PROCESS FOR THE MANUFACTURE OF PAPER OR CARDBOARD WHICH IS SIZED UNDER ALKALINE OR NEUTRAL CONDITIONS WITH ANIONIC HYDROPHOBIC SIZING AGENTS AND CATIONIC RETENSION AIDS

摘要

Sizing agents devoid of anhydride groups, some of which are known and others are novel compounds, and which carry a single N,N-C6-C22alkyl(or alkenyl)amide group as hydrophobic substituent and at least one anionic group, in particular N,N-C6-C22dialkyl or N,N-C6-C22dialkenyl partial amides of a dicarboxylic acid, tricarboxylic acid or sulfocarboxylic acid, or the salts thereof, are particularly suitable, together with commercially available retention aids, for use in a process for pulp-sizing paper or cardboard at a pH of at least 6.5 of the fibre suspension, in the absence of e.g. aluminium sulfate, or in a process for surface-sizing paper.