Colored aramid fibers

Claim 2

High strength, high modulus p-aramid fibers characterized in that they contain 0.01 to 6% by weight of a completely organic pigment distributed uniformly throughout the fibers and having no particles or agglomerates larger than 0.01 microns.

Claim 3

The fibers of Claim 1 characterized in that the p-aramid is poly( p -phenylene terephthalamide).

Claim 4

The fibers of Claim 1 characterized in that the organic pigment is selected from the group consisting of (1) monoazo and disazo pigments, (2) anthanthrone pigments, (3) indanthrone pigments, (4) pyranthrone pigments (5) vilanthrone pigments, (6) flavanthrone pigments, (7) quinacridone pigments, (8) dioxazine pigments, (9) indigoid and thioindigoid pigments and (10) isoindolinone pigments.

Claim 5

The fibers of Claim 2 characterized in that the organic pigment is selected from the group consisting of (1) monoazo and disazo pigments, (2) anthanthrone pigments, (3) indanthrone pigments, (4) pyranthrone pigments (5) vilanthrone pigments, (6) flavanthrone pigments, (7) quinacridone pigments, (8) dioxazine pigments, (9) indigoid and thioindigoid pigments and (10) isoindolinone pigments.

Claim 6

The fiber of Claim 1 characterized in that the organic pigment is selected from the group consisting of Colour Index Pigment Red 3 and Colour Index Pigment Red 242.

Claim 7

The fibers of Claim 1 characterized in that the organic pigment is Colour Index Pigment Blue 60, Colour Index Pigment Orange 40, Colour Index Pigment Blue 65, Colour Index Pigment Yellow 24, Colour Index Pigment Red 122, Colour Index Pigment Violet 23, Colour Index Pigment Red 88, Colour Index Pigment Red 86 or Colour Index Pigment Yellow 173.

Claim 8

A process for preparation of high strength, high modulus p-aramid fibers comprising the steps of: a) agitating a mixture of: i) sulfuric acid having a concentration of at least 98%; ii) p-aramid polymer having an inherent viscosity of at least 4 in an amount which is at least 18 weight percent of the mixture; and iii) completely organic, sulfuric acid soluble, pigment in an amount which is from 0.01 to 6 weight percent based on the p-aramid polymer; b) heating the mixture with continued agitation to a temperature of 80 to 105°C to form a uniform solution; c) extruding the solution through a spinneret; d) drawing the extruded solution through a non-coagulating fluid layer 0.5 to 2.5 centimeters thick and stretching the extruded solution 3 to 10 times its original length in the non-coagulating layer; e) passing the stretched solution into and through an aqueous coagulating bath having a temperature of -5 to 25°C to form filaments; and f) washing the filaments with water and/or dilute aqueous alkali.

Claim 9

A process for preparation of high strength, high modulus p-aramid fibers comprising the steps of: a) agitating a mixture of: i) sulfuric acid having a concentration of at least 98%; ii) p-aramid polymer having an inherent viscosity of at least 4 in an amount which is at least 18 weight percent of the mixture; and iii) completely organic, sulfuric acid soluble, pigment in an amount which is from 0.01 to 6 weight percent based on the p-aramid polymer; b) heating the mixture with continued agitation to a temperature of 80 to 105°C to form a uniform solution; c) extruding the solution through a spinneret; d) drawing the extruded solution through a non-coagulating fluid layer 0.5 to 2.5 centimeters thick and stretching the extruded solution 3 to 10 times its original length in the non-coagulating layer; e) passing the stretched solution into and through an aqueous coagulating bath having a temperature of -5 to 25°C to form filaments; and f) washing the filaments with water and/or dilute aqueous alkali.

Claim 10

Process of Claim 7 wherein the p-aramid is poly( p -phenylene terephthalamide).

Claim 11

Process of Claim 7 characterized in that the organic pigment is selected from the group consisting of (1) monoazo or disazo pigments, (2) anthraquinone type pigments, (3) indanthrone pigments, (4) pyranthrone pigments (5) vilanthrone pigments, (6) flavanthrone pigments, (7) quinacridone pigments, (8) dioxazine pigments, (9) indigoid and thioindigoid pigments and (10) isoindolinone pigments.