To provide a chromium-free surface-treated steel sheet having excellent corrosion resistance both in a plate portion and after working, even in the case of being subjected to alkali degreasing by users or exposed to a corrosive environment over a long period.
On the surface of a galvanized steel sheet or an aluminum base plated steel sheet, a surface treatment film is formed from a surface treatment composition obtained by compounding an organic phosphoric acid compound and an inorganic phosphoric acid compound to a titanium based aqueous liquid obtained by mixing a specified titanium compound with a hydrogen peroxide solution at a prescribed ratio, and further, the upper layer thereof has an upper layer film formed by applying a coating material composition composed of a specified high molecular weight epoxy group-containing resin, and performing drying.
KUBOTA TAKAHIRO
NAKANO TAKASHI
KANSAI PAINT CO LTD
| JP2008248356A | 2008-10-16 | |||
| JP2003193088A | 2003-07-09 | |||
| JP2003193255A | 2003-07-09 | |||
| JP2000160353A | 2000-06-13 | |||
| JP2006082369A | 2006-03-30 |
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