Patent · US Expired

Removal of acid from cathodic electrocoating baths by electrodialysis

US5114554A · kind A · utility

7Cited by

7References

10Claims

0Family size

Assignee

BASF SE

Inventors

Hartwig Voss · Bischofswerda, DE
Thomas Bruecken · Dortmund, DE

Key dates

Filing date	Dec 1, 1988
Grant date	May 19, 1992
Priority date	—
Expiry date	Dec 1, 2008

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S204/13
WIPO fieldChemical engineering
WIPO sectorChemistry

Abstract

Acid is removed from cathodic electrocoating baths in which electroconductive substrates are being coated with cationic resins present in the form of aqueous dispersions, at least a portion of the coating bath being subjected to an ultrafiltration where the ultrafiltration membrane retains the cationic resin to form an ultrafiltrate which contains water, solvent, low molecular weight substances and ions and is at least partly recycled into the coating bath, by subjecting at least a portion of the ultrafiltrate to a specific electrodialysis treatment before returning it into the electrocoating bath.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.