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This is the generic term for particles or droplets that are finely distributed in the so-called dispersion medium. Water can be such a dispersion medium, but also other liquids. So can various solids or gases. The size of the individual particles is in the nano or micrometre range. One speaks of "Brownian motion" when they are mobile, e.g. in a liquid medium.

There are two basic types of colloids:

1. dispersion colloids: in them, a solid, liquid or gaseous substance is finely dispersed in a solid, liquid or gaseous dispersion medium. Without additional stabilisation, such systems are thermodynamically unstable.

2. molecular colloids: they consist of 103 - 109 atoms and are only colloidally soluble.

More details (source: "Magazin für Oberflächentechnik"):
The stability of colloidal solutions is strongly dependent on the (same-sense) charge of the individual particles. If this is neutralised by adding oppositely charged ions, the individual particles come together to form macroscopic aggregates, they coagulate (flocculation). The resulting precipitates can often be returned to colloidal form (peptisation). In many cases, they become oppositely charged by an excess of the precipitant and then dissolve again. Colloids are present in many biological and chemical systems (milk, medicines, blood, protein, glue, soap, varnish, lubricants).

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WIOTEC® Ense GmbH & Co. KG
Auf den Geeren 9-11
59469 Ense-Höingen, Germany

WIOTEC® Arnsberg GmbH & Co. KG
Wagenbergstraße 55
59759 Arnsberg, Germany

+49 2938 97833-0
+49 2938 97833-20

From metal to precious metal
The company WIOTEC® is your specialist for surface finishing and metalworking. In our electroplating shop, which is managed according to the latest environmental standards, we are capable of finishing both small parts and long parts of up to six meters. This makes us one of the leading and most efficient decorative surface coaters in Europe.

Our most important resource is our employees - with their commitment, competence and experience. Together with them, we work out and develop individual and tailor-made solutions for our customers. From detailed consultation and planning to purchasing, mechanical and chemical pre-treatment, professional electroplating and supplementary services - WIOTEC®'s range of services leaves nothing to be desired.



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