Method for heating molten glass and glass article

Patent metadata

Field	Value
Publication number	US-12157696-B2
Application number	US-202217748393-A
Country	US
Kind code	B2
Filing date	May 19, 2022
Priority date	Nov 21, 2019
Publication date	Dec 3, 2024
Grant date	Dec 3, 2024

Abstract

A glass article is designed at least in part in the form of a glass tube element including at least one shell which encloses at least one lumen. For at least one light transmission analysis of the glass article, a ratio of an average amplitude transmission factor and a specific amplitude transmission factor is greater than 1.00001.

First claim

What is claimed is:

1. A glass article, the glass article being designed at least in part in the form of a glass tube element comprising at least one shell which encloses at least one lumen, wherein for at least one light transmission analysis of the glass article, a ratio of an average amplitude transmission factor and a specific amplitude transmission factor is greater than 1.00001, wherein for the light transmission analysis, an outer surface of the at least one shell is at least virtually divided into surface areas of equal shape and size, and an amplitude transmission factor of a light beam, which is emitted from a fixed light source towards a fixed detector along a beam path, is determined consecutively for every surface area in that the glass article and/or the surface area is positioned relative to the beam path such that the light beam propagates through a thickness of the at least one shell and crosses the respective surface area perpendicularly, wherein the amplitude transmission factors of all surface areas are arranged within a sorted list from small values to large values, wherein the specific amplitude transmission factor is the mean value of the first 1% of the amplitude transmission factors arranged in the sorted list, the smallest one being among the first 1% of the amplitude transmission factors, wherein the average amplitude transmission factor is the mean value of all amplitude transmission factors arranged in the sorted list, wherein the average amplitude transmission factor is larger than or equal to 0.99;
wherein the amplitude transmission factor is the factor the amplitude of the light beam is attenuated between the light source and the detector;
wherein the light beam has a wavelength of between 270 nm and 300 nm;
wherein the light source comprises a laser; and
wherein the outer surface of the at least one shell is divided in 10 or more equal surface areas, wherein the at least one shell has an overall average concentration of molybdenum, platinum, iridium, tungsten, rhodium, noble metals, alloys of one or more of these materials or oxides of one or more of these materials, respectively, of at least 0.1 ppm (m/m) but less than 50 ppm (m/m).

2. The glass article according to claim 1 , wherein the average amplitude transmission factor is larger or equal to 0.993.

3. The glass article according to claim 1 , wherein the specific amplitude transmission factor is smaller than or equal to 0.9999.

4. The glass article according to claim 1 , wherein the ratio is greater than 1.00003.

5. The glass article according to claim 1 , wherein the glass article has a length of between 1 m and 3 m.

6. The glass article according to claim 1 , comprising in weight percent

SiO 2
50-90

B 2 O 3
 0-20

Al 2 O 3
>0-18

Na 2 O
 0-15

K 2 O
0-5

Li 2 O
0-2

CaO
 0-15

BaO
0-6

ZrO 2
0-5

TiO 2
0-5

Fe 2 O 3
 0-3.

7. A glass article, the glass article being designed at least in part in form of a glass tube element comprising at least one shell which encloses at least one lumen, wherein for at least one light transmission analysis of the glass article, a ratio of an average amplitude transmission factor and a specific amplitude transmission factor is greater than 1.00003, wherein for the light transmission analysis, an outer surface of the at least one shell is at least virtually divided into surface areas of equal shape and size, and an amplitude transmission factor of a light beam, which is emitted from a fixed light source towards a fixed detector along a beam path, is determined consecutively for every surface area in that the glass article and/or the surface area is positioned relative to the beam path such that the light beam propagates through a thickness of the at least one shell and crosses the respective surface area perpendicularly, wherein the amplitude transmission factors of all surface areas are arranged within a sorted list from small values to large values, wherein the specific amplitude transmission factor is the mean value of the first 1% of the amplitude transmission factors arranged in the sorted list, the smallest one being among the first 1% of the amplitude transmission factors, wherein the average amplitude transmission factor is the mean value of all amplitude transmission factors arranged in the sorted list;
wherein the at least one shell has an overall average concentration of molybdenum, platinum, iridium, tungsten, rhodium, noble metals, alloys of one or more of these materials or oxides of one or more of these materials, respectively, of at least 0.1 ppm (m/m) but less than 50 ppm (m/m);
wherein the amplitude transmission factor is the factor the amplitude of the light beam is attenuated between the light source and the detector;
wherein the light beam has a wavelength of between 270 nm and 300 nm;
wherein the light source comprises a laser; and
wherein the outer surface of the at least one shell is divided in 10 or more equal surface areas.

8. The glass article according to claim 7 , wherein the specific amplitude transmission factor is smaller than or equal to 0.9999.

9. The glass article according to claim 7 , wherein the glass article has a length of between 1 m and 3 m.

10. The glass article according to claim 7 , comprising in weight percent

SiO 2
50-90

B 2 O 3
 0-20

Al 2 O 3
>0-18

Na 2 O
 0-15

K 2 O
0-5

Li 2 O
0-2

CaO
 0-15

BaO
0-6

ZrO 2
0-5

TiO 2
0-5

Fe 2 O 3

Assignees

• Schott Ag

Inventors

• Eichholz Rainer Erwin
• Rasp Josef
• Hahn Michael
• Knoche Stefan

Classifications

• C03B5/033

  by using resistance heaters above or in the glass bath, i.e. by indirect resistance heating · CPC title

• C03C3/091 Primary

  containing aluminium · CPC title

• C03C2203/10

  Melting processes · CPC title

• C03C2201/54

  containing beryllium, magnesium or alkaline earth metals · CPC title

• C03C2201/50

  containing alkali metals · CPC title