METHOD AND DEVICE FOR PRODUCING FRAUD-PROOF PAPER AND FRAUD-PROOF PAPER

摘要

The invention relates to fraud-proof paper and to a method and device for the production thereof. The inventive method consists in forming a first paper web provided with a protective band whose width is equal to or less than 2 mm and which is incorporated into the web during the formation thereof with the aid of a cylinder mould machine in such a way that free-access areas (windows) are formed on protruded elements of the face side of the web. Said protective band is incorporated into the first paper web during the formation thereof and after formation of the free access areas which is associated with the formation of a fibre layer representing 35-50 % of the mass of the first paper web. A second paper web devoid of the protective band is produced simultaneously with the first web and afterwards is applied to the back side thereof in such a way that when they are connected to each other the defects of the said back side are hidden. Afterwards, the thus obtained two- layer material is pressed and dried. The protruded elements are embodied in the form of waterproof elements. An additional protective element is incorporated into the first and/or the second paper web during the production thereof. For the purpose of said invention, a protective band having a width ranging from 2 to 20 mm and comprising additional protective elements is used