Verfahren zur Herstellung eines hohlen Glasformkörpers

Verfahren zur Herstellung eines hohlen Glasformkörpers, mit den folgenden Schritten:(a) Bereitstellen eines hohlen Glasrohlings aus Borosilikatglas;(b) Umformen des Glasrohlings zu einem Glasformkörper;(b1) Waschen des im Schritt (b) aus dem Glasrohling erhaltenen Glasformkörpers vor dem Schritt (c);(c) Flüssigbeschichten der Innenoberfläche des Glasformkörpers mit einer Schutzschicht mittels eines Sol-Gel-Verfahrens, die gegenüber dem Material des Glasrohlings eine erhöhte Beständigkeit gegen einen chemischen Angriff aufweist;(c1) Aushärten der Schutzschicht bei erhöhter Temperatur, wobei die offene Porosität der Schutzschicht nach der Aushärtung kleiner als 5 % ist und(d) Kühlen des Glasformkörpers zur Reduzierung von Spannungen. The method comprises providing a hollow glass preform, transforming the glass preform to a glass mold body, washing the glass preform with deionized water in increased temperature, coating the interior surface of the glass mold body with a protective layer that has an increased consistency against a chemical etching against the material of the glass preform, cooling the glass mold body for reducing tension and washing the glass mold body with deionized water in increased temperature. The coating is carried out by a liquid coating. The method comprises providing a hollow glass preform, transforming the glass preform to a glass mold body, washing the glass preform with deionized water in elevated temperature, coating the interior surface of the glass mold body with a protective layer having an increased consistency against a chemical etching against the material of the glass preform, cooling the glass mold body for reducing tension and washing the glass mold body with deionized water in elevated temperature. The coating is carried out by a liquid coating and is applied by immersing, spraying, flooding or pouring. The coating is produced by decomposition of a silicon layer that glazes at 300[deg] C. The coating is applied by a sol-gel-process and is crosslinked or hardened after the application on the interior surface of the glass mold body at elevated temperatures. The coating is hardened during cooling of the glass mold body. The cooling of the glass mold body is carried out at T10 1>3>-100 K to T10 1>3>+100 K, where T10 1>3>is a glass temperature in which the glass has a viscosity of 10 1>3>. The transformation of the glass preform is carried out at 1100[deg] C. The protective layer consists of zirconium oxide or a mixed oxide o