SECURITY PAPER WITH WATERMARK (VERSIONS) AND METHOD OF ITS MANUFACTURING (VERSIONS) Russian patent published in 2013 - IPC D21H19/44 B42D15/00 

FIELD: textiles, paper.

SUBSTANCE: invention describes two versions of security paper containing a watermark of two fragments that make up a single image visible in transmitted light when folding of the security paper along the line located between two fragments of the watermark, and the imposition of the obtained areas of the paper with fragments of the watermark on one another, and the paper is manufactured based on milled cotton cellulose with the addition of wood cellulose and/or cellulose of annual plants, and/or flax cellulose, and/or polyester fibers, and/or polyamide synthetic fibers, on fourdrinier former or cylinder mould machine and comprises areas with increased transparency, located symmetrically with respect to the fold line of the overlapping fragments of the watermark. The shape and size of these fragments corresponds to overlapping fragments of the watermark, so that the boundaries of the areas with increased transparency when folding of the paper coincide completely with the boundaries of the relevant dark fragments of the watermark. Also several versions of methods of manufacturing of such paper are described.

EFFECT: increased contrast ratio and improved inside-light perception of a whole image of the watermark.

12 cl, 4 ex, 5 dwg