Compatibility of varnishes nts and on a water basis. Material compatibility in coating systems. Paints and varnishes based on cellulose ethers

paints and varnishes are applied to the surface to be protected, as a rule, in multilayer systems, which may consist of primers, fillers, enamels for various purposes. At the same time, the paintwork materials included in the system can be heterogeneous not only in terms of the pigment part, but also in terms of the film-forming base, but they must be compatible with each other. ISO 12944-5 defines paint compatibility as the ability of two or more paint materials to be used in a coating system without undesirable effects. The use of materials with incompatible binders and solvents that do not provide the necessary interlayer adhesion or a high-quality uniform layer-by-layer coating leads to the need to remove a low-quality coating and repeat the preparatory and painting work.

When formulating coating systems, it is best to use materials with one type of binder. This is especially true for chemical curing materials (epoxy and polyurethane). To ensure the necessary interlayer adhesion when applying these materials on them, it is necessary to follow the recommendations for the intercoat drying time very accurately. Epoxides and polyurethanes contain very active solvents (xylene, acetone, cyclohexanone), so these materials cannot be applied over reversible physical curing coatings (chlorinated rubber, vinyl, copolymer-vinyl chloride, nitrocellulose, etc.), because. dissolution of reversible coatings and formation of defects can occur. When applying epoxy or polyurethane coatings to materials that cure with oxygen in the air (alkyd, oil), swelling and sub-dissolution of these coatings and delamination of the entire coating from the metal can occur.

Polyurethane top coats can only be applied over polyurethane, polyvinyl butyral or epoxy primers and top coats, subject to intercoat drying conditions to ensure intercoat adhesion. Epoxy enamels can only be applied over epoxy, polyvinyl butyral, zinc silicate and ethyl silicate primers and enamels.

Silicone and silicate paints and varnishes are not recommended to be applied over any other types of paints and varnishes, because. most of them are heat curing materials.

Alkyd and oil enamels can be applied on almost all physical curing paints and varnishes, except for bitumen and pitch. In the case of using alkyd and oil enamels on coatings containing bitumen and pitch, the latter may migrate to the upper layers and change their color.

Vinyl, copolymer-vinyl chloride and chlorinated rubber materials can be applied over polyvinyl butyral, acrylic, epoxy ester, zinc silicate and epoxy materials.

When choosing paints and varnishes for repairing coatings after operation, it is first necessary to clarify the paints and varnishes used in the previous painting.

When repairing, it is better to use the same paints and varnishes as in the previous painting or similar ones (on the same binder).

To eliminate errors, it is best to use the experimentally verified recommendations given in technological instructions or other documents related to this material.

Generalized experimental data on the compatibility of coatings on various film-forming bases are presented in Table. one.

Notes:

“+” - you can apply

“-” - can not be applied

“number” - can be applied with the following restrictions:

1. In case the epoxy ester film former is diluted

white spirit;

2. If bitumen and pitch do not penetrate (do not migrate) to the surface

3. When applying anti-fouling enamel, it is advisable to use

intermediate layer to prevent the diffusion of toxins into the bituminous

(pitch) underlying layers;

4. After adhesion test due to the variety of incoming solvents;

5. After roughening the coating or tack;

6. After operation for at least 3 months.

When choosing shop (factory) primers, it is necessary to take into account their compatibility with those used in further systems coatings. For right choice table should be followed. 2. (recommendations of ISO 12944-5).

Table 3.2

Compatibility of shop (factory) primers with paints and varnishes based on various film-forming agents

Notes:

“+” - Compatible

“(+)” - Check for compatibility with the paint manufacturer

“-” - No compatibility

1) - Including combinations with epoxies, eg based on coal tar lacquer.

All photos from the article

In most cases, the compatibility of wood varnishes is determined by the venue. painting works, that is, it can be painting lumber structures on the street, or it can be painting indoors. The difference lies in the fact that the outside is exposed to natural atmospheric phenomena - these are temperature changes and precipitation, including hail, so the finish during operation experiences various thermal and mechanical loads all the time.

The construction market offers enough a large number of such varnishes, and we will look at some of them, as well as show you a video in this article.

Types and characteristics

How are they classified

Note. Since there are a lot of varnishes, the instruction recommends using them according to the place of application, according to the degree of gloss and composition.

• At the place of application, such compositions are classified as those used for parquet - these are the most wear-resistant coatings that must withstand loads even from walking in heels with metal heels. Furniture coatings are also very popular - they are very often used in household for various crafts and the same furniture.

Less applicable compositions for boats (they have a very high water resistance), as well as for decorative works where strength is not so important.

• You can always determine the degree of gloss visually - it's easy and the coating speaks for itself. So, such coatings are high-gloss, glossy, semi-gloss, matte and semi-matte, but the price does not depend on this.
• And, finally, the compositions that are the main fundamental in the classification of paintwork materials. So, they are acrylic, water-based, alkyd, polyurethane, epoxy, or they can be nitro-varnishes.

Lineups

The production of alkyd varnishes is carried out on the basis of alkyd resins, from which, in fact, the name of the classification comes from, and organic solvents, they can be used for outdoor and / or for internal works, that is, they can be universal.

This lacquer external works on wood has great strength and resistance to moisture, so it is used not only on the street, but also in rooms with high humidity, for example, in the bathroom. The main disadvantage of this composition can be called a long drying time - this lasts up to 72 hours, but if a special hardener is involved, the process is reduced to 24 hours.

The cleanest and safest is acrylic lacquer odorless on wood water based, which has a high rate of strength during operation, in addition, it is quite elastic and is able to preserve the natural color and structure of wood.

In order for crystallization to take place in normal mode, the humidity must be within 50%, and it is applied using spray guns and paint rollers. Such a varnish in cans for wood is made in the composition with a hardener, which significantly increases not only the process of its solidification, but also increases the operational strength for abrasion.

Perhaps the most waterproof varnish among all analogues can be called epoxy - it not only has a very high moisture resistance, but, in addition, it is resistant to chemically aggressive substances and mechanical damage, that is, abrasion and impact. It is used both for internal and external works, and the time of its final solidification will not exceed 12 hours.

Nitrolac may be a mixture of lacquer colloxylin, and different brands, resins and plasticizers - all this is presented in a solution of volatile organic solvents - it is used mainly for internal finishing works.

Such coatings are mainly distinguished by their low cost, for which they have gained wide popularity, although, without the slightest doubt, high mechanical strength to impact and friction, as well as very fast drying of the surface, depending on the air temperature.

But the whole problem of such coatings is that they are produced on the basis of toxic solvents that are extremely harmful to human health and you need to work with them only with gloves, goggles and respirators.

Probably the most popular among professional craftsmen and repairers, is a group of varnishes based on polyurethane - they are all resistant to abrasion, mechanically strong and resistant to aggressive chemical influences.

It is noteworthy that the range of such coatings is not limited by the number and brand of manufacturers, but is determined by the scope of their use, for example, it can be parquet finishing, but it can also be painting musical instruments where quality requirements are highest.

An interesting method of applying such a composition - most often it is applied to the surface to be treated with a metal spatula and thereby closes all cracks and irregularities, but to create good adhesion rough surface must be well cleaned and dried - this largely determines the quality of the coating.

Note. It should also be noted that there is such a category as food grade wood varnish, for example, XC-46, which is characterized by increased resistance to chemical reagents and substances that may be contained in foodstuffs. It contains a solution of a vinyldenine chloride copolymer and a vinyl chloride elastomer in solution with organic solvents. Such compositions are used mainly for the kitchen sector.

Conclusion

Of course, do-it-yourself painting work with varnishes of any composition does not present any exceptional difficulty for the performer if everything is done according to the manufacturer's instructions. But in addition to the technical aspect, the manufacturer always indicates precautions that should not be neglected in any case!

Having independently taken up the repair of your apartment, you should have an idea about the materials that you have to use. Doing any - capital or cosmetic - repair, you can not do without paints and varnishes.

If in the store you come across a knowledgeable seller who, moreover, does not mind helping you in choosing a paint, you are in luck. But luck is not always and not for everyone. Therefore, often you have to choose yourself, and there is plenty to choose from.

In terms of their constituent components, paints are not always compatible with each other and with other coatings on which they are to be applied. Therefore, it is better to immediately choose paints that are compatible with each other, so that you do not have to bitterly regret the wasted money and time.

On the label of any paint, you can see its composition, but usually it is an alphanumeric code, which we will understand.

Paints and varnishes based on polycondensation resins

AU - alkydurethane
UR - polyurethane
GF - glyptal
FA - phenol-alkyd
KO - organosilicon
FL - phenolic
ML - melamine
CH - cyclohexanone
MP - urea (urea)
EP - epoxy
PL - polyester saturated
PE - unsaturated polyester
ET - etrifthalic
PF - pentaphthalic
ESP - epoxy ester

Paints and varnishes based on polymerization resins

AK - polyacrylate
MS - oil-alkyd styrene
VA - polyvinyl acetate
NP - petroleum polymer
VL - polyvinyl acetal
FP - fluoroplastic
VS - based on vinyl acetate copolymers
XC - based on vinyl chloride copolymers
XV - perchlorovinyl
KCh - rubber

Paints and varnishes based on natural resins

AC - alkyd-acrylic
BT - bituminous
ShL - shellac
KF - rosin
YAN - amber
MA - oil

Paints and varnishes based on cellulose ethers

AB - acetobutyrate cellulose
NC - cellulose nitrate
AC - cellulose acetate
EC - ethyl cellulose

The first digit after the letter code indicates the purpose of the paint or resistance to certain conditions:

1 - weatherproof
2 - resistant indoors
3 - for the preservation of metal products
4 - resistant to hot water
5 - for non-hard surfaces
6 - resistant to oil products
7 - resistant to aggressive environments
8 - heat resistant
9 - electrical insulating
0 - varnish, primer, semi-finished product
00 - putty

Sometimes, to clarify the specific properties of the paintwork, a letter index is put after the number: B - high-viscosity; M - matte; H - with filler; PM - semi-gloss; PG - low flammability.

For putties and primers after zero or zeros indicates on which drying oil it is made:

1 - natural drying oil;
2 - drying oil "Oksol"
3 - glyptal drying oil
4 - pentaphthalic drying oil
5 - combined drying oil

Compatibility of paints and varnishes

Having information about the composition of the paint, it is easy to choose the right ones for binding components primer and putty. But in case this is not at hand, there are compatibility options for dissimilar binding components:

Paint - Compatible Old Coats

AS - AC, VL, MCH, PF, FL, HV, EP
MS - AK, AS, VG, GF, PF, FL
AU - VL, GF, FL, EP
GF - AC, VL, KF, PF, FL, EP
KF - VL, GF, MS, PF, FL
KCh - VL, FL, HV, XS, EP
KO - AK, VG
MA - VL, KF, MS, GF, PF, FL
ML - AK, VL, GF, KF, MS, MCH, PS, FL, EP, EF
MCH - AK, VL, GF, KF, ML, PF, FL, EP, EF
NTs - AK, VL, GF, KF, PF, FL
AK - VL, GF, MCH, FP, EP, EF
HV - AC, VL, GF, CF, ML, MS, PF, FL, HS, EP, EF
UR - AK, VL, GF, PF, FL
PE - VL, GF, KF, ML, MS, PF, FP
PF - AC, VL, GF, KF, FL, EP, EF
HS - AC, VL, GF, CF, PF, FL, HV, EP
EP - AC, VG, VL, GF, PF, FL, HS, EF
EF - VL, KF, ML, FL
ET - VL, GF, MCH, PF, FL, EP

Primer - Compatible putties

AK - GF, MS, NC, PF, HV
AU - GF, PF
VL - GF, KF, MS, PF
GF - KF, MS, NC, PF
KF - GF, MS, NC, PF
ML - GF, MS, PF
MCH - GF, MS, PF
NC - GF, KF, NC, PE
PF - GF, KF, MS, NC, PF, PE, HV
FL - GF, KF, MS, NC, PF, PE, HV
XV - XV
XS - XB
EP - GF, KF, MS, PF
EF - GF, MS, PF

Paint - Compatible putties

AS - GF, KF, MS, NC, PF
AU - GF, KF, PF
GF - GF, KF, MS, PF
MA - GF, KF, MS, PF
ML - GF, MS, PF
MS - GF, KF, MS, PF
MCH - GF, MS, PF
NC - GF, NC, PF
PF - GF, KF, MS, PF
PE - GF, KF, MS, PF
XV - PE, XV
XS - PE, XV
EP - GF, PF, EP
ET - GF, MS, PF

Of course, you can not comply with the compatibility requirements described above, but then get ready for the fact that the repair will have to be redone very soon.

If other than decorative effect If you need to protect surfaces from the destructive action of various aggressive environments, then it is better to buy high-quality Belinka paint. This acrylic ceiling paint adheres perfectly to almost any surface - from perfectly prepared to old coatings.

Alkyd and acrylic paints are among the most common types of paint when it comes to serious painting jobs: wall painting, metal products etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have something in common?

Compound

In fact, the only similarity is that both are paints. Their composition is completely different.

Alkyd type can be called a more modernized option oil paints. They are characterized by a similar mechanism of hardening and the 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. The composition of paints may include various additional components designed to improve certain properties (add elasticity, speed up drying).

Basic properties

• Life time. In acrylic paint, unlike alkyd, the surface retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet intensely destroy surface layer paints. Acrylic coating, subject to the technology of surface preparation and paint application, can last from 8 (wood) to 20 (plaster) years.
• UV resistant. Acrylic practically does not change the properties of the surface film under the influence of sun rays, that is, it does not fade, does not turn yellow and does not take on a “matte” look. Alkyd compounds in this regard are not so reliable.
• Drying process. But the alkyd film dries relatively quickly, and after a couple of days it fully performs its protective and decorative functions. Acrylic film finishes its formation in about 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 acrylic film formation is compensated by more high level resistance to mechanical influences(deformations, scratches).
• decorative properties. Alkyd compositions are distinguished by a more diverse range of shades and halftones, as well as, in general, more bright colors. On the other hand, acrylic paint lasts longer and does not require regular renewal.

Are acrylic and alkyd paints compatible?

Can alkyd compounds be applied to acrylic or vice versa? Neither is recommended, especially if the painting of the base is relatively recent or if it is metal surface. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compounds may contain components that will show through the layer of acrylic paint as dark spots. If alkyd paint is applied over acrylic, then it may not be fixed on it, that is, it may peel off.

The only option for applying such paints to each other: applying to the old coating, from which all volatile components have already disappeared. However, even in this case, apply upper layer paint should only be done after the surface has been treated with a primer of the same type (i.e., acrylic paint on acrylic primer and vice versa).

There are several types of acrylic paints:
a) water-based acrylic paints (interior or facade paints);
b) two-component acrylic enamels (car acrylic paints in a jar).
They contain two components: paint and hardener, polymerize due to chemical reaction with a hardener, and this reaction is irreversible.
c) one-component acrylic enamels (used in aerosols). Dry in air by 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 resistant.

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 one on the other with acrylic and alkyd aerosol paints. But you need to apply the paint application no later than 30 minutes after applying the last coat of paint (acrylic or alkyd).

8. Can acrylic paint be applied to alkyd and vice versa?

Also, important role solvent plays. If the solvent is aggressive, then it can dissolve the alkyd paint. Usually more aggressive solvents are found in acrylic one-component paints. Therefore, in the case of applying an acrylic one-component paint to an alkyd paint, care must be taken to first ensure that the coating is not adversely affected.

In the case of applying alkyd one-component paint on acrylic, subject to temporary recommendations (no later than 30 minutes after applying the last coat 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 under the condition that earlier finishing was 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 is peeled off sharp objects or a power tool, such as a drill with a nozzle.
• thermal methods. In this case, the paint softens, for example, building hair dryer and then removed.
• Chemical methods. The finish is removed with a variety of washes.

However, the process of removing the old coating is long and labor-intensive. Yes, and the price of the issue is quite high, especially if you need to remove paint from large area or complex surfaces. Based on this, many of us prefer to apply new finish directly on the old one. In this case, the question of the compatibility of coatings often arises.

In this article we will talk about whether acrylic paint can be applied to enamel and vice versa. But first, let's look at the basic concepts.

Varieties of paints and varnishes

The composition of paints and varnishes includes a binder, fillers, pigments, solvents / thinners and additives. In order to correctly apply paintwork 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.

1. The binder determines the main qualities of the paint, the service life of the coating and the speed of its drying.. There are 4 types of binders used for paintwork materials: alkyd and epoxy resins, oil (on drying oil), latex, acrylic polymers.
2. Solvent components are divided into actual solvents and diluents.. The former reduce the fluidity and viscosity of the material. Thinners only reduce the viscosity of the paint.
3. To improve the characteristics of paintwork materials, additives are added to their composition.: stabilizers, emulsifiers, fungicides, antiseptics, etc.
4. A separate category includes special paints . This is anti-corrosion coatings, for example, electrically conductive paint Zinga. Analogs with antiseptic properties protecting the base from mold and decay. Compositions for removing small defects (irregularities, scratches, cracks), etc.

Oil and enamel formulations

Pictured is acrylic paint.

To materials based on alkyd and acrylic resins include oil and enamel paints.

They are suitable for painting metal, wood and plastered surfaces.

After drying, it is non-toxic, light and moisture resistant.

1. Oil paints are produced on the basis of drying oil. As thinners for them are White Spirit, gasoline, turpentine or solvent naphtha. The price of the compositions is low, but they dry for a long time (up to several days). The main disadvantage is that over time the coating turns yellow.
2. AT enamel compounds, as a binder, varnish is added. It gives the coating gloss and aesthetics. The instruction recommends using such paints for external and internal finishing work on metal, wood, concrete, and plaster.

   Differences between alkyd and acrylic paints

   Enamels are moisture and light resistant. They also have anti-corrosion resistance.

Emulsion and dispersion materials

Water-dispersion composition.

Such paints are diluted, but do not dissolve with water. In them, the binder and pigment particles are distributed in a liquid medium, thus creating a stable emulsion.

When the coating dries, it does not wash out with water.

1. Emulsion compositions are economical, have environmental friendliness and fire safety.
2. They fit well on almost any substrate.
3. Dries quickly, does not have a strong smell.

Many people think that water-based and water-dispersion formulations are the same.

However, they are different.

1. Matte emulsions are washed off over time. The dispersions are water-resistant and suitable for use in wet areas.
2. Water-dispersion compositions are usually white, water-based analogues have a variety of color palettes.
3. Dispersions cannot be used at temperatures below +5 degrees. However, when modifiers are added, they are thermally stable. Such, for example, fire-retardant paints for metal Polistil.

Note!
The best analogues from paints diluted with water - based on acrylic resins and polymers.
They have high elasticity and strength.

1. Such compositions are frost-resistant after their complete drying.
2. Possess vapor permeability.
3. Suitable for alkaline substrates (concrete, plaster).
4. These paints are well tinted.
5. Resistant to ultraviolet, retain the original color for a long time.
6. They have the ability to repel water.
7. They have high mechanical stability.

About paint compatibility

First, an epoxy putty must be applied to the old coating.

Based on everything written above, we will answer main question articles - is it possible acrylic paint paint on enamel and vice versa.

1. Based on their composition, acrylic coatings fall only on the same old coating. They cannot be applied over alkyd enamels due to thinner/solvent incompatibility. The new coating will simply fold (raise) the enamel.
2. In addition, it is undesirable to apply emulsion and dispersion compositions on old glossy and adhesive paints. The same applies to lacquered bases.
3. But, after emulsion and dispersion materials, any enamels and paints can be used.

Now about how, without removing the enamel, apply a coating of acrylic paint with your own hands.

Note!
To do this, you need to create an intermediate layer, in a stable state, resistant to both acrylic and organic solvents.
It should consist of polyesters, (for example, epoxy resin, polyurethane) on amine hardeners.
Such compounds are dissolved with acetone.

After puttying, acrylic primer is applied.

Now many liquid putties and primers are sold that have the described composition.

One of the best materials is "Inter Troton Spray".

1. First, apply liquid putty over the enamel.
2. Next, cover the surface with acrylic primer.
3. 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 coatings are incompatible, so between them you need to create an intermediate layer of neutral compositions. 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 your money, significantly improve the quality of repairs and extend their service life. How to choose the right Construction Materials and do the work?

The primer is used for all types of bases: metal, wood, concrete, brick, plaster, drywall, putty. Its main purpose is to provide a strong "seizure" 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 decay and the formation of fungus, metal from corrosion, plaster or putty to give 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. Presented 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 metal work, then only alkyd material. It reliably protects iron from rust. Experienced Builders prefer alkyd primers to acrylic primers for outdoor use.

The most common among alkyd primers 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, such as wood, drywall, brick, plaster. Specifications, which are indicated by manufacturers on the labels, give the right to call the primer GF-021 universal. In particular, the bank trademark"Yaroslavl flavor" is the term. If you are in doubt about which primer to buy, then you can safely choose the primer GF-021. Specifications, including consumption per 1 m2 and drying time, vary in all product lines. Before buying, be sure to read the instructions for use.

Traditional colors for alkyd primers are brown, red-brown and gray. The palette of this material does not always play great importance, since most often it is applied under finishing materials. Absorbing and drying, the primer becomes dull, but it can affect the color of the future coating. If you choose a primer for light wallpaper, then alkyd will not work for you.

Among acrylic materials primers stand out deep penetration. They are designed to strengthen loose and fragile foundations. Among them may be concrete, plastered, wood, cement, gypsum, plasterboard, previously painted surfaces. This type of primer penetrates as deep as possible into the substrate and reduces its absorption capacity, allowing significant savings on subsequent painting work. 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 valuable properties for repairs. It contains a fungicide - Chemical substance to fight fungal diseases. The primer is ideal for woodworking, protecting the substrate 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 glue primer. light wallpaper. This type of primer can be used both indoors and outdoors.

You can not 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 treated surface does not need to be pre-impregnated.

Advantages of alkyd primer.

— high strength soil;

- resistant to abrasion after drying;

— reliably closes 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 (acrylate and acrylic) lie flat on it;

- in addition to the metal surface, the alkyd primer is suitable for priming wood, plastic, plaster, laminated surfaces, chipboard, fiberboard, concrete, as well as surfaces previously painted with any paints;

- can be used with negative temperature;

– low toxicity chemical composition. Can work without using special means protection, it is enough that the room is simply well ventilated;

- dilute the alkyd primer or clean the surface from it with white spirit. Inexpensive and readily available chemicals.

Disadvantages of alkyd primer.

— a long period drying;

- if the alkyd primer is not completely dry, some paints may curl upon contact with it;

- processed only top part surfaces. 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 synthetic material which are not fully adhered to the surface, must 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.

Can alkyd paint be applied over acrylic primer?

Therefore, until the alkyd primer is completely dry, 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 exclude air access, they are additionally wrapped in polyethylene. In this way, instruments can be stored for a week. Then they can be cleaned only with special means.

Compatibility of finishing paints and varnishes (LKM) with primers (or old paint and varnish coatings) Type LKM Type of primers + AC + + + + + GF + + + + + + + KO + MA + + + + ML + + + + + + + + MS + + + + + MCh + + + + + + + + NC + + + ХВ + + + + + + + + + UR + + + + + PF + + + + + + + EP + + + + + + + + + XC + + + + + + + + Paints and primers: VD - water-borne ; AC - alkyd-acrylic; AU - alkyd-urethane; EP - alkyd-epoxy or epoxy; GF - glyptal; KO - organosilicon; MA - oil; ML - melamine; MS - oil and alkyd styrene; MP - urea; NC - nitrocellulose; AK - polyacrylic; XV - polyvinyl chloride or perchlorovinyl; UR - polyurethane; PF - pentaphthalic; XC - copolymer-vinyl chloride; VL - polyvinyl acetal; AK - polyacrylate; FL - phenolic

Subsequent coating designation

Oil, oil-resin

Alkyd

Bituminous and pitch

Vinyl-pitch and chlorinated rubber-pitch

Vinyl

Polyvinyl-butyral

Chlorine rubber

Epoxy ester

Epoxy

Epoxy-pitch

polyurethane

Silicon-organic

Zincsilicate on liquid glass

Notes:

"+" - you can apply

"-" - can not be applied

"number" - can be applied with the following restrictions:

1. In case the epoxy ester film former is diluted

white spirit;

2. If bitumen and pitch do not penetrate (do not migrate) to the surface

3. When applying anti-fouling enamel, it is advisable to use

intermediate to prevent diffusion of toxins into bituminous

(pitch) underlying layers;

4. After adhesion test due to the variety of incoming solvents;

5. After roughening the coating or tack;

6. After operation for at least 3 months.

When selecting shop primers, consideration should be given to their compatibility with subsequent coating systems. For the correct choice, you should be guided by the table. 2. (recommendations of ISO 12944-5).

Table 3.2

Compatibility of shop (factory) primers with paints and varnishes based on various film-forming agents

Factory primer

Paint compatibility

binder type

Anti-corrosion pigment

Alkyd

Chlorinated rubber

Vinyl

Acrylic

Epoxy1)

Polyurethane

silicate/zinc powder

bituminous

1. Alkyd

mixed

2. Polyvinyl butyral

mixed

3. Epoxy

mixed

4. Epoxy

Zinc Powder

5. Silicate

Zinc Powder

Notes:

"+" - Compatible

"(+)" - Check for compatibility with the participation of the paint manufacturer

"-" - No compatibility

1) - Including combinations with epoxies, eg based on coal tar lacquer.