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For rapid measurement of the surface tension of polyethylene or polypropylene ﬁlms
The adhesive strength of a surface usually depends on its surface tension. In case the surface tension of a surface is much lower than the surface tension of the used ink, the wetting is disrupted. This results in a poorer adhesion.
For this reason the film which has to be printed needs a defined surface tension depending on the respectively used printing ink:
Quick-Test Pen, 38 mN/m
The AFS Quick Test Pen allows you to determine if pretreatment of polyethylene or polypropylene films is sufficient for printing with solvent-based inks. If the surface energy value of a treated film is 38 mN / m (= dyn / cm) or higher, the ink remains as a solid line. If the value is below that, the ink bubbles. The described effects can be illustrated graphically as follows:
Thanks to the solvent-based ink contained in the pen, the applied line dries in just a few seconds and makes wiping unnecessary.