Effects of Beating Degree on the Properties of Foam-formed SwBKP Sheets

Abstract

In order to increase the strength properties of foam-formed sheets, the effects of the beating degree of SwBKP (softwood bleached kraft pulp) on the drainage rate on wire and the properties of the foam-formed sheets were evaluated. It was found that the strength properties of foam-formed sheets can be improved without reducing the bulk by increasing the beating degree of a chemical pulp. Foam-formed sheets showed a superior formation than water-formed sheets at a lower beating degree while the formation of foam-formed sheets deteriorated with increasing beating degrees. The beating of SwBKP decreased the drainage rate in both form-forming and water-forming methods. Under conditions of high vacuum pressure, the foam-forming improved the drainage on the wire section. Under conditions of low vacuum pressure, the drainage rate of foam-forming was initially slower compared to that of the water-forming while it was reversed after a certain period of time. In addition, the beating degree of SwBKP did not influence the foamability and the stability of fiber foam.