JPS6134647B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing a liquid crystal display device.

Generally, a liquid crystal display device, as shown in FIG.
Substrates 1a and 1b at least one of which is made of a transparent material
A liquid crystal is sealed in an envelope 2 configured by arranging the substrates 1 and 1 to face each other with a spacer 1c interposed therebetween.
changing the optical properties of the liquid crystal between the electrodes (not shown) respectively deposited on the opposing surfaces of a and lb;
This change is configured to be recognized through the transparent electrode on the substrate side made of a transparent material among the electrodes.

In this case, the change in the optical properties of the liquid crystal is
It greatly depends on the spacing between the electrodes formed by depositing on the electrodes a and 1b, and if the spacing is uneven, the time response characteristics of optical changes will be uneven, and if the spacing is narrow, the lifespan of the liquid crystal will be shortened. deteriorates. Therefore, it is required that the spacing between each electrode be uniform and maintained at a constant value (for example, 10 μm±0.1 μm).

In a conventional liquid crystal display device, each substrate 1a,
A method is adopted in which the distance between each electrode is regulated by a spacer 1c interposed between the spacers 1b and 1b.
As c, abrasive grains, fine particles, flat sheets, fibrous glass fibers, or the sealing material itself for each of the substrates 1a and 1b has been used. However, in a liquid crystal display device having such a configuration, each substrate 1
Even if the distance around a and 1b can be regulated, each board 1
The distance between the centers of a and 1b is, for example,
The thickness of the substrates 1a and 1b may exceed the thickness of the spacer 1c due to warping of the substrates 1a and 1b, and unless a spacer is also fixed to this portion, it is not possible to make the substrates 1a and 1b face each other with uniform spacing. When fixing the spacer to the center of each substrate 1a, 1b, after positioning the spacer at an appropriate location using the fixing material, a load is applied from the side of each substrate 1a, 1b.
This requires a complicated work of fixing the substrates 1a and 1b at a predetermined interval, and also has drawbacks such as contamination of the display surface by the organic binder in the fixing material.

Therefore, the present invention provides a method of manufacturing a liquid crystal display device which is easy to assemble and has excellent reliability, in which the substrates are faced to each other at uniform predetermined intervals.

The present invention will be explained in detail below using examples.

FIGS. 2a, 2b and 3 are explanatory diagrams showing an embodiment of the method for manufacturing a liquid crystal display device according to the present invention. First, in Figure 2 a, 100mm x 100mm x 1
There are glass substrates 1a and 1b of mm(t), and a transparent conductive layer 3 is provided on the surface of the substrate 1a facing the substrate b.
are formed, and spacers 4 of 0.1 mmφ×10 μt made of, for example, aluminum foil or copper foil are scattered in contact with the transparent conductive layer 3. As shown in FIG. 3, the transparent conductive layer 3 has seven segment electrodes 3a arranged in a "h" shape in one display area, and each segment electrode 3a is connected to the substrate 1.
It consists of a wiring layer 3b drawn out around a.
Then, the anode of a DC power source 5 (600V) is connected to the transparent conductive layer 3 connected to each spacer 4, and the cathode 6 of the power source 5 is placed on the surface of the substrate 1a on which the transparent conductive layer 3 is not formed. With this, an electric field is generated in the substrate 1a under the spacer 4, and the temperature is heated to approximately 300°C using an appropriate heating device (not shown).
Heat treatment is performed for about 1 minute. By doing this, the spacer 4 is firmly adhered to the substrate 1a, but the mechanism of this adhesion is such that, as shown in FIG. It is considered that the negative ions move and the number of negative ions increases on the spacer 4 side, and the positively charged spacer 4 is attracted to the substrate 1a side and adheres at the interface 7. Thereafter, as shown in FIG. 2b, after placing the substrates 1b and 1a facing each other so that the substrates 1b are in contact with the markings of the spacers 4, the cathode 6 of the power source 5 is placed on the outer surface of the substrate 1b, With this, an electric field is generated within the substrate 1a at the portion in contact with the spacer 4, and heat treatment is performed at about 300° C. for about 1 minute using a heating device. Even in this case, the spacer 4 and the substrate 1b are firmly adhered at the interface 8 between them, so that the substrate 1b
a and 1b are held facing each other with an interval equal to the thickness of the spacer 4 maintained therebetween.

In this way, each of the substrates 1a, which are arranged facing each other,
Since the spacers 4 can be arranged scattered in and around the center of the substrate 1b, the substrates 1a and 1b can be held facing each other while maintaining a constant and uniform interval depending on the thickness of the spacer 4 made of aluminum foil or copper foil. can. Since the spacer 4 can be adhered to each substrate 1a, 1b without using an adhesive, the complexity of the process associated with the use of an adhesive can be eliminated, and the display surface is not contaminated by the organic binder in the adhesive. Reliability can be improved by not doing so. In the above embodiment, the distance between each substrate 1a, 1b was kept uniform at 10μ±1μ or more.

In this embodiment, the spacer 4 is connected to the segment electrode 3.
a or the wiring layer 3b connected to the segment electrode 3a,
A wiring layer for a spacer may be formed independently, and the spacer may be connected to this wiring layer.

Further, although the bonding between the spacer 4 and each substrate 1a, 1b is performed in a separate process for each substrate 1a, 1b, it is also possible to interpose the spacer 4 between each substrate 1a, 1b and perform the bonding at the same time. good.

Further, the voltage applied between the spacer 4 and the back surface of the substrate to which this spacer 4 is bonded is applied to the spacer 4.
Although the side was set at a positive potential, the same effect could be obtained even if the reverse was done.

Furthermore, in this example, the applied voltage value is
The spacer was bonded to the substrate surface by heating at 600V and heating temperature at 300°C for about 1 minute.
If the temperature is less than ℃, the movement of ions in the substrate will be small.
If the electric field is no longer generated and the voltage value is higher than 2000V and the heating temperature is higher than 800℃, an excessive current will flow and the substrate will be electrolyzed and Na ions will be precipitated to the negative electrode side, functioning as a display device. The voltage value is 100V to 2000V,
The heating temperature can be set within the range of 100°C to 800°C.

Note that although aluminum foil, copper foil, or the like was used as the spacer 4, similar effects were obtained using other conductive thin plates.

As described above, according to the method of manufacturing a liquid crystal display device according to the present invention, each substrate is faced to each other at uniform predetermined intervals, and a device that is easy to assemble and has excellent reliability can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of a conventional liquid crystal display device, FIGS. FIG. 3 is a diagram explaining the principle of one step in the method for manufacturing a liquid crystal display device according to the present invention. 1a, 1b...Substrate, 1c, 4...Spacer,
2... Envelope, 3... Transparent conductive layer, 3a... Segment electrode, 3b... Wiring layer.

Claims (1)

[Claims] 1. A liquid crystal display device in which a liquid crystal is sealed in an envelope formed by arranging a pair of substrates facing each other with a spacer interposed therebetween, and electrodes are attached to the opposing surfaces of each substrate. A method for manufacturing a liquid crystal display device, characterized in that the spacer is a conductive thin plate and the spacer is fixed to each substrate by creating an electric field between the spacer and the substrate and heating it. 2 Create a DC potential difference between the spacer and the substrate.
2. The method of manufacturing a liquid crystal display device according to claim 1, wherein the spacer is fixed to the substrate by applying a voltage within a range of 100V to 2000V and heating within a range of 100°C to 800°C.