What can we do against yellowing alkyd resins?
There are various ways of counteracting the tendency of alkyds to become yellow. One can, for example, use optical brighteners which convert UV rays into visible, blue-violet light which neutralises the yellow tinge. These products are, however, usually quite expensive and their effectiveness often leaves much to be desired. A preferable alternative would be to use a binder that is non-yellowing.
Poor light fastness is usually due to the presence of unreacted double bonds. ln the case of alkyd paints, these originate from the unsaturated fatty acids contained in the oil. When formulating alkyd paints it is therefore important to ensure that the double bonds in the fatty acid undergo complete oxidative crosslinkage during film formation, e.g. by adding coconut or castor oil.
Yellowing Alkyd Resins
Blog, Updated at: 5:22 PM
