| 摘要 |
PURPOSE:To meka it possible to form a homogenous grain reduced in an etching amount by chemically treating the surface of an aluminum plate within a short time, by using an aqueous solution containing ferric chloride and phosphoric acid as an etching solution. CONSTITUTION:An aluminum plate, of which the surface was cleaned, is chemically grained by using an aqueous solution containing ferric chloride and phosphoric acid as an etching solution. The concn. of ferric chloride contained in the etching solution is selected from a range of 20-60wt% and that of phosphoric acid from a range of 40-70wt%. The treatment condition of chemical graining is within a range wherein average center line roughness (Ra) is 0.3-1.0mum and it is advantageous to select said condition from such a range that the temp. of the etching solution is 20-100 deg.C and the treating time thereof is 5- 120sec. As a treating means, a method for immersing the aluminum plare in the bath of the etching solution or one for spraying the etching solution to the surface of the aluminum plate is used. Because smut is generated on the surface of the aluminum plate, desmutting treatment is performed for 1-300sec at 20- 100 deg.C by using a 0.5-40wt% aqueous alkali solution. |
