Die-Cutting Polyester Film

Die-Cutting Polyester Film
Polyester films provide excellent strength, durability and appearance for graphic and tactile layers of membrane switches when key die-cutting parameters are monitored:

Dies should be steel rule of a medium hardness (450 VPN) with a ground edge and a 2 point rule gauge. For cutting polyester film laminates, a side bevel profile should be used with the long edge facing the waste; for single layers of thick gauge polyester film, a long center bevel is recommended.

Cutting conditions for polyester films can affect quality. The press should be aligned at set-up with a platen free of dishing. Die and polyester film should be heated uniformly to less than 155.25 degrees F. Polyester film should be cut with textured surfaces facing the die before lamination to other layers.

Ejector foam and covered make-ready can minimize edge delamination. A hard foam or rubber composite with a 3 to 5 mil polyester film covering should cover the die area. Blade life can be extended by covering the steel make-ready with Formica® or vulcanized fiberboard.