There are many reasons why hot melt fails to bond corrugated paper substrates together.
Some of the reasons are:
- In case erecting and sealing improper compression and substantial memory in the board can be the problem.
- During the winter months the temperature of the corrugated may be low enough to set the adhesive too fast.
- Very often the hot melt is the wrong product with the incorrect open time, set time and chemical makeup.
- The use of recycled paperboard can also present a challenge to the bonding process with hot melt adhesives.
- Too much or too little hot melt may be used
Corrugated bonding with hot melt for case erecting and sealing as well as production of the manufacturers joint should be very easy to accomplish.
Companies who use corrugated cases in their packaging process should evaluate hot melt adhesives off line with small bulk hot melt guns. They should also test the cases in all environments both short and long term.