US 3142109 A
Description (OCR text may contain errors)
y 1964 R. G. STOLL EI'AL 3,142,109
FABRICS Filed Nov. 27. 1959 fl T United States Patent 3,142,109 FABRICS Reiner G. Stoll and Roland A. 'Fr'ate, Charlotte, -N.C., assignors to Celanese Corporation of America, New York, N.'Y.,' a corporation of Delaware Filed NOVw 27, -1959,-Ser. No.l855,'797 17 Cla'ims. -(Cl. 28-75) This invention relates to textile fabrics, and in particular to scrim fabrics and 'to methods'of producing the same.
Scrim fabrics are generally characterized by an open or wide meshstructure. Itisfor thisreason thatsuchfabrics very frequently are structurally unstable, i=e., the crossing' yarns can shift relative -toone another, thereby rendering the mesh arrangement uneven-and lessening the utility of such fabrics.
It 'is an object of the present invention to provide ,a scrim fabric which is freeof these heretofore-encountered disadvantages and is both structurally anddimensionally stable and sufficiently strong towithstand stressesin any direction in the plane of the fabric.
Another object ofthe present-invention is the provision of scrim fabrics in which crossing yarn stretches are bonded to one another at the; points of intersect -ion'thereof without any externally applied adhesive.
Still another object of the present invention isthe ,provision of scrim fabricsasaforesaid in which' some of the yarn is-composed of a syntheticthermoplastic fiber material capable of being plasticized by a plasticizer, while the remainderofthe-yarn-is-composed of amaterial inert .to or not subst-antially'aliected-bythe plast-i'cizer, the adhesion between these yarns at their points of intersection being effectedrby a rehardeningof the thermoplastic yarns after being plasticized andplaced in contact with theinert yarns.
A related object of the present invention, therefore,-is
"the provisionofsuch fabrics in which the plasticizer for the thermoplastic yarn is initially carried by the yarn which is inert to the plasticizer.
A further object of the present inventionis theprovision of a method of producing scrim fabrics:as aforesaid which comprises interweaving-yarns made of a synthetic thermoplastic fiber material -with-other "yarns which carry a plasticizer forthe thermoplastic-material.
Yet a further object of the present invention isthe provision of a method of producing scrim fabrics which comprises the bondingof yarns'toeach other at their crossover or intersection points -withoutany external application of an adhesive-or bonding material as-such. To this end, the fabric is composed partly of yarns of,a-thermoplastic;plasticizableirnaterial and partly of ya'rns of a different materialwhich is" inert toland thus adapted to' act as a carrier for a plasticizerfor the thermoplastic material. The bond thus is produced by the indirect plasticization of the thermoplastic-material and the subsequent hardening thereof. The bond may' becompleted by a 'hea'ting operation.
The thermoplastic'yarns maybe composed in whole or in part of plasticizable fibers, representative examples of which includepolyamides such as'nylon, polyestersis'uch as polyethylene vterephthalate, [acrylonitrile polymers" and copolymers, and olefin and olefinic esterp'olymersand copolymers such as polyethylene, polypropylene, polyvinyl 3,142,109 Patented July 28, 1964 chloride, poly vinyl acetate, and the like. Especially good results are achieved with organic acid "esters of cellulose such as celluloseacetate, cellulose :propionate, cellulose butyrate, cellulose. acetate -formate,- cellulose acetate jpropionate, cellulose acetate butyrate, and the like. 'Of these; cellulose acetate 1 is (preferred.
The other yarns employed in=tl;1e fabric may-comprise fibrous materials similar to those set forth above with the proviso that 'these materials 'must be substantially inert to or unaifected byplasticizersifor-ther thermoplastic :yarns.
'In accordance with-one aspectof the presentinvention, these'inert-yarns may comprise cellulose, e g. cotton .or
rayon,preferably high tenacityrayon having a tenacity in excess of about 5.0;grams-per denier, such as-i-s obtained by saponification of cellulose acetate. In;any given fabric, therefore, the :yarns carrying the plasticizer for the thermoplastic yarns will have adifferent composition-than the-latter-'so=- th;atthe pl-asticizer will selectively act ononly these yarns and cause'them to adheretto theinert carrier yarns at-the crossover-points.
The plasticizer employed in accordance with'tthe present'invention may be of any suitable acomposition and may-or-maynot' be .volatile. For example,:if the 'thermoplastic fiber yarn-isicellulose acetate and theother yarn cellulose, i.e.,\cotton or high tenacityrayon, the bonding mayibe best-effected by-means ofplasticizers such-as high boiling organic esters of carboxylic acids such as alkyl or -aryl esters of citric acid, v:adipic acid, --maleic acid and ,phthalic acid, organic esters of inorganicacids. such as-tri- .butyl phosphate and tricresyl phosphate, .alkoxy alkyl esters of inorganic tpolybasic .-acids or organic ,polybasic acids,ihigh boiling .ethers such'asbutyl etheriof ethylene may be followed by a wiping operation to remove excess liquid so as topreventtdripping. Thetamount-oflplasticizer carried by the'inert vyarns will depend upon the spacing -and-relative-weight of the thermoplastic yarns as well as .upon the" activity of the particular plasticizer and its concentration. The-,plasticizer'may'also comprise a solvent for. the thermoplastic material -:which, under the prevailing circumstances, is incapable of effecting any appreciable dissolution, e.g. it is applied in very small gproportionrelative to the thermoplastic materialor it is'em- .ployed-diluted with non-solvents. .In the reventsuch 1a solvent isemployed preferably. itsis .volatile,..such as..ace
tone, methylene chloride or the like for cellulose esters,
since :upon evaporation the bond will be of increased strength.
The thermoplastic andinert-yarns may be combined with one another into "the desired fabric form by any suitable intermeshing-Qper-ation such as regular-or-leno weaving, knitting, .e.g.,-war-.p knitting, or the like. .cordance with one aspect 0f the ,present --invention, 'the inert,yarns-.are taken-from .a .warp. beam and passed over In aca smallkiss roll arranged invadvance of the drop wires of a'loom, whereby theplasticizer is applied to these, yarns by surface contact. An electric heating device is a1- 3 ranged on the loom adjacent the exit path of movement of the fabric so as to heat the intersecting yarns and to complete the bonding initiated by the plasticization of the filling or weft yarns by the plasticizer carried by the warp yarns.
The foregoing and other objects, characteristics and advantages of the present invention will be more fully understood from the following detailed description thereof when read in conjunction with the accompanying drawing, in which:
FIG. 1 is a diagrammatic illustration of an arrangement for forming a bonded scrim fabric according to the present invention; and
FIG. 2 is a diagrammatic plan view of a scrim fabric formed by the device shown in FIG. 1.
Referring first to FIG. 2, it will be seen that the scrim fabric according to the present invention comprises a plurality of warp yarns 11 interwoven with weft or filling yarns 12. The warp yarns 11 are desirably cotton or rayon, preferably high tenacity rayon having a tenacity in excess of about 5.0 grams per denier. The yarns 12, on the other hand, are composed of a synthetic thermoplastic fiber material, cellulose acetate being preferred.
The yarns 11 and 12 are bonded to one another at their crossover or intersection points 13 by virtue of the fact that the warp yarns 11 prior to the weaving operation carried a plasticizer for the yarns 12 which, consequently, were plasticized upon coming into contact with the warp yarns 11 so as to adhere to the latter.
As shown in FIG. 1, the warp yarns 11 may be unwound from a warp beam 14 and passed over a small kiss roll 15 partially immersed in a quantity of any suitable plasticizer 16. 'The portions of the yarns 11 at the location 11a thus are coated or impregnated with the,
plasticizer 16 which, of course, has no softening effect on the material of which the yarns 11 are made. In this condition, the warp yarns 11 are fed into a loom or similar fabric-forming device 17 in which they are interwoven by conventional means (not shown) with the filling yarns 12. The latter, as hereinbefore stated, become plasticized upon coming into contact with the warp yarns 11 due to the migration of the plasticizer and thus tend to adhere to the warp yarns. After the fabric has been formed, it is subjected to the action of an electric heating device 18 mounted on the loom 17, which effects a completion of the bonds between the yarns 11 and 12. The completed fabric 10 is then removed from the loom and wound up on any suitable take-up roll 19 on which it may be stored and shipped to the ultimate consumer.
It will be understood, of course, that the arrangement may be reversed, with warp yarns being made of thermoplastic fiber materials while the filling yarns are made of materials inert to the plasticizers for the warp yarns.
Moreover, the yarns which are to be plasticized need not be made completely of a thermoplastic fiber material, the only requirement being that they contain some plasticizable material. The other yarns, i.e., those carrying the plasticizer, must, however, be composed solely of materials not substantially affected by the plasticizer.
Scrim fabrics produced in accordance with the present invention are suited for use as backings or embedded reinforcements for non-Wovens, as sanitary napkin coverings, surgical bandages and other medical uses, and the like.-
The invention is further illustrated in the following example.
Example A fabric having 18 ends and 18 picks per inch is woven from 60/2.5/ 80 high tenacity rayon warp and 100/2/ 26 cellulose acetate filling. On the way to the loom the warps pick up 50% of. their weight of a 30% aqueous 7 solution of diacetin. Following weaving, the scrim fabric is heated over a radiant electric heater to 220 F. and is a then taken up on a roll.
It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.
Having described our invention what we desire to secure by Letters Patent is:
1. A textile fabric, comprising intersecting and intermeshed first and second yarns which are separate along most of their lengths, said first yarns at least partly comprising a thermoplastic fiber material capable of being plasticized by a plasticizer, all the material making up said second yarns being substantially inert to said plasticizer, said first and second yarns being bonded to one another at their crossover points by the action of said plasticizer which is substantially non-adhesive and is initially carried by said second yarns.
2. A textile fabric according to claim 1, wherein said first yarns are composed entirely of said thermoplastic fiber material.-
' grams per denier.
4. A textile fabric according to claim 1, said thermoplastic fiber material comprising cellulose acetate.
5. A textile fabric according to claim 1, said thermoplastic fiber material comprising nylon.
6. A scrim fabric, comprising intersecting and intermeshed thermoplastic fiber yarns and other yarns which are separate along most of their lengths and are bonded to one another at their crossover points by the action of a plasticizer for said thermoplastic fiber yarns which is substantially non-adhesive and is initially carried by said other yarns, all the material making up said other yarns being substantially inert to said plasticizer.
7. A scrim fabric according to claim 6, said thermoplastic fiber yarns and said other yarns intermeshing with one another by weaving.
8. A scrim fabric according to claim 6, said thermoplastic fiber yarns and said other yarns intermeshing with one another by knitting.
9. A scrim fabric according to claim 6, wherein said thermoplastic fiber yarns comprise an organic acid ester of cellulose.
10. A scrim fabric according to claim 6, wherein said thermoplastic fiber yarns comprise cellulose acetate.
, 11. A scrim fabric according to claim 6, wherein said other yarns comprise cellulose.
12. A scrim fabric according to claim 11, wherein said other yarns comprise rayon having a tenacity of at least 5.0 grams per denier.
13. The method of forming a textile fabric, comprising the steps of intermeshing first yarns at least in part comprising a thermoplastic fiber material capable of being plasticized by a plasticizer with second yarns, all the material making up said second yarns being substantially inert tolsaid plasticizer, and applying said plasticizer to said second yarns prior to the intermeshing thereof with said first yarns, whereby following intermeshing said first and second yarns are bonded to one another at their crossover points by the action of said plasticizer on said first yarns.
14. The method of claim 13, further including the step of heating said first and second yarns subsequent to the intermeshing thereof for improving the bond therebetween.
ISJThe method of claim 13, wherein said intermeshing step comprises weaving said first and second yarns on a loom.
16. The method of claim 13, wherein said intermeshing step comprises knitting said first and second yarns 17. The method of claim 13, wherein the thermoplastic fiber material of which said first yarns are made comprises cellulose acetate.
(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Koch July 4, 1922 Fether May 25, 1937 Brew Jan. 19, 1943 Whitehead Feb. 22, 1944 Bihaly Feb. 1, 1949 Feild et a1. Jan. 2, 1951 Bihaly Dec. 16, 1953 6 Bihaly Aug. 7, 1956 Ball Nov. 27, 1956 Conner Oct. 29, 1957 Harwood Aug. 25, 1959 FOREIGN PATENTS Canada Dec. 30, 1958 Great Britain Sept. 7, 1943 Great Britain Mar. 4, 1959