Hot melt adhesives based on reactive polyurethane (PUR) currently represent the highest quality level in edgebanding. These moisture-curing hot melt adhesives require more caution during processing. They are supplied in moisture-proof packaging units and processed in special melting units protected from exposure to ambient humidity.
The newly available PUR in granulate form allows an easy entry into these kind of adhesives. The granulate form is not only interesting for processors new to the PUR hot melt technology, but above all also for small industrial companies that absolutely require PUR edgebanding for specific objects.
Jowat SE has developed a patented manufacturing method for moisture-reactive hot melt adhesives in granulate form. The tried and proven adhesives from the product family Jowatherm-Reaktant® are suitable for bonding regular edgebands of all kinds.
In underwater granulation, the molten material to be granulated is extruded through the holes of a perforated plate into a cooling liquid (water in this case) and the string of extruded material is then cut off by fast rotating knives. The temperature difference between the hot adhesive and the cold water causes the adhesive string to contract instantly after it is cut off by the knives, leading to the typical ball shape of the underwater granulate. The round granules are characterised by an optimum flow behaviour and minimum contact surface, and therefore provide major benefits in dosing and dispensing compared to other geometries.