| 摘要 |
Alkali-resistant glass fibres, in the form of continuous-filament for use as reinforcement in cementitious products, or in the form of glass wool, are given enhanced alkali resistance by the incorporation of ThO2. The fibres are formed from a glass composition comprising, in weight percentages: -SiO2 50 to 75% -ThO2 + ZrO2 5 to 30% with ThO2 at least 0.4% -R2O 0 to 25% -R'O 0 to 40% -R2O + R'O 10 to 40% -Rare earth oxides 0 to 20% - the content of ThO2 being at least 1% when the content of ZrO2 is less than 6% but not exceeding 9.5% when ZrO2 exceeds 8%, where R2O represents Na2O, K2O or LiO2, with K2O not exceeding 10% and Li2O not exceeding 5% and R'O represents one or more of MgO, CaO, SrO, BaO, ZnO and MnO. |
