To provide a wound yarn package and a method for manufacturing the same in which even if sea-island type fibers are wound around a bobbin one by one by a traverse mode, cob-webbing and curling are less likely to occur, and the variation in the heat shrinkage rate between layers constituting the yarn layer is reduced. When winding sea-island type fibers with a fineness of 100 to 6400 dtex around a bobbin one by one by a traverse mode to form a yarn layer, each yarn constituting the n-th yarn layer is wound at a position 0 to x mm away from each yarn constituting the (n1)-th yarn layer, with the yarn width of the sea-island type fiber being taken as x (mm), to fabricate a wound yarn package.

Provided is a melt-anisotropic aromatic polyester multifilament having excellent abrasion resistance. The melt-anisotropic aromatic polyester multifilament has a single fiber fineness from 10 to 80 dtex and comprises 3 to 10 wt % of a dimethylsilicone-series finishing agent applied on a fiber surface of the multifilament, based on the multifilament, the finishing agent containing a dimethylsilicone-series compound having a weight average molecular weight from 15000 to 40000.

Provided is a new and better solution to the problems associated with the premature softening of PLA filaments in the additive manufacturing of three dimensional articles. It is based upon the finding that poly (lactic acid) filaments with high crystallinity offer much better resistance to heat-induced softening. The crystalline poly (lactic acid) filament can accordingly be used in the additive manufacturing of three dimensional articles without encountering the problems associated with premature softening, such as poor quality and printer jamming. The crystalline poly (lactic acid) filaments can also be used in additive manufacturing of three dimensional articles without compromising the quality of the ultimate product, reducing printing speed, increasing cost, or leading to increased printer complexity. It more specifically discloses a filament for use in three-dimensional printing which is comprised of crystalized poly (lactic acid), wherein said filament has a diameter which is within the range of 1.65 mm to 1.85 mm.

This invention involves a new and better solution to the problems associated with the premature softening of PLA filaments in the additive manufacturing of three dimensional articles. It is based upon the finding that poly(lactic acid) filaments with high crystallinity offer much better resistance to heat-induced softening. The crystalline poly(lactic acid) filament of this invention can accordingly be used in the additive manufacturing of three dimensional articles without encountering the problems associated with premature softening, such as poor quality and printer jamming The crystalline poly(lactic acid) filaments of this invention can also be used in additive manufacturing of three dimensional articles without compromising the quality of the ultimate product, reducing printing speed, increasing cost, or leading to increased printer complexity. This invention more specifically discloses a filament for use in three-dimensional printing which is comprised of crystalized poly(lactic acid), wherein said filament has a diameter which is within the range of 1.65 mm to 1.85 mm.