EP 0898621 B1 19991103 - PROCESS FOR REMOVING SOAP-CONTAMINATED CONVERSION LAYERS ON METAL WORKPIECES
Title (en)
PROCESS FOR REMOVING SOAP-CONTAMINATED CONVERSION LAYERS ON METAL WORKPIECES
Title (de)
VERFAHREN ZUM ENTFERNEN VON MIT SEIFEN BEHAFTETEN KONVERSIONSSCHICHTEN VON METALLISCHEN WERKSTÜCKEN
Title (fr)
PROCEDE POUR ELIMINER DES COUCHES DE CONVERSION ALTEREES PAR DES SAVONS, SUBSISTANT SUR DES PIECES METALLIQUES
Publication
Application
Priority
- DE 19618899 A 19960510
- EP 9701966 W 19970418
Abstract (en)
[origin: DE19618899A1] In a process for removing soap-contaminated conversion layers on metal workpieces remaining after cold-forming, cleaning is effected with a cleaning agent containing dilute nitric, phosphoric and/or amidosulphonic acid at a temperature of above 60 DEG C, the cleaning agent is cooled after sufficiently high load in the absence of the cleaned workpieces to a temperature below 55 DEG C, the fatty acid layer floating up is separated and at least the greater portion of the aqueous phase is re-used for cleaning. Preferred embodiments of the invention include the re-use for cleaning of the aqueous phase by adjusting the active cleaning components to the nominal concentration, cleaning with a cleaning agent containing a tenside, especially alkyl amine ethoxlylate, and applying the process to the cleaning of soapy calcium aluminate coatings remaining on workpieces of aluminium or aluminium alloys after cold-forming.
IPC 1-7
IPC 8 full level
CPC (source: EP US)
C23G 1/125 (2013.01 - EP US); C23G 1/36 (2013.01 - EP US)
Designated contracting state (EPC)
DE FR IT
DOCDB simple family (publication)
DE 19618899 A1 19971113; AU 2699897 A 19971205; CA 2254846 A1 19971120; DE 59700669 D1 19991209; EP 0898621 A1 19990303; EP 0898621 B1 19991103; US 6153015 A 20001128; WO 9743462 A1 19971120
DOCDB simple family (application)
DE 19618899 A 19960510; AU 2699897 A 19970418; CA 2254846 A 19970418; DE 59700669 T 19970418; EP 9701966 W 19970418; EP 97920718 A 19970418; US 20201698 A 19981208