PREPARATION AND PROCESSING METHOD OF STEEL BACKPLATE Russian patent published in 2017 - IPC C23C22/34 C23C22/80 C23C22/83 

FIELD: metallurgy.

SUBSTANCE: method for preparing and preprocessing of the metal backplate, including the contacting of at least the part of the backplate with the conditioning composition, containing the source of free fluoride, at that the pH value of the conditioning composition is in the range of 2.5 up to 5, the conditioning composition, substantially free of phosphate ions, and when contacting with the substrate, the conditioning composition activates the surface for better reaction at subsequent coating application steps and removes the oxide layers, when the oxide layers are at the backplate surface, and the preprocessing composition application, containing the metal from group IIIB and/or group IVB to at least the part of the backplate, contacted to the indicated conditioning composition. While contacting the backplate, the preprocessing composition reacts and chemically changes the surface of the substrate and binds to it, forming the protective layer.

EFFECT: receipt of the corrosion resistant metal substrates, thus allows to avoid the environmental problems, associated with the chromates or high levels phosphates use.

23 cl, 5 tbl, 5 ex