Coating knowledge: how to improve the adhesion of waterborne wood paint film

Core tip: China is a big country of furniture production, which needs to consume a lot of wood paint every year, and the use is increasing year by year At present, a large number of solvent based wood coatings are used in China, such as polyurethane (PU) wood coatings, which will release a large amount of VOC and seriously harm the health of consumers and the ecological environment With the limited use of solvent based wood coatings in various countries, water-based coatings are increasingly recognized by the society and widely used in various furniture coatings Waterborne coating is the best coating to reduce VOC, and it is a feasible measure to solve the environmental pollution problem of furniture finishing fundamentally Water based wood coatings replace organic solution with water Paint agent, top 10 Chinese wall paint brands Recommended introduction: interior wall paint and exterior wall paint can achieve beautiful, clean and pleasant effects, but the effects in different environments are different, so the color of the paint will be different There are ten brands of Chinese paint, ten brands of global paint, ten brands of Chinese wall paint, and ten brands of Chinese paint, Famous trademark of Chinese paint and coating In private rooms, most of us choose according to our own personality, personal hobbies and living habits The younger generation will choose the interior wall paint with rich colors and bright colors, while the older ones will have some working experience Paint Home News: China is a big country of furniture production, which needs to consume a lot of wood paint every year, and the amount of use is increasing year by year At present, a large number of solvent based wood coatings are used in China, such as polyurethane (PU) wood coatings, which will release a large amount of VOC and seriously harm the health of consumers and the ecological environment With the limited use of solvent based wood coatings in various countries, water-based coatings are increasingly recognized by the society and widely used in various furniture coatings Waterborne coating is the best coating to reduce VOC, and it is a feasible measure to solve the environmental pollution problem of furniture finishing fundamentally Water based wood coatings use water instead of organic solvent as the dispersing medium, which greatly reduces the harm of organic solvent volatilization to the atmosphere and human body At present, waterborne wood coatings have become the best-selling products in Europe, America and other countries, and are quietly rising in China, starting to have a small number of varieties on the market Only after coating film, can the paint realize its use value as a commodity The quality of paint film is very important to the surface quality of high-end furniture, which determines the competitiveness of furniture market to a large extent Adhesion refers to the firmness of the paint film and the surface of the coated material through physical and chemical actions The size of adhesion determines the quality of paint film to a large extent, and the amount of coating affects the size of adhesion Therefore, it is necessary to improve the coating technology of water-based paint film adhesion for furniture We can know the adhesion of water-based paint through a test Take a piece of hard maple veneer furniture panel, sand along the direction of wood grain, and spray two coats of water-based sealing primer, two coats of primer and two coats of finish paint according to the specified coating amount After 7 days storage in a constant temperature and humidity room with 25 ℃ and 77% relative humidity, the adhesion of the paint film was tested by pig Under the microscope, the peeling off of the paint film in the cutting grid was observed, and the number of peeling grids at the intersection of the cutting marks was counted The adhesion of the paint film is evaluated by the percentage of the number of peeled grids in the total cut grids The peeling rate of paint film at the intersection of cut marks is taken as the index to evaluate the adhesion The larger the peeling rate is, the worse the adhesion is; the smaller the peeling rate is, the better the adhesion is As for the adhesion of the paint film, generally speaking, the larger the coating amount, the thicker the paint film, the smaller the adhesion The coating amount and thickness of each layer are different For the whole film, the adhesion will be different with different structure For the same object painted in the same way, the adhesion of different areas is different, which is mainly caused by uneven coating, uneven roughness and the specific structure of wood The adhesion decreases with the increase of the coating amount of sealer, primer and topcoat This is because the waterborne styrene acrylic sealing primer is a one-component coating, and film-forming and curing belong to physical change When the paint is sprayed on the blank, the sealing primer directly contacts with the wood, and the paint film forms a series of "paint nails" in the conduit or other small grooves on the blank surface To a great extent, the adhesive force determines the degree of penetration of the paint into the substrate surface and the number of "paint nails" formed When the surface roughness of the blank is certain, if the coating amount is too small, the coating and the base material cannot form enough "paint nails", the adhesion will be reduced; when the coating amount is too large, part of the coating cannot penetrate into the capillary pore structure of the wood and accumulate on the blank surface, the adhesion will also be reduced In order to obtain better film adhesion, the reasonable coating amount is 80g / m2 for the sealing primer, 120g / m2 for the primer and 100g / m2 for the top coat Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,