Air filter medium, air filter pack and air filter unit comprising the same, and method for producing air filter medium
US6416562B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 18, 2000 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Jul 25, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249978
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An air filter medium comprising a porous polytetrafluoroethylene film and an air-permeable support member laminated on at least one surface of said porous film and having a PF1 value exceeding 22, which is calculated according to the following formula:PF1=[−log(Penetration (%)/100)/Pressure loss (mmH2O)]×100in which the penetration (%)=100−Collection efficiency from a pressure loss (unit: mmH2O) measured when an air is flowed through the air filter medium at a flow velocity of 5.3 cm/sec. and a collection efficiency (unit: %) measured using dioctyl phthalate having a particle size of 0.10 to 0.12 &mgr;m. This air filter medium has a low pressure loss and a high collection efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.