METHOD FOR PRODUCING PAPER, PAPERBOARD AND CARDBOARD

摘要

The invention relates to a method for producing paper, paperboard and cardboard by draining the pulp on a sieve, in the presence of at least one cationic polymer. Before sheets are formed, a mixture of at least one essentially linear, cationic polyelectrolyte and an optical brightening agent is added to the pulp, said mixture containing at least two parts by weight of the polyelectrolyte per part by weight of the optical brightening agent.