METHOD FOR THE PRODUCTION OF PAPER AND CARDBOARD, CORRESPONDING NOVEL RETENTION AND DRAINING AGENTS, AND PAPER AND CARDBOARD THUS OBTAINED

摘要

A process for the manufacture of paper, board or similar products, comprises first of all, adding, to the paper pulp fibrous suspension, at least one main retention aid composed of a cationic (co)polymer. Then optionally the flocs obtained are sheared. Subsequently there is added to the suspension, separately or as a mixture, in any order: at least one secondary retention aid chosen from the group consisting of silica derivatives and anionic or amphoteric organic polymers, and at least one tertiary retention aid composed of a crosslinked anionic organic polymer with a size of greater than or equal to 1 micrometer and exhibiting an intrinsic viscosity of less than 3 dl/g.