JP3800056B2 - Liquid crystal device manufacturing apparatus, manufacturing method, and liquid crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to perform uniform and reliable rubbing treatment. SOLUTION: A feather tip 83 is inclined by a prescribed angle to the direction of rotation of a rubbing roll 81. The rubbing roll 81 is rotated and a stage 100 is moved to rub the surface of a substrate 101 with the feather tip 83. Since the feather tip 83 is inclined, the area of the surface of the substrate 101 rubbed by one feather tip 83 is enlarged to enhance feather density, and uniform and satisfactory alignment over the entire area of the substrate is obtained. The rubbing treatment is reliably preformed also at a part having a step. Since the inclination direction of the feather tip 83 is set up according to the twist direction of a liquid crystal, reliable rubbing treatment can be also performed at a step part. The feather tip 83 is never split by the movement of the stage. Stronger alignment regulating force can be given to an alignment layer and unevenness of feather density is hardly generated even if the rubbing is repeated, and long life of the feather tip can be realized. Thus, uniform and reliable rubbing treatment is performed.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal device manufacturing apparatus, a manufacturing method, and a liquid crystal device suitable for performing a rubbing process on an alignment film of a liquid crystal substrate.
[0002]
[Prior art]
A liquid crystal device such as a liquid crystal light valve is configured by sealing liquid crystal between two substrates such as a glass substrate and a quartz substrate. In a liquid crystal light valve, for example, thin film transistors (hereinafter referred to as TFTs) are arranged in a matrix on one substrate, a counter electrode is arranged on the other substrate, and a liquid crystal layer sealed between both substrates By changing the optical characteristics according to the image signal, it is possible to display an image.
[0003]
The TFT substrate on which the TFT is disposed and the counter substrate disposed to face the TFT substrate are manufactured separately. Both substrates are bonded together with high accuracy in the panel assembling process, and then liquid crystal is sealed therein.
[0004]
In the panel assembly process, first, an alignment film is formed on the opposing surfaces of the TFT substrate and the counter substrate manufactured in each substrate process, that is, on the surface in contact with the liquid crystal layer of the counter substrate and the TFT substrate, and then the rubbing process. Is done. Next, a seal portion serving as an adhesive is formed on the edge of one substrate. The TFT substrate and the counter substrate are bonded together using a seal portion, and are cured by pressure bonding while performing alignment. A part of the seal part is provided with a notch, and the liquid crystal is sealed through the notch.
[0005]
By forming an alignment film and performing a rubbing treatment, the alignment of liquid crystal molecules when no voltage is applied is determined. The alignment film is formed, for example, by applying polyimide (PI) with a thickness of about several tens of nanometers. By forming an alignment film on the surfaces of both substrates facing the liquid crystal layer, the liquid crystal molecules can be aligned along the substrate surface. In the rubbing process, fine grooves are formed on the surface of the alignment film to form an alignment anisotropic film, and the alignment of the liquid crystal molecules can be defined by performing a rubbing process in a certain direction on the alignment film.
[0006]
FIG. 9 is a schematic view showing a rubbing apparatus.
[0007]
A liquid crystal substrate 101 is placed on the stage 100. The stage 100 moves in the horizontal direction and transports the substrate 101. A rubbing roll 102 is disposed above the conveyance path of the stage 100. The rubbing roll 102 has a velvet-like cloth, for example, a rayon rubbing cloth 103 attached to the peripheral surface thereof. The stage 100 is conveyed while rotating the rubbing roll 102, and the entire surface of the substrate is rubbed with the rubbing cloth 103 by the rotation of the rubbing roll 102 and the conveyance of the stage 100.
[0008]
[Problems to be solved by the invention]
By the way, the rubbing cloth 103 has a rayon hair tip 104 extending from the cloth surface. The length of the bristles 104 is set longer than the distance between the rubbing roll 102 and the substrate 101 by a predetermined length in order to apply an appropriate rubbing pressure. FIG. 10 is an explanatory view of one hair tip 104 rubbing a part of the surface of the substrate 101 as viewed from the upper surface of the substrate 101. A hatched portion in FIG. 10 indicates a portion rubbed by the hair tip 104.
[0009]
When the stage 100 is conveyed while rotating the rubbing cloth 103, the hair tips 104 rub against the surface of the substrate 101 while being bent at the surface of the substrate 101. However, when the number of times of rubbing is increased, the bending of the hair tip 104 in the rotational direction becomes a habit, and the hair tip 104 is bent. Due to this folding, a uniform contact pressure cannot be maintained between the hair tip 104 and the surface of the substrate 101.
[0010]
That is, the rubbing pressure changes as the number of rubbing increases, and non-uniform rubbing processing is performed, which adversely affects the alignment film. If it does so, it will become impossible to provide sufficient orientation control force to the board | substrate 101, it will become easy to receive the influence by the influence of washing | cleaning, the elution of the solvent from a sealing material, etc., and an orientation nonuniformity will arise.
[0011]
In addition, the hair tip 104 has a relatively low restoring force, and when the rubbing process is repeated, the hair tip is locally biased and uneven hair density occurs. As a result, a portion where the rubbing strength differs depending on the position is generated, and liquid crystal tilt unevenness occurs.
[0012]
Further, as shown in FIG. 10, the surface where one hair tip 104 contacts the surface of the substrate 101 is equal to the wire diameter of the hair tip 104. The wire diameter of the bristles 104 is extremely thin, and even when a large number of bristles 104 are extended from the rubbing cloth 103, there is a relatively high possibility that a non-rubbed portion will occur.
[0013]
Moreover, when the part which has a level | step difference with the hair tip 104 is rubbed, the hair tip 104 may break into two. FIG. 11 is an explanatory view schematically showing this state. Also in this case, there is a high possibility that a portion that is not rubbed due to the crack of the hair tip 104 is generated.
[0014]
Further, the substrate 101 is not necessarily flat and may have a step around the pixel, for example. In this case, the hair tips 104 may not contact the lower corners of the stepped portion. In this case as well, alignment defects are likely to occur, and in particular, there is a problem that display defects may occur depending on the twist direction of the liquid crystal.
[0015]
The present invention has been made in view of such a problem, and the hair tip is inclined with respect to the direction perpendicular to the axis of the rubbing roll, thereby increasing the area where the hair tip contacts the substrate surface and the hair. Improves the restoring force of the tip, and also enables the rubbing tip to contact the stepped portion with certainty, thereby enabling rubbing with a uniform and stable rubbing pressure over the entire area of the substrate. An object of the present invention is to provide a manufacturing apparatus, a manufacturing method, and a liquid crystal device for a liquid crystal device, which can prevent generation and improve display quality.
[0016]
[Means for Solving the Problems]
The apparatus for manufacturing a liquid crystal device according to the present invention performs rubbing treatment by rubbing an alignment film formed on a substrate by rotating, and the rubbing tips extended from a rubbing cloth provided on a peripheral surface are rubbed. A rubbing roll inclined at a predetermined angle with respect to the rotation direction of the roll is provided.
In addition, the liquid crystal device manufacturing apparatus according to the present invention performs a rubbing process by rubbing the alignment film formed on the substrate by rotating, and the hair tip extended from the rubbing cloth provided on the peripheral surface is removed. Comprising a rubbing roll inclined at a predetermined angle with respect to the rotational direction of the rubbing roll;
The repulsive force with respect to the rotational direction in which the bristles are twisted is larger than the repulsive force with respect to the longitudinal direction of the bristles.
In addition, the liquid crystal device manufacturing apparatus according to the present invention performs a rubbing process by rubbing the alignment film formed on the substrate by rotating, and the hair tip extended from the rubbing cloth provided on the peripheral surface is removed. Comprising a rubbing roll inclined at a predetermined angle with respect to the rotational direction of the rubbing roll;
The restoring force with respect to the rotational direction in which the hair tips twist is larger than the restoring force with respect to the longitudinal direction of the hair tips.
[0017]
According to such a configuration, the hair tip is inclined at a predetermined angle with respect to the rotation direction of the rubbing roll, so that the region rubbed by one hair tip is wide, and the entire region of the liquid crystal substrate is rubbed reliably. It is possible to obtain a uniform and good orientation over the entire substrate. Moreover, it can prevent that a hair tip breaks. Further, since the restoring force in the twisting direction of the bristles is strong, even if rubbing is repeated, uneven hair density hardly occurs and a long life can be achieved.
[0018]
The bristles are inclined in a range of 2 ° to 45 ° with respect to the rotation direction of the rubbing roll.
[0019]
According to such a configuration, rubbing with reduced streak is possible. Moreover, the lifetime of a rubbing roll can be lengthened.
[0020]
Further, the hair tip is set in an inclination direction corresponding to a twist direction of the liquid crystal.
[0021]
According to such a configuration, the rubbing process can be reliably performed even on the portion having the step.
[0022]
The method of manufacturing a liquid crystal device according to the present invention is a step of rubbing an alignment film formed on a liquid crystal substrate, and rubbing a hair tip extended from a rubbing cloth provided on a peripheral surface of a rubbing roll. A rubbing process is performed by inclining at a predetermined angle with respect to the rotation direction of the roll.
[0023]
According to such a configuration, the rubbing process is performed with the hair tips inclined at a predetermined angle with respect to the rotation direction of the rubbing roll. Since the bristles are inclined, the area rubbed by one bristles is wide, and the entire area of the liquid crystal substrate can be reliably rubbed, and uniform and good alignment can be obtained over the entire area of the substrate. It is done. Moreover, it can prevent that a hair tip breaks. Further, since the restoring force in the twisting direction of the bristles is strong, even if rubbing is repeated, uneven hair density hardly occurs and a long life can be achieved.
[0024]
The bristles are inclined in a range of 2 ° to 45 ° with respect to the rotation direction of the rubbing roll.
[0025]
According to such a configuration, rubbing with reduced streak is possible. Moreover, the lifetime of a rubbing roll can be lengthened.
[0026]
The liquid crystal device according to the present invention is characterized in that it is rubbed by the liquid crystal device manufacturing apparatus or the liquid crystal device manufacturing method.
[0027]
According to such a configuration, the stripe unevenness is suppressed and the rubbing process is performed by the rubbing roll having a long life, so that the occurrence of uneven alignment and uneven tilt is prevented, and the display quality is high.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory view schematically showing a rubbing apparatus and a rubbing roll employed in the liquid crystal device manufacturing apparatus according to the first embodiment of the present invention. FIG. 2 is an equivalent circuit diagram of various elements and wirings in a plurality of pixels constituting the pixel region of the liquid crystal device. FIG. 3 is a plan view of an element substrate such as a TFT substrate as viewed from the counter substrate side together with each component formed thereon, and FIG. 4 is an assembly process in which the element substrate and the counter substrate are bonded together to enclose liquid crystal. It is sectional drawing which cut | disconnects and shows the liquid crystal device after completion | finish at the position of the HH 'line | wire of FIG. FIG. 5 is a cross-sectional view showing the liquid crystal device in detail. FIG. 6 is a flowchart showing the panel assembly process.
[0029]
In this embodiment, the direction of the bristles of the rubbing roll is inclined by a predetermined angle with respect to the direction perpendicular to the roll rotation axis.
[0030]
First, the structure of the liquid crystal panel will be described with reference to FIGS.
[0031]
As shown in FIGS. 3 and 4, the liquid crystal panel is configured by sealing a liquid crystal 50 between an element substrate 10 such as a TFT substrate and a counter substrate 20. On the element substrate 10, pixel electrodes and the like constituting pixels are arranged in a matrix. FIG. 2 shows an equivalent circuit of elements on the element substrate 10 constituting the pixel.
[0032]
As shown in FIG. 2, in the pixel region, a plurality of scanning lines 3a and a plurality of data lines 6a are wired so as to cross each other, and a pixel electrode is formed in a region partitioned by the scanning lines 3a and the data lines 6a. 9a are arranged in a matrix. A TFT 30 is provided corresponding to each intersection of the scanning line 3 a and the data line 6 a, and the pixel electrode 9 a is connected to the TFT 30.
[0033]
The TFT 30 is turned on by the ON signal of the scanning line 3a, whereby the image signal supplied to the data line 6a is supplied to the pixel electrode 9a. A voltage between the pixel electrode 9 a and the counter electrode 21 provided on the counter substrate 20 is applied to the liquid crystal 50. In addition, a storage capacitor 70 is provided in parallel with the pixel electrode 9a, and the storage capacitor 70 makes it possible to hold the voltage of the pixel electrode 9a for a time that is, for example, three orders of magnitude longer than the time when the source voltage is applied. The storage capacitor 70 improves the voltage holding characteristic and enables image display with a high contrast ratio.
[0034]
FIG. 5 is a schematic cross-sectional view of a liquid crystal panel focusing on one pixel.
[0035]
A groove 11 is formed in an element substrate 10 such as glass or quartz. A TFT 30 having an LDD structure is formed on the groove 11 with a light shielding film 12 and a first interlayer insulating film 13 interposed therebetween. The groove 11 flattens the boundary surface between the TFT substrate and the liquid crystal 50.
[0036]
The TFT 30 includes a scanning line 3a that forms a gate electrode through an insulating film 2 on a semiconductor layer in which a channel region 1a, a source region 1d, and a drain region 1e are formed. The light shielding film 12 is formed in a region corresponding to the formation region of the TFT 30, a formation region such as a data line 6a and a scanning line 3a described later, that is, a region corresponding to a non-display region of each pixel. The light shielding film 12 prevents incident light from entering the channel region 1 a, the source region 1 d, and the drain region 1 e of the TFT 30.
[0037]
A second interlayer insulating film 14 is laminated on the TFT 30, and an intermediate conductive layer 15 is formed on the second interlayer insulating film 14. On the intermediate conductive layer 15, the capacitor line 18 is disposed opposite to the dielectric film 17. The capacitance line 18 includes a capacitance layer and a light shielding layer, and forms a storage capacitor with the intermediate conductive layer 15 and has a light shielding function for preventing internal reflection of light. The intermediate conductive layer 15 is formed at a position relatively close to the semiconductor layer, so that irregular reflection of light can be efficiently prevented.
[0038]
A third interlayer insulating film 19 is disposed on the capacitor line 18, and a data line 6 a is stacked on the third interlayer insulating film 19. The data line 6a is electrically connected to the source region 1d through contact holes 24a and 24b penetrating the third and second interlayer insulating films 19 and 14. A pixel electrode 9a is stacked on the data line 6a with a fourth interlayer insulating film 25 interposed therebetween. The pixel electrode 9a is electrically connected to the drain region 1e through the capacitor line 18 through contact holes 26a and 26b that penetrate the fourth to second interlayer insulating films 25, 19, and 14. An alignment film 16 made of polyimide polymer resin is laminated on the pixel electrode 9a, and is rubbed in a predetermined direction using the rubbing roll of FIG.
[0039]
When the ON signal is supplied to the scanning line 3a (gate electrode), the channel region 1a becomes conductive, the source region 1d and the drain region 1e are connected, and the image signal supplied to the data line 6a becomes the pixel electrode. 9a.
[0040]
On the other hand, the counter substrate 20 is provided with a first light-shielding film 23 in a region facing the data line 6a, scanning line 3a, and TFT 30 formation region of the TFT array substrate, that is, in a non-display region of each pixel. The first light shielding film 23 prevents incident light from the counter substrate 20 side from entering the channel region 1 a, the source region 1 d, and the drain region 1 e of the TFT 30. A counter electrode (common electrode) 21 is formed over the entire surface of the substrate 20 on the first light shielding film 23. An alignment film 22 made of a polyimide-based polymer resin is laminated on the counter electrode 21 and rubbed in a predetermined direction.
[0041]
A liquid crystal 50 is sealed between the element substrate 10 and the counter substrate 20. Thereby, the TFT 30 writes the image signal supplied from the data line 6a to the pixel electrode 9a at a predetermined timing. Depending on the potential difference between the written pixel electrode 9a and the counter electrode 21, the orientation and order of the molecular assembly of the liquid crystal 50 change, and light is modulated to enable gradation display.
[0042]
As shown in FIGS. 3 and 4, the counter substrate 20 is provided with a light shielding film 42 as a frame for partitioning the display area. The light shielding film 42 is formed of, for example, the same or different light shielding material as the light shielding film 23.
[0043]
A sealing material 41 that encloses liquid crystal in a region outside the light shielding film 42 is formed between the element substrate 10 and the counter substrate 20. The sealing material 41 is disposed so as to substantially match the contour shape of the counter substrate 20, and fixes the element substrate 10 and the counter substrate 20 to each other. The sealing material 41 is missing in a part of one side of the element substrate 10, and a liquid crystal injection port 78 for injecting the liquid crystal 50 is formed in the gap between the bonded element substrate 10 and the counter substrate 20. The After the liquid crystal is injected from the liquid crystal injection port 78, the liquid crystal injection port 78 is sealed with a sealing material 79.
[0044]
A data line driving circuit 61 and a mounting terminal 62 are provided along one side of the element substrate 10 in a region outside the sealing material 41 of the element substrate 10, and scanning lines are provided along two sides adjacent to the one side. A drive circuit 63 is provided. On the remaining side of the element substrate 10, a plurality of wirings 64 are provided for connecting between the scanning line driving circuits 63 provided on both sides of the screen display area. In addition, a conductive material 65 for electrically connecting the element substrate 10 and the counter substrate 20 is provided in at least one corner of the counter substrate 20.
[0045]
Next, the panel assembly process will be described with reference to FIG. The element substrate 10 (TFT substrate) and the counter substrate 20 are manufactured separately. In the next steps S2 and S7, polyimide (PI) to be the alignment films 16 and 22 is applied to the TFT substrate and the counter substrate 20 prepared in steps S1 and S6, respectively. Next, in steps S3 and S8, the alignment film 16 on the surface of the element substrate 10 and the alignment film 22 on the surface of the counter substrate 20 are rubbed. This rubbing process is performed using the rubbing roll of FIG.
[0046]
Next, a cleaning process is performed in steps S4 and S9. This cleaning process is for removing dust generated by the rubbing process. When the cleaning process is completed, a sealing material 41 (see FIG. 2) is formed in step S5. Next, in step S10, the element substrate 10 and the counter substrate 20 are bonded together, and in step S11, pressure bonding is performed while alignment is performed, and the sealing material 41 is cured. Finally, in step S12, liquid crystal is sealed from a notch provided in a part of the sealing material 41, and the notch is closed to seal the liquid crystal.
[0047]
In the present embodiment, the rubbing process in steps S3 and S8 is performed by the rubbing apparatus shown in FIG.
[0048]
The rubbing apparatus shown in FIG. 1A differs from the rubbing apparatus shown in FIG. 9 in that the rubbing roll 81 shown in FIG. 1B is adopted instead of the rubbing roll 102 shown in FIG. FIG. 1 schematically shows the shape, and there is no correlation between the roll diameter and the like between FIGS. 1 (a) and 1 (b). FIG. 1A is viewed from a direction orthogonal to the stage traveling direction, and FIG. 1B is viewed from the stage traveling direction.
[0049]
In FIGS. 1A and 1B, the rubbing roll 81 is formed in a cylindrical shape and is rotatable in the circumferential direction with the center of the circle as the axis 85. On the peripheral surface of the rubbing roll 81, a rubbing cloth 82 formed of velvet-like cloth, for example, rayon, is wound. A hair tip 83 having a predetermined length extends from the surface of the rubbing cloth 82.
[0050]
In the present embodiment, as shown in FIG. 1 (b), the hair tips 83 have a predetermined angle with respect to the direction in which the level of the hair is perpendicular to the axis 85 (rotation direction of the rubbing roll 81), for example, The rubbing cloth 82 is knitted so as to be inclined by about 2 ° to 45 °. Further, the hair alignment direction of the hair tips 83 is a direction corresponding to the liquid crystal twist direction.
[0051]
Note that the rotation direction of the rubbing roll 81 and the traveling direction of the stage 100 may deviate from each other by a predetermined angle from 180 °. In this case, the combined vector of the speed vector of the rubbing roll 81 and the speed vector of the stage 100 is the rubbing direction. The inclination angle of the hair tip 83 may be set with reference to this combined vector. In the following description, for simplification of description, it is assumed that the rotational direction of the rubbing roll 81 and the traveling direction of the stage 100 are shifted by 180 ° and coincide.
[0052]
The stage 100 is configured such that the substrate 101 is placed on the upper surface. A substrate 101 (see FIG. 9) placed on the stage 100 corresponds to the element substrate 10 or the counter substrate 20 described above. The rubbing roll 81 and the stage 100 are positioned in the vertical direction so that the rubbing pressure applied to the substrate 101 by the bristles 83 of the rubbing cloth 82 becomes a predetermined value. The stage 100 is movable in a predetermined direction parallel to the surface of the substrate 101, and a rubbing roll 81 is disposed above the moving path of the stage 100, that is, the transport path of the substrate 101.
[0053]
At the time of rubbing, the rubbing roll 81 rotates so that the rubbing cloth 82 is in a direction opposite to the moving direction of the stage 100 at the portion where the rubbing cloth 82 contacts the substrate 101. The stage 100 is conveyed while rotating the rubbing roll 81 so that the entire surface of the substrate 101 is rubbed while contacting the hair tips 83 of the rubbing cloth 82 with a predetermined pressure.
[0054]
Next, the operation of the embodiment thus configured will be described with reference to FIG. FIG. 7 is an explanatory diagram for explaining a state at the time of rubbing processing with one hair tip 83 using the rubbing roll of FIG. 1.
[0055]
First, a substrate 101 (see FIG. 9) corresponding to the element substrate 10 or the counter substrate 20 on which polyimide serving as an alignment film is applied is placed on the stage 100. FIG. 7 shows an example in which an element substrate is used as the substrate 101, and shows how two adjacent pixels 91 on the element substrate are rubbed. The pixel 91 includes a pixel transistor (corresponding to the TFT 30 in FIG. 2) and a wiring portion in the peripheral portion, and a pixel electrode (corresponding to the pixel electrode 9a in FIG. 2) in the central portion.
[0056]
In this state, the stage 100 is conveyed to the rubbing roll 81 side. Further, the rubbing roll 81 is rotated. When the stage 100 reaches the vicinity of the bottom of the rubbing roll 81, the hair tips 83 of the rubbing cloth 82 come into contact with the substrate 101. Further, the bristles 83 (rubbing cloth 82) advance while rubbing the surface of the substrate 101 by rotating the rubbing roll 81 and transporting the stage 100. In this way, the entire surface of the substrate 101 is rubbed.
[0057]
In this case, as shown in FIG. 7, since the hair tips 83 are inclined at a predetermined angle with respect to the stage traveling direction, the contact length between the hair tips 83 and the substrate 101 is perpendicular to the stage traveling direction. Is long. That is, the area of the surface of the substrate 101 rubbed by one hair tip 83 by the movement of the stage 100 is extremely large. A region 94 in FIG. 7 indicates a region rubbed by one hair tip 83. As is clear from comparison between FIG. 7 and FIG. 10, the area of the surface of the substrate 101 on which each hair tip 83 is rubbed alone is extremely large. For this reason, the probability that the entire substrate is rubbed by all the hair tips 83 of the rubbing roll 81 is increased. That is, the apparent hair density can be improved, the substrate surface that is not rubbed can be reduced, and uniform and good orientation can be easily obtained over the entire substrate.
[0058]
Further, as shown in FIG. 7, each pixel 91 is formed with elements and the like in the horizontal and vertical directions with respect to the stage traveling direction. Therefore, since the hair tips 83 are inclined with respect to the stage traveling direction, even when there is a step around the pixel 91, the hair tips 83 easily come into contact with the corners of the lower steps of the steps. Therefore, the rubbing can be reliably performed even in the stepped portion, and the occurrence of alignment failure can be prevented.
[0059]
In addition, the inclination direction of the hair tips 83 is set in accordance with the twist direction of the liquid crystal, and particularly the rubbing treatment can be performed by rubbing the corners where alignment defects are likely to occur with the hair tips 83.
[0060]
In addition, since the hair tips 83 are provided at a predetermined angle with respect to the stage traveling direction, the hair tips 83 are not broken by the stage progress.
[0061]
Further, due to the contact between the hair tips 83 and the surface of the substrate 101, the hair tips 83 receive a force in the stage traveling direction and try to bend slightly in this direction. Even in this case, a part of the force received by the hair tips 83 due to the friction between the hair tips 83 and the surface of the substrate 101 becomes a force for rotating the hair tips 83 in the direction of the white arrows in FIG. The bristles 83 have a greater repulsive force in the rotational direction than a repulsive force in the longitudinal direction, and the restoring force in the rotational direction is greater than the restoring force in the longitudinal direction.
[0062]
Accordingly, when the hair tips 83 come into contact with the substrate 101 and the hair tips 83 are twisted, a stronger alignment regulating force can be applied to the alignment film due to an increase in the amount of twisting torque. Further, since the restoring force in the twisting direction of the hair tips 83 is large, even if rubbing is repeated, uneven hair density hardly occurs and the life can be extended. As a result, unevenness in the rubbing strength is less likely to occur and liquid crystal tilt unevenness can be prevented.
[0063]
As described above, in the present embodiment, since the hair tips 83 of the rubbing roll 81 are provided at a predetermined angle with respect to the stage traveling direction, the area of the surface of the substrate 101 rubbed by one hair tip 83 is reduced. By increasing the size, the apparent hair density can be improved, and a uniform and favorable orientation can be obtained over the entire substrate. In addition, the rubbing process can be reliably performed on the stepped portion, and the inclination direction of the hair tips 83 is set in accordance with the twist direction of the liquid crystal, and the rubbing process can be reliably performed on the stepped portion. . Further, the hair tips 83 are not broken by the stage progression. In addition, the alignment film can be provided with a stronger alignment regulating force, and even if rubbing is repeated, uneven hair density does not easily occur and the life can be extended, and a uniform and reliable rubbing strength can be obtained. Tilt unevenness can be prevented.
[0064]
In the above-described embodiment, an example in which a single liquid crystal substrate is placed on a stage and applied to a rubbing process has been described. However, an apparatus that performs rubbing process by placing opposing substrates on a plurality of pallets. It is clear that the present invention can also be applied. Further, although the stage 100 is moved in the horizontal direction for the rubbing process, the rubbing roll 81 side may be moved.
[0065]
Example 1
FIG. 8 shows the results of measuring the occurrence rate of stripe unevenness and the service life when the hair tips 83 are inclined with respect to the rotation direction of the rubbing roll 81 according to the first embodiment. FIG. 8 shows the measurement results of roll life with square marks, and the occurrence rate of streak irregularities with diamond marks.
[0066]
FIG. 8 shows characteristics when the inclination angle (roll winding angle) of the bristles 83 with respect to the rotation direction of the rubbing roll 81 is set to 0 ° (no inclination), 5 °, 15 °, 30 °, and 45 °. Yes. The streak occurrence rate was determined by inspecting 200 liquid crystal panels after rubbing 80 times. Further, as the lifetime, the number of times of rubbing up to the time when defects such as alignment unevenness due to a decrease in alignment regulation force occurred was used. However, the maximum number of rubs is 300.
[0067]
As shown in FIG. 8, the occurrence rate of streak defects is 2.5% lower than the case of no inclination (0 °) by setting the inclination angle of the hair tips 83 to 5 ° to 45 °. It can be seen that it can be reduced by about ~ 4.5%. As for the service life, it can be seen that when the inclination angle is set to 45 °, the usable service life is lower than in other cases. From this result, it can be seen that setting the inclination angle of the hair tips 83 to about 5 ° to 30 ° is advantageous in terms of preventing the occurrence of uneven stripes and the life.
[0068]
【The invention's effect】
As described above, according to the present invention, the hair tip is inclined with respect to the direction perpendicular to the axis of the rubbing roll, thereby increasing the area where the hair tip contacts the substrate surface and increasing the restoring force of the hair tip. In addition, by making sure that the hair tips can be contacted with respect to the stepped portion as well, it is possible to perform rubbing with a uniform and stable rubbing pressure over the entire area of the substrate, thereby preventing the occurrence of uneven alignment and liquid crystal tilt The display quality can be improved.
[Brief description of the drawings]
FIG. 1 is an explanatory view schematically showing a rubbing device and a rubbing roll employed in a liquid crystal device manufacturing apparatus according to a first embodiment of the present invention.
FIG. 2 is an equivalent circuit diagram of various elements and wirings in a plurality of pixels constituting a pixel region of the liquid crystal device.
FIG. 3 is a plan view of an element substrate such as a TFT substrate as viewed from the counter substrate side together with each component formed thereon.
4 is a cross-sectional view of the liquid crystal device after the assembly process in which liquid crystal is sealed by bonding an element substrate and a counter substrate, cut along the line HH ′ in FIG. 4;
FIG. 5 is a cross-sectional view illustrating a liquid crystal device in detail.
FIG. 6 is a flowchart showing a panel assembly process.
FIG. 7 is an explanatory diagram for explaining the operation of the first embodiment.
8 is a graph showing measurement results of Example 1. FIG.
FIG. 9 is a schematic view showing a rubbing apparatus.
FIG. 10 is an explanatory diagram viewed from the top surface of the substrate 101 in which one hair tip 104 rubs a part of the surface of the substrate 101;
FIG. 11 is an explanatory view schematically showing a state where a hair tip 104 is broken into two.
[Explanation of symbols]
81 ... rubbing roll 82 ... rubbing cloth 83 ... hair tip 100 ... stage 101 ... substrate

Claims (8)

The rubbing process is performed by rubbing the alignment film formed on the substrate by rotating, and the hair tips extending from the rubbing cloth provided on the peripheral surface are inclined at a predetermined angle with respect to the rotation direction of the rubbing roll. Equipped with a rubbing roll,
An apparatus for manufacturing a liquid crystal device, characterized in that a repulsive force with respect to a rotational direction in which the bristles are twisted is larger than a repulsive force with respect to a longitudinal direction of the bristles. The rubbing process is performed by rubbing the alignment film formed on the substrate by rotating, and the hair tips extending from the rubbing cloth provided on the peripheral surface are inclined at a predetermined angle with respect to the rotation direction of the rubbing roll. Equipped with a rubbing roll,
An apparatus for manufacturing a liquid crystal device, wherein a restoring force in a rotational direction in which the hair ends are twisted is larger than a restoring force in a longitudinal direction of the hair ends.   3. The liquid crystal device manufacturing apparatus according to claim 1, wherein the bristles are inclined in a range of 2 ° to 45 ° with respect to a rotation direction of the rubbing roll.   3. The apparatus for manufacturing a liquid crystal device according to claim 1, wherein the bristles are set in an inclination direction corresponding to a twist direction of the liquid crystal. 4. A rubbing process by rubbing an alignment film formed on a substrate, wherein a hair tip extended from a rubbing cloth provided on a peripheral surface of the rubbing roll is inclined at a predetermined angle with respect to the rotation direction of the rubbing roll. Comprising a rubbing process,
A method of manufacturing a liquid crystal device, wherein a repulsive force in a rotational direction in which the bristles are twisted is larger than a repulsive force in a longitudinal direction of the bristles. A rubbing process by rubbing an alignment film formed on a substrate, wherein a hair tip extended from a rubbing cloth provided on a peripheral surface of the rubbing roll is inclined at a predetermined angle with respect to the rotation direction of the rubbing roll. Comprising a rubbing process,
A method of manufacturing a liquid crystal device, wherein a restoring force in a rotational direction in which the hair ends are twisted is larger than a restoring force in a longitudinal direction of the hair ends.   7. The method for manufacturing a liquid crystal device according to claim 5, wherein the bristles are inclined in a range of 2 ° to 45 ° with respect to a rotation direction of the rubbing roll.   A rubbing treatment is performed by the liquid crystal device manufacturing apparatus according to any one of claims 1 to 4 or the liquid crystal device manufacturing method according to any one of claims 5 or 7. A liquid crystal device.

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