In mechanical pulping, naturally connected wood fibres are separated and developed into suitable papermaking pulps by mechanical action. Both the optimization of the energy-intensive refining process and the relevant characterization of the highly heterogeneous mechanical pulp constituents have been ongoing challenges for many decades. Advanced fibre characterization tools have proven very valuable for understanding how the different types of wood fibres are separated and further developed in existing refining processes. Their application has thus paved the way for further process optimization and the development of novel process concepts in mechanical pulping.

For the fibres in mechanical pulps, dimensions, shape, cross-sectional geometry and the structure of the fibre wall and fibre surface have been proposed as the fundamental properties. They again determine the strength, conformability and bonding potential of the fibre. At PFI our ambition is to characterize these fibre properties at a level of detail that allows us to accurately quantify important refining effects such as axial fibre splitting, flexibilization, fibre wall delamination, fibre wall reduction, external fibrillation or disintegration of fibre bundles into individual fibres. Advanced mechanical pulp fibre characterization and field expertise has also been the foundation for our research, targeting e.g. multi-layered sheet structures or synergistic effects between mechanical pulps, nanofibrils and fillers. 

These and other measurements have been successfully applied in numerous research projects as well as customer orders over the last decade, and we gratefully acknowledge the financial contribution by and fruitful co-operation with partners and customers such as Norske Skog AS, Andritz AG, Stora Enso AB, Holmen Paper AB, Södra Cell AB, SCA, EKA Chemicals AB, Metso AB, the Research Council of Norway and NTNU.