Hot melt adhesive melts at relatively high temperatures averaging approx. 100 ° C; it is usually processed at temperatures of approx. 160 ° C. The melting point is usually determined using the Ring & Ball method, in which a steel ball is dropped through a hot-melt adhesive film in an oil bath as the temperature rises. The temperature at which the ball touches the metal plate underneath is determined as the melting point.
Melting point or melting range
Some melts have a short melting range, the steel ball z. B. drops slightly at 100 ° C and has already completely dropped at 101 ° C. Other hot melt adhesives can have a long melting range that starts at 70 ° C but only drops completely at 120 ° C.
Different hot melt adhesives available
There are many different hot melt adhesives, both PSA pressure sensitive hot melts and granular hot melt adhesives. The melting points are generally between 50 ° C and 160 ° C.