In recent years, sand in water and water in water multi-color coating have become a new star of building exterior wall coating. They are more and more widely used, but there are many problems in the construction process. Today, follow the editor to learn: the advantages of multi-color coating, construction technology, problems encountered and solutions.
1、 Advantages of colorful coatings
1. Light and safe: the body is very light, about 1kg / ㎡, equivalent to 1 / 6 of the real stone paint, 1 / 40 of the dry hanging stone, and 1 / 20 of the face brick, without any hidden danger.
2. Fast construction: each person can operate about 120 ㎡ every day; the color is rich, and you can choose the color freely.
3. Low pollution: the multi-color paint is water-based, environmentally friendly, smooth and waterproof, and the dust will not penetrate and deposit.
4. Wide range of use: because it is a coating product, its use limitation is very small. Concrete, PC board, ALC board, asbestos board and some complex building parts can be selected as the base surface.
5. Cost: the cost is slightly higher than that of ordinary stone paint, far lower than that of stone dry hanging.
2、 Construction technology of multicolor coating
One
Environmental protection
1. Check the places to be protected before construction.
2. Make construction arrangement to cover the windowsill, door edge, trees and some places on the ground that may be contaminated with plastic film.
Two
Base inspection and treatment
1. Comprehensively check whether there are cracks and hollows on the base wall. Remove the hollowed, semi detached and loose base surface.
2. Clean the old wall, remove the old coating, floating ash, etc.
3. Use wire brush, sandpaper, etc. to remove dust, grease, etc.
4. If there is a lot of floating ash on the wall, the high-pressure water gun shall be used to wash the surface of the external wall.
5. Cracks and hollows shall be leveled with external wall putty and maintained for 5-7 days.
6. If the construction is carried out on the finished insulation board, the surface of the Board shall be smooth and free of burrs. If there are burrs, they shall be polished with sandpaper.
Three
Batching putty
1. Apply 1-2 times of flexible leveling putty on the treated base surface, each time of putty should not be too thick, for the purpose of wall leveling.
2. Ceramic tile and mosaic wall should be fully applied with interface agent first, and then the tile renovation putty should be fully applied and leveled again.
3. Polish the putty surface with water and remove the floating ash and burr on the surface.
4. The putty shall be cured for 15-20d (23 ± 2 ℃) after construction to make the moisture content of base course less than 10% and pH value less than 10.
5. Scrape the flexible smooth glue for 2-3 times in batches, with the construction interval of 12h (23 ± 2 ℃), and dry it for 24h (23 ± 2 ℃) after completion.
6. Polish the surface with fine water abrasive to make the surface smooth and provide a good base for coating construction.
Four
Brushing primer
1. Use the wool roller or spray gun to evenly apply the special closed emulsion 1-2 times.
2. After the primer is completely dried (6h / 23 ± 2 ℃), the next process can be carried out.
Five
Spraying colorful paint
1. Use special spray gun to evenly spray 1-2 times of colorful coating. (the water in water diameter is generally about 3.0, and the sand in water diameter is 3.5-4.0)
2. The interval of each construction is 12h (23 ± 2 ℃).
3. The paint is dried for 24h / 23 ± 2 ℃ after spraying.
Six
Spray finish
1. Apply 1-2 coats of varnish evenly with spray gun.
2. The interval of each pass is 4-6h / 23 ± 2 ℃.
Seven
Coating curing
The hardening period of the coating is 7d / 23 ± 2 ℃, during which no man-made damage is allowed.
Eight
Cleaning after construction of colorful coating
1. One day after the completion of the process, remove the protective covering film of relevant parts.
2. Clean relevant parts and ground.
Nine
Precautions for construction of multicolor coating
1. Do not stir the colorful paint.
2. Do not mix with other substances.
3. Do not dilute with water.
4. The paint after opening the tank shall be used up once as much as possible.
Note 1
Special putty shall be used for the base course, preferably gray putty mortar. Traditional white fine putty is not recommended. The gray putty, mainly composed of gray Portland cement and acrylic polymer, has good adhesion, filling (small shrinkage), cracking resistance and workability, certain strength and hardness, moderate drying time (surface dry and dry), easy to scratch and polish. It is obvious that the gray putty mortar has more advantages than the white putty in the construction of water in water multicolor coating. Putty polishing is also a key part. During the day, the special sand frame can be used to polish the putty one by one to make the height of the wall smooth and consistent. At night, the sun lamp can be used to check the divided wall surface, and the uneven parts can be polished continuously. If the parts are not polished well at that time, mark them with a marker pen, repair them with putty, and polish them again after drying out. Each part is required to be polished The flatness of the block is flat. The maintenance time of sprinkling water is about 24 hours, and the next construction can only be carried out after it is completely dry.
Note 2
When making litchi surface effect, before most manufacturers do not touch the water-in-water sand, the water-in-water multi-color coating needs to be painted with texture bone material as the base; when making the fire board effect, the water-in-water multi-color coating needs to be painted with color sand real stone paint as the base and then painted with color sand real stone paint, so the sensory effect is also obvious, but the texture or color sand real stone paint used will be exposed more or less outside, two kinds of materials It is mainly composed of crushed stone, the surface is concave and convex, and there are numerous fine holes on the product surface. Due to the phenomenon of air back sticking, dust and dirt will adhere to the wall surface and cause local pollution. Of course, the original appearance can be restored after the rain water is washed in the protection of the top coat. There are also those who prefer to use elastic intermediate coat as primer, and use special elastic intermediate coat to increase the thickness of its film to make the wall waterproof and crack resistant (the main purpose of this process is to increase the thickness of the film, increase the crack resistance and water resistance). It is recommended to use water and sand for texture effect. The process is simple and the effect is good! The effect of litchi surface texture can be realized by spraying water sand directly. The diamond chemical system is made of colorful raw materials, and the effect of water sand imitating stone is lifelike, which can adapt to the large-scale production.
Note 3: the primer must be applied in place, and the dead corner shall not be missed, especially the side, line and internal corner of waist line (when color jumping) of door and window opening. Otherwise, when the main material is sprayed, the protective film is pulled off or the masking paper is removed, the water in the water colorful coating at this part is easy to curl up, and then the stubble is easy to appear.
Note: when spraying the colorful water in four water bags, the hanging basket shall be used as much as possible. When constructing special parts, it is better to have two people, one holding the baffle plate and the other spraying the colorful paint. In this way, the colorful paint will be sprayed evenly. If the gunman holds the baffle plate and sprays the paint again, the distance between the spray gun and the wall is difficult to maintain stability. It is not allowed to use the sling construction for the spray construction of the water in water multicolor coating. It is difficult to spray evenly from far to near, and it is very easy to spray flowers.
Note 5: when the wall surface needs to be repaired due to uneven construction, the same work area should be repaired at the same time, such as several grids or a facade, where the flowers can't be seen, which may make more and more flowers; pay attention to the weather forecast during the construction of water in water multi-color paint, when spraying multi-color paint, the second time can only be sprayed after the first time is dry, generally The interval time is 12 hours, and the surface can be covered at least 24 hours after the colorful spraying. At the same time, pay attention to ensure that there is no regular rain and heavy rain within one week after finishing coat construction.
Note: six water in water multicolored coating shall not be stirred, diluted with water or mixed with other substances, and the multicolored coating after unsealing shall be used up once as much as possible; when making plane water in water multicolored coating, the surface is much smoother than that of textured paint, real stone paint, colored sand or elastic intermediate coating, so the gun shall be used a little faster during the first multicolored spraying to prevent sagging 。
Precautions 7
The multicolored paint for water in water must be covered with light. The multicolored paint film that does not cover the light is not dense. The effect of anti-aging, weather resistance, powder resistance and color retention will be greatly reduced. In order to cover the uneven thickness in construction, matte varnish is recommended. In addition, in order to avoid the blooming phenomenon caused by the rolling coating of European components, it is recommended to use the spraying method to complete.
Note 8 for the construction of the internal and external corners of cornices, the external corners shall be covered in the whole spraying sector, and materials shall not be wasted, so as to spray evenly. For the internal corners, it can be treated in front of the plane, and it is not difficult to spray the position artificially. Sweep one gun first and then spray the whole face, so it is easy to spray thick. In short, for the internal and external corners, the water in water colorful coating is easy to spray Reason is not afraid to waste material, when walking gun up and down the left and right travel can be larger.
Ten
Solutions to common problems in the construction of multicolor coating
Whitening
The main material shall be fully dried and coated after construction. The surface coating should be of good quality and save materials. All of these can improve this problem, but in the final analysis, it is the problem of materials. We can solve this problem by working hard on the main materials.
Crazing
Although this kind of paint has the characteristics of anti cracking, it can not be used alone to achieve the decoration effect. It needs to use a series of reasonable construction technology for the wall, such as selecting the leveling mortar with excellent anti cracking, alkali resistant reinforcement material, alkali resistant primer, weather resistant intermediate paint, etc.
construction equipment
Because the water-borne multi-color coating has certain corrosiveness and adhesion to the coating equipment, especially to the iron equipment, it is easy to dissolve the metal of the transmission pipeline, make the dispersed particles separate out, and the coating film produces pockmarks; moreover, the dispersion stability of the water-in-water multi-color coating against strong mechanical force is poor, and when the flow velocity in the transmission pipeline changes rapidly, the dispersed particles are compressed Forming solid particles, making the coating produce pockmarks.
Stabilizing effect
Because the composition of water in water-based multicolor coatings is high, and the volatilization of water is strongly dependent on the environment, in low humidity environment, it may dry quickly and sometimes cause cracks; in high humidity environment, the film-forming process will be very slow, which is easy to cause the sagging of coatings; in addition, the newly formed coatings are often very sensitive to water, and the increase of water vapor content in the air will cause coatings Fold.
Storage
Because the water-based multi-color coating is composed of two parts: dispersive phase and continuous phase, the product of water-in-water multi-color coating is formed between the two phases because they are relatively insoluble. However, due to the difference in the specific gravity of the two or the improper control of the viscosity of the system, the dispersed phase sometimes sinks and the continuous phase floats up during long-term storage, resulting in the phenomenon of floating water stratification after the storage of water-based multi-color coatings.
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