	US 12,202,768 B2
	Photochromic glass and photochromic glass windows
Timothy James Kiczenski, Corning, NY (US); and Nadja Teresia Lönnroth, Helsinki (FI)
Assigned to CORNING INCORPORATED, Corning, NY (US)
Appl. No. 17/423,169
Filed by CORNING INCORPORATED, Corning, NY (US)
PCT Filed Jan. 13, 2020, PCT No. PCT/US2020/013275 § 371(c)(1), (2) Date Jul. 15, 2021, PCT Pub. No. WO2020/150120, PCT Pub. Date Jul. 23, 2020.
Claims priority of provisional application 62/794,238, filed on Jan. 18, 2019.
Prior Publication US 2022/0127184 A1, Apr. 28, 2022
Int. Cl. C03C 4/06 (2006.01); C03C 3/097 (2006.01); C03C 3/11 (2006.01)

CPC C03C 4/06 (2013.01) [C03C 3/11 (2013.01)]

33 Claims

1. A photochromic glass, comprising:

(i) a glass matrix that, comprising in mol percent (mol %) based on oxides:

66 mol %≤SiO₂≤75 mol %;

8 mol %≤B₂O₃≤13 mol %;

3.5 mol %≤Al₂O₃≤7 mol %;

1.5 mol %≤P₂O₅≤6 mol %,

3.6 mol %≤Na₂O≤5.5 mol %;

3 mol %≤K₂O≤9.5 mol %;

0 mol %≤MgO≤4 mol %;

0 mol %≤Li₂O≤0.05 mol %; 0 mol %≤BaO≤0.05 mol %; 0 mol %≤CaO ≤0.05 mole %; wherein the amount of (Li₂O+BaO+CaO≤0.1 mole %);

and

(ii) a plurality of photochromic agents, comprising in mol percent (%) with respect to the glass matrix:

0.07%≤Ag≤0.15%;

0.14%≤Cl≤0.25%;

0.025%≤Br≤0.04%;

0.0065%≤CuO≤0.015%, and

wherein CuO/Ag≤0.22.