abstract |
An aqueous primer composition comprising a copolymer wherein a cationic monomer, a specific alkoxysilane monomer, a silane macromonomer and an ethylenically unsaturated monomer are contained in aqueous medium. For this reason, regardless of the alkalinity of the substrate, the aqueous primer composition can form a highly water-resistant, alkali-resistant, tough film. Furthermore, compared with the prior art, a higher concentration and a lower viscosity, so that the resulting primer composition shows excellent penetration into the substrate at high concentration and provides for sufficient substrate-reinforcing and water-proofing effects. Moreover, when forming a film thereby and forming a finish layer thereon, this composition shows a high affinity for the top coating or adhesive to insure a firm integration of the finish layer with the substrate surface. |