A quartz glass crucible (1) has a structure wherein a peak of a distribution of a total concentration of Na, K, and Ca in a depth direction from an inner surface (10i) of the crucible is present at a position deeper than the inner surface (10i). In an exemplary embodiment, the quartz glass crucible is capable of improving the yield of a silicon single crystal by suppressing peeling-off of brown rings.

An optical fiber manufacturing method includes: a drawing step of heating one end portion of an optical fiber preform to melt and deform the one end portion and drawing an optical fiber, wherein in the drawing step, drawing is performed while applying pressure to a melted-deformed portion that is melted and deformed.

The present invention relates to a silica glass including bublles in the number of 1×10.sup.7/cm.sup.3 to 1×10.sup.15/cm.sup.3 and having a density of 0.5 g/cm.sup.3 to 1.95 g/cm.sup.3. The present invention also relates to a method for producing a silica glass, including: a step of depositing SiO.sub.2 fine particles generated by flame hydrolysis of a silicon compound, to obtain a silica glass porous body; a step of heating and sintering the silica glass porous body in an inert gas atmosphere, to obtain a silica glass dense body; and a step of performing a foaming treatment to heat the silica glass dense body under a reduced pressure condition.

A glass composition includes: 50 mol % to 69 mol % SiO.sub.2; 12.5 mol % to 25 mol % Al.sub.2O.sub.3; 0 mol % to 8 mol % B.sub.2O.sub.3; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na.sub.2O; 0 mol % to 2.5 mol % La.sub.2O.sub.3; and greater than 8 mol % to 18 mol % Li.sub.2O, wherein (Li.sub.2O+Na.sub.2O+MgO)/Al.sub.2O.sub.3 is from 0.9 to less than 1.3; and Al.sub.2O.sub.3+MgO+Li.sub.2O+ZrO.sub.2+La.sub.2O.sub.3+Y.sub.2O.sub.3 is from greater than 23 mol % to less than 50 mol %. The glass composition may be characterized by at least one of the following: a K.sub.1C value measured by a chevron short bar method of at least 0.75; and a K.sub.1C value measured by a double torsion method of at least 0.8. The glass composition is chemically strengthenable. The glass composition may be used in a glass article or a consumer electronic product.

The disclosure relates to highly temperable colored glass compositions. The colored glass compositions have high coefficients of thermal expansion and high Young's moduli that advantageously absorb in the ultraviolet and/or blue wavelength ranges. Methods of making such glasses are also provided.

One aspect relates to a process for the preparation of a quartz glass body. The process includes providing silicon dioxide particles, making a glass melt out of the silicon dioxide particles in an oven and making a quartz glass body out of at least part of the glass melt. The oven has a gas outlet through which gas is removed from the oven, wherein the dew point of the gas on exiting the oven through the gas outlet is less than 0° C. One aspect further relates to a quartz glass body which is obtainable by this process. One aspect further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

The disclosure relates to highly temperable colored glass compositions. The colored glass compositions have high coefficients of thermal expansion and high Young's moduli that advantageously absorb in the ultraviolet and/or blue wavelength ranges. Methods of making such glasses are also provided.

A glass composition includes: 50 mol % to 69 mol % SiO.sub.2; 12.5 mol % to 25 mol % Al.sub.2O.sub.3; 0 mol % to 8 mol % B.sub.2O.sub.3; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na.sub.2O; 0 mol % to 2.5 mol % La.sub.2O.sub.3; and greater than 8 mol % to 18 mol % Li.sub.2O, wherein (Li.sub.2O+Na.sub.2O+MgO)/Al.sub.2O.sub.3 is from 0.9 to less than 1.3; and Al.sub.2O.sub.3+MgO+Li.sub.2O+ZrO.sub.2+La.sub.2O.sub.3+Y.sub.2O.sub.3 is from greater than 23 mol % to less than 50 mol %. The glass composition may be characterized by at least one of the following: a K.sub.1C value measured by a chevron short bar method of at least 0.75; and a K.sub.1C value measured by a double torsion method of at least 0.8. The glass composition is chemically strengthenable. The glass composition may be used in a glass article or a consumer electronic product.

A glass includes the following components in the specified proportions (in % by weight): 50-80% SiO.sub.2, 2-30% B.sub.2O.sub.3, 0-5% Al.sub.2O.sub.3, 0-10% CaO, 0-10% BaO, 0-5% Li.sub.2O, 0-20% Na.sub.2O, 1-25% K.sub.2O, and 5-30% ΣR.sub.2O. R.sub.2O includes at least one alkali metal oxide. The glass includes at least one first solarization component and at least one second solarization component. A proportion of the first solarization component in the glass is in a range from 0.01 to <1.0 ppm (by weight) and a proportion of the second solarization component in the glass is in a range from 1000 to 10,000 ppm (by weight).

Ion-exchanged alkali aluminosilicate glass articles with a ratio of peak compressive stress value to Young's modulus value of 15 or more. The glass articles may include Al.sub.2O.sub.3 mol %+RO mol %≥17 mol %, where RO mol %=MgO mol %+CaO mol %, and be substantially free of ZnO, SrO, BaO, B.sub.2O.sub.3, P.sub.2O.sub.5, Li.sub.2O, and K.sub.2O. The glass articles may have a peak compressive stress value in a range of 500 MPa to 1300 MPa. The glass articles are suitable for various high-strength applications, including cover glass applications that experience significant bending stresses during use, for example, cover glasses for flexible displays.