High alkali glass composition

Abstract

A glass composition useful in preparing fiberglass comprises 12 to 25 weight % CaO; 12 to 16 weight % Al 2 O 3 ; 52 to 62 weight % SiO 2 ; 0.05 to 0.8 Fe 2 O 3 ; and greater than 2 up to about 8 weight % alkali metal oxide.

1 . A glass composition useful in preparing fiberglass comprising:
 12 to 25 weight % CaO;   12 to 16 weight % Al 2 O 3 ;   52 to 62 weight % SiO 2 ;   0.05 to 0.8 Fe 2 O 3 ; and   greater than 2 up to about 8 weight % alkali metal oxide.   
     
     
         2 . The glass composition of  claim 1 , comprising 16 to 25 weight % CaO. 
     
     
         3 . The glass composition of  claim 1 , further comprising B 2 O 3  in an amount up to 10 weight %. 
     
     
         4 . The glass composition of  claim 1 , further comprising MgO in an amount up to 5 weight %. 
     
     
         5 . The glass composition of  claim 1 , further comprising TiO 2  in an amount up to 1.5 weight %. 
     
     
         6 . The glass composition of  claim 1 , further comprising fluorine in an amount up to 1.0 weight %. 
     
     
         7 . The glass composition of  claim 1 , comprising greater than 5 weight % recycled glass. 
     
     
         8 . The glass composition of  claim 7 , comprising up to 55 weight % recycled glass. 
     
     
         9 . The glass composition of  claim 1 , comprising up to 55 weight % recycled glass. 
     
     
         10 . The glass composition of  claim 1 , wherein the alkali metal oxide comprises one or more alkali metal oxides selected from the group consisting of Na 2 O, K 2 O, and Li 2 O. 
     
     
         11 . The glass composition of  claim 1 , comprising Li 2 O in an amount up to 5 weight %. 
     
     
         12 . The glass composition of  claim 3 , comprising about 3.5 to about 5.5 weight % B 2 O 3 . 
     
     
         13 . The glass composition of  claim 1 , wherein the glass composition has a T log3  temperature of less than 2300° F. 
     
     
         14 . The glass composition of  claim 1 , wherein the glass composition has a T log3  temperature of less than 2220° F. 
     
     
         15 . The glass composition of  claim 1 , wherein the glass composition has a T log3  temperature of less than 2160° F. 
     
     
         16 . The glass composition of  claim 1 , wherein the glass composition has a liquidus temperature at least 100° F. less than the T log3  temperature of the glass composition. 
     
     
         17 . The glass composition of  claim 1 , wherein the glass composition has a liquidus temperature at least 140° F. less than the T log3  temperature of the glass composition. 
     
     
         18 . The glass composition of  claim 1 , wherein the glass composition has a liquidus temperature at least 160° F. less than the T log3  temperature of the glass composition. 
     
     
         19 . A method of preparing fiberglass using the glass composition of  claim 1 . 
     
     
         20 . The method of  claim 19 , comprising employing a non-Pt/Rh bushing.