NL2016754B1 - Aircraft panel, in particular an aircraft window, and method of manufacturing such an aircraft panel - Google Patents

Abstract

The invention relates to an aircraft panel, in particular an aircraft window. The invention also relates to an aircraft, comprising at least one aircraft panel according to the invention, wherein the aircraft panel is preferably formed by an aircraft window. The invention then relates to a method for manufacturing an aircraft panel, in particular an aircraft window. according to the invention.

Description

Aircraft panel, in particular an aircraft window, and method of manufacturing such an aircraft panel

The invention relates to an aircraft panel, in particular an aircraft window. The invention also relates to an aircraft, comprising at least one aircraft panel according to the invention, wherein the aircraft panel is preferably formed by an aircraft window. The invention then relates to a method for manufacturing an aircraft panel, in particular an aircraft window, according to the invention.

A viewing window arranged in an aircraft, often also referred to as an aircraft window, is generally composed of an outer window and a plastic inner window positioned at a distance from the outer window. The inner frame is generally made of polycarbonate. A disadvantage of plastic interior windows is that they damage relatively quickly and are often relatively dull, which impedes the light transmittance, and therefore negatively influences the view through the viewing window.

A first object of the invention is to provide an improved interior window for an aircraft.

A second object of the invention is to provide a relatively transparent interior window for an aircraft.

A third object of the invention is to provide a relatively scratch-resistant aircraft panel.

A fourth object of the invention is to provide a relatively scratch-resistant and / or transparent aircraft panel with a relatively good impact resistance.

A fifth object of the invention is to provide an improved interior window for an aircraft that meets requirements set by the international aviation authorities with regard to fire resistance, self-extinguishing and smoke-generating properties.

At least one of the aforementioned goals, or a combination thereof, can be achieved by providing an aircraft panel of the type mentioned in the preamble, comprising: at least one ultra-thin chemically cured first glass plate with a maximum thickness of 1.25 mm; at least one impact-absorbing intermediate layer with a maximum thickness of 0.5 mm, which intermediate layer comprises at least one polymer, at least one polymer positioned between the first glass plate and the intermediate layer and comprising a first adhesive layer for mutually securing the first glass plate and the intermediate layer , at least one second glass plate, which second glass plate is positioned on a side of the intermediate layer remote from the first glass plate, and at least one polymer comprising a second adhesive layer positioned between the second glass plate and the intermediate layer for mutually securing the second glass plate and the intermediate layer. The aircraft panel according to the invention is particularly suitable for use as an inner window of an aircraft window in an aircraft. The aircraft panel according to the invention is formed by a laminate of material layers, of which at least one outer material layer is formed by a glass plate. Glass has a significantly greater scratch resistance than polycarbonate, which benefits the durability of the aircraft panel. Moreover, glass is a considerably clearer and more transparent material than polycarbonate, which can also improve the transparency of the aircraft panel. The first glass plate, and preferably also the second glass plate, have a maximum thickness of 1.25 mm and are therefore ultra-thin in order to limit the total weight of the laminate, which is relevant for the use of the aircraft panel according to the invention in a plane. Preferably, the weight of the aircraft panel according to the invention is equal to or less than the weight of the conventional inner window made of polycarbonate. Because the first glass plate, and preferably also the second glass plate, are chemically hardened and ultra-thin (<1.25 mm), the first glass plate, and preferably also the second glass plate, will be made considerably stronger and more flexible, which makes the impact resistance considerably increased and the risk of breakage considerably reduced. The impact resistance of the aircraft panel as such is further increased, because the laminate additionally comprises an impact-absorbing intermediate layer which ensures that in the event of an impact on a (chemically tempered) glass plate, the impact is partly absorbed by (temporary deformation of) the intermediate layer, which further reduces the risk of breakage, which is particularly advantageous from a safety point of view. In case of splintering (decomposition) of a glass plate during an impact on the glass plate, the glass splinters will be substantially completely retained by the application of the underlying adhesive layer, which is also particularly advantageous from a safety point of view. Since fire safety also plays an important role in aircraft panels, the combustible intermediate layer is also particularly thin (<0.5 mm) in order to keep the amount of combustible material in the aircraft panel according to the invention as limited as possible. Generally, the thickness of both the (combustible) first adhesive layer and (combustible) the second adhesive layer will be less than or equal to the thickness of the intermediate layer, whereby the flammability of the aircraft panel according to the invention is limited and complies with international standards and EASA regulations. . In particular, the aforementioned embodiment of the aircraft panel according to the invention, in contrast to the conventional polycarbonate panels, meets the "Airworthiness Standards" (Part 25) as prescribed by the Federal Aviation Administration (FAA), as well as the "Certification Specification" '-25 (CS-25), as prescribed by the European Aviation Safety Agency (EASA), and more particularly to the requirements 25,853 (a), 25,853 (d), 25,775 (a), and 25,785 (d), that form part of the aforementioned regulations. Regulation 25,853 (a) relates to multiple fire tests, including the "H2.5" test, the "V12" test, and the "V60" test, which successfully completes the aforementioned aircraft panel embodiment.

The aircraft panel according to the invention will generally be used as an interior window (aircraft window) of an aircraft window in an aircraft. However, it is also conceivable that the aircraft panel is used as a (different type of) partition panel and / or, in the case where said laminate also comprises a mirror layer, as a mirror in an aircraft. It is also conceivable to use the scratch-resistant, preferably particularly transparent, relatively fire-resistant, lightweight panel with relatively high impact resistance according to the invention in vessels and (land) vehicles, because also in these alternative vehicles aspects such as weight, scratch resistance, transparency, fire safety and impact resistance usually play an important role.

As already indicated, the second glass plate is preferably also chemically cured in order to increase the strength of the glass plate. In the chemical hardening of the first glass plate, and preferably also of the second glass plate, the (uncured) glass is preferably immersed in a bath with molten potassium nitrate at a temperature of approximately 400 ° C. This results in a chemical exchange of K + ions from the bath with the Na + ions from the glass. The K + ions (dimensions 2.66 A) take the place of the Na + ions (dimensions 1.96 A). Since these have larger dimensions, they induce compressive stresses on the surface of the glass, which can thus offer more resistance. The immersion duration is (also) a determining factor for the ultimate voltage level. The stress distribution does not have the same shape as with thermally tempered glass, and generally leads to significantly stronger glass, with a higher flexural strength, than if unhardened glass were to be thermally tempered. The chemical hardening of the glass plate can optionally be carried out in several steps, preferably for successively exchanging different selective ions, such as sodium ions, silver ions, copper ions and / or lithium ions for potassium ions. In this context, it is noted that chemically tempered glass generally has a much higher compressive stress on the surface of the glass plate which decreases relatively quickly just below the surface, with a limited tensile stress being present in the middle (1/2 depth) of the glass plate, so that a blocked voltage profile is created. Thermally tempered glass generally has a considerably lower compressive stress on the surface of the glass plate, with a relatively high tensile stress being present in the center of the glass plate, resulting in a parabolic stress profile.

The glass used for the glass plate preferably comprises aluminum oxide (Al2 O3), preferably in an amount of at least 7 mol%. Such glass is also referred to as aluminum silicate glass. It has been found that glass containing alumina, in particular if the amount of alumina comprises at least 7 mol%, will penetrate the potassium ions (K + ions) deeper into the glass plate, on average up to about 50 microns, which gives the thin glass plate a higher and thus improved flexural strength , usually about 800 MPa. The alumina content in the glass plate as used in the aircraft panel according to the invention is preferably between 7 and 25 mol%. The increased bending strength leads to a relatively strong and flexible glass that has a relatively high impact resistance and is not susceptible to vibrations. This makes the glass plate particularly suitable for use in and / or on an aircraft (or other type of vehicle). During curing, the potassium ions will penetrate the glass plate on two sides (on opposite (frontal) sides), whereby potassium ions are incorporated into the glass during the curing over a total thickness of 100 micrometres (2 x 50 micrometres). With a glass thickness of, for example, 1.0 millimeter, the total penetration depth is thus 10%. Thus, a surface layer of the first glass plate and / or the second glass plate will generally be chemically cured, and a core layer of the first glass plate and / or second glass plate will remain substantially unhardened. A further advantage of the use of Al2O3 in the glass plate is that the melting temperature of the glass plate can hereby be increased considerably, which is additionally advantageous from the viewpoint of fire safety. It is also conceivable to use soda lime glass instead of aluminum silicate glass. Natron kal kg weld can be chemically cured in the same manner as described above. Before chemically curing the first glass plate and / or second glass plate, the peripheral edge of the first glass plate and / or the second glass plate is preferably ground or otherwise finished. Because of this edge finishing, sharp, protruding edge parts can for instance be removed before the glass plate is hardened. After chemical curing, it is practically no longer possible, or at least not easy, to realize this edge finish.

The first glass plate of the aircraft panel is generally turned towards persons present on the aircraft (passengers and / or crew). The thickness of the first glass plate is preferably greater than or equal to the thickness of the second glass plate. The glass plates are preferably both ultra-thin (<1.25 mm), in order to provide the glass plates with a relatively flexible character, which reduces the risk of breakage, and wherein the glass plates will break up in relatively small glass particles in the event of breakage. (glass splinters), which is particularly advantageous from a safety point of view. Moreover, such a small thickness also has the advantage that the total weight of the aircraft panel will remain limited, which is relevant and advantageous from an economic and logistical point of view. Moreover, in this way the optical distortion of the aircraft panel will remain limited, which is pleasant for people looking out through the aircraft panel. The thickness of at least one glass plate is preferably smaller than 1.25 mm, more preferably 1.0 mm or smaller, in particular (approximately) 0.55 mm. The lower limit of the thickness of the first glass plate and / or the second glass plate will generally be 0.4 mm, in order to be able to manufacture the glass plate in a controlled manner.

The first adhesive layer and / or second adhesive layer preferably has a maximum thickness of 0.4 mm. The thickness is preferably at most 0.2 mm, more preferably at most 0.1 mm, and is in particular approximately 0.05 mm. It is generally advantageous to use an adhesive layer that is as thin as possible, as this reduces the flammability of the aircraft panel. The first adhesive layer, and preferably also the second adhesive layer, preferably have a maximum Young's modules of 2100 MPa. Due to this small Young's modulus, the adhesive layers have a relatively flexible character, which is advantageous for absorbing an impact exerted on the aircraft panel. Preferably, the first adhesive layer and / or the second adhesive layer have a elongation at break of at least 500%, preferably at least 1,000%. Such a high elongation at break prevents the adhesive layers from tearing relatively quickly, as a result of which the aircraft panel as such can be kept intact for longer.

In a preferred embodiment, the first adhesive layer and / or the second adhesive layer comprises a thermoplastic polymer. Preferably, the first adhesive layer and / or the second adhesive layer comprises a polymer selected from the group consisting of: ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU), and polyvinyl butyral (PVB). EVA is generally preferred for the intended use in an aircraft, since EVA is the least flammable of the aforementioned polymers. If TPU is used as a polymer in the first adhesive layer and / or second adhesive layer, then if the panel is used as an (inner) window, it is preferable to use an aliphatic TPU, since this is essentially colorless, and in the case of panel is not used as a window, but as a different partition panel and / or mirror, then it is generally preferable to use an aromatic TPU. An aromatic TPU has a yellow color, but is less flammable than an aliphatic TPU. It is conceivable here to (consciously) provide the intermediate layer with a color, so that the panel can also be used, for example, as a sun protection panel.

Preferably, the first adhesive layer and / or the second adhesive layer are substantially completely transparent. With the adhesive layers it is advantageous if the Haze is less or equal to 1% measured in accordance with ASTM E430 and ISO13803. De Haze is normative for the degree of transparency and in particular relates to an (undesired) optical effect caused by microscopic structures or a residue on a surface (measured in accordance with ASTM E430 and ISO13803).

The impact-absorbing intermediate layer preferably comprises a thermoplastic polymer. The impact-absorbing intermediate layer preferably comprises a polymer selected from the group consisting of: polyethylene terephthalate (PET), polyvinyl chloride (PVC), polycarbonate (PC), and polytetrafluoroethylene (PTFE). Such thermoplastics are substantially transparent with the property of being able to absorb an impact relatively well, making these polymers particularly suitable for use as one or in an intermediate layer. In order for the intermediate layer to be able to adhere better to the adjacent layers, usually formed by the first adhesive layer and the second adhesive layer, it is generally advantageous to subject the intermediate layer to a surface treatment before laminating the intermediate layer with the other material layers to the actual aircraft panel. This surface treatment can be formed, for example, by a plasma treatment. In order to reduce the combustibility of the intermediate layer (and / or at least one adhesive layer), which is advantageous from a safety point of view, it is preferable if the intermediate layer (and / or at least one adhesive layer) comprises at least one fire-retardant additive. This additive prevents the spread of fire, or at least prevents the spread of fire. The additive is preferably formed by an organohalogen compound. Such compounds are capable of removing reactive H and OH radicals during a fire. The organohalogen compound preferably comprises bromine and / or chlorine. From a fire retardant point of view, an organobromo compound, such as PBDE (polybrominated diphenyl ether), is preferable to an organochloro compound, such as PCB (polychlorinated biphenyl). Other examples of useful brominated compounds are: tetrabromobisphenol A, decabromodiphenyl ether (Deca), octabromobiphenyl ether, tetrabromobiphenyl ether, hexabromocyclododecane (HBCD), tribromophenol, bis (tribromophenoxy) ethane, tetrabromobisphenol A (polycarbonate TB) TB polycarbonate TB polycarbonate TB

Tetrabromobisphenol A epoxy oligomer (TBBA or TBBPA), and Tetrabromophthalic anhydride. Other examples of suitable chlorinated compounds are: chlorinated paraffin, Bis (hexachlorocyclopentadieno) cyclooctane, Dodecachloropentacyclodecane (Dechlorane), and 1,2,3,4,7,8,9,10,13,13,14,14-dodecachlor 1,4,4a, 5,6,6a, 7,10,10a, 11,12,12a-dodecahydro-1,4: 7,10-dimethanodibenzo (a, e) cyclooctene (Dechlorane Plus). However, from an environmental and economic point of view, preference is generally given to the non-use of an organohalogen compound in the intermediate layer. Such an organohalogen compound-free intermediate layer that is sufficiently fire-resistant can be realized by making the intermediate layer sufficiently thin, preferably by maintaining a maximum thickness of 150 micrometers.

The thickness of the intermediate layer is preferably between 0.1 and 0.5 mm. A thicker intermediate layer is undesirable from the point of view of fire safety. If the intermediate layer is fire-resistant, for example by adding one or more of the aforementioned additives, the intermediate layer may be thicker than if the intermediate layer was not fire-resistant. The thickness of a fire-resistant intermediate layer is preferably between 200 and 500 micrometers. The thickness of a non-fire-resistant intermediate layer is preferably between 100 and 150 micrometers. The intermediate layer preferably has a break elongation of at least 200%, which is sufficient to be able to absorb a significant impact. The density of the intermediate layer preferably has a density that is less than or equal to 1.5 g / cm 3. Higher density materials make the aircraft panel undesirably heavy. The intermediate layer preferably has a maximum Young's modulus of 4150 MPa. The intermediate layer will generally be (somewhat) stiffer than the first adhesive layer and the second adhesive layer, but just sufficiently flexible to be able to absorb an impact sufficiently. Instead of a polymer-containing intermediate layer, it is also conceivable to use a glass-containing intermediate layer. The glass-containing intermediate layer can optionally here be formed by a glass plate, whether or not chemically cured. The maximum thickness of this intermediate (third) glass plate is preferably also 1.25 mm, more preferably 1.0 mm, and in particular approximately 0.55 mm.

It is conceivable and may be advantageous if at least one additional layer is positioned between the first glass plate and the second glass plate, preferably selected from the group consisting of: an electrochromatic layer, a thermochromatic layer, a mirror layer, an opaque layer, and an opaque layer, and further glass plate. The mirror layer can be of various designs. It is conceivable in this connection that the mirror layer is designed as an at least one-sided reflective film. The advantage of a foil is that the layer thickness of the mirror layer is substantially homogeneous, which can benefit a homogeneous reflection of the mirror. It is also conceivable that a (thin) metal (oxide) layer is applied to another layer of the laminate, which other supporting layer is preferably formed by the glass plate. Examples of suitable metals are copper, silver, gold, nickel, aluminum, Berillium, chromium, molybdenum, platinum, rhodium, tungsten, and titanium. The metal layer can be applied to the supporting layer, in particular the glass plate, by means of vacuum vapor techniques and / or sputtering. Optionally, the applied metal layer can be removed at least in part, for example by sandblasting, in order to make a part of the mirror completely or semi-transparent and / or to provide the mirror with a satinized (mat) appearance. This makes it possible to generate visual effects behind the mirror layer, for example in a separate material layer, which will be visible via the semi-transparent mirror for people looking into the mirror. The aforementioned examples of the mirror layer concern embodiments in which the (static) mirror layer is permanently mirrored. In a preferred embodiment, a side of the mirror layer remote from the glass plate is at least partially provided with a coating protecting the mirror layer. The coating is particularly advantageous if the mirror layer is formed by a metal layer in order to be able to prevent or at least prevent oxidation of the metal layer. If the mirror layer is formed by a copper layer, for example, it is conceivable to coat the copper layer with an inhibitor based on, for example, azole derivative. However, it is also conceivable that the mirror layer has a semi-permanent (temporary) mirroring design. The mirror layer can generally be made reflective as desired. This is possible, for example, by having at least a part of the mirror layer formed by an electrochromatic layer. By connecting the electrochromatic layer, possibly based on liquid crystals (LCD), to an electrical energy source, such as a battery, the layer can be charged, whereby the mirroring layer can be activated or deactivated. The electrochromatic layer can optionally be laminated during the production process. It is also conceivable to later assemble such a layer with the laminate already formed. It is conceivable to position the thermochromatic layer behind a possibly non-reflective, possibly anti-reflective, part of the mirror, in particular of the glass plate.

The aircraft panel according to the invention can have a substantially flat geometry, but if the aircraft panel is used as an inner window of an aircraft window, it will generally have a single (or multiple) curved geometry, depending on the design of the aircraft window, in particular the design of a frame of the aircraft window that is adapted to hold the inner window.

The invention also relates to a vehicle, in particular an aircraft, comprising at least one aircraft panel according to the invention. In this case at least one aircraft panel is preferably used if aircraft window is used, more preferably such that the first glass plate is turned towards, the second glass plate is turned away from a space enclosed by the aircraft. The aircraft panels can optionally also be used as a separation panel, video screen, touch screen (touchscreen), mirror and / or combinations thereof. Vehicles are understood to include motorcycles, automobiles, vessels and aircraft (aircraft).

The invention further relates to a method for manufacturing an aircraft panel according to the invention, comprising the steps of: A) providing a first glass plate with a thickness of 1.25 mm; B) machining a peripheral edge of the first glass plate; C) chemically curing the first glass plate; D) cleaning the first glass plate, E) positioning on the first glass plate: a polymer comprising first adhesive layer, an impact-absorbing intermediate layer with a maximum thickness of 0.5 mm, which intermediate layer comprises at least one polymer, comprising a polymer second adhesive layer, and a second glass plate; F) subjecting the assembly of layers formed during step E) to an underpressure as well as to a temperature profile with an elevated temperature while forming a laminate. The time period t is preferably between 90 and 270 minutes. During step F), the temperature is preferably increased stepwise, more preferably by at least 40 degrees per step until a final temperature is reached. For example, a temperature step can be applied every 30 minutes.

A typical maximum temperature is above the glass temperature of the polymeric materials used, and will usually be between 100 and 200 degrees Celsius. Preferably, a temperature profile is applied during step F) with an average temperature rise of approximately 1 degree Celsius per minute. It may be advantageous to gradually release the underpressure during step F), upon reaching the maximum temperature. Further advantages and embodiments of the obtained laminated aircraft panel according to the invention have already been described in detail in the foregoing.

The invention will be elucidated on the basis of non-limitative exemplary embodiments shown in the following figures. Herein: figure 1 schematically shows a side view of an aircraft panel according to the present invention; Figure 2 schematically an aircraft panel, designed as an aircraft window, according to the present invention; Figure 3 schematically a method for manufacturing an aircraft panel then the present invention

Figure 1 shows schematically a side view of an aircraft panel (1) according to the invention. The panel (1) comprises a first ultra-thin chemically cured glass plate (2), with a maximum thickness of 1.25 mm, and a second glass plate (3), which is optionally also chemically cured. The glass is, for example, an aluminosilicate, which material is hard and does not break quickly. Such a glass comprises, for example, 15-25% Al2 O3 and 50-60% SiO2. The glass can also comprise 15-35% alkaline earth metal (Beryllium, Magnesium, Calcium, Strontium, Barium, Radium) to improve the chemical hardening of the glass. For example, the glass has a Young’s modulus between 60 and 80 GPa.

The chemical hardening of the glass plate (2) ensures that the glass becomes particularly strong, and also ensures, for example, that if the glass plate should break, splintering is prevented and / or that the glass splinters formed are relatively small. The chemical hardening takes place, for example, by immersing the glass plate (2) in a bath of molten salt, at a high temperature, for example around 400 degrees Celsius. Possible processing steps of the glass plate (2) preferably take place prior to chemical hardening, since the hardening of the glass counteracts further processing of the glass. After the glass plate (2) has been chemically cured, it is washed, for example, by ultrasonic washing, so that the glass plate (2) is clean and can adhere better to subsequent material layers.

Between the two glass plates (2, 3) there is a polymeric intermediate layer (4), with a maximum thickness of 0.5 mm. The intermediate layer (4) has an impact-absorbing effect. The intermediate layer (4) is made, for example, of fire-retardant polyethylene terephthalate (PET), polyvinyl chloride (PVC), polycarbonate (PC), or polytetrafluoroethylene (PTFE or Teflon). The intermediate layer (4) is preferably transparent, so that the panel can be used as a transparent window. The intermediate layer (4) is preferably also fire-retardant, for example by using halogens in the intermediate layer (4). The thickness of the intermediate layer is usually between 100 and 500 micrometers. The density of the intermediate layer (4) is usually between 0.9 and 1.5 grams per cubic cm. In an alternative embodiment, the intermediate layer (4) is a central glass plate (4).

The intermediate layer (4) is connected to the two glass plates (2, 3) by means of two polymeric adhesive layers (5, 6). The adhesive layers (5, 6) are made of, for example, ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU) or polyvinyl butyral (PVB). The thickness of the adhesive layers (5, 6) is preferably as thin as possible, and less than 0.38 mm, in particular less than 0.2 mm. The adhesive layer (5, 6) is generally relatively combustible, whereby reducing the thickness, and therefore the amount of adhesive material, limits the fuel present for a possible fire. For example, an adhesive layer (5, 6) of EVA has a Young's Modulus between 0.01 and 0.05 GPa. EVA is relatively poorly flammable compared to TPU and PVB, and therefore a preferred material for a fire-retardant aircraft panel (1).

The adhesive layers (5, 6) are also preferably transparent, for use of the panel in an aircraft window. For this purpose, the adhesive layers have, for example, a low turbidity, so that it is light-transmitting at least 95%, in particular at least 99%.

Figure 2 schematically shows a part of an aircraft (11) provided with an aircraft panel (12), or aircraft window (12) according to the present invention. The panel will generally be curved. Additional advantages of the applied panel according to the invention, in addition to being light in weight and having a relatively high impact resistance, are having a relatively homogeneous light transmittance, the high degree of scratch resistance, and having a uniform thickness so that the light refraction is also relatively uniform.

Figure 3 schematically shows the method for manufacturing an aircraft panel (21) then the present invention. The method has the steps of: A) providing a first glass plate (22) with a thickness (d) of 1.25 mm; B) machining a peripheral edge (27) of the first glass plate (22); C) chemically curing the first glass plate (22), for example by immersing the glass plate (22) in a molten salt bath; D) cleaning the first glass plate (22), E) positioning on the first glass plate (22) a polymer comprising first adhesive layer (25), an impact-absorbing intermediate layer (24) with a maximum thickness of 0.5 mm, said intermediate layer (24) comprising at least one polymer, a polymer comprising second adhesive layer (26), and a second glass plate (23); F) subjecting the formed assembly of layers (22-26) to an underpressure (P) as well as to a temperature profile (T) with an elevated temperature to form a laminate for a period of time t.

Processing of the peripheral edge (27) of the first glass plate (22) takes place before the first glass plate (22) is chemically cured. This is because it is easier to process for hardening the glass plate (22). The cleaning of the first glass plate (22) takes place, for example, by placing the glass plate in an ultrasonic bath, wherein sound waves are driven through the bath. Ultrasonic cleaning of the glass plate (22) has the advantage that no scratches occur on the glass plate (22), that the entire glass plate (22) is cleaned and that cleaning can take place relatively quickly.

For example, subjecting the assembly layers (22-26) to an underpressure (P) takes place under vacuum. The temperature (T) to which the assembly of layers (22-26) is subjected is, for example, about 105 degrees Celsius.

The assembly of the assembly layers (22-26) and / or subjecting the assembly to an underpressure and elevated temperature takes place, for example, in a clean room. Preferably, a temperature between 18 and 23 degrees Celsius is maintained in such a space, with a relative humidity of approximately 20 percent. In such circumstances, proper laminating of the material layers takes place.

It will be clear that the invention is not limited to the exemplary embodiments shown and described here, but that within the scope of the appended claims, countless variants are possible which will be obvious to those skilled in the art. It is conceivable in this connection that different inventive concepts and / or technical measures of the above-described embodiment variants can be fully or partially combined without thereby renouncing the inventive idea described in the appended claims.

The verb "to include" and conjugations thereof used in this patent not only means "to include", but also the terms "to contain", "essentially exist", "formed by", and conjugations thereof.

Claims (26)

An aircraft panel, in particular an aircraft window, comprising: at least one ultra-thin chemically cured first glass plate with a maximum thickness of 1.25 mm; at least one impact-absorbing intermediate layer with a maximum thickness of 0.5 mm, which intermediate layer comprises at least one polymer, at least one polymer positioned between the first glass plate and the intermediate layer and comprising a first adhesive layer for mutually securing the first glass plate and the intermediate layer , at least one, preferably chemically cured, second glass plate, which second glass plate is positioned on a side of the intermediate layer remote from the first glass plate, and at least one polymer-bonded second adhesive layer positioned between the second glass plate and the intermediate layer of the second glass plate and the intermediate layer. The aircraft panel of claim 1, wherein the thickness of the first glass plate is greater than or equal to the thickness of the second glass plate. The aircraft panel of claim 1 or 2, wherein the first adhesive layer and / or the second adhesive layer comprises a polymer selected from the group consisting of: ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU), and polyvinyl butyral (PVB). Aircraft panel according to any one of the preceding claims, wherein the first adhesive layer and / or the second adhesive layer has a maximum Young's modules of 2100 MPa. Aircraft panel according to any one of the preceding claims, wherein the intermediate layer comprises a polymer selected from the group: polyethylene terephthalate (PET), polyvinyl chloride (PVC), polycarbonate (PC), and polytetrafluoroethylene (PTFE). Aircraft panel according to any one of the preceding claims, wherein a surface layer of the first glass plate and / or the second glass plate is chemically cured, and wherein a core layer of the first glass plate and / or the second glass plate is substantially unhardened. Aircraft panel according to any one of the preceding claims, wherein the first glass plate and / or the second glass plate is made of aluminum silicate glass or soda lime glass. Aircraft panel as claimed in any of the foregoing claims, wherein the first glass plate has a maximum thickness of 1.0 mm, preferably 0.7 mm, more preferably 0.55 mm, in particular 0.4 mm. Aircraft panel according to any one of the preceding claims, wherein the peripheral edge of the first glass plate and / or the second glass plate are ground. Aircraft panel as claimed in any of the foregoing claims, wherein the first adhesive layer and / or second adhesive layer have a maximum thickness of 0.4 mm, preferably 0.2 mm, more preferably 0.1 mm, in particular 0.05 mm . Aircraft panel according to any one of the preceding claims, wherein the first adhesive layer and / or the second adhesive layer are transparent. Aircraft panel according to any one of the preceding claims, wherein the first adhesive layer and / or the second adhesive layer have a maximum Haze of 1% measured in accordance with ASTM E430 and ISO13803. Aircraft panel according to any one of the preceding claims, wherein the first adhesive layer and / or the second adhesive layer is at least partially made from a thermoplastic. Aircraft panel as claimed in any of the foregoing claims, wherein the first adhesive layer and / or the second adhesive layer have a elongation at break of at least 500%, preferably at least 1,000%. Aircraft panel according to any one of the preceding claims, wherein the thickness of the intermediate layer is between 0.1 and 0.5 mm. Aircraft panel according to any one of the preceding claims, wherein the intermediate layer is transparent. Aircraft panel according to any one of the preceding claims, wherein the intermediate layer has a fracture elongation of at least 200%. Aircraft panel as claimed in any of the foregoing claims, wherein the intermediate layer comprises at least one fire-retardant additive, wherein the at least one fire-retardant additive is preferably formed by an organohalogen compound. Aircraft panel according to any one of the preceding claims, wherein the intermediate layer has a density that is smaller than or equal to 1.5 g / cm 3. Aircraft panel according to any one of the preceding claims, wherein the intermediate layer has a maximum Young's modules of 4150 MPa. Aircraft panel according to any one of the preceding claims, wherein the second glass plate is thicker than the first glass plate. Aircraft panel according to any one of the preceding claims, wherein at least one additional layer is positioned between the first glass plate and the second glass plate, selected from the group consisting of: an electrochromatic layer, a thermochromatic layer, a mirror layer, an opaque layer, and an opaque layer, and further glass plate. Aircraft panel according to one of the preceding claims, wherein the aircraft panel is curved. An aircraft, comprising at least one aircraft panel according to any one of the preceding claims. Aircraft according to claim 24, wherein at least one aircraft panel is used as an aircraft window, such that the first glass plate faces the, the second glass plate faces away from a space enclosed by the aircraft. A method of manufacturing an aircraft panel according to any of claims 1-23, comprising the steps of: A) providing a first glass plate with a thickness of 1.25 mm; B) machining a peripheral edge of the first glass plate; C) chemically curing the first glass plate; D) cleaning the first glass plate, E) positioning on the first glass plate: a. A polymer comprising first adhesive layer, b. an impact-absorbing intermediate layer with a maximum thickness of 0.5 mm, which intermediate layer comprises at least one polymer, c. a polymer comprising a second adhesive layer, and d. a second glass plate; F) subjecting the assembly of layers formed during step E) to an underpressure as well as to a temperature profile with an elevated temperature while forming a laminate.