# US 2018/0022635 A1 · Transparent silicate glasses with high fracture toughness > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0022635 A1 - Document ID: US20180022635A1 - Status: Published application - Kind: A1 - Application number: 15/650,152 - Filed: 2017-07-14 - Published: 2018-01-25 - Earliest claimed: 2016-07-21 - Assignees: Corning Incorporated - Applicants: Corning Incorporated - Inventors: Jian Luo; John Christopher Mauro - Web page: https://patentgrep.com/patent/US20180022635A1 ## CPC - C03C 3/097: containing phosphorus, niobium or tantalum - C03B 1/00: Preparing the batches (chemical compositions C03C) - C03C 3/095: containing rare earths - H05K 5/03: Covers - C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS - C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract Provided herein are glass based articles comprising SiO2, Al2O3, and two or more metal oxides selected from the group consisting of La2O3, BaO, Ta2O5, Y2O3, and HfO2. The glass based articles typically are characterized by a high fracture toughness (e.g., at least 0.86 MPa*m0.5), a high Young's modulus value (e.g., at least 85 GPa) and/or a stress optical coefficient (SOC) of not more than 3 Brewster (e.g., about 1.3 Brewster to about 2 Brewster). Also provided herein are glass based articles comprising SiO2 and two or more of MxOy, wherein M is Ba, La, Ta, Y, Al or Hf; wherein the total amount of SiO2 is the same or substantially the same as that of a reference glass based article comprising two or more binary compositions of MxOy—SiO2, wherein the reference glass based article has the same molar percentage of each MxOy, and the molar ratio of MxOy to SiO2 in each binary composition is 4/(c*x), wherein c is the number of charges of M. ## Claims ### Claim 1 A glass based article comprising: SiO2 in the range of about 35 mol % to about 80 mol %; Al2O3 in the range of about 1 mol % to about 15 mol %; and two or more metal oxides selected from the group consisting of La2O3, BaO, Ta2O5, Y2O3, and HfO2, wherein the combined molar percentages of the two or more metal oxides are at least 15 mol %. ### Claim 2 (depends on 1) The glass based article of claim 1, comprising HfO2 in the range of about 1 mol % to about 7 mol %. ### Claim 3 (depends on 1) The glass based article of claim 1, comprising Y2O3 in the range of about 1 mol % to about 29 mol %. ### Claim 4 (depends on 1) The glass based article of claim 1, comprising Ta2O5 in the range of about 1 mol % to about 30 mol %. ### Claim 5 (depends on 1) The glass based article of claim 1, comprising La2O3 in the range of about 1 mol % to about 29 mol %. ### Claim 6 (depends on 1) The glass based article of claim 1, comprising BaO in the range of about 1 mol % to about 33 mol %. ### Claim 7 (depends on 1) The glass based article of claim 1, comprising: SiO2 in the range of about 40 mol % to about 75 mol %; Al2O3 in the range of about 3 mol % to about 10 mol %; La2O3 in the range of about 2 mol % to about 25 mol %; Ta2O5 in the range of about 2 mol % to about 20 mol %; Y2O3 in the range of about 2 mol % to about 21 mol %; HfO2 in the range of about 1.5 mol % to about 6 mol %; and BaO in the range of about 2 mol % to about 25 mol %. ### Claim 8 (depends on 1) The glass based article of claim 1, comprising: SiO2 in the range of about 45 mol % to about 70 mol %; Al2O3 in the range of about 4 mol % to about 9 mol %; La2O3 in the range of about 4 mol % to about 22 mol %; Ta2O5 in the range of about 2.5 mol % to about 18 mol %; Y2O3 in the range of about 4 mol % to about 21 mol %; HfO2 in the range of about 2 mol % to about 5 mol %; and BaO in the range of about 4 mol % to about 25 mol %. ### Claim 9 (depends on 1) The glass based article of claim 1, comprising not more than 5 mol % of alkali metals. ### Claim 10 (depends on 1) The glass based article of claim 1, comprising not more than 5 mol % of boron. ### Claim 11 (depends on 1) The glass based article of claim 1, characterized by having (i) a fracture toughness of at least 0.86 MPa*m0.5; (ii) a Young's modulus value of at least 85 GPa; and/or (iii) a stress optical coefficient (SOC) of not more than 3 Brewster. ### Claim 12 A glass based article comprising: SiO2, Al2O3, and two or more metal oxides selected from the group consisting of La2O3, BaO, Ta2O5, Y2O3, and HfO2, wherein the glass based article is characterized by a fracture toughness of at least 0.86 MPa*m0.5. ### Claim 13 (depends on 12) The glass based article of claim 12, wherein the glass based article comprises not more than 5 mol % of alkali metals and boron. ### Claim 14 (depends on 12) The glass based article of claim 12, wherein the two or more metal oxides comprise La2O3, BaO, Ta2O5, Y2O3, and HfO2. ### Claim 15 (depends on 12) The glass based article of claim 12, wherein the glass based article has (i) a fracture toughness of about 1.0 MPa*m0.5 to about 1.6 MPa*m0.5; (ii) a Young's modulus value of about 110 GPa to about 140 GPa; and/or (iii) a stress optical coefficient (SOC) of about 1.3 Brewster to about 2 Brewster. ### Claim 16 A glass based article comprising SiO2 and two or more of MxOy, wherein M is Ba, La, Ta, Y, Al or Hf; wherein the total amount of SiO2 is the same or substantially the same as that of a reference glass based article comprising two or more binary compositions of MxOy—SiO2, wherein the reference glass based article has the same molar percentage of each MxOy, and the molar ratio of MxOy to SiO2 in each binary composition is 4/(c*x), wherein c is the number of charges of M. ### Claim 17 (depends on 16) A process for preparing the glass based article of claim 16, comprising mixing two or more binary compositions of MxOy—SiO2, wherein M is Ba, La, Ta, Y, Al or Hf; and heating the two or more binary compositions of MxOy—SiO2 to form the glass based article. ### Claim 18 (depends on 17) The process of claim 17, wherein the two or more binary compositions of MxOy—SiO2 comprise BaO—SiO2, La2O3—SiO2, Ta2O5—SiO2, Y2O3—SiO2, Al2O3—SiO2 and HfO2—SiO2, and wherein the SiO2 is in a total amount of about 30 mol % to about 80 mol %. ### Claim 19 (depends on 17) The glass based article prepared by the process of claim 17. ### Claim 20 (depends on 1) A consumer electronic device comprising a glass based article of claim 1. ### Claim 21 (depends on 12) A consumer electronic device comprising a glass based article of claim 12. ### Claim 22 (depends on 16) A consumer electronic device comprising a glass based article of claim 16.