Common knowledge of coating: importance of sealing primer in coating construction

Core tips: latex paint is more and more popular with consumers for its environmental protection and practicability However, there are great hidden dangers in the construction, especially in the construction of new exterior walls in the early winter of the north and the coastal areas The base course of building exterior wall is generally concrete, cement mortar or lime cement mortar The curing period of cement mortar is 14 days in summer and 21 days in winter The curing period of cast-in-place concrete is 21 days in summer and 28 days in winter The curing period of lime cement mortar is longer, 30 days in summer and 90 days in winter In the cold north, 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: latex paint with its environmental protection, practicality more and more favored by consumers However, there are great hidden dangers in the construction, especially in the construction of new exterior walls in the early winter of the north and the coastal areas The base course of building exterior wall is generally concrete, cement mortar or lime cement mortar The curing period of cement mortar is 14 days in summer and 21 days in winter The curing period of cast-in-place concrete is 21 days in summer and 28 days in winter The curing period of lime cement mortar is longer, 30 days in summer and 90 days in winter In the cold north, the maintenance period should be extended properly However, due to the construction period requirements, many buildings need to be coated with exterior wall coating in a short time The pH value of the mortar which has not reached the curing period is generally greater than 13 There are many unhardened cement particles in the mortar, a lot of alkaline substances, and many soluble salts There are many pores between sand particles and unhardened cement particles These salts are very easy to use these pores and the pores of emulsion paint film to migrate to the surface of the film, making the film appear alkali return, salting out, color biting, peeling and other phenomena It not only causes great loss to the owner and the construction party, but also affects the promotion and application of latex paint 1 The formation mechanism of the phenomenon of efflorescence and salting out the appearance of the phenomenon of efflorescence is closely related to the chemical reaction that forms the solid mechanical properties of concrete The hardening process of cement is the chemical reaction of water and calcium silicate, which produces calcium hydroxide and hydrated calcium silicate The latter makes cement have good mechanical properties However, there are also sodium silicate, potassium silicate and other substances in cement, so NaOH, Koh, Ca (OH) 2 will also be produced in the process of cement hydration When the hydroxide migrates to the substrate surface and contacts with CO2 in the air, it reacts to generate carbonate and water, which will be left on the substrate surface after water volatilization (as shown in the figure) 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,