Filter cloth for bag filter, method for producing the same, and bag filter
The prevent invention addresses the problem of providing a filter cloth for a bag filter, which has excellent collection efficiency, has excellent collection efficiency, provides low pressure drop and is resistant to clogging, and also has excellent dust-off ability; a method for producing the same; and a bag filter. As a means for resolution, a nonwoven fabric containing an ultrafine fiber having a fiber diameter D of 200 to 2,000 nm is laminated on a base material to form a filter cloth for a bag filter.
1. A filter cloth for a bag filter, comprising:
a nonwoven fabric and a base fabric,
the filter cloth for a bag filter being characterized in that the nonwoven fabric contains an ultrafine fiber having a fiber diameter D of 200 to 2,000 nm and the nonwoven fabric has a porosity within a range of 92 to 97%,
wherein the ultrafine fiber has a fiber length of 1.0 to 20 mm and the nonwoven fabric is a spunlace nonwoven fabric.
2. The filter cloth for a bag filter according to claim 1 , wherein the ratio L/D of fiber length L to fiber diameter D of the ultrafine fiber is within a range of 200 to 4,000.
3. The filter cloth for a bag filter according to claim 1 , wherein the ultrafine fiber is a polyester fiber or a polyphenylene sulfide fiber.
4. The filter cloth for a bag filter according to claim 3 , wherein the polyester fiber has an elongation of less than 60%.
5. The filter cloth for a bag filter according to claim 1 , wherein the nonwoven fabric contains the ultrafine fiber in a proportion of 3 to 50 wt %.
6. The filter cloth for a bag filter according to claim 1 , wherein the nonwoven fabric has a multilayer structure.
7. The filter cloth for a bag filter according to claim 1 , wherein the nonwoven fabric has a weight per unit within a range of 10 to 90 g/m 2 .
8. The filter cloth for a bag filter according to claim 1 , wherein the nonwoven fabric has a thickness within a range of 0.2 to 0.6 mm.
9. The filter cloth for a bag filter according to claim 1 , wherein the base fabric is a needle-punched nonwoven fabric including a scrim having a weight per unit of 40 to 120 g/m 2 .
10. The filter cloth for a bag filter according to claim 1 , wherein the base fabric is a spunbond nonwoven fabric having a weight per unit of 100 to 400 g/m 2 .
11. A method for producing the filter cloth for a bag filter according to claim 1 , comprising:
from a sea-island composite fiber including a sea component and an island component, dissolving away the sea component to give an ultrafine fiber having a fiber diameter D of 200 to 2,000 nm;
preparing a nonwoven fabric using the ultrafine fiber; and
laminating the nonwoven fabric on a base material.
12. A bag filter using the filter cloth for a bag filter according to claim 1 , wherein the nonwoven fabric is placed on a dust inflow side.
13. The bag filter according to claim 12 , being sewn or pleated.
14. The filter cloth for a bag filter according to claim 3 , wherein the polyester fiber has an elongation of 60% or more.
15. The filter cloth for a bag filter according to claim 2 , wherein the ultrafine fiber is a polyester fiber or a polyphenylene sulfide fiber.
16. The filter cloth for a bag filter according to claim 15 , wherein the polyester fiber has an elongation of less than 60%.
17. The filter cloth for a bag filter according to claim 15 , wherein the polyester fiber has an elongation of 60% or more.
18. The filter cloth for a bag filter according to claim 3 , wherein the ultrafine fiber is a polyphenylene sulfide fiber.
19. The filter cloth for a bag filter according to claim 18 , wherein the polyphenylene sulfide fiber comprises at least 70 mol % p-phenylene sulfide units.
20. The filter cloth for a bag filter according to claim 1 , wherein the ultrafine fiber has a fiber length of 5 to 20 mm.