FLAT STEEL PRODUCTS WITH MULTI-LAYER PROTECTIVE COATING Russian patent published in 2022 - IPC C23C28/00 C25D3/22 

FIELD: polymer coatings.

SUBSTANCE: invention relates to protective multifunctional corrosion and chemical resistant polymer coatings on galvanized steel flat products. The flat rolled steel with a multilayer protective coating contains a zinc galvanic layer, made on both sides of the flat rolled product, a passivation layer, made on the surface of the zinc plating layer on both sides of the mentioned rolled product, a primer layer, made on the surface of the passivating layer on both sides of the said rolled product, and a layer a protective polymeric material based on polyvinylidene fluoride, made over a primer layer on the front side of steel flat products. Zinc electroplated layer additionally contains from 2 to 20 wt.% Ni, its thickness is from 4 to 12 mcm on each side. The difference in thickness of each zinc galvanized layer and layers among themselves does not exceed 20%. The passivating layer is made 1-2 mcm thick. The primer layer is made on the basis of polyester or polyurethane resin with a thickness of 5-15 microns. The layer of protective polymer material on the front side is made on the basis of a polymer composition containing from 85 to 90 wt.% polyvinylidene fluoride and has a thickness of 20-35 microns. On the reverse side of the primer layer, a protective layer 5-25 mcm thick is made based on epoxy resin.

EFFECT: expansion of the arsenal of technical means of double-sided protective coatings of steel flat products due to the production of flat steel products with a multilayer protective coating, which makes it possible to obtain high corrosion and chemical resistance along with the implementation of a combination of consumer properties with high values ​​of technical characteristics.

1 cl, 8 ex