The key-top type of keypads are based on molded silicone rubber. The symbols and graphics on the keypad are printed. The printing can be a positive (symbols printed) or negative printing (area around symbols is printed). The ink that is used is also based on silicone rubber and has a long-life due to the degree of cross-linking with the silicone key-top.
For special long life requirements Shin-Etsu can offer special protective layers/coatings:
Several colors (translucent and non-translucent) of silicone can be applied.
The KT- and KTP-types are widely used in telecommunication, car-audio, remote control units and instruments.