Layered absorbent structure

The present invention relates to absorbent products - in particular to products of this type which are worn by a user against the body._zand are intended to absorb bodily secretions; „- for example diapers, sanitary napkins, sanitary pads and the like.

These products generally include an absorbent element such as a skate or a. of absorbent material, which can be enveloped by a sheath which is permeable to bodily secretion, at least on the side in contact with the body. Frequently, as is the case with disposable diapers and certain sanitary towels, the side opposite the body is lined with a sheet forming a barrier, for example a sheet of material impermeable to bodily fluids, to protect clothing from 'user. This barrier can form part of the sheath enveloping the absorbent material, or can be placed in this sheath on the side-side away from the body.

Eh general ^ such products have assured their function; main, that is, they absorbed and retained body fluid. A major drawback of these products, however, is that after being worn for a period of time, the product is no longer usable before Va5 <th £ f & froft complete) ^ ______- because the fluid reaches an external surface in contact with the wearer's clothing, or because the surface worn against the body becomes so saturated with fluid that the discomfort resulting therefrom prompts the user to discard the product. ~ ar therefore there is a need for an absorbent product allowing full use of the absorbent material, and now the absorbed fluid away from the external surfaces of the product.

An attempt to resolve this problem is described in the

<img file="LU80952A1_D0001.tif" />

US Patents Nos. 3,017,304 and 3,612,055, in which a skin k * is provided on the side of the product worn away from the body, and is intended to attract liquid from the container placed against the body. Unfortunately this skin by itself has a low retention capacity. fluid and soon becomes saturated and ineffective.

In the USA patent n^Q 4,047,531, a laminated structure comprising layers of juxtaposed relatively hydrophobic and hydrophilic wood pulp, is used to attempt to solve this problem. Unfortunately, the use of relatively hydrophobic material tends to reduce the overall capacity of the absorbent product, and therefore does not lead to a satisfactory solution. The need for an absorbent product capable of absorbing as much or more fluid than conventional products, but which keeps the absorbed fluid outside the external surfaces of the product is therefore not satisfied.

The present invention relates to a product for absorbing a body fluid which is at least as absorbent as conventional products, and also has the property of retaining a greater proportion of the absorbed fluid in an inner layer rather than letting the fluid be retained on or near the • surface of the product. Specifically, the subject of the invention is an improvement to an absorbent product having an absorbent element which comprises several absorbent layers and comprises at least one first layer of cellulose fibers. Adjacent to the first layer, there is a second layer which comprises in mixture of sphagnum and l

finely ground wood pulp by mechanical operation, in a weight ratio of at least 0.35 g of wood pulp per g of sphagnum. Preferably, there is at least 0.4 g of finely ground wood pulp per g of sphagnum. Such a finely mechanically ground wood pulp can be chosen from materials such as crushed wood pulp, refiner wood pulp or thermomechanical wood pulp. The particle size of mechanical wood pulp can be characterized by the Canadian standard Preeness (hereinafter referred to as CSP measured by the method of TAPPI-227). Advantageously, the mechanical wood pulp will have a CSP value of between and 600, and preferably between 60 and 300. The second

3.-

<img file="LU80952A1_D0002.tif" />

diapers can also include long fiber absorbent materials such as chemo wood pulp and / or rayon. Preferably the sphagnum is bleached at a clarity of at least 70, measured in the scale system / ^ Iunter \ Color / C. The second layer has the property of retaining at least twice the weight of fluid absorbed by the first layer, before the product drops.

It is preferable that the absorbent structure defined here comprises at least a third layer of cellulose fiber and that the second layer comprising the sphagnum is sandwiched between the first and the third layer, thus forming an inner layer of the absorbent structure. In this way, because the structure thus defined has the unique property of preferentially retaining the fluid absorbed in the second layer, the fluid is kept away from the outside of the absorbent element, and consequently to the away from its exterior surfaces. Surprisingly, this is achieved by the use of a material, sphagnum, which does not in itself have a fluid absorption capacity greater than that of / ordinary wood pulp, which is economical, and yet uniquely ensures the desired result.

In one embodiment, the absorbent member of the present invention is incorporated into a sanitary napkin which also has a permeable, non-woven sheath, and optionally an impermeable barrier sheet. The unique preferential retention of the second layer, compared to the first and the third layer, keeps the two surfaces in contact with the body and in contact with the clothing relatively dry ^ and adds to the comfort of the user and the life of the product .

In a second embodiment, the absorbent element is incorporated in a hygienic tampon in which the unique structure of the element, ensuring the preferential retention mentioned above, allows the tampon to be pulled from the center towards 1¹ outside,

<img file="LU80952A1_D0003.tif" />

/

4.Increasing the duration of effective use of the buffer and reducing the tendency to drop by leaking at the periphery of an externally saturated buffer.

In another embodiment, the element is incorporated into a disposable layer, where again the preferential retention property maintains both the surfaces of the product in contact with the body and in contact with the drier garment, which increases the product life.

The description which will follow with reference to the appended drawings, given by way of nonlimiting example, will make it clear how the invention can be implemented, the features which emerge both from the drawing and from the text of course forming part of said invention.

On the drawings

Figure 1 is a perspective view of a period towel comprising the absorbent structure of the present invention, with parts a-rracKées to reveal the interior structure;

FIG. 2 is a sectional view of the towel of FIG. 1, taken along line 2-2,

FIG. 3 is a perspective view of a second embodiment of a periodic towel comprising the structure of the invention, with parts cut away so as to allow the interior structure to be seen,

FIG. 4 is a cross-sectional view of the towel of FIG. 3, taken along the line 4-4,

I

FIG. 5 is a plan view of a disposable diaper comprising the structure of the invention, with parts cut away so as to reveal the internal structure,

Figure 6 is a sectional view of the layer of Figure 5, taken along line 6-f, / Figure 7 is a perspective view of the structure of the invention, partially wound to form a blank of buffer,

5. FIG. 8 is a perspective view of a tampon produced from the blank of FIG. 7,

FIG. 9 is a perspective view of a structure according to the invention, partially folded to form a tampon blank, and

FIG. 10 is a perspective view of a tampon produced from the blank of FIG. 9.

Referring to the drawings, Figures 1 and 2 show in perspective and in section respectively, a periodic towel comprising as an absorbent element the structure according to the invention. The towel 10 comprises an absorbent element 12 enveloped by a fluid-permeable sheath 14, which may be of any woven or non-woven material permeable to bodily fluids reaching / its surface, such envelopes being well known in the art. A barrier layer 16 impermeable to the fluid is provided on the side of the towel which is to be worn against the garment, opposite the body and is sandwiched between the sheath 14 and the element 12. The barrier layer prevents the fluid from passing over an undergarment and can be made of any thin, flexible material relatively impermeable to the body fluid, for example a polymer film such as polyethylene, polypropylene, cellophane or a material usually permeable to fluid that has been treated to be waterproof, such as hydrophobic impregnated paper. The towel shown is of the type to be placed in the user's undergarment by means of an adhesive. For this purpose, the side facing the undergarment is lined with a longitudinal element in self-adhesive product 18. A protective strip 20 is provided covering the adhesive element 18, to protect the adhesive before use.

According to the present invention, the absorbent element 12 consists of several absorbent layers. A first layer

6.22 includes cellulosic fibers, and may for example include a non-compact set of wood pulp fibers, regenerated cellulose, cotton fibers or chemically or physically modified cellulose fibers such as alkyl carboxylated cellulose, cellulose grej-Lëe or the like. Alternatively, the first layer may be formed by a better ordered cellulose fiber structure, such as stuffing of cellulose sheets or other fiber structures. Adjacent to this first layer 22, and side by side against it ^ is disposed a second layer 24 which is described in another patent application of the applicant, filed simultaneously with the present application. This second layer 24 comprises, in a mixture of sphagnum and finely mechanically ground wood pulp, in a weight ratio of at least 0.35 g of mechanically ground wood pulp per gram of sphagnum. Preferably, there is at least 0.4 g of finely mechanically ground wood pulp per g of sphagnum. This wood pulp can be chosen from materials comprising crushed wood pulp, refiner wood pulp, or thermomechanical wood pulp. The crushed wood pulp consists essentially of trees and branches which have been debarked, cleaned and then ground into particles. Refiner wood pulp: differs from crushed wood pulp only in that the grinding step uses a refiner, i.e. a device similar to a disc_zwell known in the art, generally having metal ribs on its periphery which contact the wood particles and help to separate the wood fibers without damaging them excessively. Thermomechanical wood pulp is analogous to refiner pulp with the difference that the wood particles are heated when they are in the refiner, usually with steam, and this heating con_f tribe to separate the wood fibers. The common characteristic of these so-called mechanical pulps is that no test has been done for j

separating the fibers by chemical means, although they may subsequently after being reduced to the state of fine particles, be subjected to chemical treatments, for example bleaching.

The particle size of mechanical wood pulp 'can be characterized by the Canadian standard Preeness (hereinafter referred to as CSP, measured by the TAITI method T-227) · Advantageously, mechanical wood pulp will have a CSP value of between 3θ and 600, and preferably between 60 and 3θ0 · second layer can also include absorbent materials with longer fibers, such as chemical wood pulp, and / or rayon. Preferably, the sphagnum moss is whitened to a clarity of at least about 70, measured in the Hunter color scale system "0".

Preferably the sphagnum is distributed uniformly in the second layer and has been bleached or otherwise treated to have the indicated degree of color. Da sphagnum having this degree of color can be easily obtained by treating it according to the process for bleaching sphagnum which has been described in US patent application no. 879,833, which is incorporated in the present application for reference. the raw sphagnum of this process is of the Sphagnum type and retains at least 15 times and preferably at least 20 times its weight of water. The sphagnum is passed through a sieve comprising between 10 and 100 mail3.es, and the material that remains on the 10-mesh sieve, mainly • roots and branches is discarded. Also, the material which passes through the 100 mesh screen, namely the fine particles which add little to the absorbent properties and are very difficult to bleach, is also thrown away. 3? Thereafter, the dimensions of the raw sphagnum particles are between 0.15 w (100 meshes) and 1.8 mm (10 meshes), the sphagnum is bleached by a treatment with chlorine and calcium in the form of limestone . De bienobi ment can be done batchwise in a container. Sphagnum is diluted in water to a concentration of about 2% by weight, treated with chlorine, followed by &lt;7

<img file="LU80952A1_D0004.tif" />

a treatment with calcium carbonate, then acid washes and washes with water to give the desired degree of whiteness.

Preferably, the finely mechanically ground wood pulp component of the second layer, and optionally the long fiber absorbent material such as rayon and / or chemical pulp (e.g. kraft or sulfate pulp) are added to the bleached sphagnum still wet and the mixture is kneaded and molded into a plate. .

The plate is then dried and crushed to form the second absorbent layer.

The constituents of this second layer can be assembled in a non-compact manner if one proceeds by means well known in the art to form absorbent pads. It has been discovered, as described in the other mentioned patent application, that the presence of finely mechanically molded wood pulp gives the second layer significant integrity. In addition, the constituents i / can be stabilized by the use of a binder so that the layer still has superior structural integrity. As can be seen in the example shown in the drawings, there is provided a third layer 26 made of the same material as the first layer.

It has been discovered that the towel of Figures 1 and 2, according to the present invention has surprising properties of preferential retention before becoming fully saturated. In other words, it has been discovered that the bodily fluid reaching the surface in contact with the body of the towel, does not remain on this surface and does not distribute itself uniformly in the absorbent element 12. On the contrary, a disproportionate amount of body fluid is retained in the second layer of the structure.

Preferably, this layer 24 retains at least twice the weight of fluid absorbed by any other layer, ie layer 22 or layer 26. In addition, preferably this • z layer retains at least 2 , 5 times more. This result is obtained whether the relative weight of the second layer according to the invention is or is not greater than or equal to the weight of the first layer. This is particularly surprising because, for example, where a layer of wood pulp is used as the first layer and a layer comprising by weight $ 30 of bleached sphagnum sphagnum, $ 38 of ground wood, $ 8 of pulp kraft wood and $ 24 of rayon fiber, the saturation water retention of each of these layers, when measured separately, is essentially the same. Despite this, when the layers are combined in the laminated structure according to the invention, preferential retention is achieved.

Although the preferential retention manifests itself with a great diversity of relative weights of the first and second layers of the structure according to the invention, it is preferable that the weight of the first layer is approximately 0.1 to 2 times the weight of the second layer, and preferably about 0.5 to 1 times this weight. If this ratio is too low, the protective effect of the first layer will be disadvantageously reduced. On the other hand, if this ratio is too large, the preferential retention effect will be reduced to an insignificant point, because the second layer will soon be saturated.

Referring now to Figures 3 and 4, which show another form of sanitary napkin 28 comprising the structure of the present invention. As in the embodiment described above, the towel 28 comprises an absorbent element 30 enveloped by a woven or non-woven sheath 32 permeable to the fluid. Sandwiched between the sheath 23 and the element 30, a barrier layer is arranged. 34 impermeable to fluid to protect the wearer's clothing. the barrier layer 34 covers the major part of the surface of the absorbent element 3θ with regard to the garment, as well as the sides and the extreme longitudinal parts of the major part of the surface of the element 30 opposite the corns. Da towel 28 shown / ·· V felt is provided for an adhesive attachment to the fork of the wearer's clothing and is therefore provided on most of the surface facing the clothing of a self-adhesive element 36 applicable by pressure, protected by a removable protective strip 38.

As in the embodiment described above, the absorbent element consists of a first, a second and a third layer 40, 42, 44 arranged one against the other. However, in the towel 28 of this example, the first and third layers 40, 44 are formed by a sheet of generally rectangular shape made of chipboard fiber, folded in a C shape by folding down the adjacent parts of the two longitudinal edges. towards each other, so that they press against each other and cover the central part of the sheet, the second layer of this example comprises a mixture of sphagnum and mechanically ground wood pulp in the proportions indicated with respect to the first example described, these constituents being agglomerated to form a second layer 42 having dimensional stability. (The second layer is sandwiched between the first and third layers 40, 44 respectively. Here again, this structure has the preferential retention described above.

Reference is now made to FIGS. 5 and 6 of the drawings which represent a disposable layer 46, comprising the structure according to the invention, the layer comprises an impermeable base sheet 48 which preferably is also a film, and a top sheet 50 permeable which may be a nonwoven fabric, a fabric of assembled yarns, a permeable film or the like. In the embodiment shown, the top and the bottom have the same dimensions and are fixed together by their edges. Placed between the top and the bottom is arranged an absorbent element 52 according to the present invention, the absorbent element 52 is smaller than the top and the bottom and is set back from their edges, the absorbent element comprises a first layer 54

<img file="LU80952A1_D0005.tif" />

11.placed against top 50, and containing long-fiber wood pulp. A second layer 56 is provided, which contains sphagnum and mechanically ground wood pulp in accordance with the present invention, under the conditions set out for the second layer in FIG. 1. The opposite lateral edges of the layer are furnished with legs 58 in adhesive tape, to fix the layer around the user. When used, this structure has the preferential retention property described above and tends to keep the absorbed liquid away from the top layer.

Reference is now made to FIGS. 7 and 8 which respectively represent a blank 60 of a tampon and a finished tampon 62 according to the present invention. The tampon blank comprises a first layer 66 of generally rectangular shape having a structure according to the invention, consisting of a tampon of wood pulp fiber. On this first layer 66 is disposed a second layer 64 consisting of a mixture of sphagnum and mechanically ground wood pulp as described above. The blank is brought into the shape of a cylinder by rolling it from one end to the other in a direction parallel to the longitudinal sides of the composite layers. The rolled blank then presents from the outside to the inside in radial straight sections, an alternating succession of firstx ^ t of second layers of the materials. This blank is then compressed in a mold to the shape of the desired buffer 62, as shown in FIG. 8. The tampon 62 is provided with the usual withdrawal string 68 which can be sewn to the withdrawal end of the tampon, or applied by other movens known in the art, such as by forming a loop or a link around the structure rectangular of the invention before its winding.

Figures 9 and 10 show another embodiment of a hygienic tampon according to the invention. A rectangular pad 70 in wood pulp is placed on a sheath 72 of non-woven porous cellulosic fabric, to constitute the first and third layers of the structure according to the invention. On this pad 70 is placed a layer 74 of an absorbent mixture of sphagnum and mechanically ground wood pulp, yes constitutes the second layer according to the invention. The pad 70 with the non-woven sheath 72 is then folded along its longitudinal axis and folded once again to make a U-shaped blank, as shown in Figure 9. The blank is then placed in a cylindrical mold and compressed Radially and / or longitudinally to give it the desired shape of the pad 76 as shown in FIG. 10. An extraction string 78 is provided at the extraction end of the compressed tampon 76 ^ and can be attached in the same way as described above, for example sewn, by means of a loop or engaged in the tampon 70 before β fold, etc .... The finished pad 76 then comprises internal layers or layers of absorbent material containing sphagnum, juxtaposed against layers of wood pulp. In use, due to the preferential retention properties of this structure, the outer layer 70 will retain proportionally less fluid than the inner layer 74, and consequently will tend to saturate last. In other words, the tampon will start to fill from the inside. Consequently, the fluid reaching the outer surface of the tampon will always arrive on an unsaturated absorbent material and thus will have less tendency to leak hpAâ · from the tampon. To illustrate the advantages of the invention, the following examples are given Unless otherwise specified, all the percentages are given by weight. In each of the examples, the absorbent material has been treated so as to comprise a wetting agent in an amount less than 0.5% by weight of the dry absorbent material. The wetting agent used is a product containing sodium dioctyl sulfo succinate manufactured by the company Rohm &amp; Haas, and sold by this company under the brand Triton GR-5.

13.Example 1

A series of samples is prepared in accordance with the characteristics of the invention. Each of the samples consists of several rectangular absorbent layers measuring 22 cm by 30 cm.

The first sample consists of a first and a second layer, the first layer weighing 18.5 g consists of 90% long fibers of kraft wood pulp and 10% of rayon fibers. The mixture is stabilized with an adhesive binder based on an acrylic latex emulsion and contains 5.7% of this binder relative to the weight of the fibers free of binder. The second layer weighs 15.5 g and consists of 35.0% of bleached sphagnum with a degree of coloring of 70, measured by the Hunter C color scale system, 43.5% of pulp of crushed wood having a CSF value of 80, 8.5% long kraft wood pulp fibers, and 13.0% rayon fibers of 1.5 denier and a fiber length of 3 cm. The mixture is bonded with the same adhesive and in the same proportions as for the first layer.

The second sample consists of a first and a second layer, the second layer weighing 9 g and being moreover identical to that which is described above for the first sample. The first layer consists of 9.0 g of Kraft wood pulp left * air '.-' · «·. '' :: '* h. vThe third sample is made up of 3 layers, the first layer being made of 12.5 g of Kraft wood pulp left in the air, the second layer of 14.5 g of the same material containing sphagnum ^ described next to the first sample, and the third layer consisting of a single sheet of 2.5 g of a cellulose sheet

These samples are tested as follows to determine their preferential liquid retention capacity. Each sample is placed on a flat surface, the first layer upwards, and 30 cm 'of a 1% by weight NaCl solution are deposited

14. "u center of the first layer of each sample. The liquid is allowed to diffuse into the sample for 20 minutes. Then, a 7.5 cm diameter disc is punched in the center of the sample at the point of deposition of the liquid and the fluid retained per unit weight of each layer of each sample is measured. The results are given in Table 1 below:

TABLE I

Echanti 1 Ion Description of the layer Distribution of the fluid

<td> 1</td><td>1st layer:</td><td>K raft (linked,)</td><td>(cc / gm) 2.0</td>

<td></td><td>2nd layer:</td><td>sphai gene</td><td> 4,8</td>

<td> 2</td><td>1st layer:</td><td>Kraft (defibrated)</td><td> 2,5</td>

<td></td><td>2nd layer:</td><td>sphai gene</td><td> 5,55</td>

<td> 3</td><td>1st layer:</td><td>Kraft (defibrated)</td><td> 1,45</td>

<td></td><td>2nd layer:</td><td>sphagnum</td><td> 4,55</td>

<td></td><td>3rd layer:</td><td>fissu / cellulose</td><td> 1,25</td>

As can be seen in Table 1, the juxtaposition of the layers of the samples in accordance with the characteristics of the invention results in the unique preferential distribution of the fluid in accordance with the invention. In particular, 2.2 to 3.13 times more fluid is retained in the sphagnum layer compared to the closest 'retention layer.

Example 2.

A series of periodic towels are prepared with the structure shown in Figures 1 and 2. In particular, the towels have a total length of 25 cm and a total width of 7 cm. They are armed with a non-woven sheath made of 100% of rayon fibers weighing 21g per square meter. To facilitate manufacturing, the samples are lined with a single sheet of fabric which covers the polyethylene barrier layer of 0.012 mm thick and which is placed under the non-woven sheath.

Each towel is lined with an absorbent element comprising several layers, and in each example, the upper layer (closest to the side in contact with the body) and lower layer (the closest to the side in contact with the garment) of the element. are both layers of 4 g of bleached, defibrated, air-dried Kraft wood pulp, comprising 90% split wood pulp and 10% hardwood pulp. The intermediate layer of the absorbent element consists of the following material for each sample, sphagnum and crushed wood pulp ......................... .......

comprising 90% soft wood pulp and 10% hard wood pulp. The intermediate layer of the absorbent element consists of the following material for each sample, the sphagnum and crushed wood pulp being the same as those described for Example 1.

Control samples: a layer of raw cellulose sheet consisting of 3 sheets of treated cellulose fabric folded 4 times to obtain a total of 12 sheets, weighing 1.55 g.

Samples A and B: A second layer (from the top) in raw cellulose wadding identical to that of the second layer of the control samples and a third layer consisting of 35.0% sphagnum, 43.5% wood pulp crushed, 8.5% long-fiber Kraft wood pulp and 13.1% rayon fiber.

Sample 0: An intermediate layer having a laminated structure with an upper layer of wood pulp, a central layer of a mixture of 40% sphagnum, 500 of ground wood and 10% of Kraft pulp, and a lower layer of pulp of wood ; the laminated structure weighing 4 g and being bound overall with 5% of adhesive per gram of material free of adhesive.

Sample D: An intermediate layer consisting of 1.55 g of a mixture comprising by weight 40% of sphagnum, 50% of ground wood and 100 of Kraft wood pulp, the layer being bound by approximately 4% by weight of adhesive .

Sample E: An intermediate layer of laminated structure having an upper layer of the same composition as that of the intermediate layer of sample D, and a lower layer composed of wood pulp. The two layers being linked by approximately 4% by weight of adhesive, each layer weighing 1.2 g.

The samples are all tested by introducing a synthetic menstrual fluid at the top of the towel at a rate of 3.1 cm per hour, for 2 hours, which constitutes a total supply of liquid of 6.2 CC. The samples are then re-weighed to measure the distribution of fluid retention and the results are shown in Table 2 below.

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17-. These results show that the intermediate layer of the control samples does not retain more than 1.6 and 1.7 times the amount of fluid in the nearest retention layer. On the other hand, the layer containing sphagnum of the samples produced in accordance with the invention retains from 2.2 to 5., times more fluid than the nearest retention layer. Also in contrast to the control samples, the closest retention layer was the top layer. It can be seen that the lower layer of the samples produced according to the invention has retained at most only a very small percentage of the total fluid absorbed.

Example 3

<img file="LU80952A1_D0007.tif" />

A series of samples of periodic towels were produced with the general structure described with reference to FIGS. 3 and 4. In each case the towels have a total length of 20 cm and a width of 6 cm. The porous sheath is a 100% rayon nonwoven fabric and a 0.012 mm thick polyethylene film is used as the barrier layer. The material folded back in C consists of approximately 2.45 g of 85% of wood pulp and 15% of rayon linked by 1.5% by weight of an adhesive. In the control samples, the absorbent layer placed inside the folds of C consists of 3 sheets of 85% wood pulp and 15% of rayon bound by 1.5% of adhesive and having a total weight of 3.7 g. Samples produced in accordance with the invention are filled with an inner layer consisting of 35.2% by weight of sphagnum, 44% of pulp of crushed wood, 8.8% of pulp of Kraft S long fiber and 12% of rayon, bonded by o, 5% by weight of adhesive. The samples were tested in vitro, using a synthetic meritruel fluid, deposited at a flow rate of 3 cm 3 per hour for 3 hours, ie a total supply of 9 cm per towel. The towels were then weighed to measure the distribution of the fluid retained in each layer and the results are given in Table 3 below.

?

TABLE 5

Sample. &lt;

&gt; $&gt; of fluid in the G-fold of fluid in the central control layer, sphagnum layer

37,0

20,0

As can be seen, the central layer of 1¹ control sample retains only 1.6 times more fluid than the folded layer C while in the sample produced according to the invention it retains 4.0 times more.

The samples with the structure described above were tested in vivo by two menstrual subjects, users 1 and 2. Each user carried samples of control and sphagnum core layer during the active part of the day. The towels were returned and the distribution of the menstrual fluid retained in each of the components was measured and is shown in Table 4 below:

TABLE 4

<td> 20</td><td>exchanged ple</td><td>Utilisa- tor</td><td>Number hours</td><td>Fluid absorbed (g)</td><td>fo retained in layer C</td><td>% retained layer power plant</td>

<td></td><td>Witness</td><td> 1</td><td> 4</td><td> 3,95</td><td> 46,8</td><td> 52,7</td>

<td></td><td></td><td> 2</td><td> 2</td><td> 4,45</td><td> 49,4</td><td> 44,3</td>

<td></td><td>Sphagnum</td><td> 1</td><td> 5</td><td> 4,65</td><td> 18,1</td><td> 71,4</td>

<td> 25</td><td></td><td> 2</td><td> 2,5</td><td> 5,87</td><td> 17,5</td><td> 76,4</td>

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