1. Fibre Technology, Royal Institute of Technology, Teknikringen 56, 100 44 Stockholm, Sweden
2. BIM Kemi AB, Box 3102, SE-443 03 Stenkullen, Sweden
3. Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
4. Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokko, Nada, Kobe 657-8501, Japan