Applications of Hydrocharging Electret Technology in Air Filtration Media

1. Household Air-Purifier Filters

This is the most common application. Hydrocharged melt-blown filters can achieve filtration efficiency above 95% for 0.3 μm particles—approaching the HEPA standard—without significantly increasing airflow resistance. Electrostatic capture requires no additional consumables and meets household purifiers’ need for low noise and low energy consumption. These filters are often used in combined prefilter and medium-efficiency filter assemblies for bedroom and living-room purifiers.

2. Fresh-Air System Filters

Hydrocharged filters are well suited to removing particles from outdoor air brought into fresh-air ventilation systems because of their high dust-holding capacity and long service life. Their electrostatic layer is less likely to lose effectiveness when humidity changes, such as during the rainy season, and is more resistant to environmental interference than conventional electrospun filters. They can be used in the medium-efficiency stage of a fresh-air system to reduce the load on the HEPA filter and extend the overall replacement interval.

3. Vehicle Air Filtration

These filters are suitable for automotive cabin-air filters and in-vehicle air purifiers. Their lightweight construction, based on a thinner substrate, fits the limited installation space in vehicles. They efficiently filter PM2.5 from exhaust emissions and resuspended road dust, while their electrostatic capture produces no ozone, avoiding secondary pollution inside the vehicle and meeting health requirements for automotive applications.

4. Indoor Ventilation and Air-Conditioning Filters

These filters can be used as return-air filters in household and commercial central air-conditioning systems. Compared with ordinary nonwoven filters, hydrocharged filters capture more suspended particles at lower airflow resistance, reducing dust buildup and bacterial growth inside air-conditioning systems. They are particularly suitable for ventilation systems in densely occupied places such as offices and schools.

5. Supplemental Filtration for Specialized Applications

The technology is also used to a limited extent in protective masks, such as KN95-grade masks, in areas frequently affected by smog. Hydrocharging increases the electrostatic attraction of the inner melt-blown layer, improving its ability to block fine particles while preserving breathability better than conventional electret processes such as corona charging.