The subject of the invention is an antibacterial and antifungal preparation constituting an additive to various materials, in particular, to plastics, containing no nanometal particles, which may be combined with almost any kind of polymers or other materials, from biodegradable polymer packaging, textiles, paints, to hardened PVC, using any processing technology, such as: extrusion, injection moulding, blowing, pressing, lamination, pouring or pumping through capillaries in production of continuous fibre for the textile industry, whereas the biocide contains an active ingredient in the form of a derivative of an acid with a formula shown in drawing (1), where R1 and R2 signify, each separately or both jointly, carboxyl groups, R3 and R4 signify hydrogen or a methyl group, R5, R6, R7 signify hydrogen, X and Y signify interchangeably C and N in the amount of 60 to 85% by weight, and the remaining amount is a composition of inorganic and organic fillers.
