Solvent for acrylic paints, varnish and glue - get acquainted with the selection rules. Polyurethane enamel: description, characteristics, types, application A short list of the most famous polyurethane floor varnishes
Source: painting and varnishing. Wooden Boat Series.
Doug Templin
Abridged translation by S.B.
What are polyurethanes
Although polyurethane compounds have been around for quite some time, they are still state of the art because little has moved in the direction of developing more advanced paint systems in all that time.
Immediately after the introduction of the first two-component polyurethane paints, they gained a reputation for durability, chemical and wear resistance, and good color retention. They were immediately adopted by aviation, where corrosion protection is of paramount importance, aesthetics are important, and the cost of painting work is extremely high. Having established themselves in aviation, polyurethane paints quickly moved into the realm of "marine" paints and varnishes for the same reasons. The automotive and industrial coatings industries are next in line, where the high cost of polyurethane paintwork justifies itself with increased resistance and durability. Today, there are an infinite number of applications for polyurethanes.
The chemical process for curing polyurethanes is relatively simple. It is a reaction of two compounds: one of them is called an isocyanate, the other is called a polyol, or high molecular weight alcohol. Isocyanate consists of chemical groups containing nitrogen, carbon and oxygen atoms, connected to each other in a special way, which gives them a high reactivity. The isocyanate production process was developed by the German company Bayer (the one that is famous for the invention of aspirin), the production license was sold to Monsanto in the USA. Later, they bought shares and created Mobay Chemical, which still produces the purest, most advanced isocyanates in existence today.
Over the years, much has been improved: reducing the volatility of isocyanates, making them safer and improving performance. While the word "isocyanate" carries an ominous connotation, it has nothing to do with cyanide, a known poison. Isocyanate is a respiratory irritant, and its solvents have a toxic effect.
The component referred to as a "polyol" is typically a high molecular weight alcohol supplemented with pigments, fillers, and other components, collectively referred to as the "pigmented base". The polyol has reactive hydroxyl groups (OH), exactly the same as those found in the water molecule H 2 O (H-OH). In alcohols that are used to form polyurethane, they have a very high activity, and their large amount leads to the formation of numerous reaction pairs with isocyanate, and when the components are mixed, a very dense three-dimensional network structure is formed.
The number of existing polyols is as large as the number of existing varnish and paint companies, each developed for a specific purpose or to fill a highly specialized market niche. The goals of their development can be cost-effectiveness, resistance to temperature and chemicals, formation of a thick coating film, protection against corrosion. The alcohols we use in marine paints are designed for high initial gloss and long lasting durability.
Marine polyurethane coatings
Let's take a closer look at what polyurethanes are designed for use in a "marine" environment. A definite difference between them lies in the two types of polyols used - those that contain acrylic resin and those that have a polyester base. It is the resin that determines the internal structure and allows you to predict in advance what the coating film will be capable of and what it will not. Acrylic systems are generally referred to as modified polyurethanes, while polyester systems are considered "pure" polyurethane.
Acrylic resin based paint systems are usually designed for minimum curing time, sufficiently hard surface and polishability. They are more vulnerable to temperature and chemicals, but this does not prevent them from dominating the automotive industry and other vehicles where polishability matters. Acrylic systems generally do not have the elasticity and abrasion resistance of their polyester counterparts.
Dupont's Imron system dominates among the acrylic-modified systems used for painting vehicles, and it is clear that it is also the leader among this type of "marine" systems. However, in highly corrosive environments and in southern latitudes, Imron does not appear to be as glossy and lightfast as high quality polyester systems. Since the latter tend to be more flexible, I think Imron is more suitable for metal and fiberglass boats than wood boats. Its use is also hampered by the fact that when painting with a brush, the result cannot be considered satisfactory.
Polyester systems are more commonly found in the jet industry, where solvent resistance and elasticity are mandatory requirements. This market is dominated by products from Sterling (Sterling System), US Paint (Awlgrip), International (Interthane) and Koppers (Z-Spar). All these systems have a polyester base and are quite different from each other, although they can be considered approximately equivalent in terms of their final consumer qualities. Each of these firms has its own brand of paint that can be applied with a brush, which attracts them to recent times fairly broad attention.
Conditions for coloring
There are a great many stories about how this or that paint behaves - we all heard about successes and complete fiascos, moreover, when it came to the same brand of paint. It is natural that any of us want to achieve a good result when painting a boat, so you should know in advance some of important conditions that will help achieve this.
Dry wood. Polyurethane paints can only be applied to wood that is evenly dried and in a state of equilibrium moisture content with environment. There should be no areas of manifestation on its surface. high content moisture, posing as bloating and bubbling. If the enamel paint stays on the hull for only one season - probable cause It could be the high moisture content of the wood. With damp wood, you will not succeed with polyurethane paints.
A suitable candidate for polyurethane paint application is healthy wood, well dried and dimensionally stable, although in practice it is more likely to get good result with hardwood. Problems can arise with wood such as resin pine, in which numerous knots are constantly "tearing".
Rigid base. If the hull or deckhouse of your boat experiences significant shear deformations between the plating belts, polyurethane paints cannot be used there. How older age boats, the more weakened its fasteners and the greater the shift relative to each other, the sheathing boards are likely to experience. This can be caused by dynamic loads that occur when the boat moves through the water, or simply when the boat moves from a very hot climate to a very cold one, from a very wet to a dry one, and vice versa.
Any body that has seamed this in the past is guaranteed to behave in the same way with any paint, be it polyurethane or oil, thus reducing the expected life of the paint. When cracks begin to appear in the coating, it loses its integrity, begins to let water pass under it and no longer fulfills its function.
If the goal is to achieve maximum life from polyurethane paint, it should only be applied to a wooden boat that is not subject to bending deformations - this can be a well-sheathed hull in perfect condition, a boat with slatted sheathing and resin-glued seams, a hull with plywood, with a diagonal sheathing or pasted over with fiberglass.
Wedge-shaped skin grooves, left open and filled with putty, are the most likely place for the development of shear deformations even on the strongest hulls. Not all owners of this kind of grooves provide aesthetic satisfaction, but if they are there, then this is only for good. Unfortunately, these V-grooves hide the incipient microcracks in the coating, which are much less noticeable with them than on the body, in which adjacent boards are joined flush.
Connection density. wooden case must be carefully examined to ensure that all end and shoulder joints, grooves and cracks are tightly sealed and that water is prevented from entering the load-bearing elements hull structure, where it can penetrate along the gaps and along the fibers of the wood. Nothing breaks down a paintwork faster than soaking water, and often this process goes unnoticed by naive wooden boat owners, who end up with unsightly blisters of paint where water has penetrated below the surface. The polymer film resists this no more than ordinary oil enamel, in fact, it is even more vulnerable, because the moisture from the inside, trying to get to the surface, is not able to pass through the impermeable polymer film, as is the case with a less dense film of enamel coating. Therefore, moisture tends to tear off the film from the surface, forming a bubble in this place.
About security
Polyurethane and epoxy coatings, as a rule, contain more toxic components in their composition than conventional enamels. The latter should also be treated with some caution, because manufacturers are constantly working on improving them and modern enamels may contain primers, solvents and thinners that are just as toxic by inhalation or contact with the skin as those that we find in polyurethane paints. materials. Epoxy compounds, as everyone knows, contain many components that can cause skin allergies and other reactions. Contact with the skin should be avoided and only work in respiratory protection - at least a tight-fitting respirator with fresh activated carbon filters.
When applying polyurethane paints from a spray gun, the isocyanate component of polyurethane turns into an aerosol and can easily enter the human lungs. When painting with a brush, this process is not so pronounced, since the large molecular weight of the isocyanate does not allow its molecules to actively evaporate. Regardless of the chosen method of application, a person when working with polyurethane paints is exposed to the strong and toxic solvents contained in them, which easily evaporate and end up in the lungs. Need personal protective equipment.
When working on outdoors necessary protection can provide charcoal filter respirator. If you are the owner of a beard, you should understand that it will be difficult to achieve a snug fit of the mask and this kind of respirator will not provide you with adequate protection. When working in close contact with polyurethane, if you have a beard or if you need more reliable protection, you should use a respirator with overpressure and air supply from outside. You must wear a respirator and gloves while mixing, applying paint and cleaning from its chemical components. If at some point you smell paint in the respirator, the concentration toxic substances airborne poses a hazard and action is required. Remember to read the MSDS for all chemicals you use, and don't limit yourself to reading only what the label says.
Application of polyurethane paints
Polyurethane coatings are thin, durable and high gloss coatings that only look their best when applied to perfectly smooth surface(it doesn't matter if it's paint or varnish). Even the smallest hair-thin scratches will show through the film. Therefore, the preparation of the surface for painting is no less important than the painting process itself, which, in turn, proceeds differently for paint and for varnish.
If the boat's old enamel finish is undamaged and in good condition, it is an excellent base for polyurethane paint and only needs to be sanded to 180 grit, sanded to a high gloss, and primed with polyurethane primer before painting. The condition of the existing pavement should be assessed very critically. If the enamel is not in very good condition, you can achieve much better results by removing all existing paint to bare wood and starting from scratch.
There are two well-known surface preparation methods, both involving the application of epoxy over bare wood. The first way is to use any decent water-resistant, filler-free epoxy such as ChemTech, ColdCure, Detco, System3, Travaco, or West System (named in alphabetical order) to protect the wood and fill its texture. Two or three layers of it can be applied with a roller, then treated with coarse sandpaper and washed according to the manufacturer's recommendations. This will be the basis for the soils applied subsequently.
As an alternative way clean surface wood can be covered with several layers of epoxy primer using a brush, roller or spray gun (if you have one and you have experience in using it). Soil layers are applied and ground one after another until all depressions and dips are filled flush with the surface. Epoxy resins applied in thick layers are very durable and difficult to sand, but it is this feature that makes it possible to harden the surface of the wood and reduce its susceptibility to impacts and scratches. Think carefully before using epoxy primers, which are easy to sand and have very low impact resistance. A simple thing to remember is that what is easily sanded will be just as easily susceptible to dents, and the hardest surface to process will have the greatest strength.
When applying epoxy primers with a roller, a surface covered with a noticeable pimply texture is obtained, which is quite difficult to sand smoothly. In this situation, the spray gun in several passes would significantly save time. The soil will level itself out and required thickness recruited in a shorter period of time.
After the surface of the wood is reliably protected (and epoxy resins perform this function best), the next step should be to putty the surface. Putty for this can be prepared by yourself from epoxy, microspheres and aerosil, applying it with a spatula. You can also use factory-made low-density putties.
When the puttied areas have been sanded, sanded and there are no noticeable depressions, the entire sanded surface should be recoated with epoxy primer to close the pores of the microspheres destroyed during sanding. After priming with a roller, brush or spray gun and subsequent drying, the surface should be treated with sandpaper with a grain of 100-150.
Epoxy primers to improve the pouring on the surface contain solvents in their composition, which, as the composition cures, evaporate from the drying film. When solvents evaporate from the surface, the coating film shrinks, and this process continues until they are completely evaporated. Therefore, do not rush to grind a thick layer of epoxy primer (especially in cold weather), and even more so if several layers have been applied without waiting for the solvents to completely evaporate from the previous layer.
Epoxy putties containing fine fillers (such as Interlux Red Hand) can also be used to seal remaining wood pores and minor scratches. The surface after them is treated with a sandpaper with a grain of 150-180.
I do not recommend using it for repairing surface defects. wooden boat automotive polyester putty. Polyester resin is a water-absorbing material, and these putties are very porous and contain a significant amount of solvent in their composition, they tend to shrink and swell when the ambient humidity changes.
Even now it is still too early to start applying paint. It's time for the finishing ground. I prefer to use Sterling U-1000 polyurethane primer for this purpose, diluted to the desired consistency depending on the method of application (brush, roller or spray gun). It is a quick-drying polyurethane, it is sufficiently elastic, has excellent adhesion to all types of surfaces and is perfectly sanded. It should be applied in a smooth layer suitable for finishing sanding with grit 220.
After finishing sanding, the quality of the prepared surface is checked by rubbing it with the fingertips - the touch should not reveal tangible defects. Perfect coverage you need the perfect foundation.
And now, finally, everything is ready. The pigmented paint base is mixed with a catalyst, usually a small amount of accelerator is added to them to speed up the film curing. The accelerator also avoids gloss haze, which can occur when working outdoors when an incompletely cured surface comes into contact with high humidity.
After mixing, allow the paint 30-45 minutes for the reaction to start and the formation of the polymer structure to begin. This will help the coating film behave in a more predictable manner once applied to the surface.
After this time, a thinner is added to the paint, the amount and grade of which depends on the climatic conditions and the method of applying the paint (brush or spray gun). It is necessary to dilute the paint, otherwise its poor bottling is guaranteed. Excessive addition of diluent does not achieve desired thickness film and shortens the gloss life of the paint in the future.
To work, use a good brush - not necessarily the most expensive, but a combination of hog bristle and ox hair such as Corona, Redtree, Linzer, or more expensive Hamilton, if you want. Always keep a few of them in stock, because most likely one case will not do.
Brushes should be thoroughly cleaned immediately after use, then rinsed and scraped or wire brushed to remove all traces of cured paint. The brush should be rinsed several times in solvent with wringing out after each time. As a rule, after two days of use, the brush is no longer suitable for applying a top coat due to the accumulation of cured paint near its holder. Set it aside - it may still be useful for applying primers.
Working on painting large areas such as deckhouse walls and sideboards, we have found that phenol-coated foam rollers (for solvent protection) are the ideal tool for applying polyurethane paint. One person using a roller rolls an area from edge to edge vertically and 30-45 cm horizontally, moderately dipping the roller and distributing the paint in a thin layer. His partner with a brush immediately follows and flutes the surface with two or three movements in the vertical and horizontal direction. Some argue that the last movement of the flute should be vertical, as this results in fewer sags and streaks. Others follow a more traditional technique, swiping the flute one last time in the direction of the board line. It seems to me that with the final vertical movement of the flute, smudges are still better eliminated. In the course of work, if the paint begins to seem inert to you, it may need to be further diluted, as in the case of brushing with ordinary enamel.
After the first pass of the entire surface and spraying of the tie coat, the coating should have a good gloss without cloudiness. Paint should be applied so much that when poured it gives a beautiful mirror surface. Many materials, when applied in a layer of this thickness at one time, quickly form streaks.
It is necessary to wait until the first layer of paint rises to the state of "tack free" (from half an hour to an hour), and then apply the second layer. It should also be of such thickness that a few minutes after application, the paint surface stretches and acquires a beautiful gloss. Two passes of the spray gun will usually achieve sufficient coating thickness.
Various decorative stripes can be applied to the painted surface once the paint has hardened enough to not be damaged by masking tape. This is usually possible as early as the next day after painting, although in colder climates it may take longer.
Cleaning of tools is easy with MEK solvent, do not forget about gloves and a respirator.
Application of polyurethane varnish
We have vast experience in applying polyurethane varnishes in all situations, and my advice reflects some important fundamentals gained through years of experimentation and failure.
As with paint, our goal is to achieve a continuous film on a hard, dry surface. However, in the varnish situation, the effect of solar radiation on the wood must also be taken into account. It is best to cover with polyurethane already existing lacquer coating sufficient thickness. The amber-colored particles and UV inhibitors contained in the varnish protect the wood surface from damage. By itself, the varnish does not have sufficient hardness, its surface is easily scratched and quickly becomes cloudy under the influence of the sun. In contrast, polyurethane is hard, has a high gloss and is very scratch resistant. It will protect the varnish and combine the beneficial properties of both coatings. This combination, according to our observations, extends the life of conventional varnish by at least 4-5 times, and we are talking about regions such as Florida, Southern California or the tropics.
After a film of ordinary varnish of the required thickness has been obtained on the surface of the wood, which makes it possible to hide surface defects (usually about eight layers), let the last layer dry and harden. Sand the surface with 220 grit sandpaper and coat it with two to three coats of clear polyurethane varnish, preferably within two to three days, one coat per day. Before applying the next layer, the surface is polished only to remove adhering dust particles and eliminate minor defects. The lacquer film does not have chemical resistance for at least 48 hours after application, so if the next coat of lacquer is applied in this time interval, it is not necessary to sand the entire surface. If more than two days have passed since the application of the polyurethane varnish, the surface should be carefully sanded until the gloss is completely eliminated.
In a similar way, we have successfully covered teak, oak, spruce, pine, cedar, pink tree, padauk, eucalyptus, ash and many other types of wood. Inside the case, where there is no UV radiation, polyurethane varnish can be applied directly to the surface of the wood, which allows you to create an almost indestructible "armor" on the surface. wooden decking, lockers, galley and in many other places subject to intense wear.
Due to the fact that there is nothing easier than to clean the glossy surface of polyurethane, we have tried to coat it (with indispensable success) holds, engine compartments and polished brass parts. Polyurethane varnish has proven itself in the form protective coating epoxy resin on hulls with laminated diagonal skin. Polyurethane reduces the oxidation processes in the epoxy resin caused by solar radiation and its chalking.
Care and repair
The surface painted with linear polyurethane is easy to care for - wash it from time to time with soap and water. Stubborn grease, oil, paint from the sides of other boats, buoys and moorings can be easily removed from the polyurethane surface with strong solvents without harming the polyurethane film.
Watch closely for any cracks or dents in the coating where water can enter and repair them immediately. Remember - in no case should water penetrate under the film.
After the end of the whole heartbreaking story with painting, the inevitable is still destined to happen. A collision with a buoy, the actions of a careless helmsman or the formation of a bubble lead to the fact that the brilliant appearance of the boat gradually ceases to be the center of everyone's attention.
A small scratch or chip can be repaired by mixing a small amount of a pigmented paint base with a catalyst. Let it stand for about an hour after mixing so that it acquires a thicker consistency. Then take a small brush and use it to fill in the defect. If necessary, repeat this procedure several times until the scratch is filled flush with the surface.
More significant scratches can be repaired by professional painters who own a spray gun. In this case, the place of repair will hardly differ visually. Repair of the damaged area is carried out (preferably) using epoxy putty, the surface surrounding the area is sealed for protection. The surface is primed very thin layer from an airbrush, polished and painted. If you do not paint the entire open area up to the sealed border, you can avoid an unsightly transition. After a couple of days to dry the surface, dry particles of aerosol along the perimeter of the area are lightly sanded with 1500 grit (dry or wet), then polished with the finest polishing compound, and finally with Plexiglas polish. After that, the surface becomes almost perfect.
The owner can repair the damaged area with a brush on his own. In terms of its level, it will look approximately like a repair using ordinary enamel paint and will not be as subtle as the professional method described above. I have had the best results by working the perimeter of the freshly applied area with a dry brush, trying to smooth it flush with the old one as much as possible. When done correctly, these sorts of patches are barely noticeable from a few feet away.
Is there any benefit to this?
If the boat was in good condition, and the preparation, painting itself and subsequent care were carried out correctly, the polyurethane coating can last you 3-5 years. During this time, the painted surface will be easier to clean and more resistant to scratches and abrasion than conventional enamel. Dirt, oil and fuel will stick to it much less, and the color will remain brighter and more vibrant. Losses in the form of twice the cost of painting are turned into gains in the third year, even if only the cost of materials is taken into account.
We all know how laborious the process of raising and painting a boat can be, so after only two years, polyurethane paint system starts to pay for itself. The difference in labor costs when priming and painting with polyurethane over a strong existing coating is quite small compared to conventional enamel. If you start everything from scratch, i.e. from bare wood - the cost of painting will undoubtedly be more expensive. However, given that over the next ten years the boat will only have to be repainted once or twice, it is easy to calculate the savings. Therefore, do not get depressed from calculating the cost of the materials needed for this, take into account the potential of polyurethane.
The union of wood with polyurethane may be the best combination. The result of the work is absolutely magnificent and far exceeds the traditional "yacht" enamels in terms of durability. This is my opinion about packing wood in "plastic".
Number of impressions: 6132
Availability and high quality, as well as a wide range of- that's what made the varnish for real available material. But many home and private masters are still asking the question - what to do if the varnish has dried up? There are no hopeless situations, and therefore there are several ways to solve this issue.
It may seem that these concepts are identical to each other. But this is a misconception. How to dilute the varnish if it has thickened, and what else can be done in this case, because this situation happens quite often? Use special means belonging to one of two categories:
Some tools are effective when performing only one function. So, for example, white spirit is suitable for diluting such compounds:
- oil;
- alkyd;
- belonging to the polyurethane group.
At the final hardening of the varnish, white spirit cannot be the solution to the question of how the varnish can be diluted. Therefore, we have to look for other options. The so-called methylated spirits equally help to dissolve the varnish, and simply get a diluted composition.
On the video: the differences between thinners and solvents for varnishes.
How to dilute polyurethane varnish?
Polyurethane is a modern polymer. In terms of the totality of its properties, it surpasses such analogues as metal and rubber, plastic and rubber. In production, polyurethane is mixed with other chemical additives, and therefore does not allow the base to dry out.
There are polyurethane compounds, which are based only on water. Such chemistry is environmentally friendly, characterized by the absence of harmful emissions.
If it is necessary to make a liquid polyurethane composition, then the use of such substances is permissible:
- eluents that are of types P-4, P-5;
- acetone;
- xylene;
- toluene.
What about alkyd options?
These products are distinguished by such properties as strength, ability to resist impact ultraviolet rays and moisture in large quantities. The high level of adhesion (adhesion to the surface) is also pleasing.
The main component of alkyd compounds is an organic solvent.
Dryers and other substances are added to it, giving additional performance characteristics. But different compounds can be used as the main component:- mixtures of resins on alkyd and melamine-formaldehyde bases;
- glyptal resins, to which cottonseed oil is added;
- pentaphthalic resins, revitalizing them is quite simple.
How to dilute alkyd-based varnish? Try white spirit - this is a fairly traditional and effective material.
About bituminous varnishes
In this case, the basis is a mixture consisting of various resins and oils, as well as bitumen of a special grade.
If after application the material is already dry, it forms a strong black film on the surface.
It is a moisture resistant compound that is immune to chemical attack of any kind. In domestic use, bituminous materials have become common not so long ago, but have already become known for their low cost. Often such a composition is used as a protective layer against corrosion. To prevent the varnish from drying out, apply standard protection.If there is a wooden base, but it is not necessary to emphasize the natural texture, choose varnishes from bitumen. They are also able to give the surface the effect of aging, and do not go from normal to liquid.
To unique features includes the use of so-called cold gluing. If the solution has thickened, you can give preference to white spirit. It is important to use airtight containers, then during storage you will not need to worry about the appearance of a thick and dried varnish. In the storage place itself, it is important to maintain the absence of light, moderate temperature and humidity levels.
How to remove dried varnish from tools
The above listed ways that help improve the consistency if the varnish has thickened. But what needs to be done to get rid of varnish on painting tools, and is it possible to remove synthetic compounds after they've been applied?
What to do if the varnish has thickened, and how to dissolve a fairly old composition? Alas, this is not possible in this case. Scraping or grinding will help get rid of the problem if it is at least partially eliminated. In case of refusal mechanical way processing solutions are selected individually.
The use of so-called washes is one of the easiest options for solving the problem.
This substance is a chemical mixture. Available in the form of powders or gels, as well as in the form of a liquid. Acetone is able to cope with the simplest varieties of varnishes. Denatured alcohol will help remove shellac. How to restore it is another question.
Here is how to perform the procedure for removing varnish from tools in stages:
- Apply solvent to the base surface.
- Wait until the film on the surface begins to soften.
- The treated surface can be covered with polyethylene to speed up the process.
- The old composition begins to swell and darken, after which the exfoliated particles can be removed.
The spatula facilitates the process of getting rid of varnish in a softened form.
The main thing is to work carefully so that the surface itself is not damaged. If the composition dries, the work will have to be suspended. Otherwise, there is a risk of defects on the surface, which will then be difficult to get rid of.To remove the remnants of varnish from painting tools, you can use the following tips:
- Prepare a warm solution of water and soap. This option is suitable for water-based varnishes.
- For other paint materials with organic basis it is better to use white spirit, kerosene or turpentine. Rinsing out the remnants of the substance will not be difficult. Then it remains only to rinse the instrument itself with some kind of chemistry.
Dilute nail polish is also simple: to do this, you need to lean the vessel with the composition against the battery or lower it into warm water for a few minutes. Now you know how to dilute the varnish. For this, several different means, then it will be much easier to breed the composition.
Solvents for dried varnish (2 videos)
Varnishes and solvents (22 photos)
What is polyurethane varnish for wood?
Products from natural wood have enjoyed great success over the years. It is no secret that natural material needs reliable protection, as it is afraid of moisture, is not resistant to technical fluids, and hardly resists natural atmospheric influences and mechanical damage.
For maximum reduction negative consequences, wood products must be treated with various chemical formulations. And polyurethane varnishes become one of the the best helpers in this case.
Varieties of polyurethane varnishes
The most common two-component polyurethane varnish in use, modern manufacturers offer just such a composition.
In the case of one-component polyurethane varnishes, everything is very simple. In order to use them, you do not need any additional preparations. Such varnish consists of several independent components. There is an opinion that the use of two-component products is difficult, but this is not so. Before applying it to the surface, you just need to mix the base and hardener together well in certain proportions. The correct proportions are almost always indicated by the manufacturer on the packaging or in the instructions. Therefore, there are no problems.
According to the degree of gloss (gloss), the varnish is divided into:
- glossy;
- matt.
Benefits and advantages
Deciding to choose a polyurethane varnish for natural wood, you get numerous benefits:
polyurethane varnish coating creates reliable protection from negative mechanical impact, dirt, grease, dust;
- varnish increases the life of any product, even if they are subjected to regular and intense loads. An example is the parquet floor of the corridor;
- polyurethane coating has an increased level of abrasion resistance;
- a product on which a layer of varnish is applied receives the best aesthetic performance. The amazingly beautiful and original structure of natural material is not hidden by a layer of opaque material, because such a varnish is highly transparent;
- elasticity. Thanks to its special consistency, it is easy and simple to apply polyurethane-based varnish on wood, even if the product has a complex configuration. In the case of moderate deformation, cracks will not appear on the treated surface. In addition, the composition has good adhesion, and will not flake off.
Terms of use.
Before using polyurethane wood varnish, you need to carefully prepare the wood surface. To do this, you must rid it of pollution and sand it. The polyurethane varnish itself is applied using a spray gun. Much depends on how large the surface to be treated is. Taking into account the chosen method, the desired consistency of the product is also selected. In certain situations, the composition is diluted with a synthetic solvent.
Two-component polyurethane varnish requires compliance own rules. One of the most important says that it is necessary to observe the proportions when mixing very strictly. If you do not pay attention to the recommendations of the manufacturer, which he indicated in the instructions, then as a result the mixture will not harden, crack or fall off. The finished mixture has a limited life, after mixing, the polymerization process occurs. If the finished mixture of varnish and solvent dries, then it cannot be diluted, polyurethane varnish is irreversible.
Always prepare as much composition as you need to apply at one time. No need to stock up on wood varnish, preparing it for future use.
The number of necessary layers is different, and depends on how it will be used in the future. wood material. But the general recommendation is that you do not need to save the composition, and apply less than two layers. Before applying a new layer, you must wait. How? You can find this information in the instructions for the product. You don't have to give up on the rules.
In order to mix a two-component polyurethane wood varnish, use the special container in which it was sold to you. Make sure that all the remains of the second component fall into the container to the first to the maximum. you can break correct proportion composition, if a lot of mixture remains on the walls and bottom of the jar. The disturbed proportion, in turn, will lead to the fact that all characteristics and operational properties varnish will deteriorate.
Before you apply polyurethane wood varnish, you need to mix it well. Make sure that there is a positive temperature in the room during processing. The drying period of the top coat in most cases is approximately 7-8 hours.
How to choose?
The purchase of protective compounds for wood processing can always be called important process. After all, the cost of wood has remained high for many years. If you do not know how to choose a polyurethane varnish, start from what properties it should have and what qualities are most valuable to you. For example, if you decide to purchase a composition for applying it to the floor, then decide in advance on the intensity of future loads. In case of flooring, which is not intended for large crowds, you can choose a polyurethane wood varnish that does not have a high degree of protection. If you want to treat a floor that will be used for “mass gatherings” in the future, and which is quite likely to be constantly and heavily soiled, choose products that have the maximum degree of protection and abrasion resistance.
Any polyurethane varnish for wood has good adhesion. It is resistant to chemicals. But if you want to get the maximum, then choose two-component formulations. They are distinguished by the best indicators in terms of strength and elasticity.
If you cannot choose a polyurethane varnish for wood on your own, just contact the Europroject-Center sales consultants for help. You can also read the information in the catalog on the site site.
However, we would like to say that this product is in any case high-class and high-quality. If you select an item from well-known manufacturer Sayerlack, who cares about his reputation, you will always achieve the desired results. But if you try to save money, then in this case you can become the owner of low-grade products. Choosing a polyurethane varnish for wood is not as difficult as it might seem at first glance. The cost of production is affordable and low, and therefore savings are simply inappropriate here. The Europroject Center company offers a wide range of Sayerlack two-component polyurethane varnishes for wood.
Parquet chemicals are a group of products used to protect and decorate wood floor, wall and ceiling coverings. This includes varnishes and paints, primers and putties, stains and tints, adhesives, antiseptics, solvents and thinners. A large number of Store-bought wood varnishes are in most cases a liquid, ready-to-apply mixture. The question arises: is it possible, and how to dilute the varnish, if it is too viscous?
When diluting the varnish, the main thing is to perform the correct proportions.
To answer this question, several factors must be taken into account. First, we turn our attention to the key composition of the mixture. Second, select the desired solvent. Third, when mixing, we observe proportions so as not to reduce the quality of the material. Let us consider in more detail how thickened varnish can be diluted and how to do it according to the rules? And also, what to use to remove the old coating with a protective effect from wood and what is the care of the tool?
Dilute, dilute or dissolve
At first glance, there is no difference. With the help of a special tool, we bring the lacquer substance into a “working state”. A solvent is a liquid that dissolves the dried varnish, bringing it from a solid to a liquid state. We use a thinner if it is required to correct (reduce) the viscosity of paints.
Certain types of organic eluents serve two roles, but some may be effective in one task and completely useless in another. So, for example, compositions of polyurethane, alkyd and oil groups can be diluted with white spirit. However, if the varnish has dried up, it will not work to dissolve it with white spirit.
With the help of white spirit, you can dilute certain varnishes
But shellacs, on the contrary, equally dissolve and dilute with denatured alcohol. However, we will not go into such subtle details.
If you need advice on how to dilute the varnish or what to use to dilute the paints, it is better to consult with specialists.
Polyurethane blends
The composition of polyurethane-based varnishes, paints, primers, adhesives and others contains polyurethane - a modern polymer material. The combination of its parameters surpasses such famous materials as rubber, plastic, rubber, metal. To obtain paint and varnish and adhesive solutions of high strength, in commercial production it (polyurethane) is mixed with special chemicals.
A lot of varnishes are made on the basis of polyurethane and on the basis of water. This chemistry for parquet is environmentally friendly and non-toxic.
If it is necessary to make the substance more liquid, you can use as a diluent for polyurethane-based compositions:
- toluene;
- xylene;
- acetone;
- eluents like R-4, R-5.
Acetone - modern facility for thinning polyurethane-based varnishes
Alkyd mixtures
At alkyd compounds good adhesion, moisture resistance, insensitivity to ultraviolet radiation, reliability. They can be used for indoor and outdoor work. In alkyd mixtures there is a main element, organic solvents, driers (for quick setting), additives. The key element could be:
- pentaphthalic resin;
- glyphthalic resin with cottonseed oil;
- mixture of melamine-formaldehyde and alkyd resins.
To enhance the parameters of materials, parts of alkyd resins are often included in the composition of multicomponent varnishes, paints, and enamels. The classic diluent here is white spirit.
Bituminous mixtures
Bituminous varnish is a mixture of specialized grade bitumen, a variety of resins and oils. After drying, a strong black film will appear on the surface, moisture resistant, insensitive to chemicals. It is considered quite new in domestic use material. Belongs to the category of inexpensive. It is more commonly used as an anti-corrosion layer for protection.
For wooden surfaces it is used when it is not necessary to highlight the natural texture of the base (instead of paints). bituminous material found a use in the form decorative coating for the effect of surface aging (patina). Another original characteristic of bituminous mixtures is cool gluing. The bitumen-based solution is diluted with white spirit.
So that it does not thicken during storage, the container must be airtight. The storage place should be dark (without direct sunlight), with moderate temperature and humidity.
Bituminous varnish very reliably protects the surface from moisture and chemical influences, diluted with white spirit
Yacht varnishes
Yacht (or yacht) varnish is considered one of the very effective means of protecting the surface of natural wood. Already from the name, the specifics of the sphere where it is used are clear. In addition, the yacht composition is perfect for woodwork outside and inside any objects (not only boats, boats, yachts). It is insensitive to manifestations of moisture, temperatures, aggressive environments.
Yacht varnish. Important Features:
- high degree of protection of wooden structures;
- physical and mechanical immunity to environmental influences;
- durability, increase the service life of wood.
To achieve such results, poisonous chemical elements (toluene, xylene) are used during the manufacture of the material. There are several production technologies:
- alkyd yacht (based on organic solvent white spirit);
- urethane-alkyd yacht (eluent is the same, but in smaller quantities);
- alkyd-urethane yacht (dissolving additives have strong volatility);
- acrylates (compositions based on water).
Dilutes yacht varnish with white spirit, no more than 5% of the total volume. The solvent acts on the substance only fresh. After drying, the lacquered flooring of the parquet will become resistant.
Lacquer for yachts, boats, boats has a high resistance to wear and is also diluted with white spirit
How to remove dry polish
Above, for the most part, are listed ways to improve the consistency if the varnish has thickened. And what needs to be done to remove varnishes and paints from painting tools? Can the synthetic material be removed from the wood after application?
It will simply not work to remove outdated furniture or parquet varnish from the surface of the tree. In most cases, where it is realistic, scraping or grinding is used. For non-mechanical removal, the type of solvent is selected personally. Takes into account the key composition and Chemical properties varnishing.
The easiest way to remove already unsuitable parquet flooring with a protective effect is to use a specialized remover. The substance is a chemical mixture. You can use liquid, gel or powder. Acetone copes with the simplest types of paints and varnishes. Denatured alcohol is more suitable for removing shellac.
First, a liquid, gel or powder is applied to the varnish surface. Then you need to wait for the softening of the film. To speed up the process, it is recommended to cover the finished surface with polymeric ethylene. Over time (from 40 minutes to 4 hours), the outdated varnish will begin to swell, darken. What to do next?
To remove softened varnish, it is more convenient to use a spatula. It is necessary to work carefully so as not to damage the surface of the wood. What to do if the old protection coating was not completely removed the first time? If necessary, finishing can be repeated.
To remove the remains of a substance from painting tools, the following are used:
- With a warm water-soap solution, water-based parquet varnish is washed off freshly;
- White spirit, kerosene, turpentine are suitable for many organic solvent based paints. The remains of the substances are perfectly rinsed out, then the instrument is washed with some kind of household chemical and rinsed well in water.
When choosing the type of eluent for diluting paint and varnish mixtures, the main thing is to carefully study the composition, and also use the manufacturer's advice indicated on the package.
You need to remember about personal protective equipment, especially if you have to work with strong-smelling, quick-drying compounds. Ventilation of the room during and after work will protect against poisoning by toxic fumes. Keep these materials away from children.
Solvents are often used to dilute paints and varnishes (paints, varnishes, enamels, glue). They are of all kinds. And each of them has its own characteristic properties. In this article, we will describe in more detail what a solvent is for acrylic paints, oil paints, varnish, glue.
Acrylic thinner
This composition is often used to dissolve polyurethane resins, two-component acrylic paints, primers. Although acrylic paints can be thinned and plain water, the use of this solvent significantly speeds up the process when the coating layer dries. In addition, its use allows you to achieve a flat and smooth surface to be painted without the formation of any smudges and white-milk plaque.
Solvent for acrylic has the form of a clear liquid with a specific odor. It is produced in several versions that differ in drying time (slow, medium and fast). And they are used in certain conditions, depending on humidity and air temperature. For example, in cold weather it is better to use a composition with a high evaporation rate. On a hot day, on the contrary, it is desirable to use a solvent with a low level of evaporation.
It is desirable to store the composition in well-ventilated, cool and dark rooms (without UV rays access to packages). It is also important that the basic norms and standards are valid in it. fire safety. The packaging itself must be tightly closed and in an upright position.
Thinner for oil paints
The following solvents are often used to dilute oil-based paints: white spirit, gasoline, acetone, turpentine. Let's talk in more detail about each of them. So, white spirit - is produced in the process of oil distillation. It is used to dissolve alkyd, bituminous, oil paints, as well as for rubbers, drying oils, epoxy esters and polybutyl methacrylate. Instead, nefras 150/180 can also be used (as a substitute). Turpentine - is manufactured industrially during the processing of pine wood.
The following types are distinguished: dry distillation, steam, sulfate, extraction. The best is the one that contains more pinene. It is used to dilute oil paints, glyphthalic, bituminous, pentaphthalic coatings. Acetone - taught by processing cumene hydroperoxide. it good solvent varnishes and paints based on vinyl polymers. It is also used to dilute polyacrylates, epoxy resins, chlorinated rubber, vinyl chloride copolymers.
Solvent for glue moment
The adhesive solvent is necessary not only in the process of applying the composition, but also when the mixture has already dried. For example, there are times when you need to detach some parts or wipe off a stain. The best solvent for superglue, these are usually ethyl acetate, xylene, butyl acetate and acetone. Thinners for acrylic and polyurethane varnishes and paints are also sometimes suitable. Let's talk about them in more detail. Ethyl acetate - used for nitrocellulose and polyacrylate paints and varnishes. Like acetone, it can dissolve almost all polymers.
Solvent xylene - consists of a mixture of isomers, which is obtained from coal or oil. Therefore, it is divided into stone and oil. It is used for phenolic, alkyd, chlorinated rubber, bituminous, epoxyphenolic paints and varnishes. Butyl acetate - made by heating acetic acid and butyl alcohol with the addition of catalysts. It is used to dilute oil esters, chlorinated rubber, fats, cellulose. And if you add a small amount of butyl alcohol to it, then it is able to prevent the formation of a coating film.
Solvent for varnish
In order to dilute the varnish, the following solvents can be used: benzene, R-4, R-4A, 646. If we talk about the first one - benzene, then it is obtained by pyrolysis of crude stone benzene and oil. It is an excellent thinner for rubbers, fats, oils, waxes, cellulose, esters, silicone and cresol-formaldehyde resins. In the event that you need to dissolve the polyurethane varnish, then the compositions R-4 and R-4A are also well suited.
The main ingredients of these mixtures are: ethers, ketones, hydrocarbons. And also the composition includes some components that can significantly increase the efficiency of dissolving paintwork materials. They are used for many paints and varnishes - varnishes, fillers, primers, enamels. 646 solvent is suitable for surface treatment before applying coatings (degreases it), and also effectively dissolves nitro enamel and nitro varnishes.
