RU2495839C1 - Composition for aviation glass articles based on oriented organic glass - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to glass used in aviation. The surface of oriented organic glass is coated with a layer of colourless lacquer with thickness of 5-6 mcm based on polymethyl phenyl silsesquioxane grafted to nano-sized silicon dioxide globules. Further, two layers of an alloy of indium-tin oxides are deposited, with a gold layer in between. A 4-5 mcm thick ground coat based on chlorinated polyolefins, which is coated with polymer material, is then deposited on the layer of an alloy based on indium-tin oxides.

EFFECT: attenuation of electromagnetic radiation and solar heat, low reflection coefficient while maintaining high adhesion of materials made from the composition to both the surface of glass and with each other, high abrasive resistance and weather resistance.

1 tbl, 1 dwg

Description

The invention relates to the field of manufacturing aviation glazing compositions based on oriented organic glass, which is widely used in aircraft manufacturing.

The operational efficiency and flight performance of the aircraft sufficiently depend on the technical level of the glazing used in them, which today does not fully meet the necessary requirements.

So, due to the technical features of the radar and navigation equipment of the aircraft, flight personnel are exposed to the powerful effects of electromagnetic radiation (EMP) in excess of the permissible sanitary standards. In addition, glazing does not provide protection against the penetration of the thermal component of solar radiation.

The problem of attenuation of thermal radiation is especially relevant when operating equipment in tropical or hot, dry climates. The flight personnel of the aircraft experiences powerful heat loads, which slow down the reaction of pilots and their susceptibility to the environment.

Under certain weather conditions, glare may occur on the glass, which interferes with the operational and accurate orientation of the aircraft relative to the runway during the landing process (especially when landing a combat aircraft on an aircraft carrying cruiser).

For military aviation, an urgent task is also, in addition to all of the above, a decrease in the radar visibility of glazing.

Protection against electromagnetic radiation is also relevant for radio and television broadcasting rooms, mobile communications, etc.

The solution to these problems lies in creating an effective composition on the glazing surface based on oriented organic glass, which provides the maximum attenuation of electromagnetic radiation and solar heat, reducing radar imperceptibility. It is very important that the materials included in the composition have a sufficiently high adhesion to oriented organic glass and to each other, as well as high resistance to external factors (abrasion and moisture resistance).

Known composition used to attenuate electromagnetic radiation, solar heat and reduce radar invisibility according to patent JP 62041740, IPC C03C 17/23; C03C 17/36, publ. 02/23/1987. This composition contains metal oxide in contact with the surface of the glass, a second layer of noble metal and a third upper layer of metal oxide. In this case, tin, indium, zinc and antimony oxides are used as metal oxides. Silver, gold, copper, palladium and rhodium are used as precious metals.

A disadvantage of the known composition is that the metal oxides from the above group have poor adhesion to organic glass, in particular to oriented organic glass of the AO-120 brand, which is widely used in the manufacture of aircraft glazing products. Therefore, after 2-3 weeks, the coating of metal oxide peels off the surface of organic glass.

Closest to the invention is a composition used to attenuate electromagnetic radiation, solar heat and containing a transparent lower layer and alternating dielectric layers from the group of indium, zinc, tin oxides or their alloys and an infrared-reflecting metal layer from the group: silver, gold, copper or their alloys according to the application WO 9928258, IPC C03C 17/36, publ. 06/10/1999. Moreover, the composition contains an outer coating layer of glass or a transparent polymeric material.

A disadvantage of the known composition is that the metal oxides from the above group have poor adhesion to organic glass, in particular to oriented organic glass of the AO-120 brand, which is widely used in the manufacture of aircraft glazing products. In addition, the outer coating layer of glass or a polymeric material also has poor adhesion to metal oxides of this group - they do not withstand adhesive tape testing (testing consists in sticking adhesive tape to the surface and then abruptly tearing it off the surface).

The objective of the invention is to obtain a composition of aircraft glazing products based on oriented organic glass to attenuate electromagnetic radiation, solar heat and reduce radar invisibility while achieving satisfactory adhesion of the materials of the composition to both the surface of organic glass and the materials constituting it relative to each other.

To achieve the objective of the invention, there is provided a composition comprising oriented organic glass, two layers of an alloy of indium and tin oxides located on its surface, between which a layer of gold is located, and an outer layer of an alloy of indium and tin oxides is coated with a transparent layer of a polymeric material, characterized in that the composition additionally contains a layer of colorless varnish on the glass surface 5-6 μm thick based on polymethylphenylsilsesquioxane grafted to nanosized globules of creme dioxide Nia and the primer layer having a thickness of 4-5 microns based on chlorinated polyolefins, located between layers of oxide alloy and a polymeric material.

An additional layer of colorless varnish with a thickness of 5-6 μm, located on the surface of organic glass, obtained on the basis of polymethylphenylsilsesesquioxane grafted to nanosized globules of silicon dioxide, provides satisfactory adhesion both to the surface of organic glass and to a layer of an alloy of indium and tin oxides. In turn, a primer layer with a thickness of 4-5 microns, obtained on the basis of chlorinated polyolefins, located between the layers of an alloy of indium and tin oxides and a polymeric material, provides satisfactory adhesion between these layers.

Figure 1 - composition of aircraft glazing based on oriented organic glass.

The composition contains a sheet of oriented organic glass 1 with predetermined geometric parameters (Fig. 1 shows flat glass, but it can also be bent). On the surface of glass 1 is a layer of colorless varnish 2 with a thickness of 5-6 microns, obtained on the basis of polymethylphenylsilsesquioxane grafted to nanosized globules of silicon dioxide. Between layers 3, consisting of an alloy of indium and tin, is a layer 4, consisting of gold, while layers 3 and 4 are made with nanoscale thickness. The primer layer 5 with a thickness of 4-5 microns, obtained on the basis of chlorinated polyolefins, is located between the layers of an alloy of oxides and polymer material 6.

Example 1. On the surface of oriented organic glass of the AO-120 brand with specified geometric parameters, a layer of colorless varnish is applied based on polymethylphenylsilsesquioxane grafted to nanosized globules of silicon dioxide. After polymerization of the varnish during heat treatment, the thickness of the varnish coating is determined using a micrometer, which is 5-6 microns over the entire glass area. Next, glass with a varnish layer is installed in a vacuum magnetron installation with magnetrons and targets of an indium-tin and gold alloy placed in it, the working space of the installation is evacuated, after which layers are alternately applied to the varnish layer: indium-tin oxide alloy; gold; indium tin oxide alloy. To obtain indium-tin alloy oxides, oxygen is supplied to the working zone of the installation. The thickness of the layers is measured using a control system containing a high-speed spectrophotometer and a calculation-synthesizing program unit. When the aggregate layer thickness is 90 nm, the process of applying layers is stopped. Then, a primer layer of 4-5 microns thick, obtained on the basis of chlorinated polyolefins, is applied to the outer layer of an indium-tin oxide alloy. After that, a layer of colorless varnish with a thickness of 5-6 μm, obtained on the basis of polymethylphenylsilsesquioxane, grafted onto nanosized globules of silicon dioxide is applied.

Aircraft glazing based on oriented organic glass, obtained according to example 1, were tested on special stands and installations. The test results are shown in table 1.

Table 1 Name of the measured parameter, unit Value Tape Testing No separation of layers from glass The attenuation coefficient of the heat flux of solar radiation in the wavelength range of 0.9-2.5 microns,% Not less than 40 Attenuation of the flux density of electromagnetic radiation, dB 20-25 Reflection coefficient in the wavelength range of 400-740 nm,% No more than 6 Light transmittance in the wavelength range of 400-740 nm,% Not less than 65 The absorption coefficient of radar waves,% 40 ± 10 Abrasion resistance, rpm 3000 Moisture resistance, hydrolytic class one

From the data shown in table 1, it is seen that the proposed composition of aircraft glazing based on oriented organic glass provides high performance in attenuating electromagnetic radiation and solar heat, in reducing reflection coefficient, and also in absorbing radar waves, while maintaining a high level integrated light transmission of products in the visible spectrum.

Along with the above positive factors, the proposed composition of the products provides the necessary adhesion of the materials of the composition both to the surface of organic glass and relative to each other. This ensures high abrasion resistance and weather resistance of products obtained with the proposed composition.

Information sources

1. Patent JP 62041740, IPC C03C 17/23; C03C 17/36, publ. 02/23/1987.

2. Application WO 9928258, IPC C03C 17/36, publ. 06/10/1999 - a prototype.

Claims (1)

A composition comprising oriented organic glass, two layers of an indium tin oxide alloy located on its surface, between which a gold layer is located, the outer layer of an indium tin oxide alloy coated with a transparent layer of polymeric material, characterized in that the composition further comprises a layer of colorless varnish on the glass surface 5-6 μm thick based on polymethylphenylsilsesesquioxane grafted to nanosized globules of silicon dioxide and a primer layer 4-5 microns thick on the base ove chlorinated polyolefins disposed between layers of an alloy of indium-tin oxide and a polymeric material.

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