Abstract: The invention relates to a method for producing starch solutions of high cation equivalent value (with a DS of 0.1-1.0). The starch to be cationized, advantageously an oxidized starch, is slurried to form a suspension of about 10-80% solids content in an aqueous mixture of a cationizing agent. In the cationization 2,3-epoxypropyltrimethylammonium chloride or an equivalent chlorohydrin-functional cationizing agent is used by about 90-1100 g per kg starch solids, and a catalyst is added to the slurry. The reaction is carried out at a high solids content of 40-80%, preferably 50-60%, in at least two successive steps, in the first of which a temperature of about 5-40° C. is maintained, and in the second step a temperature of about 70-180° C.

Abstract: The invention relates to a method for producing starch solutions of high cation equivalent value (with a DS of 0.1-1.0). The starch to be cationized, advantageously an oxidized starch, is slurried to form a suspension of about 10-80% solids content in an aqueous mixture of a cationizing agent. In the cationization 2,3-epoxypropyltrimethylammonium chloride or an equivalent chlorohydrin-functional cationizing agent is used by about 90-1100 g per kg starch solids, and a catalyst is added to the slurry. The reaction is carried out at a high solids content of 40-80%, preferably 50-60%, in at least two successive steps, in the first of which a temperature of about 5-40 ° C. is maintained, and in the second step a temperature of about 70-180 ° C.

Abstract: A method for producing starch solutions of high cation equivalent value with a DS of 0.1-1.0) is provided. The starch to be cationized is slurried to form a suspension of about 10-80% solids content in an aqueous mixture of a cationizing agent. In the cationization chlorohydrin-functional cationizing agent is used by about 90-1100 g per kg starch solids, and a catalyst is added to the slurry. The reaction is carried out at a high solids content of 40-80% in at least two steps, in the first of which a temperature of about 5-40° C. in maintained, and in the second step a temperature of about 70-180° C.

Abstract: A method for internal sizing of paper using cationic starch is provided. The starch used is cationized with a mixture of epichlorhydrin, trimethylamine, and mono-or dimethylamine or N,N,N′,N′-tetramethylethylenediamine. Cationizing results in a higher molecular size of the starch, which has e.g. a beneficial effect on dewatering on the paper machine forming wire.