The Impact of Miss Stitch on the Dimensional Properties and Stability of Double Weft Knitted Fabrics after Dry and Washing Relaxations

This study investigated the effect of the rib set-out repeat and single miss stitches on the structural properties and dimensional stability of double weft knitted fabrics compared with half Milano rib. Nine variations of double weft knitted fabrics were produced, each with a different number of inactive needles at the width repeat Rb. The fabrics were tested after 10 days of dry relaxation and five washings. The fabric’s structural repeat at the height Rh consisted of a combination of two courses, rib and plain (variant 1), and rib set-out and single with miss (float) stitch, with stitch repeats varying at the width Rb (for variants 2–10). The miss stitch was made on the technical back of the knitted fabrics, and the number of inactive needles during the production of the single and double stitches ranged from 1 to 3. The fabrics were manufactured using a 10-gauge flat bed-knitting machine from blended wool/PAN (60% wool, 40% PAN) 25×2tex×2 yarn. The results demonstrated that the width repeat of miss knit stitches Rb (different numbers of knit and miss loop stitches) plays a crucial role in determining the dimensional stability and structural properties of double knitted fabrics. The number of washing cycles did not significantly impact the structural properties (around ±5%). The research results demonstrated shrinkage in the length and width directions, specifically after the first two washing cycles. The rib set-out repeat and single miss stitches affect dimensional changes in both directions: an increase in the number of inactive needles increases shrinkage in the length and decreases shrinkage in the width direction. Overall, this study highlights the importance of the number and placement of miss stitches during the design process of double weft knitted fabrics, particularly when aiming to achieve specific structural and dimensional properties.