Flat multifilament yarn knitted fabric

A flat multifilament yarn knitted fabric comprising multifilament yarns each comprising a plurality of flat cross section shape-having filaments comprising a fiber-forming thermoplastic polymer as a main component, characterized in that

• three or more expanded portions expanded toward the outside of the longitudinal central line of the flat cross section of the above-described filament per half side of the flat cross section and two or more constricted portions formed between the expanded portions per half side are formed on both the sides of the longitudinal central line, approximately symmetrically with respect to the above-described longitudinal central line, in the flat cross section of the filament;
• cross section flatness represented by the ratio (B/C1) of the length (B) of the above-described modified cross section in the direction of the longitudinal central line to the maximum width (C1) in the direction orthogonal to the direction of the longitudinal central line is in a range of 2 to 6;
• and the above-described multifilament yarns are comprised in the knitted fabric in an amount of 50 to 100 percent by weight based on the total weight of the knitted fabric
• wherein a K value determined by the following expression is not more than 35×103, as the whole of the above-described knitted fabric,
• K=Co×We×(D/1.1)1/2
• wherein Co is the course number (courses/2.54 cm) of the knitted fabric;
• We is the wale number (wales/2.54 cm) of the knitted fabric;
• and D is the average value (dtex) of the total finenesses of the yarns constituting the knitted fabric.