What Primer To Choose, Types Of Primers And Technical Characteristics, How Long It Dries, How To Wash The Primer, What Is It For

2023 Author: Philip Bishop | [email protected]. Last modified: 2023-08-25 07:54

• What is a primer for?
• The choice of primer for different surfaces during repair
• Adhesive and hardening primer
• Primer requirements
• Acrylic special primer
• Glyphthal special primer
• Perchlorovinyl special primer
• Polyvinyl acetate special primer
• Phenolic special primer
• Polystyrene primer
• Basic rules for using primers
• Primer application
• How to wash the primer

Priming the surface before applying plaster or other coating is of no small importance during the construction and interior decoration of premises. The main purpose of the use of primers and their purpose is to increase the adhesion of the base of the surface with subsequent layers of decorative finishing applied to it. Plaster, paint, tile glue applied to a surface that has not been treated with a primer mixture can peel off or crack over time, since brick, concrete and wood surfaces have high absorbent properties. Thus, the question naturally arises - which primer to choose when renovating an apartment and for which surfaces which one is best suited?

What is a primer for?

It is easier to apply paint, decorative plaster, various adhesives and mastics to surfaces treated with primers, and the antiseptic components included in the primers protect the surface from the appearance of mold. Currently, there is a fairly large selection of primer mixtures, or as they are also called special primers, for a variety of surfaces and for a variety of purposes, according to their properties and components included in their composition, they are divided into several categories. Depending on the type of room and what kind of coating is planned to be applied to the primed surface, an appropriate primer should be selected.

The wrong choice of primer mix can incur additional costs for renovation of the premises, and the use of primers that are not intended to cover the surfaces of indoor living spaces can cause serious harm to health. Primer mixtures are a liquid homogeneous mass, which includes polymer components and various fillers and are used only as a first layer for coating with other materials. Due to the fact that primers do not have decorative properties, they are never used in the front finishing of premises. So we figured out what the primer is for, let's move on.

The choice of primer for different surfaces during repair

When renovating or finishing a room, you need to understand what a primer is for. There are several reasons why a primer is needed for finishing work.

When carrying out work on putty, painting walls, wall tiling, it is necessary first of all to prime the surface for better interaction, adhesion of the base and the applied material. Also, thanks to the primer, there is a more uniform distribution and absorption of paint, putty, wallpaper glue. The cost of priming and application work is generally low, but it allows to increase the strength and durability of the applied finishing layers.

So the need for a surface primer cannot be underestimated. There is a wide variety of primers, both universal and for specific substrates.

Why do you need a surface primer for repairs? Basically, primers are used for the primary preparation of the base, to improve adhesion between the surface and the applied layer (between the wall and plaster, between plaster and putty, between putty and paint, etc.). And also for changing and improving surface properties: reducing moisture absorption for porous surfaces, improving absorption for dense surfaces, preventing the occurrence of mold and mildew for surfaces in wet rooms, protecting against destructive factors (corrosion, decay, etc.), drying accelerators etc.

What is a primer for:

1. For porous surfaces (aerated concrete, foam, brick, plaster), the primer is applied to strengthen the surface and reduce the absorption of the applied putty or glue into the material. That is, to improve grip performance. For such surfaces, deep penetration primers are used, which create a special film that prevents the loss of moisture from putty, glue or other finishing materials, and, accordingly, prevents the loss of bonding properties. (For example, Ceresit CT14, CT17, CT17 super primer).
2. For monolithic concrete surfaces, which are dense and, conversely, do not absorb moisture well, mineral-based primers with cement as a binder are used. For example "Knauf" Betokontakt. To improve the adhesion of the substrate and for example plaster.
3. For wooden surfaces, primers are used to protect wood from decay, improve adhesion to paint or varnish, reduce absorbency, which reduces material consumption during finishing. There are also special antiseptic primers that protect wooden structures from insects, rotting, etc. Antiseptics are mainly used for wooden structures of roofs and floors, which are not subject to further finishing. For example, an antiseptic primer Pinotex-Base.
4. For surfaces in rooms with high humidity (showers, bathrooms, sauna rooms, etc.), they are used to create a waterproofing layer to prevent moisture from penetrating into the base. Also, the primer should prevent the appearance of condensation and mold (for example, a deep-penetrating primer with antiseptic "Polimin" AS-5a)
5. For removal of mold, microorganisms. If you need to tidy up the surface inside or outside the building, which has been exposed to moisture for a long time and mold, fungus, moss, etc. have formed, first you need to install and eliminate the source of excess moisture, and then mechanically (without the use of water) repair damage and treat with a special primer and leave for 8-10 hours. (For example, Ceresit CT99 primer).
6. For metal surfaces: for metals such as steel, cast iron (ferrous metal), primers are used both to improve adhesion and for anti-corrosion protection. For this, zinc-containing alkyd primers are used. (For example, ГФ-021). In case there is already rust on the surface. For ferrous metals, so-called "rust converters" are used, which will stop the degradation process and convert rust into a protective coating. If it is necessary to paint galvanized steel sheets, aluminum products (non-ferrous metals), a primer for non-ferrous metals is used for surface preparation.

These positions generally explain what the surface primer is for. The use of a primer is important for any process of cladding, insulation, finishing. This simple process will allow you to perform the process at a professional level and make it of high quality.

Adhesive and hardening primer

Regardless of their water-repellent functions, primers are adhesion and strengthening. In the first case, the primer promotes better adhesion to the surface of finishing materials.

For example, if used in a bathroom on a pre-plastered wall, the primer will allow the tile to adhere more strongly to the substrate. In this case, the role of waterproofing will be performed not only by the primer, but also by the ceramic tile itself, which has a low moisture absorption coefficient.

A reinforcing primer is usually used when processing loose surfaces. And since the walls are usually plastered and leveled from the inside of the room, it is most rational to carry out such work outside - before finishing the walls with the same decorative facade plasters.

A hydrophobic primer is an excellent insulating agent

Thus, the treatment with a hydrophobic primer takes place both in outdoor work and in the decoration of rooms with high humidity, or a high chance of leaks - in the bathroom or laundry room, as well as in the kitchen. In this case, this type of primer, in combination with other insulating components, allows you to create a kind of hydro-barrier that guarantees protection of the premises below from flooding. So, a waterproofing material is usually laid on top of a concrete floor slab impregnated with a primer, and only then the installation of a concrete screed and finishing of the floor, such as tiles, takes place.

Aerated concrete walls without proper treatment have disadvantages: low resistance to pressure and crushing, scratches and chips of the front surface; high hygroscopicity - the ability to absorb and retain water, and in such a water-saturated state, to reduce to almost a minimum its qualities of heat protection and sound insulation.

In order to help aerated concrete to show its properties as best as possible and get rid of shortcomings, structures made of it need to be primed by coating and impregnating with special compounds, for example, Grunadirmittel from Knauf, creating a leveling and smoothing protective layer up to several millimeters thick, which allows finishing work - plastering, facing, wallpaper and others.

Primer requirements

Usually they are liquid polymer emulsions or dispersions, which, after distribution on blocks of aerated concrete at the end of the setting (or polymerization), change the quality of the outer surface, which receives: hydrophobic properties (stops absorbing water); vapor permeability (allows air saturated with moisture to freely migrate through the vapor-permeable layer from the room to its outside through the outer walls, preventing the formation and accumulation of water condensate inside the block); biological protection (antiseptic components prevent the subsequent formation of fungus, mold, the reproduction of harmful microorganisms); adhesive qualities (the ability to reliably hold plaster and other similar types of finishes on itself, both in liquid form and in a set to a solid operational state). The preferable primer is best to use the most common grades:

Knauf Grundiermittel. One of the best deep penetration primers. To bring it to working condition, it is diluted in a ratio of 1 to 3. Produced in a 15 kg container, consumption is about 300 g per 1 m2.

Volma-Universal. Deep penetration composition, most often used to prime aerated concrete before plastering in order to increase adhesion and hardening, is suitable for external and internal application. It is bottled in 10 liter containers ready for use. Consumption - up to 150 ml per 1 sq. meter.

Tex-Profi. For internal use only. Up to 15 m2 can be treated with one liter of the prepared solution. It is sold as a concentrate diluted with water in a ratio of 1 to 3, in 0.9 kg plastic bottles up to 9 kg canisters. 5. Prospectors. Emulsion of deep penetration, has a good effect on the porous structure, hardening the surface, which can then be applied with plaster. Consumption - up to 200 ml per 1 sq. meter, available in a ready-to-use state in plastic 10-liter canisters.

Types of primers, technical characteristics of compositions

Designed mainly for covering wooden surfaces, for the subsequent application of a variety of finishing coatings, including cement-sand coatings. Thanks to the treatment of the wooden base with alkyd primers, the surface of the tree acquires an expanded structure, thereby increasing its "adhesion" with the subsequent coating applied to it. The time for complete drying of alkyd primers at a temperature of + 25 ° C is 10 - 15 hours. Alkyd primers are well suited for the treatment of residential surfaces.

Acrylic special primer

It has a high penetrating power and is considered a universal primer. It is used for treating almost all types of surfaces such as wood, concrete, chipboard or plaster, both old and fresh. It is also excellent for the treatment of porous or very loose (eg old plaster) surfaces. Penetrating deep into the pores, the acrylic primer significantly increases the adhesion of the porous surface. The only exceptions are metal surfaces, since after some time rust stains may appear on them. Drying time for this type of primer is no more than 5 hours, it is also worth noting that acrylic primers are practically odorless.

Glyphthal special primer

Designed for surface treatment in dry rooms, as well as for application to metal surfaces as a first layer. Glyphthal primer mixtures dry completely at room temperature within 24 hours.

Perchlorovinyl special primer

Just like an acrylic primer, it can be used to cover any surfaces, including metal, but it should be borne in mind that it is impossible to use this type of primer in indoor living quarters, due to its increased toxicity of its components. Perchlorovinyl primer dries no more than 1 hour.

Polyvinyl acetate special primer

Synthetic primer mixture consisting of latex or polyvinyl acetate dispersion. Usually used only to prepare surfaces for further coating with polyvinyl acetate paints. The time for complete drying of this primer is 15 to 30 minutes.

Phenolic special primer

It is used for priming both wood and metal surfaces as a first layer. As well as perchlorovinyl primer, it is not recommended for use in indoor and residential premises. Phenolic primers dry on average from 10 to 15 hours.

Polystyrene primer

Most often used for priming wood or plastered surfaces. However, this type of primer cannot be used in residential premises, since they contain highly toxic solvents. For the drying time of the primer, see the application description.

Basic rules for using primers

To ensure high efficiency of the primer application, certain rules and requirements for its use must be observed:

Do not purchase a primer with an expired or expiring shelf life, as the quality of the solution will be reduced.

Before applying the primer, the surface to be treated should be prepared, which includes cleaning it, removing swelling and peeling of old coatings and plaster, deepening and widening the formed cracks.

When applying the primer with a roller, brush or spray gun, the uniformity of application must be observed without skipping the front and end areas.

If the solution is quickly and strongly absorbed by the surface to be treated, apply a second coat of primer after the first coat has dried.

After applying the primer, you need to give it time for complete drying, the duration of which depends on the composition of the primer and the external conditions, room humidity and temperature.

For inexperienced homeowners, remember that using a primer is always better than ignoring it. The principle “you can't spoil the porridge with butter” works here, and the quality of the finish only increases with it.

Primer application

The tool used is usually a roller for a high processing speed, or a brush if you have to cover difficult areas or small surfaces.

Important! When applying the composition, it is extremely important not to leave untreated areas, since otherwise all waterproofing measures will be meaningless. The joints must be processed with particular care.

• More liquid formulations can even be applied with a spray, but thicker ones can be smeared with an ordinary spatula. Typically, the last application is a mineral primer;
• In general, the preparation rules in this case are standard - the seams must be repaired, the surface must be thoroughly cleaned and, if necessary, degreased. Since fatty places do not have to be visible at all, it is necessary to walk with acetone or white spirit over the entire treated surface as a prophylaxis;
• When decorating walls or floors with tiles, a compound can be added to the glue to improve its water-repellent properties. But there should be no more than 4 percent of the total volume of hydrophobic impregnation, so as not to reduce the bonding capabilities of the adhesive composition;

• In the process of applying the composition, the first layer is absorbed into the material almost completely, therefore it is necessary to apply the second, and sometimes the third layer;

  It is necessary to continue finishing work at least half a day from the application of the last layer of the primer, since this is the time required for the composition to acquire its hydrophobic qualities;

• The temperature at which work is to be carried out must be at least 5, but not more than 25 degrees Celsius. High humidity also does not contribute to the effective application of the composition. Storage of the primer should not be carried out at temperatures above 30 degrees;
• Work should use overalls or other means of personal protection;

Sometimes the primer is frozen. And to defrost it, you just need to leave the composition in the room for a while. It is contraindicated to heat the composition.

How to wash the primer

If you get dirty with it and do not know how to wash the primer or clean the tool, then in most cases Mr. Muscle for windows, Silit for toilets and an abrasive brush will help. If the tiles are dirty and nothing helps, then you will have to go to a specialized hardware store and look for modern means. You can also try this:

1. Keep stains covered with wet rags for several hours. The primer swells slightly and separates more easily.
2. Use solvents - gasoline, acetone, turpentine, 646, 647, toluene, ethyl acetate.
3. If the glaze is acid-resistant, use acidic household sanitary ware.
4. Concentrated vinegar - essence works well (only work in a gas mask or in a professional mask with good filters, otherwise you can easily burn your lungs).

The main thing is not to debug this procedure, otherwise it will be even more difficult to wipe off when the primer dries well. Now you know which primer to choose, what it is for, what types and technical characteristics there are, how much it dries and how to wash it if you do not handle it carefully and hit the surface.

Video on the features of the use of primers

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