With which alkyd phenolic resin systems can we achieve good adhesion to plastic materials ?
adhesion to plastics depends on many factors, including the chemical nature of the substrate ( i.e. what kind of plastic ) and its surface finish and of course the composition of the paint. Particular care should be taken to ascertain whether the plastic is affected by the solvents contained in the paint. Air drying systems based on long oil or
medium oil alkydson their own or in conjunction with other resins have proved successful.
Paint containing only aliphatic solvents or blends of aliphatic solvents and alcohols are also recommended. The hardness and adhesion of the paint can be increased by blending natural resin modified phenolic resins or alkylphenol resins. some of these blends have to be cooked, whilst others are compatible so that they can be mixed at room temperature. The colour of phenolic resins and their poor light stability can sometimes be a disadvantage.