Process for the manufacture of paper or cardboard which is sized under alkaline or neutral conditions with anionic hydrophobic sizing agents and cationic retention aids
US4737239A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1985 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | Sep 9, 2005 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H17/07
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Sizing agents devoid of anhydride groups, some of which are known and others are novel compounds, and which carry a single N,N-C.sub.6 -C.sub.22 alkyl(or alkenyl)amide group as hydrophobic substituent and at least one anionic group, in particular N,N-C.sub.6 -C.sub.22 dialkyl or N,N-C.sub.6 -C.sub.22 dialkenyl 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.