WO2006058399A2

WO2006058399A2 - A non-woven fabric, a process for obtaining a non-woven fabric, and an absorbent product

Info

Publication number: WO2006058399A2
Application number: PCT/BR2005/000246
Authority: WO
Inventors: José Antonio Pereira; Maria Cristina Guedes Jorge Micheletto; Rubiela Myriam RAMÍREZ LOZANO
Original assignee: Johnson & Johnson Industrial Ltda.
Priority date: 2004-11-30
Filing date: 2005-11-29
Publication date: 2006-06-08
Also published as: BRPI0405305A; WO2006058399A3

Abstract

One describes a non-woven fabric (1) manufactured by the card- and-bind method, produced with a plurality of rayon fibers chemically consolidated by means of a binder, the transition temperature of which is control- led and kept in the range of from OC to -8°C. The resulting non-woven fabric (1) exhibits thickness, softness, liquid-absorption capacity and cleaning capacity much hither than those exhibited by present-day non-woven fabrics formed by card-and-bind methods, due to the increase in the percentage of fiber and decrease in the percentage of binder in the final product. One further describes a process for obtaining the non-woven fabric (1) and an absorbent product provided therewith.

Description

Title: "A NON-WOVEN FABRIC, A PROCESS FOR OBTAINING A NON- WOVEN FABRIC, AND AN ABSORBENT PRODUCT '

The present invention relates to a non-woven fabric, particularly intended for use as a cleaning cloth or a fabric for hygiene, a process for ob- taining the non-woven fabric and an absorbent product made from the non- woven fabric. Description of the Prior Art

Cleaning cloths have been used for years in personal hygiene, by virtue of their effectiveness and capacity of absorbing liquids. For instance, one can cite hygienic cloths used for the hygiene of babies, which generally has a mild perfume and is moisturized with products that promote a soft and delicate cleaning of the skin.

Also, since long ago one knows cleaning cloths for use in households, as for instance for washing dish, cleaning bathrooms and kitchens, among other uses. This kind of cloth, usually known as perfex ® type, is i- nexpensive and may be discarded after having been used a few times, besides being easy to tear into smaller pieces by hand, if necessary or desirable. Due to these characteristics, it has become a very popular product in the cleaning activity. These two examples of cleaning cloths, and many others known since long ago, effectively correspond to non-woven cloth or fabric composed by interlaced fibers with a determined structuring for the product to have a satisfactory performance. Please note that, in a non-woven fabric, the fibers are not sewn, but rather interlaced by various processes, which will be des- cribed later.

As a rule, one may use fibers of polymeric material or natural fibers, such as cellulosic fibers.

Whatever the particular constitution, however, the non-woven fabrics should have determined specific characteristics, mainly as far as their softness and thickness are concerned, in addition to good liquid-absorption and cleaning properties (which correspond to the capacity of the non-woven fabric absorbing and retaining dirt, instead of merely spreading it). The manufacture of a non-woven fabric may be carried out by a number of known manufacturing methods, some of which have been used for quite long, such as thermobonding shaping, spunbonding shaping, card and bind shaping, air-laid shaping, spunlace shaping, meltblown shaping, hy- drospun shaping, among others.

Of all the above-mentioned methods, the one that enables the obtention of softer, thicker and absorbent non-woven fabrics is the spunlace method. However, the manufacture cost of a non-woven fabric by this method is the highest of all. On the other hand, the thermobonding method, due to its particularities, renders difficult the manufacture of a non-woven fabric that is soft, thick and has good liquid-absorption capacity, since the products obtained with this method usually exhibit exactly opposed characteristics. So, even though the cost of manufacturing a non-woven fabric by thermobonding is low, the interest is not very great, due to the not very desirable properties of the final product.

The card-and-bind method is an intermediate solution, since it enables one to obtain a non-woven fabric with acceptable properties of softness, thickness and liquid-absorption capacity, coupled to the fact of enabling the manufacture of the product at a cost that is not so high as that of the spunlace method.

For the manufacture of a non-woven fabric, especially those intended for personal hygiene, one should aim at a product having high thickness, good softness and high liquid-absorption and cleaning capacity (as al- ready mentioned, the capacity of absorbing and retaining dirt, instead of merely spreading it).

The high thickness is achieved with a large number of fibers existing in a determined unit of area of the non-woven fabric, in case the resulting product has a high specific weight. In practical numbers, a non-woven fabric begins to exhibit a thickness considered to be high when it has a specific weight (or weight in grams per square meter) of about 35 gm2 or higher.

The softness, which is a subjective feeling, is achieved when the- re is a large number of free ends of fibers in a determined unit area of the non-woven fabric. However, when adhesive elements of union between fibers (glues, etc.) are used or when the union is made by fiber fusion, there is a reduction of the free ends of fibers, which reduces the feeling of softness. Therefore, the softness depends upon the specific weight of the non-woven fabric and also upon the method used for interlacing these fibers.

The capacity of absorbing liquids is directly related to the existence of interstitial spaces between the fibers, hereinafter called spaces between fibers. In this case, a low specific weight of the non-woven fabric (few fibers per unit area) results in a greater absorption capacity, due to the increase in spaces between fibers.

Finally, the cleaning capacity is linked, in addition to the volume of the spaces between fibers (which in essence defines the volume of liquid which the non-woven fabric will have the capacity of absorbing), to the pola- rity of determined fibers, which use the linking of hydrogen bridges with the water to be absorbed. In this regard, it should be noted that the fibers resulting from regenerated cellulose, commonly known by those skilled in the art as rayon or viscose, exhibit this polarity and, therefore, This linking brings about an increase in the capacity of the non-woven fabric maintaining the water in the spaces between fibers (by means of the hydrogen bridges).

Therefore, the properties of water absorption and cleaning capacity are linked to the quantity of spaces between fibers and to the type of fiber used in the composition of the non-woven fabric.

It is then evident that a non-woven fabric of reduced specific wei- ght exhibits a good capacity of absorbing liquids, but on the other hand it will have a reduced thickness and little softness, for which reason the users might consider a product to be "poop", cheap or low quality.

On the other hand, a non-woven fabric with a high specific weight, the fibers of which are united by means of adhesive elements or by thermofusion will exhibit high softness and thickness, being recognized by the consumer as a high-quality, soft product of "velvety" touch. And, in case one uses cellulosic fibers, it will have a good performance in absorption ca- pacity and cleaning capacity, due to the inherent polarity of this kind of fiber.

With regard to the fibers used in the composition of a non-woven fabric, one should always aim at the use of rayon fibers, instead of polymeric fibers (polypropylene, polyethylene, polystyrene, etc.), since the latter are substantially apolar.

The meltblown and spunbonding methods do not enable the use of rayon fibers, thus being non-desirable, whereas the thermobonding method accepts the utilization of a determined percentage of rayon, even though it needs a determined percentage of polymeric fibers. So far, one has not developed a non-woven fabric, particularly manufactured by the card-and-bind method, that exhibits high values of thickness, softness, absorption capacity and cleaning capacity, thus having a performance substantially equivalent to that of a non-woven fabric obtained by the spunlace method, but having a lower manufacture cost, which is inhe- rent in the method of manufacturing it. Objectives of the Invention

A first objective of the present invention is to provide a non- woven fabric, as for example a cleaning cloth, manufactured by the card-and- bind method and exhibiting values of thickness, softness, absorption capacity and cleaning capacity substantially equivalent to those exhibited by a non- woven fabric obtained by spunlace, but having a considerably lower manufacture cost.

A second objective of the present invention is to provide a process for manufacturing the non-woven fabric mentioned above. Finally, a third objective of the present invention is to provide an absorbent product provided with the non-woven fabric of the present invention. Brief Description of the Invention

The first objective of the present invention is achieved by means of a non-woven fabric, particularly a non-woven fabric for use in cleaning or personal hygiene, comprising a plurality of individual fibers consolidated by at least one adhesive agent by the card-and-bind method, additionally compri- sing a percentage substantially equal to or lower or higher than 75% of fibers and a percentage substantially equal to or lower or higher than 25% of adhesive agent with transition temperature (Tg) substantially ranging from O⁰C to - 1O⁰C. The second objective of the present invention is achieved by means of a process for obtaining a non-woven fabric, particularly a non- woven fabric as defined in the preceding paragraph, characterized by comprising the following steps: step (i): preparing and positioning a plurality of fibers in at least one mixing chamber of an equipment; step (ii): feeding the plurality of fibers correctly positioned on at least a card; step (iii): applying a binder for consolidating the plurality of fibers; and - step (iv): polymerizing the binder;

Finally, the third objective of the present invention is achieved by means of an absorbent product, particularly for absorbing bodily exudates, which comprises at least one layer constituted by a non-woven fabric comprising a plurality of individual fibers consolidated by means of at least one a- dhesive agent by the card-and-bind method, and that additionally comprises a percentage substantially equal to or higher than 75% of fibers and a percentage substantially equal to or lower than 35% of adhesive agent with a transition temperature (Tg) substantially ranging from O⁰C to -10⁰C.

The present invention has, as an advantage, the fact of enabling one to obtain a non-woven fabric produced by the card-and-bind method that exhibits great softness feeling, high thickness and optimum liquid-absorption capacity and cleaning capacity, while maintaining the manufacture cost reduced. Consequently, the market-penetration potential of this product is enormous. An absorbent product provided with the non-woven fabric of the pre- sent invention has the same advantages, and its potential of penetration into the consumer market is also high. Brief Description of the Drawings The present invention will now be described in greater detail with reference to an embodiment represented in the drawings. The figures show:

- Figure 1 - an enlarged view of a non-woven fabric of the prior art, produced by the spunlace method; - Figure 2 - an enlarged view of a non-woven fabric of the prior art, produced by the thermobonding method;

- Figure 3 - an enlarged view of a non-woven fabric of the prior art, produced by the card-and-bind method; and

- Figure 4 - an enlarged view of the non-woven fabric of the pre- sent invention.

Detailed Description of the Figures

According to a preferred embodiment and as can be seen in figure 4, the non-woven fabric 1 of the present invention is manufactured by the card-and-bind method and exhibits high thickness, great softness and high properties of absorption capacity and cleaning capacity, while maintaining a reduced manufacture cost, especially if compared with the manufacture cost of a non-woven fabric produced by spunlface.

Evidently, in order for the manufacture of the non-woven fabric 1 of the present invention to be economically feasible, it has to be produced by using the same card and bind equipments used in the production of the present-day non-woven fabrics (see figure 2).

As already mentioned before, the card-and-bind method of manufacturing non-woven fabrics uses a mixture of polymeric fibers and rayon fibers, or preferably 100% of rayon fibers, which are previously prepared and correctly positioned ion a mixing chamber and then fed onto at least one card, so as to compose at least one mesh or fibrous web, after which they are consolidated by means of a resin or adhesive agent.

Evidently, one may use 100% of polymeric fibers, but the liquid- absorption capacity and the cleaning capacity of the final non-woven fabric will be considerably reduced. One may further use rayon fibers with different titer or denier (quantity that corresponds to the mass in grams of 9,000 meters of the fiber), lengths and widths, mixed together, for the purpose of achi- eving alterations in the properties of softness, thickness, absorption capacity and cleaning capacity.

By preference, one uses a plurality of cards in order to enable the formation of a final fibrous mesh. Further preferably, the rayon fibers receives addition of at least one opacity agent (titanium dioxide - TΪO2, or equivalent), which imparts a highly desirable white mat appearance to the non-woven fabric. Evidently, any other additives that are necessary or desirable to obtain a determined effect on the final product may be used. After formation of the fibrous meshes, they are treated with a large amount of water in one of more specific chambers. The preferred configuration of the non-woven fabric of the present invention is treated with water in a chamber called Keysak Unity, but evidently other pieces of equipment may be used. The treatment with water promotes hydro-cohesiveness and a desired level of residual moisture on the fibrous mesh.

The control over this process in order to maintain a determined range of residual moisture on the fibrous mesh is extremely important, inasmuch as it optimizes the performance of the adhesive agent in binding toge- ther the fibers (hereinafter called binder), which is applied through the fibrous mesh (by contact, aspersion, spraying, pulverization or any other adequate means) during the chemical consolidation of the mesh (which corresponds to the "birth" of the non-woven fabric proper).

It is important to note that the use of a binder in forming expan- ded foam (foamed formulation binder) is not desirable, since the interpenetra- tion of this product in the fibrous mesh does not occur satisfactorily.

All the formulations relating to the non-woven fabric 1 of the present invention consider the adjustment of the glass transition temperature (Tg), the contents of constituent solids and controlled addition of biocidal pre- servative additive provided with non-ionic, anionic and cationic molecules, approved or desirable.

Co-biocidal molecules such as those belonging to the family of O

the tetracetic ethylene diamine acids may also be used in association with said biocides.

Such preservative additives may be formulated in an independent or associated way, regardless of their ionic nature. Evidently, any other substances may be used, if necessary or desirable.

The application of the binder in the moisturized fibrous mesh, in a controlled and adequate way, is preferably carried out by means of an applying roller system. By preference, the applying rollers used are those identifi- ed as "print unit #185035-23DWLPI".

This kind of identification is suitable for defining the type of binder-applying roller surface, especially as far as its geometry and the amount of binder effectively transferred from the roller to the fibrous mesh. For e- xample: • the reference #185035 indicates that the depth of the compression relief lines of the binder-applying roller is of 1/185 inch and the thickness of the lines if of 1/35 inch;

• the reference #23DWLPI indicates 23 diagonal relief lines per inch of the binder-applying roller; • the rate of transfer of binder from the roller to the fibrous mesh is of about 380 kg per 10,000m2.

Evidently, if necessary or desirable, one may use any other types of applying rollers, which may or may not have other binder-transfer rates. With regard to the rayon fibers, preferably (but not compulsorily) they exhibit the following characteristics:

• titer: preferably between 0.8 and 2.5 denier, more preferably between 1.2 and 1.5 denier;

• length: preferably between 20 and 60 millimeters, more prefera- bly between 3.8 and 50 mm;

• pigmentation: preferably opaque, due to the presence of opacity agent (TiO2, between 1.0% and 2.0%); • additional characteristics: preferably washable, antistatic and of cohesive nature (between 0.1 % and 0.3%).

The binder used in the preferred embodiment of the non-woven fabric of the present invention exhibits the following characteristics:

• nature: preferably a self-crosslinkable non-ionic and/or anionic acrylic emulsion resin; the resin should be used in isolation or in mixture so that one can achieve a correct adjustment of the temperature Tg (mentioned before);

• polymer: preferably an ethyl acrylate / butyl acrylate / acrylonitrite terpolymer with temperature Tg ranging from 8⁰C to 12°C,mixed with at least one ethyl acrylate homopolymer with temperature Tg ranging from -8⁰C to - 15⁰C;

• temperature Tg: preferably adjustable in a range from O⁰C (zero) to -1O⁰C, the adjustment being made by means of mixtures of resins within determined parameters.

Table 1 below shows the chemical characteristics of the binder, before and after it has solidified. TABELE 1

The binder exhibits the following characteristics, when still wet (wet binder) and dry (dry binder), respectively:

• wet binder in the range from 0.80% to 1.10%, representing the transfer of approximately 0 (zero) to 720 kg per 10,000%m2;

• dry binder: preferably corresponds to about 18% to 25% of the polymerized binder, representing the final approximate composition of the non-woven fabric 1.

Within the ranges determined in Table 1 above, the variables of the process of manufacturing a non-woven fabric 1 as defined above, which is also a novel and inventive invention, should be controlled so that one can achieve:

• polymer mixture: Tg of -5⁰C to O⁰C (zero);

• retention of polymerized binder: 18% to 25%;

• rayon contents between 75% and 82%. The values traction resistance (grams/inch) of the non-woven fabric 1 of the present invention may be found below:

• in the direction of the length (dry): minimum of 3,00 g/inch;

• in the direction of the length (wet): minimum of 1 ,500 g/inch;

• in the direction of the width (dry): minimum of 500 g/inch; * in the direction of the width (wet); minimum of 250 g/inch.

On the other hand, the ratio between the traction resistance in the direction of the length and in the direction of the with of the non-woven fabric 1 presents the following values:

• length/width (dry): maximum ratio of 8:1 ; • length/width (wet): maximum ratio of 8:1.

The thickness has relationship with the specific weight (mi- crons/g/m2), and presents a minimum value of 6.0 : 1.0.

The absorption capacity too has relationship with the specific weight (% / g/m2) and presents a minimum value of 23,0 : 1.0. During the formation of the final fibrous mesh, preferably three or four cards with superposition of three or four multi-layer fibrous meshes are used.

The residual wetness of the mesh after it has been treated with water should preferably range from 75% to 86% before application of the binder, but evidently these values may vary.

The process for obtaining the non-woven fabric of the present invention, which has already been described in a diffuse way above, essenti- ally comprises the following steps: step (i): preparing and positioning the plurality of fibers in at least one mixing chamber of an equipment; step (ii): feeding the plurality of correctly positioned fibers to at least one card; step (iii): applying binder to consolidate the plurality of fibers; and step (iv): polymerizing the binder.

The application of binder is preceded by the step of treating the plurality of fibers with a large quantity of water, already mentioned before. As mentioned, the step of applying binder is preferably carried out by the mentioned applying-roller system, which comprises rollers identified as "print unit # 185035-23DWLPI".

The polymerization of the binder, as already mentioned, is preferably carried out by means of a contact surface heated between 145⁰C an 16O⁰C during a time of 30 to 60 seconds, but evidently it may vary, if necessary or desirable, for instance as a function of the composition of the binder.

The non-woven fabric 1 produced by the process disclosed now has the preferred final composition containing from 75% to 80% of rayon fibers and from 20% to 25% of binder. Its specific weight (or weight in grams per square meter) preferably ranges from 24 g/m2 and 50 g/m2, and more preferably about 38 g/m2, even though these values may vary, if necessary or desirable.

During the process of manufacturing the non-woven fabric 1 , the polymerization of the binder is preferably carried out by a contact surface heated between 145⁰C and 165⁰C, for 30 to 60 seconds. It is evident that these values may vary, as well as the way of carrying out the polymerization, if necessary or desirable.

By preference, a minimum of markings of the fibrous mesh from the cards until the application of binder, if necessary. A range of 15% to 20% is sufficient and acceptable to prevent the volume of the fibrous mesh from being reduced.

Evidently, the non-woven fabric 1 of the present invention may include any other substance not mentioned in this detailed description, but even so it remains included in the scope of protection of the present invention, defined in the accompanying claims.

A comparative table (Table 2) of the non-woven fabric 1 of the present invention vis-a-vis the non-woven fabric presently obtained by the card-and-bind method enables one to verify the enormous advance as far as the properties presented by the invention are concerned. TABLE 2

A careful analysis of Table 2 enables one to conclude unmistakable that the non-woven fabric 1 of the present invention exhibits improvements in all the fields of the alteration column, which means that its performance is superior in thickness, softness, liquid-absorption capacity and cle- aning capacity, using the same area weight in grams per square meter (38g/m2) and, therefore, the same manufacture cost of the non-woven fabric manufactured at present by the card-and-bind method.

The alterations in items A, B, C, D, E, M, N and O impart benefits to the non-woven fabric 1 of the present invention in general appearance of the product, thickness, softness and liquid-absorption capacity.

The alterations in items D, E₁F, J, K, L, M, N and O impart benefits to the non-woven fabric 1 of the present invention in softness, smoothness, utilization comfort, touch and cleaning capacity.

Finally, item J greatly increases the feeling of softness of the non-woven fabric 1.

It is very important to point out that the non-woven fabric 1 of the present invention exhibits a considerable reduction of the quantity of binder (28%, see items B, E and H), concomitantly with the increase in the amount of fibers (about 15%, see items D, F, G, I, J, K, L). And the most important thing is that, in addition to the considerable increase in the quantity of fibers, which brings an increase in the quantity of free ends of fibers (imparting greater feeling of softness and increase in the capacity of effecting the polar linking with the water molecules by means of the linking by hydrogen bridges), the smaller amount of binder causes the- se ends to remain effectively free, and not agglutinated, which maintains the properties at a high level. Moreover, a smaller amount of binder increases the availability of spaces between fibers (which have not been filled due to the reduction of the adhesive used), increasing the absorption capacity of the non-woven fabric 1. Finally, it is important to note the increase in the quantity of fibers of the non-woven fabric (area weight in grams per square meter), which would bring about an increase in the manufacture cost with respect to the non-woven fabric presently produced by the card-and-bind method, but the reduction in the use of binder is a counterbalance that maintains the cost reduced.

Due to the increase in the properties desired by the consumer, coupled with contained manufacture cost, the non-woven fabric 1 of the present invention exhibits great potential of sales on the consumer market, mainly in countries where the average population does not have a high buying power and, for this reason, cannot afford to consume a non-woven fabric manufactured by spunlace. After manufacture, the non-woven fabric is correctly packed and may be moistened with perfumes, suave fragrances, etc., in order to be perfumed when it is used, maximizing the feeling of softness, absorption capacity and cleaning capacity.

Finally, it should be noted that an absorbent product for absor- bing bodily exudates, as for example a sanitary napkin, a disposable diaper, a breast protector, or any other, is also a novel and inventive invention, included in the protection scope of the accompanying claims.

Essentially, the absorbent product comprises at least one layer constituted by the non-woven fabric disclosed now, which is provided with a plurality of individual fibers consolidated by means of at least one adhesive agent by the card-and-bind method, and additionally comprises a percentage substantially equal to or higher than 75% of fibers and a percentage substantially equal to or lower than 25% of adhesive agent with transition temperature (Tg) substantially in the range from O⁰C to -10⁰C. A preferred embodiment having been described, one should understand that the scope of the present invention embraces other possible variations, being limited only by the contents of the accompanying claims, which include the possible equivalents.

Claims

1. A non-woven fabric, particularly a non-woven fabric for use in cleaning or personal hygiene, comprising a plurality of individual fibers consolidated by means of at least one adhesive agent by a card-and-bind me- thod, characterized by comprising a percentage substantially equal to or higher than 75% of fibers and a percentage substantially equal to or lower than 25% of adhesive agent with transition temperature (Tg) substantially ranging from O⁰C to -10⁰C.

2. A non-woven fabric according to claim 1 , characterized by comprising regenerated-cellulose fibers or rayon.

3. A non-woven fabric according to claim 1 , characterized by comprising a mixture of polymeric fibers and rayon fibers.

4. A non-woven fabric according to claim 1 , 2 or 3, characterized in that the adhesive agent, or binder, is preferably a self-crosslinkable anionic acrylic resin.

5. A non-woven fabric according to claim 1 , 2, 3, or 4, characterized in that the binder corresponds to an ethyl acrylate / butyl acrylate / acr- ylonitrite terpolymer with transition temperature (Tg) ranging from +8⁰C to +12⁰C, mixed with an acrylate ethyl homopolymer with transition temperature (Tg) ranging from -8⁰C to -15⁰C.

6. A non-woven fabric according to any one claims 1 to 5, characterized by being produced from three or four multi-layer fibrous meshes.

7. A non-woven fabric according to any one of claims 1 to 6, characterized by having a specific weight or surface-area weight in grams per square meter ranging from 24 to 50 g/m2.

8. A non-woven fabric according to claim 7, characterized by having a specific weight or surface-area weight in grams per square meter of 38g/m2.

9. A non-woven fabric according to any one of claims 1 to 8, characterized by comprising a percentage of 75% to 82% of rayon fibers.

10. A non-woven fabric according to any one of claim 1 to 9, characterized by having substantially 372 fibers per cm2.

11. A non-woven fabric according to any one of claims 1 to 10, characterized by having substantially 744 fiber ends per cm2.

12. A non-woven fabric according to any one of claims 1 to 11 , characterized in that its average thickness is substantially 255 microns.

13. A process for obtaining a non-woven fabric, particularly a non-woven fabric (1) as defined in claims 1 to 12, characterized by comprising the following steps: step (i): preparing and positioning a plurality of fibers in at least one mixing chamber of an equipment; - step (ii): feeding the plurality of fibers correctly positioned on at least a card; step (iii): applying a binder for consolidating the plurality of fibers; and step (iv): polymerizing the binder.

14. A process according to claim 13, characterized in that the step (iii) of applying binder is preceded by a step of treating the plurality of fibers with a large amount of water.

15. A process according to claim 13, characterized in that the step (iii) is preferably carried out by means of an applying-roller system.

16. A process according to claim 15, characterized in that the applying-roller system comprises rollers identified as "print unit #185035- 23DWLPl\

17. A process according to claim 13, characterized in that the step (iv) of polymerizing the binder is preferably carried out by means of a contact surface heated between 145⁰C and 160⁰C during a time of 30 to 60 seconds.

18. A process according to claim 13, characterized in that the step (i) comprises adding to at least an opacity agent to said plurality of fibers.

19. An absorbent product, particularly for absorbing bodily exudates, characterized by comprising at least one layer constituted by a non- woven fabric comprising a plurality of individual fibers consolidated by means of an adhesive agent by the card-and-bind method, and comprising additionally a percentage substantially equal to or higher than 75% of fibers and a percentage substantially equal to or lower than 25% of adhesive agent with transition temperature (Tg) substantially ranging from O⁰C to -1O⁰C.

20. An absorbent product according to claim 19, characterized in that the non-woven fabric comprises regenerated cellulose fibers or rayon.

21. An absorbent product according to claim 19, characterized ion that the non-woven fabric comprises a mixture of polymeric fibers and rayon fibers.

22. An absorbent product according to claims 19, 20 or 21 , characterized in that the adhesive agent, or binder, is preferably a self- crosslinkable anionic acrylic emulsion resin.

23. An absorbent product according to claim 19, 20, 21 , or 22, characterized in that the binder corresponds to an ethyl acrylate / butyl acr- ylate / acrylonitrite terpolymer with transition temperature (Tg) ranging from +8⁰C to +8⁰C, mixed with an ethyl acrylate homopolymer with transition temperature (Tg) ranging from -8⁰C to -15⁰C.

24. An absorbent product according to any one of claims 19 to

23, characterized ion that the non-woven fabric is produced from three or four multi-layer fibrous meshes.

25. An absorbent product according to any one of claims 19 to

24, characterized in that the non-woven fabric has a specific weight surface weight in grams per square meter ranging from 24 to 50g/m2.

26. An absorbent product according to claim 25, characterized in that the non-woven fabric has a specific weight surface weight in grams per square meter of 38g/m2.

27. An absorbent product according to any one of claim 19 to 26, characterized in that the non-woven fabric comprises a percentage of from 75% to 82% of rayon fibers.

28. An absorbent product according to any one of claims 19 to

27, characterized in that the non-woven fabric has substantially 372 fibers per cm2.

29. An absorbent product according to any one of claim 19 to 28, characterized in that the non-woven fabric has substantially 744 fiber ends per cm2.

30. An absorbent product according to any one of claims 19 to 29, characterized in that the average thickness of the non-woven fabric is substantially 255 microns.