To produce a container with a complex shape, we would need all the mechanical, pneumatic, and vacuum systems to be perfectly integrated and synchronized, thereby ensuring that the heated sheet can take on the desired shape uniformly, resulting in a finish that is visually appealing to the customer. However, there would still be one issue to resolve, because even if we could form the perfect container, a very important detail in thermoforming is the demolding stage. This stage occurs at the end of the thermoforming process; it is when the container exits the mold that shapes it (it is demolded) and moves on to the next station, typically the one where the product is dispensed
. As a general rule, to ensure the container can be demolded, the mold is designed with a draft angle that tapers toward the container extraction area, allowing the container to exit the mold smoothly and continue the automated process without interruption.
When the desired geometry is so complex that it does not allow for a draft angle on the container, thermoforming molds with full or partial opening are designed; these can be operated via vertical or lateral movements. Furthermore, depending on the desired outcome, mechanisms can even be moved within the mold’s internal cavities—all without compromising the aesthetic finish of the container’s visible surface.
There is one detail to note regarding these thermoforming mold systems with opening mechanisms: they create a mark on the thermoformed container along the mold’s opening and/or closing seam, which is called the parting line. This line can be minimized depending on the finish applied to the mold.