Test Method For Corona-Treated Polymer Films Using Water Contact Angle Measurements ASTM D5946

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.

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.
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