Embodiments disclosed therein generally pertain to selectively strengthening glass. More particularly, techniques are described for selectively strengthening cover glass, which tends to be thin, for electronic devices, namely, portable electronic devices.

Disclosed herein are laminated glass articles having a hard scratch resistant outer surface. In some embodiments, the laminated glass article includes a glass core layer and a glass clad layer. In some embodiments, the laminated glass article includes a glass core layer sandwiched between two glass clad layers. In some embodiments, the clad glass is selected from the group of consisting of: aluminate glasses; oxynitride glasses; rare earth/transition metal glasses; beryl glasses; and glasses containing lithium, zirconium, or both lithium and zirconium. Such glass compositions can thus be used in forming the clad layer.

A method of manufacturing a cell unit substrate, includes: a modified zone-formation step in which modified zones are formed along a predetermined cutting line on the mother substrate to be spaced apart from each other by a first distance by irradiating the mother substrate with laser beams having an energy intensity within an ablation threshold of the mother substrate along the cutting line, a modified zone-etching step in which through-holes are formed along the cutting line on the mother substrate to be spaced apart from each other by the first distance by etching the modified zones, a surface strengthening step in which the mother substrate having the through-holes therein is subjected to surface strengthening, with the mother substrate dipped in a strengthening solution, and a substrate separation step in which the cell unit substrates are separated from the surface-strengthened mother substrate.

A glass composition includes greater than or equal to 60 mol % to less than or equal to 66 mol % SiO.sub.2, greater than or equal to 14 mol % to less than or equal to 16 mol % Al.sub.2O.sub.3, greater than or equal to 7 mol % to less than or equal to 9 mol % Li.sub.2O, greater than or equal to 4 mol % to less than or equal to 6 mol % Na.sub.2O, greater than or equal to 0.5 mol % to less than or equal to 3 mol % P.sub.2O.sub.5, greater than or equal to 0.5 mol % to less than or equal to 6 mol % B.sub.2O.sub.3; and greater than 0 mol % to less than or equal to 1 mol % TiO.sub.2. The glass composition may have a fracture toughness of greater than or equal 0.75 MPa√m. A glass composition includes SiO.sub.2, Al.sub.2O.sub.3, Li.sub.2O, Na.sub.2O, P.sub.2O.sub.5, and B.sub.2O.sub.3, wherein a molar ratio of Li.sub.2O/Na.sub.2O is greater than or equal to 1.2 to less than or equal to 2.0, the glass has a liquidus viscosity in the range from greater than or equal to 50 kP to less than or equal to 75 kP, and the glass has a K.sub.IC fracture toughness greater than or equal to 0.75 MPa.Math.m.sup.0.5. The glass composition is chemically strengthenable. The glass composition may be used in a glass-based article or a consumer electronic product.

A method for hardening a transparent material includes the steps of introducing a material modification to the transparent material using a laser beam of ultrashort laser pulses of an ultrashort pulse laser so as to harden at least a portion of the transparent material.

Glass-based articles are provided that exhibit improved fracture resistance. The relationships between properties attributable to the glass composition and stress profile of the glass-based articles are provided that indicate improved fracture resistance.

A glass composition includes SiO.sub.2, Al.sub.2O.sub.3, optionally B.sub.2O.sub.3, optionally Li.sub.2O, Na.sub.2O, optionally K.sub.2O, optionally CaO, optionally MgO; and optionally ZnO in certain ranges. R.sub.2O+R′O is less than or equal to 25 mol %, where R.sub.2O is the sum of Li.sub.2O, Na.sub.2O, and K.sub.2O and R′O is the sum of CaO, MgO, and ZnO. And, the glass composition includes colorants, such as NiO, CO.sub.3O.sub.4, Cr.sub.2O.sub.3, CuO, and CeO.sub.2 in certain ranges. Further, the constituents are arranged so as to facilitate low diectric, high toughness, desired color, and high strength.

A glass-ceramic article having greater than or equal to 65.00 wt. % and less than or equal to 80.00 wt. % SiO.sub.2, greater than 4.00 wt. % and less than or equal to 12.00 wt. % Al.sub.2O.sub.3, greater than or equal to 0.10 wt. % and less than or equal to 3.5 wt. % P.sub.2O.sub.5, greater than or equal to 8.00 wt. % and less than or equal to 17.00 wt. % Li.sub.2O, greater than or equal to 4.00 wt. % and less than or equal to 15.00 wt. % ZrO.sub.2, and greater than or equal to 0.05 wt. % and less than or equal to 4.00 wt. % CaO.

An ion exchange tank is provided. The ion exchange tank includes a processing chamber and an additive chamber separated by a weir system, the weir system having a flow channel fluidly connecting the processing chamber to the additive chamber, wherein the flow is divided from the additive chamber by a first partition and divided from the processing chamber by a second partition, wherein the additive chamber comprises a solids-absorbing material disposed therein.

A glass-based article includes a first major surface and a first compressive stress region extending to a first depth of compression from the first major surface. The glass-based article includes a second major surface including a first surface portion and one or more edge surface portions recessed from the first surface portion. The glass-based article includes a second compressive stress region extending to a second depth of compression from the first surface portion. Additionally, methods of manufacturing a glass-based article are disclosed.