An evaluation of three formation testers using radiata pine and spruce kraft pulps

Uniformity of sheet structure is important for the processing and performan ce of paper and paperboard. The measurement of mass distribution or formati on is a fundamental way of assessing product uniformity, Three formation te sters, namely, Toyo Seiki, PFI and Ambertec Beta, were used for comparison of handsheets from radiata pine and spruce bleached kraft pulps. A secondar y aim was to study the Variation of formation in handsheets made from a ben chmarked single-fibre resource while decoupling the processing effects in i ndustrial paper machine formers. Trends in the formation data with changing fibre class are similar although the results vary from instrument to instrument. The formation index values from all formation testers correlated well with selected fibre properties. Preliminary data are presented for some kraft-TMP composite handsheets.