JPH11174474A - Production of liquid crystal display device and liquid crystal injection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a liquid crystal display device capable of improving the production line pitch time of a vacuum injection method and improving the equipment working rate of a liquid crystal injection device. SOLUTION: This process for production consists in producing the liquid crystal display device by injecting a liquid crystal material into the internally enclosed space of a liquid crystal cell consisting of a pair of substrates arranged to face each other and a sealant formed between a pair of the substrates exclusive of an aperture. At this time, the liquid crystal cell P is carried into a vacuum vessel 60 and thereafter the internal space of the liquid crystal cell P is pressure reduced. The aperture of the liquid crystal cell P is immersed into the liquid crystal material 65 within the vacuum vessel 60 after pressure reduction. The atm. pressure is restored in the vacuum vessel 60 and in the state of immersing the aperture into the liquid crystal material 65, a pair of the substrates are transported to the outside of the vacuum vessel 60.

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 a liquid crystal injection device using the method.

[0002]

2. Description of the Related Art In the manufacture of a liquid crystal display device, a uniform gap is formed over the entire surface between a pair of superposed substrates by spacers having a diameter of about 4 μm scattered on the surface of the substrate, and a liquid crystal material is injected into this gap. There is a liquid crystal injection step. This liquid crystal injection process is positioned as an important process in production lines to improve the yield, because it is necessary to suppress the generation of bubbles in the gap on the order of microns and to reliably fill the liquid crystal material. I have.

Next, a liquid crystal cell will be described, and then an outline of a typical liquid crystal injection method (vacuum injection method) will be described. As shown in FIGS. 13 and 14, the first transparent insulating substrate 50 and the second transparent insulating substrate 51 of the liquid crystal cell P are provided with electrodes 52 and 53 in a predetermined pattern on the surfaces in contact with the liquid crystal material, respectively. Have been. Further, a sealing material 55 is formed to seal the internal space of the gap formed by the spacer 54 along the periphery of the substrate. In order to fill the internal space with the liquid crystal material in the liquid crystal injection step, a part of the sealing material 55 is filled with an injection port 56 not provided with the sealing material.
Are formed. Further, a silica material having a predetermined diameter, which plays a role similar to that of the spacer 54, is mixed in the seal material 55.

As an injection device used in the conventional liquid crystal injection method, as shown in FIG. 15, a vertically movable loading plate 61 and a liquid crystal storage member are provided inside a vacuum container 60 (the whole structure of the vacuum container is not shown). 62 and liquid crystal cell P
A transport member 64 for transporting the cassette 63 containing the is provided. First, as shown in FIG. 16, in a state where the injection port 56 of the liquid crystal cell P is not immersed in the liquid crystal material 65 of the liquid crystal storage member 62, the inside of the vacuum container 60 is evacuated. For example, about 1P
a. Then, as shown in FIG. 17, after the tip of the liquid crystal injection port 56 is immersed in the liquid crystal material 65 and the inside of the vacuum container 60 is set to the atmospheric pressure, the internal space 6 of the liquid crystal cell P is reduced.
The liquid crystal material 65 fills the internal space 66 of the liquid crystal cell P due to the pressure difference between the pressure 6 (vacuum depressurized state) and the atmospheric pressure.

[0005] Such a vacuum injection method has excellent injection reliability and can inject an expensive liquid crystal material without waste. There is a manufacturing apparatus in which a series of steps from deaeration, defoaming, and sealing of an injection port are performed in an in-line manner using this vacuum injection method (see Japanese Patent Application Laid-Open No. 5-307160).

[0006]

However, the vacuum injection method generally has the following problems.

(1) Since the gap between the substrates is extremely narrow (about 4 μm), the inflow viscous resistance of the liquid crystal material increases,
It takes a long time to completely fill the inside of the liquid crystal cell with the liquid crystal material. For example, in the case of a 12-inch liquid crystal cell, a filling time of about 4.5 hours is required. This leads to a reduction in production tact.

(2) Until the filling of the liquid crystal material is completed, since one cassette occupies the vacuum container, the equipment operation rate of the vacuum container decreases.

[0009] As the screen size of liquid crystal cells increases, these have become serious problems to be solved in order to improve productivity.

In view of the circumstances described above, the present invention provides a method of manufacturing a liquid crystal display device and a liquid crystal injection device capable of improving the production tact time of the vacuum injection method and improving the operation rate of the liquid crystal injection device. The purpose is to provide.

[0011]

According to the present invention, there is provided a method of manufacturing a liquid crystal display device, comprising: a pair of substrates disposed to face each other; and a sealing material formed between the pair of substrates except for an opening. A liquid crystal display device manufacturing method for manufacturing a liquid crystal display device by injecting a liquid crystal material into the internal space of a liquid crystal cell comprising:
After the liquid crystal cell is loaded into the vacuum container, a depressurizing step of depressurizing the internal space of the liquid crystal cell, and after the depressurizing step, an immersing step of immersing the opening of the liquid crystal cell in the vacuum container with a liquid crystal material. And a normal pressure step of bringing the vacuum container to normal pressure, and a substrate transfer step of transferring the pair of substrates to the outside of the vacuum container while the opening is immersed in a liquid crystal material. I do.

Further, the liquid crystal injection device of the present invention provides a liquid crystal injection device having an interior space of a liquid crystal cell comprising a pair of substrates arranged opposite to each other and a sealing material formed between the pair of substrates except for an opening. A liquid crystal injection device for injecting a liquid crystal material, comprising: a vacuum container; a liquid crystal storage member for storing the liquid crystal material; an elevating device for raising and lowering the liquid crystal storage member; a transport mechanism for transporting a liquid crystal cell; And a coupling mechanism for integrally coupling the transfer mechanism and the transport mechanism.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a liquid crystal display device and a liquid crystal injection device according to the present invention will be described below with reference to the accompanying drawings.

Embodiment 1 FIG. 1 shows a configuration diagram of a liquid crystal injection device. The main part of the liquid crystal injection device is constituted by a vacuum container and a liquid crystal cell transfer mechanism.

In FIG. 1, reference numeral 60 denotes a vacuum vessel, P denotes a liquid crystal cell, 64 denotes a transport member of a transport mechanism for transporting a cassette 63 for accommodating the liquid crystal cells P in a groove (not shown) in parallel, 62
Reference numeral denotes a liquid crystal storage member for storing a liquid crystal material 65, and reference numeral 61 denotes a loading plate of an elevating device for raising and lowering the liquid crystal storage member 62, which have the same configuration as the conventional liquid crystal injection device shown in FIG.

In the liquid crystal injection device according to one embodiment of the present invention, in addition to the above-described structure, a pair of permanent magnets 1 is provided to integrally connect the liquid crystal storage member 62 and the transport mechanism of the liquid crystal cell P.
And a coupling mechanism consisting of a connecting member 2 attached to the transport member 64 and a liquid crystal storage connecting member 3 attached to the liquid crystal storage member 62.
In order to reduce the shock at the time of suction by the transport mechanism of the liquid crystal cell P, a shock buffering mechanism including the electromagnet 4 is provided on the loading plate 61.

Next, an embodiment of a method for manufacturing a liquid crystal injection device and a liquid crystal display device will be described.

First, as shown in FIG.
The cassette 63 containing the cassette is loaded into the cassette loading port (not shown).
Is carried into the vacuum vessel 60 from the above.

Then, the vacuum container 60 is evacuated while the liquid crystal injection port (not shown) of the liquid crystal cell P is not immersed in the liquid crystal material 65 (see FIG. 2B).

Then, as shown in FIG. 2C, after reaching a predetermined degree of vacuum, the loading plate 61 is raised, and the liquid crystal injection port of the liquid crystal cell P is immersed in the liquid crystal material 65.

At this time, the connecting member 2 and the liquid crystal storage connecting member 3 are attracted to each other by the magnetic Coulomb force of the permanent magnet 1.

In the present invention, the permanent magnet 1 has at least three permanent magnets, which are sufficient for adsorbing and transporting the liquid crystal storage member 62.
The material is not particularly limited as long as it can provide a magnetic Coulomb force of about kg / cm ² , and various materials can be used.

It is to be noted that there is a concern that the liquid crystal material 65 may be spilled or the liquid crystal cell P may be chipped at the end due to the impact of the attraction force based on the magnetic Coulomb force. Therefore, in order to avoid such a problem, a magnetic field generated by the current-controlled electromagnet 4 is generated in the liquid crystal storage member 62 for a predetermined time against the attraction force of the liquid crystal storage member 62. That is, the liquid crystal injection port of the liquid crystal cell P is immersed in the liquid crystal material 65,
Until the permanent magnet 1 and the liquid crystal reservoir connecting member 3 come into contact with each other, the liquid crystal reservoir member 62 is attracted by the electromagnet 4 with an attractive force equal to or greater than the magnetic Coulomb force of the permanent magnet 1 (a specific method is as follows). See below). With this configuration, since the liquid crystal storage member 62 is fixed by suction, it is possible to avoid a suction impact and to prevent mechanical damage such as spilling of the liquid crystal material 65 and chipping of an end of the liquid crystal cell P.

Next, as shown in FIG. 3 (a), the vacuum in the vacuum vessel 60 is released to atmospheric pressure. Since the liquid crystal injection port is immersed in the liquid crystal material 65, the internal space of the liquid crystal cell P is
Even if the vacuum is released, the reduced pressure state can be maintained, whereby the liquid crystal material 65 is injected using the pressure difference between the atmospheric pressure and the internal space of the liquid crystal cell P.

Then, after stopping the current supply to the electromagnet 4, the loading plate 61 is lowered (FIG. 3).
(B)). Then, as shown in FIG. 3C, the conveying member 64 of the conveying mechanism is driven by the magnetic Coulomb force of the permanent magnet 1.
The cassette 63 is lifted in a state where the liquid crystal storage member 62 is connected to the cassette 63.

Next, the liquid crystal storage member 62 is transported together with the cassette 63 to the outside of the vacuum container 60 by the magnetic Coulomb force of the permanent magnet 1. Since the liquid crystal injection port is immersed in the liquid crystal material 65 even during the transportation of the liquid crystal cell P, the injection of the liquid crystal material 65 is continued.

The separation of the liquid crystal storage member 62 and the transport mechanism of the liquid crystal cell P is performed at a point where the filling of the liquid crystal material 65 is completed (the completion point can be estimated), and an electromagnet (not shown) different from the electromagnet 4 is used. ) Comes into contact with the liquid crystal storage member 62, whereby the liquid crystal storage member 62 is attracted by an attraction force equal to or greater than the magnetic Coulomb force of the permanent magnet 1 (a specific method will be described later).

In the present embodiment, the step of transporting the liquid crystal cell and the step of injecting the liquid crystal can be performed simultaneously, so that the production tact can be improved. In addition, the vacuum container of the liquid crystal injection device
Since the time occupied by one cassette can be reduced, the operation rate of the liquid crystal injection device can be increased.

Next, the details of the coupling mechanism will be described with reference to FIGS. 4 and 5, and the details of the shock absorbing mechanism will be described with reference to FIG.

FIG. 4 is an enlarged view of the coupling mechanism, and FIG. 5 is a sectional view taken along a section line AB in FIG. In FIG.
Reference numeral 62 denotes a rectangular liquid crystal storage member for storing a liquid crystal material, and reference numeral 3 denotes a liquid crystal storage member 62 which is joined to the periphery of the lower surface of the liquid crystal storage member 62 to hold and transport the liquid crystal cell and the cassette 63 together, for example, by screwing. A liquid crystal storage connecting member of a magnetic material, 1 is a pair of permanent magnets, 64 is a non-magnetic material conveying member,
Reference numeral 2 denotes a magnetic connecting member joined to the transport member 64. In FIG. 5A, 1a, 1b, 1c and 1d
Is a permanent magnet, 3 is a liquid crystal reservoir connecting member, and 2 is a connecting member. FIG. 5B shows the separated state of the liquid crystal reservoir connecting member 3 and the connecting member 2, wherein the liquid crystal reservoir connecting member 3 and the permanent magnets 1 a and 4 b are joined, and the connecting member 2 and the permanent magnet 1 c. 1d is joined, and both the liquid crystal reservoir connecting member 3 and the connecting member 2 are made of a ferromagnetic material. As a result, as shown in FIG. 5A, the liquid crystal reservoir connecting member 3 and the connecting member 2 are attracted by magnetic force to be integrally connected.

FIG. 6 is an enlarged view of the shock absorbing mechanism. In FIG. 6, 4 is an electromagnet, 5 is a magnetic yoke plate, 61 is a non-magnetic loading plate, 62 is a non-magnetic liquid crystal storage member, and 6 is provided between the liquid crystal storage member 62 and the yoke plate 5. It is a plate member made of a magnetic material. here,
The electromagnet 4 and the loading plate 61 and the liquid crystal storage member 62 and the plate-like member 6 are respectively joined. Therefore, when the magnetic field of the electromagnet 4 is generated (ON), an attractive force is generated between the liquid crystal storage member 62 and the electromagnet 4 via the plate member 6. If the attraction force is larger than the attraction force of the permanent magnet 1, the liquid crystal storage member 62 is fixed to the electromagnet 4 when the liquid crystal storage member 62 is coupled to the liquid crystal cell transfer mechanism. The problem of giving a shock is eliminated. Further, since the electromagnetic attraction force of the liquid crystal storage member 62 is larger than the attraction force of the permanent magnet, after filling the liquid crystal material, the liquid crystal storage member 62 and the electromagnet 4 are brought into contact again to erase the magnetic field of the electromagnet 4 ( OFF), the liquid crystal storage member 62 can be separated from the liquid crystal cell transport mechanism.

The magnetic poles of the permanent magnet 1 are changed as shown in FIG.
If the S pole and the N pole are arranged in a cross, magnetic flux leakage is reduced, and the life of the magnet can be extended. In particular,
Regarding the permanent magnet 1, the S pole and the N pole as shown in FIG.
When the poles are arranged in a cross, the magnetic flux is generated by the magnetic members 2, 3
7, the magnetic flux leakage is reduced.
If the S pole and the N pole are opposed to each other as shown in FIG. 3B, the magnetic members 2 and 3 are polarized to the N pole or the S pole, and the magnetic flux leaks to the outside. Therefore, in order to extend the life of the permanent magnet 1, it is preferable to arrange the S pole and the N pole crosswise.

Since the liquid crystal storage member 62 transported together with the liquid crystal cell is not large enough to remodel the transport mechanism in terms of weight and space, it also has the advantage that the existing transport mechanism can be used as it is.

Embodiment 2 In this embodiment, instead of the magnetic Coulomb force of a permanent magnet,
This embodiment differs from the first embodiment in that the elastic force of the hook with spring is used (other operations are the same as those of the first embodiment).
Is the same as Hereinafter, the connection of the liquid crystal storage member and the transport mechanism of the liquid crystal cell by the hook with a spring and the separation thereof will be described.

First, the connection between the liquid crystal storage member and the liquid crystal cell transport mechanism will be described.

FIG. 8 shows an integrated state of the liquid crystal storage member and the transport mechanism using a hook fitting mechanism with a spring.

In FIG. 8, P is a liquid crystal cell, 63 is a cassette for accommodating liquid crystal cells P arranged in parallel in grooves (not shown), 64 is a conveying member for conveying the cassette 63, 61 is a loading plate, and 62 is a loading plate. A liquid crystal storage member, 7 is a liquid crystal storage pedestal, 8 is a plate-shaped hook fitting as an engaging member, and 9 is a spring as an elastic member. The plate-shaped hook 8 is attached to the transport member 64 so that the lower end can move up and down, and the upper end is connected to the transport member 64 via the spring 9.

FIG. 9 shows that the liquid crystal storage member 62 is
2 shows an operation of coupling to the transport mechanism of FIG. This operation is performed after the cassette 63 is loaded into a vacuum container (not shown) of the liquid crystal injection device and the vacuum container is evacuated.

First, the cassette 63 is moved to the liquid crystal storage member 62.
(FIG. 9A). Next, the hook fitting 8 moves upward due to the elastic contraction of the spring 9 (FIG. 9B). Further, the hook fitting 8 is arranged on the bottom surface of the liquid crystal storage member 62 (FIG. 9C).

Although the spring 9 is used in the present embodiment, any other elastic member, for example, rubber, may be used as long as the member has elasticity.

According to the present embodiment, the liquid crystal storage member 62 and the transport mechanism of the liquid crystal cell P can be integrally connected by the hook fitting mechanism with the spring. The operation rate can be improved.

Next, separation of the liquid crystal storage member and the transport mechanism of the liquid crystal cell will be described.

FIG. 10 shows the separating operation of the liquid crystal storage member 62 and the transport mechanism of the liquid crystal cell P. This behavior is
This is performed after the filling of the internal space of the liquid crystal cell P with the liquid crystal material is completed while the cassette 63 is being transported. A movable pin 10 and a lift 11 are provided at the separation location, as shown in FIG. First, the hook fitting 8 is pushed up by the movable pin 10 while the liquid crystal storage member 62 is lifted by the lift 11 together with the liquid crystal cell P. Next, since the hook fitting 8 is pushed up by the movable pin 10, the liquid crystal storage member 62 is lowered together with the liquid crystal cell P as shown in FIG. Thus, the liquid crystal storage member 62 can be separated from the transport mechanism without interference between the liquid crystal storage member 62 and the hook fitting 8.

As for the contact portion of the liquid crystal storage member 62 with the hook fitting 8, as shown in FIGS. 11 to 12, a hook 12 is provided on the bottom surface of the liquid crystal storage member 62 as a hook fitting introduction portion. An introduction groove 13 that is easily engaged is provided. Thereby, the tip of the hook fitting 8 can be attached to the liquid crystal storage member 62 with high accuracy.

In this embodiment, two hooks and two hooks are provided on one side and two hooks are provided on the other side.
The number of the introduction claws and the introduction grooves is not limited to four.

[0046]

According to the invention according to claims 1 to 3,
By transporting the liquid crystal cell outside the vacuum vessel with the opening of the liquid crystal cell immersed in the liquid crystal material, the liquid crystal injection step and the liquid crystal cell transport step can proceed simultaneously. Therefore, the tact time of liquid crystal injection and the operation rate of the vacuum vessel can be improved.

According to the inventions according to the fourth to seventh aspects, there is provided a coupling mechanism for integrally coupling the liquid crystal reservoir for storing the liquid crystal and the transport mechanism for transporting the liquid crystal cell.
Since the liquid crystal injecting step and the liquid crystal cell transporting step can proceed at the same time, it is possible to improve the liquid crystal injecting tact and the operation rate of the vacuum vessel.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining an overall configuration of a liquid crystal injection device according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the liquid crystal injection device according to the first embodiment.

FIG. 3 is a diagram for explaining an operation of the liquid crystal injection device of the first embodiment.

FIG. 4 is a detailed view of a coupling mechanism.

FIG. 5 is a sectional view taken along line BB in FIG. 4;

FIG. 6 is a cross-sectional view for explaining an impact relaxation mechanism.

FIG. 7 is an enlarged cross-sectional view of a permanent magnet and a member, illustrating the effect of reducing magnetic flux leakage caused by a difference in arrangement of permanent magnets.

FIG. 8 is a cross-sectional view for explaining an overall configuration of a liquid crystal injection device according to a second embodiment of the present invention.

FIG. 9 is a diagram illustrating a coupling operation of the liquid crystal injection device according to the second embodiment.

FIG. 10 is a diagram illustrating a separation operation of the liquid crystal injection device according to the second embodiment.

FIG. 11 is a side view of a state in which a plate-shaped hook is engaged with a liquid crystal storage member.

FIG. 12 is a sectional view taken along line CC in FIG. 11;

FIG. 13 is a front view for explaining the configuration of a liquid crystal cell.

FIG. 14 is a cross-sectional view taken along line AA for explaining a configuration of a liquid crystal cell.

FIG. 15 is a sectional view showing a liquid crystal injection device used in a conventional vacuum injection method.

FIG. 16 is an explanatory view showing a state before liquid crystal material is injected in a conventional vacuum injection method.

FIG. 17 is an explanatory view showing a state in which a liquid crystal material is injected in a conventional vacuum injection method.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 permanent magnet 2 connecting member 3 liquid crystal storage connecting member 4 electromagnet 5 yoke plate 6 plate member 7 liquid crystal storage base 8 hook metal fitting 9 spring 10 movable pin 11 lift 12 tip claw 13 introduction groove 60 vacuum container 61 loading plate 62 liquid crystal storage member 63 cassette 64 transport member 65 liquid crystal material P liquid crystal cell

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuo Yoshida 997 Miyoshi, Nishigoshi-cho, Kikuchi-gun, Kumamoto Prefecture Inside Advanced Display Co., Ltd.

Claims (7)

[Claims] 1. A liquid crystal material is injected into an inner space of a liquid crystal cell comprising a pair of substrates arranged opposite to each other and a sealing material formed between the pair of substrates except for an opening. A method for manufacturing a liquid crystal display device for manufacturing a display device, comprising: a pressure reducing step of reducing the internal space of the liquid crystal cell after loading the liquid crystal cell into a vacuum container; and A dipping step of dipping the opening of the liquid crystal cell in a liquid crystal material, a normal pressure step of setting the vacuum container to a normal pressure, and a step of dipping the pair of substrates in the vacuum container with the opening dipped in the liquid crystal material. And a substrate transporting step of transporting the liquid crystal display to the outside of the liquid crystal display device. 2. The method for manufacturing a liquid crystal display device according to claim 1, wherein, simultaneously with the immersion step, the liquid crystal cell transport mechanism and the liquid crystal storage member storing the liquid crystal material are integrally joined by suction. 3. The method for manufacturing a liquid crystal display device according to claim 1, wherein a liquid crystal storage member storing a liquid crystal material is held in an opening of the liquid crystal cell by a coupling mechanism simultaneously with the immersion step. 4. A liquid crystal injection for injecting a liquid crystal material into an internal space of a liquid crystal cell comprising a pair of substrates arranged opposite to each other and a sealing material formed between the pair of substrates except for an opening. An apparatus, comprising: a vacuum container, a liquid crystal storage member for storing a liquid crystal material, an elevating device for raising and lowering the liquid crystal storage member, a transport mechanism for transporting a liquid crystal cell, and integrally integrating the liquid crystal reservoir member and the transport mechanism. A liquid crystal injection device comprising a coupling mechanism. 5. The liquid crystal injection device according to claim 4, wherein said coupling mechanism includes a pair of permanent magnets. 6. The liquid crystal injection device according to claim 5, wherein the lifting device is provided with an impact buffering mechanism for reducing the attraction force of the pair of permanent magnets. 7. The liquid crystal injection device according to claim 4, wherein the coupling mechanism comprises an engaging member that engages with the liquid crystal storage member, and an elastic member that elastically moves the engaging member up and down.