This study aims to optimize the production of inject yarn by modifying spinning geometry and to evaluate how these path variations influence both yarn quality and aesthetic characteristics.
A 20 Ne inject yarn containing 86% cotton and 14% dope-dyed polyester was produced using ring spinning under three yarn path conditions: left offset, right offset and straight. The yarns were assessed for mass variation, imperfections, hairiness, strength, elongation, splice strength and fiber distribution.
The straight yarn path exhibited improved evenness, reduced hairiness and a lower number of imperfections owing to more stable ballooning and uniform twist insertion. In contrast, offset paths, particularly the left offset, increased unevenness and hairiness due to tension asymmetry. However, mechanical performance improved under the right offset showing the best results in terms of CSP, tenacity, elongation and splice strength. Microscopic observation also revealed better surface visibility of injected polyester fibers in the offset configurations.
This study demonstrates that spinning geometry adjustment is a practical and effective approach for balancing the structural performance and visual appearance of inject yarns. The findings highlight the right-offset path as the most promising configuration for achieving an improved combination of yarn quality, strength and injected fiber visibility.
