Effects of Surface Segregation of resin on Properties of Polyester Prepainted Steel Sheets

Abstract

The relationships between surface properties and surface compositions have been investigated for two types of polyestermelamine paint films. The surface content of melamine has been estimated from XPS nitrogen-peak intensities. The surface segregation of melamine on the paint films was observed under hightemperature and short-time curing as a practical condition.
The contact angle of water and the adhesiveness to urethan adhesive depended not upon polyester resin but upon surface melamine content. The stain resistance of marker ink was improved as surface melamine content increased. The stain resistance also depended upon the type of polyester resin.
These phenomena indicate that the surface properties such as the contact angle of water and the adhesiveness are effected by the surface composition within the sampling depth of XPS (-10 nm), and that the stain resistance is influenced by the interior structure of paint films.