Electrostatics have been known for many decades, and are used in a variety of industrial processes. In fact, electrostatics are essential for all of life to exist, too. This is because of hydrogen bonding – a critical process for holding the strands of DNA in everyone to stick together – relies on natural electrostatic interactions to occur. In some advanced biogenetic techniques, electrostatics can be manipulated at the sub-cellular level. However, for most industrial applications, electrostatics are used in ways which don't require this degree of biological accuracy. Read on to discover some of the common ways in which electrostatics are used in both industrial processes and consumer products.
Most photocopiers use an electrostatically charged imaging drum to produce copies of what they have scanned. Some laser printers also make use of this technology, known in the industry as xerography. The drum used in printers and copiers is electrically charged in certain areas that correspond to the dark parts of the image that is to be created. A negative charge is applied elsewhere. When toner, a fine powder, is poured over the drum, it matches the electrostatic image on the drum. After this, a paper is passed around the drum and heated so that the toner sticks to the paper and is fixed in place. The paper is then passed on through the system. Crucially, the electrostatic charge that has been applied to the drum is dropped, allowing for an entirely new image to be generated.
Affording a very high-quality finish, powder coating is a method of covering items with a paint-like covering that is hard-wearing and even in appearance. When the powder is sprayed onto a workpiece, it is electrostatically charged, which means that it will cling on in a very strong fashion. Unlike wet spray painting, this means that a very regular finish can be obtained without the need to keep passing the spray gun back and forth many times. Powder coated products come in a huge variety of forms and are particularly effective with things that will be used outside, such as architectural columns, street furniture and vehicles.
Van de Graff Generators
Electrostatics lie at the heart of Van de Graff machines, which separate charges and generate potential differences in the range of volts being used. Silk is used to create a flexible belt which literally transports the charged ions from positive to negative. Many are used to demonstrate charge leakage through a sphere which can be touched, creating an attractive corona discharge.