Method for increasing filler retention of cellulosic fiber sheets

摘要

A method for increasing filler retention of cellulosic fiber sheets is disclosed, wherein cellulosic fibers with increased anionic sites are treated with either positively charged filler particles and/or amphoteric filler particles or a cationic retention aid and negatively charged filler particles and/or amphoteric filler particles. Cellulosic fiber sheets with retained filler particles are also disclosed.