JPS59189318A - Production of multicolor display device - Google Patents

Abstract

PURPOSE:To obviate deviation in patterns even if display patterns are fine and to enable color change without application of special prevention for dying by using a thin conductive film on a substrate as an electrode and forming a colored layer by electrodeposition from a soln. prepd. by dispersing a high polymer and a dye hardly soluble or insoluble in water. CONSTITUTION:A methyl cellosolve dissolved therein with a dye is added to an aq. soln. dissolved therein with ''ESVIA ED-3000'' to disperse uniformly the dye therein. A display substrate 6 on which display electrodes 7 is formed is dipped in such electrodeposting bath. The electrodes desired to be colored to the same color among the electrodes 7 patterned to a stripe shape are selected and 10V voltage is impressed for 3min on the selected electrodes as an anode. The substrate 6 is pulled out after the conduction of electricity and is thoroughly rinsed so that the soln. sticking on the parts not impressed with the voltage is washed away. When the substrate is dried after the rinsing, the colored layer having good transparency is formed on the electrodes impressed with the voltage. The polyester resin and melamine resin in the colored layer formed by the electrodeposition are stoved to effect a condensation reaction, by which the resins are cured.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for manufacturing a multicolor display device using a color filter, and in particular, to a method for manufacturing a multicolor display device using a color filter. The present invention relates to a method of manufacturing a multicolor display device.

Conventional technology Figure 1 shows a multicolor display device σ that uses color filters.
) - gave an example. In FIG. 1, 1 is a transparent substrate, 2 is a display electrode made of an HFR transparent conductive film patterned with arbitrary figures or characters, 3 is a color filter formed in close contact with the surface of the display electrode 2, and 4 is transparent. 5 is a transparent counter substrate.

The space between the two substrates 1 and 5 is filled with a substance, such as liquid crystal or electrochromic material, that functions as an optical shutter that opens and closes when voltage is applied, and the color filters 5.3' and 5'' are colored in different colors. If the display electrodes 2, 2/2, 211 and the counter electrode 4 are formed in such a manner that a voltage is selectively applied between them, multicolor display is possible.

Multicolor display using color filters is a simple method, it is easy to obtain free color tones, and it is thought that it can be used in combination with various display materials and methods, so it has extremely large practical effects.

However, when manufacturing a multicolor display device using color filters, it is necessary to manufacture the display device in such a way that there is no misalignment between the pattern of the display electrode and the pattern of the color filter formed on the surface of the display electrode. No. In particular, 3
When attempting to realize a graphic display using fine patterns of primary colors, pattern matching between display poles and color filters is an important issue that is difficult to manufacture. The process of obtaining one or more colors is also a factor that complicates the process, especially when trying to achieve coloring by dyeing, the area that is colored M in the first step is dyed twice in the next dyeing process. The process of resist dyeing is added in between, making the process even more complicated. Furthermore, the resist dyeing technique itself is a problem that must be considered individually depending on the dye.

Generally, the way to create all color filters is as follows:
Methods using methods such as screen printing and photophosphorography are being considered. Screen stamp ■1j does not require resist dyeing, but there is a limit to the miniaturization of the pattern.
As the number of colors increases, the precision of the printing position deteriorates, causing misalignment with the displayed pattern. Although it is possible to create fine patterns with photolithography, it is necessary to go through one photolithography process each time, and a resist dyeing method that prevents double dyeing is required9. This becomes extremely complicated, and the advantage of a simple means for multicoloring is lost.

Purpose of the Invention Therefore, the present invention provides a simple method that does not cause pattern shift even when the display pattern becomes fine, that can be used without any special resist dyeing, and that provides a robust color filter. The purpose of this study is to propose a manufacturing method for a multicolor display device using a conductive thin film 'r'l!' on a substrate. A color filter is manufactured by using a method in which a colored layer is formed by electrodeposition from a solution in which a polymer and a dye that is sparingly soluble or insoluble in water are dispersed.

According to this method, a conductive thin film is patterned in a desired manner by vapor deposition, sputtering, or etching using a mask, and then polymers and dyes are selectively electrodeposited on conductive areas to which a voltage is applied. However, it is possible to form a dark blue layer with no deviation in pattern position. Furthermore, by repeating this operation, a colored layer will not be formed again on the part that has been electrodeposited once, so it is possible to easily create multiple colors. If the substrate used in this method has an insulating surface, a conductive thin film layer with good adhesion to the substrate is selected, and there are no restrictions on its material and shape.
No.

Structure of the Invention The method for forming a colored layer by electrodeposition of a polymer, which is an important point of the present invention, will be described below. One method for electrodepositing a polymer on an electrode is to electrochemically polymerize a monomer on the electrode. As an example of this method, there is a report that a polymer film was obtained by electrochemically polymerizing various vinyl compounds on an iron plate (Metal Surface Technology Vol. 1.19).
．． AI2.1968). Also, recently, pyrrole,
6- Research is also actively being carried out on electrochemically polymerizing offene and the like to create conductive polymers such as polypyrrole and polythenylene on electrodes. However, such a method of directly electrochemically polymerizing monomers is not suitable for use in the present invention because the efficiency is still low, the obtained film is already colored, and the coloring is not arbitrary. has problems. Another method of electrodepositing polymers on electrodes is
There is a method in which polymers are deposited on the electrode from a polymer solution in a bath-free manner. As an example of this, a pigment is completely dispersed in an aqueous polymer solution, a metal is immersed, and used as an electrode.
It's called electrodeposition painting, in which the M color layer is electrodeposited.

This method is known industrially and is used for pre-coating automobile bodies. The principle of this method is to introduce a hydrophilic group, such as a carboxyl group, into a polymer, and then neutralize the carboxyl group with an inorganic alkali, organic amine, etc.
Use water-soluble one. Then, when the electrode is immersed in an aqueous solution of the water-soluble polymer and a full voltage is applied, the carpoquine anion dissociated in the water bath solution is electrophoresed toward the anode, and is generated by electrolysis of water on the electrode. By reacting with protons, the polymer is insolubilized and precipitated. That is, the reaction shown in the following formula occurs on the anode, and polymer precipitation is observed.

2H20-)4H++02↑+4e- If a basic group (for example, polyamine) is used as the hydrophilic group and is neutralized and water-solubilized with an acid, on the contrary, polymer precipitation will be observed on the cathode.

If the electrodeposited polymer is electrically dense, the current decreases as the electrode is coated with the polymer, preventing further coating, so an increase in film thickness cannot be expected.
In reality, due to the bubbles of oxygen generated by the electrolysis of water, complete coating is avoided in the initial stage, and a certain degree of film thickness is obtained by the time it becomes an insulating layer. Usually, 100~ for electrodeposition coating
A film thickness of 10 to 20 μm was obtained by applying a voltage of 200 V. However, in the color filter according to the present invention, the colored layer should be thinner, and preferably 2 μm or less. It is necessary to appropriately set the resin concentration, voltage, and solvent composition 1.Also, the resulting polymer film has a low water content due to the effect of electroosmosis, and has a uniform and better adhesion than films made by coating methods. It becomes a membrane.

Polymers for anion electrodeposition include adducts of natural drying oil and maleic acid, alkyd resins with carboxyl groups introduced, adducts of epoxy resins with maleic acid, polybutadiene resins with carboxyl groups, acrylic acid ff, or A copolymer of methacrylic acid and its ester is used, and depending on the properties of the fixing film, another polymer film or an organic compound having a functional group may be introduced into the polymer skeleton. When viewing light through a color filter as in the present invention, transparency is required for the colored layer, and acrylic or polyester polymers are suitable for the material.

- Also, the amount of hydrophilic functional groups such as carboxyl groups and hydroxyl groups in the polymer is important; if there are too many hydrophilic groups, the electrodeposition layer will not be sufficiently insolubilized, resulting in an uneven film, and if there is too little, it will be neutralized. water solubility becomes insufficient. Water is the main component of the solvent for high 9-molecules, and examples include inpropatol, n-buzaltylchol, t-7'' ethyl alcohol, methyl cellosolve, ethyl cellosolve, isopropyl cellosolve, and butyl cellosolve.

Aqueous solvents such as diethylene glycol methyl ether, diethylene glycol ethyl ether, and diacetone alcohol are included as solvents for polymerization of polymers. The type and amount of the hydrophilic solvent included greatly influences the film thickness and uniformity of the electrodeposited layer.

The method of coloring is that pigments are used in electrodeposition coating, and the charged pigments are electrophoresed together with polymers and incorporated into the film, but in the case of transparent color filters like the one of the present invention, pigments are hidden. is not necessary, and if the film thickness becomes thin, the degree of coloring will be lacking. Therefore, in the present invention, a method was devised in which a dye is electrodeposited together with a polymer. In order to electrodeposit the dye along with the polymer, the dye molecules are charged and! However, in the case of water-soluble dyes, the dissociated dye ions have the effect of adding a supporting salt, resulting in increased current, increased film thickness, and non-uniformity of the film. appear. Dyes that are sparingly soluble or insoluble in water usually aggregate in water, but electrodeposited polymers can be regarded as a type of soap with hydrophobic and hydrophilic groups, and to some extent, organic dye molecules It was discovered that it exhibits a dispersion effect, and that it can be made into fine particles by combining with a suitable dispersion medium, and that it can be electrodeposited together with polymers. In this case, it is necessary to make the electrodeposition rates of the dye and the polymer comparable, but this can be controlled by the solution composition.

EXAMPLES Below, a method for manufacturing a multicolor display device using color filters will be explained in detail based on examples.

(Example 1) FIG. 2 is an application example of a multicolor display device to which the method of manufacturing a color filter according to the present invention is applied.

Hereinafter, a method for manufacturing a multicolor display device as shown in FIG. 2 will be specifically described.

(2) In the patterning step 6, a display substrate made of a transparent material is used, and a tin oxide transparent conductive film is formed on the display substrate by a spray coating method.

The entire transparent conductive film is patterned into stripes by etching, and the display '1! Get pole 7.

(2) Electrodeposition process Next, an electrodeposition bath having the following composition is prepared using a paint having the following composition (Nispier FD-3000 manufactured by Shinto Nuribetsu) Nisvia ED-3[]00.

The oil-soluble dyes to be used are limited to those soluble in hydrophilic solvents, and those having a metal complex salt structure with very good light resistance are preferable. For example, some molecules have a molecular structure af as shown in the following formula.

(The product name is Aizen 5pilon, 01eo8
o11 H3 Color Index Number 5o1vent Rea 8・
The bath preparation procedure is to dissolve Nisbia BD-3DODi in water. The dye is then dissolved in methyl cellosolve. At this time, the dye weight ratio X is arbitrarily selected within a range that does not exceed the solubility Kk of the dye in methyl cellosolve. Methyl cellosolve in which the dye has been completely dissolved is added to the aqueous solution to uniformly disperse the dye. At this time, methyl cellosolve acts as a dispersion medium, but when the amount of rh added increases or the number of carbon atoms in the alkyl group -16- of cellosolve increases, the film thickness increases and the film becomes unbound.

The display base 8!6 on which the display electrode 7 is formed is immersed in the electrodeposition bath prepared as described above. Select the electrodes to be colored in the same color among the strain display electrodes 7 patterned in a stripe shape, and apply a voltage of 10 V for a total of 3 minutes to the selected electrodes f'' for a total of 3 minutes.At this time, the current is applied immediately after coupling. , a large current flows, but it gradually decreases and approaches 0.

After energization, the display substrate 6 is pulled up and thoroughly washed with water to wash away the bath liquid adhering to the parts to which no voltage is applied. After washing with water and drying, a highly transparent colored layer is formed on the electrode to which voltage has been applied.

(2) Curing process Next, the polyester resin and melamine resin in the colored layer formed by electrodeposition are baked to undergo a condensation reaction and cured. The colored layer is completely cured by baking at 175°C for 60 minutes in the air. The thickness of the colored layer at this time is -14-1,5 It? It was yl.

The cured colored layer is a complete insulating layer, and even if it is immersed in the electrodeposition bath again and energized twice, no redeposition or double dyeing will occur. This is achieved by selecting another display electrode of the same color again and performing the steps of electrodeposition and curing in an electrodeposition bath in which a dye of a different color tone is completely dispersed.

In this example, striped color filters 8 with a width of 200 μm in the order of red, blue, and green are formed in a buttering process → red electrode electrodeposition process → curing process → blue electrode electrodeposition process → curing process → It is manufactured using the electrodeposition process of the green "LI!" electrode followed by the curing process, and is extremely simple to perform.The resulting color filter shows no color shift, is uniform, and is resistant to acids, alkalis, and various other substances. Organic solvent.

Is it resistant to being exposed to hot water, etc.? had. Further, the metal complex dye used was extremely stable in the colored layer, and even after 360 hours of the carbon arc test, it exhibited a value of 95 or more of the initial light absorption coefficient, and had excellent light resistance.

In this way, a force 1 is formed on the color filter 8 on the display electrode Z, and a transparent counter electrode 9 is formed on the display substrate 6 in the form of a stripe. The stripes of the electrode 7 and the opposite electrode 9 are integrated so as to cross at right angles to form a cell.

The display material 12 and L7 were filled with TN-F'EM; liquid crystal to produce a multicolor liquid crystal display device. in this case,
A voltage is applied between the display 'i1\ electrode 7 and the counter electrode 9, and the display board 6 is sandwiched between a polarizer and an analyzer whose total cell transmission axes are parallel.
Alternatively, when viewed from the direction of the opposing group filo, the color of the transparent color filter 8 is displayed, and when the voltage application is stopped, the color becomes black. Opposite group f! When combined light is irradiated from a directional force of 10), the transparency of the cell is good, and the color of the color filter 8 is displayed more effectively. In this way, although the method of dipping the multicolor display device in this example is a simple manufacturing method, it is possible to obtain a color filter with a fine pattern without impairing the display quality, and it is reliable. It has been found that the present invention is suitable for providing matrix-driven color graphic displays of high quality.

(Example 2) The following procedure was the same as in Example 1, except that the display material 12 in Example 1 was a negative type guest phosphor using a black dichroic dye, and the FI display substrate 6 was a white material (white ceramic). A complete multicolor liquid crystal display device was created. In this case, the display electrode 7
A voltage is applied between the opposite electrode 9 and the color filter 8 when viewed from the direction of the transparent opposite substrate 10 through the polarizing plate.
The color is displayed brightly, and when the voltage application is stopped, the color changes to black, which is the color of the dichroic pigment in the liquid crystal. Also in this example,
The same effect as in sister example 1 was obtained.

EXAMPLE The display material 12 in Example 1 was a DSM liquid crystal, and aluminum was patterned into the display substrate 6 by mask evaporation to form the display electrodes 7. A multicolor liquid crystal display device was then produced in the same manner as in Example 1. In this case, a full voltage is applied between the display electrode 7 and the counter electrode 9, and when viewed from the direction of the transparent counter group 8!1o, the DSM liquid crystal becomes a light scattering state, and the color filter 8 appears in the milky white inside = 17-. Color is displayed. When the voltage application is stopped, the light scattering state disappears, resulting in a dark state. In order to efficiently generate the light scattering state of the EIM liquid crystal, it is necessary to flow an IW ion current to a certain extent, and the high resistance of the color filter 8 (the high resistance of the color filter 8 prevents this. Therefore, a pattern is formed on the color filter 8. By providing a Hideaki electrode that coincides with the display chamber $7 and using the transparent electrode as the pole for applying pressure, the driving voltage can be completely reduced, and the same effect as in Example 1 can be obtained. It was done.

(Example 4) Using the electrodeposition bath in Example 1 below, an electrodeposition bath having the following composition was prepared using Powermite 3000-10, a paint with a composition of 5e (Powermite 6000-10 manufactured by Nippon Paint).

-18- Commercially available disperse dyes often contain anionic dispersants or anionic dispersants (this dispersant turns into ions in the bath and increases the current value). It is preferable to use a bath that does not contain a dispersant, as this can cause dispersion.The method for preparing the bath is to dissolve the disperse dye in x (uniformly dispersed in ethylene glycol in the range of 1.5, Power My) 3000-10i water. Add to the solution.

Hereinafter, a multicolor liquid crystal display device was produced in the same manner as in Example 1, and the same effects as in Example 1 were obtained. However, it has become clear that only a limited number of dyes, such as metal complex type oil-soluble dyes, have the property of quickly f''L when it comes to the light resistance of color filters.

Example The electrodeposition bath in Example 1 had the following composition.

The method for adjusting the bath in this case is to add an oil bath dye to Nisbia ED-3000 in the range of x (1, 0) and disperse it uniformly by kneading, ultrasonication, etc. Then, add water and Hereinafter, a multicolor display device was created in the same manner as in Example 1, and the same effect as in Actual Example 1 was obtained (f'L).In this case, the polymer concentration in the electrodeposition bath Because it is expensive, the colored layer is 2.
The thickness was 0 μm. Oil bath dye used in this example (
is not limited to dyes that are soluble in hydrophilic solvents, but it goes without saying that dyes with excellent light resistance are desirable.

In addition to the effects of the invention, as specifically described in the actual examples, the method for manufacturing a multicolor display device according to the present invention is simple and requires special methods such as resist dyeing to separate the colors for multicolorization. Color filters can be manufactured without using any means. Furthermore, the color filter is robust and free of pattern shift, and can achieve high display quality and reliability even when combined with display materials such as liquid crystal.

[Brief explanation of drawings]

Figure 1 is an example of a multicolor display device that uses color filters. FIG. 2 is an example of a multicolor display device manufactured by the manufacturing method of the present invention. 1.6... Display board 2.7... Display electrode 3.8... Color filter 4.9... Counter electrode 5.10... ...Counter substrate 12 ...Display material Applicant Daini Seikosha Co., Ltd. Figure 1 Figure 2

Claims (5)

[Claims] (1) In a multi-color display device using color filters, the color filters are placed on a substrate with first
Then, on the conductive layer of soft straw, a bath solution containing an electrodepositable polymer and a moisture-resistant or water-insoluble dye is selectively applied to the electrodeposited layer. 1. A method for manufacturing a multicolor display device, comprising forming a colored layer and repeating the operation using dyes of different colors. (2) A plurality of conductive layers are disposed on the substrate in a mutually discontinuous manner;
It is a transparent conductive layer mainly composed of antimony oxide, and the formation of a yellowish layer based on a polymer layer selectively electrodeposited on the transparent conductive layer basically includes an anionic electroactive polymer. 2. The method of manufacturing a multicolor display device according to claim 1, wherein the colored layer is formed based on a polymer layer that is a-deposited from a bath solution by electrolysis. (3) The anionic electrodepositable polymer may be acrylic to τ1 resin having a carboxyl group, a polyester resin having a carboxyl group neutralized with an alkali to make it water-soluble, or a water-soluble melamine resin added to them. 2. A method for manufacturing a multicolor display device as claimed in claim 2, characterized in that the multicolor display device is made of a single color. (4) The method for manufacturing a multicolor display device according to claim 1, wherein the water-insoluble dye is a disperse dye or an oil-soluble dye. (5) The method for manufacturing a multicolor display device according to claim 4, wherein the oil-soluble dye has a metal complex salt structure and is soluble in a hydrophilic solvent.