Paper, cardboard or paperboard-like material and a process for its production

摘要

Paper, cardboard or paperboard-like material containing inorganic fibres, inorganic particle-like additives and organic binders and flocculating agents characterized in that (1) the particle-like inorganic additives constitute 40-80% by weight of the dry matter of the material; (2) the inorganic particle-like additives are composed of (2.1) a base filler of which at least 20% by weight has a particle size of <2 (my)m and not more than 20% by weight has a particle size of >20 (my)m on the one hand and <0.5 (my)m on the other hand, and (2.2) an anionic flocculating active pigment of which at least 50% by weight has a primary particle size of <2 (my)m, (3.1) the organic flocculating agent is a cationic polymeric carbohydrate with an average molecular weight of 100,000 to 2,000,000 and a degree of substitution of 0.01 to 0.3 and is present in a quantity of 0.5 to 6% by weight, based on the dry matter of the material, and (3.2) 1000 g of base filler is unable to bind more than 0.1 mMol and 1000 g of anionic flocculating active pigment is able to bind at least 0.1 mMol cationic carbohydrate under flocculation.