Paper and paperboard production process and corresponding novel retention and drainage aids, and papers and paperboards thus obtained

摘要

The invention relates to an improved paper production process, according to which a branched polymer prepared in reverse phase emulsion is used as the main retention aid, and then bentonite is used as the secondary retention aid (a dual type system). The two additions are separated by a stage for shearing the fibrous suspension (or mass). ;A distinctly improved retention of the fines is obtained, and also a distinct improvement in drainage. Moreover, the bentonite content in the white water is reduced.