How to prime MDF before painting?

Painting of surfaces made from MDF is done not only for decorative, but also for protective purposes. The main advantages of painting panels yourself:

The coating is resistant to elevated temperatures, which allows you to place even hot dishes on the kitchen surface.
High-quality painting of MDF with enamel allows you to make the facade more refined and original, giving it a unique design. For example, you can decorate your furniture with interesting decor in the form of pearls, mother-of-pearl, metallic and so on. To achieve this, various fillers are added to the paint.
Safety for health, since only high-quality paints and varnishes are used.

Painted MDF panels not only look better, but are also more reliable and durable.
Disadvantages of painting MDF panels:

higher price compared to film coating;
If you use low-quality paint, over time the painted facade may fade under the influence of sunlight.

Painting MDF at home - what are the features?

Before you figure out how to paint MDF facades at home, you should understand what positive and negative aspects this procedure has. The advantages of painting MDF include:

Obtaining a resistant coating of furniture surfaces to high temperatures. Most often, MDF panels are found in the kitchen, so after painting, you can place hot utensils on it without fear of damaging the surface;
To change the appearance of objects, giving them a unique coating, pearl, metal, and mother-of-pearl additives can be used to obtain an original design;
Harmless to health, paints for MDF are made only from safe elements.

But there are also disadvantages to coloring:

If you choose a low-quality paint, the color will fade under the influence of ultraviolet radiation;
High cost compared to film coating.

Selection of materials for painting

In principle, all paints for MDF are selected taking into account the composition of the material. And this is, first of all, a fine wood fraction, which means that paint solutions for wood are suitable for the job. But to obtain a truly high-quality coating, it is advisable to use special mixtures.

When choosing materials for painting MDF, you should pay attention not only to the color, but also to the purpose of the paint

Polyurethane enamels

This material should be preferred for the following reasons:

The coating is wear-resistant and can withstand exposure to household chemicals.
The solution does not have an unpleasant odor, which makes it possible to carry out work in cramped home conditions.
The mixture can be applied using a sprayer, roller and brush.
Painting MDF with enamel is done independently; this procedure does not require professional skills.

Naturally, when choosing this material, they pay attention to the manufacturer. It should be a well-known brand that is sold in specialized stores. When purchasing a product from an unknown manufacturer, there is a high probability of getting a fake.

Advice! If it is not possible to select a polyurethane composition, then pay attention to alkyd enamels and paints (oil and acrylic).

Thus, the question of how to paint MDF panels is no longer a problem. But another dilemma arises - the surface needs additional protection, how can this be done?

Indeed, to increase resistance to mechanical stress and protect against chemical compounds, varnish is used. And for such work, a two-component polyurethane composition is especially suitable, which has all the desired parameters.

Types of priming compositions

The primer mixture consists of polyurethane and various solvents, but depending on the material of the base being primed and its location, primers may differ in composition due to special additives that give them additional properties. According to the degree of curing there are:

Single-component, consisting of a solvent and a base substance. A one-component polyurethane primer is often used for interior work on MDF or wood; it is well suited for concrete walls. Its fluid structure penetrates deeply into an MDF board or concrete wall, strengthening and leveling the substrate, increasing adhesion for applying the finishing coating.
Two-component, produced in the form of two bottles (polyurethane mixture and hardener), which are mixed before use. Two-component polyurethane primer is stronger, but less fluid due to the presence of a hardener, well suited for outdoor use or for high-traffic concrete floors. If the solution contains a zinc-filled component, this will provide anti-corrosion protection to the metal. Rarely used for wood or MDF. Often, when priming is the only method of painting, for example, when protecting the floor in a workshop or garage, it is worth using an enamel primer, which will strengthen the concrete structure and protect it from destruction.

Preparing MDF for painting

Before painting MDF, it is necessary to prepare the surface of the board itself. What does the preparation of MDF boards for painting include:

1) Sanding MDF to prepare the surface of the board for primer. Thanks to grinding with grain 120-240, firstly, surface unevenness will be smoothed out, and secondly, a layer of paraffin will be sanded off, which would prevent the primer and paint from being absorbed into the wood. On complex curves, it is better to sand the MDF with an emery sponge, or even avoid sanding thin cutters at the initial stages. Still, MDF is a rather fragile material, it’s better not to fray it too much.

2) Before painting MDF, you need to make sure that the material does not need putty. For example, you need to putty large dents, edges, or gaps between parts if the product consists of several elements. Acrylic putty is best suited for this purpose - it is quite elastic and will not crack over time. After drying, its remnants are carefully removed, and the MDF surface for painting is sanded with sandpaper.

3) Prime MDF before painting. As a rule, MDF is primed twice before painting in order to give the board surface an ideal smoothness. At the first stage of priming MDF, the insulating primer is sprayed using a spray gun (nozzle - from 1.6 to 2.4 millimeters, 2-4 atm.) at the rate of 90-100 grams/"square". This primer should prevent the pile of the MDF board from rising and absorbing paint or varnish: the primer gets into the loose areas of the MDF, and the paint will not sag after application. After the primer has dried, the surface is sanded with sandpaper or an emery sponge, but very carefully - a thin layer of primer can be easily wiped down to the MDF board.

The second primer is carried out with white polyurethane primer at a rate of at least 150 grams/square. The primer layer should be given time to dry - 12-24 hours, and then sanded. If pellets of primer are visible on the skin, it means it has not dried yet.

How can I prime MDF before painting? A mixture of your chosen paintwork material for painting with the addition of water. For example: 25% water-based enamel, 25% varnish, 50% water.

If we talk about general recommendations for priming MDF, then it is carried out with a spray gun, starting with the most complex elements of the cutters, then moving to the edge, and then to the rest of the surface. First, the part is covered lengthwise, then crosswise, overlapping.

Classification

Primer compositions are:

Acrylics. They are usually one-component. Such primers are used primarily for treating MDF and wooden surfaces. Due to their ductility, they penetrate deeply into the material, fill the pores and level the base. These properties are especially important when applied to non-laminated MDF. Acrylic solutions are also effective when treating concrete bases indoors. An important advantage of the mixture is non-toxicity.
Alkyd. These solutions are used for exterior finishing of wood and MDF. Such compositions reliably protect the material from destruction. If it is necessary to emphasize the texture of the base, it is more advisable to use enamel primer. It will also serve as a finishing coat.
Epoxy. Such mixtures are used primarily for treating metal surfaces.

Painting MDF with auto enamels

In the article “MDF facades” I described the MDF finishing system. The fact that there is a whole system of finishing MDF is understandable, but is it possible to paint MDF with auto enamels? I read this question on some forums on the Internet and heard it from fellow carpenters.

I also heard statements from some Painters that “There is no difference in painting MDF, between auto varnish and special paints,” they even claim that auto varnish for MDF facades is even better. This is the topic I’m going to talk about today.

Frankly speaking, I am not a supporter of technology violations,

and I think that if there is a special system for painting MDF, then you need to use it.

Painting MDF with auto enamels is possible (this is my personal statement) when only these paints and varnishes are available, as usual, deadlines are running out, and the client, by and large, doesn’t care what material the facades are painted with, as long as everything is beautiful.

In my practice, I have had to use automotive materials on MDF facades more than once, so I have already formed a definite opinion.

So. the facades were sawn to size, prepared for painting and brought to Malyarka.

As in finishing with special paints for MDF, before starting it is important to review everything, that is, accept the product from the carpenter. The facades should be sanded both from the ends and along the plane with sandpaper, ultimately no rougher than 180 (these are my recommendations).

This shouldn't happen!

In this case, you should return it for repairs, or pick up the tool and fix it yourself. I took a wheel with 320 abrasive and sanded everything “in a circle” (both the plane and the ends)

After the facades are prepared for painting, we begin painting, of course, understanding the technology.

The MDF finishing system implies:

Soil insulator (you can read about it here.)
Intermediate grinding
Pigment primer (1-2 layers)
Grinding
Enamel
Varnish (if required)
Polishing (if required)

When painting with automotive paints, the technology is the same. only in addition I needed to create a metallic effect.

Application

The application of a polyurethane substance does not differ from the technique of applying other primers. But you need to take into account that polyurethane primer is not intended for use with a spray gun. Concrete walls and wooden bases can be primed using rollers, which can have different sizes. With them, a large surface is painted quickly and easily.

Brushes will help where rollers are not so effective, for example, in hard-to-reach areas. They can be used to tint, but over a large area they are useless.

It is permissible to apply primer to an unprepared surface. But it’s better to prepare the foundation well:

clean off old finishes, remove dust;
Rinse;
dry;
large cracks should be filled with putty; small cracks will be filled with primer.

After this, you can apply the solution. It is distributed evenly using a roller. After the first layer has dried (about 5 hours), you can apply the second. The polyurethane primer is applied vertically in the first layer, horizontally in the second, since this way the mixture will be better absorbed into the base. Two applications are enough, after which you can begin decorative finishing.

What primer should I use for MDF?

MDF is a porous material that absorbs paint and moisture very quickly. Therefore, you must prepare the material thoroughly before you start applying paint. If you use the wrong primer, the paint you apply on top will not be able to adhere properly. This can lead to the formation of peelings.

Using the right type of primer is vital if you want great results. Avoid using latex primer on MDF as it will cause the wood to expand and affect the texture of the material. The same problems arise when using water-based primers.

Your best bet is to find a solvent-based primer. However, you should be careful with all-purpose primers. The MDF manufacturing process uses a variety of chemicals and adhesives that can react poorly with the wrong primer. You need to use a primer suitable for MDF as this will prevent it from deteriorating.

How to apply primer?

The cut edges of MDF are particularly porous, so special care must be taken to seal these areas. Apply two to three coats of primer before painting the MDF. For best results, it is best to lightly sand the MDF between coats of primer. Wait until completely dry before you begin painting; the primer may not be completely dry.

Once you have removed the dust, lightly wipe the surface with mineral spirits. This step allows future primer coats and paint coats to be applied much smoother. You may need to spend a little more time completing these steps, but the best results will come from properly prepared MDF.

Priming and finishing the edges of MDF

Learning how to paint MDF is relatively simple, however, before you start applying the paint coat, there is one very important step that you cannot skip. As mentioned earlier, the edges of MDF board are particularly absorbent. MDF primer works well on the surface, but you need to pay special attention to the edges.

There are several materials you can use to seal the edges before painting the MDF. Whatever substance you choose, the technique for sealing the edges is the same; apply the treatment, lightly sand the edges, then add another coat.

Sealing MDF edges with PVA glue

This is a popular method for sealing edges, however if you are not careful it can cause some problems. Between layers of glue you need to lightly sand the edges. If the PVA layer is too thick, you will not be able to sand it properly.

So, if you are going to use PVA to seal the edges, make sure you apply a very thin layer each time. You must be sure that the PVA is laid down in an even layer over the entire surface. You can do this with a small roller.

Sealing the edges of MDF with Shellac

Shellac is also a good choice for sealing the edges of MDF. When it dries it creates a very hard layer.

You can also seal the edges using a regular oil-based primer.

Paint options for MDF.

There are several ways to paint MDF and many decoration options. Using the right paint is essential to achieve the best results. So what exactly is the best paint for MDF?

As you already know, water and MDF do not mix well together. In theory, when you paint MDF that has been properly primed, the water-based paint shouldn't harm your wood. However, there are moments. Water causes the fibers to rise. With large surfaces, on bends, corners and not carefully treated with a primer, roughness will appear in places.

Standard water emulsion may produce inconsistent results and the paint may flake off quickly. Instead, choosing an oil-based paint will yield better results. However, you should be aware that oil-based paints may have a stronger odor than water-based paints.

Acrylic and latex paints are also suitable for MDF. If you are painting for the first time, you will notice that these paints are easier to use than oil-based paints. Acrylic and latex paints can only be thinned with water, while with oil paints you will need to add paint thinner. A paint to water ratio of 70:30 should give good results.

Advantages of polyurethane primer

The properties of polyurethane primer make it possible to protect any type of metal surface and extend its service life.

Multifunctionality.
The primer is suitable for external or internal finishing. It doesn’t matter whether we are talking about the roof of a complex structure over a sports stadium or pipes inside a residential building.
Flexibility.
Primer protects flexible or hard metal. It is also used to cover rolled sheet material.
Easy to apply.
You can work with polyurethane primer without prior preparation. The composition can be applied over rust.
Adhesiveness and anti-corrosion.
The primer penetrates into the pores of the product, improves adhesion, is suitable for surfaces that absorb moisture, and protects against corrosion.
Economical.
The consumption of polyurethane primer-enamel is from 80 to 100 grams with a thickness of 40 microns per 1 m2. For comparison: water-dispersion primers consume up to a kilogram of mixture per meter.
Drying speed.
Polyurethane primer enamel “Khimtrust” dries at +10 ⁰C for 40 minutes (from dust) and two hours when it comes to interlayer curing. At +35 ⁰С - 12 minutes (from dust) and 30 minutes with interlayer exposure.

Can MDF be painted?

To answer this question, you need to understand why this might be needed at all. The material itself has a medium or low density and over time, for many reasons, various defects may appear on the surface, such as scratches, fading in the sun, or loss of gloss. All this spoils the appearance of the product. And then the owner thinks about how to correct the situation without completely changing the MDF.

There are a number of reasons why painting MDF at home is required:

Any mechanical damage. Any products made from MDF have a thin layer of laminated paper, which can burst upon impact, exposing the core of the product;

Color fading. In conditions where the surface of MDF is constantly exposed to sunlight, it fades. In addition, the surface loses its glossy shine and appearance;

Jumps in degrees also have a negative impact on MDF. This is a material that consists of wood fractions, and wood is known to absorb moisture well. Therefore, an MDF product can become deformed and swell. And, conversely, in dry air, MDF dries out and cracks. At high humidity, the adhesive substance in the material loses its properties, which leads to peeling of paper and shavings.

If you encounter such problems, you can fix it yourself. To properly paint MDF, you need to carry out a number of preparatory work. In addition, you should have the following devices:

to apply a primer layer and paint to furniture facades, it is best to use a spray gun;
Brushes with soft but elastic bristles will also do an excellent job. Especially if there is MDF milling;
For products without milling, a roller is suitable.

MDF primer for painting

MDF painting technology includes several stages. And the first one is the primer. But before it is carried out, it is necessary to prepare the surface, sand it, remove sharp edges and degrease the surface. If there are any cracks, they need to be puttied. After the material has dried, the surface must be sanded again.

How to prime MDF before painting? The primer is carried out in several stages. The first to use is an insulating primer, which is sprayed from a spray gun at a rate of 100 grams per m2. But this applies to non-laminated products. Otherwise, you can skip this step.

This stage is necessary so that the paint or varnish does not absorb and sag after some time. The primer seems to fill in all the small irregularities and depressions. After it dries, the coating needs to be sanded again.

The second layer is white polyurethane primer. Consumption - 150 grams per m2. At the same time, it dries for a long time - about 24 hours.

All this is done with a spray gun, but if you don’t have one, you can also take a brush. The first layer is made along, and the second - across the first.

How can you paint MDF?

Before painting an MDF facade at home, you need to select the right materials for these purposes. It is worth remembering that painting should be carried out at approximately +20C and air humidity of 50-80%. All paints will not be suitable for these works, because MDF is, in fact, wood, and therefore the paint must be designed specifically for this material. This includes:

water-based compositions (water-based). Often used for significant volumes of work;

compositions based on alkyd enamels. The coating is resistant to abrasions, but can easily fade in the sun;

silicone materials. They have water-repellent characteristics and can withstand high temperatures;

polyvinyl acetate materials - suitable only if the product is not subject to heavy loads or damage;

oil-based compositions are moisture resistant;

acrylic-silicone compounds. They withstand damage and also prevent the proliferation of harmful microorganisms;

special paint for MDF facades;

Many also prefer powder painting - it is more durable and the coating is more even.

Any paint for furniture facades and other MDF products must be of high quality and as harmless as possible to humans and the environment. So you can be sure that the product will serve you for a long time and will retain its original appearance.

All this is applied with a spray gun, but if you don’t have one, brushes will do. However, with a spray gun the coating is more uniform and even.

Applying paint

This stage is actually very simple. First you need to prepare the paint material according to the instructions offered by the manufacturer. Next, you need to take your spray gun and set it up so that it sprays the material into small areas. This way you can save paint, and the coloring itself will be of higher quality.

You should start painting MDF furniture and other products from the most problematic areas, such as cracks or damage. It is advisable to paint in several layers, allowing each of them to dry thoroughly.

Varnishing

The last step is varnishing the wood. Here you need to adhere to the following recommendations:

the varnish is prepared taking into account the manufacturer’s requirements;

You should start varnishing from the ends and milling areas;

the first layer of varnish should dry well, and then it is treated with 1200 sandpaper;

dust must be thoroughly removed with compressed air from the compressor;

the second layer is applied;

some products must have a varnish layer of 0.5 mm, and therefore up to 4 layers may be required;

after this, final sanding is carried out with sandpaper 1500, 2000, 3000;

Surfaces need to be polished with a special polishing machine and special paste.

As you can see, painting MDF panels with your own hands is not such a difficult task. The main thing is to carry out all the steps sequentially, not skip anything and use only high-quality materials. And then your furniture, doors, laminate flooring will sparkle with new colors, be transformed, and the room will look new.

If you do not use an insulating primer, but use regular primer, then it will “sink” into the MDF, especially at the ends and milling areas, this is due to the porous structure. Typically, polyurethane primers are used as insulator primers, in the Renner line these are FI M199, FI R800, but there is also a water-based insulator for environmentally friendly finishes YL M641. The insulating primer is applied in a small layer, sufficient to fill the pores and thereby compact the top layer of MDF.

If you do not use an insulator when finishing MDF, you will have to apply more layers of regular primer and wait until it fills the pores - this is more expensive and takes longer.

Grinding

When applied to the surface of MDF, the primer insulator raises the pile, because of this no serious sanding is required; it can be removed very easily, using a regular sanding sponge with P180 grain.

Glossy finish

If a glossy finish is desired, the subsequent coat must be perfectly smooth. For the best quality gloss in the subsequent coat, it is recommended to use polyester primers such as PL R310 or PL R013. If you use primers of other chemical groups, you can also get gloss, but the best quality can only be achieved with polyester.

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How to paint a wooden house? 0
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24-95080-9734-2-350, Matera Steel, PVC film for MDF facades

Impeccable optical characteristics of films - PVC films are produced according to modern recipes.

Exceptional wear resistance, operational and technological properties.

Strict European quality standards - all films do not contain plasticizers, heavy metals, or other impurities hazardous to health.

Versatile possibilities for high-quality finishing of furniture facades, furniture parts and interior doors.

The range of products we offer is widely represented by a variety of designs, degree of gloss and relief embossing, allows you to satisfy individual preferences and captivates with the first-class quality of the material.

A high-quality finishing recipe – 3D thermoformable films are excellent for processing workpieces even with very small radii.

The quality of 3D thermoformed furniture films based on rigid PVC is ideal for membrane pressing. Due to their excellent elasticity and hiding power, 3D rigid PVC films are increasingly used to refine the surfaces of doors and cabinets, tables, work surfaces, as well as furniture elements and panels.

Variety of designs and materials

8th Degree is a wide selection of decorative cladding materials for the production of furniture, doors, wall panels and interior parts. Together with our customers and partners, we are constantly expanding our existing range of films and also developing individual solutions for completely harmonious designs - from kitchen surfaces to wall coverings.

What to combine with a glossy set?

Whatever you say, a glossy set, regardless of color, will stand out and attract attention.
Glossy MDF painting is undoubtedly an accent in the interior. It is better to surround it with discreet matte surfaces. This applies to the tabletop - it will also be more convenient, but it is especially important for the ceiling and floors.

A glossy set in combination with a glossy ceiling will not look as impressive as gloss on a matte background. The combined facades look interesting - the top is glossy and the bottom is matte. Or, for example, all horizontal surfaces are dark matte, and vertical surfaces are bright gloss.

The combination of a glossy finish with natural materials or their imitation looks interesting. Wooden details or a stone countertop will contrast very favorably with the brightness of the gloss.

Gloss MDF painting is a suitable choice for any modern design. It doesn’t matter whether it’s high-tech, loft, modern or fusion. By choosing the right color you can easily fit such furniture into the interior.

24-95080-9734-2-350, Matera Steel, PVC film for MDF facades

Impeccable optical characteristics of films - PVC films are produced according to modern recipes.

Exceptional wear resistance, operational and technological properties.

Strict European quality standards - all films do not contain plasticizers, heavy metals, or other impurities hazardous to health.

Versatile possibilities for high-quality finishing of furniture facades, furniture parts and interior doors.

A high-quality finishing recipe – 3D thermoformable films are excellent for processing workpieces even with very small radii.

Variety of designs and materials

Types of primers

Acrylics are the most versatile. Suitable for working with wood, chipboard, metal and other surfaces, increasing adhesion to paint or wallpaper. They dry in about five hours and have almost no odor, so they can be used indoors.

Alkyd

create a durable film on the surface that is resistant to environmental influences. Suitable for indoor and outdoor use. Can be applied to wood, metal, plastic and even glass.

Polymers are durable, resistant to mechanical damage, ultraviolet radiation and temperature changes. Typically used for processing concrete, brickwork, plasterboard, cement-sand, lime-sand and cement-lime plasters.

Glypthal

Suitable for work in dry rooms. They are applied to metal and protect it from corrosion. They will take about a day to harden.

Quartz

called concrete contact. They are used to improve the adhesion of plaster, putty or tile adhesive to monolithic concrete and other surfaces with low absorbency.

Perchlorovinyl, phenolic and polystyrene

primers are not used in residential areas due to toxic components. But they dry quickly and are suitable for most surfaces.

DIRECTIONS FOR USE

Application conditions.

Base temperature: +5ºC-+25ºC and should be 3ºC above the dew point.
Relative air humidity is not higher than 80%.

Procedure for working with filler.

Open the packaging with components A and B. Pour component B from the container into a container with component A. Mix using a mechanical mixing device (such as a drill) for 5 minutes, pour the composition into a clean container and mix again for 5 minutes. Allow the composition to sit for 10 minutes and immediately begin applying the material.

The foam filler is applied to the surface with a spatula, followed by leveling with a short-pile velor roller.

Equipment cleaning products.

To clean the instrument, use as a solvent: butyl acetate, xylene, solvent, acetone or mixtures thereof.

Precautions when working with foam filler.

When working, use protective clothing, gloves and safety glasses.

Do not use faulty or ungrounded electrical equipment.

Smoking and eating while working with the material is prohibited.

If the material gets into your eyes, rinse them with plenty of water and immediately consult a doctor. If it gets on skin, wash it off with plenty of soap and water.

How and with what to prime wood

For those who are superficially familiar with wood processing technology, and for the first time are going to build a wooden fence with their own hands, sheathe walls or, for example, make a crib, the following information will be useful.

What wood needs priming?

If you are doing interior work, want to preserve the natural beauty and structure of the wood and are not going to paint it, there is no need for priming. It is enough to treat it with impregnation - transparent or tinted - to simply protect it from changes in humidity, mold, bugs and achieve color harmony with other interior details.

But in the following cases, this step absolutely cannot be skipped:

If wooden structures will “work” in the open air. They are more exposed to changes in temperature and humidity, as well as to rot and insects. These are fences, entrance doors, windows, roofing elements, outer cladding of the building, etc.;

If wet or unheated rooms are finished with wood - bathrooms, balconies, terraces, verandas;
If internal structures are in contact with external walls;
If there are noticeable defects on the surface that need to be sealed with putty;
If the wooden surface, regardless of its purpose and operating conditions, is intended for painting or varnishing.

Types of primer for wood

Before priming wood before painting, you need to choose the right composition that meets your requirements. There aren't many of them.

Type of primer	Properties	Purpose	Note
Alkyd	They strengthen the pores of wood, reduce the absorbency of the treated surface, and prevent swelling of the fibers.	Designed for initial application on fresh, untreated wood, chipboard, fiberboard.	They contain organic solvents, so they are not recommended for use in residential areas.
Acrylic	They have the same properties.	Preparation of a wooden base for painting with water-based, alkyd, latex paints.	They dry quickly, can be diluted with water, and are safe for health.
Antiseptic	Prevents and eliminates fungal infections and preserves wood.	Used to protect structures operated in difficult conditions.	Unpainted surfaces should be treated every 3-5 years.
Shellac	Neutralizes the effect of resins that can discolor the finish coat.	Used for coniferous wood and knot processing.

Note! When working with primers containing toxic insecticidal or fungicidal additives, safety rules must be followed.

One-component mixtures

The primer contains polyurethane and various solvents. However, depending on the base material and its location (inside or outside), special components may be added to the mixture. Polyurethane primer can be one- or two-component.

The former consist of a base substance and a solvent. Suitable one-component polyurethane primer for MDF, concrete walls, wooden surfaces. They effectively strengthen the base, allow it to be leveled and increase adhesion to the finish coating.