US2874729A - Durable open-mesh fabric - Google Patents

Description

Feb. 24,'*1959 ALL. BALL DURABLE ()PEN MEsl-i FABRIC 2 Sheets-Sheet 1 Filed Sept. 20. 1955 .lmilln.

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Feb. 24, 1959 A. L. BALL DURABLE OPENMESH FABRIC Filed Sept. 20. 1955 2 Sheets-Sheet 2 INVENTOR. 0/5672 L Bali United s teS Pa 01ice 2,874,729 Patented Feb. 24, 1959 2,874,729 DURABLE OPEN-MESH FABRIC Albert L. Ball, Worcester, Mass., assignor to Bay State Abrasive Products Company, Westboro, Mass., a corporation of Massachusetts Application September 20, 1955, Serial No. 535,341 10 Claims. (Cl. 139-383) This application relates to fabrics and is particularly concerned with open-mesh fabrics that are durable and resistant to slippage,

Open-mesh fabrics, that is fabrics in which both the warp and filling yarns are relatively widely spaced, are desired and used for many purposes. A serious disadvantage of such fabrics, however, is their lack of durability which results from the tendency of the yarns thereof to slip or shift. This tendency is particularly troublesome where smooth or slippery, synthetic fiber yarns are employed. Indeed, to' obtain an open-mesh fabric which is at all durable it has hitherto been necessary to use the leno or gauze weave, in which a double warp twisted around the filling yarns is employed, instead of the simpler and less expensive plain or twill weaves.

Broadly, the object of the present invention is to provide an open-mesh fabric which is strong and durable.

' More specifically, it is an object of the invention to provide an open-mesh fabric, the yarns of which are secured against slipping with the consequent production of irregularities in the fabric.

Another object of the invention is to provide a strong, durable, open-mesh fabric the warp and filling yarns of which are fastened together by an adhesive at their points of interlacing or crossing.

7 Other objects and advantages of the present invention will be apparentfrom the following description taken in conjunction with the accompanying drawings in which:

Figure l is a fragmentary, side elevation of a conventionalized loom, carrying means, shown partly in section, for producing an open-mesh fabric according to the present invention;

Figure 2 is a fragmentary, top plan view of the loom shown in Figure 1 with portions of the yarns and fabric omitted to better show the mechanical details;

, Figure 3 is a fragmentary, enlarged view of an openmesh fabric which has been produced in accordance with the present invention;

Figure 4 is a section on line 4-4 of the fabric shown in Figure 3; and v Figures 5 and 6 are fragmentary, enlarged views illustrating a couple of the many other open-mesh fabrics which are comprehended within the present invention.

A novel process by which open-mesh fabrics according to the invention may be produced is the subject of copending application Serial No. 365,641, filed July 2, 1953, now Patent Number 2,771,659, of which the present application is in part a continuation. In such process the warp and filling yarns of an open-mesh fabric are attached or joined at their points of interlacing or crossing by an adhesive material while the fabric is still on the loom and while the warp yarns of the fabric are still under the normal tension of the loom. Thus the yarns are not given an opportunity to slip and the uniformity of weave of the fabric is preserved. At the same time, if a flexible adhesive is employed, the fabric remains flexible and easily handled. As a result of the widevariations in physical. and chemical properties of adhesives which may be used in carrying out the process, the characteristics of the fabric may be greatly varied to produce novel and useful effects and to render the fab ric. more suitable for certain purposes.

One form which apparatus to carry out the novel process of said copending application may take is illustrated, somewhat diagrammatically, in Figures 1 and 2 of the drawings. Inthese figures there is shown, and designated generally by the reference character 11, the front portion of a loom upon which such apparatus is mounted. The loom 11 includes a pair of side frames each of which comprises a front pedestal 13 and a pair of longitudinal girders or struts 15 and 17. On a portion of the loom 11 the warp 19 and the finished fabric 23 are shown in place.

According to one method of operation of a loom the odd yarns 20 of the warp 19 and the even yarns 21 thereof pass, respectively, through separate heddles (not shown) and are alternately raised and lowered by the heddles to separate them and thereby to form the shed shown in Figure l. The shuttle (not shown) is projected back and forth transversely of the loom 11 through the shed laying down the filling yarn from a bobbin carried thereby. The positions of the warp yarns 20 and 21 are changed by the heddles between each passage of the shuttle. Thus each successive pick or filling yarn in the fabric passes under and over, respectively, the warp yarns that the next preceding pick passed over and under. The result is a plain weave fabric or cloth 23.

The fabric 23 passes over the transversely disposed breast beam 25 of the loom and around the guide roll 27 and is drawn taut by the take-up roller 29 which, if desired, may be covered with abrasive paper or be otherwise provided with a roughened surface for posi tively gripping the fabric and putting tension on the warp. From the take-up roller 29 the fabric passes around the guide roll 31 and is wound upon the cloth beam or roller 33. The take-up roller 29 and cloth roller 33 are driven by mechanism (not shown) arranged to advance the woven cloth 23 and attached warp 19 evenly and continuously through the loom 11 during the weaving process.

Extending upwardly on each side of the loom 11 is a sword 37. At their lower ends the swords are mounted on a transverse rocker shaft 39 and are caused to oscillate thereon by a pivotally connected crank 41 which is usually operatively connected to the picker mechanism (not'shown). At their upper ends the swords 37 carry the transversely extending lay 43 and the reed 45. The reed 45 comprises an array of parallel wires 47 extending between the lay 43 and the bar 49 that is parallel and separated by the latter.

parallel with and above the lay and is carried thereby. Thewarp yarns 20 and 21 pass through the openings in the reed between the wires 47 and are maintained The reed, moving with the oscillating swords 37, is given a forward and backward motion in the loom; In its rearward position it leaves room in the shed for the shuttle to pass through the shed on the lay 43 in front of the reed and lay down a filling yarn 22. After each passage of the shuttle the reed 45 moves to its forward position and battens the pick or filling yarn 22 just laid down, moving it into place in the fell 24 of the fabric 23. When a closely woven cloth or fabric, that is one having a high cloth count or thread count, is being woven the action of the reed in battening the filling yarns is to give a firm, compact construction to the fabric. Where, however, as in the present invention, the fabric woven is an open weave one, the reed serves merely to V straighten out and evenly space the successive picks as Uniformity of beam (not shown) at the rear of the loom 11 through the;

heddles (not shown) and the reed 45 into the fabric 23 and that they are under tension throughout the weaving process. The warp beam is normally equipped with a device for imparting resistance to rotationthereof and, as previously described, the fabric 23 after passing over the breast beam 25 is gripped by the take-up roller 29 and is thus held firmly. The mechanism (not shown) for causing operation of the take-up roller and the cloth beam or roller 33 is positively driven by the loom apparatus to provide an even movement of the warp 19 through the loom as the cloth is woven, thereby permitting the weaving of an open mesh fabric with uniform mesh openings. The take-up mechanism for the cloth or fabric is, of course, accompanied by a suitable let-off mechanism for the warp beam.

The invention of the present application is concerned with open-mesh fabrics of various types of weave and of various fibers. Thus, even though open-mesh fabrics formed with a gauze or leno weave are somewhat durable, they may be rendered much more resistant to yarn slippage by treatment according to the novel process of the above-mentioned copending case. On the other hand, ordinary open-mesh fabrics having a plain weave or a twill Weave are lacking in durability since the yarns thereof are easily displaced by ordinary handling such as, for example, rewinding from the cloth beam. Open-mesh fabrics of this type formed from yarns of continuous, relatively smooth fibers such as glass fibers and synthetic organic fibers are particularly susceptible to such damage. Such fabrics may, however, be given greatly increased durability and strength and be made useful by treatment according to the process of the above-mentioned application. Previous open-mesh fabrics having a satin or sateen weave have been of only slight usefulness since the long floats characteristic of such weaves have made the fabrics extremely sleazy. Treatment of such fabrics according to the mentioned novel process will considerably increase their durability though they will still be comparatively flimsy.

As indicated above, the present invention is particularly concerned with durable open-mesh fabrics woven from yarns of relatively smooth, continuous filament fibers such as rayon, nylon, other synthetic organic fibers, and glass fibers since open-mesh fabrics of such yarns are especially subject to slipping and displacement of the yarns with consequent distortion of the fabric. Fabrics woven from yarns comprising only a single filament as well as from multi-filament yarns are included although it will be recognized that the latter tend to be more flexible than the former. The invention also comprehends, however, durable, open-mesh fabrics woven in whole or in part from organic or inorganic yarns of other types such, for example, as spun yarns of cotton, linen, rayon, wool, glass and asbestos. Yarns of various sizes may of course be used in weaving any of the above-mentioned types of fabrics.

Apparatus suitable for carrying out the novel process covered by the copending application referred to above is shown diagrammatically in Figures 1 and 2 mounted on the upper longitudinal girder 15 of the loom 11 between the reed 45 and the breast beam 25. It comprises, in order from left to right as viewed in Figure 1, adhesive applying apparatus including a tank 53, a ga jet or nozzle 57, and drying or setting means 63 for the adhesive.

The adhesive tank or vat 53 extends crosswise of the loom 11. Rotatably supported in the tank 53 is a horizontal, adhesive-applying roller 55. The adhesive 56 in the tank is maintained at such a level as to permit the roller 55 to pick up adhesive as it rotates and carry the adhesive to the fabric 23. The latter frictionally engages the upper surface of the roller 55 and in its movement through the loom causes the roller to revolve. The yarns of the :fabric are thus coated with adhesive as they pass over the roller.

The gas jet or nozzle 57 comprises a body or tube that extends transversely of the loom and has, projecting upwardly therefrom, an extension 59 provided with an elongated orifice 60 through which gas admitted to the body through the flexible connection 61 may be expelled. The orifice 60 extends the full width of the fabric 23 and is preferably provided with suitable and convenient means (not shown) for adjusting its width. The stream of gas issuing at high velocity from the orifice 60 serves to break films of adhesive that blind, i. e. extend across and close, the mesh openings of the fabric, thus opening the meshes and preventing the fabric from appearing faulty or irregular. When using thick, viscous adhesives a higher gas velocity will be required to break the adhesive films than when thin or less viscous adhesives are used. With constant inlet pressure to the jet 57 the velocity of the gas stream issuing from the orifice 60 as well as its thickness depends upon the adjustment of the orifice width. It has been found that when the gas pressure in the hose or pipe 61 is about 20 p. s. i. an orifice width of from about 0.010 in. to about 0.030 in. produces satisfactory results. The velocity of the gas stream should not be greater than required to unblind the mesh openings since a stream with excessive velocity may displace or render irregular the film of adhesive on the yarns. Preferably, the gas employed in the nozzle or jet 57 is air although, where circumstances require, steam or other gases may be used.

After any mesh openings of the open-mesh fabric 23 that are closed by adhesive films are unblinded by the gas stream from the nozzle 57, the adhesive is dried or set by conversion to the solid state on the yarns of the fabric. This, in many cases, may be conveniently done by the application of heat. In the drawings the reference character 63 has been applied to a radiant heater which is supported on the girders 15 by legs 65. The radiant heater 63 may be of any of the well known types, the heat being emitted by a series of battery of infra-red lamps or other heating elements 66 and directed upon the coated fabric by a reflector 67. If required, a similar heater may be mounted on the loom 11 under the fabric 23 so that heat is applied to both sides of the fabric. It will be obvious that, if needed or found desirable, other devices may be used for setting or assisting in the setting of the adhesive applied to the fabric. Such devices may be used in conjunction with heating means or in place thereof. Examples of such devices are blowers, which may pass heated air over or through the fabric, and sprays, which may apply a precipitant or a hardening or conditioning agent to the surface of the adhesive.

In the following example there is described the manufacture of a durable open-mesh fabric according to the present invention.

Example I A loom set up to produce a 24 x 24 mesh fabric using 300 denier rayon warp and filling yarns, is provided with apparatus of the type described above. The adhesive tank is supplied with a latex solution or dispersion formed by mixing about 3000 cc. of water with about 30,000 cc. of white neoprene latex, such as the grade sold by General Latex and Chemical Co. under the designation Z16. The latex solution should be thin enough to thoroughly coat the yarns or the fabric even though it is applied by a roller to only one side of the fabric. At the same time it should be thick enough not to run or drip off so as to make the coating on the,

yarns uneven. A solution having a viscosity of about centipoises at 25 C. has been found quite suitable for use and results in an increase in fabric weight after drying of the adhesive coating of about 0.0035 lb./ft. After passing over the adhesive applying roll and receiving a coating of latex the fabric on the loom passes over the orifice-of the air nozzle 59. A high velocity stream of air emerging therefrom may be employed to unblind any mesh openings that have'been closed by a film of latex. There is also, of course, some drying of the latex solution by the action of the air, depending upon the volume and temperature thereof. This drying effect may be increased by using heated air. The latex-coated fabric then passes under an infra-red heater, the heat from which drives off the water of the latex dispersion and causes the neoprene to set to a continuous film around the yarns. The resulting fabric with neophene-coated yarns is wound up, under tension, on the cloth roller of the loom from which it is periodically removed in accordance with general practice.

It will be understood that multiple filament or fiber yarns in fabrics subjected tothe method described above, in contrast to yarns comprising only a single filament, will, to some extent at least, be impregnated by the applied adhesive as well as coated thereby. The extent of the impregnation of such yarns will depend largely upon the degree of twist of the yarns. Tightly twisted yarns will be less absorbent than loosely or slack twisted yarns. The latter will in most cases be completely impregnated with the adhesive. With some yarns such impregnation may be particularly desirable as the strength of the yarns will thereby be increased. Since, as described in the immediately preceding parargraph, the adhesive is applied to the yarns of the fabric while the warp yarns are under tension, it is obvious that upon release of such tension the adhesive coatings surrounding and impregnating the warp yarns will be under slight compression. In the application of adhesive to a particular fabric it will of course be necessary to use enough adhesive to leave a surface coating adequate to cement the yarns of the fabric together at their points of intersection. Consequently allowance must be made for the absorbency of the yarns employed. Heavier or lighter application, respectively, may be obtained by increasing or decreasing the concentration of the adhesive dispersion or solution used. In general, when using peoprene latex, an application which results in an increase in fabric weight after drying or setting of from about 0.0015 to about'0.0040 lb./f t. is sufficient for the purpose of the invention. Heavier coatingsare, however, unobjectionable, providing the size of the fabric mesh openings is not too greatly'reduced. Such coatings may be obtained by applying greater amounts of material in one coating application or by making successive applications of the coating material. With other adhesives that differ in specific gravity from neoprene, equivalent coatings will require the application of greater or lesser amounts of solution or dispersion.

Figures 3 and 4 are enlarged, diagrammatic views of an open-mesh, plain weave fabric the warp and filling yarns 71 and 72, respectively, of which are provided with a flexible coating such as is obtained by the procedure set out in the preceding example. Not only are the yarns coated with an adhesive film 74 between their points of interlacing but also, as best seen from Figure 4, the film of adhesive extends between and around the yarns. at such points thereby fastening or cementing the yarns together and making the fabric much stronger and more ,durable than an ordinary open-mesh, plain weavefabric. V

.Figures 5 and 6'illustrate diagrammatically two of the many other types of open-mesh, woven fabrics with which the present invention may be employed. In Figure 5 there is shown anevenfltwo and two, twill weave in which each filling yarn, .77 interlaces two. warp yarns 76. Another 'type of open mesh, pla'in weave is shown Figure 6. Here a pair of small closely spaced warp yarns 80,-which together are about equal in width to the filling yarns 81 used, are picked as one, i. e. are handled as a single warn yarn. Such a fabric is, in general, like an ordinary plain weave fabric but because of the smaller 'warp yarns is somewhatflatter or smoother. As

previously mentioned, yarns of various sizes may be used invention. a

It is to be noted that the present invention is concerned, not with coated fabrics of the nature of oil cloth and the like to which the term is frequently applied, but with an open-mesh fabric or cloth in which the yarns are coated and cemented together at their intersections and in which the mesh openings are relatively large and are substantially .all unobstructed. Thus, the coated cloth or fabric retains essentially the desirable characteristics of the original uncoated fabric but is stronger and more durable and may, as pointed out hereinafter, have additional valuable properties.

For the purpose of the present invention, as abovementioned, an open-mesh coated fabric is one in which the mesh openings are relatively large and substantially all are clear and unobstructed. Although the size of the mesh openings may vary greatly, it is considered that to be an open-mesh fabric the mesh openings, which are substantially rectangular, should not measure less than about 0.02 in. along a side. The coated fabric resulting from the process described in Example 1 is typical. In this fabric the mesh openings are substantially square and measure 0.027 in. (average) on each side while the average distance from one mesh opening to the next (the diameter of the coated yarns) is only 0.015 in. The ratio of average mesh opening side to average intervening distance between mesh openings is, therefore, substantially 120.55.

For convenience in describing the character of openmesh, coated fabrics, this ratio A:B, in which A is the average length of the side of a mesh opening and B is the average distance between mesh openings (measured parallel to said side), will hereinafter be referred to as the mesh opening-yarn ratio of the fabric. It will be noted that in coated fabrics like those heretofore described herein the yarn of the above mentioned ratio includes the coating on the fabric yarns. Further, to be considered open-mesh for the purpose of the present invention this ratio A:B should not be less than 1:4 and A should be greater than the thickness, as viewed from the edge of the fabric, of the largest yarn used. On the other hand, the ratio may in some cases be quite large as coated, openmesh fabrics with ratios of about 1:0.05 have been made successfully. The feasible upper limit for the mesh opening-yarn ratio in any particular case is determined by the use'for which the coated fabric is intended. For fabrics having a specified cloth count the ratio can be increased only by decreasing the space between the mesh openings. This requires reduction in either the yarn size or the thickness of coatings on the yarn or both. Obviously, there is a point below which the coating is insufiicient to cause adherence of the yarns at their points of interlacing. Furthermore, although open-mesh fabrics coated in accordance with the present novel process are stronger than the same fabrics before coating, weaving difficulties as well as inferior strength in the resulting fabric may be expected from excessive reduction in yarn size.

Where a plurality of closely spaced, relatively parallel yarns are employed, as, for example, in the fabric illustrated in Figure 6, the yarns for various reasons are never absolutely parallel and in continuous contact. Thus, there will always be a number of minor openings which differ in size, but are all quite small in comparison with the planned, major, mesh openings. In coating open-mesh fabrics having such minor openings the latter are filled or closed by the coating material The mesh openings remaining in the coated fabric correspond to the major mesh openings only of the base fabric. Consequently,

for the purposes of the present invention such minor mesh openings may be disregarded and each group of relatively parallel, juxtaposed yarns may be considered as a single flattened yarn.

Within the scope of the present invention many openmesh, coated fabrics of varying types have been produced. Such-fabrics have involved plain and twill weaves as well as weaves utilizing multiple yarns, one exarnple of which is shown in Figure 6. The average mesh openingyarn ratios of these fabrics have ranged between about 1:005 and 1:35. It will be understood that ratios below about 1:1 are obtained by the use of multiple, juxtaposed yarns.

Other adhesive materials may, of course, be used instead of neoprene latex for coating open-mesh fabrics in accordance with the invention. Among the materials which may be so employed are other synthetic rubber latices such, for example, as those sold under the names Hycar" and Geon by B. F. Goodrich Company. The former products are dispersions of synthetic rubber-like materials of the butadiene copolymer type while the latter are dispersions of the modified vinyl chloride type. Natural rubber latex, solutions or emulsions of plastic materials such as polyvinyl butyrate resins, melamine resins, polyvinyl acetate, ethyl cellulose and the like, as well as solutions of casein, starch, natural gums, and glue may also be used. All of the materials mentioned are relatively flexible and are therefore intended for use where a flexible fabric is desired. If, however, an open-mesh fabric product which is less flexible or more rigid is desired other types of adhesive may be used which when hardened or dried are less flexible. Such adhesives are, of course, well known and any suitable one, such for example as a liquid phenolic resin may be used.

The adhesive coating on the yarns of an open-mesh fabric, in addition to rendering the fabric more durable and less subject to damage by slippage of the yarns, makes possible other novel and beneficial effects and uses. Thus, a colored fabric may be obtained by incorporating a dye in the adhesive solution or dispersion even though some or all' of the yarns or fibers of the fabric are diflicult to dye. In other cases the adhesive coating on the yarns may be dyed more easily than the underlying yarns and a subsequent dyeing operation may be used.

As indicated above, an outstanding feature of the process herein described is the fact that the coated, openmesh fabric is held under the original loom tension during the application of the coating adhesive and the drying thereof. Thus, not only is it possible to avoid the use of costly tentering machines, but also, since handling of the fabric between the weaving and application of adhesive is not required, the chances of yarn slippage and fabric spoilage during such handling are reduced to a minimum.

Coated, open-mesh fabrics according to the present invention may be obtained by methods other than the abovedescribed one, which involves the application to the fabric on the loom, or at least while it is still under the original loom tension, of an adhesive material which coats the fabric yarns and causes their adherence or attachment at their points of interlacing or intersection. A substantially identical product may be formed by a similar though somewhat different method. According to this modification, both the warp and filling yarns to be employed are coated separately with a suitable heat-softenable adhesive material which may, if desired, be selected from the adhesives listed above. An open-mesh fabric is woven from such coated yarns. While the fabric is still under the loom tension it is heated suificiently, by any suitable heating means, as to cause adherence or tacking of the yarns at the points of their intersection.

A similar product may also be formed by a process which resembles the alternative one above described, but does not involve the use of an adhesive coating for the yarns. Since a number of synthetic organic fibers, such for example, as saran, nylon, and Vinyon are themselves heat-softenable, it is possible when weaving open-mesh fabrics from yarns of such fibers to suitably heat the fabric while it is still on the loom, applying moderate pressure if necessary, and thereby cause the yarns of the fabric to become attached at their points of interlacing before any slipping or displacement of the yarns has occurred. It will be obvious that in carrying out this lastmentioned process the heating must be done carefully to avoid causing undesirable fiow of the yarns or coalescense of the filaments in the yarns.

Although in the foregoing specification there have been described certain apparatus and processes by means of which the novel products of the present invention can be manufactured, it will be understood that such apparatus and methods are merely exemplary and that such products may be produced by methods and apparatus varying from those described. For example, if desired the adhesive may be sprayed on'the yarns of the fabric by suit able apparatus instead of being applied by a roller. Since it is used with a loom, the design of any apparatus employed is subject to modification according to the loom construction. It will therefore be further understood that various details of the described processes may be changed or modified without departing from the spirit of the invention.

I claim:

1. A strong, durable, open-mesh, woven fabric the warp and filling yarns of which are adhesively attached at their points of interlacing by an adhesive which at least partially impregnates said yarns and which coats said yarns over their entire exposed surfaces, said fabric having a structure in which the mesh opening-yarn ratio (AB) is not less than 1:4 and A is greater than the thickness, as viewed from the edge of the fabric, of the largest yarn used therein and is not less than 0.02 in., the coating on said warp yarns being under slight compression, and the mesh openings of said fabric being substantially unobstructed, having shapes substantially as woven, and being free of distortion resulting from contact with said fabric subsequent to weaving and prior to the application of said adhesive.

2. An open-mesh coated fabric as set forth in claim 1 which comprises, at least in part, continuous filament yarns.

3. An open-mesh, coated fabric as set forth in claim 1 in which multiple warp yarns are used.

4. An open-mesh, coated fabric as set forth in claim 1 in which multiple yarns are used in forming both the warp and filling of said fabric.

5. An open-mesh, coated fabric as set forth in claim 1 in which said coating is colored.

6. An open-mesh, coated fabric as set forth in claim 1 in which said coating is formed of a synthetic plastic material.

7. A11 open-mesh, coated fabric as set forth in claim 1 in which said coating is flexible and formed of a material selected from the group consisting of natural and synthetic rubbers.

8. An open-mesh, coated fabric as set forth in claim 1 which comprises, at least in part, continuous filament yarns, and in which at least the warp of said fabric is formed of multiple yarns.

9. An open-mesh, coated fabric as set forth in claim 8 in which said coating is formed of a synthetic plastic material.

10. An open-mesh, coated fabric as set forth in claim 8 in which said coating is flexible and formed of a material selected from the group consisting of natural and synthetic rubbers.

References Cited in the file of this patent UNITED STATES PATENTS 2,058,476 Lovett Oct. 27, 1936 2,333,618 Strauss Nov. 2, 1943 2,360,245 McFarlane Oct. 10, 1944 2,514,603 Haney July 11, 1950 2,594,521 Tingley Apr. 29, 1952 2,601,770 Goldsmith July 1, 1952 2,696,847 Cotterill et a1. Dec. 14, 1954

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