JPH10330994A - Patterned and colored body of aluminum material and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum material having a colored oxide film with the fine pattern of the characters, graphic, etc., formed thereon excellent in durability and to provide its production method. SOLUTION: The patterned and colored body of aluminum material is produced as follows. Namely, an anodized aluminum material 1 is dipped in a pigment dispersion to migrate and deposit a pigment grain 10 in the pore 3 of an anodic oxide film 2 by electrophoresis and colored. A masking pattern 4 is printed on the surface of the colored oxide film. The colored oxide film at the unmasked part is decolored, and then the masking pattern is removed. A coloration stage can be added after the decoloration stage. In this case, a pigment grain 11 is deposited in the pore of the anodic oxide film at the decolored part by electrophoresis or electrolytic coloration is applied and the anodic oxide film at the decolored part can be recolored by another color, and the process can be repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a patterned colored body of an aluminum material and a method for producing the same, and more particularly, to a method of forming a colored substance such as an organic pigment or an inorganic pigment deeply into pores of an anodic oxide film of an aluminum material. The present invention relates to a patterning surface treatment method for forming a colored oxide film of various robust and vivid patterns by depositing or filling in a pattern. In this specification, the aluminum material is a general term for aluminum and aluminum alloy.

[0002]

2. Description of the Related Art Conventionally, a method of putting a colored pattern on an anodic oxide film of an aluminum material has been put to practical use.
(1) A method of attaching a sticker depicting a pattern applied to lunch boxes, pots, kettles, etc. (2) Screen printing method used for sign boards, name plates, etc., (3) Anodized film surface To the photosensitive emulsion,
After exposing through a photomask, a method of developing and drawing a predetermined pattern, (4) a method of attaching a sheet cut out by a cutting plotter to a signboard or the like are known.

[0003]

However, in the case of the sticking method (1), the seal is easily damaged.
In addition, there is a problem that there is no durability, so that applicable products are limited. Further, in the case of the screen printing method (2), since the printing ink is merely attached to the surface of the anodic oxide film, the ink easily peels off, the pattern is easily erased, and the durability is poor. . on the other hand,
In the case of the photographic method (3), since the pattern is drawn with a photographic emulsion, there is a problem that the pattern is easily faded by sunlight (ultraviolet rays). Further, in the case of the method (4), since a sheet is cut out by a cutting plotter to draw a pattern, there is a problem that a small character or a fine pattern cannot be drawn.

[0004] The present invention has been made in view of the above-mentioned problems of the prior art, and its basic object is to provide:
Colored substances such as pigments are deposited or filled deep into the pores of the porous anodic oxide film of aluminum material.They show sufficient light resistance and durability even when used outdoors, and are robust without discoloration or fading. It is an object of the present invention to provide a patterned colored body of an aluminum material having a colored oxide film having a colorful desired pattern and a method for producing the same. It is a further object of the present invention to provide an aluminum material having a colored pattern with excellent durability of fine patterns such as characters and figures, and a method of manufacturing the same.

[0005]

According to a first aspect of the present invention, an aluminum oxide anodic oxide film is masked in a predetermined pattern and then pigmented by electrophoresis. A method for producing a patterned colored body of an aluminum material is provided. The first aspect,
(A) a step of printing a masking pattern on the surface of the anodic oxide film of the anodized aluminum material; and (b) dipping the aluminum material having the masking pattern formed in the pigment dispersion to form a thinner anodic oxide film on the non-masked portion. It is characterized by including a step of coloring the pigment particles by electrophoresis in the holes by electrophoresis, and a step (c) of removing the masking pattern.

In a second aspect, (a) a step of printing a masking pattern on the surface of the anodized film of anodized aluminum material, and (b-1) a step of printing the aluminum material having the masked pattern in a pigment dispersion. Immersion in the pores of the anodic oxide film of the non-masking portion, electrophoresis to cause the pigment particles to migrate and precipitate by coloring,
(C) a step of removing the masking pattern, and (b-2) immersing the aluminum material from which the masking pattern has been removed in another pigment dispersion to form pores of the anodic oxide film in the masking pattern-removed portion and the non-masking portion. Electrophoretic migration of pigment particles during the electrophoresis or electrolytic coloring of the aluminum material to include a step of coloring the anodized film of the masking pattern removed portion and the non-masking portion to different colors. Features.

According to a second aspect of the present invention, there is provided a method for producing a patterned colored body of an aluminum material, which comprises a combination of pigment coloring, masking and partial decolorization. In the first embodiment, (A) a step of immersing an anodized aluminum material in a pigment dispersion, and electrophoretically depositing and depositing pigment particles in pores of the anodized film by electrophoresis, thereby coloring ( B) a step of printing a masking pattern on the surface of the colored oxide film, (C) a step of decolorizing the colored oxide film in a non-masked portion, and (D) a step of removing the masking pattern.

In a second embodiment, (A-1) an anodized aluminum material is immersed in a pigment dispersion, and pigment particles are electrophoretically deposited in pores of the anodized film by electrophoresis. (B) a step of printing a masking pattern on the surface of the colored oxide film, (C) a step of decolorizing the colored oxide film in the non-masked portion, and (A-2) separating the partially decolorized aluminum material. The pigment particles are immersed in the pigment dispersion of the above, and the pigment particles are migrated and deposited by electrophoresis into the pores of the anodized film in the decolorized portion, or the decolorized aluminum material is subjected to electrolytic coloring treatment, and the The method further includes a step of recoloring the anodic oxide film to another color, and a step of (D) removing the masking pattern.

In a third embodiment, (A-1) an anodized aluminum material is immersed in a pigment dispersion, and pigment particles are electrophoresed and deposited in the pores of the anodized film by electrophoresis. Coloring step, (B-1) the above (A-1)
A step of printing a masking pattern on the surface of the colored oxide film obtained in the step, (C-1) a step of decolorizing the colored oxide film in the non-masked portion, (D-1) a step of removing the masking pattern, (A- 2) The aluminum material partially decolorized in the step (C-1) was immersed in another pigment dispersion, and pigment particles were electrophoresed and deposited in the pores of the anodic oxide film by electrophoresis to be decolorized. (B-2) a step of printing a masking pattern on the surface of the colored oxide film obtained in the above step (A-2), −
2) a step of decolorizing the colored oxide film of the non-masking portion;
(D-2) a step of removing the masking pattern formed in the step (B-2), and (A-3) a step of removing the (C-
2) The aluminum material partially decolorized in the step is immersed in another pigment dispersion, and pigment particles are electrophoresed and deposited in the pores of the anodic oxide film by electrophoresis to remove the decolored portion and the masking pattern. The method is characterized in that the method further includes a step of recoloring the anodic oxide film of the portion to another color.

In the third aspect, the above (A-
Step 2), step (B-2), step (C-2) and (D-
2) By repeating the steps, a multicolor pattern of three or more colors can be obtained. (B-3) a step of printing a masking pattern on the surface of the colored oxide film obtained in the step (A-3) after the recoloring in the step (A-3);
(C-3) a step of decolorizing the colored oxide film of the non-masking portion; and (D-3) a step of removing the masking pattern formed in the above (B-3) step, and the background portion is formed as an anode. The ground color (silver color) of the oxide film can also be used.

In the second and third embodiments of the second aspect of the present invention, after decolorization, (A-2)
Prior to the recoloring step (A-3), it is preferable to subject the aluminum material to anodic oxidation treatment again. According to the method according to any of the aspects and embodiments of the present invention as described above, a coloring substance such as a pigment is deposited or filled from the opening of the pores of the porous anodic oxide film formed on the aluminum material to the bottom of the pores. It has excellent properties such as light resistance, durability, and corrosion resistance.
A colored body of an aluminum material which is not faded and is patterned in a robust and colorful desired pattern can be obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention utilizes a pore of an anodic oxide film of an aluminum material to provide a portion for depositing / filling a coloring substance such as a pigment and a portion for not depositing / filling in the pore. The present invention provides a surface treatment technology of an aluminum material for performing patterning by using a printing technique to block (mask) pores of an anodic oxide film and color a non-masked portion according to a desired pattern. Alternatively, the entire surface of the anodic oxide film is colored in advance, and after the masking pattern is printed, the non-masked portion of the colored oxide film is decolorized. Further, as a basic coloring method of the anodized film, a so-called electrophoretic coloring method in which a pigment is electrophoresed and deposited in pores of the anodized film in a pigment dispersion by an electrophoretic method.

By employing such an electrophoretic coloring method in combination with the above-described patterning method, it is possible to form a robust and colorful pattern without discoloration or fading. In addition, since the electrophoretic coloring method of the pigment is adopted for coloring, it is possible to perform patterning in combination with the above-described decolorization. In other words, in the case of the electrophoretic coloring method using a pigment, immediately after the coloring treatment and when not exposed to a high temperature,
With a solution in which the dispersant of the pigment dispersion is dissolved, generally an aqueous alkaline solution, the pigment coated or adhered with such a dispersant can be extracted from the pores of the anodic oxide film and decolorized. Therefore, patterning can be performed using this characteristic.

As described above, the method of the present invention comprises forming a masking pattern by a printing technique and decolorizing a non-masked portion by electrophoretic coloring or, if pre-electrophoretic colored, a colored oxide film of the non-masked portion. The basic feature is that a colored pattern is formed on the anodic oxide film of the aluminum material by the combination of the above. Since the masking pattern is formed by the printing technique in this manner, an oxide film of a fine pattern of characters, figures, etc. can be formed on the surface of the aluminum material, and the electrophoretic coloring method is used for coloring, and the anodic oxide film is formed. Pigment particles are deposited deep inside the pores, so there is no dropping of the pigment particles, and there is no change or fading due to the pigment particles. It becomes a vivid colored pattern with excellent properties.

Further, in the case of the combination of masking pattern formation and electrophoretic coloring according to the first aspect of the present invention, the colored oxide film in the non-masked portion and the ground color of the anodic oxide film in the masked portion after the masking pattern is peeled off. A pattern consisting of the following is obtained. By performing coloring (electrophoretic coloring or electrolytic coloring) again on the masked portion, a two-colored pattern can be formed. Further, a step of coloring after forming the masking pattern again Alternatively, it is also possible to form a multicolor pattern of three or more colors depending on the method of repeating them in combination. On the other hand, in the case of the combination of electrophoretic coloring, masking pattern formation, and decolorization on the second side, after the masking pattern is peeled off, it consists of the color of the colored oxide film of the masked part and the color of the decolorized non-masked oxide film. A pattern can be obtained, but by appropriately combining and repeating such operations, a multicolor pattern of not only two colors but also three or more colors can be formed.

Hereinafter, various embodiments of the method of the present invention will be described with reference to the accompanying drawings. 1 and 2 show a manufacturing process of a patterned colored body of an aluminum material according to the first aspect of the present invention, FIG. 1 is a schematic diagram of a change in a cross-sectional structure of an anodized film, and FIG. 2 is a flowchart of each process. ing. First, as shown in FIG. 1A, a masking pattern 4 is printed on the surface of the anodic oxide film 2 of the anodized aluminum material 1 (masking pattern printing step). In addition, in order to obtain a robust and vivid aluminum colored oxide film with excellent properties such as light resistance, weather resistance and heat resistance in the electrophoretic coloring step described below, without detachment of the pigment, the pigment must be porous. It is necessary that the pores 3 of the anodic oxide film be deposited or filled as deeply as possible. Therefore, the fineness of the pigment particles and the dispersing of the pigment particles in water and the formation of the pores of the anodic oxide film capable of depositing or filling the pigment are performed. And adjustment (pore diameter enlargement treatment) is required.

As the porous anodic oxide film on which inorganic pigments such as organic pigments and carbon black are deposited and filled, pores larger than the pore diameter of a normal anodic oxide film, for example, 30
A porous anodic oxide film having pores of about 200 to 200 nm (300 to 2000), preferably about 50 to 200 nm is desirable. The porous anodic oxide film having such large pores can be prepared by various conventionally known methods. Further, the method of forming an anodic oxide film already proposed by the present applicant in Japanese Patent Application Laid-Open No. 5-93296 can be suitably used, and the method is roughly classified into the following two methods. (1) Mineral acid or organic acid such as sulfuric acid,
High voltage (for example, DC120 to DC1) in one or more kinds of aqueous acid solutions such as phosphoric acid, oxalic acid, malonic acid, and maleic acid
Anodizing at 200 V, preferably 150 to 200 V) to form a porous anodic oxide film having pores larger than a normal pore diameter of about 50 nm or less on the surface of the aluminum material; After anodic oxidation in an aqueous solution of one or more of a mineral acid or an organic acid to form a porous anodic oxide film on the surface of the aluminum material, one of phosphoric acid, sulfuric acid, oxalic acid, and sulfamic acid is formed. A method of performing a process of immersing in a kind or two or more kinds of acid aqueous solutions or a process of repeating the immersion and alternating current electrolysis in a fixed cycle to perform a process of expanding the pore diameter of the pores of the porous anodic oxide film.

A masking pattern 4 is printed on the anodic oxide film 2 of the aluminum material 1 formed by such an anodic oxidation method. As the printing method, various printing methods such as screen printing, offset printing, gravure offset printing, and humbic printing (inkjet method) can be adopted. However, especially when a high-definition pattern is required, the screen printing method and the humbic printing method are preferable. . As the masking agent, any material can be used as long as it exhibits a masking function without peeling off in the electrophoretic coloring step in the pigment dispersion and can be easily peeled off by a solvent, and is not limited to a specific substance. For example, oils and fats such as silicone oil and room temperature drying type resin paints such as acrylic resin can be suitably used. In the case of the humbic printing method, a hydrophobic agent such as a silicone fluorine compound (a liquid that modifies the coated surface to be hydrophobic) can be suitably used.

Next, the aluminum material 1 having the masking pattern 4 printed on the surface of the anodic oxide film 2 as described above is immersed in a pigment dispersion, and electrophoresis is performed as shown in FIG.
As shown in (1), the pigment 10 is electrophoresed and deposited in the pores 3 of the anodic oxide film 2 in the non-masking portion (electrophoretic coloring step). As the pigment dispersion, a pigment dispersion of an organic pigment or an inorganic pigment having a particle diameter of 3 to 150 nm is used, and as a condition of the bath of the pigment dispersion, the pigment concentration is preferably 5%.
0 g / l or less, more preferably 10 to 40 g / l, and the temperature of the bath is preferably 30 ° C. or less, more preferably 15 to 2 g / l.
The pH of the bath at 5 ° C is preferably 10 or less, more preferably 8.5 to 9.5. In the pigment dispersion adjusted to such a range, when the aluminum anodic oxide film is used as an anode and colored by electrophoresis, there is no color unevenness. Since no precipitation occurs, coloring is possible over a wide voltage range,
Further, coloring with controlled shading becomes possible.

When the concentration of the pigment in the bath is higher than 50 g / l, the pigment tends to agglomerate due to the high pigment concentration, and tends to precipitate on the surface of the anodic oxide film. Conversely, the pigment concentration is less than 10 g / l. In this case, it is difficult to make the color deeper due to the small amount of the pigment, and in each case, it is difficult to perform sufficient coloring, which is not preferable. Also, the pH of the bath
If the pH is less than 8.5, the pH is low, the surface potential of the pigment is lowered, the pigment is easily aggregated, and the pigment is easily deposited on the surface of the anodic oxide film, which is not preferable. On the other hand, when the pH exceeds 10, the alkalinity is strong, and the pigment precipitated in the pores is easily dissolved and dispersed again.

In preparing the pigment dispersion, at least one of a higher organic pigment and an inorganic pigment is used as a pigment, and an anionic polymer activator is used as a dispersant, for example, a formalin condensate of naphthalenesulfonic acid, a polystyrene sulfonate, Water-soluble resins such as polyacrylic acid salts, acrylic acid-styrene copolymers, styrene-maleic acid copolymers, polymers of α, β-ethylenic monomers such as polyvinyl alcohol and polyvinylpyrrolidone, and modified resins thereof Is used. These dispersants can be used in a proportion of 1 to 500 parts by weight, preferably about 10 to 200 parts by weight, per 100 parts by weight of the pigment. In order to improve the solubility of the resin in water, a water-soluble organic solvent such as alcohols such as ethanol, glycols such as ethylene glycol, and cellosolves such as butyl cellosolve is used in the dispersion in an amount of 50% by weight or less, preferably 30% or less.
It can be added in a proportion of not more than% by weight. Further, as a stabilizer for dissolution or dispersion of the dispersant, an alkali or various additives can be added.
Chemicals can also be added for the purpose of, for example, adjusting the amount of water.

As inorganic pigments, there are carbon black, titanium oxide, silicon oxide and the like, and their durability can be sufficiently satisfied. In particular, carbon black has a very small particle diameter, and is preferably used in the method of the present invention. Can be. As organic pigments, coloring and light resistance, weather resistance, heat resistance,
High-quality organic pigments having excellent durability such as solvent resistance can be suitably used. Those belonging to this class include condensed azo pigments, phthalocyanine pigments, and perylene pigments,
There are condensed polycyclic pigments such as perinone type, quinacridone type, thioindigo type, dioxazine type, isoindolinone type, isoindoline type, quinophthalone type and metal complex type.
In these pigment particles, generally, primary particles having a size of 10 to 500 nm are aggregated to form an aggregate, and it is preferable to disperse the aggregate to a particle size of about 3 to 150 nm.

The pigment particles can be made fine and dispersed by a sand mill, a roll mill, and a dispersant as described above.
A method of obtaining a stable aqueous dispersion by sufficiently dispersing with a dispersing machine such as a ball mill or the like, before performing a surface treatment such as plasma treatment on a pigment before dispersing with a sand mill or the like, to obtain a more excellent aqueous dispersion. Method, or further, for pigments that dissolve in concentrated sulfuric acid, etc., once dissolved in concentrated sulfuric acid, etc.,
A method of adding it to water and precipitating it as finer pigment particles can be employed alone or in combination. After dispersion, the pigment may be diluted to a desired pigment concentration, and coarse particles may be removed by filtration or the like. At this time, the lower the dispersion viscosity, the better the classification efficiency.
When the target particle size is not reached by one classification process, the classification can be repeated a plurality of times.

In order to favorably perform pigmentation by electrophoresis into the pores of the anodic oxide film, it is preferable that the pigment coated with the resin in the dispersion has a negative and larger surface charge (zeta potential). Preferably, the resin used is therefore basic. On the other hand, since the zeta potential of the pigment in the dispersion is negative, the pigment can be colored using an anodized aluminum material as the anode. If the value of the zeta potential is about -10 mV or less, the particles are suitably electrophoresed,
Precipitated and filled in the pores of the anodic oxide film of aluminum material.

In the coloring method in which fine pigments are deposited and filled in the pores of the porous anodic oxide film by electrophoresis, the coloring state of the anodic oxide film may vary depending on the conditions of the pigment dispersion. Occasionally, abnormal pigment deposition on the film surface may occur. That is, in the coloring method of the fine pigment by the electrophoresis method, the pigment is migrated into the pores of the porous anodic oxide film by applying a voltage, but if the pigment dispersion has an unnecessary conductivity, the voltage is increased. , A large amount of current unrelated to the migration of the pigment flows. Due to the current unrelated to the electrophoresis, an anodic reaction such as electrolysis of water occurs more than necessary in the pores of the anodic oxide film, and the pH in the pores of the colored film or in the vicinity of the film rapidly decreases. The pigment may be deposited unevenly in the pores of the coating, or may be easily aggregated (gelled) on the coating surface and may be easily deposited. To prevent this, the specific conductivity of the bath of the pigment dispersion is set to about 1000 μS / cm in a solution having a pigment concentration of 10 g / l so that almost no current that does not affect the electrophoresis of the pigment flows.
It is preferable to perform electrophoresis by adjusting as follows. As a result, unnecessary anodic reaction and sudden drop of pH near the film as described above are suppressed, and aggregation of the pigment can be effectively prevented.

As the electrophoresis method, a DC voltage scanning method in which a DC voltage is scanned from a low voltage to a high voltage at a constant boosting rate until a desired color is obtained, and a time until the desired color is obtained at a constant voltage is determined by electrolysis. The coloring treatment can be performed by a direct current constant voltage method or the like. The conditions of the electrophoresis treatment are the conditions of anodic oxidation,
It can be set appropriately according to the pigment dispersion used, the desired color density, and the like. For example, when electrophoresis is performed by a DC constant voltage electrolysis method, the film becomes darker as the electrophoresis voltage increases. When the migration voltage is too high, abnormal deposition of the pigment on the surface of the anodic oxide film starts. However, when the pigment concentration is high, the voltage for abnormal deposition becomes high, so that a densely colored film can be obtained in a good condition. On the other hand, at low voltage,
When the pigment concentration is high, color unevenness is observed. for that reason,
For example, when the anodic oxidation voltage is 130 V, it is generally desirable to set the voltage in the range of 110 to 140 V according to the pigment concentration. When the electrophoresis voltage is low, the anodic oxide film is colored deeper as the bath temperature increases, but no significant difference is observed at a high voltage. However, at a high voltage, if the bath temperature is high, abnormal precipitation of the pigment on the surface of the anodic oxide film tends to occur. Therefore, the bath temperature should be 30 ° C or less, preferably 1 ° C.
A range of 5 to 25C is desirable. Performing coloring under such electrophoretic processing conditions enables good coloring without color unevenness, and controls the shading of the coating over a wide voltage range without causing abnormal deposition of the pigment on the surface of the anodic oxide coating. it can.

Thereafter, the aluminum material 1 is immersed in an appropriate release agent solution to peel off the masking pattern 4, so that the pigment 10 is deposited in the pores 3 of the anodic oxide film 2 as shown in FIG. A pattern of the colored portion (non-masked portion) deposited and filled and the ground color (silver color) portion (masked portion) of the anodic oxide film 2 are obtained without being colored (masking pattern removing step). . For example, by printing a masking pattern on the surface of the anodic oxide film so that characters, figures, etc. are drawn as non-masking parts, and performing electrophoretic coloring, the background color (silver color) of the anodic oxide film is used as a background. A pattern in which colored characters, figures, and the like are drawn is obtained. As the release agent for releasing the masking pattern 4, an appropriate release agent can be selected and used according to the used masking agent. For example, when an oil or fat such as petrolatum is used as the masking agent, hexane or the like is used as the release agent. Organic solvents can be suitably used.

The aluminum material obtained by the above operation can be further subjected to a coloring treatment. For example, the aluminum material is immersed in a pigment dispersion containing a pigment 11 of another color, Similarly, by performing electrophoretic coloring, as shown in FIG. 1D, pigments 10 and 11 are deposited and filled in the pores 3 of the anodic oxide film 2 so that a certain color (two kinds of pigments 1
The pigmented portion (non-masked portion) and the pigment 11 are deposited and filled to form a portion colored to another color (a portion that has been masked), and a two-color pattern is obtained. Can be In addition, as the above-mentioned coloring treatment, other than the electrophoretic coloring, other known methods for coloring an anodized film, such as an electrolytic coloring method, can be adopted.

As the electrolytic coloring method, a conventionally known method can be appropriately adopted. For example, nickel, cobalt, chromium, copper, cadmium, titanium, manganese, molybdenum, calcium, magnesium, vanadium, iron, gold,
In a color bath containing metal salts such as nitrate, hydrochloride, oxalate, acetate, tartrate, chromate and phosphate such as silver, lead and zinc, AC electrolysis, DC cathodic electrolysis or AC / DC superposition electrolysis The electrolytic treatment is performed using the appropriate current waveform. Thereby, the masked portion of the anodic oxide film is colored in various colors such as bronze, amber, black, green, blue, and brown.

The coloring step (b) can be repeated two or more times. That is, the pigment 10 is once subjected to electrophoretic coloring to precipitate the pigment 10 in the pores 3 of the anodic oxide film 2 in the non-masking portion as shown in FIG. By immersing the pigment in the body, electrophoretically coloring in the same manner as in the above step (b), and removing the masking pattern, the pigment 1 was placed in the pores 3 of the anodic oxide film 2.
A portion (non-masking portion) colored with a certain color (mixed color of two kinds of pigments 10 and 11) by depositing and filling 0 and 11 and a ground color (silver color) of the anodic oxide film 2 without being colored (A masked portion) is obtained. Thereafter, the pigments (10, 11, and 10) are immersed in a pigment dispersion containing a pigment (12) of another color, and similarly electrophoretically colored, so that the pigments (10, 11,
12) is deposited and filled, and a portion (non-masking portion) colored with a mixture of these pigments and a pigment (1
2) is deposited and filled to form a colored portion (masked portion), and a two-color pattern is obtained.

Alternatively, a masking pattern is printed on the surface of the anodic oxide film in the state shown in FIG. 1 (c) from which the masking pattern has been removed so as to cover the non-masking portion which has already been electrophoretically colored. After printing the masking pattern so as to cover a part of the masked portion (non-colored portion), a coloring process can be performed. Such masking pattern printing and coloring processing can be performed in various modes (printing pattern, coloring color,
(Order etc.), various colored patterns can be obtained. When two or more pigments are electrophoresed and precipitated in the pores of the anodic oxide film for coloring, a mixed color of the pigments is obtained, and the hue can be appropriately adjusted depending on the electrophoretic conditions. For example, by preparing a dispersion of each of the three primary color pigments in advance and performing electrophoretic coloring using them in order, coloring can be achieved in all hues. In addition,
A dispersion having a desired hue is prepared by mixing two or more pigments, and the coloring treatment can be performed by one electrophoretic coloring. However, in this method, a pigment having a desired hue is used each time the coloring treatment is performed. It is necessary to prepare a dispersion. On the contrary,
As described above, the method of sequentially performing electrophoretic coloring using the pigment dispersions of the three primary colors can save such trouble.
This is advantageous in terms of productivity and economy. The various aspects described above also apply to the method according to the second aspect of the present invention described below.

The colored coating of the aluminum material obtained as described above can be further subjected to a sealing treatment or a clear coating, if necessary. Since the pigment precipitated in the pores of the anodic oxide film by the electrophoretic coloring is coated with a dispersant, for example, a water-soluble resin, the pigment is dissolved and redispersed with a dilute alkaline aqueous solution as described below to perform decolorization. It is possible, but such a resin, once
Exposure to acids or high temperatures no longer dissolves in dilute aqueous alkaline solutions. Therefore, by performing water vapor sealing on the pigmented aluminum material after completing each of the above steps, it is possible to reliably prevent the pigment deposited and filled in the pores of the anodic oxide film from falling off. A robust colored pattern is obtained.

FIGS. 3 and 4 show the steps of manufacturing a patterned colored body of an aluminum material according to the second aspect of the present invention. FIG. 3 is a schematic view showing the change in the cross-sectional structure of the anodic oxide film. FIG. First, as shown in FIG. 3A, the anodized aluminum material 1 is electrophoretically colored by the method described above, and the pigment 10 is electrophoresed and deposited in the pores 2 on the entire surface of the anodized film 2. (Electrophoretic coloring step). Next, a masking pattern 4 is printed on the surface of the anodic oxide film 2 of the aluminum material 1 thus electrophoretically colored as shown in FIG. 3B (masking pattern printing step). Thereafter, the aluminum material 1 thus treated is immersed in an appropriate diluted alkaline aqueous solution according to the dispersant used, for example, an alkaline aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate, sodium phosphate, amines, or the like. , The pigment was redissolved, and FIG.
As shown in (C), the colored oxide film in the non-masking portion is decolorized (non-masking portion decolorizing step).

After that, the aluminum material 1 is immersed in an appropriate release agent to release the masking pattern 4 so that the pores 3 of the anodic oxide film 2 are removed as shown in FIG.
A pattern of a colored portion (masked portion) with the pigment 10 deposited and filled therein and a ground color (silver color) portion (non-masked portion) of the decolorized anodic oxide film 2 are obtained (masking). Pattern removing step). Therefore,
For example, by printing a masking pattern on the surface of the anodic oxide film so as to draw characters, figures, etc., the background color (silver color) of the anodic oxide film is used as a background, and colored characters, figures, etc. are drawn therein. A pattern is obtained. Generally, when a colored pattern is applied, it is common to apply color only to a portion that needs to be colored. However, the coloring by the above method is a method of once coloring the entire surface of the anodic oxide film and then removing the color of a portion that does not need to be colored, which can be said to be the reverse of a general method.

On the other hand, when a two-color pattern is obtained, as shown in FIG.
The aluminum material in the state shown in (C) is immersed in, for example, a pigment dispersion containing a pigment of another color, and the decolorized portion is electrophoretically colored as shown in FIG. 3 (E). Similarly, by peeling off the masking pattern, a pigment 10 of a certain color is deposited and filled in the pores 3 of the anodic oxide film 2 as shown in FIG. The pigment 11 of a different color
Filled to produce colored parts (non-masking parts), resulting in a two-color pattern. In addition, as the above-mentioned coloring treatment, other than the electrophoretic coloring, other known methods for coloring an anodized film, such as an electrolytic coloring method, can be adopted. Alternatively, the electrophoretic coloring can be performed again on the colored oxide film in the state shown in FIG. 3E or the state shown in FIG. In this case, the non-masked portion is colored with a mixed color of the pigment 11 and another pigment from the state shown in FIG. 3E, and the masked portion is different from the pigment 10 from the state shown in FIG. Thus, a colored oxide film in which the mixed color of the pigment and the non-masking portion are colored in the mixed color of the pigment 11 and another pigment is obtained.

FIG. 5 shows the results obtained by repeating the electrophoretic coloring, masking pattern printing, decoloring, masking pattern removal, and electrophoretic coloring steps on the anodic oxide film in the state shown in FIG. 3D. FIG. 3 shows a schematic view of a change in a cross-sectional structure of a colored oxide film. That is, FIG.
The aluminum material in the state shown in FIG.
5A, the non-masked portion is colored with the pigment 11 and the masked portion is separated from the pigment 10 by electrophoretic coloring. A colored oxide film colored in a mixed color of the pigment 11 is obtained (electrophoretic coloring step). Next, a masking pattern 4 is printed on the surface of the anodized film 2 of the aluminum material 1 thus electrophoretically colored as shown in FIG. 5B-2 (masking pattern printing step). Thereafter, the aluminum material 1 thus treated is immersed in an alkaline aqueous solution, and the colored oxide film on the non-masked portion is decolorized as shown in FIG. 5C-2 (non-masking portion decoloring step). Next, as shown in FIG. 5 (D-2), after removing the masking pattern 4 (masking pattern removing step), it is immersed again in a pigment dispersion containing a pigment 12 of another color, and electrophoresed. By coloring (electrophoretic coloring step), as shown in FIG. 5 (A-3), a portion colored with pigment 12 and two types of pigment 11
And a portion colored in a mixed color of 12, and three kinds of pigments 10,
A colored oxide film having a colored pattern consisting of a portion colored in a mixed color of 11 and 12 is obtained.

FIG. 6 is a flowchart showing a process of manufacturing a multicolored colored body of an aluminum material according to the second aspect of the present invention. Since the basic principle is the same as the method shown in FIGS. 3 to 5, the change in the sectional structure of the anodic oxide film is not shown. This method uses the pigment dispersions of the three primary colors of red, yellow, and blue, and repeats the steps of electrophoretic coloring, masking pattern printing, decoloring, and masking pattern removal for each, thereby partially decolorizing. The colored portions can be recolored in a patterned manner to form a multicolored pattern.

In the decoloring step, the anodic oxide film is also slightly dissolved by the aqueous alkali solution. Therefore, if the next coloring treatment is performed as it is, the pigment particles may partially aggregate, and color unevenness may occur even in the subsequent decoloring step. In order to avoid this, it is preferable to perform the anodic oxidation treatment again after the decoloring step as shown in FIG. In FIG. 6, the masking pattern is removed after the decoloring step. This is because, for example, when vaseline is used as a masking agent, the vaseline used as the first color masking agent adheres to the surface of the second color screen printing plate when drawing the second color pattern because vaseline does not dry, and the screen The printing plate may be stained. In order to prevent this, the masking pattern must be removed when the masking becomes unnecessary after the decoloring step.
However, when a room temperature drying type resin is used as the masking agent, such a disadvantage does not occur. For example, a masking pattern removing step can be performed after the electrophoretic coloring step.

The coloring method according to the above method can be said to be exactly the reverse of the printing method. For example, when coloring a small character or pattern such as a business card by a screen printing method, a plate (screen) manufactured using a screen printing plate making technique is indispensable. This printing plate has a hole in the pattern (character) portion, and the printing ink leaks out from the hole and is printed on the printing substrate. On the other hand, in the above method, this plate is used as a tool for forming a masking agent pattern. In other words, a masking agent is attached to a portion to be printed with ink. When the anodic oxide film is masked and colored by this method, the masked portion is not colored and the unmasked portion is colored. In the case of a business card, for example, the letters on the business card remain white (the background color of the anodic oxide film remains), and the white paper is colored, giving the finish a black-and-white reversal as shown in the photograph. . Therefore, the decolorization method of the present invention can be said to be an extremely useful method for performing patterning using a plate used in a conventional printing technique so that a masking portion is colored and a non-masking portion is not colored. .

Hereinafter, the present invention will be described more specifically with reference to examples. However, it goes without saying that the present invention is not limited to the following examples.

Example 1 Aluminum material A degreased and etched according to a conventional method
1050 in a 0.3% oxalic acid bath at 20 ° C.
Perform constant voltage electrolysis at 50 V for 6 minutes, and make the film thickness 10 μm.
An anodic oxide film was formed. Next, this aluminum plate was immersed in a 5% phosphoric acid solution at 30 ° C. for 70 minutes,
The coating pore diameter was expanded. After drying, Vaseline was printed according to a predetermined pattern by screen printing. Thereafter, pigment coloring was performed in a phthalocyanine blue bath by electrophoresis. Electrophoresis conditions are 1 V / sec
To 120 V, and then held for 120 seconds. Then, the obtained aluminum material was added to hexane for 1 hour.
It was immersed for 0 minutes to dissolve and remove petrolatum. as a result,
A pattern in which the unmasked portion was colored blue was obtained. The aqueous dispersion of the pigment was prepared by dissolving 50 g of copper phthalocyanine blue in 60 ml of 98% sulfuric acid, and adding the resulting solution to 5 liter of a 0.5% aqueous sodium polyacrylate solution to precipitate phthalocyanine particles. After washing with water until the sulfate group disappeared, the pH was adjusted to 9 with sodium hydroxide, and a 0.5% aqueous sodium acrylate solution was added so that the total amount became 1 liter. To obtain an aqueous dispersion of copper phthalocyanine blue.

Example 2 An aluminum material A1050 was pretreated according to a conventional method, and then anodized in a phosphoric acid aqueous solution (30 g / liter) at 30 ° C. at a current density of 1 A / dm ² for 60 minutes. The following processes were combined with the anodic oxide film of Example 1 to carry out coloring. Electrophoretic coloring (pigment coloring): As conditions for the electrophoretic coloring, the voltage was increased to 110 V at 1 V / sec, and 1
Maintained for 20 seconds. The pigment used was phthalocyanine green for green and phthalocyanine blue for blue. The method for preparing the pigment dispersion is the same as in Example 1. Masking pattern printing: The pattern used was a plate (business card) produced by a color separation plate-making apparatus (manufactured by Riso Kagaku Kogyo Co., Ltd.). Vaseline, which was colorless and relatively easy to remove, was used instead of the printing ink. Decolorization: 0.1% of sample printed with masking pattern
A 60% aqueous solution of sodium hydroxide for 60 seconds to decolorize. These steps were combined to produce the following three types of samples. Sample 1: pretreatment → anodization → pigment coloring (green) → masking pattern printing → bleaching Sample 2: pretreatment → anodizing → masking pattern printing → pigment coloring (green) Sample 3: pretreatment → anodizing → pigment coloring ( Blue) → masking pattern printing → decolorization → AC electrolytic coloring (bronze) As a result, even small characters such as telephone numbers could be clearly read, and it was found that even small patterns could be pigmented by this method. Also, it was confirmed that a combination of a new technique of bronze electrolytic coloring and pigment coloring, which is a conventional technique, as in Sample 3, is also possible. Further, it was also confirmed that instead of the AC electrolytic coloring which is the last step of Sample 3, pigment coloring was performed once again with a different color to enable two-tone pigment coloring.

Example 3 A colored pattern was formed on the anodic oxide film of the aluminum material in accordance with the process sequence shown in FIG. The conditions of each step were as follows: in electrophoretic coloring, in addition to blue phthalocyanine blue, red used anthraquinone-based pigments and yellow used quinacridone-based pigments.
The operation is the same as in the case of the second embodiment, except that sec. The reason why the pressure increasing speed is reduced is to reduce color unevenness when coloring the red pigment. After the decolorization step, 1 A / d
Re-anodizing was performed at m ² for 10 minutes. As a result, although the color was slightly lighter as compared to the original as a whole, the color was multicolored.

[0044]

As described above, according to the method of the present invention,
The combination of the formation of a masking pattern by printing technology and the electrophoretic coloring of the non-masked portion or the decolorization of the colored oxide film of the non-masked portion if electrophoretic coloring has been performed in advance, provides a colored pattern on the anodic oxide film of the aluminum material. Because of this, an oxide film of a colored pattern of fine patterns such as characters and figures can be formed on the surface of the aluminum material, and the pigment particles do not fall off,
As long as the anodic oxide film does not peel off, the colored pattern does not disappear, and a colorful colored pattern excellent in durability and light resistance can be obtained. In addition, it is possible to apply a colorful multicolor pattern with excellent light resistance to the anodic oxide film of aluminum material, and it is also possible to form fine patterns. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a manufacturing process of a patterned colored body of an aluminum material according to the present invention, showing a change in a sectional structure of an anodized film.

FIG. 2 is a flowchart of one embodiment of a process for producing a patterned colored body of an aluminum material according to the present invention.

FIG. 3 is a schematic view showing another embodiment of the production process of the patterned colored body of the aluminum material of the present invention, showing a change in the sectional structure of the anodic oxide film.

FIG. 4 is a flowchart of another embodiment of a process for producing a patterned colored body of an aluminum material according to the present invention.

FIG. 5 is a schematic view showing a change in the cross-sectional structure of the anodic oxide film in still another embodiment of the process for producing a patterned colored body of an aluminum material according to the present invention.

FIG. 6 is a flowchart of yet another embodiment of the process for producing a patterned colored body of an aluminum material according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum material 2 Anodized film 3 Pore 4 Masking pattern 10,11,12 Pigment

Claims (9)

[Claims] (1) a step of printing a masking pattern on the surface of an anodized film of an anodized aluminum material; (b) dipping the aluminum material having a masking pattern in a pigment dispersion to form a non-masked portion; Electrophoretic migration of pigment particles into pores of anodized film
A method for producing a patterned colored body of an aluminum material, comprising: a step of depositing and coloring; and (c) a step of removing the masking pattern. 2. (a) a step of printing a masking pattern on the surface of the anodized film of the anodized aluminum material; and (b-1) dipping the aluminum material having the masking pattern in the pigment dispersion, and performing non-masking. A step of electrophoretically dispersing and depositing pigment particles in the pores of the anodic oxide film by electrophoresis, (c) a step of removing the masking pattern, and (b-2) an aluminum material from which the masking pattern has been removed Is immersed in another pigment dispersion, and the pigment particles are electrophoresed and deposited by electrophoresis in the pores of the anodic oxide film of the masking pattern removed portion and the non-masking portion, or the aluminum material is subjected to electrolytic coloring treatment. Applying a step of coloring the anodic oxide film of the masking pattern removed portion and the non-masking portion to different colors. A method for producing a patterned colored body of an aluminum material. (A) a step of immersing an anodized aluminum material in a pigment dispersion, and electrophoretically depositing and depositing pigment particles in the pores of the anodized film by electrophoresis to color; A pattern of an aluminum material, comprising: a step of printing a masking pattern on the surface of the colored oxide film; (C) a step of decolorizing the colored oxide film in a non-masked portion; and (D) a step of removing the masking pattern. A method for producing a colored body. 4. (A-1) a step of immersing an anodized aluminum material in a pigment dispersion, and electrophoretically depositing and depositing pigment particles in pores of the anodic oxide film by electrophoresis to color. B) a step of printing a masking pattern on the surface of the colored oxide film, (C) a step of decolorizing the colored oxide film of the non-masked portion, and (A-2) a step of disposing the partially decolorized aluminum material in another pigment dispersion. The pigment particles are immersed and electrophoresed into the pores of the anodized film in the decolorized part by electrophoresis, or the decolorized aluminum material is subjected to electrolytic coloring, and the anodized film in the decolorized part is separated A method for producing a patterned colored body of an aluminum material, comprising: a step of recoloring to a color; and (D) a step of removing the masking pattern. 5. (A-1) A step of immersing an anodized aluminum material in a pigment dispersion, and electrophoretically depositing and depositing pigment particles in the pores of the anodized film by electrophoresis to color. B-1) a step of printing a masking pattern on the surface of the colored oxide film obtained in the step (A-1);
(C-1) a step of decolorizing the colored oxide film of the non-masking portion, (D-1) a step of removing the masking pattern, and (A-2) an aluminum material partially decolorized in the step (C-1). Is immersed in another pigment dispersion, and the pigment particles are electrophoresed and deposited in the pores of the anodic oxide film by electrophoresis, and the anodic oxide film in the decolored part and the masking pattern removed part is recolored to another color (B-2) a step of printing a masking pattern on the surface of the colored oxide film obtained in the above (A-2) step, (C-2) a step of decolorizing the colored oxide film of the non-masked portion, (D) -2) a step of removing the masking pattern formed in the step (B-2), and (A-3) a step of removing the aluminum material partially decolorized in the step (C-2) in another pigment dispersion. Dipped in anodized skin A pattern of an aluminum material, comprising a step of electrophoretically dispersing pigment particles in the pores of the above and re-coloring the anodic oxide film of the decolorized portion and the masking pattern removed portion to another color. A method for producing a colored body. 6. The step (A-2), the step (B-2),
The method according to claim 5, wherein the steps (C-2) and (D-2) are repeated. 7. After recoloring in the step (A-3),
(B-3) a step of printing a masking pattern on the surface of the colored oxide film obtained in the step (A-3), (C-3)
7. The method according to claim 5, further comprising: a step of decolorizing the colored oxide film on the non-masking portion; and a step of: (D-3) removing the masking pattern formed in the step (B-3). the method of. 8. The method according to claim 4, wherein the aluminum material is again subjected to anodizing before the recoloring step (A-2) or (A-3). the method of. 9. A patterned colored body of an aluminum material obtained by applying a colored pattern to an anodized film of an aluminum material according to the method of any one of claims 1 to 8.