Borate-free glass composition and insulating glass fiber that can be formed into fibrous form and method for producing the same

摘要

A glass composition capable of being spun into fibres has the following components expressed as weight percent: SiO2 - 66 to 73; Al2O3 - 0.85 to 5; R2O (= Na2O + K2O) - 14 to 17.5; CaO - 6.5 to 12; and SiO2 + A2O3 - 69 to 74. The composition is free of boric oxide and consequently avoids pollution difficulties associated with that compound, yet it can be used in high temperature spinners to produce durable fibres.