Process for producing sized paper or cardboard with dyes or optical brighteners and epoxide-amine-polyamide reaction products

摘要

A process for producing paper or cardboard which is sized in the pulp with epoxide-amine-polyamide reaction products is disclosed. In this process there are added to the fibre suspension (A) at least one water-soluble, anionic, substantive direct dye and/or optical brightener, followed by (B) at least one water-soluble or water-dispersible salt of an epoxide-amine-polyamide reaction product, whereupon the fibre suspension is further processed into paper or into cardboard.