Thin glass roll and method for producing same

A thin glass roll, comprising:

• a thin glass ribbon having a length of at least 10 meters and a thickness of at most 200 micrometers, the thin glass ribbon being wound with an inner radius in a range from:
• R
• min
• =
• 〈
• R
• 〉
• ·
• {
• [
• 0.7
• +
• exp
• ⁡
• (
• s
• 〈
• R
• 〉
• ·
• 0.053
• -
• 2.3
• )
• ]
• ·
• (
• 2
• -
• e
• -
• t
• )
• }
• ⁢
• ⁢
• to
• R
• max
• =
• 〈
• R
• 〉
• ·
• {
• [
• 3.4
• +
• exp
• ⁡
• (
• s
• 〈
• R
• 〉
• ·
• 0.05
• -
• 2.1
• )
• ]
• ·
• (
• 2
• -
• e
• -
• t
• )
• }
• wherein <R>is a mean value and
• s
• =
• 1
• N
• -
• 1
• ⁢
• ∑
• R
• i
• 2
• -
• 〈
• R
• 〉
• 2
• is a variance of a bending radii at break of a plurality N of samples made of the same glass material having the same thickness and the same glass edge quality as the glass material of the thin glass ribbon, wherein Ri are the bending radii at which the respective samples break, t is a minimum time period, in days, the thin glass roll withstands without break, and wherein at least twenty samples of the thin glass are subjected to a bending stress until break, in order to determine the mean value <R>of the bending radii Ri and the variance thereof,
• wherein the thin glass ribbon has two opposite faces and two opposite longitudinal edges, wherein the thin glass ribbon is wound so that a convexly curved face is that face for which samples cut out of the thin glass ribbon along the longitudinal edges and bent around the longitudinal edges in a common direction as the thin glass ribbon exhibits a smaller value of
• R
• min
• =
• 〈
• R
• 〉
• ·
• [
• 0.7
• +
• exp
• ⁢
• (
• s
• 〈
• R
• 〉
• ·
• 0.053
• -
• 2.3
• )
• ]
• compared to samples bent in an opposite direction, wherein <R>is the mean value and
• s
• =
• 1
• N
• -
• 1
• ⁢
• ∑
• R
• i
• 2
• -
• 〈
• R
• 〉
• 2
• is the variance of the bending radii at break of the samples, wherein Ri are the bending radii at which the respective samples break, and wherein at least twenty samples of the thin glass are subjected to a bending stress until break, in order to determine the mean value <R>of the bending radii Ri and the variance thereof.