There are electrostatic charges everywhere in our daily life. We know them for example from the situation that our hair strick out of the head when taking off a woolen pullover.
ESD is the abbreviation of "electro static discharge" and is evoked through exchange of charges between two bodies with different potential of tensions. Electrostatic charges emerge through friction or separation of two different materials.
- Walking across synthetic floors
- Friction on synthetic clothes
- Displacing of plastic containers
- Unwinding of PVC-tapes
- Moving of conveyer bands
Static charges can lead to high tensions in modern workplaces - more than 10.000V are not unusual. At an air moisture below 20% even 30.000V have been measured.
Nevertheless, what often expresses itself in small sparks also affects or harms electrical devices such as in micro electronics. Electronic components possess a sensitivity for ESD already at 30-100V and can therefore be massively harmed through electrostatic discharges.
In explosion-prone areas electrostatic discharges can evoke devastating effects such as dust explosions or the inflammation of highly combustible fluids.
These critical charges can be prevented with the help of conductive fibres or yarns in textiles as they work electrostatically deducing. Permanant outcomes are achieved if conductive fibres are included in the textile already in spinning or weaving the textile.
Conductive materials possess low resistance (lower than 105 Ohm) and therefore cater for fast running off. As soon as the conductive material is grounded the whole charge runs off. In case of dissipative materials surface resistance is between 105 Ω and 1012 Ω. They are compensating differences in potentials in a relatively short period of time. Isolating materials possess surface resistance of minimum 1012 Ω and are quite complex to ground. Static charges rest at one place of these materials for long and do not run off. This feature provides danger and has to be controlled as part of an ESD-program.
Depending on the combination of metallized fibres the desired level of protection can be achieved for the respective area of application.