Several drying methods for water-based coatings.

Different drying methods have obvious differences in the drying speed and film quality of water-based coatings,
below on the various drying methods of water-based coatings.
1, natural drying
natural drying has the advantages of simple methods and universal application, but at the same time has the defect of slow drying speed. Under natural conditions, temperature and humidity and wind speed vary from time to time, and the drying speed and film quality are unstable

. If the high temperature, high humidity or humidity than the situation, the coating is prone to whitening, slow drying speed. At low temperatures, the drying rate is slow, especially at 5 degrees C, water-based coatings are difficult to film. These are important reasons to limit the application of water-based coatings.
2, hot air drying
hot air drying is the use of conflow principle, the temperature of 40 to 60 degrees C of hot air as the carrier, the heat energy transmitted to the surface of the workware coating, the coating absorbs energy after curing into a membrane heating and drying method. Electricity or steam is commonly used as a heat source to heat the air first, and heat is transmitted by conflowing heat from the hot air to the coating surface, allowing the coating to dry quickly. The use of hot air drying process, can significantly speed up the drying speed of the coating, and has a strong compliance characteristics, is a more common application of drying methods.
3, microwave drying
microwave refers to the wavelength of 1mm-1m, frequency of 300MHz-300GHz, penetrating electromagnetic waves, the commonly used microwave frequency of 915-2450MHz. Microwave heating is the principle of medium loss, and the dielectric constant of water is much larger than that of dry matter, and the great part of the energy released by electromagnetic field is absorbed by the moisture in the coating. Microwave field at a high speed of hundreds of millions of times per second periodically change the direction of the plus electric field, so that the water molecules swing rapidly, producing a significant thermal effect, so that the temperature inside and outside the coating at the same time rapidly increased. The advantages of microwave heating are that the drying speed is particularly fast, different substances have selective absorption of microwaves, there is no form request for the dried object, the heating of the coating film is very average, there is no temperature gradient, can dry the thick film.
4, UV
water-based UV wood coating, can use UV-cured drying. The so-called UV curing refers to the water-based UV wood coating in the wavelength of 300-400nm ultraviolet light to stop curing drying.
in the water-based UV coating contains a small amount of photosensitive agent, in the light of ultraviolet light, photosensitive agent absorbs a specific wavelength of ultraviolet light, synthesis produces an active group, triggering the polymerization of film-forming substances, forming a mesh structure and making the coating cured. Ultraviolet curing has the characteristics of fast coating curing speed and good coating quality. But. This method can only be used to dry water-based UV coatings, and can only be dried into flat-panel furniture coating plate.
5, infrared drying
infrared curing can be used to dry water-based wood coating coating. The so-called infrared curing practice refers to the coated furniture plate and its coating in the infrared light, absorbing radiant energy and converted into thermal energy, thus completing the curing of the coating. Infrared is an invisible ray between visible light and microwaves with a wavelength of 0.72-1000um. According to the wavelength range, can be divided into "near", "medium" and "far" infrared, commonly used far-infrared drying coating infrared curing has the advantages of fast curing speed, heating speed, good curing quality, but when using infrared heating drying coating, the coating has a clear temperature gradient, its drying is extended from the outside to the inside, which makes it not suitable for drying thick coating film;
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