METHOD FOR PRODUCT AUTHENTICITY CONTROL Russian patent published in 2021 - IPC G07D7/00 

FIELD: products protection.

SUBSTANCE: invention relates to methods for protecting products from counterfeiting and is intended to determine the authenticity of products using technical means. A protective agent is formed on the product by applying on it at least one control mark containing nanosized cellulose particles, metal nanoparticles with a particle size of 15 to 100 nm, selected from the group: gold nanoparticles, silver nanoparticles, nanoparticles of an alloy of gold and silver, nanoparticles consisting of a gold core and a silver shell, nanoparticles consisting of a silver core and a gold shell, mixtures of any of these nanoparticles, and exhibiting the properties of surface plasmon resonance at a wavelength selected from the range from 400 to 2000 nm, at least two coding organic substances previously adsorbed on metal nanoparticles, related to Lewis bases, having high polarizability and characterized by different Raman spectra and a protective additive having the property of photoluminescence or elastic light scattering when irradiated at a wavelength in the range from 400 to 2000 nm, which differs from the wavelength of the surface plasmon resonance of the metal nanoparticles used. Each control mark with a certain quantitative composition is assigned to a certain specific symbol and a combination of symbols with a given sequence is formed, corresponding to the designation of the item under test. Then, after the operation of the product, the control marks are read by their irradiation with monochromatic electromagnetic radiation at the wavelength of the surface plasmon resonance of the metal nanoparticles used with simultaneous registration of the giant Raman spectra of each of the applied control marks, by which their quantitative compositions are determined. The latter are compares with the quantitative compositions of the applied control marks corresponding to specific symbols. Then the correspondence of the received sequence of symbols with the designation of the item under test is checked, and if the received sequence of characters coincides with the designation of the item under test, a conclusion is made about the authenticity of the item under test.

EFFECT: invention ensures the stability of protection over time, protecting control marks from wear and contamination during the operation of products, increases the number of evaluative features by optimizing the composition of the protective agent applied to the product, while reduces the possibility of counterfeiting, copying and changing.

1 cl, 1 dwg