TS EN ISO 19403-5

TS EN ISO 19403-5 is a part of the wettability series for paints and varnishes and focuses on determining the polar and dispersive fractions of a liquid’s surface tension from contact angle measurements on a solid surface. In practical terms, it addresses how a coating liquid interacts with a surface, since these surface-tension components influence wetting, spreading and the tendency of a liquid to adhere or remain beaded.

Contact angle as a wetting indicator

The contact angle describes how far a droplet spreads on a solid surface. In general technical use, a lower contact angle is associated with better wetting, while a higher angle indicates poorer wetting of that surface by the liquid. This standard’s specific focus is on solids with only a dispersive contribution to surface energy, which provides a suitable basis for separating the liquid’s polar and dispersive surface-tension fractions from optical contact-angle data.

Where this method is used

The document specifies a test method that can be applied to characterize liquid coating materials. In wider coating technology, such measurements are used to compare formulations, assess the influence of surface preparation, and interpret how a liquid may behave before application. The listing itself does not state detailed sample-preparation steps, numerical limits or acceptance criteria, so those points must be read in the full document rather than assumed from the title alone.