JP3881392B2 - Metal surface treatment composition and metal surface treatment method - Google Patents

Description

特に好ましくは、陽イオン性イオウ原子含有樹脂中のイオウ原子の少なくとも１つは、上記化１に示すいずれかの構造である。
【００１５】
上記化１に示すいずれかの構造を有する陽イオン性イオウ原子含有樹脂によれば、樹脂の金属への配位量が増加し、より以上の耐食性、摩擦抵抗性が向上する。
【００１６】
また、陽イオン性イオウ原子含有樹脂の塩としては、ナトリウム、カリウム等のアルカリ金属塩や、カルシウム、マグネシウム等のアルカリ土類金属塩や、アンモニウム塩等が挙げられる。
【００１７】
また、本発明における陽イオン性イオウ原子含有樹脂又はその塩の分子量は、１０００〜１００００が好ましい。分子量が１０００未満の場合には、耐食性、摩擦抵抗性（以下「すべり性」という）が劣る。一方、分子量が１００００を越えると、水溶性が劣る。
【００１８】
また、本発明において、金属表面処理組成物に対して陽イオン性イオウ原子含有樹脂又はその塩の含有量は、０．０１〜１０ｇ／ｌが好ましく、より好ましくは０．１〜５ｇ／ｌである。陽イオン性イオウ原子含有樹脂又はその塩の含有量が０．０１ｇ／ｌ未満の場合には、陽イオン性イオウ原子含有樹脂又はその塩のバインダー効果が発揮されず、塗装下地用皮膜の物理的な耐久性が劣る。一方、陽イオン性イオウ原子含有樹脂又はその塩の含有量が１０ｇ／ｌを超えると、耐食性が劣化する。
【００１９】
本発明における陽イオン性イオウ原子含有樹脂は、より好ましくは分子量５００当り、フェニル基を１〜５個と、水酸基を１〜１２個と、イオウ原子を０．１〜７個と、を含有することである。分子量５００当りフェニル基が１個未満の場合には、耐食性及びすべり性が劣化する。一方、分子量５００当りフェニル基が５個を超える場合には、水溶性及び塗膜密着性が劣化する。また、分子量５００当り水酸基が１個未満の場合には、塗膜密着性及び金属表面処理液中への水溶性が劣化する。一方、分子量５００当り水酸基が１２個を超える場合には、耐食性及びすべり性が劣る。更に、分子量５００当り陽イオン性イオウ原子が０．１個未満の場合には、塗膜密着性及び金属表面処理液中への水溶性が劣化する。一方、分子量５００当り陽イオン性イオウ原子が７個を超えると、耐食性が劣る。
【００２０】
上記条件を満たす陽イオン性イオウ原子含有樹脂の例を下記に示す。
【００２１】
【化３】

Ｒ₁
／
−Ｓ⁺
＼
Ｒ₂ は、上記化１のいずれかの構造である
Ｒ₃：炭素数１０〜１８の直鎖又は分岐状のアルキル基）
【化４】

（ Ｒ₁
／
−Ｓ⁺
＼
Ｒ₂ は、上記化１のいずれかの構造である）
【化５】

Ｒ₁
／
−Ｓ⁺
＼
Ｒ₂ は、上記化１のいずれかの構造である
Ｒ₃：炭素数１０〜１８の直鎖又は分岐状のアルキル基）
【化６】

Ｒ₁
／
−Ｓ⁺
＼
Ｒ₂ は、上記化１のいずれかの構造である）
【化７】

上記化３〜化７の化合物中の水酸基によって、皮膜の塗膜密着性が向上する。また、上記化３の化合物中のフェニル基の部位によって、皮膜の耐沸水黒変性、すべり性が向上する。更に上記化３の化合物中のイオウ原子によって、皮膜の金属に対する付着性が向上する。更に、上記化３の化合物中のイオウ原子がイオン化するので、処理浴が安定になる。ここで、耐沸水黒変性とは、食缶（アルミ）において、殺菌のために行う水道水等による沸水処理時に、未塗装部の素地が水中の金属と作用して黒色化する現象をいう。
【００２２】
本発明に係る金属表面処理組成物が含有する重金属は、ジルコニウム（Ｚｒ）、チタン（Ｔｉ）、モリブデン（Ｍｏ）、タングステン（Ｗ）、ニオブ（Ｎｂ）、ニッケル（Ｎｉ）、コバルト（Ｃｏ）、マンガン（Ｍｎ）、タンタル（Ｔａ）の少なくとも１種である。好ましくは、重金属は、ジルコニウム（Ｚｒ）、チタン（Ｔｉ）、ニオブ（Ｎｂ）、マンガン（Ｍｎ）、タンタル（Ｔａ）である。上記重金属の供給源は、上記重金属の錯フッ化物が好ましく、その他硝酸塩、リン酸塩等が挙げられる。
【００２３】
本発明に係る金属表面処理組成物に対する重金属の錯フッ化物の含有量は、０．０１〜１０ｇ／ｌが好ましい。重金属の錯フッ化物の含有量が０．０１ｇ／ｌ未満の場合には、耐食性が劣化する。一方、重金属の錯フッ化物の含有量が１０ｇ／ｌを超える場合にも、耐食性が劣化する。
【００２４】
本発明に係る金属表面処理組成物は、耐食性向上のために更にリン酸又はリン酸塩を含有してもよい。リン酸又はリン酸塩としては、Ｈ₃ ＰＯ₄ 、Ｎａ₃ ＰＯ₄ 、Ｎａ₂ ＨＰＯ₄ 、ＮａＨ₂ ＰＯ₄ 、（ＮＨ₄ ）₃ ＰＯ₄ 等が挙げられる。上記金属表面処理組成物に対してリン酸又はリン酸塩の含有量は、２０ｇ／ｌ未満が好ましい。より好ましくは、０．０５〜０．１ｇ／ｌである。リン酸又はリン酸塩の含有量が２０ｇ／ｌ以上では、塗膜密着性が劣化する。
【００２５】
本発明に係る金属表面処理組成物は、必要に応じて、以下のエッチング剤やエッチング助剤を含有してもよい。
【００２６】
エッチング剤としては、フッ化水素及びその塩が挙げられる。そして、このエッチング剤は、適宜金属表面処理組成物に対して０．００５〜０．５ｇ／ｌ含有してもよい。エッチング剤の含有量が０．００５ｇ／ｌ未満の場合には、エッチング性が不足し、塗装下地用皮膜が十分に金属表面に形成されない。一方、エッチング剤の含有量が０．５ｇ／ｌを超えると、エッチングが過多になるという問題がある。
【００２７】
エッチング助剤としては、過酸化水素（Ｈ₂ Ｏ₂ ）及び／又は亜硝酸（ＨＮＯ₂ ）、及びその塩、ＨＢＦ₄ が挙げられる。そして、このエッチング助剤の過酸化水素（Ｈ₂ Ｏ₂ ）及び／又は亜硝酸（ＨＮＯ₂ ）、及びその塩は、適宜金属表面処理組成物に対して０．００５〜５ｇ／ｌ含有してもよい。上記エッチング助剤の含有量が０．００５ｇ／ｌ未満の場合には、耐食性が劣化する。一方、上記エッチング助剤の含有量が５ｇ／ｌを超えても、耐食性が劣化する。また、ＨＢＦ₄ は、適宜金属表面処理組成物に対して０．００３〜０．２ｇ／ｌ含有してもよい。ＨＢＦ₄ の含有量が０．００３ｇ／ｌ未満の場合には、耐食性が劣化する。一方、ＨＢＦ₄ の含有量が０．２ｇ／ｌを超えても、耐食性が劣化する。
【００２８】
上記組成のｐＨは、約２．０〜約５．０の範囲であり、好ましくは２．５〜３．０の範囲である。本発明の組成物と金属素材とを接触させる温度は、常温から約９０℃の範囲の温度、好ましくは約３５〜６５℃の範囲の温度である。一般には、金属素材と本発明の組成物との接触時間は、高温程短くなる。
【００２９】
金属素材は、スプレー塗布の場合約５秒〜約５分間、好ましくは１０秒〜約６０秒間本発明の組成物と接触させるのが一般的である。浸漬法の場合には、これより長い接触時間を要するのが一般的である。本発明の組成と金属素材とを接触させるには、処理液組成物と金属素材とを接触させる既知の方法を用いて行うことができる。その例を挙げれば、スプレー法、浸漬法、フローコート法、ローラーコート法である。本発明においては金属素材と本発明の組成物とを完全に接触させることが重要である。スプレー法は、本発明の組成物と金属素材とを接触させる好ましい方法である。
【００３０】
金属素材と本発明の組成物とを接触させた後、皮膜化成処理された金属素材の水洗を行えば、化成皮膜とならなかった本発明の処理液組成物を除去できるため均一な皮膜を得ることが可能である。本発明によれば、無機−有機化成皮膜を一段処理で得られることができる。一段処理法は、多段処理法に比べて多くの利点を有する。
【００３１】
このようにして、皮膜化成処理された金属素材は、次いで、乾燥される。皮膜処理された金属素材は、１８０℃から２４０℃の範囲の温度で乾燥することができる。約１８０℃未満の温度では、皮膜処理されたアルミニウム素材の耐食性及び塗膜密着性が低下する。
【００３２】
更に、本発明の好ましい他の実施態様を以下に示す。
【００３３】
１．重金属は、ジルコニウム、チタン、ニオブ、マンガン、タンタルの少なくとも１種であることを特徴とする金属表面処理組成物である。
【００３４】
２．樹脂中の陽イオン性イオウ原子の少なくとも１つが、上記の化１に示す構造を有することを特徴とする金属表面処理組成物である。
【００３５】
３．樹脂中の陽イオン性イオウ原子の少なくとも１つは、上記化２に示すいずれかの構造であることを特徴とする金属表面処理組成物である。
【００３６】
４．樹脂の塩は、アルカリ金属塩、アルカリ土類金属塩、アンモニウム塩の少なくとも１つであることを特徴とする金属表面処理組成物である。
【００３７】
５．樹脂又はその塩の分子量は、１０００〜１００００であることを特徴とする金属表面処理組成物である。
【００３８】
６．金属表面処理組成物に対する樹脂又はその塩の含有量は、０．０１〜１０ｇ／ｌであることを特徴とする金属表面処理組成物である。
【００３９】
７．金属表面処理組成物に対する樹脂又はその塩の含有量は、０．１〜５ｇ／ｌであることを特徴とする金属表面処理組成物である。
【００４０】
８．樹脂は、上記化３に示す化合物であることを特徴とする金属表面処理組成物である。
【００４１】
９．金属表面処理組成物に含有される重金属の供給源は、その重金属の錯フッ化物、硝酸塩、リン酸塩であることを特徴とする金属表面処理組成物である。
【００４２】
１０．金属表面処理組成物に対して重金属の錯フッ化物の含有量は、０．０１〜１０ｇ／ｌであることを特徴とする金属表面処理組成物である。
【００４３】
１１．更に、リン酸又はリン酸塩を含有することを特徴とする金属表面処理組成物である。
【００４４】
１２．上記「１１．」のリン酸又はリン酸塩は、Ｈ₃ ＰＯ₄ 、Ｎａ₃ ＰＯ₄ 、Ｎａ₂ ＨＰＯ₄ 、ＮａＨ₂ ＰＯ₄ 、（ＮＨ₄ ）₃ ＰＯ₄ であることを特徴とする金属表面処理組成物である。
【００４５】
１３．金属表面処理組成物に対してリン酸又はリン酸塩の含有量は、０〜２０ｇ／ｌであることを特徴とする金属表面処理組成物である。
【００４６】
１４．更にフッ化水素及びその塩を含有していることを特徴とする金属表面処理組成物である。
【００４７】
【実施例】
次に、実施例及び比較例を挙げて、本発明を具体的に説明する。
【００４８】
実施例１，３〜１１及び比較例１〜８、参考例
（１）被処理物：
Ａｌ−Ｍｎ系（ＪＩＳ−Ａ３００４）アルミニウム合金板をＤＩ加工等して得られた成型缶。
【００４９】
（２）塗装下地用皮膜評価方法：
ａ）耐沸水黒変性：
本実施例及び比較例の組成物によって表面処理を行った被処理物を沸騰水道水中に３０分間浸漬した後の外観評価を次の基準で行った。
【００５０】
○ ： 外観の変化なし
△ ： 僅かに黒変
× ： 黒変
ｂ）塗装下地用皮膜表面のすべり性：
本実施例の方法で化成処理を行った被処理物を「ＨＥＩＤＯＮ−１４型」試験機で荷重５０ｇ、触針速度３００ｍｍ／ｍｉｎ．で動摩擦係数を求めた。
【００５１】
○ ： ０．６未満
△ ： ０．６〜０．８
× ： ０．８を超える場合
ｃ）ＢＡＳＦ社製塗料（ＥＢ−７０−００１Ｎ １５０ｍｍｇ／ｍ² ／ ＥＢ−６９−００２Ｎ ６０ｍｍｇ／ｍ² ）を被処理物に塗装する。そしてこの塗装された被処理物を、ウェッジベンディング加工し、折れ曲り部をニチバン製セロテープによりテープ剥離した時の塗膜剥離評価を次の基準で行った。
【００５２】
○ ： テープ剥離幅が１５ｍｍ未満
△ ： テープ剥離幅が１５〜２０ｍｍ
× ： テープ剥離幅が２０ｍｍを超える
（３）金属表面処理条件：
（実施例１）
Ａｌ−Ｍｎ系（ＪＩＳ−Ａ３００４）成型缶を酸性脱脂剤（「サーフクリーナーＮＨＣ２５０」、日本ペイント（株）製）３０ｇ／ｌを用いて脱脂した（７５℃、６０秒スプレー）後、水洗して、リン酸ジルコニウム系処理剤（「アルサーフ ４４０」、日本ペイント（株）製）を２０ｇ／ｌに希釈した水溶液に表１に示す水溶性の樹脂Ａ−１を０．２ｇ／ｌ溶かして処理液を作成し、その処理液を用いて、５０℃で２０秒間スプレー処理を行った。処理した後、水道水で水洗し、次いで１８０℃で３０分間加熱乾燥を行った。その評価結果を表３に示す。
【００５３】
（実施例３〜１１及び比較例１〜８、参考例）
実施例３〜１１及び比較例１〜８、参考例は、水溶性の樹脂（表１に示した）と重金属の錯フッ化物とを下記の表２に示す配合量で含有する金属表面処理組成物であって、これらの金属表面処理組成物を上記実施例１に準じて、金属表面処理を行った。その評価結果を表３に示す。
【００５４】
【表１】

【化８】

【化９】

【化１０】

【化１１】

【化１２】

【化１３】

【表２】

註）*1：アルサーフ４４０；リン酸ジルコニム系処理剤、日本ペイント（株）製
【表３】

これらの結果から、本発明の金属表面処理用組成物によれば、耐沸水黒変性、すべり性、上塗塗膜密着性のいずれの性能も従来のものに比べ向上していることが判明した。
【００５５】
【発明の効果】
以上のように、本発明に係る金属表面処理組成物によれば、重金属又はその塩からなる無機皮膜によって透水性が抑制されるので、耐食性が向上する。また、樹脂又はその塩中のイオウ原子は、（重）金属に配位するので、上記無機皮膜は、そのイオウ原子を介して相互に連結させる。従って、無機皮膜の凝集破壊を防止することができ、ほぼ均一な塗装下地用皮膜を金属表面に形成することができる。このため、塗装下地用皮膜と上塗塗膜との塗膜密着性が向上する。ここで、塗装下地用皮膜とは、金属表面に形成された樹脂又はその塩によって連結された上記無機皮膜からなる皮膜をいう。更に、上記樹脂が塗装下地用皮膜表面にほぼ均一に存在するので、摩擦抵抗を下げることができ、すべり性を向上させることができる。
【００５６】
従って、本発明に係る金属表面処理組成物によれば、従来に比べ著しく耐食性や塗膜密着性を改善することができ、更に摩擦抵抗性を付与することができる。また、本発明に係る金属表面処理組成物によれば、アルミニウム又はその合金を用いて食缶を製造する場合には、ジャミング防止することができ、コイルコーティングにおいては、潤滑性を付与することができる。
【００５７】
本発明に係る金属表面処理組成物は、食缶、自動車のボディー、鋼板のコイルコーティング、建材等の金属表面処理に用いることができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a metal surface treatment composition, in particular, a metal surface composition having improved corrosion resistance, coating film adhesion and friction resistance.
[0002]
[Prior art]
Conventionally, phosphate treatment, chromate treatment, non-chromate treatment, and the like have been performed as surface treatments for metal materials such as cans, automobile bodies, and steel sheet coil coatings. For example, when an organic film such as paint or adhesive is applied to a metal surface such as iron, zinc, or aluminum, a phosphate film is formed on the metal surface by phosphating as a pretreatment. Subsequently, an organic film such as a paint is formed on the upper surface, thereby improving corrosion resistance and coating film adhesion. However, the metal surface treatment agents in conventional phosphating methods and the like have not always been sufficient for recent requirements for corrosion resistance, coating film adhesion and friction resistance (also referred to as “slip properties”).
[0003]
Therefore, in order to further improve the corrosion resistance, a method of applying a paint after applying a primer paint after a phosphate treatment has been performed. However, when the primer is applied, although the corrosion resistance and the coating film adhesion are improved, there are problems that the coating process increases and the operation becomes complicated and the coating cost increases.
[0004]
Therefore, as a metal surface treatment agent for the purpose of omitting primer coating while imparting high corrosion resistance and coating film adhesion, for example, “Metal surface treatment agent for forming a composite film” of JP-A-5-117869. Has been proposed. The metal surface treatment agent of the above publication is composed of a phosphate surface treatment liquid containing a cationic organic polymer compound or a salt thereof containing one or more cationic nitrogen atoms and having a molecular weight of 1,000 to 1,000,000. It is disclosed.
[0005]
In addition, the “surface treatment method of aluminum and its alloys” disclosed in Japanese Patent Application Laid-Open No. 51-73938 particularly provides corrosion resistance and coating film adhesion by limiting the metal to be surface-treated to aluminum or the like. Metal surface treatment methods for the purpose have been proposed. This metal surface treatment method uses a treatment liquid mainly composed of a water-soluble titanium compound and an organic polymer film-forming substance containing a water-soluble resin or emulsion resin such as vinyl acetate / vinylidene chloride and acrylic acid. Has been.
[0006]
[Problems to be solved by the invention]
However, although the metal surface treatment agent and the treatment liquid have improved corrosion resistance and coating film adhesion as compared with conventional metal surface treatment agents and the like, they have not yet reached the recent required level.
[0007]
In particular, when producing food cans using aluminum or an alloy thereof, the conventional metal surface treatment agent cannot prevent jamming, and coil coating of steel sheets has a problem of lack of lubricity. It was.
[0008]
The present invention has been made for the purpose of solving such problems, and provides a metal surface treatment composition and a treatment method for improving corrosion resistance and coating film adhesion and further imparting friction resistance. That is.
[0009]
[Means for Solving the Problems]
In order to achieve the above-described object, the metal surface treatment composition according to the present invention contains a water-soluble, water-dispersible or emulsion resin containing at least one cationic sulfur atom, and a positive electrode in the resin. The content of a water-soluble, water-dispersible or emulsion resin or salt thereof containing at least one of the ionic sulfur atoms , wherein at least one of the ionic sulfur atoms has one of the structures shown in Chemical Formula 1 above Is 0.01 to 5 g / l, and further contains a heavy metal or a salt thereof.
[0010]
According to the configuration of the invention, since the sulfur atom in the sulfur atom-containing resin or salt thereof is coordinated to the (heavy) metal, the inorganic coating is connected to each other via the sulfur atom. Therefore, cohesive failure of the inorganic coating is prevented, and a substantially uniform coating base coating film can be formed on the metal surface. For this reason, the adhesion of the coating film between the coating film for coating foundation and the top coating film is improved. The coating for coating base in the present invention refers to a coating formed on a metal surface composed of the above inorganic coating connected by a sulfur atom-containing resin formed on the metal surface or a salt thereof. Further, since the organic film-forming resin is present almost uniformly on the surface of the coating base coating film, the frictional resistance can be lowered and the sliding property can be improved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The resin or salt thereof containing at least one cationic sulfur atom contained in the metal surface treatment composition according to the present invention is, for example, either a water-soluble, water-dispersible or emulsion resin or a salt thereof. . Preferably, the cationic sulfur atom-containing resin is a compound having an epoxy resin, an acrylic resin, a urethane resin, a polybutadiene resin, a polyamide resin, or a phenol resin having one or more resin skeletons. .
[0012]
By having the resin skeleton, further corrosion resistance can be imparted to the coating on the metal surface.
[0013]
For example, at least one of a cationic sulfur atom-containing resin or a salt thereof has a structure shown in Chemical Formula 2 .
[0014]
[Chemical 2]

Particularly preferably, at least one of the sulfur atoms in the cationic sulfur atom-containing resin has one of the structures shown in Chemical Formula 1 above .
[0015]
According to the cationic sulfur atom-containing resin having any one of the structures shown in Chemical Formula 1, the amount of coordination of the resin to the metal is increased, and the further corrosion resistance and friction resistance are improved.
[0016]
Examples of the salt of the cationic sulfur atom-containing resin include alkali metal salts such as sodium and potassium, alkaline earth metal salts such as calcium and magnesium, and ammonium salts.
[0017]
In addition, the molecular weight of the cationic sulfur atom-containing resin or salt thereof in the present invention is preferably 1000 to 10,000. When the molecular weight is less than 1000, corrosion resistance and friction resistance (hereinafter referred to as “slip property”) are inferior. On the other hand, when the molecular weight exceeds 10,000, water solubility is poor.
[0018]
In the present invention, the content of the cationic sulfur atom-containing resin or the salt thereof with respect to the metal surface treatment composition is preferably 0.01 to 10 g / l, more preferably 0.1 to 5 g / l. is there. When the content of the cationic sulfur atom-containing resin or salt thereof is less than 0.01 g / l, the binder effect of the cationic sulfur atom-containing resin or salt thereof is not exhibited, and the physical properties of the coating base coating film The durability is inferior. On the other hand, when the content of the cationic sulfur atom-containing resin or its salt exceeds 10 g / l, the corrosion resistance deteriorates.
[0019]
The cationic sulfur atom-containing resin in the present invention more preferably contains 1 to 5 phenyl groups, 1 to 12 hydroxyl groups, and 0.1 to 7 sulfur atoms per molecular weight of 500. That is. When the number of phenyl groups per molecular weight is less than 1, the corrosion resistance and the slipping property are deteriorated. On the other hand, when the number of phenyl groups exceeds 500 per 500 molecular weight, water solubility and coating film adhesion deteriorate. On the other hand, when the number of hydroxyl groups per molecular weight is less than 1, the coating film adhesion and the water solubility in the metal surface treatment solution deteriorate. On the other hand, when the number of hydroxyl groups exceeds 500 per 500 molecular weight, the corrosion resistance and slipperiness are poor. Further, when the number of cationic sulfur atoms per molecular weight is less than 0.1, the adhesion of the coating film and the water solubility in the metal surface treatment solution deteriorate. On the other hand, if the number of cationic sulfur atoms exceeds 500 per 500 molecular weight, the corrosion resistance is poor.
[0020]
Examples of cationic sulfur atom-containing resins that satisfy the above conditions are shown below.
[0021]
[Chemical 3]

R ₁
/
-S ⁺
\
R ₂ is any one of the structures of Chemical Formula 1 R ₃ : a linear or branched alkyl group having 10 to 18 carbon atoms)
[Formula 4]

(R ₁
/
-S ⁺
\
R ₂ is the structure of any one of the above formula 1)
[Chemical formula 5]

R ₁
/
-S ⁺
\
R ₂ is any one of the structures of Chemical Formula 1 R ₃ : a linear or branched alkyl group having 10 to 18 carbon atoms)
[Chemical 6]

R ₁
/
-S ⁺
\
R ₂ is the structure of any one of the above formula 1)
[Chemical 7]

The coating film adhesion of the film is improved by the hydroxyl group in the compounds of Chemical Formulas 3 to 7. Further, the resistance to boiling water blackening and slipping of the film are improved by the phenyl group site in the compound of Chemical Formula 3 above. Furthermore, the adhesion of the film to the metal is improved by the sulfur atom in the compound of Chemical Formula 3 above. Furthermore, since the sulfur atom in the compound of Chemical Formula 3 is ionized, the treatment bath becomes stable. Here, boiling water blackening resistance refers to a phenomenon in a food can (aluminum) that the base of an unpainted part acts with a metal in water during the boiling water treatment with tap water or the like for sterilization.
[0022]
Heavy metals contained in the metal surface treatment composition according to the present invention are zirconium (Zr), titanium (Ti), molybdenum (Mo), tungsten (W), niobium (Nb), nickel (Ni), cobalt (Co), It is at least one of manganese (Mn) and tantalum (Ta). Preferably, the heavy metal is zirconium (Zr), titanium (Ti), niobium (Nb), manganese (Mn), or tantalum (Ta). The heavy metal supply source is preferably a complex fluoride of the heavy metal, and other examples thereof include nitrates and phosphates.
[0023]
The content of the complex fluoride of heavy metal in the metal surface treatment composition according to the present invention is preferably 0.01 to 10 g / l. When the content of the heavy metal complex fluoride is less than 0.01 g / l, the corrosion resistance deteriorates. On the other hand, even when the content of complex fluoride of heavy metal exceeds 10 g / l, the corrosion resistance deteriorates.
[0024]
The metal surface treatment composition according to the present invention may further contain phosphoric acid or a phosphate for improving corrosion resistance. Examples of phosphoric acid or phosphate include H ₃ PO ₄ , Na ₃ PO ₄ , Na ₂ HPO ₄ , NaH ₂ PO ₄ , (NH ₄ ) ₃ PO _{4 and the} like. The content of phosphoric acid or phosphate with respect to the metal surface treatment composition is preferably less than 20 g / l. More preferably, it is 0.05-0.1 g / l. When the content of phosphoric acid or phosphate is 20 g / l or more, coating film adhesion deteriorates.
[0025]
The metal surface treatment composition according to the present invention may contain the following etching agent and etching aid as necessary.
[0026]
Examples of the etching agent include hydrogen fluoride and salts thereof. And this etching agent may contain 0.005-0.5g / l suitably with respect to a metal surface treatment composition. When the content of the etching agent is less than 0.005 g / l, the etching property is insufficient, and the coating base coating film is not sufficiently formed on the metal surface. On the other hand, when the content of the etching agent exceeds 0.5 g / l, there is a problem that etching becomes excessive.
[0027]
Etching aids include hydrogen peroxide (H ₂ O ₂ ) and / or nitrous acid (HNO ₂ ), and salts thereof, and HBF ₄ . Then, hydrogen peroxide (H ₂ O ₂ ) and / or nitrous acid (HNO ₂ ) and a salt thereof as an etching aid are appropriately contained in an amount of 0.005 to 5 g / l with respect to the metal surface treatment composition. Also good. When the content of the etching aid is less than 0.005 g / l, the corrosion resistance deteriorates. On the other hand, even if the content of the etching aid exceeds 5 g / l, the corrosion resistance deteriorates. Further, HBF ₄ may contain 0.003~0.2g / l with respect to appropriate metal surface treatment composition. When the content of HBF ₄ is less than 0.003 g / l, the corrosion resistance deteriorates. On the other hand, even if the content of HBF ₄ exceeds 0.2 g / l, the corrosion resistance deteriorates.
[0028]
The pH of the composition is in the range of about 2.0 to about 5.0, preferably in the range of 2.5 to 3.0. The temperature at which the composition of the present invention is brought into contact with the metal material is a temperature in the range from room temperature to about 90 ° C, preferably in the range of about 35 to 65 ° C. In general, the contact time between the metal material and the composition of the present invention becomes shorter as the temperature increases.
[0029]
The metal material is typically contacted with the composition of the present invention for spray application for about 5 seconds to about 5 minutes, preferably 10 seconds to about 60 seconds. In the case of the immersion method, a longer contact time is generally required. The composition of the present invention and the metal material can be brought into contact with each other using a known method of bringing the treatment liquid composition into contact with the metal material. Examples thereof include spraying, dipping, flow coating, and roller coating. In the present invention, it is important to bring the metal material and the composition of the present invention into complete contact. The spray method is a preferred method of bringing the composition of the present invention into contact with a metal material.
[0030]
After the metal material and the composition of the present invention are brought into contact with each other, if the metal material subjected to the film chemical conversion treatment is washed with water, the treatment liquid composition of the present invention that has not become a chemical conversion film can be removed to obtain a uniform film. It is possible. According to the present invention, an inorganic-organic chemical conversion film can be obtained by one-step treatment. The single-stage process has many advantages over the multi-stage process.
[0031]
In this way, the metal material that has been subjected to the film chemical conversion treatment is then dried. The metal material subjected to the film treatment can be dried at a temperature in the range of 180 ° C to 240 ° C. When the temperature is less than about 180 ° C., the corrosion resistance and coating film adhesion of the aluminum material subjected to the coating treatment are lowered.
[0032]
Furthermore, other preferred embodiments of the present invention are shown below.
[0033]
1. The metal surface treatment composition is characterized in that the heavy metal is at least one of zirconium, titanium, niobium, manganese, and tantalum.
[0034]
2. It is a metal surface treatment composition characterized in that at least one of the cationic sulfur atoms in the resin has the structure shown in Chemical Formula 1 above.
[0035]
3. At least one of the cationic sulfur atoms in the resin is a metal surface treatment composition characterized by having one of the structures shown in Chemical Formula 2 above.
[0036]
4). The resin salt is a metal surface treatment composition characterized in that the resin salt is at least one of an alkali metal salt, an alkaline earth metal salt, and an ammonium salt.
[0037]
5). The metal surface treatment composition is characterized in that the resin or a salt thereof has a molecular weight of 1000 to 10,000.
[0038]
6). Content of resin or its salt with respect to a metal surface treatment composition is 0.01-10 g / l, It is a metal surface treatment composition characterized by the above-mentioned.
[0039]
7). Content of resin or its salt with respect to a metal surface treatment composition is 0.1-5 g / l, It is a metal surface treatment composition characterized by the above-mentioned.
[0040]
8). The resin is a metal surface treatment composition characterized in that it is a compound shown in Chemical Formula 3 above.
[0041]
9. The metal surface treatment composition is characterized in that the heavy metal contained in the metal surface treatment composition is a complex fluoride, nitrate or phosphate of the heavy metal.
[0042]
10. The metal surface treatment composition is characterized in that the content of the complex fluoride of heavy metal is 0.01 to 10 g / l with respect to the metal surface treatment composition.
[0043]
11. Furthermore, it is a metal surface treatment composition characterized by containing phosphoric acid or a phosphate.
[0044]
12 The metal surface characterized in that the phosphoric acid or phosphate of “11.” is H ₃ PO ₄ , Na ₃ PO ₄ , Na ₂ HPO ₄ , NaH ₂ PO ₄ , (NH ₄ ) ₃ PO _4. It is a treatment composition.
[0045]
13. Content of phosphoric acid or a phosphate with respect to a metal surface treatment composition is 0-20 g / l, It is a metal surface treatment composition characterized by the above-mentioned.
[0046]
14 The metal surface treatment composition further contains hydrogen fluoride and a salt thereof.
[0047]
【Example】
Next, an Example and a comparative example are given and this invention is demonstrated concretely.
[0048]
Examples 1, 3 to 11 and Comparative Examples 1 to 8, Reference Example (1) Object to be treated:
A molded can obtained by DI processing or the like of an Al-Mn (JIS-A3004) aluminum alloy plate.
[0049]
(2) Coating base film evaluation method:
a) Boiling water blackening resistance:
Appearance evaluation after the object to be treated having been subjected to the surface treatment with the compositions of Examples and Comparative Examples was immersed in boiling tap water for 30 minutes was performed according to the following criteria.
[0050]
○: No change in appearance △: Slightly black ×: Black change b) Sliding property of the coating base film surface:
A workpiece subjected to chemical conversion by the method of this example was loaded with a “HEIDON-14 type” testing machine with a load of 50 g and a stylus speed of 300 mm / min. The dynamic friction coefficient was obtained by
[0051]
○: Less than 0.6 △: 0.6-0.8
X: When 0.8 is exceeded c) A paint (EB-70-001N 150 mm / m ² / EB-69-002N 60 mm / m ² ) manufactured by BASF is applied to the object to be processed. Then, the coated object was subjected to wedge bending, and the film peeling evaluation when the bent portion was peeled off with a Nichiban cello tape was performed according to the following criteria.
[0052]
○: The tape peeling width is less than 15 mm. Δ: The tape peeling width is 15 to 20 mm.
X: Tape peeling width exceeds 20 mm (3) Metal surface treatment conditions:
Example 1
Al-Mn-based (JIS-A3004) molded cans were degreased using an acidic degreasing agent ("Surf Cleaner NHC250", Nippon Paint Co., Ltd.) 30 g / l (75 ° C, 60 seconds spray), then washed with water. In addition, 0.2 g / l of the water-soluble resin A-1 shown in Table 1 was dissolved in an aqueous solution obtained by diluting a zirconium phosphate-based treatment agent (“Alsurf 440”, manufactured by Nippon Paint Co., Ltd.) to 20 g / l. Was prepared and sprayed at 50 ° C. for 20 seconds using the processing solution. After the treatment, it was washed with tap water and then heat-dried at 180 ° C. for 30 minutes. The evaluation results are shown in Table 3.
[0053]
(Examples 3 to 11 and Comparative Examples 1 to 8 , Reference Example )
Examples 3 to 11 and Comparative Examples 1 to 8 and Reference Example are metal surface treatment compositions containing water-soluble resins (shown in Table 1) and heavy metal complex fluorides in the amounts shown in Table 2 below. These metal surface treatment compositions were subjected to metal surface treatment according to Example 1 described above. The evaluation results are shown in Table 3.
[0054]
[Table 1]

[Chemical 8]

[Chemical 9]

[Chemical Formula 10]

Embedded image

Embedded image

Embedded image

[Table 2]

Ii) * 1: Alsurf 440; Zirconium phosphate-based treatment agent, manufactured by Nippon Paint Co., Ltd. [Table 3]

From these results, it was found that according to the metal surface treatment composition of the present invention, all the performances of resistance to boiling water blackening, slipperiness and adhesion of the top coat film were improved as compared with the conventional ones.
[0055]
【The invention's effect】
As described above, according to the metal surface treatment composition of the present invention, the water permeability is suppressed by the inorganic film made of heavy metal or a salt thereof, so that the corrosion resistance is improved. Moreover, since the sulfur atom in resin or its salt coordinates to a (heavy) metal, the said inorganic membrane | film | coat is mutually connected through the sulfur atom. Therefore, cohesive failure of the inorganic coating can be prevented, and a substantially uniform coating base coating film can be formed on the metal surface. For this reason, the adhesion of the coating film between the coating film for coating foundation and the top coating film is improved. Here, the coating base coating refers to a coating made of the inorganic coating connected by a resin formed on a metal surface or a salt thereof. Furthermore, since the resin is present almost uniformly on the surface of the coating base coating film, the frictional resistance can be lowered and the sliding property can be improved.
[0056]
Therefore, according to the metal surface treatment composition according to the present invention, the corrosion resistance and the coating film adhesion can be remarkably improved as compared with the conventional one, and further the friction resistance can be imparted. Further, according to the metal surface treatment composition of the present invention, jamming can be prevented when producing food cans using aluminum or an alloy thereof, and lubricity can be imparted in coil coating. it can.
[0057]
The metal surface treatment composition according to the present invention can be used for metal surface treatment of food cans, automobile bodies, steel sheet coil coating, building materials and the like.

Claims (5)

A water-soluble, water-dispersible or emulsion resin containing at least one cationic sulfur atom,
At least one of the cationic sulfur atoms in the resin has one of the structures shown in Chemical Formula 1,

The content of the water-soluble, water-dispersible or emulsion resin containing at least one ionic sulfur atom or a salt thereof is 0.01 to 5 g / l,
Furthermore, the metal surface treatment composition characterized by containing a heavy metal or its salt.   2. The metal surface treatment composition according to claim 1, wherein the resin is a compound having at least one resin skeleton of an epoxy resin, an acrylic resin, a urethane resin, a polybutadiene resin, a polyamide resin, and a phenol resin. The metal surface treatment composition characterized by the above-mentioned.   2. The metal surface treatment composition according to claim 1, wherein the resin has 1 to 5 phenyl groups, 1 to 12 hydroxyl groups, and 0.1 to 7 cationic sulfur atoms per 500 molecular weight. And a metal surface treatment composition comprising:   2. The metal surface treatment composition according to claim 1, wherein the heavy metal is at least one of zirconium, titanium, molybdenum, tungsten, niobium, nickel, cobalt, manganese, and tantalum. . A water-soluble, water-dispersible or emulsion resin containing at least one cationic sulfur atom is contained, and at least one of the cationic sulfur atoms in the resin has one of the structures shown in Chemical Formula 1 above. The content of the water-soluble, water-dispersible or emulsion resin containing at least one ionic sulfur atom or a salt thereof is 0.01 to 5 g / l, and further contains a heavy metal or a salt thereof. A metal surface treatment method comprising bringing a metal surface treatment composition into contact with a metal surface, followed by washing with water and drying.