The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 1992
Filed:
Sep. 11, 1990
Unitika, Osaka, JP;
Abstract
(1) Polyester fiber which consists substantially of polyethylene terephthalate, the fiber being characterized by strength of least 7.0 g/d, initial Young's modulus of at least 85 g/d, elongation of less that 20%, degree of crystallization X.rho. of at least 45% and the ratio of birefringence (.DELTA.n) and the degree of crystallization X.rho. from 0.38 to 0.45. (2) Method of making polyester fiber, characterized as follows: Polyethylene terephthalate is melt spun then passed through the heated cylinder which is installed directly under the spinning die; cooled and solidified; the oil agent is imparted and the yarn is taken-up at the speed of over 2000 m/min; this is drawn to a ratio of 1.5-2.3 in at least 2-drawing stages in continuation; then heat treated; the surface temperature of the drawing rollers at the final drawing stage is kept at 220.degree.-250.degree. C.; a non-contact type heating plate heated to a surface temperature of 250.degree.-500.degree. C. is installed 200-100 mm apart from the yarn at the final drawing stage to heat the drawn yarn; the yarn is heat treated again by the heating roller and finally wound-up.