Ytbehandling baserad på hampolja

Sammanfattning: The varieties of paint are today very big, but many of the more popular paints are less than environmental friendly. The uses of fossilized fuel in paints are common because these paints dry fast and are color true. It would be beneficial for the environment if more renewable source were used to produce paint. Linseed oil is an old base for oil paints. It is renewable and easily procured. But linseed oils have some aspects that give it a bad reputation. There are problems with the slow drying and the color turning yellow when exposed to darkness for long periods of time. Researchers at KTH have connected the yellowing to linolenic acid, one of the common fatty acids in linseed oil (Svensson, M. Johansson, M, Stenberg, C. Samuelsson, J. 2003). Hempseed oil is also a drying oil like linseed, but hempseed oil contains a larger amount of the fatty acid linoleic acid and a smaller amount of linolenic acid (http://en.wikipedia.org/wiki/Hempseed_oil). This might mean that oil paint based on hempseed-oil instead of linseed-oil might have fewer problems with yellowing.Experiments with the two oils have been executed side by side in order to compare results. Two oil paints have also been produced and tested. Test pieces painted with the two different oil paints were exposed to moisture, daylight and complete darkness and then compared.