Mask filter and method of manufacturing the same, and particle-trapping mask

Abstract

An aspect of the present invention relates to a mask filter, wherein wet nonwoven fabric comprised of synthetic fiber is folded up into a concentric circular pleat form, and the synthetic fiber comprises 10 to 50 mass percent of short fiber A having a fiber length ranging from 0.1 to 1 mm and a fiber diameter ranging from 100 to 1,000 nm, and further comprises binder fiber B having a fiber length ranging from 5 to 10 mm and a fiber diameter ranging from 6 to 15 μm, and fiber C of greater fiber length and fiber diameter than short fiber A and smaller fiber length and fiber diameter than binder fiber B.

1 . A mask filter, wherein wet nonwoven fabric comprised of synthetic fiber is folded up into a concentric circular pleat form, and
 the synthetic fiber comprises:   10 to 50 mass percent of short fiber A having a fiber length ranging from 0.1 to 1 mm and a fiber diameter ranging from 100 to 1,000 nm,   and further comprises:   binder fiber B having a fiber length ranging from 5 to 10 mm and a fiber diameter ranging from 6 to 15 μm, and   fiber C of greater fiber length and fiber diameter than short fiber A and smaller fiber length and fiber diameter than binder fiber B.   
     
     
         2 . The mask filter according to  claim 1 , wherein the synthetic fiber comprises 50 to 90 mass percent of a total quantity of binder fiber B and fiber C. 
     
     
         3 . The mask filter according to  claim 1 , which has a DOP particle filtration efficiency of equal to or greater than 80 percent and a pressure loss of equal to or less than 300 Pa. 
     
     
         4 . The mask filter according to  claim 1 , which has a mass per unit area of 80 to 180 g/m 2 . 
     
     
         5 . The mask filter according to  claim 1 , which has a filter thickness ranging from 0.4 to 1.5 mm, a pleat height ranging from 5 to 30 mm, a pleat outer diameter at the outermost circumference position ranging from 50 to 120 mm, and a total number of pleats ranging from 6 to 15. 
     
     
         6 . The mask filter according to  claim 1 , which has a total weight ranging from 2 to 12 g. 
     
     
         7 . The mask filter according to  claim 1 , wherein the short fiber A is a polyester fiber. 
     
     
         8 . The mask filter according to  claim 1 , wherein the binder fiber B is a core-in-sheath composite fiber with a core portion of polyethylene terephthalate and a sheath portion of copolymer polyester. 
     
     
         9 . The mask filter according to  claim 1 , wherein the fiber C is a polyester fiber. 
     
     
         10 . A method of manufacturing the mask filter according to  claim 1 , which comprises folding up the nonwoven fabric into a concentric circular pleat form while in a wet state. 
     
     
         11 . A particle-trapping mask comprising the mask filter according to  claim 1 .