MULTI-LAYER COMPOSITE ELEMENT BASED ON PAPER AND VALUABLE COUNTERFEIT-PROOF DOCUMENT Russian patent published in 2015 - IPC D21H21/44 B42D25/21 B42D25/333 B42D25/36 

FIELD: textiles, paper.

SUBSTANCE: invention relates to production of paper with special characteristics, in particular for forms of valuable securities. The compositions of the base layer and the additional layer have either different optical density in the infrared (IR) band of the optical spectrum corresponding to the wavelength of 0.7 to 2.5 microns, but at the same time, the equal optical density on at least one part of the visible range of the optical spectrum, or the compositions of the said layers have equal optical density in the IR band of the spectrum, but at the same time are different in optical density in the visible band of the spectrum.

EFFECT: composite protective element based on paper is proposed, comprising a layer of a base material and at least one additional layer, which comprise watermarks.

20 cl, 6 dwg