Title
Effect of rib set-out repeat and needle inactivity on structural and stretch behavior of flax-containing double-knitted fabrics
Authors
NADIIA P. BUKHONKA

Received September 30, 2025
Published Volume 60 Issue 3-4 March-April
Keywords flax, double-knit, miss (float) stitches, rib set-out repeat, inactive needle, shrinkage, stretch properties

Abstract
This study investigates the structural and stretch properties of five variants of double-knit fabrics made from 29 × 2 tex flax-containing (50% PAN, 27% viscose, and 23% flax) yarn in comparison with a half Milano rib structure. These fabrics are knitted with alternating rib set-out and plain courses. The effect of 1–3 inactive needles (X) in the rib-set out repeat on the back bed of a 10-gauge flat-bed knitting machine was assessed, while plain stitch was knitted on the front bed of the knitting machine. The results showed that lengthwise dimensional changes were greater than widthwise changes, with the most notable effects occurring after the first washing cycle. Adding inactive needles reduced lengthwise shrinkage, balanced widthwise changes, and enhanced overall dimensional stability. Increasing the number of inactive needles reduced the number of wales and courses, resulting in lower stitch density, while stitch length remained at a similar level, and fabric thickness and weight decreased, indicating controlled adjustment of fabric compactness. Stretch analysis showed that elastic deformation dominates, with delayed and residual deformations playing secondary roles. Fabrics with inactive needles exhibited reduced lengthwise deformation, but reduced widthwise stability, highlighting the importance of the rib-set out repeat. These findings offer practical guidance for optimizing double-knit fabric structure, dimensional stability, and stretch performance in various knitted fabric applications.