| abstract |
Scaly glass 10, the heat resistance and the chemical durability is improved, 60≤SiO 2 ≤70, 5≤Al 2 O 3 ≤15, 1≤MgO≤10, 10≤CaO≤25 and 4 <(Li 2 O + Na 2 O + K 2 O Formed from a glassy material satisfying < 9 (the above numbers all refer to mass%). It is preferable that the temperature difference (DELTA) T which subtracted the devitrification temperature from the working temperature of glassy raw material is 0-200 degreeC. It is preferable that the glass transition temperature of a glassy raw material is 560-750 degreeC. It is preferable that (DELTA) W which is an index of acid resistance of a glassy raw material is 0.05-1.2 mass%. |