The earliest forms of powder coating have been around since the early 1950s and were born from America’s insatiable appetite for motor vehicles. The continued streamlining of the sub-contract supplier network led to manufacturers seeking the “holy grail” of a one coat finishing system. This, coupled with early signs from environmental pressure groups, led to powder coating as we know it today, which can be best described as “solid paint”.
The advantages over the established systems of traditional spray enamelling were speed of application and the continued pursuit of a high performance coating process. In place of the traditional etch prime, primer and possibly two coats of top coat, powder coating can do these all in one operation, though there were limitations.
Some of earliest examples of plastic or powder coating were quite simply of placing the pre-heated component in vat of aerated or fluidised powder. The powder was placed in a container on top of a fine membrane then a controlled amount of compressed air was passed through the membrane. The powder then bubbled and subsequently doubled in volume and the heated components were placed in this bubbling fluid for the time determined by the thickness of finish required and the amount of sink the component held. This was powder coating in most simple form and offered little or no performance or aesthetic qualities but it did offer the distinct advantage of speed and, in turn, cost savings. Read the rest of this entry »
