Low dielectric glass and fiber glass
Glass compositions are provided that are useful in a variety of applications including, for example, electronics applications, reinforcement applications, and others. Some embodiments of glass compositions can provide desirable dielectric constants, desirable dissipation factors, and/or desirable mechanical properties while also having desirable fiber forming properties.
1. A glass composition suitable for fiber forming, comprising:
SiO 2 69-77 weight percent;
B 2 O 3 4.5-<7 weight percent;
Al 2 O 3 4.5-11 weight percent;
MgO 4-12.5 weight percent;
CaO 0-<4.9 weight percent;
Li 2 O 0-4 weight percent;
Na 2 O 0-2 weight percent;
K 2 O 0-1 weight percent;
Fe 2 O 3 0-1 weight percent;
F 2 0-2 weight percent;
TiO 2 0-2 weight percent; and
other constituents 0-5 weight percent total.
2. The composition of claim 1 , wherein the B 2 O 3 content is 5 to less than 7 weight percent.
3. The composition of claim 1 , wherein the CaO content is greater than 1.0 weight percent.
4. The composition of claim 1 , wherein the MgO content is greater than 5.0 weight percent.
5. The composition of claim 1 , wherein the MgO content is less than 6.0 weight percent.
6. The composition of claim 1 , wherein the Al 2 O 3 content is less than 8 weight percent.
7. The composition of claim 1 , wherein the MgO+CaO content is less than 16 weight percent.
8. The composition of claim 1 , wherein the MgO+CaO content is 7-16 weight percent.
9. The composition of claim 1 , wherein the (Li 2 O+Na 2 O+K 2 O) content is less than 2 weight percent.
10. The composition of claim 1 , wherein the Li 2 O content is 0.4-2.0 weight percent.
11. The composition of claim 1 , wherein the composition contains essentially no BaO and essentially no ZnO.
12. A plurality of glass fibers formed from the composition of claim 1 .
13. A glass composition suitable for fiber forming, comprising:
SiO 2 69-77 weight percent;
B 2 O 3 5-<7 weight percent;
Al 2 O 3 4.5-11 weight percent;
MgO 5-12.5 weight percent;
CaO 0-<4.9 weight percent;
Li 2 O 0-4 weight percent;
Na 2 O 0-2 weight percent;
K 2 O 0-1 weight percent;
Fe 2 O 3 0-1 weight percent;
F 2 0-2 weight percent;
TiO 2 0-2 weight percent; and
other constituents 0-5 weight percent total, wherein the MgO+CaO content is less than 16 weight percent.
14. The composition of claim 13 , wherein the MgO content is less than 6.0 weight percent.
15. The composition of claim 13 , wherein the Al 2 O 3 content is less than 8 weight percent.
16. The composition of claim 13 , wherein the MgO+CaO content is 7 to less than 16 weight percent.
17. The composition of claim 13 , wherein the (Li 2 O+Na 2 O+K 2 O) content is less than 2 weight percent.
18. The composition of claim 13 , wherein the Li 2 O content is 0.4-2.0 weight percent.
19. The composition of claim 13 , wherein the composition contains essentially no BaO and essentially no ZnO.
20. A plurality of glass fibers formed from the composition of claim 13 .