Pages: 5 Published: Jan 2012
ALTHOUGH THE FIRST POWDER COATING WAS developed in the late 1950s, it was not until the early 1970s that governmental regulations and the “80 % solids rule” brought about what was termed the “powder explosion.” Requirements indicated that liquid coatings were to have markedly decreased volatile organic content, and this provided the impetus for companies to look into new coating technologies—powder coating, radiation cure, and high solids. It was a difficult task for entrenched companies to change and product manufacturing, equipment costs, and lethargy slowed progress. Solvents were inexpensive and it was easy to apply low-solids, solvent-based coatings. But, a number of old and newly established companies continued with development of the new systems, and today these three new technologies have a strong position in the coatings industry. Numerous industrial, consumer, and automotive finishes, for a broad range of products, are applied with powder coating technology. Powder coating has grown over the past few decades, and today it is a widely used technology that has captured about 12–15 % of the finishing market. Powder coatings are dry, effectively 100 % solids materials that are supplied as free-flowing powders. The final coatings are either thermoplastic or thermoset in character. They differ from conventional coating systems in that a solvent is not needed to keep the polymeric binder, pigment and/or filler, and additives in a combined state for application and film formation. They are mainly applied by a thermal (fluid bed) method, an electrostatic (spray) method, or a combination of thermal and electrostatic methods. After application, the powder is heated and the particles melt and flow to form a hard protective and/or decorative coating for a wide variety of consumer and industrial end uses. Although powder coatings provide very high quality finishes for metal, plastic, and wood substrates, they have other important advantages in today's marketplace. These advantages are often described within the industry as the Five E's, and they should be kept in mind when contemplating the use of powder coatings: • Economy • Efficiency • Energy savings • Environmental compliance • Excellence of finish.
Paper ID: MNL12259M
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