A paintable primer composition comprising a dispersion, or chip is disclosed. The chip is produced from a dispersion comprising a thermoplastic polymer, a phthalate ester of a C1-C6 alkylated aromaticalcohol, a surfactant and other components selected from a metal carbonate, a white metal oxide pigment, an alkaline earth metal salt of a C9-C20 aliphatic fatty acid, a lower alkyl methacrylate polymer, a solvent and a rust inhibitor. The paintable primer composition is particularly suitable for painting surfaces, such as metals, composite materials and thermoplastic polyolefins including polyethylene, polypropylene, polystyrene, thermoplastic elastomer or ethylene-propylene rubbers. Painting of polyethylene surfaces may be assisted by precoating with an adhesion promoter comprising an aromatic hydrocarbon, a co-polymer of a C2-C6 alkene and a vinyl ester and a chlorinated polyolefin.