Primer for oil paint - how to apply a new composition without removing the old layer. Difference between primer and paint

What is the difference between primer and paint? Is it possible to prime paint if, for some reason, stripping it is problematic? How to prepare a painted surface for further finishing? Let's try to find the answers together.

Meet: primer

Primer compositions differ from coloring ones in several ways:

• Pigments are either absent or contained in small quantities. In addition, the cheapest dyes are used.

Please note: the exception is the so-called enamel primers. For example, paint-primer for metal AU-1417 R can serve as both a base layer for further painting and an independent coating.

• On the contrary, maximum attention is paid to adhesive qualities. The soils adhere perfectly to any surface; some compositions are not limited to this: they contain compounds that transform the base for better adhesion or acquisition of any additional qualities.

Thus, strengthening soils serve to increase the strength of loose surfaces, and phosphating soils transform a thin film of metal into its stable compound with phosphorus.

Despite the difference in functionality, the composition of primers and paints often differs slightly. Thus, the alkyd primer GF-021 is based on the same binder (varnish GF-01) that is used to prepare enamels of the PF line; The surface for oil paints is primed with drying oil, which also serves to dilute these paints.

Preparation for painting

Traditional option

What operations should precede painting a base covered with old paint?

1. Cleaning the paintwork.
2. Puttying to eliminate minor defects.
3. Grinding a surface to make it rough.
4. Application of primer selected for surface type and composition new paint.

Let us clarify: the primer-paint, as we remember, is tinted if necessary desired color and simply applied to the base in 2-4 layers with intermediate drying.

However, in some cases, removing old paint is problematic.

List possible reasons quite extensive:

• Limited resistance of the base to washes.
• Insignificant heat resistance, which does not allow using a hair dryer to soften the old coating.
• Low mechanical strength of the base, which does not allow old paint to be removed with a spatula or sanding.
• Finally, just a larger surface area to paint. Imagine that you have to paint a hundred or two square meters of surface alone. Here you can’t help but think: is it worth spending several days, or even weeks of work on cleaning it?

Priming on paint

Fortunately, thanks to modern primer compositions, you can make your life much easier.

Primer by old paint It is quite possible if several conditions are met:

1. The coating is not glossy. If so, you will still have to spend time rough sanding it.
2. Old paint does not peel off. Where its layer comes off, it must be cleaned.

In addition: if the new paint is of the same type as the old one, intermediate priming is generally not necessary. Acrylic water-dispersion paints fit perfectly onto acrylic and acrylic-latex paints; Oil paint can be painted over oil paint, alkyd over alkyd, and so on.

Primers for old paints are versatile: they become an intermediate layer between the old and new coatings, having equally high adhesion to both of them.

Study of samples

Let's study the consumer qualities of several soils of the type we are discussing.

VD-AK-0301

Here is a primer for acrylic paint, which provides priming not only of absorbent substrates, but also of old paintwork.

What information about this primer can be gleaned from the description provided by the manufacturer and sellers?

• Compatibility with previously applied coatings of PF, NTs and oil paints is guaranteed. Full list is hidden behind the laconic postscript “etc.”
• After drying, the soil forms a uniform film of milky white color.
• Consumption is approximately 200 g/m2.
• Dilution with water is allowed (no more than 7%).
• The soil can withstand freezing down to -40C (no more than a month) or five cycles of freezing and thawing.
• Touch-drying time is no more than two hours. Complete drying of the soil applied in one layer, with room temperature takes no more than a day.

Neomid primer for old paint

This composition is more universal: according to the manufacturer, Neomid is a primer for water-based paint and any enamels based on organic solvents.

• The primer includes an aqueous dispersion of acrylates, a polymer binder (unfortunately, it chemical composition not specified), mineral filler, pigment and additives that improve adhesion.
• Dilution with water is acceptable (up to 10%).
• Drying at room temperature is slightly faster: it only takes an hour.
• Unlike VD-AK-0301, Neomid primer is recommended to be applied in two layers with intermediate drying.

Optilux

And this primer is universal: a primer is acceptable for oil paint, enamels of the PF and NC types, various varnishes and concrete foundations for any type of paint and varnish coatings, putty and wallpaper.

• The primer is based on the same aqueous dispersion of acrylic resins with the addition of mineral filler, pigments and special polymers to increase adhesive properties.
• Consumption - 100-200 grams per square meter depending on the type of base.
• Drying one layer at room temperature takes no more than an hour.
• The composition can withstand five cycles of freezing and thawing.
• The manufacturer especially emphasizes that its composition does not require pre-grinding of the previously painted surface before application.
• The wholesale price of primer is about 40 rubles per kilogram.

The representativeness of the sample is small, but it makes it possible to make some generalizations:

1. Any primer for oil paint or enamels based on organic solvents - acrylic water-dispersion.
2. If so, any work is possible only at positive temperatures.
3. To store materials of this type, it is strongly recommended to use rooms with a stable positive temperature.

Preparing a painted surface for painting

How to prepare and prime a previously painted wall or ceiling with your own hands?

The instructions are approximately the same for all types of soil.

1. The peeling areas of the coating are removed with a spatula.
2. The surface is sanded with coarse sandpaper or a sanding grid of numbers 80-100. It is acceptable to use a wire brush or suitable attachment for hand power tools. The goal is to leave it on the surface maximum amount minor scratches, promoting soil adhesion.

Please note: it is better not to neglect this operation even if the manufacturer assures that grinding can be done without. Glossy surface always provides worse adhesion to the next surface.

1. Irregularities remaining from peeling paint are filled with putty compatible with the base (concrete, wood, etc.).

1. The putty areas are sanded again.
2. The primer is applied with a brush or roller. A spray gun is not suitable in this case: all the primers we examined have a consistency that is too thick for pneumatic spraying.

Wood is a rather capricious material. She demands correct processing. To give wood the necessary performance qualities, various primers are used. They protect the material from various adverse influences.

Various are available for sale wood primer for painting. It is characterized by a number of features. When choosing, you must take into account expert advice. They will tell you which primer is best to purchase for repair work.

Primer properties

is a special construction composition. It is sold in various containers. When applied to the surface it leaves a thin film. It prevents the processes of wood rotting, the appearance of fungi and bacteria on it.

It should be noted that wood is a natural material that has high moisture absorption. This means that when applying various compositions to its surface, their consumption increases significantly. The primer helps prevent this negative phenomenon. It significantly reduces the moisture absorption of wood.

In some cases, new paint is applied to old layer. This can only be done if the material used is the same in composition as that found on the wood. For example, old oil paint can be immediately coated with the same coating. However, the shade of the new layer may change slightly. To prevent this from happening, use a special primer.

Primer properties

Primer for wood for painting with acrylic paints, oil and other compositions has a number of main effects. She disinfects natural material. Moreover, even with high humidity, mold and mildew do not appear on the surface.

Primer is also used to strengthen the surface of the material. This is especially important for wood that has been in use for many years and needs restoration. The base is impregnated with special resins. At the same time, its moisture absorption is significantly reduced. Consumption finishing materials, as well as the costs of repairs, are significantly reduced.

Wood contains a special coloring pigment - tannin. It may appear on the surface of the paint. In this case, the finish looks untidy. Primer compounds trap tannin within the wood, preventing it from reaching the paint.

Functional properties of the primer

Primers available for sale can be divided into several categories. In terms of functionality, the tools can be of three main types. The first category includes strengthening compounds. They are called deep penetration primer for wood for painting. These are universal impregnations that allow you to strengthen wood before subsequent finishing. Such compositions are used not only for wood, but also for concrete and brick surfaces.

To the second large group include antiseptic compounds. They eliminate unwanted microflora that is already present in the wood. In the future, fungi and bacteria will also not be able to develop on surfaces treated with antiseptic.

The third category of products includes hydrophobic primers. They protect the texture of the material from excess moisture. These primers are used for wooden facades, various objects (for example, benches), which long time are outside the premises.

Compound

Depending on the components that make up the product, there are different kinds primers. They differ performance characteristics.

Suitable not only for wood, but also for metal. Well absorbed. They are suitable for any type of paint. Acrylic primers dry quickly (1-4 hours) and do not have an unpleasant odor.

Silicone acrylic primers significantly reduce water absorption of the material. The surface after treatment is characterized by a stable level of humidity.

Alkyd primers are used before applying paint on a similar base. This composition contains a lot of solvent, so the surface dries quickly. Such compositions are well suited for surfaces with an old layer of paint.

Polyvinyl acetate primer dries quickly. It is treated on top with PVA glue.

Polyurethane products are also on sale. They are used to impregnate parquet. If you need to smooth the surface of the wood, you need to use shellac primers.

Price Price of wood primer for painting

may vary significantly depending on its type and manufacturer. Thus, universal compositions of deep penetration can be purchased at a price of 600-800 rubles. for 10 l. At the same time, water-dispersed products in this category are much cheaper. A 10 liter canister can be purchased for 200 rubles. It is used for interior work. Oil formulations that belong to the universal category can be purchased for 800-900 rubles. (capacity 0.9 l). These are products presented in the form of paint with big amount

Adhesive primers cost about 850-950 rubles. for a capacity of 0.9 l. They are made on an alkyd base. Suitable for applying primer to a layer of old paint.

Deep penetration primers are somewhat cheaper. A 10 liter capacity can be purchased for 1100-1200 rubles. Costs may vary significantly between brands.

Main characteristics

In order to choose the right primer composition in accordance with the needs of the material, it is necessary to consider the main qualities of each product. Acrylic varieties are suitable not only for wood, but also for chipboard, fiberboard, brick and plaster. They dry in 2-4 hours.

Alkyd primer for wood for painting dries within 10-14 hours. It is also suitable for metal surfaces.

Polyurethane varieties differ long period drying. It takes them a day to become ready for further finishing. Such compositions are suitable for both absorbent and non-absorbent surfaces. Even if you have to work in very dusty conditions, polyurethane primers provide high-quality adhesion of the paint to the base.

In addition to wood, silicone compounds are also suitable for concrete, plaster, and limestone. Such soils dry out in 4-5 hours.

In the process of painting interior surfaces, the main emphasis is on quality training grounds. The final result of painting depends on this. A considerable problem is the removal of the old paintwork, after which a primer is applied to the surface, and then the new paint itself.

However, if the old paintwork has no special defects, retains reliable adhesion, the surface is not riddled with cracks, and the paint has a quite presentable appearance; priming can also be done over the old coating. That's why many people are interested in how reasonable it is to prime old paint.

Do I need to prime the wall before painting?

Someone might argue that in this state of affairs it is not at all necessary to use a primer, and new paint can be applied over the old coating. But it is not so. In any case, so that between the new paint and the base there is a good adhesion, a primer layer is required. In addition, the soil allows you to reduce the absorbency of the walls, thereby reducing consumption. paint and varnish material. Additionally, the primer acts as an antiseptic and also speeds up the drying of the paint. So, in order to use paint better and more economically, a primer is a must. And a primer for wallpaper should also be done, and not just a primer for paint.

Applying new paint to old paint is only possible if similar compositions are used. For example, acrylic paint can be placed on the same acrylic or latex acrylic paint. The same situation is observed in the case of oil or alkyd paint. But these compositions cannot be mixed with each other without an intermediate layer of primer.

If you plan to prime a previously painted surface, remember that it should not be glossy. If this is the case, then in this case you will have to roughly sand the old coating. Also, any areas where paint is peeling must be completely cleaned of the old layer.

Before applying the primer, it is necessary to clean the surface, removing all dirt layers. To do this, a damp sponge and a solution based on household chemicals. After this, the surface should dry completely.

Padding

1. Preparation and application of primer is carried out in the following order:
2. Mix the composition thoroughly. If this is not done, the surface will not be uniform.
3. Primer compositions have a thick consistency. To make it easier to apply the primer, it is recommended to slightly dilute it with water. However, the proportion of liquid should not exceed 10 percent.
4. Pour the prepared solution into a container. It is best to use a special flat painting tray.
5. We wet the roller in the primer mixture and squeeze it out on a special platform (if there is a painting tray).
6. Apply primer to the surface using a roller. The solution must be applied evenly. The layer should not be too thick. We try to avoid drips. To do this, carefully rub the composition over the surface.
7. Places that are difficult to reach with a roller are treated with a brush.
8. To ensure proper adhesion, after the first layer has dried, apply the second. Optimal temperature for soil drying is 20-23 degrees above zero, and the indicator relative humidity should be between 70-80 percent. Under such conditions, the surface will dry in about an hour.
9. The work is completed, all that remains is to rinse the tool in water.

Attention! If the primer solution gets into your eyes, rinse them immediately under running water. Moreover, washing should be carried out for 10-15 minutes.

When the primer has dried, you can begin painting the surface. However, an explanation is necessary here: the conditional and final drying times differ for different manufacturers. Specific numbers can be found by reading the instructions from the manufacturer. You should also make allowances for the characteristics environment(humidity and air temperature). When the primer has dried, painting or wallpapering can begin.

Sooner or later there comes a time when the premises in use require repairs. Most often, cosmetic repairs are needed, but major repairs are also possible. It all depends on the degree of deterioration of the building and the planned financial investments. Cosmetic repair is a minor job in minimum terms and at relatively low cost. Overhaul refers to a costly and significant alteration to a building. It takes a long time and is complex; many different factors and building materials are involved.

When redecorating, paint and primer are almost always used, and inexperienced people wonder: what is it, and what is the difference between them?

First, it’s worth understanding what these materials are and how they are used.

Dye

Construction paint is a suspension that is applied to various surfaces prepared in advance for painting. Paint has two main purposes:

Giving the surface the desired color. In modern times, the choice of paint colors is huge. Everyone can find the right color for the required surface, it all depends on the desire of the buyer. Painting in the right colors can change the interior beyond recognition and give it beauty. Moreover, having a huge selection of colors, you can combine different combinations of colors, and good selection the result will be amazing.

Protecting the surface from environmental influences. Since paint is last layer, which is applied to the surface, then it must have strong protective factors. Manufacturers are constantly improving their products to achieve better protection. Various paints Designed for application indoors or outdoors.

Paint that is used outside must be resistant to rain, snow, hail, impact sun rays and temperature changes. When used indoors, the wear and aging characteristics must be at a level, the paint must be washable. There are also types of paint that protect metal constructions from corrosion and many others.

There are many types of paints and each has its own characteristics. For example:

1. PVA-based dispersions.
2. Silicate paints.
3. Paints based on organosilicon varnish and coumaron-indene resin.
4. Nitro enamels.
5. Water-based.
6. Oil paints, etc.

Primer is a composition that is applied to the surface as a starting layer for subsequent work. The primer is a material for pre-treatment. It has the following purposes:

Surface leveling. When repairing, uneven surfaces are very common. It is impossible to apply a subsequent layer on them, and in this case, workers resort to using a primer. With its help, all defects are removed and the surface is made ideal for subsequent work. No matter how uneven the surface is, after correct and competent application of the primer it becomes smooth and beautiful. It is also worth mentioning that the primer is usually applied in several layers.

Improved adhesion of the surface to the subsequent layer. Regardless of the material, be it a metal surface, concrete or wood, it is necessary to treat it with a primer. The principle of operation of the primer is deep penetration into the surface layer and improved adhesion. It also prevents damage to the initial surface during further work. Also, when applying the primer, small particles of concrete or brick dust, plaster, putty and other construction impurities that will interfere with further work are removed.

Reducing the consumption of subsequent materials during application(plaster, glue, paint, etc.)
Primers, like paints, have different types with different purposes:

• Alkyd primers.
• Epoxy.
• Silicate.
• Shellac.
• Polyvinyl acetate, etc.

And so, having examined both building materials, we can say with confidence that they have a lot in common:

1. Both materials are used towards the end of the work.
2. A similar method of application to the surface.
3. Both paint and primer must dry after use.
4. Both materials have protective properties.
5. There are different types of paints and primers with their own special properties.

Differences between paint and primer

The main difference is that the primer is the “foundation” for the application of various final materials, such as wallpaper, whitewash and paint.

Unscrupulous or inexperienced builders immediately proceed to painting surfaces without first treating them with a primer, and the result leaves much to be desired. As a result, the paint begins to come off, looks uneven, and then remains on the starting surface. Even if the walls are initially beautiful and smooth, you should not neglect applying a layer of primer, so as not to regret saving later. The saying “The miser pays twice” fits well in this case.

The primer and paint are a complete system in which each performs its own functions necessary for good repair which were given above.

As a result, we can say with confidence that paint and primer are different building materials, and very necessary. For the perfect cosmetic repairs It’s worth combining these materials correctly and not making a mistake in your choice.

The primer composition, naturally, differs from the coloring composition both in its components and functionality. In most cases, the primer contains no coloring pigments, or they are present in very small quantities. And if there is, then the dyes in it are the cheapest.

Paint is a decoration and protection for the surface. But before applying a layer of paint, the surface is prepared for this procedure by priming - without this, the durability and strength of the paint layer can be called into question.

For example, if metal surface, directly cover the roof of the gazebo with paint, after a few months the paint will easily begin to crack. And then expect delamination and entire pieces of paint coming off. For chipboard, MDF, and plywood, a primer for painting is also necessary.

Simply put, primer increases the effectiveness of the paint, ensuring its durability and strength.

Priming walls before painting (video)

Other functions

Primer is preparatory stage before painting, which, as mentioned above, increases the effectiveness of the paint layer.

But the primer also has other functions:

• It strengthens the base of the surface;
• It reduces the absorbency of the surface, which is important for those walls or coatings that especially absorb moisture;
• It allows you to reduce the amount of paint used;
• It serves as protection against emerging stains;
• Protects the base from moisture;
• Finally, it serves as protection against fungus (for this you need a primer with fungicidal additives).

If the base you are painting is quite loose, or you have to work in a room with high humidity, the use of a primer is not discussed.

How the process works

The first thing to consider is the conditions in which the primer is carried out. The air temperature should be no less than plus five, but no more than plus thirty. And air humidity should be no more than 75%.

You need to prime using the following tools: stepladder, extension handle, tray.

How to apply primer:

1. First, you can and should wash off the lime whitewash from the wall; this is usually done with a roller and water. If there is wallpaper on the wall, it should be torn off. Small particles that do not come off immediately are removed with a wet cloth and a spatula.
2. Dilute the primer according to the instructions, which are always on the package.
3. Stir the resulting solution very well; this can be done with a mixer on a drill.
4. Using a roller or brush (whichever is more convenient for you), evenly coat the wall with the primer solution so that there are no smudges or stains left on the surface.
5. Drying time for the first layer of primer is two to three hours.
6. After this, apply a second layer of primer to the wall, which takes about the same amount of time to dry. Two layers are usually enough.

The process is simple, but requires a little clarification. How long the primer takes to dry depends on conditions, temperature and humidity. Never dilute the entire primer mixture at once; usually only part of the primer mixture is sufficient.

All tools must be washed and dried immediately after work.

Regarding personal protection, work with primer in good rubber gloves, special safety glasses and, of course, a hat.

Special primer for old paint

We can say something separately about the VD-AK-0301 primer for old paint. This special kind primer, which is suitable for pre-treatment of surfaces that were previously painted with oil paint. It is used before coating with water-dispersion paints.

Why do you need a primer on old paint:

• It forms a film on the surface of the old coating, which improves adhesion with water-dispersion paints;
• Used for both exterior and interior finishing work;
• It facilitates the process of applying water-dispersion paint;
• As a result, you have a smooth, translucent, milky matte surface.

It takes a day for such a primer to dry completely, but the peel-off time will be two hours. It is applied with a roller or brush in one layer.

The nuances of applying old paint

Theoretically, it can be applied, but only if you are sure that the paint is applied in only one layer. And, of course, if you know that the previous surface treatment along with the primer was carried out correctly.

But if you don’t know this, or are not sure about it, then there is a high risk that the primer will cool down along with the old paint. For any repair, experts advise removing the old coating - do you then apply water-based paint, apply a primer on metal or concrete, will you be doing putty, etc. Removing the old coating means removing the risks of unsuccessful repairs.

Primer for oil paint for putty

If you plan to do putty, then it is preferable to use a quartz primer. Its small particles will provide better adhesion to the putty. And this is a good solution, because even if there are paint particles left on the wall, the primer will penetrate perfectly into the wall layer.

After applying the primer and drying, check the quality of the surface - sometimes cracks appear on it. If this is the case, you can use a special mesh. The putty is applied to the wall with a wide spatula, making sure to cover up all the imperfections and cracks.

Can it be mixed with paint?

There are several opinions on this matter, among them the most contradictory ones can be found.

How to make a primer with your own hands (video)

Primer and paint are two compositions that are usually used sequentially. In some cases they are mixed, but usually the primer precedes painting, enhancing the quality of the entire finish.