Abstract: The present invention relates to a process for improved dewatering and retention in the production of paper, where an anionic retention agent based on starches, cellulose derivatives or guar gums having no cationic groups and an acidic solution of an aluminum compound are added to the stock containing lignocellulose-containing fibres and optionally fillers. The pH of the stock prior to the addition of the aluminium compound should be at least about 6 to obtain the desired cationic aluminium hydroxide complexes in the stock. The present invention is cost effective and insensitive to the content of calcium in the white water.

Abstract: A process for improved dewatering and retention in the manufacture of paper, where a retention agent containing anionic groups and being based on a polysaccharide or being an acrylamide-based polymer and an alkaline solution of an aluminate are added to the stock containing lignocellulose-containing fibres and optionally fillers. The pH of the stock prior to the addition of the aluminate should be below about 7 to obtain the desired cationic aluminum hydroxide complexes in the stock. The present process is cost effective and insensitive to the content of calcium in the white water.

Abstract: The present invention relates to a sized paper containing a hydrophobic zeolite. Suitably, the sized paper is fine paper, kraft liner or paperboard. In paperboard intended for solid or liquid foodstuffs, tobacco or medicines, use is also made of the capacity of the zeolite to reduce, by adsorption, the problem of transfer from the package to its content of substances causing undesirable taste or hazardous substances. The present invention also relates to a method for production of the sized paper by forming and dewatering a suspension of lignocellulose-containing fibres, where the dewatering is carried out in the presence of a hydrophobic zeolite. Due to the inert nature of the zeolite, it can be used in papermaking within a very broad pH range. The present invention also relates to the use of a hydrophobic zeolite for the production of sized paper as well as use of the thus-sized paper in packaging material.

Abstract: Aqueous dispersions of rosin and synthetic sizing agent wherein the particles in the dispersed phase contain a mixture of rosin and the synthetic sizing agent and wherein the dispersions contain a polyaluminum compound. The dispersions are prepared by homogenization of a homogenous mixture of rosin material and the synthetic sizing agent and the polyaluminum compound can either be present at the production or be added to an aqueous dispersion of mixed particles. The dispersions are used as sizing agents at the production of paper, paper board, board and similar products.