초록
The aim of this study is to develop a mixed polyester latent crimped yarn with excellent bulkiness and stretchability. In order to achieve this goal, the thermal and physical behaviors of yarn obtained from two filaments with different shrinkabilities were investigated under various manufacturing conditions. The partially oriented yarn (POY) exhibited various thermal shrinkages under wet and dry conditions. The fabric hand value is affected by the properties of the POY and by the physical properties of the latent crimped yarns, such as linear density, tenacity, breaking strain, and shrinkage. First, the POY should be spun at speeds in the range of 3,000-3,200 m/min so as to produce a wool-like mixed PET yarn with excellent bulkiness and stretching properties. Second, the manufacturing conditions for the latent crimped yarn should be set as follows: 1) intrinsic viscosity difference between 0.15 and 0.2; 2) setting at $120^{\circ}C$; and 3) a low winding speed and high draw ratio during the spinning process. Finally, the heat roller temperature of the drawing machine should be set between $105-120^{\circ}C$ together under overfeeding conditions in order to obtain the desired wool-like mixed latent crimped yarn that exhibits excellent bulkiness and high stretchability, in accordance with the aim of this procedure.
