Vinyl decal materials are made from two distinctly different manufacturing processes. One is called cast vinyl and the other is calendared vinyl. While both look great when freshly installed, one will outlast the other and the difference will be obvious with time and environmental exposure.
Why calendered vinyl isn't the best choice for vehicles.
Calendered vinyl is manufactured in a process that takes less raw material, energy and labor to produce. These associated cost savings become evident in the lifespan of the decal. Typically calendered vinyl is referred to as "temporary" or "short-term" for decals. The way calendered vinyl is made causes it to have a memory. This means that it will attempt to return to its original form by shrinking. The lifespan of a calendered vinyl decal is anywhere between 6 months to 3 years.
Cast vinyl is the best choice for vehicle decals.
While the manufacturing process of cast vinyl does require more of an expense, the benefits far out weigh calendered due to the much longer lifespan. With cast vinyl, you can expect 3-6 years printed and 7 or more years unprinted. This is because cast vinyl doesn't have the memory problems calendered vinyl does, making it a much better choice for vehicle applications.