Before making a stencil, the mesh should be degreased with a suitable degreasing agent, unless it has a special surface treatment like e.g. SEFAR PET 1500.
Please do not use household detergents!

Deionized water

Water that goes through an ion exchange process in which all positive and negative ions are removed.


The mass in grams of 9000 m of fiber or yarn.
A direct yarn numbering system to define size of fiber or yarn. The higher the number, the coarser (larger) the yarn.

Depth filter

A filter medium consisting of randomly distributed particles or fibers resulting in openings having a non-uniform and tortuous path.

Differential pressure

The difference in pressure between two points of a system, such as between two sides of an orifice.

Direct emulsion

UV - sensitive Emulsion layer for screen printing stencils

Double layer fabric

By combining a fine filter layer and an open, coarser mesh layer, these fabrics combine high flow capacity and fine particle capture efficiency with the extremely durable construction needed for large-scale process filtration.

Downstream side

The side of a product stream that has already passed through a given filter system; portion located after the filtration unit.

Dual chamber test method

Measures near-field shielding
effectiveness by indicating the signal attenuation caused by passage through a test material.

Dutch weave

Warp and weft wire diameters are different in size: the weft wires are closer together, thus providing excellent strength and high density.


The process of adding color to textiles in fiber, yarn or fabric form.

Effective area

The total area of the porous medium exposed to flow in a filter element.


The ability, expressed as a percentage, of a filter to remove a specified artificial contaminant at a given contaminant concentration under specified test conditions.


A toxin produced by bacteria. The toxin is present in the environment only after the death of the bacteria.


A toxin produced by bacteria. The toxin is present in the environment only after the death of the bacteria.


Exposing the photosensitive layer (emulsion) to UV light. The uncovered areas will harden and become water insoluble. The unexposed areas remain water soluble and can be washed out with water.

Exposure time

Time, the stencil is exposed to UV emission.


Substances that can be leached from a filter during the filtration process or under other specified conditions.

Fabric geometry

See mesh geometry

Farady cage

A cage made of conductive material. Static fields and discharges do not pass through it. Electromagnetic energy passing through the skin or shield is attenuated to varying degrees.

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9410 Heiden

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Fax +41 71 898 5721

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Filtration & Separation

Screen Printing