JPS60163021A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To form easily a large-sized display, and to obtain a display whose appearance quality is uniform even if an external light reflection exists, by constituting the titled element so that only an orienting direction corresponding to an unchangeable display of an oriented film of one electrode substrate of a TN type liquid crystal display element of a field effect type is made different partially from other part. CONSTITUTION:With regard to orienting directions 14, 24 and 25 of oriented films 12, 22 on one electrode substrate of upper and lower electrode substrates 11, 21 of a TN type liquid crystal display element of a field effect type having always an unchangeable display in addition to a display which appears by impressing a voltage, only a part 26 corresponding to the unchangeable display is made different partially from other part 27 of its electrode substrate 21. Therefore, when impressing no voltage, a liquid crystal 31 of the unchangeable display corresponding part 26 executes a homogeneous orientation, a liquid crystal 32 of other part 27 executes a twist orientation, a cell in which both the orientations exist together is obtained, and a homogeneous orienting area becomes a display area which always remains unchanged irrespective of whether a voltage is impressed or not. Also, both positive and negative displays can be executed. Also, it is possible to eliminate uniformity of a reflection factor generated by a difference of a liquid crystal refractive index of a boundary part to which a different oriented state in the vicinity of the unchangeable display part contacts, and a display whose appearance quality is good is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a liquid crystal display element, and particularly to a twisted nematic type (hereinafter referred to as TN type) liquid crystal display element suitable for a case where a relatively large unchanging display exists.

[Background of the invention]

In conventional TN type liquid crystal display elements, in order to orient the liquid crystal molecules to form a spiral structure between the two upper and lower electrode substrates, the surface of the electrode substrate in contact with the liquid crystal is treated with one-sided treatment, such as with cloth. A so-called rubbing method, in which the material is rubbed in one direction, is generally used. The two electrode substrates that have been oriented in this way are placed opposite each other so that their respective rubbing directions, that is, the alignment directions, intersect, for example, at 90 degrees, and the periphery is adhered with a sealing material, and a liquid crystal, for example, a positive dielectric, is placed inside. When filled with anisotropic nematic liquid crystal,
The liquid crystal molecules are arranged in a spiral structure between the upper and lower electrode substrates.

A liquid crystal display element is constructed by bonding polarizing plates to the outside of each of the upper and lower electrode substrates of the liquid crystal cell thus constructed.

By the way, in a conventional TN type liquid crystal display element having such a configuration, in order to form a pattern that is always displayed unchanged regardless of voltage application, it is necessary to form the pattern with a sealant at the corresponding location of the cell. Part PF
A structure is adopted in which no liquid crystal is present.

However, with this structure, if the permanent display is an Arabic numeral zero, liquid crystal cannot be injected into the inside of the zero surrounded by the sealing material after the cell is completed, so the liquid crystal cannot be injected into the interior of the zero surrounded by sealing material after the cell is completed. This has the drawback that the liquid crystal material will adhere to the sealing material, and there is a risk that the seal will peel off under conditions such as high temperature and high humidity.

[Purpose of the invention]

An object of the present invention is to provide a liquid crystal display element that does not have the above-mentioned drawbacks, can easily form a relatively large unchanging display using simple means, and has a display with uniform appearance quality even when external light is reflected. It is about providing.

[Summary of the invention]

In order to achieve the above object, the present invention provides a field effect TN type liquid crystal display element which has an always constant display in addition to the display that appears when a voltage is applied. The present invention is characterized in that the orientation direction of the alignment film on one electrode substrate is partially made different from the other portions of the electrode substrate only in a portion corresponding to the unchangeable display portion.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. 1 is an upper surface substrate, 2 is a lower surface substrate, 11 is an upper electrode substrate, 21 is a lower electrode substrate, 12.22 is an alignment film, 13
．． 23 is a polarizing plate, and 3 is a liquid crystal.

First, as shown in FIG. 1, an upper substrate 1 and a lower substrate 2 are prepared. Here, the alignment direction 14 of the alignment film 12 of the upper substrate 1 is applied to the entire surface in one direction shown by the arrow. The alignment direction 24 of the alignment film 22 of the lower substrate 2 is perpendicular to the alignment direction 14 over the entire surface.

Specifically, the orientation direction indicates, for example, a rubbing direction or a vapor deposition direction.

Next, as shown in FIG.
Make it different. For example, the orientation direction 2 of the unchanged display corresponding portion 26
5 rubs in the same direction ζ as the alignment direction 14 of the alignment film 12 on the upper substrate 1. In order to provide two alignment directions 24 and 25 on the alignment film 22 of the lower substrate 2, after processing the alignment film 22 in the alignment direction 24 as shown in FIG. Only the corresponding portion 26 may be exposed and rubbing or vapor deposition may be performed.

Next, the peripheries of the upper substrate 1 and the lower substrate 2 are sealed with a sealing material (not shown), and a nematic liquid crystal 3 having positive dielectric anisotropy is sealed inside as shown in FIG.

As a result, when no voltage is applied, the unchanged display corresponding portion 26
The liquid crystal 31 at 27 becomes a homogeneous alignment region, and the liquid crystal 32 at other places 27 becomes a twisted alignment region, resulting in a cell in which both regions coexist. The homogeneous alignment region is a region that always displays an unchanged display regardless of whether or not a voltage is applied. Furthermore, if the polarization axes of the upper and lower polarizers 13 and 23 are orthogonal to each other, a positive display (the display area is dark) can be obtained, and if they are parallel to each other, a negative display (the display area is white) can be obtained. Further, when a constant color display is used together with color printing or a color filter, a constant color display can be obtained.

Furthermore, the alignment direction 24 of the alignment film 22 on the inner surface of the lower electrode substrate 21
．． 25 in a direction that is partially different from that of the other parts 27 in the unchanged display corresponding part 26, the alignment film 1 of the upper electrode substrate 11 is
When processing 2, it is possible to eliminate the uniformity of the reflectance caused by the difference in the refractive index of the liquid crystal at the boundary where different orientation states near the support part touch, and a display with good appearance quality can be obtained. .

In the above embodiment, the orientation direction of the alignment film 22 of the lower electrode substrate 21 was changed only in the unchanged display corresponding portion 26 from the other region 27; Even if the orientation direction of the alignment film 12 of the upper electrode substrate 11 is changed only in the portion corresponding to unchangeable display from that elsewhere, the effect of always displaying an unchangeable pattern can be obtained.

[Effects of the Invention] As is clear from the above explanation, according to the present invention, constant display can be achieved with only a slight increase in the number of processing steps for the alignment film, as well as positive display. Negative display can also be easily displayed, and a display with uniform appearance quality can be obtained even when external light is reflected.

[Brief explanation of drawings]

1 and 2 are process explanatory diagrams showing the 6- manufacturing process of the liquid crystal display element according to the present invention, and FIG. 3 is an explanatory diagram showing an embodiment of the liquid crystal display element according to the present invention in a state in which no voltage is applied. It is. 11... Upper electrode substrate, 21... Lower electrode substrate, 12
．． 22... Alignment film, 14.24.25... Orientation direction, 26... Location corresponding to unchangeable display, 27... Other location. 7- Figure 1 Figure 2 Figure 3 1') Q-

Claims (1)

[Claims] In addition to the display that appears when a voltage is applied, the direction of alignment of the alignment film on either the lower electrode substrate or the upper electrode substrate in a field-effect twisted nematic liquid crystal display element that has a constant display. A liquid crystal display element characterized in that only a portion corresponding to the unchanging display is partially different from other portions of the electrode substrate.