How are bicycles painted? Durable paintwork with powder coating
Durability, versatility and environmental friendliness – the strengths of powder coating. Teknos, a coatings company, produces ten million kilos of completely solvent-free powder coatings annually. These coatings are used to coat many familiar everyday objects.
Washing machine, microwave oven, refrigerator, water and electric heaters, bicycles, car wheels. Many familiar household appliances and objects have been coated with powder coating.
As its name indicates, powder coating is a fine powder and has the consistency of wheat flour rather than that of paint spread with a brush. Powder coating is usually used in surface coating of various metals. But how is powder coating actually used?
– The surface being coated is first sprayed with electrostatically charged powder, after which it is transferred into an oven to be baked at 160–200 degrees Celsius. The powder melts in the oven and creates a solid and smooth paint surface, explains Harry Kouri, Sales Director at Teknos.
Teknos produces approximately ten million kilograms of powder coatings every year. Products such as Genelec speakers and Jopo bicycles are coated using Teknos powder coatings. Powder coating is mainly sold to industry and paint shops, but over the last few years powder coatings have also become available to consumers.
Similarly, to traditional liquid coatings, powder coating consists of a binder, a hardener, pigments, fillers, and additives that in a chemical process have been ground into a homogeneous powder. Coating additives are selected according to their purpose.
– Powder coatings with antimicrobial and antibacterial properties can be used on surfaces in facilities such as hospitals, kitchens, and kindergartens, says Kouri.
Durability and environmental friendliness are two major assets
In his own daily life, Kouri works with powder coatings and is a little more observant of different surfaces than the average consumer.
– Checking out painted surfaces is, admittedly, a little bit of an occupational hazard. For example, in a hardware shop I might first notice the paint on a tool before paying attention to the tool's functional qualities. Powder coating is a great way to provide consumers with products that are wear resistant.
In addition to being highly hard-wearing and having excellent impact and weather resistance, powder coating is also a more environmentally friendly option.
– Powder coatings are completely solvent-free and do not contain any volatile organic compounds (VOCs), which are dangerous to human health and cause harm to the environment, Kouri says.
Applying powder coating by electrostatic spraying is very efficient, and only a small amount of the powder is wasted. Additionally, any powder that missed its target can be collected for reuse and powder coating waste can be burned for energy.
Development of more environmentally friendly coatings is underway in our laboratory
Powder coating has been used for industrial purposes since the 1960s. Kouri says that the use of powder coating has increased steadily over the years.– Originally, powder coatings became popular as a wear resistant, fast, and cost-efficient alternative, but today, environmental values have become increasingly important.
Environmental values are important to Kouri, too. He is watching with keen interest what type of new and even more eco-friendly products the chemists at Teknos' laboratory come up with.
As its sustainable development goal, Teknos aims to, among other things, reduce the VOC concentration of its products by approximately 5% every year.
– Another one of our goals is to increase the share of water-borne products especially in business to consumer and in professional trade. This will enable us to reduce emissions of VOCs, i.e., volatile organic compounds, says Kouri.
Originally published for Finnish campaign by Kemianteollisuus ry arjenympyrat.fi