POLYMER SANDWICH ELEMENT FOR PAPER, WHICH HAS OPTICALLY VARIABLE EFFECT Russian patent published in 2014 - IPC D21H21/44 B42D25/29 B42D25/324 B42D25/328 

FIELD: textile, paper.

SUBSTANCE: polymer sandwich element for paper, which has optically variable effect, is made in the form of a sandwich polymer structure containing at least one layer with microraster relief structure. It has an additional layer with printed or embossed raster of microimages, which is spatially combined with microraster relief structure. Microraster structure is made in the form of raster of spherical transparent polymer lenses or prisms or raster of Fresnel diffraction polymer structures. Printed microimages located in nodes of the printed raster consist of elements of different colours with diametre of 20-100 mcm, which are located at the distance of 40-400 mcm from each other. Mutual location of colourful elements in nodes of the printed raster is discernible in different places of a representational printed field. Inside the defined areas the mutual location of colourful elements differs from mutual location of elements outside the defined areas.

EFFECT: invention allows increasing protection degree of products with protective elements without any increase in prime cost of their production process.

3 cl, 4 dwg, 1 ex