Filter

Abstract

Damage is not caused even when oil mist in a gas is trapped, and clogging of a filter paper due to an oil film can be less likely to occur. A filtration member formed by folding a filter paper for trapping oil mist in a gas into a corrugated shape in which mountain folds and valley folds are alternately repeated is provided. The filter paper includes a nanofiber layer formed of polyolefin fibers. In the nanofiber layer, a content of fibers having a fiber diameter of 0.2 μm to 0.4 μm is 3% or more, a content of fibers having a fiber diameter of 0.4 μm to 0.6 μm is 24% or more, a content of fibers having a fiber diameter of 0.6 μm to 0.8 μm is 15% or more, and a content of fibers having a fiber diameter of 0.8 μm to 1.0 μm is 9% or more.

Dependencies are inferred from the claim text.