The following conclusions have been drawn from the above studies: The tenacity and breaking extension of DREF-III yarn increases significantly with increase in core content from 50% to 60% and thereafter decreases. The tenacity and breaking extension also increases with increase in level of spin finish from 0.2% to 0.4% and thereafter decreases insignificantly. 1. When the proportion of wrapper fibre increases from 30% to 40%, the subsequent result is a significant increase in abrasion resistance. The latter however dimin- ishes as the proportion of wrapper fibre further increases to 50%. Yarn abrasion resistance gradually decreases as the level of spin finish increases from 0.2% to 0.6%. 2. Irrespective of add-on spin finish level, the additional twist required to break the yarn increases significantly with the increase in percentage of core content from 50% to 60%, and thereafter decreases. The apparent yarn twist increases with increase in level of spin finish from 0.2% to 0.4%; thereafter it shows a decreasing trend. 3. Yarn diameter increases gradually when the proportion of sheath fibres increases from 30% to 50%. However it shows a decreasing trend when the level of spin finish increases from 0.2% to 0.4%, and thereafter shows an increasing trend. 4. Higher yarn unevenness and imperfections have been observed for 50% sheath, and improve as the sheath content decreases to 30%. The yarn unevenness and imperfections also increase with increase in level of spin finish from 0.2% to 0.6%. 5. Flexural rigidity is significantly affected by the core sheath ratio and level of spin finish. The lowest flexural rigidity has been observed at 50/50 core sheath ratio and 0.4% level of fibre finish.
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