Abstract:

Paper is a material that is easily biodegradable. The most active group of microorganisms responsible for biodegradation processes affecting paper are moulds. In order to prevent this unfavorable impact, various methods are used, including biocides, which added to paper during the production process to protect the final product. In this study, the following ionic liquids were applied: benzalkonium nitrate(V), benzalkonium DL-lactate, and didecylodimethylammonium DL-lactate. They were added (in a concentration of 3% and 5%) to paper samples made of the following pulp grades: pine bleached kraft pulp (pine BKP), birch bleached kraft pulp (birch BKP), recovered fibres and CTMP. The antifungal activity of paper was assessed using a qualitative and a quantitative method with strains A. niger, A. versicolor, P. chrysogenum and P. aurantiogriseum. The most resistant strain to the ionic liquid activity was Aspergillus niger. The best antimicrobial effect was shown by paper samples made of pine BKP with biocides. The weakest effect was obtained for the CTMP-based paper.