JPH02130529A - Liquid crystal display element and production thereof - Google Patents

Abstract

PURPOSE:To increase the degree of freedom of fixed display patterns and to easily produce even the large-sized patterns and intricate patterns with good productivity by using oriented films which are subjected to partially different orientation treatments in the fixed display parts and sealing material in the display area provided to the region inner than a peripheral seal, thereby forming the patterns. CONSTITUTION:An over coating layer for the oriented film consisting of 50nm polyimide is formed on a glass substrate 1 and a metal mask having aperture in the parts desired to make fixed display is disposed thereon. Post parts 4A, 4B of this metal mask are disposed afterward with the sealing materials in the display region. The sealing material 2 consisting of an epoxy resin is printed on the part of the periphery of the substrate 1 and the inside of the display area and spacers are sprayed. Two sheets of such substrates 1 are disposed and press welded in such a manner that the oriented film surfaces face each other to form an empty cell. The post parts of the sealing material in the display area which remains as the mask rubbing is not possible are used as the fixed display parts 4A, 4B. The continuous fixed display patterns having the high degree of freedom are obtd. by the mask rubbing and the sealing material in the display area in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal display element having a fixed display portion therein.

[Prior art] A liquid crystal display element is made by sealing a substrate that has been subjected to alignment treatment with a sealing material, injecting liquid crystal into the interior of the substrate and sealing it, and placing polarizing plates on both sides of the substrate. It is manufactured by external printing on the top or cell, and by connecting a pin or flexible connector to the terminal outlet.

The display pattern of such a liquid crystal display element is usually formed by applying a voltage to a desired electrode, but in recent years bright or dark fixed display patterns have been required due to the diversity of displays. Such a fixed display pattern is configured within or outside the liquid crystal cell.

When configuring a fixed display pattern within a liquid crystal cell, there are basically three methods: displaying it by partially changing the alignment process, transmitting light with a sealant, blocking light with a light-shielding film, and so on. There are methods that combine the two.

When configuring a fixed display pattern outside the liquid crystal cell, methods include external printing on the substrate or polarizing plate, placing a filter with a specific display pattern externally, and using polarizing plates with partially different polarizing functions. There is.

These fixed display pattern displays can be compatible with liquid crystal display elements of negative type display or positive type display. Among these, negative type liquid crystal display elements, which have recently been attracting particular attention as a system capable of producing beautiful displays, require fixed display in a state where light is transmitted.

For this purpose, a fixed display method that uses light shielding cannot be used, so a fixed display method that allows light to pass through is required. A typical method for this is to align the alignment film by rubbing in a certain direction, then place a mask with a specific shape on top of it, and then apply the alignment process by rubbing in a direction different from the previous rubbing direction. The rubbing method is often used.

[Problems to be Solved by the Invention] However, in recent years, large and complex fixed display patterns have been required for negative type displays, and the mask rubbing method has reached its limit.

In the mask rubbing method, after applying normal rubbing,
A fixed display is formed by using a metal mask with an opening in the area where the fixed display is desired, and rubbing in a different direction from the previous one.

If this metal mask is thick, it will be difficult to apply rubbing, and the orientation of the boundary between the fixed display portion and other portions will be disturbed, resulting in poor visibility. For this reason, it is necessary to make the metal mask as thin as possible.However, if the metal mask is made too thin, it is likely to roll up or warp during the rubbing process.
Therefore, it is becoming difficult to perform uniform alignment treatment.

Additionally, when the fixed display pattern becomes larger or more complex, it also has the problem that it tends to peel up or warp during rubbing, resulting in poorly aligned areas, similar to when a metal mask is made thinner. Ta. For this reason, efforts are being made to improve this by inserting pillars into the metal mask openings. However, even this is not perfect (and the pillars restrict the design of the fixed display section and worsen visibility), which poses a major problem in display pattern design. Forming a large and complicated fixed display pattern by mask rubbing greatly reduces the yield and impairs productivity.

In addition, instead of this mask rubbing method, a method has been proposed in which the portion where a fixed display pattern is to be formed is vertically aligned to eliminate the optical rotation of the liquid crystal, but this method also does not allow for uniform alignment in large areas or complex patterns. It was difficult to obtain, and there remained problems in terms of reliability.

Furthermore, a method is also known in which the fixed display pattern is formed using an in-display area seal material provided in an area inside the peripheral seal.

With this method of fixed display using sealing material, it is relatively easy to create circular or short linear patterns like the colons between hours and minutes on a clock. However, large fixed display patterns such as long straight lines have problems such as poor linearity of the sticker (low visibility and poor appearance), and the time it takes to inject the liquid crystal. Ta.

It was also considered to provide electrodes in all the fixed display areas and drive them by applying voltage to the electrodes, but this resulted in limitations in the design of the fixed display pattern and required complex fine patterning and double-layer wiring. This has the problem of lowering productivity. Furthermore, this method also had the disadvantage of increasing power consumption and eliminating the advantage of low power consumption of liquid crystal display elements.

Means for Solving Problem E] The present invention has been made to solve the above-mentioned problems, and includes forming an alignment film on a pair of substrates provided with electrodes, and making the surfaces of the alignment films face each other. In a liquid crystal display element whose periphery is sealed with a sealant and liquid crystal is sealed inside, the fixed display is partially treated with an alignment film that has undergone different alignment treatments, and within the display area provided in the area inside the peripheral seal. A liquid crystal display element characterized by the use of a sealing material, and an alignment film is formed on a pair of substrates provided with electrodes, an alignment treatment is performed by rubbing, the surfaces of the alignment film are made to face each other, and the periphery is sealed with a sealant. In a method of manufacturing a liquid crystal display element in which a liquid crystal is sealed inside, the alignment film of at least one substrate is aligned by rubbing in a certain direction, and then a mask of a specific shape is placed on top of the alignment film, and the previous rubbing is performed. Provided is a method for manufacturing a liquid crystal display element, characterized in that alignment treatment is performed by rubbing in a direction different from the direction, and a sealing material within the display area is placed in an area inside the peripheral seal to perform fixed display. It is.

In the present invention, fixed display is performed using an alignment film partially subjected to different alignment treatments and an in-display area sealing material provided in an area inside the peripheral seal. In particular, as the alignment film partially subjected to different alignment treatments, an alignment film subjected to horizontal alignment treatment by rubbing in different directions is used.

This makes it possible to manufacture liquid crystal display elements having large areas and complicated fixed display patterns with high productivity.

The present invention will be explained with reference to the drawings.

FIG. 1 is a front view showing an example of a substrate of a liquid crystal display element of the present invention.

In Fig. 1, 1 is a substrate, 2 is a peripheral sealing material that seals its periphery, 3A, 3B, and 3C are fixed display parts that have been subjected to different alignment treatments such as mask rubbing, and 4A and 4B are within the display area. This is a fixed display part made of a sealing material, 5A, 5B, and 5C are display patterns made of electrodes, 6 is an injection port, and 7 is a sealing material for the injection port.

That is, in this example, both the fixed display portions 3A, 3B, and 3C formed by different orientation processes and the fixed display portions 4A and 4B formed by the sealing material within the display area become fixed display portions.

The fixed display portions with different alignment treatments only need to have different alignment treatments, such as vertical alignment (including a slightly inclined vertical alignment) and horizontal alignment (including a slightly inclined horizontal alignment). A combination of different horizontal orientations can be used.

In the former case, the entire structure can be horizontally aligned, then a mask having openings is placed only in specific parts, and the vertical alignment material is applied only to those parts. The other parts were rubbed in directions that were 90 degrees apart from each other using two substrates, and a pair of polarizing plates was placed above and below so that their polarization axes were parallel to each other. The parts appear black when no voltage is applied;
It appears white when a voltage is applied, and a desired pattern can be displayed depending on the voltage application state. Since light always passes through the vertically oriented parts, the display becomes fixed.
It will appear white.

In the latter case, after horizontally aligning the whole in a specific direction,
It is sufficient to arrange a mask having openings only in a specific part, and to orient that part in a direction different from the previous one. This 2
The orientation treatment direction of each type is usually shifted by 90 degrees, but depending on the requirements of the viewing angle, drive margin, etc., it may be shifted from 90 degrees and set to another angle, for example, 70 degrees.

As for these horizontal alignment processing methods, any method that has been conventionally used as a horizontal alignment processing method can be used.
The rubbing method is most suitable. Of course, a horizontal alignment treatment method such as an oblique vapor deposition method can also be used.

In particular, the present invention uses a mask rubbing method in which, after the entire surface is horizontally aligned in a specific direction using a rubbing method, a mask having an opening is placed only in a specific portion, and that portion is rubbed and aligned in a different direction from the previous one. It is preferable to use This results in high productivity and can be applied without major changes to conventional processes.

Specifically, in the substrate 1 in FIG. 1, only the normal portion is rubbed at an angle of 45° from the upper left to the lower right, and openings are formed only in the fixed display portions 3A, 3B, and 3C due to different orientation treatments. All you have to do is place the mask and rub at a 45° angle from the bottom left to the top right. In this case, the mask is connected by a support at a portion corresponding to 4A and 4B.

The other board only needs to be rubbed at an angle of 45° from the bottom left to the top right, resulting in 3A and 3B.
, 3C, the alignment directions of the upper and lower substrates are parallel, and light does not rotate in the liquid crystal layer.

Between the alignment film that performs normal display and the alignment film that faces it, the intersection angle of the alignment processing direction between both substrates is usually 90°, but this intersection angle of the alignment processing direction is 70°.
The angle may be about 110°. On the other hand, between the alignment film in the portion corresponding to the fixed display pattern and the opposing alignment film formed by different alignment processes, the alignment process direction between both substrates is usually set to approximately Oo.
The angle may be about 0 to -20°.

Furthermore, in the present invention, 4A and 4B, which correspond to the pillars of the mask,
A sealing material is placed in the area, so the light does not rotate.

This sealing material may be the same sealing material as the sealing material used for the peripheral seal, and can be printed at the same time as printing of the peripheral seal, so productivity will not be reduced. Of course, printing may be performed using different sealing materials by changing the process.

In addition, the fixed display pattern created by the sealing material within the display area is less likely to be inaccurate if it is not too large, and
This is preferable since it may adversely affect the injection of liquid crystal. In particular, when forming a somewhat long straight line, it is preferable that the direction is parallel to the direction in which the liquid crystal is injected.

Furthermore, it is preferable that the fixed display pattern formed by the sealing material within the display area slightly overlap with the fixed display pattern formed by a different orientation process, since pattern defects due to positional deviations are less likely to occur.

A pair of substrates provided with electrodes used in the present invention include I
A substrate made of glass, plastic, or the like provided with a transparent conductive film such as T O (InlO8-Sn02) % Snow can be used. This transparent conductive film may be used in combination with a lead made of low resistance chromium, titanium, aluminum, or the like. The surface of this substrate is made of resin such as polyimide or polyamide, or 5iO1A.
An alignment film of an inorganic material such as 1□03 is formed, and an alignment treatment such as rubbing is performed. Of course, in addition to this, TiO□, S
An insulating film made of an inorganic material such as io2 or AltOm, a light shielding film, a color filter, etc. may be provided. The orientation of this alignment film is partially changed to obtain a fixed display by different alignment treatments.

A sealing material is printed around the periphery and within the display area of such a substrate, and the alignment film surfaces are opposed to each other and pressed together to harden the seal. Next, liquid crystal is injected through the injection port, and the injection port is sealed to complete the cell. Note that liquid crystal may also be injected at the time of sealing to form a cell without an injection port.

A pair of polarizing plates is usually arranged on both sides of this liquid crystal cell, and the polarization axes of these plates are almost perpendicular in the case of a normal positive type liquid crystal display element, and in the case of a negative type liquid crystal display element. are made almost parallel.

Since a fixed display as in the present invention is suitable for a negative type liquid crystal display element, it is preferable that the polarization axes are parallel.

FIG. 2 shows a front view of an example of a substrate of a liquid crystal display element having another fixed display portion.

That is, the fixed display portions 13A, 1 due to different orientation treatments
3B, 13G, 130.132.13F, 13G,
13H, 13I, 13J.

13, 13L and fixed display portions 14A, 14B, 14G% 140.14E with sealing material within the display area,
14F, 14G, 14H, 14I, 14J, 14
14L is provided in the. Among these, fixed display parts 14A, 140.14G, 1 with sealing material within the display area
4J has long sides that are almost parallel to the direction of liquid crystal injection from the injection port.

In addition, a color filter layer may be formed on the inner or outer surface of the substrate, a polarizing film substrate may be used as the substrate, a touch switch, an ultraviolet cut filter, or a non-reflection filter may be laminated on the outer surface of the substrate. The technique applied to ordinary liquid crystal display elements may be applied within a range that does not impair the effects of the invention.

[Function] In the present invention, it is possible to easily obtain a fixed display with a large size or a complicated shape that cannot be manufactured with a high yield by the mask rubbing method, etc., and it can be manufactured with a high yield and productivity similar to conventional liquid crystal display elements. be able to.

[Example] Example 1 As shown in Fig. 1, ITo of a glass substrate with ITo was patterned by photoetching, a 50 nm overcoat layer for an alignment film of polyimide was formed thereon, and the entire structure was patterned. Rub in a 45° diagonal direction, then place a metal mask with an opening in the part you want to display fixedly.
Rubbing was performed in a direction shifted by 90° from the previous rubbing direction. At this time, a support was provided at the opening of the metal mask to prevent the metal mask from bending or bending. Since the support portions of this metal mask will not undergo any new alignment treatment, a sealing material within the display area will be placed later. The other substrate was rubbed in a direction in which the alignment film was shifted by 90° from the rubbing direction of the substrate, and in a direction opposite to that of the fixed display portion of the substrate.

Next, a sealing material made of epoxy resin was printed on the periphery and in the display area, spacers were scattered, and the two substrates were arranged and pressure-bonded so that the alignment film surfaces faced each other to form empty cells.

With this display area sealing material, the remaining column portions that could not be mask rubbed are used as fixed display portions. This results in
A continuous fixed display pattern can be obtained by mask rubbing and sealing material within the display area.

Next, nematic liquid crystal was injected through the injection port, and the injection port was sealed to produce a liquid crystal cell. A liquid crystal display element in which a pair of polarizing plates is arranged on both sides of the liquid crystal cell so that the polarizing axes of the plates are perpendicular to the orientation direction of adjacent liquid crystal molecules (so that the polarizing axes are orthogonal to each other) is as follows: It was a positive type display, with a black fixed display part on a white background and a black display part whose display changed when driven.

As a result, the fixed display part was a combination of the fixed display part by mask rubbing and the fixed display part by the sealing material in the display area, and it had good visibility with no pattern shift (no discomfort). There was no occurrence of more than orientation due to deformation of the metal mask during mask rubbing, and there was almost no decrease in productivity such as a long liquid crystal injection time.

Example 2 The same liquid crystal cell as that of Example 1 was used, and a pair of polarizing plates were placed on both sides of the liquid crystal cell, with one substrate having its polarization axis perpendicular to the alignment direction of adjacent liquid crystal molecules, and the other substrate having a polarizing axis perpendicular to the alignment direction of adjacent liquid crystal molecules. The substrate was arranged so that its polarization axis was parallel to the alignment direction of adjacent liquid crystal molecules (the polarization axes were parallel to each other).

This liquid crystal display element had a negative type display, and had a fixed white display part on a black background and a white display part whose display changed when driven.

As a result, the fixed display part is a combination of the fixed display part by mask rubbing and the fixed display part by sealing material in the display area, so there is no pattern shift, color unevenness that is noticeable with negative type is not noticeable, and there is no discomfort. It had good visibility. In addition, there was no occurrence of more than orientation due to deformation of the metal mask during mask rubbing, and there was almost no decrease in productivity such as a long liquid crystal injection time.

[Effects of the Invention] In the present invention, the fixed display is performed using an alignment film partially subjected to different alignment treatments and a display area sealing material provided in an area inside the peripheral seal. It has a high degree of freedom and can easily manufacture large fixed display patterns and complex fixed display patterns, which have been difficult in the past, with good productivity.

Furthermore, by using a mask rubbing method for different alignment treatments, it is possible to manufacture with high productivity without significantly changing the conventional production process.

Furthermore, by providing a sealing material within the display area in a part of the display area, it is possible to prevent the mask from bending due to mask rubbing, etc., to form an accurate pattern, and to improve control of the gap between the substrates of the liquid crystal cell. Furthermore, since the sealing material within the display area does not have to be provided in a long pattern, there are no drawbacks such as the liquid crystal injection time being significantly lengthened or bubbles remaining.

In addition to this, the present invention can be applied in various other ways as long as the effects of the present invention are not impaired.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of a substrate of a liquid crystal display element of the present invention. FIG. 2 is a front view showing an example of a substrate of another liquid crystal display element of the present invention. 1 is the substrate, 2 is the peripheral sealing material, 3A, 3B, 3c, L3
A-13L is a fixed display part with different orientation processing, 4
A, 4B, 14A-141 are fixed display parts with sealing material in the display area, 5A, 5B, 5G are display patterns, 6
is the injection port, 7 is the sealing material Figure 1 Figure 3 Figure 4 Figure 2 Figure 5 Procedure amendment (travel) March 14, 1999

Claims (2)

[Claims] (1) In a liquid crystal display element in which an alignment film is formed on a pair of substrates provided with electrodes, the surfaces of the alignment films are opposed to each other, the periphery is sealed with a sealant, and liquid crystal is sealed inside, the fixed display is partially removed. 1. A liquid crystal display element characterized by using an alignment film that has been subjected to different alignment treatments and a display area sealant provided in an area inside a peripheral seal. (2) A liquid crystal display element in which an alignment film is formed on a pair of substrates provided with electrodes, an alignment treatment is performed by rubbing, the surfaces of the alignment films are faced to each other, the periphery is sealed with a sealant, and liquid crystal is sealed inside. In the manufacturing method, the alignment film of at least one substrate is aligned by rubbing in a certain direction, and then a mask of a specific shape is placed on top of the alignment film, and the alignment process is carried out by rubbing in a direction different from the previous rubbing direction. Also, a method of manufacturing a liquid crystal display element, characterized in that a sealing material within a display area is arranged in a region inside the peripheral seal to perform a fixed display.