Surface tension is the property of a liquid arising from unbalanced molecular forces at or near the surface. If it is higher than the surface energy of a material, the liquid tends to form droplets rather than spread out. Another name for an inkâ€™s surface tension properties is â€˜wettabilityâ€™. Surface tension is normally measured in energy units called dynes/cm. A dyne is the amount of force required to produce an acceleration of 1 cm/sec2 on a mass of 1g.
The dyne level of a material is called its surface energy. If the liquid has a dyne level lower than the materialâ€™s surface energy, then the liquid will spread out over its entire surface in a uniform wet layer. If the inkâ€™s dyne level is equal to or higher than a materialâ€™s dyne level, the liquid will become cohesive and tend to remain in droplets.
Surface test fluids were introduced to give an accurate measurement of graduated surface tension levels. The fluid is applied to the surface or substrate until a satisfactory dyne level is found.
In addition to our family of pre-filled dyne test pens, IEEC continues to offer dyne test solutions in bottles. As part of our standard inventory IEEC offers our ASTM D 2578 compliant dyne test inks from 30 to 70 dyne/cm.