To protect wood, concrete and polymer coatings from mechanical damage, moisture and other negative factors, the surface is opened with varnish. Today there is a wide variety of formulations that differ in technical and operational qualities. The most popular is polyurethane floor varnish, which is characterized by safety, high drying speed, strength and durability.
The use of varnish and varieties of chemical compositions
The floor surface is constantly exposed to mechanical and shock loads, which lead to the formation of scratches, cracks and chips. As a result of exposure to moisture, the integrity of the surface structure is violated. Ultraviolet rays adversely affect the appearance of the floor, distorting its original shade and texture.
As a finishing element for finishing the floor, paint and varnish is often used, which creates reliable protection of the base from various kinds of negative influences that arise as a result of its long-term use.
Note! Thanks to the transparent texture of the composition, it is possible to favorably emphasize the natural structure of natural wood and not spoil the pattern of the self-leveling concrete floor.
Varnishes are classified according to the type of binder in their composition. Depending on this, the following types of material are distinguished:
- acrylic floor varnish has good elasticity, provides acceptable strength to the base, resistant to abrasion. The main advantage is the low cost of the material;
- the oil composition is used as a preliminary layer before the final application of varnish, which helps to create a denser and more durable surface;
- alkyd floor varnish provides a surface that is resistant to mechanical damage, but it is less resistant to shock loads;
- polyurethane composition gives the base increased strength, abrasion resistance and durability;
- acrylic-polyurethane material is characterized by good strength and resistance to mechanical stress, but inferior to the previous version. The main advantage is the low price of the varnish;
- urethane floor varnish has good elasticity, abrasion resistance and low cost. The composition is used in rooms with low traffic;
- urethane-alkyd composition is characterized by increased resistance to abrasion and shock loads;
- alcohol varnish has good adhesion and durability. However, due to its low moisture resistance, it is not recommended for wood flooring.
Polyurethane floor varnish: material characteristics
Polyurethane varnishes are widely used to protect concrete, self-leveling, wooden floors, polymer coatings, stone processing, parquet, wooden furniture and other elements. Such compositions provide reliable surface protection against mechanical and chemical influences.
Water-based polyurethane floor varnish contains at least 40% of the substance in the dry residue, due to which it has a low cost compared to compositions based on chemical solvents.
Polyurethane varnishes have the following advantages:
- deep penetration of the composition into the surface provides it with high strength and elasticity;
- environmental safety and non-toxicity of the material;
- surface resistance to moisture, ultraviolet rays, temperature changes;
- high drying speed;
- promote the formation of a dense film on the surface with an increased level of wear resistance, resistance to mechanical damage and shock loads, the penetration of dirt into the pores of the coating;
- the composition provides a transparent surface that does not turn yellow over time, which allows you to emphasize the natural pattern of wood, fixing it in its original form, providing reliable protection against abrasion;
- due to active polymerization and low tension, the film after drying
- does not crack or exfoliate;
- varnish treatment of a wooden surface minimizes the likelihood of the germination of bacteria and the attraction of rodents;
- the composition interacts well with acrylic dyes, which allow you to obtain various shades of the surface.
The disadvantages include a persistent unpleasant odor at the time of application to the surface and the high price of polyurethane varnish.
Varieties of polyurethane varnish for wood
There are two types of polyurethane varnish: one-component and two-component. The first option is ready to use right away. It has a liquid consistency. This material is often produced as an aerosol. It is used for a small area. Most often they are covered with wooden furniture and decorative elements.
Helpful advice! The consumption of aerosol formulations is higher than that of liquid varnishes, so the material must be purchased with a margin.
The main advantage of one-component varnish is the absence of organic solvents and other toxic compounds in it. When dry, it is not able to release harmful substances into the air. One-component compositions are inferior in terms of quality to two-component ones.
Two-component polyurethane varnish for wood consists of a base and a hardener, which must be mixed in a certain proportion as indicated in the instructions. This composition is most often used for large surfaces.
Important! After mixing the components, the material retains its original performance for 4-5 hours.
There are also self-leveling compounds that provide an even, durable surface. They are often used for coatings with visible structural defects.
To reduce the cost of the material, some manufacturers dilute the polyurethane varnish with acrylic, which negatively affects the performance of the composition. Therefore, when choosing quality products, it is important to consider how much wood varnish costs. Cheap formulations are not able to provide the desired result.
Depending on the scope of use, two-component varnishes can be yacht, for plastic, furniture, parquet and universal. The latter option is intended for any type of surface. There are no latex components in plastic varnishes. Yacht compositions are actively used for finishing wooden yachts. It is also suitable for all wood surfaces. Yacht floor varnishes are characterized by high moisture resistance.
Polyurethane varnish is available in transparent form. However, there are compositions of various natural shades of natural wood, which allows you to paint the surface in the desired color.
Which is better for wood: matte varnish or glossy
Polyurethane varnishes not only favorably emphasize the natural pattern of wood, but also provide reliable protection of surfaces and products from mechanical damage, shock and the harmful effects of negative factors in the form of moisture, sun and abrasive materials. They are able to extend the service life of products while maintaining their original appearance.
After application, polyurethane varnish can form a semi-glossy, glossy, semi-matt or matte surface, each of which is characterized by high strength characteristics and differs only in aesthetic appearance.
The matte finish works best in rooms with diffused daylight. It is the best option for outdoor structures. Matt floor lacquer emphasizes the naturalness and naturalness of the wood, making its structure more expressive. It is also able to hide small cracks, scratches and other imperfections, so that the surface does not need to be sanded too thoroughly before varnishing. In addition, the matte finish is much easier to maintain.
The glossy water-based floor polish also enhances the texture of the natural material, giving the surface an extra shine. However, on such a coating, scratches and other minor damage stand out more clearly than on a matte finish. On such surfaces, streaks are visible, which makes it difficult to care for them. Glossy lacquer is best suited for wood furniture.
Semi-gloss and semi-gloss varnishes are “intermediate” compositions. The first option creates a slightly blurred surface, while the second gives it a subtle shine.
The technology of applying varnish on wooden surfaces
The method of applying varnish is determined by the composition of the material and the type of surface to be treated. Work should be carried out at a temperature of 20-23 ° C. The minimum permissible value is 13 ° C, and the maximum is 30 ° C. The relative humidity of the air should be within the range of 50-60%, which will ensure the natural drying process of the surface.
There are three methods for applying varnish to a wooden base:
- The surface is pre-treated with a stain to give it the desired shade.
- A polyurethane primer is applied to the wooden base.
- The polyurethane varnish is applied to the cleaned substrate in several layers.
Before using water-based polyurethane varnish for wood, it is necessary to prepare the base, which is ensured by eliminating chips, cracks and other defects, sanding the surface to a smooth coating. Further, dust and dirt are removed, and the surface is degreased. If the wood is previously stained to obtain the desired color, the floor varnish is applied after the coloring composition has completely dried.
Helpful advice! If a wooden surface or structure is located in a room with high humidity or is located outside the building, it is recommended to pre-treat it with an antiseptic compound.
How to use pine and natural wood floor varnish
Water-based polyurethane varnish for wood can be applied with a brush, felt roller or spray gun. In the latter case, up to 5-10% of the solvent is added to the composition.
Helpful advice! Before applying the varnish, it is recommended to walk with a dry brush over the surface to remove the lint, which will contribute to a cleaner and more accurate work.
The one-component varnish is immediately ready for use. If it covers stain or primer mixture, 2 coats of varnish will be sufficient. Each subsequent layer is applied after the previous one has completely dried, which occurs after 5-6 hours. The finishing base is completely cured after 12 hours.
Before using a two-component, wear-resistant, moisture-resistant floor varnish, it must be prepared by mixing the base and the hardener in a certain ratio. The solution should be infused for 20-25 minutes.
The varnish is applied to the wooden base along the surface of the fibers with smooth, slow movements, which eliminates the formation of bubbles and ensures an even distribution of the composition without streaks. When using a brush, the composition is distributed crosswise. Floor treatment should be started from the window, moving smoothly towards the door.
How to varnish concrete floors
To improve the operational characteristics of a self-leveling concrete floor, which is exposed to large and frequent loads, the surface is opened with polyurethane varnish. The base should be pre-prepared, leveled and cleaned from dirt and dust. To do this, you can use soapy water or clean the surface under the pressure of water. After which it should dry completely.
Before applying the self-leveling varnish, the dry base can be additionally vacuumed, which will allow you to get a perfectly clean surface and achieve a high-quality painted base.
If there are no polymer components in the self-leveling floor, the surface must first be primed, which will contribute to the formation of an airtight layer. This technology will also save the amount of varnish.
Important! Concrete surfaces are coated exclusively with two-component wear-resistant floor varnishes.
The choice of the required amount of working solution is carried out taking into account its use for 40-50 minutes.
A decor can be created on the surface of the self-leveling floor before applying varnish. For this, special stencils and coloring compositions are used. You can also use ready-made prints.
The technology of applying varnish to a concrete surface is no different from the method of processing a wooden base. First, they pass through hard-to-reach places with a brush. The varnish is applied to the surface in small patches.