Abstract: The invention is a method of producing a polyester filament which has a superior combination of tensile, dyeability and shrinkage properties. The method comprises forming a polyester copolymer from a mixture consisting essentially of terephthalic acid (TA) or dimethyl terephthalate (DMT), ethylene glycol, adipic acid, and pentaerythritol wherein the adipic acid is added in an amount of between 1.3 and 3.2 weight percent of the terephthalic acid and pentaerythritol is added in the amount from 175 to 700 ppm by weight of terephthalic acid; forming the filament from the copolymer, drawing the copolymer filament, and heat-setting the drawn filament. The invention also comprises the enhanced fiber formed by the process having an atmospheric dyeability greater than that of an unenhanced PET produced under identical conditions except for the addition of the adipic acid and pentaerythritol, a modulus of greater than 3.0 g/denier, a tenacity from about 5 to 7 g/denier and a hot air shrinkage of less than 10%.

Abstract: The invention is a polyester and a method for producing a polyester filament which has a combination of flame resistance and low pilling properties. The method comprises forming a polyester polymer from a mixture consisting essentially of terephthalate acid or dimethyl terephthalate, ethylene glycol, a chain branching agent having a functionality of at least 3 and a phosphinic acid in the amount between 0.5 and 20 mole percent of the terephthalate acid and monomer. In particular, the invention also comprises the enhanced fiber formed by the process, as well as the fabrics having a pilling of about 3 to less than 5 as measured in accordance with ASTM D-3512-82.

Abstract: The invention is a polyester and a method for producing a polyester fiber which has a combination of flame resistance and low pilling properties. The method comprises forming a polyester fiber made from a blend of two polyester polymers, one polyester polymer containing an oxysilicon compound and the second polyester polymer containing pentaerythritol and a phosphinic acid in the amount between 0.5 and 20 mole percent of the terephthalate acid and monomer. In particular, the invention also comprises the enhanced fiber formed by the process, as well as the fabrics having a pilling of about 3 to less than 5 as measured in accordance with ASTM D-3512-82.

Abstract: The invention is a method of producing a polyester filament which has a superior combination of tensile, dyeability and shrinkage properties. The method comprises forming a polyester copolymer from a mixture consisting essentially of terephthalic acid (TA) or dimethyl terephthalate (DMT), ethylene glycol, adipic acid, and pentaerythritol wherein the adipic acid is added in an amount of between 1.3 and 3.2 weight percent of the terephthalic acid and pentaerythritol is added in the amount from 175 to 700 ppm by weight of terephthatlic acid; forming the filament from the copolymer, drawing the copolymer filament, and heat-setting the drawn filament. The invention also comprises the enhanced fiber formed by the process having an atmospheric dyeability greater than that of an unenhanced PET produced under identical conditions except for the addition of the adipic acid and pentaerythritol, a modulus of greater than 3.0 g/denier, a tenacity from about 5 to 7 g/denier and a hot air shrinkage of less than 10%.