What are fisheyes? / What causes fisheyes?
Fisheyes is a term used by label printers to describe randomly distributed ring-shaped marks that appear in most self-wounds. Fisheyes are a characteristic feature of self-wound films caused by air entrapment between the film and adhesive during the winding processes. As the roll builds up, the pressure on these ‘air pockets’ causes regional adhesive flow, creating the fisheye appearance.
Pressure Sensitive Adhesives (PSAs) are adhesives which form a bond when pressure is applied to marry the adhesive with the adherend (or substrate). No solvent, water, or heat is needed to activate the adhesive. They are used in pressure sensitive tapes, labels, note pads, automobile trim and a wide variety of other products.
As the name “pressure sensitive” indicates, the degree of bond is influenced by the amount of pressure which is used to apply the adhesive to the surface. Surface factors such as smoothness, surface energy, removal of contaminants, etc. are also important to proper bonding.