What is powder coating
time2023/01/02
- In this short article, you can learn what is the electrostatic powder coating and how to make powder coating on metal surface finishing.
What is powder coating
The working principle of electrostatic powder spraying method is almost the same as that of the general electrostatic spraying method of liquid paint. The difference is that the powder spraying is dispersed rather than atomized. It is a coating sprayed by an electrostatic powder spray gun, which makes the powder particles negatively charged while dispersing. The charged powder particles are applied to the grounded coating by the action of air flow (or centrifugal force and other forces) and electrostatic attraction, and then heated to melt and solidify to form a film. Electrostatic powder coating is a powder coating method that plays a leading role in the industrial coating field
1. Environmental protection
With the increasingly strict regulation of the environmental protection law on the content of organic volatile matter (voc) in the atmosphere, the coating industry has been trying to develop a coating technology that is milder to the environment. After long-term research and experiments, it is found that "electrostatic powder spraying" is the cleanest coating technology that can be achieved at present.
Powder coatings do not use volatile solvents such as organic solvents and water, but are inorganic solvent based coatings, which greatly reduces the pollution caused by solvents, including poisoning events caused by operators due to the presence of organic solvents; It will not cause fire due to organic solvent. Since the appearance of powder coatings, there has been no major safety accident caused by powder coatings.
Powder coating is a kind of coating with pure solid composition, which can be completely sprayed automatically. Large amount or super sprayed powder can be easily collected by the recycling system to achieve the purpose of recycling. Therefore, the utilization rate of powder coatings can reach almost 100%, which enables the coating industry to reduce the cost of waste disposal and minimize the degree of environmental pollution
2. Save cost
Among the components formed in the film, the solvent type is about 60%~65%, while the powder coating can achieve almost 100% efficiency, and the powder not attached to the sprayed object can be recycled. In general, the use of powder spraying technology can make the painting operation as economical and effective as possible. In powder coating operation, if there is any part with poor coating, it can be blown off with an air gun before baking, and then coated again. Therefore, it can avoid surface paint flow, paint dripping and other phenomena, greatly reducing the probability of repainting rework. Because electrostatic spraying is used for powder spraying, the coating equipment can be almost fully automated, saving human resources. Even if manual assistance is required, the coating personnel can master the operation skills without long-term training. Powder coating is 100% solid composition, so no solvent is added, so the amount of coating is reduced, packaging is saved, and storage space is reduced
3. Save energy
The powder coating has no organic volatile matter, which avoids the waste caused by volatilization to the atmosphere. Therefore, compared with the liquid coating, the energy cost is greatly reduced. The electrostatic spraying equipment can get thick film by spraying once, without repeated spraying or priming paint, which is faster and more efficient than the painting with the same film thickness. The painting equipment does not need static time, which can save equipment space. In addition, the baking time of powder coating is also shorter than that of liquid coating, which can greatly reduce the fuel energy consumption, shorten the coating line, and improve the output and production efficiency
4. Excellent film performance
As long as the powder coating is directly sprayed on the surface of the pretreated MDF sheet, and then baked, the film surface with excellent performance can be obtained. General powder coatings have lasting properties, including abrasion resistance, impact resistance, adhesion, toughness, corrosion resistance and chemical resistance. In addition to the above advantages, powder coatings for outdoor use also include high weather resistance and pollution resistance. High thickness film can be obtained by one spraying of powder coating, and the film thickness can be 50-300 μ M, and there is no dripping or stagnation of solvent coating during thick coating