JPH04324823A - Manufacture of liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide a specified gap in a short time by compressively bonding a pair of base boards with the pressure changed over at least in two steps. CONSTITUTION:A glass base board 1, on which a picture element electrode 3 and a thin film transistor 2 for driving liquid crystal are provided in the form of matrix, and another glass base board 4 on which a color filter layer 5 and a common electrode 6 are provided are affixed together through a sealing member 8. This sealing member 8 is produced from an instantaneous hardening resin by the screen printing method in such a way that a gap member 7 is included. After alignment of the two base boards affixed, they are set between a glass base board 9 admitting transmission of ultraviolet rays and a jig consisting of air cylinder 10, and a pressure of 10kg/cm<2> is applied, followed by decompression to 1.5kg/cm<2> for relieving the deformation. Then ultraviolet rays are transmitted through this base board 9 so as to irradiate the affixed two base boards, and thereby the sealing member 8 is hardened.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device, and more particularly to a method of manufacturing a liquid crystal display device suitable for obtaining a uniform gap.

0002

2. Description of the Related Art A conventional method for manufacturing a liquid crystal display device involves bonding a pair of substrates together via a sealing member and a gap control material, and then sandwiching the substrates between a pair of jigs that have good parallelism and flatness. The same pressure was applied until the seal member was cured to obtain a predetermined cell gap.

0003

However, in the prior art described above, when the pressure is increased to obtain a predetermined cell gap in a short time, especially when the gap control material is formed only outside the display area, If the cell gap becomes low and the pressure is set low, there is a problem that it takes time to obtain a predetermined gap, especially when an instant curing resin is used for the sealing member.

The present invention is intended to solve these problems, and its object is to obtain a predetermined cell gap with high precision in a short time.

[0005]

[Means for Solving the Problems] A method for manufacturing a liquid crystal display device of the present invention is a liquid crystal display device in which a pair of substrates are bonded together via a peripheral sealing member and a gap control material, and a liquid crystal is sandwiched between the substrates. The manufacturing method is characterized in that after a pair of substrates are bonded together via a peripheral sealing member and a gap control material, the pressure is switched in at least two or more stages to obtain a predetermined cell gap.

[0006]

[Embodiments] Examples of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the manufacturing process of the present invention first involves manufacturing a thin film transistor 2 and a pixel electrode 3 for driving a liquid crystal.
A glass substrate 1 having a matrix formed thereon and a glass substrate 4 having a color filter layer 5 and a common electrode 6 formed thereon are bonded together via a sealing member 8 containing a gap control material 7 formed by a screen printing method. (Figure 1 (
a)) In this example, glass fiber was used for the gap control material 7, and ultraviolet curing resin was used for the seal member 8, but the gap control material 7 and the seal member 8 are not limited to these materials. Any material may be used as long as it has a uniform thickness, can bond a pair of substrates together, and does not react with the liquid crystal. For example, the gap control material 7 includes glass balls, resin balls, and the like. Further, the sealing member 8 includes a thermosetting resin such as epoxy, a visible curing resin, and the like. Furthermore, a resin spacer such as PET (polyethylene terephthalate) or nylon may be used as both the gap control material 7 and the seal member 8.

Next, after aligning the bonded substrates, the substrates are set between a jig consisting of a glass substrate 9 that transmits ultraviolet rays and an air cylinder 10, and a predetermined cell gap is first established. To achieve this in a short time, apply a pressure of 10 kg per square centimeter and hold in this state for 1 minute. (Fig. 1(b)) At this time, as shown in Fig. 2, the specified cell gap cannot be obtained by applying a pressure of 1 kg or less, and the time required to obtain the specified cell gap by applying a pressure of 1 to 10 kg is proportional to the pressure. When applying a pressure of 10 kg or more, the pressurizing time is the same as when applying a pressure of 10 kg, but only the amount of deformation of the substrate increases.

Next, in order to eliminate deformation of the substrate, the pressure was reduced to 1.5 kg per square centimeter, and in this state 3
After 0 seconds have elapsed, the pair of bonded substrates is irradiated with ultraviolet rays through the glass substrate 9 to harden the sealing member 8. (FIG. 1(c)) When using a thermosetting resin such as epoxy for the sealing member 8, approximately 1 of the complete curing time of the resin is used.
The object of the invention is achieved by reducing the pressure in a time of /4.

[0009] Furthermore, in the case where the gap control material 7 such as a resin ball is formed also in the display area, the object of the present invention can be achieved by setting the pressure after decompression to 2.5 kg per square centimeter.

Furthermore, in this example, a jig using an air cylinder was used as a crimping jig, and the pressure was controlled by an electro-pneumatic regulator to obtain a predetermined cell gap. A jig for crimping the substrate may be used, and the pressure may be controlled by an electropneumatic regulator. In addition, when using a jig that clamps the bonded substrate between parallel jigs and places a weight on it, the pressure may be changed by reducing the weight halfway.

Finally, after the liquid crystal layer 11 is sealed in vacuum, the filling port is sealed to obtain a liquid crystal display device. (FIG. 1(d)) As described above, a predetermined cell gap was obtained in a short time by switching the pressure in at least two or more stages and pressing the pair of substrates together.

0012

As described above, according to the present invention, a predetermined cell gap can be obtained in a short period of time by switching the pressure in at least two or more stages to press-bond a pair of substrates. In particular, in a cell in which no gap control material is formed in the display area as in this example, the central part of the cell does not become thinner at all, and the liquid crystal display device manufactured by this method has very good display quality. Ta.

Furthermore, when an ultraviolet curable resin is used as in this embodiment, the manufacturing time can be significantly shortened and the yield can be improved, which has the effect that liquid crystal display devices can be manufactured in large quantities at low cost. .

[Brief explanation of drawings]

FIG. 1 is a diagram showing a book manufacturing process.

FIG. 2 is a diagram showing pressure, processing time, and amount of deformation of a substrate.

[Explanation of symbols]

1 Glass substrate 2 Thin film transistor 3 Pixel electrode 4 Glass substrate 5 Color filter layer 6 Common electrode 7 Gap control material 8 Seal member 9 Glass substrate 10 Air cylinder 11 Liquid crystal layer

Claims (3)

[Claims] 1. A method for manufacturing a liquid crystal display device, in which a pair of substrates are bonded together via a peripheral sealing member and a gap control material, and a liquid crystal is sandwiched in the gap between the pair of substrates. 1. A method of manufacturing a liquid crystal display device, which comprises bonding the liquid crystal display device together via a control material, and then changing the pressure in at least two or more stages to obtain a predetermined cell gap. 2. The method of manufacturing a liquid crystal display device according to claim 1, wherein the sealing member is an instant-curing resin. 3. The method of manufacturing a liquid crystal display device according to claim 1, wherein the gap control material is formed only outside the display area.