JPH0218400B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for producing a multicolor pattern on a substrate, and in particular, a method for producing a multicolor pattern on a substrate, in which a fine multicolor pattern is formed by electrodepositing a polymer on a conductive layer to form a colored layer. The present invention relates to a manufacturing method for forming a product by forming a product by a process.

(Prior art) Generally, as a method for obtaining a multicolor pattern, if the substrate is made of glass, for example, a coloring method by surface diffusion of metal ions, a coloring method by printing and baking using a low melting point glass frit, or a coloring method using an organic polymer. Coloring methods are known in which a printed pattern is formed using ink containing a molecular binder by a method such as screen printing.

However, each of these methods has its advantages and disadvantages; for example, the coloring method by diffusion of metal ions maintains the flatness of the surface of the glass, but has the disadvantage that the process is complicated and that it cannot be colored with an arbitrary hue.

Also, with the printing method, it is difficult to print on glass, and the colored layer itself lacks uniformity.
Lack of transparency etc.

Furthermore, these methods have a common drawback in that they become more difficult as the pattern becomes finer and the number of colors increases, resulting in deviation from the desired pattern position.

Even when the substrate is made of a material other than glass, there are methods such as printing to obtain a multicolor pattern, but this still becomes extremely difficult as the pattern becomes finer and multicolored.

One way to obtain fine patterns is to use photolithography, but this method also has the disadvantage that it is necessary to go through a photolithography process each time a multicolor pattern is produced, making the process extremely complicated. .

Therefore, in Japanese Patent Application No. 57-233934, the present inventor patterned a conductive thin film on a substrate with an insulating surface in order to easily obtain a fine and multicolored arbitrary pattern. We proposed a method for producing multicolor patterns using a conductive thin film as an electrode and electrodepositing insulation and dye as a colored layer.

However, when used in a chemically harsh environment, such as when the colored layer is repeatedly washed or immersed in chemicals for a long time, it is not possible to simply coexist the polymer and the dye in the colored layer. There is a problem in that so-called color fading occurs in which the colored layer is detached from the colored layer.

(Objective of the Invention) Therefore, in order to obtain a chemically robust multicolored pattern by electrodeposition, the present invention involves chemically bonding a dye to a polymer and electrodepositing it, or electrodepositing a dye and a polymer. After that, it provides a method for chemically bonding the dye and the polymer in the colored layer. According to this method, a chemically robust multicolor pattern can be obtained without sacrificing the simplicity of electrodeposition.

(Structure of the Invention) Hereinafter, a method of forming a colored layer by electrodeposition and a method of chemically bonding a dye and a polymer will be described. Generally, one method for electrodepositing a polymer on an electrode is to insolubilize and precipitate the polymer on the electrode from a polymer solution. One example of this is a method known industrially as electrodeposition painting, in which a pigment is dispersed in an aqueous polymer solution, a metal is immersed, and used as an electrode to electrodeposit a colored layer on the metal. Used for coating, etc. 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. to make it water-soluble. Then, when the electrode is immersed in an aqueous solution of the water-soluble polymer and a voltage is applied, the carboxyl anions dissociated in the aqueous solution migrate electrophoretically and react with protons generated by water electrolysis on the electrode. Polymers become insolubilized and precipitate. That is, the reaction shown in the following formula occurs on the anode, and polymer precipitation is observed, which is called anionic electrodeposition.

In addition, a basic group (e.g. polyamine) is added to the hydrophilic group.
If the polymer is neutralized and water-solubilized using an acid, the polymer will be deposited on the cathode, which is called cationic electrodeposition.

If the electrodeposited polymer is electrically insulating, the current decreases as the electrode is coated with the polymer, and further coating can be prevented, so an increase in film thickness cannot be expected. Due to the bubbles of oxygen generated by decomposition, complete coverage is avoided and a certain degree of film thickness can be obtained. Furthermore, the obtained polymer film becomes a uniform film with low water content due to the effect of electroosmosis.

Examples of such polymers for 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, A copolymer of acrylic acid or methacrylic acid and its ester is used, and depending on the characteristics of the electrodeposited film, other polymers or organic compounds having functional groups may be introduced into the skeleton.
These polymers are arbitrarily selected depending on the desired properties of the colored layer. For example, when it is desired to make the colored layer transparent, acrylic-based or oil-free polyester-based polymers are suitable. Methods for producing polymers for electrodeposition differ depending on the type of polymer, but a method for producing acrylic polymers will be described as an example. Acrylic polymers are produced by radical copolymerization of acrylic acid or methacrylic acid having a carboxyl group and an acrylic ester or methacrylic ester having a neutral group. In this case, the ratio of carboxyl groups to neutral groups is important; if there are too many carboxyl groups, the electrodeposited polymer will not be sufficiently insolubilized, and if there are too few carboxyl groups, water solubility during neutralization will be insufficient. Become. Additionally, OH groups may be introduced to increase water solubility. Once the monomer composition is determined, polymerization is usually carried out using isoprobanol, n-butyl alcohol, t-butyl alcohol, methyl cellosolve, ethyl cellosolve, isopropyl cellosolve, butyl cellosolve, diethylene alcohol methyl ether, diethylene glycol ethyl ether, diacetone alcohol, etc. Solution polymerization is carried out using a common radical polymerization initiator in a hydrophilic solvent.

Since the polymer film obtained by electrodeposition cannot be used as a colored layer as it is, a means for coloring it is required. A common method is to disperse pigments in an aqueous polymer solution for electrodeposition. The pigments used include titanium oxide, precipitated barium sulfate, talc, asbestin, china clay, red iron oxide, horizontal iron oxide, strontium chromate, basic lead silichromate, phthalocyanine blue, phthalocyanine green, Hansa yellow, carbon black, etc. The pigment is electrically charged in an aqueous polymer solution, and the polymer is adsorbed to its surface, electrophoresed together with the polymer, and incorporated into the electrodeposited film.

However, coloring with such pigments generally lacks transparency and is often inappropriate when forming a multicolor pattern on a transparent substrate such as glass and displaying colors by transmitting the pattern.

Therefore, the present inventor has disclosed in Japanese Patent Application No. 58-099017 that an electrodeposited colored film with good transparency can be obtained by using a dye that is insoluble or poorly soluble in water as a pigment. However, there are dyes that are insoluble in water but have high solubility in various organic solvents. In such a case, when the colored layer is immersed in an organic solvent, discoloration, that is, a phenomenon in which the dye gradually dissolves into the organic solvent, is unavoidable. Therefore, with the aim of easily obtaining multicolor patterns that can be used in special environments such as organic solvents, in the present invention, in order to further increase the chemical robustness of multicolor patterns produced by electrodeposition, polymer The researchers discovered a method of chemically bonding the pigment and the pigment to form a stronger colored layer.

Currently, reactive dyes are commercially available as dyes that chemically bond with polymeric fibers, and the fastness of the dyed products is highly evaluated. Most commercially available reactive dyes have ionically dissociable groups such as sodium sulfonate to impart water solubility, and if you add them to an electrodeposition bath and try to electrodeposit them in the conventional manner, they will not mix with the polymer. The significant difference in electrophoretic speed makes control of film thickness and its uniformity extremely difficult. In other words, it is preferable that the dye used for electrodeposition has a weak charge so that it electrophoresizes at the same speed as the polymer.
For this purpose, the first method is to chemically bond a reactive dye and a polymer through a reaction, thereby creating a colored polymer for electrodeposition in advance, and then subjecting it to electrodeposition to combine the dye and polymer as described above. We have found that this solves the problem caused by different electrophoresis speeds.

Generally, reactive dyes include monochlorotriazinyl group, dichlorotriazinyl group, vinylsulfonyl group,
It has active groups such as chlorpyrimidyl group, chlorpyridazonyl group, alkyl sulfate group, chlorquinoxalinyl group, and acrylamide group, and is suitable for cellulose fibers.
It undergoes a chemical reaction with OH groups and amino groups in nylon, wool, silk, etc., and is dyed. For example, the reaction with OH group under alkaline conditions is as follows.

In the case of monochlorotriazinyl group In the case of vinylsulfonyl group In case of alkyl sulfate group In this way, reactive dyes are fixed to polymers through covalent bonds, resulting in high fastness. By applying this to a polymer for electrodeposition, the dye and polymer are bonded together during electrodeposition, making it possible to form a colored layer together. Moreover, the polymer for electrodeposition generally contains a considerable amount of OH groups that can become reactive groups with reactive dyes for the purpose of improving water solubility, making it easy to carry out the present invention.

Another method using reactive dyes is to remove the ionic dissociative group of the dye and weaken the charge to a level that matches the electrophoretic speed of the polymer. In this case, one method is to replace the sodium sulfonate group in the dye molecule with a weakly dissociable functional group such as a carboxyl group, OH group, or amino group. The simplest method is to ion-exchange the sodium of sodium sulfonate in the dye molecule with calcium or barium to make it poorly soluble in water. This can be obtained as a precipitate by adding calcium salt or barium salt to an aqueous dye solution. A colored electrodeposited film can be obtained by dispersing this reactive dye, which has become sparingly soluble in water, in water together with a polymer and electrodepositing it. The bond between the polymer and the reactive dye is completed by subsequent heat treatment, resulting in a solid colored layer.

(Example) The present invention will be specifically explained below using Examples.

Example 1 Acid value 50, with trimellitic anhydride and trimethylolpropane as main monomers as polymers,
A polyester anion electrodeposition resin with a hydroxyl value of 70 was used. It is thought that this resin partially has the structure shown below.

It has a carboxyl group that is necessary to exhibit electrostatic properties and an OH group that improves water solubility. This resin becomes water-soluble by neutralizing the carboxyl group with an alkali or amine, and exhibits anionic electrodeposition property by itself. The method of reacting with a reactive dye is to add a red reactive dye (trade name) having a monochlorotriazinyl group to the aqueous resin solution made alkaline.
Cibacron (manufactured by Ciba Geigy) and heated to a temperature of 80°C. In this case, care must be taken because if the temperature is too high, hydrolysis of the polyester resin will occur. After reacting for 1 to 2 hours, it is cooled and acidified by adding sulfuric acid, etc., and the dyed resin precipitates out. In order to remove unreacted dye and impurity ions from this precipitated resin, acid washing and water washing are repeated. Dissolve the thoroughly washed resin in ethyl cellosolve to make a solution with a resin concentration of 70%, and adjust the pH to 7.5 to 8.0 with amine. To impart thermosetting properties to this solution, a water-soluble melamine resin is added to the polyester:melamine ratio=7:
3 and diluted with water to a total resin concentration of 10% to prepare an electrodeposition bath.

A glass substrate 2 on which transparent conductive films 1 and 1' made of tin oxide have been patterned in stripes with a width of 200 μm as shown in the figure is immersed together with a counter electrode in this electrodeposition bath, and the transparent conductive film 1 is used as an anode. , a voltage was applied with the counter electrode as the cathode. When the glass substrate 2 was pulled up and washed with water, a highly transparent colored film was formed on the transparent conductive film 1 to which a voltage was applied, and no precipitates were found on the transparent conductive film 1' to which no voltage was applied. I couldn't see it. The electrodeposited colored film is a mixture of colored polyester resin and melamine resin, which undergoes a crosslinking reaction when heated to around 180°C and hardens to form a strong film.

Similarly, an electrodeposition bath made of a polyester resin reacted with a blue reactive dye was prepared, and a voltage was applied to the transparent conductive film 1' to perform electrodeposition, washing with water, and hardening. A multicolor pattern was manufactured in which blue 3' was formed as a colored layer on 3 and 1'.

The multicolor pattern thus produced did not lose its color at all even after being immersed in an organic solvent such as ethanol and subjected to ultrasonic cleaning or boiling.

The reaction between the polyester and the reactive dye in this example seems to be a reaction between the carboxyl group or OH group in the polyester and the monochlorotriazyl group of the reactive dye, but there was no significant change in the electrodeposition properties of the polyester after the reaction. Since there is no reaction with the carboxyl group, it seems that the reaction with the carboxyl group is small.

Example 2 The reactive dye in Example 1 was replaced with a reactive dye having a phosphonic acid group (trade name: Procion T).
manufactured by Imperial Chemical Industries Ltd.).
Since this dye is reactive under neutral or acidic conditions, the polyester resin in Example 1 is added to a neutralized dye aqueous solution, and the reaction is carried out by heating. In this case, since the reaction is carried out in a neutral environment, decomposition of the polyester is difficult to occur and the reaction can be carried out at a higher temperature.

Hereinafter, a multicolor pattern was produced in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

Example 3 The reactive dye in Example 1 was replaced with a reactive dye having a vinylsulfonyl group (trade name: Sumifix manufactured by Sumitomo Chemical), and a multicolor pattern was produced in the same manner as in Example 1. It worked.

Example 4 The reactive dye in Example 1 was replaced with a reactive dye having a chlorpyrimidinyl group (trade name: Drimarene).
Sandoz Ltd.), and a multicolor pattern was produced in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

Example 5 The reactive dye in Example 1 was replaced with a reactive dye having a chlorpyridazonyl group (trade name: Primazine).
(manufactured by P BAST), and a multicolor pattern was produced in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

Example 6 When the reactive dye in Example 1 was replaced with a reactive dye having an alkyl sulfate group, for example, color index number CIReactive Blue19, and a multicolor pattern was produced in the same manner as in Example 1, the same effect as in Example 1 was obtained. can get.

Example 7 The reactive dye in Example 1 was replaced with a reactive dye having a chloroquinoxalinyl group (trade name: Levafix).
When a multicolor pattern was produced in the same manner as in Example 1, the same effect as in Example 1 was obtained.

Example 8 As the polymer in Example 1, an acrylic anion electrodeposition resin having an acid value of 50 and a hydroxyl value of 40 and containing acrylic acid and hydroxyethyl methacrylate as main monomers was used. It is thought that this resin partially has the following structure, Again, it contains carboxyl groups and OH groups, and as with polyester, reactive dyes can be chemically bonded and then electrodeposited.

Hereinafter, a multicolor pattern was produced in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

Example 9 When a reactive dye having a dichlorotriazinyl group (trade name: Mikacion, manufactured by Mitsubishi Kasei) is dissolved in water and then calcium chloride is added, the dye becomes insoluble in water and precipitation of the dye occurs. This insolubilized dye is filtered, separated, thoroughly washed with water, and dried. This pigment is applied to a polyester-melamine mixed anionic electrodeposition paint (product name: Esbia ED-3000 manufactured by Shinto Paints):
Mix and thoroughly disperse the resin at a ratio of 2:8.
This mixture is made into an aqueous solution with a resin concentration of 10% and used as an electrodeposition bath.

Hereinafter, a multicolor pattern was produced using this electrodeposition bath in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

In the case of this example, the bonding between the dye and the polymer is thought to occur during the curing of the polyester and melamine, and in addition to the carboxyl groups and OH groups in the polyester, it also reacts with the methylol groups in the melamine resin. there is a possibility.

Example 10 Reactive dye with acrylamide group (trade name
When calcium chloride is added after dissolving Lanasol (manufactured by Ciba Gaiki Co., Ltd.) in water, the dye becomes insoluble in water and precipitation of the dye occurs. This insolubilized dye is filtered, separated, thoroughly washed with water, and dried. This pigment is applied to acrylamide cationic electrodeposition paint (product name: Esbia).
ED-5000 manufactured by Shinto Paint Co., Ltd.) at a ratio of pigment: resin = 2:8 and thoroughly dispersed. This mixture is made into an insoluble material with a resin concentration of 10% and used as an electrodeposition bath.

Hereinafter, when the polarity of the applied voltage during electrodeposition in Example 1 was reversed and the rest was carried out in the same manner as in Example 1, a multicolor pattern was produced using this electrodeposition bath, and the same effect as in Example 1 was obtained. Ta. In the case of this example, the reaction in the colored layer appears to be a reaction between the dye and acrylamide due to heating.

(Effects of the Invention) As specifically described in the examples, the present invention utilizes electrodeposition to easily obtain a fine multicolor pattern, and the accuracy of the multicolor pattern is due to the fact that the colored layer is not on the conductive layer. It is much higher than the characteristic that it is not electrodeposited, and changing the color is extremely simple as it only needs to be electrodeposited using an electrodeposition bath with a different color tone. Moreover, by chemically bonding the dye and the polymer, an extremely chemically robust colored layer can be obtained without sacrificing any of its simplicity.

[Brief explanation of drawings]

FIG. 1 is a plan view of a multicolor pattern using the method for manufacturing a multicolor pattern according to the present invention, and FIG. 2 is a sectional view of a multicolor pattern using the method for manufacturing a multicolor pattern according to the present invention. 1, 1'...Transparent conductor layer, 2...Glass substrate,
3,3'...Colored layer.

Claims (1)

[Claims] 1. A method for manufacturing a pattern, which comprises forming a plurality of conductive layers having arbitrary patterns on a substrate whose surface is insulating, and then forming a colored layer on the conductive layers by electrodeposition. In this step, electrodeposition is performed in an electrodeposition bath containing a polymer and a dye, in which the dye electrophores at approximately the same speed as the polymer, and the polymer and dye are chemically bonded in the colored layer. A method for manufacturing a pattern characterized by being combined. 2. The pattern manufacturing method according to claim 1, wherein the colored layer is formed by electrodeposition after chemically bonding a dye to a polymer. 3. The pattern manufacturing method according to claim 1, wherein the colored layer is formed by electrodepositing a polymer and a dye and then chemically bonding the polymer and the dye. 4. The colored layer contains a phosphonic acid group, a monochlorotriazinyl group, a dichlorotriazinyl group, a vinylsulfonyl group, a chlorpyrimidinyl group, a chlorpyridazonyl group, an alkyl sulfate group, a chloroquinoxalinyl group, or an acrylamide group. at least 1 of them
A method for producing a pattern according to claim 2 or claim 3, characterized in that a dye having one as a reactive group and a polymer are chemically bonded via the reactive group. . 5 The polymer forming the colored layer is a water-soluble or water-dispersible acrylic resin, a polyester resin,
The method for manufacturing a pattern according to claim 4, characterized in that the pattern contains at least one of melamine resins as a main component. 6. The pattern manufacturing method according to claim 1, wherein the substrate whose surface is insulating is transparent. 7. The pattern manufacturing method according to claim 1, wherein the conductor layer is transparent.