PURPOSE: To obtain a film forming soln. for the aluminum DI can and tin DI can by specifying the composition of the soln. for treating the surface of the DI can before being coated and printed.
CONSTITUTION: At least one kind between a zirconium compd. and a titanium compd. is added to phosphate ion to control the pH to 2.0-4.0. An oxidizing agent by ≤500ppm and ≤2000ppm of at least one kind between hydrofluoric acid and a fluoride as fluorine are added to obtain a surface-treating soln. The aluminum DI can and tin DI can degreased and washed with water are coated with a film. In this case, the can is previously treated with the surface- treating soln. by spraying or dipping at a room temp. to 50°C for 2 to 120sec. Consequently, excellent corrosion resistance and coating adhesion are obtained.
AOKI TOMOYUKI
YOSHIDA MASAYUKI
