Hot melt adhesives require a delicate balance of formulation components, but the key elements of a typical packaging hot melt adhesive are:
- Polymers (provides strength and flexibility)
- Resins (provides wetting and adhesive properties)
- Waxes (controls viscosity and open time / cure rate).
At a Pressure Sensitive Hot Melt Adhesive (HMPSA) a plasticizer is typically included, which supports elasticity and controls viscosity.
EVA, polyolefin, PSA
There are different types of hot melt adhesives like EVA (Ethylene vinyl acetate) for general bonding, Polyolefin for hard-to-glue plastics and the more modern packaging hot melt adhesive - metallocene (mPO) for high strength in smaller quantities, but we'll cover the different hot melt formulations in a separate article