Tack, or quick stick, is the ability of a material to adhere instantaneously to a solid surface when brought into contact under very light pressure. “Instantaneous adherence” indicate that the tack is a measure of the capacity of the adhesive to make the bond. Methods used for measuring tack however rely on measuring the energy required to break the bond made in short time and low pressure. So tack is defined by the test used in its determination, it is not a basic property of the adhesive, but a composite response of the adhesive’s bulk and surface properties.