| abstract |
A cationic cellulosic fibre containing between 1 and 30 cationic groups and between 0.1 and 20 aldehyde groups per 100 anhydroglucose units is a suitable basis for producing paper and tissue products without the necessity of using non-biodegradable cationic polymers as wet strength additives. The cationic cellulosic fibre can be obtained by oxidation of the fibre to introduce aldehyde groups, followed by reaction of part of the aldehyde groups with a nitrogen-containing reagent such as betaine hydrazide hydrochloride. The fibre is advantageously combined with an anionic polymer such as monoaldehyde carboxyl-starch or with anionic cyclodextrin. |