公开(公告)号：US20210147290A1

公开(公告)日：2021-05-20

申请号：US17160468

申请日：2021-01-28

Applicant: AGC Inc.

Inventor： Hirofumi TOKUNAGA ,  Daisuke KOBAYASHI ,  Kazutaka ONO ,  Atsuyoshi TAKENAKA ,  Yoshitaka MAEYANAGI

IPC: C03C21/00 ,  C03C19/00 ,  C03C17/00 ,  C03C3/087 ,  C03C3/091 ,  G02F1/1335

Abstract: The present invention relates to a glass substrate including a pair of main surfaces and an end surface, and having a surface layer diffusion Sn atom concentration of 2.0×1018 atomic/cm3 or more and 1.4×1019 atomic/cm3 or less in at least one of the main surfaces, the surface layer diffusion Sn atom concentration being obtained by subtracting an Sn atom concentration of an inside of the glass substrate from an Sn atom concentration of a surface layer of the glass substrate, in which the Sn atom concentration of a surface layer of the glass substrate is defined as an Sn atom concentration at a depth of 0.1 to 0.3 μm from the main surface and the Sn atom concentration of an inside of the glass substrate is defined as an Sn atom concentration at a depth of 9.0 to 9.2 μm from the main surface.

公开(公告)号：US20210024403A1

公开(公告)日：2021-01-28

申请号：US17070035

申请日：2020-10-14

Applicant: AGC Inc.

Inventor： Hirofumi TOKUNAGA ,  Kazutaka ONO ,  Motoyuki HIROSE

IPC: C03C3/087 ,  C03B17/06 ,  C03C4/00

Abstract: An alkali-free glass has a strain point of 650° C. or more, an average coefficient of thermal expansion at 50 to 350° C. of from 30×10−7 to 45×10−7/° C., and a temperature T2 at which a glass viscosity reaches 102 dPa·s of from 1,500 to 1,800° C. The alkali-free glass contains, as represented by mol % based on oxides, SiO2: from 62 to 70%, Al2O3: from 9 to 16% B2O3: from 0 to 12%, MgO: from 3 to 10%, CaO: from 4 to 12%, SrO: from 0 to 6%, and Fe2O3: from 0.001 to 0.04%, provided that MgO+CaO+SrO+BaO is from 12 to 25%. The alkali-free glass has a β-OH value of from 0.35 to 0.85/mm.

公开(公告)号：US20190047899A1

公开(公告)日：2019-02-14

申请号：US16161220

申请日：2018-10-16

Applicant: AGC Inc.

Inventor： Hirofumi TOKUNAGA ,  Kazutaka ONO

IPC: C03C3/091

Abstract: To provide an alkali-free glass having a high specific elastic modulus, a suitable strain point, a low density, a not too low thermal expansion coefficient, a good clarity and a good solubility.An alkali-free glass, which comprises, as represented by mol % based on oxides, SiO2: 62 to 70%, Al2O3: 11 to 14%, B2O3: 3 to 6%, MgO: 7 to 10%, CaO: 3 to 9%, SrO: 1 to 5% and BaO: 0 to 1%, wherein [SiO2]+0.7[Al2O3]+1.2[B2O3]+0.5[MgO]+0.4[CaO]−0.25[SrO]−0.88[BaO] is at least 85, [SiO2]+0.45[Al2O3]+0.21[B2O3]−0.042[MgO]+0.042[CaO]+0.15[SrO]+0.38[BaO] is from 72 to 75, 0.4[SiO2]+0.4[Al2O3]+0.25[B2O3]−0.7[MgO]−0.88[CaO]−1.4[SrO]−1.7[BaO] is at most 19, the specific modulus is at least 32 MN·m/kg, the strain point is from 690 to 710° C., the density is at most 2.54 g/cm3, the average thermal expansion coefficient at from 50 to 350° C. is at least 35×10−7/° C., and the temperature T2 at which the glass viscosity reaches 102 dPa·s is from 1,610 to 1,680° C.

公开(公告)号：US20250011217A1

公开(公告)日：2025-01-09

申请号：US18887267

申请日：2024-09-17

Applicant: AGC INC.

Inventor： Hirofumi TOKUNAGA ,  Kazutaka ONO

IPC: C03C3/087 ,  C03C3/091 ,  G11B5/73 ,  G11B7/2531

Abstract: A glass has a density of 2.60 g/cm3 or lower, a Young's modulus of 88 GPa or more, a strain point of 650 to 720° C., a temperature T4 at which a glass viscosity reaches 104 dPa·s of 1,320° C. or lower, a glass surface devitrification temperature (Tc) of T4+20° C. or lower, and an average coefficient of thermal expansion of 30×10−7 to 43×10−7/° C. at 50 to 350° C. The glass contains, as represented by mol % based on oxides, 50 to 80% of SiO2, 8 to 20% of Al2O3, 0 to 0.5% in total of at least one kind of alkali metal oxide selected from the group consisting of Li2O, Na2O and K2O, and 0 to 1% of P2O5.

公开(公告)号：US20210387897A1

公开(公告)日：2021-12-16

申请号：US17396247

申请日：2021-08-06

Applicant: AGC Inc.

Inventor： Hirofumi TOKUNAGA ,  Kazutaka ONO

IPC: C03C3/091 ,  C03C3/087

Abstract: An alkali-free glass includes, in mol % in terms of oxides: SiO2: 63-75%; Al2O3:10-16%; B2O3: larger than 0.5% and 5% or smaller; MgO: 0.1-15%; CaO: 0.1-12%; SrO: 0-8%; and BaO: 0-6%. [MgO]/[CaO] is larger than 1.5. A value of Formula (A) is 82.5 or larger. A value of Formula (B) is 690 or larger and 800 or smaller. A value of Formula (C) is 100 or smaller. A value of Formula (D) is 20 or smaller. The alkali-free glass has a Young's modulus of 83 GPa or larger and a surface devitrification viscosity ηc of 104.2 dPa·s or higher.

公开(公告)号：US20190185368A1

公开(公告)日：2019-06-20

申请号：US16282363

申请日：2019-02-22

Applicant: AGC Inc.

Inventor： Hirofumi TOKUNAGA ,  Kazutaka ONO ,  Motoyuki HIROSE

IPC: C03C3/093 ,  C03C3/087

CPC classification number: C03C3/093 ,  C03C3/087 ,  C03C3/091

Abstract: To provide an alkali-free glass, of which the compaction is low, the strain point is high, and the ultraviolet transmittance is high, and which is easy to melt.An alkali-free glass, which comprises, as represented by mol % based on oxides, SiO2from 65 to 75, Al2O3from 9 to 15, B2O3from 0 to 3, MgOfrom 0 to 12, CaOfrom 0 to 8, SrOfrom 0 to 6, and BaOfrom 0 to 5, wherein MgO+CaO+SrO+BaO is from 12 to 22, and 4.84[Fe2O3]+5.65[Na2O]+4.03[K2O]+4.55[SnO2] is at most 0.55, and of which the compaction is at most 80 ppm.