Electrostatic discharge materials

Conductive ESD bag with a network card inside
ESD shoes

Electrostatic discharge materials (ESD materials) are plastics that reduce static electricity to protect electrostatic-sensitive devices (ESD) or contain flammable liquids or gases.

Materials

ESD materials are generally subdivided into categories with related properties: Anti-Static, Conductive, and Dissipative.[1]

Ohms Per Square Material Description
> 1013
Insulative
Insulators and Base Polymers. Not an ESD material
109 to 1012
Anti-Static
Initial charges are suppressed. Typically pink color.
105 to 109
Dissipative
No or low initial charge. Prevents discharge to or from human contact
103 to 105
Conductive
No initial charge. Provides path for charge to bleed-off. Typically black color.
1 to 103
Shielding
10−3 to 1
Carbons
Carbon powders and fiber
< 10−3
Metals

Insulative

Insulative materials prevent or limit the flow of electrons across their surface or through their volume. Insulative materials have a high electrical resistance and are difficult to ground, thus are not ESD materials. Static charges remain in place on these materials for a very long time.

Anti-Static

Anti-static materials are generally referred to as any material which inhibits triboelectric charging. This kind of charging is the buildup of an electric charge by the rubbing or contact with another material. One type of anti-static packaging material is commonly referred to as Pink Poly. It is a clear pink (hot pink) polyethylene that is available as a film for bags, bubble pack, or foam.

Dissipative

Dissipative materials allow the charges to flow to ground more slowly in a more controlled manner than with conductive materials.

Conductive

Conductive materials have a low electrical resistance, thus electrons flow easily across the surface or through these materials. Charges go to ground or to another conductive object that the material contacts.

See also

References

Further reading

External links

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