AN IMPROVED RETENTION/DRAINING AID COMPRISING A SILICEOUS MATERIAL AND AN ORGANIC MICROPARTICLE

摘要

According to the present invention a process is provided for making paper of paper board comprising forming a cellulosic suspension, flocculating the suspension, draining the suspension on a screen to form a sheet and then drying the sheet, characterised in that the suspension is flocculated using a flocculation system comprising a siliceous material and organic microparticl es which have an unswollen particle diameter of less than 750 nanometers.