A strength additive system for manufacturing paper, board, tissue or the like includes preferably as separate components, a cationic strength agent, such as a cationic polymer with aldehyde functional groups, and an anionic copolymer obtained by polymerization of a reaction mixture including (meth)acrylamide and anionic monomers, the standard viscosity of the obtained copolymer being in a range of 1.5-5.0 mPas. A method for manufacturing of a paper, board, tissue or the like is further disclosed.

A cationic glyoxylated polyacrylamide polymer composition having improved storage stability for use in manufacture of paper, board or the like, which aqueous composition includes a glyoxylated polyacrylamide polymer having a cationic charge density in a range of 0.8-1.8 meq/g of dry polymer in dry content of 5-15% and a buffering acid. The aqueous composition has pH in a range of 2.2-4.0 and a viscosity of less than 80 mPas measured at 25 C. by using a Brookfield viscometer after 30 days storage at 35 C. or after 60 days storage at 23 C.

A method is disclosed for increasing strength properties, preferably burst strength and SCT strength, of a paper or board product. The paper or board product is manufactured from a fibrous web produced by a multilayer headbox, where an aqueous layer is formed between at least a first and a second fibre layer formed from fibrous stock suspension(s), and where feed water for the aqueous layer includes at least one cationic polymer. The method of the invention includes adding an anionic additive selected from a group comprising anionic synthetic organic polymers, anionic polysaccharides, and any of their combinations to the feed water before formation of the aqueous layer.

The invention relates to a lightweight linerboard for corrugated board with good strength properties and which reduces problems with washboarding in the thereof produced corrugated board. The linerboard of the invention comprises at least one ply comprising 20-80 wt % CTMP from wood fibers and 20-80 wt % chemical pulp, all percentages calculated on the total fiber weight of said first ply, wherein the CTMP exhibits a bulk of at least 2.5 cm.sup.3/g.

The invention relates to a lightweight linerboard for corrugated board with good strength properties and which reduces problems with washboarding in the thereof produced corrugated board. The linerboard of the invention comprises at least one ply comprising 20-80 wt % CTMP from wood fibers and 20-80 wt % chemical pulp, all percentages calculated on the total fiber weight of said first ply, wherein the CTMP exhibits a bulk of at least 2.5 cm.sup.3/g.

The present disclosure provides cellulose reactive glyoxalated vinylamide polymers which impart improved wet strength decay properties, as well as high efficiency of wet strength build in paper products. A method of preparing a cellulose reactive glyoxalated vinylamide polymer composition, and methods of its use in maunfacturing paper products, as well as the resulting paper products, are also provided.

The invention relates to powdery, water-soluble, cationic polymer composition comprising at least two different cationic polymers, namely a first cationic polymer and a second cationic polymer, which differ in chemical nature and molecular weight, as well to a method for producing such powdery, water-soluble, cationic polymer composition, and to its use for promoting flocculation in solid-liquid separation, for example as a retention aid in paper manufacture, and in sludge dewatering/wastewater purification.

The invention relates to powdery, water-soluble, cationic polymer composition comprising at least two different cationic polymers, namely a first cationic polymer and a second cationic polymer, which differ in chemical nature and molecular weight, as well to a method for producing such powdery, water-soluble, cationic polymer composition, and to its use for promoting flocculation in solid-liquid separation, for example as a retention aid in paper manufacture, and in sludge dewatering/wastewater purification.

A polymer composition includes a first host polymer, which is a copolymer of (meth)acrylamide and at least one cationic first monomer, and a second polymer, which is a copolymer of (meth)acrylamide and at least one cationic second monomer. The second polymer is polymerised in presence of the first host polymer, and the first host polymer has a higher cationicity than the second polymer, the difference in cationicity of the first host polymer and the second polymer being at least 3 mol-%, at least 5 mol-%, more preferably at least 7 mol-%. The polymer composition has a standard viscosity of >2.0 mPas, measured at 0.1 weight-% solids content in an aqueous NaCl solution (1 M), at 25 C., using Brookfield VII T viscometer with UL adapter. The invention relates also to uses of said polymer composition.

The invention relates to a transfer material for dye sublimation processes, comprising a base paper, which is coated on one side with a color-receiving layer, wherein the base paper contains at least 1.5% by weight, based on the mass of the pulp, of a polymer dispersion selected from the group consisting of polyacrylates, polyesters, polyolefins or mixtures thereof. The invention further relates to a process for producing a transfer material according to the invention, comprising the steps of: (a) producing a base paper on a paper machine, wherein at least 1.5% by weight, based on the mass of the pulp, of a polymer dispersion selected from the group consisting of polyacrylates, polyesters, polyolefins or mixtures thereof are added to the pulp suspension during production of the base paper; (b) drying and smoothing the base paper; (c) applying the color-receiving layer to a surface of the base paper; and (d) drying the transfer material obtained in step (c). The invention further relates to a process for transferring an image onto a receiving material by sublimation, wherein a transfer material according to the invention is printed with an image by way of the inkjet printing process, and the image is transferred onto a receiving material by sublimation.