JPH02239231A - Production of liquid crystal display element - Google Patents

Abstract

PURPOSE:To assure and stabilize the conduction between an electrode terminal and a connector and to improve reliability by applying solder by dipping on an Ag layer formed on the electrode terminal and further slightly polishing the solder layer to flatten the surface. CONSTITUTION:Ag paste is printed on the electrode terminal 4 prior to the assembly of a cell and is calcined, for example, for 10 minutes at 500 deg.C to form the Ag layer 5 at the time of producing an LCD 1. One side end of a lower glass substrate 3 is dipped into a solder tank after the assembly of the cell and is pulled up at a prescribed speed to form the solder layer 6 on the Ag layer 5. The solder layer obt. in such a manner is built up by surface tension and, therefor, the surface is polished by 1 to 2mum and is thereby flattened after the dipping. The contact stability of the solder layer 6 and a contact point part 11a of the connector 10 is improved in this way and the insertion of the connector 10 to the LCD 1 is facilitated. The damage of the glass substrate at the time of insertion of the connector is thus averted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a liquid crystal display element (hereinafter referred to as LCD) that is used by connecting electrode terminals to a connector. [Prior art] Electrode terminals arranged on one side edge of a glass substrate of an LCD are
It is formed by extending a transparent electrode made of ITO,
When manufacturing an LCD that is used by connecting these electrode terminals to a connector, an Ag layer or a carbon layer is usually formed on the electrode terminals before cell assembly. Then, connect the contact part of the connector inserted into one side edge of the glass substrate of the LCD to the above-mentioned Ag.
By bringing the connector into contact with the carbon layer or the carbon layer, continuity between the connector and the electrode terminal is ensured.

[The problem that the invention attempts to solve! ] however. Since the exposed surface of the Ag layer is easily oxidized or sulfided, the resistance value increases over a long period of time, and there is a risk that poor conductivity (not displayed) may occur. On the other hand, although the carbon layer is less affected by oxidation and sulfidation, it is soft and will wear off when the connector is repeatedly connected and disconnected, potentially causing poor continuity or short circuits. In addition, since carbon has a large particle size, if a carbon layer is formed before the cell assembly process in which two large substrates are bonded together and then cut, the gap accuracy between the two substrates is likely to deteriorate, especially when the gap This had the disadvantage that it was not possible to manufacture LCDs with a diameter of 8 μm or less. Therefore, an object of the present invention is to solve the problems of the prior art described above. To provide a method for manufacturing an LCD that can reliably conduct a single-pole terminal to a connector, has high reliability, and does not deteriorate gap accuracy.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides A
After gNj is formed, solder is applied onto this Ag layer by dipping, and the solder layer is further polished a little to make the surface flat.

[Function] According to the above means, since the Ag layer is covered with a solder layer, oxidation and sulfidation can be avoided, and there is no worry that the solder layer will be scraped even if the connector is repeatedly attached and detached. Since the solder layer can be formed after cell assembly, there is no need to worry about deteriorating gap accuracy.

[Example] below. Embodiments of the present invention will be described based on the drawings.

FIG. 1 is a main part explanatory view showing a state in which a connector is attached to an LCD according to an embodiment of the present invention, and the opposing surfaces of an upper glass substrate 2 and a lower glass substrate 3 of the LCD are made of transparent material made of ITO. An electrode (not shown) is patterned, and three to three electrodes are formed on the electrode terminal 4 extending from this transparent electrode.
An Ag layer 5 with a thickness of 5 μm is provided, and a solder layer 6 with a thickness of about 20 μm and a flat surface is further provided on the AgNS. On the other hand, the connector 10 is composed of a conductor 11 having a contact portion 11a and a lead portion 1lb, and a resin molded body 12 into which the conductor 11 is inserted.
A lead n13 for leading to the outside is soldered to. When the connector 1o is inserted into one side of the lower glass substrate 3, the contact portion 11a stably contacts the flat surface of the solder layer 6, so that the electrode terminal 4 and the connector are connected to each other via the Ag layer and the solder layer 6. Continuity with 10 is ensured. Now, when manufacturing the above LCD 1, before assembling the cell, Ag paste is printed on the electrode terminal 4 and baked at, for example, 500° C. for 10 minutes to form Agl 5. After cell assembly, one side of the lower glass substrate 3 is dipped into a solder bath and pulled up at a predetermined speed to form a solder layer 6 on the Ag layer 5. In other words, since there is a correlation as shown in Figure 2 between the pulling speed of the cell and the thickness of the solder layer during dipping, by setting the pulling speed to 40 m/sec, a solder layer with a thickness of about 20 μm can be drawn. can get. In addition, the solder layer obtained in this way is raised due to surface tension, so after dedicating, the surface is
Planarize by μ-tone polishing. This improves the contact stability between the solder layer 6 and the contact portion 11a of the connector 10, and also facilitates insertion of the connector 10 into the LCD 1, making it possible to avoid damage to the glass substrate when the connector is inserted.

As described above, in the above embodiment, the solder layer 6 is provided on the Ag layer 5, and the surface of the solder layer 6 is flattened, so that oxidation and sulfurization of the Ag layer 5 can be avoided, and the soldering period can be reduced. 6 and the contact portion 11a of the connector 10 can be brought into stable contact with each other.
The conduction with 0 is reliable and stable. Also,
Since the solder 16 can be formed after cell assembly, the solder layer 6
This does not deteriorate the gap accuracy of the LCD 1, and therefore, even if the LCD has a small gap of 8 μin or less, it will not cause any trouble in manufacturing. Moreover, the solder layer 6 can be easily formed by dipping, and there is no fear of it being scraped even if the connector 10 is repeatedly attached and detached, so the yield is good.
Therefore, total cost can be reduced.

According to experiments conducted by the present inventors, if the film thickness of the solder layer 6 is set to 30 μm or more, the lower glass substrate 3 is likely to be chipped or cracked when the connector 10 is inserted, and the solder N
If the thickness of the solder layer 6 is set to 10 μm or less, the contact stability with the contact portion 11a of the connector 10 will deteriorate.
The film thickness is lo~30μnga (preferably 15~30μnga).
25μum) is good.

[Effects of the Invention] As explained above, the present invention provides A. After forming the layer, solder is applied on this AgM by dipping, and the solder layer is further polished a little to make the surface flat, so 1! In addition to ensuring reliable and stable conduction between the electrode terminals and the connector, improving reliability, the solder layer can be formed after cell assembly, making it possible to manufacture LCDs with small gaps, further improving yields and reducing total costs. It has various effects such as reducing

[Brief explanation of drawings]

FIG. 1 is an explanatory view of the main parts showing a state in which a connector is attached to an LCD according to an embodiment of the present invention, and FIG. 2 is a characteristic showing the correlation between the cell pulling speed and the solder layer thickness during the dipping process. This is a diagram. 1...LCD, 4...
... Electrode terminal, 5 ... Ag layer, 6 ...
...Solder 1, 10...Connector, 11a...
...Contact part. Figure 2 (pm) ▲ Cell pull-up F1 degree

Claims (1)

[Claims] In a liquid crystal display element that is used by connecting an electrode terminal extending from a transparent electrode to a connector, an A is placed on the electrode terminal.
A method for manufacturing a liquid crystal display element, which comprises forming a G layer, applying solder on the Ag layer by dipping, and polishing the solder layer a little to make the surface flat.