JP3086732B2 - Manufacturing method of liquid crystal display element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a liquid crystal display device.

[0002]

2. Description of the Related Art Conventionally, one of the processes of manufacturing a liquid crystal display element has been described.
For example, rubbing, in which an alignment film formed on a transparent substrate is rubbed in one direction with a cloth or the like to perform alignment processing, is well known. Here, rubbing means forming an alignment film on a transparent substrate in order to obtain the alignment direction of liquid crystal molecules, and forming groove-shaped uneven portions in this alignment film in a predetermined direction.
The quality of the display quality of the liquid crystal display element is determined by the result of the rubbing, and the yield of the liquid crystal display element in the manufacturing process is determined. Therefore, in this rubbing process,
It is desired to form a uniform groove-shaped uneven portion on the alignment film surface. By the way, in the conventional method of manufacturing a liquid crystal display element, before rubbing, as shown in FIG. 5, the display area is slightly larger than a display area 53 on each transparent substrate such as a CF (color filter) substrate 51 and an electrode substrate 52. An alignment film 54 is formed in the region. This region is referred to as a liquid crystal filling region 55 (hatched portion). After that, rubbing is performed on the alignment film 54.

[0006] As shown in FIG. 6, when rubbing the CF substrate 51 in a predetermined direction, for example, an oblique direction (arrow) using a cloth or the like, the alignment film 54 in the liquid crystal filling region 55 is cut off at the time of cell formation. A difference in pressing force due to rubbing occurs at the boundary with the substrate portion 56 extending outside the liquid crystal filling region 55 and in the vicinity thereof. Further, when the portion where the pressure difference occurs is divided by drawing a distribution line C on the alignment film, a central portion 57 (a portion where the pressing force is almost constant) of the alignment film 54 and a peripheral portion 58 (a portion where the pressing force is strong) of the alignment film 54 are divided. ). In this case, the distribution line C may fall within the display area 53.

In such a situation, for example, when the alignment film 54 is continuously rubbed with a cloth or the like, the cloth or the like that rubs the peripheral edge portion 58 (the part where the pressing force is strong) of the alignment film 54 and the way of getting dirty are used. Will change. That is, at the peripheral edge portion 58 of the alignment film, the depth of the groove-shaped uneven portion becomes deep at the beginning of use of the cloth, and the depth of the groove-shaped uneven portion becomes shallow as the cloth comes loose. Become stable. For example, when the uneven portion becomes shallow at the portion of the distribution line C that overlaps the display region 53, the liquid crystal molecules of the liquid crystal material filled in that portion cause poor alignment. A display defect (display unevenness) such as a thinned portion is caused. As a result, the yield decreases in the process of manufacturing the liquid crystal display element.

[0005]

As described above, in the above-mentioned conventional method for manufacturing a liquid crystal display element, an alignment film is formed in a liquid crystal filling region of each transparent substrate, and the alignment film is rubbed.
There has been a problem that poor alignment may occur in the display region, and the yield of the manufacturing process of the liquid crystal display element is reduced.

The present invention has been made in order to solve such problems, and at least a display area of each transparent substrate can be rubbed with a uniform pressing force. As a result, the yield of the manufacturing process of the liquid crystal display element is improved. It is another object of the present invention to provide a method for manufacturing a liquid crystal display element which can improve productivity.

[0007]

The present invention SUMMARY OF THE INVENTION To achieve the above object, a step of forming a first alignment layer on the first substrate, on the outside of the display area and the display area, the first 1) rubbing the alignment film; and
A step of bonding the sealant and opposed to the substrate, after said first and second substrates are bonded含Wa, the first at least a portion of the first alignment film outside the display region Removing together with the substrate of
The alignment film has at least an area where the sealant is formed.
It is characterized by being formed excluding a part .

[0008]

In the method of manufacturing a liquid crystal display device according to the present invention, at least at the time of rubbing, the transparent substrate extends outside the display region. It becomes a flat surface.

When the entire surface of the alignment film of the transparent substrate is rubbed, a difference is generated in the rubbing pressing force at the peripheral edge of the transparent substrate, so that groove-shaped uneven portions are formed unevenly. However, this peripheral portion is a portion that is cut during cell formation, and has no relation when the liquid crystal display element is completed.

On the other hand, the rubbing pressing force is applied almost uniformly to the liquid crystal filling region (central portion) slightly larger than the display region of the transparent substrate, so that the alignment film in this region has uniform groove-shaped uneven portions. It is formed. Then, if a liquid crystal material is filled in this region after the cell is formed, the orientation direction of the liquid crystal molecules in this region can be obtained well.

As a result, in the manufacturing process of the liquid crystal display element,
Display defects are reduced, and the yield is improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a liquid crystal display device according to an embodiment of the present invention will be described below with reference to the drawings. FIGS. 1, 2, 3 and 4 are diagrams showing the procedure for manufacturing this liquid crystal display device.

In the manufacturing method of this embodiment, as shown in FIG. 1, a TF is first placed on a transparent substrate (hereinafter referred to as an electrode substrate 1).
A display area 2 composed of a T array or the like is formed, and a sealant application section 3 and a lead-out electrode section 4 are provided in the vicinity of the display area 2.
To form Since the liquid crystal material is filled in the area surrounded by the sealant application section 3, this area is referred to as a liquid crystal filled area 5. Therefore, the liquid crystal filling area 5 is the display area 2
Is slightly wider than Subsequently, except for the sealant application portion 3 and the extraction electrode portion 4 of the electrode substrate 1, the liquid crystal filling region 5 of the electrode substrate 1 and a substrate portion extending outside the liquid crystal filling region 5 (hereinafter, referred to as a “substrate portion”).
This substrate portion is an unnecessary portion that is cut during cell formation, and is referred to as an unnecessary substrate 6). An alignment film 7 is formed by using a printing method or the like by using a polyimide or the like on almost the entire surface including the unnecessary substrate 6; Bake at about 180 ° C. Note that the alignment film 7 is not formed on the sealant application portion 3 in order to maintain the adhesive strength, and the alignment film 7 is not formed on the extraction electrode portion 4 for electrical connection with another substrate. .

Subsequently, except for the sealant application portion 3 of the CF (color filter) substrate 8 and the extraction electrode portion 4 of the electrode substrate 1 which are arranged opposite to the electrode substrate 1, the unnecessary substrate 6 including the unnecessary substrate 6 is substantially removed. After forming an alignment film 7 on the entire surface,
It is fired in the same manner as the electrode substrate 1. As a result, each substrate has a substantially flat surface.

Next, the alignment film 7 including the unnecessary substrate 6 of both substrates is used.
Is subjected to a rubbing treatment. That is, as shown in FIG.
Rubbing is performed while pressing the entire surface of the alignment film 7 of the CF substrate 8 with a cloth or the like in a predetermined direction, for example, in an oblique direction (arrow direction).

At this time, in the alignment film 7 formed on the unnecessary substrate 6, a difference occurs in the pressing force of the cloth at the peripheral portion A, and the groove-shaped uneven portion formed in this portion has the shape (depth). Becomes unstable.

On the other hand, a uniform groove-shaped uneven portion is formed on the alignment film 7 in the liquid crystal filling region 5 because a pressing force of a cloth or the like is applied substantially uniformly. The rubbing process is performed on the electrode substrate 1 in the same manner. In the case of the TN type, the rubbing direction is orthogonal to the electrode substrate 1 and the CF substrate 8.

Then, as shown in FIG. 3, a transfer 9 for electrically connecting the electrode substrate 1 and the CF substrate 8 is applied to the CF substrate 8, and a sealant 11 such as epoxy resin is applied to the electrode substrate 1. The two substrates are bonded together via spacer beads 12 so that the alignment films 6 face each other. The spacer beads 12 have a diameter of 5 μm.
The degree is used.

Thereafter, as shown in FIG. 4, the unnecessary substrate 6 of each substrate is cut from the effective outer dimension line B of the cell (a position near the outside of the transfer 9), and an injection port (not shown) is formed. The liquid crystal material 13 in the liquid crystal filling region 5 from the injection port
Is filled and the injection port is sealed, thereby forming a liquid crystal cell 14 in which the alignment direction of liquid crystal molecules is excellent. That is, since the unnecessary substrate 6 is cut, there is no problem in the completed liquid crystal cell 14 irrespective of the state of the groove-shaped uneven portion formed on the unnecessary substrate 6.

As described above, according to the method of manufacturing the liquid crystal display element of the present embodiment, the alignment film 7 is formed on almost the entire surface of the electrode substrate 1 and the CF substrate 8 and the entire surface of the alignment film 7 is rubbed, whereby the pressing force of the cloth is The difference occurs in the peripheral portion A of the substrate. However, since the peripheral portion A is unnecessary for the liquid crystal cell 14, no problem occurs in the liquid crystal cell 14.

On the other hand, the alignment film 7 in the liquid crystal filling region 5 of both substrates
In this case, a uniform groove-shaped uneven portion is formed, so that the orientation direction of the liquid crystal molecules can be favorably obtained.

As a result, in the manufacturing process of the liquid crystal display element,
Display defects and the like are reduced, the yield of liquid crystal display elements is improved, and productivity is improved.

The present invention can be used for various liquid crystal display devices such as a simple matrix liquid crystal display device and an active matrix liquid crystal display device.

[0024]

As described above, according to the method for manufacturing a liquid crystal display device of the present invention, an alignment film is formed on almost the entire surface of a transparent substrate, and the entire alignment film is rubbed. In this method, a uniform groove-shaped uneven portion is formed, and the orientation direction of the liquid crystal molecules can be favorably obtained.

As a result, in the manufacturing process of the liquid crystal display element,
The yield is improved, and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a view showing a first step of a manufacturing procedure of a liquid crystal display element according to an embodiment of the present invention.

FIG. 2 is a view showing a second step of the procedure for manufacturing the liquid crystal display element according to one embodiment of the present invention.

FIG. 3 is a view showing a third step of the manufacturing procedure of the liquid crystal display element of one embodiment of the present invention.

FIG. 4 is a view showing a fourth step of the procedure for manufacturing the liquid crystal display element of one embodiment of the present invention.

FIG. 5 is a plan view showing an alignment film formation state of a conventional liquid crystal display element.

FIG. 6 is a plan view showing a state after a rubbing process of a conventional liquid crystal display element.

[Explanation of symbols]

 1 electrode substrate 2 display area 5 liquid crystal filling area 7 alignment film 8 CF substrate 14 liquid crystal cell

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-60513 (JP, A) JP-A-56-119115 (JP, A) JP-A-57-41614 (JP, A) 284419 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G02F 1/1337 500 G02F 1/13 101

Claims (6)

(57) [Claims] A step of forming a first alignment film on a first substrate outside a display area and the display area; a step of rubbing the first alignment film; A sealant is applied to face the first substrate .
A step of bonding match Ri, after the first and second substrates are bonded含Wa, removing with the first substrate at least part of an outer side of the first alignment film in the display area, Having the first arrangement
The facing film has at least one of the regions where the sealant is formed.
A method for manufacturing a liquid crystal display element, wherein the method is formed excluding portions . 2. The method according to claim 1, wherein the first substrate is electrically connected to the outside.
And the first alignment film has at least one of the extraction electrode portions.
2. The method as claimed in claim 1, wherein the part is formed excluding a part.
Method for manufacturing a liquid crystal display element. 3. Between the first substrate and the second substrate
Electrically connecting the first substrate and the second substrate
Is formed, and the first alignment film is formed in a region where the transfer is formed.
Characterized by being formed excluding at least a part of the region
A method for manufacturing a liquid crystal display device according to claim 1. 4. The first substrate includes a thin film transistor.
The liquid crystal display device according to claim 1, wherein
Production method. 5. The method according to claim 1, wherein the first alignment film is formed by a printing method.
2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is formed.
Manufacturing method. 6. A display area and said display on a second substrate
Forming a second alignment film outside the region;
Rubbing the alignment film of the second alignment film , wherein the second alignment film is formed in a region where the sealant is formed.
A contract formed excluding at least a part thereof.
The method for producing a liquid crystal display device according to claim 1.