Starch Xanthide in Pilot Paper Machine Trials

Starch xanthate, an inexpensive water-soluble derivative of starch, was oxidatively converted to the insoluble xanthide and evaluated on a pilot paper machine as a wet- and dry-strength additive for unbleached kraft paper. Pilot data are compared with data reported previously that were obtained in laboratory evaluations. Differences observed in xanthide effectiveness on scale-up from laboratory to pilot evaluations are described, and the variables responsible identified.