Made to measure: hook-and-loop or roll
The three-layer structure
- 1Outer mesh
The breathable outer layer. It withstands sun and weather, protects the membrane and keeps its shape after cutting.
- 2Nanofiber membrane
A web of fibres much finer than a human hair. It holds back smoke, dust, allergens and spores while letting air through.
- 3Inner mesh
The breathable inner layer that carries the filter and gives it strength. It stands up to washing and daily use.
The layers are permanently bonded, so they do not separate when you cut or fit the filter. The edges you cut do not fray, so you can buy it by the roll and cut it to your own size.
What is nanofiber?
Nanofiber is the name for fibres much finer than a human hair. Laid on top of one another, these fibres form a web like a spider’s web, with a great many tiny pores. Because there are so many pores, air easily finds its way through; because the pores are small, dust and pollen particles in the air get caught in the web.
The same technology is used in air filters and protective masks. In the window filter, this web is set inside a membrane as thin and flexible as an insect screen.
How are particles held back?
The filter works purely physically, without using any chemicals. As air passes through the filter, the particles in it are held back in three ways:
- Sieving: Particles larger than the gaps between fibres, such as pollen grains and coarse dust, stay directly on the surface of the web.
- Impaction: Where the air changes direction, heavier particles cannot follow the flow and hit the fibres and stick.
- Interception: Very small particles touch the fibres and stick as they move irregularly in the air.
That is why the filter holds back not only particles larger than its pores but also a large share of the fine dust floating in the air.
Particles stay in the filter, air passes through.
Smoke, dust, allergens and spores stay in the nanofiber membrane.
