What Is an Antistatic Sheet?
An antistatic sheet is a sheet that prevents static electricity on the surface of a material. Plastics (films) accumulate static electricity (charging) easily, which can cause electrostatic interference and malfunctions if there are electronic components in the vicinity. It can also cause static ignition of organic materials and adsorption of electrically charged dust.
Antistatic sheets are available in two types: surfactant-added type, in which an antistatic agent floats on the surface, and non-surfactant polymer type, in which the material itself has an antistatic effect.
Applications of Antistatic Sheets
Antistatic sheets are often used as packaging materials for electronic parts, electronic devices, and substrates that are sensitive to static electricity. They are also used as packaging materials for powder and dust-sensitive precision parts.
In addition to films, antistatic plastics are also used to prevent dust and products from adhering to covers in fields requiring a high level of cleanliness, such as semiconductor, medical, and food manufacturing.
They are also used as apron-type protective clothing with sleeves in the medical field.
Principle of Antistatic Sheets
Antistatic sheets with a surfactant are kneaded with an antistatic agent), a substance that has both hydrophilic groups that are easily absorbed by water and hydrophobic groups that are easily absorbed by oil. The surfactant appears on the surface due to the bleeding phenomenon, and the hydrophilic groups adhere to moisture in the air to form a film of water on the surface. This water film contains free electric charges and is conductive. The free charge in this film neutralizes the electric charge, thus eliminating static electricity. Since the antistatic effect is based on the water film that can be formed on the surface, the effect varies depending on the humidity. It is not suitable for long-term use because the effect fades over time.
In the continuous antistatic type, special metal ions are added to the material. These metal ions form a conductive circuit within the plastic as a conductive substance, creating a pathway for static electricity to escape, thereby producing an antistatic effect. In many cases, this type has a transparent blue appearance. It has a semi-permanent antistatic effect and is not easily affected by the surrounding environment, but it is more expensive than the surfactant-added type.