IL22483A - Non-woven fabrics - Google Patents

Description

Patents Form No. 3 PATENTS AND DESIGNS ORDINANCE.

SPECIFICATION .

FON-WOVEN FABRICS Γ / WE , ΟΒΑΪΜ a corporation of tfca state of Belaware* of 522 Fi Av&aae, M York 10036, State of Kew York, United s ates of America. do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described aud ascertained in and by the following statement : - This invention relates to non- oven products, as well as to process of and apparatus for manufacturing such products.

Non-woven fabrics for use in the manufacture of gas and liquid filters, clothing and a great number of other products are known. Usually, such non-woven fabrics are composed of webs of stabple fibers carded and spun in conventional manner,, The staple fibers, if synthetic, are formed by cutting extruded synthetic continuous filaments into appropriate lengths.

As is well known, staple fiber non-wovens, by their very nature, are not possessed of any considerable inherent tensile strength in any direction and thus are ordinarily easily distorted and even destroyed unless specially reinforced. Merely by way of example, such reinforcement may entail the application of a suitable binder or bonding agent to the web of spun staple fibers with or without the concurrent application of heat and/or pressure, or the lamination of such webs to relatively stable woven fabric sheets either by adhesion or by needling or stitching. Nevertheless, it has been found that staple fiber non-wovens, even when so reinforced, do not have the desired degree of stability and durability, since they not only tend to lose fibers through migration but are also not adequately able to retain bulk, compressibility, resiliency, etc., even after only relatively short periods of use.

It has been proposed heretofore to avoid some of these drawbacks and disadvantages of staple fiber non-wovens by producing non-woven fabrics entirely from continuous synthetic filaments. According to one of such proposals, the filaments are entruded toward a flat, substantially horizontal, moving take-up surface from an extrusion jet or group of jets mounted to be reciprocally traversed across the direction of movement of the take-up surface, while one or more streams of compressed air are blown at the extruded bundle or bundles of filaments as they move toward the take-up surface. This causes the filaments to be whipped about an<T^nterlace¾ ' or mingled to a considerable extent in a random manner before they reach the take-up surface. The so agitated streams of filaments are thereby, when finally deposited on the take-up surface, formed into a coherent mat or web of predetermined width and height.

The resultant non-woven sheet material, being composed of continuous filaments, is not subject to fiber losses, as are staple fiber non-wovens. The filaments, however, are interlaced and deposited onto the take-up surface while still in a relatively plastic condition, and thus they become fused to one another at their points of intersection and contact. The physical characteristics of the continuous filament non-woven fabrics so formed are, therefore, essentially fixed and invariable. Stated in other words, such continuous filament non-wovens can be produced only by the filament manufacturer and cannot be changed subsequently by the user, i.e. the manufacturer of the finished products, if somewhat different physical characteristics of the fabric or sheet material are desired.

It is a principal object of the present invention to provide for the production of non-woven intermediate products adapted for use in the manufacture of a variety of textile and non-textile end products from synthetic continuous filaments in such a manner that the physical characteristics of such intermediate products can he selected and determined by the manufacturer of the end products.

Another object of the present invention is the production of non-woven products as aforesaid from coherent, intrinsically non-adherent continuous filament tow„ It is a more specific object of the present invention to provide for the formation of non-woven webs or bands from initially crimped continuous filament tow by subjecting the same to a crimp-deregistering treatment and to a filament spreading treatment prior to a finishing treatment and to a filament spreading treatment prior to a finishing treatment during which the desired intermediate and/or end products are formed.

A further object of the present invention is the provision of a variety of specialized processes of and apparatus for treating crimped, intrinsically non-adherent, synthetic continuous filament tow in such a manner as to enable a great number of substantially non-woven textile and non-textile end products to be manufactured therefrom.

In its general aspects the basic process of the present invention comprises subjecting the initially coherent multi-filament tow being fed along a predetermined path, to a differential gripping action between a plurality of points spaced from one another both longitudinally and transversely of the path, so that' certain laterally spaced sections of the tow are positively gripped relative to other laterally spaced sections of the tow, alternating with the said gripped sections, which are not gripped at all or are gripped at different relative points. In this manner there is produced, as a function of the differential positive gripping of the tow, a relative shifting of adjacent filaments longitudinally of the tow, whereby the crimps are moved out of registry with one another. Preferably, although not necessarily, the differential gripping action is such that a relative lateral displacement between adjacent filaments of the tow is also effected, so that the combination of two transverse filament movements brings about the complete opening of the tow.

Such differential gripping action is achieved by the provision of at least one pair of rolls one of which is smooth-surfaced and the otherof which is grooved over its entire periphery, and preferably by the provision of a plurality of such pairs of rolls arranged in tandem. On each grooved roll, the grooves and the ridges alternating therewith extend obliquely or helically in opposite senses from its center to its opposite ends. Thus, when the tow passes between the two rolls of any given pair of one grooved and one smooth-surfaced roll, some of the tow sections are gripped between the peaks of the ridges of the grooved roll and the outer peripheral surface of the opposed smooth-surfaced roll, while other sections of the tow which are at that time located in registry with the spaces between the ridges of the grooved roll are not gripped between the latter and the smooth-surfaced roll. Generally only one roll of each pair is positively driven while the other is yieldably biased toward it and rotates due to the passing of the tow between the rolls.

Merely by way of example, the foregoing tow opening apparatus may be of the type disclosed in patent The basic process of the present invention further comprises subjecting the opened tow to a spreading operation which transforms the tow into a band or verb of relatively great width, ranging up to as much as 80 inches, or more.

Although the present spreading process may be used to produce webs of varying widths and weights per unit area, it is preferred to produced spread opened tows of not more than about 50 and, in particular,not more than about 35 grams per square meter since such webs are particularly useful as described in detail hereinafter. Obviously, spread tows of greater weight may be obtained by control of the total denier of the starting tow but these lack the highly desirable and unexpected properties of the preferred spread tows. Generally, the present spreading process may be adapted to produce spread tows of a wide range of weight per unit, for example, by controlling the extent of spreading. In its preferred form, this invention contemplates spreading the opened tow to from about 1.5 to about 5 or 6 times the initial width and even wider.

The spreading operation may be effected, for example, by use of a spreading device of any suitable construction.

Merely by way of example, one type of such device comprises at least one and preferably a plurality of arched or upwardly curved bars extending transversely to the direction of movement of the opened tow, in position for the tow to be pulled thereover under predetermined relatively low tension. Spreading may also be accomplished by passing an opened tow of crimped continuous filaments through an air spreader in which the moving tow, in flattened condition, is confined between parallel walls while streams of air or other suitable gas are directed at the tow across its full width. In accordance with this aspect of the patent Invention, it is possible to spread the tow readily, and very evenly, to great widths to produce webs of extreme fineness, such as webs containing less than about 600, e.g. 100 filaments per inch of width, and in which the average air space per fil is appreciably greater than the diameter of the filaments.

The average air space per fil is the average space between the filaments of the web measured on a line in the plane of the web, perpendicular to the longitudinal direction of the filaments of the web, said space being calculated on the assump-tion that all the filaments are arranged in a single plane, with no filaments crossing other filaments. It may be calculated simply from a knowledge of the average diameter of the filaments (Dp), the width (w) of the substantially uniform web and the number of filaments (n) in said width, according to the formula: Average Air Space Per Pll = (w -nDp) - n.

In the prefrerred forms of the invention, the average air space per fil is a plurality of times (e.g. five, ten or more times) as great as the average filament diameter.

While air spreaders or banding jets of the general type employed in the present development have been used previously for "spreading" tows for use in the manufacture of cigarette filters, the art has not heretofore thoughtit possible to use such devices for the formation of webs of low density as here described. Thus in Hacknet et al, U.S. Patent No. 2,774, 680 of December 18, 1956, there is described the use of an "air blast device" which, according to the patent, spreads the tow into a flattened ribbon at "its maximum separation" (column 6, lines 3 and 4 ) , but the data given in this patent clearly shows that the spread ribbon at said maximum separation must have an average air space per fils calculated as described above, of less than zero (the patent gives a spread width of to 6 inches for a tow containing 5,000 filaments of 16 denier cellulose acetate). Similarly, Jackson U. S. Patent No. 2*737,688 describes a tow opening device using air streams impinging on the tow and describes band widths of 6 inches for 80,000 total denier tow, of 5 deniers per filament, and of 25 inches for 5,000,000 denier tow. In contrast, applicant has been able to prepare diaphaneous webs in which, as discussed above, the average air space per fil is well above 10 times the diameter of the filaments and in which the filaments are substantially uniformly distributed across the width of the web.

The relatively dense tow bands produced by air spreading according, to the aforementioned techniques of the prior art do not yield the desirable highl resilient lightweight battings and reinforced laminates which can be made from the webs obtained according to the present invention.

Of the many methods of spreading the opened tow, air spreading is preferred. It has been found that even at high spreading speeds the lightweight web produced by air spreading is a substantially uniform high quality product. In comparison, when curvec bar spreading arrangements (e.g. "umbrella" spreaders) are substituted for the air spreaders, the quality of the product is not as good and the permissible speed of operation is .. .aewhat lower. Thus, if the tow band splits during spreading with the curved bars, the split becomes aggravated as the process continuesj in contrast, air spreading has a self-healing or self-correcting effect so that any split does not continue but instead tends to close up. The use of a system of diverging belts for spreading similarly produces a lower quality product than that obtained when air spreading is employed.

In a preferred form of the invention, the opened tow is passed through an air spreader in which the moving tow in flattened condition, is confined between parallel walls while streams of air or other suitable gas are directed at the tow across its full width. Advantageously, the air spreading is effected in a plurality of stages in each of which he tow is spread to a greater width than in the preceding stage. For best results the tow in any one stage is isolated from the effect of the following stage as by passing the tow between stages firmly in contact with a surface moving at a controlled rate, e.g. around and between a pair of driven nip-defining rolls.

The air spreaders themselves advantageously have air-delivery slits or other suitable openings in one or both of the parallel walls between which the tow passes, said slits leading from a plenum chamber supplied with air at constant pressure. In one highly effective construction there are a series of slits, each running in a direction transverse to the direction of movement of the tow and so arranged that all portions of the tow are subjected to the air streams from said slits. Surprisingly it has been found that even when the width of the air spreader is 8 feet or more, the tow spreads uniformly and the outer edges of the tow, where the resistance to the air would be expected to be less, attain substantially the same density as the central portions of the tow.

In cross-section the air-delivery slits are preferably tapered, narrowing toward their outlets. The tapering may by symmetrical about an axis perpendicular to the face of the web so that the air is blown straight at said face, or the slits may be inclined so that the air imparts a forward or backward force to the moving tow. - b - The pressure in the plenum chamber may vary, one suitable range being about 1 to 5 psig; higher pressures may be used, e.g. 100 psig but these are economically wasteful. The pressure in the tow-confining zone, between the parallel walls, is believed to be little more than atmospheric. When the air is blown straight at the face of the web, the air generally leaves the tow-confining zone from both ends of said zone. Surprisingly little air is needed to expand the tow. Despite the fineness of the webs, the walls of the tow-confining zones of the air spreaders need not be c rrespondinly close together; thus very good results have been obtained with tow-confining slots 1/10 inch in width.

In the early stages of spreading the tow web shows "striations"; that is, there are alternating narrow zones of high fiber density (in terms of the number of filaments per unit of web width) and low fiber density (i.e. visible lean portions) running generally lengthwise of the tow web, but at a slight angle (e.g. 2°) to the precise lengthwise direction. The number of such striations corresponds to the number of lands and grooves on the threaded roll engaged by the tow. It has been found that an additional stage or stages or air spreading, instead of accentuating these striations, eliminates them to a large extent, and that the striations may be removed by permitting the lightweight web to relax, preferably as a continuously moving shallow catenary, after leaving the last stage of spreading. The web is generally under a slight tension during its passage through the air spreaders, such tension being insufficient to remove the crimp in the filaments; on relaxation in the catenary, the crimp in the filaments increases but the width of the web remains the same. The relaxed webs are quite uniform, but often do have some areas of visibly varying fiber density; the uniformity of the latter products is, however, very much greater than that of the commercially "uniform" card webs of staple fibers produced on the most modern carding equipment.

In the fine webs of this invention all the continuous filaments run in the same general direction, lengthwise of the web. However, when one does not look at the whole of a I'ong length of any particular filament, but looks instead at? he individual crimps thereof, it will be seen that most portions of the filament do not run in this general lengthwise direction but instead zigzag back and forth across such general direction. The amplitude of the crimps is such that, for any particular filament, the portion of the crimp at one side (hereafter termed the "crest" of the crimp) overlaps one or more neighboring filaments while the portion of the crimp at the other side (hereafter termed the "valley" of the crimp) overlaps one or more of its neighboring filaments on said other side. This overlap helps to give the webs their cohesiveness. For example, the filaments in the web may have a crimp whose amplitude ( from a median line running in the same direction as the filament) is in the range of about 1/128 to 3/16 inch, said amplitude being measured from said median line to the top of a crest, or to the bottom of a valley. Since there may, for example, be several hundred filaments per inch of web width and since the crimps are not in registry there will be considerable over-lapping of filaments in the web.

When one turns from an examination of the crimps and takes a somewhat larger, though still relatively short, view of the portion of any particular filament which contains several crimps, and which may be for example 1/2 inch to several inches long, it will be found that these portions are not perfectly parallel to the longitudinal direction of the web, but make small angles therewith, which angles change in direction and magnitude along the length of the filament; generally these angles are less than 20°, although for very short portions (e.g. 1/2 inch long) the angle may be larger at times.

It is believed that the overlapping of the crimps and the overlapping due to the presence of the angularly disposed short portions, just described, contribute to the cohesiveness of the web so that, despite its fineness, it can be readily handled as a unitary structure. The degree to which the individual filaments meander by virtue of the presence of said crimps and angularly disposed short portions is not, however, very great; typically, the ratio of the straightened lengths of the individual filaments to the lengths of the same filaments in the web is less than about lf-:l and, preferably, greater than 1.1:1, e.g. about 1.2:1 to 1.4:1. This ratio may be measured by cutting a predetermined length of the web, removing the individual filaments of the cut portion and measureing their lengths while under a tension just sufficient to remove the crimp; the results are then expressed as the ratio between the measured lengths of the individual filaments and said predetermined cut length.

In specifying denier per filament and total denier, the number given herein, with respect to tows and webs, is the denier for the filaments prior to crimping, i.e. the weight of 9000 meters of straight filaments; the weight of 9000 meters of crimped, unstraightened filaments or tow will naturally be greater than these values. With respect to yarns made from the webs, the denier given is based, however, on the actual, unstraightened lengths.

Advantageously, the webs are spread to such an extent that when further spreading is attempted, while the length of the web is kept constant, the web strongly resists such spreading and returns to its previous width.

For example, if a graph is plotted relating the air-pressure in the spreader, as ordinate, to the degree of lateral spreading of the moving web, it is found that there is substantially no additional pressure needed to effect spreading up to a certain width, after which the air pressure required rises sharply. The web density at which this sharp change occurs is termed herein the "Potential Web Density". This Potential Web Density will vary depending on the type =of tow which is employed and particularly on the degree of intermingling and crossing over of the tow filaments. In general, the optimum tows have Potential Web Densities below about 1 ounce per square yard, preferably less than about 1/2 ounce per square yard. Surprisingly, webs of such densities have been found to be easily handled and to maintain their unity without disintegration or splitting during ordinary handling, folding, etc.

In the work on this invention, it has been found that when battings are made of successive layers of spread webs, the battings made from those webs whose actual web densities are below about 1 ounce per square yard have strength and may be handled much more readily without danger of shifting of the layers than battings of the same total weight made from webs of greater densities.

In addition, per unit of weight, the battings composed of the low density webs are thicker and more resilient than battings made up of webs of high density. In general, it is most desirable to use a web whose actual density is less than 4/3, preferably less than 6/5 times the Potential Web Density. The battings made by depositing successive layers of the lightweight webs are very much more coherent than battings made by similarly lapping, card webs of staple fibers.

The webs of spread tow may be laminated to other sheet materials such as woven scrim fabric, or a knitted fabric such as a tricot fabric, or a staple fiber non-woven web, or some other type of backing material such as sponge rubber, leather, paper, plastic sheeting, etc .

The lightweight webs of this invention, particu-larly those produced by the use of air spreaders, are especially suitable for lamination to lightweight paper as by bonding, with a suitable adhesive such as polyvinyl acetate, a single thickness of such a web to a single thickness of the paper. The reinforcement provided by the lightweight web in this use is highly effective while adding little to the cost of the paper, and the side of the laminate bearing the continuous multifilament web has a pleasant soft feel. In one specific example, a spread web of 5 dpf cellulose acetate filaments, said web weighing 3.5 grams per square yard and containing 80 filaments per inch of width, was adhesively bonded to a layer of tissue paper. - m - The webs of spread tow may be formed into battings of any desired thickness by depositing one layer of the web on another as by loosely folding, linearly lapping, or cross lapping the web along its length or by winding the web on itself, e.g. on a round mandrel or on an endless belt. For example, the web, after the relaxing step, may be passed continuously onto a moving endless belt so that it passes all around the belt and builds up thereon until several thicknesses of the lightweight web have been deposited, one over the other, during a corresponding number of cycles of the movement of the belt. Without interrupting the movement of the web or the blet, the deposited layers may be cut through (e.g. along a line just upstream of the line where the web is deposited on the belt), and the resulting multi-layered batt may be pulled from the belt, while a new cycle of deposition and removal begins. In another technique a plurality of relaxed webs may be fed to a zone where they are combined, one on top of the other. The battings may be needled transverse to the planes of the component webs or may be otherwise treated to more firmly bond the filaments in the battings together, if desired. Battings formed of lightweight webs may be employed as stuffings for pillows, comforters, cushions and upholstery, insulating padding, sanitary napkins, etc. without any additional needling or other bonding treatment.

In the needling operation, the batting is generally passed through a needle loom equipped with the usual barbed needles which reciprocate perpendicularly to the face of the batting and serve to move portions of the filaments from each horizontal web upward or downward so that these portions Intermingle with filaments of neighboring webs. The batting is advantageously given several passes through the needle loom and is turned over after each pass. Because of the crimp in the filaments, the filaments can undergo considerable extension into adjacent layers without exerting a contracting effect on the whole battingj in fact it has been observed that the width of the batting may actually increase as a result of the needle punching. The needle looms used may be those commercially employed in the needle punching of staple fiber battings.

The present lightweight webs especially when made by air spreading are particularly suitable for the manufacture of yarns. The number of filaments per inch of such webs is low and the webs are relatively uniform, making it relatively easy to subdivide the web into a series of narrow bands each containing the desired number of filaments. For example, when the filaments are of cellulose acetate or similar material, the subdividing can be effected by a series of hot wires each running perpendicular, or at another suitable angle, to the plane of the web which wires are spaced at predetermined points across the width of the web. For example, with a web which has been spread until it contains some 128 five-denier cellulose acetate filaments per inch of width, 640 denier yarns may be obtained by spacing the hot wires one inch apart and, if desired, twisting the one-inch cut bands to give them a more rounded shapes for instance, a twist of 1/4 to 10 turns per inch may be inserted, depending on the size of the yarn and the desired end use. As mentioned previously, there are portions of filaments which cross other filaments and which are arranged at small angles, both left and right, "V- · to the general direction of the filaments of the spread web.

The hot wires will of course cut through these filaments so that the resulting yarn will have some filament ends, giving some of the effect of a staple fiber yarn. Because of the deregistration of the crimped filaments in the web, the yarns produced in this manner are very bulky. When the webs are made of filaments of high tenacity, e.g. tenacity above 2 grams per denier, such as is the case with filaments of terephthalate esters, it is advantageous to use devices 0 other than hot wires for the cutting. Thus a series of anvil rolls of known type, comprising rotating shearing discs mounted alternately on parallel axes with the sides of the discs in close contact, and having a scissors-like effect on those filaments which pass between the rolls, may be employed. For example, a spread web having, per inch of width, 850 filaments of polyethylene terephthalate of 3 dpf, may be fed to anvil rolls arranged side by side to cut said web into strips each one inch wide and said strips may be wound up,as on a ring spinner which inserts a twist of 1½ 0 turns per inch, to form a hairy, bulky, v,j¾ry strong 2660 denier yarn (the figure for denier of the yam is based on the actual length of the crimped yam, not on the straightened length). The anvil roll arrangement may also be used for slitting webs of weaker fibers! it gives a product free from the occasional fused zones which may be formed when hot wires are used on thermoplastic filaments such as cellulose acetate.

The lightweight webs may be readily converted into foraminous fabrics, like scrim fabrics, rapidly without the need for any preliminary formation of yams or for any knitting, 1 0 knotting, weaving or other systematic ya entanglement. This p.p Po tffacted Pn a Ptahly effloiappf P«?||» ¾f ItO tfg ®t filament a. s a locations m im mMf #i§ >§ϋΙβ l? of i¾e poo, ao aa to laaoaa ¾a ||i pti §; ,^ϋ§#¾ til ff|l ttpprt ar# ipHie o adnop apaaoo t% MM § a ilii p nimmit®» ia too *i »| ¾^ι #if || If ¾ Ipf than the a*sii|« M ittiilif if ii§ ¾tf|t β# ne PPtaap in ahleP %h® filamau # i f If w 4to»M| grea than the avpra§p fpla p i fi| #f |§ p#Ps fpia a tarn In the apt 5$ n& * or ipt^ a m i It or li« easa en j in aipp spitpilpP ¾f |fip$ §§ t l i§ Ona fca Pnl iio for introducing fti §&$t#l$| i# %pv ¾ oiPl ha pab under teooion O¥PP a *&$$$ iilip i|»i upmip pi p poad pro jaofciapa, fht toiitlp a w 1 tho filpmanta iota f a s aces batpopn f½$ f«|»#iOt|* ItwlPg o enin in the pab ppspe ph fP¾jPP p|§ tpp ugh the web, ¾hile the boat of bpp pa atti fef f$i** menfep into tnair nea a on figuratio s, It t¾i§§ ¾ t Hl pa terping operation oan he ogrriad out t ti * Mf* O Ploplsrl oinoa the aeea of thia iuvantt n l« i¾f^f# f§t raadlly to o era io s mder the hlglt Pel ffS| it§ ti§ §llf aapooipteP aith the high spaed opppptlof-p Bp var ing the aheoe and a aaip o Ptip iPPj^tfl^ the pa ft a. an aao -aaa r ptor of the reapltipi nat pf¾ ni S oharaetar of the res lting pattepned na my ft* eiifiit , ffcpp there y fca emplo ed, for e¾ppifllp* psjpppip i #lf| pre pypamidal or f ro^h -eanioali feh® pt^eettai ¾ m¾l parroptng toaardo thei outer r ions to fepslli P e t rat loo of the not and spreading of e bp top the openirp^a In t o aeb, An p.rmr¾$m# $ of ^mPt y projections may be used to produce a web having substantially square openings, very much like a square woven open-weave fabric. Similarly, an arrangement of frustc-conical projections may be used to form a web in which the holes are round or oval, while the use of a drum having a web-engaging surface with elongated projections, such as may be obtained by wrapping the drum with a stiff woven wire screen, will produce elongated holes or slits.

The openings in the web may be produced in other ways than by contact with solid penetrating elements. For example, the web may be passed through a zone where a patterned series of spaced jets of a suitable fluid (e.g. air or water) are directed against it to drive the portions of the filaments engaged by said jets toward the spaces between jets, as by passing the band around a perforated drum and blowing air through the perforations in the drum.

The number and size of the openings may be varied as desired. For example, there may be about 10 to 100 openings per square inch, with the diameter of the openings being in the range of 1/10 to 1/3 inch.

The setting of the patern in the web may be effected by heat, preferably sufficient heat is used to adhere the filaments together. However, when the web contains those types of thermoplastic filaments which may be heat-set into a permanently bent condition, such as polyethylene tereph-thalate, a patterned structure may be attained by such heat-setting without surface adherence. To promote surface adherence, particularly for filaments of relatively high softening temperature, &the web may be treated to bring its filaments into potentially adhesive condition, as by the application to the web of a heat-activable adhesive or a plasticizer which serves to lower the softening temperature of the filament surfaces. Such treatment is preferably effected prior to the patterning step, but it may be effected simultaneously, or subsequent to, that step.

It is advantageous to stagger the openings so that the filaments which normally run longitudinally of the web may distribute themselves uniformly about the holes, and the deviations of the filament direction caused by the formation of the openings may be substantially the same for all filaments. It will be appreciated that this deviation from the usual filament direction causes an overall shortening of the web when it is treated to form the pattern of openings.

In the formation of the foraminous fabrics, the degree of eoalescene of the filaments may be controlled as desired. Thus, when a limited amount of plasticizer or other bonding agent is used and the processing, tension is controlled so that the crimp is not pulled out of the filaments during the patterning step, there will be contact between the filaments only at spaced points, because of the deregistered crimp, and the bonding of the filaments will occur only at such spaced points. For instance, to a web of crimped cellulose acetate filaments there may be applied 6# of the known plasticizer, triacetin, and the patterning and bonding may take place at 325°P.

Foraminous fabrics, of this invention, may be employed for such articles as bandages, towels, filters, diaper materials, sanitary napkin cover fabrics, dust cloths.

In one particularly suitable system the adhesive, plasticizer or other bonding agent is applied by means of rapidly rotating discs mounted with their axes parallel to the direction in which the web is travelling, and with the discs themselves in planes perpendicular to the plane of the web. The edges of these whirling discs dip continuously into baths of bonding agent and then, by centrifugal action, cast a very fine spray of tiny droplets of the bonding agent uniformly at the surfaces of the webs. This spray, unlike that from the usual spray guns, is not associated with any substantial blast of air and does not blow the diaphanous web from its straight paths accordingly, it produces a more uniform and controlled application of the bonding agent. It will be understood that th same method of application may be employed when the web carrying the bonding agent is to be used for laminating, as previously mentioned. Furthermore, a composite fabric may be made by bonding a foraminous fabric, made as described above, to a lightweight web to produce a dimensionally stable lightweight structure having a soft surface, such products being suitable for use as sanitary napkin covers, bandages, decorative fabrics, etc. Thus the imperforated web may be treated with a bonding agent such as a plasticizer and then brought into close contact, underpressure if desired, with the foraminous fabric and heated to cause the web to adhere firmly to the fabric . Alternatively, the bonding agent may be applied to the fabric only, or to both the web and the fabric, or the bonding agent may be applied only to discrete spaced areas.

The invention will be illustrated particularly with respect to tows whose filaments are of polyethylene tereph-thalate or of cellulose acetate (of the usual acetyl content, e.g. about 5^-55$ calculated as acetic acid). It will be understood that it is within the broad scope of the invention ■V- to carry it out with other tows, such as those made of other polyesters (e.g. the polyesters of terephthalic acid and other glycols such as dimethylol cyclohexane), linear super- polyairides (such as nylon 6 or nylon 6, 6) , polyacrylonitrile 5 and copolymers of acrylonitrile, olefinic polymers and copolymers, e.g. isotactic polypropylene, other organic derivatives of cellulose such as esters and/or ethers of cellulose, for example cellulose propionate and cellulose acetate propionate or the like, highly esterified cellulose 0 containing less than 0.29 free hydroxyl groups per anhydroglucose unit such as cellulose triacetate, rayon (regenerated cellulose). The number of filaments of the starting tow can vary within wide limits and may range up to as high as 1,000, 000, with a denier per filament as high 5 as 25, e.g. 1 to 20. The number of crimps per inch of tow may range up to as high as about 80, but for most end products to be described herein about 3 to 50, preferably about 3 to 20 crimps per inch of starting tow are found sufficient. 0 The foregoing and other objects and characteristics of the present invention, as well as the advantages accruing therefrom, will be more clearly understood from the following detailed description thereof when read in conjunction with the accompanying drawings, in which: Fig. 1 is a schematic illustration of one type of apparatus which may be employed in transforming a coherent continuous filament tow into the form of a non-coherent spread band of substantial width; Pig. la is a view taken along the line la-la in 0 Pig. 1 and shows details of a part of the crimp-deregistering means of the appartus of Fig. 1; Pig lb is a view taken along the line lb-lb in Pig. 1 and shows, in perspective, the filament spreading means of the apparatus of Pig. 1; Pigs. 2 and 2a are schematic illustrations of apparatus for applying a bonding agent to spread tow bands or webs formed by the apparatus of fig. lj Pig. 3 is a schematic illustration of ah apparatus for producing a pleated or corrugated web from spread tow to which a bonding agent has been applied; Fig. 4 is a plan view of a band or web of spread tow to which a bonding agent has been applied in the form of discrete dots or small areas; Pig. 4a is a fragmentary schematic illustration of one type of bonding agent applicator which may be employed in the apparatus of Pigs. 2 and 3 for producing the band shown in Pig. 4; Pig. 5 is a schematic illustration of a apparatus for treating a band or web of spread tow, as produced by the apparatus of Pig. 1, so as to divide the band into a number of strips of lesser widths Pig. 6 is a schematic illustration of an apparatus which may be employed in folding, i.e. linearly laying or cross-laying the band or web of spread tow produced by the apparatus of Pig. 1; Pig. 7 is a schematic illustration of an apparatus which may be employed to laminate the band of spread tow produced by the apparatus of Pig. 1 with one or more additional webs of sheet material; Pigs. 8 and 9 are schematic illustrations of apparatus which may be employed in needling or stitching a band or web of spread tow produced by the apparatus of Pig. lj Pig. 9a is a view taken along the line 9a-9a in Figs. 8 and 9; Pig. 10 is a schematic illustration of an apparatus which may be employed in severing a band or web of spread tow into sections of suitable lengthj Pig. 11 is a schematic illustration of an apparatus for laminating to one another a plurality of webs or bands of spread tow treated by the apparatus of Pig. 6; Pig. 12 is a schematic illustration of an apparatus for laminating to one another a pleated or corrugated web and a pair of plane webs or sheets; Pig. 13 is a diagrammatic representation, on an enlarged scale, of a portion of the composite fabric body produced by the apparatus of Pig. 12.

Pig. 14 is a schematic view of a tow-opening and air spreading process! Fig. 15 is a cross-sectional view of an air spreader; Fig. 16 is a view showing the arrangement of the openings of the air spreader; Fig. 17 is another view showing the overall arrangement of the slits of the air spreader; Fig. 18 is a view similar to Pig. 17, but showing an alternative arrangement of the slits; Pig. 19 is a schematic view showing a process for the production of pillows; Fig. 20 is a schematic view showing a process for laminating the lightweight webs to a web of paper; Pig. 21 la a schematic view showing a process for the production of scrim fabric from a lightweight webj Pig. 22 shows details of the surface of a roller for use in perforating a lightweight web for the production of a scrim fab ic Pig. 23 is a schematic view of a process for splitting lightweight webs to form a plurality of yarnsj Pig. 24 is a plan view of a portion of the apparatus Pig. 25 is a schematic view of a process for combining a lightweight web and a card web of staple fibers; and Pig. 26 is a schematic view of a process for cross-lapping a lightweight web to form a batting followed by needling of the batting.

Fig. 27 is a schematic elevational view of one form of a tow opening apparatus with a preferred modification as described more fully hereinafter.

Fig. 28 is a schematic view of a preferred process for the manufacture of pillows.

In Pig. 1, the continuous filament tow 10 is taken from a bale or package 11 and fed in any suitable manner across a guide 12 through a banding jet 13. In this Jet (which may be omitted, if desired) the tow is subjected to the action of compressed air, whereby the normally ropelike tow is formed into, a relatively narrow flat band.

Upon leaving the jet 13, the tow 10 is subjected to the action of a tow opening device 14 which preferably includes a plurality of pairs of parallel and coextensive rolls 15 and 16 arranged in tandem and between which the tow is passed. As clearly shown in Pig. la,' the roll 15 of each pair is provided with two sets of oblique ridges and grooves 15a and 15b which wind in opposite senses helically about the roll from the center thereof and toward its opposite ends. The roll 16 of each pair is smooth-surfaced and preferably has its outer surface defined by a sleeve of rubber or like resilient material of suitable hardness surrounding metallic core.

Although Pig. 1 s^hows only two pairs of, such rolls 15 and 16, it is to be understood that in actual practice only one pair or as many as three or more pairs of rolls may be used, depending on the physical characteristics of the filamentary tow being processed.

As previously explained, the function of the pairs of rolls 15 and 16 is to subject the initially coherent tow to a differential gripping action, either while it is under a predetermined amount of tension or while it is maintained in a relatively slack condition, so as to effect a displacement of the various filaments making ip t¾© toW both longitudinally and transversely or laterally relative* to one another. In this manner, the crimps of the various filaments are separated from and deregistered with respect to one another, yielding an opened tow band which is somewhat wider than it was upon leaving the banding jet 13· Although the precise width of the tow band leaving the device l4 will vary with the operating characteristics of the said device, it is found that the tow at this stege is generally approximately 2 to 40 inches wide.

Upon leaving the device 14, the opened tow band is passed under suitable tension of less than about 10 pounds over a spreading device 17 in which the width of the band is increased considerably to the desired value.

The spreading device 17 which is employed in the apparatus of Pig. 1 is diagrammatically illustrated in Fig. lb and comprises a plurality of upwardly arched or curved bars 17a to 17e of progressively greater length supported at their opposite ends by a pair of elongated diverging frame members 17'. For obvious reasons, the spreading device 17 is positioned so that the shortest bar 17a, the length of which is approximately equal to the width of the opened tow 10, is closest to the exit end of the tow opening device l4. The arrangement is such that as the band of filaments is moved across and in c ontact with the bars 17a to 17e, its width will be considerably increased, until the ultimate band 10» is as much as 80 inches or more wide.

As previously intimated, however, the spread filament band may be subjected to one or more of a number of finishing treatments designed to prepare the band for ultimate use in the manufacture of a great number of different end products. Both the nature and complexity of the said finishing treatment will, of course, vary with and depend upon the type of filaments being processed, the type and desired physical characteristics of the end products to be made, and the characteristics (mechanical and/or chemical) of the ancillary agents, materials and devices employed in the performance of such treatments. Details of these parameters for different applications will be more fully indicated as the description proceeds.

To unify and stabilize the spread filament band without recourse to auxiliary sheet materials, the band » of Pig. 1 is passed through an applicator device 18 (Pigs. 2 and 2a) in which a suitable bonding agent is applied to the band. Although not expressly illustrated, the means for applying the bonding agent to the band of filaments may comprise either a spray system or a bath or a roll system, and may be designed to apply the bonding agent to either one or both surfaces of the moving band. It will be readily understood that the bonding agent may be a plasticizer or solvent for the thermoplastic material of which the filaments are composed, or a suitable adhesive composition which is compatible with the thermoplastic material. Por cellulose acetate filaments, for example, a plasticizer such as triethyl citrate, diraethoxy ethyl phthalate, methyl phthalyl ethyl glycolate and: glycerol' triacetate (triacetin) or a solvent such as acetone may : be employed, while for polyester filaments such substances as chloral hydrate and certain synthetic polymer emulsions are found highly efficacious.

Most preferably, in order to enable maximum possible production rates to be attained, the bonding agent should be of a quick-setting or quick-drying type. In this connection, the web or band of filaments upon leaving the device 18 may be passed through a heater-dryer cabinet 19 (see Pig. 2) or the like, or (see Pig. 2a) it may be passed over an open air framework 20 (if the bonding agent is of the air-drying type), preparatory to being fed to the take-up . location 21. The total amount of bonding agent applied per unit area of web may range from about 2$ to 200$ of the dry base weight of the web or band and advantageously is limited to between about 5$ and 100$ so as to ensure adequate control over and substantially complete attainment of the ultimate properties desired in the various end products. The base weight of the web or band will depend principally on the initial character- istics, i.e. total denier and denier per filaments, of the starting tow, and on the degree of opening and spreading thereof. For all practical purposes, the speed of movement of the web or band from the bale 11 to the take-up location 21 during any given run will be determined in accordance with and limited only by the requirements of the bonding agent applicator and drying means.

As shown in Pigs. 2 and 2a, the stabilized band or web 10" of filaments in its flat state may be wound into a roll while awaiting further use. In such a case it may be found advisable to roll the stabilized filamentary material up with a sheet of anti-sticking or release paper or the like which prevents the convolutions of the filamentary material from adhering to one another while in storage. Alternatively, of course, the stabilized fila- mentary material may immediately upon leaving the drying zone 19 or 20 be taken up into any desired form, i.e. roll or otherwise, necessary for the making of the ultimate end product. The filamentary material 10" may be employed advantageously in theManufacture °f industrial air and liquid filters, bale strapping, fabrics capable of being molded or calendered, etc., i.e. products as to which substantial tensile strength and the ability to retain shape are important characteristics.

Where a more bulky base material is desired, the manner of treating the filamentary web 10' illustrated in Pig. 3 may be employed. In this arrangement, the web 10' is fed by feed rolls or the like into a stuffer box 22 at the entrance opening of which the web is acted upon by any suitable type of reverse folding means, e.g. a pair of alte natingly reciprocating bars 23> a star wheel folder (not shown) or the like. The initially plane web is thus transformed into a pleated or corrugated structure 24 which, as it passes through the stuffer box, is compacted until , it emerges as a considerably bulkier web 24· which is highly suited for use as batting or padding in a great variety of products. Preferably the discharge section 22' of the stuffer box is heated by any suitable means (not shown). The unbonded filamentary web 24 may thereby be stabilized in its pleated form 24« by causing the filaments either to set or to become fused to one another at their points of intersection. If the web was previously passed through a bonding agent applicator device l8 (indicated in phantom outline in Pig. 3)* then the heater section 22» acts to stabilize the web 2 ' in the same manner as the heater-dryer 19 shown in Pig. 2. The final stabilized web may thereafter be taken up for storage or immediate further processing as desired. Several types of such further processing will be described presently,, It will also be understood that a plurality of individually spread and either bonded or unbonded tow bands 10" (not shown) could be cascaded or fed simultaneously into the staffer box 22 at preselected relative speeds, in order to facilitate the exercise of a precise control over the base weight of the ultimate web 2 ", For certain applications, it is found desirable to apply "the bonding agent in the device 18 only to a predetermined fraction or percentage of the total area of the band 10' . To this end, the applying means in the device 18 may comprise (see Fig. 4a) a system of applicator rolls 25 and 26 between which the band or web is passed. The roll 25 is smooth-surfaced, but the roll 26 coacting therewith is of the intaglio type and in the illustrated example is provided with a plurality of raised portions or projections 26a of preselected configuration, here circular cross-section, and distribution. The bonding agent 27 is applied to the roll 26 from a reservoir 27a by a set of transfer rolls 28. The non-woven, oriented continuous filament fabric, produced in this manner is diagrammatically illustrated in Fig. 4, wherein it is seen that the bonding agent is distributed across the expanse of the filament band 10' in the form of a plurality of discrete dots or circular areas 27 ' arranged in a plurality of tr :ually perpendicular rows and columns. The dots or areas 27 ' in any given row or column are staggered with respect to the dots or areas in the next adjacent row or column, and each two adjacent dots or areas of each row extending crosswise to the filament orientation overlap slightly the loci of the lateral boundaries of the dots or areas of the intermediate column extending lengthwise of the filament orientation.

The novel, continuous filament fleece-like fabric formed by this "spot-bonding" technique is possessed of excellent textile properties such as softness or hand, flexibility or drape, and the three dimensional appearance or loft characteristics of woven fabrics. Since the bonding agent is applied to only a predetermined fraction of the total surface area of the original web 10', the fabric is rendered diraensionally stable while still being fully flexible in all directions. High softness fleece fabrics of this type are particularly advantageous for the manufacture of a great number of personal products such as surgical 'dressings, disposable table napkins, hand towels, diapers, and the like, as well as to other products such as casket liners, pre-opened balable cigarette filter materials, specialty cloths for curtains, etc.

As previously indicated, the dry base weight of any filamentary web 10* depends in essence on the initial total dfenier, denier per filament, degree of crimp, extent of opening and extent of spreading of the starting tow. In actual practice, the take-off end of the spreading device will generally be 80 inches or more in width. Thus, assuming a starting tow of specified total denier, denier per filament and number of crimps per inch, the lowest possible base weight can be achieved only by spreading the tow to the maximum possible extent. To facilitate the direct production of filament webs of substantially lesser width but of the same base weight from the same or an identical starting tow, the present invention contemplates the subdivision of the maximum width band or web of filaments 10' into narrower bands 29 (see Pig. 5, for example). This goal may advantageously be attained by employing either a set of hot slitting wires (not shown) intersecting the path of movement of the web substantially perpendicularly to the plane therof, or a set of high speed rotary cutters or slitters similarly positioned, e.g. by being mounted on a common rotary shaft (not shown). Devices of these types are well known,particularly for use in the cutting of plastic sheet material into strips, and thus need not be more specifically illustrated or described herein.

In accordance with another aspect of the present invention, the division of the large width band or web of filaments 101 into the desired narrower bands 29 may advantageously be achieved by an apparatus constructed essentially in the manner illustrated only schematically in Fig. 5. Such an apparatus preferably comprises a housing made of plastic or like insulating material through which the web or band 10» is to be passed. The exit opening for the web 10· is defined by an elongated slot 30a dimensioned to permit free passage of the filamentary web. Rigidly secured to the housing 30, as by being embedded in the plastic material therof, along the top and bottom edges of the slot 30a are two sets of small metal bars or plates 31 and 32. These elements are arranged in vertical pairs and are connected with suitable means (not shown) adapted to apply electrostatic potentials on the order of 100,000 volts or more to the respective pairs of plates 31 and 32.

The electrostatic fields so generated across the slot 30a collect the filaments into the desired plurality of relatively narrow bundles or bands 29. Straying filaments between the segmental bands 29 may be eliminated by the provision of suitable rotary cutter means (not shown) positioned adjacent the slot 30a.

Each of the so-formed bands 29 may be processed and subjected to a finishing treatment as described hereinabove with respect to the spread tow band 10», e.g. the application of a bonding agent. By virtue of their reduced dimensions, however, the bands 29 lend themselves readily to the formation of other products. Merely by way of example, these bands may be twlsted to form ropes. The twist may, if desired, be set or fixed either by application of a bonding agent or, if the filaments are of heat-settable materials, by a heat setting treatment. The bands may also be formed into yarns, either with zero twist or with a conventional twist of 1 to 50 turns per inch, which yarns, due to the presence of the crimps are found to possess a stretch property useful in a number of garment constructions. The low twist yarns especially make excellent bulky carpet yarn when possessed of a saw-tooth crimp.

In accordance with still other aspects of the present invention, a variety of different products may be made from an opened and spread, oriented filament tow as taken off in the form of a web or band 10' of considerable width from the spreading device 17. Merely by way of example, the said web 10· may be fed to a folding or lapping device 33 (see Fig.6) mounted for reciprocal movement above the upper reach of an endless conveyor belt 3^ on any suitable track or rail structure 35. The device 33 may be reciprocated along the track structure 35 either in a direction parallel to the direction of movement of the belt 3^·, as indicated by the double-headed arrow A, or in a direction transverse to the direction of movement of the belt, i.e. at an angle of up to 90° thereto as indicated by the double-headed arrow B. In either case, suitable means (not shown) are provided for controlling the speed of movement of the device 33 relative to the speed of advance of the belt 3½ . By virtue of such an arrangement, the web 10' is deposited on the upper reach of the belt in the form of a continuous multiply web structure 36. If the device 33 moves parallel to the belt 3 , the filaments in each ply are all oriented lengthwise of the web and thus linearly in the direction of advance of the web, whereas if the device 33 moves transversely to the belt, the filaments in each ply are oriented angularly to the direction of advance of the web and, of course, angularly relative to the filaments in the next adjacent plies. The number of plies per unit length of web 36 or the angle of cross-lapping will be determined by the relative speeds of movement of the belt 3^ and the laying device 33 and by the angle between the direction of such tranverse and the direction of movement of the take-up belt.

The multi-ply web structure 36, whether of the linearly lapped or cross lapped type, leaving the apparatus of Fig. 6 may be subjected to still further treatments so as to adapt it for use in the manufacture of particular end products. Thus, the multi-ply web 36 may be immediately taken up in any suitable form, e.g. a roll, for the actual product- making operation. For obvious reasons, of course, if a linearly lapped web 36 is to be shaped into a roll, it can only be rolled up lengthwise, i.e. about an axis perpendicular to the filament orientation. On the other hand, a cross lapped web may, due to the bias laying of the plies therof, be rolled up either widthwise or lengthwise. Loosely taken up webs of these types, i.e. webs which have not been treated for external dimension stabilization, are found particularly useful in relatively static products, such as battings or stuffing for pillows, comforters, cushions and upholstery, insulating padding, sanitary napkins, etc.

Where a greater degree of dimensional stability is required, the lapped web 36 may be passed through a device of the type designated 18 in Pigs. 2 and 2a to permit a bonding agent to be applied in any suitable manner, for example by spraying or the like. If desired, the web may be "spot bonded" as indicated in Pigs. 4 and 4a. It will be readily understood, moreover, that the bonding agent may be applied to the opened and spread tow 10" prior to the linear or cross lapping of the latter, which would ensure the bonding of the filaments not only at the outer faces of the lapped web 36 but also at the contacting faces of adjacent plies thereof.

For cases in which the use of a bonding agent is deemed .undesirable or incapable of imparting to the ultimate end product the desired physical characteristics, the lapped web 36 may be fed into and through a stitching and/or needling device 37 (Pig« 8) or 38 (Pigo 9) in which the web is stitched or needled either cross-wise at regular intervals, as indicated at 39 in Pig. 8, or in a single or multiple zigzag pattern as indicated at 40 and 40a in Pig. 9. For this type of operation, the web 36 is being fed into the stitching or needling device is generally first passed through a slack-absorbing mechanism, shown diagrammatically in Figs, 8, 9 and 9a to comprise a set of three guide rolls 4, 42 and 3, the middle roll 42 of which is mounted for vertical displacement toward and away from the stationary rolls 4l and 43 > as indicated in broken lines in Fig. 9a. Movement of the roll 42 out of its solid-line position permits slack in the web 36 to be taken up while the web is stationary or moving at a reduced speed in the needling or stitching device 37 or 38 during the operation of the latter. It will be understood that the staggered zigzag needling or stitching of the web, indicated at 40a in Fig. 9, may be employed to achieve a quilting effect.

Diraensionally stabilized lapped webs 36 are found particularly useful in the manufacture of products designed for relatively dynamic applications, such as dry and wet mop heads; buffing, polishing, cleaning and abrading pads; air, gas and liquid filters; reinforcement webs for other types of relatively weak or unstable sheet, material and especially for conventional unbonded non-wovens; industrial belting and carrier webs; bale strapping; outer wear and interlining fabrics; blankets; papermaker5 s felts; and the like. Stabilized webs are not limited to such products, however, and may be employed in static applications of the types enumerated hereinbefore in connection with the un-stabilized lapped webs.

The present invention sbill further contemplates the lamination of webs of opened and spread tow, both of the single-pay type identified by reference numeral 10' and of the multi-ply type identified by reference numberal 36, with one or more additional layers of identical or different sheet material. As shown in Pig. 7, the filament web 10' or 36 may be fed in the direction of the arrow C toward a pair of calender rolls 44 and 45 to which is simultaneously fed another sheet material 46 taken from a supply roll 47. In the Illustrated embodiment, the sheet material 46 is first passed over a guide 48 to an applicator roll system 49, where a suitable bonding agent is applied to that one of its faces to be contacted by the web 10' or 36, prior to reaching the calender 44-45. Merely by way of example, the sheet material 46 may be a woven scrim fabric, or a knitted fabric such as a tricot fabric, or a staple fiber non-woven web, or some other type of backing material such as sponge rubber, leather, paper, plastic sheeting, etc. At the same time, the web 10' or 36 may be In an unstabilized state or may have been stabilized as hereinbefore described. Sinoe the web 10' or 36 and the coated sheet material 46 jointly enter the nip of the calender rolls 44 and 45, they are oombined into a unitary laminar structure 50 whioh may then be taken up for storage or further use in any desired manner.

It will be understood that the sheet material 46 may be, rather than a woven or knitted or staple fiber non-woven fahrio, a web of opened and spread tow similar to the web 10· or 36. Thus, either or both of the webs may be a single-ply structure, either or both of the webs may be linearly or cross lapped, and either or both of ¾he webs may have been previously stabilized by prior bonding, needling or stitching, or laminating operations. Especially where both webs are of the same type, i.e. both are linear lapped or single-ply, it is preferred in accordance with still another aspect of the present invention to laminate them with the respective filament orientations of adjacent web sections transverse, e.g. at right angles, to one another.

In such a case, of course, the respective endless webs must be cut or otherwise formed into the shape of identical sections so that each pair or multiplicity of sections can be laminated individually after being appropriately cross-plied.

As previously indicated, the laminating operation may involve more than two webs or sheets. This is diagram-matically illustrated in Pig. 11, wherein three webs X, Y and Z are being laminated. Thus, the three webs may all be single-ply opened and spread tow bands 10', and prior to lamination are fed through respective laying devices 5 * 52 and 53. Fo example, the devices 51 and 53 may produce linearly lapped webs, while the device 52 produces a cross lapped web, or vice versa. The resultant webs X», Y1 and Z' may then be fed to a pair of calender rolls 5 and 55 and thence to a stitching or needling device 6 which may operate in the manner illustrated in Pig. 8 and 9* stitching or needling in parallel rows or in single or multiple zigzag lines, so as to produce different stitching or needling patterns as desired, e.g. a quilting of the laminar structure. If necessary, the devices 51* 52 and 53 could be bonding agent applicators either alone or in conjunction with linear and cross lapping means as previously described. Alternatively, the webs X and Z could be continuous filament tow opened and spread and, if desired, otherwise treated as hereinbefore set forth, while the web Y may be a conventional staple fiber non-woven sheet or a woven or knitted fabric, or the web Y could be a continuous filament spread tow and the webs X and Z either a natural or synthetic fiber woven or knitted fabric, e.g. cotton cheesecloth, nylon fabric, cellulose acetatetricot fabric, or the like. In any of the foregoing cases, X, Y and X may each be composed of a plurality of webs or laminar structures arranged in any preselected manner.

Similar to the foregoing, a laminar structure may be formed with a pleated web 24» of the type illustrated in Pig. 3. This is best shown in Pig.

The bonded or unbonded spread tow band 10 ! is, as before, fed by means of feed rolls or the like into the stuffer box 22 through the folding means 23, and simultaneoulsy therewith two bands of sheet material 46« and 46" are fed into the stuffer box at the opposite sides of the loosely pleated web 24. The sheet materials 46' and 46" may be scrim fabrics or otherwise the same as any of the various types designated hereinbefore by the reference numberal 46 in Pig. 7. It will be apparent, therefore, that as the web 24 advances through the narrowing, funnel-like stuffer box into the heater section 22» of the latter, it is compacted to form the web 24' while at the same time the bands of sheet material 46* and 46" are passed into intimate contact with the opposite faces of the said web 24' . In general, either the web 10» is previously passed through a bonding agent applicator device 18, or the bands 46" and 46" are passed through respective applicator roll systems 49 (the device 18 and roll systems 49 in Pig. 12 are shown only in phantom outline to indicate that only one or the other thereof Is used in any given case), so that a secure bonding of the said bands of sheet material to the web 24» is effected in the heater section 22' .

The resultant composite fabric structure, an enlarged fragmentary section of which is illustrated in Pig. 13, is then ready to be taken to any suitable take-up location for storage or further treatment. It is to be understood, of course, that in the system of Pig. 12, within the purview of the present invention, a plurality of spread tow bands or webs 10' may be cascaded into the stuffer box to be sandwiched between the opposed bands of sheet material 46» and 46", or a single such band of sheet material may be employed and laminated to only one side of the pleated web 24-τ24' which may be of a single web 10» or a plurality of such webs cascaded as before described. In any event, the speed of operation of the folding means 23 and the relative feed rates at which the web 10' and the band or bands 46« or 46" are delivered to the stuffer box 22 determine the ultimate base weight, i.e. mass per unit length, of the final laminar structure.

Laminar structure of any of the type described are found to be highly suitable for the making of a great variety of products, some of which fall into the same classes as those made from otherwise treated, non-laminated opened and spread tow. Among these are such as automotive fabrics, tire chafer cloths, furniture and pillow batts, interlining, insulating batting, wall board reinforcement and covers, filters, blanket and clothing fabrics, packaging materials, laminated textiles, carpeting and underlay pads, imitation leather, etc.

A web W formed in any of the hereinbefore described ways may be further treated in the manner illustrated in Pige 10 by being fed to a cutting or severing mechanism 57 in which the web can be cut into suitable lengths. Merely by way of example, such an apparatus may comprise a pair of endless belts 58 and 59 the upper reaches of which are substantially coplanar with one another and the adjacent ends of which are spaced to permit vertical reciprocation therebetween of a pair of cooperating knives or cutting members 60 and 61. The apparatus is preferably associated with an expander 62 constructed to take up any slack in the web being fed through the cutter which would result from halting the feeding movement of the web during each cutting operation.

Pigs. 14-28 are described in detail in the following examples which are illustrative of the preferred forms of the present invention.

EXAMPLE I A polyester continuous filament tow having a total denier of 220,000 and a denier per filament of 5.0 was processed through a tow opening and crimp deregistering apparatus of the "threaded roll" type disclosed in *he Israel Patent No. 19500,. . . he^eiRb»£©ia©-me»ii©»ed-pEic-n-applica±iQnT said apparatus having a first pair of rolls operating at a speed of about 19.5 meters per minute, and a second pair of rolls operating at a speed of about 27 meters per minute e The resulting opened tow was in the form of a band about 30 cm. wide.

Thereafter, the opened tow was passed under a tension of approximately 230 grams over a spreading device (such as 17 in Fig. 1) consisting of 2 curved bars. The spread tow band was approximately 100 cm, wide and had a base weight of about 28 grams per square meter. The web so formed was fed to a laying device and there formed into a multi-ply cross lapped structure. The latter was then rolled up to form a pillow batting having a weight of 366 grams and was found to be characterized by compressibility and recovery properties comparing favorably to conventional staple fiber pillow batts.

EXAMPLE II The process of Example I was repeated except that the spread tow bard was linearly lapped. Pillow battings formed from about 2-3m.. layers of this material and weighing 366 grams each were found to be markedly superior to staple fiber pillow batts in terms of compressibility, recovery, softness, bulk, fluffability and durability.

EXAMPLE III A polyester continuous filament tow having a total denier of 225,000 and a denier per filament of 5.0 was processed on the "threaded roll" tow opening device as in Example I and thereafter spread to form a band ihaving a width of gpp-poximately 7© cm. and a base weight of about 35 grams per square met . prior to being linearly lapped. Sixteen web segments of this band were then plied together, as follows; four webs with filaments oriented in one directions atop these, eight webs with their filaments arranged crosswise to the filaments of the lower websj atop these, four webs with their filaments parallel to those of the bottom webs. This structure was then needled in a plurality of passes in the direction of the filaments of the top and bottom webs at 400 strokes pe minute, with 8 needles per square inch and a 0. /+-c<fl- batt progression between successive strokes. The needling apparatus was set for penetration of the needles into the batt to depths ranging from 1 6 to 1,9 cm. from the opposite faces of the laminate. The resultant continuous filament tow batt was found to compare favorably with a needled staple fiber batt of corres-ponding dimensions with respect to the properties of bulk, thickness, flat abrasion resistance and air permeability.

The needled tow batt was further found to have as much as 3 - 0# greater tensile strength than the staple fiber batt and to require 15-20# greater force to remove a tuft of fiber, as evidenced by the lower tendency of the tow batt to fuzz up under abrasion. Moreover, the tow batt was found to be completely free of the problem of fiber migration and to have superior launderability properties, which greatly enhances its suitability for use as a fabric in the manufacture of blankets, clothing, etc. It is also highly suitable for use in the manufacture of filtration products, shipping blankets, paper machine felts, etc.

EXAMPLE IV A lo6 denier per filament, 40,00'0 total denier dull acetate continuous filament tow was processed on the 'threaded roll" tow opening apparatus previously described in which the first set of rolls were operated at a speed of about 45 meters per minute, and the second set of rolls at about 66 meters per minute. The opened tow band was then spread to a width of 30 cm. by a curved bar spreading device of the type shown in Figs« 1 and lb. The web so formed was found to have a base weight of 18 grams per square meter. A portion of this web was passed at a speed of 45 meters per minute through a chamber containing triacetin mist as a bonding agent. The ultimate bonded web was found to have a base weight of 18 grams per square meter.

EXAMPLE V A second portion of the spread tow web of Example IV was bonded in the same manner but additionally was calendered at a temperature of 225°F. and no pressure other than the contact pressure of the calender rolls. The bonded web was found to have a base weight of 18 grams per square meter. The tow processed as in this example and the preceding one may be advantageously used as backing material, pattern material, industrial carrier webs, sanitary napkin covers, seed bed material, filtration fabrics, reinforcing material for plastic laminates, etc.

EXAMPLE VI A polyester continuous filament tow having a total denier of 225,000 and a denier per filament of 5.0 was opened and spread into a band 100 cms. wide in the same manner as set forth in the preceding examples, with the first pair of rolls of the tow opening apparatus operated at a speed of about 11 meters per minute, and the second pair of rolls at a speed of about 19.4 meters per minute. This web was then cross lapped into a batting having a base weight of 326 grams per square meter and a width of 68.5 cm. The batting was interposed between two sheets of cotton scrim, and thereafter both sides of the "sandwich" structure were sprayed with a bonding agent composed of a water dispersion containing 55% by weight of modified vinyl chloride polymer and 1 part water. Finally the entire laminated structure was dried by being passed twice at a speed of 2*4 meters per minute through an infra-red oven set at 320°F. The finished fabric had a base weight of 738 grams per square meter and a height of 5 cm. at zero compression, and was found to be free of fiber migration and to compare favorably with a corresponding staple fiber "sandwich" in the properties of compressibility, recovery, retention of bulk, etc. It is well suited for use in the manufacture of upholstery stuffing, furnace and air conditioner air filters, sleeping bag insulation, blanket interliners, etc.

EXAMPLE VII An opened and spread polyester continuous filament tow having a total denier of 220,000 and a denier per filament of 5.0 was processed into a linearly lapped web 90 cm. wide. Opening was by means of the "threaded roll" apparatus.

Three portions of this web were plied with the filaments of the middle web oriented transversely to the filaments of the outer webs. This assembly, having a base weight of 94 o 5 grams per square meter was then sandwiched between 2 and secured by sewing a quilted pattern of 12.9 cm. quilts to two plies of woven nylon fabric. The finished structure was possessed of considerable loft, washability and insulating qualities and was found suitable for use in such products as insulated garments, comforters, quilts, bedspreads, etc. , and was free of fiber migration, as well as highly resistant to the removal of tufts of fibers vis-a-vis a corresponding staple fiber structure .

EXAMPLE VIII A cellulose acetate continuous filament tow having a total denier of 50,000 and a denier per filament of 3.2 was processed by the "threaded roll" apparatus into an opened and spread band or web 30 cm. wide in the manner hereinbefore set forth. Two portions of the resulting web were plied together with the filaments in each ply oriented transversely to the filaments in the other ply. The assembly was then passed through a spot bonding apparatus of the type illustrated in Fig. Ha which applied to the filamentary structure discrete and overlapping circular areas of triacetin covering approximately 25% of the total surface area of the fabric structure. The bonded fabric was found to have good strength properties both lengthwise and widthwise and was adapted for use in the production of interliners, surgical dressings, hand towels and diapers. In comparison with hereto fore known spot bonded staple fiber non-woven fabrics, the spot bonded continuous filament non-woven fabric was found to be free of fiber migration and also to compare favorably with the staple fiber fabrics in such textile properties as softness, flexibility, drape and loft„ The production of batts suitable for cushioning is also contemplated by the present invention, particularly for the production of pillows, especially from polyester filamentary material. Such pillows are produceable much more repidly than is possible with conventional processes heretofore employed and are much higher quality and better properties than the conventional polyester staple fiber-filled products. The new pillows of this invention are produced at extremely rapid rate at very low cost, using comparatively inexpensive equipment, e.g. from a single strand of taco, it is possible to easily produce six or more pillows per minute. The pillows produced in accordance with this invention are highly resilient, keep their springiness and plumpness much longer in use and do not tend to felt and shrink either in use or in washing.

EXAMPLE IX The apparatus shown in Pig. 1 is used to open and spread a band of crimped cellulose acetate tow having a total denier of 42,000 and made up of 3 denier continuous filaments of cellulose acetate, said filaments having 8½ crimps per inch. The tow band 63 is drawn from the bale 64 through a banding jet 65 comprising a cylinder 66, having a slit running lengthwise of the cylinder at its highest point, and a curved baffle member 67 parallel to, and spaced 0„25 cm. from, the adjacent surface of said cylinder, so that the tow band 63 passes between said baffle member 67 and said cylinder 66. Air under pressure is supplied to the interior of the cylinder 66 and emerges as a stream from the slit of said cylinder, the slit being cut at an angle such that the air stream has a component in a direction opposing the forward motion of the stream, there being an angle of about 30° between the stream emerging fnom the slit and a plane tangent to the cylinder at the point of emergence , The tow band 63, now about 20 cm. wide, passes around stationary tensioning bars 68, 69 to help smooth and uniformly pretension said band, said bars being adjustably mounted, so that their angle to the horizontal may be varied, to adjust the position of the band on the equipment, such as rolls, with which the band comes into contact downstream of said bars. After leaving the bars 68, 69 the band passes into the nip between a pair of rubber-surfaced rolls 70, 71 driven at a peripheral speed of 13.5 meters per minute and then passes horizontally to the nip between a rubber-surfaced roll 72 and a threaded steel roll 73, driven at a peripheral speed of 19.8 meters per minute, said threaded roll having helical threads of 14 turns per inch cut about 1/16 inch deep into its outer surface. The tow entering the nip between rolls 72, 73 is still about 20 cm. wide. From these rolls it passes still in the same horizontal plane to an air spreader 74 (see also Figs. 15 and 16) having a tow-receiving slot 76 which is 60 cm, wide and 10 cm. long. The tow-receiving slot 76 is defined by an upper wall 77 and a lower wall 78 spaced 0.25 cm. apart.

Below the lower wall 78 is a plenum chamber 79 supplied with air under a constant pressure of 4 psig from a suitable source (not shown) and communicating with the tow-receiving slot 76 through air slits 80, each 0,0175 cm. wide at their outlet ends and tapered to said outlets at an included angle of 45°, said slits being each 2¾5 c¾v long and so arranged (as shown in Pigs. 16 and 17) that the end of one slit is aligned, in the direction of movement of the tow, with the end of the adjacent slit, so that air is supplied to the tow band across the full GQ-em„ width of the slot 76. The slits are arranged at small angles (e.g. about 5°) to the line perpendicular to the direction of movement of the tow with the slits on opposite sides of the median line of the spreader being mirror images, as shown in Pig. 17j it is found that when the slits are all parallel, and at an angle to said perpendicular line, there is a tendency for the tow band to be turned from its straight path by the action of the air, the band at one side of said median line being retarded and at the other side bein accelerated. Instead of angularly arranged slits there may also be employed slits 80a (Pig. 18) running perpendicular to the direction of movement of the tow and in parallel rows, spaced with the end of a slit in one row aligned, in said direction of movement, with the end of a slit in the adjacent row so that the air is supplied to the tow band across the full 60 cm. width of the slot 76, without any substantial operative overlap of the slits.

The tow band diverges uniformly from its 28· cm, width at rolls 72, 73 to the full 60 cm. width at the exit of spreader 7^s the entrance of which is located one foot-from the nip of rolls 72, 73. The tow is pulled through the spreader 7^ by the action of a pair of rolls 81, 82, making an "S-wrap" around these rollsj that is, passing 180° around rubber-surfaced roll 8l then passing through the nip between the rolls and then making another l8o° wrap around a steel- surfaced roll 82. The tow web keeps its 60 cm. width during its travel to and around the rolls 81, 82 which are driven at a peripheral speed of 13.2 meters per minute.

From the lower portion of roll 82 the tow then passes to the entrance of air spreader 83 which is located 0.9 meters horizontally from, and about 0.3 meters below, the level of the bottom of roll 82, so that the tow makes a smooth curve which is horizontal at the entrance of spreader 83. The spreader 83 is of the same design as spreader 7·+, except that its tow-receiving slot is 125 cm. wide, and it is operated under the same air pressure as spreader 74. The tow web spreads uniformly in its horizontal passage to spreader 83, at which it reaches its 125 cm. width and then maintains the same width during its passage to a pair of rolls 84, 85, driven at a peripheral speed of 12.6 meters per minute, which serve to pull the web through the spreader 83. Roll 84 is rubber-surfaced while roll 85 is steel-surfaced; the top of roll 84 is on a level with the tow-receiving slot of spreader 83 and below the bottom of roll 82, The tow makes an S-wrap about the rolls 84, 85, falling from the roll 85 in a freely hanging shallow catenary 86 onto the horizontal moving surface of a wide endless belt 87 driven at a speed of 13,8 meters per minute. An idler roll 88, mounted on lever arms 89 pivoted at 90, extends across the full width of the tow web on belt 87; this idler roll serves to bring the two webs into firm contact with the belt 87, to define the shape and position of the catenary 86, and also to keep any loose ends in the catenary portion from being drawn around the roll 85. The path of the belt is .67 m. below the bottom of roll 85 and the roll 88 is mounted cm. forward (in the direction of movement of the belt) of the center of roll 85. The web on belt 87 has a width of 125 em. and a weight of 5.05 grams per square me er.

In the above example, the upper roll of each of the paris of rolls is pressed downwardly, by any suitable loading device, and is driven by frictional contact with the tow on the lower roll of the pair, which lower roll is rotated by any suitable driving means (not shown) .

EXAMPLE X (a) When the speeds of all rolls and of the belt are increased to about 6 times the values given in Example 9 above (so that the speed of the rolls 84, 85 ic 109 meters per minute) substantially the smae product is obtained.

Surprisingly, despite the great increase the rate at which the web is produced, the total volume of air used and all other conditions, are substantially unchanged. (b) On increasing the speeds of the rolls and the belt to about 10 times the values given in Examnle 9 above (so that the speed of rolls 84, 85 is 182 meters per minute) substantially the same product is obtained, and as in Example 2(a) above, the total volume of air consumed and all other conditions remain substantially the same despite the tenfold increase in productivity.

EXAMPLE XI This example illustrates the use of apparatus which facilitates the handling of the crumpled mass during the cutting and stuffing operations, while the web is fed to the crumpling and folding zone at a high speed. As shown in Pig. 28, the opening and spreading steps are the same as those of Example 9 except that the tow, after leaving the roll 85, passes between a driven roll 139 and an idler roll 140 and drops onto and is permitted to relax on a barrier 141 which, in the embodiment shown in the drawing, is made up of a pair of doors 142, 1 3 pivoted at their upper ends 144, 145 on parallel horizontal pivots 146, 147, respectively. The doors are maintained in closed position, with their edges in contact, in any suitable manner as by means of hydraulic operators 148, 149 which may also be actuated to move the doors to open position. When the desired amount of spread tow has accumulated on the barrier l4l, the doors are opened for a very short interval and the folded and crumpled mass is allowed to drop onto a slowly moving endless belt 150 (moving at a speed of, for example, about IS o 18 sefers per minute) . The doors are then closed again and the tail of tow extending up from the crumpled mass is cut, as by the filament-fusing action of an electrically heated wire 151 moving across this upwardly extending tail. The wire 151 may be mounted, as shown, on one of the doors 143 for movement with that door or may be separately mounted and actuated either independently or by movement of the door. The door actuators may be controlled by a valve 152 actuated by any suitable intermittently operating mechanism 153* preferably one which is responsive to the amount of tow deposited on the barrier l4l; thus the mechanism may be directly responsive to the weight of tow accumulated on the barrier, or it may be operatively connected to one of the feed rolls 139, l4o so that it operates when a given length of tow, as measured by the number of revolutions of these rolls, has been supplied to the barrier, or it may be connected to a suitable timer. The individual masses of tow deposited on the slowly moving belt may be manually or automatically stuffed into a pillow tickings as in the manner shown in Fig. 19 „ It will be seen that, in contrast to Example 99 the stuffing and cutting operations of Example 11 are carried out on a material which is not moving rapidly 9 and the tow may be spread and delivered to the barrier at very high rates such as speeds of about 90 to 180 meters per minute without increasing the difficulty of the cutting and stuffing operations „ The steps of crumpling and of stuffing the crumpled mass into a pillow ticking may be performed substantially simultaneously as by feeding the spread tow directly into the ticking. Thus the spread tow web may be passed down into a guide tube, e„g0 a tube of downwardly tapering conical shape in which the moving tow folds longitudinally and then into the ticking., Here the tow may be crumpled against the bottom of the ticking, which serves as the barrier or an intermediate intermittently movable barrier may be placed just above the ticking „ In the practice of this process, high speed operation is facilitated by omitting devices that produce regular folds 0 The folded and crumpled mass so produced has a random configuration- In this mass the lengths of spread tow between folds may, for example, be in the range of about 2„5 to about 10 cm0 In the finished pillows, the weight of crumpled web material will depend, of course, on the desired resilience and size of pillowo For conventional sizes, e.g. areas of about 3200 to about 3800 sq» cn (a pillow having dimensions of about 50 cm, by 70 cm.) the density of crumpled web is advantageously 8 to 24 kilograms per cubic meter before stuffing into the tick EXAMPLE XII A particularly economical and effective technique and device for the production of pillows from loosely taken up webs is illustrated in Fig, 19 in which the pillow stuffing is formed directly on the moving belt 87 shown in Fig. 14. In this example, a spread web of filament of drawn polyethylene terephthalate 120 cm, wide and weighing 11.8 grams per square meter is produced, in a manner similar to that described in Example 9, from a tow having a total denier of 128,000 and containing 5 denier filaments, said filaments having 5 crimps per cm. The "per cent crimp" in the initial tow is about 60%, "per cent crimp" as used herein being (Ls - 1) x 100 where Lc is the length of Ec any predetermined portion of the tow or web and Ls is the average length of the filaments of said predetermined portion when under a tension just sufficient to remove the crimp. The per cent crimp of the web delivered to the belt 33 is about 38%.

More particularly, the air in the cylinder 66 at 3 psig, the rolls 70, 71 are driven at 18 meters per minute, the rolls 72, 73 are driven at 30.6 meters per minute, the air in the plenum chambers of spreaders 7·+ and 83 is at 3 psig, the rolls 81, 82 are driven at 18.3 meters per minute, and the rolls 84, 85 are driven at 18 meters per minute.

A barrier 91 is placed just above the belt 87, with the bottom of the barrier slidably resting on the belto The lightweight web 92 travelling with the belt piles up in a loosely folded and crumpled mass against the barrier 91 which may, for example, be 25 cm. high. When the desired amount of web (e0g. 5„63 kilograms) has piled up against the barrier, the web is cut transversely upstream of the folded and crumpled mass as with a knife 93, and the mass of folded and crumpled web is pushed or pulled transversely off the belt 87 as by pusher 94 into a suitable hollow form or mold 95 and into a sack-like pillow ticking 96 whose mouth is aligned with the outlet of said mold 95 „ When the freshly cut end of the web travelling with the belt 87 reaches the barrier s a new pile-up is begun and the action is repeated. The whole operation may readily be made automatic, since the web is supplied at a uniform controlled speed and at a uniform weight per unit of time. Thus, in one form of apparatus, the operation of the knife 93 and the pusher 94 are controlled by a suitable timed controller to operate substantially simultaneously at predetermined intervals, so that when a preset weight of the web has folded against the barrier the knife 93 is actuated to cut the web and the pusher is actuated to transfer the accumulated web to the mold 95. In this way highly resilient pillows may be produced continually at a very high rate from siutable stiff, resilient filaments, such as filaments of terephthalate esters.

In another method, the barrier 91 is adapted to be raised when the desired weight of crumpled web has accumulated and the web has been severed, as previously described. The accumulated mass then is carried by the belt 87 to a pillow packing station (not shown) located at the turning point of said belt. The barrier is quickly lowered after the mass of crumpled web has passed under it, so as to begin a new cycle.

The pillows produced from the lightweight webs are superior to those made by filling the pillow with battings formed from polyethylene terephthalate staple fibers. The pillows keep their springiness and plumpness much longer in use and do not tend to felt and shrink either in use or in washing.

EXAMPLE XIII In this example a lightweight web is bonded to a layer of paper on the belt 87. In a manner similar to that described in Example 9, there is formed a spread web of filaments of cellulose acetate 125 cn wide and weighing 5 grants -per square meter from a tow having a total denier of 46, 000 and containing 3 denier filaments, said filaments having 3 crimps per cm. As shown in Figo 20, a web 97 of tissue paper ca rying spaced dots of polyvinyl acetate adhesive, applied with an intaglio roller 98, is fed onto the belt 87 below the tow web 99, and the tow web is pressed against the tissue paper web by the action of the idler roll 88 to bond the v?ebs together, EXAMPLE XIV A web of cellulose acetate containing 240 three denier filaments per cm. of web width, said filaments having 3 crimps per cm. , with the crimps of adjacent filaments being out of registry, said web having a density of 8.4 grams per square meter, is sprayed with 6% of its weight of triacetin, as shown at 100 in Figo 21 of the drawing, and then passed under tension over a driven rotating heated roll 101 maintained at a temperature of 325°F., said roll having spaced square frusto pyramidal projections 102 on its surface (see Fig. 22), there being projections per square cm . , arranged in a pattern of staggered rows. A stable foraminous fabric is produced.

EXAMPLE XV In this example, a plurality of yarns are produced from a single lightweight web. In a manner similar to that described in Example 9, there is produced a web, 125 cm. wide, having a weight of 4 grams per square meter and containing 14,400 three denier filaments of cellulose acetate, there being 3 crimps per cm. in said filaments. From the bottom of roll 85 the web instead of falling in a shallow catenary passes (as shown in Fig. 23) to a slitting zone comprising a roll 103, having circumferential parallel circular V-shaped grooves 104 (Fig. 24) separated by circular sharp parallel ridges 105, and a hot wire arrangement 106 having a series of spaced electrically heated wires 107 having operative portions penetrating said web, there being one such wire 107 for each groove 104 engaged by the web, said wires being aligned with said ridges . The web is drawn through the slitting zone 103 by the action of a pair of rolls 108, 109 about which the slit narrow portions of the web make S-wraps, said rolls being driven at a peripheral speed 5# greater than the peripheral speed of rolls 84, 85. The ridges 105 (and wires 107) are spaced 2 5 cm apart so that the web is slit into portions each of 1368 denier (the measurement in this case being based on the actual, rather than straightened, length of the crimped material) . Prom the roll 109 these portions diverge to eye-gu::: ies 110, spaced further apart, from which they are taken up with a twist of 0,7 turns per cm, an rotating driven bobi¾s 111 mounted in ring spinners 112 of conventional type,, In such ring spinners, as is well known, the fcimdle of filame ts passes through driven feed rolls 113* 11 <, stationary balloon guides 115, and moving travelers ll6, mounted on reciprocating ring rails 117, before passing onto the bobbin 111.

The yarn is very bulky. Its strength is substan-tially that of a continuous filament yam, but it has the appearance of a staple fiber yarn becoase ^f the presence of projecting ends (on the order of about ^ projecting filaments ends per cm0 and loose loops or arches each made up of a small number of crimped filaments (e.g. of one or two filaments) lying along the main body of the yarn. Knitted fabrics of this yarn have an extremely soft, pleasant feel, very suitable for baby sweaters, for example.

EXAMPLE XVI A lightweight web weighing 2.1 grams per square meter is produced, following the procedure set forth in Example 9, using a tow of 20,000 total denier, 5 denier per filament, cellulose acetate.

The following examples illustrate the use of the lightweight webs of this invention for the production of artificial leather. In one particularly simple construction, a batting is produced by cross-laying the lightweight webs, followed by needling the batting to bond the layers together by deflecting portions of the filaments into a path more or less perpendicular to the face of the batting, so that fila- ments lying preponderantly in any one layer have portions deflected into neighboring layers. The needled batting, which may for example be o.08 to 0ο24 ci, thick, is then impregnated with a rubbery material, preferably a synthetic rubber such as a rubbery polyurethane, which may be made from a diisocyanate and a polyester of polyether a polymer of a butadiene 1,3 such as a copolymer of butadiene and another monomer, e.g., acrylonitrile, styrene, vinyl pyridine, methyl methacrylate, or a homopolymer of butadiene or isoprene or chloroprenes or a rubbery ethylene-propylene copolymer, etc. Preferably, the rubbery polymer is deposited in the needled structure in such a fashion that the resulting material remains porus, preferably microporous. This may be done in any known manner, as by the use of blowing or foam- forming agents or by the use of rubber latices followed by coagulation, e.g. with an aqueous solution of an acid such as acetic acid or of a salt as calcium chloride. Advantageously, the rubber is vulcanized as by the inclusion of suitable known cross-linking agents therein, followed by curing. hereafter a thin coating (e.g. 2-8 mils thick), preferably 4 mils thick, of a tough polymer such as polyethyl acrylate, polyvinyl chloride, or a polyurethane or the like, is applied. In a preferred embodiment, that portion of the fibrous backing which is closest to the intended top surface of the leather substitute has a higher concentration of fibrous material. This may be done by the use of shrinkable filamentary material near that surfaces for example, a lightweight web of continuous filaments of shrinkable material may form the top layers of the batting an may, if desired, be needled together with the main portion of the batting followed by shrinking.

EXAMPLE XVII This example illustrates the production of artifical leather, suitable for shoe uppers, using lightweight webs in accordance with this invention.

A lightweight web is produced continuously in accordance with the manner described in Example 9 from crimped drawn continuous filaments of polyethylene terephthalate of three denier per filament; said air spread web having a weight of 14 grams per square met5er. There is also fed to the belt 33 from a source 8l (Pig. 25), a card web of undrawn 5 dpf polyethylene terephthalate fibers having a staple length of 5 cm, The amount of staple fibers is about one-quarter of the weight of the lightweight , eb . The resulting composite is lightly calendered between rolls having a temperature of ~" 250° Co On such calende ing* the surfaces of the undrawn fibers soften and adhere to the drawn continuous filaments of the web. Four cross-laid plies of this bonded composite are then heavily calendered at the same temperature of 250 °C„ to produce a porous structure having a thicV-^ess of about 8-10 mils and weighing 70 grams per square meter , In another operation a lightweight web of drawn polyethylene terephthalate, said web being identical with that described in the preceding paragraph is cross-lapped (Fig. 26) (using a conventional type of cross-.laying operation,, by feeding the lightweight web from the belt 87 onto another belt 119 u ning transversely to the first belt, and reciprocating the web over said belt 119) * the nates at which the belts are operated being adjusted in known manner and the web bel:ng lapped back and forth onto the belt 119, so that 1s produced a batting having a total weight of 525 grains _-er square meter The resulting batting is then passed through a needle punching machine 120 of conventional design in which it is subjected to a series of needles rap-idly reciprocated perpendicularly to the face of the batting so as to bring fibers from one layer of the web into adjacent layers in a direction perpendicular to said face. The batting is passed through the needling zone a number of 'times, and is turned over at each pass, until a total of 15 0 punches per square inch has been made from each side of the batting,, Comparison of this needled batting with a needled batting made from the same weight of the same filaments, but in which the filaments had been cut to staple form and made into r card webs before cross-laying, shows that the needled batting made from the spread webs has a much softer drape and conforms more readily to the shpae of any body on which it is placed.

The calendered composite and the needled batting are brought together in face to face relation and impregnated with a foamable polyurethane-forming composition of known type, such as that disclosed in Tischbein U.S. patent 2,993,813 of July 25, 1961, and then cured, to form a porous rubbery polyurethane in the fibrous structure, and a thin coating of said porous rubbery material above the fibrous structure, the rubbery material also serving to adhere the calendered composite and the needled batt together., The impregnation is controlled to give a product containing about 0# of the polyurethane, based on the total weight. There is then applied, to that side of the impregnated porous product closest to the calendered composite, a thin coating of pigmented polyacrylate of high molecular weight]: this may be done by applying a lacquer comprising polyethyl acrylate in a volatile organic solvent,, or an aqueous dispersion containing of said polymer, followed by drying.

The preferred polyhydro y compound to be used in the formation of the polyurethane is a low molecular weight polymer having hydroxy1 end groups and containing three poly (tet ame h lene ether) blocks per moleculej this low molecular weight polymer may be made by reacting 3 moles of dry poly (tetramethylene ether) glycol having an average molecular weight of about 1000 with two moles of 2,4-tolylene diisocyanate in a manner well known to the art.

EXAMPLE XVIII The lightweight web described in Example 17 is cross-lapped to produce a batting having a weight of 350 graims P^r square meter .

Using the procedure described in Example 9S another lightweight web, of density 14 grams per square yard, is produced from a tow of crimped continuous undrawn polyethylene terephthalate filaments having i> crimps per cm-,0 and a degree of crimp of 30$, This web is then cross-lapped onto the upper surface of the batting described in the preceding paragraph to deposit 140 'additional grams P^r squaremeter. The resulting composite batting is then needled as in Example 17* and then treated to cause the undrawn filaments to shrink, as by boiling in water. The resulting dried batt, which has a relatively dense upper surface, is then impregnated with the foamable polyurethane, cured, and coated, with polyethyl acrylate, all as in Example 17.

In place of the undrawn polyethylene terephthalate filaments, other filamen s which shrink on subsequent treatment may be employed, e.g. undrawn or partially drawn nylon 66 or nylon-6, polyolefines, such as polyethylene, polypropylene, poly-3-methyl butene-1, poly-4-methyl-pentene, etc .

In the production of yarns from lightweight webs, as previously described, the web is preferably of a total denier above 30,000 and the slitting elements are preferably so spaced as to produce strips of less than 10,000 denier, preferably in the range of 500-7000 denier. Other slitting devices besides the hot wires and shearing discs previously mentioned may be employed, e.g. a spaced .series of rotating knives which are pressed against the tow while the latter passes over a hard backing surface such as the circumference of a hard metal-faced roll. The speeds of the shearing discs and the knives at their points of contact with the web are advantageously about the same as the speed of the web. The average fiber length in the yarn will vary depending on the degree to which the web is spread, the degree of entanglement of the tow and the spacing of the slitting elements. Typically the fiber length is at least about one foot and there are substantially no shorter fibers in the yam.

It is within the scope of the invention to air spread the tow at relatively high speeds, such as several hundred feet per minute or more. It has been found that increase in air spreading speed does not result in a proportionate increase in air comsumption.

A modification of the present invention to provide more facile and uniform spreading of an opened tow involves subjecting the opened tow to a sliding contact over an insulating surface in the opening zone. Tows thus treated tend to spread more easily and uniformly with much less tendency to form folds in subsequent processing and are particularly suitable for subsequent spreading. This modification of the present process is illustrate in Pig 27 wherein there is shown a bale 121 of tow made up of crimped filaments such as polyester (e.g., polyethylese terephth-alate) or cellulose acetate. The tow is generally in the form of a relatively flat band, having ridges being formed by the aligned crests and troughs of crimps of adjacent filaments. The band of town is drawn upwardly from the bale 121 over a series of stationary tensioning bars and then through a banding jet 122 which spreads it laterally several fold without effecting any significan registry of the aligned crimps. In the banding jet the tow band passes through a confined zone, between two generally parallel walls 123, 124, where it is subjected across its whole width to one or more streams of air issuing from a slot in wall 123. Prom the banding jet 122 the tow passes under a guide bar 125, t° the nips formed between a drive smooth rubber roll 126 and a grounded threaded steel roll 127. The movement of these rolls pulls the tow under slight tension over the tensioning bars and through the banding jet 122.

Prom the nip of rolls 126, 127 the tow passes to the nip of a second pair of rolls, comprising driven smooth rubber roll 128 and threaded steel roll 129, being deflected in the reach between said rolls by passing under a deflecting guide which may, for example, be a grounded angle bar 130 made of a conducting material such as aluminum extending across the full width of the tow. The tow-contacting edge of the bar 130 is so positioned that the tow is brought into sliding contact with the surface of the rubber roll 128, which is moving faster than the tow as a whole .

In the particular embodiment shown in the drawing, the nip between rolls 126, 127 and the nip between rolls 128, 129 is in a plane tangent to all said rolls, while the straight line joining the tow-engaging edge of the guide bar 130 and the nip of rolls I28, 129 intersects a substantial portion of the roll 129, and the tow slides, relative to the moving surface of roll 128, about 13.6 to l„8 cm before reading said nip.

The rolls 128, 129 are operated at a peripheral speed appreciably greater than that of the upstream rolls 126 and 127. This increase in speed is not sufficient to place the tow under substantial tension; the crimp in the filaments is still noticeabl in the tow passing between the pairs of rolls, and the tow can be manually deflected out of its normal straight path with ease. The higher speed of the downstream rolls 128, 129 is preferably just sufficient to avoid the tendency for slack to develop in the tow, which occurs when all the rolls are operated at the same speed and which, if permitted to continue without correction, may cause the tow to lap around the rolls, interrupting the processing. The downstream rolls 128, 129 may, for example, be operated at a peripheral speed in the range of about 1-1/4 to 1-3/4 times the speed of the upstream rolls 126, 127, preferably in the range of about 1.3 to 1.5 times the upstream roll speed; the exact value for best results will depend on the type of tow and the configuration of the rolls.

After leaving the nip between the rolls 128, 129, the tow passes through air spreader 131 where it is exposed, in a confined zone such as a wide slot to the action of air streams across its whole width, which spreads the tow to a winder and thinner band. The tow is pulled through the spreader 131 by the action of a pair of feed rolls 132 and 1 3, driven at a speed just sufficient to keep the tow passing to said rolls from substantial sagging in its path from rolls 128, 129. The tow passes in an S-configuration about the rolls 132,133, travelling about 180° around the top feed roll 132, which is preferably rubber-surfaced, then through the nip between rolls 132 and 133 and then about l8o° around the lower feed roll 133, which may be a grounded steel-surfaced roD.: From the rolls 132, 133, the tow passes to a second air spreader 134, which is like spreader 131 but wider, where the tow band is spread still further, being forwarded through said spreader 134 by a set of rolls 135, 136. The operation in this stage of spreading is like that in the previous stage, except that the width of the tow band is greater. As shown in Pig. 27, the tow band leaving the lower feed roll 133 makes a shallow catenary in its passage to the banding jet 134, which is mounted with its confined zone 137 horizontal and at a level lower than that of the bottom of feed roll 133. For example, the entranve to the tow passage 137 may be spaced 12 inches below and 36 inches (measured horizontally) beyond the bottom of feed roll 133. In the catenary the tow preferably does not sag below the level of the passage 137.

It is found that when the deflector bar 130 is employed, the filaments in the tow spread apart much more easily, the production of a more uniform spread band of tow is facilitated, and the tow does not tend to form folds in the spreader 131 (which folds may be carried downstream to the next stage resulting in the formation of a non-uniform spread product) „ It is believed that these effects may be due in part to the electrification of portions of the tow band by their sliding contact with the rubber surface of roll 128, despite the contact of portions of said tow band with the grounded conductive surfaced rolls 129 and 133 o It will be observed that these grounded rolls do not make contact with all the filaments of the band at any one time; thus, only the high portions or threads of roll 129 are in pressing contact with varying selected filaments of the tow bando Also, some of the filaments will be insulated from the roll by other filaments in contact with said roll. It wi.l also be observed that the roll 133 engages the same side of the tow as the roll 129.

When the deflector bar 130 is used, the tow shows a tendency to bloom and to become thicker, on leaving the rolls 128, 129, presumably because of electrostatic repulsion of charged filaments. This three-dimensional blooming is controlled and utilized by the movement of the tow through the shallow horizontal confined zone 138 of the spreader 13\ which zone, like the corresponding zone 137 of spreader 134 may, for example, have a depth on the order of about 0.25 cm„ and a length (in the direction of the movement of the tow) of about 10 cm.

The width of the tow band increases uniformly from the nip of rolls 128, 129 to the exit of spreader 131, then remains substantially constant, then increases uniformly from the bottom of roll 133 to the exit of spreader 134 and continues at the same width from the spreader 134 to the roll 135, In accordance with another aspect of this invention, it has been found that the spreading action is enhanced when the tow fed to the patterned roll opening zone carries a hydrophobic silicone finish substantially free of antistatic agents or containing only minor quantities of antistatic agents, e.g. 0.1 t.^ or less. Preferably there is, a tough, flexible, hydr phobic film of silicone resine around each individual fiber.

The silicone 1B desirably applied to the filaments during thei early stages of processing and before the band of tow is crimped. This may be done conveniently by passing the filamen through an aqueous emulsion of a relatively low molecular weight curable liquid silicone prior to the step of crimping the filaments and, in the case of materials which, like polyethylene terephthalate, must be drawn to develop desirable tenacity and resistance to elongation, prior to the drawing operation.

A suitable silicone is readily made, for example, from the hydrolysis of a major portion of an alkyl dichlorohyd rogen silane and a minor portion of a dialkyl dichlorosilane . If desired, there may also be incorporated a small amount of trialkyl chlorosilane (as a chain terminator) and a small amount of alkyltrichlorosilane (to promote preliminary cross-linking). All the alkyl groups are preferably methyl groups. The use of these startin reactants results in a relatively fluid silicone containing a major portion of methylhydrogen-polysiloxane and a minor portion of dimethylpolysiloxane .

The polymeric silicone, after it has been emulsified and the emulsion applied to a filamentary material, can then be catalytically oxidized or cured so that the silane hydrogen are converted to additional siloxane oxygen bridges, to further cross-link the silicone. The resultant cross-linked polymeric product is tough, hydrophobic, and highly lubricating forming a lexible film around the surface of each filam^pt .

It is convenient to first emulsify the silicone so as t form an aqueous emulsion of paste-like consistency. Any of the conventional silicone emulsifying agents, e.g. trimethylnonyl ether, can be used. The average particle size of the silicone polymer in this paste emulsion is generally from about 1 to 8 microns, and typically is about 5 microns. This paste is then incorporated into the finishing bath, along with catalyst. The catalyst compound used to promote further cross-linking of the cllicone is of the conventional type used for silicone curing and generally is an organometallo salt . Generally the metal portion of such catalyst compound is zinc, tin, aluminum, zirconium, or the like. Suitable catalysts Include zinc acetate, aluminum octoate, organic titanates, and mixtures thereof. As stated previously, such catalyst promotes oxidation of the silane hydrogens to produce additional siloxane oxygen linkages and thereby promote further cross-linking of the silicone polymer.

Generally the catalyst is maintained separately from th silicone emulsion until the finishing basth is to be prepared, and desirably is added as the last component to the finishing bath.

Desirably the weight ratio of silicone to metal catalys is from about 8 to 1 to about 1 to 1. A more preferred range i from about to 1 to about 3 to 1. The aqueous composition app to the filaments may contain, for example, 1 to 5$ of the silicone.

The proportion of silicone on the filaments is advantag eously less than 1$, preferably in the range of about 0.2 to 0. based on the weight of the filaments. finish is advantageously carried out in a stuffer may be of the standard stuffing box type in which the tow is forced into a narrow confined zone, thus folding the filaments back and forth on themselves in their passage through said zone. The tow in the crimper may carry a wet film of the aqueous uncured silicone finishing compostion, which may be subsequently cured by heat treatment of the crimped tow while the latter is maintained in a relaxed condition, e.g. at a temperature above 100°C, for example 130-l80°C. Curing of the silicone may also be affected prior to crimping, as by passing the filaments carrying the uncured silicone finish through a heated drawing zone. When the filaments carry a silicone coating containing very little or no antistatic agent, as previously described, the resulting pillows have especially good resiliency. These filaments have very slick surfaces and there is very little friction between filament surfaces, so that the filaments can slide past each other freely. Thus there is little, if any, frictional inter-ference with the inherent resilient recovery properties of the individual filaments. The pillows stuffed with the filaments are also easily washed, and dry rapidly to return to their original highly resilient condition. In conventional polyester staple fiber-filled pillows the staple fibers carry a con-siderable proportion of a relatively tacky antistatic agent which increases the fiber-to-fiber friction and decreases the resiliency of the pillow. The presence of antistatic agent is, however, essential when the staple fibers are employed in order that these fibers may be handled readily in the usual preparatory operations, e.g. picking and carding. A preferred modification of this aspect of the present invention is described ir. the following example „ EXAMPLE XIX A band of tow, having a total denier of 100,000, comprising 5 dpf filaments made of cellulose acetate, having crimps per cm. and carrying 1/1% of a cured silicone coating, was passed through the apparatus shown in Fig0 27 „ In this example, the diameters of all the rolls 126, 127, 128, 129 were 1605 cm», the roll 126 was driven at a peripheral speed of 12» 3 meters per minute, the roll 128 at 17 meters per minute, the roll 133 at 13 meters per minute and the roll 136 at 13,5 meters per minute. The rolls 127, 129, 132 and 135 wer spring-pressed towards the lower rolls 126, 128, 133 and 136 respectively, and were thus driven by contact with the tow moving over said lower rolls „ Rolls 126 and 128 were both surfaced with rubber having a hardness of 70 Durometer, A scale (Carotex B" ) Each of rolls 127 and 129 had opposite helical threads, of 604 turn per cn cut about 0o15 cm„ deep into its outer surface, from the center of each roll to its endo The distance between the nip of rolls 126 and 127 and the nip of rolls 128, 129 was 50 cm. and the deflector was mounted with its tow-engaging edge 1«25 cm* below the straight line joining said nips and cm, upstream of the nip of rolls 128, 129, so that the tow was in contact with the rubber-covered roll 128 over an angle of 23°, equal to a distance of 3.45 cnu before reaching the nip. Taking the speeds of the tow and roll 128 into account, the sliding movement of the tow relative to the rubber surface of said roll extends for lo04 cm, The tow, which is spread to a width of about 20 cm0 at the banding jet 122 is spread to a width of 60 cm0 at the jet 131 and 125 cm ; at the Jet 13 , and may then be rolled or folded on Itself to produce a batting for use in stuffing pillows, upholstery, insulation for clothing, etc.

It will be apparent that the opening of the tow for the purposes of the present invention may be effected by means differing from the "threaded roll" type of apparatus disclosed in the aforesaid earlier application, although this tow opening and crimp deregistering apparatus is preferred due to its high efficiency and its uniformity of operation. For example, the grooves on the roll need not be helical but could have other configurations such as circular rings. If desired, the grooves' may be discontinuous, i.e. take the form of intermittent depressions in the surface of the roll, and may, for example, impart to the roll surface a checkerboard or other pattern of alternately raised and depressed areas. Both rolls of any one set could be grooved, if desired, although best results are achieved when but one roll is so grooved. The path of the tow in moving between the nips of successive roll sets is horizontal in the Dunlap et al disclosure but can be made vertical if desired.

As already mentioned, the spreading of the opened tow may be achieved by other means than one or a plurality of curved bars or by air spreading as described herein, for example, by means of curved rolls and diverging endless belts. Furthermore, other sequences and combinations of the process steps disclosed herein and the selection of differing operating conditions under which the products contemplated by the present invention are produced will readily suggest themselves to those skilled in the art.

Claims (10)

1. 222+83/2 HAYINtt HDS? particularly described and ascertained the n ure^ of or said Invention and in what manner the s me is to ¾e performed* we declare that what we c aia la s 1. A non-woven structure composed of a cohesive web of parallel crimped continuous filaments with the crimps of adjacent filaments out of registry and the crimps of the filaments overlapping adjacent jsald structure / filaments on both sides7¾aving a weight of less than about 35 grams per square meter and a width of at least 39 centimeters .
2. 2. Structure as in claim 1 wherein the web is composed of polyester filaments.
3. 3. Structure as in claim 1 wherein the web is composed of cellulose acetate filaments.
4. 4. Structure as in any of claims 1-3 wherein the weight of the web is less than about 17 grams per square meter.
5. 5. Structure as in any of claims 1-4 wherein the average air space per fil is at least five times the average diameter of the filaments of the tow.
6. 6. Structure as in any of claims 1-4 wherein the average air space per fil is over 10 times the average diameter of the filaments.
7. 7. Structure as in any of claims 1-6 wherein the web of filaments is lapped.
8. 8. Structure as in any of claims 1-6 wherein the web of filaments is pleated or corrugated to form a relatively bulkier body.
9. 9. Structure composed of a multi-ply body, each ply of which is a lapped web as in claim 7.
10. 10. Structure as in any of claims 1-9 wherein the web is dimensionally stabilized by an externally applied 12· structure composed of a cohesive web of parallel crimped continuous filaments as in claim 1 stabilized ) farther characterised by the web being lestefei&ened by lamination thereof with a sheet material* 13· Structure as in claim 12 wherein, when the web is pleated or corrugated) the aneet material is bonded to the web et the apexes of the pleats or corrugations* 11*· Structure as in claim 12 wherein the sheet material is a woven fabric* 15» Structure as in claim 12 wherein the sheet material la a knitted fabric* 1©\· Structure as in claim 2 wherein the sheet material is a non-woven staple fiber web* 1?· Structure as in claim 13 or claim it wherein the sheet material is a ootton scrim fabric* 18* Structure as in claim 3 or claim Ik wherein the sheet material is a abric made o synthetic filaments* 19· Structure as in any of claims 12~i8 wherein the web is sandwiched between two piles of sheet material and secured thereto* 20* Structure as in any of claims 12-18 wherein two webs sandwich a ply of sheet material* 21· An article of wearin apparel at least in part composed of a web as in any of claims 1~20. 22* A batting composed of a multiplicity of webs as in any of claims 1*10· 23· A pillow filled with the batting of claim 22, the batting being a randomly folded and crumpled mass of web* 21»· An artificial leather composed of the batting of claim 22 needled and impregnated with a rubbery material* 23· Yarn produced by longitudinally splitting a fabric as in any of claims 1-0. 22483/2/3 2β. Carpet fabric base or underlay padding composed of the bulked structure of any of claims 1-10. the/ 27. The process of producingfa non-woven structure of claim which consists of subjecting an opened tow of crimped continuous filaments to a spreading treatment to cause the tow to assume the shape of an oriented-filament web of substantial width. 28. Process as in claim 27 wherein spreading is effected by moving the tow through a stream of air. 29. Process as in claim 28 wherein tow is spread until the average air space per fil is at least 5 times the average diameter of the tow filaments. 30. Process as in any of claims 27-29 wherein the opened tow contains about 500 to about 1,000,000 filaments having about 3 to about 80 crimps per inch. 31. Process as in any of claims 27-30 wherein the tow is spread until the weight is less than about 35 grams per square meter. 32. Process as in any of claims 27-31 wherein air-spreading is effected by passing the moving tow in flattened condition in a confined zone between parallel walls while a stream of air is directed at the tow across its full width. 33. Process as in claim 32 wherein the thickness of, of the confined zone is f§» the order of 1/10 inch and the air stream is composed of a plurality of narrow substreams spaced across the width of the tow. 34„, Process as in any of claims 28-33 wherein the tow is spread in at least two separate air spreaders. 35. Process as In claim 34 wherein the tow from one air spreader is brought into firm contact with a surface moving at a controlled rate before the tow enters the subsequent air spreader. 36. Process as in claim 35 wherein the contact is with the nip of a pair of moving rolls. 37» Process as in any of claims 27-36 wherein the tow, after air spreading, is advanced at such rate that it is under low tension insufficient to remove crimp and the tow is then relaxed, without substantial change In width, while moving continuously, by moving the tow in a free shallow catenary whereby the degree of crimp per unit length is increased and striations in the spread tow are removed. 38, A process of producing a non-woven structure substantially as described in the Examplesf 39. non-woven structure whenever produced by the process claimed in claim 38. O, An article of manufacture whenever composed of or incorporating the non-woven structure as claimed in claim 39. IQ , -Aa-appap&tua fon &a¾-¾^¾ftg.--Q¾.t.-.t3¾» p¾ipo»ss.. frlaiaea. -#e£®»dtt<s-©.■ to -aad---a^-i-;kk^^ -dmawj^ags., Baaa this Twentieth day