Chemical conversion coated plated steel sheet and method for producing same

A method of preparing a chemically treated aluminum-based plated steel sheet, the method comprising:

• preparing an aluminum-based alloy plated steel sheet, the aluminum-based alloy including 85-99% by weight of aluminum;
• and
• forming a chemical conversion film that has a thickness 0.5-10 μm, by coating and drying a chemical treatment solution on a surface of the aluminum-based alloy plated steel sheet, wherein:
• the chemical treatment solution contains a fluororesin and at least one selected from the group consisting of an oxoate, a fluoride, a hydroxide, an organic salt, a carbonate and a peroxygenated salt of a group 4A metal, the fluororesin containing a total of 0.05-5% by weight of a hydrophilic functional group selected from the group consisting of a carboxyl group, a sulfonic acid group and a salt thereof, and 7-20% by weight of a fluorine atom, the fluororesin having a number-average molecular weight of 1,000-2,000,000;
• and
• the total amount of the oxoate, the fluoride, the hydroxide, the organic salt, the carbonate and the peroxygenated salt of the group 4A metal is within a range of 0.1-5% by weight, in terms of the group 4A metal, with respect to the fluororesin.