Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting work: painting walls, metal products etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
Compound
In fact, the only similarity is that both are paints. They are completely different in composition.
The alkyd type can be called a more modernized version of oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Alkyd paints consist of polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
Basic properties
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy surface layer paints. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sun rays, that is, it does not fade, does not turn yellow and does not acquire a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully performs its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming the acrylic film is compensated by more high level resistance to mechanical stress (deformation, scratches).
- Decorative properties.
8. Is it possible to apply acrylic paint to alkyd paint and vice versa?
Alkyd compositions are distinguished by a more diverse range of shades and undertones, as well as generally more bright colors. On the other hand, acrylic paint lasts longer and does not require regular updating.
Are acrylic and alkyd paints compatible?
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither one nor the other is recommended, especially if the painting of the base occurred relatively recently or we are talking about metal surface. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply upper layer paint should only be used after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
Acrylic paints and oily type used for finishing surfaces from the outside, as well as inside. In some cases, it is necessary to cover with acrylic a surface that has been painted with oil paint. To find out whether one paint can be coated with another, you need to consider the properties of each material.
Oil paint
Some time ago, oil paints were actively used to decorate surfaces inside and outside. But they were replaced by a new, more universal material, acrylic paints.
The oil material is made from drying oil or a similar product, which is mixed with pigments mineral type. The paint is obtained by grinding all components to a homogeneous composition. IN modern renovation oil paint is used very rarely. But in some cases it is advisable to use it as a cost-saving option for coloring large premises, since its cost is lower than other materials. The main advantage of oil-based paints is their low cost. Such materials are resistant to moisture, oils have reliable protection wooden, and concrete materials. Oil-based paints also prevent rust on metal surfaces.
This material has its drawbacks, which makes working with paint not very convenient. There are not too many colors, almost a dozen, so it is difficult to create a specific design and give originality to the surface.
Also, the paint needs annual renewal, that is, it wears out quickly, it takes additional expenses. If the surface is not renewed in a timely manner, the material may peel off in large pieces. During application, a strong odor appears, so work should be done in a well-ventilated area. When dry, the surface releases toxic elements, so it is best not to spend time in a painted room. A negative quality is the long drying time of such material, almost two days.
On oil surface You can apply acrylic paint, it will not be difficult.
Acrylic paints
Compared to oil compositions, acrylic paints have clear advantages. Acrylic compositions are environmentally friendly and do not emit toxic substances, since they do not contain organic solvents.
The basis of this material is water, due to this there is practically no odor during application. The material also has a large number of colors and shades, this allows you to make the surface original. The required color can be ordered at hardware store, and it will be done on the spot. The acrylic composition is highly resistant to humidity, ultraviolet rays, and temperature changes, and also has good vapor permeability. Thus, acrylic paint is used to decorate the room inside and outside. The painted surface dries quickly, in just a couple of hours. If we compare oil- and acrylic-based paints, the latter are considered more durable and wear-resistant. Such compositions are considered universal and are used to create a variety of interiors.
Can you paint with acrylic paint over oil paint?
Typically, experts do not recommend applying acrylic paint to an oil coating that is too old, since the materials do not adhere well to each other. But such work is allowed provided that the surface is thoroughly prepared. Surface preparation work begins with sanding the previous coating, using fine-grained sandpaper.
After grinding, the surface is thoroughly cleaned of dirt and dust that has formed as a result of work; a vacuum cleaner can be used for this. Then the surface is degreased and left to dry. The dry surface is covered with 2 layers of acrylic-based solution. But thorough preparatory work They don’t talk about high-quality application of acrylic paint on an oil surface. To get the result, you must use a thick acrylic composition; when diluted with water, the proportions should not exceed 1 to 1.
If a spray bottle is used as the application tool, a suitable thinner must be added. The gloss or dullness of the surface depends on the type of this substance. Sometimes oil paint eats into the surface, especially if it is used too much. long time, then it is impossible to remove it. In this case, special paints are used that are characterized by high adhesion; they are able to efficiently paint even a very greasy surface.
Technology of applying acrylic paint based on oil composition
- First, the surface is sanded, all dust is removed using a vacuum cleaner.
- Then they are treated with a primer. And leave until completely dry.
- The acrylic composition is applied with a brush or spray; in the latter case, special thinners are used.
- Start applying paint from the corners of the surface to the middle or from top to bottom. After completely covering the walls or ceiling, leave time to dry, usually a couple of hours; there are paints that dry faster.
Basic rules when applying acrylic paint to an oil composition
- To ensure a high-quality painted surface, it must be well prepared. The main oil layer of paint is removed by sanding, and then the dust is removed.
- All dirt must be cleaned off so that the acrylic composition lays down in an even layer.
The difference between alkyd paint and acrylic paint
- In too advanced cases. If oil has become embedded in a wooden or other surface, use special paints with a high adhesion rate.
- Surface sanding can be done with fine-grit sandpaper or special grinder. In some cases, a drill and a special attachment are used; you must act carefully so as not to damage the surface.
- Degreasing is a must, otherwise new line-up will not fit well on the previous surface.
- To ensure high-quality adhesion of the paint to the previous surface, the acrylic composition must have a thick consistency.
When choosing a paint composition, it is necessary to study its properties, all positive and negative qualities, since the service life of the coating and its reliability depend on this. Before purchasing material, you need to consider what kind of coloring will be done, primary or secondary. In the second option, a surface that has already been previously treated with other compounds is coated.
It is especially taken into account when the walls are painted with oil paint, these are the consequences of old repairs. Typically, oil paint was used for kitchens or bathrooms. When choosing a modern acrylic-based paint, you need to figure out what to do with the old finish, namely the oil composition. This article describes all the advantages and disadvantages of oil and acrylic paints.
It is usually not recommended to coat oil paint with an acrylic composition, but it is possible if you resort to careful surface preparation. The old material is partially cleaned off by sanding with sandpaper, primed, and covered with acrylic paint.
Alkyd primer and acrylic paint
A primer is applied to the surface before painting to provide protection to the surface and to improve the adhesion of the paint that will be applied over the primer. The deeper the soil penetrates into the surface being treated, the better the paint will stick to it. A primer for metal, for example, is a prerequisite for high-quality painting of metal surfaces.
When applied, the primer fills the pores of the surface and binds small particles of foreign matter (for example, dust), thereby preparing it for applying paint or other paint and varnish materials.
What is the difference between alkyd paint and acrylic paint?
Any primer, be it an acrylic primer for wallpaper or a primer for metal, can significantly reduce the consumption of expensive materials. The savings are especially noticeable when priming large areas.
Another advantage of using a primer is that the primer material slows down the penetration of substances from the composition of the next layer, which helps to dry the painted surface evenly. Uniform drying, in turn, improves the quality of painting, eliminating cracks and warping on the surface being treated.
Currently, compositions of this type, whether it is a water-dispersion primer or soil deep penetration, are indispensable materials for interior or exterior renovation of residential buildings and production premises. There are many types of primer coatings (acrylic primer for wood, alkyd primers, strengthening and bonding compounds, materials for priming metals) intended for different types surfaces and materials of subsequent layers.
Substances included in the primer coating should not react with substances from paints and varnishes that will be applied over the primer. Therefore, before starting repairs, it is necessary to find out what type of primer is suitable for a particular paint and surface. For example, a deep-penetrating universal acrylic primer works well on plaster, brick or concrete. Putty, plaster and other finishing materials will subsequently work well on compositions of this type.
Primer compounds are also useful if you need to treat a loose, crumbling surface. For repair work With such surfaces, deep penetration compounds have been developed that can make the surface denser and prepare it for painting or finishing. The cost of deep penetration primer is quite high, but for quality repairs she is sometimes irreplaceable.
If you are going to carry out repairs in a room with high humidity, then pay attention to such a material as the universal acrylic primer Bulls Eye 1-2-3 Primer Sealer Stain-Killer. This coating contains antiseptics that prevent the spread of mold and fungi. This acrylic primer is perfect for treating surfaces made of various materials- concrete, brick, plasterboard, chipboard, wood, metal and many others.
Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting projects: painting walls, metalwork, etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
Compound
In fact, the only similarity is that both are paints. They are completely different in composition.
The alkyd type can be called a more modernized version of oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Alkyd paints consist of polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
Basic properties
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy the surface layer of paint. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sunlight, that is, it does not fade, turn yellow or take on a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully performs its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming an acrylic film is compensated by a higher level of resistance to mechanical stress (deformation, scratches).
- Decorative properties. Alkyd compositions are distinguished by a more diverse range of shades and halftones, as well as generally brighter colors. On the other hand, acrylic paint lasts longer and does not require regular updating.
Are acrylic and alkyd paints compatible?
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither of these is recommended, especially if the substrate was painted relatively recently or if the surface is metal. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply the top coat of paint only after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
There are several types of acrylic paints:
a) acrylic paints on water based(interior or facade paints);
b) two-component acrylic enamels (car acrylic paints in a can).
They contain two components: paint and hardener, and polymerize due to chemical reaction with a hardener, and this reaction is irreversible.
c) one-component acrylic enamels (used in aerosols). They dry in air due to the evaporation of solvents.
Acrylic two-component paints cannot be applied to alkyd and acrylic one-component paints, as they behave aggressively towards the latter. It is possible to apply alkyd and one-component acrylic paints to two-component paints, since the polymerization reaction is irreversible and the coating is durable.
Aerosol paints use a one-component base.
All aerosols dry in air due to the evaporation of solvents. Therefore, it is possible to combine the application of acrylic and alkyd aerosol paints. But you need to apply the paint no later than 30 minutes after applying the last layer of paint (acrylic or alkyd).
8. Is it possible to apply acrylic paint to alkyd paint and vice versa?
Also, the solvent plays an important role. If the solvent is aggressive, it can dissolve alkyd paint. Typically, more aggressive solvents are found in acrylic one-component paints. Therefore, when applying acrylic one-component paint over alkyd paint, you need to be careful and first make sure that the coating is not adversely affected.
In the case of applying alkyd one-component paint to acrylic, subject to temporary recommendations (no later than 30 minutes after applying the last layer of paint), there is no reason to be afraid, since solvents in alkyd one-component paints are less aggressive.
Repairing painted surfaces is an inevitable process. Even if the finishing was previously done competently and with high-quality materials.
Before repainting the walls, you need to make sure that the new and old coating will be compatible.
At the moment, there are many ways to remove old paint.
- Mechanical methods. Acrylic enamel and acrylic paint or other coating are removed with sharp objects or power tools, such as a drill with an attachment.
- Thermal methods. In this case, the paint is softened, for example, with a hair dryer, and then removed.
- Chemical methods. The finish is removed using a variety of removers.
However, the process of removing the old coating is long and labor-intensive. And the price is quite high, especially if you need to remove paint from a large area or complex surfaces. Based on this, many of us prefer to apply new finishing directly onto the old one. At the same time, the question of compatibility of coatings often arises.
In this article we will talk about whether acrylic paint can be applied to enamel and vice versa. However, first we will understand the basic concepts.
Types of paints and varnishes
The composition of paints and varnishes includes binders, fillers, pigments, solvents/thinners and additives. In order to competently use paint and varnish materials during repairs, you need to know exactly their composition.
Main Components
Oil paints based on drying oil.
All paints are divided according to the type of binder used and the type of solvent.
- The binder determines the main qualities of the paint, the service life of the coating and the speed of its drying. There are 4 common types of binders used for paints and varnishes: alkyd and epoxy resins, oil-based (on drying oil), latex, acrylic polymers.
- Solvent components are divided into solvents and diluents.. The former reduce the fluidity and viscosity of the material. Thinners only reduce the viscosity of the paint.
- To improve the characteristics of paints and varnishes, additives are added to their composition.: stabilizers, emulsifiers, fungicides, antiseptics, etc.
- Special paints belong to a separate category. This anti-corrosion coatings, for example, Zinga conductive paint. Analogs with antiseptic properties that protect the base from mold and rot. Compositions for removing small defects (irregularities, scratches, cracks), etc.
Oil and enamel compositions
The photo shows acrylic enamel.
Materials based on alkyd and acrylic resins include oil and enamel paints.
They are suitable for painting metal, wood and plastered surfaces.
After drying, they are non-toxic, light and moisture resistant.
- Oil paints are produced on the basis of drying oil. White Spirit, gasoline, turpentine or solvent naphtha are used as diluents. The compositions are not expensive, but they take a long time (up to several days) to dry. The main disadvantage is that the coating turns yellow over time.
- Varnish is added to enamel compositions as a binder. It gives the coating gloss and aesthetics. The instructions recommend using such paints for external and internal finishing works for metal, wood, concrete, plaster.
Differences between alkyd and acrylic paints
Enamels are moisture and light resistant. They also have anti-corrosion resistance.
Emulsion and dispersion materials
Water-dispersed composition.
Such paints are diluted, but not soluble with water. In them, the binder and pigment particles are distributed in a liquid medium, creating a stable emulsion.
When the coating dries, it is not washed away by water.
- Emulsion compositions are economical, environmentally friendly and fire safe.
- They fit well on almost any substrate.
- They dry quickly and do not have a pungent odor.
Many people think that water-based and water-dispersion formulations are the same.
However, they are different.
- Matte emulsions wash off over time. The dispersions are waterproof and suitable for use in damp areas.
- Water-dispersion compositions are usually white; water-based analogues have a variety of colors.
- Dispersions cannot be used at temperatures below +5 degrees. However, with the addition of modifiers, they are thermally stable. Such, for example, are fire-retardant paints for metal Polistil.
Note!
The best analogues from water-based paints - based on acrylic resins and polymers.
They have high elasticity and strength.
- Such compositions are frost-resistant after they are completely dry.
- They are vapor permeable.
- Suitable for alkaline substrates (concrete, plaster).
- These paints are tinted very well.
- Resistant to ultraviolet radiation, retains its original color for a long time.
- They have the ability to repel water.
- They have high mechanical stability.
About paint compatibility
First, you need to apply epoxy putty to the old coating.
Based on everything written above, we will answer main question article - is it possible to paint on enamel with acrylic paint and vice versa.
- Based on their composition, acrylic paints and varnishes can only be applied to the same old coating. They cannot be applied over alkyd enamels, due to incompatibility of diluents/solvents. The new coating will simply curl (raise) the enamel.
- In addition, it is not advisable to apply emulsion and dispersion compositions to old glossy and adhesive paints. The same applies to varnished bases.
- But after emulsion and dispersion materials, you can use any enamels and paints.
Now let’s talk about how to apply a coating of acrylic paint with your own hands without removing the enamel.
Note!
To do this, you need to create an intermediate layer that is resistant to both acrylic and organic solvents in a stable state.
It should consist of polyesters (for example, epoxy resin, polyurethane) with amine hardeners.
Such compounds are dissolved with acetone.
After puttying, acrylic primer is applied.
Nowadays many liquid putties and primers with the described composition are sold.
One of the best materials is "Inter Troton Spray".
- First, apply liquid putty over the enamel.
- Next, cover the surface with acrylic primer.
- Then you can paint the base.
Conclusion
If you are unable to withdraw old paint, then a new coating can be applied to it. However, there are nuances here. Some types of paints and varnishes are incompatible, so between them it is necessary to create an intermediate layer of neutral compounds. By watching the video in this article, you will expand your knowledge base.
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Alkyd or acrylic primer: which one to choose?
Surface preparation before finishing with any materials is extremely important. Priming helps save you money, significantly improve the quality of your repair and extend its service life. How to choose the right one Construction Materials and get the work done?
The primer is used for all types of substrates: metal, wood, concrete, brick, plaster, drywall, putty. Its main purpose is to provide a strong “grip” finishing materials, be it wallpaper, paint, varnish or tile, with a base. Paint and varnish technologies do not stand still, now you can find a primer that will protect wood from rotting and fungus formation, metal from corrosion, give plaster or putty special strength due to deep penetration or even color.
The choice of primer should be based on the type of substrate and the properties you want to give it. Available on store shelves today a large assortment acrylic and alkyd materials.
What is the difference between alkyd paint and acrylic paint?
The former are used for almost any reason. Their main advantage is that they are odorless. When repairing in small spaces acrylic primer is indispensable. However, if you need to carry out work on metal, then only alkyd material will help. It reliably protects iron from rust. Experienced builders prefer alkyd primers over acrylic primers for outdoor work.
The most common alkyd primer is GF-021. Its anti-corrosion properties can significantly extend the service life of metal products. In addition, the primer is often and successfully used for other types of substrates, for example, wood, drywall, brick, plaster. Specifications, which manufacturers indicate on the labels, give the right to call the GF-021 primer universal. In particular, this term appears on the jar of the Yaroslavl Color brand. If you are in doubt about which primer to buy, then you can safely choose GF-021 primer. Technical characteristics, including consumption per 1 m2 and drying time, vary across all product lines. Before purchasing, be sure to read the instructions for use.
Traditional flowers for alkyd primer are brown, red-brown and grey. The palette of this material does not always play great importance, since most often it is applied under finishing materials. As the primer absorbs and dries, it becomes dull, but can affect the color of the future coating. If you choose a primer for light-colored wallpaper, then alkyd will not suit you.
Among acrylic materials, deep penetration primers stand out. They are designed to strengthen loose and fragile foundations. These may include concrete, plaster, wood, cement, gypsum, plasterboard, and previously painted surfaces. This type of primer penetrates as deep as possible into the base and reduces its absorption capacity, allowing significant savings on subsequent painting works. You will find such soil in the “Yaroslavl Color” and “Norma” lines.
The Braska line also includes a deep penetration primer, but it has additional properties that are valuable for repairs. It contains a fungicide - a chemical substance to combat fungal diseases. The primer is ideal for woodworking, protecting the base from the formation of mold and harmful bacteria.
Acrylic primers, unlike alkyd ones, are colorless, some of them are used as an independent coating. This is your option if you are looking for a primer for gluing light wallpaper. This type of primer can be used both indoors and outdoors.
You don’t have to worry about the quality of the coating formed by the primer if you choose it taking into account the existing base and finishing materials. In this case, the soil will responsibly fulfill all the duties assigned to it.
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Alkyd primer is an excellent analogue of imported primer. It can be used in cases where the surface to be treated does not need to be pre-impregnated.
Advantages of alkyd primer.
— high soil strength;
- resistant to abrasion after drying;
— reliably covers resinous knots. They are not visible even after several years;
— any paints (acrylic, alkyd, enamel, latex and nitro paint), glue (wallpaper, universal, PVA) and putties (acrylic and acrylic) lie smoothly on it;
— in addition to metal surfaces, alkyd primer is suitable for priming wood, plastic, plaster, laminated surfaces, chipboard, fiberboard, concrete, as well as surfaces previously painted with any paint;
- can be used when negative temperature;
- low toxic chemical composition. Can work without using special means protection, it is enough that the room is simply well ventilated;
— you can dilute the alkyd primer or clean the surface from it using white spirit. Inexpensive and accessible chemical.
Disadvantages of alkyd primer.
- long drying period;
— if the alkyd primer has not dried completely, some paints may curl upon contact with it;
- only the upper part of the surface is processed. That is, the alkyd primer does not penetrate deep into the material and cannot be used as a fixative for crumbling and loose materials. For them it is necessary to use acrylic primers;
- construction bandage from synthetic material that are not completely bonded to the surface should not be wetted with an alkyd primer. Because the bandage will bubble and stretch;
— despite the fact that white spirit is not a highly toxic substance, it is still quite harmful.
Is it possible to apply alkyd paint over acrylic primer?
Therefore, until the alkyd primer dries completely, the room must be well ventilated;
— the tools used for priming (brush or roller) must be stored wrapped in a rag moistened with white spirit. To prevent air from entering, they are additionally wrapped in polyethylene. This way the tools can be stored for a week. Then they can only be cleaned with special means.
Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting projects: painting walls, metalwork, etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
In fact, the only similarity is that both are paints. They are completely different in composition.
The alkyd type can be called a more modernized version of oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Alkyd paints consist of polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy the surface layer of paint. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sunlight, that is, it does not fade, turn yellow or take on a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully performs its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming an acrylic film is compensated by a higher level of resistance to mechanical stress (deformation, scratches).
- Decorative properties. Alkyd compositions are distinguished by a more diverse range of shades and halftones, as well as generally brighter colors. On the other hand, acrylic paint lasts longer and does not require regular updating.
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither of these is recommended, especially if the substrate was painted relatively recently or if the surface is metal. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply the top coat of paint only after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
At the moment when the stage of painting the surface begins in the renovation, the obvious question comes to mind: what paint to choose? Surely the color scheme has already been chosen in accordance with the design, so the essence of the question is what type of paint and varnish material to choose for application. Popular options are alkyd and acrylic paints. Despite their similar names, they differ significantly in both composition and characteristics. What are alkyd and acrylic paints and what advantages or disadvantages do they have? This is what will be discussed in this text.
What are alkyd and acrylic paints made of, what are the differences?
Let's get to the analysis of the composition of these two types of paint. The main component of alkyd compositions is alkyd varnish, which is mixed with various fillers, as well as a solvent. The most commonly used pentaphthalic alkyd varnish is a very thick resin to which rosin, glycerin and vegetable oils are added.
The role of the solvent is most often assigned to purified kerosene or, simply put, white spirit. It copes excellently with the breakdown of fractions of fats, oils and various organic compounds, therefore it is excellent for diluting alkyd paints. For fillers of alkyd enamels, marble or granite chips are used due to their high dispersion index.
Coloring pigments are added to this composition, giving the enamel a certain color shade. Quite often, some additional additives are included in the composition that can add functionality to the enamel, for example, an antiseptic to prevent the formation of fungus on the wooden surface.
The basis of acrylic paint is an acrylic polymer emulsion, with which the color pigment is mixed. This emulsion, also known as plexiglass, is the binding agent. The solvent, unlike alkyd enamels, is water. The composition also uses additives that change the properties of the material, for example, improving viscosity and application to the surface or increasing the drying rate.
Features of the use of alkyd paints
Despite the difference in composition, both types of compositions can be called universal. However, let us turn our attention to the use of alkyd-based paints. They can be used for any type of work - external and internal, due to their high mechanical properties, saturation and brightness.
These paints are classified into two main groups - enamels and oil paints. The latter are considered a separate type of paint and varnish materials, but most of them contain alkyd resins, so they can be considered a type of alkyd paint.
Alkyd enamels are widely used in construction and decoration, because they come in both glossy and matte. There are even semi-matte compositions. The film formed by glossy enamels is resistant to abrasion and can be used both for application on wooden surfaces, and on metal ones, in order to protect them. Glossy enamel lies more evenly on the surface and gets dirty a little worse than matte ones.
The choice of matte alkyd enamel is based rather on the taste of the buyer, because in terms of performance properties they do not differ from glossy ones. If you don't like glare from a painted surface, then matte alkyd enamel will suit you better. These surfaces are a little more susceptible to contamination, but this is a minor problem, because any alkyd paint is resistant to strong detergents and cleans well.
Comparison by main properties
Paint drying. The film obtained after applying alkyd enamel dries quite quickly than acrylic film. After just a few days, the alkyd film can properly perform its functions - both protective and decorative. For acrylic materials, the complete formation of the film takes a week or even more, and during this time the surface must be protected from mechanical stress.
Durability. The service life advantage is on the acrylic side. Intense exposure to the external environment means that alkyd surfaces have to be renewed after just a year. Moreover, if all preparation and application rules have been followed, the acrylic coating can last up to 8 years without the need for repainting.
More resistant to ultraviolet radiation acrylic materials. Unlike alkyd compounds, they do not fade and generally do not change the properties of the surface film.
Acrylic paints are also more resistant to mechanical impact, which in its way compensates for the longer preparation for the use of such coatings than for alkyd enamels.
While acrylic shows itself to be a more durable and stable material, alkyd-based compositions have a wider range of colors and shades, and after application the colors look much more vibrant.
Advantages and disadvantages of paints
Alkyd enamels have these advantages:
- More low price and ease of application, which is especially important when choosing a material for large areas of painting.
- Alkyd compositions have a large selection of shades, and the paint itself will not lose its color when dried.
- They dry quickly, and the protective characteristics appear within a couple of days.
- Alkyd enamels perfectly protect metal surfaces from rust and corrosion, and the film formed after application protects the surface well from aggressive cleaning agents such as bleach or bleach.
Alkyd compositions also have the following disadvantages:
- In the long term, they are not very reliable; over time, the surface will turn yellow and become cracked, so the paint will have to be renewed annually.
- Alkyd paints contain unsafe chemical components, causing bad smell which appear upon drying.
At the same time, acrylic paints have their own competitive advantages
- Long service life and increased resistance to external irritants, which will retain excellent performance properties.
- A good option for indoor use, because there is no release of odor or harmful substances.
- Good possibility for use even in the most high temperatures heating surfaces - for example for heating pipes.
Disadvantages of acrylic compositions:
- The cost of such paints will be higher, but the selection will be truly quality composition- more difficult. Its protective characteristics acrylic surfaces purchases take longer – from several weeks to a month.
Compatibility of alkyd and acrylic materials
Sometimes you may come across the question: is it possible to use acrylic paints to repaint alkyd surfaces? Or vice versa, is it possible to apply alkyd-based compositions over acrylic? There is only one answer - it is not recommended. Moreover, it makes no difference what kind of surface we are talking about, metal or wood.
The exact composition of any paint and varnish material cannot be fully known. Applying acrylic enamels over alkyd may result in the fact that the active components of the latter may appear through the top layer in the form of darkened spots and streaks, thereby ruining the entire surface. Otherwise, the alkyd paint may simply not adhere to the acrylic surface, as a result of which it will gradually peel off from the surface.
However, if a significant period of use of the painted surface has already passed and volatile elements have eroded from its surface, then it is possible to apply materials on top of each other. However, this should not be done on a “bare” surface anyway; it requires Preliminary processing primer. Important point– the primer must be the same type as the paint you will be reapplying.
Production of alkyd and acrylic compositions
Although the trend in production is to produce environmentally pure materials, which are diluted with water, namely acrylic compositions, the main component produced by domestic factories are alkyd binders of paints and varnishes. To be precise, more than 65% of everything paint and varnish production It is alkyd materials that occupy.
It is worth noting that foreign companies They are conducting much more active research into polymer compounds that are the basis for acrylic paints, as well as additives to these compounds. New technologies are being developed, the main emphasis of which is on environmental friendliness. In this regard, acrylic products are more attractive from the point of view of use. However, the price of such a product is much higher, which ultimately greatly influences the consumer’s choice.
To summarize, alkyd-based paints are a very attractive choice - they are inexpensive, bright, dry quickly and have good durability. However, in long term, acrylic enamels have an advantage, given that they are less toxic and can retain their properties for decades.
Repairing painted surfaces is an inevitable process. Even if the finishing was previously done competently and with high-quality materials.
At the moment, there are many ways to remove old paint.
- Mechanical methods. Acrylic enamel and acrylic paint or other coating are removed with sharp objects or power tools, such as a drill with an attachment.
- Thermal methods. In this case, the paint is softened, for example, with a hair dryer, and then removed.
- Chemical methods. The finish is removed using a variety of removers.
However, the process of removing the old coating is long and labor-intensive. And the price is quite high, especially if you need to remove paint from a large area or complex surfaces. Based on this, many of us prefer to apply a new finish directly to the old one. In this case, the question of compatibility of coatings often arises.
In this article we will talk about whether acrylic paint can be applied to enamel and vice versa. However, first we will understand the basic concepts.
Types of paints and varnishes
The composition of paints and varnishes includes binders, fillers, pigments, solvents/thinners and additives. In order to competently use paint and varnish materials during repairs, you need to know exactly their composition.
Main Components
All paints are divided according to the type of binder used and the type of solvent.
- The binder determines the main qualities of the paint, the service life of the coating and the speed of its drying. There are 4 common types of binders used for paints and varnishes: alkyd and epoxy resins, oil-based (on drying oil), latex, acrylic polymers.
- Solvent components are divided into solvents and diluents.. The former reduce the fluidity and viscosity of the material. Thinners only reduce the viscosity of the paint.
- To improve the characteristics of paints and varnishes, additives are added to their composition.: stabilizers, emulsifiers, fungicides, antiseptics, etc.
- Special paints belong to a separate category. These are anti-corrosion coatings, for example, Zinga electrically conductive paint. Analogs with antiseptic properties that protect the base from mold and rot. Compositions for removing small defects (irregularities, scratches, cracks), etc.
Oil and enamel compositions
Materials based on alkyd and acrylic resins include oil and enamel paints. They are suitable for painting metal, wood and plastered surfaces.
After drying, they are non-toxic, light and moisture resistant.
- Oil paints are produced on the basis of drying oil. White Spirit, gasoline, turpentine or solvent naphtha are used as diluents. The compositions are not expensive, but they take a long time (up to several days) to dry. The main disadvantage is that over time the coating turns yellow.
- Varnish is added to enamel compositions as a binder. It gives the coating gloss and aesthetics. The instructions recommend using such paints for exterior paints and on metal, wood, concrete, and plaster. Enamels are moisture and light resistant. They also have anti-corrosion resistance.
Emulsion and dispersion materials
Such paints are diluted, but not soluble with water. In them, the binder and pigment particles are distributed in a liquid medium, creating a stable emulsion.
When the coating dries, it is not washed away by water.
- Emulsion compositions are economical, environmentally friendly and fire safe.
- They fit well on almost any substrate.
- They dry quickly and do not have a pungent odor.
Many people think that water-based and water-dispersion formulations are the same.
However, they are different.
- Matte emulsions wash off over time. The dispersions are waterproof and suitable for use in damp areas.
- Water-dispersion compositions are usually white; water-based analogues have a variety of colors.
- Dispersions cannot be used at temperatures below +5 degrees. However, with the addition of modifiers, they are thermally stable. Such, for example, are fire-retardant paints for metal Polistil.
Note!
The best analogues of water-based paints are based on acrylic resins and polymers.
They have high elasticity and strength.
- Such compositions are frost-resistant after they are completely dry.
- They are vapor permeable.
- Suitable for alkaline substrates (concrete, plaster).
- These paints are tinted very well.
- Resistant to ultraviolet radiation, retains its original color for a long time.
- They have the ability to repel water.
- They have high mechanical stability.
About paint compatibility
Based on everything written above, we will answer the main question of the article - is it possible to paint on enamel with acrylic paint and vice versa.
- Based on their composition, acrylic paints and varnishes can only be applied to the same old coating. They cannot be applied over alkyd enamels due to incompatibility of thinners/solvents. The new coating will simply curl (raise) the enamel.
- In addition, it is not advisable to apply emulsion and dispersion compositions to old ones. The same applies to varnished bases.
- But after emulsion and dispersion materials, you can use any enamels and paints.
Now let’s talk about how to apply a coating of acrylic paint with your own hands without removing the enamel.
Note!
To do this, you need to create an intermediate layer that is resistant to both acrylic and organic solvents in a stable state.
It should consist of polyesters (for example, epoxy resin, polyurethane) with amine hardeners.
Such compounds are dissolved with acetone.
Nowadays many liquid compositions described are sold.
One of the best materials is Inter Troton Spray.
- First, apply liquid putty over the enamel.
- Next, cover the surface with acrylic primer.
- Then you can paint the base.
Conclusion
If you do not have the opportunity to remove the old paint, then a new coating can be applied to it. However, there are nuances here. Some types of paints and varnishes are incompatible, so between them it is necessary to create an intermediate layer of neutral compounds. By watching the video in this article, you will expand your knowledge base.
