Thermoforming FAQ

What is Thermoforming?
Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product. The sheet, roll stock or “film” when referring to thinner gauges and certain material types, is heated to a high-enough temperature that permits it to be stretched into or onto a mold, utilizing positive and negative pressures and cooled to a finished shape.

Is thermoforming different than injection molding or blow molding?
Yes, all three are different technologies that can in the end produce very similar products. Injection molding requires the material typically plastic pellets to be 100% melted to liquid form, it is then injected into a mold at very high pressure. Blow molding starts with the fabrication of a starting tube called a parison. The parison can be pre-manufactured or extruded in line. The parison is heated, then filled with compressed air to inflate the parison to fill the mold. Thermoforming is considered the simplest and most economical forming type.

What is plug assist?
Plug assist is a technique where a plug roughly shaped like the final product pushes into the heated film to assist in the stretching of the material. It is very helpful in deep draw situations and to maintain a more consistent material thickness of the formed product.

What is negative draft or negative angle forming?
In thermoforming the product (and mold) are typically wider at the top and taper to narrower width, for example a plastic drinking cup. Or the side walls are perfectly vertical, for example a portion pack of butter. The two previous examples ustilize a very simple single piece mold, as the parts naturally have room to be easily removed from the mold. In negative draft thermofoming, we have the flexibility to work outside of these typical restrictions, by creating a two piece mold that can open to release the parts, we can form shapes that are wider at the bottom, than at the top, for example a ball shape.

What types of materials can be thermoformed?
PS-Polystyrene, PP-Polypropylene, PET-polyethylene terephthalate, PVC-Polyvinyl chloride, and more custom compounds depending on the application requirements.

Is it possible to produce aseptic packages using inline form, fill, seal (FFS)?
Yes, due to Illig’s modular design, we were able to add a sterile cleaning and filling section to our machine, allowing us to form the container, clean/sterilize it, fill, and seal all in one machine.