Thermoforming is a process of transforming plastics.
It appears to be a simpler technique that injection molding because it avoids the problems of mixing plastics. Nevertheless, there are difficulties that arise precisely from the fact that it must hot deform a raw material that has already undergone transformations such as extrusion, calendering or casting to make it into a film or sheet.
The plastic memory of the material due to the internal tensioning it was subjected to in the preceding transformation processes means that its deformation leads to uneven stretching that is difficult to control. The major difficulty has to do with the repeatability of the operation and, thus, with the technical characteristics of the product made.
Careful design of the equipment, experience in the selection of molding methods, control of every step of the process and precise quality control allow achieving the required result.