Patent ID: 8586491

Claim:
A high performance glass fiber produced from a composition comprising: SiO 2 in an amount from about 60.5 to about 70.5 weight percent of the total composition; Al 2 O 3 in an amount from about 10 to about 24.5 weight percent of the total composition; RO in an amount from about 10 to about 24.0 weight percent of the total composition, said RO being the sum of MgO, SrO, CaO, and BaO, wherein the amount of CaO present in said RO comprises at least 4 weight percent of the total composition and the amount of MgO comprises at least 5 weight percent of the total composition; less than 1 weight percent TiO 2 ; and alkali metal oxides in an amount from about 0 to about 3 weight percent of the total composition, wherein said glass fiber is resistant to corrosion and said composition has a ΔT of at least about 80° F.