Method of making glass including surface treatment with aluminum chloride at or just prior to annealing LEHR
This invention relates to a method of making glass. In certain example embodiments, a major surface(s) of the glass is treated with aluminum chloride (e.g., AlCl 3 ) at or just prior to the annealing lehr. The aluminum chloride treatment at or just prior to the annealing lehr, in either a float or patterned line glass making process, is advantageous in that it allows the treatment to be performed at a desirable glass temperature and permits exhaust functions in or proximate the annealing lehr to remove byproducts of the treatment in an efficient manner. In certain example embodiments, the glass may be polished for thinning after the treatment, with the polishing being performed on a major surface of the glass opposite to a major surface which has been treated with aluminum chloride.
1. A method of making soda-lime-silica based glass, the method comprising:
providing glass raw materials including sodium, silica, and calcium in a furnace to form a glass melt;
pre-annealing a glass strip formed from the glass melt at a temperature of 500-550 degrees C. in order to alter its coefficient of thermal expansion (CTE);
forwarding the pre-annealed glass strip to an annealing lehr where the glass strip is annealed; and
treating at least a first major surface of the pre-annealed glass strip with aluminum chloride, at or just prior to the annealing lehr, when the glass strip is at a temperature(s) of from about 580 degrees C. to 850 degrees C., in order to make the soda-lime-silica based glass from the pre-annealed glass strip, the annealing lehr supporting an environment having an excess of oxygen.
2. The method of claim 1 , wherein said treating comprises applying a mixture of aluminum chloride and at least one solvent to the surface of the glass strip, wherein a weight ratio of solvent to aluminum chloride in the mixture is from about 1:8 to 1:40.
3. The method of claim 1 , wherein said treating comprises applying a mixture of aluminum chloride and at least one solvent to the surface of the glass strip, wherein a weight ratio of solvent to aluminum chloride in the mixture is from about 1:10 to 1:20.
4. The method of claim 1 , wherein said treating comprises applying a mixture of AlCl 3 and at least one solvent to the surface of the glass strip, wherein the mixture is from about 1-25% AlCl 3 .
5. The method of claim 4 , wherein the solvent comprises one or more of methanol, ethanol, and isopropyl alcohol.
6. The method of claim 1 , wherein said treating comprises applying a mixture of AlCl 3 and at least one solvent to the surface of the glass strip, wherein the mixture is from about 2-20% AlCl 3 .
7. The method of claim 1 , wherein said treating comprises applying a mixture of AlCl 3 and at least one solvent to the surface of the glass strip, wherein the mixture is from about 3-15% AlCl 3 .
8. The method of claim 1 , further comprising: after said treating of the first major surface, polishing down a second major surface of the glass opposite to the first major surface that was subjected to said treating, in order to reduce a thickness of the glass for use in display applications.
9. The method of claim 8 , wherein said polishing comprises thinning down a glass substrate from a starting thickness of from about 1.3 to 1.8 mm to a finished thickness of from about 0.6-1.2 mm.