Method for producing a curved composite glass pane having a thin glass pane

Abstract

A method for producing a composite glass pane, includes placing a first glass pane having a thickness less than or equal to 1 mm on a support mould, wherein the first glass pane is curved into a shape determined by the support mould; placing at least one thermoplastic film on the first glass pane; placing a curved second glass pane having a thickness greater than or equal to 1.5 mm on the thermoplastic film; and joining the first glass pane to the second glass pane via the thermoplastic film to form a composite glass pane by lamination.

Claims

1. A method for producing a composite glass pane, comprising: placing a first glass pane having a thickness less than or equal to 1 mm on a support mould, wherein the first glass pane is curved into a shape determined by the support mould; placing at least one thermoplastic film on the first glass pane; placing a curved second glass pane having a thickness greater than or equal to 1.5 mm on the at least one thermoplastic film; and joining the first glass pane to the second glass pane via the at least one thermoplastic film to form a composite glass pane by lamination, wherein the support mould has a plurality of support pins, on which the first glass pane rests in a substantially point-wise manner.

2. The method according to claim 1, wherein the support mould is convex.

3. The method according to claim 1, wherein the support mould has at least five support pins.

4. The method according to claim 1, wherein at least two support pins are heatable.

5. The method according to claim 1, wherein the support pins are movable independently of one another.

6. The method according to claim 1, wherein the first glass pane is sucked against the support mould by application of a negative pressure and is thus curved.

7. The method according to claim 1, wherein the first glass pane is chemically tempered.

8. The method according to claim 1, wherein the first glass pane is made of aluminosilicate glass and the second glass pane of soda lime glass.

9. The method according to claim 1, wherein the at least one thermoplastic film contains polyvinyl butyral, ethylene vinyl acetate, or polyurethane.

10. The method according to claim 1, wherein the second glass pane has a thickness of 1.5 mm to 5 mm.

11. The method according to claim 1, wherein the first glass pane has a thickness of 0.2 mm to 1.0 mm.

Description

(1) The invention is explained in detail with reference to drawings and exemplary embodiments. The drawings are a schematic representation and not true to scale. The drawings in no way restrict the invention. They depict:

(2) FIG. 1 a plan view of an embodiment of the support mould according to the invention with the first glass pane placed thereon,

(3) FIG. 2 a cross-section through the support mould of FIG. 1,

(4) FIG. 3 a plan view of another embodiment of the support mould according to the invention with the first glass pane placed thereon,

(5) FIG. 4 a cross-section through the support mould of FIG. 3,

(6) FIG. 5 a cross-section through the support mould of FIG. 3 with the entire layer stack placed thereon before lamination,

(7) FIG. 6 an exemplary embodiment of the method according to the invention using a flowchart.

(8) FIG. 1 and FIG. 2 depict in each case a detail of an embodiment of the support mould 4 according to the invention. The support mould 4 has a substantially full-surface contact surface, which is interrupted only by small openings 5. A first glass pane 1 is arranged on the contact surface of the support mould 4. The first glass pane 1 is, for example, a 0.6-mm-thick, chemically tempered pane made of aluminosilicate glass.

(9) The convex contact surface of the support mould 4 has a curvature that corresponds to the desired curvature of the composite glass pane. The first glass pane 1 is planar in the initial state, adapts due to its low thickness and the associated flexibility to the contact surface, and is bent at ambient temperature without active heating (cold bent).

(10) The openings 5 can be connected to a means for generating a negative pressure, for example, a fan or a vacuum pump. Thus, suction can be generated, by means of which the first glass pane 1 is sucked against the contact surface of the support mould 4.

(11) FIG. 3 and FIG. 4 depict in each case a detail of another embodiment of the support mould 4 according to the invention. The support mould 4 has, in this embodiment, no large-area contact surface, but, instead, a plurality support pins 6. The upper ends of the support pins 6 define a curved surface, whose curvature corresponds to the desired curvature of the composite glass pane. A first glass pane 1 rests substantially point-wise on each support pin 6; a large-area direct contact between the support mould and the glass pane 1 is avoided.

(12) If some or all support pins 6 are heatable, the layer stack can be adhesively bonded locally in the region of the support points. Thus, a local adhesive bond can be produced such that a type of pre-laminate is created and the layer stack is stabilised in its curved form and can be removed from the support mould 4.

(13) The curvature can be modified by a vertical displacement of the support pins 6 relative to one another. Thus, one and the same support mould 4 can be used for producing composite glass panes of different types.

(14) FIG. 5 depicts a cross-section through a layer stack for lamination on a support mould 4 as in FIG. 4. Apart from the first glass pane 1 on the support pins 6, the layer stack comprises a thermoplastic film 3 on the first glass pane 1 and a second glass pane 2 on the thermoplastic film 3. The thermoplastic film 3 is, for example, a 0.76-mm-thick PVB film. The second glass pane 2 is, for example, a 2.1-mm-thick pane of soda lime glass. The second glass pane 2 is, due to its thickness, not sufficiently flexible to be cold bent and is, consequently, already pre-bent into the final shape by means of conventional bending methods, for example, by compression bending.

(15) The support mould 4 ensures uniform contact pressure within the layer stack. The subsequent lamination results in a composite glass pane with high optical quality and without critical tendencies for delamination.

(16) FIG. 6 depicts an exemplary embodiment of the method according to the invention for producing a composite glass pane using a flowchart.

LIST OF REFERENCE CHARACTERS

(17) (1) first glass pane (2) second glass pane (3) thermoplastic film (4) support mould (5) opening in the support surface of the support mould 4 (6) support pin of the support mould 4 A-A′ section line B-B′ section line