| 摘要 |
A flat-fold filtering face piece respirator 10 that comprises a mask body 12 that has a transversely-extending line of demarcation 22 and a longitudinal axis 34. First and second weld patterns 32a, 32b are disposed above and not traversing the line of demarcation on each side of the longitudinal axis 34, respectively. Third and fourth weld patterns 32c, 32d are disposed below and not crossing the line of demarcation 22 on each side of the longitudinal axis 34, respectively. Each of the first, second, third, and fourth weld patterns 32a-32d is a two-dimensional enclosed pattern. This combined weld patterns can provide a mask body that exhibits crush resistance without the need for additional or heavier layers, which may cause higher pressure drops across the filtering structure. |
