JP3389461B2 - Manufacturing method of liquid crystal display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly to a method for forming a sealing material.

[0002]

2. Description of the Related Art In a liquid crystal display device, an electrode pattern made of transparent electrodes such as ITO is formed on a pair of electrode substrates made of glass or plastic, and an alignment film made of polyimide is formed, and then epoxy resin or the like is used. It is manufactured by forming a seal pattern with a seal material composed of, bonding a pair of electrode substrates, dividing the electrode substrate, and injecting a liquid crystal material.

As shown in FIGS. 5 and 6, in the conventional liquid crystal display device, the seal pattern 51 is formed inside the end portion of the electrode substrate 52 by about 0.3 to 0.5 mm. Therefore, in the case where the electrode substrate 52 is made of glass, the electrode substrate 52 may be formed at the portion A outside the seal pattern 51.
There is a problem that the cracks and cracks.

When the electrode substrate 52 is made of plastic, the electrode substrate 52 has flexibility, so
There is a problem that so-called seal peeling occurs in which the seal pattern 51 is peeled from the electrode substrate 52 when a stress is generated in the portion. When the plastic is hard and brittle, in addition to peeling off the seal, the electrode substrate 5 as well as the glass is used.
There is a problem that 2 is cracked or chipped.

The term "hard and brittle" as used in the present application means that when a plastic is folded in two like a paper is folded in two, what is cracked is hard and brittle. It should be noted that even a hard and brittle property has flexibility.

Reference numeral 53 in FIG. 5 indicates a terminal connected to the drive circuit, and reference numeral 54 in FIG. 6 indicates a liquid crystal material.

In order to solve the above-mentioned problems, it is considered that the problem can be solved by forming the seal pattern 51 on the end portion of the electrode substrate 52 as shown in FIG.

[0008]

However, the seal pattern formed to have a thickness of about 20 to 30 μm by screen printing or drawing with a dispenser has a thickness of 4 due to the pressure applied when the pair of electrode substrates are bonded together. The liquid crystal display device is configured in a state of being thinly extended to about 6 μm.

Therefore, as shown in FIG. 8 which is an enlarged view of portion B in FIG. 7, the end portion of the seal pattern 51 is not linear, and the seal pattern 51 is formed along the end portion of the electrode substrate 52. Will be difficult.

The present invention has been made in view of the conventional problems as described above, and the seal pattern can be easily formed along the end portion of the electrode substrate, and the electrode substrate may be cracked, chipped, or broken. It is an object of the present invention to provide a method for manufacturing a liquid crystal display device capable of preventing peeling of a seal.

[0011]

In order to achieve the above-mentioned object, a method of manufacturing a liquid crystal display device according to the present invention comprises a step of bonding a pair of electrode substrates with a sealing material, and then performing a cutting operation along a dividing line. In a method of manufacturing a liquid crystal display device in which an electrode substrate is divided, a plurality of liquid crystal display devices are electrically connected to the electrode substrate.
A pole pattern is formed, and a sheet matching the electrode pattern is formed.
Is a manufacturing method in which
The adjacent seal patterns are integrally formed.
Together with the side other than the side where the terminals connected to the drive circuit are formed, the sealing material is formed so as to straddle the dividing line, and the pair of electrode substrates are bonded together, and then the electrode is formed together with the sealing material. Divide the substrate into multiple liquid crystals
It is characterized in that it is divided into display devices .

[0012]

[0013]

[0014]

[0015]

Further, the portion for integrating the seal pattern is characterized in that the a terminal and sides other than the side that forms the liquid crystal injection port.

According to the method of manufacturing the liquid crystal display device of the present invention, the sealing material is formed so as to straddle the dividing line on the sides other than the side where the terminals connected to the drive circuit are formed, and the sealing substrate and the electrode substrate. By dividing the parts, it is possible to easily form the seal pattern along the end portion of the electrode substrate and prevent the electrode substrate from being cracked or chipped.

Further, when the electrode substrate is made of plastic, it becomes easy to divide the electrode substrate together with the sealing material, and peeling of the seal can be prevented.

Further, since the area where the sealing material and the electrode substrate are in close contact with each other before the division is large, the adhesive force between the sealing material and the electrode substrate is increased, and the distance between the pair of electrode substrates is increased.
The so-called cell gap uniformity can be improved.
As a general method for bonding a pair of electrode substrates, a method is used in which heating and pressurization are simultaneously performed, and then only the heating is performed to cure the sealing material. If is a plastic, the electrode substrate may warp and impair the uniformity of the cell gap in the process of only heating, but by suppressing the warpage of the electrode substrate by increasing the adhesion between the sealing material and the electrode substrate, The uniformity of the cell gap can be improved.

Further, when the electrode substrate is a hard and brittle plastic, it becomes easy to divide the electrode substrate together with the sealing material, and the electrode substrate is prevented from cracking, chipping, and peeling of the seal. be able to.

Further, since the cutting method is the dicing method using the rotary blade, the electrode board can be easily cut together with the sealing material regardless of whether the material of the electrode board is glass or plastic.

When a plurality of liquid crystal display device electrode patterns are formed on an electrode substrate and a seal pattern matching the electrode pattern is formed by a seal material, adjacent seal patterns are integrally formed to form a pair of electrode substrates. After bonding, by dividing into multiple liquid crystal display devices, it is possible to further increase the contact area between the sealing material and the electrode substrate before dividing, and the adhesive force between the sealing material and the electrode substrate. Is further increased, and the uniformity of the cell gap can be further improved.

According to this method, a part of the seal pattern is broken so that air can freely flow in and out of the liquid crystal display device, that is, the seal material and the electrode substrate before being divided without generating a so-called seal path. It is possible to increase the area in close contact with. This means that, when the adjacent seal patterns are formed separately, when the heating and the pressing at the time of bonding the pair of electrode substrates are simultaneously performed, the adjacent seal patterns are thinly extended. However, the air existing between the adjacent seal patterns may be left behind in the seal pattern at this time, and the volume of this air expands due to heating, breaking the seal pattern and breaking the seal path. This is because it can be prevented. That is, if the adjacent seal patterns are integrally formed before bonding, a large amount of air is not included in the seal pattern, so that the seal material and the electrode substrate can be in close contact without generating a seal path. It is possible to increase the area occupied.

Further, since the portion where the seal pattern is integrated is the side other than the side where the terminals and the liquid crystal injection port are formed, the connection with the drive circuit is not adversely affected and the seal path is generated. There is no.

If the seal pattern on the side where the liquid crystal injection port is formed is integrated with the adjacent seal pattern, the portion which becomes the liquid crystal display device becomes a closed space, and for the same reason as the above-mentioned seal path occurs, The volume of air in the closed space expands due to the heating in the subsequent bonding step, breaking the seal pattern to form a seal path.

[0026]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIGS. 1 is a plan view showing a liquid crystal display device according to the present invention, FIG. 2 is a sectional view showing a liquid crystal display device according to the present invention, FIG. 3 is a plan view showing a seal pattern according to the present invention, and FIG. It is explanatory drawing which shows the process.

As shown in FIGS. 1 and 2, in the liquid crystal display device manufactured by the method of manufacturing the liquid crystal display device of the present invention, the seal pattern 1 is formed along the end portion of the electrode substrate 2, and the seal pattern 1 is formed. The outer edge is straight. Further, on the side where the terminal 3 connected to the drive circuit is formed, the seal pattern 1 is formed inside by 0.3 to 0.5 mm from the end portion of the electrode substrate 2, and the end portion on the outer side of the seal pattern 1 is formed. Are not shown, but are not linear. The method of manufacturing such a liquid crystal display device will be described below.

(Embodiment 1) A transparent electrode made of ITO is formed on a pair of electrode substrates made of glass having a thickness of 0.7 mm, and the transparent electrode is patterned by a photolithography method to form electrodes of a plurality of liquid crystal display devices. Form a pattern. Then, an alignment film made of polyimide or the like is formed, and an alignment treatment by a rubbing method is performed.

Next, as shown in FIG. 3, a seal material made of, for example, an epoxy resin is applied to one electrode substrate 2 by screen printing or drawing with a dispenser to form seal patterns 1 for a plurality of liquid crystal display devices. . Spacers for controlling the cell gap of the liquid crystal display device are arranged on the other electrode substrate.

The seal pattern 1 is formed so as to extend over the dividing line 4 on three sides except the side where the terminals 3 are formed. In order to make the seal pattern 1 straddle the dividing line 4, the seal material may be made to straddle the dividing line 4 when the sealing material is applied by screen printing or drawing with a dispenser. The seal pattern 1 may be extended thinly and then straddle the dividing line 4. By doing so, it is possible to easily form the seal pattern 1 along the end portion of the electrode substrate 2 after the division, and it is possible to prevent the electrode substrate 2 from being cracked or chipped.

Further, regarding the side where the terminal 3 is formed, the seal pattern 1 does not straddle the dividing line 4 even if the seal pattern 1 is thinly extended in the subsequent bonding step. Form. This is because if the seal pattern 1 straddles the dividing line 4 on the side where the terminal 3 is formed, the terminal 3 may be damaged and broken during the division, or the seal pattern 1 may remain on the terminal 3 portion after the division. This is because there is a problem that the connection with the drive circuit cannot be performed well.

The seal pattern 1 has rows a, b, c and d from the top row of the liquid crystal display device in FIG. Since the terminals 3 are formed between the rows, the adjacent seal patterns 1 are not integrated, but the terminals 3 are provided between the rows b and c.
Is not formed, the adjacent seal patterns 1 are integrally formed. By doing this,
Since the area of close contact between the seal pattern 1 and the electrode substrate 2 can be increased without generating a seal path, the close contact force between the seal pattern 1 and the electrode substrate 2 is increased, and the uniformity of the cell gap is improved. Can be made.

The reason why the seal pass occurs will be described with reference to FIG. As shown in FIG.
When the adjacent seal patterns 1 are formed separately,
When heating and pressurizing the pair of electrode substrates at the same time are performed at the same time, the adjacent seal patterns 1 are thinly extended and integrated with each other.
As shown in (b), the air 6 existing between the adjacent seal patterns 1 at this time may be left behind in the seal pattern 1, and the volume of the air 6 expands due to heating, and the air 6 shown in FIG. ), The seal pattern 1 is broken to form the seal path 7.

That is, as shown in FIG. 3, if the adjacent seal patterns 1 are integrally formed before the bonding, a large amount of air is not contained in the seal pattern 1 and a seal path is generated. Since the area where the seal pattern 1 and the electrode substrate 2 are in close contact can be increased without increasing the size, the adhesion force between the seal pattern 1 and the electrode substrate 2 can be increased, and the uniformity of the cell gap can be improved. is there.

Further, the seal pattern 1 is defined as columns e, f, and g from the leftmost liquid crystal display device in FIG. 3, between columns e and f and between columns f and g. Since the liquid crystal injection port 5 is formed, the adjacent seal patterns 1 are not integrated. This is because if the liquid crystal injection port 5 part is integrated with the adjacent seal pattern 1, the part that becomes the liquid crystal display device becomes a closed space, and therefore, the bonding process after that is performed for the same reason as the above-mentioned seal path occurs. This is because the volume of air in the closed space expands due to the heating in the process and breaks the seal pattern 1 to form a seal path.

Next, a pair of electrode substrates 2 are bonded together, and heating and pressing are performed at the same time, and then only heating is performed to cure the seal pattern 1, and the dividing line 4 is formed by a dicing method using a rotary blade. A liquid crystal display device is obtained by dividing the electrode substrate 2 along the line, injecting a liquid crystal material from the liquid crystal injection port 5, and connecting a drive circuit to the terminal 3.

By using a dicing method using a rotating blade as a dividing method, the electrode substrate 2 and the seal pattern 1 can be simultaneously and easily divided, and the electrode substrate 2 is sealed along the end portion thereof. The pattern 1 can be formed so that its outer end portion is linear.

(Embodiment 2) As a pair of electrode substrates,
A liquid crystal display device is manufactured in the same manner as in Embodiment 1 except that a plastic film such as polyether sulfone is used.

When a plastic film is used as the electrode substrate, it becomes easy to divide the electrode substrate together with the seal pattern, and peeling of the seal can be prevented.

Further, when the electrode substrate is a plastic film, there is a problem that the electrode substrate warps in the process of only heating after simultaneously performing heating and pressurization in the bonding process and the uniformity of the cell gap is impaired. However, as described above, by increasing the adhesion between the sealing material and the electrode substrate, it is possible to suppress the warp of the electrode substrate and significantly improve the uniformity of the cell gap.

(Embodiment 3) As a pair of electrode substrates,
A liquid crystal display device is manufactured in the same manner as in Embodiment 1 except that a plastic having a hard and brittle property such as an epoxy resin or an acrylic resin is used.

The plastic having a hard and brittle property as used in the present invention is called a plastic having a hard and brittle property, which is broken when the plastic is folded in two such as folding paper into two. I have decided. The plastic film such as polyethersulfone described in Embodiment 2 does not crack even when folded in two. Note that even a plastic that is hard and brittle has flexibility.

When a plastic having a hard and brittle property is used as the electrode substrate, it becomes easy to divide the electrode substrate together with the seal pattern, and it is possible to prevent cracking and chipping of the electrode substrate and peeling of the seal.

Further, even when the electrode substrate is a hard and brittle plastic, the electrode substrate warps in the process of only heating after simultaneously performing heating and pressurization in the bonding process, and the uniformity of the cell gap is maintained. However, as described above, the warp of the electrode substrate is suppressed by increasing the adhesive force between the sealing material and the electrode substrate,
The uniformity of the cell gap can be significantly improved.

[0045]

As described above, according to the method of manufacturing a liquid crystal display device of the present invention, the sealing material is arranged so as to straddle the dividing line on the side other than the side where the terminals connected to the drive circuit are formed. By forming the seal pattern and dividing the electrode substrate together with the seal material, the seal pattern can be easily formed along the end portion of the electrode substrate, and cracking and chipping of the electrode substrate can be prevented.

Further, when the electrode substrate is made of plastic, it becomes easy to divide the electrode substrate together with the sealing material, and peeling of the seal can be prevented. Further, since the area where the sealing material and the electrode substrate are in close contact with each other before the division is large, the adhesive force between the sealing material and the electrode substrate is increased, and the uniformity of the cell gap can be improved.

Further, when the electrode substrate is a plastic having a hard and brittle property, it becomes easy to divide the electrode substrate together with the sealing material, and cracks and chips of the electrode substrate and peeling of the seal are prevented. be able to.

Further, since the cutting method is the dicing method using the rotary blade, the electrode board can be easily cut together with the sealing material regardless of whether the material of the electrode board is glass or plastic.

When a plurality of liquid crystal display device electrode patterns are formed on an electrode substrate and a seal pattern matching the electrode pattern is formed by a seal material, adjacent seal patterns are integrally formed to form a pair of electrode substrates. After bonding, by dividing into multiple liquid crystal display devices, it is possible to further increase the contact area between the sealing material and the electrode substrate before dividing, and the adhesive force between the sealing material and the electrode substrate. Is further increased, and the uniformity of the cell gap can be further improved. Further, it is possible to increase the area where the sealing material before being divided and the electrode substrate are in close contact with each other without generating a sealing path.

Further, since the portion where the seal pattern is integrated is the side other than the side where the terminals and the liquid crystal inlet are formed, the connection with the drive circuit is not adversely affected and the seal path is generated. There is no.

[Brief description of drawings]

FIG. 1 is a plan view showing a liquid crystal display device according to the present invention.

FIG. 2 is a cross-sectional view showing a liquid crystal display device according to the present invention.

FIG. 3 is a plan view showing a seal pattern according to the present invention.

4A to 4C are explanatory views showing a process in which a seal path occurs.

FIG. 5 is a plan view illustrating a seal pattern of a conventional liquid crystal display device.

FIG. 6 is a cross-sectional view illustrating a seal pattern of a conventional liquid crystal display device.

FIG. 7 is a plan view illustrating another seal pattern of the conventional liquid crystal display device.

FIG. 8 is an enlarged view of part B in FIG.

[Explanation of symbols]

1 seal pattern 2 electrode substrate 3 terminals 4 dividing lines 5 Liquid crystal inlet 6 air 7 seal pass 51 seal pattern 52 electrode substrate 53 terminals 54 Liquid crystal material

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G02F 1/1339 505 G02F 1/1333 500 G02F 1/13 101

Claims (2)

(57) [Claims] 1. A method of manufacturing a liquid crystal display device, comprising: bonding a pair of electrode substrates via a sealing material; then dividing the electrode substrates along a dividing line, wherein electrodes of a plurality of liquid crystal display devices are provided on the electrode substrate. Shape pattern
A seal pattern that matches the electrode pattern.
In the manufacturing method of forming the seal material, the adjacent seal patterns are integrally formed.
On the other hand, on the side other than the side on which the terminal connected to the drive circuit is formed, the sealing material is formed so as to straddle the dividing line, and after bonding the pair of the electrode substrates, the sealing material and the Multiple liquid crystal displays by dividing the electrode substrate
A method for manufacturing a liquid crystal display device, characterized in that the device is divided into devices. 2. A part of integrating the sealing pattern, the method of manufacturing the liquid crystal display device according to claim 1, wherein the a terminal and sides other than the side that forms the liquid crystal injection port.