| 摘要 |
PROBLEM TO BE SOLVED: To provide a chemical filter, which can efficiently remove harmful ionic substances and prevents the recontamination of a clean room. SOLUTION: In this chemical filter which removes harmful ionic substances, the volatilization volume of a compound having phenolic hydroxyl groups, among gas components generated from the chemical filter into a gas phase, is 172 or less of that of the toluene. Volatile components adsorbed on the chemical filter are removed under a reduced pressure until the volatilization volume of the compound having phenolic hydroxyl groups becomes 1/2 or less of that of toluene. |
