US 3028279 A
Description (OCR text may contain errors)
April 1962 G. HEBERLEIN 3,028,279
UPHOLSTERY MATERIAL Filed April 4, 1958 INVENTOR GEO/PG HEEE/PL El/V.
ATTO R N EYS.
United States Patent 3,028,279 Patented Apr. 3, 1962 iifice 3,028,279 UPHOLSTERY MATERIAL Georg Heberlein, Wattwil, Switzerland, assignor to Heberlein Patent Corporation, New York, N.Y., a corporation of New York Filed Apr. 4, 1958, Ser. No. 726,551 Claims priority, application Germany Apr. 11, 1957 5 Claims. (Cl. 154-48) This invention relates to an elastic material embodying a textile fabric and a foamed rubbery material. More particularly it relates to a composite elastic material with an upper surface comprising a textile fabric fashioned at least in part from crimped, elastic, synthetic yarns and a lower portion comprising a foamed rubbery composition, which composite material is well suited for use as an upholstery material.
Foamed latex and similar foamed synthetic rubbery materials are currently finding wide application in the upholstery field particularly in automobiles, railway cars and the like. However, it is well known that the foamed materials become fatigued to a certain extent when repeatedly compressed as in normal use, and while resiliency remains substantially unimpaired, the foamed material does contract somewhat and its overall dimensions become somewhat smaller.
Normal upholstery fabrics are for the most part woven materials which do not stretch, but which retain their original dimensions fairly well in use. Therefore, as the underlayer of foamed rubbery material becomes some what smaller through use, the covering fabric, since it is incapable of contracting, no longer lies flat on the foamed rubber foundation, but is seen to pucker. This situation ultimately exists whether or not the normally inelastic upholstery fabric is bonded to a thin sheet of foamed rubber or simply applied over an independent foamed rubber foundation.
. It has been suggested to bond sheets of foamed rubber to fabrics fashioned of inelastic yarns but which fabrics are, nevertheless, capable of being stretched to a limited extent as a result of their construction. For example, knit and warp knit goods are somewhat stretchable by reason of the particular loop configuration imparted to the yarns during formation of the fabric, as distinguished rom a normal woven fabric. Stretching in knit goods is the result of longitudinal or lateral elongation of the loop structure. Thus, bonding a foamed rubbery material to a tricot or jersey fabric produces a composite material which may be stretched to a certain extent during upholstering so as to conform better to curved or contoured surfaces. However, fabrics which are stretchable by reason of their particular method of construction exhibit only a slight and distinctly limited stretch. A part of this limited stretch is utilized in conforming the composite material to the desired contour during its application to upholstery. This leaves an inadequate residual stretch in the fabric portion of the composite which is necessary during use of the upholstered article. Furthermore, the longitudinal or lateral elongation of the loops in fabrics made of inelastic yarns places an undesirable strain in the plane of adherence between the inelastic yarn pattern and the elastic foamed rubber layer.
I have found that not only is the residual stretch after application greatly improved by the use of a similar weight woven fabric fashioned of crimped stretchable yarns but the strain in the plane of adherence is substantially eliminated. A knit fabric fashioned of such yarns is vastly more elastic and resilient than the same fabric knit with non-stretchable yarns, and does not tend to pucker.
In order to overcome the puckering problem which arises through repeated use of a chair orother article upholstered with an underlayer of foamed material an upholstery fabric must be chosen which is capable of contracting as required to avoid slack or puckering as the underlayer of foamed material contracts. This ability to contract is inadequate in materials using fabric made of inelastic yarns, knit or otherwise, because to adequately provide for contraction the non-elastic yarn portion has to be stretched to a degree which very substantially reduces the residual stretch of the composite material.
In accordance with the present invention there is provided a textile fabric fashioned at least in part of wholly synthetic crimped yarns which impart elasticity thereto. With the fabric stretched in the direction of the crimped synthetic yarns therein there is bonded to one surface thereof a layer of a foamed rubbery material such as latex.
The textile fabric may consist of a woven, knit, or warp knit material which is fashioned entirely or only in part of wholly synthetic crimped yarns. Suitable stretch or elastic yarns are wholly synthetic filaments which have been crimped by being highly twisted, heat set and detwisted, or they may be crimped with the aid of interengaging rollers or by introduction into a stuffing chamber. It is also possible to impart a crimp to the yarn by drawing the same over an edge.
As indicated, the yarns of the fabric of the present invention are wholly synthetic, preferably polyamides such as polyhexamethylenadipamide (nylon) or polymerizates of epsilon-caprolactam or ll-aminoundecanoic acid. They may also consist of other wholly synthetic materials such as polyvinyls or polyesters, for example polyacrylonitrile or polyethyleneglycolterephthalate.
While the textile fabric layer of the composite elastic material of the present invention is preferably formed with only crimped synthetic yarns for reasons which will be apparent hereinafter, it is also within the scope of the present invention to employ a textile fabric which contains in addition to the crimped synthetic yarns some natural or synthetic inelastic yarns, for example cotton or wool, or yarns of viscose, cupramonium rayon or acetate rayon, preferably as a minor portion only of the fabric.
Suitable rubbery materials which may be employed are foamed latex, foamed materials of the reaction products of polyesters and polyisocyanates, or foamed .materials of polyvinylchloride dispersions. These materials are preferably poured in liquid form onto the textile surface, smoothed or leveled to the desired thickness, solidified and cured. Pouring and curing of the rubbery material on the textile fabric assures a good bond between materials. However, in some instances it may prove desirable to simply bond an already formed foamed latex sheet, for example, to the fabric. Suitable adhesives or bonding agents include rubber solutions, latex glue, and elastomerresin combinations.
By reason of the fact that the textile fabric component of the composite material of the present invention contains crimped synthetic yarns the fabric is stretchable in the direction of the crimped yarns regardless of whether the fabric be woven, knit or warp knit. It is of course also apparent that in the composite material of the present invention stretchability in all directions is desirable, and accordingly it is preferable that the textile portion of the material will be fashioned completely of crimped synthetic yarns.
Since the primary object of the present invention is to provide a composite fabric the textile portion of which will not give the impression of excess fabric or pucker upon repeated compression of the foamed rubbery material layer bonded thereto or by reason of contraction of any underlying independent layerof foamed material, the textile layer must be capable of substantial contraction.
This ability of the surface textile fabric to contract and thus take up any slack in itsel-fis imparted to the composite product of the present invention through stretching the yarns of the fabric by tensioning the fabric prior t'o and during application ofthe foamed rubbery material thereto. More specifically, the formed textile fabric is tensioned both longitudinally and transversely on a table an amount at least sufiicient to remove all surface irregularities and-creases which appear in the normally r'elaxed fabrici This tensioning, regardless of the structure" of the fabric, stretches the crimped yarns of which it is made. With the yarns thus stretched and'the fabric extended, there is applied to the textile fabric a homogenized-mass of viscous foam which is smoothed to the desiredthickness, allowed't'o harden, and with tension still applied to thev-fabric the rubbery mass is vulcanized at elevated temperatures or otherwise cured. Alternatively, an already formed and-cured sheet of foamed material of the desired thickness may be applied by means of an adhesive to the tensioned fabric. Regardless of the manner in'whic'h the foamed rubbery. material-is applied to the fabric, the cured rubbery mass is in its normally relaxedstate. That is to say, it is not underany tension or stretched as are the yarns which make up the surface textile fabric. Following curing of the foamed material, the tension previously applied to the textile portion of the composite material is relaxed. The elastic yarns remain in a stretched condition by reason of their bonding to the rubbery underlayer.
As" pointed out above preliminary tensioning is to a degree at least' sufficient to remove all creases and surface irregularities from therelaxed fabric, and is preferably to a degree substantially equal to the reduction in linear dimension of thefoamed material which will inevitably result from repeated compression thereof. The latter is the optimum degree of stretch imparted to the yarns of the fabric.
' The following non-limiting examples illustrate several composite elastic materials in accordance with the present inventionland several methods by which they may beprepared.
A mixedweave textile fabric containing 23.5 cotton threads of English yarrr number 20, per centimeter in the warp and 26.5 2-ply, 150 denier high-1y crimped elastic nylon yarns in the weft was employed as the surface textile. A latex foam mixture was prepared, which conmined the following constituents:
The various materials were added in an aqueous dispersion and air beaten into the mixture until the foam reached a'density of about 250 gr. per liter. There was then added 20-40 cc. of a ammonium chloride solution per kilogram of the mixture as a coagulant. The mixture was then homogenized and allowed to stand until, with increased coagulation, a viscous foam of the necessary solidity was formed. In this condition it was poured to a thickness of about.3 mm. onto the aforementioned mixed weave fabric, which was maintained under longitudinal and transverse tension .on a table. The latex foam was allowed to harden, and with the fabric still under. tension the. rubber was vulcanized by wet steam at 105- 110 .C. for 25 minutes. A subsequent wetting and drying inhot aircompleted preparation of the composite material, .after which tension on the fabric was relaxed.
Example II To Wa s. reta ners e -r aming 23-5 as! 26.5 2-ply highly elastic crimped denier nylon yarns per centimeter in the warp and weft respectively, which was tensioned in warp and weft directions, there was applied a layer of a thickness of 23 mm. of a foam obtained by pouring and levelling off the reaction product of the polyester ofadipic acid and diethyleneglycol with toluylene-diisocyanate andwater.
Example III A composite elastic material was prepared by first stretching lengthwise and widthwise on a plane surface a textile fabric consisting of a knitted fabric which had been produced'froma 2-ply highly elastic crimped nylon- 40-denier yarn on a warp knitting-machine with a fine-. ness of- 22 needles per inch, and then applying a. layer; of a thickness of 2-3 mm. of a foamed-polyvinylchloride dispersion.
The composite materials produced in the aforementioned examples were highly stretchable-in the directionof the crimped yarns of the respectivefabrics, and also sufiiciently contractible to compensate for ultimate reduction in dimensionof the foamed rubbery material.
In the. accompanying-drawing there is shown in enlarged. cross-section a-composite elastic material product of the-present invention. Thefabric-layer 1 isa woven material consistingof stretchable, crimped synthetic warp yarns Z-and weft yarns 3; Afoarned rubbery material 4, which is subject to reduction in dimensions upon repeatecl compression thereof, is bondedto the under side of .the..fabric 1. Warp and weft yarns 2 and 3; respectively, are. in a sligh-tly stretched condition in the cornposite material; thus enabling the fabric to contract andcompensatefor. subsequent reduction. in the dimensions of the rubbery material;
What is claimedisz 1. A stretchable composite upholstery material consisting essentially of-a stretchable fabric portion fashioned: atleastin part ofcrimped wholly synthetic yarns, said fabric portion being in a stretched condition-with the yarns-1thereofunder tension suflicient to'remove substantially all ofthe surface creases and irregularities normally apparent in said fabric when thesame is in relaxed,- unstretched-condition, and a layer of a foamed rubbery material, :which is subject to reduction in dimensions uponre-peated compression thereof, bonded to said -fabric portion, the tension in-the said yarns rendering'said fabric portion contractible to'thereby compensate for reduction inthedime'nsions of the foamed rubbery-material upon repeated compression thereof without substantial changein theuniform surface appearance of said fabric portion.
2. A stretchablecomposite upholstery material as set forth. inclaimtl wherein the crimpedwholly-synthetic yarn isselectedfrom the group consisting of polyacrylonitriles,. polyethyleneglycolterephthalate, polyhexameth ylenea'dipamides, polymerizates of epsilon-caprolactam and polymerizates of ll-arninoundecanoic acid.
3..A-.stretchable composite-upholstery material as set forth in claim .1 wherein the foamed rubbery material is selectedfrom the group consisting of latex, polyvinylchloride dispersions, andreaction products of polyesters and polyisocyanates.
4.'A stretchable compositeupholstery material consisting essentially of, a stretchable woven fabric portion fashioned of crimped wholly. synthetic yarns in the warp and weft, saidfabric portionbeingin a partly stretched condition with/the yarnsthereof under tension suflicient toremove substantially all of thesurface creases and irregularitiesnormally apparentin said fabric whenthe same is inrelaxed, unstretched condition, and a layer of afoamed rubbery material, which is subject to reduction in dimensionsupon repeated compression thereof, bonded to said partly stretched fabric portion, the tension in said r s assess sai .tabfi .rs i wo t a fib e. b
warp and weft directions to thereby compensate for reduction in the dimensions of the foamed rubbery material upon repeated compression thereof without substantial change in the uniform surface appearance of said fabric portion.
5. The stretchable composite upholstery material as set forth in claim 4 wherein the synthetic yarn is crimped nylon and the foamed rubbery material is foamed latex.
References Cited in the file of this patent UNITED STATES PATENTS Doell Jan. 15, 1946 Foster Oct. 12, 1948 Alderfer Aug. 18, 1953 Laros Feb. 9, 1954 Scholl Apr. 2, 1957