JPH07281141A - Liquid crystal display manufacturing method - Google Patents

Abstract

(57) [Summary] [Purpose] To minimize the occurrence of liquid crystal display panels with defective gaps even if foreign matter enters between the substrates. [Structure] A sealing material is formed in a predetermined pattern between a pair of glass substrates (step S200), and both glass substrates are bonded together while aligning them (step S201), and then only one glass substrate is cut ( (Step S202) It is possible to prevent a gap defect caused by a foreign substance entering between the liquid crystal display panels from spreading to the surroundings. Then, while pressing the substrate from above and below to adjust the gap, the sealing material is heated to cure the sealing material, and the other glass substrate is cut to efficiently mass-produce the liquid crystal display panel having no gap defect. .

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 for mass-producing liquid crystal display panels by forming a plurality of liquid crystal display panels on a pair of substrates and cutting them.

[0002]

2. Description of the Related Art A liquid crystal display device is known which displays an image by controlling the alignment of liquid crystal molecules by applying a constant electric field to a liquid crystal composition to change the optical characteristics of the liquid crystal.

FIG. 4 is a flowchart showing a part of the manufacturing process of a conventional liquid crystal display device.

When manufacturing a conventional liquid crystal display device, first, a transparent electrode and an alignment film are laminated on a facing surface of a pair of substrates using a glass plate, a resin plate or the like in a pattern that can be taken by a plurality of liquid crystal display devices. It is formed. The transparent electrode controls the orientation of liquid crystal molecules by selectively applying a driving voltage to a liquid crystal layer in a predetermined area. For example, indium tin oxide (ITO) is used as the transparent electrode.
Etc. are used, and the alignment film is for aligning the alignment of liquid crystal molecules.

Next, as shown in FIG. 5, a sealing material 5 such as an epoxy resin is formed in a predetermined plurality of frame-shaped patterns on one of the opposing surfaces of the pair of substrates 2 and 3 by a printing technique (step). S100). Here, when a spacer or the like is used for adjusting the gap between the substrates, the spacer having a predetermined particle size is uniformly dispersed in the region inside the sealing material.

Next, the substrates are attached to each other while aligning the two substrates via the above-mentioned sealing material (step S).
101).

Next, the above two substrates are pressed from above and below, and a heat treatment is performed to cure the sealing material, and the substrate positions are fixed at a substrate interval (hereinafter referred to as a gap) determined by the particle size of the spacers. A liquid crystal cell is formed (step S102).

After the sealing material is hardened, the extra substrate between the liquid crystal display panels has a scribe line that scratches the surface of the substrate along the cutting position. The substrate is cut and separated into individual liquid crystal display panels (step S103).

[0009]

However, in such a conventional method of manufacturing a liquid crystal display device, the gap between the two substrates bonded in step S101 shown in FIG. 4 is adjusted in step S102. Since the sealing material is hardened, there is a problem that a gap defect occurs when foreign matter enters between the substrates. This problem will be specifically described with reference to FIG.

FIG. 5 is a plan view during the manufacturing process of the liquid crystal display panel 1 for explaining the conventional problem.

Since the liquid crystal display panel 1 shown in FIG. 5 forms a plurality of liquid crystal display panels by using the pair of substrates 2 and 3, the sealing material 5 except the liquid crystal injection port 4 is formed at each liquid crystal display panel forming position. Is patterned by a printing method as shown in the figure, and two substrates are bonded together via the sealing material 5 to form a cell 6 for sealing the liquid crystal.

Here, if a foreign material 7 having a diameter larger than the substrate gap enters between the two substrates 2 and 3 during the manufacturing process, the substrates 2 and 3 near the foreign material 7 rise and the defective gap region is formed. 8 is formed. The liquid crystal display panel in the defective gap region 8 is cut into each liquid crystal display panel after the sealing material 5 is heated and cured in the defective gap state. Defective panels are produced and product yield is reduced.

The present invention has been made in view of the above problems, and provides a method of manufacturing a liquid crystal display device capable of minimizing the occurrence of a liquid crystal display panel having a gap defect even if a foreign matter enters between substrates. The purpose is to provide.

[0014]

A method of manufacturing a liquid crystal display device according to the present invention is a method of manufacturing a liquid crystal display device in which a plurality of liquid crystal display panels are formed on a pair of substrates and cut into individual liquid crystal display panels. Substrate bonding step of bonding the substrates via a sealing material, one substrate cutting step of cutting one substrate of the pair of substrates for each liquid crystal display panel unit, and the pair of one substrate being cut. And a sealing material curing step of curing the sealing material while pressurizing the substrates so as to face each other with a predetermined gap, and cutting the other substrate of the pair of substrates in each liquid crystal display panel unit. The other substrate cutting step of separating the liquid crystal display panel,
By having, the above object can be achieved.

[0015]

According to the first aspect of the present invention, the sealing material is applied between the pair of substrates, the substrates are adhered to each other, and only one of the two substrates is cut along a predetermined line, and then the space between the substrates is cut. While adjusting the gap, the sealing material is cured to fix both substrates at a predetermined interval, and then the other substrate is cut to separate each liquid crystal display panel.

Therefore, even if foreign matter has entered between the substrates when they are bonded together, the foreign matter can be removed by cutting only one of the substrates into individual liquid crystal display panel regions before curing the sealing material. When entering the unnecessary area between the liquid crystal display panels, the gap variation due to the foreign matter is prevented from spreading to the surrounding liquid crystal display panel, and when entering the liquid crystal display panel area, the gap variation exists the foreign matter. Limited to the liquid crystal display panel. After that, the sealing material is hardened while adjusting the gap, and finally the other substrate is similarly cut for each liquid crystal display panel and separated into individual liquid crystal display panels. The display panel can be manufactured efficiently.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 are views for explaining a method of manufacturing a liquid crystal display device according to the present invention.

FIG. 1 is a flow chart showing the manufacturing process of the liquid crystal display device of the present invention, FIG. 2 is a plan view of the liquid crystal display panel 11 according to this embodiment during the manufacturing process, and FIG.
FIG. 4 is a cross-sectional view taken along the line AA of FIG. 2 for explaining the manufacturing process of the liquid crystal display panel 11 according to this example.

A feature of the method of manufacturing a liquid crystal display device of the present invention is that a plurality of liquid crystal display panels are formed in a pair of glass substrates, and the liquid crystal display panels are cut / separated into individual panels to form a plurality of liquid crystal display panels at once. In the case of manufacturing, as shown in FIG. 1, a sealing material is formed in a predetermined pattern between a pair of glass substrates (step S200), and both glass substrates are bonded together while being aligned (step S201). First, only one side of the glass substrate is cut (step S20
2) To prevent the gap defect from spreading to the surroundings due to the foreign matter entering between the liquid crystal display panels. Then, the sealing material is heated to cure the sealing material while pressing the substrate from above and below to adjust the gap. Finally, by cutting the other glass substrate, a plurality of liquid crystal display panels with properly adjusted gaps between the substrates can be efficiently manufactured.

The method of manufacturing the above-described liquid crystal display device of the present invention will be described in detail with reference to FIGS.

In the present embodiment, for example, a segment display type liquid crystal display device (LCD) or a simple matrix display type liquid crystal display device (LCD) is manufactured by an automated manufacturing line, which will be described below in the order of steps. .

First, as shown in FIG. 3A, a glass or plastic material is used as the substrate material.
For example, here, a low-alkali glass plate of boron silicate or the like is used as the glass substrate 12. Then, after the initial cleaning of the glass substrate 12 to remove foreign substances on the surface, silica or the like is used as the undercoat film for preventing the influence of the alkaline component of the glass on the glass substrate 1.
2. Coating on the surface (not shown).

Then, an indium tin oxide (ITO) film is formed on the undercoat film, and a transparent electrode 31 patterned into a desired pattern shape is formed by a photolithography technique. Furthermore, an alignment film 32 made of a polyimide resin or the like that has been subjected to a rubbing treatment for aligning the alignment of liquid crystal molecules is laminated thereon.

Then, a sealing material 33 such as epoxy resin is applied to the peripheral edge of each liquid crystal panel by a printing technique.
As shown in FIG. 2, it is formed in a frame-shaped pattern excluding the liquid crystal injection port 14 (step S200).

Here, as shown in FIG. 3 (a), during the manufacturing process of the liquid crystal display panel, in this example, a foreign substance 17 having a diameter larger than the substrate gap between the substrates in the unnecessary regions between the individual liquid crystal display panels. May invade.

Next, in this embodiment, as shown in FIG. 3B, the other glass substrate 13 on which the transparent electrode 35 and the alignment film 36 are laminated is attached via the spacer 34 and the sealing material 33. To match. In the present embodiment, the spacers 34 for gap adjustment have a uniform particle size (several μm to several tens of μm).
m) plastic beads are used. After the spacers 34 are dispersed in the display area of the cells 6, the spacers 34 are attached while being aligned with the alignment marks of the upper and lower substrates 12 and 13.

As shown in FIG. 3 (b), when the glass substrates are bonded to each other with the foreign substance 17 penetrating between the glass substrates 12 and 13, the gap between the glass substrates is widened in the vicinity of the foreign substance 17 and the gap is increased. Defects occur.

Therefore, in the present embodiment, as shown in FIG. 2, the scribe line 19 is formed only on one glass substrate 13 and cut into substrates for each individual liquid crystal display panel. The cross section after cutting one of the glass substrates is shown in FIG.
(C) is a glass substrate 12, 13 due to the foreign matter 17.
The stress that was applied to the part is released, and only the gap in the section where the foreign matter is present becomes larger than the surrounding. The substrate unnecessary portion 13a between the liquid crystal display panels is still attached to the other substrate by an adhesive (not shown).

Next, in the state of FIG. 3C, the glass substrate 1
For Nos. 2 and 13, pressure is applied from the vertical direction to adjust the gap so that the gap has the same size as the particle diameter of the spacer 34, and heat treatment is performed at a predetermined temperature to cure the sealing material 33. As described above, in the liquid crystal display panel of the present embodiment, the gap adjustment is performed after cutting one of the glass substrates and then the sealing material is cured, so that even if the foreign matter 17 enters between the glass substrates 12 and 13. ,
It is possible to limit the spread of gap defects to a minimum area.

Then, as shown in FIG. 3D, a scribe line is formed along the cutting line of the other uncut glass substrate (see FIG. 2), and the glass substrate 12 is cut into individual The liquid crystal display panels 20, 21 and 22 are separated.

As described above, according to the method of manufacturing the liquid crystal display device of this embodiment, after the pair of glass substrates are bonded together via the sealing material formed in a predetermined pattern, the glass substrates are pressed in the vertical direction to form the gap. Before and after the step of heating and curing the sealing material while adjusting, the glass substrate was cut along the cutting line that separates each liquid crystal display panel, so that the glass substrate was cut between the glass substrates during the manufacturing process. It is possible to prevent the gap defect from being propagated to each liquid crystal display panel due to the invaded foreign matter. Therefore, it is possible to efficiently manufacture a liquid crystal display panel with good display quality in which the gap between the substrates is always controlled to be an appropriate gap.

[0033]

According to the method of manufacturing a liquid crystal display device of the present invention, a sealing material is applied between the substrates and the substrates are bonded together.
After cutting only one of the two substrates, the sealing material is cured while adjusting the gap between the substrates to fix both substrates at a predetermined interval, and the other substrate is cut to separate each liquid crystal display panel. Therefore, even if foreign matter enters between the substrates, the gap defect due to the foreign matter does not spread to the surrounding liquid crystal display panel,
It is possible to efficiently mass-produce a plurality of liquid crystal display panels with properly adjusted gaps.

[Brief description of drawings]

FIG. 1 is a flowchart showing manufacturing steps of a liquid crystal display device of the present invention.

FIG. 2 is a plan view of the liquid crystal display panel according to the present embodiment during a manufacturing process.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 for explaining the manufacturing process of the liquid crystal display panel according to this embodiment.

FIG. 4 is a flowchart showing a part of manufacturing process of a conventional liquid crystal display device.

FIG. 5 is a plan view during a manufacturing process of a liquid crystal display panel, which illustrates a conventional problem.

[Explanation of symbols]

 11 Liquid Crystal Display Panel 12, 13 Glass Substrate 14 Liquid Crystal Inlet 15 Sealing Material 16 Cell 17 Foreign Material 18 Gap Bad Area 19 Scribing Line 20, 21, 22 Liquid Crystal Display Panel 31 Transparent Electrode 32 Alignment Film 33 Sealing Material 34 Spacer 35 Transparent Electrode 36 Alignment film

Claims (1)

[Claims] 1. A method of manufacturing a liquid crystal display device, wherein a plurality of liquid crystal display panels are formed on a pair of substrates and cut into individual liquid crystal display panels, the substrate bonding step of bonding the pair of substrates through a sealing material. A substrate cutting step of cutting one of the pair of substrates for each liquid crystal display panel unit, and pressing so that the pair of substrates cut from one of the substrates face each other with a predetermined gap. And a sealing material curing step of curing the sealing material, and a other substrate cutting step of cutting the other substrate of the pair of substrates in each liquid crystal display panel unit to separate each liquid crystal display panel. A method for manufacturing a liquid crystal display device, comprising: