METHOD OF MARKING THE OBJECT IN ANTI-COUNTERFEIT PROTECTION AND PHOTOCHROME INK Russian patent published in 2018 - IPC B41M3/00 

FIELD: printing industry; chemistry.

SUBSTANCE: invention relates to methods for identifying an object. Method of marking an object in anti-counterfeit protection involves applying a photosensitive identification mark based on bacteriorhodopsin in a mixture with an aqueous solution of a polymer binder by piezoelectric inkjet printing, followed by obtaining an optical effect by means of an additional external action, photochromic ink further comprising a water retention component, a humectant and a surfactant, and bacteriorhodopsin is used as fragments of purple membranes 25÷250 nm size, obtained after ultrasonic treatment of a suspension of purple membranes, with the following ratio of components, mass parts: bacteriorhodopsin 1÷5; water 40÷85; polymer binder (polyvinyl alcohol, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, hydroxyethylcellulose) 1÷10, water-retaining component (glycerin) 4÷15, surfactant (Triton-X100, Igepal CO-520) 0.1÷2.0. In addition, photochromic ink contains an additional solvent in the form of polyhydric alcohol, a corrosion inhibitor, an ultraviolet adsorber, a preservative, an alkaline bacteriorhodopsin properties modifier.

EFFECT: invention can be used to improve the security of anti-counterfeit protection and to control the authenticity of various valuable documents and articles using a photosensitive identification mark based on bacteriorhodopsin.

15 cl, 7 ex