Annealed polyester filaments and a process for making them
AssigneeE. I. Du Pont de Nemours and Company
InventorsJack A. Hancock, Walter D. Johnson, Alan D. Kennedy
Life of this patent
Estimating the term…
Abstract
A process for annealing drawn polyester filaments with saturated steam of at least about 150 psig provides products with a novel fine structure that results in an improved balance of strength, dyeability, shrinkage, crimpability and trimer in the product.
Claims16
A crimped filament of poly(ethylene terephthalate) having at least 93% by weight of dioxyethylene and terephthaloyl radicals repeating units and having an improved balance of dyeability and tensile properties which comprise a T.sub.7 of at least 1.5 gpd, a T+T.sub.7 of at least 7 gpd and less than about 10 gpd, wherein T is the tenacity at break elongation and T.sub.7 is the tenacity at 7% elongation, a dry heat shrinkage at 196.degree. C. of less than about 10%, a dyeability/orientation relationship characterized by a "D" number of less than about 3.8 and greater than about 1.8, a surface cyclic trimer content as defined by a "T" number of less than about 20, and a relative viscosity of less than 25.
A crimped filament of poly(ethylene terephthalate) comprised of at least 93% by weight of dioxyethylene and terephthaloyl radicals and no more than 0.3% radicals with ionic dye sites and containing at least 3% of other neutral radicals, the filament having an improved balance of dyeability and tensile properties comprising a T.sub.7 of greater than 1.1 gpd, a T+T.sub.7 of greater than 5 gpd and less than 7 gpd, wherein T is the tenacity at break elongation and T.sub.7 is the tenacity at 7% elongation, a dry heat shrinkage at 196.degree. C. of less than about 10%, a "D" number of less than 3.8 and greater than about 1.8, a trimer "T" number of less than about 20 and a RDDR dye rate of at least 0.12.
A crimped filament of poly(ethylene terepthlate) comprised of at least 93% by weight of dioxyethylene and terephthaloyl radicals, at least 1.3% of aromatic radicals containing an ionic dye site and up to about 4% of neutral organic radicals, the filament having an improved balance of dyeability and tensile properties comprising a T.sub.7 of greater than 1.2 gpd, a T+T.sub.7 greater than about 5.0 gpd and less than 7.0 gpd, wherein T is the tenacity at break elongation and T.sub.7 is the tenacity at 7% elongation, a dry heat shrinkage at 196.degree. C. of less than about 10%, a "D" number of less than about 3.8 and greater than about 1.8 and a trimer "T" number of less than about 20.
Dependencies are inferred from the claim text.