EP 0646187 B1 20010110 - NON-CHROMATED OXIDE COATING FOR ALUMINUM SUBSTRATES
Title (en)
NON-CHROMATED OXIDE COATING FOR ALUMINUM SUBSTRATES
Title (de)
NICHT-CHROMATIERTE OXIDÜBERZÜGE FÜR ALUMINIUMSUBSTRATE
Title (fr)
COUCHE D'OXYDE NON CHROMATE POUR SUBSTRATS EN ALUMINIUM
Publication
Application
Priority
- EP 9301630 W 19930623
- US 90385392 A 19920625
- CN 93101737 A 19930118
Abstract (en)
[origin: WO9400619A1] (A) A process for forming a cobalt conversion coating on a metal substrate, thereby imparting corrosion resistance and paint adhesion properties. The invention was developed as a replacement for the prior art chromic acid process. The process includes the steps of: (a) providing a cobalt conversion solution comprising an aqueous solution containing a soluble cobalt-III hexavalent complex, the concentration of the cobalt-III hexavalent complex being from about 0.01 mole per liter of solution to the solubility limit of the cobalt-III hexavalent complex; and (b) contacting the substrate with the solution for a sufficient amount of time, whereby the cobalt conversion coating is formed. The substrate may be aluminum or aluminum alloy, as well as Cd plated, Zn plated, Zn-Ni plated, and steel. The cobalt-III hexavalent complex may be present in the form of Mem(Co(R)6)n, wherein Me is Na, Li, K, Ca, Zn, Mg, or Mn, and wherein m is 2 or 3, n is 1 or 2, and R is a carboxylate having from 1 to 5 C atoms. (B) A chemical conversion coating solution for producing the cobalt conversion coating on a metal substrate, the solution including an aqueous solution containing a soluble cobalt-III hexavalent complex, the concentration of the cobalt-III hexavalent complex being from about 0.01 mole per liter of solution to the solubility limit of the cobalt-III hexavalent complex. (C) A coated article exhibiting acceptable corrosion resistance and paint adhesion properties, the article including: (a) a metal substrate; and (b) a cobalt conversion coating formed on the substrate, the cobalt conversion coating including aluminum oxide Al2O3 as the largest volume percent, and cobalt oxides CoO, Co2O3, and Co3O4.
IPC 1-7
IPC 8 full level
C23C 22/56 (2006.01); C23C 22/66 (2006.01); C23C 22/68 (2006.01)
CPC (source: EP)
C23C 22/56 (2013.01); C23C 22/66 (2013.01); C23C 22/68 (2013.01)
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
WO 9400619 A1 19940106; AT E198631 T1 20010115; AU 4500893 A 19940124; AU 687740 B2 19980305; BR 9306602 A 19981208; CA 2138790 A1 19940106; CA 2138790 C 20041019; CN 1080963 A 19940119; CN 1090338 A 19940803; CN 1138873 C 20040218; CN 1195893 C 20050406; DE 69329853 D1 20010215; DE 69329853 T2 20010426; DK 0646187 T3 20010430; EP 0646187 A1 19950405; EP 0646187 B1 20010110; ES 2152950 T3 20010216; GR 3035554 T3 20010629; JP 3345010 B2 20021118; JP H07508311 A 19950914; MX 9303745 A 19940228; NO 315522 B1 20030915; NO 945026 D0 19941223; NO 945026 L 19950224; NZ 253699 A 19970526; RU 2135637 C1 19990827; RU 94046218 A 19961020; SG 43169 A1 19971017; ZA 934544 B 19940318
DOCDB simple family (application)
EP 9301630 W 19930623; AT 93914728 T 19930623; AU 4500893 A 19930623; BR 9306602 A 19930623; CA 2138790 A 19930623; CN 93101737 A 19930118; CN 93107583 A 19930625; DE 69329853 T 19930623; DK 93914728 T 19930623; EP 93914728 A 19930623; ES 93914728 T 19930623; GR 20010400395 T 20010309; JP 50204994 A 19930623; MX 9303745 A 19930622; NO 945026 A 19941223; NZ 25369993 A 19930623; RU 94046218 A 19930623; SG 1996004772 A 19930623; ZA 934544 A 19930624