Ultra-complete paint knowledge, learn is to earn!

Why can't interior wall coatings be used on exterior walls?
water-based interior wall coating is composed of water, emulsion, pigment, additives, the interior wall coating and the outer wall coating is different because they are not the same environmental resistance. Generally speaking, outdoor coatings need to have a certain resistance to wind, rain, snow and sunlight (water, alkali, UV, antifreeze, anti-fading, anti-pollution, etc.), so the selection of raw materials in the formulation requirements are higher than the inner wall coating. The general interior wall coating experienced the environment is more moderate than the outer wall, so the general interior wall paint can not be used for the outer wall
the
.
the outer wall coatings available for the inner walls?
the performance requirements of the outer wall coating is higher than that of the inner wall, the exterior wall coating can of course be used for the inner wall. Because the price of exterior paint is higher than the interior wall paint, so the general consumer does not use, but sometimes the interior wall paint requirements or special requirements, can be used external wall paint, such as bathrooms, toilets, kitchens and interior, to make it more magnificent.
why was painting previously required for wall humidity and wall maintenance?
the walls are wet, on the one hand, the water in the cement or mortar that has just been constructed has not completely faded, and on the other hand, the humidity caused by the environment is too wet or rainy. Too wet walls can affect the adhesion of the surface of the coating, causing the surface of the coating to foam, crack, fade and promote mold growth. And in the process of evaporation and drying of water will make the wall salt alkali seep out and accumulate on the surface, it will damage the surface of the coating and make the color fade. Therefore, the humidity of the pre-construction wall is limited to less than 6%.
after the cement wall is molded and smeared with mortar, there shall be a maintenance period of at least 28 days, so that the cement is cured completely, the size is stable and the wall alkali seeps out and washed off before painting.
you do surface treatment and how many surface treatment methods are there?
no matter how high-quality the coating is used, the resulting coating surface will not be perfect in terms of performance and efficiency if it is not adequately and properly surfaced in the past. The surface treatment varies from substrate to substrate, but the purpose is the same, i.e. to give a dry and stable substrate.
surface treatment methods: high-pressure water flushing, polishing, temperature control, requiring the maintenance period of the substrate, shedding, acid washing, solvent degreasing, sawing, blasting, repair, etc.
water-based interior wall coatings with high viscosity can be sprayed directly?
high viscosity of water-based interior wall coating, not diluted or a small amount of dilution, can be directly sprayed with airless, and the effect is better. If sprayed with air, the water-based interior wall coating must be diluted to the corresponding viscosity, because different spray guns, different air pressure, the required water-based interior wall coating viscosity is different. Water-based interior wall paint requires the amount of paint and fog of the spray gun, the spray is large.
can I choose a brushing tool? What problems should I be aware of when using a new pen and a new hard brush?
, depending on the size, nature and paint material of the paint surface, different hard brushes and liners are selected. Brush primer and toning paint should be used flat-shaped hard brush, brush varnish should be used brush thinner, better elastic flat brush, bristle brush elasticity and strength than the row pen, suitable for brushing larger viscosity paint.
When using a new hard brush, before painting, the hard brush should be placed on sandpaper 1, back and forth sanding the head of the bristles, so that the hair grinds smoothly and then take a small amount of paint on the old surface, brush back and forth several times, so that its bristles fall off, to ensure that the brush does not fall off easily.
When using a new pen, in order to reduce hair, before use, you should use your fingers back and forth to move the brush hair, so that the unadhesive wool fell out, and then soaked in hot water, flatten the pen, and paper wrapped, let it dry.
why is it best to paint water-based interior wall paint more than twice?
water-based interior wall paint is painted twice mainly in order to achieve its due cover and coating surface performance. Because the coating cover force and coating surface performance and paint surface thickness have a certain relationship, so in order to achieve the best decorative and protective effect, water-based interior wall paint is best painted twice. The premise is to carry out the construction according to the substrate treatment and dilution rate required by the instruction manual.
the water-based interior wall paint after brushing once can be repainted a second time?
the interval between water-based interior wall paint brushes, depending on the specific construction conditions. Mainly the first time it's all done and then the second time. Some paints with slower drying can extend the recoying time.
the same effect as applying a thick layer to a thin layer?
water-based interior wall coating generally requires two applications (under normal dilution), too thick coating will cause the surface of the coating cracking, and the appearance level will not be good. Although the formulation is designed to take into account the condition of the thicker coating surface, it does not mean that the water-based inner wall coating can be over-diluted when painted many times, because the excessive dilution of the water-based inner wall coating will cause the coating surface to powder.
do I have to paint after I've finished batching putty?
suitable for building walls more putty, mainly water-based putty and nitro putty, if it is water-based putty, should be painted after 24 hours, if it is nitro putty should be painted after 5 hours, mainly according to the putty dry after brushing paint, otherwise the surface of the paint easy to bubble, peeling.
. How should substrates such as gypsum boards and asbestos cement slabs be treated?
gypsum board, asbestos cement slab should be fully dry surface before painting, because they have a certain alkalinity, it is recommended that the first layer on it with closed primer after coating.
b. The old wall paint water-based interior wall paint without brushing primer has no effect, the wall how to deal with?
the old wall is relatively strong, the wall alkali is not serious, you can clean the wall and paint directly. If the surface of the coating is loose and the surface behind the shovel is uneven, the putty needs to be re-approved and the quality of the finish must be guaranteed with primer.