US 11,718,556 B2
Glass for chemical strengthening, chemically strengthened glass, and electronic device case
Qing Li, Tokyo (JP); Akio Koike, Tokyo (JP); and Eriko Maeda, Tokyo (JP)
Assigned to AGC Inc., Chiyoda-ku (JP)
Filed by AGC Inc., Chiyoda-ku (JP)
Filed on Jan. 21, 2020, as Appl. No. 16/747,584.
Application 16/747,584 is a continuation of application No. PCT/JP2018/027577, filed on Jul. 23, 2018.
Claims priority of application No. 2017-144868 (JP), filed on Jul. 26, 2017; application No. 2018-002200 (JP), filed on Jan. 10, 2018; and application No. 2018-006451 (JP), filed on Jan. 18, 2018.
Prior Publication US 2020/0156994 A1, May 21, 2020
Int. Cl. B32B 15/04 (2006.01); B32B 17/06 (2006.01); C03C 21/00 (2006.01); C03C 3/083 (2006.01); C03C 4/00 (2006.01); C03C 10/00 (2006.01)
CPC C03C 21/002 (2013.01) [C03C 3/083 (2013.01); C03C 4/0028 (2013.01); C03C 10/0027 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A glass for chemical strengthening, comprising a lithium aluminosilicate crystallized glass, and comprising, as expressed by mass % on an oxide basis:
58 to 71% of SiO2;
8 to 30% of Al2O3;
1 to 15% of Li2O;
1 to 5% of Na2O;
0 to 2% of K2O;
0 to 6% of SnO2;
0 to 8% of ZrO2;
0 to 6% of P2O5;
0 to 1% of BaO; and
0 to 2% of ZnO,
a total of SnO2 and ZrO2 being 4 to 12%,
wherein the glass for chemical strengthening is free of As2O3 and Sb2O3, and
the glass for chemical strengthening has:
an average transmittance at a wavelength of 380 to 780 nm of 70% or higher in terms of a thickness of 0.8 mm;
a haze value of 0.7% or lower in terms of the thickness of 0.8 mm at a C illuminant;
a Young's modulus of 85 GPa or more;
a fracture toughness value of 0.90 MPa·m1/2 or more; and
a thermal conductivity at 20° C. of 1.3 W/m·K or more.