Glass raw material granules and method for their production

Patent metadata

Field	Value
Publication number	US-2018354841-A1
Application number	US-201816103296-A
Country	US
Kind code	A1
Filing date	Aug 14, 2018
Priority date	Feb 26, 2016
Publication date	Dec 13, 2018
Grant date	—

Abstract

To provide high-strength granules having a broad range of applications of the glass composition, and a method for their production. The method for producing glass raw material granules comprises mixing and granulating a glass raw material composition with water, wherein the glass raw material composition contains at least silica and an aluminum source, and the aluminum source contains hydraulic alumina.

First claim

What is claimed is:

1 . A method for producing glass raw material granules, comprising mixing and granulating a glass raw material composition with water, wherein the glass raw material composition comprises at least silica and an aluminum source, and the aluminum source contains hydraulic alumina.

2 . The method for producing glass raw material granules according to claim 1 , wherein the content of the hydraulic alumina is from 2 to 30 mass % to the solid content of the glass raw material composition.

3 . The method for producing glass raw material granules according to claim 1 , wherein the content of the hydraulic alumina is at least 25 mass % as calculated as Al 2 O 3 , to the aluminum source.

4 . The method for producing glass raw material granules according to claim 1 , wherein the glass raw material composition contains silica in such an amount that based on oxides of glass obtainable from the granules, the content of SiO 2 corresponds to from 40 to 75 mass %.

5 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the content of Al 2 O 3 is from 3 to 30 mass %.

6 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the total content of Li 2 O, Na 2 O and K 2 O is less than 5 mass %.

7 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the total content of Li 2 O, Na 2 O and K 2 O is from 5 to 20 mass %.

8 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the content of CaO is at most 30 mass %.

9 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the total content of SrO and BaO is at most 40 mass %.

10 . The method for producing glass raw material granules according to claim 1 , wherein in the composition based on oxides of glass obtainable from the granules, the total content of CaO, SrO and BaO is at most 45 mass %.

11 . A method for producing a glass article, comprising a glass melting step of heating glass raw material granules obtainable by the method for producing glass raw material granules as defined in claim 1 to obtain molten glass, a molding step of molding the obtained molten glass, and an annealing step of annealing the glass after the molding.

12 . Glass raw material granules being granules to be used for producing glass, which comprise at least silica and an aluminum source and which have peaks from 0 to 25 ppm and from 60 to 85 ppm in the 27 Al MAS NMR spectrum, wherein the ratio of the height y of the peak of from 60 to 85 ppm to the height x of the peak of from 0 to 25 ppm (y/x) is at least 0.04.

13 . A method for producing molten glass, comprising a glass melting step of heating the glass raw material granules as defined in claim 12 to obtain molten glass.

14 . A method for producing a glass article using the production method for molten glass as defined in claim 13 , which comprises said glass melting step, a molding step of molding the obtained molten glass, and an annealing step of annealing the glass after the molding.

Assignees

• Agc Inc

Inventors

• Kunisa Yasuhiro
• Miyazaki Seiji
• Shinohara Nobuhiro
• Miyajima Tatsuya

Classifications

• C03C1/026

  Pelletisation or prereacting of powdered raw materials (apparatus or methods C03B1/02) · CPC title

• C03B1/02 Primary

  Compacting the glass batches, e.g. pelletising · CPC title

• C03B11/00

  Pressing {molten} glass {or performed glass reheated to equivalent low viscosity without blowing (shaping molten glass by a press-blow process C03B9/00, e.g. C03B9/193; re-forming shaped glass C03B23/00; re-heating the performed glass C03B29/00; transporting the performed or pressed glass during its manufacture C03B35/00)} · CPC title

• C03C3/087

  containing calcium oxide, e.g. common sheet or container glass · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title