METHOD FOR GENERATING A HALOGEN-STABLE ANTI-MICROBIAL SYNTHETIC FIBER

Abstract

A method for producing fibers with improved color and anti-microbial properties is described. One embodiment includes a method for generating a halogen stable antimicrobial synthetic fiber, the method comprising creating a mixture that includes a polymer, an anti-microbial agent, and a non-halogen pigment, and extruding the mixture to form an anti-microbial synthetic fiber.

Claims

1. A method for generating a halogen-stable anti-microbial synthetic fiber, the method comprising: creating a mixture comprising: a base polymer comprised at least predominantly of polyester in pellet form, an anti-microbial agent that includes silver in metallic form, salt form, or ionic form, a cationic non-halogen pigment that includes halogen bonding sites, and titanium dioxide for softening a hue of the non-halogen pigment; heating the mixture to a melt temperature; and extruding the mixture to form an anti-microbial synthetic fiber; wherein the cationic non-halogen pigment is adapted to attract and bond with halogenic molecules at the halogen bonding sites, thereby shielding the anti-microbial agent from degradation arising from interactions with halogenic molecules.

2. The method of claim 1, wherein the cationic non-halogen pigment comprises an element with known anti-microbial properties.

3. The method of claim 1, wherein the cationic non-halogen pigment is phthalo blue.

4. The method of claim 1, wherein the cationic non-halogen pigment is selected from the group consisting of CaCuSi4O10, HgS, FeO, Na2OSAl2SiO6, BaCuSi2O6, ({CuC2H3O2}2-3Cu(AsO2)2), and CuHA5O5.

5. The method of claim 1, wherein the anti-microbial agent is in a powder form.

6. A method for generating a halogen-stable anti-microbial synthetic fiber, the method comprising: creating a mixture comprising: a base polymer comprised at least predominantly of polyester in pellet form, an anti-microbial agent that includes copper in metallic form, salt form, or ionic form, a cationic non-halogen pigment that includes halogen bonding sites, and titanium dioxide for softening a hue of the non-halogen pigment; heating the mixture to a melt temperature; and extruding the mixture to form an anti-microbial synthetic fiber; wherein the cationic non-halogen pigment is adapted to attract and bond with halogenic molecules at the halogen bonding sites, thereby shielding the anti-microbial agent from degradation arising from interactions with halogenic molecules.

7. The method of claim 6, wherein the cationic non-halogen pigment comprises an element with known anti-microbial properties.

8. The method of claim 6, wherein the cationic non-halogen pigment is phthalo blue.

9. The method of claim 6, wherein the cationic non-halogen pigment is selected from the group consisting of CaCuSi4O10, HgS, FeO, Na2OSAl2SiO6, BaCuSi2O6, ({CuC2H3O2}2-3Cu(AsO2)2), and CuHA5O5.

10. The method of claim 6, wherein the anti-microbial agent is in a powder form.

11. A method for generating a halogen-stable anti-microbial synthetic fiber, the method comprising: creating a mixture comprising: a base polymer comprised at least predominantly of polyester in pellet form, an anti-microbial agent that includes silver and copper in metallic form, salt form, or ionic form, a cationic non-halogen pigment that includes halogen bonding sites, and titanium dioxide for softening a hue of the non-halogen pigment; heating the mixture to a melt temperature; and extruding the mixture to form an anti-microbial synthetic fiber; wherein the cationic non-halogen pigment is adapted to attract and bond with halogenic molecules at the halogen bonding sites, thereby shielding the anti-microbial agent from degradation arising from interactions with halogenic molecules.

12. The method of claim 11, wherein the cationic non-halogen pigment comprises an element with known anti-microbial properties.

13. The method of claim 11, wherein the cationic non-halogen pigment is phthalo blue.

14. The method of claim 11, wherein the cationic non-halogen pigment is selected from the group consisting of CaCuSi4O10, HgS, FeO, Na2OSAl2SiO6, BaCuSi2O6, ({CuC2H3O2}2-3Cu(AsO2)2), and CuHA5O5.

15. The method of claim 11, wherein the anti-microbial agent is in a powder form.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by reference to the following Detailed Description and to the appended claims when taken in conjunction with the accompanying Drawings wherein:

[0012] FIG. 1 includes a flow chart for an exemplary method of producing fibers consistent with an embodiment of the present invention;

[0013] FIG. 2 shows the molecular structure of Phthalo Blue pigment, with the copper molecule at its core;

[0014] FIG. 3 shows the molecular structure of Phthalocyanine Green G pigment with 15 chlorine molecules; and

[0015] FIG. 4 shows the molecular structure of Phthalo Green 36 pigment with a combination of 16 chlorine and bromine molecules.

DETAILED DESCRIPTION

[0016] Referring now to the drawings, where like or similar elements are designated with identical reference numerals throughout the several views, and referring in particular to FIG. 1, it illustrates a method for manufacturing colored fibers with improved anti-microbial performance. At Step 100 a mixture is created, the mixture including a polymer, an anti-microbial alloy powder, and a cationic pigment. As used herein, a polymer refers to a compound suitable for fiber and fabric generation including, but not limited to, a thermoplastic polymer, polyester, nylon, rayon, polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), co-PET, polylactic acid (PLA), and polytrimethylene terephthalate (PTT). In a preferred embodiment, the polymer may be polyester for durability, wrinkle resistance and color retention or nylon for its antidrip, slow burn properties.

[0017] An anti-microbial agent may be any suitable anti-microbial, such as silver, copper, zinc and/or gold in metallic forms (e.g., particulates, alloys and oxides), salts (e.g., sulfates, nitrates, acetates, citrates, and chlorides) and/or in ionic forms. In some embodiments, the anti-microbial agent is an anti-microbial alloy powder with a particle size of less than 1 micron, and preferably 0.3 to 0.6 micron.

[0018] The anti-microbial agent may be comprised of an anti-microbial powder formed from alloys of one or more metals that exhibit anti-microbial properties. Antimicrobial alloys made of two or more element alloys can have superior anti-microbial properties compared to one element particles. Embodiments of the present invention can include an anti-microbial alloy which includes a combination of: transition metals of the periodical table such as chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, and/or gold; rare earth metals from the lanthanides such as cerium, neodymium, samarium, gadolinium, terbium, dysprosium, holmium, and/or erbium; and/or alkali metals such as lithium, sodium, potassium, magnesium, and/or calcium. The combination may comprise a binary combination, ternary combination, quaternary combination, or even higher order combination. The selected alloys, and the relative percentages of each alloy, may be selected depending on the intended use of the fiber or other selection criteria. Different combinations will result in different anti-microbial classes that may be used with the present invention.

[0019] For example, different classes of anti-microbial alloys have been produced by QuarTek Corporation as described in various patent applications (U.S. Provisional Application Nos. 60/888,343 and 60/821,497 filed on Aug. 4, 2006 and U.S. patent application Ser. No. 11/868,475 filed on Oct. 06, 2007, Ser. No. 11/858,157 filled on Sep. 20, 2007, and Ser. No. 11/671,675 filed on Feb. 6, 2007). These anti-microbial alloys have been produced by varying the elemental composition of the alloys, the elemental ratios within the same alloy, or by changing parameters in the synthesis process. As needed, these anti-microbial alloys may be synthesized in various size ranges from 5 nm to 2000 nm, preferably less than 1000 nm, or even within the range of 100-500 nm.

[0020] A cationic pigment is a pigment which has a positively charged molecular structure. In a preferred embodiment, the cationic pigment is a non-halogen pigment which does not include halogens such as chlorine, bromine or fluorine in its molecular structure. In another embodiment, the cationic pigment further includes halogen bonding sites that can attract chlorine or other halogens that may come into contact with the fiber, such as during laundering. These halogen bonding sites can attract and connect to a chlorine molecule or other halogen molecules and protect the alloys of copper, silver, gold, and/or zinc that provide the anti-microbial properties to the fiber. In yet further embodiments, the cationic pigment may be selected because it comprises an element with known anti-microbial properties.

[0021] For example, a preferred cationic pigment is Phthalo Blue Pigment (Phthalocyanine Blue), which has a molecular structure C.sub.32H.sub.16CuN.sub.8 as shown in FIG. 2. Phthalo Blue was chosen because, as shown in FIG. 2, it does not include a halogen, contains a Copper molecule in its core, and has 16 available sites that can attract halogen molecules such as chlorine. A halogen molecule such as chlorine can replace a hydrogen molecule and protect the alloys of copper, silver, gold, and zinc. In addition, Phthalo Blue is a brilliant blue pigment which resists fading due to bleach and sunlight. It has excellent hiding power and prevents any discoloration from the oxidation of copper, silver, or zinc. In some embodiments, Titanium Dioxide may also be added because it has excellent hiding power and softens the strong blue of Phthalo Blue. Titanium Dioxide also does not contain any chlorine molecules.

[0022] Other non-halogen pigments that may be selected include:

[0023] Egyptian Blue (Calcium Copper Silicate) CaCuS.sub.14O.sub.10

[0024] Vermillion (Mercury Sulfide) HgS

[0025] Iron Oxide Red FeO

[0026] Ultramarine Blue Na.sub.2OSAl.sub.2SiO.sub.6

[0027] Han Purple BaCuSi.sub.2O.sub.6

[0028] Paris Green (Aceto-arsenite) ({CuC.sub.2H.sub.3O.sub.2}.sub.2-3 Cu(AsO.sub.2).sub.2)

[0029] Sheele's Green (Copper Arsenite) CuHA.sub.5O.sub.5

[0030] As indicated by Step 200 in FIG. 1, once the mixture is created, the mixture may be extruded in order to create a fiber. The extrusion process itself depends on the temperature of the mixture being sufficiently high to melt the mixture. A melting step may be a separate step in FIG. 1 or it may be part of either the mixing process or the extruding process. When the mixture is at a sufficiently high temperature, the mixture may be extruded using conventional mechanisms such as a spinneret. The fiber may then be drawn, crimped, cut and spun into a yarn or other fabric depending on the intended end use (Step 300).

[0031] An exemplary fiber consistent with the present invention was made with between 99.3% and 99.6% Polyester (PET) resin, between 0.1% and 0.4% QuarTek Alloy QSM-ACL73 and 0.3% Phthalo Blue pigment. In some embodiments, Titanium Dioxide may also be added. The compounds were extruded at a melt temperature of 290 C. and pumped through a 2400 hole spinneret to produce a fiber of 5.5 denier. The fiber was then drawn to 1.5 denier, crimped, and cut to 1.5 (38 mm). These exemplary fibers exhibit improved visual properties and improved anti-microbial effectiveness after launderings. Fibers produced with these pigments had very poor anti-microbial properties.

[0032] In accordance with the present method, pigments such as Phthalocyanine Green G (molecular structure is shown in FIG. 3) and Phthalo Green 36 (molecular structure is shown in FIG. 4) will not be used because they contain chlorine molecules which adversely affect the anti-microbial properties of a resultant fiber.

[0033] In conclusion, the present invention provides, among other things, method for producing fibers with improved color and anti-microbial properties. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims.