Composite element and use thereof

Abstract

A lightweight composite pane is provided that includes a mineral glass or glass-ceramic pane and an organic layer. The weight per unit area of the lightweight composite pane is in the range from 0.5 kg/m.sup.2 to 5.5 kg/m.sup.2, the ratio of the thickness of the mineral glass pane to the thickness of the organic layer is 1:0.01 to 1:1, and the thickness of the organic layer is less than or equal to 500 m. The lightweight composite pane meets the thermal safety requirements of aerospace authorities and has a Total Heat Release, measured in compliance with JAR/FAR/CS 25, App. F, Part IV & AITM 2.0006, of less than 65 kWmin/m.sup.2 and a flame time, after removal of the flame in the Vertical Bunsen Burner Test, measured in compliance with FAR/JAR/CS 25, App. F, Part 1 & AITM 2.0002A, is less than 15 seconds.

Claims

1. A lightweight composite pane for viewing windows, comprising: a mineral glass pane, wherein the mineral glass pane is prestressed and has a glass pane refractive index; an organic layer adjacent the mineral glass pane, wherein organic layer has an organic layer refractive index; a weight per unit area having a lower limit of 0.5 kg/m.sup.2 and an upper limit of 5.5 kg/m.sup.2; a ratio of a thickness of the mineral glass pane to a thickness of the layer is 1:0.01 to 1:1, wherein the thickness of the layer is less than or equal to 450 m; and an absolute heat release, measured in compliance with JAR/FAR/CS 25, App. F, Part IV & AITM 2.0006, of less than 65 kWmin/m.sup.2, wherein the glass pane refractive index and the organic layer refractive index have a difference therebetween that is less than or equal to 0.3, wherein the organic layer comprises a duroplastic reaction resin that is a polymer selected from the group consisting of phenoplasts, phenol formaldehyde resins, aminoplasts, urea formaldehyde resins, melamine formaldehyde resins, epoxide resins, unsaturated polyester resins, vinyl ester resins, phenacrylate resins, diallyl phthalate resins, cross-linking polyurethane resins, polymethacrylate reaction resins, and polyacrylate reaction resins, and any combinations thereof.

2. The lightweight composite pane according to claim 1, wherein the lower limit is greater than or equal to 1 kg/m.sup.2, the upper limit is less than or equal to 3 kg/m.sup.2, the ratio is 1:0.01 to 1:0.9, the thickness of the layer is less than or equal to 350 m, and the absolute heat release of less than 50 kWmin/m.sup.2.

3. The lightweight composite pane according to claim 1, further comprising a fire protection property with a flame time after removal of the flame in the vertical Bunsen burner test, measured in compliance with FAR/JAR/CS 25, App. F, Part I, of less than 15 s.

4. The lightweight composite pane according to claim 1, further comprising a transparency of greater than 80%.

5. The lightweight composite pane according to claim 1, further comprising an optical scattering behavior of less than or equal to 1.5%.

6. The lightweight composite pane according to claim 1, wherein the thickness of the mineral glass pane is less than or equal to 1 mm and greater than or equal to 200 m.

7. The lightweight composite pane according to claim 1, wherein the mineral glass pane is selected from the group consisting of a lithium aluminum silicate glass, a soda-lime silicate glass, a borosilicate glass, an alkali aluminosilicate glass, an alkali-free aluminosilicate glass, a low-alkali aluminosilicate glass, a chemically hardened lithium aluminum silicate glass, a chemically hardened soda-lime silicate glass, a chemically hardened borosilicate glass, a chemically hardened alkali aluminosilicate glass, a chemically hardened alkali-free aluminosilicate glass, a chemically hardened low-alkali aluminosilicate glass, a thermally hardened lithium aluminum silicate glass, a thermally hardened soda-lime silicate glass, a thermally hardened borosilicate glass, a thermally hardened alkali aluminosilicate glass, a thermally hardened alkali-free aluminosilicate glass, and a thermally hardened low-alkali aluminosilicate glass.

8. The lightweight composite pane according to claim 1, wherein the mineral glass pane is a mineral glass-ceramic pane selected from the group consisting of a ceramicized aluminosilicate glass, a ceramicized lithium aluminosilicate glass, a chemically hardened ceramicized aluminosilicate glass, a chemically hardened ceramicized lithium aluminosilicate glass, a thermally hardened ceramicized aluminosilicate glass, and a thermally hardened ceramicized lithium aluminosilicate glass.

9. The lightweight composite pane according to claim 8, wherein the mineral glass pane is a chemical hardened mineral glass-ceramic pane having an ion-exchange depth of greater than or equal to 30 m.

10. The lightweight composite pane according to claim 1, wherein the mineral glass pane has a surface compressive stress that is greater than or equal to 500 MPa.

11. The lightweight composite pane according to claim 1, wherein the mineral glass pane has an internal tensile stress that is less than or equal to 50 MPa.

12. The lightweight composite pane according to claim 1, wherein the mineral glass pane has a 4-point bending strength that is greater than or equal to 550 MPa.

13. The lightweight composite pane according to claim 1, wherein the mineral glass pane has a modulus of elasticity that is greater than or equal to 68 GPa.

14. The lightweight composite pane according to claim 1, wherein the mineral glass pane has a sheer modulus that is greater than or equal to 25 GPa.

15. The lightweight composite pane according to claim 1, wherein the mineral glass pane has a Vickers hardness that is greater than or equal to 550 HV 2/20.

16. The lightweight composite pane according to claim 1, wherein the layer further comprises fillers.

17. The lightweight composite pane according to claim 1, wherein the layer has a transparency that is greater than 80%, the lightweight composite pane further comprising a haze that increases by less than 1% owing to the layer.

18. The lightweight composite pane according to claim 1, wherein the layer has an outward-facing surface having a waviness of less than or equal to 100 nm and a roughness R.sub.T of less than or equal to 30 nm.

19. The lightweight composite pane according to claim 1, wherein the layer has an optical retardation that is not greater than 20 nm.

20. The lightweight composite pane according to claim 1, wherein the layer has a streak that is less than 100 nm.

21. The lightweight composite pane according to claim 1, wherein the layer has a modulus of elasticity that is less than 5 GPa.

22. The lightweight composite pane according to claim 1, further comprising a difference in a refractive index of the mineral glass pane and the layer that is less than or equal to 0.3.

23. The lightweight composite pane according to claim 1, wherein the mineral glass pane is thermally prestressed, chemically prestressed, or a combination of thermally and chemically prestressed.

24. A lightweight composition pane for viewing windows according to claim 1, wherein the difference between the refractive index of the glass pane and the refractive index of the organic layer is less than or equal to 0.2.

25. A lightweight composition pane for viewing windows according to claim 1, wherein the difference between the refractive index of the glass pane and the refractive index of the organic layer is less than or equal to 0.15.

26. A lightweight composition pane for viewing windows according to claim 1, wherein the refractive index for the glass pane is between 1.508 and 1.52 at 588 nm wavelength.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The sole FIGURE shows the structure of a lightweight composite pane.

DETAILED DESCRIPTION

(2) The invention shall be explained in detail by way of the following examples.

(3) The FIGURE shows the structure of a lightweight composite pane 1. The base support substrate is formed by a first glass pane 11 made of a chemically prestressed aluminosilicate glass, such as the one offered by the company Schott A G/Mainz under the trade name Xensation, which has a thickness of 0.55 mm and a density of 2.48 g/cm.sup.3; as the organic layer A 21, a polymethyl methacrylate with a thickness of 150 m and a density of 1.19 g/cm.sup.3, was used. There resulted a weight per unit area of 1.54 kg/m.sup.2 and hence a weight savings of 35% in comparison to a standard window pane made of pure PC or PMMA in an aircraft interior cabin with 2.4 kg/cm.sup.2 as reference value. The ratio of the thickness of the glass pane to the thickness of the organic layer was 1:0.273. This lightweight composite pane 1 passed the Bunsen burner test, which was carried out in compliance with the provisions and regulations of FAR/JAR/CS 25, App. F, Part I & AITM 2.0002A. And they passed the heat release test. This test was carried out in compliance with the provisions and regulations of FAR/JAR/CS 25, App. F, Part IV & AITM 2.0006.

(4) The following Examples 2 and 3 show alternative embodiments of a lightweight composite pane, corresponding to the embodiment of FIG. 1, that passed the Bunsen burner test and the heat release test.

EXAMPLE 2

(5) TABLE-US-00010 Material Thickness Glass layer Chemically prestressed aluminosilicate glass 1.0 mm Organic layer Polyurethane with flame-retarding additive, 200 m applied in the RIM method

(6) Weight per unit area: 2.72 kg/m.sup.2.

(7) Ratio of the thickness of the glass pane to the total thickness of the organic layer:

(8) 1:0.200.

EXAMPLE 3

(9) TABLE-US-00011 Material Thickness Glass layer Chemically prestressed aluminosilicate glass 0.2 mm Organic layer Silicone resin 100 m

(10) Weight per unit area: 0.60 kg/m.sup.2.

(11) Ratio of the thickness of the glass pane to the total thickness of the organic layer: 1:0.500

LIST OF REFERENCE NUMBERS

(12) TABLE-US-00012 1 Lightweight composite pane 11 Glass pane 21 Organic layer