When it comes to filtration, a basic distinction is made between liquid and gas filtration. In both cases, particles, dust, viruses, pollen, macromolecules, microorganisms or the like are mechanically filtered out of either a fluid or gas.

Technical fibres are now used in a wide variety of filter media, such as: Filtration papers, felts, fabrics, etc. The short fibres from STW are mainly used in filter papers.

Fibres can significantly influence important technical properties such as air permeability or the tear strength of the filter media. Fibrillated fibres are used to create defined fibre surfaces of up to 50 m² per gramme of fibre, which determine the properties.

Depending on the type of fibre used, the zeta potential of the filter medium can also be adjusted to optimise the efficiency of the separation effect.
The filter components used in the medical field must meet particularly high purity requirements and usually require FDA and/or drinking water approval.

In the past, STW developed a product range of different types of fibres to meet a wide variety of filtration requirements.