JPH05181145A - Substrate for liquid crystal element and its production - Google Patents

Abstract

PURPOSE:To obtain a substrate for the liq. crystal element having an oriented film uniform in thickness by forming an oriented film in which stamp depth controlling spacers are dispersed on a substrate main body. CONSTITUTION:A polymer film in which glass grains 10 are dispersed in a polyether ketone is formed on a substrate main body 2. The main body 2 having the polymer film is heated, and a stamper 3 is pressed on the surface to form an oriented film 1. A rugged pattern is formed on the stamper 3 surface. Since the grains 10 are densely dispersed in the oriented film 1, the protrusion 12 of the stamper 3 is abutted on the vertex of the grain 10, and the intrusion of the stamper 3 is most likely hindered. Accordingly, the thickness of the film 1 at the valley is equalized to the diameter of the grain 10. Besides, the thickness of the film 1 is controlled by changing the diameter of the grain 10 or the incliniation of the slope of the protrusion formed on the stamper 3 surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal element substrate and a method for manufacturing the same, and more particularly to a liquid crystal element substrate and a method for manufacturing the same that can form a liquid crystal element with high image quality.

[0002]

2. Description of the Related Art FIG. 4 is a sectional view showing a liquid crystal element substrate previously proposed by the present inventor. This substrate is composed of a substrate body 2 and an alignment film 1 having a thickness of several μm. The substrate body 2 includes a glass substrate 7 and a transparent electrode 8 formed thereon.
It consists of and. The alignment film 1 laminated on the substrate body 2 is made of a polymer film such as polyimide as a material, and its surface is provided with an uneven shape by a stamping method.

As a method of forming such an alignment film 1, the present inventors have studied a method of using a press device 4 as shown in FIG. The pressing device 4 is composed of a pedestal 11 and an upper plate 6. The pedestal 11 is a place on which the substrate body 2 coated with the polymer film is placed. Upper plate 6
Is to apply pressure to the polymer film by its own weight, and a stamper 3 having a predetermined uneven shape is attached to the lower surface thereof. A stopper 5 is provided around the stamper 3.

In order to manufacture a substrate using such a press device 4, first, the substrate body 2 coated with a polymer film made of polyimide or the like is placed on the pedestal 11, and then the upper plate 6 is lowered. Then, the uneven shape formed on the surface of the stamper 3 is transferred to the surface of the polymer film, and the polymer film becomes the alignment film 1. At this time, the thickness of the alignment film 1 is such that the stopper 5 abuts on the pedestal 11 so that the upper plate 6
Is determined by blocking the invasion of the polymer into the polymer film 1.

[0005]

However, when an uneven shape is formed on the surface of the polymer film by using the pressing device 4 provided with the stopper 5 as described above, the following inconvenience occurs. First, if the lower surface of the stopper 5, the upper surface of the pedestal 11, and the lower surface of the upper plate 6 to which the stamper 3 is attached are not finished with high accuracy, that is, if the accuracy of flatness and parallelism is low, the polymer film of Stamper 3 on the entire surface
Cannot be evenly contacted. In such a case, the uneven shape formed on the stamper 3 is not uniformly transferred to the surface of the polymer film, and the alignment film 1 having a non-uniform surface shape is formed, or the alignment film 1 having a non-uniform film thickness is formed. The substrate it has will be manufactured. The non-uniformity of the surface shape of the alignment film and the variation in the thickness of the alignment film 1 lead to the generation of domains, which affects the alignment of liquid crystal molecules, and adversely affects the image quality of the liquid crystal element. Further, there is a possibility that unevenness may occur due to an insulating place between the liquid crystal layer and the transparent electrode 8. In order to prevent such a problem, the accuracy of the flatness and parallelism may be increased. However, in reality, the film thickness of several μm required for the alignment film 1 and the stamper on the surface thereof are uniform. It is impossible to transfer the above shape and further increase the flatness and parallelism of the pressing device 4 to the extent that the uniformity of the film thickness can be achieved.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a substrate for a liquid crystal element in which an alignment film 1 having a uniform surface shape and a uniform film thickness can be easily manufactured, and a manufacturing method thereof. And

[0007]

In the liquid crystal device substrate according to the first aspect, the above problem is solved by forming an alignment film in which a stamp depth regulating spacer is dispersed on the substrate body.

A method for producing a liquid crystal element according to a second aspect is a method for producing a substrate for a liquid crystal element according to the first aspect,
First, a film in which the stamp depth control spacers are dispersed is laminated on the substrate body, and then a stamper having an uneven shape is pressed against the film until the stamper prevents the stamper from entering the film. I tried to solve it.

The shape of the spacer is not particularly limited, but a spherical shape whose height does not change regardless of the arrangement is preferable. The particle size of the spacer is related to the film thickness of the film in which the spacer is dispersed and the depth of the irregularities formed on the surface, and the particle size is preferably 80 to 1500 angstroms. If the particle size of the spacer is smaller than 80 angstrom, it is difficult to control the film thickness on the inner surface of the substrate, and the uneven shape formed on the surface of the film becomes unstable. Spacer particle size is 1
When it exceeds 500 angstroms, the film thickness becomes equal to or more than that, the light transmittance decreases, and the display contrast of the liquid crystal element decreases, or the film capacity increases and the voltage effectively acting for display decreases. .. As a material for the spacer, a material having a small coefficient of thermal expansion so that the height does not change due to heating is suitable because the spacer itself is also heated when the uneven shape is formed on the surface of the alignment film. Further, in the case of forming a concavo-convex shape on the surface of the alignment film by using a stamper having a concavo-convex shape on the surface and having a flat overall shape, the spacer should be 100
It is desirable to distribute at a density of about 1000 pieces / mm ² .

When the uneven shape is formed on the surface of the alignment film by using a stamper having the uneven shape on the surface and the entire shape is curved, the spacer distribution density is set to 10
It is desirable to set it to about 0 to 3000 pieces / mm ² . When using a stamper whose overall shape is flat, the pressure is dispersed when the stamper is brought into contact with the spacer, so the density is relatively low (100 to 1000 pieces / mm ² ).
The stampers to be pressed can be supported by the spacers dispersed in the. On the other hand, when using a stamper with a curved overall shape, the pressure is not dispersed when the stamper is brought into contact with the spacer, so the density is relatively high (about 100 to 3000 pieces / mm ² ) so as to withstand the pressure. It is necessary to disperse spacers in the alignment film.

[0011]

In the liquid crystal device substrate according to the first aspect of the present invention, the alignment film in which the stamp depth regulating spacers are dispersed is formed on the substrate body. Therefore, when the stamper is pressed against the film to manufacture the alignment film. The spacers prevent the stamper from entering, and the stamper does not approach the substrate body any more. Since the spacers are dispersed throughout the alignment film, the surface shape of the alignment film is uniform and the film thickness is uniform.

According to a second aspect of the present invention, there is provided a method of producing the liquid crystal element substrate according to the first aspect, wherein a film in which the stamp depth regulating spacers are dispersed is first laminated on the substrate main body, and then the film is formed. Since the stamper having the uneven shape is pressed against the film until the spacer prevents the stamper from entering, the spacer prevents the stamper from entering at a predetermined position, and the stamper does not approach the substrate body beyond that position. .. As a result, an alignment film having a uniform surface shape and a uniform film thickness can be formed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal element substrate and a method for manufacturing the same according to the present invention will be described in detail below with reference to the drawings. The same components as those of the conventional example are designated by the same reference numerals to simplify the description.

(Embodiment 1) FIG. 1 is a cross-sectional view showing a liquid crystal element substrate of this embodiment. This liquid crystal element substrate is composed of a substrate body 2 and an alignment film 1. The substrate body 2 has a transparent electrode 8 made of ITO formed on a glass substrate 7. The alignment film 1 is made of polyetherketone (P
ES) is a film in which glass particles 10 are dispersed,
It is formed on the substrate body 2. The glass particles 10 in the alignment film 1 have a diameter of 700 Å, and the alignment film 1 has a thickness of 800 Å. The glass particles 10 are dispersed in the alignment film 1 at about 500 particles / mm ² .

The liquid crystal element substrate was manufactured by the following steps. In advance, 1-methyl-2-pyrrolidone was used as a solvent, and glass particles 10 and PES were added to the solvent to prepare a mixed solution. The mixed solution was printed in a predetermined shape on the substrate body 2. The solvent was evaporated by drying the mixed solution to form a polymer film. The thickness of this polymer film is 800
It was Angstrom. The substrate body 2 having the polymer film is heated to 200 to 240 ° C., and the stamper 3 is attached to the surface of the substrate body 2 as shown in FIG.
It was pressed at a pressure of 00 kg / cm ² . The stamper 3 has a pitch of 2800 angstroms and a depth of 10 on the surface.
An uneven pattern of 0 angstrom was formed. In the liquid crystal element substrate of this example, the glass particles 10 are dispersed in the alignment film 1 at a high density (about 500 particles / mm ² ).
It is highly probable that the stamper 3 will be blocked by the apex of 0. Therefore, this alignment film 1 has the same film thickness at the valley as the particle size of the glass particles 10.

In the liquid crystal device substrate of this embodiment, the alignment film 1 in which the glass particles 10 are dispersed is formed on the substrate main body 2. Therefore, in order to manufacture the alignment film 1, the stamper 3 is pressed against the film. At this time, the glass particles 10 prevent the stamper 3 from entering, and the stamper 3 does not approach the substrate body 2 any more. Glass particles 10
Are dispersed throughout the alignment film 1, so that the film thickness of the alignment film 1 is uniform. Therefore, the liquid crystal element substrate of this example was a liquid crystal element substrate provided with the alignment film 1 having a uniform film thickness.

In the manufacturing method of this embodiment, first, the film in which the glass particles 10 are dispersed is laminated on the substrate body 2, and then the stamper 3 having the uneven shape is introduced into the stamper 3 by the glass particles 10. The glass particles 10 prevent the stamper 3 from entering at a predetermined position, and the stamper 3 does not approach the substrate body 2 beyond that position. as a result,
The alignment film 1 having a uniform film thickness can be formed. Therefore, according to the manufacturing method of this embodiment, the alignment film 1 having a uniform thickness is formed.
It is possible to manufacture a liquid crystal element substrate having

(Embodiment 2) FIG. 3 is a sectional view showing a liquid crystal element substrate of this embodiment. Glass particles 10 are dispersed at a low density (about 100 particles / mm ² ) in the alignment film 1 of the liquid crystal element substrate. In this way, when the glass particles 10 are dispersed at a relatively low density, when the protrusions 12 of the stamper 3 come into contact with the glass particles 10, the glass particles 10 move along the inclined side surface as the stamper 3 enters. It is moved into the recess of the stamper 3.

In the liquid crystal element substrate of this embodiment, the glass particles 10 are contacted with the inclined side surfaces of the stamper 3 to prevent the stamper 3 from entering the polymer film. As a result, in the liquid crystal element substrate of this example, the glass particles 1
0 enters the convex portion formed on the surface of the alignment film 1 and is in contact with the inclined side surface of the alignment film 1. Therefore, also in the liquid crystal element substrate of this embodiment, the same operational effect as in Embodiment 1 can be obtained.

Further, in the liquid crystal element substrate of this embodiment, the film thickness of the alignment film 1 can be changed by changing the particle diameter of the glass particles 10 or the inclination angle of the slope of the convex portion formed on the surface of the stamper 3. You can control.

[0021]

The substrate for a liquid crystal device according to claim 1 has an alignment film, in which spacers for controlling stamp depth are dispersed, formed on the substrate body. Therefore, a stamper film is formed to manufacture this alignment film. When pressed against, the spacer prevents the stamper from entering, and the stamper does not approach the substrate body any more. Since the spacers are dispersed throughout the alignment film, the surface shape of the alignment film is uniform and the film thickness is also uniform. Therefore, the liquid crystal element substrate according to claim 1 is a liquid crystal element substrate provided with an alignment film having a uniform surface shape and a uniform film thickness.

According to a second aspect of the present invention, there is provided a method of producing the liquid crystal element substrate according to the first aspect, wherein a film having a stamp depth regulating spacer dispersed therein is first laminated on the substrate body, Next, since the stamper having the uneven shape is pressed against the film until the stamper prevents the stamper from entering, the spacer prevents the stamper from entering at a predetermined position, and the stamper does not approach the substrate beyond that position. .. As a result, an alignment film having a uniform surface shape and a uniform film thickness can be formed. Therefore, according to the manufacturing method of the second aspect, it is possible to manufacture a liquid crystal element substrate provided with an alignment film having a uniform surface shape and a uniform film thickness.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a liquid crystal element substrate of Example 1.

FIG. 2 is a schematic cross-sectional view for explaining a process of manufacturing an alignment film of a liquid crystal element substrate of Example 1.

FIG. 3 is a schematic cross-sectional view showing a liquid crystal element substrate of Example 2.

FIG. 4 is a schematic cross-sectional view showing a conventional liquid crystal element substrate.

FIG. 5 is a schematic cross-sectional view for explaining a process of manufacturing an alignment film of a conventional liquid crystal element substrate.

[Explanation of symbols]

 1 Alignment film 2 Substrate body 3 Stamper 10 Spacer (glass particles)

Claims (2)

[Claims] 1. A substrate for a liquid crystal element, wherein an alignment film in which a stamp depth regulating spacer is dispersed is formed on a substrate body. 2. The method for manufacturing a substrate for liquid crystal device according to claim 1, wherein a film in which a stamp depth regulating spacer is dispersed is first laminated on a substrate body, and then an uneven shape is formed. A method for manufacturing a substrate for a liquid crystal device, characterized in that a stamper present is pressed against the film until the spacer prevents entry.