Nitto-Denko Corporation

Asuka Onohara

Yoshiki Ikeyama

Nobuaki Maruoka

Hajime Yamamoto

Naofumi Kosaka

Yuta Kuroki

Ryota Masuda

Keiko Fujiwara

The present invention provides an air-permeable filter capable of maintaining excellent air permeation performance without being clogged even in an environment involving exposure to an oil, oil mist, or ink. The present invention relates to an air-permeable filter including a porous membrane having a surface coated with an oil-repellent agent, the filter being characterized in that a sliding angle of 20 &#x3bc;l of hexadecane or pentadecane on the surface of the filter is 60&#xb0; or less.

Air-permeable filter provided with oil repellency

A gas-permeable filter provided with oil repellency is provided. The gas-permeable filter includes a porous membrane having a surface coated with an oil-repellent agent. The oil-repellent agent includes a linear fluorine-containing hydrocarbon group represented by &#x2014;RCFCHCFor &#x2014;RCF, and the porous membrane is a stretched polytetrafluoroethylene (PTFE) porous membrane. Here, Rand Rare each independently an alkylene group having 1 to 12 carbon atoms or a phenylene group. The gas-permeable filter is provided with oil repellency without significant reduction in gas permeability.

Gas-permeable filter provided with oil repellency

Disclosed is an air-permeable filter with an adhesive layer. This air-permeable filter is imparted with oil repellency and includes: a porous membrane having a surface coated with an oil-repellent agent; and an adhesive layer disposed on the surface. The oil-repellent agent contains a linear fluorine-containing hydrocarbon group represented by (1) &#x2014;RCFCHCFor (2) &#x2014;RCF, where Rand Rare each independently an alkylene group having 1 to 12 carbon atoms or a phenylene group. This air-permeable filter is imparted with oil repellency without significantly reducing its adhesive strength to the adhesive layer.

Oil repellency-imparted air-permeable filter with adhesive layer

Growing community of inventors

Osaka, Japan

Asuka Onohara