Glass plate and process for its production
View Patent ↗A cover glass includes a soda lime silica glass including SiO 2 , MgO, CaO, Na 2 O and Al 2 O 3 . The SiO 2 content in the silica glass is in the range of 60 wt % to 71.1 wt %, the MgO content in the silica glass in the range of 4.5 wt % to 15 wt %, the CaO content in the silica glass in the range of 0.5 wt % to 10 wt %, the Na 2 O content in the silica glass in the range of 10-20 wt %, the Al 2 O 3 content in the silica glass in the range of 0-10.3 wt %, the silica glass has the ratio [MgO]/[CaO] of larger than 1 and the Q value of 20 or larger, and the Q value is obtained by formula, Q =([MgO]/[CaO])X([CaO]+[Na 2 O]−[Al 2 O 3 ]), where [MgO] is the MgO content, [CaO] is the CaO content, [Na 2 O] is the Na 2 O content, and [Al 2 O 3 ] is the Al 2 O 3 content by mass percentage based on oxides.
1. A cover glass, comprising:
a soda lime silica glass comprising Si 0 2 , MgO, CaO, Na 2 O and Al 2 O 3 ,
wherein a content of SiO 2 in the soda lime silica glass is in a range of 60 wt % to 71.1 wt % , a content of MgO in the soda lime silica glass is in a range of 4.5 wt % to 15 wt % , a content of CaO in the soda lime silica glass is in a range of 0.5 wt % to 10 wt % , a content of Na 2 O in the soda lime silica glass is in a range of 10-20 wt % , a content of Al 2 O 3 in the soda lime silica glass is in a range of 0-10.3 wt % , a content of B 2 O 3 is at most 1 wt %, the soda lime silica glass has a ratio [MgO]/[CaO] of larger than 1 and a Q value of at least 20, and the Q value is obtained by formula of Q =([MgO]/[CaO])X([CaO]+[Na 2 O]−[Al 2 O 3 ]),where [MgO] is the content of MgO by mass percentage based on oxide, [CaO] is the content of CaO by mass percentage based on oxide, [Na 2 O] is the content of Na 2 O by mass percentage based on oxide, and [Al 2 O 3 ] is the content of Al 2 O 3 by mass percentage based on oxide.
2. The cover glass according to claim 1 , wherein the content of SiO 2 is in a range of 61.8-71.1 wt % .
3. The cover glass according to claim 1 , wherein the content of SiO 2 is in a range of 62.7-71.1 wt % .
4. The cover glass according to claim 1 , wherein the content of SiO 2 is in a range of 66.5-71.1 wt % .
5. The cover glass according to claim 1 , wherein the content of SiO 2 is in a range of 67.5-71.1 wt % .
6. A cover glass, comprising:
a soda lime silica glass comprising SiO 2 , MgO, CaO, Na 2 O and Al 2 O 3 ,
wherein a content of SiO 2 in the soda lime silica glass is in a range of 60 wt % to 75 wt % , a content of MgO in the soda lime silica glass is in a range of 4.5 wt % to 15 wt % , a content of CaO in the soda lime silica glass is in a range of 1 wt % to 10 wt % , a content of Na 2 O in the soda lime silica glass is in a range of 10-20 wt % , a content of Al 2 O 3 in the soda lime silica glass is in a range of 0-10.3 wt % , a content of B 2 O 3 is at most 1 wt %, the soda lime silica glass has a ratio [MgO]/[CaO] of larger than 1 and a Q value of at least 20, and the Q value is obtained by formula of Q =([Mg 0 ]/[CaO])X([CaO]+[Na 2 O]−[Al 2 O 3 ]),where [MgO] is the content of MgO by mass percentage based on oxide, [CaO] is the content of CaO by mass percentage based on oxide, [Na 2 O] is the content of Na 2 O by mass percentage based on oxide, and [Al 2 O 3 ] is the content of Al 2 O 3 by mass percentage based on oxide.
7. The cover glass according to claim 6 , wherein the content of CaO is in a range of 1 wt % to 5.8 wt % .
8. The cover glass according to claim 6 , wherein the content of CaO is in a range of 1 wt % to 5.7 wt % .
9. The cover glass according to claim 6 , wherein the content of CaO is in a range of 1 wt % to 4.8 wt % .
10. A cover glass, comprising:
a soda lime silica glass comprising SiO 2 , MgO, CaO, Na 2 O and Al 2 O 3 ,
wherein a content of SiO 2 in the soda lime silica glass is in a range of 60 wt % to 75 wt % , a content of MgO in the soda lime silica glass is in a range of 6.4 wt % to 15 wt % , a content of CaO in the soda lime silica glass is in a range 0.5 wt % to 10 wt % , a content of Na 2 O in the soda lime silica glass is in a range of 10-20 wt % , a content of Al 2 O 3 in the soda lime silica glass is in a range of 0-10.3 wt % , a content of B 2 O 3 is at most 1 wt %, the soda lime silica glass has a ratio [MgO]/[CaO] of larger than 1 and a Q value of at least 20, and the Q value is obtained by formula of Q =([Mg 0 ]/[Ca 0 ])X([CaO]+[Na 2 O] 31 [Al 2 O 3 ]),where [MgO] is the content of MgO by mass percentage based on oxide, [CaO] is the content of CaO by mass percentage based on oxide, [Na 2 O] is the content of Na 2 O by mass percentage based on oxide, and [Al 2 O 3 ] is the content of Al 2 O 3 by mass percentage based on oxide.
11. The cover glass according to claim 10 , wherein the content of MgO is in a range of 6.4-14.2 wt % .
12. The cover glass according to claim 10 , wherein the content of MgO is in a range of 6.4-12.3 wt % .
13. The cover glass according to claim 10 , wherein the content of MgO is in a range of 6.4-11.6 wt % .
14. The cover glass according to claim 10 , wherein the content of MgO is in a range of 6.4-10.7 wt % .
15. The cover glass according to claim 10 , wherein the content of MgO is in a range of 6.4-9.9 wt % .
16. The cover glass according to claim 1 , wherein B 2 O 3 is not substantially contained.
17. The cover glass according to claim 6 , wherein B 2 O 3 is not substantially contained.
18. The cover glass according to claim 6 , wherein the content of CaO is in a range of 1 wt % to 4.3 wt % .
19. The cover glass according to claim 6 , wherein the content of CaO is in a range of 1 wt % to 3.7 wt % .
20. The cover glass according to claim 10 , wherein B 2 O 3 is not substantially contained.