Filter papers
Filter boards
Filter layers

HOME > SUPPLY > Applications > Filtration > Filter layers

Filter layers
The production process

As far as production is concerned, the filter layers consist of a structure of extremely pure special fibres: such structure is created through a process of fibre suspension in water. The dimensions of these special fibres fluctuate from 20 to 50 micron in thickness and 1 to 3 mm in length. In the first stage of mechanical refining they are finely fibrillated and then mixed. By removing the water, they form a structure that, after wet press moulding and drying with steam cylinders, becomes the final product. The so formed sheet presents very tortuous narrow channels (also deriving from the special morphology of the materials used) that retain the contaminating elements in the liquids to be filtered. With this production process, the narrowest channels are located on the surface next to the wire of the machine that produces the layers and from this side the clarified flow will have to come out of the sheet. This funnel structure is essential in order to avoid early exhaustion and assure a long lifetime of the filter.

The products

These filters are strongly characterised by a high grade of permeability (2.5 times as much as any other filter), an extremely fine and homogeneous microporosity and a retention capacity (filtration power) that is twice as high as that of filter boards or filters with the same weight. These sheets give an extremely high quality filtrate at a low cost, compared to any other filter with an equivalent weight thanks to their particular conformation created by their manufacturing on cylinders.

The DKF filter sheets have a micro-porous structure and a smooth, compact appearance that distinguishes them from the other boards that, instead, have a totally different appearance.

Fibres and mineral charges are finely dispersed in a strongly diluted aqueous suspension, which is filtered on rotating manufacturing cylinders: through the machine wire, the water gradually creates a fibrous panel of particles with different grades of fineness and particle sizes on the cylinder cladding . The flow is not forced: this makes a specific control and a high reproducibility of the pore size possible.

DKF is a new type of filter sheet. Its formulation, forming and manufacturing process is totally different from that of all other sheets presently existing on the market. Their micro-porous three-dimensional sieving structure has a void rate of 70% to 85% of its total volume, in spite of its compact and even structure.

The filtration liquid is compelled to flow slowly through the myriad of extremely fine channels and its touch time with the filter (electrostatically charged with a highly positive Z potential) is sufficient to depurate it from particles, microorganisms and colloids.

The homogeneous pore distribution causes its exhaustion index to be far superior to that of the other sheets on the market.


  • OV 80 (ST)
  • OV 110 (ST)
  • OV 160 (ST)
  • SO 45D (ST)
  • SO 60D (ST)
  • SO 80D (ST)
  • SO 100D (ST)
  • DKF 0 (ST)
  • DKF 00 (ST)
  • DKF 3 (ST)
  • DKF 4 (ST)
  • DKF 5 (ST)
  • DKF 7 (ST)
  • DKF 9 (ST)
  • DKF 15 (ST)
  • DKF 20 (ST)
  • DKF 30 (ST)
  • DKF W (ST)
  • DKF AC(ST)