Biosoluble composition of glass fibres for the production of glass wools and the like

摘要

The composition includes the following compounds in the specified weight percentages of the whole composition: %SiO2 60-70; %Al2O3 1-3; %Na2O+%K2O > 17; %CaO ≤ 8 %MgO 2-4%; CaO+%MgO < 10.5; %R2O/%RO > 1.65; %B2O3 4.5-8; where RO is the sum of oxides of elements pertaining to column 2A of the Periodic Table and R2O is the sum of oxides of elements pertaining to column 1A of the Periodic Table, the composition further including up to about 2 % in weight of impurities and other conventional compounds such as Fe2O3, but P2O5 and SO3 being excluded from the composition. The invention provides biosoluble fibres for glass wools with relatively low Kl values. <IMAGE>