Abstract: Method for the production of mechanical or chemi-mechanical pulp as raw material for paper or cardboard. According to this method, the pulp is fibrillated and the fibrillated pulp is bleached in alkaline conditions. According to the present invention, the pulp is screened to separate the reject from the accept, at maximum approximately 60% of the total amount of pulp is separated as the reject, the reject is bleached separate from the accept, and, after that, the bleached reject is remixed with the accept. When operating according to the present invention, the strength of the pulp increases and the energy used for refining is reduced, which is seen both in the refining of the reject and in the post-refining of the final mechanical pulp.

Abstract: The invention relates to cardboard used in authenticity products, comprising a fiber matrix having two surfaces, whereby the second surface of the fiber layer has a layer of surface sizing containing a marking agent in a particle form, its particle size being smaller than 50 ?m. By incorporating the marking agent into the surface sizing, the particles of the marking agent can be attached to the board, at the same time decreasing their total consumption by 80 to 90% compared with a case where they would be added to pulp. By using particles of a size less than 50 ?m, a top free from streaks and roughness can be formed, which streaks might otherwise weaken the quality of the product.

Abstract: The use of filler for the manufacture of paper and board products the air permeability of which does not substantially change as a function of the amount of filler, the filler being at least in part made up of cellulose or lignocellulose fibrils on which there have been deposited light-scattering material particles the proportion of which is 67-85%, preferably approx. 70-82%, of the weight of the filler.

Abstract: A process for producing a coated paper, comprising the steps of: a) providing a base paper, the fraction of long-fiber chemical pulp in the base paper being at least 25% by weight, the base paper leaving an absolute moisture content of ISO 287 of not less than 2.5%, the base paper having a water absorbency to ISO 535 for a test time of 10 s (Cobb10) of 5 to 20g/m2, and the base paper having a (Fenchel) wet elongation, measured parallel to the machine direction, of not greater than 0% and, measured transverse to the machine direction, of not greater than 3%, b) applying 10 to 40g/m2 (ovendry) of an aqueous coating composition to at least one face of the base paper, to give a coated base paper, and c) conditioning the coated paper obtained in step b).

Abstract: A device for mechanical defibration of wood comprises a defibration surface for processing of wood raw material and loosening of fibers, said defibration surface comprising grinding grits fastened on a metal base surface. The grits (1) fastened on the metal base surface (2) are positioned within a determined distance from each other on the base surface, so that they form a regular defibration surface.

Abstract: A method of manufacturing a multilayer fibrous product. The product comprises at least two overlapping layers, each of which has a different fiber composition, and in the production of the product, chemical short stock is used at least partly. In the method, short stock is brought to a screening stage where fines, which pass a screen having an average hole size of 0.2-1.5 mm, are separated from it, in order to prepare at least two fiber fractions having different fiber compositions, and the fractions generated are recovered and included in different layers of the same fibrous product. With the invention, it is possible to screen an initial material and form a product which has better properties than a corresponding product, the initial material pulp of which has only been refined.

Abstract: The invention relates to a method for producing a visually identifiable diffractive pattern on a substrate by subjecting the substrate to pressure by bringing it into contact with a surface of an embossing plate. An imprinted paper or paperboard sheet, which is varnished at the contacting area of the embossing plate and the substrate is used as a substrate for the embossing. The invention relates also to a product manufactured using the described method. The method is applicable, for example, for common packaging materials, which contain a paperboard, imprinting and a varnish layer for producing a visually attractive and unique marking.

Abstract: Disclosed herein in a preferred embodiment is a recording material comprising a substrate and a coating comprising at least 3 plies, wherein the outermost ply contains nanoparticles and the inner plies together contain at least one color former, at least one color developer, at least one absorber and at least one solubilizer, and no ply contains both a color former and a color developer. Also disclosed is a process for producing the recording material of the invention and also to a laser marking process wherein the recording material is irradiated with a laser.

Abstract: The present invention provides a novel method and apparatus for producing pulp from lignocellulosic raw material, such as wood or annual or perennial plants, by mechanical defibration. According to the invention, fibers are peeled from the wood by means of grinding grits arranged on a defibration surface, wherein at least 90% of the protrusion difference distribution between adjacent or neighboring grits on the surface belongs to a value region maximally as wide as the average grit diameter. By means of the invention, a reduction in specific energy consumption of up to 50% or even more can be obtained.

Abstract: The present invention relates to an inkjet recording material comprising: a) a substrate b) at least one ink-accepting layer applied to at least one side of the substrate, containing at least one pigment selected from the group consisting of calcium carbonate, calcined clay, satin white or mixtures thereof, the mean particle size of the pigment being from 0.1 ?m to 1.5 ?m, c) at least one surface layer applied to the at least one ink-accepting layer, the surface layer containing cationic inorganic particles, the inkjet recording material having a gloss in the range from 10 to 60, measured according to DIN 54502 R? (45°) (measuring angle 45°), on the side to which the at least one surface layer was applied, and the density of the inkjet recording material being greater than or equal to 0.95 g/cm3, and to a process for its production.

Abstract: The present invention relates to a method for applying interference pigments to a substrate, comprising the steps: a) provision of a substrate and b) application of a preparation to at least one side of the substrate, where the preparation contains at least one surfactant and at least one interference pigment, the interference pigment having a carrier material and at least one coat applied to the carrier material, and a substrate obtainable by the abovementioned method.

Abstract: A process for producing a coated paper, comprising the steps of: a) providing a base paper, the fraction of long-fibre chemical pulp in the base paper being at least 25% by weight, the base paper leaving an absolute moisture content of ISO 287 of not less than 2.5%, the base paper having a water absorbency to ISO 535 for a test time of 10 s (Cobb10) of 5 to 20 g/m2, and the base paper having a (Fenchel) wet elongation, measured parallel to the machine direction, of not greater than 0% and, measured transverse to the machine direction, of not greater than 3%, b) applying 10 to 40 g/m2 (ovendry) of an aqueous coating composition to at least one face of the base paper, to give a coated base paper, and c) conditioning the coated paper obtained in step b).

Abstract: The present invention relates to a process for the production of nonuniformly intensely colored paper with improved printing or lettering features, and paper produced by this process.

Abstract: The invention relates to a method for coating cellulose particles with a light scattering material, to coated cellulose particles, to the use thereof as a filler and as a coating pigment in paper and board, and further, to methods for producing and for coating paper and board.

Abstract: A method of manufacturing a fibrous web comprising a filler. According to the method, the filler is fed into the fibre slush and a fibrous web is formed of the filler-bearing fibre slush, and this web is dried at the paper or cardboard machine. The filler used is a composite material which comprises cellulose or lignocellulose fibrils, onto which light-scattering material particles have been precipitated. According to the present invention, the filler is brought into contact with the dispersant before it is mixed into the fibre slush. With this solution it is possible to significantly improve the light-scattering properties of papers and cardboards, without decreasing the retention of the filler.

Abstract: The invention relates to a marking electromagnetically readable from a substrate, a method for producing such a marking, and a memory medium. The marking comprises first areas on a substrate at a distance to each, which comprise at least one electrically conductive material and the electrical conductivity of which is greater than a defined threshold value, and second areas arranged between the first areas, the electrical conductivity of which second areas is less than or equal to the said threshold value. According to the invention, at least two first areas differ substantially from each other in electrical conductivity. With the aid of the invention it is possible to create a marking, the amount of information contained in which is many times that contained in previous electrical markings.

Abstract: Method for the production of mechanical or chemi-mechanical pulp as raw material for paper or cardboard. According to this method, the pulp is fibrillated and the fibrillated pulp is bleached in alkaline conditions. According to the present invention, the pulp is screened to separate the reject from the accept, at maximum approximately 60% of the total amount of pulp is separated as the reject, the reject is bleached separate from the accept, and, after that, the bleached reject is remixed with the accept. When operating according to the present invention, the strength of the pulp increases and the energy used for refining is reduced, which is seen both in the refining of the reject and in the post-refining of the final mechanical pulp.

Abstract: The invention relates to a method for manufacturing a web comprising wood-based fibres and man-made fibres. A polymer is added to a fibre suspension comprising wood-based fibres and man-made fibres to improve the web formation and to slow down the removal of water in the wire section of the paper machine.

Abstract: The present invention concerns a method of producing a calendered, coated fibrous web, according to which method a fibrous web is coated with a coating colour containing a coating pigment, and the coated fibrous web is calendered. According to the invention, at least 1%, preferably 10 to 100% of the weight of the pigment comprises calcium oxalate, and calendering the coated web by online calendering. The properties of the calcium oxalate pigment are so advantageous for calendering that it is possible to obtain a reasonably high gloss already with a machine calender (online calendering), which will eliminate need for a separate offline calender in the production line of matt surface papers.

Abstract: The purpose of this invention is to provide a method and an apparatus for producing thermomechanical fibers using less energy per ton that has previously been required for similar type of production. The invention is based in that at least two refiners are combined so that mixture of chips, water and steam is first fed into a first refiner wherein the chips are broken up and the mass flow from the first refiner is then fed into the second refiner for breaking the fibers to final freeness level. The mass flow of steam and fibers is fed forwards at least in the first refiner by the rotational energy of the refiner rotor so that essentially no flowback of the steam occurs. The mass flow exciting the first refiner is fed completely to the second refiner and no steam is extracted from the mass flow before the second refiner.