A simple method to measure the surface energy of various materials, such as plastic, glass, and recycled or composite materials, is the determination using test inks. Plasmatreat test inks are an excellent tool for surface determination, quality assurance during ongoing production, and determination of accurate parameters for plasma treatment.
All Plasmatreat test inks are manufactured according to DIN Draft 53364 or ISO 8296.
The test ink is applied quickly to the surface using the integrated brush of the bottle. Start with an ink with a high surface energy (such as 72 mN/m) directly after the pretreatment. If the brush stroke edges are stable for two seconds, the surface is easily wettable. Then, the surface energy of the substrate is at least equal to the value of the test ink. If the brush strokes of the test ink contract, the next lower test ink should be used. This way, you are gradually approaching the surface energy value of your material. The surface energy of the material is equal to the value of the test ink last used that showed good wetting for at least 2 seconds.
Ethanol test inks (C Series)
Suitable for all common surfaces. Non-toxic, non-harmful.
10ml bottles, available from 28 to 72 mN/m (in increments of 2 mN/m)
The maximum measurement error is 2 mN/m. For test series with multiple measurements, the error tolerances are reduced accordingly. As with any measurement process, the determination of surface energy using test inks also requires a critical approach to the measurement results. The measurement values obtained with the test ink method for measuring surface energy are relative values and have limited comparability with other methods. The calculated surface energy can only be a measure of the current state of the substrate because, according to experience, surface energy decreases with storage time.