Silver i ytbeläggningar - Funktion och miljöpåverkan

Sammanfattning: The aim of this diploma work was to investigate whether the use of silver in coatings can be an alternative to the biocidal products available on the market today, as well as if silver in coatings for indoor use may be an option to reduce the spread of infections in hospitals. The thesis has been made as a literature study in which facts about microbial growth has been compiled. Furthermore, research on ionic colloidal silver and silver nanoparticles was analyzed to investigate if its properties could be effective against the investigated purpose. Since silver is a heavy metal, research about its toxicity has been analyzed to know how the processes of leaching works today. The results of the study showed that silver as an antimicrobial substance and as an alternative biocid has an efficiency which is worth more research. Ionic colloidal silver was considered as an effective treatment for inhibiting bacterial growth such as Clostrium difficile which is a common infection caused by antibiotic treatment that by the past eight years has caused 572 deaths in Sweden. Silver nanoparticles demonstrated an efficacy against different types of mirco-algae but needs to be tested furthermore against blue stain, mold and fungi. New methods need to be found in order to more effectively bind the silver in the coating matrix to reduce or prevent the process of leaching that today disseminate silver and nano materials to the aquatic enivronment. If this can be fullfilled, we can reach a stage where the biocidal products can inhibit growth for a longer time, but with less leaching, than the organic biocides available on the market today does.