JPH024680B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pattern coloring treatment method for aluminum or an aluminum alloy (hereinafter both will be simply referred to as aluminum), and its purpose is to treat aluminum after an anodic oxide film is formed thereon as a material to be treated. When applying pattern coloring to aluminum, by applying a unique treatment to the surface of the material to be treated before coloring and then coloring, the surface of the aluminum is coated with corners and flat areas other than the corners, or convexities and depressions on the surface. An object of the present invention is to provide a novel pattern coloring method for aluminum, which allows pattern coloring with different tones to be obtained.

Conventionally, the method of coloring the anodic oxide film of aluminum in patterns with different tones is to dip-paint aluminum that has been colored by anodizing treatment or electrolytic coloring using a thermosetting coloring paint. A method of forming a patterned colored film with different tones depending on the difference between uneven parts and flat parts (Japanese Patent Application Laid-Open No. 55-54592), or anodizing or electrolytic treatment of aluminum having edges or corners with a small radius of curvature. Colored aluminum is painted with thermosetting colored paint,
There is a known method (Japanese Unexamined Patent Publication No. 55-50491) in which the color tone is different between edges and corners and other flat parts, but these methods do not allow pattern coloring. However, since the color tone of flat areas other than uneven areas, edges, and corners is colored by paint, the resin will wear away and the underlying color tone will be exposed in areas that are colored by paint. In practice, it is unavoidable that it has drawbacks that make it difficult to use, especially outdoors.

In the method of the present invention, when applying a pattern coloring treatment to aluminum after an anodic oxidation film is formed on the material to be treated, prior to the coloring treatment, aluminum is immersed in a synthetic resin paint bath and placed in a bath with a barrier layer thickening effect. After performing a series of treatments such as anodic electrolysis treatment and peeling treatment of the paint film, coloring treatment by electrolytic coloring or dyeing including at least one electrolytic coloring is carried out, and the surface of the material to be treated is colored in corners and non-corner areas. A method of obtaining pattern coloring with different tones on flat parts or convex and concave parts of the surface, rather than coloring by painting as in the inventions of JP-A-55-54592 and JP-A-55-50491. It is possible to obtain a patterned colored film without wear or fading of parts, thereby solving the drawbacks of conventional methods at once.

Next, the method for coloring aluminum in a pattern according to the present invention will be explained specifically and in detail. In the method of the present invention, (1) an anodic oxide film is formed on the surface of aluminum by a normal method.

(2) After the anodic oxide film has been formed, the aluminum to be treated is immersed in a synthetic resin paint bath and pulled up at a predetermined speed, and the surface of the treated material is coated with corners, flat areas other than the corners, or surface convexities. A coating film with a different thickness distribution is formed between the recessed part and the recessed part.

(3) Perform anodic electrolytic treatment in a bath containing acidic or alkaline substances or their salts that have a film-enhancing effect on the barrier layer.

(4) The coating film formed on the surface of the material to be treated in the treatment step (2) above is peeled off using a peeling treatment bath such as a solvent as appropriate.

(5) Activate the anodic oxide film if necessary.

(6) Perform a coloring treatment by electrolytic coloring or dyeing that includes at least one electrolytic coloring process, and color the surface of the material to be treated in a pattern with different tones in corners and flat areas other than the corners, or in convex and concave areas of the surface. obtain.

Since the processing is performed in the order of , below, the mode of implementation and matters to be kept in mind for each of these steps will be explained in detail in the order of the steps.

(1) Anodic oxidation film treatment process There are no special restrictions on the anodization treatment in this process. Electrolytic treatment is performed to form an anodic oxide film of a desired thickness on the surface of aluminum.

(2) Paint film formation process by dipping treatment After the anodic oxide film has been formed, the aluminum is then immersed in a synthetic resin paint bath and pulled up at a predetermined speed to form a paint film with different thickness distribution on the surface of the treated material. However, since the treatment in this step has a very large influence on the realization of pattern coloring performed in the subsequent step, it is necessary to carry out the treatment appropriately while paying attention to the following points.

(b) The paint used for the immersion treatment of the material to be treated may be any paint used for normal painting, such as a solvent type using trichlene as a solvent, which is generally known as the TFS painting method, or a paint used in the electrodeposition painting method. A water-soluble type that uses water as a solvent may also be used. However, the thickness distribution of the coating film used to selectively increase the barrier layer in the next anodic electrolytic treatment process varies depending on the coating material used, so various conditions such as coating concentration and pulling speed of the material to be treated are determined. It must be set appropriately depending on the paint used. For example, Toa Paint Co., Ltd., which is a chlorinated solvent-based paint,
TFS paint, Toatri Paint S8001 (AL−
When using 2), the film thickness varies depending on the pulling speed of the material to be treated, bath temperature, solid content concentration, etc., so in order to perform anodic electrolysis treatment in the next step, it is necessary to use a flat surface with a thickness of 5 μm or less. The paint film thickness must be maintained at a bath temperature of 80°C, the solid content concentration of the paint bath must be 15% or less, and the speed at which the material to be treated can be pulled up must be
Conditions are required to achieve a low film thickness of 1 m/min or less.

On the other hand, when using electrocoating paint AL-200-50 manufactured by Shinto Paint Co., Ltd., which is a water-soluble paint,
Since the effect of coating film thickness is small, the flat part is 10μm.
It can be used sufficiently even with the following coating thicknesses, and the appropriate solids concentration considering workability is approximately 20%.
and the influence of the pulling speed is also small. In addition, although the coating thickness on the flat surface of the treated material varies depending on the properties of the paint used, the method of the present invention allows for selective thickening of the barrier layer in the subsequent anodic electrolytic treatment process. All you have to do is set as many conditions as possible.

(b) The material to be treated that has been pulled out of the synthetic resin paint dipping bath may be dried under conditions that do not completely cure the paint film, depending on the type of paint and film thickness. For example, Toa Paint Co., Ltd.
TFS paint Toatri Paint S8001 (AL−
In the case of 2) and electrocoating paint AL-200-50 manufactured by Shinto Paint Co., Ltd., which is a water-soluble paint, there is no need to dry the paint film as long as it is fixed on the surface of the material to be treated. Furthermore, since the water-soluble acrylic paint S-7450 manufactured by Shinto Paint Co., Ltd. has lower electrical insulation properties than other paints, better results can be obtained by drying it to a certain level or higher.

(c) In order to selectively apply anodic electrolytic treatment to corners and non-corner parts of the treated material or to uneven parts of the treated material in the next anodic electrolytic treatment process, the thickness of the coating film must be Since it is necessary that the corners of the surface and the flat parts other than the corners or the convex and concave parts of the surface are different, the radius of curvature of the corner or convex parts is preferably about 5 mmR or less, and the immersion treatment bath,
Depending on the processing conditions such as the thickness of the coating film, the limit radius of curvature becomes even smaller, and if the radius of curvature of the corner or convex part of the material to be treated becomes large, the corner or flat or convex part other than the corner part Since the difference in coating film thickness between the surface and the concave portion becomes smaller, it becomes difficult to perform selective anodic electrolytic treatment.

(3) Anodic electrolytic treatment process in a bath that has the effect of thickening the barrier layer When anodic electrolytic treatment is performed in this process on a material that has a coating film with a different thickness distribution, areas with low electrical resistance, In general, a thicker barrier layer is formed on areas where the coating film is thinner, and conversely, barrier layers on flat areas or recessed areas where the coating film is thicker are difficult to thicken, and require a lower voltage during electrolytic coloring later. If electrolytic coloring is performed, areas where a thick barrier layer has been formed due to anodization will not be colored, and it is possible to selectively color flat areas and concave areas other than the corners where the barrier layer has not been thickened. Become.

At that time, the anodic electrolytic treatment voltage is limited by the anodic oxide film treatment voltage, the type of coloring bath, etc., but a range of 10V to 70V is appropriate, and preferably
It is 15V to 25V. In addition, the electrolytic bath used in the anodic electrolytic treatment in this step may be an acidic or alkaline aqueous solution or a colored solution, or a colored liquid, and any bath can be used as long as it provides a thick barrier layer. Preferably,
Inorganic acids include sulfuric acid, sulfamic acid, boric acid, etc. Organic acids include oxalic acid, acetic acid, citric acid, tartaric acid, maleic acid, sulfosalicylic acid,
Examples include succinic acid, malonic acid, etc.; alkaline examples include ammonium salts of inorganic and organic acids;
There are alkaline salts, etc.

(4) Paint film stripping process In this step, a stripping bath suitable for the type of immersion bath used to form the paint film in the previous step should be used. For example, in the case of Toa Paint Co., Ltd.'s TFS paint Toatri Paint S8001 (AL-2), use Triclean, and Shinto Paint Co., Ltd.'s electrocoating paint AL-200-50.
Triethylamine, diethylamine, acetic acid, etc. are good, and water-soluble acrylic paint S manufactured by Shinto Paint Co., Ltd.
-7450, an alkaline bath is better. In this case, since sodium hydroxide and potassium hydroxide easily dissolve the anodic oxide film, it is preferable to use aqueous ammonia or an inorganic or organic ammonium salt. There is no risk of adversely affecting subsequent coloring.

(5) Activation treatment process for anodic oxide film The activation treatment in this process is not essential unlike the above steps, but is a treatment to facilitate the coloring treatment in the next process, so the dark color is It may be carried out as necessary when desired to obtain the desired color tone or depending on the type of stripping bath. The method and electrolyte used for the activation treatment in this process are not specified, and any method may be used as long as it activates the anodic oxide film, but from the viewpoint of economic efficiency, workability, etc. From there, it may be immersed in the electrolytic bath used for the initial anodic oxide film treatment, or the anodic electrolytic treatment may be performed in this bath.

(6) Coloring treatment process The material to be treated that has gone through each of the above treatment steps is then subjected to coloring treatment by electrolytic coloring or dyeing, including at least one electrolytic coloring process, to color the surface of the material to be treated at corners and corners. To obtain pattern coloring with different tones on the flat parts or on the convex and concave parts of the surface, in this case, the first coloring in this process is called the primary coloring, and the second coloring is called the secondary coloring. Then, the surface of the material to be treated from which the coating film was removed in the previous process is divided into areas that have not been subjected to anodic electrolytic treatment and areas that have been subjected to anodic electrolytic treatment, so in the case of electrolytic coloring, the first For coloring, it is necessary to color the parts that have not been subjected to anodic electrolytic treatment, and to perform the coloring treatment at a voltage that does not color the parts that have been subjected to anodic electrolytic treatment. The coloring voltage in this case varies depending on the anodic electrolytic treatment voltage or the type of coloring bath, so it cannot be stated unconditionally.
Generally, 10V to 20V is appropriate within the range of 10V to 70V. If the coloring process is completed with only the primary coloring in this way, only the parts of the surface of the material to be treated that have not been subjected to anodic electrolytic treatment will be colored.
A patterned colored film is obtained in which the areas subjected to anodic electrolytic treatment are uncolored. Then, to color the uncolored areas that have been subjected to anodic electrolytic treatment, it is sufficient to perform electrolytic coloring using a coloring bath that provides a color tone different from that obtained in the primary coloring. The voltage varies somewhat depending on the anodic electrolytic treatment voltage or the type of coloring bath, so it cannot be generalized, but it is generally within the range of 10V to 70V.
30V is appropriate.

In addition, when dyeing is used for coloring, the presence or absence of anodic electrolytic treatment does not affect the coloring.
When coloring by dyeing is applied to the primary coloring, the entire surface of the material to be treated is colored regardless of whether or not the anodic electrolytic treatment has been performed, so the secondary coloring is applied to the areas that have not been subjected to the anodic electrolytic treatment. 1st to
Electrolytic coloring is performed using a coloring bath that provides a different color tone from that of the subsequent coloring. On the other hand, when applying coloring treatment by dyeing to the secondary coloring,
A dyeing bath that applies electrolytic coloring as the primary coloring, colors only the parts of the surface of the treated material that have not been subjected to anodic electrolytic treatment, and obtains a color tone different from the primary coloring as the secondary coloring. Color the area that has been subjected to anodic electrolytic treatment. In the above case, the part of the surface of the material to be treated that has not been subjected to anodic electrolytic treatment will have two types of colors, the primary coloring and the secondary coloring, overlapping each other, so it is impossible to obtain a completely new color tone. can. In any case, the method of the present invention uses an electrolytic coloring method or a dyeing method, but it always requires electrolytic coloring one or more times.

Some specific examples of the pattern coloring method according to the present invention are listed below, but the present invention is not necessarily limited to these examples.

Example 1 A rectangle with one side of 75 mm and a corner radius of curvature.
After cutting a 6063S-T5 aluminum extrusion shape with a cross-sectional shape of 1.0 mmR into a length of 200 mm, it was subjected to the usual pretreatment and then heated to a current density of 1.2 A/dm ² in a 150 g/sulfuric acid bath at a bath temperature of 20°C. Then, the shape was immersed in a 15% aqueous solution of electrocoating paint AL-200-50 made by Shinto Paint Co., Ltd. with a resin content of 15%.
Pull it out of the liquid at a pulling speed of 0.6m/min.
It was left indoors for 30 minutes. At that time, the coating film thickness other than the corner portions was approximately 7 μm.

This shape was then subjected to anodic electrolysis treatment at a voltage of 30V for 2 minutes in a 150g/sulfuric acid bath at a bath temperature of 20℃, and then immersed in a 99% acetic acid bath at a bath temperature of 25℃ for 5 minutes. The paint film was peeled off. After that, DC cathode electrolysis was performed for 1 minute at a voltage of 11 V using nickel as an anode in a coloring bath containing 50 g of nickel sulfate and 40 g of boric acid at a bath temperature of 35°C. A bronze-colored patterned coating was obtained on the part.

Example 2 An extruded aluminum profile (6063S-T5) having the same shape and dimensions as Example 1 was subjected to the same pretreatment and anodizing treatment as in Example 1, and then treated with Shinto paint.
The shape was immersed in an aqueous solution of water-soluble acrylic paint S-7450 manufactured by Co., Ltd. with a resin content of 11%, pulled up from the solution at a pulling speed of 1.2 m/min, and dried at a temperature of 80°C for 20 minutes. Ta. At that time, the coating film thickness other than the corner portions was approximately 3 μm.

This shape was then subjected to anodic electrolysis treatment at a voltage of 18 V for 2 minutes in a 50 g/boric acid bath at a bath temperature of 25°C, and then immersed in 0.1% ammonia water at a bath temperature of 20°C for 5 minutes to form a coating film. was peeled off.

After that, the above-mentioned shape was heated in a bath temperature of 25°C and treated with nickel sulfate.
When AC electrolysis was carried out for 5 minutes at a voltage of 11 V using nickel as the counter electrode in a coloring bath containing 100 g of boric acid and 40 g of boric acid, the corners were uncolored and the other parts had a blackish-brown colored film. .

Next, this shape was heated in a bath temperature of 20°C with manganese sulfate.
When DC cathode electrolysis was performed at a voltage of 20V for 30 seconds using carbon as an anode in a coloring bath containing 10g/hydrogen peroxide/20ml/hydrogen peroxide, the corners were gold-colored and the areas other than the corners had a blackish-brown patterned colored film. Obtained.

Example 3 A rectangle with one side of 50 mm and a corner radius of curvature.
An extruded aluminum profile of 6063S-T5 with a cross-sectional shape of 0.4 mmR was cut to a length of 200 mm, subjected to the usual pretreatment, and then heated to a current density of 1.2 A/in a 150 g/sulfuric acid bath at a bath temperature of 20°C. Anodizing was carried out at dm ² for 30 minutes.

Next, this shape was immersed in an aqueous solution of water-soluble acrylic paint S-7450 manufactured by Shinto Paint Co., Ltd. with a resin content of 11%.
The shape was pulled out of the liquid at a pulling speed of 0.6 m/min and dried for 10 minutes at a temperature of 60°C. In this case, the film thickness other than the corner portions was approximately 2.5 μm.

Then, this profile was subjected to anodic electrolysis treatment at a voltage of 20 V for 2 minutes in a succinic acid bath of 50 g/succinic acid at a bath temperature of 30°C, and then immersed in 0.1% ammonia water for 2 minutes at a bath temperature of 20°C. The paint film was peeled off. Afterwards, this shape was placed in a sulfuric acid bath at a bath temperature of 20°C and 150 g/voltage.
Film activation treatment was performed by anodic electrolysis at 15V for 1 minute.

Next, the above-mentioned shape was heated in a bath temperature of 35°C and treated with nickel sulfate.
When DC cathode electrolysis was carried out for 90 seconds at a voltage of 11 V using a nickel plate as an anode in a coloring bath containing 100 g of boric acid and 45 g of boric acid, a colored film with black corners was obtained.

Afterwards, this shape was immersed for 10 minutes in a dyeing bath containing 5 g of ferric ammonium oxalate at a bath temperature of 50°C, resulting in a pattern of yellow in the areas other than the corners and black in the corners. A film was obtained.

Example 4 An extruded aluminum material (6063S-T5) having the same shape and dimensions as Example 3 was subjected to the same pretreatment and anodizing treatment as in Example 1, and then treated with Shinto Paint.
Immerse the solvent-based paint Porin AL Clear UN manufactured by Co., Ltd. in a paint bath diluted with a resin content of 5%, and pull the shape out of the bath at a pulling speed of 0.6 m/min at a temperature of 60°C.
A drying process was performed for 5 minutes. At that time, the coating film thickness was approximately 1 μm.

Next, this profile was subjected to anodic electrolysis treatment at a voltage of 20 V for 2 minutes in a 50 g/oxalic acid bath at a bath temperature of 25°C, and after being immersed in Lutzker thinner for 10 minutes to remove the coating film, the bath temperature was Film activation treatment was performed by anodic electrolysis at 20° C. and 50 g/sulfamic acid bath at a voltage of 15 V for 1 minute.

After that, the above-mentioned shape was heated in a bath temperature of 35°C and treated with nickel sulfate.
When DC cathode electrolysis was carried out for 1 minute at a voltage of 11 V using nickel as an anode in a coloring bath containing 50 g of boric acid and 40 g of boric acid, a colored film was obtained in which the corners were uncolored and the parts other than the corners were bronze-colored. It was done.

Next, this shape was heated in a bath temperature of 20°C with manganese sulfate.
When DC cathode electrolysis was performed at a voltage of 25 V for 30 seconds using carbon as an anode in a coloring bath containing 10 g/hydrogen peroxide/20 ml/hydrogen peroxide, a patterned colored film with gold color at the corners and bronze color at the other parts was obtained. was gotten.

Example 5 A rectangle with one side of 40 mm and a corner radius of curvature.
An extruded aluminum profile (6063S-T5) with a cross-sectional shape of 0.4 mmR was cut to a length of 200 mm, and after normal pretreatment, the current density was 1.2 A/dm ² at a bath temperature of 20°C and 150 g/sulfuric acid. Anodic oxidation treatment was performed for 30 minutes.

Next, this shape was coated with Toa Paint Co., Ltd.'s TFS paint Toatri Paint S8001 (AL-2) at a bath temperature of 80°C.
When the shape was immersed in a paint bath with a solid content concentration of 12% and pulled up from the bath at a pulling speed of 0.5 m/min, the coating thickness was approximately 1 μm.

The shape was then subjected to anodic electrolysis treatment at a voltage of 16 V for 2 minutes in a 25 g/ammonium oxalate bath at a bath temperature of 25°C, and then immersed in trichlene at a bath temperature of 50°C for 5 minutes to form a coating film. Peeled off.

Next, this shape was heated to a bath temperature of 20°C and stannous sulfate was heated.
When alternating current electrolysis was carried out for 5 minutes at a voltage of 11 V in a coloring bath containing 5 g of sulfuric acid and 7 g of sulfuric acid, a colored film was obtained in which the corner parts were uncolored and the parts other than the corner parts had a bronze color.

After that, this shape was heated in a bath temperature of 20℃ and selenium dioxide was heated.
When DC cathode electrolysis was carried out for 1 minute at a voltage of 17 V using carbon as an anode in a coloring bath containing 15 g of copper sulfate, 0.6 g of copper sulfate, and 0.3 g of zinc sulfate, the corners were gold-colored and the areas other than the corners were gold-colored. A bronze colored patterned coating was obtained.

As described above, according to the method of the present invention, when applying pattern coloring to aluminum after forming an anodic oxide film, prior to coloring treatment, aluminum is immersed in a synthetic resin paint bath, which has the effect of thickening the barrier layer. After a series of treatments such as anodic electrolysis treatment in a bath and peeling treatment of the paint film, coloring treatment is performed by electrolytic coloring or dyeing, which includes at least one electrolytic coloring process. It is possible to obtain a colored pattern on the surface of the material to be treated in which the color tone differs between corners and flat areas other than the corners, or between convex and concave areas of the surface, without using colored paint, and this can be used indoors. If applied to the surface treatment of various aluminum materials, including aluminum extrusion shapes for fittings,
This makes it possible to easily create pattern coloring using existing equipment, and it also has excellent corrosion resistance and provides beautiful pattern coloring, making a major contribution to the development of this industry. .

Claims (1)

[Claims] 1. An aluminum or aluminum alloy with an anodized film formed thereon is immersed as a material to be treated in a synthetic resin paint bath and pulled up at a predetermined speed, and the surface of the material to be treated is coated with corners and non-corners. A coating film with different thickness distribution is formed on flat areas or on convex and concave areas of the surface, and then anodic electrolysis treatment is performed to selectively increase the barrier layer. The coating film is peeled off, the anodic oxide film is activated if necessary, and then at least 1
It is characterized by applying a coloring treatment by electrolytic coloring or dyeing, including electrolytic coloring, to obtain pattern coloring that differs in tone between corners and flat areas other than the corners, or between convex and concave areas of the surface. A pattern coloring method for aluminum or aluminum alloy. 2. The pattern coloring treatment method according to claim 1, wherein the coloring treatment is performed by only one electrolytic coloring treatment. 3. The pattern coloring treatment method according to claim 1, wherein the coloring treatment is performed by a primary coloring treatment by electrolytic coloring and a secondary coloring treatment by electrolytic coloring that obtains a color tone different from the primary coloring. . 4. The pattern coloring treatment method according to claim 1, wherein the coloring treatment is performed by a first coloring treatment by dyeing and a second coloring treatment by electrolytic coloring which can obtain a color tone different from the first coloring. 5. The pattern coloring treatment method according to claim 1, wherein the coloring treatment is performed by a first coloring treatment by electrolytic coloring and a second coloring treatment by dyeing which obtains a color tone different from the first coloring.