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US 11,453,609 B2Granted
Method for producing a glass article
AssigneeSchott AG
InventorsMalte Grimm, Christof Kass, Peter Nass
Life of this patent
Estimating the term…
Abstract
A method for producing a glass article having high hydrolytic resistance is provided. A glass tube consisting of borosilicate glass and having an Al2O3 content of less than 1 weight-%, a ZrO2 content of 2-12 weight-%, and a glass transition temperature Tg is reshaped into a glass article and is subsequently subjected to a thermal post-treatment. To reduce the alkali release of the glass article, the glass article is subjected to a treatment temperature of TB≥Tg+5° K over a treatment time of tB≥5 min and is subsequently cooled during the thermal post-treatment.
Claims15
A glass article, consisting of:
- a thermally treated borosilicate glass having an Al2O3 content of less than 1 weight-% and a ZrO2 content of 2-12 weight-%, the glass article having an alkali release of A≤0.5 mg/l Na2O equivalency according to ISO 4802 or an alkali release A≤3 mg/l Na2O equivalency according to USP 660 (glass grains) or ISO 720 (glass grains), wherein the glass of the glass article has a glass transition temperature Tg, wherein the glass article is thermally treated by subjecting the glass article to a treatment temperature of TB≥Tg+5° K over a treatment time of tb≥5 min and subsequently cooling the glass article.
Dependencies are inferred from the claim text.