Die Cutting
In-mold labels can be die cut using a variety of techniques. Some companies develop their own die cutting equipment based on that companies experience with die cutting. Schober, Polar, Bloomer, Bobst, and PMC are just a few of the companies that produce the thin film die cutting equipment.
Some of the die cutting techniques take stacks of printed sheets and first cut the square or rectangle shaped stacks of labels. These stacks are then fed into die cutting equipment that forces the stacks through dies and cuts many labels simultaneously. Whereas this technique is fast it generally results in the least accurate die cut label. This technique is referred to as “chunk and cut”.
Rotary die cutting cuts the labels a single layer at a time and as many labels as can be printed across the substrate. This “rotary die cut” technique is typically more accurate than the “chunk and cut” technique but results in “angel hair” as the die wears, because the dies actually do a compression cut in contrast to a virtual cut of the material.
Cutting labels individually using a line to line die is typically the most accurate die cutting technique. These systems can be offline or on the end of the line of the printing equipment.
Rotary die cutting or individual die cutting can be used when incorporating “cut in place”.
“Cut in place” (CIP) is a technique used to die cut the labels next to the injection mold machine at the molder. This technique typically results in a 30% reduction in the cost of the in-mold labels and virtually eliminates problems associated with label curl and results in a more sustainable product by eliminating all the packaging materials.