MXPA00010392A - Apparatus, method and system for air opening of textile tow and opened textile tow web produced thereby. - Google Patents

Abstract

The invention provides an air opening jet for use in a process for making a rectangular structure made from a tow of fibers, such air opening jet including a housing, an air jet for moving the tow through the housing and opening the tow, and an accumulating chamber that includes at least one, and preferably two, perforated plates located in the path of the moving tow, and an air control arrangement for controlling the flow of air so that the moving tow is urged into engagement with the perforated plates to retard movement of the tow and cause it to properly accumulate in the accumulation chamber. The invention also includes methods for using the air opening jet apparatus to produce multi-tow band products, and products produced by such methods.

Description

APPARATUS, METHOD AND SYSTEM FOR AIR OPENING OF TEXTILE STOP AND OPENED TEXTILE STYLE FABRIC PRODUCED BY THEM FIELD OF THE INVENTION This invention relates to systems that can be used to open a fiber tow in such a way that the resulting "open tow" of fibers has a shape useful in the production of absorbent structures, and more particularly with an apparatus and method of air jetting. for its opening, for use in such systems and with the products formed by such systems.

BACKGROUND OF THE INVENTION Many types of filaments, fibers and threads (collectively "fibers") are sold as a "tow" in which a plurality of such fibers are pressed together, optionally with crimping, by methods known to those skilled in the art. to maximize the content of the packaging systems, for example, bullets, by which these tow are sold and delivered to users of tow, before using it, such users generally "open" such a tow, separating the pressed fibers at a greater distance Numerous methods and devices for opening tows are known and described in the art, examples of which include U.S. Patent Nos. 3,282,768, 3,523,053, 3,099,594, 4,522,616, 2,794,480. , 3,032,829, 5,591,297, and 5,203,757, the teachings of which are incorporated by reference in the present invention, While such devices have found utility in various applications, such devices typically produce "open" fasteners. rts "that have a substantially circular cross-section, for example, the tops used for cigarette filters or deposits of writing instruments. However, for other applications a rectangular shape is preferred; for example, absorbent structures that are to be used in personal care products such as diapers, bandages, sanitary napkins and similar absorbent products. For such uses, a shape having a substantially rectangular cross section is preferred. A representative sample of these various types of products is disclosed in U.S. Patent Nos. 4,289. "130, 5,117,235 and 5,928,45-2, Invention Registry No. H1565 and PCT International Publication No. Wo 99/30661.

It is also known to use, in systems of the foregoing types, air jets that open the tow and give it a rectangular shape for use in tobacco filter bars and the like, disclosed in U.S. Patent Nos. 4,468,845 and 4,435,239. One of the significant advantages claimed for these systems is the fact that the opening air jet used in the system is designed to operate at very low air pressures (ie below 3 psi), which is said to be true. which eliminates the need for large capital investment in expensive compression fittings and air pipes normally associated with air-opening or "roughing" systems. This air at low pressure is used to move the tow through the opening air jet, while the tow is opened, and then through a set of pads where the open tow is decelerated and delayed in the pad assembly to obtain the desired density and opening of the tow. This deceleration and retardation of the tow is obtained by an adjustable tension arrangement for hooking the tow, and more particularly by a flat, "bore" non-drilled plate which is mounted on a pivot at one end thereof within the pad assembly. and a relatively complex mechanical arrangement for adjusting the movement of the tension plate mounted on pivot towards and away from the tow to thereby vary the tension force applied to the tow by the tension plate.

SUMMARY OF THE INVENTION According to a first aspect of the present invention, an opening air jet apparatus is provided for use in a system for opening a thin tow, relatively wide of textile filaments held together by curling and forming with the open tow a predetermined shape suitable for use, for example, as an absorbent structure for personal care products. The opening air jet apparatus includes a compartment having an inlet opening for receiving a partially open tow and having a configuration corresponding to the shape of the partially open tow. The compartment also has an exit opening through which the tow leaves the compartment and this outlet opening has a configuration corresponding to the predetermined shape.

A jet of air is formed within the compartment adjacent to its inlet opening to create a venturi that moves the tow through the opening air jet apparatus and also further opens the tow, and a source of compressed air communicates with the vent. e-hole of air to provide carrier air for moving the tow through the opening air jet apparatus.

A forming chamber is provided within the compartment and i downstream of the air jet which includes a cross-sectional area that gradually increases in the direction of the flow of the tow corresponding to the predetermined shape, the air jet is disposed within the compartment to make the tow open fully and substantially fill the forming chamber while moving through it.

A storage chamber is located within the compartment downstream of the forming chamber that is constructed and arranged to allow the open tow to accumulate within the storage chamber and be removed from the compartment at different flow rates through the exit opening of the storage chamber. compartment in the default form. The storage chamber includes at least one perforated plate disposed in the tow path and the carrier air that moves through it to cause the tow to latch onto the perforated plate and to cause at least part of the carrier air to pass through. through the perforated plate.

A control valve is provided to maintain the flow of the carrier air at a level that causes at least the portion of the carrier air to pass through the plate. erforated and push the tow towards the frictional engagement with the perforated plate I with sufficient force to retard the movement of the tow through the accumulator chamber and to cause the tow to accumulate in the accumulator chamber.

In the preferred embodiment of the present invention, the accumulator chamber may include a second perforated plate located in spaced relation to the first perforated plate mentioned above, and the tow moves between the perforated plates and is pushed towards engagement therewith by air carrier that passes through both perforated plates. Finally, in the preferred embodiment of the present invention, the predetermined shape of the outlet opening in the compartment is rectangular.

Another aspect of the present invention provides an apparatus and method by which one or more of the air blast openings of the aforementioned type can be used to open and form with multiple flaps a composite band of multiple flaps of a predetermined shape suitable for use , for example, as an absorbent structure for personal care products. In this type of system, instead of supplying a single tow to the inlet end of an opening air jet apparatus, two separate and distinct tows are supplied to the inlet end of a single air jet of I opening or two separate opening air jets are combined there or downstream there in a band composed of multiple tows.

In this system, a first arrangement is provided for receiving a first tow from a towball having predetermined denier units per filament, which spreads the filaments of the first tow into a first tow band and having an outlet end for unload the first tow band from it with a predetermined width. A second arrangement is provided for receiving a second tow from a second towball having predetermined denier units per filament that are different from the predetermined denier of the first tow, which spreads the filaments of the second tow in a second tow band. and having an outlet end for discharging the second tow band therefrom with a predetermined width. The first and second tow bands are then introduced simultaneously into the inlet end of the opening air jet apparatus and moved therethrough for the opening and forming described above in connection with a single tow. The first and second tow bands can also be introduced into two separate opening air jet apparatuses.

Each of said first and second dispositions may preferably comprise a tow band forming jet to receive the respective first or second tow and spread the tow in the form of a band, and at least one pair, and preferably multiple pairs, of supply rollers disposed between the first and second strip forming jets, respectively, and the opening air jet apparatus or apparatuses.

In a contemplated embodiment of this system, the width of the output end of one of the first or second band-forming arrangements is less than the other, whereby the multi-tow band discharged from the output end of the apparatus or Open air jet apparatus has a tow band that has a wider width than the other. It is preferred that the tow band having a greater width have a denier-r per filament that is less than denier per filament of the other tow band. In addition, the system may include a surfactant applicator located downstream of the opening air jet inlet to apply a surfactant to the tow band having a smaller width, and the system may include a glue agent applicator. located 'upstream of the opening air jet to apply a glue agent to the tow band having a greater width. It is also possible to individually vary the delivery speed of the two tow bands at the entrance of the opening air jet apparatus, and individually control the roughing of the two tow bands.

Agree . with another aspect of the present invention, a novel textile fabric is provided, preferred but not necessarily produced by the apparatus of the system and methodology described above, wherein the fabric basically comprises a first and a second tow having each of multiple continuous textile filaments open in such a way that the filaments no longer correspond to one another. In one embodiment, the filaments of the first and second tows are mixed with each other within at least a portion of the fabric and can, for example, be mixed with one another essentially throughout the fabric or predominantly along the interconnection between the first and the second tow. In an alternative embodiment, the first and second tows are generally laminated with respect to one another within at least a portion of the fabric. The filaments of the first and the second tow may be of different density per filament, which has been found to provide improved performance of the fabric compared to a comparable fabric made of a single tow of the same average denier per filament. Additional components can be incorporated into the fabric, for example, a superabsorbent polymer to improve the liquid acquisition and absorption capabilities of the fabric. It is also contemplated that the filaments of at least one of the first and second tows may comprise a fusible bicomponent fiber for joining the filaments of the first and second tows.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a diagrammatic illustration of a typical tow opening system of the type in which the opening air jet of the present invention can be used.

Figure 2 is a perspective view of a preferred embodiment of the opening air jet of the present invention.

Figure 3 is a side elevation view, partly in section, illustrating the air jet of; opening illustrated in Figure 2.

Figure 4 is a plan view of the opening air jet compartment illustrated in Figure 2.

Figure 5 is an elevation end view illustrating the exit opening of the compartment.

Figure 6 is an elevation view of one of the side plates of the compartment.

Figure 7 is an end view 'in elevation of the inlet opening of the compartment.

Figure 8 is a diagrammatic illustration. of an alternative tow opening system using the "opening air jet apparatus" according to the present invention.

Figure '9 is a diagrammatic cross-sectional illustration, that is to say the width, of a first embodiment of a multi-tow composite fabric product formed by the system illustrated in Figure 8.

Figure 10 is another diagrammatic cross-sectional illustration, similar to Figure 9, of a second embodiment of a multi-tow fabric composite product formed by the system illustrated in Figure 8.

Figure 11 is an exaggerated diagrammatic longitudinal cut illustration taken along lines 11-11 in Figures 9 and 10 illustrating the relationship of the filaments of the multi-tow tissue composite products of Figures 9 and 10.

Figure 12 is a diagrammatic illustration of another alternative tow opening system utilizing an opening air jet apparatus in accordance with the present invention.

Figure 13 is a diagrammatic cross-sectional illustration of a first embodiment of a multi-tow fabric composite product formed by the system illustrated in Figure 1.2 Figure 14 is another diagrammatic cross-sectional illustration of a second embodiment of a multi-tow fabric composite product formed by the system of Figure 12.

Figure 15 is an exaggerated diagrammatic longitudinal cut illustration taken along lines 15-15 in Figures 13 and 14 illustrating the relationship of the filaments in the multi-tow composite products of Figures 13 and 14.

Figure 16 is a diagrammatic illustration of another alternative tow opening system utilizing an opening air jet in accordance with the present invention.

Figure 17 is a cross-sectional diagrammatic illustration of a typical multi-tow fabric composite product formed by the system illustrated in Figure 16.

Figure 18 is an exaggerated diagrammatic longitudinal cut illustration taken along line 18-18 of Figure 17 illustrating the general relationship of the fibers in the multiple tow product of Figure 17.

Figure 19 is a table that collects comparative physical data from single-tow tissue product samples formed by the system illustrated in Figure 1 with the sample of ii composite products of multiple tow tissues formed by the system of the Figure 8 Figure 20 is a table that brings together the results of comparative performance tests of the tissue product samples of Figure 19.

DETAILED DESCRIPTION OF THE INVENTION The term "fiber" as used in the present invention means a filament, fiber or yarn of any material, for example, cellulose acetate and triacetate, polyester, polyamide, polyolefin and similar polymeric substances.

The term "tow" as used in the present invention means a plurality of fibers pressed together, optionally with "ripple" as that term is used and understood in the art, by methods known to those skilled in the art to maximize the content of the packaging systems by means of which those tows are sold and supplied, or to facilitate the transport of such plurality of fibers from one point to another, for example, within a manufacturing location.

The terms "rectangular" and "substantially rectangular" as used in the present invention, are to be interpreted as meaning a structure having a generally rectangular cross section with possible slight defects, eg, rounded corners and a slight curvature or cleft along one side.

The fibers comprising the tow can be made of any natural or synthetic substance, or of mixtures and / or combinations thereof, including polyesters, polyamides, acetate. and cellulose triacetate (collectively, an "acetate" tow), polypropylene oxide, polyethylene sulfide, liquid crystalline polymeric substances with which fibers, polyamides, silk, wool, cotton, rayon, polyolefins, polyacrylates, polymethacrylates can be formed , and similar substances with which fibers can be made. Such fibers may or may not have a "termination" applied to them, according to their application. In general, an external termination is applied to such fibers in order to facilitate transport, although the "internal" terminations, contained in the material used to form the fiber, can also be used and such fibers are included within the scope of the invention. . In addition, the fibers of the tow may be any denier, diameter or other denomination of cross-section or size related to the suitable cross-section for producing tow.

The terms "strip forming jet" and "strip forming air jet" are used to indicate a first tow opening device, which uses air to spread a tow in one direction, perpendicular to the path direction. The "strip forming jet" is different and distinguishable from the "opening jet" or the "opening air jet" also described in the present invention.

While the present invention can have a wide variety of tow opening applications, it has been found to be particularly useful in the opening of a tow made of acetate fibers, polyester fibers, polyolefin fibers and polyamide fibers, and blends. of them. For example, an acetate tow may comprise 2,500 to 25,000 fibers having an individual denier of 1 to 10, preferably 3 to 6. The total denier for the complete tow, which is the assembly of 2,500 to 25,000 fibers, is then 2,500 to 250,000. Acetate tows are generally 10,000 to 20,000 individual denier fibers from 3 to 6, which give rise to a tow that has a total denier of 30,000 to 120,000.

The fibers of the tow should be uniformly or substantially uniformly distributed in the width / cross section of the pack or band of tow. This uniform distribution of fibers is important for the process of opening a tow in a rectangular or substantially rectangular shape, and the more nearly uniform the fiber distribution the easier it is to produce an open rectangular or substantially rectangular tow. The crimped or packaged tow having a variety of widths / cross sections can be used according to the invention, for example, from 25 mm (millimeters) to 75 mm wide, preferably from 40 mm to 60 mm, and from 1 mm to 7 mm in height or thickness, preferably 2 mm to 5 mm, with typical dimensions of 50 mm wide and 3 mir-thick.

As previously mentioned, an external termination may be applied to each fiber of the tow, such termination being in a degree of 0.3% to 5% by weight of the package preferably from 0.5% to 2.0%.

The tows used in the practice of the invention are generally "crimped tow" as this term is used and known to those skilled in the art. The curl is made from 5 to 30 crimps per inch of uncurled tow, preferably 20 to 25 crimps per inch of uncurled tow.

While it is to be understood that the present invention may have applications in a variety of tow opening systems, a typical system in which the present invention finds particular application. it is illustrated diagrammatically in Figure 1. A tow 14 can be fed initially through a conventional set of guides (not shown) to flatten and orient the tow 14. The tow is then fed to a jet formed of band 130 of conventional design The strip-forming jet evenly spreads the tow band in the direction perpendicular to the tow processing direction. Generally, the band-forming air jet 130 used in these preferred embodiments can be any air jet known in the art, for example, as described in US Pat. No. 3,226,773 or in co-pending US Patent Application No. 09 / 219,818, filed December 23, 1998, the teachings of which are incorporated herein by reference. The tow 14 is then fed to a set of pre-tension rollers 40 and pressed between the metal roller 42 and the rubber roller 44 of the tension roller assembly 40 so as to stretch the tow and take out of register and separate the fibers of the bast. Within the set of tension rollers 40, the pressure of the rollers, i.e., the force applied to the tow by the rollers 42 and 44, is from 1 to 25 psi, preferably from 5 to 15 psi. Within the device 40 illustrated in Figure 1, the metal roller is the element 42 (upper roller) and the rubber roller is element 44 (lower roller).

After leaving the assembly 40, the tow is fed into the roller assembly 60 comprising an impeller metal roller 62 and a rubber roller 64, the metal roller 62 has circular grooves or is threaded or is a flat metal roller . During its travel from the assembly 40 to the assembly 60, the tow is stretched, the stretching is achieved by the drag associated with the pinch pressure between the rollers 42 and 44. The pinch pressure between the rollers the assembly 60 is 1 to 40 psi, preferably 20 to 30 psi.

After leaving the assembly 60, the tow 14 is passed through a first optional static removal bar 100 to remove any static charge that may be present on the tow 14 and which may interfere with subsequent operations necessary in the formation of a structure absorbent.

After leaving the assembly 60, the tow is fed to the roller assembly 70 which comprises a driven metal roll 72 and a rubber roll 74, said metal roll 72 has circular grooves or is threaded, or is a flat metal roll . During its travel from the assembly 60 to the assembly 70, the tow is stretched, the stretching is achieved by driving the metal roller 72 at a faster rotational speed than the driven roller 62. The rotational speed 72 is between 20% and 20%. 60% faster than roller 62, preferably between 30% and 50%. Each of the roller assemblies 40, 60 and 70 are conventional and known; they include a provision to apply a pressure on one of the. rollers in the assembly for pushing the two rollers in the assembly until they engage with one another at a predetermined pressure level. These conventional assemblies can apply pneumatic, hydraulic, or electrical pressure, but pneumatic control is preferred. The pinch pressure between the rolls of the assembly 70 is from 1 psi to 40 'psi, preferably from 20 psi to 30 psi.

The tow that leaves the assembly 70 'will be referred to hereinafter as tow 14. The grooves or threads of the roller 64 and. 74 have a design or orientation known to those skilled in the art of the processing or opening of tow. The fibers leaving the assembly 70 are substantially non-coincident with one another or open, suitable for opening more or forming with them a raised rectangular structure.

The substantial mismatch or roughness means that 90% or more, preferably 95% or more, of the fibers constituting the rectangular structure or rectangular tow are separated by a distance greater than the distance between the fibers when the tow 14 was removed from the fiber. the bullet 12 After leaving the assembly 72, the tow 14 is passed through an optional static removal bar 101 to remove any static charge that may be present on the tow 14 and which may interfere with the subsequent operations necessary in the formation of an absorbent structure. .

After the static treatment, the tow 14 is transported to an optional liquid additive assembly 80 which includes a tank containing liquids, a metering pump 84 and liquid dispensing applicators 86 within the assembly 80 to disperse liquids on the tow 14 The liquid dispersion applicators 86 can be spray nozzles, disc applicators, rotating brush applicators, wicking contact rollers and similar devices of conventional designs known to those skilled in the art. The liquids that can be dispersed on the tow 14 include water; hydrophilic liquids such as alcohols, glycols, dimethyl sulfide, ketones, ethers and similar substances; plasticizers such as Fiberset 100 or Fiberset '200 (Henkel Corporation, Cincinnati, Ohio); surfactants; and solutions containing plasticizers, surfactants and similar substances known to those skilled in the art. The liquids or solutions may be applied to one or both sides of the tow 14 as it passes through the assembly 86, and may also be applied in specific designs of multiple liquids to create unique effects for transferring or storing liquids in a composite structure. absorbent in which the rectangular tow 14 is included.

After leaving the opening air jet 240, the tow 14 is supplied to the optional assembly 120 where solid substances, eg, superabsorbent polymers (SAP), glues, adhesives, fragrances,. Wood pulp, deodorants, antimicrobial agents and similar substances can be applied to the tow 14 by equipment such as a power outlet feeder manufactured by Solids Flow, Inc. of Fort Mili, South Carolina. For example, in the preparation of diapers containing SAP, SAPs can be supplied as a powder or suspension vertically downward on the tow 14. The rectangular, open, low density tow band structure, which leaving the air jet 240 allows the solid particles to be distributed within the fiber structure of the tow. The fiber structure with evenly distributed solid particles can be rapidly supplied to a subsequent process in order to achieve the containment of the solid particles. The addition of liquids from the set 80"also improves the containment of solids.

After the addition of solid substances by the assembly 120, the tow 14 is supplied to an optional speed supply assembly 90 comprising, inter alia, a driven roller 92 and a roller 94, either or both having a rubber surface or metal for contact with the tow 14. The driven roller 92 controls the overall operation of the process and the speed of the tow 14 while it is being supplied to another process such as a diaper forming machine or composite products. In general, the driven roller 92 and the driven roller 72 are operated at speeds such that the surface to speed ratio (72/92) is from 1.0: 1.0 to 3.0: 1.0, preferably from 1.8: 1.0 to 2.2: 1.0.

The linear speed of the roller 92 is typically controlled by the linear velocity of a pharmacy process of diapers or absorbent composite products to which the raised rectangular tow structure is being fed.

In the preferred embodiment, the tow 14 is supplied directly to a forming process for diapers or absorbent composite products without using the delivery speed of the assembly 90. In this embodiment, the process for diapers or absorbent composite products acts as a speed control of supply or removed. The structure of tow bands with solids and liquids applied is pinched between rollers or with it a single driven roller is wrapped and pulled out of the air jet 240. Fabrics or other fabrics may be introduced to encapsulate the structure. of fiber solids.

Additional optional static removal bars, elements 102 and 103, can be located between the opening air jet 240 and the liquid adding assembly 80, and then the opening air jet 240. The elimination rods of static 100, 101, 102 and 103 can facilitate the control of the processability of the tow 14 by limiting the static electricity and controlling the shape of the rectangular structure of the tow 14. The additional static elimination bars can be used as desired. require and are recommended when the moisture content of the environment is low. Such additional anti-static bars may not only be located after the assemblies 60, 70 and 80, but also between the assemblies 60 and 40, 40 and 130, and 120 and 90. Preferred embodiments have at least the bars that eliminate the static 100, 101, and 102. The opening air jet 240 of the present invention includes a compartment 242 that is formed, at one of its ends, by an inlet opening 244. As best seen in Figure 7, the inlet opening 244 has a generally rectangular configuration which corresponds in general to the shape of the partially open tow 14 which is received in the compartment 242 also includes an outlet opening 246 which, as best seen in Figure 5, also has a rectangular configuration corresponding to the desired shape of the tow leaving the opening airlock apparatus 240.

An air jet, generally indicated with the reference numeral 248, is formed adjacent the inlet end of the compartment 242, and includes a source of compressed air 250 and a conventional control valve 252 for regulating the flow of compressed air from the source of compressed air 250 to an air manifold, 254 through which the compressed air is supplied to the jet orifices 256 forming a conventional air jet to move the tow 14 through a central passage 258 in the compartment 242 as It will be explained more in detail now. As best seen in Figure 3, the passage 258 has a cross-sectional area that gradually increases in the direction of movement of the tow 14 so as to provide a forming chamber 260 downstream of the air jet 248, and this chamber former 260 also preferably has a generally rectangular configuration corresponding to the rectangular shape of the tow 14.

As the accumulation chamber 262 is located adjacent to the exit opening of the compartment 242 and downstream of the forming chamber 260, and the accumulation chamber 262 has a vertical dimension that is larger than the exit opening 264 of the forming chamber 260 , and is also preferably formed with a rectangular configuration that allows the open tow 14 to pass into the accumulation chamber 262 from the forming chamber 260 to accumulate within the accumulation chamber -262 and finally be removed from the compartment 242 through the exit opening 246 a. different flow rates and in the preferred rectangular shape of the tow 14.

As best seen in Figures 3 and 4, a pair of plates 268, each having a large number of perforations 270 therein, are disposed in the accumulation chamber 262 and in the path of the tow 14 while it is coming out. of the forming chamber 260 and entering the accumulation chamber 262. The plates 268 are fixed in place within the accumulation chamber 262 by a plurality of bolts 272 which hold the plates 268 in fixed positions within the accumulation chamber 262 .

The compartment 242 also includes a pair of side plates 274 that is. extend along both sides of it (see Figure 7) to enclose the sides of the accumulation chamber 262 and the forming chamber 260 and each of the side plates 274 is formed with a plurality of perforations 276 that are generally located in a position where the carrier air leaves the forming chamber 260 and enters the accumulation chamber 262, whereby part of the carrier air can be discharged through the perforations 276.

In the operation of the opening air jet apparatus 240, compressed air from the compressed air source 250 flows into the air jet 248 at a flow rate controlled by the control valve 252, and the air jet formed by the orifices 256 moves the tow 14 through the forming chamber 260. When the tow 14 is moved through the forming chamber 260 by the carrier air, it partially opens and expands the tow 14 so that it gradually increases the cutting area cross section in accordance with the gradually increasing cross-sectional area of the forming chamber 260. When the tow 14 leaves the forming chamber 260 and enters the accumulation chamber 262, it is first opened further to correspond to the vertical distance between the ends of the perforated plates 268 (see Figure 3) and the tow 14 engages the interior surfaces of the perforated plates 2 that are disposed in the path a of the bast 14.

While part of the carrier air can be discharged through the perforations 276 in the side plates 274, a substantial portion of the carrier air moves the tow 14 through the space between the perforated plates 268 and passes out through the perforations 270 in the plates 268. By doing so, the air passing out through the perforations 270 pushes the tow 14 towards the frictional engagement with the opposing inner surfaces of the perforated plates 268, and this engagement with friction creates a brake action on the tow 14 which retards the movement of the tow 14 through the accumulation chamber 262 and causes the tow to densify and accumulate in the accumulation chamber 262 at a higher density than it had in the forming chamber 260, after which the open and now densified tow 14 leaves the accumulation chamber 262 through from the outlet opening 246 at different flow rates. It is important that the tow 14 leaving the outlet opening 246 have a desired and uniform density throughout its generally rectangular shape and the present invention provides a unique and highly desirable method for correctly controlling the density of the outgoing tow 14. More specifically , it is evident that the flow velocity of the carrier air determines the delay or brake action applied to the tow 14 as it passes between the perforated plates 268. If the flow velocity of the carrier air is increased, the carrier air passing out through the perforations 270 of the plates 268 it pushes the tow 14 towards the engagement with the plates 268 with a greater force, and thus increases the delay or brake action that is applied to the tow. 14. Conversely, if the flow velocity of the carrier air is decreased, there is a minor brake action applied to the tow 14.

Consequently, a virtually infinite regulation is obtained in the present invention by the simple resort of operating the valve. control 252 to provide a flow to the carrier air which provides the desired brake action to the tow 14, and thus control density of the tow 14 while leaving the compartment 242.

Although it is appreciated that the actual flow velocity of the carrier air varies from one application to another according to numerous factors, it has been found in the operation of a prototype of the present invention that an air pressure of 40 psi provides a desirable density of the tow 14 composed of 0.004 grams / cm3 that exits through the outlet opening having a width of 20 centimeters and a height of 2.5 centimeters.

Figures 8, 12 and 16 diagrammatically illustrate three alternative tow opening systems utilizing the opening air jet apparatus 240 of the present invention in a single form. More specifically, Figure 8 illustrates a system in. which a plurality of tow bands is fed into the inlet of the air jet opening apparatus 240. In Figure 8, where the individual components that are identical to the components described above in relation to Figure 1, are identified by the same reference numerals, two bands of tow 14A and 14B are illustrated, but it is understood that more than two tow bands may be used, depending on the final product desired.

As best seen in Figure 8, the two tow bands 14A and 14B are each fed from a towball and in a conventional belt forming jet 130A "and 130B, respectively, which are described more fully in the FIG. present invention: After the tow bands 14A and 14B are processed by the belt forming air jets 130A and 130B, both tow bands 14a and 14B are supplied by pinching the pre-tension roller assembly 40 that is formed by the metal roller 42 and a rubber roller 44, all described above in relation to Figure 1. After the combined tow band leaves the set of pre-tension rollers 40, this is fed through the same series of components described in relation to Figure 1.

Figure 9 schematically depicts in cross-section the resultant final product leaving the opening air jet 240 in the system of Figure 8, wherein the strip-forming air jets 130a and 130B are installed to supply the tow bands 14A and 14B with identical widths and in a register superimposed on the precise width one with respect to the other. In advancing the opening air jet 240, the set of pre-tension rollers 40 and the roller assemblies 60, 70 effectively produce a substantial degree of initial mixing of the filaments of the tow bands 14A and 14B after the which the opening air jet 240 effectively causes the individual filaments in the two towbates 14A and 14B to mix substantially complete with one another in a composite fabric wherein the individual filaments of the towbands 14A and 14B are they mix with each other essentially in the full width and in the full thickness of the fabric, as schematically depicted in Figure 9.

However, in the system illustrated in Figure 8, the width of the band of each individual tow band 14A and 14B can be controlled individually by the operation of the belt forming air jets 130A and 130B to vary the width of the belts. bast bands 14A and 14B which are simultaneously supplied to the opening air jet 240 to provide, a single product, an example of which is illustrated in Figure 10. Therefore, the bast bands 14A and 14B may, if You want to be initially fed from the. tow through conventional guide components (not shown) -which flatten and orient the tow bands 14a and 14B in a manner known in the art., and when the tow bands 14A and 14B reach the band forming air jets 130A and 130B, the tow bands are spread in a direction perpendicular to the direction of the tow bands to thereby open the two bands. of tow 14A and 14B within the band-forming jets 130A and 130B. Furthermore, the widths of the tow bands 14A and 14B can be varied by the strip forming air jets 130a and 130B so that the final product supplied from the opening air jet 240 has a particular desired composite tow structure. . As an example of such a composite tow structure, Figure 10 illustrates in cross-section the final product leaving the air stream of opening 240 in the installation of the system of Figure 8 so that the air jet forming band 130a supplies a narrower tow band 14a centered on the superposed relationship with respect to a larger and wider tow band 14B supplied by the belt forming air jet 130B. In a manner similar to that described above, the sets of rollers 40, 60, 70 followed by the opening air jet 240 effectively cause the individual filaments of the tow bands 14A and 14B to mix in a composite fabric where, the central longitudinal region of the fabric has the filaments of the two bast bands 14A and 14B mixed substantially throughout, but the regions of the outer edges of the composite fabric are formed essentially entirely by the filaments of the web wider tow 14B, as shown schematically in Figure 10.

Figure 11 is a schematic representation of a longitudinal cut taken through the tow fabrics composed of Figures 9 or 10 along the cut lines 11-11 which shows the naturalness of the tow filaments and represents. schematically the intimate mixture of the filaments of the tow 14A and 14B, characterized in that the respective filaments of the tow essentially can not be distinguished from one another. Naturally, as recognized by those skilled in the art, many other variations of multi-tow fabric composite products can be produced as a result of the processing system of Figure 8 as well as other possible alternative processing systems of the present invention. , such as those of the Figures 12 and 16 which will be explained in more detail below.

Another alternative processing system using the single-opening air jet 240 is illustrated, in Figure 12, and, again, to the extent that the components illustrated in Fig. 12 are identical to those in Figure 1, are used the same reference numbers and it is not necessary to describe the details here again. In this system, the tow bands 14A and 14B are fed from tow bullets (shown in Figure 8) to the individual belt forming air jets 130 in the same manner described above in relation to Figure 8. Without However, in the system illustrated in Figure 12, the tow bands 14A and 14B are each processed individually through all the components acting on the single tow band 14 in Figure 1, that is through sets of respective respective pre-tensioning rollers 40, and of respective respective roller assemblies 60, 70, and of respective respective liquid additive assemblies 80, and as the two tow bands 14A and 14B are individually processed by a variety of components of shown in Figure 12, this system can be used to effectively control the width of the two tow bands 14A and 14B, and to individually control the delivery and grinding velocity of each tow band 14A, 14B. Additionally, when a liquid additive is individually applied to the tow bands 14A and 14B by the components 80, 84 and 86, which were described in relation to Figure 1 above, different additives or no additives may be applied to either or both of the bands. of tow. 14A and 14B to achieve separate effects for each tow component, for example by varying the enhancement characteristics of the superabsorbent polymer containment, the solids binding, or the liquid distribution of the respective tow bands 14A and 14B. Alternatively or as an aggregate, additives can also be applied to the resulting composite tow fabric downstream of the opening air jet 240. Unlike the system of Figure 8, the use of pre-tension assemblies 40, the roller assemblies 60, 70 and the respective respective liquid additive assemblies 80 for the respective two bast bands 14A and 14B in the system of Figure 12 prevents any mixing of the two tow bands 14A and 14B prior to delivery into the air jet of opening 240. Accordingly, in the composite tow fabric emerging from the opening air jet 240, the individual filaments of the two tow bands 14a and 14B are mixed only through the action of the opening air jet 240 and , therefore, to a lesser extent than in the composite fabric produced by the system of Figure 8. More specifically, the composite bast fabric produced by the system of Figure 12 essentially has three dimensions. is regions of tow identifiably and different in the thickness of the composite fabric: a first region adjacent to an outer face of the composite fabric comprised predominantly of unregistered filaments opened with air from the tow band 14A that essentially melt in a region intermediate centrally in the thickness of the tow fabric comprised of open filaments and without registration of both tow bands 14A and 14B substantially mixed with one another gradually melting into a third region of the opposite outer face of the tow fabric. openings of the bast band 14B. These three regions are schematically represented in the cross section by the composite tow fabrics of Figures 13 and 14, Figure 13 depicts an embodiment of the composite bast fabric produced by the system of Figure 12 where the - 14A caps and 14B have the same width and overlap one another in register in the width and Figure 14 represents an alternative embodiment of the composite tow, similar to Figure 10, similar to Figure 10, where the tow 14A has a narrower width centered on the superposed relation with respect to the wider tow 14B.

Figure 15 schematically represents the three regions of the composite bast fabric of Figures 13 and 14 in the longitudinal section, similar to that of Figure 11. Unlike the composite bast fabric produced by the system of Figure 8. , the space of the composite tow fabric produced by the system of Figure 12 has the respective filaments of the individual tow bands 14A, 14B substantially mixed one with another - predominantly only in the region of the interconnection between the tow bands 14A and 14B when supplied to the opening air jet 140.

It is understood that the ability to use a plurality of individually controlled and / or processed tow bands in combination with the opening air jet 240 offers an opportunity to produce a wide variety of products having a structure and composition that can be adapted to a particular function. For example, it is possible to create a composite tow fabric structure that is particularly well suited to serve as a component of a disposable absorbent device, such as a disposable diaper. A compost structure of an embodiment such as that illustrated in Figures 10 or 14 is suitable for this particular application, and consists of a tow band 14A having higher denier units per filter (DPF), eg. , 6-8 DPF, and a total denier of between 12,000 and 20,000. The tow band 14a is oriented in the middle of the composite structure as illustrated in Figures 10 or 14 so as to be in contact with, ie, closely adjacent to the initial fluid jet region of the disposable absorbent device, and the highest DPF in the tow band 14A provides improved fluid acquisition due to its greater strength and resistance to collapse when hydrated. In a typical example, the strip forming jet 130A of Figure 8, or the strip forming jet 130B applied to the. Step of tow 14A in Figure 12 restricts the width of the tow band 14A to approximately 80 mm. If the system of Figure 12 is used, the liquid applied to the tow band 14a, through the liquid application assembly 80, is a surfactant that improves fluid handling within the fluid acquisition structure. On the other hand, the tow band 14B has a smaller DPF, eg. 2-3, with a total denier of 30,000-40,000, and the tow band 14B is oriented to the bottom of the composite structure so that it is the main main body of the disposable absorbent device. The smaller DPF tow band structure provides improved superabsorbent polymer containment due to the higher density, the greater contact area of the fibers with the surface and a greater number of individual fibers. Thus, for example, a bast band 14B with a total DPF of 2.0 / denier of 40,000 has approximately 20,000 separate fibers, while a bast band 14A with a DPF of 6.0 / total denier of 15,000 has only 2,500 separate fibers. Preferably, the strip-forming jet 130B restricts the width of the tow band 15B to 150 mm, which is the total input width of the opening-air jet 240, so that the tow structure. Compound leaving the tow air jet 240 has a configuration shown schematically in Figure 10. Finally, if the system illustrated 'in Figure 12 is used, the liquid applied to the tow band 14A, through the assembly 80, is preferably a band-forming agent such as a plasticizer, water, or a water-based adhesive. to improve the containment of the superabsorbent polymer and / or the binding or containment of solids within the structure of the tow band 14B.

It is naturally understood that the particular composite tow structures described above are only representative examples of a variety of composite tow structures that can be created using the systems illustrated in Figures 8 and 12. For example, in addition to controlling the width of the Bast bands 14A and 14B, if the system of Figure 12 is used, it is also possible to separately control the supply and / or roughing speed of each individual tow band 14A and 14B by controlling the speed of the roller assemblies 60 and 70 , to vary thus the i | characteristics of the stope bands 14A and 14B that are supplied to the air jet 240. In a similar manner, other filaments may be used to form the bast bands 14A and 14B. 14B. For example, it is contemplated that one of the tow bands may be formed with filaments comprising a bicomponent fissile r material that can be used to join together the filaments of the tow bands 14a and 14B by subjecting the composite tow fabric to a subsequent heat treatment. Naturally, many other alternative embodiments will occur to those skilled in the art.

It is also contemplated that the ability provided by the present invention to selectively combine and mix different tow bands into a composite tow fabric allows the resulting tow fabric to have superior and improved characteristics and / or performance, compared to tow fabrics. from a single band of tow. To evaluate this possibility, experiments were performed comparing a composite tow cloth made in accordance with the system of Figure 8 described above and open tow fabrics were made from a single tow band using the system of Figure 1. The results of such experiments were assembled in the frames of Figures 19 and 20. Each fabric was treated identically to apply to it a layer of a superabsorbent polymer (SAP), appropriate porous and non-porous adhesive layers, and outer coatings of fabrics, to producing from each fabric an absorbent device such as that used in a disposable diaper described above. Two samples were made of separate devices of different composite tow fabrics produced by the system of Figure 8 and three samples of devices made of single-tow fabrics produced by the system of Figure 1, and the devices were then tested to determine its capacities for acquisition and absorption of liquids. The different physical characteristics of the device samples were gathered for comparative purposes in the table in Figure 19, while the results of the testing of such devices were gathered in the box of Figure * 20. Samples of devices made with composite tows using the system of Figure 8 were identified as Samples 6-0601 and 7-0601, while samples of devices made from a single tow using the system of Figure 1 were identified as Samples 2-0601, 3-0601 and 4-0601 ..

As will be seen, device samples made with composite tow fabrics achieved superior acquisition and absorption results compared to devices made with single-ply fabrics, even with single-ply fabrics having the same average denier per filament than composite tow fabrics. It is reasonable to conclude from these experiments, that 'composite tow fabrics provide better containment of the superabsorbent polymer than fabrics made from a single tow, which, in turn, indicates that the structure of the tow has a greater degree of stability.

Another unique system utilizing the opening air jet 240 of the present invention is illustrated in Figure 16 where, again, like reference numbers are used to identify the same components of the system described above in conjunction with Figure 1. this system, each of the tow bands 14A, 14B are separately through a series of processing steps and then fed into the inlet of a separate opening air jet 240. More specifically, as illustrated in Figure 16, each of the two bands 14a and 14B are individually passed through a strip forming jet 130, then through the roller assemblies 40, 60 and 70 described above, and then through the liquid aggregate assembly 80, after which each band is fed at the entrance of a jet of opening a-Ljre 240.

The two bands coming out of the opening air jets 240 are then combined and supplied together to the same components that are downstream of the opening air jet 240 illustrated in Figure 1, and when the combined tow bands are moved to Through the set of speed supply rollers 90, a composite bast fabric is created as illustrated diagrammatically in Figures 17 and 18.

As the tow bands 14a, 14B are opened and processed individually in a separate opening air jet 240 and then combined together, the tow bands 14a, 14B have a generally laminated laminated relationship, shown schematically in Figures 17 and 18, with very little entanglement of the fibers of the two tow bands, 14A and 14B, compared to the multi-tow fabrics illustrated in Figures 9, 10, 13 and 14.

Another advantage of the multi-tow fabrics formed by the system of Figure 16 is that the laminated construction of the fabric makes it suitable for different types of specialty processing. For example, each layer in the product may be provided with separate and individualized terminations at the liquid additive stations 80, and, if desired, one or both liquid additive stations 80, or an additional processing stream downstream of the the opening air jets 240 can insert a desired material (eg, a superabsorbent polymer) between the layers formed by the tow bands 14a and 14B.

Accordingly, persons skilled in the art will understand that the present invention is susceptible of wide utility and application. Many embodiments and adaptations of the present invention in addition to those described in the present invention, as well as many variations, modifications and equivalent arrangements, will be evident or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or the scope of the present invention. Accordingly, while the present invention has been described here in detail with respect to its preferred embodiment, it is to be understood that this disclosure is illustrative and exemplary only of the present invention and is made merely for the purpose of providing a full disclosure of the invention. The preceding disclosure is not intended or to be construed as limiting the present invention or exclusive of any such embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the appended claims and the equivalents of them.

Claims (49)

CLAIMS Having described and determined the nature and scope of the present invention and the manner in which it is to be put into practice, it is hereby declared that what it claims as an invention and exclusive property is:

1. An opening air jet apparatus for use in a system for opening a thin, relatively wide tow of textile filaments held together by crimping and forming the open tow with a predetermined shape suitable for use as an absorbent structure for care products personal, characterized because it comprises: (a) a compartment having an inlet opening for receiving a plurality of partially open tows and having a configuration that generally corresponds to the shape of the partially open tow, and having an outlet opening through which said tow it leaves said compartment and has a configuration that generally corresponds to said predetermined form; (b) an air jet formed within the compartment adjacent said inlet opening thereof to create a venturi that moves the tow through the! opening air jet apparatus that also opens the tow; (c) a source of compressed air communicating with said air jet to provide carrier air for moving said tow through the jet jet apparatus; (d) a forming chamber within the compartment and downstream of the air jet including a cross-sectional area that increases gradually in the direction of flow of the tow corresponding to said predetermined shape, said air jet being disposed within of said compartment to make -the tow open fully and substantially fill said forming chamber while moving through it; (e) an accumulation chamber located within said compartment downstream of said forming chamber which is constructed and arranged to allow said open tow to accumulate within the accumulation chamber and be removed from said compartment at different flow rates through of said outlet opening of the compartment in said predetermined form, said accumulation chamber includes at least one perforated plate disposed in the path of said tow and said carrier air is moved through it- to cause said tow to engage said perforated plate and causing at least part of said carrier air to pass through said perforated plate; and (f) a control valve for maintaining the flow of said carrier air at a level such that said at least said portion of said carrier air passes through said perforated plate and urges said tow to frictional engagement with said plate. perforated with sufficient force to retard the movement of the tow through said accumulation chamber and cause said tow to accumulate in said accumulation chamber.

2. An opening air jet apparatus defined in claim 1, characterized in that said accumulation chamber includes a second perforated plate located in spaced apart relation from at least one perforated plate, and in that said tow moves between said perforated plates and is pushed towards the coupling with them po'r: said carrier air through both perforated plates.

3. An opening air jet apparatus defined in claim 1, characterized in that said shape of said outlet opening in said compartment is rectangular.

4. An opening air jet apparatus. for opening a thin, relatively wide tow of textile filaments and forming the open tow with a predetermined shape, characterized in that it comprises: (a) a compartment having an inlet aperture for receiving a partially open tow and an exhaust opening through the front. which the bast leaves said compartment; (b) an air jet formed within the compartment adjacent said inlet opening itself to create a venturi that moves the tow through the opening air jet apparatus and which also further opens the tow; (c) a source of compressed air communicating with said air jet to provide carrier air for moving said tow through the air jet apparatus; (d) a forming chamber within the compartment and downstream of the air jet that includes a cross-sectional area that gradually increases in the direction of flow of the tow, said air jet being disposed within said compartment to cause the Bast opens substantially completely as it moves through it; (e) 'an accumulation chamber located within said compartment downstream of said forming chamber which is constructed and arranged to allow said open tow to accumulate within the accumulation chamber and be removed from said compartment at different flow velocities than Through said outlet opening of the compartment, said accumulation chamber includes at least one perforated plate disposed in the path of said tow and said carrier air moves therethrough to cause said tow to engage said perforated plate and cause at least part of said carrier air passes through said perforated plate; and (f) a control valve for maintaining the flow of said carrier air at a level such that it causes at least said portion of said carrier air to pass through said perforated plate and urges said tow to frictional engagement with said plate. perforated with sufficient force to retard the movement of the tow through said accumulation chamber - and cause said tow to accumulate in said accumulation chamber at a density greater than that which it has in said forming chamber.

5. A method for opening a thin, relatively wide tow of textile filaments and forming the open tow with a predetermined shape, said method characterized in that it comprises the steps of: (a) creating a carrier air jet to move the tow through one compartment from an entrance opening to an exit opening; (b) moving said tow through said forming chamber within said compartment having a cross-sectional area that increases gradually in the direction (of flow of the tow to partially open the tow; (c) moving the tow toward a chamber forming machine downstream of said forming chamber while said tow is made to engage at least one perforated plate located in the path of said tow and causes at least a portion of said carrying air to flow out through said perforated plate; and - I (d) regulating the flow of said carrier air to cause the carrier air to push the tow towards the bearing hitch with sufficient force to retard the movement of the tow through the accumulation chamber and cause the tow to accumulate within said accumulation chamber at a higher density than that in said forming chamber.

6. A system for forming a band of multiple tow and forming it with a predetermined shape suitable for use as an absorbent structure for personal care products, said system characterized in that it comprises: (a) a first arrangement for receiving a first tow from a bale of tow having predetermined denier units per filament, spreading the filaments of said first tow into a first tow band, and having an outlet end for discharging said first tow band therefrom with a predetermined width; (b) a second arrangement for receiving a second tow from a towball having predetermined denier units per filament that are different from the predetermined denier of said first tow, spreading the filaments of said second tow in a second tow band and it has an outlet end for discharging said second tow band therefrom with a predetermined width; (c) an air jet opening apparatus that includes: (i) a compartment; (ii) an inlet for simultaneously receiving said first and second tow bands as a band of multiple tow where said one bands is disposed on the other band; (iii) an air jet to open said band of multiple tow; and (iv) an outlet end for discharging said band of multiple open tops.

7. A system for forming a multiple tow band defined in claim 6, characterized in that the width of said outlet end of one of said first or second arrangement is smaller than the other, wherein said multiple tow band discharged from said end of The outlet of said air jet opening apparatus has a tow band which has a greater width than the other.

8. A system for forming a multiple tow band defined in claim 7, characterized in that said tow band having the greater width has a different denier per filament of the denier per filament of the other tow band.

9. A. system to form a band of multiple tows defined in. claim 7, characterized in that said tow band having the greater width has one denier per filament which is less than the denier per filament of the other tow band.

10. - A system for forming a multiple tow band defined in claim 7, characterized in that the system includes a surfactant applicator located upstream of the opening air jet inlet to individually apply a surfactant to either or both tow bands.

11. A system for forming a multiple tow band defined in claim 10, characterized in that said surfactant is applied only to said tow band having the smaller width.

12. A system for forming a multiple tow band defined in claim 7, characterized in that the system includes an adhesive agent applicator located upstream of the inlet of said opening air jet to apply an adhesive agent to one or both bands of tow .

13. A system for forming a multi-strand band defined in claim 12, characterized in that said adhesive agent is applied to said tow band having the greater width.

14. A system for forming a defined multiple tow band-in claim 6, characterized in that each of said first and second arrangements comprises a tow-forming jet for receiving the first or second respective tow and spreading the tow, and at minus a pair of supply rollers disposed between said first and second strip forming jets, respectively, and said opening air jet apparatus, and wherein the speed at which said first and second tow bands are supplied thereto. 'air cliorró' opening device can be controlled individually.

15. A system for forming a multiple tow band defined in claim 6, characterized in that said first and second arrangements can be individually controlled to vary the roughing of said first and second tow bands

16. A system for opening a multiple band , tow and form it with a predetermined shape suitable for use as an absorbent structure for personal care products, said system characterized in that it comprises: (a) a first arrangement for receiving a first tow from a tow bullet having denier units by predetermined filament, spreading the filaments of said first tow in a first tow band and having an outlet end for unloading said first tow band therefrom with a predetermined width; (b) a second arrangement for receiving a second tow; tow from a bullet from _ tow that has predetermined denier units per filament that are d according to the predetermined denier of said first tow, spreading the filaments of said second tow in a second tow band, and having an outlet end for unloading said second tow from therewith a predetermined width; and (c) an air jet apparatus including: (i) a compartment having an inlet opening for simultaneously receiving said first and second tops having a configuration that generally corresponds to the shape of the first and second tows and having an exit opening • I through which the first and second tows leave said compartment, such as a multilayer tow having a configuration that generally corresponds to said predetermined shape; (ii) an air jet formed within the compartment adjacent said inlet opening to create a venturi that moves said first and second tows through said opening air jet apparatus and which also opens the first and second tows; (iii) a source of compressed air communicating with the air jet to provide carrier air for moving said first and second tows through said jet apparatus; (iv) a forming chamber within the compartment and upstream of the air jet that includes a cross-sectional area that gradually increases in the direction of flow of the first and second tows corresponding to said predetermined shape, said air jet is arranged inside said compartment to cause said first and second tows to open completely and substantially fill said forming chamber while moving through it; (v) a storage chamber located within said compartment downstream of said forming chamber which is constructed and arranged to allow said first and second open tops to accumulate within the accumulation chamber and to be removed from said compartment at flow rates different through said outlet opening of the compartment in said predetermined formsaid accumulation chamber 'includes at least one perforated plate disposed in the path of said first and second tows and said carrier air moves therethrough to cause said first and second tops to engage said perforated plate and cause the less part of said air_ carrier passes through said perforated plate; Y . . . (vi) a control valve for maintaining the flow of said carrier air at a level such that it causes at least said portion of said carrier air to pass through said perforated plate and urges said first and second tow to the frictional engagement; with said perforated plate with sufficient force to retard the movement of the first and second tows through said accumulation chamber and cause said first and second tops to accumulate in said accumulation chamber.

17. A method for opening a band of multiple tows and forming it with a predetermined shape suitable for use as an absorbent structure for personal care products, said method characterized in that it comprises the steps of: (a) moving a first tow from a bale of tow having predetermined denier units per filament through a first arrangement for spreading the filaments of said first tow in a first tow band, and unloading said first tow band therefrom with a predetermined width; (b) moving a second tow from a tow ball having predetermined denier units per filament that are different from the predetermined denier of said first tow through a second disposition for spreading them. filaments of said second tow towards a second tow band, and i discharging said second tow band therefrom with a predetermined width; and (c) combining said first and second tow bands in a double layer tow at the entrance of an opening air jet apparatus, and passing said double layer tow band through said jet opening apparatus. air to open said double layer tow band and unload said double layer tow band.

18. A method for opening a band of multiple tows and forming it with a predetermined shape defined in. Claim 17, characterized in that. the width of the tow band discharged from one of said first or second arrangements is less than the other, wherein said multilayer tow band discharged from said outlet end -of said air jet opening apparatus has a layer of tow band that is greater than the other.

19. A method for opening a band of multiple tow and forming it with a predetermined shape defined in claim 18, characterized in that said tow band having the greater width has one denier per filament that is smaller than the denier per filament of the filament. another tow band.

20. A method for opening a multi-tow band and forming it with a predetermined shape defined in the. I claim 18, characterized in that a surfactant is applied to said tow band having a smaller width downstream of said air jet opening apparatus.

21. A method for opening a band of multiple tow and forming it with a predetermined shape defined in claim 18, characterized in that an adhesive agent is applied to said tow band; has the greater width downstream of the jet opening apparatus of. air.

22. A method for opening a band of multiple tow and forming it with a predetermined shape suitable for use as an absorbent structure for personal care products, said method characterized in that it comprises the steps of: (a) moving a first tow from a bullet of tow having predetermined denier units per filament through a first arrangement for spreading the filaments of said first tow in a first tow band, and unloading said first tow band therefrom with a predetermined width; (b) moving a second tow from a tow bullet having predetermined denier units per filament that are different from the predetermined denier of said first tow through a second arrangement for spreading the filaments of said second tow toward a second tow band , and discharging said second tow band therefrom with a predetermined width; (c) creating a carrier air jet to move the first and second tow bands through a compartment from an entry opening to an exit opening; (d) moving said first and second tow bands through said forming chamber within said compartment having a cross-sectional area that gradually increases in the flow direction of the first and second tow bands to partially open the first and second tow bands; (e) moving the first and second tow bands to a forming chamber downstream of said forming chamber while making said first and second towing bands engage at least one perforated plate located in the path of said first. and second tow bands and at least a portion of said carrier air is flowed out through said perforated plate; and (e) regulating the flow of said carrier air to cause the carrier air to push the first and second tow bands toward the engagement with friction with sufficient force to retard the movement of the first and second tow bands through the tow. accumulation chamber and causing the first and second tow bands to accumulate within said accumulation chamber at a greater density than that in said forming chamber.

23. A system for forming a band of multiple tows and forming it with a predetermined shape suitable for use as an absorbent structure for products for personal care, said system characterized in that it comprises: II (a) 'a first arrangement for receiving a first tow from a tow ball having predetermined denier units per filament, spreading the filaments of said first tow in a first tow band, and having an outlet end for unloading said first tow band therefrom with a predetermined width; (b) a second arrangement for receiving a second tow from a towball having denier units predetermined by filament that are "different" from the predetermined denier of said first tow, spreading the filaments of said second tow in a second tow a tow band and having an outlet end for unloading said second tow band therefrom with a predetermined width; (c) a first air jet opening apparatus that includes: (i) a compartment; (ii) an inlet for receiving said first tow band from the outlet end of said first strip forming jet; . I (iii) an air jet to open said first tow band; and (iv) an output end for downloading said first open band; (d) a second air jet opening apparatus including:,,? I '•' > • - I! • '' (i) a compartment; (ii) an inlet for receiving said second tow band from the outlet end of said second strip forming jet; (iii) an air jet to open said second tow band; and (iv) an exit end for unloading said second open band; and (e) a downstream arrangement of said first and second air jet opening apparatus - arranged to receive said towbates discharged therefrom and combining said towbands into a band of multiple tow.

24. A system for forming a multi-strand band defined in claim 23, characterized in that the width of said outlet end of one of said first or second arrangement is smaller than the other, wherein said multiple strand band formed at said ends of output of said first and second air jet opening apparatus has a tow band having a greater width than the other.

25. A system for forming a multi-strand band defined in claim 24, characterized in that said band of tows having the greater width has one of? I, per filament that is smaller than the denier per filament of the other band of tow.

26. A system for forming a multiple tow band defined in claim 24, characterized in that said tow band having the greater width has one denier per filament which is less than the denier per filament of the other tow band.

27. A system for forming a multi-strand band i defined in claim 24, characterized in that the system includes a surfactant applicator located upstream of the opening air jet inlet to individually apply a surfactant to one or both of the bands tow.

28. A system for forming a multiple tow band defined in claim 27, characterized in that said surfactant is applied only to said tow band having the smaller width. '•'

29. A system for forming a multi-strand band defined in claim 24, characterized in that the system includes an adhesive agent applicator located upstream of the entrance of said opening air jet to apply an adhesive agent to one or both tow bands. -

30. A system for forming a multiple tow band defined in claim 29, characterized in that said adhesive agent is applied to said tow band having the greater width.

31. A system for forming a multi-strand band defined in claim 23, characterized in that each of said first and second arrangements can be individually controlled to vary the roughing of said first and second tow bands.

32. A method for opening a band of multiple tow and forming it with a predetermined shape suitable for use as an absorbent structure for personal care products, said method characterized in that it comprises the steps of: (a) moving a first tow from a bullet of tow having predetermined denier units per filament through first provision for spreading the filaments of said first tow in a first tow band, and discharging said first tow band therefrom with a predetermined width; '' • •! (b) moving a second tow from a towball having predetermined denier units per filament that are different from the predetermined denier of said first tow through a second arrangement and spreading the filaments of said second tow toward a second tow band , and discharging said second tow band therefrom with a predetermined width; (c) moving said first tow band discharged from said first arrangement into a first opening air jet to open and trim said first tow band, and discharge said first tow band therefrom; (d) moving said second tow band discharged from said second arrangement to a second opening air jet and grinding said second tow band, and discharging said second tow band therefrom; (e) combining said first and second tow bands discharged from said first and second air jets of opening into a composite multi-band of tow.

33. A method for opening a band of multiple tows and forming it with a predetermined shape defined in. claim 32, characterized in that the width of the tow band discharged from, one of said first or second arrangements is less than the other, wherein said multiple tow band has a tow band layer that is greater than the other. .

34. A method for opening a band of multiple tow and forming it with a predetermined shape defined in claim 33, characterized in that said tow band having the greater width has one denier per filament that is smaller than the denier per filament of the other band. tow.

35. A method for opening a band of multiple tows and forming it with a predetermined shape defined in claim 33, characterized in that a surfactant is applied to said tow band having a smaller width.

36. An opening air jet apparatus for use in a U system to open a thin, relatively wide web of continuous filament fibers and form the open web of fibers with a predetermined shape for use as an absorbent structure for personal care products , characterized in that it comprises: (a) a compartment having an inlet opening for receiving a partially open band of fibers and having a configuration generally corresponding to the shape of the partially open fiber web and having an exit opening through which the fiber web leaves said compartment and has a configuration that corresponds in general to said predetermined shape; (b) an air jet formed within the compartment adjacent said inlet opening thereof to create a venturi that moves the fiber web through the opening air jet apparatus and that also further opens the fiber web; (c) a source of compressed air communicating with said air jet to provide carrier air for moving said fiber web through the jet apparatus; (d) a forming chamber within the compartment and downstream of the air jet U including a cross-sectional area that gradually increases in the direction of flow of the fiber web corresponding to said predetermined shape, said air jet being disposed within of said compartment to make the fiber web open fully while moving through it; (e) 'a storage chamber located within said compartment downstream of said forming chamber which is constructed and arranged to allow said open fiber web to accumulate within the accumulation chamber and be removed from said compartment.

37. A product characterized in that it is formed with the defined method - in claim 5.

38. A product characterized in that it is formed with the method defined in claim 17.

39. A product characterized in that it is formed with the method defined in claim 22.

40. A product characterized in that it is formed with the method defined in claim 32.

41. A textile fabric characterized in that it comprises a first tow and a second tow each of multiple continuous textile filaments opened in such a way that the filaments are out of register with respect to each other.

42. A textile fabric according to claim 41, characterized in that the filaments of the first and second tows are mixed with one another within at least a portion of the fabric.

43. A textile fabric according to claim 41, characterized in that said first and second tows are generally laminated with respect to each other within at least a portion of the fabric.

44. A textile fabric according to claim 41, characterized in that the filaments of the first and second tows are of different denier per filament.

45. A textile fabric according to claim 42, characterized in that the filaments of the first and second tow are mixed with one another essentially throughout the fabric.

46. A textile fabric according to claim 42, characterized in that the filaments of the first and second tows are mixed with each other essentially along the interconnection between them.

47. A textile fabric according to claim 41, characterized in that the filaments of one of the first and second tows comprise a fusible bicomponent fiber joining the filaments of the first and second tows.

48. A textile fabric according to claim 41, characterized in that it also comprises a superabsorbent polymer.

49. A textile fabric according to claim 41, characterized in that the first and second tows have different widths.