| 摘要 |
This filter material (20) is provided with a first PTFE porous membrane (11), a first air-permeable support material (12), a second PTFE porous membrane (13), and a second air-permeable support material (14). The surface of the filter material (20) is formed by the first PTFE porous membrane (11). The adhesive strength (A1) between the first PTFE porous membrane (11) and the first air-permeable support material (12) as measured by a 180° peel test is greater than 1.2 N/25 mm. The first air-permeable support material (12) is an embossed non-woven fabric that has one or more recesses and one or more protrusions. The ratio of the area of the recess or of the total area of the recesses to the area of the embossed non-woven fabric that constitutes the first air-permeable support material (12) is greater than 15%. |
