JPH01140125A - Indicating body - Google Patents

Abstract

PURPOSE:To enable formation of an indicating body on not only a plane but also a curved surface and to enable cutting of the indicating body by constituting an indicating part of the indicating body of a membrane consisting of a dielectric as a medium, and separating an electro-optical material contained in the dielectric to minute regions. CONSTITUTION:A material 2 contg. electro-optical effect as an essential component separated to minute regions, and a ferroelectric material 3 are distributed with an optional density in a dielectric 4 constituting a medium in a region interposed between electrodes 1. Said electrodes comprise transparent SnO2, ZnO, etc. If the indicating body is a reflection type one, one of the electrodes may be Ag, Al, etc. Then, a material contg. an electro-optical material as an essential component separated to minute regions and a ferroelectric material are fixed with a dielectric material. In this case, an indicating part is constituted of a membrane consisting of a dielectric as a medium, thus an indicating body having an optional shape fitting not only to a plane surface but also to a curved surface is obtd. Moreover, cutting of the indicating body is possible because an electro-optical material is separated into minute regions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a transmissive type or reflective type display body constructed by utilizing the electro-optical effect of a substance.

[Conventional technology]

BACKGROUND ART Liquid crystal displays have long been known as display bodies that utilize electro-optic effects, and have high industrial value and are widely used in displays, optical shutters, and the like.

The basic structure of a conventional liquid crystal display is to form a so-called liquid crystal cell by holding substrates having electrodes facing each other with spacers. Furthermore, liquid crystal alignment within the cell before voltage application has been controlled by physically or chemically modifying the I&plate surface in contact with the liquid crystal. For physical or chemical modification, methods such as forming an alignment film on the substrate surface and then rubbing the surface, oblique evaporation method, grating method, etc. are well known methods, and these methods can control horizontal alignment, vertical alignment, and pretilt angle. It is used in

[Problem that the invention seeks to solve]

Since conventional liquid crystal displays use cells, the shape of the display section is limited by the shape of the substrate, and it is difficult from a technical and cost standpoint to obtain a display section with a curved surface or an arbitrary shape. Furthermore, when the cell is enlarged to increase the display area, the substrate FLrX1 is filled with weak liquid crystal, so when pressure or stress is applied to the substrate, the distance between the electrodes changes and the display characteristics change. It has the disadvantage of causing problems.

Moreover, it is difficult to freely select the orientation direction and obtain orientation control before applying a voltage, and the process also involves orientation control, which poses a problem in productivity.

The present invention overcomes the above-mentioned drawbacks, and allows the shape of a display using the electro-optic effect and the orientation direction of the substance that develops the electro-optic effect to be freely selected before voltage application, and
The purpose is to provide a display body with excellent strength and productivity.

Means for Solving Problem C] The present invention provides a display body driven by voltage application, in which a display part existing between opposing electrodes contains a substance that fosters an electro-optic effect divided into minute regions as an essential component. It is characterized by consisting of a material containing a ferroelectric material, and a dielectric material surrounding the ferroelectric material.

The basic structure of a display according to the present invention is shown in FIG. 1 as an example. A material 2 containing a substance that fosters an electro-optic effect as an essential component and a ferroelectric material 3 are divided into minute regions in the region sandwiched between the electrodes 1, and are distributed in a dielectric material 4, which is a medium, at an arbitrary density. .

The electrodes are transparent electrodes S now , I n * O
s * Z n O, Cd 2 O, a single substance, or one to which a torhant such as Sb is added can be used, and in the case of a reflective display, it is also possible to use an electrode of Ag, Aρ, Au, etc. on one side. These *ti can also be formed into a curved surface using a sputtering method, a vacuum evaporation method, a CVD method, or the like.

Next, microencapsulation technology can be applied to divide a material containing a substance having an electro-optic effect as an essential component into micro regions. Microencapsulation of liquid crystals has already been carried out, mainly using cosalvation methods, interfacial polymerization methods, etc. Capsule particle size is color density, #
It can be arbitrarily determined by taking into consideration the dispersibility in the X substance and the size that allows the constituent molecules to move freely within the capsule.

The ferroelectric material is preferably one that exhibits a ferroelectric phase within the operating temperature range of the display, and the material can be freely selected depending on the operating temperature. Furthermore, the magnitude of spontaneous polarization is
The magnitude is selected to produce a local electric field that is sufficient to control the orientation of the substance that has the electro-optic effect. In addition, since the spontaneously polarized crystal has grown a domain structure, it is desirable to make it into a fine powder to the extent that it has a monodomain structure in order to obtain an active local electric field. B as a ferroelectric material
a T f Os , K N b Os , etc.
Choose one that has a buskyte structure or one that has a ferroelectric phase that covers the operating temperature range, such as NaNOs.

In the present invention, a material containing as an essential component the substance that fosters the electro-optic effect divided into the micro regions shown above, and a!
The dielectric is fixed by the dielectric. The dielectric used here is one that hardens from a liquid phase to a solid phase by heat, light, chemical reaction, or the like. For example, microencapsulated liquid crystal and ferroelectric material are dispersed in the liquid phase while the dielectric material is in the liquid phase, and the liquid phase is cured from the liquid phase to the solid phase while applying a voltage in an arbitrary alignment direction (so-called poling). At this time, it is necessary that the ferroelectric material be fixed in the dielectric material while being poled in the alignment direction. In this case, it is necessary for the ferroelectric substance to rotate freely in the liquid phase of the dielectric substance, and it is necessary to select the powder particle size of the ferroelectric substance in consideration of the viscosity of the liquid phase and the like. It is desirable that the applied voltage be equal to or higher than the coercive electric field of the ferroelectric material used, taking into account the possibility that the powder particles may leave a domain structure.

Possible methods for forming the dielectric include a method using a thermosetting or photocurable resin, and a method in which a polymer is polymerized from a monomer. Of course, a ferroelectric material may be used as the dielectric material.

The Q degree and ratio of the material containing a substance with an electro-optic effect as an essential component and the ferroelectric in the dielectric are determined by the dielectric constant of the material used, the magnitude of spontaneous polarization, and the strength of the electric field required for orientation. Select the optimal value by considering the

If the display section is formed by the method described above, the liquid before hardening can be sold short by the DiP method, the spinner method, etc., and the display section can be formed not only on flat surfaces but also on curved surfaces.

The display section sandwiched between opposing electrodes is made up of a polarizing plate, a reflecting plate,
It can be combined with a 174 wavelength plate, etc., and can be used in exactly the same way as the cell system used up until now.

A protective film may be formed to protect the electrodes in contact with the outside world, and if the substrate supporting the electrodes is made thinner, a type-N type display body, which has not been thought of until now, is also possible.

Optically, by bringing the refractive indexes of the amounts of substances present in the display portion close to each other, it is possible to prevent light scattering by minute regions, and a display body with good transmission characteristics can be obtained.

In addition, after forming a display part by applying a voltage in one direction, a second layer display part is formed by applying a voltage in a different direction, thereby forming a display body having two layers with different orientation directions. ,
Furthermore, a multilayer structure can be easily realized.

[Effect]

The ferroelectric material in the display section has its spontaneous polarization forcibly oriented and fixed in an arbitrary orientation direction by the dielectric material that has hardened from a liquid phase to a solid phase. A substance that has an electro-optic effect is oriented according to the local electric field generated by this ferroelectric.＠ Next, when a voltage is applied between the electrodes, an electric field is generated between the electrodes, and a substance that has an electro-optic effect follows this. is oriented. The voltage required for orientation at this time is efficient if selected to produce an electric field smaller than the coercive electric field of the ferroelectric material and larger than the electric field required for orientation of the substance that fosters the electro-optic effect. When the voltage is removed again, the substance having the electro-optic effect will be oriented according to the local electric field formed by the ferroelectric material.

FIG. 2(a) shows an enlarged view of the orientation of the material exhibiting the electro-optic effect when a voltage is applied, and the two-layer diagram (b) shows an electro-optical effect when the voltage is applied. The orientation direction of a substance having an electro-optic effect is shown by a dashed arrow 1, and the direction of spontaneous polarization of a ferroelectric substance is shown by a solid arrow 2.

In FIG. 2, the forced orientation direction before voltage application is parallel to the electrodes.

In this way, by controlling the orientation of substances with electro-optical effects using the electric field created by the ferroelectric material inside the display section and the external voltage applied between the electrodes, it is possible to freely control the orientation according to electrical signals. It is.

Hereinafter, the display body of the present invention will be described with reference to Examples, but the present invention is not limited thereto.

〔Example〕

Liquid crystal ZL manufactured by Merck & Co., Ltd. is a substance with electro-optic effect.
Using a mixture of I-3200, 20% and ZLI-2806, 80%, liquid crystal was microencapsulated using a complex and a coacervage container. The particle size of the microcapsules was about 10 g. Next, as a powder ferroelectric material, B with a particle size of Q, 04 um to Q, 06 tLm is used.
aT i O.

A powder was prepared and dispersed in ethanol. (The solid content was 30 wt% based on ethanol.) This BaT
i O, 400 g of dispersion, 300 g of partially hydrolyzed γ-glycidoxypropyltrimethoxysilane, 0.2 g of flow control agent (manufactured by Nippon Unicar Co., Ltd.)
L-7804″) and 86 g of 0°05N acetic acid aqueous solution,
In addition to 200 g of ethanol, 30 g of microencapsulated liquid crystal was added, and the mixture was stirred at room temperature for 2 hours.

The liquid shown above is used as a coating liquid, and the viscosity of the coating liquid is 80.
It was precondensed until it became cps.

The coating solution prepared above was applied by dipping at a pulling speed of 20 cm/min onto a transparent glass substrate to which an ITO film and extraction electrodes had been attached in advance. Next, in a hot air drying oven, a direct current machine Q 10 K V /
130°C for 30 minutes at 80°C while applying cm
It was heated and cured for 2 hours.

After that, ■TO@ as a transparent electrode on the cured coating film.
was formed by the sparitaring method, and an extraction electrode was attached to form a display sample.

When the display sample was operated with EiOHz IOV static drive, the transmittance was 42 when the voltage was OFF.
%, it was 9.7% when ON.

〔Effect of the invention〕

By changing the display portion of the display body from a cell type to a film using a dielectric medium, the shape can be arbitrarily selected, and the display body can be formed not only on a flat surface but also on a curved surface. Furthermore, by dividing the substance that enhances the electro-optic effect into minute regions, the display body can be cut after forming the display body, and production can be performed quickly without designing cells.

In addition, by using a ferroelectric substance for orientation control and providing flexibility in the orientation direction, it has become possible to obtain a desired orientation direction more easily than with conventional rubbing methods. Furthermore, if the dielectric material between the electrodes is made stronger,
Even if the display area is large, it is possible to form a display body with such strength that there is no distribution in the strength of the display area, compared to a cell-shaped display body that uses spacers.

Application fields include regular display panels, optical shutters,
Of course, there are fields where cell systems have been applied until now, such as
Since it can be formed into curved surfaces such as the surfaces of optical lenses, it opens up completely new applications such as electronic sunglasses.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a display according to the present invention. 1... Electrode 2... Material containing as an essential component a substance having an electro-optic effect divided into minute regions 3... Ferroelectric material 4... Dielectric material Figure 2 (a) is according to the present invention FIG. 3 is a diagram showing a state in which no electric field is applied to the display body. FIG. 2(b) is a diagram showing a state in which an electric field is applied to the display according to the present invention. Applicant Seiko Epson Co., Ltd. Agent Patent Attorney Tsutomu Mogami - 1 other person -

Claims (1)

[Claims] In a display body driven by voltage application, the display part existing between opposing electrodes is made of a material containing as an essential component a substance having an electro-optic effect divided into minute regions, a ferroelectric material, and a dielectric material surrounding them. A display body characterized by consisting of a body.