Carbon Pill, also known asCarbon PuckandElectric Conductive Pill, is the heart thatconducting interface between keypadandPCB,which usuallymade by mixing 60% VMQ and 40% conductive carbon black, produced by die-cut molding and compression molding. Carbon Pillsare widely used for control device products in switch system such as phone keypad, Remote Keypads, etc.
Conductive carbon pill’s quality affects silicone keypad quality During vulcanizing process, low temperature and short vulcanizing time wouldn affect a good combination of carbon pills and silicone keypads. Even carbon pills fall off the rubber keypad. High mold temperature will cause big liquidity of silicone raw material in the mold, which lead to forming in mold. This is also a reason for bad combination of carbon pills and rubber keypads. Incomplete exhaust would result in air traps on rubber buttons and carbon pills falling off. Low molding pressure and insufficient silicone material also cause that carbon pills fall off the rubber keypad.
There are two kinds of carbon pills, one with textured surface, the other with smooth surface.Both carbon pills are in the same effect, used for wear resistant and long lasting life.