METHOD FOR MANUFACTURE OF FIBROUS BASE INCLUDING ELONGATED MEMBER WITH VARIABLE EDGE PROFILE Russian patent published in 2007 - IPC D21H21/42 D21F11/00 B42D15/00 B44F1/12 

FIELD: production of paper for banknotes, valuable documents etc.

SUBSTANCE: method involves steps of introducing elongated flexible impermeable member into contact with window forming means provided on movable supporting surface; placing filaments onto supporting surface for formation of fibrous base. Filaments are deposited so that upon placing of filaments onto supporting surface, elongated member is introduced into base to thereby form first set of windows on one surface of substrate the moment said member comes into contact with window forming means. Elongated member is partly opened within said windows. Elongated member has a plurality of wide regions divided by narrow portion, with width of wide regions preventing deposition of filaments in these wide regions and formation of second set of windows on opposite surface of base, wherein elongated member is also at least partly open. Narrow portions are such that they allow filaments deposited thereon to cover narrow portions of opposite surface of fibrous base at a distance from supporting surface. Described in Specification are base manufactured by said method, protected member manufactured from said base, and paper including elongated impermeable member open at both sides of base in variable or coinciding manner to prevent said paper from counterfeit.

EFFECT: improved quality of paper base and enhanced reliability in protecting from counterfeit.

19 cl, 7 dwg