Wetlaid nonwovens are manufactured using a hydrodynamic process which is taken from the wet processes of papermaking. Similar to the papermaking process, the wetlaid process for nonwovens uses a filtration plant in which fibres are suspended in a revolving drum-like sieve. The conditions for producing a homogenous length of web are an even distribution of the fibres suspended in the water and an even dispersion.
Fibres of up to 25mm in length are used. Contrary to other web forming processes at least a pre-binding process is carried out prior to the web formation itself in wetlaid technology. For this either the suspension of the flocculated binder or special binder fibres is added. The binding strength is activated during the drying process. The process of wet binding of dry nonwovens is also used. Finally further bonding and refining processes can be carried out.