PURPOSE: To exchange filters without polluting a clean area by combining the upstream filter made of fibers having hydroxyl groups on the surface with the downstream filter which collects fine particles with a high efficiency and does not release boron.
CONSTITUTION: An air filter is made by the combination of an upstream filter 11 made of fibers having hydroxyl groups on the surface or an active carbon layer and a downstream filter 12 which collects fine particles with high efficiency and does not release boron. The downstream filter 12 consists of a quartz glass fiber layer the boron elution into pure water (65°C×120hr) of which does not exceed 1.5×10-5 grams per gram of fiber or of a glass or polypropylene fiber layer which has the same boron elution and collects 99.97% or more of particles of 0.3μm diameter. The upstream filter 11 is placed on the suction side of a blower 10, while the downstream filter 12 is located on the discharge side of the blower 10.
| JP6458245 | Cooking system |
SUMIOKA MASAYUKI
ASAHI TSUKASA
