JP3853777B2 - Method for manufacturing liquid crystal display device and liquid crystal injection device - Google Patents

Description

  The present invention relates to a manufacturing method of a liquid crystal display device and a liquid crystal injection device using the manufacturing method.

  In the manufacture of a liquid crystal display device, there is a liquid crystal injection process in which a uniform gap is formed over the entire surface between a pair of stacked substrates by spacers having a diameter of about 4 μm dispersed on the substrate surface, and a liquid crystal material is injected into the gap. . This liquid crystal injection process is positioned as an important process for improving the yield in the production line because it is necessary to suppress the generation of bubbles in the gap of micron order and to reliably fill the liquid crystal material. Yes.

  Next, after explaining the liquid crystal cell, an outline of a typical liquid crystal injection method (vacuum injection method) will be described. As shown in FIGS. 13 to 14, the first transparent insulating substrate 50 and the second transparent insulating substrate 51 of the liquid crystal cell P are each provided with electrodes 52 and 53 in a predetermined pattern on the surface in contact with the liquid crystal material. It has been. 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 addition, in order to fill the internal space with the liquid crystal material in the liquid crystal injection process, an injection port 56 to which no seal material is applied is formed in a part of the seal material 55. Further, the sealing material 55 is mixed with a silica material having a predetermined diameter which plays the same role as the spacer 54.

  As an injection device used in a conventional liquid crystal injection method, as shown in FIG. 15, a loading plate 61, a liquid crystal reservoir member 62, and a liquid crystal can be moved up and down in a vacuum vessel 60 (the entire configuration of the vacuum vessel is not shown). A conveying member 64 for conveying the cassette 63 that stores the cell P is provided. First, as shown in FIG. 16, the inside of the vacuum vessel 60 is evacuated 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 reservoir member 62, thereby the internal space 66 of the liquid crystal cell P. Is set to a vacuum state of, for example, a degree of vacuum of about 1 Pa. As shown in FIG. 17, if the inside of the vacuum vessel 60 is brought to atmospheric pressure after the tip of the liquid crystal injection port 56 is immersed in the liquid crystal material 65, the pressure in the internal space 66 of the liquid crystal cell P (vacuum reduced pressure state) The liquid crystal material 65 is filled in the internal space 66 of the liquid crystal cell P due to the pressure difference from the atmospheric pressure.

  Such a vacuum injection method is excellent in injection reliability and can inject an expensive liquid crystal material without waste. There is a manufacturing apparatus that uses this vacuum injection method to perform a series of steps in an in-line manner from liquid crystal cell degassing, defoaming, and injection port sealing (see Patent Document 1).

JP-A-5-307160

  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 viscosity resistance of the liquid crystal material increases, and 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 decrease in production tact.

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

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

  In view of the above circumstances, the present invention provides a manufacturing method of a liquid crystal display device and a liquid crystal injection device capable of improving the production tact of the vacuum injection method and improving the equipment operation rate of the liquid crystal injection device. For the purpose.

  The method of manufacturing a liquid crystal display device according to the present invention includes a liquid crystal in an internal space of a liquid crystal cell including 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 display device manufacturing method for injecting a material to manufacture a liquid crystal display device, wherein after the liquid crystal cell is carried into a vacuum vessel, a pressure reducing step for reducing the internal space of the liquid crystal cell; and Thereafter, in the vacuum vessel, the liquid crystal reservoir member in which the liquid crystal material is stored is lifted by the lifting device to immerse the liquid crystal cell opening in the liquid crystal material, and simultaneously with the immersion step, the liquid crystal cell is transported. A step of coupling the mechanism and the liquid crystal reservoir member by adsorption of a pair of permanent magnets, a step of relaxing the adsorption force of the pair of permanent magnets by an impact mitigation mechanism provided in the lifting device, and the vacuum vessel at atmospheric pressure Normal pressure A step of lowering the lifting device after releasing the impact mitigating mechanism, and a substrate transporting step of transporting the pair of substrates to the outside of the vacuum vessel while the opening is immersed in a liquid crystal material. It is characterized by including.

  Further, the liquid crystal injection device of the present invention provides a liquid crystal material in 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 excluding the opening. A liquid crystal injection device for injecting a vacuum container, a liquid crystal reservoir member for storing a liquid crystal material, a lifting device for raising and lowering the liquid crystal reservoir member, a transport mechanism for transporting a liquid crystal cell, and the liquid crystal reservoir member and the transport mechanism And a shock absorbing mechanism for relaxing the attractive force of the pair of permanent magnets.

  Furthermore, the liquid crystal injection device of the present invention provides a liquid crystal material in 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 the opening. A liquid crystal injection device for injecting a vacuum container, a liquid crystal reservoir member for storing a liquid crystal material, a lifting device for raising and lowering the liquid crystal reservoir member, a transport mechanism for transporting a liquid crystal cell, and the liquid crystal reservoir member and the transport mechanism A coupling mechanism that couples the liquid crystal storage member when the liquid crystal storage member ascends, retracts to a space that does not interfere with the operation of the liquid crystal storage member, and when the liquid crystal storage member descends It comprises an engaging member that engages with the liquid crystal reservoir member, and an elastic member that controls the movement of the engaging member.

  According to the invention, the liquid crystal injection step and the liquid crystal cell transfer step can proceed simultaneously by transporting the liquid crystal cell outside the vacuum vessel while the opening of the liquid crystal cell is directly immersed in the liquid crystal material. The liquid crystal can be injected efficiently, and the liquid crystal injection tact can be improved and the equipment operation rate of the vacuum vessel can be improved. In addition, by directly immersing the opening of the liquid crystal cell in the liquid crystal material of the liquid crystal reservoir member, contamination from the peripheral portion can be prevented and the production yield can be improved.

  In addition, it has a coupling mechanism that combines a liquid crystal reservoir for storing liquid crystal and a transport mechanism for transporting the liquid crystal cell. And improvement of the operation rate of the vacuum vessel.

  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 injecting apparatus is composed of a vacuum container and a liquid crystal cell transport mechanism.

  In FIG. 1, 60 is a vacuum container, P is a liquid crystal cell, 64 is a transport member of a transport mechanism that transports a cassette 63 that stores the liquid crystal cell P in parallel in a groove (not shown), and 62 stores a liquid crystal material 65. A liquid crystal reservoir member 61 is a loading plate of an elevating device that raises and lowers the liquid crystal reservoir member 62, and has the same configuration as the conventional liquid crystal injection device shown in FIG.

  In the liquid crystal injection device according to an embodiment of the present invention, in addition to the above-described configuration, the liquid crystal reservoir member 62 and the liquid crystal cell P are attached to the pair of permanent magnets 1 and the transport member 64 in order to integrally connect the transport mechanism. In order to alleviate the impact at the time of adsorption of the liquid crystal reservoir member 62 and the transport mechanism of the liquid crystal cell P, the coupling mechanism is composed of the connecting member 2 and the liquid crystal reservoir connecting member 3 attached to the liquid crystal reservoir member 62. An impact buffer mechanism made of the electromagnet 4 is provided on the loading plate 61.

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

  First, as shown in FIG. 2A, the cassette 63 containing the liquid crystal cell P is carried into the vacuum container 60 from a cassette carry-in port (not shown).

  Then, the vacuum container 60 is evacuated without immersing the liquid crystal injection port (not shown) of the liquid crystal cell P in the liquid crystal material 65 (see FIG. 2B).

  Next, as shown in FIG. 2C, after reaching a predetermined degree of vacuum, the loading plate 61 is raised, and the liquid crystal inlet of the liquid crystal cell P is brought into contact with the liquid crystal reservoir member 62 that stores the liquid crystal material 65. Directly immersed in the liquid crystal material 65.

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

The permanent magnet 1 is not particularly limited as long as it can provide a magnetic Coulomb force of at least about 3 kg / cm ² sufficient to attract and convey the liquid crystal reservoir member 62 in the present invention. Various types can be used.

  Incidentally, there is a concern about problems such as spillage of the liquid crystal material 65 or chipping of the end of the liquid crystal cell P due to the impact of the attractive 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 reservoir member 62 for a predetermined time against the attractive force of the liquid crystal reservoir member 62. That is, until the liquid crystal injection port of the liquid crystal cell P is immersed in the liquid crystal material 65 and the permanent magnet 1 and the liquid crystal reservoir connecting member 3 are brought into contact, the electromagnet 4 attracts more than the magnetic coulomb force of the permanent magnet 1. Then, the liquid crystal reservoir member 62 is sucked (a specific method will be described later). In this way, since the liquid crystal reservoir member 62 is fixed by suction, it is possible to avoid an adsorption shock and prevent mechanical damage such as spillage of the liquid crystal material 65 and chipped end portions of the liquid crystal cell P.

  Next, as shown in FIG. 3A, 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 can be kept in a reduced pressure state even when the vacuum is released, whereby the pressure between the atmospheric pressure and the internal space of the liquid crystal cell P can be maintained. The liquid crystal material 65 is injected using the difference.

  Next, after the current supply to the electromagnet 4 is stopped, the loading plate 61 is lowered (see FIG. 3B). Then, as shown in FIG. 3C, the cassette 63 is lifted with the liquid crystal reservoir member 62 coupled to the transport member 64 of the transport mechanism by the magnetic coulomb force of the permanent magnet 1.

  Next, the liquid crystal reservoir member 62 is transported together with the cassette 63 to the outside of the vacuum vessel 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 liquid crystal material 65 is continuously injected.

  The separation of the liquid crystal reservoir member 62 and the transport mechanism of the liquid crystal cell P is a point where the filling of the liquid crystal material 65 is completed (a completion point can be estimated), and an electromagnet (not shown) different from the electromagnet 4 is The contact is made with the liquid crystal reservoir member 62, thereby attracting the liquid crystal reservoir member 62 with an attractive force greater than the magnetic coulomb force of the permanent magnet 1 (a specific method will be described later).

  In the present embodiment, the transport process of the liquid crystal cell and the liquid crystal injection process can be performed simultaneously, so that the production tact can be improved. Further, since the time occupied by one cassette for the vacuum container of the liquid crystal injection device can be shortened, the operating rate of the liquid crystal injection device can be increased.

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

  4 is an enlarged view of the coupling mechanism, and FIG. 5 is a cross-sectional view taken along a cross-sectional line BB in FIG. In FIG. 4, reference numeral 62 denotes a rectangular liquid crystal reservoir member for storing liquid crystal material, and 3 denotes a liquid crystal reservoir member 62 which is joined to the periphery of the lower surface of the liquid crystal reservoir member 62 in order to transport the liquid crystal cell and the cassette 63 together. A screw-connected magnetic liquid crystal reservoir connecting member, 1 is a pair of permanent magnets, 64 is a non-magnetic conveying member, and 2 is a magnetic connecting member joined to the conveying member 64. In FIG. 5A, 1a, 1b, 1c and 1d are permanent magnets, 3 is a liquid crystal reservoir connecting member, and 2 is a connecting member. FIG. 5B shows a separated state of the liquid crystal reservoir connecting member 3 and the connecting member 2, and the liquid crystal reservoir connecting member 3 and the permanent magnets 1a and 4b are joined, and the connecting member 2 and the permanent magnet 1c, The liquid crystal reservoir connecting member 3 and the connecting member 2 are both 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 the magnetic force and are integrally coupled.

  FIG. 6 shows 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 reservoir member, and 6 is provided between the liquid crystal reservoir member 62 and the yoke plate 5. This is a magnetic plate member. Here, the electromagnet 4 and the loading plate 61 and the liquid crystal reservoir member 62 and the plate-like member 6 are joined to each other. Therefore, when the magnetic field of the electromagnet 4 is generated (ON), an attractive force is generated between the liquid crystal reservoir member 62 and the electromagnet 4 via the plate-like member 6. If this attractive force is larger than the attractive force of the permanent magnet 1, the liquid crystal reservoir member 62 is fixed to the electromagnet 4 when the liquid crystal reservoir member 62 and the liquid crystal cell transport mechanism are coupled. The problem of giving a shock is solved. Further, since the electromagnetic attracting force of the liquid crystal reservoir member 62 is larger than the attracting force of the permanent magnet, after the liquid crystal material is filled, the liquid crystal reservoir member 62 and the electromagnet 4 are brought into contact again to erase the magnetic field of the electromagnet 4 ( OFF), the liquid crystal reservoir member 62 can be separated from the transport mechanism of the liquid crystal cell.

  Further, if the magnetic poles of the permanent magnet 1 are arranged in a cross between the S poles and the N poles as shown in FIG. 5, the leakage of magnetic flux is reduced and the life of the magnet can be extended. Specifically, for the permanent magnet 1, if the S pole and N pole as shown in FIG. 7A are arranged in a cross manner, the magnetic flux passes through the magnetic members 2 and 3, so that the magnetic flux leakage is reduced. On the other hand, if the S and N poles are arranged facing each other as shown in FIG. 7B, the magnetic members 2 and 3 are polarized to the N or S poles, so that the magnetic flux leaks to the outside. End up. Therefore, in order to extend the life of the permanent magnet 1, it is preferable to arrange the S pole and the N pole in a cross arrangement.

  The liquid crystal reservoir member 62 that is transported together with the liquid crystal cell has an advantage that the existing transport mechanism can be used as it is because the transport mechanism is not significantly modified in terms of weight and space.

Embodiment 2
The present embodiment is different from the first embodiment in that the elastic force of the hook fitting with spring is used instead of the magnetic coulomb force of the permanent magnet (the other operations are the same as those of the first embodiment). Is). Hereinafter, the coupling of the liquid crystal reservoir member and the transport mechanism of the liquid crystal cell by the hook fitting with the spring and the separation thereof will be described.

  First, the coupling of the liquid crystal reservoir member and the liquid crystal cell transport mechanism will be described.

  FIG. 8 shows an integrally coupled state of the liquid crystal reservoir member using the spring-loaded hook metal fitting mechanism and the transport mechanism.

  In FIG. 8, P is a liquid crystal cell, 63 is a cassette for storing the liquid crystal cell P in parallel with a groove (not shown), 64 is a transport member for transporting the cassette 63, 61 is a loading plate, and 62 is a liquid crystal reservoir member. , 7 is a liquid crystal reservoir base, 8 is a plate-shaped hook fitting as an engaging member, and 9 is a spring as an elastic member. The plate-like hook metal fitting 8 is attached to the conveying member 64 so that the lower end portion thereof can move up and down, and the upper end portion thereof is connected to the conveying member 64 via a spring 9.

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

  First, the cassette 63 is moved in the direction of the liquid crystal reservoir member 62 (FIG. 9A). Next, the hook fitting 8 moves upward by the elastic contraction of the spring 9 (FIG. 9B). Further, the hook fitting 8 is disposed on the bottom surface of the liquid crystal reservoir member 62 (FIG. 9C).

  Although the spring 9 is used in the present embodiment, other elastic bodies such as rubber can be used as long as the members have elastic expansion and contraction.

  According to the present embodiment, the liquid crystal reservoir member 62 and the transport mechanism of the liquid crystal cell P can be integrally coupled by the spring-loaded hook metal fitting mechanism, and as in the above embodiment, the production tact can be improved and the equipment operating rate of the vacuum vessel can be improved. Improvements can be made.

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

  FIG. 10 shows the separation operation of the liquid crystal reservoir member 62 and the transport mechanism of the liquid crystal cell P. This operation is performed after the inside of the liquid crystal cell P is completely filled with the liquid crystal material while the cassette 63 is being transported. As shown in FIG. 10A, the separation pin is provided with a movable pin 10 and a lift 11. First, with the liquid crystal cell P and the liquid crystal reservoir member 62 lifted by the lift 11, the hook fitting 8 is pushed up by the movable pin 10. Next, since the hook metal fitting 8 is pushed up by the movable pin 10, the liquid crystal reservoir member 62 is lowered together with the liquid crystal cell P as shown in FIG. Thus, the liquid crystal reservoir member 62 can be separated from the transport mechanism without interference between the liquid crystal reservoir member 62 and the hook fitting 8.

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

  In this embodiment, four hooks and two introduction grooves are provided on one side and two on the other side, for a total of four. Is not limited to this.

It is sectional drawing for demonstrating the whole structure of Embodiment 1 of the liquid crystal injection device of this invention. FIG. 5 is a diagram for explaining the operation of the liquid crystal injection device according to the first embodiment. FIG. 5 is a diagram for explaining the operation of the liquid crystal injection device according to the first embodiment. It is detail drawing of a coupling mechanism. It is the BB sectional view taken on the line in FIG. It is sectional drawing for demonstrating an impact relaxation mechanism. It is a cross-sectional enlarged view of a permanent magnet and a member, Comprising: It is a figure explaining the effect of the magnetic flux leak reduction brought about by the difference in arrangement | positioning of a permanent magnet. It is sectional drawing for demonstrating the whole structure of Embodiment 2 of the liquid crystal injection device of this invention. FIG. 10 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. It is a side view of the state which engaged the plate-shaped hook metal fitting with the liquid crystal reservoir member. It is CC sectional view taken on the line in FIG. It is a front view for demonstrating the structure of a liquid crystal cell. It is an AA line sectional view for explaining the composition of a liquid crystal cell. It is sectional drawing which shows the liquid crystal injection apparatus used for the conventional vacuum injection method. It is explanatory drawing which shows the state before inject | pouring the liquid-crystal material in the conventional vacuum injection method. It is explanatory drawing which shows the state which has inject | poured the liquid-crystal material in the conventional vacuum injection method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Permanent magnet 2 Connecting member 3 Liquid crystal reservoir connecting member 4 Electromagnet 5 Yoke plate 6 Plate-like member 7 Liquid crystal reservoir base 8 Hook metal fitting 9 Spring 10 Movable pin 11 Lift 12 Tip nail 13 Introducing groove 60 Vacuum container 61 Loading plate 62 Liquid crystal reservoir member 63 Cassette 64 Transport member 65 Liquid crystal material P Liquid crystal cell

Claims (3)

A liquid crystal display device is manufactured by injecting a liquid crystal material into an internal space of a liquid crystal cell composed of a pair of substrates arranged opposite to each other and an encapsulant formed between the pair of substrates excluding the opening. A method for manufacturing a liquid crystal display device, wherein after the liquid crystal cell is carried into a vacuum vessel, a decompression step of decompressing the internal space of the liquid crystal cell, and after the decompression step, an elevator device is provided in the vacuum vessel. The liquid crystal storage member in which the liquid crystal material is stored is lifted by dipping the liquid crystal cell opening in the liquid crystal material, and at the same time as the dipping process, the liquid crystal cell transport mechanism and the liquid crystal storage member are paired with a pair of permanent magnets. A step of coupling by adsorption, a step of relaxing the attractive force of the pair of permanent magnets by an impact relaxation mechanism provided in the lifting device, a normal pressure step of bringing the vacuum vessel to normal pressure, and the impact relaxation mechanism Canceled Chi, a step of lowering the lifting device, the opening in a state dipped in the liquid crystal material, a method of manufacturing a liquid crystal display device including a substrate transfer step of transferring the pair of substrates to the outside of the vacuum container. The method of manufacturing a liquid crystal display device according to claim 1, wherein a liquid crystal reservoir member in which a liquid crystal material is stored in an opening of the liquid crystal cell is held by a coupling mechanism simultaneously with the dipping step. A liquid crystal injection device 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 excluding an opening, A vacuum vessel, a liquid crystal reservoir member that stores liquid crystal material, an elevating device that raises and lowers the liquid crystal reservoir member, a transport mechanism that transports a liquid crystal cell, and the liquid crystal reservoir member and transport mechanism are attached by adsorption of a pair of permanent magnets. A liquid crystal injection apparatus comprising: a coupling mechanism for coupling; and an impact mitigation mechanism for mitigating the attractive force of a pair of permanent magnets.

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