Coloured stove sightglass with colour-neutral transmission characteristics

• US 11,059,739 B2
• Filed: 12/21/2018
• Issued: 07/13/2021
• Est. Priority Date: 12/22/2017
• Status: Active Grant

• Current Assignee: Schott AG (Carl-Zeiss-Stiftung)
• Original Assignee: Schott AG (Carl-Zeiss-Stiftung)
• Inventors: Wolfinger, Matthias, Gabel, Falk, Siebers, Friedrich, Weiss, Evelin, Bockmeyer, Matthias, Hochrein, Oliver
• Primary Examiner(s): Group, Karl E
• Application Number:
  US16/228,906
• Publication Number:
  US 20190194062A1
• Time in Patent Office: 935 Days
• CPC Class Codes: C03B 23/0305 Press-bending accelerated by applying mechanical forces, e.g. inertia, weights or local forces
• CPC Class Codes: C03B 27/012 by heat treatment, e.g. for crystallisation; Heat treatment of glass products before tempering by cooling C03B27/008, C03B27/016 take precedence
• CPC Class Codes: C03B 32/02 Thermal crystallisation, e.g. for crystallising glass bodies into glass-ceramic articles C03B27/012 takes precedence
• CPC Class Codes: C03C 1/002 Use of waste materials, e.g. slags
• CPC Class Codes: C03C 10/00 Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition
• CPC Class Codes: C03C 10/0027 containing SiO2, Al2O3, Li2O as main constituents
• CPC Class Codes: C03C 3/083 containing aluminium oxide or an iron compound
• CPC Class Codes: C03C 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 3/097 containing phosphorus, niobium or tantalum
• CPC Class Codes: C03C 4/10 for infrared transmitting glass
• CPC Class Codes: F24C 15/10 Tops, e.g. hot plates; Rings cover lids or splash guards F24C15/12; spillage trays or grooves F24C15/14
• CPC Class Codes: H05B 3/74 Non-metallic plates , e.g. vitroceramic, ceramic or glassceramic hobs, also including power or control circuits

Abstract

A sightglass for a stove is provided that has a substrate made of transparent coloured lithium aluminium silicate glass ceramic. The sightglass has a light transmittance of 0.1% to 50%. Standard illuminant D65 light, after passing through the glass ceramic, at a thickness of 4 mm, has a colour locus in the white region W1 determined by the following coordinates in the chromaticity diagram CIExyY-2°:

White region W1 x y 0.27 0.21 0.22 0.25 0.32 0.37 0.45 0.45 0.47 0.34 0.36  0.29.

Claims

1. A sightglass for a stove, the sightglass comprising:

a substrate made of transparent colored lithium aluminum silicate glass ceramic, wherein, in the wavelength range of 380 nm to 780 nm, the glass ceramic has a light transmittance of 0.1% to 50% when illuminated with a D65 standard illuminant light according to the DIN EN 410 (2011) standard, and has, when illuminated with the D65 standard illuminant light, after passing through the glass ceramic, at a thickness of 4 mm, a color locus in a white region W1 determined by coordinates in a chromaticity diagram CIExyY-2°

;

2. The sightglass of claim 1, wherein the substrate comprises, as the coloring component, less than 0.2% by weight of Nd₂O₃.

4. The sightglass of claim 1, wherein the substrate has an SnO₂ content of 0.05-0.8% by weight.

5. The sightglass of claim 1, wherein the substrate has an infrared transmission of 45-85% at a wavelength of 1600 nm.

6. The sightglass of claim 1, wherein the sightglass comprises in % by weight based on oxide:

Li₂O 2-5.5;

Al₂O₃ 16-26;

SiO₂ 58-72; and

MoO₃ 0.003-0.5.

7. The sightglass of claim 1, further comprising high quartz mixed crystals as a main crystal phase.

8. The sightglass of claim 1, wherein the substrate is configured as a stove sightglass and has a thickness of 2 to 8 mm.

9. The sightglass of claim 1, wherein the substrate is configured as a baking oven sightglass and has a thickness of 2 to 8 mm.

10. The sightglass of claim 1, wherein the substrate is configured as a barbecue sightglass and has a thickness of 2 to 8 mm.

11. The sightglass of claim 1, wherein the substrate comprises less than 0.01% by weight of V₂O₅.

12. The sightglass of claim 1, wherein the light transmittance of the glass ceramic is 0.1% to 10%.

13. The sightglass of claim 1, wherein the light transmittance of the glass ceramic is 2% to 6%.

14. The sightglass of claim 1, wherein the substrate comprises MoO₃ and V₂O₅ as coloring components in a relationship (in % by weight) of MoO₃/V₂O₅ that is greater than 1.

15. The sightglass of claim 14, wherein the relationship of MoO₃/V₂O₅ is greater than 3.

16. The sightglass of claim 14, wherein the relationship of MoO₃/V₂O₅ is greater than 5.

17. The sightglass of claim 14, wherein the relationship of MoO₃/V₂O₅ is greater than 10.

3. A sightglass for a stove, the sightglass comprising:

a substrate made of transparent coloring lithium aluminum silicate glass ceramic, wherein, in the wavelength range of 380 nm to 780 nm, the glass ceramic has a light transmittance of 0.1% to 50% when illuminated with a D65 standard illuminant light according to the DIN EN 410 (2011) standard, and has, when illuminated with the standard illuminant D65 light, after passing through the glass ceramic, at a thickness of 4 mm, a color locus in a white region W1 determined by coordinates in a chromaticity diagram CIExyY-2°

;

18. A sightglass for a stove, the sightglass comprising:

a substrate made of transparent coloring lithium aluminum silicate glass ceramic,

wherein, in the wavelength range of 380 nm to 780 nm, the glass ceramic has a light transmittance of 0.1% to 50% when illuminated with a D65 standard illuminant light according to the DIN EN 410 (2011) standard, and that prevents viewing into the stove when the stove is not in operation and has, when illuminated with the standard illuminant D65 light, after passing through the glass ceramic, at a thickness of 4 mm, a color locus in a white region W1 determined by coordinates in a chromaticity diagram CIExyY-2°

;