JP2632854B2 - Multicolor surface coloring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a field requiring high definition and multicolor, for example, a multicolor display device, a color filter of an image pickup tube, a multicolor scale of a microscope, and the like. The present invention relates to a multicolor surface-emitting color body used for a color image.

[Summary of the Invention]

The present invention provides a multi-color surface colored body made by using an electrodeposition method, a dummy electrode is provided around a transparent electrode substrate having an electrodeposition pattern having a mosaic shape, and the dummy electrode is formed simultaneously with the electrodeposition pattern. The present invention relates to a multicolor surface colored body characterized in that it can be colored.

[Conventional technology]

A method for producing a multicolor surface colored body includes a printing method, a photolithography method, and an electrodeposition method. The printing method has insufficient positional accuracy in multicolor printing, and it is extremely difficult to achieve high definition. Although the photolithography method is a satisfactory means in this respect, the manufacturing process becomes extremely multiplexed and complicated because the photolithography process is performed for each color. In the electrodeposition method, since electrodeposition and coloring are performed for each color on a transparent electrode patterned with high definition, the electrode pattern accuracy is realized as it is as the accuracy of a multicolor surface colored body, and at the same time, it is an extremely easy manufacturing method. It is characterized by having. Therefore, the electrodeposition method is most advantageous as a method for producing a multicolor surface colored body having a high-definition pattern.

When this electrodeposition method is used, the pattern shape of the transparent electrode is
The simplest is a stripe pattern. But,
In the case of a stripe pattern (particularly when used for a display element), since the distance between the colors is not equal, the degree of color mixture is small, and various patterns for improving this are being studied. For example, a mosaic pattern or a triangle pattern is used. However, in the case of the triangle pattern, the display pixels are alternately arranged as seen in FIG. 2, so that when the opposing substrate is an active element such as a TFT, forming the TFT element in accordance with the display element causes the arrangement of the TFT elements. However, there is a problem that the connection wiring of the gate line or the source line becomes zigzag, complicated and long, and the production yield of the TFT element is reduced.

In this regard, the use of the mosaig-like electrode pattern as shown in FIG. 3 eliminates the burden on the manufacture of the TFT element as described above, and at the same time, the color mixing degree is substantially the same between the respective colors. Good, no effect on display quality. Therefore, it can be said that the mosaic pattern is most suitable as the multicolor surface coloring material used for the display element.

When this mosaic pattern is used as an electrodeposition substrate, as shown in FIG. 3, the connection between pixels of the same color can be formed as diagonal lines, and the same line can be colored simultaneously by electrodeposition. By patterning such a transparent electrode in the form of an electrodeposited substrate, a desired color filter can be manufactured with the same number of electrodepositions as the required number of colors, similarly to the stripe pattern.

Here, the principle and method of electrodeposition used in the present invention will be described below.

This electrodeposition is a method of insolubilizing and precipitating a polymer on an electrode with a polymer solution, and is called a polymer electrodeposition method. As an example of this, a method called electrodeposition coating in which a pigment is dispersed in an aqueous polymer solution, a metal is immersed and used as an electrode, and a colored layer is electrodeposited on the metal is industrially known. And so on. The principle of this method is to use a polymer in which a hydrophilic group, for example, a carboxyl group is introduced into a polymer, and the carboxyl group is neutralized with an inorganic alkali, an organic amine or the like and made water-soluble. When an electrode is immersed in a water-soluble aqueous polymer solution and a voltage is applied, the dissociated carboxy anions in the aqueous solution move electrically toward the anode, reacting with the protons generated by the electrolysis of water on the electrode. The polymer becomes insoluble and precipitates. That is, the reaction represented by the following formula occurs on the anode, and deposition of the polymer is observed.

If a basic group such as a polyamine is used as the new aqueous group and neutralized with an acid and made water-soluble, a polymer will be deposited on the cathode.

When the electrodeposited polymer is electrically insulating, the current is reduced as the electrode is coated, and it is considered that the film thickness cannot be increased to prevent further coating. The initial complete coverage is avoided due to oxygen bubbles, and a certain film thickness can be obtained before becoming an insulating layer. Usually, in electrodeposition coating, a film thickness of 10 to 20 microns is obtained by applying a voltage of 100 V to 200 V, but when a multicolor surface colored body requiring high precision and high fineness according to the present invention is intended. The distance between the patterns is several tens of microns, and if the film thickness is too large, fusion between the patterns occurs. for that reason,
The thinner the colored layer, the better, and preferably about 1 micron. Therefore, it is necessary to optimally design the polymer resin concentration, applied voltage, and solvent composition.

The polymer film thus obtained has a low water content due to the effect of electroosmosis, and is a uniform film having better adhesion than a film produced by a coating method or the like.

Examples of the anion electrodeposition polymer include an adduct of a natural drying oil and maleic acid, an alkyd resin having a carboxyl group, an adduct of an epoxy resin and maleic acid, a polybutadiene resin having a carboxyl group, acrylic acid or methacrylic acid. A copolymer with the ester is used,
Depending on the characteristics of the electrodeposition film, another polymer or an organic compound having a functional group may be introduced into the polymer skeleton. transparency·
When the appearance such as glossiness is important, an acrylic or polyester polymer is suitable. Also, the amount of the new aqueous functional groups such as carboxyl group and hydroxyl group in the polymer is important. If the amount of the new aqueous group is too large, the electrodeposition layer is not sufficiently insolubilized, resulting in a nonuniform film. The water solubility at the time becomes insufficient.

As a polymer solvent, water is a main component, but isopropanol, n-butyl alcohol, t-butyl alcohol,
A new aqueous solvent such as methyl cellosolve, ethyl cellosolve, isopropyl cellosolve, butyl cellosolve, diethylene glycol methyl ether, diethylene diglycol ethyl ether, or diacetone alcohol may be included as a polymer polymerization solvent. The type and amount of the new aqueous solvent contained also greatly affect the film pressure and the uniformity of the electrodeposited layer.

In the electrodeposition coating, bath conditions and electrodeposition conditions are important factors in addition to the bath composition. For example, solid content in bath, P
H, specific resistance, degree of neutralization, dye / resin ratio, and applied voltage, time, bath temperature, pole ratio, distance between poles, and the like. Once the above-mentioned items are set and the appropriate conditions are grasped, it is a matter of management.

However, in order to obtain a high-definition multicolor surface colored body as in the present invention and to obtain an electrodeposited phase having a uniform film thickness and hue in a complex-shaped patterned conductor, various measures are required.

In general, in electrodeposition coating, the current density at the projections and the outer periphery of the object to be coated at the time of electrodeposition tends to be higher, and the thickness of this portion tends to be larger than the other portions. This phenomenon is the same in both anionic electrodeposition and cationic electrodeposition (the above polymer electrodeposition method is described in detail in Japanese Patent Application No. 58-099017).

The steps for forming a plurality of colored layers by the electrodeposition method as described above are roughly as follows. Adhesion of power supply material to glass substrate → electrodeposition → cleaning → removal of power supply material →
Thermosetting → Repeating the following.

[Problems to be solved by the invention]

As described above, when electrodeposition is performed using the electrodeposited substrate having the mosaic pattern shown in FIG. 3, abnormal electrodeposition frequently occurs at the electrodeposition pattern corners A ', B', C ', and D'. .
This abnormal phenomenon is caused by forming a desired colored layer on the energized surface electrode when performing electrodeposition using an electrodeposited substrate for obtaining a colored layer of a plurality of colors, the outer peripheral portions A ′, B ′, and C ′ of the electrodeposited pattern. , D ', the non-energized electrode portion is also colored. The abnormal electrodeposition on the non-energized electrode portion (hereinafter referred to as bipolar) is more likely to occur as the applied voltage at the time of electrodeposition is higher, the bipolar generation area is larger, and the electrodeposition pattern is finer. know.

For example, when red is electrodeposited in the first color using an electrodeposited substrate on which a plurality of colored layers are formed, the first electrode is also applied to a part of adjacent electrodes.
The color red is slightly but colored, and the bipolar part becomes an insulating layer in the subsequent electrodeposition and is not electrodeposited,
Alternatively, there is a problem that a color mixture layer with the second color is formed (see FIG. 4).

Although the generation rate of the bipolar varies depending on the pattern shape and the electrode material, it has been a serious problem in the production of the multicolored surface colored body.

[Means for solving the problem]

The cause of the bipolar, as described above, during electrodeposition,
The current density at the outer peripheral portion of the electrodeposition pattern is increased as compared with other portions. In particular, when the electrodeposition pattern is mosaic, the line length of the electrodeposition pattern is not constant and is mixed in a short and long length.
Since the line resistance of D ') is minimized, the current density becomes a portion showing a maximum value on the contrary, and the bipolar is most likely to occur and the region becomes wide.

Therefore, in order to prevent bipolar due to the maximum current density, it is possible to examine and improve the above-mentioned bath conditions and electrodeposition conditions in various ways, but the conditions for this are the shape, size, It is very complicated because it differs depending on the density and the like, and is not suitable as a practical improvement method.

Therefore, by providing a dummy electrode that does not directly function as a display pixel near the electrodeposition pattern where the current density becomes relatively large and performing electrodeposition simultaneously with the display pixel, the current density is reduced and bipolar does not occur. Was found. In principle, a part of the electrodeposition pattern in which the current density is only partially increased is eliminated, and a patterning design is introduced so that the current density is substantially the same in the entire area of the electrodeposition pattern.

As shown in FIG. 1 (a), the dummy electrodes are provided with solid electrodes with a certain area at the four corners. The solid electrode and the electrodeposited terminal of the first color are electrically connected,
The electrode pattern and the solid electrode are electrodeposited simultaneously. This sufficiently contributes to prevention of bipolar generation. Here, the electrodeposition terminal and the corresponding solid electrode may be patterned in advance so as to be electrically connected by a conductive pattern. If there is room in the outer periphery of the electrodeposition pattern, dummy electrodes may be provided on the entire periphery as shown in FIG. 1 (c). However, it goes without saying that the dummy electrode in this case is restricted to electrodeposition of the first color.

In the case of forming a colored layer by electrodeposition of n colors, it is apparent that the number of dummy electrodes required is n-1 in principle because the electrodeposition of the last colored layer is unnecessary in principle. However, empirically, when performing three-color electrodeposition, bipolar may not occur in the first color electrodeposition, and bipolar may occur only in the second color electrodeposition (depending on the electrodeposition pattern). In this case, only one dummy electrode of the second color needs to be provided. Therefore, it is required that the number of dummy electrodes be equal to or less than n-1 with respect to the number n of electrodes.

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

Example 1 As shown in FIG. 1 (a), four corners A, B, C, and D of an electrodeposited substrate having a mosaic pattern for three colors
A dummy electrode for a few colors was provided, and electrodeposition was performed in the order of red → blue → green. Electrodeposition conditions: bath temperature 30 ° C, electrode separation 10cm, voltage: red 30V, blue 70V, green 65V. A surface coloring was produced. The film thickness is 1.2 microns red,
The thickness was 1.3 μm for blue and 1.3 μm for green, and the variation in film thickness was within ± 10%. Further, both the hue and the corner color had a completely uniform appearance.

Example 2 As shown in FIG. 1 (b), dummy electrodes were formed on an electrodeposited substrate having a mosaic pattern for three colors, and four corners A, B, C, and D were used for the second color. Only provided. Electrodeposition was performed in the order of green → red → blue under the same electrodeposition conditions as in Example 1. As a result, no bipolar was generated, and the same effect as in Example 1 was obtained.

Example 32 As shown in FIG. 1C, a dummy electrode is formed on an electrodeposited substrate having a mosaic pattern for three colors, the first color covers the entire outer peripheral portion, and the second color covers four corners. Only the part was provided. Electrodeposition was performed in the order of blue → green → red. Electrodeposition was performed in the same manner as in Example 1. As a result, no bipolar was generated, and the same effect as in Example 1 was obtained.

In the above embodiments, the shape and area of the dummy electrode are not particularly described, but any shape may be used as long as the current density can be reduced, and the area of the outer peripheral margin of the electrodeposition pattern is also maximized. It is apparent that the main subject matter of the present invention is to realize the reduction of the current density by utilizing the maximum current density.

[Effects of the Invention] By providing the dummy electrode on the outer peripheral portion of the electrodeposition pattern of the electrodeposited substrate as described above, it is possible to completely prevent the abnormal electrodeposition phenomenon called bipolar, and to obtain a multicolor surface colored body. Quality and manufacturing yield have improved.

Japanese Patent Application No. 59-067900 discloses that a dummy electrode is provided on the outer periphery of a multicolored colored body to make the film thickness uniform, but it is clear that the purpose and the content of the invention are completely different from those of the present invention. I want to attach it just in case.

[Brief description of the drawings]

1 (a) to 1 (c) are plan conceptual views of a mosaic electrodeposition pattern having a dummy electrode according to the present invention, and FIG.
FIG. 3 is a schematic view of a triangle pattern, FIG. 3 is a schematic view of a conventional mosaic electrodeposition pattern, and FIGS. 4 (A) and 4 (B).
3A is a conceptual view showing a bipolar phenomenon, FIG. 3A is a plan view thereof, and FIG. 3B is a sectional view taken along line XY. A, B, C, D: Electrodeposition pattern corner 1: Electrodeposited terminal of first color 2 ... Electrodeposited terminal of second color 3: Electrodeposited terminal of third color 4: Display pixel section 5 Connection part 6 Dummy electrode of first color 7 Dummy electrode of second color 8 Red color filter 9 Bipolar

Claims (2)

(57) [Claims] 1. A multicolor surface colored body in which a colored layer is formed by electrodeposition on a plurality of mosaic conductive patterns formed insulated from each other on a substrate. An electrodeposited terminal connected to the conductive pattern, and a dummy electrode electrically connected to the electrodeposited terminal at least at the time of electrodeposition, and an electrodeposited layer is formed simultaneously with the mosaic conductive pattern; A multicolor surface colored body, wherein an electrode is formed near at least one corner on the substrate. 2. The method according to claim 1, wherein the number of colors of the colored layer electrodeposited on the dummy electrode is n-1 or less with respect to the number of colors n electrodeposited on the mosaic conductive pattern. 2. The multicolor surface colored body according to 1.