As an environmentally friendly coating, water-based paint plays an increasingly important role in the modern coating process. Its coating process and process control directly determine the quality of coating. Among them, 70% of the coating defects are caused by unqualified pre-treatment of painting. Therefore, when using water-based paint, we must pay attention to the following points to ensure the stability and reliability of the coating quality.
First, do a good job of substrate pretreatment
Substrate pretreatment is a key step in the coating process, the purpose of which is to remove oil, rust, oxide scale, dust and other impurities on the surface of the substrate to ensure the adhesion and anti-corrosion performance between the coating and the substrate. The specific method of substrate preparation varies depending on the requirements of the workpiece, but usually includes steps such as degreasing, rust removal, and dust removal. For zinc-rich products, it is also necessary to increase the roughness to improve the adhesion of the coating to the substrate. When pre-treating the substrate, it is necessary to ensure that the surface of the coated object is free of oil, rust, oxide scale, dust and other attachments to ensure the quality and durability of the coating.
2. Master temperature and humidity
The environmental conditions of the construction site also have an important impact on the quality of the coating. Temperature and humidity are one of the key factors affecting the quality of the coating. During construction, it is necessary to pay attention to ventilation conditions and control temperature and humidity. Generally speaking, the temperature during construction is best between 5-35 and the relative humidity of the air should be less than 80%. In addition, the temperature of the substrate should also be higher than the ** temperature3 to avoid quality problems such as whitening and blistering of the coating.
3. Pay attention to the use of paint
The proportion and matching of paint is also an important factor affecting the quality of coating. Different products have different proportioning requirements, and the construction personnel must carefully implement them in accordance with the product manual. When applying the composite coating, each brush should be carried out after the lower layer is dry, and the drying standard is acupressure drying or drying to ensure the adhesion and anti-corrosion performance between the coatings. Two-component or three-component paints must be stirred evenly after blending and cured for 15 minutes to ensure that the main paint and the curing agent are fully mixed and eliminate the stirring bubbles generated inside. If necessary, the paint should also be filtered before use. In addition, the paint must be used up within the specified time after the paint ratio is good to avoid paint deterioration and affect the coating quality.
With the continuous progress of science and technology and the continuous improvement of the coating process, we believe that the coating process and process control of water-based paint will be more mature and advanced, injecting new vitality and impetus into the development of the coating industry.