Patent ID: 8449828

Claim:
A chemical cartridge, comprising: a chemical-impregnated body comprising an air-permeable and liquid-absorptive sheet impregnated with a chemical; and a retainer receptacle which contains the chemical-impregnated body; wherein: the retainer receptacle comprises a central liquid pool recess formed at a central area of the retainer receptacle such that a liquid chemical stored in the central liquid pool recess is permeable towards a peripheral area of the sheet; the retainer receptacle further comprises a peripheral liquid pool recess formed at a peripheral area of the retainer receptacle, the peripheral liquid pool recess being independent from said central liquid pool recess, and wherein a liquid chemical stored in the peripheral liquid pool recess is permeable towards a central area of the sheet; the retainer receptacle comprises a receptacle base member and a cover member; said receptacle base member comprises a central support section, a peripheral support section, a plurality of connecting sections connecting the central and peripheral support sections to each other, and a first airflow passage section defined by said support and connecting sections; said cover member comprises a central hold section, a peripheral hold section, a plurality of connecting sections connecting the central and peripheral hold sections to each other, and a second airflow passage section defined by said hold and connecting sections; said central liquid pool recess is formed in said central support section and a supply port communicating with said central liquid pool recess is formed in said central hold section; and said peripheral liquid pool recess is formed in said peripheral support section and a peripheral supply section communicating with said peripheral liquid pool recess is formed in said peripheral hold section.