JPS6048743B2 - Manufacturing method of liquid crystal cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a liquid crystal cell, and more particularly to a transparent insulating film made of zirconium oxide Zr()O formed on the surface of an insulating substrate.

Generally, the method of forming Zr()O transparent film is vacuum evaporation method,
The main methods are chemical spray method and dipping method.

Although the vacuum evaporation method has excellent coating properties, it has problems in mass production. Chemical spraying and dipping methods are suitable for mass production, but require etching to create display patterns, which increases the number of steps. In order to eliminate these drawbacks of the conventional example, the present invention enables screen printing and baking ZrO after printing.

Z of the desired shape is printed on the transparent electrode using the printing paste.
r0. The present invention provides a method for manufacturing a liquid crystal cell in which a transparent metal oxide film is formed. In order to achieve this object, the present invention uses organic zirconium in which acetylacetone is coordinated to zirconium that is soluble in an organic solvent and forms a Zr()2 film upon firing, an organic solvent, and a viscous agent. A paste with properties suitable for screen printing is made by mixing, this paste is printed in a predetermined pattern shape on an insulating substrate by screen printing, and then baked to remove the organic solvent and viscous agent, and Zr.
It is characterized by forming a transparent insulating film of O2.

As the organic zirconium compound, ordinary organic hydrochloric acids such as zirconium octylate Zr(C7H,5CO2)O can also be used, but particularly chemically stable zirconium tetraacetylacetonate Zr(C5H,O2
), (abbreviation Zr(acac)O), compounds in which zirconium is coordinated with acetylacetone (Hacac) are suitable.

In addition, examples of the organic solvent for dissolving the organic ziconium compound include high-boiling alcohols such as terpineol, 2-ethylhexanol, and benzyl alcohol; high-boiling esters such as benzyl acetate and dimethyl phthalate;
High boiling point organic solvents such as high boiling point alcohol ethers such as carbitol, butyl carbitol and butyl cellosolve are used, and cellulose compounds such as nitrocellulose and ethyl cellulose are used as viscosity agents. Using the paste made in this way, screen printing is performed using a screen plate patterned into the desired shape, and after preliminary drying, baking is performed at a temperature of 400°C or higher to produce Zr().

A transparent coating is formed into the desired shape. This film is not only transparent, but also has high film strength and relatively high insulation properties. In addition, metal zirconium (Z
By appropriately controlling the amount of r), a film of 5000A or less can be freely formed. Next, examples of the present invention will be described.

Example 1 In-. 0.

A transparent electrode is formed by sputtering. On the other hand, a printing paste was prepared with the following composition ratio. Zr(Acac
) 48.0 wt% Butyl cellosolve 81.0 wt% Ethyl cellulose (or nitrocellulose) 0 wt% Using this paste, screen print a predetermined pattern on the substrate on which the transparent electrode was formed using a screen plate of stainless steel net 250 mesh. After pre-drying at 150°C for 1 minute, the ZrO2 powder was fired at 500°C.
Forms a film.

Furthermore, ZrO.

Horizontal alignment agent (manufactured by Toray Silicone Co., Ltd., product name S) on the film
After forming an alignment treatment layer using H6O4O), the upper and lower substrates are lapped so that they are perpendicular to each other, and then the two substrates are bonded together using an epoxy adhesive so that the gap is IO.
Paste them together so that they become P7TL. This cell has a negative 3-take liquid crystal with positive dielectric anisotropy (manufactured by Chisso, product name: G).
R-61) is sealed, and polarizing plates are attached to the top and bottom of the cell so that the wrapping direction of the substrate and the polarization axis are parallel to each other, thereby completing a liquid crystal cell. Example 24f In2Oa on two insulating substrates, at least one of which is transparent.
A transparent electrode is formed by sputtering, and the printing paste shown in Example 1 is printed in a desired shape, pre-dried, and then baked at 500° C. for 30 minutes to form a ZrO2 insulating film.

Furthermore, a vertical alignment layer is formed using a chromium complex as a vertical alignment agent.
Two substrates were bonded together using an epoxy adhesive, and a liquid crystal cell was assembled using a nematic liquid crystal with negative dielectric anisotropy, which was made by adding 1 wt% of blue dye and 1.3 wt% of cholesteric liquid crystal, cholesteric liquid crystal. If sealed, a positive display phase change guest-host type liquid crystal cell is obtained. In order to compare the effects of the present invention, vinyl tris 2-methoxyethoxysilane (V-5000), Zn (Acac
).

, Ce (Acac). Using a paste for forming an insulating film containing each as a main component, the paste is fired to form SiO. ，
ZnO, Ce. A transparent insulating film of O3 was formed to make a ゛m liquid crystal cell, and these were used as Comparative Examples 1 to 3.
The following table shows the comparison results of the film forming properties of the transparent insulating film, the orientation of the liquid crystal material, and the changes in current value of the liquid crystal cells in comparison with the TN liquid crystal cells obtained by the method. In addition, in the film formability column of this table.

The mark indicates that the film thickness is uniform with no cracks, etc., the mark ○ indicates that there are no cracks, etc., but the film thickness is slightly uneven, and the mark x indicates that there are some cracks, etc. The orientation was determined by examining the orientation state after 2 hours in a pressure checker test at 120° C. and 2 atm. In this column, ○ indicates that there is almost no disclination, ×
The mark indicates that some discrepancy has occurred.
The current value change indicates the rate of change (multiply) of the current value after the above-mentioned pressure-jerker test with respect to the characteristic value at the initial stage of manufacture, and the 〇 mark in this column indicates that the current value change is less than 3 times. , Δ marks indicate a change in current value of 3 to 5 times, and × marks indicate a change in current value of more than 5 times.

Although the film using the method is excellent in film forming properties and orientation, the current value changes 3 to 5 times as much.

Those using a ZnO insulating film have problems in film formability, orientation, and changes in current value. Also Ce. O3
Those using an insulating film have somewhat good film formation properties, but have poor orientation and large changes in current value. Compared to these, those using the cell substrate according to the present invention have good film forming properties and orientation, and have excellent characteristics with little change in current value.
As described above, by forming this insulating film on a transparent electrode, TN type, phase change type, guest host type, DS type, etc.
Various other types of liquid crystal cells can be made.

Note that by forming this insulating film on a glass substrate, it becomes an anti-sodium film, which is effective in preventing deterioration of the liquid crystal material.

The present invention has the above-mentioned structure, and the organic zirconium compound in which acetylacetone is coordinated with zirconium is chemically stable and has good printability over a long period of time, and has good productivity and fine printability. It is possible to provide a method for manufacturing a liquid crystal cell in which a patterned transparent insulating film can be formed.

Claims (1)

[Claims] 1. A paste with properties suitable for screen printing is prepared by mixing an organic zirconium compound in which acetylacetone is coordinated with zirconium that is soluble in an organic solvent and forms a zirconium oxide film upon firing, an organic solvent, and a viscous agent. This paste was printed in a predetermined pattern on an insulating substrate by screen printing, and then baked to remove the organic solvent and viscous agent and form a transparent insulating film made of zirconium oxide. Characteristic method for manufacturing liquid crystal cells.