Glass fiber used as a soil-free cultivation substrate

摘要

The present invention relates to glass fibers used as a constituent of a soilless cultivation substrate. Its composition consists mainly of ingredients having the weight percentages indicated below:;55-70% SiO₂, 1-8% Al₂O₃, 5-9% CaO, 1.5-4% MaO, 13-18. 5% Na₂O, 0.5-10% K₂O, 0-4% Fe₂O₃, 0-4% ZnO, 0-4 MnO, 0-4% TiO₂, 0-4% P₂O₅, Impurities less than 1%, B₂O₃, Li₂Total content of O and F is 1% or less.