Switch contacts 

Switches are usually activated with sliding contacts. Two contact areas at different voltages are there for short-circuited. Switch contacts come in various materials and various shapes. 

Printing of the contact areas with a conductive polymer paste realizes passivation to the copper surface and achieves low contact resistance, which remains constant throughout the service life. 

This contact resistance dependents on the design of the slider (geometry, contact pressure, etc.) as well and is typically <20 Ω.