JP2011106029A5 - - Google Patents

Description

また、本発明のインヒビター成分（ｄ）において、チタン弗化水素酸（Ｈ）とジルコニウム弗化水素酸（Ｉ）の両方を含有する場合、その配合比に関して、チタン弗化水素酸（Ｈ）に含まれるＴｉ量（Ｍ_Ｈ）とジルコニウム弗化水素酸（Ｉ）に含まれるＺｒ量（Ｍ_Ｉ）の金属成分質量比〔（Ｍ_Ｈ）／（Ｍ_Ｉ）〕が０．５〜０．８である必要があり、０．６〜０．８であることがより好ましく、０．６〜０．７であることがもっとも好ましい。当該金属成分質量比〔（Ｍ_Ｈ）／（Ｍ_Ｉ）〕がこの範囲にあると、チタン弗化水素酸より生成する相対的に加工性は高いが耐アルカリ性の低いチタン若しくはその酸化物皮膜と、相対的に硬く脆いが耐アルカリ性の高いジルコニウム若しくはその酸化物の存在割合が適正となり、素材の塑性変形に付随した皮膜の変形に対して追従性が高まり、皮膜欠陥が生じにくく耐食性が低下しにくくなるため好ましい。逆に０．８を超えると、相対的に耐アルカリ性の低いチタン若しくはその酸化物皮膜の存在割合が多くなるため、皮膜の耐アルカリ性が低下し、耐食性が低下するため好ましくない。 In addition, when the inhibitor component (d) of the present invention contains both titanium hydrofluoric acid (H) and zirconium hydrofluoric acid (I), regarding the blending ratio, titanium hydrofluoric acid (H) The metal component mass ratio [(M _H ) / (M _I )] of the amount of Ti contained (M _H ) and the amount of Zr (M _I ) contained in zirconium hydrofluoric acid (I) is 0.5 to 0.8. It is more preferable that it is 0.6-0.8, and it is most preferable that it is 0.6-0.7. When the metal component mass ratio [(M _H ) / (M _I )] is within this range, titanium or its oxide film having relatively high workability but low alkali resistance produced from titanium hydrofluoric acid The proportion of zirconium or its oxide, which is relatively hard and brittle but has high alkali resistance, is appropriate, and the followability to the deformation of the film accompanying the plastic deformation of the material is increased, so that the film defect is less likely to occur and the corrosion resistance is reduced. Since it becomes difficult, it is preferable . On the other hand , if it exceeds 0.8, the proportion of titanium or its oxide film having a relatively low alkali resistance increases, so that the alkali resistance of the film is lowered and the corrosion resistance is lowered.

耐アルカリ性
皮膜形成後、シリケート系アルカリ脱脂剤のパルクリーンＮ３６４Ｓ（日本パーカライジング（株）製）を用いて、濃度２０ｇ／Ｌ、温度６０℃の条件で２分間スプレー処理し、ＪＩＳ−Ｚ−２３７１による塩水噴霧試験を１２０時間行い、白錆発生状況を観察した。
＜評価基準＞
◎◎＝錆発生が全面積の０％
◎＝錆発生が全面積の０％を超え、３％未満
○＝錆発生が全面積の３％以上１０％未満
△＝錆発生が全面積の１０％以上３０％未満
×＝錆発生が全面積の３０％以上 After alkali resistance film formed by using a pulse clean N364S silicate-based alkali degreasing agent (manufactured by Japan Parkerizing Co.) was sprayed for 2 minutes under conditions of a concentration 20 g / L, temperature 60 ℃, JIS-Z-2371 A salt spray test was conducted for 120 hours, and the occurrence of white rust was observed.
<Evaluation criteria>
◎◎ = Rust generation is 0% of the total area
◎ = Rust generation exceeds 0% of total area and less than 3% ○ = Rust generation is 3% or more and less than 10% of total area △ = Rust generation is 10% or more and less than 30% of total area × = Rust generation is all More than 30% of the area