US 3851456 A
Metallic fibers, made for example of stainless steel, are arranged substantially circumferentially of a yarn so as to enclose nonmetallic fibers, such as various synthetic or natural fibers. Each of the metallic fibers has a polygonal cross section, such that the relatively sharp-edged corners of these metallic fibers extend throughout the length of the yarn. The electrostatic charges that have built up on any part of the yarn are efficiently collected by the sharp-edged corners of the metallic fibers and are dissipated throughout their length.
Description (OCR text may contain errors)
nlted States Patent 11 1 1111 3,851,456 Hamada et al. Dec. 3, 1974 ANTISTATIC YARN CONSISTING OF A 3,288,175 ll/l966 Valko 57/157 AS MIXTURE 0F METALLIC AND 3,422,460 1/ 1969 Burke et al. 57/139 X 3,582,444 6/1971 Ngo et a1 57/140 BY NONMETALLIC FIBERS 3,600,884 8/1971 Yazawa et a1. 57/139  Inventors: Koichi Hamada; Tatsuya Kunieda, 3,601,970 8/1971 Roberts 57/145 5 both of Osaka, Japan Primary Examiner-Donald E. Watkins  Asslgnee' Eggs Selsen Osaka Attorney, Agent, or FirmIrving M. Weiner  Filed: July 24, 1973 57 ABSTRACT 1 1 pp 332,191 Metallic fibers, made for example of stainless steel, are arranged substantially circumferentially of a yarn  US. Cl. 57/140 BY so as to enclose nonmetamc fibers Such as various 51 Int. Cl 002 3/12 Synthetic or natural fibers Each of the metallic fibers  Field of Search n /55 T 5 140 BY has a polygonal cross section, such that the relatively R Sharp-edged Corners of these metallic fibers extend throughout the length of the yarn. The electrostatic charges that have built up on any part of the yarn are  References Cited efficiently collected by the sharp-edged corners of the metallic fibers and are dissipated throughout their UNITED STATES PATENTS length 1.334.257 3/1920 Partington 57/146 x 1,531,862 3/1925 Larned 57/139 ux I 4 Claims, 3 Drawmg Flgllres BACKGROUND OF THE INVENTION This invention relates generally to yarns or fibers, and more specifically to a novel and improved antistatic yarn composed of both metallic and nonmetallic fibers. I
It is well known that electrostatic charges are readily built up, as by friction, on carpets, garments and other textile products made of synthetic fibers. In order to prevent the buildup of such static electricity and the resultant sparking, there have been widely used the yarns consisting of a mixture of the synthetic fibers and metallic fibers such as those made of stainless steel. What is important for the manufacture of these kinds of yarns is that the metallic and the nonmetallic fibers be sufficiently united together to form a coherent whole usable as a yarn.
A certain degree of such cohesion has been accomplished in the prior art antistatic yarns in which nonmetallic fibers are combined with metallic fibers whose surface irregularities, produced almost inevitably at the instant of molding, are left unburnished. However, the antistatic effect of these prior art yarns has been unsatisfactory, because the metallic fibers have been mostly buried inwardly of the yarns or, in some instances, have been coiled around the strands of the nonmetallic fibers at an appropriate pitch. In this manner the buildup of static electricity is prevented only at those parts of the yarns where the nonmetallic fibersare in contact with the metallic fibers, but not in other parts where the nonmetallic fibers are incontact with each other.
SUMMARY OF THE INVENTION which consists essentially of a mixture of a plurality of metallic fibers and a plurality of nonmetallic fibers, wherein the metallic fibers each have a substantially polygonal cross section and are arranged substantially circumferentially of the yarn.
In view of the noted difficulties of the prior art it is an object of this invention to provide a novel and improved antistatic yarn in which metallic and nonmetallic fibers are united together in such a manner that the buildup of static electricity is prevented invariably throughout the length of the yarn.
Another object of the invention is to provide an antistatic yarn in which the metallic and the nonmetallic fibers are in a favorable state of cohesion.
With these objects in view and the other objects here: inafter made apparent, this invention provides an antistatic yarn in which a plurality of nonmetallic fibers are combined with a plurality of metallic fiberseach having a substantially polygonal cross section, in such a manner that the metallic fibers are arranged substantially circumferentially of the yarn. The nonmetallic and the metallic fibers may be combinedeither individually or in the form of strands or plies.
The features which are believed to be novel and characteristic of this invention are set forth with particularity in the claims appended hereto. The invention itself, however, together with the further objects and advantages thereof, will be best understood from the following description taken in conjunction with the accompanying drawings which illustrate, by way of example only, some preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1 is a perspective view of an antistatic yarn formed by way of a preferred embodiment of this invention,
FIG. 2 is an end or cross sectional view of another preferred embodiment of the invention; and
FIG. 3 is also an end or cross sectional view of still another preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION It is imperative according to the invention that'the cross section of each of the metallic fibers be substantially polygonal, whether itis triangular, quadrilaterlal, pentagonal, hexagonal, or the like. Accordingly, each of the metallic fibers for use in the antistatic yarn of the invention has several ridges or corners 3 extending longitudinally thereof.
These metallic and nonmetallic fibers are spun intoany of the antistatic yarns illustrated by way of example in FIGS. 1 to 3, in such a manner that the metallic fibers are arranged substantially circumferentially of the aggregate of both types of fibers throughout the length thereof. It is not of absolute necessity that all the metallic fibers be arranged outside of the nonmetallic fibers. The objects of this invention can be accomplished if a substantial part of the metallic fibers are arranged circumferentially of the yarn.
The yarn thus formed in accordance with the novel concepts of this invention prevents the buildup of static electricity as explained hereinbelow. The metallic fibers 1 of polygonal cross section arranged substantially circumferentially of the yarn have the corners 3 which extend substantially longitudinally of the yarn and which are either exposed or buried under the yarn surface. Hence, as static electric charges are built upon any part of the yarn, the relatively sharp-edged corners 3 of the metallic fibers I quickly collect the charges and dissipate the same throughout the length of the yarn. In case most of the metallic fibers are exposed on the surface of the yarn, as for example in FIG. 1 or 3, they will be additionally effective to dissipate the charges built up on the surfaces of other yarns in contact therewith. It will now be apparent that the concentration of electrostatic charges and the resultant sparking thereof are successfully prevented due to the metallic fibers 1 of polygonal cross section arranged substantially circumferentially of the yarn throughout its length.
Metallic fibers are generally of higher specific gravity than nonmetallic fibers. Moreover, if such metallic fibers are arranged linearly along the length of a yarn, they will not usually favorably unite with the nonmetallic fibers also employed to form the antistatic yarn. According to this invention, however, the metallic fibers 1 each have a plurality of relatively sharp-edged corners 3 which serve substantially to bind the metallic fibers to the nonmetallic fibers 2, so that both types of the fibers can be held in a favorable state of cohesion suitable for use as a yarn.
The present invention is hereinafter described more specifically in terms of several embodiments thereof which are intended solely to illustrate and explain, and not to impose limitations on the invention.
EMBODIMENT 1 In the first preferred embodiment of the invention shown in FIG. 1, the metallic fibers 1 of stainless steel or the like each having an approximately hexagonal cross section, and the nonmetallic fibers 2 such as synthetic fibers are combined to form a single yarn 4, in such a manner that the metallic fibers l are arranged predominantly on the circumference of the yarn. Each of the metallic fibers 1 has a diameter of about 8 microns, and each of the nonmetallic fibers 2 has a substantially similar diameter.
EMBODIMENT II In another preferred embodiment of the invention shown in FIG. 2, the yarn 5a has several plies or strands 6 of the nonmetallic fibers 2 arranged substantially centrally, and other plies, each having the metallic fibers l of polygonal cross section arranged circumferentially so as to enclose the nonmetallic fibers 2, are provided substantially on the outside of the centrally-arranged plies 6 of the nonmetallic fibers.
EMBODIMENT lll FIG. 3 illustrates still another preferred embodiment of the invention, in which the yarn 5b has several plies 6 of the nonmetallic fibers 2 arranged substantially centrally so as to be enclosed by plies 1 of the metallic fibers 1. The fibers of the embodiments shown in FIGS. 2 and 3 are finer than those of the FIG. 1 embodiment.
Although the present invention has been shown and described hereinabove in terms of several specific embodiments thereof, it will be easy for those skilled in the art to devise many modifications thereof on the basis of this disclosure. It is therefore appropriate that the invention be construed broadly and in a manner consistent with the fair meaning or proper scope of the appended claims.
I. An antistatic yarn comprising, in combination:
a first plurality of metallic fibers;
a second plurality of nonmetallic fibers;
each of said metallic fibers having a polygonal cross section to have at least one substantially sharpedged corner disposed along substantially the entire length of said metallic fiber, said corner serving to collect static charges formed in said yarn and to dissipate said static charges across the entire length of said yarn, said polygonal cross section serving to enhance binding between said metallic fibers and said nonmetallic fibers; and
said first plurality of metallic fibers and said second plurality of nonmetallic fibers being combined so that a substantial number of said metallic fibers are arranged adjacent the outer periphery of said antistatic yarn.
2. An antistatic yarn according to claim 1, wherein said first plurality of metallic fibers is arranged in a plurality of clusters, and wherein said clusters are disposed adjacent the outer periphery of said antistatic yarn.
3. An antistatic yarn according to claim 1, wherein some of said nonmetallic fibers are arranged in clusters, and wherein each of said clusters is surrounded by a plurality of said metallic fibers.
4. An antistatic yarn according to claim 1, wherein at least some of said metallic fibers are arranged substantially linearly along the length of said yarn.