The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 23, 2019
Filed:
Mar. 20, 2015
Daikin Industries, Ltd., Osaka-shi, Osaka, JP;
Yoshiyuki Shibuya, Yuki, JP;
Hideyuki Kiyotani, Settsu, JP;
Kunihiko Inui, Settsu, JP;
Li Bao, Yuki, JP;
Shinichi Chaen, Settsu, JP;
Seigo Yamamoto, Settsu, JP;
Makoto Kobayashi, Yuki, JP;
Hitoshi Niinuma, Yuki, JP;
Daikin Industries, Ltd., Osaka, JP;
Abstract
A filtering medium includes first and second porous membranes mainly composed of fluororesin, and a plurality of air permeable supports to support the first and second membranes. The second membrane is disposed downstream of the first membrane. When air containing polyalphaolefin particles with a count median diameter of 0.25 μm is continuously passed through at a flow rate of 5.3 cm/sec and pressure loss is increased by 250 Pa, the first membrane has a dust retention amount larger than the second membrane. The filtering medium has a pressure loss of less than 200 Pa when air is passed through at a flow rate of 5.3 cm/sec. A collecting efficiency of NaCl particles with a particle diameter of 0.3 μm is 99.97% or more when air containing the NaCl particles is passed through at a flow rate of 5.3 cm/sec. The dust retention amount is 25 g/mor more.