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Method of papermaking with protecting element, protecting element and method of its production Method of papermaking and the method of production of the protecting element are proposed. The protrusions or recesses in the form of a light watermark are formed on a paper, and these protrusions or recesses are sealed. On some parts of the paper surface, containing the recesses, a paint layer with a negative image is applied. The paint layer covers no more than 80% of the recesses surface. The protecting element is a composite image consisting of protrusions or recesses formed on the paper in the form of a light watermark, and a paint layer with a negative image applied on these protrusions or recesses, covering not more than 80% of the recesses surface. |
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Method of papermaking with multi-tone watermark lies in the use for casting and moulding of the paper web on a papermaking machine of the relief mask representing a partially water-permeable moulding element. The element is formed on the surface of the cylinder forming fabric, or on the dandy roll of the fourdrinier former. The mask has a variable height of the image area of the watermark, created by the relief stamping of the fabric, with electrotype and/or conjoint stamping of the fabric and electrotype and/or use of several layers of the electrotype. Individual, successive layers of electrotype in the mask can have openings which are different in the diameter and the density of location. The mask is assembled out of several layers of perforated plates of metal or plastic plates or composite materials. The paper and printing product made by the above method is claimed, which are protected against forgery. |
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Sheet containing water mark or sign pseudo-water mark visible only on one side of sheet Sheet comprises a surface of the front side and the surface of the back side and at least one water mark or pseudo-water mark. And at least a part of the said water mark or pseudo-water mark is visible in transmitted light only on one side of the said sheet. |
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Counterfeit-proof paper including water signs with multitone effect, and mesh to produce this paper Invention relates to pulp and paper industry, in particular to production of paper, with water sign, to make banknotes and secure documents that require higher counterfeit protection. Counterfeit-proof paper includes water signs with multitone effect, having light and dark elements, visually perceived in passing light in the form of raster image, besides, light elements are characterised by smaller weight per unit of paper area, compared to dark elements. At the same time total area of light elements of water sign, optical density of which is less than optical density of paper, makes at least 1% of total area of paper, and depth of light elements of water sign does not exceed 70% of paper thickness. Mesh to manufacture counterfeit-proof paper comprises masks to form water sign, which are solid elements arranged between perforated sections of mesh, besides, at least on one mask there are microholes with diametre of not more than 0.25 mm, and total area of microholes makes not more than 15% of overall area of mask. |
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Security marks with bragg diffraction Method of marking articles illuminated with a water mark comprises steps on which an ordered regular array of particles is deposited on the article in a configuration which marks the article, where radiation with detected wavelength is diffracted on the said array. An article with a water mark made using the said method is also proposed. The method of making an article which shows an image comprises steps on which an ordered regular array of particles is deposited in an image configuration, the said particle array is covered by a matrix composition and the coating of the particle array is fixed such that the image is visible when radiation is diffracted on the said array. |
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Counterfeit-proof paper, method and apparatus for manufacturing the same Counterfeit-proof paper has through opening made during papermaking process and free from definitely delimited edge on its edge portion. Paper may consist of two layers, first layer being provided with window formed during papermaking process. Paper comprises through opening having sizes less than window sizes. Method for manufacturing cloth of papermaking machine involves furnishing cloth with flexible or movable continuity disturbing member which prevents accumulation of pulp on cloth portion occupied by said member; forming paper web furnished with through opening; withdrawing paper web from cloth so that continuity disturbing member is deformed or sunk under cloth. |
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Grid has filigree members fixed on grid and designed for local reducing of paper water loss for producing of filigree watermark on paper. Filigree members are made in the form of various figures, patterns, or text produced by shaped cutting from sheet material. There are through apertures and/or slots provided in body of filigree member, said apertures having cross size below 500 micron and being designed for creating zones with higher water loss. Method involves forming paper web on grid of round grid-type papermaking machine; dehydrating during pressing of paper web; forming paper on grid in order to produce filigree watermark having additional picture provided on the background of filigree watermark and having higher optical density as compared to optical density of filigree watermark. |
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Paper containing watermarks and/or embossed members Paper sheet has at least three corners and three sides connected in said corners, wherein angular strengthening watermarks are formed in each of said corners. Alternatively or in addition to it, angular strengthening embossing members are formed in each of said corners. Also, according to another version, paper sheet has at least three corners and three sides connected in said corners, wherein edge strengthening watermarks are formed in the vicinity of mid portion of each of said edges or said watermarks cover mid portion of each of said edges. |
Another patent 2551183.