JPH01145636A - Production of liquid crystal display body - Google Patents

Abstract

PURPOSE:To form a display part on a curved surface and to prevent clouding at the time of non-operation by dispersing microcapsules and ferroelectric material into a curable material and curing the curable material while impressing an electric field and/or magnetic field thereto, thereby forming the title liquid crystal display body. CONSTITUTION:The display body is formed by dispersing the microcapsules 1 and the powdery ferroelectric material 2 and/or a ferroelectric liquid crystal 2 sealed in the microcapsules into the curable material and curing the curable material while impressing the electric field and/or magnetic field thereto. The microcapsules 1 are, therefore, fixed in the curable material and the liquid crystal is oriented in the fixed microcapsule 1 in the direction where the electric field and/or magnetic field is impressed. Furthermore, the ferroelectric material having spontaneous polarization is forcibly oriented and fixed by the curable material and, therefore, the local electric field is generated and is helpful for the orientation of the liquid crystal in the microcapsules. The use of this display body in the same manner as an ordinary cell type is thereby enabled and the display on the curved surface is enabled as well.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method of manufacturing a transparent-convex or reflective 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-optical 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, microcapsules encapsulating liquid crystals are mixed into paints, etc., and used as a display body in the form of a coating film.

[Problem that the invention seeks to solve]

When microcapsules filled with liquid crystal were used, there was an advantage that the display section could be formed on a curved surface, but the display became cloudy when not in operation.

This was because the alignment of the liquid crystal could not be controlled when it was not in operation. It is still useful when used as a reflective type, but
If you try to adjust the amount of light by transmitting it, it becomes cloudy, which is a problem.

The present invention overcomes the above-mentioned drawbacks, and aims to provide a liquid crystal display that can form a display part on a curved surface and maintain a constant transmittance without becoming cloudy when not in operation. do.

[Means for solving problems]

In a liquid crystal display driven by voltage application, the present invention provides a display portion existing between opposing electrodes using microcapsules encapsulating a material containing liquid crystal or liquid crystal added with a dichroic dye as an essential component, and a powder-like liquid crystal display. It is characterized in that it is formed by dispersing a ferroelectric material and/or a ferroelectric liquid crystal encapsulated in microcapsules in a curable substance, and then curing the curable substance while applying an electric field and/or a magnetic field.

In the present invention, microcapsules are first dispersed in a curable substance such as thermosetting or photocurable material. In this case, it is necessary that the microcapsules can freely rotate in the liquid curable substance, and it is necessary to select the particle size of the microcapsules in consideration of the viscosity of the liquid phase and the like. Furthermore, in the present invention, a powdered ferroelectric material and/or a ferroelectric liquid crystal encapsulated in microcapsules are simultaneously dispersed into this curable material.

The ferroelectric material is preferably one that exhibits a ferroelectric phase within the operating temperature range of the liquid crystal display, and the material can be freely selected depending on the operating temperature. Furthermore, the magnitude of the spontaneous polarization is selected so as not to generate a local electric field sufficient to control the alignment of the liquid crystal. In addition, since a spontaneously polarized crystal has 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 effective local electric field.

In this way, a coating liquid in which microcapsules or finely powdered ferroelectric material are dispersed is applied in advance to a substrate on which transparent electrodes are formed. The coating method can be a DiP method, a spinner method, or the like.

In the present invention, an electric field and/or a magnetic field is applied to the coating film until the curable substance finishes curing. The strength of the electric field and magnetic field is preferably such that the orientation of the liquid crystal does not change within the microcapsules, and the microcapsules rotate.

After curing, a transparent electrode can be formed on the coating film and used as a display.

In addition, after forming the display part by applying an electric field and/or magnetic field in one direction, by forming the second layer display part by applying an electric field and/or magnetic field in another direction, it is possible to form the display part in the orientation direction. It is possible to easily form a display body having two layers with different values, and even realize a multilayer structure.

[Effect]

In the present invention, the dipole moments of the microcapsules and powdered ferroelectric material in the liquid phase before curing are disordered as shown in FIG. (The dipole moment of the ferroelectric is shown by a solid line, and the dipole moment of the microcapsule is shown by a dashed arrow.) Next, when an electric field and/or magnetic field is applied parallel to the substrate in the liquid phase, as shown in Fig. wi2. , the dipole is oriented in the direction of the applied voltage. If the dielectric medium is hardened in this state, microcapsules will be created.
The powdered ferroelectric remains oriented in a certain direction without being subjected to thermal disturbance. By also orienting the ferroelectric material,
A local electric field is created, which also contributes to the alignment of the liquid crystals in the microcapsules, making them more aligned than they would be without the ferroelectric material.

Hereinafter, the electronic sunglasses of the present invention will be described with reference to Examples, but the present invention is not limited to these.

〔Example〕

Merck ZLI-3200 as a guest-host type liquid crystal
, 20 wt% and ZLI-2806, 80%, and the liquid crystal was microencapsulated using Conoplex Coacervage GNO. The particle size of the microcapsules was about 10μ. Next, B aTi with a particle size of 0.049 m to 0.06 μm was used as a powder ferroelectric material.
O, powder was prepared and dispersed in ethanol. (The solid content was 30 wt% based on ethanol.)
400 g of aT i Os dispersion, 300 g of γ-glycidoxypropyltrimethoxysilane partial hydrolyzate,
0.2 g of a flow control agent ("L-7604" manufactured by Nippon Unicar Co., Ltd.) and 86 g of a 0.05N acetic acid aqueous solution were added to 200 g of ethanol, and 35 g of microencapsulated liquid crystal was added, followed by stirring at room temperature for 2 hours. Ta.

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 to a diethylene glycol bisallyl carbonate substrate on which an ITO film and extraction electrodes were attached in advance by a dipping method at a pulling rate of 15.
It was applied at a rate of cm/min.

Next, in a hot air drying oven, a DC electric field of 2 0 is applied in a direction parallel to the substrate.
80 °C for 30 minutes while applying KV/cm, 13
It was heated and cured at 0°C for 2 hours. Thereafter, an ITO film was formed as a transparent Ti electrode on the cured coat crotch by a sputtering method, and an extraction electrode was attached to form a suction/pull.

When the display sample was statically driven at 60 Hz 10 V, the transmittance was 40% when the voltage was OFF and 9.2% when the voltage was ON.

〔Effect of the invention〕

When focusing on one microcapsule, it can be seen as one dipole moment.

When the curable material is cured while applying an electric field and/or a magnetic field, the microcapsules are fixed in the curable material. The liquid crystals in the fixed microcapsules are oriented in the direction in which the electric and/or magnetic fields are applied. Furthermore, because the ferroelectric material that develops spontaneous polarization is forcibly oriented and fixed by a hardening substance, a local electric field is generated, which helps to orient the liquid crystal inside the microcapsule. In addition, when the voltage is turned off after being activated by applying a voltage, the return speed is quick.

By making it possible to control the orientation of microencapsulated liquid crystals, it is now possible to use them in the same way as normal cell-type liquid crystals, and it is also possible to display on curved surfaces.

Application fields include not only ordinary display panels, optical shutters, and other fields where the cell method has been applied until now, but also the ability to form curved surfaces such as optical lens surfaces, opening up completely new applications such as electronic sunglasses.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the state of the dipole moment as a microcapsule and the state of the dipole moment of a ferroelectric substance before voltage is applied in the liquid crystal display of the present invention. FIG. 2 is a diagram showing the state of the dipole moment as a microcapsule and the state of the dipole moment of a ferroelectric material when voltage is applied in a direction parallel to the substrate. 1... Microcapsule 2... Ferroelectric material 3... Transparent electrode 4... Substrate is shown. Applicant: Seiko Epson Corporation

Claims (1)

[Claims] In a liquid crystal display that is driven by voltage application, the display part that exists between opposing electrodes is made up of microcapsules encapsulating a material containing liquid crystal or dichroic dye-added liquid crystal as an essential component, powdered ferroelectric material, and A method for manufacturing a liquid crystal display, comprising: dispersing a ferroelectric liquid crystal encapsulated in microcapsules in a curable substance, and curing the curable substance while applying an electric field and/or a magnetic field.