| 摘要 |
A process of making paper or paperboard with improved ash retention relative to total retention comprising the steps of providing a thick stock cellulosic suspension that contains filler, diluting the thick stock suspension to form a thin stock suspension, in which the filler is present in the thin stock suspension in an amount of at least 10% by weight based on dry weight of thin stock suspension, flocculating the thick stock suspension and/or the thin stock using a polymeric retention/drainage system, draining the thin stock suspension on a screen to form a sheet and then drying the sheet, in which the polymeric retention/drainage system comprises, i) a water-soluble branched anionic polymer and ii) a water-soluble cationic or amphoteric polymer, wherein the anionic polymer is present in the thick stock or thin stock suspension prior to the addition of the cationic or amphoteric polymer. The process brings about improved ash retention relative to total retention. |
