Unstreteched polyethylene terephthalate yarn in continuous stretching and false twist texturizing processes
AssigneeHoechst Aktiengesellschaft
InventorsGunther Franz, Karl Heinrich, Herbert Poppe
Life of this patent
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Abstract
In known stretching and false twist texturizing processes for the manufacture of bulked yarn filaments of polyethylene terephthalate or of copolyesters of polyethylene terephthalate containing a preponderant proportion of polyethylene terephthalate structural units which are unstretched but have a degree of preorientation characterized by a natural stretching ratio of from about 1 : 2.7 to about 1 : 1.1 are used. The bulky yarns obtained do not have the high numbers of broken filaments and slubs hitherto observed and are distinguished by a uniformity of titer and an improved uniform dyeability.
Claims4
Improvement in continuous stretching and false twist texturizing processes for the manufacture of voluminous yarns from unstretched spun filaments of polyesters comprising at least preponderantly polyethylene terephthalate structural units, which comprises using unstretched but pre-oriented spun filaments having a degree of pre-orientation characterized by a natural stretching ratio of about 1:2.0 to about 1:1.4, feeding the said filaments to continuously working stretching and false twist texturizing devices, stretching the said yarns at a stretch ratio of about 1:2.3 to about 1:1.7, and winding up the texturized yarns obtained.
Dependencies are inferred from the claim text.