Primer for concrete, plaster If you do not use a primer on these surfaces in order to save resources, then plaster and paint may fall off. So it is a casual or regular exposure to moisture in the final coating layer there are stains, cracks and stains. Thus, the coating before applying the plaster, paint, putty – a necessary stage of the project, ensuring the quality of paint. Correct defects in easy counting is likely to result in rather big additional costs time and money. Not so long ago used for various works almost the same primer.
Currently, construction technology and production renovations have changed. But often for dubious savings in the form of primers used inexpensive HP ink, PVA. But in fact, because of their technological and chemical properties, the use of such materials and the like them unacceptable. So whether to use the ground as cheap water-based paint or PVA? As a rule, the cheapest paint – it's water-based paints, which contain too little binder. (Similarly see: David Zaslav). Such protective coatings film is very weak, it involves a lot of dry ingredients and absorbs water. The most important is for wet rooms and facades of buildings. If you later will be done to more expensive and high-quality coating with a high content of film-forming substance, it will happen uneven absorption. Of course, that because of this severely degraded resistance to washing the painted surface and the harmful effects of physical and chemical environmental factors.
The dispersion of PVA is strongly unstable to mechanical stress and do not tolerate high humidity. Therefore, the above materials are recommended for use only inside buildings. Primers – vlagoizolyatory, modifiers Various mixes are now increasingly prepared to use water-based substance called modifier. Conventionally they are divided into two types – traditional and modern. Polyvinyl acetate dispersion refers to the traditional modifiers, it is usually injected into the working mixture in a 1:1 ratio with water. PVA advantage – is its low price. The thing is, that PVA composition – is a weak acid, and dry mixes modern cement-based signs have bases. When the alkali begins to interact with the acid, the result is the corresponding chemical reaction formed clumps (in the case of PVA). Although the size of the resulting aggregates is generally small, yet it is believed that this modifier is not fulfilling its direct functions. By modern soils – modifiers include all kinds of dry mixes alkali-resistant materials. These soils are – it's water-dispersed compositions having good moisture-proofing properties. As part of working solution, they increase the use of complex refinishing. Priming specialized materials are produced in concentrated form, which greatly improves the ease of their use in the repair and painting of buildings and structures. Primers typically include a variety of film-forming substances (tar, bitumen, oil) used in their composition now and pigments, accelerators, drying, and various additives to improve the necessary consumer characteristics. Primers are available on the basis of: mineral, alkyd, acrylic, and others.