Ligninhaltige Phenol-Formaldehydharze als Bindemittel bei der Verleimung von Furnieren. Erste Mitteilung: Sulfitablauge in Kombination mit alkalischen Phenolharzen

The results show that sodium lignin sulphonates (derived from Ca-sulphite liquor) can be used as an extender or substitute for phenolic resins to produce plywood, if certain conditions, such as pressing temperature and pH-value, are adhered to. At a pressing temperature of 140°C, about 20% of the phenolic adhesive used can be substituted by sulphite liquor. The physical-technological properties of the produced three-layer boards are fully equivalent to those of plywood, using phenolic resin alone as an adhesive. At a pressing temperature of 190°C, about 30% of the phenolic resin used can be substituted without impairing the physical-technological properties of the boards significantly