In addition to binding together the different layers of a membrane switch, 3M laminated adhesives are also used to hold the layers together. Double-liner adhesives are specially constructed sheets of non-adhesive carriers held together by a 3M pressure sensitive adhesive. This design gives the spacer film the structural integrity to be die-cut in intricate patterns without breaks. The two poles of the membrane switch, screen-printed on polyester film in polymer thick film, can then make contact through the die-cut window upon the application of pressure.

3M membrane switch spacers are available in roll or sheet form in a variety of thicknesses and liner types.

Densified kraft liners provide stiffness for rotary die-cutting and clean edges. Polycoated kraft liners are moisture-sealed with an extra polymer coating on both sides for reduced warping and wrinkling. Polycoated liners are suitable for clean room application, making them the spacer films of choice for membrane switches used in medical equipment. Lay flat liners provide more stiffness to the spacer film for better handling, easy kiss-cut die-cutting, fewer liner breaks, easier lamination without wrinkles, and more versatile product configuration. Film liners give spacer films moisture resistance, clean die-cuts for easy visual inspection, and clean room suitability. Film liners are also recommended for spacer films in membrane switches used in medical equipment.

For full information, please return to the Membrane Switch Spacers product page.