CHROMIUM-FREE COATING COMPOSITION WITH ANTI-CORROSION EFFECT FOR METAL SUBSTRATES Russian patent published in 2021 - IPC C09D5/08 C09D163/00 C09D7/63 C08K5/39 C23C22/05 C23C22/48 C23C28/00 

FIELD: anti-corrosion compositions.

SUBSTANCE: invention relates to an aqueous chromium-free coating composition, a method for at least partial coating metal substrate with a primer layer, a method for at least partial coating metal substrate with a multilayer coating, the use of a coating composition for corrosion protection of metal substrates and a metal substrate coated at least partially with a coating composition. The aqueous chromium-free coating composition includes: (A) at least one binder containing (A1) at least one synthetic resin and (A2) at least one crosslinking agent. Additionally, the composition contains (B) at least one complex compound iron(III)-tris(N,N-dithiocarbamate) selected from a group consisting of the following compounds: iron(III)-tris(dimethyldithiocarbamate), iron(III)-tris(diethyldithiocarbamate) and iron(III)-tris(pyrrolidine dithiocarbamate). The water content in the coating composition is at least 50.0 wt.% by the total content of liquid diluents present in the coating composition.

EFFECT: production of chromium-free primer coating compositions that are suitable for coating metal substrates, in particular metal substrates in the field of aircraft production, such as aluminum and aluminum alloys, capable of replacing usual chromium-based coating compositions and providing more economical and environmentally friendly coating process compared to traditionally used chromium-based coating compositions, having the required anti-corrosion effect to at least the same extent as the usual chromium-based industrial standard.

11 cl, 9 tbl