Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3803453 A
Publication typeGrant
Publication date9 Apr 1974
Filing date19 Jun 1973
Priority date21 Jul 1972
Also published asCA1019127A1, DE2337103A1, DE2337103B2, DE2337103C3
Publication numberUS 3803453 A, US 3803453A, US-A-3803453, US3803453 A, US3803453A
InventorsD Hull
Original AssigneeDu Pont
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Synthetic filament having antistatic properties
US 3803453 A
Images(1)
Previous page
Next page
Description  (OCR text may contain errors)

United States Patent 1 1 p 11 1 3,803,453

Hull Apr. 9, 1974 SYNTHETIC FILAMENT HAVING ANTISTATIC PROPERTIES [56] References Cited [75] Inventor: I Donald Robert Hull, Wilmington, UNITED STATES PATENTS I 3,678,675 7/1972 Klein 317/2 C 7 Assigneez E L du p m d Nemours and 3,639,807 2/1972 McCune 1. 317/2 C 3,582,445 6/1971 Okuhashi.... 57/157 AS Company wllmmgton 3,551,279 12/1970 Ando et al. 161/175 [22] Filed: June 19, 1973 [2]] App]. No.: 371,507 Primary Examiner-J. D. Miller Assistant Examiner-Harry E. Moose, .lr. Related U.S. Apphcation Data 63 Continuation-inart of Ser. No. 273,793, Jul 21, 1 1972, abandoned y [57] ABSTRACT Novel synthetic filament having antistatic properties 317/2 57/157 6 comprising a continuous nonconducting sheath of syn- 161/175, 317/2 C, 139/426 R thetic polymer surrounding a conductive polymeric 51] Int. Cl. 05f 3/00 ore containing carbon black, [58] Field of Search I. 317/2 R, 2 C; l6l/l75;

5 /1 7 AS 20 Clalms, 2 Drawmg Flgures 1 SYNTHETIC F ILAMENT HAVING ANTISTATIC PROPERTIES CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application Ser. No. 273,793 filed July 21, 1972 now abandoned.

BACKGROUND OF THE INVENTION 3,639,807; such wire in the face yarn tends to lose effectiveness as it bends and becomes pressed down into the carpet.

SUMMARY OF THE INVENTION This invention provides a novel synthetic filament having antistatic properties comprising a continuous nonconductive sheath of a synthetic, thermoplastic, fiber-forming polymer surrounding an electrically conductive core comprised of electrically conductive carbon black dispersed in a thermoplastic, synthetic polymer, said sheath comprising at least 50 percent of the filament cross-sectional area (i.e., at least 50 percentby volume) and said filament core having an electrical resistance of less than ohms per inch at a direct current potential of 2 kilovolts. For use'at low concentrations in admixture with other filaments, the filaments of the invention preferably have a core resistance of less than 10 ohms/inch at a direct current potential of 2 kilovolts. Preferably, said filaments have a molecularly oriented sheath as the result of attenuation during spinning and/or drawing in the course of their preparation.

Highly conductive core compositions, i.e., those containing more than percent by weight of said carbon black are preferably employed in filaments having a sheath content of at least 80 percent.

The present invention permits antistatic filaments which may be used in light-colored textile goods. For such end-uses the sheath comprises at least 90 percent of the filament and the sheath is delustered to partially conceal the black core such that the filament has a light reflectance value as described herein of greater than 20 percent. A preferred delustered filament contains 2 to 7 percent by weight of titanium dioxide pigment in the sheath.

By appropriate selection of the sheath polymer, antistatic fibers of this invention may be dyed as desired, cobulked under a variety of conditions and employed in end uses where sheath toughness comes into play. The fibers of this invention avoid the dangers of too high electrical conductivity. They also possess a high level of crush-resistance as compared with for antistatic purposes.

Surprisingly, in spite of the fact that a major portion of the filament consists of the nonconducting sheath whichacts as electrical insulation, the filaments of this invention can be effectively employed for antistatic protection independent of relative humidity as a very minor component of a fabric, yarn or other textile material comprised predominantly of other synthetic fibers or filaments needing antistatic protection. Accordingly, the invention also comprehends antistatic yarn and staple fibers comprised of a mixture of nonconducting synthetic filaments and less than 20 percent by weight of the mixture of filaments of the invention described heretofore. Concentrations of filaments of the invention in such mixtures can provide excellent antistatic performance even when present at concentrations of less than 2 percent, but preferably the mixtures contain at least about 0.05 percent by weight of wire used said filaments. In such mixtures the sheath polymer may be mutually dyeable with the nonconducting filaments; more specifically, it may be of the same polymeric class or genus as the polymer of the nonconducting filaments, e.g., nylon sheath fiber with nylon homofiber.

The invention is also directed to a process for the preparation of cospun antistatic filaments comprising the steps of cospinning in a sheath/core filament configuration an electrically conductive core composition comprised of an electrically conductive carbon black dispersed in a thermoplastic synthetic polymer surrounded by a nonconductive sheath composition of a synthetic, thermoplastic, fiber-forming polymer, said composition being spun in such proportion that said sheath composition comprises at least 50 percent by volume of said filaments.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a sheathcore filament of the invention.

FIG. 2 is a schematic cross-sectional view of an antistatic yarn comprised of a mixture of filaments of the type depicted in FIG. 1 and nonconducting, synthetic filaments.

In the filament cross-section 5 depicted in FIG. 1, the core material 1 comprises a conductive composition of carbon black 3 dispersed in a polymer matrix 4 surrounded by a sheath material 2 comprising a nonconducting polymer.

In FIG. 2, filaments of cross-section 5 of the type of FIG. 1 are among the substantially greater number of nonconducting synthetic filaments 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The nonconductive sheath" of the filaments of the invention is comprised of a synthetic, fiber-forming polymer. The filaments have a surface filament resistance that is greater than 10 ohms per inch as measured by contacting the subject filament surfaces at low direct current voltages, e.g., of volts or less. Homofibers of such sheath materials would also have resistances greater than 10 ohms per inch measured accordingly. The term fiber-forming is used in the conventional sense to denote linear, high molecular weight polymers which can be formed into fibers of sufficient strength and toughness to be useful.

Compared to the high resistance, nonconductive sheath, the core of the filaments will have a low resistance and high electrical conductivity once electrical contact therewith is established either by the use of electrodes which penetrate the sheath and directly contact the core or by the use of surface contacting electrodes and the application of a sufficiently high voltage to electrically break down the sheath and thereby establish electrical contact with the core. With regard to the latter, i.e., the use of surface contacting electrodes, as an applied DC voltage is increased to several hundred and particularly several thousand volts, a point will occur at which a noted or sudden increase in current will begin to flow as described in the test procedure herein. Once conductivity has been established in this way, the current usually continues to flow even when the voltage is reduced to a lower level, provided filament contact with the electrodes of the measuring device is not altered.

The low resistance properties exhibited by the core of these filaments is evidence that the core maintains its electrical continuity throughout the length of the filament being measured. Breaks in the core continuity between the measuring electrodes are evidenced by a much higher electrical resistance approaching that of the sheath. Occasional breaks in core continuity are found not to be significantly detrimental to the antistatic performance of the filaments of this invention. Preferably, however, the'core remains continuous throughout the entire length of the fibers and filaments of the invention whether they be staple or continuous filaments. It is essential that the core remain continuous for a sufficiently long length along the filament to establish an effective antistatic network in combination with other such antistatic filaments. Filaments having the specified degree of core conductivity when tested by the methods described herein are found to provide highly effective antistatic protection. The filamentsheath may consist of any extrudable, synthetic, thermoplastic, fiber-forming polymer or copolymer. This includes the polyolefins, such as the polyethylenes and the polypropylenes, polyacrylics, polyamides and polyesters of fiber-forming molecular weight. Particularly suitable sheath polymers are the condensationpolyamides of diamines and dicarboxylic acids and those of amino acids; the condensation polyesters, particularly those of terephthalic or isophthalic acids and lower glycols such as ethylene glycol, tetramethylene glycol and hexahydro-p-xylene' diol; and the poly(acrylonitriles). Such polymers may be modified as to their dye receptivities as is known in the art, e.g., by copolymerization to incorporate basic or acidic dye sites, to facilitate their blending and mutual dyeing with other dyed or dyeable synthetic fibers.

Tensile and other physical properties of the filaments of the invention are primarily dependent on the sheath polymer. For high strength filaments, polymers of higher molecular weight and those permitting higher draw ratios are used in the sheath. While undrawn filaments of the invention may provide adequate strength for some purposes, the drawn filaments are preferred.

The sheath thickness must be sufficient to provide the desired protection to the core, e.g., strength and heat and abrasion resistance as well as to assist in visu ally hiding the core where this is important. In general, a sheath thickness of at least 3 microns is desired, with greater thicknesses being governed by the filament denier or diameter which can be used. Suitable sheath thicknesses for normal textile deniers are in the range of 8 to 22 microns. In some applications, for example where the filaments of the invention are to be subjected to high temperature processing with other filaments such as in hot fluid jet bulking or other texturing operations, it is essential that the sheath have a sufficiently high melting point to avoid undue softening or melting under such conditions. For such applications,a higher melting sheath polymer such as poly(hexamethylene adipamide) is preferred over poly(e -caproamide).

The filament core consists of a conducting carbon black dispersed in a polymeric, thermoplastic matrix material. The core material is selected with primary consideration for conductivity and processability. Carbon black concentrations in the core of 15 to 50 percent may be employed. It is found that 20 to 35 percent provides the preferred level of high conductivity while retaining a reasonable level of processability. The use of known, specially prepared more highly conducting carbon blacks are helpful in minimizing the amount required.

Due to the tendency of high loadings of carbon black to reinforce or stiffen plastic compositions, for preparation purposes the softer, lower melting (also lower second order transition temperature) polymeric core matrix materials are preferred to stiffer higher melting ones. The core polymer is preferably lower melting than the sheath polymer with a lower second order transition temperature than that of the sheath. It is, not essential that the core composition be capable of being spun into filaments by itself and therefore the core polymer need not be fiber-forming. The core polymer should be thermally stable and extrudable under the conditions required for spinning the sheath polymer. Suitable core matrix polymers include those selected from the polyamides, polyesters, polyacrylics, polyethers, polycaprolactone, and polyolefins (e.g., polypropylene, low and high density polyethylenes). The polymers may be blended with other materials such as oils and waxes to facilitate processing. Copolymers may also be employed such as poly(ethylene/vinyl acetate) copolymers.

The carbon black may be dispersed in the core polymer by known mixing techniques. Care must be exercised to avoid overmixing and consequent loss in conductivity while still achieving a sufficiently uniform dispersion of carbon black in the core polymer to permit extrusion and spinning. Carbon black containing compositions useful for forming the core in spinning of the filaments of the invention preferably will have a specific resistance of less than 200 ohm-centimeters, and more preferably less than 50 ohm-centimeters.

For satisfactory spinning it is important to remove volatile material from polymers into which the carbon black has been added, prior to melt spinningyThis may be done during or after compounding the carbon black with the polymeric matrix material. It can be helpful to vacuum dry such polymers for example for 16 hours under slight vacuum at 68C. Standard precautions to prevent oxidative degradation during spinning such as the exclusion of oxygen with inert gas in polymer lines, etc. are employed.

The cross-sectional area (which relates directly to filament volume) of the conductive core in the composite filament need only be sufficient to impart the desired resistance properties thereto and may be as low as 0.5 percent by volume. The lower limit is governed primarily by the capability of manufacturing sheath/core filaments of sufficiently uniform quality while maintaining adequate core continuity at the low core volume levels.

Spinning of the filaments of the invention can be accomplished by conventional two-polymer sheath/core spinning equipment with appropriate considerations for the differing properties of the two components. They are readily prepared by known spinning techniques and with polymers as taught for example in US. Pat. Nos. 2,936,482. 2,989,798 contains additional teaching of such spinning with polyamides.

Conventional drawing processes for the filaments can be used but care should be exercised to avoid sharp corners which would tend to break or damage the core. In general, hot drawing, i.e., where some auxiliary filament heating is employed during drawing, is preferred. This tends to soften the core material further and aid drawing of the filaments. These antistatic filaments may be plied with conventional synthetic, undrawn filaments and codrawn.

The subject filaments are readily prepared having a tenacity of at least 1.5 grams per denier, which is quite adequate when said filaments are blended as a minor component with other filaments. The subject filaments preferably have an elongation-at-break of at least percent and less than 150 percent. The resulting textile properties are dependent primarily upon the properties of the other filaments of the blend.

For general applications the filaments of this invention have a denier per filament( dpf) of less than 50 and preferably less than 25 dpf.

The filaments may be of round or non-round, eccentric or concentric sheath/core configurations and combinations thereof. The concentric configuration provides maximum protection and hiding of the core. The fineness of the core greatly aids in its concealment, and the filaments with fine cores can be employed in dyed or patterned textile goods with no other concealing factor. Further concealment where needed is realized by the presence of an opacifier such as voids or a white, solid, particulate delusterant such as titanium dioxide pigment in the sheath. Non-round filament configurations, e.g., multilobal, tend to further conceal the core.

Among variables which affect concealment of the core are sheath thickness and dyeability, sheath/core ratio,'concentration of delustrant such as titanium dioxide in the sheath, and also voids formed by separation of the sheath and core which is found in oriented filament having dissimilar sheath and core polymers, such as a polyamide sheath anda polyethylene core.

Without a concealing sheath to hide the blackness, carbon black filled fibers generally have a light reflectance of less than 5 percent. Reflectance levels above about 20 percent, which can be achieved with this invention, provide a very significant improvement in avoiding coloration problems from the subject filaments in lightly dyed goods.

The filamentsof this invention are capable of providing excellent antistatic protection in all types of textile end uses including knitted, tufted, woven and nonwoven textiles. They may contain conventional additives and stabilizers such as dyes and antioxidants. They may be subjected to all types of textile processing including DESCRIPTION OF THE TEST PROCEDURES Filament Core Resistance Filament core resistance is determined from current flow measured at 2 kilovolts on a 2-inch sample length. Suitable apparatus is a 15 KV Biddle Dielectric Tester (James G. Biddle Company, Plymouth Meeting, Pennsylvania). A three filament bundle is clamped straight between pairs of electrodes 2 inches apart and a sufficiently high voltage is applied to achieve current flow (e.g., 1-4 KV). When current flows, the voltage is adjusted to 2 KV and the yarn resistance is calculated from the current flow according to Ohms Law where R E/l. For example, if at 2 KV the current flow is 10 microamps for the 2-inch sample, the resistance for the three filaments is 10 ohm/inch. Resistance per filament is then'3 X 10 ohms/in. To achieve current flow as above, the voltage should be increased gradually to avoid a sudden current surge which may burn out the filaments. Burn-out is readily detected visually by broken or fused or charred filaments) and such samples should be disregarded. The resistance of filaments of lengths less than 2 inches can be measured by appropriately adjusting the distance between the electrodes.

Reflectance Light reflectance, the lightness or whiteness of the specimen as compared to a magnesium oxide standard, is measured using a pnotoelectric reflection meter. A suitable apparatus is the Photoelectric Reflection Meter Model 610 with a green tristimulus filter Catalog No. 6130), Search Unit Model 610-Y and a white enamel working standard calibrated having a -75 percent reflectance (Catalog No. 6162), obtainable from the Photovolt Corp., Madison Avenue, New York, New York 10016. The conductive filament sample to be measured is wound on 2-inch by 3-inch black mirror cards (approximately six layers of filaments) and the reflectance is measured from the cards (average of 10 measurements).

Percent Core in the Filament Percent core by volume is most conveniently determined by comparing the cross-sectional area of the black core to the total filament by measuring under a microscope. This is conveniently done at a magnification of about 400x. For round filaments this can readily be calculated from the ratio of the square of the core diameter to the square of the total filament diameter. The average of 10 determinations is used to compensate for irregularities. For nonround cross-sections, measurements taken on photographs of filament crosssections at a known magnification permit ready calculation.

Where the sheath polymer is sufficiently different in solution properties from the core that it can be removed by differential solvent action, the percent core material can be determined gravimetrically by dissolving the sheath and comparing the weight of the insoluble core to the weight of the original sample. For example, formic acid can be used to dissolve a 66-nylon sheath from a polyethylene core.

Specific Resistivity Test of Core Material The specific resistance of the core material containing carbon black is determined by measuring the DC. resistance across a two-inch length of a film strip of the sample 1 inch wide, and having a thickness of about 0.01 inch. Such films are conveniently prepared by pressing a powder or pelletized sample of the core material between two sheets of aluminum foil in a press, heated above the melting point under a pressure of 20,000 psig. for 1 to 2 minutes. After cooling, the foil is siripp'eariam the saniiilfilm' and 1-inch wide strips about 2.5-3 inches long are cut from the sample. The

. thickness of the film is measured with a micrometer. A

strip is clamped between two copper electrodes spaced two inches apart and the DC. resistance measured with an ohmmeter. Specific resistance of the film in ohmcm. is calculated from the instrument reading in ohms as the product of the measured resistance times the width times the thickness all divided by the sample length, all in centimeter units.

Percent Carbon Black in Core Standard analytical methods can be employed for determining the concentration of carbon black in the filament or core material. A method suitable for use on ethylene plastics containing carbon black is described in or can be derived from the ASTM Method D1603-68. This is a thermogravimetric method suitable for use in the absence of any nonvolatile pigments or filler materials other than carbon black.

EXAMPLE 1 Concentric sheath/core filaments are prepared having a sheath of 45 RV 66-nylon and a polyethylene core containing 20 percent extra-conductive furnace black. The carbon black is an oil furnace black, extraconductive Vulcan XC-72, (Fixed Carbon 98 percent, Volatiles 2 percent, Particle Size 30 millimicrons, Electrical Resistivity lowest) available from the Cabot Corp., 125 High St.,' Boston, Mass. 02110. This black is described in their Technical Bulletins S-8 and 1518/173. The carbon black dispersion is prepared by mixing the carbon black at about 120C. with a low density (0.9T6) poly ethylene resinfrnel t index 23; (Alat hon 2821 by Du Pont), by milling in a dough mixer. The black is added slowly and the mixture cast 10 minutes after completion of addition. This polyethylene resin is selected for its softness. (Other useful resin compositions are a low density (0.919) polyethylene, melt index 1.9 [Alathon 20 by Du Pont] alone and blended 'with to 40 percent of an oil or wax). The molten carbon black mixture is filtered through a 100 X 100 mesh screen and extruded. Pressed films show excellent dispersion and conductivity with a specific resistance of 12.7 ohm-cm. Using this as the core, sheath/core continuous filaments, (three 65 denier monofilaments), are spun at 425 ypm wherein the total I denier is held constant and the core volume decreased by changing pump speeds to produce the items of Table l. The core volume is established from the pumping rate and confirmed by cross-section analysis of the fila ments at 200 X magnification. A 3-hole stainless steel spinneret is used wherein the sheath and core polymers are fed concentrically and individually until emerging at the face of the spinneret. An insert capillary is used to carry the core polymer composition to the spinneret face where it exits surrounded by the sheath polymer The filaments are spun at about 65 'dpf. They are then drawn 3.06X at about 200 ypm ona curved heated plate maintained at 150C. Yarn physical and electrical properties are shown in Table 1.

TABLE 1 Item 1 2 3 4 5 Core Volume 50 40 25 18 12 Yarn (Filament) Denier 21.4 20.6 21.4 21.2 19,9 Tenacity, gpd 1.5 1.9 2.4 2.8 3.4 Elongation, 26.2 36.4 30.3 54.7 57.4 lnitial Modulus, gpd 15.3 17.9 25.1 20.3 25.2 Core Resistance X 10, ohms/inch/ filament 2.5 6.7 4.0 13.3 Breakdown Voltage, KV 1.6 3.4 3.4 4.6 Carpet Static Propensity, KV (as in Ex-' ample 11 2.0 3.0 2.8 3.0 2.6

*As calculated from microamperes measured at 2 kilovolts The test'ca'rpets of Table l are made of a commercial 3700 denier/204 filament 66-ny1on bulked, trilobal, continuous filament carpet yarn in a -inch pile height. One yarn end of the conductive fiber (about 0.56 percent by weight) is plied upon coning with the carpet yarn, and tufted. The visibility of the conductive fila-.

ments decreases noticeably in the carpet with the reduction in core volume.

EXAMPLE 11 Preparation of Sheath Polymer A 317.5 kilogram aqueous solution containing 50 percent by weight of hexamethylene diammonium adipate (66-nylon salt) is charged into a stainless steel vessel to which is added 721 grams of a solution containing 10 percent by weight manganous hypophosphite [Mn( H PO in water; 70 grams of a solution containing 25 percent by weight acetic acid, and 100 m1. of a silicone antifoam 11.2 percent concentration. The charge is concentrated by evaporation to about percent solids by weight and transferred to a stainless steel autoclave equipped with an agitator. The autoclave is purged of air with inert gas and is heated to about 200C. to a pressure of 17 atmospheres. A 14.83 kilogram titanium dioxide (Ti-pure Rutile, Titanium Dioxide R-960, E. I. du Pont' de Nemours & Co., Wilmington, Delaware) slurry prepared as 49 percent by weight in water is charged with agitation into the pressurized autoclave. The heating is continued until the temperature reaches 273C. and the pressure is gradually re- I duced to the atmospheric pressure. The polymerization cycle is continued as in Example I of US. Pat. No. 2,163,636. Upon completion of the polymerization reaction, the molten polymer is extruded in the form of about A inch strands. After quenching with water they are cut into A X 3/ 16 inch chips suitable for remelting in a spinning assembly. The flake has these properties:

Relative viscosity 43.5 (NH 46.0 eq./l0 g.

TiO 5.04%

Mn(H PO 0.048%

Core Polymer Composition (by weight) Polyethylene: 70%

Conductive Carbon of Example I: 30%

Polyethylene. Alathon PE-4318 Low density polyethylene (density 0.916, Melt lndex 23 ASTM-D- 1238) manufactured by E. l. du Pont de Nemours.& Co., for injection molding. It contains 50 ppm antioxidant to improve thermal and aging stability.

Preparation In a 1 gallon capacity double arm dough mixer are charged 1905 grams of polyethylene and 816.5 grams of the carbon black. The composition is mixed for 30 minutes at 140C., extruded, filtered through a 100 X 100 mesh screen and pelletized.

The product shows the following properties:

Specific Resistance: (of a film cast at about 180C.)

2.9 to 4.2 ohm-cm.

% Carbon Black Analysis: 30.2%

% Moisture: 0.04%

If the moisture content is greater than 0.1 percent the pellets should be dried at 70C. and under vacuum for 24 hours before spinning.

Spinning The sheath and core polymers are cospun on a screw melter spinning machine using a spinneret assembly to spin concentric sheath/core filaments bythe technique shown in US Pat. No. 2,936,482.

The sheath polymer is-fed at 19.8 gm./min. (as calculated from pump capacity and speed) and core polymer at 0.7 gm./min. (as calculated from pump capacity and speed) throughputs to provide a concentric sheath- /core composition of 96 percent sheath and 4 percent core by volume. During spinning the sheath and core polymer temperatures in the screw melter are set at:

Sheath Polymer Core Polymer The spinning block temperature is 293C. Both sheath and core polymer supply hoppers are purged with inert gas.

The relative viscosity of sheath polymer as coming from the spinneret (free fall) is about 56, the increased RV resulting from further polymerization of dried 66- nylon in the screw melter. The spinning speed is approximately 890 ypm. The collected spun yarn is gray in color and has these properties:

Finish on yarn: 1.0%

Percent Core, by Volume: 4%

Percent Sheath, by Volume: 96%

Bundle Spun Denier: 60

No. of Filaments/Bundle: 3

Reflectance: 37-40% Drawing The'conductive 60-3 denier spun yarn is drawn on a draw-twisting machine at 2.7X draw ratio, 400 ypm winding speed, and 180C. shoe temperature.

The drawn yarn properties are:

No. of Filaments: 3

Tenacity, gpd: 3.8

Elongation: 35%

Modulus: l3 (gpd at elongation) Core Resistance (Bundle): 4.7 X 10" ohm/inch Reflectance: 34%

Cobulking One end of an approximately 3400 denier, 160 filament nylon 4-void hollow filament yarn of the type shown in Br. Pat. No. 1,292,388 is cobulked with one end of the conductive yarn on one position of the hollow filament spinning machine. The yarns are combined in a hot chest under 10-20 g. tension at the last chest roll wrap before entering the bulking jet. The chest roll is at 195C. and yarn velocity is 1185 ypm. The cobulking is done by passing the yarn through an air jet operated at psig and 240C. as described in Belgium Patent No. 573,230 to produce filaments having random, three-dimensional curvilinear crimp with alternating regions of S and Z filament twist. The yarn is then cooled and passed to windup.

The tensile properties of the cobulked yarn are essentially the same as the unmodified product. Mockdyed level loop carpets k inch pile height, 29.4 ounces/- square yard, 5/32 inch gauge, 7 stiches per inch) made from yarns containing the conductive filaments (test) and from yarns containing no conductive filaments (control) with a commercial nonwoven polypropylene backing (Typar by Du Font) and latexed with a commercial latex give the following static propensities at 20 percent RH and 70F.

Test Control The static test is AATCC Test Method 134-1969 with changes as adopted by the Carpet and Rug lnstitute, September, 1971.

ln greige or mockdyed carpets the 20-3 denier conductive filaments give a very slight blueish cast. Dyed bulked continuous filament carpets containing conductive filaments show no difference in most of the solid color shades and only slight differences in certain solid light colors, e.g., yellow, orange and pink, when compared with the control carpet.

If desired, the filaments of the invention may be used in staple form, e.g., at from 0.5 to 5 percent by weight with nonconductive staple in carpet yarn.

EXAMPLE III This example demonstrates that care must be exercised in drawing filaments of this invention to avoid loss of conductivity.

Filaments are spun of an eccentric sheath/core configuration with a 66-nylon sheath of 44 relative viscosity and containing 0.3 percent TiO and a 6-nylon core (45 relative viscosity 31.8 equiv. NH end groups/ 10 grams) having nominally 20 percent carbon black of the type in Example 1. The filaments are 40 percent core by volume. The 3-filament yarn has a spun denier of about 79. The yarn is cold drawn using a draw-pin. As shown in Table 2, the yarn resistance upon cold drawing is found to increase as a function of the draw ratio. When the yarn is hot drawn without a pin using a curved heated plate at about C., essentially no increase in resistance is encountered. It is speculated that heating of the yarn in a heated draw zone upon drawing permits softening of the core enough to prevent core breakage or disruption of the carbon particle distribution required for conductivity.

TABLE 2 Draw Ratio Core Resistance (ohgns/inch/ '3-filaments 1 (undrawn) 1.5 l 1.5 6.l l0 3.0 5X10 3.0 (hot drawn) 0.7 l0"" *As calculated from the three filaments measured individually.

EXAMPLE IV Sheath Polymer Poly(ethylene terephthalate) flake having a relative viscosity of 23 i 2 measured on 0.8 gm. polymer in ml. of hexafluoroisopropanol at C.

Core Polymer 6-Nylon 22 percent conductive carbon black of Example '1.

Preparation A p're-dispersed slurry of 22.680 kilograms conductive carbon (Cabot XC-72), 86.180 kilograms of cap- I to 7 hours, the pressure is reduced gradually within 1V2 hours from 250 psig to atmospheric pressure (reducing cycle). The polymer is then extruded at 278C. into a continuous ribbon which is quenched with water and cut into Vs inch flake. The flake is washed with water for about 4 hours in a stirred kettle heated at 95C., to

remove monomer. This operation is repeated three times and at the end about 6.3 percent caprolactam is extracted. The polymer is then dried under vacuum (25 inches Hg) until the moisture content is less than 0.3 percent. The flake is remelted, extruded and filtered through a screen filter of increasing mesh (30 to 200) and pelletized, then vacuum dried to less than 0.03 percent moisture content.

The specific resistance of films cast from this polymer varies between 10-60 ohm-cm.

Spinning and Drawing The sheath and core polymers are co-spun and drawn on a coupled spin-draw machine at 1500 ypm windup speed (as calculated from the speed of the windup roll in rpm).

Using a screw melterthe sheath polymer is fed to a spinneret at 29.7 gm./min. (as calculated from denier spun and windup speed) and core polymer at 6.7 gm./min. (as calculated from denier spun and windup speed) throughputs to provide a concentric sheath- /core composition at 81 percentsheath (as calculated from throughputs) and 19 percent core (as. calculated from throughputs) by weight. During spinning the screw melters temperatures are set at:

Sheath Polymer Core Polymer Screw Melter Zone Temperature C. Temperature C. Top 249 206 Middle 281 250 Bottom 289 265 The drawn yarn is black in color and has these properties:

No. of Filaments/Bundle 1 Denier 19.02

Total Finish on Yarn 1.83

Core Resistance 3.3 X 10 ohm/in.

Tenacity, gpd 2.5

Elongation, 39.9 v

Modulus, gpd at 10% Elongation 13.6

EXAMPLE V Sheath Polymer Poly(ethylene terephthalate) flake having an RV of Core Polymer Prepared as in Example II.

Spinning The sheath and core polymers are co-spun as in Example II at 860 ypm. The sheath polymer is fed at 36.3 grams/minute (as calculated from pump speed and capacity) and core polymer 1.38 grams/minute (as calculated from pump speed and capacity). throughputs to provide a concentric sheath/core composition of 96 percent sheath and 4 percent core by volume as determined by measurement of the cross-section under magnification.

During spinning the screw melter temperature for the sheath polymer is set at:

Core Polymer Screw Melter Temperature C.

Zone 1 286 114 (Top) Zone 2 284 184 (Middle) 242 (Bottom) and the spinning block temperature at 292C.

The yarn is spun at 60 denier/ 3 filaments (60-3). Drawing 60-3 Denier sheath/core yarn is drawn at 454 ypm and 3.8X draw ratio and 97C. hot shoe temperature.

The drawn yarn properties are:

Denier 17.2

No. of Filaments 3 Core Resistance, ohm/in./fil. 6.76 X 10 Tenacity, gpd 5.3

Elongation, 21.5

Modulus, M, 43.2 gpd at 10% elongation The sheath/ core test yarn is cotextured with a commercial l50-34-polyester yarn on a Leesoria 570 falsetwist texturing machine. The cotextured yarn (1 end 17.2-3 sheath-core with 1 end -34 polyester) is woven into a Suisse Pique double knit fabric. This fabric is dyedand finished using conventional methods. After 30 washes the fabric is tested on asta tic tester (Presco Scientific Co., electrometer model E525) and compared with the control fabric made from the same polyester yarn alone and processed under identical conditions.

Electrostatic Charge on Fabric (volts) After 0 second After I20 seconds Test Fabric 380 Control Fabric 2750 25 50 Good electrostatic protection for the test item is indicated.

mer as in Example II, and a 6-nylon core polymer con-' taining 28% carbon black prepared as in Example IV. Filaments 96 percent by volume sheath and 4 percent core are drawn 3.0X over a 180C. curved (24 inch) hot plate. The yarn properties are:

Bundle denier 20.2

Tenacity, gpd 3.18

Elongation, 49.1

Modulus, Mi, gpd 24.4

Core Resistance 4.5 X 10 ohm/in.fil.

Reflectance, 32 l Cobulking The conductive yarn is cobulked as in Example II with basic dyeable 1225-68 66-nylon hollow (4 voids) continuous filament carpet yarn (Type 854 Antron II by Du Font) and tufted at A inch pile height, 14 ounces/square yard level loop carpets as outlined in Example II. I

Mockdyed carpet reflectance and static propensity are compared against a control carpet made without conductive yarn.

Carpet Static Carpet Propensity* Reflectance Test 1.5 to 2.4 K Volts 65 Control 8.6 to 9.8 75

* As in Example II Visual rankings of the carpets are in agreement with the measured carpet reflectance.

EXAMPLE VII Filaments (4 ends of 60 spun denier, 3 filaments) having a nylon sheath and a polyethylene core essentially the same as those in Example [I are prepared, for use in staple, having properties as follows:

Finish on Yarn, 0.43

Percent Core, by weight: 3.5%

Percent Sheath, by weight: 96.5%

Percent Carbon in Core: 32.3%

Reflectance: 39%

Bundle (12 fil.) Core Resistance: X ohm/inch The spun yarn is drawn by combining eight ends, on an experimental draw machine at 3.0X draw ratio, 230 ypm. winding speed and 180C. hot shoe temperature.

The drawn yarn properties are:

Bundle denier: 690

No. of Filaments: 96

Tenacity, gpd.: 4.72

Elongation, 18.5

This conductive yarn bundle is cut to approximately 6.5 inch length pieces and blended with commercial Du Pont T-838, 66-nylon carpet staple during carding at 0.6, 2 and 5 percent quantities. The blends are processed under normal staple conditions to make spun yarns of 2.4 cotton count/2 ply, 3.5Z/3.5S twist. The

yarns are heat set in an autoclave and then tufted into 35 oz./square yard, 5/32 inch gauge, A inch pile height saxony style cut pile carpets with a Typar polypropylene backing and latexed with a commercial latex. The carpets are scoured and dyed conventionally with a mixture of 3 commercial yellow, red and blue acid dyes.

The dyed carpets give the following static propensi ties on shuffle test at 20 percent RH and -.70F.

Ratio of Antistat Fiber Carpet Static Propensity,

to Base Fiber Kilovolts 0/100 9.4 0.6/99.4 3.2 2.0/98.0 2.5 5.0/95.0 1.9 as in Example II EXAMPLE VIII having a trilobal cross-section with a modification ratio Items C through I-I have round filament crosssections.

Item C comprises filaments having a 66-nylon sheath containing 5 percent titanium dioxide and a core containing 30 percent carbon black in a polyolefin base comprised of 40 percent polypropylene, 20 percent polyethylene and 10 percent Nordel 1500, a commercial elastomer based on a terpolymer of ethylene, propylene and a non-conjugated diene from E. I. du Pont Nemours and Company.

Item D comprises filaments having a sheath of a commercial polypropylene resin (Shell PWD-15 2) and core composition as in Item A.

Item Eemploys the same sheath as in Item D with a core material consisting of a polycaprolactone commercial resin (Union Carbide PCL-700) containing 30 percent carbon black.

Item F employs a sheath of 66-nylon containing 5 percent titanium dioxide pigment and a core of a commercial polypropylene resin (Hercules 8MSR) containing 25 percent carbon black.

Item G employs a polypropylene sheath as in Item D and a core of a commercial polyethylene ether resin (Du Pont TLF 16815) containing 26 percent carbon black.

Item H is a non-antistatic control item having a nylon sheath as in Item A and the same polyethylene resin core containing no carbon black.

Filament properties for these items are shown in Table 3.

TABLE 3 Percent core (by Yarn Core yarn/ Draw Tenacity, Elong., volume refiec., resist.. Item ratio Denier g./d. percent Mod. mi. X-section) percent ohm/inch/fil.

21.6 2.65 68.4 21.6 10 28.5 3 21.1 3.00 81.8 22.1 35 2.46 110.!) 2.1!] ($2.8 l4.2 3 49 ll 42. 3.6) 120 28.3 7.5 11 ll 104.4 1.72 I50 [4.7 7.4 12.6 0.3 33.3 2.4!! 34.2 17. 7.5 31.3 80 56. 7 3. 2!! lllhl 28. 7 ll 0. 3 19. l 3. 87 34. 5 23. 6 4 10 What is claimed is:

l. A novel synthetic filament having antistatic properties comprising a continuous, nonconductive sheath of a synthetic thermoplastic fiber-forming polymer surrounding an electrically conductive polymeric core comprised of electrically conductive carbon black dispersed in a thermoplastic synthetic polymer, said sheath comprising at least 50 percent of the filament cross-sectional area and said filament core having an electrical resistance of less than 10 ohms per inch at a direct current potential of two kilovolts.

2. The filament of claim 1 wherein the sheath constitutes at least 80 percent of the filament cross-sectional area and the conductive core contains more than percent by weight of carbon black.

3. The filament of claim 1 having a tenacity of at least 1.5 grams per denier.

4. The filament of claim 1 wherein the sheath constitutes at least 90 percent of the filament cross-sectional area.

5. The filament of claim 4 wherein the sheath is at least 3 microns in thickness.

6. The filament of claim 4 wherein the sheath is delustered such that the filament has a light reflectance value of greater than 20 percent.

- 7. The filament of claim 4 wherein the sheath contains from 2 to 7 percent by weight of titanium dioxide as a delusterant.

8. The filament of claim 1 wherein the sheath is 6-6 nylon and the synthetic polymer of the core is 6-nylon.

9. The filament of claim 1 wherein the sheath is a polyamide and the synthetic polymer of the core is polyethylene. v g

10. The filament of claim 1 wherein the sheath is a polyester and the synthetic polymer of the core is polyethylene.

11. The filament of claim 1 wherein the core is lower melting than the sheath.

12. The filament of claim 1 having a denier of less than 50.

13. The filament of claim 1 wherein the filament core has an electrical resistance of less than 10 ohms per inch at a direct current potential of two kilovolts.

14. A continuous filament yarn comprising a mixture of nonconducting synthetic filaments and less than 20 percent by weight of filaments of claim 1.

15. A continuous filament yarn comprising a cobulked mixture of nonconducting synthetic filaments and less than 20 percent by weight of filaments of claim 1.

. 16. A mixture of nonconducting polyamide filaments and less than 20 percent by weight of filaments of claim 1 having a polyamide sheath.

17. A mixture of staple fibers comprising nonconducting synthetic filaments and less than 20 percent by weight of filaments of claim 1. v

18. A carpet wherein the face yarn contains a filament of claim 1.

19. A novel synthetic filament having antistatic properties comprising a continuous nonconductive polyamide sheath surrounding an electrically conductive core electrical resistance of less than 10 ohms/inch at a direct current potential of two kilovolts.

20. A continuous filament yarn comprising a co- I bulked mixture of nonconducting synthetic filaments and less than 20 percent by weight of filaments of claim

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3969559 *27 May 197513 Jul 1976Monsanto CompanyMan-made textile antistatic strand
US4107129 *24 Feb 197715 Aug 1978Toray Industries, Inc.Acrylonitrile polymer, polymer cn on black
US4115620 *19 Jan 197719 Sep 1978Hercules IncorporatedConjugate filaments
US4129677 *31 May 197712 Dec 1978Monsanto CompanyMelt spun side-by-side biconstituent conductive fiber
US4145473 *25 Feb 197520 Mar 1979E. I. Du Pont De Nemours And CompanyAntistatic filament having a polymeric sheath and a conductive polymeric core
US4205359 *21 Sep 197827 May 1980Onoda Cement Co., Ltd.Safety type electric field curtain apparatus
US4207376 *14 Jun 197910 Jun 1980Toray Industries, Inc.Antistatic filaments having an internal layer comprising carbon particles and process for preparation thereof
US4216264 *4 Aug 19785 Aug 1980Kanebo, Ltd.Conductive composite filaments
US4234655 *1 Aug 197918 Nov 1980Chisso CorporationCrystalline polypropylene, ethylene-vinyl acetate copolymer optionally saponified
US4258097 *26 Apr 197924 Mar 1981Brunswick CorporationFor use as carpeting
US4289627 *30 Aug 197915 Sep 1981Hoechst AktiengesellschaftFabric of synthetic fibers wherein individual fibers are bound to each other as to be unshiftable
US4303733 *21 Jan 19801 Dec 1981Akzona IncorporatedFilament with conductive layers
US4309479 *7 Apr 19805 Jan 1982Kanebo, Ltd.Conductive composite filaments
US4323626 *18 Sep 19806 Apr 1982Chisso CorporationCrystalline polypropylene, ethylene-vinyl acetate-vinyl alcohol te
US4420534 *28 May 198113 Dec 1983Kanebo Synthetic Fibers Ltd.Thermoplastic polymer with metal oxide particles
US4432924 *9 Apr 198221 Feb 1984Lion CorporationControlling the heating during orientation; high strength
US4473617 *15 Jan 198225 Sep 1984Akzo NvCarbon black, iron oxide or titanium dioxide pigment
US4756969 *19 Jun 198712 Jul 1988Toray Industries, Inc.Highly electrically conductive filament and a process for preparation thereof
US4900495 *8 Apr 198813 Feb 1990E. I. Du Pont De Nemours & Co.Sheath-core filaments of nonconductive polymer containing a minor amount of polystyrene surrounding a conductive polymer
US4997712 *5 Oct 19895 Mar 1991E. I. Du Pont De Nemours And CompanyHigh elongation to break
US5001813 *5 Jun 198926 Mar 1991E. I. Du Pont De Nemours And CompanyStaple fibers and process for making them
US5026603 *8 Nov 199025 Jun 1991E. I. Du Pont De Nemours And CompanyStaple fibers and process for making them
US5116681 *13 Aug 199026 May 1992E. I. Du Pont De Nemours And CompanyMultifilament; nonconductive component and electronconductive carbon dispersed in polymer matrix; carpets
US5126201 *28 Dec 198930 Jun 1992Kao CorporationAbsorbent article
US5147704 *6 Feb 199215 Sep 1992E. I. Du Pont De Nemours And CompanyCarpets made with anti-static yarns containing polystyrene
US5202185 *3 May 199113 Apr 1993E. I. Du Pont De Nemours And CompanySheath-core spinning of multilobal conductive core filaments
US5213865 *26 Aug 199125 May 1993Daiwa Co., Ltd.Antistatic mat
US5213892 *13 Jul 199025 May 1993Hoechst AktiengesellschaftAntistatic core-sheath filament
US5260013 *25 Nov 19929 Nov 1993E. I. Du Pont De Nemours And CompanySheath-core spinning of multilobal conductive core filaments
US5318845 *13 Jan 19937 Jun 1994Kuraray Co., Ltd.Core of nonconductive polyethylene terephthalate multifilament yarn surrounded by sheath of yarn of conductive polyamide core with conductive metal oxide and polyester sheath
US5549957 *24 Jun 199327 Aug 1996Negola; Edward J.Sheath-core
US5632944 *20 Nov 199527 May 1997Basf CorporationForming dispersion of chemical compound or particle additives in nonaqueous liquid carrier, blending in first, then second thermoplastic polymers, extruding through spinnerert, solidifying
US5641570 *20 Nov 199524 Jun 1997Basf CorporationMulticomponent yarn via liquid injection
US5645782 *30 Jun 19958 Jul 1997E. I. Du Pont De Nemours And CompanyProcess for making poly(trimethylene terephthalate) bulked continuous filaments
US5660804 *28 Feb 199626 Aug 1997Toray Industries, Inc.Highly oriented undrawn polyester fibers and process for producing the same
US5662980 *12 Dec 19962 Sep 1997E.I. Du Pont De Nemours And CompanyCarpets made from poly(trimethylene terephthalate) bulked continuous filaments
US5698148 *26 Jul 199616 Dec 1997Basf CorporationSheath-core spinning, quenching, drawing, relaxing and winding
US5776608 *6 Jun 19977 Jul 1998Basf CorporationProcess for making electrically conductive fibers
US5780156 *3 Oct 199614 Jul 1998Basf CorporationBiocomponet fibers having distinct crystaline and amorphous polymer domains and method making same
US5820805 *15 Jul 199713 Oct 1998Basf CorporationProcess for making multicomponent antistatic fibers
US5840425 *6 Dec 199624 Nov 1998Basf CorpMulticomponent suffused antistatic fibers and processes for making them
US5849232 *11 Apr 199715 Dec 1998Toray Industries, Inc.Process for producing highly oriented undrawn polyester fibers
US5851668 *19 Nov 199622 Dec 1998Hoechst Celanese CorpCut-resistant fiber containing a hard filler
US5876849 *2 Jul 19972 Mar 1999Itex, Inc.Cotton/nylon fiber blends suitable for durable light shade fabrics containing carbon doped antistatic fibers
US5885705 *29 Dec 199723 Mar 1999Basf CorporationPolycaprolactam core and polyamide sheath
US5888651 *25 Aug 199730 Mar 1999Basf CorporationColored bicomponent fibers
US5916506 *30 Sep 199629 Jun 1999Hoechst Celanese CorpElectrically conductive heterofil
US5952099 *20 Jan 199814 Sep 1999Basf CorporationProcess for making electrically conductive fibers
US5976998 *13 Oct 19982 Nov 1999Hoechst Celanese CorporationCut resistant non-woven fabrics
US6004674 *18 Dec 199821 Dec 1999Basf CorporationBicomponent fibers having contaminant-containing core domain and methods of making the same
US6039903 *18 Dec 199821 Mar 2000Basf CorporationProcess of making a bicomponent fiber
US6047775 *21 Jul 199911 Apr 2000Bucyrus International, Inc.Blast hole drill pipe gripping mechanism
US6057032 *10 Oct 19972 May 2000Green; James R.Yarns suitable for durable light shade cotton/nylon clothing fabrics containing carbon doped antistatic fibers
US6103372 *15 Dec 199815 Aug 2000Hoechst Celanese CorporationPoly(ethylene terephthalate) or a liquid crystalline polyester comprising monomer units derived from 6-hydroxy-2-naphthoic acid and 4-hydroxybenzoic acid; preferred fillers include tungsten and alumina; protective gloves
US6126879 *6 Aug 19983 Oct 2000Honeywell International Inc.Melt, wet or dry spinning blend of fiber-forming polymer and hard filler; protective gloves
US6127028 *13 Oct 19983 Oct 2000Hoechst Celanese CorporationComposite yarn comprising filled cut-resistant fiber
US6136436 *14 Aug 199724 Oct 2000Nyltec Inc.Soft silky large denier bicomponent synthetic filament
US6159598 *23 Nov 199912 Dec 2000The Pilot Ink Co., Ltd.Useful as doll hair the hair style of which is thermally shape-transformable to any desired shapes and is easily fixable to the transformed shape by cooling; artificial hair; wigs
US6159599 *13 Oct 199812 Dec 2000Honeywell International, Inc.Cut-resistant sheath/core fiber
US6159895 *29 Jun 199912 Dec 2000E. I. Du Pont De Nemours And CompanyAramid polymer catalyst supports
US6162538 *11 Feb 199919 Dec 2000Clemson University Research FoundationAromatic polyamides with fillers
US621079815 Dec 19983 Apr 2001Honeywell International, Inc.Cut-resistant gloves
US624209110 Apr 19965 Jun 2001E. I. Du Pont De Nemours And CompanyYarns comprised of bulked continuous filaments of poly(trimethylene terephthalate)
US628768928 Dec 199911 Sep 2001Solutia Inc.Nylon blend
US65281398 Sep 19984 Mar 2003Basf CorporationProcess for producing yarn having reduced heatset shrinkage
US663008716 Nov 20017 Oct 2003Solutia Inc.Process of making low surface energy fibers
US663708526 Oct 200128 Oct 2003E. I. Du Pont De Nemours And CompanyProcess for recycling articles containing high-performance fiber
US666623526 Oct 200123 Dec 2003E. I. Du Pont De Nemours And CompanyLightweight denim fabric containing high strength fibers and clothing formed therefrom
US6675838 *25 Oct 200113 Jan 2004Ipg Technologies, Inc.For use in a combustible environment; clean room garments
US684644820 Dec 200125 Jan 2005Kimberly-Clark Worldwide, Inc.Method and apparatus for making on-line stabilized absorbent materials
US688146810 Jan 200319 Apr 2005Honeywell International Inc.Process for producing yarn having reduced heatset shrinkage
US701362816 Dec 200321 Mar 2006E. I. Du Pont De Nemours And CompanyProcess for making poly(trimethyleneterephthalate) bulked continuous filaments, the filaments thereof and carpets made therefrom
US711531123 Oct 20033 Oct 2006Central Products CompanyAnti-static woven flexible bulk container
US715688326 Jul 20042 Jan 2007E. I. Du Pont De Nemours And CompanyLightweight protective apparel
US733869721 Mar 20034 Mar 2008High Voltage Graphics, Inc.Co-molded direct flock and flock transfer and methods of making same
US734476924 Jul 200018 Mar 2008High Voltage Graphics, Inc.Flocked transfer and article of manufacture including the flocked transfer
US73513683 Jul 20031 Apr 2008High Voltage Graphics, Inc.Flocked articles and methods of making same
US736478213 Dec 200029 Apr 2008High Voltage Graphics, Inc.Flocked transfer and article of manufacture including the application of the transfer by thermoplastic polymer film
US73812844 Jun 20033 Jun 2008High Voltage Graphics, Inc.Flocked transfer and article of manufacture including the application of the transfer by thermoplastic polymer film
US739055223 Sep 200324 Jun 2008High Voltage Graphics, Inc.Flocked transfer and article of manufacturing including the flocked transfer
US7393576 *14 Jan 20051 Jul 2008High Voltage Graphics, Inc.Carrier coated with release adhesive bonded to parallel conductively coated, concentric multi-component fibers with a polyester outer surface; other fiber ends are bonded to permanent adhesive; heat resistance; loft retention
US74022224 Jun 200322 Jul 2008High Voltage Graphics, Inc.Flocked transfer and article of manufacture including the flocked transfer
US74106823 Jul 200312 Aug 2008High Voltage Graphics, Inc.Flocked stretchable design or transfer
US74135813 Jul 200319 Aug 2008High Voltage Graphics, Inc.Process for printing and molding a flocked article
US746548530 Nov 200416 Dec 2008High Voltage Graphics, Inc.Process for dimensionalizing flocked articles or wear, wash and abrasion resistant flocked articles
US7472535 *4 May 20046 Jan 2009Casual Living Worldwide, Inc.Coreless synthetic yarns and woven articles therefrom
US7472536 *29 Jun 20046 Jan 2009Casual Living Worldwide, Inc.Coreless synthetic yarns and woven articles therefrom
US753783022 Aug 200726 May 2009E.I. Du Pont De Nemours And CompanyPolymer or copolymer derived from a monomer selected from 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, and mixtures thereof; low thermal shrinkage; antistatic staple fiber and flame resistant fibers having a limiting oxygen index of 21 or greater; protective clothing
US753783122 Aug 200726 May 2009E.I. Du Pont De Nemours And CompanyFlame resistant spun staple yarns made from blends of fibers derived from diamino diphenyl sulfone and modacrylic fibers and fabrics and garments made therefrom and methods for making same
US761870722 Aug 200717 Nov 2009E.I. Du Pont De Nemours And CompanyFlame resistant spun staple yarns made from blends of fibers derived from diamino diphenyl sulfone and modacrylic fibers and fabrics and garments made therefrom and methods for making same
US763237122 Oct 200715 Dec 2009High Voltage Graphics, Inc.Flocked transfer and article of manufacture including the application of the transfer by thermoplastic polymer film
US770019022 Aug 200720 Apr 2010E.I. Du Pont De Nemours And CompanyProtective clothing made from fabric comprising a fireproofing staple polyamide yarn based on of bis/m- or p-aminophenyl sulfone and terephthalicacid and and a textile staple of poly-m-phenylene isophthalamide having a limiting oxygen index of 21 or greater; tensile strength; durability;
US770019122 Aug 200720 Apr 2010E.I. Du Pont De Nemours And CompanyProtective clothing made from fabric comprising a fireproofing staple polyamide yarn based on of bis/m- or p-aminophenyl sulfone and terephthalicacid and and a textile staple of poly-m-phenylene isophthalamide having a limiting oxygen index of 21 or greater; tensile strength; durability;
US773203927 Nov 20028 Jun 2010Kimberly-Clark Worldwide, Inc.Absorbent article with stabilized absorbent structure having non-uniform lateral compression stiffness
US774499911 Jul 200829 Jun 2010E. I. Du Pont De Nemours And CompanyCrystallized meta-aramid blends for improved flash fire and arc protection
US774958920 Sep 20066 Jul 2010High Voltage Graphics, Inc.Flocked elastomeric articles
US77496013 Apr 20096 Jul 2010E. I. Du Pont De Nemours And CompanyPolymer or copolymer derived from a monomer selected from 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, and mixtures ; low thermal shrinkage; antistatic staple fiber and flame resistant fibers having a limiting oxygen index of 21 or greater; protective clothing
US779916427 Jul 200621 Sep 2010High Voltage Graphics, Inc.Flocked articles having noncompatible insert and porous film
US781993622 Aug 200726 Oct 2010E.I. Du Pont De Nemours And CompanyFilter felts and bag filters comprising blends of fibers derived from diamino diphenyl sulfone and heat resistant fibers
US782397930 Jan 20092 Nov 2010Casual Living Worldwide, Inc.Woven articles from synthetic yarn
US800788928 Apr 200630 Aug 2011High Voltage Graphics, Inc.Flocked multi-colored adhesive article with bright lustered flock and methods for making the same
US8017233 *18 May 200413 Sep 2011Toray Industries, Inc.Fibers having excellent responsiveness to magnetic fields and excellent conductivity, as well as articles made of the same
US80696422 Jun 20096 Dec 2011E.I. Du Pont De Nemours And CompanyCrystallized meta-aramid blends for improved flash fire and superior arc protection
US80696432 Jun 20096 Dec 2011E. I. Du Pont De Nemours And CompanyLimited-antimony-content and antimony-free modacrylic / aramid blends for improved flash fire and arc protection
US81335848 Apr 201013 Mar 2012E.I. Du Pont De Nemours And CompanyCrystallized meta-aramid blends for flash fire and arc protection having improved comfort
US816674322 Aug 20071 May 2012E.I. Du Pont De Nemours And CompanySpun staple yarns made from blends of rigid-rod fibers and fibers derived from diamino diphenyl sulfone and fabrics and garments made therefrom and methods for making same
US816826214 Jun 20101 May 2012High Voltage Graphics, Inc.Flocked elastomeric articles
US835405014 Jan 200815 Jan 2013High Voltage Graphics, Inc.Co-molded direct flock and flock transfer and methods of making same
US847590514 Feb 20082 Jul 2013High Voltage Graphics, IncSublimation dye printed textile
US20120100386 *17 Oct 201126 Apr 2012Toyota Boshoku Kabushiki KaishaHeating yarn and woven or knitted fabric using this heating yarn
US20120237766 *16 Mar 201120 Sep 2012Kb Seiren, Ltd.Conductive conjugate fiber
DE2611830A1 *19 Mar 197630 Sep 1976Du PontGemisch und mischgarn aus gekraeuselten polyamidstapelfasern und verfahren zur herstellung derselben
DE2707275A1 *19 Feb 197725 Aug 1977Toray IndustriesAcrylfasern oder -faeden mit verminderter statischer elektrizitaet
DE2718343A1 *25 Apr 197717 Nov 1977Dow Badische CoIntegrales, elektrisch leitfaehiges textilfilament
EP0056667A1 *11 Jan 198228 Jul 1982Akzo N.V.Synthetic technical multifilament yarn and process for the manufacture thereof
EP0072550A1 *13 Aug 198223 Feb 1983Toray Industries, Inc.A neutron-shielding composite fiber and a method of manufacturing same
EP0356100A2 *14 Aug 198928 Feb 1990Herschel SternliebWhite blackout fabric
EP0399397A2 *18 May 199028 Nov 1990E.I. Du Pont De Nemours And CompanySheath-core spinning of multilobal conductive core filaments
EP0899364A2 *10 Aug 19983 Mar 1999Basf CorporationColored bicomponent fibers
EP1754812A24 Aug 200421 Feb 2007E.I.Du Pont de Nemours and CompanyFabric for use in protective apparel
WO2007105494A1 *1 Mar 200720 Sep 2007Masao KawamotoConductive composite fiber and method for producing same
WO2010136729A127 May 20102 Dec 2010Arkema FranceMultilayer conductive fiber and method for producing the same by coextrusion
WO2010141549A12 Jun 20109 Dec 2010E. I. Du Pont De Nemours And CompanyCrystallized meta-aramid blends for improved flash fire and superior arc protection
WO2010141554A12 Jun 20109 Dec 2010E.I. Du Pont De Nemours And CompanyLimited-antimony-content and antimony-free modacrylic / aramid blends for improved flash fire and arc protection
WO2011126999A15 Apr 201113 Oct 2011E. I. Du Pont De Nemours And CompanyCrystallized meta-aramid blends for flash fire and arc protection having improved comfort
WO2012057992A210 Oct 20113 May 2012E. I. Du Pont De Nemours And CompanyArc resistant garment containing a multilayer fabric laminate and processes for making same
WO2013032562A118 Jun 20127 Mar 2013E. I. Du Pont De Nemours And CompanyHigh moisture regain yarn, fabrics, and garments having superior arc protection
WO2013032563A118 Jun 20127 Mar 2013E. I. Du Pont De Nemours And CompanyArticle of thermal protective clothing
WO2014018697A125 Jul 201330 Jan 2014E. I. Du Pont De Nemours And CompanyFiber blends, yarns, fabrics, and garments for arc and flame protection
Classifications
U.S. Classification361/220, 428/375, 264/172.15, 57/905, 57/244, 139/426.00R, 57/904, 57/245, 428/373, 57/205, 264/105
International ClassificationD02G3/44, D01F1/09, D02G3/04, D03D15/00, D04H5/00, D01F8/04
Cooperative ClassificationD02G3/441, Y10S57/905, D01F8/04, D01F1/09, Y10S57/904
European ClassificationD01F8/04, D02G3/44A, D01F1/09