Lucky

Today we will introduce you to a large and respected group of building materials, namely varnishes. As for the area of ​​application and base material, they, like paints, are extremely diverse. Craftsmen of the paint and varnish industry constantly deal with thousands of intricate colors, each of which can be indispensable in the interior..

Varnishes belong to the group of paints and varnishes. In everyday life, five types of paints and varnishes are used.

Lucky – from natural or synthetic resins and drying oils diluted in water or organic solvents, they form a solid, uniform film, most often translucent. They give products a decorative look, for example, they emphasize the texture of valuable wood species, and are also used to create anti-corrosion and other protective coatings..
Paints – include pigment – a colored mineral crushed into powder. In addition, they contain a film-forming agent and a volatile component – water or organic solvent.
Enamels – are a mixture of varnish and pigment. The coatings created with their help are durable, beautiful and durable..
Primers – serve to create a rough finish. Their task is to reliably combine the surface film with the substrate.
Putties – intended for leveling surfaces, they contain various fillers.
To make it easier for us to understand the properties and scope of varnishes, let’s try to briefly classify them..

Surface to be treated

Varnishes are “friendly” with wood, metal or mineral base. For protective and decorative finishing of metal and mineral surfaces, as a rule, they use painted or white varnishes (according to the classification of many Western manufacturers). In our country it is customary to call them enamels and refer to paints..

Components

Varnishes can be divided into groups according to the number of components. Recently, the overwhelming majority of varnishes are one-component, although there are also special types, the curing of which occurs when two or more components are mixed, stored in different containers. Materials with more than two components are not used in everyday life. And many of us have used two-component domestic acid-cured parquet varnishes many times..

Designations of some domestic paints and varnishes according to the chemical composition of the film-forming substance: alkyd-acrylic – AC; alkyd-urethane – AC; polyurethane – UR; polyacrylic – AK; bituminous – BT; polyester – PE; glyphthalic – GF; oil – MA; pentaphthalic – PF; urea – MCH; nitrocellulose – NC; epoxy – EP; perchlorovinyl – HV; polyvinyl acetate – VA; epoxy ester – EF.

An important parameter of any paint and varnish material is environmental friendliness. In this regard, water-based varnishes stand out – they are free of toxic substances and practically odorless. Almost all materials with organic solvents have a strong odor, and therefore requires ventilation during operation. The general trend of recent years is the development and the widest possible use of varnishes that do not contain organic solvents, which makes them fire and explosion safe and allows you to work with them without respiratory protection.

Application

Another important factor when choosing a varnish is the place (object) of their application. Four large groups can be distinguished here. The first includes parquet varnishes. In recent years, instead of two-component floors, one-component alkyd-polyurethane and acrylate-polyurethane, which are used to cover doors, furniture and other wooden products, have been used for flooring. The second group is the so-called boat varnishes. They are distinguished by their very high strength and resistance to weathering, therefore they are also used for finishing garden furniture and other wooden products outdoors and exposed to sunlight, rain and snow, heat and cold. The most numerous is the group of varnishes for decorative and protective finishing of various wooden surfaces indoors and outdoors. Furniture varnishes constitute a special group..

Appointment

Paints and varnishes have protective or decorative functions. For example, a good water emulsion is not a serious barrier to rust. Therefore, before using it, the metal surface must be cleaned and primed. There is an easier way – go directly over the rust with a special compound containing glass powder. The color range of protective paints is not as wide as that of decorative paints. The result is less impressive, but economical. A side effect of this process is the release of toxic substances. Hazardous vapors are characteristic of materials based on a number of polymer resins, as well as containing lead, chromium and mercury compounds. Working with them requires compliance with safety precautions. It is better to refuse to use such products indoors..

And yet more often a modern person uses varnishes and paints with decorative properties. When painting facades and for most interior work, the appearance of the coating, its environmental friendliness, is important, and not at all the protection of materials. The ideal paints for such work are traditional water-based emulsion, as well as water-based paints with acrylic polymers. The latter are extremely durable and have unique properties. So, acrylic polymers easily retain not only particles of pigment crushed into powder, but also very weighty granite and marble chips. They are environmentally friendly. Acrylic paints are easy to dilute to the desired consistency and maintain in working order.

The coating, depending on the processing and the filler contained in the paint, becomes glossy or coarse-grained, with a complex surface structure. The paint can be multi-colored – the pattern is either “embedded” in the composition of the material, or is created during the formation of the coating. It is important that after the evaporation of water, micropores remain on the surface, due to which natural steam exchange is not disturbed in the room..

The staining process begins with the preparation of the base. Whether it’s concrete, metal, wood or plastic – it needs to be leveled, get rid of defects. First, the remnants of the old paint are removed, the ingrained salt is washed off, the surface is dried, if necessary, putty and polished. Next, apply a primer and only then – the first coat of paint.

Varnishing methods

Just like most paints, varnishes can be applied by brush, roller or spray. Recently, instead of a brush or roller, special varnish brushes have been used. In addition, there are three more ways to apply varnish. The names of two of them speak for themselves – dipping and filling (with a special machine). But the third, unusual method of varnishing with a wide metal spatula (squeegee) is widely used in repair work, however, mainly by professionals, when covering large and smooth flat surfaces. The layer turns out to be very even and thin, there are no drips, thickenings and defects that are inevitably formed when working with a roller or brush. And thanks to the low layer thickness, varnish consumption is reduced by 3-3.5 times.

Properties

The main properties of paints and varnishes are encoded on the labels. The system adopted in domestic production consists of several groups of signs.
The first group is the type of paints and varnishes. The label says “varnish”, “enamel”, etc. The exception is oil paints. They are designated by the pigment included in the composition (for example, “umber”, “ocher”, “red lead”).

In the second group of characters, the composition of the film-forming substance is encoded. For brevity, only two letters are left from the name. Let’s say cellulose acetate butyrate materials are labeled “AB” on the label. All compounds based on natural resins are considered safe: “KF” – rosin, “MA” – oil, “SHL” – shellac, “YAN” – amber; and also on synthetic ones: “E” or “VD” – water-dispersive, “AK” – acrylic, etc. Most of all poisonous vapors emit materials based on polycondensation and polymer resins: “FL” – phenolic, “CG” – cyclohexane, “ВС” – vinyl acetate.

Further, the purpose of the product is coded: 1 – weather-resistant (for outdoor use); 2 – limited weatherproof (for interior work); 3 – protective; 4 – waterproof; 5 – special; b – oil and petrol resistant; 7 – chemically resistant; 8 – heat-resistant; 9 – electrical insulating; 0 – primers; 00 – putties. For thick-grated oil paints, one zero is put before the third group of characters.

The fourth group of signs is important only for oil paints (in other cases, this is the serial number). Here the drying oil, on which the paint is made, is coded: 1 – natural; 2 – “Oxol”; 3 – glyphthalic; 4 – pentaphthalene; 5 – combined. After the number, the letter specification of specific properties is also possible: for example, “M” – matte; “N” – with filler; “PG” – low flammability.

Speaking of varnishes, the definitions are often used: high-gloss, glossy, semi-gloss, matte or semi-matte. For glossy varnishes, the degree of gloss is approximately 80-90%, semi-gloss – 40-50, semi-gloss – 10-15%.