Abstract:
A method for controlling the liquid level in the premixing unit (500) of a Hatschek machine (1000) comprising a sheet manufacturing machine (100), a cement slurry preparation mixer (200), a settling tank (300), a selectifier (400), and a premixing unit (500), wherein a level meter measures the liquid level in the premixing unit and generates a measurement signal, and wherein said measurement signal directly or indirectly controls a control valve (801), such that the amount of the portion of the water-loaded cement slurry of the sheet manufacturing machine (100) that is supplied to the selectifier (400), is controlled.
Abstract:
An apparatus for manufacturing security paper, comprising at least one main forming roller (2), which is provided with a lower portion or forming portion (3), which is arranged inside a forming box (4) that contains the paper paste, an upper portion or deposition portion (5), which is arranged below a collecting wire (6) that can move along an advancement direction and is designed to receive, at a collecting face (6a) the sheet (7) formed on the forming roller (2), and a device (8) for depositing security elements (201) that is arranged upstream of the main forming roller (2) along the advancement direction (100) of the collecting wire (6) and is adapted to deposit the security elements (201) at the collecting face (6a).
Abstract:
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
Abstract:
A cylinder former (10) having a variable hydraulic pulse whilst drainage, for use in papermaking comprising a drainage means comprising a cylinder mould (12) and a contoured member (34) adjacent the cylinder mould having a plurality of hills and valleys which force entrained liquid through the fiber suspension forming on the cylinder mould so as to improve sheet formation. A baffle (39) is provided in the discharge portion of the former to prevent stock build-up therein.
Abstract:
Die Erfindung betrifft eine Papiermaschine zur Herstellung von Papier oder papierähnlichen Stoffbahnen, wobei die Vorrichtung einen maschinenbreiten Faserstoffsuspensionszulauf (4), einen Trog (1) mit darin rotierendem Gleichstrom- Rundsieb (2), einen Trogzulauf (8) und eine Vliesabnahmevorrichtung (14) aufweist, wobei der Trogzulauf (8) eine Strömungsleitvorrichtung (20) aufweist, wobei die Strömungsleitvorrichtung (20) eine den Suspensionsspiegel (A1) der Faserstoffsuspension abdeckende und den Suspensionsstrom kontinuierlich beschleunigende in den Trogkanaleinlauf (9) lenkende Abdeckung (19) aufweist.
Abstract:
Papier de sécurité comportant un substrat fibreux et au moins un fil de sécurité (7) intégré en fenêtres dans ce substrat fibreux, le substrat fibreux présentant au moins une région d'opacité variable (16) s'étendant au moins partiellement sur un pont (13) du substrat fibreux situé entre deux fenêtres (10), de préférence successives, le long du fil de sécurité.
Abstract:
According to the first variant of the invention, the inventive method consists in using a thread in the form of a thread which is made of an elastic shaped plastic material provided with protective elements, bringing said thread into contact with the slot of a grid cylinder prior to the contact of the grid with a paper pulp, placing the thread core on the slot bottoms for fixing said thread core to the surface of paper, raising wings upward by means of inclined slots and in fixing said wings in the paper thickness during shaping and pressing. According to the second variant, the thread contact with the slot is carried out after the contact of the grid with the paper pulp, the thread core being disposed on the layer of the slot bottom and inside the paper. The wings are raised upward by means of the inclined walls of the slot and fixed to the paper surface by dehydration during shaping and pressing. In the third and fourth variants, the thread is embodied in the form of an endless strip which is made of a metallised plastic material and provided with a central core carrying visually controlled or machine-readable protective information and with side elements in the form of wings which are disposed symmetrically and/or asymmetrically with respect to the longitudinal axis of said core and arranged in an ordered and/or disordered periodical manner.
Abstract:
A method for manufacturing watermarked paper (11), comprising: - a step of forming a first fibrous panel (1) which comprises at least one watermark element; - a step of forming a second, thin fibrous panel (2); - a step of removal, by way of suction, of at least one portion of the second, thin fibrous panel (2) in order to produce a localized reduction in thickness at a first face (2a) of the second, thin fibrous panel (2), so as to provide at least one accommodation seat (2b) intended to accommodate a security element; - a step of coupling between the first fibrous panel (1) and the face of the second, thin fibrous panel (2) which lies opposite the first face (2a).
Abstract:
The invention relates to improvements in methods of making security features, in particular electrotype security features. The electrotype for forming an image during a paper making process comprises a mesh to which is attached at least one image forming element.