Thin glass substrate, method and apparatus for its production

Patent metadata

Field	Value
Publication number	US-12005687-B2
Application number	US-202318171925-A
Country	US
Kind code	B2
Filing date	Feb 21, 2023
Priority date	Dec 22, 2016
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

A thin glass substrate, as well as a method and an apparatus are provided. The glass substrate has a glass having first and second main surfaces and elongated elevations on one of the main surfaces. The elevations rise in a normal direction, have a longitudinal extent that is greater than two times a transverse extent, and have a height, on average, that is less than 100 nm, and with a transverse extent of the elevation smaller than 40 mm. The method includes melting a glass, hot forming the glass, and adjusting a viscosity of the glass so that for the viscosity η1 for a first stretch over a first distance of up to 1.5 m downstream of a flow rate control component and y1 indicating a second distance to a location immediately downstream the flow rate control component the equation lg η1(y1)/dPa·s=(lg η01/dPa·s+a1(y1)) applies.

First claim

What is claimed is:

1. A glass substrate, comprising:
a glass having first and second main surfaces; and
elongated elevations on one of the first and second main surfaces, the elongated elevations substantially rising in a normal direction, having a longitudinal extent that is greater than two times a transverse extent, and having a height, on average, that is less than 100 nm, and with a transverse extent of the elevation smaller than 40 mm.

2. The glass substrate of claim 1 , further comprising a substantially wedge-shaped thickness variation with a value of less than 100 μm over a length of 1 m perpendicular to a drawing direction.

3. The glass substrate of claim 1 , further comprising a warpage with a value of less than 600 μm over a length of 1 m perpendicular to a drawing direction.

4. The glass substrate of claim 1 , further comprising a mean thickness from 0.5 mm to 2.6 mm averaged over a surface area of the first and second main surfaces of at least 10 cm*10 cm.

5. The glass substrate of claim 1 , wherein the glass is selected from a group consisting of an Li-Al-Si glass, an Al-Si glass, a borosilicate glass, and a K-Na-Si glass.

6. The glass substrate of claim 1 , wherein the glass is a lithium-aluminum silicate glass having an Li 2 O content from 4.6 wt % to 5.4 wt %, an Na 2 O content from 8.1 wt % to 9.7 wt %, and an Al 2 O 3 content from 16 wt % to 20 wt %.

7. The glass substrate of claim 1 , wherein the glass substrate has a thickness of up to 10 mm.

8. The glass substrate of claim 1 , wherein the glass substrate has a thickness of up to 12 mm.

9. A laminated glass pane comprising a first glass sheet laminated to a glass substrate having first and second main surfaces, and elongated elevations on one of the first and second main surfaces, the elongated elevations substantially rising in a normal direction, having a longitudinal extent that is greater than two times a transverse extent, and having a height, on average, that is less than 100 nm, and with a transverse extent of the elevation smaller than 40 mm.

10. The laminated glass pane of claim 9 , wherein the first glass sheet is a lithium-aluminum silicate glass sheet having an Li 2 O content from 4.6 wt % to 5.4 wt %, an Na 2 O content from 8.1 wt % to 9.7 wt %, and an Al 2 O 3 content from 16 wt % to 20 wt %.

11. The laminated glass pane of claim 9 , wherein the laminated glass pane is configured for a use selected from a group consisting of a motor vehicle glazing, a windscreen projection device, and a head-up display.

Assignees

• Schott Ag

Inventors

• Vogl Armin
• Schmiady Thomas
• Zachau Thilo
• Alkemper Jochen
• Meister Michael
• Kunert Christian
• Klippe Lutz
• Dietrich Rüdiger

Classifications

• Y10T428/24777

  Edge feature · CPC title

• B32B3/26

  characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids {(foam layer B32B5/18; layer of synthetic resin characterised by fillers that create voids or cavities B32B27/205); characterised by an apertured layer} · CPC title

• B32B3/02

  characterised by features of form at particular places, e.g. in edge regions {(non-uniform thickness B32B3/263)} · CPC title

• C03C3/093

  containing zinc or zirconium · CPC title

• C03B23/023

  by bending · CPC title