METHOD FOR OBTAINING A WATER-INSOLUBLE PATTERN Russian patent published in 2021 - IPC B41M3/00 

FIELD: security features.

SUBSTANCE: application: to produce a water-insoluble pattern on the substrate and/or inside it. The essence of the invention is that the production of a water-insoluble pattern on the substrate and/or inside it includes the following steps: a) production of the substrate, b) production of processing composition A, including a spreading salt, c) production of processing composition B, including an acid or its salt, while the spreading salt of processing composition A and the acid or its salt of processing composition B are selected so that the cation of the spreading salt and the anion of the acid or its salt are able to form a water-insoluble salt in a water environment, and d) application of processing composition A and processing composition B to at least one area of the substrate surface to form at least one water-insoluble pattern on the substrate and/or inside it, with processing composition A and processing composition B at least partially contact with each other and are applied simultaneously or sequentially in any order, while the water-insoluble pattern is a hidden image that is invisible when viewed from the first angle relative to the surface of the substrate, and visible when viewed from the second angle relative to the surface of the substrate.

EFFECT: providing the capability to create a drawing that makes it possible to easily and directly confirm authenticity.

21 cl, 16 dwg