Filtering device, purification device, and method for manufacturing chemical liquid

A filtering device for obtaining a chemical liquid by purifying a liquid to be purified, the device comprising:

• an inlet portion;
• an outlet portion;
• a filter A;
• at least one filter B different from the filter A;
• a flow path which includes the filter A and the filter B arranged in series between the inlet portion and the outlet portion and extends from the inlet portion to the outlet portion, and
• a tank arranged in series between the filter A and the filter B on the flow path,
• wherein the filter A includes at least one selected from the group consisting of a first porous membrane having a porous base material made of polytetrafluoroethylene and a non-crosslinked coating which is formed to cover the porous base material and contains a perfluorosulfonic acid polymer and a second porous membrane containing polytetrafluoroethylene blended with a perfluorosulfonic acid polymer,
• the filter B includes at least one filter BU disposed on an upstream side of the filter A on the flow path, and
• the filter BU contains a resin having an anion exchange group.