2016 年 67 巻 7 号 p. 375-379
Stain resistance is a key performance criterion of pre-painted steel sheet used outdoors. The addition of organosilicate to paint is known to prevent a paint film from staining by hydrophilicity. To clarify the mechanisms related to this technology, we investigated the stain-resistance effects of adding organosilicate to paint used for pre-painted steel sheets. We considered them from the point of solid surface tension, which was divided into three force elements: hydrogen bond force, dipole-dipole force, and dispersion force.
Results show that the organosilicate concentrated near the paint film surface, which exhibited good stain resistance. The hydrogen bond force was much stronger than any other force element of solid surface tension on that film before and after the exposure test. Therefore, the adhesion work between water and that film was greater than between the stain and that film.