CHROMIUM- AND PHOSPHATE-FREE COATING FOR ELECTRICALLY INSULATING AN ELECTRIC STRIP

• Main Authors: Arnold, Andreas, Hochstrate, Ramona, Geick, Volker, Bryden, Todd, de Zeeuw, Ard
• Format: Patent
• Language: English
• Published: 24.09.2020
• Subjects: ADHESIVES; BASIC ELECTRIC ELEMENTS; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; CORRECTING FLUIDS; DYES; ELECTRICITY; FILLING PASTES; INDUCTANCES; INKS; MAGNETS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; USE OF MATERIALS THEREFOR; WOODSTAINS

The present invention relates to a method for providing electrically insulating and anti-corrosive coatings on electrical steel strip by using a phosphate-free aqueous dispersion. Furthermore, the invention relates to such an aqueous dispersion which is particularly suitable for providing electrically insulating and anti-corrosive coatings on electrical steel strip. The aqueous dispersion of the present invention is substantially free of phosphates and organic compounds and comprises silicates dissolved in water as an inorganic binder which forms the coating, and a mixture of oxide pigments of the elements titanium and aluminum. The subject matter of the invention also comprises a laminated electrical steel strip which is made from the electrical steel strip produced in the method according to the invention or from electrical steel strip coated with an aqueous dispersion according to the invention.