RU2127537C1 - Material for heat-reflecting and fireproofing clothing and method of producing aluminum-bearing filler for such material - Google Patents

Abstract

FIELD: manufacture of material for protective clothing. SUBSTANCE: material has three layers: fibrous, sealing and metal-bearing layers. Sealing and metal-bearing layers are based on fluorine-containing elastomer. Metal-bearing layer contains aluminum-bearing filler and has thickness of 10-150 micron. Method involves mixing aluminum with fat acids; grinding commercial purity aluminum lumps with thickness of up to 100 micron; rubbing with fat phase of fat acids and solvent in ball mill to produce homogeneous pasty mass. Liquid phase contains fat acids and solvent, such as white spirit, used in the ratio of 1 - (150 - 300), and aluminum used in an amount of 5-15% by weight. Method further involves drying mixture till aluminum content in dry residue reaches 55-75%. EFFECT: simplified manufacture method, increased service life and improved heat-reflecting and fireproofing qualities. 3 cl

Description

 The invention relates to the field of protective equipment, in particular protective equipment - clothing for the protection of firefighters working in the fire zone, elevated temperatures and other extreme conditions.

State of the art
Known heat-protective clothing using material made with channels or pockets for pumping any coolants (air, water, etc.) or placed in pockets of dry ice, for example, a. with. USSR N 1097344, N 1755809 (Ml ⁶ : A 62 B, 17/00) - overalls with channels for pumping water; a. with. USSR NN 476868, 795527 (Ml ⁶ : A 41 D, 13/00), UK patent N 2248173 (Ml ⁶ : A 62 B, 17/00) - clothes with pumping through the internal air channels; GDR economic patent N 254525 (Ml ⁶ : A 62 B, 17/00) - heat-protective clothing, in the internal cavities of which dry ice is placed.

 The disadvantages of such clothing are its inefficiency in the absence or insufficient amount of coolant, the high cost of means of pumping the coolant, its limited use.

Also known are multilayer materials with heat-shielding properties, while the material has inner layers of cotton fabric, and external layers of inorganic fiber fabric, for example, a. with. USSR N 1240416, N 1795892 (Ml ⁶ : A 62 B, 17/00); German patent N 299702 (Ml ⁶ : A 62 B, 17/00); UK patent N2215183 (Ml ⁶ : A 62 B, 17/00); Japanese application N 60-49513 (Ml ⁶ : A 62 B, 17/00) and the like.

In addition to inorganic fibers, organic fiber and rubber fabrics are also used (for example, material according to European patent N 0240248 (Ml ⁶ : A 62 B, 17/00), where the flexible sheet material used in aerospace technology contains silicone rubber with a layer of ceramic fibers based on alumino-borosilicate. Vulcanized methyl vinyl silicone is used as rubber.

 The disadvantages of this class of materials are as follows: their relatively large weight, as well as the possibility of heating them to non-operational temperatures due to the accumulation of thermal energy due to the low reflectivity of these materials.

 A more progressive direction in the development of heat and flame retardant clothing is the use of metallized materials.

For example, German patent N 4010038 (Ml ⁶ : A 62 B, 17/00), where the suit has two layers - inner woolen with flame-retardant properties, and the outer one - knitted from modified arimide and polybenzylmethazolene and laminated with aluminum; German patent N 3604726 (Ml ⁶ : A 62 B, 17/00), where the outer layer is made of metallized polymer; German patent N 3602392 (Ml ⁶ : A 41 D, 13/00) - clothes from polyethylene and aluminum foil are proposed; US patent N 463947 (Ml ⁶ : A 41 D, 13/00) - the upper layer of metal clothing; UK patent N 2255707 (Ml ⁶ : A 41 D, 13/00), where it is proposed to cover the polyolefin on one side with polyethylene, and on the other with aluminum: European patent N 0171900 (Ml ⁶ : A 62 B, 17/00) - for flame retardant the fabric is coated with a fluorescent coating and a flexible reflective sheet material; French patent N 2489696 (Ml ⁶ : A 62 B, 17/00) - according to which it is proposed to make jumpsuits for firefighters from many layers of material with isothermal gaskets, and the top layer to be made of a soft metallized cloth; RF patent N 2008044 (Ml ⁶ : A 62 B, 17/00), in which the material consists of a fibrous base, which is coated in the form of a chromed polyamide film or a sprayed layer of aluminum.

The closest technical solution is a material for heat-protective clothing according to the patent of the Russian Federation N 2082469 (Ml ⁶ : A 62 B, 17/00), containing fibrous, heat-reflecting layers, as well as additional layers of filled fluororubber, located on both sides of the fibrous layer, and a layer of unfilled fluororubber located on the outer surface of the heat-reflecting layer in contact with its inner surface with one of the layers made of filled fluororubber and representing a metallized coating (this is solved adopted as a prototype).

 The disadvantages of the solutions listed above are their fragility: due to the small thickness of the metal layer, their integrity is easily violated and, in addition, at high temperatures and aggressive environments, their performance is reduced.

Known methods for producing metal-containing coatings, for example, a paint based on a resinous component with metal powder (Japanese application N 55-30554 μl ⁶ : C 09 D, 5/38); coating based on organic binder and powder metal (French application N 2289584 μl ⁶ : C 09 D, 5/38); heat-resistant paint containing 60% titanium dioxide, 30% finely divided aluminum and as a binder of 5% boric and phosphoric acid (Japanese application N 55-50993 μl ⁶ : C 09 D, 5/00).

 The closest to the proposed method for producing a metal-containing filler is the solution according to the application of France N 2333035 (Ml. C 09 D, 5/02), which protects the heat and reflective coating emulsion containing at least 2 wt.% Dry pigment based on aluminum and aqueous an emulsion of a fatty acid, for example, stearic, oleic acid or elaine and lanolin in a ratio of 1: 0.8-1-1.2.

 The disadvantages of these methods is the fact that the coating obtained in this way has a low reflection coefficient (up to 0.65).

Disclosure of Invention
The objective of the invention is to increase the resource of the material by reducing the abrasion of the material, simplifying manufacturing techniques while maintaining high heat and flame retardant properties.

 The problem is also achieved by the fact that in the material for heat and flame retardant clothing containing at least three layers: fibrous, sealing and metal-containing, the last two layers based on fluororubber, the metal-containing layer has an aluminum-containing filler and the layer is taken with a thickness of 10-150 microns. Moreover, a thickness of less than 10 μm is impractical, since it leads to a decrease in the reflective layer to a value at which a sharp drop in the reflection coefficient occurs. The increase in thickness> 150 μm leads to an unjustified increase in the thickness of the material, which worsens its bending properties, manufacturing technology is complicated, the weight of the clothing and its price increase.

 In addition, the task is achieved by the fact that in the method for producing an aluminum-containing filler, comprising mixing aluminum with fatty acids, pure aluminum in the form of a foil with a thickness of up to 100 μm is crushed, and then the mixture of crushed aluminum with fatty acids and a solvent is ground in a ball mill until a homogeneous paste-like mass, and the composition of the liquid phase: fatty acids and mineral spirits are taken in the ratio 1: (150-300), and the aluminum content in the liquid phase is 5-15 wt.%, then the mixture is dried to aluminum content in dry residue up to 55-75%.

The best embodiment of the invention
An example of a technology for producing material is the following method. On a heat-resistant base, for example, on TSSN, TSSN-M fiberglass, heated, for example, over a plate of a spreading machine (brand IVO-3220), a sealing undercoat is applied.

 The sealing sublayer can, for example, be made in the form of a solution of a rubber compound in a solvent (ethyl acetate, ethyl acetate) at a mass concentration of 1.3-1: 3.5.

 The rubber mixture can be made, for example, from rubber SKF-26 N, N'-bis-furylidene-hexamethylenediamine, magnesia burnt technical grade B, chalk naturally enriched (for example, rubber mixture grade 51-1712 NIIRP).

 Next, vulcanization of rubberized fabric in a vulcanization boiler.

 After vulcanization, a heat-reflecting liquid-based varnish composition is applied to a heated fabric with a sealing sublayer, which is obtained in the form of a mixture of a solution of rubber, for example, SKF-26 rubber in ethyl acetate with a mass ratio of 1: 7-1: 7.5 and an aluminum-containing filler, obtained by the proposed method.

 In this case, the liquid rubber is mixed with aluminum filler in the ratio: liquid rubber - 90-97 wt. hours, aluminum filler - 3-10 wt. h

 Less than 90 wt. including liquid rubber gives a heterogeneous mass of the mixture, because In this case, the aluminum filler does not completely dissolve in the varnish and it falls out.

 If you take liquid rubber more than 97 wt. o'clock - there will be no gloss of a covering (a little aluminum).

 The amount of aluminum filler is optimized in the range of 3-10 wt. h.: with values less than 3 wt. hours, the reflection coefficient sharply decreases; more than 10 wt. including filler leads to heterogeneity of the mixture.

 The essence of the method for producing aluminum filler consists in the following technological sequence: pure Al in the form of aluminum foil, for example, grades A-5, A-99 up to 100 microns thick, is crushed (for an example of a specific implementation, weighing 2.00 kg) and mixed with a mixture fatty acids, for example, with stearic acid (or palmetic) (0.06 kg) dissolved in white spirit - 18.9 kg, then the mixture is ground to a homogeneous mass and dried to 55-75% dry residue.

 In this case, the liquid phase: fatty acids and white spirit are taken in a ratio of 1: (150-300). The thickness of the aluminum foil to obtain a filler is taken up to 100 μm, since at a thickness> 100 μm, the aluminum particles obtained after grinding do not subsequently give a uniform filler layer due to their non-optimal orientation, which ultimately leads to a drop in reflection coefficient.

 The ratio in the composition of the liquid phase is chosen as indicated, since a smaller amount of white spirit does not provide the necessary purification of aluminum, and an increase in white spirit above the specified limit will lead to a lack of fatty acids and, therefore, to insufficient protection of aluminum from oxidation. The values of the aluminum content in the liquid phase were chosen experimentally, taking less than 5% aluminum is not advantageous, since the energy and time losses sharply increase at the drying stage, and more than 15% do not give a uniform mass at the mixing stage, and with aluminum over 15% it will oxidize , which will lead to a decrease in reflection coefficient.

 It is rational to dry the paste to 55-75% of the dry residue in the indicated range, since with a dry aluminum residue of less than 55% a more liquid, oily, combustible mixture is obtained, which is fire hazardous during storage and adversely affects mixing with rubber, i.e. at the same values of the reflection coefficient, it worsens the physical and mechanical properties of the coating (a thicker layer must be applied). With more than 75% solids, filler yield decreases, oxidation of aluminum particles begins, which leads to a decrease in reflection coefficient.

Industrial applicability
Tests of an experimental sample of fire-retardant material for firefighter clothing showed compliance of the material with the following indicators:
surface density, g / m ² - not more than 500 (in the prototype 700)
abrasion resistance, cycles - at least 1000 (in the prototype 300)
resistance to repeated bending, cycles - not less than 9000 (in the prototype 4500)
thickness, mm - 0.2-0.3 (in the prototype more than 1 mm)
resistance to negative temperatures C ^o - up to -60 ^o C (in the prototype -60 ^o C)
resistance to temperature 200 ^o C - at least 960 seconds (in the prototype 960 seconds)
resistance to open flame, s - at least 20 seconds (in the prototype 20 seconds)
reflection coefficient of infrared radiation,% - not less than 75% (in the prototype 70%)
resistance to heat flux 25 kW / m ² , s - at least 240 seconds (in the prototype 240 seconds)

Claims (2)

 1. Material for heat and flame retardant clothing containing fibrous, sealing and metal-containing layers, the last two layers based on fluororubber, characterized in that it contains at least three layers, and the metal-containing layer has an aluminum-containing filler, and the layer is taken with a thickness of 10 - 150 microns.  2. A method of producing an aluminum-containing filler, comprising mixing aluminum with fatty acids, characterized in that pure aluminum with a thickness of up to 100 μm is ground, then aluminum is ground with a liquid phase from fatty acids and a solvent in a ball mill to obtain a homogeneous pasty mass, and the composition of the liquid phase : fatty acids and a solvent in the form of white spirit are taken in the ratio 1 - (150 - 300), and the aluminum content in the liquid phase is 5 - 15 wt.%, then the mixture is dried to an aluminum content in the dry residue to 55 - 75 %