Properties of Cured Powder Coating
After the powder is coated on metal, it is cured and then, takes its final form. The material taken out of the curing oven is expected to have the following properties and these properties reflect the quality of the product.
The coated surface should contain no dirt, dust particles, or overcured powder particles. Clarity and uniformity should be visible on the surfaces of singe-color coatings. If the surface has different colored spots or parts, this indicates that the production quality of the powder is low. Such a situation ruins the aesthetic appearance,which is one of the main purposes of coating.
The color of the paint should match the user’s reference color. The matter of color in powder coating is very critical compared to other coating types. The color must match exactly. Companies that produce powders carry out color studies in their laboratories and usually achieve the result by using the LAB Color System. While a color comparison can be made using any colorimeter, the eyes are the final decision makers. This is because they are the most sensitive colorimeters. There are various systems in which color is standardized. RAL is the most famous and frequently used one of these systems. RAL is a German company that has classified colors according to their shades and brightness. Color shades are divided as 1.Yellow, 2.Orange, 3.Red, 4.Purple, 5.Blue, 6.Green, 7.Gray, 8.Brown, 9.White, Black, Metallic Gray. There are also 2 different series: matte and glossy.
Another remarkable feature of powder coating is its gloss. Gloss is defined by a unit called “gloss”. Gloss is determined by comparing a glossmeter or eyes with any reference. Its value ranges between 0 (zero) and 100 (one hundred). 0 (zero) means the most matte, 100 (one hundred) means the glossiest. The values between them are called semi-glossy and/or semi-matte.
A wide variety of surface appearances can be obtained with powder coating. The most common are, of course, flat surfaces. Other types of surfaces include wrinkle (less rough), forged (very rough, single color grain, double color, requiring and not requiring a varnish layer), textured (sandpaper appearance), metallic (shiny, requiring or not requiring varnish), varnished (pure or colored), and fluorescent surfaces. Moreover, as a result of recent developments, salt and pepper (chipboard appearance, various colors), silky, spider-web appearance surfaces have been introduced to the market.