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

摘要

The invention relates to an improved paper production process according to which a cross-linked polymer prepared in reverse-phase emulsion and sheared before introduction into the fibrous mass 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 not separated by any mandatory stage for intense shearing of the fibrous suspension (or mass). The paper manufacturer can therefore be free from the constraints of shearing the pulp. A distinctly improved retention of the fines is obtained, and also a distinct improvement in drainage. In addition, the bentonite content in the white water is reduced. Lastly, excellent formation is maintained.