Allowing paints to harden and dry
Actually, this happens entirely by itself. Every one and two-component spray paint (in the case of 2K spray paint, this is dependent on the hardener being properly mixed with the paint according to the instructions) will become dry at some point, without the need for you to do anything. Either the solvents evaporate from the one-component paint, or the chemical reaction in 2K paint has taken place. Both lead to the positive characteristics that painted surfaces demonstrate: protection, shine and a superior look. Despite the uncomplicated drying process, there are however a few things you need to bear in mind in order to achieve best results.
2K dries differently to 1K
2K paint: The second component triggers a chemical reaction with the actual paint, which results in the paint joining with the hardener. This results in the creation of extremely hard-wearing surfaces that have the various properties typical of two-component paints: these include solvent resistance, the best adhesion properties and an intensive sheen. With one-component acrylic and NC paints, physical drying occurs on the basis of the solvent evaporating. With synthetic resin paints, oxidative drying occurs, due to the reaction with oxygen. As a rule, this takes longer than physical drying.
With all variants, heat can speed up the drying process. But in orderto avoid blistering, the temperature must not be too hot immediately after application of the paint. These small bubbles, which occasionally burst, are a result of, for example, direct solar radiation during summer temperature conditions. Or alternatively, from using infrared radiators if the flash time was not observed before heat drying commenced. The ideal air temperature is 20°C–25°C. A further important factor is the air humidity, which should be in the range of 45–60% relative humidity. It is also important that the surrounding air is free of impurities. Dust, pollination, small insects – it seems that freshly applied paint is like a magnet to the tiny microparticles found in the air. As far as possible, use a separate, well-ventilated room for painting, or replace the filters in the paint booth regularly. A further aspect is adhering to drying times. Only once the paint has completely hardened are all the desired properties present. If paint is not completely dry, adhesion and resistance to solvents and moisture are not completely in place, even though the surface may feel dry to the touch. The main thing is not the annoying spot of colour on the end of your finger, which you got from paint that was supposedly dry. It’s more about the quality of the paintwork. In the field of professional painting, it’s a question of process costs, and ultimately, contented customers.