JPH117019A - Device and method for rubbing oriented film for liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove dirt such as dust sticking on the surface of rubbing cloth by making the flock of the rubbing cloth uniform during rubbing by the rubbing device which rubs an oriented film for liquid crystal with a rubbing roller fitted with the rubbing cloth. SOLUTION: The rubbing device A1 is equipped with a stage 72 where liquid crystal display substrates 10 and 20 provided with oriented films 16 and 26 are installed and the rubbing roller 70 to which the rubbing cloth 70a having a pile 70b is attached on its surface. A conductive plate 70 is fitted detachably to a motor 71 for roller rotation and arranged opposite the stage 72. The plate 80 is in contact with the pipe 70b above the rubbing roller 70 and its contact surface is flat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rubbing device for an alignment film for liquid crystal display and a rubbing method therefor.

[0002]

2. Description of the Related Art Hitherto, as a general alignment treatment method for a liquid crystal cell, a method described in JP-A-1-154418 has been proposed. This is an apparatus that performs a rubbing process using a rubbing roll on an alignment film provided on the surface of a liquid crystal display substrate arranged on a substrate support table. Before the rubbing process, the device is electrically rubbed using a monitor substrate. This is a rubbing treatment device provided with a means for detecting pressure and adjusting rubbing pressure.

Then, the alignment film of the liquid crystal display substrate is actually rubbed with a rubbing pressure adjusted in advance.

[0004]

However, in the above rubbing apparatus, the rubbing pressure is not directly measured during the actual rubbing of the liquid crystal display substrate, so that the surface of the rubbing cloth generated during the rubbing of the liquid crystal display substrate is not measured. There is a problem that it cannot respond to a state change. As a result, the rubbing process becomes non-uniform on the substrate surface or for each substrate, and the liquid crystal alignment also becomes non-uniform.

[0005] The inventors of the present invention have made the following inferences regarding the change in the state of the rubbing cloth surface. The surface of the alignment film on the liquid crystal display substrate has uneven unevenness in the substrate surface due to the underlying electrode pattern and the like. Therefore, when the pile (hair) on the surface of the rubbing cloth comes into contact with the surface of the alignment film, due to this uneven shape, the tip of the hair is locally directed in a direction different from the surroundings, that is, the hair level of the pile becomes uneven.

Further, before the rubbing treatment, the surface of the alignment film is sufficiently washed, but still, dirt such as dust remains locally, and the dirt adheres to the rubbing cloth surface during rubbing. It is considered that the unevenness of the fur and the adhesion of dirt make the contact with the alignment film uneven. Furthermore, at the time of rubbing, it is also conceivable that static electricity generated in the pile of the rubbing cloth takes in foreign matter in the vicinity and damages the alignment film by the foreign matter.

In view of the above problems, a first object of the present invention is to provide a rubbing device for performing a rubbing process on an alignment film for liquid crystal display using a rubbing roller having a rubbing cloth attached thereto. To align. A second object of the present invention is to remove dirt such as dust adhering to a rubbing cloth surface during rubbing while achieving the first object. Further, a third object of the present invention is to eliminate the electric charge accumulated on the rubbing cloth surface during rubbing while achieving the first and second objects.

[0008]

In order to achieve the above object, the present invention employs the following technical means. That is, according to the first aspect of the present invention, the alignment films (16, 26) provided on the surface of the liquid crystal display substrate (10, 20) disposed on the substrate support (72) are piled on the surface. In a rubbing device for performing a rubbing process by a rubbing roller (70) to which a rubbing cloth (70a) having the rubbing cloth (70b) is attached, the rubbing cloth (70a) is brought into contact with the surface of the rubbing cloth (70a) during rubbing to remove the fur of the pile (70b). A rubbing cloth adjusting member (80) for aligning is provided.

Here, the rubbing cloth adjusting member (80) for uniformly aligning the fur of the pile (70b) is, specifically, one having a flat surface in contact with the rubbing cloth (70a);
Alternatively, a repetitive uneven pattern (for example, a comb shape) having the same shape can be formed. Thereby, during rubbing, the pile (70b) of the rubbing cloth (70a) comes into contact with the rubbing cloth adjusting member (80) in addition to the liquid crystal display substrates (10, 20). Since the rubbing roller (70) is rotating in a predetermined direction, the pile (70b) comes into contact with the rubbing cloth adjusting member (80) from a predetermined direction. Therefore, the unevenness of the pile (70b) due to the uneven surface of the alignment films (16, 26) can be made uniform.

Therefore, according to the rubbing device of the present invention,
The first object of the present invention described above can be achieved, and an alignment film for liquid crystal display realizing uniform liquid crystal alignment can be provided. According to the second aspect of the present invention, in addition to the first aspect, the rubbing cloth adjusting member (80) includes a rubbing cloth (7).
0a), the pile (70)
b) a surface (80a) for removing dirt adhering to it.

As a result, during the rubbing, the surface (80a) of the rubbing cloth adjusting member (80) is brought into contact with the rubbing cloth (70).
When the pile (70b) comes into contact with the surface of (a), the fur of the pile (70b) is aligned and the pile (70b) receives an impact. The impact at the time of this contact removes dirt such as dust adhering to the pile (70b). Therefore, according to the rubbing device of the present invention, the above-mentioned second object of the present invention can be achieved, and an alignment film for liquid crystal display realizing uniform liquid crystal alignment can be provided.

According to the third aspect of the present invention, in addition to the second aspect, the rubbing cloth adjusting member (80) is provided when the rubbing cloth adjusting member (80) comes into contact with the surface of the rubbing cloth (70a).
a) a conductive member for removing static electricity; Here, as the conductive member, for example, a conductive metal such as iron or copper can be used. Thereby, in addition to the operation and effect of the second aspect, in the rubbing, the charge charged in the pile (70b) of the rubbing cloth (70a) is released, so that the foreign matter is prevented from being taken in by the static electricity. The alignment film is not damaged.

According to the rubbing device of the present invention,
The above-described third object of the present invention can be achieved, and an alignment film for liquid crystal display that realizes uniform liquid crystal alignment can be provided. Further, according to the invention of claim 4, the rubbing cloth adjusting member (80) is detachably attached to a predetermined position with respect to the rubbing roller (70). Thereby, an optimum rubbing cloth adjusting member can be selected corresponding to various liquid crystal display substrates and various rubbing cloths having different surface shapes.

According to the fifth aspect of the present invention, the rubbing cloth adjusting member (80) is attached to the rubbing roller (70) at a predetermined position, and the surface of the rubbing cloth (70a) is oriented to the alignment films (16, 26). After contact with the rubbing cloth adjusting member (80) from a predetermined direction, the pile (7)
0b) a rubbing method of an alignment film for liquid crystal display for uniforming the fur.

Thus, the first object of the present invention can be achieved, and a rubbing method for producing an alignment film for liquid crystal display having uniform liquid crystal alignment characteristics can be provided. Further, according to the fifth aspect of the present invention, it is possible to provide a method of rubbing an alignment film for a liquid crystal display which can achieve the second object of the present invention, and according to the sixth aspect of the present invention. A rubbing method for an alignment film for liquid crystal display which can achieve the third object of the present invention can be provided.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention. FIG. 1 shows a sectional structure of a liquid crystal cell 1 according to the present invention. The liquid crystal cell 1 includes an electrode substrate (liquid crystal display substrate) 10 and an electrode substrate (liquid crystal display substrate) 20 that are superposed on each other, and the two electrode substrates 10 and 20 are formed of an annular seal 30 and a spacer 50. In addition, they are bonded and supported via the bonding fine particles 40.

An antiferroelectric liquid crystal 60 is sealed between the two electrode substrates 10 and 20. The distance (cell gap) between the two electrode substrates 10 and 20 is 1.5 μm.
m. The electrode substrate 10 has a transparent substrate 11 made of, for example, glass. On the inner surface of the transparent substrate 11, a plurality of stripe-shaped transparent electrodes 14, an insulating film 15, and an alignment film 16 are sequentially laminated. . Of these, the alignment film 16 is provided on the inner peripheral side of the seal 30.

On the other hand, the electrode substrate 20 has a transparent substrate 21 made of, for example, glass, and a color filter 22 made of resin, an overcoat film 23, a plurality of stripe-shaped , A transparent electrode 24, an insulating film 25, and an alignment film 26. Among these, the color filter 22 and the alignment film 26 are provided on the inner peripheral side of the seal 30.

The plurality of transparent electrodes 24 correspond to the plurality of transparent electrodes 1.
4, the transparent electrodes 14, 24
Form a plurality of lattice pixels together with the color filter 22 and the antiferroelectric liquid crystal 60. These lattice-shaped pixels function as a display unit on which display is performed when the liquid crystal cell 1 is driven. Here, the transparent electrodes 14 and 24 are made of ITO (I
Alignment films 16 and 26 are made of polyimide resin or the like.

The transparent electrodes 14 and 24 correspond to the electrode substrate 1
The outer peripheral portions of 0 and 20 have a shape different from that of the display portion in order to establish continuity with a wiring member or the like, and the shape is not uniform when viewed over the entire surface of the substrate. Due to the non-uniform shape of the transparent electrodes 14 and 24, the alignment film 1
The surfaces of the substrates 6 and 26 also have uneven unevenness over the entire plane of the substrate.

Next, a method of manufacturing the liquid crystal cell 1 having the above configuration will be described with reference to FIG. In the original substrate forming step S1 of the electrode substrates 10 and 20, a transparent electrode 14 and an insulating film 15 are sequentially laminated on the inner surface of the transparent substrate 11. On the other hand, a color filter 22, an overcoat film 23, a transparent electrode 24, and an insulating film 25 are sequentially laminated on the inner surface of the transparent substrate 21.

In the alignment film forming step S2, the alignment film 16 is formed by offset printing on the transparent electrode 14 and the insulating film 1.
5, and an electrode substrate 10 is formed. On the other hand, the alignment film 26 is provided on the color filter 22 via the overcoat film 23, the transparent electrode 24, and the insulating film 25 to form the electrode substrate 20. In the rubbing step S3, the electrode substrate 1
The alignment film 16 provided on the surface of the substrate 0 and the alignment film 26 provided on the surface of the electrode substrate 20 are subjected to a rubbing treatment as follows.

Here, the rubbing device of the present embodiment is shown in FIG.
And FIG. FIG. 3 is a partially transparent perspective view of the rubbing device A1, and shows a cylindrical rubbing roller 70 indicated by a two-dot chain line in the figure, a roller rotation motor 71 to which the rubbing roller 70 is attached, and a variable number of rotations. A stage (substrate support base) 72 on which the electrode substrate 10 or the electrode substrate 20 is installed, and a stage moving motor 73 that moves in the rubbing direction and have a variable moving speed are provided. In FIG. 3, the roller rotation motor 71 is shown in a see-through manner.

A square plate 80, which is a rubbing cloth adjusting member of the present invention, is detachably attached to the roller rotating motor 71. The plate 80 faces the stage 72 with the rubbing roller 70 interposed therebetween, and is arranged along the longitudinal direction of the rubbing roller 70. The plate 80 is formed of a conductive member (for example, metal such as iron or copper) and is grounded through the rubbing device A1.

FIG. 4 is a sectional view of the rubbing roller 70 during rubbing and the electrode substrates 10 and 20 to be rubbed. A rubbing cloth 70a is wound around the outer periphery of the rubbing roller 70.
Are provided so that the pile 70b stands upright. The rubbing cloth 70a and the pile 70b
Is made of rayon, nylon, cotton, or the like. In addition,
The electrode substrates 10 and 20 show only the alignment films 16 and 26, and other laminated portions are omitted.

Here, the above-mentioned plate 80 is
0b, and the contact surface 80a of the plate 80 is flat. Further, the distance between the plate 80 and the rubbing roller 70 is variable (the plate 80 moves vertically in FIG. 4), so that the degree of contact between the contact surface 80a and the pile 70b can be adjusted. In the rubbing device A1 having the above configuration, the rubbing process is performed as follows.

The electrode substrate 10 or 20 is placed on the stage 72 so as to face the rubbing roller 70, and the height of the rubbing roller 70 and the stage 72 is adjusted to a predetermined value so as to obtain a predetermined rubbing strength. Subsequently, the rubbing roller 70 is rotated around the axis at a predetermined rotation speed, and the stage 72 is moved at a predetermined speed to the rubbing roller 7.
It reciprocates below 0 (in the directions of arrows D and E in FIG. 5). At this time, the pile 70b of the rubbing cloth 70a is provided in one or both directions of the forward path (D direction) and the return path (E direction).
Rubs the surface of the alignment film 16 or 26.

When the alignment films 16 and 26 are rubbed, the pile 7
In 0b, local deformation due to uneven surface of the alignment films 16 and 26, local contamination of the surfaces of the alignment films 16 and 26 by dust and the like, and electrification due to friction occur. During one rotation of the rubbing roller 70, the pile 70b rubs the alignment films 16 and 26,
0 is rubbed against the contact surface 80a. Rubbing roller 7
Since 0 is rotating in a predetermined direction, the pile 70b receives an impact in a predetermined direction upon contact. As a result, the pile 70b that has been deformed unevenly has uniform fur, and dirt such as dust adhering to the pile 70b is removed by the impact at the time of the above contact.

It should be noted that the effect of the above-described arrangement of the fur and the removal of dirt by the impact at the time of contact can be optimized by adjusting the distance between the plate 80 and the rubbing roller 70. Further, with respect to the charging of the pile 70b due to friction with the alignment films 16 and 26, the charged charges are released from the conductive plate 80, so that the foreign matter is prevented from being taken into the pile 70b by static electricity.

Then, the rubbing process is performed on the electrode substrates 10 and 20 in a predetermined direction by the above method, and the rubbing step S3 is completed. Subsequently, in the spacer / adhesion fine particle dispersing step S4, the spacers 50 and the adhesive fine particles 40 are dispersed on the alignment film of the electrode substrate 10. On the other hand, in the seal printing step S5, the seal 30 is formed in an annular shape on the outer peripheral portion of the inner surface of the electrode substrate 20 by printing a sealant. Note that a liquid crystal injection port is formed in a part of the seal 30.

Subsequently, in a superposition step S6, the electrode substrate 10 is superposed on the electrode substrate 20 via the seal 30, the spacer 50 and the adhesive fine particles 40. Then, in the seal hardening step S7, the seal 30 is hardened by applying pressure while heating the two electrode substrates 10, 20, and
A predetermined cell gap is secured. Thereafter, in the liquid crystal enclosing step S8, the antiferroelectric liquid crystal 60 is liquefied, injected and filled between the inner surfaces of the two electrode substrates 10 and 20 from the liquid crystal injection port of the seal 30, and the liquid crystal injection port is sealed. I do. Thus, the liquid crystal cell 1 is completed.

The present inventors investigated the performance of the above-mentioned liquid crystal cell 1 and confirmed that uniform liquid crystal alignment was realized in the cell plane and in each cell. By the way, according to the present embodiment, even if the pile 70b is deformed or contaminated during the rubbing process, it is possible to make the fur uniform and remove the adhered dirt by the action of the plate 80 described above. Can be.

Further, even if the pile 70b is charged during the rubbing process, the charge is released from the plate 80 before the pile 70b comes into contact with the alignment films 16 and 26. It is possible to prevent the foreign matter from damaging the alignment film. As described above, according to the present embodiment, appropriate treatment can be performed in response to the state change of the rubbing cloth 70a and the pile 70b generated during the rubbing process. Rubbing treatment can be performed, and an alignment film for liquid crystal display realizing uniform liquid crystal alignment can be provided.

According to the present embodiment, the plate 80
Is a plate having an optimal shape and material corresponding to various liquid crystal display substrates and various rubbing cloths having different surface shapes because it can be attached to and detached from the roller rotation motor 71 as a mounting portion. Can be selected. Note that the surface of the plate 80 that comes into contact with the rubbing cloth 70a is not limited to a flat surface, and may have a repetitive uneven pattern (for example, a comb shape) of the same shape.
For example, if the surface shape of the alignment film is a particularly complicated pattern and the direction of the pile is apt to change, it is effective to use a pattern having a concavo-convex pattern for forcibly aligning the fur.

The plate 80 is provided with the rubbing roller 7.
It may be curved along the circumference of 0. Thereby, the contact area and the contact time between the pile 70b and the plate 80 can be increased, and the operation and effect of the above embodiment can be realized more efficiently. Plate 8
0 may be plural. In the above embodiment,
The present invention can be applied to a liquid crystal cell using a ferroelectric liquid crystal or a nematic liquid crystal other than the antiferroelectric liquid crystal. Further, a color filter may not be provided, and a plurality of stripe-shaped partition spacer structures may be used instead of the spacers and the adhesion fine particles.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of a liquid crystal cell according to an embodiment of the present invention.

FIG. 2 is a manufacturing process diagram of the liquid crystal cell of the embodiment.

FIG. 3 is a perspective configuration diagram showing a rubbing device in the embodiment.

FIG. 4 is an operation explanatory view of the rubbing device of FIG. 3;

[Explanation of symbols]

10, 20: electrode substrate, 16, 26: alignment film, 70: rubbing roller, 70a: rubbing cloth, 70b: pile,
72: stage, 80: plate, 80a: contact surface.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masao Eibo 1-1-1, Showa-cho, Kariya-shi, Aichi Pref.

Claims (7)

[Claims] A rubbing cloth having an alignment film (16, 26) provided on a surface of a liquid crystal display substrate (10, 20) disposed on a substrate support (72) and a pile (70b) on the surface. In a rubbing device for an alignment film for liquid crystal display, wherein a rubbing process is performed by a rubbing roller (70) to which (70a) is attached, the rubbing cloth (70a) is brought into contact with the surface of the rubbing cloth (70a) during rubbing. A rubbing device for an alignment film for liquid crystal display, comprising a rubbing cloth adjusting member (80) for uniforming fur. 2. The rubbing cloth adjusting member (80) has a surface (80a) for removing dirt attached to the pile (70b) by an impact when it comes into contact with the surface of the rubbing cloth (70a). The rubbing device for an alignment film for a liquid crystal display according to claim 1, wherein: 3. The rubbing cloth adjusting member (80) is a conductive member that removes static electricity from the rubbing cloth (70a) when it comes into contact with the surface of the rubbing cloth (70a). 3. A rubbing device for an alignment film for liquid crystal display according to item 2. 4. The rubbing cloth adjusting member (80) is detachably attached to a predetermined position with respect to the rubbing roller (70). A rubbing device for an alignment film for a liquid crystal display according to item 1. 5. A rubbing cloth having a pile (70b) on an alignment film (16, 26) provided on a surface of a liquid crystal display substrate (10, 20) disposed on a substrate support (72). In a rubbing method for an alignment film for liquid crystal display, wherein a rubbing process is performed by a rubbing roller (70) having (70a) attached thereto, a rubbing cloth adjusting member (80) is attached to a predetermined position with respect to the rubbing roller (70); After the surface of the rubbing cloth (70a) is brought into contact with the alignment film (16, 26), the rubbing cloth is brought into contact with the rubbing cloth adjusting member (80) from a predetermined direction to make the pile of the pile (70b) uniform. A rubbing method for an alignment film for liquid crystal display, which is characterized by the following. 6. The dirt attached to the pile (70b) is removed by an impact when the surface of the rubbing cloth (70a) is brought into contact with the rubbing cloth adjusting member (80). 5. The method for rubbing an alignment film for a liquid crystal display according to 4. 7. The rubbing cloth adjusting member (80) is conductive, and removes static electricity from the rubbing cloth (70a) when it comes into contact with the surface of the rubbing cloth (70a). 6. The method for rubbing an alignment film for a liquid crystal display according to item 5.