the liquid crystal panel to the lead-out terminal, wherein a part of the circuit pattern of the lead-out terminal and the flexible circuit board is anisotropically conductive adhesive. In a connection structure in which an adhesive such as an anisotropic conductive film is used for connection, the connection width between the flexible circuit board and the liquid crystal panel is 0.2 to 2.5.
In the case of the connection structure of mm, the adhesive such as the anisotropic conductive adhesive or the anisotropic conductive film is larger than the connection width and 0.1 to 1.5 mm from the side surface of the liquid crystal panel to be connected.
A mounting structure of a liquid crystal panel, which is arranged for a long time, and the flexible circuit board and the liquid crystal panel are aligned and then connected.