SPUN-BONDED NONWOVEN FABRIC, FILTER LAMINATE FILTER MATERIAL, FILTER MATERIAL FOR DUST COLLECTOR PLEATED FILTER, DUST COLLECTOR PLEATED FILTER, AND MEDIUM-AIR-VOLUME PULSE-JET TYPE DUST COLLECTOR

摘要

A spun-bonded nonwoven fabric according to the present invention comprises a thermoplastic continuous filament constituted of a high-melting point component and a low-melting point component, and is partially-fused. The spun-bonded nonwoven fabric has a convex portion which is not fused and a concave portion which is fused. The bending resistance of the spun-bonded nonwoven fabric in the MD direction is 20-40 mN inclusive. In a cross section of the nonwoven fabric, a thickness t_A from one surface to another surface of the convex portion, a thickness t_B from one surface to another surface of the concave portion, and respective distances t_C and t_D between the one surface of the convex portion and the one surface of the concave portion (t_C < t_D) have a relationship represented by expressions (1) and (2).