| 摘要 |
<p>PROBLEM TO BE SOLVED: To enhance the deodorizing efficiency of a malodorous substance which pollutes indoor air, to prevent the lowering of the capacity of fibrous activated carbon within a short period of time and to reduce the weight and thickness of a filter while enhancing the workability of the filter. SOLUTION: In a sheetlike or pleated filter medium comprising a plurality of layers made of a nonwoven fabric using binder fibers, at least one layer is a first adsorbing layer impregnated with a water-soluble chemical agent chemically reacted with an indoor malodorous substance and other one layer is a second adsorbing layer wherein fibrous activated carbon is fixed by binder fibers and the first and second adsorbing layers are bonded by spot lump parts formed by an ultrasonic bonding method.</p> |
