US2020010358A1PendingUtilityA1
Glasses having improved ion exchangeability and thermal expansion
Est. expiryFeb 8, 2037(~10.5 yrs left)· nominal 20-yr term from priority
Inventors:Ulrich FotheringhamMichael SchwallUlrich PeuchertMiriam KunzeMartun HovhannisyanHolger Wegener
C03C 4/00C03C 3/04C03B 23/0006C03C 3/093C03C 10/0054C03C 2203/10C03C 3/091C03C 2203/50C03B 17/06
67
PatentIndex Score
0
Cited by
0
References
0
Claims
Abstract
The present invention relates to glasses having a composition made up of base glasses. The glasses have a good chemical toughenability in combination with an advantageous coefficient of thermal expansion. Owing to their composition and the production process, the homogeneity of the properties of the glasses at their surface is high compared to the bulk glass. Furthermore, the fragility of the glasses is low, so that they can be processed to produce very thin glass articles.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1 . A glass, comprising:
A constituent phase
min.
max.
Albite
10 mol %
40 mol %
Reedmergnerite
10 mol %
65 mol %
Potassium reedmergnerite
0 mol %
20 mol %
Grossular
0 mol %
10 mol %
Cordierite
0 mol %
10 mol %
Willemite
0 mol %
15 mol %
Silicon dioxide
0 mol %
50 mol %
Diboron trioxide
0 mol %
15 mol %
Titanium wadeite
0 mol %
24 mol %
Strontium feldspar
0 mol %
20 mol %
Celsian
0 mol %
20 mol %
wherein a number of degrees of angular freedom per atom is calculated according to a formula:
f
=
∑
i
=
1
n
c
i
·
z
i
·
f
i
∑
i
=
1
n
c
i
·
z
i
,
(
1
)
wherein f is a number of degrees of angular freedom per atom, c i is a mole fraction of the i-th constituent phase, z i is a number of atoms per structural unit in the i-th constituent phase, f i is a number of degrees of angular freedom per atom in the i-th constituent phase, and “n” is a number of constituent phases, such that said number of degrees of angular freedom per atom is not more than 0.24.
2 . The glass according to claim 1 , wherein said glass has an average thickness of not more than 2 mm.
3 . The glass according to claim 1 , wherein said glass has a composition which includes the following constituent phases:
Constituent phase
min.
max.
Albite
15 mol %
40 mol %
Reedmergnerite
10 mol %
40 mol %
Potassium
1 mol %
15 mol %
reedmergnerite
Grossular
0 mol %
9 mol %
Cordierite
0 mol %
8.5 mol %
Willemite
0 mol %
8.5 mol %
Silicon dioxide
1 mol %
40 mol %
Diboron trioxide
1 mol %
15 mol %
Titanium wadeite
0 mol %
20 mol %
Strontium feldspar
0 mol %
10 mol %
Cel sian
0 mol %
10 mol %
4 . The glass according to claim 1 , wherein said glass has a composition which includes the following constituent phases:
Constituent phase
min.
max.
Albite
20 mol %
40 mol %
Reedmergnerite
10 mol %
35 mol %
Potassium
1 mol %
15 mol %
reedmergnerite
Grossular
0 mol %
8.5 mol %
Cordierite
0 mol %
8.5 mol %
Willemite
0 mol %
7.5 mol %
Silicon dioxide
3 mol %
40 mol %
Diboron trioxide
1 mol %
12 mol %
Titanium wadeite
0 mol %
18 mol %
Strontium feldspar
0 mol %
5 mol %
Celsian
0 mol %
5 mol %
5 . The glass according to claim 1 , wherein the glass is free of grossular, willemite, strontium feldspar and/or celsian.
6 . The glass according to claim 1 , wherein a sum of the proportions of silicon dioxide and diboron trioxide is not more than 50 mol %.
7 . The glass according to claim 1 , wherein the glass further includes a balance of further constituents which does not exceed a proportion of 5 mol %, and said balance does not contain the following oxides: SiO 2 , TiO 2 , B 2 O 3 , Al 2 O 3 , ZnO, MgO, CaO, BaO, SrO, Na 2 O and K 2 O.
8 . The glass according to claim 7 , wherein said proportion of said balance is not more than 2 mol % of said glass.
9 . The glass according to claim 1 , wherein a proportion of potassium reedmergnerite is not more than 15 mol %.
10 . The glass according to claim 1 , wherein a coefficient of thermal expansion is calculated according to formulae:
E
pot
_
=
∑
i
=
1
n
c
i
·
∑
j
=
1
m
z
i
,
j
·
E
pot
,
j
∑
i
=
1
n
c
i
·
∑
j
=
1
m
z
i
,
j
,
(
2
)
wherein E pot is an average potential well depth, m is a number of cation types present, E pot,j is a potential well depth for a j-th cation type, and z j,i is a number of cations of the j-th type in an i-th constituent phase; and
CTE
=
(
51815
(
kJ
Mol
)
E
pot
_
-
27.205
)
ppm
/
K
,
(
3
)
wherein CTE is the thermal coefficient of thermal expansion, such that said coefficient of thermal expansion is between 4.5 ppm/K and 6.5 ppm/K.
11 . The glass according to claim 10 , wherein the coefficient of thermal expansion calculated according to formulae (2) and (3) in a surface glass corresponds to at least 50% of the coefficient of thermal expansion calculated according to formulae (2) and (3) in a bulk glass.
12 . The glass according to claim 10 , wherein the coefficient of thermal expansion calculated according to formulae (2) and (3) in a surface glass corresponds to not more than 99% of the coefficient of thermal expansion calculated according to formulae (2) and (3) in a bulk glass.
13 . A method for producing a glass, comprising the steps of:
melting a plurality of glass raw materials to produce a glass melt having a composition which includes:
A constituent phase
min.
max.
Albite
10 mol %
40 mol %
Reedmergnerite
10 mol %
65 mol %
Potassium reedmergnerite
0 mol %
20 mol %
Grossular
0 mol %
10 mol %
Cordierite
0 mol %
10 mol %
Willemite
0 mol %
15 mol %
Silicon dioxide
0 mol %
50 mol %
Diboron trioxide
0 mol %
15 mol %
Titanium wadeite
0 mol %
24 mol %
Strontium feldspar
0 mol %
20 mol %
Celsian
0 mol %
20 mol %
wherein a number of degrees of angular freedom per atom is calculated according to a formula:
f
=
∑
i
=
1
n
c
i
·
z
i
·
f
i
∑
i
=
1
n
c
i
·
z
i
,
(
1
)
wherein f is a number of degrees of angular freedom per atom, c i is a mole fraction of the i-th constituent phase, z i is a number of atoms per structural unit in the i-th constituent phase, f i is a number of degrees of angular freedom per atom in the i-th constituent phase, and “n” is a number of constituent phases, such that said number of degrees of angular freedom per atom is not more than 0.24;
moulding a flat glass article from the glass melt; and
cooling the flat glass article.
14 . The method according to claim 13 , wherein the moulding of the flat glass article is carried out in one of a down draw, an overflow fusion, and a redrawing process.
15 . The method according to claim 13 , wherein the step of cooling is carried out by an active cooling step using a coolant or by allowing the flat glass article to cool passively.
16 . A method, comprising the steps of:
providing a glass having a composition including:
A constituent phase
min.
max.
Albite
10 mol %
40 mol %
Reedmergnerite
10 mol %
65 mol %
Potassium reedmergnerite
0 mol %
20 mol %
Grossular
0 mol %
10 mol %
Cordierite
0 mol %
10 mol %
Willemite
0 mol %
15 mol %
Silicon dioxide
0 mol %
50 mol %
Diboron trioxide
0 mol %
15 mol %
Titanium wadeite
0 mol %
24 mol %
Strontium feldspar
0 mol %
20 mol %
Celsian
0 mol %
20 mol %
wherein a number of degrees of angular freedom per atom is calculated according to a formula:
f
=
∑
i
=
1
n
c
i
·
z
i
·
f
i
∑
i
=
1
n
c
i
·
z
i
,
(
1
)
wherein f is a number of degrees of angular freedom per atom, c i is a mole fraction of the i-th constituent phase, z i is a number of atoms per structural unit in the i-th constituent phase, f i is a number of degrees of angular freedom per atom in the i-th constituent phase, and “n” is a number of constituent phases, such that said number of degrees of angular freedom per atom is not more than 0.24;
using said glass as one of a covering glass, a display glass, a substrate glass, an electrically insulating dielectric intermediate layer, and a polymer replacement in a finishing of surfaces.Join the waitlist — get patent alerts
Track US2020010358A1 — get alerts on status changes and closely related new filings.
We store only your email — no account needed. See our privacy policy.