JP2011186026A - Liquid crystal display device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device and a manufacturing method for suppressing the contact of an aligned film formed by flexographic printing and a sealing material. <P>SOLUTION: In the liquid crystal display device 10 in which a pair of substrates 11, 16 are stuck together by a sealing material 21 so as to face each other, and liquid crystal 27 is enclosed in the inside, the aligned films 14, 19 are formed respectively on the surfaces on the side of the liquid crystal 27 of the pair of substrates 11, 16, and liquid-repellent films 15, 20 are formed between the end parts of the oriented films 14, 19 and an area 21a where the sealing material 21 is formed. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention relates to a liquid crystal display device and a manufacturing method thereof, and more particularly, to a liquid crystal display device and a manufacturing method thereof that can suppress contact between the alignment film and a sealing material even when the alignment film is formed using a flexographic printing method.

The flexographic printing method is a relief printing method using a relief printing plate and a liquid printing material made of an elastic material such as rubber or flexible resin, and is also used when forming an alignment film of a liquid crystal display panel. .

However, in the flexographic printing method, the relief printing plate of the relief printing plate is made of an elastic material such as rubber or resin, so that printing misalignment occurs due to elastic deformation of the relief printing and uneven adhesion of the liquid printing material at the same time as printing. There is. The positional accuracy in the direction parallel to the printing direction of this printing deviation is generally ±
It is about 400 μm. For this reason, if the flexographic printing method is employed when forming the alignment film of the liquid crystal display panel, the alignment film may be formed over the seal formation region due to the positional accuracy of the flexographic printing method. And, if the sealing material is formed on the alignment film, there is a risk of insufficient adhesion between the substrate and the sealing material, and considering the moisture absorption risk in aged use, the sealing material and the alignment film It is preferable to avoid this contact as much as possible.

On the other hand, in recent liquid crystal display devices, the narrowing of the frame has progressed in order to enlarge the display screen. However, when the flexographic printing method is used as a method for forming the alignment film, it is possible to seal the alignment film from the alignment film. The design distance up to this point cannot be made very narrow, and it has been difficult to meet demands such as a narrow frame.

By the way, the following Patent Document 1 discloses an invention of a flexographic printing method with little coating unevenness. That is, in the flexographic printing method described in Patent Document 1 below, a plate material to be mounted on the plate cylinder is provided with unevenness uniformly on the entire surface of the plate, and hot melt ink is filled in the recesses of the plate material, The ink is transferred to a printing medium. According to the flexographic printing method disclosed in Patent Document 1 below, unevenness of ink adhesion generated in the preceding stage is obtained by using a plate material with unevenness uniformly provided on the entire surface of the plate and storing ink in the recesses. As a result, it is said that the hot melt ink can be solidly applied to a printing medium without uneven application.

JP-A-9-131959

However, even with the flexographic printing method disclosed in Patent Document 1, it is difficult to completely suppress the elastic deformation of the relief printing plate, and because the liquid printing material is used, unevenness in the amount of adhesion is also completely suppressed. It is difficult to suppress misalignment printing.

Therefore, as a result of various studies to solve the above-described problems of the prior art, the present inventors have formed a liquid-soluble film between the end of the alignment film and the region where the sealing material is formed. It has been found that forming an alignment film on a liquid-repellent film due to printing misalignment makes it difficult to form a sealing material on the alignment film, thereby completing the present invention. Is.

That is, an object of the present invention is to provide a liquid crystal display device in which the alignment film is prevented from coming into contact with the sealing material even when the alignment film is formed by a flexographic printing method, and a manufacturing method thereof.

In order to achieve the above object, the liquid crystal display device of the present invention comprises:
In a liquid crystal display device in which a pair of substrates are bonded so as to face each other and a liquid crystal is sealed inside,
An alignment film is formed on each of the liquid crystal side surfaces of the pair of substrates,
A lyophobic film is formed between an end of the alignment film and a region where the sealing material is formed.

An alignment film is formed on the surface of the liquid crystal display device array substrate and the color filter substrate on the side in contact with the liquid crystal, and then a sealing material for applying the substrates together is applied. At this time, if the alignment film is formed up to the region where the seal material is formed, the seal material formed on the alignment film may cause problems such as insufficient adhesion and moisture absorption during aged use. Therefore, in order to avoid the formation of the alignment film up to the region where the sealing material is formed, a certain distance is formed between the end of the alignment film and the region where the sealing material is formed. However,
In order to achieve narrowing of the frame for expanding the display area of the liquid crystal display device, it is preferable that the distance between the alignment film and the sealing material is narrow.

In the liquid crystal display device of the present invention, the lyophobic film is disposed between the end of the alignment film and the region where the sealing material is formed. By doing in this way, the forming material of the alignment film applied on the lyophobic film is easily peeled off, and the formation of the alignment film in the region where the sealing material is formed is suppressed. In addition, a liquid crystal display device with a high manufacturing yield can be provided. Further, by forming the lyophobic film, the alignment film and the sealing material can be arranged close to each other, so that a liquid crystal display device with a narrow frame can be provided.

Further, in the liquid crystal display device according to the present invention, the lyophobic film includes a mounting region on which a side of the pair of substrates on which the liquid crystal injection port is formed and a driver IC for driving the liquid crystal are mounted. Can be formed on the side excluding the side on which is formed.

In the liquid crystal display device of the present invention, no lyophobic film is formed on the side where the liquid crystal inlet is formed and the side where the mounting region is formed. Since the side where the liquid crystal injection hole and the mounting region are formed does not contribute to the special narrow frame, a sufficient gap can be provided between the end portion of the alignment film and the region where the sealing material is formed. . For this reason, according to the liquid crystal display device of the present invention, since the lyophobic film is formed only on the side that contributes to the narrowing of the frame, it is not necessary to use a useless material and to provide an inexpensive liquid crystal display device. Can do.

In the liquid crystal display device according to the present invention, the lyophobic film may be formed in an annular shape so as to surround the alignment film.

According to the liquid crystal display device of the present invention, since the lyophobic film is formed in an annular shape so as to surround the alignment film, it is possible to suppress the formation of the sealing material on the alignment film at all sides. Therefore, it is possible to provide a liquid crystal display device with a better manufacturing yield.

In the liquid crystal display device according to the present invention, it is preferable that the liquid-repellent film is a fluororesin film.

The fluororesin film has a liquid-repellent property with respect to both an aqueous solvent and an organic solvent. According to the liquid crystal display device of the present invention, since the liquid-repellent film is formed of a known fluororesin film, it is possible to easily obtain a liquid crystal display device that exhibits the above-mentioned effects satisfactorily.

In order to achieve the above object, a method for manufacturing a liquid crystal display device according to the present invention is a method for manufacturing a liquid crystal display device according to any one of the above, and the following steps (1) to (4) are sequentially performed. It is characterized by providing.
(1) A step of forming a lyophobic film between a region where the alignment film is to be formed and a region where the sealing material is formed on each of the opposing surfaces of the pair of substrates,
(2) A step of forming the alignment film by flexographic printing in the alignment film formation scheduled regions on the facing surfaces of the pair of substrates,
(3) a step of removing the alignment film attached on the liquid-repellent film;
(4) A step of applying a sealing material to a region where the sealing material is formed on one of the pair of substrates, arranging the pair of substrates to face each other and bonding them, and disposing a liquid crystal therein.

Flexographic printing has advantages such as easy printing, continuous production, and effective for high-speed coating since the relief flexographic printing plate is made of an elastic material. On the other hand, there is a demerit that printing deviation may occur due to elastic deformation of the relief printing plate or uneven adhesion of the liquid printing material. However, in the liquid crystal display device of the present invention, even if the alignment film is formed by flexographic printing, a liquid-repellent film is formed between the alignment film and the sealing material. Also, the region where the sealing material is formed is not formed. Further, since the alignment film is rubbed, the influence of the uneven adhesion amount is reduced. Therefore, according to the liquid crystal display device of the present invention, the alignment film can be formed easily and at high speed, and the alignment film is formed up to the region where the sealing material is formed even if the alignment film is misaligned. Is suppressed,
Furthermore, even if the design distance from the end of the alignment film to the region where the sealing material is formed is reduced, the contact between the alignment film and the sealing material can be suppressed.

1A is a plan view of the liquid crystal display device of Embodiment 1, and FIG. 1B is a cross-sectional view taken along line IB-IB in FIG. 1A. FIG. 3 is a plan view illustrating a state in which the color filter substrate of the liquid crystal display device of Embodiment 1 is transmitted. 3A is an enlarged view of the IIIA portion of FIG. 2, and FIG. 3B is an enlarged view of the IIIB portion of FIG. 1B. 4A to 4E are cross-sectional views illustrating the manufacturing process of the liquid crystal display device according to the first embodiment. 5A is a plan view corresponding to FIG. 2 of the liquid crystal display device of Embodiment 2, and FIG. 5B is an enlarged view of the VB portion of FIG. 5A. 6A is a plan view corresponding to FIG. 2 of the liquid crystal display device of Embodiment 3, and FIG. 6B is a plan view of the liquid crystal display device of Embodiment 4 corresponding to FIG.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the embodiments and the drawings. However, the embodiment described below is used in order to embody the technical idea of the present invention.
The mode liquid crystal display device will be described as an example, and the present invention is not intended to be limited to the FFS mode liquid crystal display device described in this embodiment, and the present invention falls within the scope of the claims. It can equally be applied to the other embodiments included. In each drawing used for the description in this specification, each layer and each member are displayed in different scales so that each layer and each member can be recognized on the drawing. However, it is not necessarily displayed in proportion to the actual dimensions.

[Embodiment 1]
First, the configuration of the FFS mode liquid crystal display device according to the first embodiment will be described with reference to FIGS. As shown in FIGS. 1A and 1B, the liquid crystal display device 10 of Embodiment 1 includes an array substrate 11 in which various wirings are formed on a first transparent substrate 12 made of glass or the like, and a second transparent substrate made of glass or the like. A color filter substrate 14 on which a color filter or the like is formed is arranged oppositely. The array substrate 11 and the color filter substrate 16 are bonded together with a sealing material 21 formed so as to surround the peripheral portion, and the liquid crystal 27 is formed in the space formed by the array substrate 11, the color filter substrate 14 and the sealing material 21. Is enclosed.

A portion surrounded by the sealing material 21 and filled with the liquid crystal 27 is a display region 25, and an outside of the display region 25 is a non-display region 26. The array substrate 11 has a slightly larger size than the color filter substrate 16 so that a predetermined space projecting portion is formed when the array substrate 11 is arranged opposite to the color filter substrate 16. This overhanging portion is a mounting region 12a in which a driver IC 22 for driving the liquid crystal 27 is disposed.
It has become.

On the first transparent substrate 12 such as glass, the array substrate 11 is formed by repeatedly forming and patterning a metal film, an insulating film, a resin film, etc., and various wirings such as signal lines and scanning lines, and thin film transistors as switching elements ( TFT: Thin Film Transistor, ITO (Indium Thin Oxide)
) And IZO (Indium Zinc Oxide), etc., a lower electrode made of a transparent conductive material, an interelectrode insulating film,
An upper electrode made of a transparent conductive material such as ITO or IZO is provided. The configurations of the lower electrode, the interelectrode insulating film, the upper electrode, and the like are not different from those of a well-known FFS mode liquid crystal display device. Therefore, in FIG. It is.

A first alignment film 14 is formed on the side of the first structure 13 that contacts the liquid crystal 27, and further, between the end of the first alignment film 14 and the region where the sealing material 21 is formed. The first lyophobic film 15 is formed in an annular shape along the end of the first alignment film 14. Then, the first alignment film 14 is rubbed in a predetermined direction to form the array substrate 11 of the first embodiment. In the display region 25 of the array substrate 11, a photo spacer (for maintaining a cell gap between the two substrates)
(Not shown) is formed.

In addition, the color filter substrate 16 includes a light shielding layer, a color filter layer, an overcoat layer, and the like by repeatedly forming and patterning a metal film, a resin film, an insulating film, and the like on the second transparent substrate 17 such as glass. It is formed. In FIG. 1B, these are collectively referred to as the second structure 18.
It is said that. Similarly to the array substrate 11 described above, the second alignment film 19 is formed on the side of the second structure 18 in contact with the liquid crystal 27, and the end portion of the second alignment film 19 and the sealing material 21 are formed. Between the regions, the second lyophobic film 20 is formed in an annular shape along the end of the second alignment film 19. The second alignment film 19 is rubbed so as to be orthogonal to the rubbing direction of the first alignment film 14 formed on the array substrate 11, for example, so that the color filter substrate 16 of the first embodiment is obtained.

Then, the sealing material 21 is applied to either the array substrate 11 or the color filter substrate 16, and the array substrate 11 and the color filter substrate 16 are bonded together. Thereafter, the liquid crystal 27 is injected from the liquid crystal injection port 23 formed of the sealing material 21, the liquid crystal injection port 23 is sealed with the sealant 24, and the driver IC 22 and the like are installed in the mounting region 12a. The liquid crystal display device 10 is completed. A polarizing plate (not shown) is formed on the opposite side of the first transparent substrate 12 and the second transparent substrate 17 that is in contact with the liquid crystal.

Next, an alignment film, a lyophobic film, and a sealing material formed in the liquid crystal display device 10 of Embodiment 1 will be described with reference to FIGS. In addition, although the lyophobic film is formed on both sides of the array substrate and the color filter substrate, the array substrate will be described below as a representative.

As shown in FIG. 2, in the liquid crystal display device 10 of Embodiment 1, the first lyophobic film 15 is formed between the end portion of the first alignment film 14 and the region where the sealing material 21 is formed. Yes. The specific arrangement of the first alignment film 14, the first lyophobic film 15, and the sealing material 21 will be described in detail in the order of formation with reference to FIG. In FIG. 4, the configuration of the first transparent substrate 12 is not shown.

First, after the formation up to the first structure 13 of the array substrate 11 is completed, the designed first alignment film 1 is formed.
The position where the end portion 4 is formed (corresponding to “alignment film formation planned region” of the present invention) and the sealing material 21
The first lyophobic film 15 is formed between the region 21a where the film is formed (see FIG. 4A). This first
Since the liquid-soluble film 15 is formed with a certain degree of accuracy, for example, screen printing or photolithography is used. The first liquid-repellent film 15 may be formed of a fluororesin film that has liquid-repellent properties for both aqueous and organic solvents.

Next, the first alignment film 14 is formed on the display region 25 of the array substrate 11 by flexographic printing (see FIG. 4B). As described above, flexographic printing is easy to print, but there is a risk of print misalignment, and this print misalignment is generally ± 400 μm. If the alignment film is formed up to the region 21a where the sealing material is formed due to this printing misalignment, the sealing material may be superimposed on the alignment film. It will be easy to peel off. Therefore, conventionally, a sufficient gap has been provided between the end portion of the alignment film and the region where the sealing material is formed in consideration of this printing deviation.

However, in the liquid crystal display device 10 according to the first embodiment, even if the first alignment film 14 is formed by flexographic printing, the first lyophobic film 15 is formed, so printing is performed by flexographic printing as shown in FIG. 4D. Even if a shift occurs and the first alignment film 14 is formed so as to overlap the first liquid-repellent film 15, the first alignment film 14 on the first liquid-repellent film 15 is not fixed, so that the sealing material 21 is applied. It can be easily removed before (see FIG. 4E). Therefore, even if a printing misalignment of the first alignment film 14 occurs,
It can suppress that the 1st alignment film 14 is formed to the area | region 21a in which the sealing material 21 is formed. In addition, since the first alignment film 14 is rubbed, even if the first alignment film 14 formed by flexographic printing has uneven adhesion amount, the influence is reduced.

Thereafter, a rubbing process is performed on the first alignment film 14, and a sealing material 21 for bonding the array substrate 11 and the color filter substrate 16 is applied by a dedicated seal dispenser (see FIG. 4C). At this time, since the formation of the first alignment film 14 is suppressed in the region 21 a where the sealing material 21 is formed, the sealing material 21 may be formed so as to overlap the first alignment film 14. Very little.

Therefore, according to the liquid crystal display device of the present invention, the alignment film can be formed easily and at high speed, and the alignment film is formed up to the region where the sealing material is formed even if the alignment film is misaligned. Further, even when the design distance from the end of the alignment film to the region where the seal material is formed is reduced, the contact between the alignment film and the seal material can be suppressed. Therefore,
It is possible to provide a liquid crystal display device with a high manufacturing yield even in a narrow frame region.

[Embodiment 2]
In the liquid crystal display device 10 of the first embodiment, the case where the lyophobic films 15 and 20 are formed in an annular shape along the alignment films 14 and 19 has been described, but in the liquid crystal display device 10A of the second embodiment, the lyophobic film is a liquid crystal. The case where it forms in sides other than the side in which the injection hole 23 and the mounting area | region 12a are formed is demonstrated.
Note that the liquid crystal display device 10A according to the second embodiment is different from the liquid crystal display device 10 according to the first embodiment only in the range in which the liquid-repellent film is formed. Reference numerals are assigned and detailed description is omitted. Hereinafter, as in the case of the first embodiment, the array substrate will be described as a representative.

As shown in FIGS. 5A and 5B, in the liquid crystal display device 10A according to the second embodiment, the lyophobic film 15A is used.
Is formed only on the side of the array substrate 11 other than the side where the liquid crystal injection hole 23 and the mounting region 12a are formed.

The side corresponding to the liquid crystal injection port 23 and the mounting region 12a is a flexographic printing position system ± 400.
Since it is an influencer having a size that is clearly larger than μ, it hardly contributes to narrowing the frame, and a sufficient gap should be provided between the end of the alignment film and the region where the sealing material is formed. it can. For this reason, it is not always necessary to form a lyophobic film on the side corresponding to the liquid crystal injection port 23 and the mounting region 12a. Therefore, according to the liquid crystal display device of the second embodiment, since the lyophobic film 15A is formed only on the side that contributes to the narrowing of the frame, the liquefied film forming material is not wasted, and the liquid crystal is inexpensive. A display device can be provided.

[Embodiment 3 and Embodiment 4]
In the liquid crystal display devices 10 and 10A of the first and second embodiments, the case where the liquid crystal injection port 23 is formed has been described. However, the present invention is not limited to this, and the liquid crystal display devices of the third and fourth embodiments shown in FIG. In addition, it can be applied to those formed by the ODF method. In FIG. 6, as in the case of the first embodiment, the array substrate is described as a representative, and the specific configuration of the color filter substrate is not shown.

At this time, as in the liquid crystal display device 10B of the third embodiment shown in FIG. 6A, the lyophobic film 15B may be formed in an annular shape, and as in the liquid crystal display device 10C of the fourth embodiment shown in FIG. 6B. ,
The lyophobic film 15C may be formed on a side other than the side where the mounting region 12a is formed. In FIG. 6, the liquid crystal display device 10 of the first embodiment is different from the liquid crystal display device 10 in that the liquid crystal injection port 23 is not formed and the range in which the lyophobic films 15 and 20 are formed is different. 1
The components common to those of the liquid crystal display device 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

By doing in this way, the part in which the liquid crystal injection port 23 as shown in the liquid crystal display device 10 of Embodiment 1 was formed can also contribute to the narrowing of the frame, and further, the lyophobic film By being formed, the same effects as those of the first and second embodiments can be obtained.

In the first to fourth embodiments, the lateral electric field type FFS mode liquid crystal display device has been described. However, the present invention is not limited to this, but a lateral electric field type IPS (In-Plane Switchi).
ng) mode liquid crystal display device, TN (Twisted Nematic) mode, VA
(Vertical Alignment) mode, MVA (Multi-domain Vertical Alignment) mode, and other vertical electric field type liquid crystal display devices can be equally applied.

10, 10A, 10B, 10C: Liquid crystal display device 11: Array substrate 12: First transparent substrate 12a: Mounting region 13: First structure 14: First alignment film 15, 15A, 15B,
15C: first liquid-soluble film 16: color filter substrate 17: second transparent substrate 18: second
Structure 19: Second alignment film 20: Second liquid-repellent film 21: Sealing material 21a: Sealing material forming region 22: Driver IC 23: Liquid crystal injection port 24: Sealing material 25: Display region 2
6: Non-display area 27: Liquid crystal

Claims (5)

In a liquid crystal display device in which a pair of substrates are bonded so as to face each other and a liquid crystal is sealed inside,
An alignment film is formed on each of the liquid crystal side surfaces of the pair of substrates,
A liquid crystal display device, wherein a liquid-repellent film is formed between an end portion of the alignment film and a region where the sealing material is formed. The lyophobic film is formed on the sides excluding the side on the side where the liquid crystal injection port of the pair of substrates is formed and the side on which the mounting region on which the driver IC for driving the liquid crystal is mounted is formed. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is formed. The liquid crystal display device according to claim 1, wherein the lyophobic film is formed in an annular shape so as to surround the alignment film. The liquid crystal display device according to claim 1, wherein the liquid-repellent film is a fluororesin film. It is a manufacturing method of the liquid crystal display device in any one of Claims 1-4, Comprising: The following (1)-(
4. A method for manufacturing a liquid crystal display device, comprising the steps of 4) sequentially.
(1) A step of forming a lyophobic film between a region where the alignment film is to be formed and a region where the sealing material is formed on each of the opposing surfaces of the pair of substrates,
(2) A step of forming the alignment film by flexographic printing in the alignment film formation scheduled regions on the facing surfaces of the pair of substrates,
(3) a step of removing the alignment film attached on the liquid-repellent film;
(4) A step of applying a sealing material to a region where the sealing material is formed on one of the pair of substrates, arranging the pair of substrates to face each other and bonding them, and disposing a liquid crystal therein.

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