There are different methods for the label adhesion process required for IML.

Blow molding is typically used to produce containers or bottles that are made of plastic and are hollow – think household cleaning products or liquid laundry detergent. A plastic tube (which will eventually become the vessel, bottle, tub or container) is heated until it inflates – imagine blowing up a balloon. A mold is then clamped down around the plastic to give it it’s final shape. The mold will already have the label inside it, with the back side of the label facing the oncoming hot plastic (so that the label is the right way round on the final container). The residual heat from the plastic fuses the label to the container.

With injection molding, plastic is again used to make containers which are plastic and hollow – but this time it might be something more like ice cream tubs, or yoghurt pots. During the injection molding process, the heated plastic is injected under high pressure into a mold which again contains the label(s). The hot plastic cools off and hardens with the label then seamlessly attached without glue.