摘要 |
FIELD: printing engineering. ^ SUBSTANCE: paper is protected by introducing chemical reagents into paper and into paint applied over the paper surface. The reagents are selected in a way that they interact with each other in presence of corresponding authenticity indicator in producing colored reaction products at the places the paper and paint contact each other. Any of chemical reagents alone does not react with the indicator with colored compounds being produced. ^ EFFECT: high difficulty in discovering reagent complex used; reduced protection costs. ^ 9 cl, 7 dwg
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