EP 0224065 B1 19890118 - PROCESS FOR OBTAINING CHROMATE LAYERS
Title (en)
PROCESS FOR OBTAINING CHROMATE LAYERS
Publication
Application
Priority
JP 24406385 A 19851101
Abstract (en)
[origin: JPS62107096A] PURPOSE:To obtain a uniform film having superior corrosion resistance, sticking power and adhesion to a paint film by cathodically electrolyzing the surface of a galvanized steel sheet in a treating soln. contg. Cr<6+>, CR<3+>, silica, silicate and NO3<-> each at a specified concn. and having a specified ratio of Cr<6+>/Cr<3+>. CONSTITUTION:The surface of a galvanized steel sheet is cathodically electrolyzed in a treating soln. contg. 5-70g/l Cr<6+>, 0.01-5.0g/l Cr<3+>, 5-100g/l silica and/or silicate and 0.05-10g/l NO3<-> and having 1/50-1/3 ratio of Cr<6+>/Cr<3+>. Chromic anhydride, Cr (III) nitrate and nitric acid may be used as sources for the Cr<6+>, Cr<3+> and NO3<->, respectively. The preferred pH of the treating soln. is 1-6 and the temp. is ordinary temp. - 70 deg.C. The preferred amount of Cr deposited is about 10-300mg/m<2> and that of silica is about 3-30mg/m<2> (expressed in terms of Si).
IPC 1-7
IPC 8 full level
C25D 11/38 (2006.01)
CPC (source: EP US)
C25D 11/38 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE DE FR IT NL SE
DOCDB simple family (publication)
EP 0224065 A1 19870603; EP 0224065 B1 19890118; AT E40158 T1 19890215; AU 583431 B2 19890427; AU 6427586 A 19870507; CA 1311714 C 19921222; DE 3636797 A1 19870507; DE 3661846 D1 19890223; JP H0124880 B2 19890515; JP S62107096 A 19870518; NZ 217984 A 19881129; US 4756805 A 19880712; ZA 867143 B 19870429
DOCDB simple family (application)
EP 86115014 A 19861029; AT 86115014 T 19861029; AU 6427586 A 19861022; CA 521583 A 19861028; DE 3636797 A 19861029; DE 3661846 T 19861029; JP 24406385 A 19851101; NZ 21798486 A 19861017; US 91840986 A 19861014; ZA 867143 A 19860919