Abstract:
The present invention relates to a method for the production of filler-containing paper, cardboard and paperboard, comprising the dewatering of a paper pulp with sheet formation and drying by adding biodegradable polyester fibers and/or polyalkylene carbonate fibers to the paper pulp.
Abstract:
A process for preparation of paper, pasteboard, or cardboard involving cutting of the paper pulp, addition of microparticles of cationic polymer, and a finely divided inorganic component after the last cutting step and before pulp swelling, dewatering of the pulp, and sheet formation and drying of the sheets is new. A process for preparation of paper, pasteboard, or cardboard involving cutting of the paper pulp, addition of microparticles of cationic polymer, and a finely divided inorganic component after the last cutting step and before pulp swelling, dewatering of the pulp, and sheet formation and drying of the sheets. The cationic polymer of the microparticle system is cationic polyacrylamide, polymer containing vinylamine units, and/or polydiallyl dimethylammonium chloride containing polymer of mean mol.wt. 500,000 Dalton, and maximum charge density 4.0 meq/g, where the microparticle system free from polymers of charging density (sic) more than 4 meq/g is used as the retention agent.
Abstract:
A process for the production of paper, board and cardboard by draining a paper stock containing interfering substances in the presence of polymers which contain vinylamine units and which have an average molar mass Mw of at least 1 million, a high-consistency stock first being prepared, at least one polymer containing vinylamine units and having an average molar mass Mw of at least 1 million and a degree of hydrolysis of from 1 to 20 mol % being metered into the high-consistency stock, the high-consistency stock being diluted to a low-consistency stock by adding water, and the low-consistency stock being drained, the polymers being hydrolyzed homo- or copolymers of N-vinylcarboxamides additives for reducing deposits in the wire part, press section and drying section of paper machines.
Abstract:
Method for producing paper, paperboard and cardboard having a high dry strength by adding at least one water-soluble (a) polymer comprising vinyl amine units and at least one (b) polymer comprising ethylene imine units and at least one water-soluble polymeric anionic compound to form a paper material, dewatering the paper material during the formation of sheets, and drying the paper product, wherein the water-soluble cationic polymers (a) and (b) are metered in an arbitrary sequence or as a mixture to form a paper material, and paper products obtained according to the method.
Abstract:
A barrier packaging material containing a composite which comprises i) a cellulosic layer; ii) at least one metal layer which will dissolve under alkaline conditions; and iii) at least one polymer layer, in which the polymer is hydrolysable under alkaline conditions. The invention also relates to articles comprising the barrier packaging material. Further, the invention concerns the use of a polymer, which is hydrolysable under alkaline conditions, as a protective layer in barrier packaging products. In addition the present application is also concerned with a method for recycling the aforementioned barrier packaging products. Specifically the barrier packaging products are initially taken in an aqueous wastepaper suspension which is either pulped in an alkaline medium and/or treated in an alkaline medium in a deinking process and in which the metal and polymer are then separated from the cellulosic fibres contained in the cellulosic layer.
Abstract:
The invention relates to a method for recycling paper products glued and/or coated with polymers, wherein the paper products glued and/or coated with polymers are placed in an aqueous wastepaper suspension, said wastepaper suspension a) is broken down in the presence of at least one hydrolase, b) is broken down in an alkaline medium, and/or c) is treated in a de-inking process in an alkaline medium, and the polymers are subsequently separated from the wastepaper suspension, wherein the polymers are biodegradable polymers.
Abstract:
Method for producing paper, paperboard and cardboard having a high dry strength by adding at least one water-soluble (a) polymer comprising vinyl amine units and at least one (b) polymer comprising ethylene imine units and at least one water-soluble polymeric anionic compound to form a paper material, dewatering the paper material during the formation of sheets, and drying the paper product, wherein the water-soluble cationic polymers (a) and (b) are metered in an arbitrary sequence or as a mixture to form a paper material, and paper products obtained according to the method.