Laboratory scale investigation of foam forming

Much is known already about the properties of pure foams. On the other hand, very little is known about the chemical interactions in between foaming agents and papermaking raw materials in foam-fibre systems. VTT and YKI (Institute for Surface Chemistry, Sweden) have focused in this topic in close co-operation. Foams made with different combinations of surfactants, fibres and paper making additives have been studied using laboratory scale facilities. Screening studies allowed to identify three surfactant candidates that allow for the rapid production of fibre-foams with the target air content and bubble size distributions. Further studies to better understand the underlying reasons for their good performance are on their way while at the same time these systems have recently been used to prepare A4-size sheets in a foam hand sheet mold which will be used to evaluate the effect of the surfactants on the properties of the sheets.