WO1995002384A1

WO1995002384A1 - Hygienic absorbent article

Info

Publication number: WO1995002384A1
Application number: PCT/US1994/008086
Authority: WO
Inventors: Andreo Cesar Eduardo Aledo
Original assignee: Johnson & Johnson
Priority date: 1993-07-13
Filing date: 1994-07-12
Publication date: 1995-01-26
Also published as: AU7366194A; BR9302840A

Abstract

The present invention refers to a hygienic absorbent article (1) containing a permeable layer (2), an absorbent nucleus (3) and an impermeable lining (4). The layer (2) is made from non-woven fabric, which permits the rapid passage of the body fluids, that are absorbed by the absorbent nucleus (3) and retained by the impermeable lining (4). The lining (4) and the layer (2) are sealed, forming a surface edge (6), the nucleus (3) being enclosed within the internal space of the edge (6). In the lining (4) a fold (9) is foreseen, limited by the folding lines (10) which form recesses (11). The fold (9) permits the expansion of the nucleus (3) in a direction away from the user's body, as the nucleus receives the body fluids.

Description

Specification For a Patent For Invention for

Hygienic Absorbent Article

The present invention refers to disposable hygienic absorbent articles such as, diapers, absorbents, surgical dressings, incontinency absorbents and the like.

Absorbent products are known and used to absorb and retain liquids or other body Fluids thereby providing comfort and security for the users.

The main purpose of this kind of article is the obtention of a product having a high level of absorbent capacity, security and comfort, maintaining close contact with the user's body while keeping the skin dry, which, apartfrom increasing the user's feeling of well being, provides more security by guaranteeing total absorbence of the body fluids.

A few patents dealing with this matter may be cited. Brazilian Patent Application PI 8464347-4 refers to a hygienic protection product having a high level of impact capacity and fluid retention. The absorbent nucleus consists of a superstructure comprised of a loosely compacted cellulosic fiber mesh, corrugated and stabilized, either by means of adhesives, heat sealing or other processes, which prevents the loosening of the corrugation as the product receives the liquid. In this manner, the product will retain the absorbed liquid, avoiding leakages even though pressure may be applied during use. Drazilian Patent PI 9005475 refers to a comformable structure and absorbent article comprised of elements that permit relative movement between themselves, avoiding leakages even when subject to pressure.

PCT Application US91/07769 refers to a hygienic absorbent having elements which may be separated in several directions in relation to the remaining components of the same article, permitting constant contact of the article with the user, utilizing compressive forces exercised by the inner thighs to improve contact.

Absorbent articles are usually comprised of an absorbent nucleus placed between a liquid permeable layer and an impermeable lining.

The impermeable lining is meant to prevent the leakage of the fluid contained in the absorbent nucleus, said lining being usually comprised of a plastic film, such as polyethylene, polyethylene foam or other material treated so as to become totally impermeable to liquids.

The permeable layer which remains in touch with the user's body permits the quick passage of the liquids flowing from the body, thus avoiding an uncomfortable and undesired dampness.

The permeable layer may or not be provided with perforations, being commonly made of non-woven fabric, of the kind suitable for facilitating the radial flow of the body fluids, so as to ensure that the contact surface remains dry. The absorbent nucleus is suitable for quickly absorbing and retaining the body fluids, being comprised of wood pulp fibers, vegetable pulp, natural or synthetic fibers or any other hydrophile material having a high absorbent capacity.

The structure of the absorbent layer is further provided with super-absorbent materials which have been used for some time in this kind of product, due to their high level of liquid absorbent capacity since they are capable of absorbing a volume of liquid larger than their own weight.

In this case the absorption of large volumes of liquid is possible due to the characteristics of said material, usually polymers, such as starch or polyacrilates, particulate or in fibers, which literally ''hold" the water molecules around them.

However , while absorbing liquid, this material undergoes a swelling with the increase and expansion of the absorbent nucleus.

Since the nucleus is placed between the liquid permeable layer and the impermeable lining, said nucleus remains enclosed between the sealed borders of the layer and the lining that extend over the entire surface of the absorbent product, thus limiting the expansion of the nucleus.

As the nucleus receives the body fluids it will expand. Being limited between the layer and the lining the nucleus tends to alter the original configuration of the product (unexpended), mainly in the direction of the permeable layer making it convex and prone to lateral leaks of the content during use, causing discomfort and a feeling of insecurity for the user. The hyg i en ic absorbent article of the present invention is meant to solve the problems which exist in the art, providing the means to permit the controlled expansion of the nucleus, without the occurrence of an increase in the possibility of leakages.

A further purpose of the present invention is to provide an absorbent article that prevents lateral leakages, permitting greater security for the user, even in those caseE of large discharges of body fluids.

Summary of the Invention

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A hygienic absorbent article is presented, of the kind suitable for absorbing body fluids, of small, medium or large quantities, said article remaining in close contact with the user's body, thus maintaining it dry, since the body fluids are quickly absorbed, passing through the permeable layer, being absorbed by the absorbent nucleus and retained by the impermeable lining which avoids leakages.

The absorbent article of the present invention is comprised of a flexible permeable layer, an impermeable lining and an absorbent nucleus placed internally between the layer and the lining. The layer is fixed to the lining forming a surface edge in the interior of which the nucleus is placed, the impermeable lining having larger dimensions than those of the permeable layer, thus forming at least one fold in the lining.

The fold permits that the nucleus expand in a direction opposite the user's body, maintaining the form of the surface in contact with the user's body unaltered, thus eliminating or minimizing the possibility of leakages. Other advantages and uses provided by the present invention will be tetter understood by the following description.

Brief Description of the Drawings

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Figure 1 is a perspective view of the absorbent article of the present-invention, in a preferred embodiment.

Figure 2 is a frontal view of the article that better illustrates the liquid permeable layer.

Figure 3 is a back view of the absorbent article showing with more details the liquid permeable lining.

Figure 4 is a lengthwise cross-section view of the referred article; and

Figure 5 is a perpendicular cross-section view of the article of the present invention.

Detailed Description of the Invention

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In a preferred embodiment of the invention, the absorbent article 1 is provided with a liquid permeable layer 2, an absorbent nucleus 3 and an impermeable lining 4. The layer 2 is comprised of a non-woven fabric 5, which may be provided with a plurality of orifices, a plurality of hexagonal perforations 5a, or any other means that permit a rapid passage of the body fluid to the nucleus, so as to maintain dry the contact with the user, thus increasing comfort.

The absorbent nucleus 3 is comprised of an absorbent layer constituted by a plurality of wood pulp fibers and superabsorbent materials which permit rapid passage and uniform distribution with a high level of absorption of the body fluids.

The impermeable lining 4 is comprised of polyethylene foam,

polyethylene plastic film or other water repellent material, which purpose is to prevent leakage of the body fluids.

The permeable layer 2 and the impermeable lining 4 are fixed to one another, forming a sealed surface edge 6 which extends over the entire surface of the absorbent article.

The absorbent nucleus 3 is placed between the layer 2 and the lining 4, in such a manner so that there is no relative movement between themselves, that is, the nucleus remains enclosed between the layer 2 and the lining 4, internally with respect to the surface edge 6. Said fact limits the expansion of the absorbent nucleus 3 solely in the area enclosed by the inner border 8 of the edge 6 of the absorbent article 1.

As may be seen, preferably from Figure 2, the inner border 8

internally limits the region of the surface edge 6 which is the sealed surface part of the layer 2 with the lining 4. The expansion of the nucleus will occur gradually in accordance with the absorption of the fluids which flow from the user's body. Therefore, this expansion will occur in the area of the article 1 limited by the inner border 8.

The purpose is to obtain a controlled expansion of the nucleus, so as to maintain substantially unaltered the configuration of the surface of the layer 2.

In order to achieve said objective, a fold 9 is foreseen in the impermeable lining 4 which, in the preferred embodiment, is placed in the lengthwise direction of the article 1, extending over the entire length of the absorbent article.

The re ferred to fold 9 is, preferably, obtained from a folding of the lining 4 , which has a width larger than that of the layer 2. The fold 9 is comprised of two lines of the fold 10, thus forming recesses 11, solely in the part of the absorbent article 1 in which is located the absorbent nucleus 3.

In this way, in the area in the lining 4 in which fold 9 and the recesses 11 are located the absorbent nucleus 3 will expand, filling the space enclosed by the fold 9, as nucleus 3 absorbs the body fluids which flow from the user's body.

The present invention is not limited to the illustrated structure which is a preferred embodiment. The fold 9 may certainly be placed in the transversal direction of the absorbent article 1, positioned in the central part, where there is a larger discharge of the body fluids or dislodged to a more convenient area.

In another embodiment, more than one fold may be foreseen, placed in either the lengthwise or transversal direction of the absorbent article, provided that the function of controlled expansion of the absorbent nucleus be obtained.

In a further embodiment the fold 9 may be "X" shaped so that the ends are fixed to tte surface edge 6 and the controlled expansion of the nucleus occurs in the area of the lining 4 enclosed by the edge 6.

From the above it may be concluded that several amendments may be introduced without, however, departing from the scope of the new concept shewn in the present invention.

Claims

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1. Hygienic absorbent article, comprising a flexible permeable layer (2), an impermeable lining (4) and an absorbent nucleus (3) placed internally relative to the layer (2) and the lining (4), the layer (2) being fixed to the lining (4) forming a surface edge (6) in the interior of which is located the nucleus (3): said impermeable lining (4) having dimensions larger than those of the permeable isyer (2), characterized by the fact that said lining (4) is comprised of at least one fold (9).

2. Article, in accordance with Claim 1, characterized by the fact that at least one folding is a fold ( 9 ) formed by at least two folding lines (10) which result in recesses (11) capable of receiving the expanded nucleus (3).

3. Article, in accordance with Claim 2, characterized by the fact that the fold (9) is placed lengthwise relative to the article (1) so that the recesses (11) expand perpendicularly away from the layer (2) as the nucleus (3) expands.

4. Article, in accordance with Claim 2, characterized by the fact that the at least one fold (9) located in the lengthwise direction of the article (1) is centrally placed with respect to the surface edges (6).

5. Article, in accordance with Claim 4, characterized by the fact that more than one fold (9) is foreseen in the lengthwise direction of the article (1).

6. Article, in accordance with Claim 2, characterized by the fact that the at least one fold is a fold (9) placed in the transversal direction of the article (1) so that the recesses (11) expand away from the layer (2) as the nucleus (3) expands.

7. Article, in accordance with Claim 6, characterized by the fact that more than one fold (9) may be foreseen in the transversal direction of the article (1).

8. Article, in accordance with Claim 6 , characterized by the fact that the transversal fold is centrally placed.

9. Article, in accordance with Claim 1, 2 or 3, characterized by the fact that the fold (9) is "X" shaped, the legs of same being fixed by the surface edge (6), permitting the expansion of the nucleus away from the lining (2),