LAMINATE OF A THICK POLYMER MATERIAL SHEET AND OF A THIN GLASS SHEET

Abstract

A glazing includes a transparent polymer material sheet having a thickness of from 5 to 25 mm and a glass sheet having a thickness of between 0.5 and 1.5 mm, which are bonded to one another by an adhesive interlayer, the hardness of which at a temperature at least equal to −5° C. is at most equal to 70 Shore A and the thickness of which is a decreasing function of the thickness of the glass sheet, an adhesive interlayer thickness of 2.5 mm being sufficient for a glass sheet thickness of 0.55 mm and an adhesive interlayer thickness of 1.25 mm being sufficient for a glass sheet thickness of 1.25 mm.

Claims

1. A glazing essentially consisting of a transparent polymer material sheet having a thickness of from 5 to 25 mm and a glass sheet having a thickness of between 0.5 and 1.5 mm, which are bonded to one another by an adhesive interlayer, a hardness of the adhesive interlayer at a temperature at least equal to −5° C. is at most equal to 70 Shore A and a thickness of the adhesive interlayer is a decreasing function of a thickness of the glass sheet, an adhesive interlayer thickness of 2.5 mm being sufficient for a glass sheet thickness of 0.55 mm and an adhesive interlayer thickness of 1.25 mm being sufficient for a glass sheet thickness of 1.25 mm.

2. The glazing as claimed in claim 1, wherein the transparent polymer material is selected from poly(methyl methacrylate) and polycarbonate.

3. The glazing as claimed in claim 1, wherein the thickness of the glass sheet is at most equal to 1.4 mm.

4. The glazing as claimed in claim 3, wherein the thickness of the glass sheet is at most equal to 1.3 mm.

5. The glazing as claimed in claim 4, wherein the thickness of the glass sheet is at most equal to 1.2 mm.

6. The glazing as claimed in claim 5, wherein the thickness of the glass sheet is at most equal to 1.1 mm.

7. The glazing as claimed in claim 6, wherein the thickness of the glass sheet is at most equal to 1.0 mm.

8. The glazing as claimed in claim 1, wherein a thickness of the transparent polymer material sheet is at most equal to 20 mm.

9. The glazing as claimed in claim 8, wherein the thickness of the transparent polymer material sheet is at most equal to 15 mm.

10. The glazing as claimed in claim 9, wherein the thickness of the transparent polymer material sheet is at most equal to 12 mm.

11. The glazing as claimed in claim 1, wherein a face of the glass sheet oriented toward the adhesive interlayer bears a heating layer.

12. The glazing as claimed in claim 1, wherein the adhesive interlayer(s) is (are) selected from thermoplastic polyurethane, polyvinyl butyral, ethylene/vinyl acetate and a resin such as

13. The glazing as claimed in claim 1, wherein said transparent polymer material sheet is monolithic or consists of several plies laminated together.

14. A method comprising mounting a glazing as claimed in claim 1 on a terrestrial, airborne or water-borne transport vehicle, a surface of which in contact with the external atmosphere consists of said glass sheet,

15. The glazing as claimed in claim 12, wherein the resin is an ionomer resin.

Description

EXAMPLE

[0018] A 9 mm thick sheet of poly(methyl methacrylate) is bonded to a 0.55 mm or 1.25 mm thick sheet of soda-lime-silica float glass chemically strengthened by an adhesive interlayer having a thickness of 1.25 mm or 2.5 mm consisting of polyvinyl butyral which is compatible with the PMMA, sold by Saflex under the registered trademark Saflex® PVB DB, or of thermoplastic polyurethane sold by Huntsman under the registered trademark Krystalflex® PE 499.

[0019] At 20° C., the hardness of Saflex® PVB DB is 95 Shore A and that of the Krystalflex® PE 499 TPU is 65 Shore A.

[0020] Six laminated glazings are assembled, having the features recorded in the table below.

TABLE-US-00001 Thickness of Thickness of Thickness of Thickness of Sample no. glass mm PVB mm TPU mm PMMA mm 1 0.55 1.25 0 9 2 0.55 0 1.25 9 3 0.55 2.5 0 9 4 0.55 0 2.5 9 5 1.25 1.25 0 9 6 1.25 0 1.25 9

[0021] These six laminates are subjected to the polarized light test (plane polariscope) which makes it possible to visualize the stresses in the laminate.

[0022] This test consists in exposing the sample to a source of polarized light and in observing the sample through a polarized filter.

[0023] The stress levels in the material are shown by the observation of color fringes known as isochromatics.

[0024] A zero stress level gives a black color; when the stress levels increase, the cold colors (blue, green) decrease in order to give way to hot colors (yellow, red).

[0025] An absence of stresses is only observed for the laminated glazings 4 and 6. It guarantees that the bimaterial strip effect described above does not occur, and that rippling of the thin glass sheets should not be expected for the laminated glazings 4 and 6. This is in accordance furthermore with direct visual observation through these glazings or using a shadow technique: specifically, no rippling is seen on the laminated glazings 4 and 6, unlike the other laminated glazings.