简介 |
FIELD : information security.
SUBSTANCE : invention relates to means of protection of documents from forgery, and concerns a marking composition and method of labelling and identifying a valuable document. Composition contains at least one compound of rare-earth metal, a masking substance and an inert carrier. Method of labelling and identifying a valuable document is based on chemical compounds incorporated in said composition, which as a result of reaction with special indicator reagent forms a specific chelate complex, which has no luminescence when excited by UV radiation at room temperature, but reversibly exhibits luminescence at cooling-freezing temperature, which disappears when heated.
EFFECT : marking composition contains at least one compound of rare-earth metal that forms a chelate complex, to identify demanding special conditions, which considerably increases level of protection of valuable document and makes it impossible, challenging and/or unprofitable its forgery.
21 cl, 7 ex |