METHOD FOR PRODUCING A WATER-SOLUBLE PAINT AND VARNISH MATERIAL EXHIBITING PHOTOBACTERICIDAL ACTIVITY FOR APPLYING PHOTOBACTERICIDAL COATINGS BASED ON WATER-SOLUBLE PAINT AND VARNISH MATERIALS AND HYBRID ASSOCIATES OF SILVER SULPHIDE NANOCRYSTALS WITH MOLECULES OF METHYLENE BLUE Russian patent published in 2022 - IPC C09D5/14 C01G5/00 B82Y40/00 

FIELD: paints.

SUBSTANCE: invention relates to the field of producing photobactericidal coatings, more specifically, to methods for modifying water-soluble paint and varnish materials and to a use thereof to form self-sterilising surfaces. Method for producing a water-soluble paint and varnish material exhibiting photobactericidal activity for applying photobactericidal coatings based on water-soluble paint and varnish materials and hybrid associates of silver sulphide nanocrystals with molecules of methylene blue includes blending solutions of thioglycolic acid and silver nitrate while constantly stirring at a speed of 300 to 600 rpm, followed by drip titration with an aqueous solution of NaOH to a pH of 9, adding an aqueous solution of sodium sulphide and further stirring, forming silver sulphide nanocrystals (Ag₂S NC), depositing, centrifuging at a speed of 5,000 rpm for 30 minutes, purifying the resulting Ag₂S NC, adding a 50% aqueous-ethanol solution, and adding a solution of methylene blue in 96% ethanol, resulting in an aqueous-ethanol solution of an antimicrobial composition based on associates of silver sulphide nanoparticles with molecules of methylene blue. The resulting aqueous-ethanol solution of the antimicrobial composition is then added to commercial-grade water-soluble paint and varnish materials on an acrylic or siloxane basis in the ratio of aqueous-ethanol solution of the antimicrobial composition : paint and varnish material equal to 1:10 by weight.

EFFECT: coatings created using the developed material exhibit photobactericidal properties when exposed to light, wherein the photobactericidal effect is preserved on artificially aged samples imitating the 1-year use of the coatings.

1 cl, 2 dwg, 3 ex