Contact Angle Measurements ASTM D5946

Scope:
Polymer films are often used to create decorative and informative graphics for applications such as automobile instrument panels and consumer electronics. The decoration is created by a surface coating consisting of inks, paints, clear coats, etc. In some cases a secondary operation, such as corona treatment, is necessary to promote surface adhesion. The contact angle of a water drop on the polymer surface is an indirect measurement of the surface's ability to accept and hold a coating.

Test Procedure:
A strip of the test material is inserted into the Goniometer. The syringe on top applies a single drop of deionized water onto the test specimen. An enlarged projection of the water drop is displayed on a gauge on the end of the Goniometer . The gauge is then adjusted to measure the angle between the material and the edge of the drop.

Specimen size:
The test material is cut into 15 mm (0.5") strips to fit in the Goniometer. Specimen thickness cannot be greater than 2.5 mm.

Data:
The test result is an angular measurement in degrees, which can be converted into the surface energy for purified DI water utilizing a table in ASTM D5946.

**Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. Due to copyright restrictions, we are not able to provide copies of standards. Standards can be obtained from appropriate standards authorities.