US2962885A - Elastic garment - Google Patents

Description

Dec. 6, 1960 H. KNoHL 2,962,885

ELASTIC GARMENT Filed June 3, 1959 2 Sheets-Sheet l n. am

ik?? 'l' INVENTOR. H, 1 @2f/@fa aan# Dec. 6, 1960 H. KNol-u. 2,962,885

ELAsTrc GARMENT Filed June 3, 1959 2 Sheets-Sheet 2 IN V EN TOR.

`the invention. double bed V type machines: are suitable systems when United States Patent ELASTIC GARMENT Herbert Knohl, Seneca, S.C., assigner to The Kendall Company, Boston, Mass., a corporation of Massachusetts Filed June 3, 1959, Ser. No. 817,774

19 Claims. (Cl. 66-178) This invention is concerned with very snug-litting sheer streetwear ladies knitted stockings `and with shaped generally tubular stretchable and retractive knitted garments having a plurality of different diameters in .the general .range of fineness and sheerness of ladies streetwear stockings. In particular, this invention is concerned with a .new type of -streetwear stocking and with other generally tubular shaped new type garments with knitted body por- 'tions of very -sheer and fine knit stitches of ne nonelastomeric yarn but incorporating substantially-relaxed yst-retchable, -retractive yarns with major portions thereof `extending coursewise and generally defining, by thelr relaxed coursewisellength, the relaxed shape of .the body portion. In general, the garments of Ithis invention are of the non-rib body portion type which may be knitted :on a s-ingle needle knitting system.

The non-rib body portion `of Vgarments .of this inventions. For example, the conventional circular hosiery machine equipped with vdialsor modified Aclials for knitting rib tops yand automatic .welts iis a suitable needle system for the purpose of this invention. Likewise, lthe flat bed full-fashioned .machine is .a suitablesystem as kused in The Burson knitting machine land lother knitting is `performed ,alternativelyon one needle bed at a time. The invention Valso iapplies to all plain circular knittingmachines suchastsinker top and bodymachines for underwear and outerwear. Links and hnks, ,machines with superimposed cylinders or lflat machines with opposing needle Vbeds may ,also operate as suitable needle lknitting systems.

Heretofore, garments incorporating l,elastomeric yarns have been of several types. V,Mens socks incorporating inlaid vrubber yarns vin the ltop -or rwelt portion (usually ribbed) to provide a garter effect are well known. These garments in .the'portion `where,the rubber yarn is incorpo- .rated are cylindricalin shape anddo not luse the principle of varying the tension -on the rubber thread or variable imetering during manufacture to shape the stocking to fit the different diameters of the leg. Other Vgarments -in- -corporating rubber yarn are full length elastic stockings and girdles which heretofore have been either of heavy Vthick rib knit or open mesh construction with inlaid heavy covered rubber yarns or the more popular plain knit type -with rubber yarns forming Vthe knit stitches. This latter construction has been made of very necovered rubber yarns of the order of 160-core (diameters per Yinch bare). Covered yarns have proven necessary, however, because bare rubber, when it :makes over-all contact with human skin, has a cold, vclammy, unpleasant feel. Covered yarns have .also .proven necessary lfrom a practical standpoint to .add strength because knitted vstitches must bear the strain of :garter-support whichisgreater rice with garments having considerable longitudinal `elasticity and bare rubber is somewhat lacking in iiex strength. Garments of this `type have, therefore, been knitted of rubber yarns having helical windings of nylon or other relatively strong material covering a rubber core. These windings covering even the finest rubber cores in every stitch detract considerably from the hand and trans# parency of the garment and add weight and bulk to it.

Heretofore, tine streetwear ladies stockings, whether of the full-fashioned orvof the seamless type, and whether of normal yarns or of stretch or torque yarns have had the disadvantaget-hat unless they are constantlyrsupported as by garter clamps suspended from a waist encircling garment yand exerting longitudinal pull, they do not properly fit the leg. This longitudinal pull exerted by the garter distorts the stitches longitudinally and thus reduees the width ,of the individual stitches andthe whole diameter Vof the stocking as far as the leg will permit. However, those portions of the stocking where rather continuous exing is not unusual in use, s uch as the ankle or knee portion, progressively stretch locally during extended periods of wear so that at the end of the day the ankle and kneeportions particularly have been distorted to the point where they no longer itv snugly but rather have ka baggy wrinkled appearance.

V,It is one of the objects ,of this invention to provide full streetwear ladies stockings which require a minimum ofgarter support Aand which are of such fineness and stitch density as t0 .appear sossarner and substantially transparent on the leg, yet which l'fit the leg vin all portions thereof.

AIt isanotgher 4object of this invention to provide belowthegknee streetwear stockings which Iare entirely self-supprtng and which are .0f Such frleness and stitch density as toappearlgossamer v`and substantially transparent lon the leg and lrwhichiitthe leg in all portions thereof.

It is a further Aobject of this invention to provide other generally tubular shaped garments which are lself-,supporting and which are of such fineness and stitch/density as to appear gossarner kand substantially transparent when worn Vand which closely contact the body part over Iwhich the garment .is `worn where suehcontact is desired.

vIt is an additional object of this invention to provide various very sheer-elastic circumferentially shaped knitted tubular garments such as stockings, ank-lets,.w,ristlets, knee binders, girdlesand the like, of plain jersey, tuck, or combination knit stitches with bare stretchable, v,retractive yarns at yleast partially shaping the garment to dilferent diameters-with major -portions extending coursewise in the body portionof the knitted fabric and locked-in at frequent intervals.

It is an important object of this invention to produce elastic garments which have knitted stitches of one size with inlaid bare stretchable, `retractive yarn of a given coursewise relaxed Vlength in one area of the knitted body and have knitted stitches of a smaller ,size with inlaid bare elastic yarn of aflesser coursewise relaxed length in another area of the knitted body.

vOther objects and advantages of the invention will be apparent from the following description thereof in connection with the accompanying drawings in which:

Fig. 1 illustrates a side view of a full length ladys stocking of this invention.

. Fig. 2 illustrates a side view of a below-the-knee stocking of this invention.

Fig. 3 illustrates a wristlet made in accordance with this invention.

Fig. 4 illustrates a shaped knee binder madein accordance .with this invention.

Fig.. 5 illustrates a step in the method of vmaking a garment of this Ainvention on a lfull-fashioned knitting making a garment of this invention on a full-fashioned knitting machine and an enlarged portion of an alternate type of fabric of this invention viewed from the inside.

Fig. 7 illustrates an enlarged view showing the method whereby the retractive yarn is inlaid on a full-fashioned machine.

Fig. 8 illustrates a step in the method of making a garment of this invention on a seamless circular knitting machine and an enlarged portion of the preferred type of fabric of this invention formed as viewed from the inside. Y

Fig. 9 illustrates the apparatus by means of which the retractive force or support pressure in millimeters of mercury of a garment of this invention is measured while the garment is being worn.

Referring now to the drawings.

Fig. l illustrates a side view of an ultra sheer streetwear ladys stocking 10 of this invention including a knitted body portion 11 wherein bare retractive yarns are normally incorporated, a top 12 including a turned welt, preferably of the automatic type, usually of heavier nonelastic yarns, a heel 13 and a toe 14. The latter portions and the top 12 may be of any of the materials normally used for similar purposes in streetwear stockings.

Fig. 2 illustrates a very sheer self-supporting belowthe-knee stocking 20 of this invention which may be worn by either sex. Again the stocking consists of aknitted body 21 wherein bare retractive yarns are incorporated. TheV top of this stocking may consist of a turned welt of heavier non-elastic yarn or a turned welt of the` same material including Vretractive yarns as the body or the top may merely be an unturned continuation of -the body with modified stitch or inlay construction. In Fig. 3 a sheer stocking fabric wristlet 30 has a knitted body portion 31, a bottom welt 33 and a top Welt 32. The entire garment may be of similar material incorporating bare retractive yarn with or without turned Welt. If desirable, the end portions may be left plain and overedged.

In Fig. 4 the very sheer stocking fabric knee binder 40 has a shaped knitted body 41 incorporating a retractive yarn and turned welts 42 and 43 may be of the same or different material. Alternatively, the ends may be left plain and overedged. Shaped articles where the axis of the tube is curved, such as the knee binder 40, may be made using a panel of tuck stitches in the under knee portion and plain jersey stitches in the front portion. The retractive yarn might be inlaid in every course of the tuck stitch panel and in alternate courses of the jersey stitch portion. Alternatively, the binder 40 may be made in the form of a truncated conical tube of plain knit stitches of thermoplastic yarn with inlaid thermoplastic elastomeric yarn. Localized shaping, curving the tube axis may be achieved afterwards by preboarding as will be explained hereinafter. Combinations of these two methods may also be advantageously utilized.

In Fig. a step in the method of making a fullfashioned very sheer garment of the invention is illustrated. The sinkers 53 place the retractive yarn 52 which is furnished by a separate carrier against the Shanks of the iised needles on the hook side. Above the alternate needles 56, picot points 55 descend to close the beards. The retractive yarn, carried in the notch of the sinkers, is fed into the hooks of the unclosed intermediate needles. 57, and against the picot points at the alternate needles as the needles are depressed. When the sinkers are withdrawn and the needles depressed further, the'retractive yarn lies in the hooks of the intermediate needles 57 and against the beard of the alternate needles 56. As the needles are further depressed, the retractive yarn rests above the alternate needles on the knock-over bits and in the hooks of intermediate needles. At this point, the

picot points are depressed again to close the alternate needles thus causing the retractive yarn to pass behind the alternate needles when the needles are raised, whereupon the retractive yarn lies against the needle Shanks in front of the intermediate needles and behind the alternate needles. At this point, illustrated in Figure 5, the picot points are shifted to positions 54. The knitting operation follows the retractive yarn positioning operation as will lbe explained in connection with Fig. 7. When the picot points are in the positions S5, the retractive yarni is positioned with respect to the needles as is illustrated in Fig. 5, andthe retractive yarn is laid into the fabric as at b. When, however, the picot points are in position S4, the retractive yarn 52 is positioned on the opposite side of each needle from the position illustrated and, consequently, the retractive yarn is laid into the fabric as at a. It will be noted that preferably a portion of knitted fabric without inlaid retractive yarn exists at the garment blank edges. This fabric may conveniently be used in making a thin seam.

In Fig. 6 is illustrated a further step in the method of making a full-fashioned garment of this invention. It will be noted that the fabric 60 has a retractive yarn 62 inlaid only in alternate courses, but on the full-fashioned machine this may be accomplished by taking the retractive yarn carrier out of action on alternate courses. The figure illustrates the placing of the knitting yarn 61v in the hooks of the needles 65 by the sinkers 63. The4 picot points 64 which always operate on the same needle in this case operate in the way previously explained to` position the retractive yarn prior to the knitting operation.

Fig. 7 illustrates the needles 65 in the process of draw ing a new loop of yarn 61 shown in the hooks of the needles through the old loops. The beards of the needles are closed prior to contacting the old loops and the retractive yarn by contact with the presser bar as the needle descends as in ordinary full-fashioned knitting. The fabric is similar to that shown in Fig. 6 except that retractive yarn in fabric 60 is inlaid in every course.

In Fig. 8 is illustrated a method of making a preferred garment of this invention on the circular machine. Fabric 80 consists of knitted yarn 81 with retractive yarn 82 inlaid in every course. In the method, alternate needles are partially raised to take the retractive yarn 82 in the alternate needle hooks and pull it down, whereupon the sinkers push the retractive yarn over and beyond the intermediate needles are illustrated. As the needles rise to take knitting yarn in theirhooks, the retractive yarnY being held down by the sinkers cannot rise. The retractive yarn, therefore, slides relatively over the latches on the Valternate needles and down and in front of the Shanks. At the same time the retractive yarn slides relatively down and behind the Shanks of the intermediate needles. When the needles retract to form new loops and cast olf the old loops, the retractive yarn in front of the alternate needles is also cast off.

In Fig. 9 is illustrated the apparatus 90 by means of which the retractive force or support pressure in millimeters of mercury of a garment of this invention is measured while the garment is being worn or is stretched on a form. A manometer 91 is graduated to indicate pressure in millimeters of mercury. The manometer is attached by a rubber hose 93 to a three-way stop cock 92 to which is attached the hose 95 and the glass syringe 96 graduated in cubic centimeters. Hose 95 is in turn attached to a hypoderrnic needle 94, the needle end of which has been cut oft to make a short hollow projection. This needle projection in turn ts into a size 8 venereal catheter 97 which carries on its end a at rubber bladder 98 each of whose flat faces has an area of about one square inch. The whole arrangement is made airtight. Upon being Vinflated with 5 cc. of air, using the glass syringe, the bladder should be of such modulus as to exert about 20 mm. of mercury pressure as measured on the manom? eter. I find that the rubber sheeting in ordinary surgeons essere gloves has characteristics permiting bladders of the type described to be made.

The objects of this invention are attained by the incorporation, into the very sheer non-rib body portion fabric of ne knit garments, of bare retractive yarns in such a way that the sheerness and gossamer appearance of the garment are not destroyed, although shaping to a plurality of different diameters is achieved. This preferably can be accomplished in accordance with the invention by the use of bare retractive yarns-which are incorporated so that major portions ofthe retractive yarn extend coursewise of the fabric, preferably by being inlaid in every course, but in any event being locked into the fabric at frequent intervals in every course in which it occurs.

The stretchable, retractive yarns (sometimes herein referred to merely as retractive yarns) included in the garments of this invention are preferably of natural rubber, synthetic rubber or other elastomer. Certain polymers and/or copolymers including, but not restricted to, those of the polyamide (nylon), polyurethane, halogenated polyethylene and polyvinyl types may exist either in elastomeric or non-elastomeric form depending on the choice of monomers or reactants, the nature or degree of polymerization, the presence of plasticizers, or the use of other methods or techniques well known to the art. One such elastomeric yarn, believed to be of the polyurethane type, is manufactured by E. I. du Pont & Co. and sold under the name Fiber K. This yarn is highly suitable as the elastic retractive yarn employed in the garments of this invention.

I may also employ retractive yarns of non-elastomeric materials, which yarns have elastic properties because of their method of manufacture, arrangement or physical, chemical or other treatment, as the stretchable, retractive yarns in the garments of this invention.

Preferably, relatively little elastomeric yarn appears in stitch form and then never as the sole yarn in the products of my invention. In most commercial garments of my invention, less than 20% of the knitted stitches in the body portion of the garment contain such yarn, and these stitches also contain the normal structural yarns of the garment in plated or other knitted relationship in the same stitches with the elastomeric yarns so as to minimize the strain on the latter yarn. Such knitted elastomeric stitches have the effect of increasing the tendency of the garment to pull down since the elastic yarns are in stretched condition when the garment is being worn. Furthermore, knitted elastomeric stitches have the effect of decreasing the apparent transparency (transmitted light factor as hereinafter explained) of the garment. Both of these effects are undesirable and are accentuated as the total bulk of knited elastomeric yarn in the knitted stitches is increased. When the percentage of stitches in the garment which include elastomeric yarn exceeds about 70%, the advantages of my invention are so far dissipated that the garments have little in common with my preferred structures. This percentage will be somewhat less with relatively coarse elastomeric yarns and somewhat higher with relatively ne elastomeric yarns however.

The preferred stockings of the present invention, therefore, are characterized by the fact that they are substantially free of elastomeric yarns in the knitted stitches, the bare elastic yarn being incorporated by inlaying into the knitted body courses to provide a plurality of diameters which determine tit and/or pressure support primarily in the circumferential direction. Concentration of the elastomeric yarn in the inlay produces a stocking. in which the circumferential elastic and retractive properties are largely distinct from the lengthwise elastic properties so that, while the stocking may have considerable elongation in the lengthwise direction, the preferred stockings do not have a strong component of retractive force when stretched in this direction. Thus, the stockings are.

' tions of elastomeric yarn which are formed into knitted stitches in the body of the garments of this invention are advantageously in plated relationship or are otherwise. knitted in the same stitches with other non-elastomeric yarns such as nylon, which limit the stress and strain on the elastomeric yarn. In any event, whether the stretch-l able retractive'yarn is elastomeric or derives its elastic properties from kits physical arrangement or other means,

it is always separately incorporated in the body portion ofV the garment, so that the structural network of the knitted stitches is not dependent upon the retractive yarn. Thus, alhough the retractive yarn which runs in a generally coursewise direction may sometimes be included in a knitted stitch as hereinbefore described, a non-elastomeric yarn of the knitted structural network is always present in the same stitch. Consequently, if the elastic yarn is snaggedv or broken, whether in the stitch or elsewhere, its free ends do not cause a so-called run Rather, the free ends are locked in place at frequent intervals by the extremely tine body stitches (which are characteristic of the garments of this invention) and in the case of inlay yarn, by. the over and under pattern; whereby the function and appearance of the stocking are substantially un-iv impaired.

Withregard to functionality, the garments of this invention also vary greatly. They may merely provide a snug fit in some cases; or with garments of greater retractive force, they may provide support for so-called tired legs. Garments possessing still greater retractive force may furnish compressive support `for Weak or sprained joints or provide support and treatment for varicose conditions. In any event, all of the garments have these things in common, they have ultra-sheer body portions and they each incorporate in the body portion bare retractive yarn with major portions extending coursewise which shape the body portion to a plurality of diameters and cause it, when worn in the stretched condition, to exert retractive force tending to reduce the diameter of the vbody portion.

rfhe fine knitted stitches of the body portion of the preferred stockings of this invention largely determine the lengthwise stretch of the garment, Every such stitch contains line structural yarn of such non-elastomeric natural or synthetic materials as nylon, silk and the like. Yarn of elastomeric material such as natural and synthetic rubber lacks sufficient strength, toughness and abrasion resistance for use as a structural yarn unless it is so coarse as to add bulkiness, thus sacrificing the sheerness and appearance of transparency characteristic of the garments of my invention.

The structural yarns used in the body portion may be of the same material or of different material in different courses. Some courses may be of short stitches while other courses are of relatively long stitches or the individual stitches may vary in size. The yarns may be of balanced twist or they may be twisted with an unbalanced twist in either the S or Z direction. They may consist of stretch and/or torque S and Z twist in alternate courses or in other course relationship or the individual stitches may each contain an..S and a Z twist yarn in plated relationship or either of these torque or twist yarns plated with'stretch yarns. The yarns of the knitted stitches may be of the Helenca type wherein the multilament yarns are kinked and deformed and set in that condition by heat. Or the yarns may be of the inherently lively type whichY are `knitted as non-lively yarns, bu

which upon being subjected to a heat treatment becomeV lively. Likewise, combinations of these and plain yarns wales preferably spaced and preferablyin dilerent Wales in adjacent courses. This may be done as is illustrated yarn is plated 1n the individual stitch with the knitted yarn. This method produces a durable stocking since where the yarn is elastomeric it is not subjected to longitudinal force beyond its elastic range. However, where there are long floats between retractive knitted stitches, I prefer to inlay the retractive yarn between knitted retractive stitches.

The knitted yarns of the stockings of this invention may vary in diameter corresponding to nylon yarns of 7 denier and less to 60 denier and of tensile strength such that when knitted into the high stretched-stitch density stockings of this invention, the fabric will have a bursting strength, when constructed of the nest yarns, of at least pounds per-square inch measure on the Mullen tester.v Where full therapeutic support is provided, however, a

bursting strength of at least 30 pounds per square inch is preferred.

The garments of this invention are preferably knitted either on full-fashioned machines or on circular machines. Suitable full-fashioned machines are those in the range of 45 to 90 gauge with 30 to 60 needles per inch. Suitable circular machines with 31/2 to 6 inch diameter cylinders for stockings and other circular machines up to 30 inches in diameter are also in the range of 30 to 60 needles per inch, although the highest needle density per inch now available is about 40 on the 4 inch 504 needle or on the 33/4 inch 474 needle circular machine.

The retractive yarn inlaying mechanism and method which may be utilized with the full-fashioned machine may be of the type illustrated in the Gastrich Patent No. 2,185,844 or alternatively the method and device illustrated in the Verbeek Patent No. 2,054,686 or other known methods and devices such as those in the Ruedt Patent No. 2,251,805 or in the Schwartz Patent No. 2,230,388 may be utilized.

The retractive yarn inlayng mechanism and method which may be utilized with the circular machine may be similar to that used in the Getaz Patent No. 2,230,402 or the Page Patent No. 2,083,394 or by other Well known methods such as that described in the Scott Patent No. 1,641,544. Where the desirable needles per inch ratio is extremely high, however, it may be necessary to utilize beard type needles and the knittingsystem corresponding to such needles. A Pigeon type circular knitting machine has been produced with such beard type needles.

In general, it is preferred to inlay the retractive yarns in every course of knitted stitches, but alternatively the yarn may be inlaid only in alternate courses, every third cou-rse or in other variations. Preferably where the retractive yarn is not incorporated in every course, its feed is not removed from operation but the machine is pro'- vided with one or more additional feeding stations for the courses incorporating no bare -retractive yarn.

It is also preferred because of the simplicity of the system and the better shielding of the retractive yarn to inlay the latter behind hooks of alternate needles and in the hooks of intermediate needles. When circular machines of even number needles are used, this system causes the retractive yarn to always have the same position with regard to avgiven wale. When-circular machines of odd number `needles are used with a pattern wheel, the system causes vthe retractive yarn to lie in a staggered arrangement with respect to the wales similar in the Martel Patent No. 2,102,369 where the retractive aceass to the arrangement in Fig. 5 with regard to aV and b. In

this respect, the uniform arrangeme'nnas is illustrated in" Fig. 8, has a more pleasing and uniform appearance.

But pattern drums or jack manipulation may be uti-l lized in the conventional manner to vary the path of the retractive yarn so that it passes on the same side of: more than one needle, thus reducing the points where the retractive yarn is locked-in with the knitted sttchesf However, it must be realized that numerous tie-ins arel helpful in preventing puckering, in protecting the bare yarn against abrasion and snagging and the like.

Because of their high speed constant uniform motion and theV ease of control of the bare retractive yarn which must necessarily be under some tension, it is preferred to utilize circular knitting machines for the products of this invention. In addition to the usual circular knitting Ina-` chines equipped for inlaying, the Reymes-Cole circular machine which permits adding wales and which is illusf trated in U.S. Patent No. 2,703,970 may be equipped with inlaying devices and utilized.

When the full-fashioned knitting machine is utilized, it is preferred to stop the inlaying somewhat short of the edge of the knitted fabric blank on either side, as is illustrated in Fig. 5, thus creating au area with no retractive yarns so that the knitted yarns may be utilized in this area in making a very thin back seam.

The bare retractive yarns of the garment of this invention, whether they are inherently elastic due to their elastomeric nature or are elastic due to treatment, may be very line and yarns as tine as 7 denier and less may be used, both monoiilament and multitilament yarns being suitable.

In comparing the iineness of some of the stockings of this invention with other stockings, the numberV of stitches in a square inch of fabric fully stretched in both directions, hereinafter referred to as the stretched stitch density, is utilized. Heretofore, ladies stockings for street wear have ranged in stretched stitch density from about i350 to 2900 stitches per square inch, while fullyY therapeutic stockings have usually ranged in stretched stitch density from 350 to 700 stitches per square inch. The stockings of this invention are in the stretched stitch derity range of about 1000 to 4000 stitches per square inc 1 Heretofore, there has been necessarily a practical limit to the tineness of the yarns used in streetwear stockings because the knitted fabric must take the tremendous pressure imposed on that portion of the stocking covering the knees when the knees are bent, thereby increas` ing the stocking diameter and the over the knee leg length simultaneously. The stocking is strained to the utmost in attempting to conform to these altered dimenl sions. Because high bursting strengths are necessary in such stockings, l5 denier nylon yarns are universally used. There is a 75 gauge full-fashioned stocking on the market which utilizes 10 denier nylon in the body, but the delicacy of these garments relegates them to the carriage trade. An experimental gauge full-fashioned machine which is capable of knitting even finer Stockings has been used, but its products did not prove to be a commercial success.

There is an additional problem which has caused diif culty with regard to seamless stockings of the usual type. Such stockings have the same number of wales in the top -as are in the angle, and since both have to be fitted, the seamless stocking has been a compromise. The neness of full-fashioned stockings has not been achieved. A 4 inch seamless machine with 504 needles (or about 40 to the inch) appears to be near the practical limit for machine neness using present methods. Increasing the needles per inch or increasing the cylinder diameter causes the ankle to be too loose. The use of torque yarns of alternating S and Z twist yarns have helped this situation, but it is necessary to keep sucli stockings tautly supported if S and Z twist yarnsy are relied upon to tighten the angles.

The stockings of this invention have a definite advantage over previous seamless and full-fashioned stockings in that the retractive yarn tends to reduce the limp cir- 'cumferential dimensions of the finished garment so that it is possible to use more knitted wales in the garment circumference without making it too large. These added wales help in two Ways. They make the fabric stronger and they reduce the strain by reducing the amount each stitch must widen to accommodate the increased circumference of the bent knee, and hence they reduce the amount each stitch must shorten against the pull of the garter clamps. Viewed in another Way, the stockings of ythis invention may be made finer in practical strengths than stockings have ever been made before. The invention permits the use of larger circular knitting machine cylinders and wider full-fashioned stocking blanks or the use of more needles per inch, or both, than have been practical heretofore.

With a given retractive yarn and within its retractive and stretch limits it is possible to vary the limp dimension of any portion of the garment considerably merely by metering into the fabric different amounts of retractive yarn either by tensioning devices or otherwise. Using 20 denier monolament yarn in the knitted stitches Iand inlaying bare 150 denier Fiber K yarn in every course, I produced fabric of the same stretched stitch density (1950 stitches per square inch) on a 3% inch 400 needle circular knitting machine which in one case had a limp circumference of 35/s inches and in another case a limp circumference of 61/2 inches. The larger fabric, which 4had a fully stretched circumference of 17 inches, when placed on a 9 inch circumference ankle induced a pleasant supportive sensation falling in the lower portion of -the therapeutic range with 15 millimeters of mercury pressuresupport measured as will hereinafter be fully explained. The smaller fabric, which had a stretched circumference of 12 inches, had more definite compression higher than the usual therapeutic range when placed on a 9 inch circumference ankle and produced 31 millimeters of mercury pressure-support.

Using 15 denier monofilament yarn in the knitted stitches and inlaying bare 160 core rubber (160 diameters measure one inch) in every course, I produced fabric of the same stretched stitch density (2240 stitches per square inch) on a 3% inch 400 needle circular knitting machine which, in one case, had a limp circumference of k21/2 inches and in another case 7% inches. The larger fabric, which had a fully stretched circumference of 19 inches, when placed on a 9 inch circumference ankle induced a pleasant clinging sensation and produced only millimeters of mercury pressure-support measured as will hereinafter be fully explained. The smaller fabric, which had a stretched circumference of inches, had

more definite compression in the therapeutic range when placed on a 9 inch circumference ankle and produced 20 millimeters of mercury pressure-support.

Pressure-support possessed by a garment may also be changed within limits by varying the stitch size in difierent portions of the garment. It is customary to decrease the stitch size progressively from the top to the ankle of a seamless stocking. It is obvious that where the stitches are shorter, the helical loops of retractive yarn inlaid in the courses are closer together, and hence the pressuresupport resulting from a given tension on a given retrac tive yarn is increased in the area of shorter stitches. This effect, due to variations in `length of stitches, is, however, usually subordinated to the variation in pressure-support caused by the predetermined variation either in metered length or tension on the retractive yarn as it is knitted.

The limp dimensions of the stockings of this invention -depend upon a number of circumstances. Obviously the limp dimensions of a stocking should be such as to make them as easy to put on as circumstances willpermit.

Increasing the sizeof lthe cylinder where circularmachines are used or of the pattern .blank where. full-fashioned machines are used is the most obvious way of increasing the limp dimensions other factors remaining constant. But limp dimensions also vary with the bulk `of the knitted stitch yarns. A bulky yarn will cause the l,limp dimensions to be larger than Va finer knitted yarn. The limp dimensions also may be varied by increasing the needles per inch. A finer gauge full-fashioned machine or a circular machine of greater needle density will give'larger limp dimensions .than coarser machines using the .same course width or the sameV diameter cylinders. nBy .far the greatest factor in determining the Ylimp dimensions of the stockings of this invention, however .'(assuming that the knitted stitches form a garment suficiently'large to accommodate the leg), is the type of inlaid retractive yarn and the conditions under which itis inlaid. For-instance, a yarn having a very low modulus'- of elasticity causes a larger limp'dimension than a higher modulus yarn which is able to draw-in thefabric to a .greaterv degree when both are inlaid with the same elongation. Likewise, short stretch (i.e. up to 300% elongation.) inlaid yarns produce larger fabric than long stretch (ie. up to v600% elongation) inlaid yarns if both are knitted at dead stretch. Similarly, yarn inlaid under tension vwhich elongates it 300% causes limpdimensions larger than when it is inlaid under tension which elongates it 500%. Some of the stockings of this invention provide, for the first time, a new and novel method of .altering the limp dimensions of circumferentially retractable stockings while altering Vbut not destroying the retractable nature of the garment. I have found that where both the knitted lstitchyarns and the elastomeric inlaid yarns are thermoplastic, 'the stocking may be preboarded lto change its limp dimensions dramatically, approaching closely Lbut always smaller than the circumferential `proportions of aparticular size leg to be fitted. For instance, with nylon knitted stitches and Fiber K polyurethane-type inlaid yarns, a fabric with a limp circumference of 4 inches may be stretched over a board and subjected to temperatures in the range'of 260"- 300 F. for 2 minutes to produce a limp circumference of 6 inches. The fully stretched width is only slightly increased by this treatment and the Fiber K yarn appears to be somewhat decreased in elastic modulus' (l5- 20%), but this decrease can be compensated for by using slightly higher elastic modulus yarns initially. In any event, stockings with full therapeutic `support characterf istics' may be produced after preboarding. Alternatively, with thermoplastic elastomeric yarns, the yarn may be given a pretreatment prior to inlaying it into the garment whereby the elastomeric yarn is converted into a shorter stretch, lower elastic modulus yarn and this when inl-aid under the same conditions gives a garment of larger limp dimensions' and reduced support-pressure. My preferred method of pretreating these thermoplastic elastomeric yarns is to draw them at a temperature such that the `yarn is softened but not melted. I prefer to use a ceramic tube heated by a coil of resistance wire. The yarn s run through the tube without contact. With Fiber K poly# urethane-type yarns, I use an inside tube temperature of 340-350 F. and draw .the yarn about 160% at a take-up speed of 7 yards per minute. The yam produced has about 1/2 the elastic modulus and total stretch and about 1/2 the cross sectional area of the 'original yarn. It is very uniform. This process may be repeated preferably by tandem methods until a -very low modulus, short stretch yarn is produced. 4

With regard to transparency, the garments of Vthis invention are most transparent when they are made .of` un.-

filled and undyed yarns. Dyeing ysuch garments some` what diminishes the apparent transparency, tparticularly in the darker shades. In order to eliminatefthe effect of dyeing and filling, all measurements .of transparencies were taken on uniformly dyed beige stockings made unfilled yarns. Using a watt frostedt light bulb wil 1-1 a transparent form, a light meter placed 14 inches from the bulb gave a reading of 30 foot candles without stocking fabric on the form. Normal 15 denier beige street wear stockings in the range of stretched stitch densities of 1500 to 2200 stitches per square inch when placed on the form under the same conditions gave readings of transmitted lights of 27 to 29 footcandles. For purposes of this invention, the transmitted light factor will be expressed as a fraction, with the denominator as 30 and the numerator the transmitted light in foot candles through the form and stocking. Beige stockings of this invention of 7 denier nylon yarn in the knitted stitches with 7 denier Fiber K polyurethane-type yarn inlaid in every course to give a slight clinging action to the stocking when worn, and with a stretched stitch density averaging 2400 stitches per square inch, have a transmitted light factor of 29/ 30 under these conditions. Beige stockings 'of this invention of A7 denier nylon yarn in the knitted stitches with 300 core bare rubber yarn inlaid in every 'course to give a slight clinging action to the stocking when worn, and with a stretched stitch density averaging 2400 stitches per square inch, had a transmitted light factor of 27/ 30 under the same conditions. Other beige stockings of this invention of higher denier knitted yarns and of greater retractive force ranging up to and including full therapeutic range have transmitted light factors of 20/ 30 to 29/30 under the same conditions. Theriinest elastic stockings available prior to this invention have a range of about 9/ 30 transmitted light factor for fully therapeutic stockings. So-called tired leg non-elastomeric stockings made from alternate S and Z twist yarns of heavy denier nylon have a transmitted light factor of about 20/ 30. e It should be understood that while the preferred garments of this invention employ yarns which are filled or vdyed only to a minor degree, kso as to provide maximum transparency, in other embodiments of my invention the yarns may be opaque and/or dyed to dark shades reducing the transmitted light factor, but preserving a sheer, light-weight garment.

With regard to pressure-support, one very effective method of measuring such support is to utilize a mercury manometer, of the type used for measuring blood pressure, modified as in Fig. 9. In actual practice the instrument bladder is inflated with cc. of air using the glass syringe, whereupon the bladder inflation presure is measured. Then the uninflated bladder is` placedrbetween the stocking and the wearers leg, again inflated with 5 cc. of air and the pressure read. The difference between this latter reading and the bladder inflation pressure is the pressure-support in mm. of mercury as that term is used in this application. I have found in over 20 years of experience in the business of manufacturing elastic stock-ings that presure-supports, as above measured, in the range of 15-24 mm. of mercury a-t the ankle and diminishing gradually l-2 mm. each in the calf, the knee and the thigh are entirely satisfactory for therapeutic stockings. l'In pressure-support ranges short of therapeutic support and of about 10-15 mm. of mercury, stockings of this invention are suitable in relieving the condition commonly known as tired legs. -In this range, stockings of the invention are also suitable as leg slimming devices acting to 'firm the legs in the same way that an elastic girdle reduces the prom-inence of the derriere.

A further range of useful garments of this invention exists in the pressure-support range below 10 mm. and down to about 5 mm. of mercury. This range of pressure* support provides a definite pleasant clinging sensation in sheer stockings which causes the stocking always to fit the leg with a minimum of garter pull. in this range, extremely fine, perfectly tting stockings may be provided with what would ordinarily be so many wales that the stocking would be too large both in the ankle and in the knee but which, in this instance, provide suicient extra tensile strength at the knee to make stockings of hitherto 'impractically fne yarn, entirely practical. Ninetygauge ananas-'8 stockings made of 7 denier yarns are practical garments when made in accordance with this invention.

Ultra-sheer garments other than stockings can be made in Vaccordance with his invention in the same ranges of pressure-support and with the same transmitted light factors as stockings which were chosen for purposes of illustration only.

Typical garments made in accordance with this invention were knitted as follows:

Example I Using the 474 needle 3% inch cylinder knitting machine known to the trade as the Scott and Williams model KN machine, a 60 denier, preshrunk, multitilament yarn with l0 turns of S twist was used for making the turned automatic welt with vthe stitch cam set to produce a stretched fabric of about 26 inches circumference. Upon comple'- tion of the welt, the 60 denier nylon yarn was removed from action and the shadow welt was begun, the feed furnishing 40 denier multiilament nylon with 7 turns Z twist plated over 20 denier multiiilament nylon with 7 turnsy S twist. `In the last course of the shadow welt an additional inlay feed was introduced and about 91/2 inches limp of 75 denier Fiber K polyurethane-type yarn with 600% stretch was inlaid in every course. When the last shadow course was complete, its yarns were replaced by the leg body yarn which was a 20 denier multilament nylon yarn with 30 turns of S twist. At this point, the measured length of Fiber K yarn inlaid in each course was gradually decreased by increasing the tension until at a point about 41/2 inches below the shadow welt it measured 8% inches per pound. Thereafter the amount of Fiber K yarn inlaid in a course remained constant to a point about a foot below the shadow welt. At this point, therstitch cams which previously had been producing stretched fabric measuring 26 inches in circumference began to reduce the stitch size at a constant rate until the ankle was reached about 29% inches from the stocking top at which point the stretch circumference was 16 inches. Simultaneously, the inlaid Fiber K yarn in each course was gradually reduced until at the ankle about 51/2 inches of polyurethane yarn was laid in a round. Both the knitted fabric and the Fiber K yarn were kept constant from this point until the heel was reached whereupon the Fiber K yarn was withheld and 60 denier nylon multilament yarn with 10 turns S or Z twist was substituted for the 20 denier body nylon yarns. AThe heel was knitted automatically by reciprocation on part of the needles after which the body yarn and Fiber K yarn were again introduced and knitting proceeded to the toe. At this point, the body yarn and the Fiber K yarns were removed from action and the body yarn was replaced by 60 denier multitilament nylon with l0 turns S or Z twist. Afterwards, the open toe was closed by looping across the toes under the foot. The stocking above produced was pre-boarded at 280-300 F. for 2 minutes to give a stocking measuring 111/2 inches in circumference above the knee, 9 inches in the calf and 5]/2 inches in the ankle and a length of 2S inches from top to heel and was dyed light beige at 212 F. It had a light transmission factor as measured by the herein explained method of 26/ 30, a stretched stitch density averaging 2000 stitches per square inch and a bursting strength of about 38 pounds per square inch. The pressure-support of this garment when measured by the method explained herein and on a medium sized leg was 20 mm. of mercury in the ankle, 19 mm. of mercury in the calf and 17 mm. of mercury in the lower thigh.

Example Il Using the same 474 needle 33/4 inch cylinder knitting machine used in Example I, a 60 den-ier, preshrunk, multifilament yarn with l0 turns of S twist was used for making the turned automatic welt with the stitch cam setto produce a stretched fabric of about 28 inches circuniference. Upon completion of the welt, the 60 denier nylon yarn was removed from action and the shadow welt was begun, the feed furnishing 40 denier multitilament with 7 turns Z twist plated over 20 denier multiflament nylon with 7 turns S twist. In the last course of the shadow welt an additional inlay feed was introduced and about 81/2 inches limp of 160 core bare rubber yam pig'- mented beige with 600% stretch was inlaid in every course. When the last shadow course was complete,- its yarns were replaced by the leg body yarn which was-a 20 denier multitilament nylon yarnwith 30 turns of S twist. At this point, the measured length of bare rubber yarn inlaid in each course was gradually decreased until at a point about 41/2 inches below lthe shadow welt it measured 8 inches per round. Thereafter the amount of bare rubber yarn inlaid in a course remained constant to a point about a foot below the shadow welt. At this point, the stitch cams which previously had been producing stretched fabric measuring 28 inches in circumference began to reduce the stitch size at a constant rate until the ankle was reached about 291A inches from the stocking top at which point the stretched circumference was 18 inches. Simultaneously, the inlaid bare rubber yarn in each course was gradually reduced until at the ankle about inches of bare rubber yarn was laid -in a round. Both the knitted fabric and the bare rubber were kept constant from this point until the heel was reached whereupon the bare rubber yarn was withheld and 60 denier nylon multilament yarn with turns S or Z twist was substituted for the 20 denier body nylon yarns. The heel was knitted automatically by reciprocation on part of the needles after which the body yarn and bare rubber yarn were again lintroduced and knitting-proceeded-to the-toe. At this point, the body yarn and the bare rubber yarn -were removed from action and the body yarn was replaced by 60 denier multilament nylon with 10 turns S or Z twist. Afterwards the open toe was closed by looping across the toes under the foot. Alternatively, after the heel has been completed and the bare rubber is again introduced it may be desirable gradually to reduce the tension on the bare rubber yarn to the point where the bare rubber yarns are removed for the toe at which point a round of inlaid bare rubber might measure 7 inches. The stock-ing above produced was dyed light beige at a temperature ranging from 180-212" F. It had a light transmission factoras measured by the method explained herein of 2-4/30, a stretched stitch density averaging 1900 stitches persquare inch and a bursting strength of 38 pounds per square rinch. The pressure-support of this garment when measured by the method explained herein and on Ia medium sized leg was l1 mm. of mercury in the ankle, 10 mm. Vin the calf and 9 mm. of mercury in the lower thigh.

Example Ill A stocking was knitted using the same yarns and procedure as in Example II except that the tension on the bare rubber thread was increased so that in the last course of the shadow welt where the bare rubber is first introduced, the limp circumference was 51/2 inches. The limp circumference was gradually decreased to a point about 41/2 inches below the welt where it was 51A inches. The limp circumference remained constant from this point to a point about a foot below the shadow welt at which point it was gradually decreased to the ankle where `it measured 3% inches. This stocking had a light transmission factor of 25/ 30. The pressure-support was 20 mm. of mercury in the ankle, 19 mm. in the calf and 18 mm. in the lower thigh. In other respects it was very similar to the stocking of Example Il. lf a ared foot section is desired for the stocking of Example III it may be produced by gradually reducing the tension on the bare rubber after the heel is knitted so that the garment, at the point where the toe yarns replace the body yarns, measures 4 inches limp.

It will be noted that the above method which is preferred for knitting on circular machines, utilizes the prin- 5'14 ciple of reducing the size of the vknitted stitches and also metering less retractive yarn or increasing the tensionon the retractive yarn in the same portion of the fabric. This procedure reduces both the stretched circumference and the limp circumference.

It is possible, of course,.to produce a circular knit garment in which the stitch size is held constant and-the variation in tension on the retractive yarn does all of the garment shaping. A garment of this type may have all ofthe desired variations in pressure-support but due to excessive fabric in the narrower portions, such as .the ankle of a stocking, the garment may appear more dense in thenarrower portions than in the wider portions.

This application is a continuation-in-part consolidation of my application, Serial No. 740,628, tiled I une 9,1958, and of my application Serial No. 769,654, filed October 27, 1958, which in turn was a continuation-impart of my application Serial No. 740,627, tiled June 9, 1958, alt three of which former applications have now been abandoned.

I claim:

1. A knitted garment comprising a shaped, generally tubular, circumferentially stretchable and retractive nonrib knitted body portion having a stretched stitch density' in excess of 700 stitches per square inch and having a plurality of different diameters generally corresponding to the contours of a portion of the human form and formed primarily of fine non-elastomeic yarn, such as nylon, silk or the like, knitted in every stitch ot said portion and incorporating substantially throughout said body portion at least` one substantially relaxed tine, bare, stretchable, retractive yarn defining the relaxed shapeot' said body portion and having the major portion thereof extending coursewise of, and locked in, said knitted b'o'dy at frequent intervals in every course in which it occurs, said stretchable and retractive yarn being in sutlicient courses of the body so that when the body portion is in a stretched condition around a part ot the human form of different diameters, it exerts a definite predetermined retroactive force upon each portion of the part.

2. A shaped, generally tubular, circumferentially stretchable and retractive knitted garment comprising a non-rib knitted body portion having a stretched stitch density in excess of 700 stitches per square inch and having a plurality of different diameters generally' corresponding tothe contour of a portion of the human form and formed primarily of tine non-elastomeric yarn,`.such as nylon, silk or the like, knitted in every stitch ot' suid portion and incorporating substantially throughout said body portion at least one substantially relaxed fine, bare, stretchable, retractive yarn deiining the relaxed shape of said body portion and having the major portion thereof inlaid coursewise of, and locked in, said knitted body at frequent intervals in every course in which it occurs, said stretchable and retractive yarn being in suicient courses of the body portion of the gament so that when the body portion is in a stretched condition around a part of the human form of different diameters, it exerts a definite predetermined retractive force upon each portion of the part.

3. 'I'he garment of claim 2 wherein the stretchable, retractive yarn is non-elastomeric.

4. The garment of claim 2 wherein the stretchable, retractive yarn is elastomeric and wherein less than about 20% of the stitches of said knitted body portion contain elastomeric yarn in plated or other knitted relationship with the non-elastomeric yarn of the stitches.

5. A shaped, generally tubular, circumferentialy stretchable and retractive knitted garment comprising a non-rib knitted body portion having a stretched stitch density in excess of 700 stitches per square inch and having a plurality of diferent diameters generally corresponding to the contours of a portion of the human form and formed primarily of tine non-elastomeric structural yarn knitted in every stitch of said portion and incorporating substantially throughout said body portionV at least one substantially relaxed tine, bare elastomeric yarn defining the relaxed shape of said body portion and having a major portion thereof extending coursewise of, and locked in said knitted body at frequent intervals said stretchable and retractive yarn being in sufficient courses of. the body portion of the garment so that when the body portion is in a stretched condition around a part of the human form of diierent diameters, it exerts a denite predetermined retractive force upon each portion of the part. 6. The garment of claim 5 having a knitted body portion with a stretched stitch density in excess of 1000 stitches per square inch.

7. The garment of claim 5 wherein the elastomeric yarn is thermoplastic.

8. The garment of claim 5 wherein the .elastomeric yarn is a rubber.

'9. The garment of claim 5 wherein the elastomeric yarn is of the polyurethane type.

10. The garment of claim 5 wherein the non-elastomeric structural yarn is nylon yarn.

1l. The garment of claim 5 wherein the elastomeric yarn is knitted at frequent intervals in the same stitches with stitches of the non-elastomeric structural yarn of the knitted body portion.

12. The product. of claim 5 wherein the garment is a stocking.

13. The product of claim 10 wherein the garment is capable of providing therapeutic suppot.

l ,14. The product of claim 5 wherein :open at both ends. 15. The garment of claim 5 wherein the knitted body portion is seamless.` y

16. The garment of claim 5 wherein the knitted body the garment is portion is seamed longitudinally. 17. The garment of claim 5 wherein the elastomeric tially' relaxed film, bareelastomeric yarn detining the relaxed shape of said body portion and having the major portion thereof inlaid coursewise of, and locked in, said knitted body at frequent intervals in every course in which it occurs, said stretchable and retractive yarn being in sufiicient courses of the body portion of the garment so that when the body portion is in a stretched condition around a part of the human form of different diameters, it exerts a definite predetermined retractive force upon each portion of the part.

- 19. A knitted garment comprising a shaped, generally tubular, circumferentially stretchable and retractive nonrib knitted body portion having a stretched stitch density in excess of 700 stitches per square inch and having a plurality of diierent diameters generally corresponding to the contours of a portion of the human form and formed primarily of tine non-elastomeric yarn, such as nylon, silk or the like, knitted in every stitch of said portion and-having substantially throughout said body portion at least one substantially relaxed tine, bare, stretchable, retractive yarn detining the relaxed shape of said body portion and separately incorporated there in vindependent of the knitted structural network of said body portion in the sense that a break in said retractive yarn will not cause a run in the non-elastomeric knitted body portion, said stretchable, retractive yarn having major portions thereof extending coursewise of, and locked in, said knitted body at frequent intervals in every course in which it occurs, said stretchable and retractive yarn being in suicient courses of the body portion of the garment so that when the body portion is in a .stretched vcondition around a part of the human form of different diameters, it exerts a definite predetermined re- .tratcive force upon each portion of the part.

2,040,965 Verbeek May 19, 1936 2,054,686 Verbeek Sept. 15, 1936 2,161,250 Getaz June 6, 1939 '2,161,868 Kienel et al. June 13, 1939 2,230,388 Schwartz Feb. 4, 1941 2,251,805 Ruedt Aug. 5, 1941 2,306,246 Davis Dec. 22, 1942 2,313,446 lawson Mar. 9, 1943 2,357,506 Davis Sept. 5, 1944 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No. 2,962,885 December 6, 196

Herbert Knohl It is hereby certified that error appears in the above numbered pai ent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 26, after "ull" insert. me length column 3, line 64, for the indistinct word before "needlesf' read raised column 4, line 47, for "are" read M as column 5, line l, for "permiting" read permitting LN; lir 53, for "knited" read knitted column 6, line 22, for "alhough" read although column 9, line 2, for "angles read ankles column ll, line 7, for "lights" read light line 45, for "presure" read me pressure m1; san column ll, line 53, for "presure-supports" read e pressure supports column l2, line 4, for "his" read --1 this mm; line 32, for "pound" read round column 13, line 3, after "multifilament" insert m nylon column l4, line 2 for "non-elastomeic"read non-elastomeric me; line 40, "retroactive" read retractive same column 14, line 56, for "gament" read garment u=-; column l5, line 29, fol the claim reference numeral "lO" read ml2 ma; line 30, foi "suppot" read support mr same column l5, line 42, for "eguare" read square column 16, lines 33 and 34, for "retrateive" read retractive me Signed and sealed this 18th day of April l96l (SEAL) Attest:

ERNEST we SWIDEE DAVID L. LADD Attesting Officer Commissioner of Pate

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