The basis of polyester varnishes is made up of resins containing molecules of unsaturated polyesters capable of polymerization reactions with unsaturated monomers (styrene, allyl alcohol ethers, allyl ethers, etc.).
Polyester maleate, a polycondensation product of ethylene glycol, maleic and phthalic anhydrides, is most often used as the basis for polyester paints and varnishes. The phthalic anhydride molecule contains an aromatic ring, which improves the compatibility of the resulting polyester resin with aromatic solvents - monomers (for example, styrene). The presence of an aromatic core provides increased performance properties of coatings, giving them heat resistance and hardness. Coatings based on polyester maleate are characterized by significant fragility, therefore, to increase their elasticity, aliphatic dibasic acids (adipic, sebacic, etc.) are added to the varnish base, which do not participate in the polymerization reaction, but only improve the properties of the coating.
Paraffin-containing (PE-246, PE-265) and paraffin-free (PE-232, PE-250, PE-250M, PE-250PM) polyester varnishes are produced.
Paraffin-containing varnishes contain styrene as a solvent monomer, which has a fairly high ability to evaporate. A decrease in styrene content can negatively affect the polymerization reaction of the varnish, since it takes part in it. In addition, atmospheric oxygen is able to interact with free radicals of styrene, forming styrene peroxy radicals, which contribute to the termination of the molecular chain formed during the polymerization process, and thereby slowing down the curing process of the coating. To protect styrene from volatilization and the inhibitory effect of atmospheric oxygen, paraffin (styrene solution) is introduced into these varnishes, which dissolves well in polyester resin and is easily released from the material (floats), forming a protective film on the surface. Due to this, the varnish base almost completely interacts with the solvent monomer (styrene), as a result of which the content of film-forming agents (dry residue) in these varnishes is very high (90 ... 95%) with a low initial viscosity.
The technological process of finishing with these varnishes includes operations of refining the coatings (grinding and polishing), which significantly lengthens the finishing cycle and increases labor costs (by about 40%). Paraffin-containing varnishes are used mainly for finishing flat panel elements using the pouring method. Their use for finishing assembled products or product elements located at an angle to a horizontal surface is hampered by the varnish running off and the impossibility of grinding and polishing.
Paraffin-free varnishes are a solution of poly-firmeleinate in TGM-3 ether (triethylene glycol dimethacrylate ether), which is less volatile and less reactive than styrene. Therefore, a protective film is not required for polymerization.
Curing of polyester paints and varnishes occurs as a result of the copolymerization reaction of unsaturated polyester and solvent monomer, which occurs through the mechanism of chain radical polymerization.
To initiate the polymerization reaction of the polyester resin with the monomer solvent, initiators (hardeners) are introduced into the varnishes. Peroxide and hydroperoxide compounds (benzoin or cyclohexanone peroxide, isopropylbenzene hydroperoxide) are usually used as hardeners. All these compounds contain an oxygen bridge R-0-0- R. The valence bond between two oxygen atoms is fragile and decomposes under the influence of temperature into free radicals R*, which play the role of active centers of the polymerization reaction. Thus, hardeners initiate the polymerization reaction and take part in it.
When a monomer molecule interacts with a free radical formed during the decomposition of the initiator, the monomer receives the amount of energy necessary to begin polymerization: R*+ M→R –M*. In this case, one act of initiation can cause numerous sequential reactions of addition of the monomer to the active radical:
R–M*+M→R–M–M*;
R –M –M*+ M→R –M –M+M*;
R –М n –M*+M→R–М n +1 –М*.
As a result, polymer chains with loose bonds arise that can react with unsaturated polyesters.
Organic peroxide compounds with a relatively high decomposition temperature (70...100°C) are used as initiators, which ensures a sufficient shelf life at normal temperatures for the semi-finished varnish solution with a hardener.
To ensure the decomposition of peroxide compounds without heating, accelerators are used, which form an oxidation-reduction system with them, as a result of which the decomposition of peroxide compounds occurs at normal temperature and the polymerization reaction of the varnish begins. Thus, accelerators only provide acceleration of the onset of the polymerization reaction, but do not take part in it. As accelerators, salts of heavy metals of variable valence (cobalt, vanadium, manganese) soluble in hydrocarbons are used, which play the role of reducing agents in this system. As accelerators for polyester varnishes, a solution of cobalt naphthenate in styrene (solvent No. 30) or toluene (solvent No. 25) and a salt solution based on vanadium pentoxide in monobutylphosphoric acid (solvent No. 31) are usually used.
During redox initiation, rapid decomposition of hardeners occurs, as a result of which the concentration of free radicals increases and the polymerization process proceeds quite vigorously at normal temperature. The reaction is exothermic, accompanied by the release of heat, and the larger the layer of varnish, the more heat is released.
The molecules of polyester resins that form the basis of polyester varnishes contain several groups with a double bond, due to which, during copolymerization, cross-links are formed between linear chains, branching increases to form a polymer of a three-dimensional structure with high strength properties.
The progress and completeness of the polymerization reaction is greatly influenced by the ratio of the introduced hardener and accelerator. For each system there is its own optimum of this ratio. If the amount of hardener is insufficient, copolymerization of the monomer with the unsaturated polyester occurs to an incomplete extent; an excess of hardener leads to a sharp decrease in the bonded monomer. With a low amount of accelerator, the formation of free radicals slows down and thereby reduces the intensity of the polymerization reaction. However, with an excess of accelerator, a large number of active radicals are rapidly formed, which leads to the simultaneous appearance of a significant number of macroradicals that interact with each other, the disappearance of free radicals and chain termination.
Schematically, the curing process of polyester varnishes can be represented as follows. A few minutes after applying varnish solutions containing a hardener and accelerator to the surface of a furniture panel, the viscosity increases sharply, the coating loses its fluidity, and gelatinization occurs. The duration of this process depends on the composition of the varnish and the ambient temperature and on average ranges from 15 to 40 minutes. With further exposure, the coating is completely cured.
To accelerate the decomposition of the initiator and the hardening of the polyester layer, in some cases special additives are used - promoters (dimethylakiline, acetoacetic ester, acetyl acetate, ascorbic acid, benzoin). Thus, with the introduction of dimethylaniline in an amount of 0.03 ... 0.05%, the gelatinization time is reduced by 3...4 times.
A solution of polyester resin in a monomer is characterized by low stability due to the interaction of components. To increase stability, reaction retarders - inhibitors (for example, hydroquinone) are introduced into its composition in an amount of 0.02 ... 0.03% by weight of the total varnish.
Depending on the conditions under which curing of paint and varnish coatings can occur, polyester varnishes are divided into cold-curing varnishes and varnishes that are cured under the influence of various types of radiation (IR rays, UV rays and a stream of accelerated electrons).
Coatings such as polyester varnishes are often used in the furniture and industrial industries. The product range includes gloss and matt finishes suitable for coating metal and wood substrates. In addition to paint and varnish materials, polyester primers, which are indispensable for closed-pore finishing, are actively sold on the market.
Properties of polyester-based paints and varnishes
This type of product is characterized by increased performance characteristics. A product coated with this varnish looks brighter in appearance, and the surface acquires a shine similar to wet effect. When using pigmented varnish, the surface acquires distinctive decorative properties.
In terms of their composition, polyester compounds are either paraffin-containing or paraffin-free, each of which is distinguished by its specific operating details.
A distinctive feature of polyester varnishes lies in their properties, namely:
- fits well on a wooden base;
- cope with minor imperfections: mechanical defects, chips or dents, grooves resulting from grinding;
- forming an even and smooth glossy coating, which, if necessary, is sanded after drying to remove the top paraffin layer.
Features and advantages of using polyester paints and varnishes
Among the distinctive characteristics of the polyester composition for wood:
Features of paraffin-containing compositions
Polyester varnishes for wood, the component composition of which includes unsaturated resins dissolved in styrene. In addition, it contains catalysts (initiators) and accelerators (accelerators) of the polymerization process. Due to the paraffin content on the surface of the product, a thin film is formed that prevents the evaporation of styrene and the oxidation of the inner layers of varnish. This is what makes it possible to achieve a film-forming coating that is distinguished by its durability.
The methodology for applying paraffin-based wood varnish is pouring and spraying. The treated surface dries for at least 180 minutes at a temperature of +20 o C (±2 o C).
The percentage of dry residue of the paraffin-containing polyester composition is up to 94.95%. This is a property that allows minimizing the consumption of paints and varnishes for covering the surface of furniture on an industrial scale.
Features of non-waxed varnishes
The composition increases the adhesive properties of surfaces. The performance of such varnishes is lower, but the limits of the temperature range allow this material to be used more widely compared to waxed varnishes.
To apply to the surface of a wooden product, the pouring method or a special pneumatic spray in an electrostatic field of high voltage currents is used. When using the latter method, it is possible to significantly save on the consumption of polyester composition.
Main characteristics of polyester varnish for metal
Metal is a material characterized by strength and reliability, but like everything that surrounds us, sooner or later it loses its characteristics, becoming unsuitable for use. It is worth noting that the structures located on outdoors fall into disrepair faster than others.
With constant exposure of the metal surface to sunlight, precipitation, temperature changes and other climatic factors and environmental influences, rust forms on the metal surface, which indicates an irreversible reaction - corrosion.
To protect metal bases from such a fate, special varnishes and paints are used, including polyester metal varnish. This type of coating contributes to the formation of a special protective decorative layer on the surface of the product.
Several techniques are used to apply paints and varnishes to metal structures:
- using a brush;
- by means of a roller;
- when using a spray gun;
- through a can.
Of course, the last two options are preferable due to the fact that the varnish lays evenly and is consumed more slowly, evenly penetrating deep into the structure of the surface layer of the material and forming a reliable protective coating.
It is worth noting that among the properties of polyester varnish is strong water-repellent ability, which protects the surface of both metal and wood from corrosion and rotting, respectively.
Now you can imagine what a polyester composition is and why it is needed. The given features of certain varieties of polyester-based coatings will help you focus on choosing the required option, narrowing the range of product assortment depending on the need.
Katzenelenbogen 03/12/2015 - 16:27
Once upon a time, in ancient Soviet times, the highest level of practicality
And it was chic to cover the parquet with polyester varnish.
As I remember right now, it was poisonous and smelly, but resistant to wear
(according to the impressions of that time) was incredible.
Is this true today or is it just childhood memories?
Sopsno, I'm thinking... well, you've gone crazy.
Stas 03/12/2015 - 16:29
Yeah. And in a thick thick layer 😊 Take any modern water-based one, even lobadur, just glossy. Durability is beyond praise.
Katzenelenbogen 03/12/2015 - 16:35
Stas
Durability is beyond praise.
Almost all of these water-based varnishes can be pierced with a fingernail.
And that polyester one could be scratched with something sharp, but leaving a dented groove with a fingernail or a piece of wood is a waste.
azlk77 03/12/2015 - 16:39
Thing! He covered the parquet with it himself. When they moved into the apartment, they varnished the parquet floors and killed the bugs and cockroaches at the same time 😀 A colleague developed a burn to the respiratory tract and asthma when he covered the apartment under the closet and without a gas mask. There were two types: “Leningrad” and “Moscow”. The pros argued which one was more poisonous. But very wear-resistant. Now some modern ones are odorless.
Stas 03/12/2015 - 17:51
If you are fundamentally PE, then look for Sayerlack.
Stas 03/12/2015 - 21:58
:) Only if durability is most important to you, take the glossy one. Matte shit.
Katzenelenbogen 03/12/2015 - 23:13
Stas
😊 Only if durability is most important to you, take the glossy one. Matte shit.
And I will remember this.
😛
kaka 03/13/2015 - 12:25
At the dacha I use “Yachtny”, which has a giraffe. It may not be budgetary for the floors, but the street staircase to the porch hasn’t been noticed for five years now. Yes, inside the house too. Only I like it better matte, where the matteness in it is seen as a less bright shine and does not hit the eyes.
avkie 03/13/2015 - 06:58
I covered the floor at the dacha with 3 layers of semi-matte polyester varnish. really very durable.
Katzenelenbogen 03/13/2015 - 13:09
avkie
I covered the floor at the dacha with 3 layers of semi-matte polyester varnish. really very durable.
What is his last name?
Stas 03.13.2015 - 13:16
KatsenelenbogenPoly-R is his last name. True, this brand is bottled from Yaroslavl to Magadan, the quality varies greatly...
What is his last name?
carrier 03/13/2015 - 14:45
Polyurethane varnish is better, does not stink and is very wear-resistant. He hesitated to sand it down on the stairs. 😀
Katsenelenbogen 03/13/2015 - 15:28
kaka
At the dacha I use “Yachtny”, which has a giraffe.
Stas 03/13/2015 - 15:45
Katsenelenbogen
I looked through 1000 images of “yacht varnish” on Google, but couldn’t find a giraffe.
Katzenelenbogen 03/13/2015 - 16:22
Stas
Your Google is unlicensed. Second row, third from right
Some kind of small giraffe, inconspicuous, but the giraffe must be big.
😊
Understood.
Stas 03.13.2015 - 17:51
KatsenelenbogenWhat a varnish, such a giraffe 😊 By the way, they generally bottle Turkish yacht... R is probably from “horns and hoofs” 😊 😊 An office like the famous seller of other people’s spare parts in their own boxes, TRW 😊)
Some kind of little giraffe
paradox 03/13/2015 - 18:01
polyester is the hardest varnish.
Stas 03/14/2015 - 22:30
paradoxStiffness - that is, hardness? This is largely a drawback. We glued the boats out of fiberglass and PE varnish, so we had to add plasticizer 5-10 times more than normal so that the finished layer would not chip from impact.
polyester is the hardest varnish.
not only hard, but also fireproof.
production in Russia has been discontinued.
imports are much softer and more expensive.
Production in Russia - it's a pity...
Imports are different. Some should be thrown away altogether. I personally used the Sayerlack I mentioned and have no complaints. The price tag - yes, especially today, is inhumane... Well, for the estate of a maid...
Stas 03/15/2015 - 10:25
paradoxWell then of course 😊
looking for someone.
Katzenelenbogen 03/15/2015 - 14:12
paradox
and for pianos
Take it easy!
Such varnishes are strictly contraindicated for pianos.
Only polish, soft and fragile.
Although there are pianos made of chipboard covered with polyester, the culprit is.
😊
paradox 03/15/2015 - 15:56
Such varnishes are strictly contraindicated for pianos.
By the way, their pianos were even exported to Canada.
Stas 03/15/2015 - 18:35
paradoxYes, all pianos and grand pianos are coated with high-strength varnish. Mr. Katsenelenbogen simply did not go to music school and believes that Stradivari’s main secret is not to use polyester varnish 😊 😊 Although absolutely all musical instruments are varnished 😊 Even copper pipes are polished and varnished 😊
the Yakov Becker plant, which produced pianos in St. Petersburg,
Stas 03/15/2015 - 18:39
KatsenelenbogenEven in a nightmare, chipboard is not used. It’s never dawn on the most fucking pianos. All inexpensive tools are made from glued furniture board covered with veneer. The really bad ones were covered with black glossy NC paint and polished. 😊
Although there are pianos made of chipboard,
carrier 03/15/2015 - 20:06
Stas
and they polish and varnish
Stas 03/15/2015 - 21:44
carrierGoogle about the production of brass instruments and polished brass fittings for expensive suitcases. 😊 Varnish is used to cover many other things, such as hacksaws for wood, beer cans, bronze bathroom faucets and toothpaste tubes, if that’s what you need. About “different processes” - this is for a student who took the Unified State Exam, please.
Polished materials are not varnished. These are like completely different processes.
Katzenelenbogen 03/15/2015 - 21:46
Stas
Yes, all pianos and grand pianos are coated with high-strength varnish.
Stas
Even in a nightmare, chipboard is not used.
Stas
Mr. Katsenelenbogen simply did not go to music school and believes that Stradivari’s main secret is not to use polyester varnish
Well, that was not the case.
😊
However, I am a little in the subject, well, just a little, but enough to laugh at the “experts”.
1.
I don’t know what they cover instruments with now, but they have ALWAYS been coated with varnish, which is a type of varnish.
Many layers, manual stretching, special techniques - now this is lost, as you might guess.
2.
About chipboard.
😀
paradox
The Jacob Becker plant, which produced pianos in St. Petersburg, used domestic varnish from the Tantalum plant.
In fact, I learned to work with this varnish at Becker..
The YaB plant produces furniture that has all the external features of pianos and grand pianos.
As for Canada, this firewood was happily accepted there due to its relative cheapness.
The old "Red October" sometimes produced real instruments.
After Stalin's death 😛 everything went the usual way, that is, to hell.
Although the brand still stood for 10-15 years, even tall instruments came across.
Stas 03/15/2015 - 23:13
KatsenelenbogenRave. Chipboard muffles the sound nah. It's the same as a drum made of felt or a frying pan made of basalt wool. Can I proof the chipboard in the piano?
I personally observed instruments built from furniture board - chipboard and veneer on both sides.
Stas 03/15/2015 - 23:18
KatsenelenbogenI couldn’t be so brutal, and under the threat of sanctions from my mother (deprivation of the modeling club, deprivation of DOSAAF, etc.) I was forced to graduate from music school 😊 😊
Well, what can I say... or rather, advise...To begin with, I’ll say that my heroic dad was a piano maker at the Accord factory,
and taught me this skill since childhood, wanted me to follow in his footsteps.
No such luck
paradox 03/15/2015 - 23:19
Polished materials are not varnished.How come they don’t cover it??
The YaB plant produces furniture that has all the external features of pianos and grand pianos.I won’t argue - I don’t understand pianos, unlike wood and varnishes.
but after the closure of tantalum, Becker also had problems with cheapness.
I thought they were closed altogether
then this firewood was happily accepted there because of its relative cheapness.Apparently, they all sounded like that, otherwise they wouldn’t have bought firewood at all and for nothing.
in any case, the woodwork on the Yakov Becker was magnificent, and I don’t need strings
paradox 03/15/2015 - 23:21
The old "Red October" sometimes produced real instruments.there was also polyester there.
Stas 03/15/2015 - 23:21
paradoxI’m telling you, the Unified State Exam 😊 The death of education, and I’m too lazy to even use Google 😊 😊
How come they don’t cover it??
carrier 03/15/2015 - 23:41
paradox
How come they don’t cover it??
StasSomeone else's generation.))) Polishing is grinding using polish or oils, no varnish is used.
I’m telling you, the Unified State Exam is the death of education, and I’m too lazy to even use Google
paradox 03/15/2015 - 23:52
Polishing is grinding using polish or oils, no varnish is used.Ouch!
polish or oil is impregnation, not polishing.
carrier 03/16/2015 - 12:09
paradoxAfter the finish line is not necessary. It all depends on your goals. Varnishing is just painting.
If any wooden product is varnished, then it MUST be polished.
paradoxOil is used as impregnation.
yes, they polish not with oil, but with abrasive, that is, polishing paste
paradox 03/16/2015 - 12:44
Oil is used as impregnation.exactly.
not polishing.
After the finish line is not necessary.to whom the mare is the bride.
(With)
I mean, you don’t have to polish it.
carrier 03/16/2015 - 01:27
paradoxNot all varnishes are glossy, and the requirements for the surface are different; for some, on the contrary, brushing is needed.
but it’s better not to show such a product to anyone.
carrier 03/16/2015 - 01:30
paradoxThe process of applying the compositions includes polishing, the pores of the wood are partially or completely closed, the surface becomes shiny, this is a rather long and labor-intensive procedure, several hundred layers of oil or polish can be applied.
not polishing
paradox 03/16/2015 - 01:36
Not all varnishes are glossy,Not all.
but it can also be polished after matte.
but you wrote something else altogether -
Polished material is not varnishedthat is, polished is equal to unvarnished.
which is nonsense.
The process of applying compounds includes polishingcompletely optional
Katzenelenbogen 03/16/2015 - 01:43
Stas
Chipboard muffles the sound nah.I remember that this is a polyurethane varnish, semi-matte (because I don’t like gloss)
it was some kind of inexpensive varnish, made by us.
I took it in a 3.5 kg container, to the dacha (6.5x6.5) on the floor and veranda - it took 3 cans, painted it in 3 layers, dried it for a week, then two more layers.It got stained in one place, so then I had to remove it by sanding - it was very difficult to sand it.
therefore, I think it will not be erased soon.avkie 03/16/2015 - 11:11
carrier
Polyurethane varnish is better, does not stink and is very wear-resistant. He hesitated to sand it down on the stairs. 😀and dries quickly
Covering 3 layers in a day is no problem. morning, afternoon and evening. I arrived a week later and covered it with a couple more layers.avkie 03/16/2015 - 11:16
paradoxyes, after impregnation the wood is also polished
if we don’t want a hedgehog on the surface.that's right. because if you wet dry wood or plywood with water, then all the fibers on the surface will immediately stand upright.
This is how they polished it before, wet it, dried it and removed the hedgehog.
if you varnish it will be the same.
so after the first layer I dried it well and removed the hedgehog with a sander.I didn't film the hedgehog except on the steps of the stairs. because because of this effect, the steps turned out to be very successful, non-slip! I left it like that. not slippery even in socks.
Stas 03/16/2015 - 20:19
KatsenelenbogenI even saw an iron violin. 😊 Iron resonates normally. And chipboard/fibreboard is evil in music. instrument...
Ha!
Have you seen a tin guitar?© 2020 This resource is a cloud storage of useful data and is organized with donations from users of the site forum.guns.ru who are interested in the safety of their information
Spreading polyester varnishes explained by the fact that the resulting finishing coatings have a number of positive characteristics: 1) due to the high dry residue, almost all of the components included in the varnish remain in the coating; 2) since the shrinkage of the varnish film during curing is insignificant, polished surfaces retain their gloss for a long time, coatings can be sanded and polished well; 3) coatings have high physical and mechanical properties (hardness, heat resistance, resistance to water, alcohols, alkalis, acids).
In woodworking, the most common are paraffin-containing polyester maleate varnishes. They consist of a base, an initiator and an accelerator. The varnish base is a solution of unsaturated polyester resin in styrene. An initiator is introduced to harden the varnish, and an accelerator (as can be understood from the term itself) is added to speed up curing. The reader obviously understands that these additives are introduced immediately before using the varnish (most often they are mixed already on the surface to be finished, otherwise the varnish will polymerize and will be unsuitable for use).
The role of paraffin in polyester varnish is special. The chemistry of polyester varnish is such that when a reaction occurs after its application under the influence of atmospheric oxygen, a thin sticky layer of resin remains on the surface. The introduction of paraffin that floats to the surface insulates the liquid film from atmospheric oxygen. After the coating has cured, the paraffin film and the top layer of varnish are removed by sanding.
Polyester varnish coatings are dried at room temperature. Complete curing occurs after 8-24 hours (depending on the brand of varnish). This is one of the main disadvantages of polyester varnish.
Wax-free polyester varnishes are also available. Here, the solvent instead of styrene is polyester acrylate. Drying the coating of this varnish can be cold or hot.
The reader will be interested to know that paraffin-containing varnishes can only be applied to horizontal surfaces, while paraffin-free varnishes can also be applied to vertical surfaces. But paraffin-free varnishes have a lower dry residue (60-70% instead of 95%), and in this case they require heating for 2-3 hours to cure.
In recent years, they have become increasingly widespread polyurethane varnishes, since polyurethane coatings have a number of valuable properties: high adhesion to the substrate, good filling of wood pores, high film hardness and high elasticity, abrasion resistance, water, heat and weather resistance, etc. Curing of polyurethane paint and varnish coatings occurs under exposure to chemical reagents introduced during the application of varnish.
Some other types of paints and varnishes are also used in woodworking. These include enamels based on alkyd resins- glypthal and pentaphthalic. Their drying time at 18-20° C is up to 48 hours, but the coatings have high weather resistance, so they are used for finishing windows, car parts, agricultural machinery, etc., i.e., products used outdoors.
When finishing in woodworking, materials based on melamine-formaldehyde resins, already familiar to the reader, are also used. These are primarily primers and putties. But these resins are of greatest importance in the manufacture of paper-based finishing films (colloquially called synthetic veneer). Due to the increasing shortage of valuable types of wood with a beautiful texture, these finishing films are increasingly used for cladding furniture panels. But in film production technology, despite its apparent simplicity, there are significant difficulties.
The coloring of the paper and the texture printed on it must be light and heat resistant, and also resistant to varnish or impregnation with resins. The paper is impregnated with liquid urea-melamine-formaldehyde resins on continuous machines, i.e. the paper must have sufficient wet strength. If paper film is pressed onto wood board (or plywood) to create a finished finish, all components of the film must have increased heat resistance. In addition to this method, others are used: pressing paper film and subsequent finishing, pressing paper film with a finished surface that does not require further finishing. All three schemes have recently been increasingly used. Each of them has a specific area of application, but all schemes are based on paper impregnated with urea-melamine-formaldehyde resin.
On the Russian market, polyester varnishes of Russian or foreign production can be purchased from the companies Technocolor, Lac-Premier, LIGA, TimberAL, BaltPromKomplekt, Industrial Paints, Trading House EuroChem-1, I.T.I.", "ART-Industry", "Phaeton", Tanzor-M, "TENDENT", "LKM ServicePlus", "Somek", "Trade and industrial company "INFRAHIM"", "Production association ""Paints for Everyone"", "Fibrolite", "CHELAK", FKP "Kamensky Plant", "VitaKhim". The advantages of polyester varnishes: large dry residue, excellent filling ability, high hardness and physical and chemical resistance. When dry, such varnishes form a hard film of great thickness, resistant to various reagents and water. Polyester varnishes are usually applied to the surface of products by pneumatic spraying or pouring (using a varnish-filling machine).
Polyester varnishes are divided into paraffin-containing and non-paraffin (hot or cold curing). Paraffin-containing varnishes are characterized by a high content of film-forming agents (93-97?%), which determines their high efficiency. Such varnishes are used to obtain coatings with a mirror shine or matte coatings for the front and facade surfaces of expensive furniture. Paraffin-containing varnishes can be applied in thick layers, since their shrinkage is small, and curing occurs faster and more reliably in thick layers than in thin layers, so a coating with a thickness of 300-400 microns can be obtained in one or two applications. Priming and filling the substrate are rarely used when finishing with paraffin-containing varnishes.
The main disadvantage of varnishes containing paraffin is their low adhesion to wood. These varnishes are characterized by low viscosity and high fluidity. Solutions of these varnishes have a short pot life (about 30 minutes). Due to their high fluidity, paraffin-containing varnishes are used mainly for finishing horizontal panel surfaces. When applied to vertical surfaces, special additives are introduced into them.
If, when preparing the wood surface for finishing, painting with aqueous solutions of dyes is not intended, it is permissible to treat rough surfaces with such varnishes, since the varnish does not cause noticeable swelling of the surface layer of wood. For the same reason, the operation of removing wood lint can be excluded from the technological process. paint coating material product
Paraffin-free varnishes contain about 70?% film formers. The pot life of working solutions of these varnishes is at least 20 hours. Coatings based on paraffin-free varnishes, in contrast to coatings based on paraffin-containing varnishes, are characterized by higher elasticity and adhesion to various substrates. Wax-free polyester varnishes are easy to use. They are often used in a combination of “polyester primer plus polyurethane varnish or enamel.”
Domestic manufacturers of paints and varnishes produce many brands of polyester varnishes. For example, varnishes of the PE-246, PE-265, PE-2136 brands are suitable for forming high-gloss coatings on panel furniture parts lined with natural, synthetic veneer or materials based on impregnated papers. They also produce PE-2136U ultraviolet-curing varnish, which ensures the formation of high-gloss coatings on panel furniture parts lined with natural, synthetic veneer or materials based on impregnated papers. Varnish PE-2311 is intended for obtaining matte coatings with a finished effect on panel furniture parts lined with natural veneer or materials based on impregnated papers, and varnish PE-2315 is intended for obtaining glossy coatings of a similar effect. For finishing wood products used indoors, followed by polishing, as well as for painting musical instruments, high-gloss varnish of the PE-232 brand is in demand. Varnish PE-251 is intended for obtaining transparent glossy coatings. It is used primarily for high-quality finishing of chairs, armchairs and other solid wood products. Manufacturers produce grades PE-251A and PE-251 B.
