US 3717150 A
An absorbent fabric, preferably used as a diaper, comprised of an absorbent shrinkable web encased in a warp knitted fabric of relatively non-shrinkable yarn. The fabric is substantially non-stretchable when made, but becomes stretchable after washing and drying. A method of making a stretchable fabric is also disclosed.
Description (Le texte OCR peut contenir des erreurs.)
Hunted States Patent 1 1 1111 3,717,151)
Schwartz 51 Feb. 20, 1973  ABSORBENT STRETCHABLE FABRIC 2,774,127 12/1956 Secrist .,l61/75 x 3,388,028 6/1968 Alexander ..161/156  lnventor. Samuel M. Schwartz, El Paso, Tex. 3386,44] 6/1968 De Merrem 61/156 X  Assignee: Farah Manufacturing Company, 2,768,420 10/1956 Rumofl l/75 X [m E] p Tu 3,405,674 10/1968 CoatesetaL. ....l6l/82X 3,339,549 9/1967 Morse ..66/192 x  Filed: Sept. 9,1970
Primary ExaminerWilliam A. Powell 1. N 7 [211 App 0 0,650 Assistant Examiner-James J. Bell Att0rneyBrumbaugh, Graves, Donohue & Raymond  U.S. C1. ..128/284, 66/192, 161/50,
161/86, 161/88, 161/149, lf6l/l/56  ABSTRACT  lnt.Cl. ..A61 13 16  Field of Search ...128/284, 287; 66/192; 161150 An absorbent fabnc, preferably used as a d1aper, coml6ll86 88 149 156 prised of an absorbent shrinkable web encased in a warp knitted fabric of relatively non-shrinkable yarn.  References Cited The fabric is substantially non-stretchable when made, but becomes stretchable after washing and drying. A UNITED STATES PATENTS method of making a stretchable fabric is also dis- 3,457,738 7/1969 Book etal. ..66/192 closed 174,199 2/1876 Cohn. ..161/86 16 Claims, 8 Drawing Figures 3,382,072 5/1968 Surow1tz... ..161/156 X 2,774,128 12/1956 Secrist ..161/150X PATENTEUFEBZOIUYZ,
SHEET 10F I FIG.
E D U G STITCHING NEEDLE FIG. 3
INVENTOR. SAMUEL M. SCHWARTZ his ATTORNEYS PMENTED FEBE 0 I375 sum 20F2 FIG. 8
INVENTOR SAMUEL M. SCHWARTZ By B .Qnm
M WY his ATTORNEYS ABSORBENT STRETCI-IABLE FABRIC BACKGROUND OF THE INVENTION Stretchable fabrics have been available on the market for a number of years and have been used for diapers. Diapers formed with stretchable fabrics are better fitting, more comfortable, less constricting and relatively free from sagging in comparison to diapers made from non-stretchable fabrics. Stretchable fabrics are available having varying degrees of absorbency and, generally speaking, the more absorbent fabrics have been chosen for diaper construction. Where a single layer of stretchable fabric having a hydrophilic (water-absorbent) character is used, it suffers from the disadvantage found in many non-stretchable diapers, namely, body fluids are retained in contact with the wearers skin, thereby encouraging the development of diaper rash.
Diapers have recently been developed which employ a combination of hydrophilic and hydrophobic (waterrepellent) materials. In some instances, a layer of hydrophobic material is provided on the skin-contacting side of the diaper and a hydrophilic layer on the opposite side, so that fluids are passed through the hydrophobic and into the hydrophilic layer, keeping the wearer relatively dry. Such constructions are disclosed, for example, in U.S. Pat. Nos. 3,180,335, 3,295,526, and 2,905,176.
While multi-layer diapers of the type described above have a number of advantages, they have also developed many problems. For example, in a typical construction where the different layers are bonded or laminated together with adhesives, the bond weakens after several uses and washings, often causing the layers to separate. Where the separation of the layers is complete the diaper becomes useless. If separation is partial, an air pocket forms between the separated layers and prevents fluids from transferring efficiently to the absorbent layer. Further, the resin normally used to bond the layers together is non-porous and hydrophobic and impedes the transfer of fluids from one layer to another.
To compensate for the reduced transferability of fluids in such diapers, some manufacturers have increased the size of the pores in the skin-contacting layer The larger pores, however, have the defect that they allow the fluids to return through the hydrophobic layer and come into contact with the wearers skin.
Due to the fact that the multi-layer diaper constructions are made from multiple layers of different materials with different properties, each layer often shrinks a different amount upon laundering, causing a separation or buckling of the layers. As explained above, separation of the layers may impede transfer of fluids from one layer to another, or make the diaper useless. In addition, buckling may make the diaper uncomfortable to wear.
Additional problems arise with multi-layer diapers in the cutting and processing steps of manufacture. When numerous, loose layers are piled one on top of another, the cutting and sewing processes are difficult, and the results are not uniform. Furthermore, if the fabrics are knitted, the edges of such layers often curl, making the binding process more difficult.
SUMMARY OF THE INVENTION The fabric of the present invention overcomes the aforementioned problems by providing an absorbent shrinkable web of hydrophilic material encased in a warp knitted fabric of relatively non-shrinkable yarn. The yarn is formed into a series of interconnected loop chains which are knitted thrbugh the web in the manner, for example, of a tricot or half-tricot stitch. After the web has been encased in the yarn, the fabric is subjected to heat and moisture, causing the web to undergo substantial shrinking relative to the yarn. As a result, the loop chains of yarn loosen, permitting limited stretching of the fabric.
When used as a diaper, the absorbent shrinkable web is comprised of a layer of shrinkable hydrophilic material and at least one layer of a shrinkable hydrophobic material. A diaper having this structure permits immediate transfer of fluid through the hydrophobic layer and into the hydrophilic layer, tending to keep the wearers skin dry.
The improved fabric constructions of the present invention are easier to manufacture and process than those disclosed in the prior art, are more comfortable to wear, and are less costly to produce. When utilized as a multi-layer diaper, the improved fabric has the additional advantages of minimum differential shrinkage and prevention of layer separation and bonding impediments. Such diaper does not allow fluids to return to the wearers skin and does not contain any irritating or harmful chemicals.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view in cross-section of the fabric of the present invention;
FIG. 2 is a schematic view of a stitching apparatus, shown performing the operation of encasing the absorbent, shrinkable web in a warp knitted fabric;
FIG. 3 is an isometric view in cross-section of a twolayer embodiment of the present invention;
FIG. 4 illustrates a diaper made in accordance with the invention;
FIGS. 5 and 6 show variations in the structure of diapers made in accordance with the present invention;
FIG. 7 is an isometric view in cross-section of a three-layer embodiment of the invention; and
FIG. 8 illustrates a swimsuit garment employing the fabric of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings in detail, FIG. 1 illustrates one embodiment of the fabric of the present invention. A continuous web 10 of a shrinkable hydrophilic material is encased in a warp knitted fabric of relatively non-shrinkable yarn 12 forming fabric 11. The fabric 11 becomes stretchable after it has been subjected to heat and moisture and the web 10 has shrunk significantly more than the yarn 12. A normal laundering cycle provides significant heat and moisture for shrinkage of the web 10.
By a web of a hydrophilic material I mean a web of material that is water-absorbent. By hydrophobic yarn I mean yarn that is water-repellent.
After the web has been encased in the yarn 12, and the fabric has been cut to its required size, but before it has been shrunk for stretchability, the edges of the fabric 11 preferably are covered by a border 13 which is stitched into place by conventional sewing machines (not shown). The border 13 prevents the yarn 12 from unraveling and presents a pleasing and finished appearance to the fabric 11.
The absorbent layer 10 is preferably of rayon but it can be of any absorbent material or fabric, such as cotton, wood pulp, or cellulose. Where rayon is used for the hydrophilic layer 10, it may be preferable to blend with it a portion of another material, for example, polyvinylchloride fibers, in order to give the layer more durability. Upon being subjected to heat, the polyvinylchloride fibers melt and bond together the rayon fibers, holding them in place. A construction whereby the hydrophilic layer 10 contains 85 percent rayon and 15 percent polyvinylchloride fibers has produced a product having excellent durability, although it is to be understood that these percentages of rayon and polyvinylchloride are not critical. Since the reduction of the weight of the rayon content has the tendency to reduce the absorbency of the layer 10, it is preferable to use less than 15 percent polyvinylchloride fibers in the construction. It is also to be understood that fibers of another material having the desired durability properties, for example, polyvinyl acetate, can be used in place of polyvinylchloride.
The material forming the web 10 can be spun or unspun, pressed or unpressed, knitted or unknitted,
woven or unwoven.
The yarn 12 which is used to encase the web 10, can be of any suitable relatively non-shrinkable material and preferably is hydrophobic. Suitable materials include spun or unspun yarns of a polyester, nylon filaments, an acrylic, polypropylene, and the like. Such yarn 12, however, has to have the characteristic that it will not shrink substantially upon being subjected to normal washing and drying cycles, or will not shrink more than 50 percent relative to the shrinkage of the web 10.
The material used for the border 13 can be any suitable material, but preferably it is to be hydrophobic and relatively non-shrinkable. It is understood that the border 13 is not a required feature of the invention and it is possible to prepare a suitable absorbent stretchable fabric 11 without it.
FIG. 2 illustrates the stitching process whereby the web 10 is encased in a warp knitted fabric of yarn 12. The stitching machine shown is a Maliwatt' machine which utilizes the Malimo technique of forming fabric at high speeds. Mali machines and the textilefabrics made therewith are disclosed in U.S. Pat. Nos. 2,890,579, 3,030,786, and 3,279,221. It is to be understood that any equivalent machine, for example, the Arachne machine or another Mali machine, can be utilized for preparing the fabric of the present invention.
In the stitching process, the web 10 is conveyed by a support arrangement to the stitching area of the machine where it is compacted and encased by the stitching yarn 12 to form a firm fabric 21. Either a tricot or half-tricot stitch which form interconnected loop chains of yarn can be used.
In the present invention, seven to 14 stitches per inch are preferred. Fewer stitches per inch increase the fluffiness of the construction but decrease its durability. A greater number of stitches per inch increase the durability of the construction, but decrease its absorbability. Where the stitches are on the order of seven per inch, it is preferable to use a material for the web 10 which has relatively long fibers in order to minimize losses in laundering. For example, a construction having a warp knitted fabric 21 of 7 stitches per inch and a hydrophillic layer 10 comprised of rayon with fibers approximately 3 k inches in length has produced a product with excellent durability After the stitching process has been completed, the fabric 11 is cut to the desired size and a border 13 is sewn around its circumference (as heretofore described). Prior to cutting, the fabric 11 is preferably scoured and dried, and the yarn 12 is heat set, in the manner described later in relation to FIG. 3.
If it is desired to make the linear dimension of the hydrophilic web 10 more stable before stitching, it can be pressed by needle punching. The needle punching substantially reduces the thickness of the web 10. The separate step of pressing is not necessary, however, as the stitching machines will compress the web 10 during the stitching process.
For stretchability, the fabric 11 is subjected to at least one normal washing and drying cycle. In practice the fabric 1 1 will shrink approximately 90 percent of its total shrinkage capability during its first laundering cycle. Experiments have shown that the web 10 will shrink approximately 15-25 percent while the yarn 12 will shrink approximately 5-10 percent. Because the web 10 shrinks more than the yarn 12, the shrinkage of the web 10 contracts the loops 22 (FIG. 1) of yarn 12 causing the loops 22 to become more rounded. When tension is applied to the shrunk fabric 11, the loops 22 flatten to at least their original position allowing the fabric 11 to stretch. When the tension is subsequently released, the loops 22 return to their after-shrinkage rounded condition.
FIG. 3 illustrates an embodiment of the present invention where the fabric 11 is utilized as an improved diaper. A hydrophobic layer 14 is placed in contact with a hydrophilic layer 15 and the two layers 14 and 15 are encased in a warp knitted fabric of hydrophobic yarn 12.
The hydrophilic layer 15 and the hydrophobic yarn 12 are of the same materials and constructions as described above.
The hydrophobic layer 14 can be of any hydrophobic material, such as polyethylene, polypropylene an acrylic, 'nylon, or any polyester, but preferably it is Reemay, a product of DuPont, or a spun polyester yarn. The Reemay material used in this embodiment is comprised of continuous polyester fibers (approximately percent) mixed with a high-shrink biconstituent yarn (approximately 20 percent) and is vibrated from spinerettes and spun and bonded into a thin, easily workable web.
The stitching process whereby the layers 14 and 15 are intimately and permanently bound together is the same as that described above in reference to FIGS. 1 and 2.
The stitching process can be utilized irrespective of whether the materials forming the layers 14 and are spun or unspun, pressed or unpressed, knitted or unknitted, woven or unwoven. For example, an unwoven, unpressed web or bat of rayon can be stitched together with an unspun, unbonded, web or bat of polyester to form the diaper construction.
Although it is possible to construct the present invention using an unspun, unbonded hydrophobic layer 14, it is preferable to use a preformed material, for example, Reemay or a spun polyester yarn, as described above.
Also, although the fabrics used in layers 14 and 15 can be of any knitted or woven construction, the fabrics are preferably made using non-woven fabrics. Non-woven fabrics permit a closer contact between two adjacent layers, thus enhancing the transferability of fluids from one layer to the other.
Besides permanently binding the two layers together, the stitching process also provides the necessary holes in the hydrophobic layer 14 which permit fluids to pass through the layer 14 and into the hydrophilic layer 15. The holes are large enough so that the fluids can be forced through them, by the force imparted to the fluids by the wearer and by the pressure exerted by the body of the wearer against the diaper, and yet small enough so that the fluids cannot return through them by liquid flow.
The above-described embodiment of the invention can be used either as a permanent or a disposable diaper. It may be preferable in a disposable construction, however, to use a material which is less costly than rayon for the hydrophilic layer 15. Such materials can be, for example, cotton, wood pulp, cellulose wadding, felt, and other forms of nonwoven materials.
After the stitching process has been completed, the construction is cut to the desired size and a border 13 of a hydrophobic material is sewn around the circumference of such construction, as described above. In addition to enhancing the appearance of the construction 7 and preventing the yarn 12 from unraveling, the border 13 in the multi-layer diaper construction prevents fluids absorbed in the hydrophilic layer 15 from seeping around the edges of the hydrophobic layer 14 and coming into contact with the wearers skin.
For stretchability, the two-layer embodiment is laundered and the two layers shrunk as described above regarding FIG. 1. For a construction wherein the hydrophilic layer 15 is a rayon web blended with 15 percent polyvinylchloride fibers, the hydrophobic layer 14 is Reemay, and the hydrophobic yarn 12 is polyester, the following shrinkage results were achieved when each of the three items were subjected to boiling water (b 212F) and dried at the same temperature:
Rayon web: 19 percent shrinkage in warp or machine direction; 23 percent shrinkage in the crossmachine direction.
Reemay: 3-5 percent shrinkage.
Polyester Yarn: 8-10 percent shrinkage.
Although the Reemay only shrinks on the order of onequarter of the rayon web 15, the substantial decrease in cross-sectional area of the rayon web 15 within the loops 22 of yarn 12 provides the necessary shrinkage for stretchability.
For the above test, a temperature of 2 l 2F was used because it is the approximate temperature used in the washers and dryers of most commercial laundering services. Typical household washers and dryers use slightly lower temperatures, normally within the range of 200F. j'
Temperatures in excess of 300F should not be used in laundering and shrinking the fabric 11 because these temperatures might cause the polyester yarn 12 to shrink an undesirable amount thereby ruining the stretchability characteristic of the fabric 1 1.
The fabric 11 is preferably laundered after completion but before marketing to wash out any dirt acquired during manufacture, any tinting used for internal identification purposes, and any sizing. This laundering step does not have any significant effect on shrinkage, because the fabric 11 is washed in lukewarm water, mounted on a rigid frame while passing through a drying oven, and dried at a temperature on the order of 200F. The fabric 11 can be bleached or dyed at the same time it is laundered.
Where the yarn 12 is polyester or a similar material, the initial laundering step also has the advantage that it can be utilized to heat-set the yarn 12 and hinder its subsequent shrinkage. After the fabric 11 is washed, but before it enters the drying oven, it preferably is passed through an area where the temperatures are in the range of 250280F, sufficient to heat-set the yarn 12. The fabric 11 is to remain in this area only long enough to set the polyester yarn, the moisture retained in the web 15 prevents it from reaching its shrinkage temperature.
The embodiment shown in FIG. 3 permits instantaneous transfer of fluids through the hydrophobic layer 14 with no back-leakage and provides a comfortable, stretchable diaper. Unlike diapers known in the art, the layers 14 and 15 of this construction cannot separate causing decreased transferability and uncomfortable buckling. Also, it is not necessary to use bonding agents which impede the transferability of known diapers. Furthermore, since the present invention is, in effect, a one-layer construction, problems relating to differential shrinkage, and cutting and sewing of numerous loose layers are eliminated.
FIGS. 4-6 illustrate various embodiments of the present invention.
FIG. 4 illustrates a conventional rectangular shaped fabric 11 with rounded corners and is the preferred shape for the present invention when used as a diaper.
FIG. 5 illustrates a diaper construction of the twolayer embodiment wherein the hydrophilic layer 15 is smaller in surface area than the hydrophobic layer 14. This embodiment permits greater ease of handling and fastening of the diaper around the wearer.
The embodiment shown in FIG. 5 is slightly more difficult to manufacture than any of the other embodiments as it requires accurately spacing separate strips of the hydrophilic material 15 on the support arrangement 20 (FIG. 2). The fabric making machines generally produce a fabric 21 which is much wider than the width of a single diaper, and therefore, numerous strips of the hydrophilic material 15 must be placed on a layer of the hydrophobic material 14 for stitching.
It is also possible for two of the opposite edges 25 and 26 of the diaper construction to be concave to facilitate a better fit on the wearer. Such an embodiment is shown in FIG. 6. The dotted lines 30 and 31 on FIG. illustrate the concave edge feature on a diaper where the hydrophilic layer is smaller in width than the hydrophobic layer 14.
FIG. 7 illustrates another embodiment of the present invention in which a second layer 35 of hydrophobic material is placed in contact with the hydrophilic layer 15, sandwiching the layer 15 between two hydrophobic layers 14 and 35. The second hydrophobic layer 35 can be, for example, another layer of DuPont's Reemay, a layer of plastic similar to the material used in infant rubber pants, or a layer of any other hydrophobic material. When used as a diaper, this three-layer construction eliminates the need for protective pants.
The present invention is not limited to diaper constructions, but can be used in numerous ways and can be employed for making many types of garments. The fabric 11 can be utilized, for example, as an absorbent pad or as a swimsuit.
When used as an absorbent pad, the fabric 11 would preferably be substantially rectangular in shape (similar to FIG. 4). Such pads have uses, for example, as bed pads under people who are unable to control their body functions. If it is desired to transfer fluids away from contact with an object or person, then the two and three-layer embodiments shown in FIGS. 3 and 7, respectively, can be utilized.
When the present invention is used as a fabric for a swimsuit 40, as shown in FIG. 8, preferably the twolayer embodiment (FIG. 3) will be employed. The hydrophobic layer 14 next to the wearers skin will transfer the water away from the wearers skin and into the adjacent hydrophilic layer 15. The hydrophilic layer 15 preferably would contain a greater percentage of polyvinylchloride filaments than in the aforementioned constructions in order to make the layer 15 less absorbent and thus able to transfer the water to its outside surface more readily so that it can be evaporated by the air. This construction would prevent the wearer from experiencing the cooling sensation experienced when one first steps out of a body of water and the water still contained in the swimming garment begins to evaporate drawing heat away from one 5 body.
Whenever the two-layer embodiment (FIG. 3) of the present invention is used as a diaper or a pad, preferably it will be necessary to mark one side of the construction in some manner so that the user will not get confused as to which side to place next to the wearer's skin and which side to place away from the wearer. Such markings can be accomplished, for example, by dyeing or tinting the hydrophilic layer 15, or by marking one side with a permanent, colored line. The inclusion of a few parts per thousand of a colored fiber into the web of the hydrophilic layer 15 would tint such layer. Placing a brush or dye marker (not shown) on the stitching machine (shown in FIG. 2) immediately below the stitching needles so that it comes in contact.
were conducted. The results of these tests are provided in the following table:
5 RELATIVE WETNESS 0F DIAPER SURFACES (Dry Fabric Surface 0) Time Intervals (minutes) After Wetting Fabric The three diapers used in the comparative tests with the present construction were all purchased on the open market. The Three-Layer Disposable Diaper was marketed as Pampers (manufactured by Proctor & Gamble Co.) and was comprised of a pad formed from piles of creped cellulose wadding and a porous, hydrophobic top sheet both layers attached to a back sheet of a waterproof material. This construction is covered by the Duncan et al. patent, U.S. Pat. No. 3,180,335.
The Conventional Cotton Gauze Diaper was a prefolded Curity diaper (manufactured by Kendall), comprised of layers of cotton gauze.
The Diaper with Hydrophobic Yarns" was marketed as Babycare (manufactured by Riegel Textile Corp.) and was comprised of a layer of interwoven hydrophobic and hydrophilic yarns (woven so that hydrophobic fibers predominated the outside surface of such layer) and numerous layers of cotton gauze forming an absorbent pad. This construction is covered by the Holliday et al. patent, U.S. Pat. No. 3,113,570.
The four diapers were laid side by side on a plastic film surface and all were wetted with 50 milliliters of tap water. All of the water was poured on one spot of each diaper and that same spot was used for the subsequent measurements of wetness.
A Crystalab Ionimeter (Model CT-2I) water conductivity indicator was utilized for the fabric wetness tests. This instrument is normally used to test the purity of water by measuring the electrical conductivity of the water and the parts per million of salt in the water. The instrument was modified to measure the wetness of the diaper by extending the electrode contact points by suitable wiring and housing the two ends of the wire in a plastic assembly. The contact points were two brass screwheads, fifteen thirty-seconds of an inch in diameter. The plastic probe containing the two contact points weighed 199 grams and exerted a pressure of 1.27 pounds per square inch on the fabric surfaces. Such pressure is of a magnitude comparable to body pressures exerted on a diaper by a baby.
The figures in the above table were read from the logarithmic arc-type" parts per million scale on the Ionimeter and are an index of the relative wetness of the fabric surface. The dryer the surface, the lower the electrical conductivity and thus the lower the measurement of the parts per million of salt'in the water.
Referring to the above table, the results show that the figures corresponding to the Absorbent Stretchable Fabric were consistently and considerably lower than those of the other three diapers. The surface of the Absorbent Stretchable Fabric was thus substantially dryer at the end of each of the six measured time intervals than those of the others.
The figures in the table are also directly proportional. This means that at the end of minutes, the Three-Layer Disposable Diaper was four times as wet as the Absorbent Stretchable Fabric, the Conventional Cotton Gauze Diaper was 2.5 times as wet as the Absorbent Stretchable Fabric, and the Diaper with Hydrophobic Yarns was 4.5 times as wet as the Absorbent Stretchable Fabric.
1. An absorbent stretchable diaper comprising a layer of a hydrophilic material, at least one layer of a hydrophobic material, and substantially non-shrinkable yarn, the hydrophilic and hydrophobic layers being maintained in contact with each other by a series of interconnected loop chains of the yarn knitted through the layers to encase the layers in a warp knitted fabric of the yarn.
2. An absorbent diaper as defined in claim 1 wherein the fabric has a border therearound to enclose the edges of the fabric.
3. An absorbent diaper as defined in claim 2 wherein the border is a hydrophobic material.
4. An absorbent diaper as defined in claim 1 wherein the yarn is hydrophobic.
5. An absorbent diaper as defined in claim 4 wherein the yarn is nylon.
6. An absorbent diaper as defined in claim 4 wherein the yarn is a polyester.
7. An absorbent diaper as defined in claim 4 wherein the yarn is an acrylic.
8. An absorbent diaper as defined in claim 1 wherein the hydrophilic layer is smaller in surface area than the hydrophobic layer.
9. An absorbent diaper as defined in claim 1 wherein the hydrophobic material is a non-woven fabric.
10. An absorbent diaper as defined in claim 1 wherein the hydrophilic material is a web of rayon.
11. An absorbent diaper as defined in claim 10 wherein the hydrophilic material contains at least 1% polyvinylchloride fibers.
12. An absorbent diaper as defined in claim 1 wherein the hydrophobic material is nylon.
13. An absorbent diaper as defined in claim 1 wherein the hydrophobic material is a polyester.
14. An absorbent diaper as defined in claim 1 wherein the hydrophobic material is an acrylic.
15. An absorbent diaper as defined in claim 1 wherein the hydrophilic layer and the yarn have the characteristics that the hydrophilic layer will shrink at least 10% more than the yarn.
16. An absorbent diaper as defined in claim 1 wherein the diaper is comprised of two layers of a hydrophobic material, the hydrophobic layers being placed on opposite sides of the hydrophilic layer to sandwich the hydrophilic layer therebetween.
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