The project revealed that contamination of paint was not due to bacteria being resistant to biocides but that biofilm residing at hard-to-clean sites inside the production system was the main reason leading to failed in-can preservation. This finding led to modernization of the production facility, increased focus on cleaning procedures, including deployment of cleaning pigs and improved monitoring of the microbial status of raw materials and the production system. Together these initiatives resulted in minimized contamination of produced paint and a reduction in the number of claims regarding ’rotten paint’. In parallel to improved hygiene, the project group worked to improve the antimicrobial efficacy of biocides for in-can preservation. In this context a new method for fast and reliable testing of the resilience of preserved paint against microbial growth was developed. This method was extensively used to aid the development of improved paint formulations with respect to avoid microbial deterioration. The new paint formulations included implementation of new biocide-packages for more traditional paints with lower biocide concentrations Furthermore new developed paint using medium to high pH as antimicrobial hurdle gave promising results. While marked improvements have been achieved during the project, for the near future it is obvious that in-can preservation of paints remains necessary. However, the tools for preservation may become even more environmentally and societally sustainable.
Eco-friendly production of waterborne paint
The aim of this project was to improve the sustainability of paint production through reduced use of biocides and minimisation of resources. The biocides are used as in-can preservatives to avoid spoilage of the paints due to growth of bacteria. But due to recent years’ restrictive legislation in the area, the number of biocides has been reduced, and the risk of microbiological spoilage of paint may thus increase. With the purpose of reducing the risk, the project has focused on the causes of spoilage and explored possible solutions to reduce the use of biocides. MUDP rapport.