FILTER MEDIUM, FILTER ELEMENT, AND FILTER MEDIUM MANUFACTURING METHOD

To provide a filter medium that is small in pressure loss and has a deodorization function, and provide a filter element comprising the filter medium and a filter medium manufacturing method.SOLUTION: A filter medium of the present invention is provided in which the difference between the apparent density of a portion having the highest apparent density and the apparent density of a portion having the lowest apparent density in a cross section in the thickness direction of one fiber assembly A is 0.030 g/cm3 or more, and also a portion of low apparent density and a portion of high apparent density are present in the fiber assembly A. Accordingly, the filter medium that is small in pressure loss and has a deodorization function can be achieved because air is easy to pass in the portion of the low apparent density. Also, the filter medium of the present invention can be manufactured by that another fiber assembly A precursor is stacked on a main surface having deodorization particles of a fiber assembly B precursor and is pressurized after arranging deodorization particles on one main surface of the fiber assembly B precursor, and at least the fiber assembly A precursor is partially deformed in the thickness direction.SELECTED DRAWING: Figure 1 【課題】圧力損失が小さい、脱臭機能を有する濾材、前記濾材からなるフィルタエレメント、及び濾材の製造方法を提供すること。【解決手段】本発明の濾材は、一方の繊維集合体Ａの厚さ方向の断面における最も見掛密度の高い部分の見掛密度と、最も見掛密度の低い部分の見掛密度の差が０．０３０ｇ／ｃｍ３以上と、繊維集合体Ａに見掛密度が低い部分と、見掛密度が高い部分が存在し、見掛密度が低い部分は空気が通りやすいことから、圧力損失が小さい、脱臭機能を有する濾材が実現できる。また、本発明の濾材は、繊維集合体Ｂ前駆体の一方の主面上に脱臭粒子を配置してから、繊維集合体Ｂ前駆体の脱臭粒子を有する主面上に別の繊維集合体Ａ前駆体を積層するとともに加圧し、少なくとも繊維集合体Ａ前駆体を厚さ方向に部分的に変形させることで製造できる。【選択図】図１