Global Patent Index - EP 1002143 A1

EP 1002143 A1 20000524 - ALKALINE STRIP PASSIVATION

Title (en)

ALKALINE STRIP PASSIVATION

Title (de)

ALKALISCHE BANDPASSIVIERUNG

Title (fr)

PASSIVATION ALCALINE DE BANDE

Publication

EP 1002143 A1 (DE)

Application

EP 98942626 A

Priority

  • DE 19733972 A
  • EP 9804670 W

Abstract (en)

[origin: DE19733972A1] The invention relates to a method for the alkaline passivation of galvanised and alloy-galvanised steel surfaces and of aluminium in strip plants. According to the invention, the metal surfaces are brought into contact with an alkaline aqueous solution containing complexers and iron, said solution having a free alkalinity level of between 5 and 20 points and an overall alkalinity level of between 7 and 30 points and containing 0.1 to 1 g/l magnesium ions, 0.1 to 1 g/l iron (III) ions and 0.5 to 5 g/l amino or hydroxycarboxylate ions. A repassivation with or without chromium can then be carried out.

IPC 1-7

C23C 22/60; C23C 22/66; C23C 22/83

IPC 8 full level

C23C 22/62 (2006.01); C23C 22/66 (2006.01)

CPC (source: EP)

C23C 22/34 (2013.01); C23C 22/60 (2013.01); C23C 22/66 (2013.01); C23C 22/73 (2013.01); C23C 22/83 (2013.01)

Citation (search report)

See references of WO 9907917A1

Designated contracting state (EPC)

BE DE ES FR GB IT SE

DOCDB simple family (publication)

DE 19733972 A1 19990211; AR 015142 A1 20010418; AU 730256 B2 20010301; AU 9069398 A 19990301; CA 2300275 A1 19990218; EP 1002143 A1 20000524; EP 1002143 B1 20020403; ES 2175763 T3 20021116; US 6346295 B1 20020212; WO 9907917 A1 19990218; ZA 9807032 B 19990208

DOCDB simple family (application)

DE 19733972 A 19970806; AR P980103868 A 19980805; AU 9069398 A 19980725; CA 2300275 A 19980725; EP 9804670 W 19980725; EP 98942626 A 19980725; ES 98942626 T 19980725; US 48527500 A 20000405; ZA 9807032 A 19980805