EP 0058711 B1 19840613 - PROCESS AND PRODUCT FOR THE PASSIVATION OF IRON AND STEEL SURFACES
Title (en)
PROCESS AND PRODUCT FOR THE PASSIVATION OF IRON AND STEEL SURFACES
Publication
Application
Priority
DE 3032226 A 19800827
Abstract (en)
[origin: WO8200665A1] Metal surfaces are treated with 0,5 to 5% by weight of aqueous solutions (pH 7.5 to 10.5) containing a combination of anticorrosive substances giving a clear aqueous solution. This combination includes: a) one or several alkylamides of n-monomaleic or isomaleic acid with 6 to 14, preferably 8 to 10 carbon atoms. b) one or several alkanolamines, preferably mono-, di and/or triethanolamine and c) complexing phosphonic oxides, preferably 1-hydroxy-alkyl-1, 1-diphosphonic oxyde, 1-aminoalkyl-1 acid, 1-diphosphonic, phosphonocarbonic acid and/or a phosphonic acid having the formula: (FORMULA) Preferred phosphonic acids are 1-hydroxyethane-1, 1-diphosphonic, 2-phosphonobutane-1,2,4-tricarbonic and/or nitrilotrimethylenphosphonic acid. The ratio a:b in the solutions has to be from 1:0,3 to 1:10, the ratio a:c has to be from 1:0.01 to 1:0,5. The solutions may further contain surfactants, preferably phosphates and/or borates. These solutions provide a better protection against corrosion than that obtained with the means used heretofore.
IPC 1-7
IPC 8 full level
C23C 22/62 (2006.01); C23F 11/10 (2006.01); C23F 11/14 (2006.01); C23F 11/16 (2006.01)
CPC (source: EP US)
C23F 11/10 (2013.01 - EP US)
Designated contracting state (EPC)
AT DE GB NL SE
DOCDB simple family (publication)
WO 8200665 A1 19820304; BE 890068 A 19811216; BR 8108760 A 19820706; CA 1169337 A 19840619; DE 3032226 A1 19820401; DE 3164174 D1 19840719; EP 0058711 A1 19820901; EP 0058711 B1 19840613; ES 504978 A0 19820816; ES 8206660 A1 19820816; FR 2489372 A1 19820305; FR 2489372 B1 19860411; IT 1137644 B 19860910; IT 8123630 A0 19810825; JP H0132313 B2 19890630; JP S57501289 A 19820722; MX 157164 A 19881031; US 4437898 A 19840320; ZA 815967 B 19820929
DOCDB simple family (application)
EP 8100128 W 19810819; BE 205753 A 19810825; BR 8108760 A 19810819; CA 383308 A 19810806; DE 3032226 A 19800827; DE 3164174 T 19810819; EP 81902484 A 19810819; ES 504978 A 19810826; FR 8116392 A 19810827; IT 2363081 A 19810825; JP 50286281 A 19810819; MX 18889781 A 19810826; US 36502582 A 19820405; ZA 815967 A 19810827