MOLDING - ANTISTATIC, STATIC DISSIPATIVE, CONDUCTIVE & STATIC SHIELDING MOLDING
Antistatic (1x10e9 to 1x10e12 ohm surface resistivity) This is where all of the old additive packages used to put plastics and they were activated by humidity in the air, and easily washed off (they came back over time, but also became less effective as time went by). Today this range can be made permanent by using inherently dissipative polymer (IDP) alloys, and they are non-humidity dependent and will not be washed off of the surface.
Static Dissipative (1x10e6 to 1x10e9 ohm surface resistivity) The actual EIA Standard definition designates these as 1x10e11 ohm, but the industry actually prefers to 1x10e6 to 1x10e9 ohm, but will take 1x10e9 to 1x10e11 ohm if cost is significantly lower. These products can be made with carefully controlled carbon black content, IDP alloys or with inherently conductive polymer (ICP) alloys.
Conductive (<1x10e3 ohm-cm volume resistivity) These are compounds that can be made with carbon black, carbon fiber (somewhat colorable), and stainless steel fibers (colorable).
Static Shielding (<1x10e3 ohm-cm resistivity) As a compound becomes more conductive it can actually shield something from electromagnetic interference (EMI), or radio frequency interference (RFI). As the compound becomes more conductive, the better the shield. A generalized relationship between volume resistivity and dB shielding effectiveness (SE) is as follows (Please note that thickness comes into play, but this generalization works for materials from about 0.060 to 0.125 thick).
1000 ohm-cm10 dB SE
100 ohm-cm20 dB SE
10 ohm-cm30 dB SE
1 ohm-cm40 dB SE
0.1 ohm-cm60 dB SE
0.01 ohm-cm80 dB SE