KR20030095655A - Method for manufacturing liquid crystal display device - Google Patents

Abstract

PURPOSE: A method for manufacturing a liquid crystal display is provided to reduce time required for forming a liquid crystal layer by uniformly filling liquid crystal at an inner area of a sealant before bonding substrates. CONSTITUTION: An aligning material is applied on a thin film transistor(TFT) substrate and a color filter substrate(100). An aligning process is executed to make liquid crystal particles have regular directivity. The TFT substrate and the color filter layer are cleaned. An ultraviolet hardening type sealant(120) is applied on the TFT substrate in a closed type. Liquid crystal(110) is dropped on the TFT substrate. The liquid crystal is uniformly filled in an area corresponding to an inner area of the sealant. The TFT substrate and the color filter substrate are bonded with each other.

Description

Manufacturing method of liquid crystal display device {METHOD FOR MANUFACTURING LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly, to a method for manufacturing a liquid crystal display device to which a liquid crystal dropping method is applied.

As the information society develops, the demand for display devices is increasing in various forms, and in recent years, the LCD (Lipuid Crystal Display Device), PDP (Plasma Display Panel), ELD (Electro Luminescent Display), and VFD (Vacuum Fluorescent) Various flat panel display devices such as displays have been studied, and some of them are already used as display devices in various devices.

Among them, liquid crystal displays are the most widely used, replacing the cathode ray tubes for mobile image display devices because of their excellent image quality, light weight, thinness, and low power consumption. In addition to the same mobile type, various developments have been made for television monitors.

Such liquid crystal displays are largely manufactured through an array process, a color filter process, a liquid crystal cell process, and the like.

The array process is a process of forming a thin film transistor (TFT) and a pixel electrode on a first substrate by repeating deposition, photolithography, and etching processes.

In the color filter process, a black matrix is formed on the second substrate to prevent light leakage in regions other than the region where the pixel electrode is formed, and red and green colors are formed using dyes or pigments. After manufacturing a blue color filter, it is a process of forming an indium tin oxide (ITO) film for common electrodes.

The liquid crystal cell process maintains a constant cell gap between the first substrate and the second substrate by using a spacer, joins both substrates using a seal material, and then cuts the unit panel and injects liquid crystal to complete the liquid crystal cell. It is a process.

Hereinafter, a liquid crystal injection process of the conventional liquid crystal cell process will be described with reference to the drawings.

1 is a schematic view showing a method of injecting liquid crystal into a unit panel using a conventional vacuum injection method.

As shown in FIG. 1, first, the container 30 containing the liquid crystal material 25 is positioned in the chamber 20, and then the inside of the chamber 20 is kept in a vacuum state so as to be in the liquid crystal 25 material or the container 30. Remove moisture from the inner wall and remove bubbles.

Subsequently, after immersing or contacting the unit panels 40 in the container 30, nitrogen (N ₂ ) gas is introduced into the chamber 20 to raise the pressure in the chamber to atmospheric pressure. The liquid crystal material 25 is injected into the unit panel 40 by the difference between the pressure and the pressure in the chamber 20.

In this case, since the seal material applied for bonding the substrate is patterned on the unit panel 40 to form the liquid crystal injection hole, the liquid crystal material 25 is injected into the unit panel 40 through the injection hole.

Thereafter, when the liquid crystal 25 is filled in the unit panel 40, the liquid crystal cell is completed by performing an encapsulation process of sealing the injection hole.

However, since the vacuum injection method injects the liquid crystal into the unit panel due to the pressure difference, it takes a long time to inject the liquid crystal and thus there is a problem in that productivity is lowered.

In addition, when manufacturing a large-area liquid crystal display device, the liquid crystal is not completely injected into the unit panel to generate an unfilled region of the liquid crystal, or an overfill region may occur, which may cause a defect in image reproduction.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method of manufacturing a liquid crystal display device having improved productivity by forming a liquid crystal layer within a short time.

Another object of the present invention is to provide a method of manufacturing a liquid crystal display device in which an overfilled or unfilled region of a liquid crystal is not generated by uniformly distributing the liquid crystal.

1 is a schematic view showing a method of injecting liquid crystal into a unit panel using a conventional vacuum injection method.

2A and 2B are schematic views showing a method of manufacturing a liquid crystal display using a liquid crystal dropping method according to the present invention.

3 is a manufacturing process diagram for explaining a method for manufacturing a liquid crystal display device according to an embodiment of the present invention.

4 is a cross-sectional view for explaining a liquid crystal filling method of the present invention.

Explanation of symbols on the main parts of the drawings

100: second substrate 110: liquid crystal

120: seal material 200: injector

In order to achieve the above object, the present invention provides a method comprising the steps of providing a first substrate and a second substrate; Applying a sealant in a closed manner on any one of the first substrate and the second substrate; Dropping liquid crystal onto any one of the first substrate and the second substrate; Uniformly filling the liquid crystal in an area corresponding to an inner region of the seal material; And bonding the first substrate and the second substrate to each other.

That is, according to the present invention, instead of injecting the liquid crystal by the pressure difference after joining the first substrate and the second substrate, the manufacturing time is reduced by dropping the liquid crystal onto the first substrate or the second substrate and then joining the two substrates together. It is shortened and productivity is improved.

In addition, the liquid crystal is not filled or unfilled by performing the liquid crystal filling process so that the liquid crystal is uniformly distributed after the liquid crystal dropping.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2A and 2B are schematic views illustrating a method of manufacturing a liquid crystal display device using the liquid crystal dropping method according to the present invention.

As can be seen in FIG. 2A, a UV curable seal material 3 having a frame shape without a liquid crystal injection hole is applied to the TFT substrate 1 to a predetermined thickness, and the inside of the seal material 3 (thin film transistor array portion). ), The appropriate amount of liquid crystals 2 is evenly added. In this case, the liquid crystal 2 is uniformly doped by a predetermined amount with a constant pitch and pattern using a syringe (Syringe, 10).

Next, as shown in Fig. 2B, the color filter substrate 5 is placed on the TFT substrate 1 on which the seal material 3 is printed in a vacuum chamber (not shown), and then bonded.

Then, although not shown in the drawing, restoring the inside of the vacuum chamber to atmospheric pressure causes the bonded TFT substrate 1 and the color filter substrate 5 to pressurize the substrate due to the pressure difference between the chamber and the substrate. ) And the color filter substrate 5 to form a liquid crystal layer. Then, the liquid crystal display device is manufactured by curing the seal material 3 by irradiating the application area of the seal material 3 while moving the UV light source.

Since the liquid crystal dropping method directly drops the liquid crystal onto the substrate for a short time, not only can the liquid crystal layer formation of a large area liquid crystal display device proceed very quickly, but also only the required amount of liquid crystal is directly dropped onto the substrate. Since it is possible to minimize the consumption of the liquid crystal display device has the advantage that can significantly reduce the manufacturing cost.

FIG. 3 is a manufacturing process diagram for explaining a manufacturing method of the liquid crystal display device of the present invention, and FIG. 4 is a cross-sectional view illustrating the liquid crystal front coating method of FIG. 3.

As shown in FIG. 3, first, a first substrate (TFT substrate) and a second substrate (Color Filter substrate) are provided.

Although not shown in the drawing, a plurality of gate lines arranged in one direction at predetermined intervals on the first substrate and a plurality of data lines arranged at regular intervals in a direction perpendicular to the gate lines are provided. ) And a plurality of thin film transistors and pixel electrodes respectively formed in the matrix pixel region defined by the gate line and the data line.

The second substrate includes a black matrix layer for blocking light except for the pixel region, a color filter layer including three primary colors of red, green, and blue, and the pixel electrode. Together with these, a common electrode for driving a liquid crystal is formed. In addition, a columnar spacer may be formed on the surface of the second substrate to correspond to the gate line and the data line on the first substrate with a height of about 3.5 μm in order to increase the area of the liquid crystal display device.

In the first and second substrates configured as described above, the liquid crystal display device is implemented by the following liquid crystal cell process.

First, after the alignment material is coated on the first substrate and the second substrate, an alignment process is performed simultaneously so that the liquid crystal molecules have uniform orientation. The alignment process proceeds in order of cleaning before application of the alignment film (20S), alignment film printing (21S), alignment film firing (22S), alignment film inspection (23S), and rubbing (24S).

Next, the first substrate and the second substrate on which the alignment process has been performed are cleaned (25S), and then a closed seal material having no injection hole is formed to bond the second substrate to the outside of the pixel area of the first substrate at a predetermined interval. It is apply | coated 26S in a frame shape on a 2nd board | substrate. Then, on the first substrate, silver (Ag) is coated in a dot shape (27S) for electrical connection with the common electrode on the second substrate. In this case, the seal material may be formed on any one of the first substrate and the second substrate, and in the in-plane switching mode (IPS) mode, the pixel electrode and the common electrode are formed on the first substrate. (Ag) It is not necessary to form a dot.

Next, the liquid crystal is dripped onto the sealing material inner region on the second substrate (28S). The liquid crystal dropping may drop the liquid crystal by a spray method or a liquid crystal dispensing device. In addition, the liquid crystal may be dropped into a region corresponding to the inner region of the seal member on the first substrate.

However, when the liquid crystal and the seal material are formed on the same substrate, an imbalance occurs between the process between the substrate where the liquid crystal and the seal material are formed and the substrate that does not form the process, and the process takes a lot of time. Even if contaminants are formed in the seal material before bonding, the substrate may not be cleaned, and thus the liquid crystal and the seal material may be formed on different substrates.

Subsequently, the liquid crystal dropped in the sealing material inner region is uniformly filled (29S). At this time, the filling method of the liquid crystal enables the liquid crystal dropped on the substrate to be uniformly applied to a desired area by using an injector for injecting inert gas or nitrogen (N ₂ ) gas. In this case, the inert gas and the nitrogen gas are gases having non-reactivity with the liquid crystal.

That is, as shown in FIG. 4, when the liquid crystal 110 dropped on the second substrate 100 is taken as an example, the injector 200 maintains a constant gap with the second substrate 100. Approached to the liquid crystal 110, the liquid crystal 110 can be evenly spread evenly by spraying nitrogen gas to evenly filled inside the sealing material 120 of the second substrate 100 can be filled with the liquid crystal. Make sure

Next, as shown in FIG. 3, the first substrate and the second substrate are bonded (30S). At this time, since the liquid crystal is uniformly filled on the first substrate or the second substrate in advance, a pressing process for filling the liquid crystal dropped between the first substrate and the second substrate facing each other using a vacuum bonding machine as in the prior art is performed. It is not necessary to simply perform the bonding process simply. Thereby, the problem of the lack of the conventional liquid crystal drop amount and the problem of gravity failure due to the liquid crystal drop amount adjustment failure can be prevented beforehand.

Subsequently, the seal material is cured to form a liquid crystal disc (31S), and then the liquid crystal disc is cut for each panel (32S).

After that, each cut panel is polished (33S), and then final inspection (34S) such as appearance and electrical failure is performed to complete the liquid crystal display device.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

The manufacturing method of the liquid crystal display device of the present invention described above has the following effects.

First, after the liquid crystal is dropped, the liquid crystal is uniformly filled in the inner region of the seal material and the first and second substrates are bonded together, thereby shortening the liquid crystal layer formation time and preventing the problem of the shortage of the liquid crystal due to the liquid crystal dropping amount. have.

Second, after dropping the liquid crystal, it is possible to uniformly diffuse the dropped liquid crystal in the desired area through a simple process, it is possible to shorten the overall process time.

Third, by forming the liquid crystal disc with an optimal amount of liquid crystal, it is possible to prevent the failure of gravity due to the pressure difference between the substrate and the substrate.

Claims (7)

Providing a first substrate and a second substrate; Applying a sealant in a closed manner on any one of the first substrate and the second substrate; Dropping liquid crystal onto any one of the first substrate and the second substrate; Uniformly filling the liquid crystal in an area corresponding to an inner region of the seal material; And And attaching the first substrate and the second substrate to each other. The method of claim 1, Filling the liquid crystal uniformly And a gas which does not react with the liquid crystal while spraying a gas that does not react with the liquid crystal while maintaining a constant gap with the substrate on which the liquid crystal is dropped. The method of claim 2, The gas which does not react with the liquid crystal is an inert gas or nitrogen gas manufacturing method of the liquid crystal display device. The method of claim 1, Providing the first substrate Forming a plurality of gate lines and data lines on the first substrate to define pixel regions crossing each other; And forming a plurality of thin film transistors and pixel electrodes in the pixel regions defined by the gate lines and the data lines, respectively. The method of claim 1, Providing the second substrate And a color filter layer formed between the black matrix layer and the black matrix layer on the second substrate to represent three primary colors of red, green, and blue, and a common electrode for operating a liquid crystal in common with the pixel electrode. Method of manufacturing a liquid crystal display device. The method of claim 1, And forming silver (Ag) dots in a common voltage supply line on the first substrate or the second substrate. The method of claim 1, The dropping of the liquid crystal may include any one of a spray method and a drop method using a liquid crystal dispensing device.