| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a practicable high-performance filter medium which is composed of a cellulose nonwoven fabric having high heat resistance, high chemical resistance, and excellent adsorptivity which are characteristics inherent to cellulose, and also having high trap efficiency, high physical property stability, and excellent handleability. <P>SOLUTION: The filter medium comprises the cellulose nonwoven fabric comprising cellulose fibers having a maximum fiber diameter of 2,500 nm or below and satisfies all of the following requirements (1) to (6): (1) the degree of polymerization (DP) of the cellulose fibers is 500 or above, (2) the weight ratio of the cellulose fibers in the filter medium is 10 wt.% or above, (3) the basis weight of the filter medium is 6 g/m<SP POS="POST">2</SP>or above and 150 g/m<SP POS="POST">2</SP>or below, (4) the resistance to air-permeation of the filter medium is 10 s/100 mL or above and 2,000 s/100 mL or below, (5) the standard deviation of the absorbance of the filter medium is 350 or below, and (6) the tensile strength of the filter medium corresponding to the basis weight of 10 g/m<SP POS="POST">2</SP>is 6 N/15 mm or above. <P>COPYRIGHT: (C)2012,JPO&INPIT |
