METHOD OF PRODUCING VISIBLE CONTINUOUSLY STRIPS AND/OR DELINEATED MARGINS IN PAPER, METHOD OF PRODUCING TRANSPARENT REGIONS IN PAPER, AND VALID DOCUMENT Russian patent published in 1998 - IPC

FIELD: paper making. SUBSTANCE: invention relates to producing visible, preferably transparent or semitransparent, continuous strips and/or delineated margins in paper combined with formation of paper web on paper-making machine. Method is distinguished by preventing dehydration of paper pulp or removing paper fibers from one or several sites of the surface of wire-mesh of formation mechanism of papermaking machine simultaneously with formation of paper web on it. At the same time, pulp is supplied which contains fibers differing from those of fibrous material depositing on wire-mesh and may also contain certain diluent and/or binding agent. Invention provides relatively simple and inexpensive method for using such paper to manufacture valid documents, in particular, bank notes difficult to falsify, which can be printed on usual printing-press, using usual transfer- ink for valid documents. EFFECT: enabled high falsification- protection properties with low cost. 17 cl, 6 dwg , 1 tbl