JP3756809B2 - Electrodeposition coating method and multilayer coating film forming method - Google Patents

Description

【０１４３】
カチオン電着塗料用のアクリル樹脂の製造例
容量２リットルの４つ口フラスコにプロピレングリコールモノメチルエーテル２４６部を仕込み、窒素置換後、１１０℃に保った。
この中に、以下に示す混合物を３時間かけて滴下した。
スチレン ２５部
メチルメタクリレート １８部
ｎ−ブチルアクリレート ６部
２−ヒドロキシエチルメタクリレート １２部
プラクセルＦＭ−３（ダイセル化学工業社製 商品名） ２４部
ジメチルアミノエチルメタクリレート １５部
アゾビスイソブチルニトリル ３部
滴下終了後から１時間経過後、この中に２，２'―アゾビス（２−メチルブチロニトリル）８部をプロピレングリコールモノメチルエーテル５６部に溶かした溶液を１時間かけて滴下した。滴下終了後、これをさらに１時間１１０℃に保持したのち、メチルイソブチルケトンを加え、固形分７５％のアクリル樹脂を得た。
【０１４４】
カチオン電着塗料用の硬化剤の製造例
イソホロンジイソシアネート（ＩＰＤＩ）５０部をメチルケトオキシム４０部に４０〜６０℃で滴下した後、８０℃で１時間加熱し、固形分９０％のカチオン電着塗料用の硬化剤を得た。
【０１４５】
カチオン電着用 エマルションの製造例
上記製造例にて得た７５％アクリル樹脂を９３．３部（固形分７０部）、カチオン電着塗料用の硬化剤を３３．３部（固形分３０部）、液状有機錫２．５部（固形分１部）、１０％ギ酸８．２部を配合し、均一に攪拌した後、脱イオン水１７８．３部を強く攪拌しながら約１５分かけて滴下し、固形分３２．０％のカチオン電着用 エマルションを得た。
【０１４６】
カチオン電着塗料Ｎｏ．１の製造例
作成した３２％のカチオン電着用エマルション ３１５．６部（固形分 １０１部）、５５％の顔料ペーストＡ７０部（３８．５部）、及び純水 ３１１．９部を加え、固形分２０％のカチオン電着塗料 Ｎｏ．１を得た。
【０１４７】
カチオン電着塗料Ｎｏ．２〜Ｎｏ．４の製造例
表２のような組み合わせで、カチオン電着塗料Ｎｏ．２〜Ｎｏ．４を作成した。
【０１４８】
表２
【０１４９】
【表２】

【０１５０】
アニオン電着塗料Ｎｏ 1 の製造例
下記した着色クリア塗料で使用した着色クリア塗料用のアクリル樹脂水溶液７０部（固形分）、顔料ペースト（着色クリア塗料用のアクリル樹脂水溶液７０部（固形分）３０部とチタン白顔料２０部との分散物）５０部（固形分）、下記着色クリア塗料用のメラミン樹脂水分散液４０部（固形分）を配合し、固形分２０％に脱イオン水で調整したもの。
【０１５１】
着色クリア塗料の製造例
着色クリア塗料用のアクリル樹脂水溶液の製造例
１１５℃に保ったブチルセロソルブに、アクリル酸ｎブチル １６．７部、メタクリル酸メチル１５部、スチレン ３０部、アクリル酸２−エチルヘキシル ２０部、メタクリル酸ヒドロキシルエチル １２部、アクリル酸 ６．３部およびアゾイソブチロニトリル １部を加え、通常の条件で重合反応を行った。得られたアクリル樹脂の酸価は５０ｍｇＫＯＨ／ｇ、水酸基価は５０ｍｇＫＯＨ／ｇ、数平均分子量は４５０００であった。ついでこのアクリル樹脂のカルボキシル基をジメチルアミノエタノールで当量中和し、固形分含有率５５％のアクリル樹脂水溶液を得た。
【０１５２】
着色クリア塗料用のメラミン樹脂水分散液の製造例
温度計、撹拌機および還流冷却器を備えた２リットルの４つ口フラスコに、メラミン１２６部、８０％パラホルムアルデヒド（三井東圧化学製）２２５部、ｎ−ブタノール５９２部を入れ、１０％カセイソーダ水溶液にてｐＨ９．５〜１０．０に調整したのち、８０℃で１時間反応させた。その後、ｎ−ブタノールを８８８部加え、５％硫酸溶液にてｐＨ５．５〜６．０に調整し、８０℃で３時間反応させた。反応終了後、２０％カセイソーダ水溶液にてｐＨ７．０〜７．５まで中和し、６０〜７０℃でｎ−ブタノールの減圧濃縮を行ない、濾過して固形分２７重量％の疎水性メラミン樹脂を得た。不揮発分８０％、水／メタノール混合溶剤（重量比３５／６５）の溶剤希釈率３．６％、重量平均分子量８００。
【０１５３】
このメラミン樹脂を固形分が２５部になるように撹拌容器内にとり、アクリル樹脂水溶液（アクリル酸ｎ−ブチル、メタクリル酸メチル、スチレン、メタクリル酸２−ヒドロキシエチル、アクリル酸からなる５０％樹脂水溶液）を２０部加え、回転数１０００〜１５００回転のディスパーで撹拌しながら脱イオン水８０部を徐々に加えた後、さらに３０分間撹拌して水分散化された固形分２７％のメラミン樹脂水分散液を得た。
【０１５４】
着色クリア塗料Ｎｏ．１の製造例
前記アクリル樹脂水分散液 １６３部
前記メラミン樹脂水分散液 １３１部
アクワゾールＡＳＥ−６０（注１） ３部
チヌビン９００ （注２） １部
ジメチルアミノエタノール ０．３部
脱イオン水 １７１部
アルミニウムペースト８９１Ｋ（注３） ０．５部
上記の混合物を脱イオン水で粘度３０秒（フォードカップ＃４／２０℃）に調整して固形分４０％の水性のクリヤ塗料Ｎｏ．１を得た。
【０１５５】
パールマイカ用のペーストの製造例
パールマイカ ０．５部
りん酸基含有アクリル樹脂 １．６部
セロソルブ系溶剤 １６部
以上の成分をディスパーで混合した後、前記アクリル樹脂水分散液を６部加えてさらにディスパーで攪拌し、パールマイカ用のペーストを得た。
【０１５６】
着色クリア塗料Ｎｏ．２の製造例
前記パールマイカ用ペースト ２４．１部
前記アクリル樹脂水分散液 １６２部
前記メラミン樹脂水分散液 １３１部
アクワゾールＡＳＥ−６０（注１） ３部
チヌビン９００ （注２） １部
ジメチルアミノエタノール ０．３部
脱イオン水 １４７部
上記の混合物を脱イオン水で粘度３０秒（フォードカップ＃４／２０℃）に調整して固形分４０％の水性のクリヤ塗料Ｎｏ．２を得た。
（注１）アクワゾールＡＳＥ−６０：ロームアンドハース社製の商品名、増粘剤。
（注２）チヌビン９００：チバガイギー社製、商品名、紫外線吸収剤。
（注３）アルペースト８９１Ｋ：東洋アルミニウム社製、アルミニウム含有量７２％。
（注４）パールマイカ白：酸化鉄被覆マイカ、マーク社製、厚さ０．２〜０．５μm。
【０１５７】
実施例及び比較例
実施例１
アルミニウム板に上記チタン系処理液を乾燥膜厚が０．３μｍとなるようにバーコーターにて塗装し、最高素材到達温度１００℃で３秒間かけて焼付け乾燥させて処理膜を形成させた。
【０１５８】
次いでカチオン電着塗料Ｎｏ．１を乾燥膜厚で２０μｍの電着塗板を用いて塗装し、水洗後、１５０℃にて２０分間焼き付けを行った。
【０１５９】
その塗膜の上に、環境問題を考慮し、製造例にて得た水性の着色クリア塗料Ｎｏ．１を膜厚４０μmになるように塗装して１４０℃で２０分間焼き付け乾燥を行い、実施例１の複層塗膜を得た。
【０１６０】
実施例２〜9
表３に記載のチタン系処理液を使用して、実施例１と同様にして実施例２〜９の塗膜を形成した。
【０１６１】
実施例１０
実施例１において、カチオン電着塗料Ｎｏ．１に代えてアニオン電着塗料Ｎｏ．１を使用した以外は実施例１と同様にして実施例10の塗膜を形成した。
【０１６２】
実施例１１〜１３
表３に記載のカチオン電着塗料と着色クリア塗料を使用し、その他は実施例１と同様にして実施例１１〜１３の塗膜を形成した。
【０１６３】
実施例１４
実施例１１において、カチオン電着塗料Ｎｏ．１に代えてアニオン電着塗料Ｎｏ．１を使用した以外は実施例１１と同様にして実施例1４の塗膜を形成した。
【０１６４】
実施例１５及び１６
アルミニウム板に上記チタン系処理液を乾燥膜厚が０．３μｍとなるようにバーコーターにて塗装し、最高素材到達温度１００℃で３秒間かけて焼付け乾燥させて処理膜を形成させた。
【０１６５】
次いでカチオン電着塗料Ｎｏ．１又はアニオン電着塗料No.1を乾燥膜厚で２０μｍの電着塗板を用いて塗装し、水洗後、１５０℃にて２０分間焼き付けを行った。
【０１６６】
実施例１７
アルミニウム板に上記チタン系処理液を乾燥膜厚が０．３μｍとなるようにバーコーターにて塗装し、最高素材到達温度１００℃で３秒間かけて焼付け乾燥させて処理膜を形成させた。
【０１６７】
次いでカチオン電着塗料Ｎｏ．１を乾燥膜厚で２０μｍの電着塗板を用いて塗装し、水洗後、２０℃で３０分間放置した。
【０１６８】
その塗膜の上に製造例にて得た水性の着色クリア塗料Ｎｏ．２を膜厚４０μmになるように塗装して１４０℃で２０分間焼き付け乾燥を行い、実施例１７の複層塗膜を得た。
【０１６９】
試験結果
上記、実施例１〜1７、及び比較例１〜8で得られた塗膜の性能結果を表３、４に示す。
表３
【０１７０】
【表３】

【０１７１】
表４
【０１７２】
【表４】

【０１７３】
（注５）ルーガベーククリア：関西ペイント社製、商品名、アクリル系樹脂／アミノ樹脂系有機溶剤型クリア塗料。
【０１７４】
（注６）耐候性：ＪＩＳ Ｋ−５４００ ９．８．１に規定するサンシャインカーボンアーク灯式による促進耐候性試験を照射時間が１０００時間となるまで行った試験板表面に、カッター刃でクロスカットを入れセロファンテープにて付着テストを行った。○：問題なく良好。 △：クロスカット部の一部が剥がれる。×：塗膜が全面剥がれる。
【０１７５】
（注７）光輝感：複層塗膜の外観を目視評価した。◎：塗面にかなりメタリック調、又はパール調の３次元的な奥行き感や立体感がある。 ○：塗面にメタリック調、又はパール調の３次元的な奥行き感や立体感がある。△：塗面にメタリック調、又はパール調の３次元的な奥行き感や立体感がほとんど見られない。×：塗面にメタリック調、又はパール調の３次元的な奥行き感や立体感がない。
（注８）６０°グロス：６０°鏡面反射率（％）
（注９）密着性：塗装板を４０℃の温水に１０日間浸漬した後、塗膜面にナイフを使用して約２mmの巾で縦、横それぞれ１１本の切り目を入れ、その表面に２４mm巾のセロハン粘着テープを密着させ、強く剥離した時のゴバン目部の密着性を下記基準で評価した。○：全く剥離なし、△：若干剥離あり、×：著しい剥離あり。
（注10）耐食性：塗装板に素地まで達するクロスカットを入れ、これをＪＩＳＺ−２３７１に準じて７２０時間耐塩水噴霧試験を行った後、水洗し、一般部のサビ、フクレ等を下記基準で評価するとともに、クロスカット部にセロハン粘着テ−プを密着させ瞬時に剥がした時のクロスカット部の最大剥離幅（片側）を表記した。○：塗面にサビ、フクレ等の発生が認められない、△：塗面にわずかにサビ又はフクレの発生が認められる、×：塗面に著しいサビ又はフクレの発生が認められる。
（注11）端面被覆性：平坦部の硬化膜厚が２０μｍとなる条件で，エッジ部角度４５°を有する鋼板に電着塗装し，所定の焼付条件で硬化させて試験板を作成した。試験板のエッジ部が垂直になる様にソルトスプレー装置にセットし，ＪＩＳ−Ｚ−２３７１塩水フンム試験により１６８時間後のエッジ部の防食性を評価した。◎：サビ発生全くなし、○：サビわずかに発生、×：サビ著しく発生[0001]
BACKGROUND OF THE INVENTION
The present invention provides an electrodeposition coating method and a multilayer coating film forming method having a novel design and having excellent finish, weather resistance, corrosion resistance, and anticorrosion properties, which have been subjected to rust prevention treatment instead of phosphate treatment About.
[0002]
[Prior art and its problems]
Conventionally, a substrate treatment of an automobile body is generally performed with a phosphate treatment for the purpose of improving corrosion resistance, improving paint adhesion, and the like.
[0003]
However, the phosphate treatment usually has a problem of hexavalent chromium since the post treatment (chromium sealing treatment) with a solution containing hexavalent chromium is usually performed after the phosphate treatment. This hexavalent chromium compound is a very harmful substance because many public institutions, including IARC (International Agency for Research on Cancer Review), have designated it as a carcinogenic substance for the human body.
[0004]
Further, in the phosphate treatment, a phosphoric acid compound that has not been involved in film formation is precipitated as sludge, and it is necessary to treat this sludge as industrial waste, which has problems such as environmental measures and disposal costs.
[0005]
Conventionally, an anionic electrodeposition coating or a cationic electrodeposition coating is applied to the surface of the phosphate treatment film. As such an electrodeposition coating, an acrylic colored electrodeposition paint or a polyester colored electrodeposition paint can be used in place of the conventional epoxy electrodeposition paint, thereby forming a coating film excellent in weather resistance. It is thought that it can be used as a coating film for one coat.
[0006]
In addition, colored electrodeposition paints in which a color pigment is blended in an acrylic electrodeposition paint have been developed. However, these materials have a problem that design properties such as glitter and denseness cannot be obtained.
[0007]
In addition, there is a method of adding bright pigments such as metallic pigments and pearl pigments together with other pigments when blending cationic electrodeposition paints in order to obtain a bright feeling and a dense feeling. In the range of 10 to 25% by weight), the glittering feeling and denseness of the glittering pigment could not be sufficiently exhibited, and a novel design was not obtained.
[0008]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have applied an acrylic colored electrodeposition paint or a polyester colored electrodeposition paint on the surface of a metallic material treated with a titanium-based treatment agent, and It has been found that the above-mentioned problems can be solved by applying a colored clear paint having a glittering feeling to the surface of the electrodeposition coating film, and the present invention has been completed.
[0009]
    That is, the present invention is 1,Contains titanium obtained by reacting at least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low condensates, titanium hydroxide and titanium hydroxide low condensates with hydrogen peroxide waterTitanium treatment liquid(Hereafter, it may be abbreviated as “titanium-based treatment liquid (A).”)Processed withOf aluminum or steelAn electrodeposition coating method characterized in that an acrylic colored electrodeposition paint or a polyester colored electrodeposition paint is applied to the surface of a metallic material (hereinafter sometimes abbreviated as “present invention 1”);2, An electrodeposition coating method in which the metallic material is an automobile body or an automobile member,3,An electrodeposition coating method, wherein the electrodeposition paint is an anionic electrodeposition paint;4, An electrodeposition coating method, wherein the electrodeposition paint is a cationic electrodeposition paint;5, above1 to4A method for forming a multilayer coating film (hereinafter referred to as “the present invention”), characterized in that a colored clear paint containing a glittering pigment is applied to the surface of the electrodeposition coating film formed by the method according to any one of the above. 2 ”). )
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The present inventions 1 and 2 will be sequentially described below.
[0011]
Invention 1:
In the present invention 1, examples of the metallic material to be treated with the titanium-based treatment liquid include iron, aluminum, anodized, alloys containing these metals, and plating of these metals and alloys. Is a vehicle body or a part such as a passenger car, a truck, or a motorcycle using these. Among these metallic materials, aluminum-based metallic materials are particularly preferable because they are effective in reducing the weight of vehicles such as automobiles.
[0014]
In the present invention 1, the titanium-based treatment liquid (A) isAqueous solution containing titanium obtained by reacting at least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low condensates, titanium hydroxide and titanium hydroxide low condensates with hydrogen peroxide. It is a liquid.
[0015]
As the aqueous liquid, any conventionally known liquid can be appropriately selected and used without particular limitation as long as it is described above.
[0016]
The hydrolyzable titanium compound described above is a titanium compound having a hydrolyzable group that directly binds to titanium, and generates titanium hydroxide by reacting with water such as water or water vapor.
[0017]
In the hydrolyzable titanium compound, all of the groups bonded to titanium may be hydrolyzable groups, or one part thereof may be a hydrolyzed hydroxyl group.
[0018]
The hydrolyzable group is not particularly limited as long as it generates titanium hydroxide by reacting with moisture as described above. For example, a lower alkoxyl group or a group that forms a salt with titanium (for example, a halogen atom) (Chlorine, etc.), hydrogen atoms, sulfate ions, etc.).
[0019]
The hydrolyzable titanium compound containing a lower alkoxyl group as the hydrolyzable group is particularly a tetra of general formula Ti (OR) 4 (wherein R is the same or different and represents an alkyl group having 1 to 5 carbon atoms). Alkoxy titanium is preferred.
[0020]
Examples of the alkyl group having 1 to 5 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, and tert-butyl group. Can be mentioned.
[0021]
Typical examples of the hydrolyzable titanium compound having a group capable of forming a salt with titanium as a hydrolyzable group include titanium chloride and titanium sulfate.
[0022]
The hydrolyzable titanium compound low condensate is a low condensate of the above hydrolyzable titanium compounds.
The low condensate may be either all of the groups bonded to titanium are hydrolyzable groups or one part thereof is a hydrolyzed hydroxyl group.
[0023]
Further, orthotitanic acid (titanium hydroxide gel) obtained by a reaction between an aqueous solution such as titanium chloride or titanium sulfate and an alkaline solution such as ammonia or caustic soda can be used as a low condensate.
[0024]
The degree of condensation in the hydrolyzable titanium compound low condensate or titanium hydroxide low condensate described above can be a compound of 2 to 30, and in particular, a titanium having a condensation degree of 2 to 10 is preferably used. As the system treatment liquid (A), any conventionally known liquid can be used without particular limitation as long as it is an aqueous liquid containing titanium obtained by reacting the above-described titanium compound with hydrogen peroxide. .
Specifically, the following can be mentioned.
[0025]
(1) A titanyl ion hydrogen peroxide complex or a titanic acid (peroxotitanium hydrate) aqueous solution obtained by adding hydrogen peroxide to a hydrous titanium oxide gel or sol (Japanese Patent Laid-Open Nos. 63-35419 and 1) -224220).
[0026]
(2) A liquid for forming a titania film obtained by synthesizing a titanium hydroxide gel produced from an aqueous solution of titanium chloride or titanium sulfate and a basic solution with the action of hydrogen peroxide (Japanese Patent Laid-Open Nos. 9-71418 and 10) -67516).
[0027]
In the titania film forming liquid described above, titanium hydroxide gel called orthotitanic acid is precipitated by reacting titanium chloride or titanium sulfate aqueous solution having a salt forming group with alkali solution such as ammonia or caustic soda. Let
[0028]
Next, the titanium hydroxide gel is separated by decantation with water, washed thoroughly with water, further added with aqueous hydrogen peroxide to decompose and remove excess hydrogen peroxide, whereby a yellow transparent viscous liquid can be obtained.
[0029]
The precipitated orthotitanic acid is in a gel state polymerized by OH polymerization or hydrogen bonding, and cannot be used as an aqueous liquid containing titanium as it is.
[0030]
When hydrogen peroxide solution is added to this gel, a part of OH becomes peroxidized and dissolves as peroxotitanate ions, or it becomes a kind of sol in which the polymer chain is divided into low molecules, resulting in excess peroxidation. Hydrogen decomposes into water and oxygen, and can be used as an aqueous liquid containing titanium for forming an inorganic film.
[0031]
Since this sol contains only oxygen and hydrogen atoms in addition to titanium atoms, when it is changed to titanium oxide by drying or firing, only water and oxygen are generated, so carbon components necessary for thermal decomposition such as sol-gel method and sulfate Further, it is not necessary to remove the halogen component, and a crystalline titanium oxide film having a relatively high density can be formed even at a lower temperature than in the past.
[0032]
(3) Peroxotitanium hydrate is formed by adding hydrogen peroxide to an inorganic titanium compound aqueous solution of titanium chloride or titanium sulfate, and a solution obtained by adding a basic substance to the solution is allowed to stand or heat. After forming a precipitate of the titanium hydrate polymer, at least the dissolved components other than water derived from the titanium-containing raw material solution are removed, and further a solution for forming titanium oxide (specialized by reacting with hydrogen peroxide). JP 2000-247638 and JP 2000-247639).
[0033]
As the titanium-based treatment liquid (A), an aqueous liquid containing titanium obtained by the above-described known method can be used, and further contains titanium obtained by a method of manufacturing by adding a titanium compound to hydrogen peroxide water. An aqueous liquid can be used.
[0034]
The titanium compound contains a group represented by the general formula Ti (OR) 4 (wherein R is the same or different and represents an alkyl group having 1 to 5 carbon atoms) to be hydroxylated by hydrolysis. It is preferable to use a hydrolyzable titanium compound or its hydrolyzable titanium compound low condensate.
[0035]
The mixing ratio of the hydrolyzable titanium compound and / or its low condensate (hereinafter simply referred to as “hydrolyzable titanium compound a”) and hydrogen peroxide is 10 parts by weight of hydrolyzable titanium compound a. In terms of hydrogen peroxide, it is preferably in the range of 0.1 to 100 parts by weight, particularly 1 to 20 parts by weight.
If the amount is less than 0.1 parts by weight in terms of hydrogen peroxide, chelate formation is not sufficient and white turbid precipitation occurs.
[0036]
On the other hand, if it exceeds 100 parts by weight, unreacted hydrogen peroxide tends to remain, and dangerous active oxygen is released during storage.
[0037]
The hydrogen peroxide concentration of the hydrogen peroxide solution is not particularly limited, but is preferably in the range of 3 to 30% by weight from the viewpoint of ease of handling and the solid content of the product liquid related to coating workability.
[0038]
The titanium-based treatment liquid (A) using the hydrolyzable titanium compound a reacts the hydrolyzable titanium compound a with hydrogen peroxide within a reaction temperature of 1 to 70 ° C. for 10 minutes to 20 hours. Can be manufactured.
[0039]
The titanium-based treatment liquid (A) using the hydrolyzable titanium compound a has a hydroxyl group by hydrolyzing the hydrolyzable titanium compound with water by reacting the hydrolyzable titanium compound a with hydrogen peroxide. It is presumed that the titanium compound is formed and then coordinated to the hydroxyl group-containing titanium compound in which hydrogen peroxide is formed, and this hydrolysis reaction and coordination by hydrogen peroxide occur simultaneously. There is a chelate solution that is extremely stable at room temperature and can withstand long-term storage.
[0040]
The titanium hydroxide gel used in the conventional production method is partially three-dimensionalized by Ti—O—Ti bonds, and the composition obtained by reacting this gel with hydrogen peroxide is essentially different in terms of composition and stability.
[0041]
When the titanium-based treatment liquid (A) using the hydrolyzable titanium compound a is subjected to heat treatment or autoclave treatment at 80 ° C. or higher, a titanium oxide dispersion liquid containing crystallized ultrafine particles of titanium oxide is obtained. Below 80 ° C., the crystallization of titanium oxide does not proceed sufficiently.
[0042]
In the titanium oxide dispersion produced in this way, the particle diameter of the titanium oxide ultrafine particles is 10 nm or less, preferably in the range of 1 nm to 6 nm. The appearance of the dispersion is translucent. When the particle diameter is larger than 10 nm, the film forming property is deteriorated (breaking occurs at 1 μm or more), which is not preferable.
This dispersion can be used as well.
[0043]
The titanium-based treatment liquid (A) using the hydrolyzable titanium compound a can form a dense titanium oxide film with excellent adhesion by itself by coating and drying on a steel plate material or by heat treatment at a low temperature. . As the heat treatment temperature, for example, the titanium oxide film is preferably formed at a temperature of 200 ° C. or lower, particularly 150 ° C. or lower.
[0044]
The titanium-based treatment liquid (A) using the hydrolyzable titanium compound a forms an amorphous titanium oxide film containing some hydroxyl groups at the above temperature. In addition, a titanium oxide dispersion that has been heat-treated at 80 ° C. or higher can form a crystalline titanium oxide film simply by coating, and thus is useful as a coating material for materials that cannot be heat-treated.
[0045]
The titanium-based treatment liquid (A) is obtained by further reacting a hydrolyzable titanium compound and / or a hydrolyzable titanium compound low condensate similar to the above in the presence of a titanium oxide sol with hydrogen peroxide. A titanium-based treatment liquid containing titanium (hereinafter abbreviated as “titanium-based treatment liquid (A-1)”) can be used.
[0046]
As the hydrolyzable titanium compound and / or the hydrolyzable titanium compound low condensate (hydrolyzable titanium compound a), the general formula Ti (OR) 4 (wherein R is the same or different and has 1 to It is preferable to use a titanium monomer or a hydrolyzable titanium compound low-condensate containing a group which is hydrolyzed to become a hydroxyl group.
[0047]
The titanium oxide sol described above is a sol in which amorphous titania and anatase titania fine particles are dispersed in water (for example, an alcohol-based or alcohol-ether-based aqueous organic solvent may be contained as necessary).
[0048]
A conventionally well-known thing can be used as said titanium oxide sol.
[0049]
Examples of the titanium oxide sol include (1) those obtained by hydrolyzing a titanium-containing solution such as titanium sulfate and titanyl sulfate, (2) those obtained by hydrolyzing an organic titanium compound such as titanium alkoxide, 3) Amorphous titania sol in which titanium oxide aggregates such as those obtained by hydrolyzing or neutralizing titanium halide solutions such as titanium tetrachloride are dispersed in water, and anatase titanium fine particles by firing the titanium oxide aggregates It is possible to use a product obtained by dispersing this in water. Amorphous titania can be converted into anatase titania by firing at least at a temperature above the crystallization temperature of anatase, for example, at a temperature of 400 ° C. to 500 ° C. or higher.
[0050]
As an aqueous sol of the titanium oxide, for example, TKS-201 (manufactured by Teika Co., Ltd., trade name, anatase crystal form, average particle diameter 6 nm), TA-15 (manufactured by Nissan Chemical Co., Ltd., trade name, Anatase crystal form), STS-11 (Ishihara Sangyo Co., Ltd., trade name, anatase crystal form) and the like.
[0051]
The weight ratio of the titanium oxide sol and the titanium hydrogen peroxide reactant when used for reacting the hydrolyzable titanium compound a with hydrogen peroxide is 1/99 to 99/1, preferably about 10/90. ~ 90/10 range.
When the weight ratio is less than 1/99, the effect of adding titanium oxide sol such as stability and photoreactivity is not observed, and when it exceeds 99/1, the film forming property is inferior, which is not preferable.
[0052]
The mixing ratio of the hydrolyzable titanium compound a and the hydrogen peroxide solution is in the range of 0.1 to 100 parts by weight, particularly 1 to 20 parts by weight in terms of hydrogen peroxide, based on 10 parts by weight of the hydrolyzable titanium compound a. Is preferred. If the amount is less than 0.1 parts by weight in terms of hydrogen peroxide, chelate formation is not sufficient and white turbid precipitation occurs. On the other hand, if it exceeds 100 parts by weight, unreacted hydrogen peroxide tends to remain, and dangerous active oxygen is released during storage.
[0053]
The hydrogen peroxide concentration of the hydrogen peroxide solution is not particularly limited, but is preferably in the range of 3 to 30% by weight from the viewpoint of ease of handling and the solid content of the product liquid related to coating workability.
[0054]
The titanium-based treatment liquid (A-1) is obtained by reacting the hydrolyzable titanium compound a with hydrogen peroxide within a reaction temperature range of 1 to 70 ° C. for 10 minutes to 20 hours in the presence of a titanium oxide sol. Can be manufactured.
[0055]
In the titanium-based treatment liquid (A-1), the hydrolyzable titanium compound a is hydrolyzed with water by reacting the hydrolyzable titanium compound a with hydrogen peroxide water, thereby generating a hydroxyl group-containing titanium compound. It is presumed that hydrogen peroxide is coordinated to the hydroxyl group-containing titanium compound produced, and is obtained by this hydrolysis reaction and coordination by hydrogen peroxide occurring simultaneously, and is stable at room temperature. Produces a chelating solution that is extremely high and can withstand long-term storage.
The titanium hydroxide gel used in the conventional production method is partially three-dimensionalized by Ti—O—Ti bond, and the product obtained by reacting this gel with hydrogen peroxide is essentially different in terms of composition and stability. In addition, by using a titanium oxide sol, it is possible to prevent thickening due to partial condensation reaction during synthesis. The reason is considered to be that the condensation reaction product is adsorbed on the surface of the titanium oxide sol and prevents polymerization in the solution state.
[0056]
Further, when the titanium-based treatment liquid (A-1) is subjected to a heat treatment or an autoclave treatment at 80 ° C. or higher, a titanium oxide dispersion containing ultrafine particles of crystallized titanium oxide is obtained. Below 80 ° C., the crystallization of titanium oxide does not proceed sufficiently. In the titanium oxide dispersion produced in this way, the particle diameter of the titanium oxide ultrafine particles is 10 nm or less, preferably in the range of 1 nm to 6 nm.
The appearance of the dispersion is translucent. When the particle diameter is larger than 10 nm, the film forming property is deteriorated (breaking occurs at 1 μm or more), which is not preferable. This dispersion can be used as well.
[0057]
The titanium-based treatment liquid (A-1) can form a dense titanium oxide film excellent in adhesion by itself by applying and drying a metal material or by heat treatment at a low temperature. As the heat treatment temperature, for example, the titanium oxide film is preferably formed at a temperature of 200 ° C. or lower, particularly 150 ° C. or lower.
[0058]
The titanium-based treatment liquid (A-1) forms an anatase-type titanium oxide film containing some hydroxyl groups at the above temperature.
[0059]
As the titanium-based treatment liquid (A), the titanium-based treatment liquid and the titanium-based treatment liquid (A-1) using the hydrolyzable titanium compound a have performances excellent in storage stability and corrosion resistance. It is preferable to use one.
[0060]
In the titanium-based treatment liquid (A), other pigments and sols can be added and dispersed as necessary. Examples of the additive include commercially available titanium oxide sol, titanium oxide powder, mica, talc, silica, barita, clay, and the like.
[0061]
The titanium-based treatment liquid (A) can contain at least one compound selected from a phosphoric acid compound, a metal hydrofluoric acid, and a metal hydrofluoride.
[0062]
Examples of the phosphoric acid compound include phosphoric acid, strong phosphoric acid, triphosphoric acid, hypophosphoric acid, hypophosphoric acid, trimetaphosphoric acid, diphosphoric acid, diphosphoric acid, pyrophosphoric acid, pyrophosphoric acid , Monophosphoric acids such as metaphosphoric acid, metaphosphoric acid, phosphoric acid (orthophosphoric acid), and phosphoric acid derivatives and salts thereof, condensed polyphosphoric acids such as tripolyphosphoric acid, tetraphosphoric acid, hexaphosphoric acid, and condensed phosphoric acid derivatives, and these And the like. These compounds can be used alone or in combination of two or more.
Moreover, as an alkali compound which forms above-mentioned salt, organic or inorganic alkali compounds, such as lithium, sodium, potassium, ammonium, are mentioned, for example.
[0063]
Furthermore, it is preferable to use a phosphate compound that is soluble in water. As phosphoric acid compounds, sodium pyrophosphate, sodium tripolyphosphate, sodium tetraphosphate, metaphosphoric acid, ammonium metaphosphate, sodium hexametaphosphate, etc. are particularly excellent in storage stability of coating agents and rust prevention properties of coating films. It is preferable to use this because it exhibits the effect. The compound of the titanium-based treatment liquid (A) and the phosphoric acid compound has a complex structure formed by coordinating the acidic phosphoric acid group ions bonded to the phosphoric acid compound to titanium ions. it is conceivable that.
[0064]
In addition, such a reaction can be easily carried out by simply mixing the two components. For example, by leaving the mixture at room temperature (20 ° C.) for about 5 minutes to about 1 hour, the mixture can be forced. In the case of overheating, for example, it can be heated at about 30 to about 70 ° C. for about 1 minute to about 30 minutes.
[0065]
Examples of the metal hydrofluoric acid and the metal hydrofluorate include, for example, zirconium hydrofluoric acid, titanium hydrofluoric acid, silicohydrofluoric acid, zirconium fluoride, titanium fluoride, and silicon fluoride. A salt etc. can be mentioned. Examples of the salt that forms a metal hydrofluoric acid salt include sodium, potassium, lithium, and ammonium. Among them, potassium and sodium are preferable, and specific examples include potassium potassium fluoride, titanium potassium fluoride, Examples thereof include sodium silicofluoride and potassium silicofluoride.
[0066]
The phosphoric acid compound, metal hydrofluoric acid and metal hydrofluoric acid salt can be used singly or in combination of two or more. The blending ratio of the phosphoric acid compound is the same as that of the titanium-based treatment liquid (A). The amount in the range of 1 to 400 parts by weight, particularly 10 to 200 parts by weight is preferable with respect to 100 parts by weight of the solid content.
[0067]
Moreover, an aqueous organic polymer compound can be mix | blended with a titanium type processing agent as needed.
[0068]
Since the titanium-based treatment liquid becomes a stable liquid in a neutral or acidic region, a pH range of 1 to 7, particularly 1 to 5 is particularly preferable.
[0069]
For the titanium-based treatment liquid, if necessary, for example, in addition to the above-described components, thickeners, surfactants, antibacterial agents, rust preventives (tannic acid, phytic acid, benzotriazole, etc.), color pigments, Pigments such as extender pigments and rust preventive pigments can be contained.
[0070]
Further, the titanium-based treatment liquid can be used by diluting with a hydrophilic solvent such as methanol, ethanol, isopropyl alcohol, ethylene glycol, or propylene glycol, if necessary.
[0071]
The material to be coated with the titanium-based treatment liquid is not limited as long as it is a metal material used for an automobile body. In particular, iron, aluminum and alloys containing these metals, and these metals and alloys Examples thereof include passenger cars, trucks, motorcycles and other vehicle bodies using these, and parts thereof.
[0072]
A treatment film can be formed by coating the titanium-based treatment liquid on the metallic article and drying it. The titanium-based treatment liquid can be applied onto the substrate by a known coating method such as immersion coating, shower coating, spray coating, electrodeposition coating, or the like. The drying conditions for the titanium-based treatment liquid are usually preferably about 2 seconds to about 30 minutes under conditions where the material maximum temperature reaches about 60 to 200 ° C.
[0073]
Moreover, as a dry film thickness of a titanium processing liquid, the range of 0.001-10 micrometers normally, especially 0.1-3 micrometers is preferable. If it is less than 0.001 μm, the performance such as corrosion resistance and water resistance is inferior. On the other hand, if it exceeds 10 μm, the treated film is cracked and chipping resistance is inferior.
[0074]
Next, an electrodeposition paint is applied on the titanium-based treatment film. As the electrodeposition paint, either a cationic electrodeposition paint or an anion electrodeposition paint can be used, but a cationic electrodeposition paint is preferred from the viewpoint of corrosion resistance.
[0075]
As the cationic electrodeposition paint, a known cationic electrodeposition paint obtained by mixing and dispersing a cationic resin composition in water can be used.
[0076]
As a cationic electrodeposition coating material, acrylic resin (including acrylic-modified epoxy resin) and polyester resin are used as a base resin from the viewpoint of weather resistance, and a curing agent component that cures with these resins is internal (bonded to the base resin) or external (bonded to the base resin). A cationic electrodeposition paint having a curable resin having a curing agent mixed) is preferred, and conventionally known amine-added epoxy resins can also be used in combination as other resins in terms of corrosion resistance.
[0077]
Acrylic resin cationic electrodeposition paint:
The acrylic resin used as the base resin for the paint is obtained by radical copolymerization reaction of a hydroxyl group-containing (meth) acryl monomer, an amino group-containing (meth) acryl monomer, and, if necessary, other radical copolymerizable monomers. The radical copolymerization reaction can be performed by a conventionally known method, for example, a solution polymerization method.
[0078]
Examples of the hydroxyl group-containing (meth) acrylic monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and caprolactone. (For example, Plaxel FA-2, FM-3, etc. are trade names made by Daicel Corporation.) These can be used alone or in combination of two or more.
[0079]
Examples of amino group-containing (meth) acrylic monomers include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, Examples thereof include N-di-t-butylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylamide.
[0080]
Further, in addition to the amino group-containing monomer for water solubilization, it is also possible to use those obtained by ring-opening copolymerization of glycidyl (meth) acrylate and adding an active hydrogen-containing amine compound at the terminal.
[0081]
Examples of other monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t- Examples include butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, styrene, vinyltoluene, α-methylstyrene, and the like.
[0082]
Examples of active hydrogen-containing amine compounds include primary mono- and polyamines, secondary mono- and polyamines, or primary and secondary mixed polyamines, secondary mono- and polyamines having ketimized primary amino groups, and ketiminated Examples thereof include hydroxy compounds having a primary amino group. Specifically, diethylamine, diethanolamine, ketiminates of diethyltriamine, and the like are preferably used.
[0083]
The hydroxyl value of the acrylic resin is usually in the range of 10 to 300 mgKOH / g, preferably 20 to 200 mgKOH / g, and the number average molecular weight is in the range of 2,000 to 100,000, preferably 3,000 to 50. Within the range of 1,000.
[0084]
The acrylic-modified epoxy resin is, for example, an α, β-ethylenically unsaturated group-containing epoxy resin obtained by reacting an epoxy resin component with an α, β-ethylenically unsaturated carboxylic acid, a hydroxyl group-containing acrylic monomer, If necessary, other monomers can be reacted by a conventionally known radical copolymerization method, and then the resulting copolymer can be reacted with an amine compound.
[0085]
As another method, an α, β-ethylenically unsaturated carboxylic acid, a hydroxyl group-containing acrylic monomer, and, if necessary, a carboxyl group-containing acrylic resin obtained by copolymerization with another monomer and an epoxy resin are reacted, It can be obtained by a method of reacting an amine compound.
[0086]
Moreover, as a hardening | curing agent, a non-yellowing type block polyisocyanate compound is preferable. Specifically, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate, lysine diisocyanate, etc .; in excess of these polyisocyanate compounds, Terminal isocyanate-containing compounds obtained by reacting low-molecular active hydrogen-containing compounds such as water, ethylene glycol, propylene glycol, trimethylolpropane, hexanetriol, castor oil; burette-type adducts of these polyisocyanate compounds, isocyanuric rings Type adducts, etc. It is also possible to use one of these curing agents as a so-called internal curing agent in which one of these curing agents is bonded to a base resin. It can be used as an external curing agent present in a mixture with a base resin.
[0087]
In addition, as the blocking agent, for example, phenol, lactam, active methylene, alcohol, mercaptan, acid amide, imide, amine, imidazole, urea, carbamate ester, imine, Oxime-based or sulfite-based blocking agents can be used. Among these, lactam-based, alcohol-based and oxime-based blocking agents are particularly preferably used.
[0088]
The component ratio of the base resin and the curing agent is usually in the range of 30 to 100 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the base resin component.
[0089]
Polyester resin cationic electrodeposition paint:
As the polyester resin used as the base resin for the paint, those having a crosslinkable functional group such as a hydroxyl group and a cationic group can be used.
[0090]
Examples of the polyester resin include those obtained by reacting a polyhydric alcohol and a polybasic acid.
[0091]
The polyhydric alcohol is a compound having two or more alcoholic hydroxyl groups in one molecule. For example, ethylene glycol, diethylene glycol, propylene glycol, butanediol, 1,6-hexanediol, pentanediol, 2,2-dimethylpropane Examples include diol, glycerin, trimethylolpropane, pentaerythritol and the like. A polybasic acid is a compound having two or more carboxyl groups in one molecule. For example, phthalic acid, isophthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, adipic acid, sebacic acid, Examples include merit acid, pyromellitic acid, and anhydrides thereof. Furthermore, in the esterification reaction of these polyhydric alcohols and polybasic acids, monobasic alcohols as part of the alcohol component, monobasic acids such as benzoic acid and t-butylbenzoic acid as part of the acid component, as necessary Acids can be used. Polyester resins also include polyester resins modified with oil components such as castor oil, tung oil, safflower oil, soybean oil, linseed oil, tall oil, coconut oil, or fatty acids thereof.
[0092]
As the basic group, one obtained by reacting an epoxy compound such as glycidol with a carboxyl group of a polyester resin and then adding the active hydrogen-containing amine compound can be used.
These polyester resins can have a number average molecular weight generally in the range of 500 to 10,000.
[0093]
The polyester resin can have a hydroxyl value in the range of 10 to 300 mgKOH / g, preferably 20 to 200 mgKOH / g.
[0094]
Moreover, as a hardening | curing agent, the same block polyisocyanate etc. as the above-mentioned acrylic resin cation electrodeposition coating material can be used.
[0095]
The component ratio of the base resin and the curing agent is usually in the range of 30 to 100 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the base resin component.
[0096]
Each of the above cationic electrodeposition paints can be colored with an organic or inorganic color pigment. As these coloring pigments, conventionally known pigments can be used without particular limitation. Specifically, for example, white pigments such as titanium white, zinc white, lithopone, zinc sulfide, and antimony white, black pigments such as carbon black, acetylene black, lamp black, graphite, iron black, and aniline black, ocher, and yellow oxidation Yellow pigments such as iron, naphthol yellow and hansa yellow, orange pigments such as chrome orange and permanent orange, brown pigments such as iron oxide and amber, red pigments such as Bengala, permanent red and quinacridone red pigments, fast violet, methyl violet lake Purple pigments such as ultramarine pigments, blue pigments such as ultramarine blue, bituminous blue, cobalt blue, phthalocyanine blue and phthalocyanine blue, and green pigments such as phthalocyanine green. The blending ratio of the pigment varies depending on the coating color, so it is desirable to set it within the optimum range as appropriate.
[0097]
Cationic electrodeposition paints can be produced by a conventionally known method, and in addition to the above components, a surfactant, a surface conditioner, a curing catalyst, an ultraviolet absorber, an ultraviolet stabilizer and other additives are blended as necessary. can do.
[0098]
The cationic electrodeposition coating is adjusted so that the solid content concentration is about 5 to 25% by weight and the pH is in the range of 5 to 8.
[0099]
Acrylic resin anion electrodeposition paint:
The acrylic resin used as the base resin of the paint is obtained by radical copolymerization reaction of a hydroxyl group-containing (meth) acrylic monomer, α, β-ethylenically unsaturated carboxylic acid, and if necessary, other radical copolymerizable monomers. The radical copolymerization reaction can be performed by a conventionally known method, for example, a solution polymerization method. Examples of the α, β-ethylenically unsaturated carboxylic acid include (meth) acrylic acid and maleic acid. Examples of the hydroxyl group-containing (meth) acrylic monomer and other radical copolymerizable monomers are the same as described above.
[0100]
The acrylic resin usually has a hydroxyl value in the range of 10 to 300 mgKOH / g, preferably 20 to 200 mgKOH / g, an acid value in the range of 20 to 200 mgKOH / g, preferably 30 to 100 mgKOH / g, and the number average molecular weight is 2 In the range of 1,000 to 100,000, preferably in the range of 3,000 to 50,000.
[0101]
As the curing agent, for example, the above-described block polyisocyanate, melamine resin, urea resin, or the like can be used.
[0102]
The component ratio of the base resin and the curing agent is usually in the range of 30 to 100 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the base resin component.
[0103]
Polyester resin anion electrodeposition paint:
As the polyester resin used as the base resin for the paint, those having a crosslinkable functional group such as a hydroxyl group or a carboxyl group can be used.
[0104]
Examples of the polyester resin include those obtained by reacting the same polyhydric alcohol and polybasic acid as described above. Moreover, the above-mentioned monohydric alcohol or monobasic acid can be reacted as necessary.
[0105]
The polyester resin usually has a hydroxyl value in the range of 10 to 300 mgKOH / g, preferably 20 to 200 mgKOH / g, an acid value in the range of 20 to 200 mgKOH / g, preferably 30 to 100 mgKOH / g, and the number average molecular weight is 500. Within the range of 10,000 to 10,000 is appropriate.
[0106]
As the curing agent, for example, the above-described block polyisocyanate, melamine resin, urea resin, or the like can be used.
[0107]
The component ratio of the base resin and the curing agent is usually in the range of 30 to 100 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the base resin component.
[0108]
Each of the anionic electrodeposition paints described above can be colored with an organic or inorganic color pigment described in the cationic electrodeposition paint.
[0109]
Anionic electrodeposition coatings can be produced by a conventionally known method, and in addition to the above components, a surfactant, a surface conditioner, a curing catalyst, an ultraviolet absorber, an ultraviolet stabilizer and other additives are blended as necessary. can do.
[0110]
The anionic electrodeposition coating is adjusted so that the solid content concentration is about 5 to 25% by weight and the pH is in the range of 7 to 10.
[0111]
Using the above-described cationic electrodeposition coating or anion electrodeposition coating, the surface of the metallic material treated with the above-mentioned titanium-based treatment liquid is subjected to cationic electrodeposition coating or anion electrodeposition coating.
[0112]
The cation or anion electrodeposition coating method can be performed by a conventionally known method. Specifically, for example, the bath temperature is 15 to 35 ° C. (preferably 20 to 30 ° C.), voltage: 100 to 400 V (preferably 200 to 300 V), energization time: 30 seconds to 10 minutes, polar area ratio ( A / C) = 8/1 to 1/8, electrode distance 10 to 200 cm, electrodeposition in a stirred state is desirable.
[0113]
The film thickness of the electrodeposition coating film by the electrodeposition paint may be appropriately selected according to the intended performance, but is preferably in the range of 5 to 60 μm, preferably 10 to 40 μm.
[0114]
After electrodeposition coating, in order to remove the extra electrodeposition paint, ultrafiltration filtrate (UF filtrate), RO permeated water, industrial water, pure water, etc., leave the electrodeposition paint on the surface of the paint. If necessary, it can be washed with water.
[0115]
The electrodeposition coating is baked at a coating surface temperature of 110 ° C. to 200 ° C., preferably 140 ° C. to 180 ° C. for 10 minutes to 180 minutes, preferably 20 minutes to 50 minutes. it can.
[0116]
Invention 2:
In the present invention 2, the electrodeposition coating film formed by the method of the present invention 1 or the electrodeposition coating film in the present invention 1 is not baked, that is, the glitter pigment is applied to the surface of the uncured electrodeposition coating film. This is a method for forming a multilayer coating film by painting and baking a colored clear paint to be contained.
[0117]
As a method for applying the colored clear paint on the surface of the above-mentioned uncured electrodeposition coating film, the electrodeposition-coated object is pulled up from the electrodeposition bath, and then set at room temperature or 40 to 110 ° C. Then, after preheating for 10 minutes to 180 minutes, a colored clear paint can be applied (2C1B).
[0118]
Colored clear paint:
As the colored clear paint, a curable paint such as an organic solvent-type paint, a water-based paint, and a powder paint can be used as long as the weather-resistant clear paint.
[0119]
As the resin used in the paint, various resins such as acrylic resin, polyester resin, alkyd resin, silicone resin, and fluororesin can be used. It may be cured by actinic rays such as lines.
[0120]
As the colored clear paint, those used as a top clear paint for automobiles are preferably used, and among them, melamine curable acrylic resin paint, acid curable acrylic resin paint, polyisocyanate curable acrylic resin paint are particularly suitable. Yes. As the acrylic resin used in the melamine curable acrylic resin coating or the polyisocyanate curable acrylic resin coating, for example, the same hydroxyl group-containing acrylic resin as described in the acrylic resin anion electrodeposition coating can be used. As the polyisocyanate compound used in the polyisocyanate curable acrylic resin coating, a non-yellowing type block polyisocyanate compound described in the acrylic resin cationic electrodeposition coating can be used.
[0121]
Examples of the acid curable acrylic resin paint include epoxy group-containing unsaturated monomers (glycidyl (meth) acrylate, allyl glycidyl ether, vinylcyclohexene monooxide, 3,4-epoxycyclohexylmethyl (meth) acrylate, etc.) and the above. A radical copolymer with other radically polymerizable monomer can be used. Examples of the acid curing agent include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, methylcyclohexanetricarboxylic acid, adipic acid, sebacic acid, azelaic acid, hexahydrophthalic acid, hymic acid, succinic acid, methylglutar Examples thereof include acids, pimelic acid, malonic acid, anhydrides thereof, and modified products thereof.
[0122]
In addition, the colored clear paint is a so-called bright pigment such as a metallic pigment or a pearl pigment, such as aluminum flakes, vapor-deposited aluminum thin film, aluminum oxide flakes, mica flakes, titanium oxide-coated mica flakes, iron oxide-coated mica flakes for design. Contains a functional pigment. The addition amount is preferably such that the colored cationic electrodeposition coating film as a base can be seen through, and 0.001 to 5 parts by weight, preferably 0.01 to 2 parts per 100 parts by weight of the total solid content of the colored clear paint. Part by weight, more preferably in the range of 0.02 to 1 part by weight.
[0123]
The above-mentioned colored clear paint containing a luster pigment is applied to the surface of a colored cationic electrodeposition coating film, thereby producing an interference color in the reflected light from the coating film and obtaining an unprecedented novel design. It is done.
[0124]
For example, it is possible to impart a three-dimensional design that has a three-dimensional appearance such as a rainbow color depending on the direction of viewing, such as a glossy feeling or a glittering feeling, or a pearl surface. In particular, a variety of light effects such as fenders, doors, and hoods on the car body produce vivid rainbow colors and unprecedented new design.
[0125]
The colored clear paint is prepared by mixing and dispersing a resin composition and a metallic pigment, and / or a pearl pigment, and an ultraviolet absorber or additive in water or an organic solvent, and has a solid content of 20 to 20 at the time of painting. The viscosity is preferably 60% by weight, preferably 25 to 50% by weight, and the viscosity is adjusted to 10 to 30 seconds / forward cup # 4/20 ° C.
[0126]
The colored clear paint should be applied to the cured or uncured coating surface of the colored electrodeposition paint so that the film thickness is, for example, 15 μm or more, 20 to 70 μm by air spray, airless spray or electrostatic coating. Is preferable, and a multilayer coating film is formed by heating and curing at 80 to 170 ° C. for 10 to 40 minutes.
[0127]
【The invention's effect】
Since the present invention has the above-described configuration, the following effects are exhibited.
[0128]
(1) Since a conventional phosphating treatment solution is not used as the metal surface treatment solution, no sludge is generated by the phosphoric acid compound, so there is no need to treat this sludge as industrial waste and the environment. Excellent in measures and disposal costs.
[0129]
(2) Even if the titanium-based treatment liquid is mixed into the electrodeposition paint bath, which is the next step, there is no risk of adversely affecting the electrodeposition paint or electrodeposition paint. A coating film can be formed.
[0130]
(3) By coating the surface of the electrodeposition coating with a colored clear paint containing a luster pigment to form a multilayer coating, the three-dimensional luster and glitter, and the pearl surface Depending on the viewing direction, it is possible to impart a three-dimensional design with various colors such as rainbow. In particular, a novel design that is not found in the prior art can be obtained depending on the angle of light that strikes parts such as a horizontal part, a vertical part, and a curved surface part of an automobile body such as a hood, a door, and a fender.
[0131]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples.
The present invention is not limited thereby. “Parts” and “%” indicate “parts by weight” and “% by weight”.
[0132]
Production example of titanium-based treatment liquid
Production Example 1
Ammonia water (1: 9) was added dropwise to a solution in which 5 cc of a titanium tetrachloride 60% solution was made 500 cc with distilled water to precipitate titanium hydroxide. After washing with distilled water, 10 cc of a 30% hydrogen peroxide solution was added and mixed to obtain a titanium-based aqueous liquid (A1) containing titanium and having a yellow translucent viscous solid content of 2%.
[0133]
Production Example 2
A mixture of 10 parts of tetraiso-propoxytitanium and 10 parts of iso-propanol was added dropwise to a mixture of 10 parts of 30% hydrogen peroxide and 100 parts of deionized water with stirring at 20 ° C. over 1 hour. Thereafter, aging was carried out at 25 ° C. for 2 hours to obtain a yellow transparent slightly viscous titanium-based aqueous liquid (A2) having a solid content of 2%.
[0134]
Production Example 3
A titanium-based aqueous liquid (A3) having a solid content of 2% was obtained under the same production conditions using tetra-n-butoxytitanium instead of tetraiso-propoxytitanium in the production example of the titanium-based aqueous liquid (A2).
[0135]
Production Example 4
Using a tetraiso-propoxytitanium trimer instead of tetraiso-propoxytitanium in the production example of the titanium-based aqueous liquid (A2), a titanium-based aqueous liquid (A4) having a solid content of 2% was prepared under the same production conditions. Obtained.
[0136]
Production Example 5
In the production example of the titanium-based aqueous liquid (A2), 3 times the amount of hydrogen peroxide solution was added dropwise at 50 ° C. over 1 hour, and further aged at 60 ° C. for 3 hours to obtain a titanium-based aqueous liquid (A5) having a solid content of 2%. Obtained.
[0137]
Production Example 6
The titanium-based aqueous solution (A3) was heat-treated at 95 ° C. for 6 hours to obtain a white-yellow translucent titanium-based aqueous liquid (A6) having a solid content of 2%.
[0138]
Production Example 7
A mixture of 10 parts of tetraiso-propoxytitanium and 10 parts of iso-propanol, 5 parts (solid content) of TKS-203 (manufactured by Teika Co., Ltd.), 10 parts of 30% hydrogen peroxide water, deionized water The mixture was added dropwise to 100 parts of the mixture with stirring at 10 ° C. over 1 hour. Thereafter, the mixture was aged at 10 ° C. for 24 hours to obtain a titanium-based aqueous liquid (A7) having a solid content of 2%, which was yellow and slightly viscous.
[0139]
Production example of cationic electrodeposition paint
Production example of pigment paste A for cationic electrodeposition
After blending 5.88 parts of a tertiary amine-acid neutralized dispersion resin with a solid content of 85% (solid content of 5 parts) and 2.7 parts of 10% acetic acid, 25.8 parts of deionized water was further added and mixed and stirred. did.
Next, 20 parts of titanium white, 16.1 parts of water, 2 parts of bismuth oxide and 1 part of organic tin were blended therein and dispersed for 20 hours in a ball mill to obtain 50% pigment paste A.
[0140]
Cationic power
Production examples of pigment pastes B to D
Pigment pastes B to D were prepared with the blending contents shown in Table 1 in the same manner as for pigment paste A.
[0141]
Table 1
[0142]
[Table 1]

[0143]
Example of production of acrylic resin for cationic electrodeposition coating
246 parts of propylene glycol monomethyl ether was charged into a 2 liter four-necked flask, purged with nitrogen, and kept at 110 ° C.
In this, the mixture shown below was dripped over 3 hours.
25 parts of styrene
18 parts of methyl methacrylate
n-butyl acrylate 6 parts
12 parts of 2-hydroxyethyl methacrylate
PLACCEL FM-3 (trade name, manufactured by Daicel Chemical Industries) 24 parts
15 parts of dimethylaminoethyl methacrylate
Azobisisobutylnitrile 3 parts
One hour after the completion of dropping, a solution prepared by dissolving 8 parts of 2,2′-azobis (2-methylbutyronitrile) in 56 parts of propylene glycol monomethyl ether was added dropwise over 1 hour. After completion of the dropwise addition, this was further maintained at 110 ° C. for 1 hour, and then methyl isobutyl ketone was added to obtain an acrylic resin having a solid content of 75%.
[0144]
Examples of production of curing agents for cationic electrodeposition coatings
50 parts of isophorone diisocyanate (IPDI) was added dropwise to 40 parts of methyl ketoxime at 40 to 60 ° C., and then heated at 80 ° C. for 1 hour to obtain a curing agent for cationic electrodeposition paint having a solid content of 90%.
[0145]
Production example of emulsion for cationic electrodeposition
93.3 parts (solid content 70 parts) of 75% acrylic resin obtained in the above production example, 33.3 parts (solid content 30 parts) of a curing agent for cationic electrodeposition coating, 2.5 parts of liquid organic tin (1 part of solid content) After adding 8.2 parts of 10% formic acid and stirring uniformly, 178.3 parts of deionized water was added dropwise over about 15 minutes with vigorous stirring to obtain a solid content of 32.0%. A cationic electrowear emulsion was obtained.
[0146]
Cationic electrodeposition paint no. Example 1
The prepared 32% cationic electrodeposition emulsion 315.6 parts (solid content 101 parts), 55% pigment paste A 70 parts (38.5 parts), and 311.9 parts pure water were added, and the cation was 20% solids. Electrodeposition paint No. 1 was obtained.
[0147]
Cationic electrodeposition paint no. 2-No. Example 4
In combination as shown in Table 2, the cationic electrodeposition paint No. 2-No. 4 was created.
[0148]
Table 2
[0149]
[Table 2]

[0150]
Anion electrodeposition paint No 1 Example of manufacturing
70 parts (solid content) of an acrylic resin aqueous solution for colored clear paint used in the colored clear paint described below, 30 parts of pigment paste (70 parts (solid content) of an acrylic resin aqueous solution for colored clear paint, and 20 parts of titanium white pigment) Dispersion) 50 parts (solid content), 40 parts (solid content) of a melamine resin aqueous dispersion for colored clear paint described below were blended, and the solid content was adjusted to 20% with deionized water.
[0151]
Production example of colored clear paint
Production example of acrylic resin aqueous solution for colored clear paint
In butyl cellosolve maintained at 115 ° C., 16.7 parts of n-butyl acrylate, 15 parts of methyl methacrylate, 30 parts of styrene, 20 parts of 2-ethylhexyl acrylate, 12 parts of hydroxylethyl methacrylate, 6.3 parts of acrylic acid and azo 1 part of isobutyronitrile was added and the polymerization reaction was carried out under normal conditions. The resulting acrylic resin had an acid value of 50 mgKOH / g, a hydroxyl value of 50 mgKOH / g, and a number average molecular weight of 45,000. Subsequently, the carboxyl group of this acrylic resin was neutralized with dimethylaminoethanol in an equivalent amount to obtain an acrylic resin aqueous solution having a solid content of 55%.
[0152]
Example of manufacturing melamine resin aqueous dispersion for colored clear paint
Melamine 126 parts, 80% paraformaldehyde (manufactured by Mitsui Toatsu Chemicals) 225 parts, n-butanol 592 parts in a 2 liter four-necked flask equipped with a thermometer, stirrer and reflux condenser, 10% caustic soda After adjusting to pH 9.5-10.0 with aqueous solution, it was made to react at 80 degreeC for 1 hour. Thereafter, 888 parts of n-butanol was added, the pH was adjusted to 5.5 to 6.0 with a 5% sulfuric acid solution, and the mixture was reacted at 80 ° C. for 3 hours. After completion of the reaction, neutralize with 20% aqueous caustic soda solution to pH 7.0-7.5, concentrate n-butanol under reduced pressure at 60-70 ° C., and filter to form a hydrophobic melamine resin having a solid content of 27% by weight. Obtained. Nonvolatile content 80%, solvent dilution ratio of water / methanol mixed solvent (weight ratio 35/65) 3.6%, weight average molecular weight 800.
[0153]
This melamine resin is placed in a stirring vessel so that the solid content is 25 parts, and an acrylic resin aqueous solution (50% resin aqueous solution consisting of n-butyl acrylate, methyl methacrylate, styrene, 2-hydroxyethyl methacrylate, acrylic acid) 20 parts, and gradually adding 80 parts of deionized water while stirring with a disperser having a rotational speed of 1000 to 1500 revolutions, and then stirring for another 30 minutes to disperse the water in a 27% solid content melamine resin aqueous dispersion Got.
[0154]
Colored clear paint no. Example 1
163 parts of the acrylic resin aqueous dispersion
131 parts of the melamine resin aqueous dispersion
AQUAZOLE ASE-60 (Note 1) 3 parts
Tinuvin 900 (Note 2) 1 part
Dimethylaminoethanol 0.3 parts
171 parts of deionized water
Aluminum paste 891K (Note 3) 0.5 part
The above mixture was adjusted to a viscosity of 30 seconds (Ford Cup # 4/20 ° C.) with deionized water, and an aqueous clear paint No. 4 having a solid content of 40%. 1 was obtained.
[0155]
Example of manufacturing paste for pearl mica
0.5 parts of pearl mica
1.6 parts of phosphoric acid group-containing acrylic resin
16 parts of cellosolve solvent
After mixing the above components with a disper, 6 parts of the acrylic resin aqueous dispersion was added and further stirred with a disper to obtain a paste for pearl mica.
[0156]
Colored clear paint no. Example 2
24.1 parts of the pearl mica paste
162 parts of the acrylic resin aqueous dispersion
131 parts of the melamine resin aqueous dispersion
AQUAZOLE ASE-60 (Note 1) 3 parts
Tinuvin 900 (Note 2) 1 part
Dimethylaminoethanol 0.3 parts
147 parts deionized water
The above mixture was adjusted to a viscosity of 30 seconds (Ford Cup # 4/20 ° C.) with deionized water, and an aqueous clear paint No. 4 having a solid content of 40%. 2 was obtained.
(Note 1) Aquasol ASE-60: trade name, thickener manufactured by Rohm and Haas.
(Note 2) Tinuvin 900: Ciba Geigy, trade name, UV absorber.
(Note 3) Alpaste 891K: manufactured by Toyo Aluminum Co., Ltd., aluminum content 72%.
(Note 4) Pearl mica white: iron oxide-coated mica, manufactured by Mark, thickness 0.2 to 0.5 μm.
[0157]
Examples and Comparative Examples
Example 1
The titanium-based treatment liquid was applied to an aluminum plate with a bar coater so that the dry film thickness was 0.3 μm, and baked and dried for 3 seconds at a maximum material temperature of 100 ° C. to form a treatment film.
[0158]
Then, cationic electrodeposition paint No. 1 was applied using an electrodeposition coating plate having a dry film thickness of 20 μm, washed with water, and baked at 150 ° C. for 20 minutes.
[0159]
On the coating film, considering the environmental problems, the water-based colored clear paint No. obtained in the production example was used. 1 was coated to a film thickness of 40 μm and baked and dried at 140 ° C. for 20 minutes to obtain a multilayer coating film of Example 1.
[0160]
Examples 2-9
Using the titanium-based treatment liquid listed in Table 3, coating films of Examples 2 to 9 were formed in the same manner as in Example 1.
[0161]
Example 10
In Example 1, the cationic electrodeposition paint No. 1 instead of anionic electrodeposition paint No. 1 A coating film of Example 10 was formed in the same manner as in Example 1 except that 1 was used.
[0162]
Examples 11-13
The coating films of Examples 11 to 13 were formed in the same manner as in Example 1 except that the cationic electrodeposition paint and colored clear paint described in Table 3 were used.
[0163]
Example 14
In Example 11, the cationic electrodeposition paint No. 1 instead of anionic electrodeposition paint No. 1 A coating film of Example 14 was formed in the same manner as Example 11 except that 1 was used.
[0164]
Examples 15 and 16
The titanium-based treatment liquid was applied to an aluminum plate with a bar coater so that the dry film thickness was 0.3 μm, and baked and dried for 3 seconds at a maximum material temperature of 100 ° C. to form a treatment film.
[0165]
Then, cationic electrodeposition paint No. No. 1 or anion electrodeposition paint No. 1 was applied using an electrodeposition coating plate having a dry film thickness of 20 μm, washed with water, and baked at 150 ° C. for 20 minutes.
[0166]
Example 17
The titanium-based treatment liquid was applied to an aluminum plate with a bar coater so that the dry film thickness was 0.3 μm, and baked and dried for 3 seconds at a maximum material temperature of 100 ° C. to form a treatment film.
[0167]
Then, cationic electrodeposition paint No. No. 1 was coated with an electrodeposition coated plate having a dry film thickness of 20 μm, washed with water, and allowed to stand at 20 ° C. for 30 minutes.
[0168]
An aqueous colored clear paint No. obtained in the production example on the coating film. 2 was coated to a film thickness of 40 μm and baked and dried at 140 ° C. for 20 minutes to obtain a multilayer coating film of Example 17.
[0169]
Test results
The performance results of the coating films obtained in Examples 1 to 17 and Comparative Examples 1 to 8 are shown in Tables 3 and 4.
Table 3
[0170]
[Table 3]

[0171]
Table 4
[0172]
[Table 4]

[0173]
(Note 5) Luga Bake Clear: Product name, acrylic resin / amino resin organic solvent type clear paint manufactured by Kansai Paint Co., Ltd.
[0174]
(Note 6) Weather resistance: Cross-cut with a cutter blade on the surface of a test plate that was subjected to an accelerated weather resistance test using a sunshine carbon arc lamp type as defined in JIS K-5400 9.8.1 until the irradiation time reached 1000 hours. The adhesion test was conducted with cellophane tape. ○: Good without problems. (Triangle | delta): A part of crosscut part peels off. X: The coating film is peeled off entirely.
[0175]
(Note 7) Brightness: The appearance of the multilayer coating film was visually evaluated. A: The painted surface has a three-dimensional depth feeling and three-dimensional feeling that is quite metallic or pearly. ○: The paint surface has a metallic or pearly three-dimensional depth and three-dimensional effect. (Triangle | delta): Three-dimensional depth feeling and three-dimensional feeling of metallic tone or pearl tone are hardly seen on the coating surface. X: There is no metallic-like or pearl-like three-dimensional depth feeling and three-dimensional feeling on the coating surface.
(Note 8) 60 ° gloss: 60 ° specular reflectance (%)
(Note 9) Adhesiveness: After dipping the coated plate in warm water at 40 ° C for 10 days, use a knife on the coating surface to make 11 cuts of about 2mm in width and width, and 24mm on the surface. A cellophane adhesive tape having a width was brought into close contact, and the adhesiveness of the gobang eyes when strongly peeled was evaluated according to the following criteria. ○: No peeling at all, Δ: Some peeling, x: Significant peeling
(Note 10) Corrosion resistance: A cross cut reaching the base is put on the painted plate, and after performing a 720 hour salt spray test according to JISZ-2371, it is washed with water, and rust, swelling, etc. of the general part are as follows. While evaluating, the maximum peeling width (one side) of the crosscut part when the cellophane adhesive tape was made to adhere to the crosscut part and it peeled off instantaneously was described. ○: No rust or swelling is observed on the coated surface, Δ: Slight rust or swelling is observed on the coated surface, ×: Significant rust or swelling is observed on the coated surface.
(Note 11) End face coverage: A test plate was prepared by electrodeposition coating on a steel plate having an edge angle of 45 ° under a condition that the cured film thickness of the flat part was 20 μm and curing under a predetermined baking condition. It set to the salt spray apparatus so that the edge part of a test board might become perpendicular | vertical, and the corrosion resistance of the edge part after 168 hours was evaluated by the JIS-Z-2371 salt water humum test. ◎: No rust generated, ○: Slightly generated rust, ×: Extremely rust generated

Claims (5)

Titanium containing titanium obtained by reacting at least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low condensates, titanium hydroxide and titanium hydroxide low condensates with hydrogen peroxide water An electrodeposition coating method comprising coating an acrylic colored electrodeposition paint or a polyester colored electrodeposition paint on the surface of a metallic material of an aluminum material or a steel material treated with a system treatment liquid. The electrodeposition coating method according to claim 1 , wherein the metallic material is an automobile body or an automobile member.  The electrodeposition coating method according to claim 1, wherein the electrodeposition paint is an anionic electrodeposition paint.  The electrodeposition coating method according to claim 1, wherein the electrodeposition paint is a cationic electrodeposition paint. A method for forming a multilayer coating film, comprising: coating a surface of the electrodeposition coating film formed by the method according to any one of claims 1 to 4 with a colored clear paint containing a bright pigment.