Polymeric coverings of a metal tile. Polyester powder paints Which coating is better

Let's take a closer look at the most important characteristic profiled roof - coating of metal tiles, responsible for the safety of its appearance and protection of metal from corrosion and impact natural factors. Variety of protective polymers used in thin sheet metal roofing(profiling including), is reduced to the main five. We will consider them in this article and try to find out which roofing iron coating is better.

For starters, let's comparative characteristics all types polymer coatings:

Polyester (PE) coated metal tile

Due to its low cost, metal tiles with this type of coating have become the most common. Polyester (PE) or polyester is a glossy coating with an average thickness of 25 microns. The downside can be considered low resistance to mechanical stress, and therefore products called "polyester" require careful transportation and accuracy during installation. Due to its characteristics and low cost, PE metal tiles have proven themselves well in middle lane Russia and CIS countries.

Matte polyester (Matt PE, Purex)

Another kind of protective polymer "polyester" with the addition of Teflon, due to which the metal tile is given a noble matte shade and a slightly rough surface. Another advantage of this coverage is additional protection from impact ultraviolet rays which improves the color fastness of the roofing material. As a rule, the thickness of Matt PE is 35µm. The most famous representatives of matte polyester are Viking (Metal Profile) and Velur ( grand line).

PVDF

Usually used for facade decoration and less often used for roofing materials. PVDF - very resistant glossy finish both to loss of color and to mechanical damage. In this variant, high-quality steel with the first class of zinc content (275 g/m2) is usually used. PVDF is 80% polyvinyl fluoride and 20% acrylic. It is also produced by the Finnish metallurgical concern Ruukki in a matt finish (matt PVDF).

Polyurethane coating (Pural)

The highest quality and resistant in its properties protective polymer for metal tiles 50 microns thick. Better known as "pural" (abbreviated as PU) due to the ancestor this product- Finnish plant Ruukki. Polyurethane type of coating is resistant to fading, impact environment and temperature difference. At present, the pural is issued by the majority metallurgical plants for the production of roofing metal materials. For example, Colorcoat (English development - Prisma, supplier - Metal Profile), Arcelor (Belgian coating Granite HDX, supplier - Grand Line), Finnish manufacturer Pelti ja Rauta (Prelaq Nova coating, supplier - Mir Roof).

Important: the polyurethane coating, with the maximum visual similarity to polyester, has a small rough surface, reminiscent of powder coating!

Like polyester, this type of protective layer of metal tiles has a matte finish, which allows you to achieve the maximum similarity of the profiled steel material with ceramic roof.

Plastisol (PVC)

The thickest, and therefore the most resistant to mechanical action upper layer roofs. Thickness - 200 microns. Abbreviated PVC, some manufacturers can be found under the brand name Solano or HPS200. The composition of the polymer includes plasticizers and polyvinyl chloride. The texture of the metal tile has a characteristic pattern resembling "skin".

With all its apparent advantages, "plastisol" is extremely unstable to temperature changes and exposure to ultraviolet rays. Therefore, it is not recommended to use metal tiles with this type of polymer in southern regions. Typically used in industrial and manufacturing facilities.

These are the main types protective coatings. Other names and variations are modifications of the above polymers.

For example, at the heart of the Belgian metal tile cloudy, imitating natural roofing, lies modified polyester. This creates a unique pattern, reminiscent of the firing of ceramics.

Similar to Cloudy, steel ECOSTEEL, which has the maximum resemblance to stone or wood, is also the result of polyester modification. Basically, this type of polymer is used in the manufacture of materials for the fence (profiled) or facade ( metal siding).

Which coverage is best?

Based on the properties and characteristics of the protective polymers of metal tiles, the most reliable coatings can be distinguished. Polyurethane has both sufficient thickness and excellent UV resistance. Such a metal tile will serve for a long period of time in almost any region, and is rightfully considered the best. For central or northern regions plastisol is ideal. Due to the polymer thickness of 200 microns, the coating will withstand increased snow loads or ice. Other types of colored roofing layer are inferior to polyurethane and plastisol in their characteristics. It is not recommended to use a metal tile with a covering "polyester" in regions with an aggressive climate.

Manufacturers are constantly improving protective polymers for sheet products, offering new solutions that extend the service life of metal tiles, corrugated board and other steel products. We hope that the article was useful in choosing better coverage roof iron.

Corrosion reduces strength and degrades appearance metal structures leading to their complete destruction over time. Polyester paints perfectly protect the metal from rust, while giving it an aesthetic appearance.

General characteristics

Solid dispersed structures, in the combination of which there are film-forming resins, hardeners (desiccants), various pigments, as well as setting additives, are called powder paints.

Such compositions are inherent:

• homogeneity (composition uniformity);
• physical and chemical constancy;
• stability of the mixture during operation and storage.

Polyester powder paints are produced as follows: all components are mixed, then homogenized, (this takes place at high temperature in a twin screw extruder). The finished melt is cooled, crushed and sieved, thereby achieving the uniformity of the powder. These paints are used exclusively for metal surfaces. However, over the past decade, several types of powder coatings for plastic and wood have been created.

Such paints are environmentally friendly, good protective properties, decorative. In addition, they are economical. Coloring takes place in a special chamber, which achieves 100% use of the material.

Features of powder paint:

• decorative (the ability to use the widest color palette);
• reliability (high chemical stability);
• the ability to get a fairly thick coating in one coloring;
• complete absence of streaks on the verticals;
• good adhesion.

Varieties

Powder paints based on thermosetting film-forming agents have found wide application. They are divided into 2 types: polyester and epoxy-polyester.

They are based on a special fine powder, which uses polyester, pigments and additives, but does not contain any solvents and epoxy resin.

Polyester paints are characterized by low toxicity, so they are used even for painting bicycles and car parts. They are designed for various metal surfaces regularly exposed to various weather conditions (high/low temperatures, snow, rain, hail, wind). Resistance to temperature extremes is very high. Application methods - electrostatic or tribostatic methods.

Other positive features include:

• excellent filling and hiding power;
• resistance to aggressive chemicals;
• drying speed.

Advice! Store coatings for no more than 12 months at a temperature of 25°C.

Epoxy-polyester

Such paints are based on polyester (up to 50 - 70% of the total composition) and epoxy resins, supplemented with a hardener, fillers and pigments (up to 35 - 50% of the total composition). They belong to powder enamels internal use and have high strength characteristics:

• impact resistance;
• elasticity;
• solvent resistance;
• good spreadability.

Epoxy-polyester (hybrid) paints are used to color and improve the appearance of metal products used indoors. It could be:

• electrical equipment;
• Appliances;
• dishes;
• Furniture for home and office;
• car accessories;
• heating devices;
• travel accessories.

Staining methods: electrostatic or tribostatic. Epoxy-polyester compounds provide excellent protection against corrosion, do not turn yellow when exposed to high temperatures.

Advice! When working with such enamels, be careful - wear protective mask, special goggles and gloves.

Painting methods

There are 2 ways to apply powdered polyester and epoxy-polyester compositions - these are electrostatic and tribostatic spraying. Sample process painting consists of the following steps:

1. Preparation of the base of the object for painting - treatment with primers.
2. Applying powder to the object to be painted is one of the most suitable methods for this.
3. Polymerization at a temperature of 140 - 220 °C. It depends on the type of paint. During the heating process, the powder slowly melts, resulting in a durable, uniform coating.

Powder paint manufacturers produce compositions that resemble chrome, patina, copper, anodized aluminum and some metals. Surfaces after painting can be glossy, able to hide minor defects, or textured, emphasizing dignity. The choice for a potential consumer is huge.

Usage: to obtain protective and decorative coatings on various products, for example, on ceramic tiles, glass. Essence: a polyester coating is obtained by applying a composition to the surface of the product, including an unsaturated polyester resin based on polyalkylene glycol maleinate phthalate (91-97 wt.%) and a mixture of photoinitiators: hexachloro-p-xylene (2.0-6.0 wt.%), - hydroxyacetophenone (0.5-1.5) and 2,4,6-toxide (0.5-1.5 wt.%). The applied composition is cured using UV irradiation and a coating is obtained, characterized by increased adhesion, elasticity, chemical resistance, including boiling. 1 tab.

The invention relates to a technology for producing protective and decorative polymeric coatings on various products, such as ceramic tiles, glass. It is known that the surface of ceramic, glass, metal products to strengthen and give certain decorative properties coated with polymer coatings, for which polymerizable compounds are used, for example, unsaturated polyesters. To accelerate the curing of polyester coatings, various chemical compounds. These compounds include various peroxide compounds, such as benzoyl peroxide /1/. The main disadvantage of using peroxide compounds for these purposes is their explosiveness. A variety of polymerization initiators also includes photoinitiators used in the UV or IR curing of polyester coatings. A large group of polymerization photoinitiators is known. These are halohydrocarbons, for example, trichlorotoluene, hexachloro-p-xylene, hexachloro-m-xylene /2/, polychlorinated triphenyl /3/, derivatives of benzoin, benzophenone, acetophenone, for example, dimethoxy-2-phenylacetophenone /3/, organoelement compounds, including including organophosphorus compounds, such as triphenylphosphine /3/. However, single polymerization accelerators do not provide high speed curing of polyester coatings, and also do not provide the formation of coatings with sufficient resistance to abrasion, good elasticity, which is known from previously published works /3/. Closest to the method chosen as a prototype is the known method of UV curing of a polyester coating, which uses a mixture of polymerization photoinitiators containing an acetophenone derivative, for example dimethoxy-2-phenylacetophenone, then a halogenated aromatic hydrocarbon compound, for example polychlorinated triphenyl, and also an organophosphorus compound, for example trimethylphosphine, taken in a weight ratio of 1-30:30:1-30/3/. The coatings obtained by this method are characterized by high elasticity, chemical resistance, however, as additional studies have shown, they cannot withstand boiling in water. New way obtaining a polyester coating on products includes applying a composition containing a mixture of polymerization photoinitiators, including hydroxyacetophenone, hexachloro-p-xylene, 2, 4, 6-toxide at their mass ratio equal to wt. unsaturated polyester 91-97, hexachloro-p-xylene 2.0-6.0, hydroxyacetophenone 0.5-1.5, 2, 4, 6-toxide 0.5-1.5, and further UV curing of the coating The method differs from the prototype method with a new qualitative and quantitative composition of photoinitiators. Coatings obtained after UV - curing of unsaturated polyesters containing the Specified mixture of photoinitiators are characterized by high strength when testing the sample for boiling, they have high adhesive strength. Resins based on glycols, phthalic maleic acids are used as curable unsaturated polyesters. The amount of polyester in the mixture is 91-97 wt. Reducing the amount of polyester below the claimed leads to incomplete polymerization throughout the depth of the coating, and an increase in the amount of polyester leads to a slowdown in the polymerization process, which leads to the formation of a sticky coating. The polymerization of the unsaturated polyester coating is initiated by the presence of a mixture of photoinitiators of a certain composition. When understating the amount of each photoinitiator below the claimed: hexachloro-p-xylene below 2 wt. and hydroxyacetophenone and 2, 4, 6-toxide below 0.5 wt. there is a sharp decrease in the polymerization rate, which requires repeated irradiation of the surface using high power UV irradiation. If the amount of hexachloro-p-xylene exceeds 6 wt. hydroxyacetophenone above 1.5 wt. and 2, 4, 6-trimethylbenzoylphosphine oxide above 1.5 wt. an uneven surface is observed. The curing process of the coating is carried out with the help of UV irradiation, which is 6-8 kW / h. The invention is illustrated by examples 1-5/cm. example 1 and table/. Example 1. Unsaturated polyester brand 609-21-M /91/, hexachloro-p-xylene /6g/, hydroxyacetophenone /1.5g, 2, 4, 6-toxide /1.5g/ are mixed in a glass container, heated on water bath to 70 o C, the finished composition is poured onto glass and the applicator rolls out a coating layer 100 microns thick, after which the coated glass plate is subjected to UV irradiation using a UV irradiation lamp with a power of 8 kW / h.

Claim

A method for producing a polyester coating by applying a composition to the surface of an article, including an unsaturated polyester resin based on polyalkylene glycol maleate phthalate and a mixture of photoinitiators, followed by UV curing, characterized in that a mixture of hexachloro-p-xylene, hydroxyacetophenone and 2.4 ,6-trimethylbenzoyl-diphenylphosphine oxide in the following mass ratio of the components of the composition, wt. Unsaturated polyester resin 91 97 Hexachloro-p-xylene 2.0 6.0 - hydroxyacetophenone 0.5 1.5 2,4,6-toxide 0.5 1.5o

Similar patents:

The invention relates to photography, in particular to a photopolymerizable composition (FPK) for the manufacture of a protective relief of a matrix of electroforming extension

The invention relates to the field of obtaining polymer compositions based on polymer resins, in particular, unsaturated polyester, which can be used as protective coatings in the repair and installation of underwater oil pipelines, to protect against corrosion and abrasive wear of desulfurization units at industrial thermal power plants, as well as to protect equipment , pipelines operating at low temperatures

The invention relates to finishing paintwork materials, in particular to putties for sealing various irregularities and correcting defects in metal and wooden surfaces in structures operated in atmospheric conditions and indoors, for car repair

The invention relates to the field of chemistry and technology of polymers, namely, self-curing polymer-mineral compositions, which are used primarily for leveling car bodies, as well as for leveling other metal and non-metal surfaces that are not in contact with food

The invention relates to the field of obtaining film-forming compositions based on unsaturated oligoesters, cured by UV radiation or high-energy radiation and forming glossy protective and decorative coatings on wood, cardboard, cement and other materials

Polyester coatings

Polyester coatings differ from all others in transparency, hardness and mirror shine. These properties, although to a lesser extent, are also inherent in polyurethane coatings. You cannot repair them at home. In order to find out what kind of varnish to cover the furniture, it is recommended to make a test. To do this, a drop of 10% sodium hydroxide solution should be applied with a pipette to an inconspicuous area of ​​​​the surface. If the furniture is covered with alcohol varnish, the coating will dissolve in 2-3 minutes. In the event that the film has not dissolved, a drop of solvent for nitro-lacquers (acetone, solvents 646, 647, etc.) should be applied to the same place. If the film does not dissolve, then the coating is alkyd, polyester or polyurethane.

When the coating is dull, the gloss can be restored with the help of various polishing products available in retail trade.

If the entire lacquer coating is damaged, it should be removed and a new one applied. The old varnish film is removed tone

with sandpaper or with solvents. Remove varnish film from damaged area be very careful not to simultaneously remove pore-filling compounds and dyes from the surface of the wood. If, after removing the old varnish film, the primer, wood filling and its paint layer are not violated, you can proceed to restore the varnish.

For the restoration of nitrocellulose coatings, it is best to use furniture nitro-varnishes in aerosol packaging. In this case, areas that do not need to be varnished are protected with paper or a layer of petroleum jelly.

Nitrolac is applied in 3-4 layers. Oil varnish can be applied with a swab in 2-3 layers, allowing each layer of varnish to dry before applying the next. When repairing an alkyd coating, PF283 varnish is most often used. Newly applied lacquer needs to be polished.

kitchen furniture and other household items that have an opaque finish can be repainted. Before painting, the old coating should be degreased: it is enough to wipe it with white spirit (if the coating is oil or alkyd) or thinner 646 (if the coating is nitrocellulose). On the old coating is usually painted with a brush in 2 layers. At the same time, for painting on oil and alkyd coatings oil paints and enamels are usually used (PF223, PF115, etc.), and for nitrocellulose coatings - NTs25 and NTs132 enamels.

Polyester powder paints are commonly used in scale industrial productions and used for coloring metal parts or structures. At home, painting with these compounds is almost impossible, since this requires special, rather complex, equipment. You can’t get by with the usual paint brushes or a roller.

Polyester powder paint - what is it?

The material is a solid dispersion, which includes:

• film-forming substances
• desiccants (hardeners that speed up the drying process),
• pigments (substances responsible for color formation),
• various additives that provide the paint with high technical characteristics.

Polyester powder paints do not contain any solvents, and there is no epoxy resin. These colorants belong to the group of thermoset film-forming coatings.

In their production, all components are mixed under the influence of high temperatures, the resulting mass is cooled and crushed, after which it is sieved. Due to this, the powder becomes homogeneous at the exit. The dispersion is distinguished by homogeneity, physicochemical stability, stability during storage and during operation.

Properties

In the description of the material, you can usually read that this coating is intended for metal; however, modern production produces polyester-based powder formulations that interact well with wood, plastic and other surfaces. Positive traits:

1. Profitability. Coloring occurs practically without loss of material.
2. Wealth color palette and, as a result, the decorative effect of the resulting coating.
3. Strong adhesion (the paint has a reliable adhesion to the base).
4. High resistance to aggressive chemicals.
5. Good hiding power and the possibility of obtaining a sufficiently dense coating as a result of one staining.
6. Absence of irregularities and streaks even on vertical surfaces.
7. Short drying time.
8. High anticorrosive properties.
9. Resistance to sudden changes in temperature and any atmospheric phenomena: hail, snow, rain (including acid).
10. Lack of reaction of the coating to ultraviolet (colour stability).

Polyester paints are used in the automotive industry, in the production of sports equipment, for painting parts of bicycles, power tools, gardening and household appliances. First of all, these coatings are designed to protect surfaces from aggressive external influences.

Practice shows that they perfectly cope with the task. Still, there are also disadvantages: the composition contains toxic components; It is very difficult to apply such paint on your own.

Coloring process

The preparatory stage consists in cleaning the surfaces from rust, if any, degreasing, applying primers and drying. Next, polyester paint is applied to the part by powder spraying. The final stage– thermal impact (from 140 to 220 °C), during which the coating melts and polymerizes. On the surface, a strong elastic protective film.

When painting by hand, the powder is applied using a spray gun, after which the part is placed in a chamber where heat treatment takes place. When the process is fully automated, all stages are carried out directly in the chamber, on the walls of which nozzles are located, through which the composition enters the surface to be painted.

After polymerization of the coating, the product is dried; after the required time has elapsed, the finished part is removed.

Coating Removal

When carrying out restoration work, it often becomes necessary to remove polyester powder paint from the surface. For this, they are used sandblasting machines, abrasive particles under high pressure are sent to the old coating, thus achieving an effect similar to the processing of the part with sandpaper. The cleaned surface is freed from dust, degreased, primed again and re-painted.

Advantages and opportunities

It is worth noting some properties of this unusual material which make it particularly attractive to the consumer.

Chemical resistance

Coatings obtained in use polyester paints, have increased resistance to the following substances:

• solutions of acids: sulfuric, hydrochloric, nitric, acetic, citric, phosphoric and others,
• ethyl and methyl alcohol,
• mineral oils,
• methyl ethyl ketone,
• compounds containing carboxyl,
• acetone.

Thanks to the processing with polyester coloring agents, the service life of parts of various designs is significantly increased.

decorative

Polyester paints are widely used in decorative trim. In addition to a variety of colors and shades, you can get additional interesting visual effects.

Moire

The dried surface resembles a texture sandpaper. Such a coating is universal, since it allows not only to mask minor defects on the base to be painted, but also to give the product an aesthetic appearance.

Shagreen

The covering is similar to the skin of a special dressing (hence the name); as well as the "moiré" effect hides flaws on the surface and gives it special elegance. This finish is often found on metal entrance doors or office furniture.

hammer effect

The surface looks very decorative and is associated with ancient iron, which was manually worked with a hammer. Original, beautiful and practical.

Metallica

The coating imitates gold, silver or chrome; can be glossy or matte. Often used for painting car parts, furniture fittings, plumbing, household appliances, and others decorative elements interior.