RU2398808C2 - Composition for making electroconductive protective-decorative coating of dielectric material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: composition contains a mixture of epoxy resins type E-40 and E-05 in weight ratio (90-86):(10-14) or Epikot 223 and Epikot 401 in weight ratio (87-83):(13-17), a mixture of organic solvents, mainly in form of a mixture of toluene, butanol and butylacetate or xylene, isopropyl alcohol and ethylacetate mainly in weight ratio 22:40-38, a hardener of mainly polyamide type, and fine metal powder, mainly aluminium, in the following ratio in pts. wt: mixture of high-molecular epoxy resins 100-120, mixture of organic solvents 64-78, hardener 21-26 and fine metal powder 28-37.

EFFECT: composition provides good protective properties, good aesthetic characteristics of surfaces, high bending and torsion strength of the material and resistance to surface mechanical effects, possibility of quality painting and repainting surfaces.

5 cl, 5 tbl, 6 ex

Description

FIELD OF TECHNOLOGY

The invention relates to the production of compositions for the manufacture of electrically conductive protective and decorative coatings of dielectric materials that can be used in various industries, in particular for the production of composite materials and articles with electrically conductive protective and decorative coatings and a dielectric base such as wood-fiber, suitable for powder coating plates (MDF) such as MDF, OSB, plywood, hardboard, particle boards (wood chipboard), wood, ceramics, brick, asbestos cement, ETOH et al.

BACKGROUND

Known composition used as glue or in the manufacture of castings, comprising a liquid epoxy resin, a hardener and a filler - coal, graphite, silica, silica flour, etc. [one].

The known composition of the epoxy putty for sealing deep ulcers of cast-iron castings composition, parts by weight, ED-16-100, hexamethylenediamine 20, powder, cast iron or iron 400 [2].

Known protective composition for protecting metal surfaces during cyclic changes in temperature in an alkaline environment and reducing permeability, including epoxy Dianova resin, amine hardener and cast iron powder, as an epoxy Dianova resin contains epoxy Dianova resin containing 18-23% of the epoxy groups ED-20, in as an amine hardener, polyethylene polyamine, and as a cast iron powder, high alloyed with nickel and copper, cast iron powder of a fraction of 20-63 microns, heat-treated in argon at a temperature ur 250-300 ° C for 40-45 min with the following ratio of components, parts by weight: epoxy resin 100-120, polyethylene polyamine 15-18, cast iron powder 400-500 [3].

These coating compositions usually require subsequent painting with traditional liquid paints or more economical and environmentally friendly and increasingly widely used powder paints.

Powder coatings are usually applied electrostatically to electrically conductive metal substrates. The deposition of powder coating on electrically conductive materials is provided by electrostatic forces. The powder is charged under the action of friction (triboelectric charge) or corona discharge. Then the charged powder is sprayed onto a grounded base.

The electrostatic charge on the particles of the powder coating allows you to apply a uniform powder layer to the substrate, and also causes temporary adhesion of the powder to the surface of the substrate. The strength of this adhesion is sufficient to transport coated products from the area where the powder was applied to the curing oven, in which the powder melts and forms a continuous film on the basis.

For the successful application of powder coatings, the conductivity of the substrate is of fundamental importance.

The use of powder coatings for coating non-metallic substrates with dielectric properties has technological advantages, allows to obtain high-quality layers of paint and reduces paint loss. However, it is much more difficult to apply a powder coating to non-conductive substrates than to metallic substrates, since the surface conductivity of most non-metallic materials, such as wood composite materials (based on OSB, plywood, hardboard, fiberboard, chipboard) is insufficient for effective grounding of the substrate. Therefore, the deposition of paint powder on these dielectric substrates does not help electrostatic attraction, and this leads to uneven deposition of the powder and poor adhesion of the powder to the substrate before curing the applied powder coating of the paint. The quality of the powder coating is unsatisfactory both on the front surfaces and on the edges of the materials to be painted.

A known method of increasing the electrical conductivity of the surface of dielectric fiberboard MDF radiation of ultra-high frequency (microwave heating) before applying a powder coating [19533858 DE-A]. Microwave heating causes a temporary increase in moisture content on the surface of the MDF, which reduces surface resistivity. However, microwave heating of large objects, such as MDF fiberboard, is uneconomical, and, in addition, uniform microwave heating of large objects is difficult to practically implement.

A known method of spraying on the surface of non-metallic bases of water before applying a powder coating to increase surface conductivity. The disadvantage of this is that during the melting / curing process, water vapor forms under the powder film, which leads to porosity, poor adhesion of the powder to the substrate and the formation of bubbles under the paint layer.

Known methods of pretreatment by exposing dry heat to a non-conductive base such as wood composite materials or natural wood, followed by applying the powder to a hot surface. For example, EP-A933140 describes the use of infrared radiation for preheating a stove. After that, a powder is applied to a plate having a certain surface temperature (for example, 55 ° C). The disadvantages of such methods are that due to heat loss, the edges of the plates often do not have sufficient paint coating.

To increase the electrical conductivity of the surface, a conductive, usually water-soluble soil is also applied to the dielectric base, which increases the surface conductivity and improves the quality of the subsequent application of powder paint. In particular, according to patent WO / 2006/129173, a water-alcohol solution of ammonium salt and sodium chloride, crude sea salt or sodium hyposulfite is used; according to US patents 20060084706, 20030180551, 7015280, an emulsion based on an emulsified solution of organofunctional silanes is used; according to GB 1524531 coatings based on a plasticized bioprotective composition for wood, water-repellent wax, polar liquid and solvents, according to US patent 7090897 introduce a conductive material based on cocoalkylamine with a solvent in lignocellulose ozy substrate, for example, MDF.

Known water-soluble primer TIGER Aqua-Lac 402/70001 14 (brochure company TIGER), which is applied to products made of dielectric MDF. After applying the primer, the sample is dried in two stages: horizontal, to avoid sagging, and vertical, using drying cabinets, in order to speed up the process of preparation for powder painting. Two-stage drying indicates a significant increase in the moisture content of the base surface.

Common disadvantages of the known water-soluble conductive soils are an undesirable increase in the moisture of the painted surface and, as a result, a decrease in the strength and shape-forming characteristics of most dielectric materials, especially fiberboard such as MDF, OSB, plywood, hardboard, chipboard.

A known method of applying powder coatings on a non-conductive base, in which the base is pre-treated with steam and heat at temperatures from 70 to 140 ° C for a period of time from 5 s to 10 min and then powder coating is applied by electrostatic spraying of a powder coating [4].

This pretreatment method allows powder coatings to be applied to non-conductive substrates with uniform deposition over the entire surface, including the edges, and without negative impact on the subsequent curing of the powder film, but it leads to an increase in the moisture of the surface layer and the formation of bubbles under the cured powder film after its thermopolymerization.

Known composition for coatings, including epoxy diane resin, dibutyl phthalate, melamine formaldehyde resin, titanium dioxide, polyethylene polyamine, a mixture of solvents of methylene chloride, ethyl cellulose and xylene at a mass ratio in the mixture from 35:25:40 to 45 20.35 at a ratio of components, parts by weight: epoxy diane resin 100, dibutyl phthalate 9.5-10.5, melamine formaldehyde resin 1.8-2.2, titanium dioxide 19-21, polyethylene polyamine 5.9-6.1, a mixture of methylene chloride, ethyl cellulose and xylene 120-138 [5 ].

The disadvantages of this composition are low electrical conductivity, insufficient water resistance and chemical resistance of coatings based on it.

Known composition for coatings, including epoxy Dianova resin, aminophenol hardener Agidol AF-2 based on a mixture of 2-ethylenediaminomethylphenol and 2,6-di- (ethylenediaminomethylphenol), flotation reagent-oxal based on ethers and formulas of dioxane alcohols, titanium dioxide in ethyl cellulose the following ratio of components, parts by weight: epoxy diane resin 100, aminophenol hardener Agidol AF-2 20-22, flotoreagent oxal 23-27, titanium dioxide 8-10, ethyl cellulose 4-6. The disadvantages of this composition are insufficient adhesion, low elasticity and gloss of coatings based on it.

Known is used as a floor covering decorative material obtained by laminating paper coated with a resin coating, cured by ionizing radiation, on paper, impregnated with thermosetting resin, and hot pressing, which contains a surface layer and a layer of base material, laminated and located on its outer side, which has a durable surface, abrasion resistant surface, resistance to subsidence, water resistance and oil resistance [6]. This mechanically durable coating has low electrical conductivity.

Known composition for coatings containing epoxy Dianova resin, aminophenol hardener, flotation reagent oxal based on ethers and formaldehyde of dioxane alcohols, titanium dioxide and an organic solvent, which to increase the elasticity, adhesion and gloss of the coating contains epoxy Dianova resin with an epoxy number of 22, as aminophenol hardener transamination product a mixture of 2- and 2,6 bis (dimethylaminomethyl) phenols with a mixture of diethylenetriamine, triethylenetetramine and N, b-aminoethylpiperazine, as an organ of a solvent, a mixture of ethyl acetate, butyl cellosolve, xylene and acetone in a mass ratio of (5-9): 1: (5-9): 1, respectively, and additionally dibutyl phthalate, chalk, block copolymer of propylene and ethylene oxides "Reapon", chloropolyol aliphatic trifunctional epoxy resin with an epoxy number of 6-8 and an average molecular weight of 2000 with a ratio of components, parts by weight: epoxy diane resin 100, aminophenol hardener 26, 34, flotation reagent oxal 8-15, titanium dioxide 30-50, dibutyl phthalate 3-5, chalk 70-110, reapon 3-5, a mixture of ethyl acetate, butyl cellulose vines, xylene and acetone 80-120 and chloropolyol aliphatic epoxy resin 10-18 [7].

The closest in technical essence and the achieved technical result (prototype) is a composition for protective wear-resistant at elevated temperatures and in corrosive environments coatings, including epoxy Dianova resin, amine hardener and cast iron powder, which contains epoxy Dianova resin with epoxy resin the content of 18-23% of the epoxy groups ED-20, as the amine hardener - polyethylene polyamine, and as cast iron powder, high-alloy nickel and copper cast iron the th powder of a fraction of 20-63 microns, heat-treated in argon at 250-300 ° C for 40-45 min, in the following ratio of components, parts by weight: epoxy diane resin 100-120, polyethylene polyamine 15-18, cast iron powder 400 -500 [8].

Common technical disadvantages of these coatings are low electrical conductivity and a non-smooth matte surface of the coating, low mechanical hardness and durability of coatings based on these compositions and practical unsuitability for subsequent powder coating using electrostatic deposition methods to obtain a highly aesthetic surface.

OBJECT OF THE INVENTION AND TECHNICAL RESULT

The aim of the invention and the technical result achieved by its use is to obtain a composition for the production of composite material and products with a protective and decorative coating of a dielectric material:

- with high protective properties in relation to the atmospheric effects of the environment in the form of sudden changes in temperature and humidity, heat, frost, as well as exposure to rain, wet snow and solar radiation,

- possessing high aesthetic characteristics of the surface,

- increasing the strength of the material in bending and torsion and surface mechanical stress,

- providing the possibility of subsequent high-quality painting and repainting of the material and products from it with powder paints by electrostatic deposition methods due to the high electrical conductivity of the coating.

SUMMARY OF THE INVENTION

The goal and the required technical result are achieved in that the composition for the formation of an electrically conductive protective and decorative coating of a dielectric material, including epoxy resin, hardener and metal powder, according to the invention contains a mixture of high molecular weight epoxy resins, mainly of type E-40 (TU 2225-154-05011907 -97) and E-05 (TU 2225-128-05034239-99) in the preferred mass ratio (90-86): (10-14) or Epicot 223 (Shell Corparation, Holland) and Epicot 401 (Shell Corparation, Holland) in the predominant mass ratio (87- 83) :( 13-17), an organic solvent, mainly in the form of a mixture of toluene, butanol (GOST 5208-81) and butyl acetate (GOST 8981-78) or xylene (GOST 9410), isopropyl alcohol (GOST 9805-84) and ethyl acetate (GOST 8981-78) in an advantageous mass ratio of 22:40:38, a hardener, mainly of a polyamide type, and a finely divided metal, mainly aluminum, powder.

The composition contains components in the ratio, parts by weight: high molecular weight epoxy resins 100-120, organic solvent 64-78, hardener 21-26 and finely divided metal powder 28-37.

Moreover, as a hardener of the polyamide type, the composition contains dimerized linseed oil acids with an acid number of 220 (PO-200 TU 2494-609-11131395-2005), and as a finely divided metal powder it contains a surface-modified finely dispersed aluminum powder treated by a countercurrent method in “boiling” layer ”of a vapor-gas phase with a critical surface energy of 40-45 erg / cm ² (PAP-2, GOST 5494-95).

Moreover, the composition further comprises a dispersant of a modified aluminum powder, for example, "Degussa R-3002" ("Degussa" R-3002, Degussa Evolonik Industries SKW, Trosberi, Germany), or "BYK 1413" (BYK-Chemie, Germany), and / or further comprises a stabilizer of a modified aluminum powder, for example, “BASF 04/118” (BASF Group, Germany).

The given quantitative indicators of the components of the composition are advantageous and in practice can vary within the indicated values, and other components with equivalent properties and components with similar properties, performing similar functions and allowing to obtain the required technical result can be used as separate components.

IMPLEMENTATION AND INDUSTRIAL APPLICABILITY

The composition according to the invention was used in an industrial environment in the manufacture of composite materials with a dielectric base and an electrically conductive protective and decorative coating and in the manufacture of products from dielectric materials with a protective and decorative coating.

Examples of the use of the composition in the manufacture of a composite material with a dielectric base and an electrically conductive protective and decorative coating and products made of them show significant hardening of the base surface, high resistance to moisture, weather and solar radiation, as well as the suitability of coatings for powder coating by electrostatic spraying.

Example 1. At a test site in the village of Otradnoye, Leningrad Region, an information stand was made with letters cut out from MDF fiberboard and painted with powder paint over a layer of the composition of the invention. After being on the street for more than 8 months, the letters retained a high gloss and tolerated winter and spring temperature changes, as well as summer heating by solar radiation.

Example 2. Two samples of MDF type MDF 50 × 50 mm in size were coated with one and two layers of coating from the composition and placed in a container with water, where they stayed afloat for 20 days without visual changes in geometric dimensions, which proves a significant increase in the moisture resistance of the substrate, since it is known that the MDF material is highly hygroscopic, as a result of which it rapidly increases its thickness due to capillary penetration of water by more than 1.2 times.

The measurement of the thickness of the test samples coated with one and two layers of the composition showed the equality of these values with the initial state before the samples were placed in water for 20 days.

Example 3. On the surface of MDF type MDF coated with the inventive composition and polymer powder paint painted on it, a lit cigarette was left, which burned to a complete cessation of decay (2-3 minutes), and it did not burn the integumentary surface, leaving it only dark track. This proves a significant increase in thermal conductivity and resistance of the obtained surface to thermal influences. The absence of fire or smoldering of the surface of the resulting new composite material is explained by the fact that the thermal conductivity of aluminum, which is part of the claimed composition is 190 [W / (m · K)], and MDF - 0.07 [W / (m · K)], i.e., the thermal conductivity of the coating from the composition is 2700 times higher than the thermal conductivity of the base of the MDF material, which provides a high level of heat removal of the surface from the composition when it is locally heated.

Example 4. The MDF plate was primed with the composition of the composition, and then coated with a hybrid powder paint and without curing put on storage to determine the time of loss (swelling) of the charge. After 30 days, the sample was shaken by hitting the floor with the end face of the plate. About 20 g of powder flew off a plate with an area of 1 m ² , but the appearance of the sample did not change, which proves the high ability of the composition to hold paint due to the high electrical conductivity of the surface electrostatic charge.

Example 5. The MDF plate was primed with the composition according to the composition and painted with powder paint with its polymerization, then cross-shaped incisions were made on the samples, and then tape was used to raise the edges of the cuts, but the edges of the coating cuts did not peel, which confirms the strong adhesion of the coating layers to the base. All high-quality painted products passed the tests according to GOST 15140-78 with an A2-70 adhesive meter.

Example 6. The MDF plate was primed with the composition of the composition and painted with powder paint, after which a metal ball was dropped from a height of 50 and 80 cm onto its surface. Under standard test conditions in accordance with ASTM D 2794, no dents were formed, which proves the high surface strength of the composite material and its products. All high quality painted products passed direct impact tests in accordance with ASTM D 2794.

The composition for the manufacture of material and products from it according to the invention is delivered complete in a metal container with a total mass of 20 kg

After delivery, all components used for the manufacture of protective and decorative coatings that form the basis of the composition — a solution of an epoxy resin mixture (component A) in an organic solvent, a hardener-catalyst (component B) and a filler — aluminum powder (component C), are kept in a paint preparation room in within 18-20 hours. The temperature of the components ready for use should not be lower than 18 ° C.

Weighing and dosing of the components is carried out on a balance with a measurement error of not more than 2%.

Component A is mixed with component C in an optimal ratio, and component C is poured gradually with constant stirring until a homogeneous mass of silver-gray color is obtained without lumps and clots.

The resulting mixture was incubated for 3 minutes, then the required amount of component B was added to it. The batch was thoroughly mixed for 10 minutes in the above manner.

The working viscosity of the resulting mixture should be 12-14 seconds using a B3-246 viscometer with a 4 mm nozzle. If a higher viscosity system is obtained, it can be diluted with a solvent prepared from a mixture of acetone (GOST 2768), ethyl cellulose (GOST 8313) and xylene (GOST GOST 9949) in a ratio, respectively, by weight,%: 30-30-40.

The prepared kneading of the components of the composition is suitable for use for at least 6 hours.

The composition prepared but not used for application on the material is stored in a tightly closed container in order to avoid volatilization of the solvent.

Transportation and storage of the components of the composition is carried out according to GOST 9980.5-86 at a temperature of 5 to 45 ° C, in a closed heated room.

Table 1 Main characteristics of the basis of the composition (component A) Name of indicator Norm Appearance Homogeneous viscous liquid, colorless or slightly colored Conventional viscosity of the base according to the VZ-246 viscometer with a nozzle diameter of 4 mm at a temperature of 20 + 0.5 ° C, s 13-19 Mass fraction of nonvolatile substances,% 34-40

table 2 Main characteristics of the hardener-catalyst (component B) Active substance content,%, not less than thirty Gelatinization time in terms of epoxy resin with epoxy equivalent 187-193, min, no more 90

In this case, gelatinization time is understood to mean the time after which a sharp increase in the viscosity of the mixture of resin with hardener begins.

Table 3 Key Features of Modified Aluminum Powder (Component C) Primary aluminum, brand, not lower A5 Granulometric composition - residue on a sieve +008,%, no more 1,0 Active aluminum content,%, not less than 90 The content of modifying additives,%, no more 4,5 Surfacing,%, not less 92

Table 4 Main technical characteristics of the composition Name of indicator Norm Test method The appearance of the coating uniform smooth visually The nominal viscosity of the base according to the viscometer B3-246 with a nozzle diameter of 4 mm at a temperature of 20 + 0.5 ° C, s 13-19 GOST 17537 Mass fraction of non-volatiles in the semi-finished product,% 34-40 GOST 17537 Drying time to a tack degree of 3 hours no more: GOST 6589 At T = 20 deg 6 At T = 90 degrees one Coating hardness according to the pendulum device TML, conventional units, not less 0.5 GOST 5233 Bending elasticity, mm, not less 2 GOST 6806 Coating strength upon impact on the U-1 device, cm, not less than 40 GOST 4765 Thermal resistance of the coating at T = 250 degrees, h, not less 3 The viability of the ready-to-use compound at T = 25 deg, h, at least 6 Hazard level fire and explosion hazard GOST 12.1007-76 Recommended air humidity, not higher than% 80 Hazard Class 3 GOST 12.1.007-76

Table 5 The main methods of coating various types of surfaces with a composition Surface type The method of surface preparation (operations) Application Method (optional) Number of layers Additional operations Fiberglass Grinding, dust removal, degreasing Brush
Paint Spray one no Plastic Degreasing Air Spray Airless Spray one no Mineral glass Degreasing Pneumatic spray
Dipping one no Wood Grinding dust removal Brush
Pneumatic spray 2 Grinding the first layer Sandwich plywood Edge grinding Dust removal Edge brush Calendering 2 Grinding the first layer Wood fiber board Grinding dust removal Brush
Pneumatic spray 2 Grinding the first layer Chipboard Dedusting Pneumatic spray
Filling one no Cement and cement-bonded particleboard Dedusting Air Spray Airless Spray one no Ceramics Dedusting Dipping
Filling one no Stone and brick Dedusting Brush
Pneumatic spray one no

The experiments showed that when painting MDF plates coated with this composition on one side, the opposite side (the reverse side of the spraying) is simultaneously stained by an aerosol cloud of powder powder in the spray booth and electrostatics. Particularly, the effect of staining the powder with an aerosol cloud is noticeable on paints with a low particle weight, for example, on paints of the Gatchina powder paint plant.

The curing of powder coatings takes place in a heat chamber on the surface of products treated with the composition. Moreover, the formation of a paint layer on the surface of the dielectric material occurs much faster than in the case of liquid paints, due to the fact that the process is not associated with the volatilization of the solvent or water. A paint film is formed from melts depending on temperature in just 12-20 minutes.

When using the composition in the production of composite material and products using it, a dielectric material having a fibrous structure, for example MDF, is heated to a temperature of 80-90 degrees and held for 10 minutes to remove moisture from the structure of the fibrous material. Recommended humidity before painting 3-6%.

Then the composition of the coating layer at a temperature of 18-20 degrees C is applied to the surface of the substrate.

The base with the coating layer cools to a temperature of 18-20 degrees C, while the linear dimensions of the coating layer of the surface are reduced, and part of the substance of the composition penetrates between the fibers or into the pores of the base, and the first phase of the polymerization of the composition occurs.

Then the base with the coating layer is placed in the heating chamber for the second phase of polymerization, during which the fibers of the base rise and the pores open in the coating surface.

After that, the surface of the coating is ground to cut the base fibers that have risen during the polymerization.

Then produce a repeated application of the composition, which closes the created pores.

The resulting composite material or products from it is again placed in the heating chamber to accelerate the polymerization of the coating layer, after which the surface is finished.

Then, if necessary, powder coating is performed by corona discharge or triboelectric device, providing a layer of powder paint and baking a layer of paint in a heating chamber at a temperature of 170 degrees C for 18 minutes.

The experiments showed the possibility of repainting made with the use of the composition of the material and products with a color change.

The high electrical conductivity of the coating from the composition allows the product to be repainted with a color change under the same conditions under which metal surfaces are traditionally painted with powder paints.

Thus, the possibility of achieving the desired technical result has been practically proved, namely, the possibility of obtaining a protective and decorative coating of a dielectric material from a composition:

- with high protective properties in relation to the atmospheric effects of the environment, for example, sudden changes in temperature and humidity, heat, frost, as well as exposure to rain, wet snow and solar radiation,

- possessing high aesthetic characteristics of the surface,

- increasing the strength of the material in bending and torsion and surface mechanical stress,

- providing the possibility of subsequent high-quality coloring of the material and products from it with powder paints by electrostatic deposition methods due to the high electrical conductivity of the coating.

COMPLIANCE WITH ELIGIBILITY CRITERIA

In General, given the novelty and non-obviousness of the invention, the materiality of all general and particular features of the invention, the feasibility of the invention and the achievement of the objectives set by the invention and the required technical result, the claimed invention meets all the eligibility requirements for inventions.

The analysis also shows that all the general and particular features of the inventions are essential, since each of them is necessary, and together they are not only sufficient to achieve the purpose of the inventions, but also allow the invention to be implemented in an industrial way and to achieve the required technical results.

INFORMATION SOURCES

1. Nikolaev A.F. Synthetic polymers and plastics based on them. M.-L.: Chemistry, 1966, p. 661.

2. Spark EV et al. Ship painting technology. L .: Shipbuilding, 1974, p. 80.

3. RU 2044019, C09D 163/02, publ. 1995.09.20.

4. RU 2271875, B05D 1/06, publ. 2006.03.20, initial applications US 01/51386 (10.26.2001), WO 02/42167 (05.30.2002).

5. A.c. USSR No. 1441763, cl. C09D 5/08, 1987.

6. RU 98103869, E04F 15/02, publ. 01.01.10.

7. RU 2071494, C09D 163/02, publ. 1997.01.01.

8. RU 2044019, C09D 163/02, publ. 1995.09.20 (prototype).

Claims (5)

1. Composition for the formation of an electrically conductive protective and decorative coating of a dielectric material, including epoxy resin, hardener and metal powder, characterized in that it contains a mixture of epoxy resins of type E-40 and E-05 in a mass ratio (90-86) :( 10- 14) or Epicot 223 and Epicot 401 in a mass ratio (87-83) :( 13-17), a mixture of organic solvents, mainly in the form of a mixture of toluene, butanol and butyl acetate or xylene, isopropyl alcohol and ethyl acetate in an advantageous mass ratio of 22:40 : 38, hardener polyam of the same type and metal powder, in the following mass ratio of components: a mixture of epoxy resins 100-120, a mixture of organic solvents 64-78, hardener 21-26 and metal powder 28-37. 2. The composition according to claim 1, characterized in that as the polyamide hardener contains dimerized linseed oil acids with an acid number of 220. 3. The composition according to claim 1, characterized in that the metal powder contains a surface-modified finely dispersed aluminum powder treated by the countercurrent method in a "fluidized bed" of a vapor-gas phase with a critical surface energy of 40-45 erg / cm ² . 4. The composition according to claim 1, characterized in that it further comprises a dispersant of aluminum powder, for example, "Degussa R-3002" or "BYK 1413". 5. The composition according to claim 4, characterized in that it further comprises a stabilizer of aluminum powder, for example, BASF 04/118.