ALEXANDRIA, Va., Sept. 3 -- United States Patent no. 12,403,429, issued on Sept. 2, was assigned to NITTO DENKO Corp. (Osaka, Japan).
"Filter medium and filter unit" was invented by Shunsuke Masaki (Osaka, Japan) and Masaaki Mori (Osaka, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A filter medium of the present disclosure has a laminate structure composed of a first polytetrafluoroethylene (PTFE) porous membrane, a first air-permeable supporting member, a second PTFE porous membrane, and a second air-permeable supporting member laminated in this order. The first PTFE porous membrane constitutes an exposed surface of the filter medium. A ratio of a transmittance of the first PTFE porous membrane to a...