History and Explanation of the Electrostatic Painting Process
The first U.S. patent for the electrostatic painting process was awarded to Harold Ransburg in the late 1940’s. Electrostatic spray painting was an immediate success as manufacturers quickly perceived the substantial materials savings that could be achieved. With the addition of manufacturing and research operations in Europe and Japan, Ransburg expanded on a global level over the next 20 years. The steady growth was complemented by an increasing reputation for innovative and effective technology.
Electrostatic coating is a manufacturing process that employs charged particles to more efficiently paint a workpiece. Paint, in the form of either powdered particles or atomized liquid, is initially projected towards a conductive workpiece using normal spraying methods, and is then accelerated toward the workpiece by a powerful electrostatic charge.
After the charging is finished, and the setup is done, the painting can take place. The paint with a positive charge is sprayed onto the metal object and grabs on easily to the metal’s surface. The attraction from the opposing charges is so strong that even if just one side of a metal pole is sprayed, the charge will automatically draw the paint around the metal, covering its entire surface.
Process Characteristics
- Uses a high voltage electrostatic charge which is applied to both the workpiece and the sprayer mechanism
- Is incredibly efficient, using 95% of sprayed paint due to reduced over-spray and better wrap-around
- Paint materials can be either powdered or liquid
- Workpieces must be conductive
The paint also generally proves to be more durable than other liquid paints plus. In addition, the process is an eco-friendly process since it does not use any solvents that can evaporate or contaminate drainage water.