Method and apparatus for the hot forming of glass workpieces, and hot-formed glass container
A hollow glass article is a container or part of a vessel having a neck or shoulder region and a wall. The glass article encompasses the wall and the neck or shoulder region of the container. The wall has a round or oval cross section and the container has a characteristic surface region on an outer glass surface of the hollow glass article. The following applies for a ratio between a mean tangential gradient value and a mean axial gradient value in the characteristic surface region: mean tangential gradient value/mean axial gradient value <0.6.
1 . A hollow glass article, wherein the glass article is a container or part of a vessel having a neck or shoulder region and a wall, wherein the glass article encompasses the wall and the neck or shoulder region of the container, wherein the wall has a round or oval cross section and the container has a characteristic surface region on an outer glass surface of the hollow glass article, and wherein the following applies for a ratio between a mean tangential gradient value and a mean axial gradient value in the characteristic surface region: mean tangential gradient value/mean axial gradient value <0.6.
2 . The hollow glass article of claim 1 , wherein the following applies for the ratio between the mean tangential gradient value and the mean axial gradient value in the characteristic surface region: mean tangential gradient value/mean axial gradient value <0.45.
3 . The hollow glass article of claim 1 , wherein a height profile in the characteristic surface region exhibits anisotropy.
4 . The hollow glass article of claim 1 , wherein the characteristic region has portions with increased average roughness Rz axial measured parallel to a longitudinal axis of the glass article, and wherein the portions with increased average roughness Rz axial extend over an entire area of the characteristic region.
5 . The hollow glass article of claim 4 , wherein at least one portion with increased average roughness Rz axial has at least one encircling groove or score.
6 . The hollow glass article of claim 5 , wherein the at least one portion comprises a plurality of scores.
7 . The hollow glass article of claim 1 , wherein the characteristic surface region has portions with a roughness depth Rz axial measured parallel to a longitudinal axis of the glass article that is greater than the roughness depth Rz tangential measured at a height of the wall transversely.
8 . The hollow glass article of claim 7 , wherein at least one portion has at least one circumferential score or groove.
9 . The hollow glass article of claim 8 , wherein the at least one portion comprises a plurality of scores.
10 . The hollow glass article of claim 1 , wherein the glass article is a bottle, a vial, or a part of a carpule, and the characteristic region is formed by an outer surface of a rolled rim, or the glass article is a syringe and the characteristic region is formed by an outer surface of a cone.
11 . The hollow glass article of claim 1 , wherein the glass article has a tubular portion along its height.
12 . The hollow glass article of claim 11 , wherein the glass article has a wall thickness with a standard deviation of less than 0.05 mm in the tubular portion.
13 . The hollow glass article of claim 11 , wherein the characteristic surface region is located outside the tubular portion in an end region of the glass article.
14 . The hollow glass article of claim 13 , wherein a diameter of the glass article in the characteristic surface region is less than a diameter of the glass article in the tubular portion.
15 . The hollow glass article of claim 1 , wherein the hollow glass article comprises a borosilicate glass.