MONOLITH® Triboelectric, needle punched electrostatic media

How This Electrostatic Filter Media is Different

Monolith filter technology provides a unique and unequaled combination of high efficiency, low pressure drop, and high loading capacity, making it ideally suited to a broad range of applications, including face masks, appliances, automotive cabins and others.

Common filtration mechanisms such as interception and inertial impaction require media to have a small pore size in order to capture small particles efficiently. The disadvantage of this is higher pressure drop and lower loading capacity.

Electrostatic filter media uses electrostatic deposition. This mechanism works using both coulombic forces and dielectrophoretic forces, making it exceptionally effective against particles in the important range between 0.05μ and 5μ. Monolith electrostatic filter media is highly effective in filtering fine particulate, while maintaining very low resistance and high loading capacity. It thus has a productive service life longer than competitive media.

Types of Electrostatic Filter Media

Electrostatic filter media is produced using one of three methods:

  • Induction
  • Corona Effect
  • Triboelectric Effect

Induction and Corona Effect both impart a high voltage charge onto synthetic fibers. PP melt blown web is an example of Corona charged filter media. Fine fibers are typically used to increase surface area, therefore increasing the level of charge. The use of fine fibers will always result in higher airflow resistance and lower particulate loading capacity.

Basic Mechanisms of Particle Filtration

Applications

Face Masks

Vacuum cleaner filters

Automobile cabin filters

Furnace filters

Room air filters

HVAC filters

The Triboelectric Effect is created by placing two polymers with opposite dielectric properties in contact so that they exchange ions and create, once separated, a charge imbalance between the two. This ionic disequilibrium creates a strong electric field at the microscopic level of the filter media.

Because triboelectric charge exists at the microscopic level of filter media, its existence cannot be easily detected by instruments such as a voltage meter. However, the existence of static charge can be determined by measuring the media's increase in filtration efficiency, particularly for submicron particles.

Electrostatic Media Specifications

  • Width: ≤2m (narrower widths can be provided)
  • Media weight: 40g/m2~300g/m2
  • Monolith media can be treated with antimicrobial agents.
  • Monolith media can be laminated with corrosion-protected wire backing, to prevent bypass or media oscillation, and to assure highest structural integrity in heavy-service environments.

0.3u NaCI Particle, TSI 8130