Herbert O Davis

US Patent:

42960584, Oct 20, 1981

Filed:

Oct 23, 1978

Appl. No.:

5/953662

Inventors:

John C. Chen - North Plainfield NJ
Herbert L. Davis - Convent Station NJ

Assignee:

Celanese Corporation - New York NY

International Classification:

D01F 104

US Classification:

264 78

Abstract:

The present invention provides an improvement in a process for providing a dyed, false twist texturized, fibrous material comprising at least 85 mole percent polyethylene terephthalate which is subject to variations in dye uptake induced by the false twist texturizing treatment conducted on said fibrous material prior to or concurrently with a dyeing process by enhancing the uniformity of dye uptake of the fibrous material. The enhancement in the uniformity of dye uptake is achieved by subjecting the fibrous material, which has been previously oriented but prior to false twist texturizing, to an annealing step at a specifically defined temperature for a specifically defined length of time while controlling the length of the fibrous material in a specifically defined manner.

US Patent:

40838293, Apr 11, 1978

Filed:

Apr 20, 1977

Appl. No.:

5/789374

Inventors:

Gordon W. Calundann - North Plainfield NJ
Herbert L. Davis - Convent Station NJ
Frederick J. Gorman - Succasunna NJ
Robert M. Mininni - Charlotte NC

Assignee:

Celanese Corporation - New York NY

International Classification:

C08G 6306
C08G 6318

US Classification:

260 47C

Abstract:

A wholly aromatic polyester is provided which has been found to be highly amenable to melt extrusion to yield high performance fibers. Such fibers following thermal treatment exhibit high tenacity and tensile modulus properties which are well retained at elevated temperatures while exhibiting a low degree of shrinkage. Unlike wholly aromatic polyesters normally encountered in the prior art, the polymer of the present invention is not intractable and may be melt extruded with ease at temperatures below approximately 300. degree. C. , and preferably below approximately 280. degree. C. The aromatic polyester of the present invention consists essentially of recurring units (a) p-oxybenzoyl moiety, (b) 2,6-dicarboxynaphthalene moiety, (c) symmetrical dioxy aryl moiety (as defined), and (d) isophthaloyl moiety and/or metal-dioxy phenylene moiety, and is free of units which possess ring substitution. The wholly aromatic polyester of the present invention forms an atypical thermotropic melt phase which is exhibited in the absence of ring substitution at a relatively low temperature which facilitates fiber formation with ease. The wholly aromatic polyester of the present invention following melt spinning and thermal treatment commonly can exhibit an average single filament tenacity of at least 15 grams per denier, and an average single filament tensile modulus of at least 300 grams per denier.