JPS59190388A - Method for coloring aluminum or aluminum alloy - Google Patents

Abstract

PURPOSE:To color easily a resin film by coating Al subjected to chemical conversion treatment with the resin film having micropores and by carrying out electrolysis in an aqueous soln. contg. a metallic salt. CONSTITUTION:Al or an Al alloy subjected to chemical conversion treatment or anodic oxidation is electrolyzed as an anode in water-soluble or water-dispersible paint to form a paint film having many electrically conductive pores. Electrolysis is then carried out in an aqueous soln. contg. a metallic salt. Electric current flows through the pores, and the metal of the metallic salt or its oxide deposits. A salt of Ni, Co, Fe, Cu, Mn, Sn or the like is used as said metallic salt. Coloring giving a fast color can be carried out.

Description

【発明の詳細な説明】 この発明は、アルミニウムまたはアルミニウム合金（以
下両者を単にアルミニウムと総称）の新規な着色方法に
関するものであって、予め化成処理又は陽極酸化処理を
施したアルミニウムに微細な空隙を有する樹脂膜を波器
した後、金属塩を含む水溶液中にて電解処理することに
よシ前記樹脂膜を着色させることを特徴とするものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for coloring aluminum or aluminum alloys (hereinafter both are collectively referred to simply as aluminum), which involves coloring aluminum that has been previously subjected to chemical conversion treatment or anodizing treatment to form fine voids. The present invention is characterized in that after corrugating the resin film having the above-mentioned properties, the resin film is colored by electrolytic treatment in an aqueous solution containing a metal salt.

従来、アルミニウムへの樹脂膜の被覆による着色方法と
しては、予め顔料を分散した着色塗料を用いて塗装した
り、染料もしくは顔料インキを使用して印刷するのが一
般的である。けれども、樹脂膜中に顔料や染料等を混在
させずに電気化学的な手段で樹脂膜を着色しようとする
場合、塗料やインキによる樹脂膜は電気抵抗が非常に大
きいため、これを本発明方法のように金属塩を含む水溶
液中で電解処理しても電流はほとんど流れず、樹脂膜を
着色することができない。Conventionally, as a method of coloring aluminum by coating it with a resin film, it is common to paint using a colored paint in which a pigment is dispersed in advance, or to print using a dye or pigment ink. However, when trying to color a resin film by electrochemical means without mixing pigments, dyes, etc. in the resin film, the resin film made of paint or ink has a very high electrical resistance. Even when electrolytically treated in an aqueous solution containing metal salts, almost no current flows and the resin film cannot be colored.

しかしながら１本発明者はこの問題について種々研究と
実験を重ねた結果、前記の樹脂膜が通常の状態ではなく
、特定の条件下にあるとき。However, as a result of various studies and experiments regarding this problem, the present inventor found that when the resin film is not in a normal state but under a specific condition.

例えばアルミニウム表面の樹脂膜が多数の空隙を有する
場合には、その空隙に電流が流れる。For example, when a resin film on an aluminum surface has many voids, current flows through the voids.

つまり電解洛中の金属イオンがこの空隙に集中して流れ
るため、当該空隙に金属又は金属化合物が析出し、樹脂
膜を着色し得ることを発見したものである。In other words, it was discovered that metal ions in the electrolysis flow concentrated into these voids, so that metals or metal compounds were deposited in the voids and could color the resin film.

次に、多数の空隙を有する樹脂膜の生成について具体的
に説明すると、このような樹脂膜をアルミニウムの表面
に生成させるには、その代表例として、電着塗装による
方法と印刷による方法を挙げることができる０ （イ）電着塗装による方法 この方法は、水溶性又は水分散性塗料中で一般的にはア
ルミニウムを陽極として電解することにより、塗料中の
顔料及び樹脂を負に帯電させてアルミニウム表面に樹脂
分を析出凝固せしめるものであって、この際の樹脂膜に
は多数の通電孔が散在しており、その通電孔の部分から
塗膜の生成が進行していくのである。よって本発明の場
合は、前記の樹脂膜生成後に金属塩を含む水溶液中で電
解処理をすれば、この通電孔を通して電流が流れ、金属
又は金属化合物が析出するのである。Next, to explain specifically how to generate a resin film with a large number of voids, typical examples of how to generate such a resin film on the surface of aluminum are electrodeposition coating and printing. (a) Electrodeposition coating method This method generally uses aluminum as an anode to electrolyze a water-soluble or water-dispersible paint to negatively charge the pigments and resin in the paint. The resin is precipitated and solidified on the aluminum surface, and the resin film at this time is scattered with a large number of energizing holes, and the formation of the coating progresses from the energizing holes. Therefore, in the case of the present invention, if electrolytic treatment is performed in an aqueous solution containing a metal salt after the resin film is formed, a current flows through the current-carrying holes, and the metal or metal compound is precipitated.

また電着塗装に際しては熱可塑性樹脂を用いるのが普通
であり、前記の塗膜生成後に焼付は乾燥を施すと、樹脂
膜の通電孔が塞がれて樹脂膜中に金属又は金属化合物が
封じ込められた状態となる。けれども、電着塗装膜を焼
付は乾燥した後で本発明の電解処理を施したのでは、樹
脂膜の通電孔が塞がれているために電流が流れず、着色
成分である金属又は金属化合物の析出が不可能となる。In addition, thermoplastic resin is usually used for electrodeposition coating, and when the above-mentioned coating film is baked and dried, the electrical holes in the resin film are closed and the metal or metal compound is trapped in the resin film. The state will be as follows. However, if the electrolytic treatment of the present invention is applied after baking and drying the electrodeposition coating film, no current will flow because the current-carrying holes in the resin film are blocked, and the metal or metal compound that is the coloring component will not flow. precipitation becomes impossible.

（リ　印刷による方法 この方法は、一般的には被塗物の表面に印刷インキをド
ツト（小さな点）状に付着させて、各ドツトの分布やイ
ンキ量によシ模様を表わすのであるが、この場合は、各
ドツト間の空隙が通電部となるため、次の工程で金属塩
を含む水溶液中にて電解処理をすると、この空隙を通し
て電流が流れ、金属又は金属化合物が析出する。(Printing method) In this method, printing ink is generally applied to the surface of the object in the form of dots (small dots), and a pattern is created depending on the distribution of each dot and the amount of ink. In this case, the gaps between the dots serve as current-carrying parts, so when electrolytic treatment is performed in an aqueous solution containing a metal salt in the next step, a current flows through these gaps and the metal or metal compound is precipitated.

次に、本発明方法を実施する際に留意すべき事項を各処
理工程について順を追って説明すると、先ず、第１工程
の化成処理及び陽極酸化処理は、アルミニウムの耐食性
を向上すると共に、その表面に被覆される樹脂膜との密
着性を良好にすることを目的とするものであって、化成
処理については、クロメート、ベーマイト並ヒニＭＢＶ
などがあり、一方、陽極酸化処理の場合は硫酸、燐酔、
蓚酸等を含む液を用いて直流、交流及び交直重畳等の波
形で電解処理すればよい。Next, the points to be kept in mind when carrying out the method of the present invention will be explained step by step for each treatment step. First, the first step, chemical conversion treatment and anodization treatment, improves the corrosion resistance of aluminum and improves its surface. The purpose is to improve the adhesion with the resin film coated on
On the other hand, in the case of anodizing treatment, sulfuric acid, phosphorescence,
Electrolytic treatment may be performed using a liquid containing oxalic acid or the like with waveforms such as direct current, alternating current, and AC/DC superposition.

また、第２番目の樹脂膜被覆工程については。Also, regarding the second resin film coating step.

前にも述べたように電着塗装による方法と印刷による方
法とがあり、被処理物の形状、着色の色調及び模様等に
応じて最も適当な処理方法を採用すればよく、条件によ
っては吹き付は塗装の方法で処理することも可能である
。As mentioned earlier, there are two methods: electrodeposition painting and printing.The most appropriate treatment method can be selected depending on the shape of the object, coloring tone, pattern, etc.; Attaching can also be done by painting.

更に、第３番目の金属塩を含む水溶液中での電解処理工
程については１通常の電解着色と同様に、その浴組成は
ニッケル、コバルト、鉄、銅、マンガン及び錫等の金属
塩を含む浴を使用すればよく、一方、電流波形について
は、直流、交流、交直重畳及びパルス電解のいずれの波
形でも実施可能である。また電解電圧についてはその波
形によっても異なるが、下地処理（化成処理又は陽極酸
化処理）や空隙の抵抗等によって左右され、下地が陽極
酸化処理の場合は、樹脂膜中ばかりでなくアルマイトの
孔中にも析出する。なお、樹脂膜が予め染料や顔料等で
着色してあれば、本工程によって得られる色調は型骨さ
れたものとなる。Furthermore, regarding the third electrolytic treatment step in an aqueous solution containing metal salts, the bath composition is similar to normal electrolytic coloring. On the other hand, as for the current waveform, any one of direct current, alternating current, AC/DC superimposed waveform, and pulsed electrolysis waveform can be used. The electrolytic voltage also varies depending on the waveform, but it also depends on the base treatment (chemical conversion treatment or anodizing treatment) and the resistance of the voids. It also precipitates. Note that if the resin film is colored in advance with a dye, pigment, etc., the color tone obtained by this step will be a textured one.

上記のように、本発明方法をアルミニウムの着色に適用
すれば、樹脂膜の空隙を巧みに利用し、当該空隙を通電
部として電解着色を施すことが出来、然かもその着色成
分は樹脂膜中に封じ込められた金属又は金属化合物なの
で、耐候性が非常に良好で容易に退色する恐れがなく、
樹脂膜自体が下地のアルミニウムと強固に密着し、優れ
た耐食性を発揮し得る事とも相俟って各種アルミニウム
製品の着色に大きく役立つものである。As mentioned above, if the method of the present invention is applied to coloring aluminum, it is possible to skillfully utilize the voids in the resin film and apply electrolytic coloring to the voids as current-carrying parts, and the coloring components are contained in the resin film. Because it is a metal or metal compound sealed in, it has very good weather resistance and does not easily fade.
Coupled with the fact that the resin film itself firmly adheres to the underlying aluminum and exhibits excellent corrosion resistance, it is greatly useful for coloring various aluminum products.

以下、この発明の代表的な実施例をいくつか次に掲げる
が、本発明は必ずしもこれらの実施例のみに拘束される
ものではない。Some typical embodiments of the present invention are listed below, but the present invention is not necessarily limited to these embodiments.

アルミニウム押出材（６０６３８−Ｔ５）を常法にょシ
脱脂、エツチング、デスマットの前処理を施し。Aluminum extrusion material (60638-T5) is pre-treated by conventional methods such as degreasing, etching, and desmutting.

１５０１／ｌの硫酸洛中で陽極電解処理し、皮膜厚さ１
０μｍの陽極酸化皮膜を得た。更にアルミニウム電着用
塗料ＡＬ−２００−５０（神東塗料製）を固型分１０％
、浴温２０’Ｃの溶液中にて電圧１２０Ｖ　、　３分間
の電着塗装を行なった。次いで、焼付乾燥を行なわずに
、硫酸マンガン１５〜．３５％過酸化水素水２０ｍ１／
ｌ、浴温２５°Ｃの溶液中で対極にカーボンを用いて電
圧９０Ｖで２分間の直流陰極電解を行なったところ、ゴ
ールド色の着色塗膜が得られた。Anodic electrolytic treatment in 1501/l sulfuric acid, resulting in a film thickness of 1
A 0 μm anodic oxide film was obtained. Furthermore, the solid content of aluminum electrodeposition paint AL-200-50 (manufactured by Shinto Paint Co., Ltd.) was 10%.
Electrodeposition was performed in a solution at a bath temperature of 20'C at a voltage of 120V for 3 minutes. Next, without baking and drying, manganese sulfate 15~. 35% hydrogen peroxide solution 20ml/
When direct current cathode electrolysis was carried out at a voltage of 90 V for 2 minutes using carbon as a counter electrode in a solution with a bath temperature of 25° C., a gold colored coating film was obtained.

その後、温度１８０’Ｃで３０分間の焼付乾燥を行なっ
て熱硬化させた。Thereafter, baking drying was performed at a temperature of 180'C for 30 minutes to thermally cure the film.

実施例２ アルミニウム押出材（６０６３Ｓ−Ｔ５）に実施例１と
同様の前処理、陽極酸化処理及び電着塗装を施し、焼付
乾燥を行なわずに、硫酸コバル）４０匂、浴温２５°Ｃ
の溶液中で対極にカーボン板を用いて電圧１４５Ｖで２
分間の直流陰極電解を行なったところ、青色の着色塗膜
が得られた。その後、温度１８０°Ｃで３０分間の焼付
乾燥を行なって熱硬化させた。Example 2 Aluminum extrusion material (6063S-T5) was subjected to the same pretreatment, anodizing treatment, and electrodeposition coating as in Example 1, without baking and drying, and was coated with cobal sulfate (cobal sulfate) 40 odor and bath temperature 25°C.
Using a carbon plate as a counter electrode in a solution of
When DC cathode electrolysis was performed for 1 minute, a blue colored coating film was obtained. Thereafter, baking drying was performed at a temperature of 180°C for 30 minutes to thermally harden the film.

実施例３ アルミニウム押出材（６０６３Ｓ−Ｔ５）に実施例１と
同様の前処理及び＠極数化処理を施し、つぎにこの試料
を風乾した後、固型分２５％からなるアクリルメラミン
樹脂（神東塗和スーパーグリミン）をインキとしてオフ
セット印刷により上記試料上に木目模様状に印刷し、次
いで、硫酸マンガン１５〜，３５％過酸化水素水２０ｒ
ｎ％の浴中で対極にカーボンを用いて、電圧９．ＯＶで
２分間の直流陰極電解を行なったところ、淡ゴールドと
濃ゴールドの木目模様塗装が得られた。その後、温度１
４０°Ｃで１０分間の焼付乾燥を行なって熱硬化させた
。Example 3 An aluminum extruded material (6063S-T5) was subjected to the same pretreatment and pole numbering treatment as in Example 1, and then the sample was air-dried. A wood grain pattern was printed on the above sample by offset printing using Tonuriwa Super Glimin) as an ink, and then 15~15 to 35% manganese sulfate and 20 liters of 35% hydrogen peroxide solution were applied.
Using carbon as a counter electrode in a bath with a voltage of 9. When direct current cathode electrolysis was carried out in OV for 2 minutes, light gold and dark gold woodgrain pattern coatings were obtained. Then temperature 1
Baking drying was performed at 40°C for 10 minutes to thermally cure the film.

Claims (1)

【特許請求の範囲】[Claims] 予め化成処理又は陽極酸化処理を施しだアルミニウムま
たはアルミニウム合金に微細な空隙を有する樹脂膜を被
損した後、金属塩を含む水溶液中にて電解処理をするこ
とにより前記樹脂膜を着色させることを特徴とするアル
ミニウムまたはアルミニウム合金の着色方法。After damaging a resin film having fine voids on aluminum or aluminum alloy that has been previously subjected to chemical conversion treatment or anodization treatment, the resin film is colored by electrolytic treatment in an aqueous solution containing a metal salt. Characteristic method of coloring aluminum or aluminum alloy.