The new "Environmental Protection Law" of the country was promulgated and implemented, and the "strictest in history" new environmental protection law struck. With the improvement of people's awareness of environmental protection, the trend of water-based coating is becoming more and more obvious. Water-based paint products have gradually matured and began to enter the public's vision of decoration. The environmental protection characteristics of water-based paint are undoubted, but there are certain limitations in the construction process. It is a breeze to master the correct methods to overcome these problems.
Limitation 1: Dilution of water-based wood paint
In normal seasons, the storage and use of water-based paint will not have too many problems. The winter temperature is low, and water-based paint can no longer be directly mixed with tap water, because the water temperature is very low, it will affect the drying speed of water-based paint, and even cause the phenomenon of not drying . The winter water-based paint can be diluted in the following two ways:
1. Dilute with warm water at 40-50 degrees. Diluted with warm water, the water evaporates faster, which can increase the drying speed of water-based paint. While diluting with warm water, warm water can also be used to keep the water-based paints warm-that is, the adjusted water-based paints can be kept warm in a warm water basin, especially for colored paints.
2. Mix and dilute with alcohol and warm water. The ratio of alcohol and water is recommended to be 1:1, this method is good for primer. But don't take this method when you finish the top coat for the last time, it will affect the leveling and cause a bad feel or orange peel.
Limitation 2: High construction environment requirements
Humidity is a key factor affecting the construction of water-based paints. The humidity is too low, drying is too fast, affecting the leveling, high humidity, slow drying, easy to whitish; generally suitable humidity is 40-80%.
Limitation 3: Low temperature construction is difficult
Water-based paint can not be applied thickly at one time, it should be scraped many times, otherwise it is easy to crack. When the colored transparent paint is applied at low temperature, uneven color distribution will occur.
During the construction, the alcohol and the color must be adjusted first, then add the clear coat and then add 40 degrees warm water to debug the construction, so that the operation will make the color and dispersion more uniform.
Construction method of wood paint
1. Before painting, paint furniture, etc. should be degreased and decontaminated, and polished and leveled.
2. Use matching water-based primer, the primer is prepared according to the product description ratio, stir evenly, then dilute with water to the construction viscosity according to the situation, filter with silk cloth, and let it stand for 20 minutes to mature before construction. The first coat of primer should be applied thinly and evenly. After drying for 3 to 4 hours (25°C, 50% humidity), sand it with sandpaper.
3. Depending on the depth of the wood grain, the putty is better to be scraped thinly. When the putty is scraped, it should be scraped into the wooden seam. After the putty is dried, sand it thoroughly with sandpaper.
4. Brush the putty or the first primer with another primer 1 or 2 times. After the primer has dried, sand it with sandpaper to make the substrate delicate and smooth.
5. The topcoat is prepared according to the product description ratio. After mixing the main paint with the curing agent, it is stirred intermittently for 10 minutes, then diluted with water to the construction viscosity according to the situation, filtered with silk cloth, and allowed to be applied after 20 minutes of curing. The topcoat is generally applied 1 to 2 times. If higher fullness is required, the number of topcoat applications can be increased. The overcoating time is within 2 to 16 hours (25°C, 50% humidity). There is no need to polish, if the overcoating time exceeds 16 hours, the topcoat should be applied after polishing. Before the last coat of paint is applied, after the paint film is sufficiently dry (approximately 12 hours), lightly dry or wet the unevenness with 1000-mesh sandpaper and wipe it clean, and then brush or spray the last coat of paint.
Precautions for wood paint construction
1. The wood paint should be painted after the ground construction is completed, and the construction should be ventilated and free of dust to avoid affecting the overall effect. The wood paint and the latex paint cannot be applied at the same time.
2. The wood should be dry, the moisture content should not exceed 15%, and the humidity and temperature of the construction environment should not be too high.
3. Most of the paint products are composed of three components (main paint, thinner, curing agent), stir evenly before mixing, and strictly match the paint in proportion.
4. Choose the supporting thinner and curing agent to avoid bottom biting and wrinkling.
5. After the preparation, it should be filtered, and it can be painted for 10 to 15 minutes at rest.
6. After placing the prepared paint for a period of time, an appropriate amount of thinner can be added to prevent the viscosity from increasing and producing brush marks.
7. The finished paint should be used up within 4 hours, and it should not be poured back to the original paint bucket if it is not used up.
8. The construction area should not exceed 4-5 boards wide at a time to avoid brush marks.
9. The coating film should not be too thick in one application. You must wait for the coating film to dry before proceeding to the next layer of construction.
10. The primer should not be applied thick, just a thin layer. The top coat should not be applied too thick at one time, otherwise it will affect the drying speed and hardness.
11. The wood paint must be thoroughly polished before construction, until the entire paint film is smooth and smooth to the touch, to avoid poor adhesion between the layers, resulting in a layer.
12. Grinding must be done after hard work, otherwise there will be fog or whitening.
13. The construction cannot be carried out when the ambient temperature is lower than 7°C or the humidity is higher than 85%, otherwise it will be prone to the defects such as whitening of paint film.