CZ328999A3 - Absorption articles with removable - exchangeable parts - Google Patents

Abstract

Absorbent articles (60) comprise discontinuous, substantially a liquid impermeable backsheet (62), and an abrasive core (10) arranged between the upper layer (61) and the lower layer (62). The absorbent core (10) includes a plurality of components removable, with access to provided removal operations * at least one gap forming an opening (41) in the lower layer (62). Once removed, they remain in the absorbent article other components of the absorbent core or layers of these components. The aperture (41) in the lower layer (62) may also be added additional components of the absorbent core or layer. In preference the absorbent core (10) embodiment comprises a plurality of components, comprising at least a front portion (20), a rear portion (30) and a a central portion (50). Each of the absorbent members can contain layers of absorbent elements. After saturation by body liquids may be certain components or elements of an absorption the core removed by the backsheet (62) of the absorbent article.

Description

Fť

Absorbent articles with removable- replaceable; components

Technical field

The present invention relates to absorbent articles such as disposable diapers. The invention further relates to absorbent articles having multi-piece absorbent cores.

BACKGROUND OF THE INVENTION

Absorbent articles such as disposable diapers, incontinence pads, training pants, and sanitary napkins generally comprise an absorbent core for receiving and retaining body exudates. The absorbent core typically comprises a fibrous structure, which may be a nonwoven, airlaid structure of natural or man-made fibers, or a combination thereof. The fibrous structures used in these absorbent articles also often contain certain gel materials, commonly referred to as "hydrogels," superabsorbent or "hydrocolloid" materials, to contain large amounts of secreted body fluids. These materials absorb through capillary or osmotic forces or a combination of both.

Alternative absorbent materials capable of providing capillary fluid transfer are open-celled polymeric foams. If properly manufactured, these

open-celled polymeric foams provide the characteristics of capillary fluid acquisition, transfer, and storage required for use in high performance absorbent cores for absorbent articles such as diapers. Absorbent articles containing such foams may also have desirable wet integrity or strength, provide appropriate fit throughout the wear of the article, and may dispense with their shape in use. In addition, absorbent articles comprising such absorbent foam structures could be more easily manufactured on a commercial scale. For example, absorbent foam diaper cores could simply be punched from continuous foam layers and could be designed to have considerably greater integrity and uniformity than airlaid fibrous absorbent cores containing particulate absorbent gelling materials.

In addition to absorbency and ease of manufacture, once again a desirable property of open-cell polymeric foams is the ability to produce shaped or body-adapted absorbent cores having different shape configurations, fluid-absorbing properties, and wear characteristics. Shaped or contoured absorbent cores made of open-celled polymeric foam materials are already described in the diaper manufacturing technique. Shaped or contoured absorbent cores made of open-celled polymeric foam materials having particularly desirable fluid transfer characteristics are described in U.S. Patent 5,147,345 (hereinafter also referred to as ^Σ 345) issued to Young et al. on September 15, 1992 and incorporated herein by reference. The absorbent core of ^T 345 Young et al. it essentially comprises both a fluid acquisition / distribution component and a fluid storage / further distribution component. Fluid Acquisition / Distribution Component • · • ·

is placed within the absorbent core in such a manner that it receives or contacts body fluid that is secreted into the absorbent article by the wearer thereof. The fluid storage / redistribution component is in turn positioned within the article such that it is in fluid communication with the fluid acquisition / distribution component.

Absorbent cores from multiple pieces providing absorption characteristics 345 patent ^and Young et al. are described in a preferred, co-pending application entitled " Molded Absorbent Cores of Multiple Absorbent Material and Method of Manufacture, US Patent Application Numbers and Grant Date: (To be Incorporated After Detection), Filed by Gerald Martin Weber, Gerald Alfred Young, Gregory Wade Taylor and Gary Dean LaVon. Weber et al. discloses shaped absorbent cores comprising a front panel and a back panel. The front portion and the rear portion are in fluid communication with the central portion. This central portion preferably comprises a material generally suitable for receiving / distributing fluid, while the front and rear portions comprise a material generally suitable for receiving / distributing fluid.

Despite advances in absorbent articles and liquid-absorbent absorbent core materials, absorbent articles having multi-component absorbent cores, as well as unit cores, are generally designed to be worn in a single-use manner. Once the fluid acquisition / distribution component is saturated with body exudates such as urine, the entire absorbent article is generally discarded and replaced with a new one. Often parts of the absorbent article are still usable and, except that they are bonded to the absorbent cores, these parts could be further used. In addition to the additional costs and waste associated with • 9

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By degrading reusable materials, it is often uncomfortable to remove and replace the entire absorbent article when the absorbent core components are saturated with liquid.

Absorbent articles with removable absorbent pads are already known in the art. For example, U.S. Patent No. 4,597,762 to Buell, issued July 1, 1986, discloses a disposable absorbent pad for use within an undergarment such as a traditional reusable diaper or disposable diaper. Once saturated, the absorbent pad can be removed and discarded. The absorbent article can then be reused with a new absorbent pad. Buell is a general embodiment of an absorbent article having a continuous, liquid impermeable backing layer (backsheet) and a liquid pervious body-side cover (topsheet), with a removable absorbent core insert disposed therebetween. The absorbent core insert is removed from the side to the body of the article, which necessarily requires that the absorbent article be removed from the wearer. This sensing is often inconvenient and takes time.

Accordingly, it would be desirable to have an absorbent article having removable or replaceable absorbent core components in which the absorbent core components can be removed or replaced without the absorbent article having to be removed from the wearer.

In addition, it would be desirable to have an absorbent article having an absorbent core with removable or replaceable components and a discontinuous (interrupted) backsheet to allow saturated portions of the absorbent core to be removed through a gap in the backsheet to expose the unsaturated portions and allow extended using reusable parts of the absorbent article.

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Further, it would be desirable to have an absorbent article having a continuous backsheet attached to the topsheet about a perimeter having removable or replaceable absorbent core components disposed between the topsheet and backsheet such that access to the absorbent core components is provided by dividing the topsheet and backsheet in advance a predetermined surface to form an opening.

SUMMARY OF THE INVENTION

The invention relates to absorbent articles suitable for absorbing and retaining aqueous body fluids. A preferred embodiment of the absorbent articles of the present invention includes a discontinuous, substantially liquid impermeable backsheet and an absorbent core disposed adjacent the backsheet. The absorbent core comprises at least one, and preferably a plurality of core components that are removable, with an access thereto that provides at least one aperture forming an opening in the backsheet. Once removed, other absorbent core components or layers may remain in the absorbent article. Additional portions of the absorbent core may also be added through the opening in the backsheet.

In a preferred embodiment, the absorbent article comprises a plurality of components comprising at least a front portion, a back portion, and a central portion. Each of the absorbent members may comprise layers of absorbent members. After saturation with body exudates, certain components or elements of the absorbent core may be removed from the absorbent article through the backsheet. Instead of removed saturated components or elements, new, unsaturated components or elements may be placed or, more preferably, after removal • 9 9 99 99 · 9 9 99 99 9999 9999

9 · 99 99 «99999 The saturated unused part or feature remains in the location for use.

In another embodiment, the absorbent article comprises a liquid pervious topsheet and a continuous substantially liquid impermeable backsheet attached around the periphery to the topsheet. The predetermined circumferential surface is (s) separable, whereby the topsheet and the backsheet may be separated and an aperture may be formed providing access to the removable absorbent core components disposed between the topsheet and the backsheet. In a particularly preferred embodiment, the absorbent core comprises front and rear absorbent members in fluid communication with the central absorbent member. The central absorbent member preferably has a fluid acquisition / acquisition / distribution characteristic, while the front and rear absorbent members preferably have a storage / redistribution characteristic.

BRIEF DESCRIPTION OF THE DRAWINGS

Although this description is completed by the claims that specifically define and clearly claim the invention, it is believed that it will be better understood from the following description taken in conjunction with the accompanying drawings, in which:

Giant. 1 is a perspective, partially fragmented illustration of an embodiment of an absorbent article according to the present invention.

Giant. 2 is a side view showing a partial cross-section of the absorbent article of FIG. 1.

Giant. 3 is an exploded, perspective, partially fragmented illustration of a preferred embodiment of the absorbent article of the present invention.

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Giant. 4 is a side view showing a partial cross-section of a preferred embodiment of the absorbent article of FIG. 3.

Giant. 5 is a cross-sectional view of a preferred embodiment of the backsheet aperture configuration of the absorbent article of the present invention.

Giant. 6 is a cross-sectional detail of a preferred arrangement of removable absorbent core components.

Giant. 7 is a cross-sectional view showing an alternative method of securing for a removable and replaceable component of the absorbent core of the absorbent article of the present invention.

Giant. 8 is a cross-sectional view illustrating an additional alternative method of securing for a removable and replaceable component of the absorbent core of the absorbent article of the present invention.

Giant. 9 is an exploded perspective view showing the relationship between the embodiments of the absorbent core of the present invention.

Giant. 10 is an exploded perspective view showing an embodiment of the absorbent article of the present invention.

Giant. 11 is a plan view of an absorbent core useful in the absorbent article of the present invention.

Giant. 12 is a longitudinal cross-section of the absorbent core of FIG. 11 taken along line 12-12.

Giant. 13 is an alternative embodiment of an absorbent core similar to that shown in FIG. 11 and 12.

Giant. 14 illustrates an apparatus for forming one embodiment of shaped absorbent cores according to the method of the present invention.

Giant. 15 illustrates an apparatus for forming yet another embodiment of shaped absorbent cores according to the method of the present invention.

Giant. 16 is a plan view of a relatively broad, continuous, straight line forming the structure after carving.

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Giant. 17 is a plan view of a relatively broad, continuous, straight line forming the structure after performing the first cutting operation to form the individual parts.

Giant. 18 is a plan view of separate portions of relatively wide, straight line-forming structures superimposed on relatively narrow, continuous, straight line-forming structures (strips).

Giant. 19 is a plan view of the finished shaped absorbent cores of the invention made by the method of the invention.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "absorbent core" refers to any material or combination of materials suitable for absorbing, distributing and storing aqueous liquids such as body exudates. As used herein, the term "absorbent core component" refers to one of a plurality of absorbent core components in a multi-piece absorbent core. As used herein, the term "absorbent core element" refers to one of a plurality of pieces in one absorbent core component, preferably pieces in a layered relationship. The term "absorbent article" refers to devices that absorb and contain body exudates using an absorbent core and, more particularly, relates to devices positioned against or adjacent the wearer's body to absorb and retain various body exuded exudates. A preferred embodiment of the absorbent article of the present invention is the disposable absorbent article, diaper 60, shown in FIG. 1. As used herein, the term "diaper" refers to an absorbent article generally worn by infants and incontinent persons around the lower torso of the wearer. However, it should be understood that the present invention is also applicable to other absorbent articles

• products such as incontinence pants, incontinence underwear components, diaper holders and covers, training pants, stretch diapers, feminine hygiene items such as sanitary napkins and the like.

Giant. 1 is a perspective view of parts of a partially divided representation of the absorbent core 60 of the present invention. An absorbent core 60 comprising a plurality of absorbent core components such as a central portion 50, a front panel 20, and a rear panel 30 is illustrated and described in more detail below with reference to Figs. 9. The multi-piece absorbent core 10 is also fully described in the commonly assigned, co-pending application entitled " Shaped multi-piece absorbent cores and process for their manufacture, " US patent application, serial number and grant (to be completed upon discovery). filed on (to be completed after the finding) in the name of Gerald Martin Weber, Gerald Alfred Young, Gregory Wade Taylor and Gary Dean LaVon, which is incorporated herein by reference.

By forming an absorbent core having individual (discrete) portions, several desirable results are achieved. First, the core exhibits desirable aesthetics and, when used in the absorbent article of the present invention, has a seating due to the use of discontinuous strips or portions of absorbent material. For example, the center portion may include discrete strips allowing the center portions to bend somewhat independently from the adjacent strips (and from the front and back panels) to provide better fit and comfort in the crotch area than is achieved with absorbent cores from one piece.

A second advantage of the core formed in the parts is the ability to independently vary many characteristics of the absorbent parts. These variations include measures (magnitude, intensity) of intake, • 0

• distribution, storage capacity and quantity, thickness, functionality and shape or arrangement of absorbent bands or components. For example, in a preferred embodiment of the absorbent article of the present invention, the three absorbent waistband members comprise a central portion, with one of the absorbent waistband portions having a relatively improved acquisition characteristics and the remaining two having a relatively improved acquisition / distribution characteristics.

A third benefit of the multi-piece absorbent core used in the absorbent article of the present invention is the ability to remove and / or replace the absorbent core components to regenerate the storage / redistribution capacity of the absorbent core 10. As shown in FIG. 1, discontinuity in the backsheet 62 forms an aperture 41 and provides access to absorbent core components, such as the back panel 30; thereby allowing the absorbent core components to be removed or replaced. Giant. 2 is a partial cross-sectional view of the absorbent article shown in perspective in FIG. An additional description of an exemplary disposable diaper in accordance with the present invention is given below with reference to Figs. 9.

In FIG. 1 and 2, the absorbent core 10 is shown with one layer of the central portion 50 and one layer of the front and back panels 20 and 30. Since the central portion 50 and the back panel 30 are separate absorbent members, the back panel 30 is removable from the absorbent article 60 through the opening 41. Once the backsheet 30 becomes saturated with body exudates such as urine, it can be removed and replaced with a new backsheet for continued use of the absorbent article.

As shown in FIG. 1 and 2, when the disposable diaper 60 is worn, the flap 42 may be fastened through the aperture 41 by suitable fasteners 43 such as Velcra strips or adhesive tapes (not shown). More preferably, the flaps 42 are sealed off. by releasable adhesive, thereby ensuring fluid impermeability when closed but allowing multiple opening and closing. The apertures 41 form what may be termed as some pocket or pouch with absorbent core components, for example, a back panel 30 that is removable and replaceable from that pocket. As shown in FIG. 1 and 2, to remove the back panel 30, the flap 40 is raised and the back panel 30 is removed from the absorbent article through the opening 41. Through the opening 41 through the backsheet 62, a new dry absorbent member may be inserted to replace the back panel 30. FIG. 2 shows the flap 42 in the closed position through the opening 41 corresponding to the front panel 20 (shown in FIG. 1). Overall, the front panel 20, the rear panel 30 and the corresponding apertures 41 and flaps 42 are substantially similar, but need not be so. In an alternative embodiment, it may only be desirable to include a single opening 41 and a flap 42, for example, to access the rear panel 30.

By replacing absorbent components, especially absorbent components primarily suitable for storing / redistributing fluid, use of an absorbent article such as disposable diaper 60 may be prolonged while continuing to draw moisture away from the wearer's skin. When the components of the storage / redistribution absorbent core, for example, the front panel 20 and the rear panel 30 become saturated, they may become substantially less effective in absorbing moisture from the receiving / distributing members of the central portion 50. Consequently, the middle portion 50 becomes more saturated hampered by its ability to absorb as much moisture as possible from the wearer's skin. However, once the absorbent core components such as the back panel 30 have been replaced, the absorbent core suction is regenerated and again becomes capable of absorbing moisture from the receiving / distributing components of the central portion.

Thus, the disposable diaper may be worn longer and regeneration of the absorbent core may be performed without removing the diaper from the wearer.

In a preferred embodiment of the absorbent article of the present invention, the discontinuity of continuity in the backsheet 62 forms a particular aperture, for example, aperture 44, in close proximity to the front and rear panels 20 and 30, as shown in FIG. 3 and 4. In this preferred embodiment, the backsheet pocket 45 may be attached adjacent the aperture 44. The backsheet pocket 45 serves to retain and position the front panel 20 (not shown) and back panel 30 as components formed from laminated elements, e.g. of the rear panel members 34, 35 and 36 of FIG. 4. When one backsheet element, for example, the backsheet element 34 becomes saturated body exudates, it may be removed through the aperture 41 in the backsheet and thereby expose a fresh dry backsheet element, for example, the backsheet element 35. The backsheet pocket 45 is preferably resilient and pliable, and is a substantially liquid impermeable barrier through the aperture 44, functionally becoming an extension of the backsheet 62.

The back flap 42 is reclosable and preferably resealable, and is preferably positioned such that when the flap 42 is locked in the closed position, the back panel element, for example the back panel portion 35, is forced into fluid communication with the central portion 50. FIG. 4 shows the flap 42 in a closed and sealed position through an opening 41 corresponding to the front panel 20 (shown in FIG. 20). Overall, the front panel 20, the rear panel 30 and the corresponding apertures 41 and flaps 42 are substantially similar, but need not be so. In an alternative embodiment, it may be desirable to include only one opening 41 and the flap 42 to access the rear panel 30.

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13 Giant. 5 shows preferential rendition arrangement rear parts 30 and again shows elements 34, 35 and 36

It is understood that the description expressed in the example of the back portions equally applies to the front portions 20. Removal of the back portions through the opening 41 may be facilitated by the use of pull tabs, for example a tab 46, which may be of any kind known in the art, such as a strip of plastic film adhered to each backsheet element. In addition, the backsheet elements may be separated from each other by a liquid-impermeable blocking layer 47 such that adjacent backsheet elements are not in fluid communication with each other. The blocking layer 47 may be any liquid-impermeable polymeric film, such as a film suitable for use behind the liquid-impermeable backsheet. When one element of the backsheet becomes saturated by fluid absorption from the central portion 50, it can be removed, thereby exposing a substantially dry, fresh backsheet element 35 for additional absorption from the central portion 50. In this way, the absorbent article can be refreshed or regenerated for an extended period of time without removing it from the wearer.

Giant. 6 shows a particularly preferred embodiment of the rear panel element arrangement. It is understood that the description in the expressions of the rear member elements equally applies to the front member elements. The backsheet elements 35 and 36 are shown as an example of the backsheet component 30 in a layered relationship with a liquid impermeable blocking layer 47 disposed therebetween. The blocking layer 47 is in a laminated relationship with the rear panel elements 35 and 36 and forms a liquid impermeable layer therebetween. The blocking layer portion 47 is preferably attached, for example at the attachment point 48, to the element of the lower part being removed. When the "4 * 44" element is essentially saturated, 4 • 4 4 · 4 4 «44 ·

4,444,444 44,444 444,444

4 4 · · 4 4

4444 4444 «4 44 44 44 of the rear panel, for example part 35 thereof, is pulled through the opening of the backsheet 41 by the pull tab 46, the locking layer 47 is also stretched leaving the adjacent rear panel member, for example the rear panel member 36 in position pressed into fluid communication with the central portion 50 through the opening 41.

An alternative embodiment of the front and rear panels 20 and 30 of the absorbent article of the present invention is shown in cross section in FIG. 7. Although it is shown in the expressions of the rear panel 30, it is understood that this description equally applies to the front panels 20. As shown in FIG. 7, rather than providing a backsheet for the pocket 45 attached to the backsheet, a backsheet cover 49 is provided. The backsheet 49 has a single backsheet 30 wrapped between the substantially liquid impermeable layer 54 and the substantially fluid pervious layer 55, and may be secured, for example, with suitable adhesives 39 known in the art, to the perimeter 38 of the aperture 41. The backsheet 49 is preferably removably attached such that when the backsheet 30 becomes saturated due to fluid absorption from the central portion 50, it can be removed and replaced by a fresh, dry cover 49 of the backsheet.

An alternative embodiment of the absorbent article of the present invention has a liquid impermeable backsheet without any interruptions (discontinuities) forming an opening in the backsheet. As shown in a sectional view in FIG. 8, access to removable absorbent core elements, for example, elements 34 and 35, is provided by an aperture between the topsheet 61 and the backsheet 62. As further described in more detail with reference to FIG. 10, the liquid pervious topsheet is often used in absorbent articles as the wearer contacting portion of the article. In the article of the present invention, the topsheet 61 and backsheet 62 may be separable in predetermined areas of the perimeter 55, near the waist region 63, either front, rear, or on both sides. Giant. 8 shows the topsheet and the backsheet separated in the open position. The aperture formed by separating the topsheet and the backsheet allows the absorbent core components to be removed or replaced, and is preferably resealable to provide substantially fluid impermeability. The aperture may be made resealable, for example, with a suitable adhesive 56 known in the art.

Those skilled in the art will understand additional embodiments of absorbent articles providing access to absorbent core components that do not fall within the scope of the present invention. For example, the backsheet pocket 45 may be formed integrally with the backsheet 62 by plastically deforming the backsheet 62 in the backsheet area adjacent the front and backsheets 20 and 30. Then, the backsheet may be broken by an aperture, for example, by punching (or punching) ) to allow access to the front or rear. A flap similar to flap 42 in FIG. 1, together with the fastening means 43.

In addition, it is contemplated that additional combinations of absorbent core components, elements, location and absorbency characteristics may be used with desirable functional requirements affecting the final embodiment without departing from the scope of the present invention. In particular, the absorbent core may be configured as described below.

Absorbent core

Giant. 9 is an exploded perspective view showing elements of an embodiment of the shaped absorbent core 10

4 44 444444 which can be used in the absorbent article of the present invention, for example, in a disposable diaper. As shown in FIG. 1, 3 and 11, the absorbent core 10 comprises a front panel 20 and a back panel 30, both made of absorbent material, preferably a material suitable for storing / redistributing fluid. The front portion 20 has an outer front end 21, an inner front end 22, and a pair of sides 23. Similarly, the rear portion 30 has an outer rear end 31, an inner rear end 32 and a pair of sides 33. The front portion 20 has cut areas 40 at the intersection of sides 23 and Similarly, the rear panel 30 has cut-out surfaces 40 at the intersection of the sides 33 and the internal rear end 32. The cut-out surfaces 40, or cut-out parts, connect the sides and the internal ends so that the resulting widths of the internal ends 22 and 32 are narrower. than those having outer ends 21 and 31, respectively. By " cut-off " is meant that the point of contact of the side and the ending at an overall right angle is to remove a certain amount of material from that corner and form an additional edge piece connecting the respective side and ending. The additional edge portion of the cutout 40 may be generally straight, but in a preferred embodiment it is generally arcuate, as shown in FIG. It is also contemplated that the cut-out may have generally straight sides, with a limiting example, with the result that the back or front panel is substantially trapezoid-shaped.

In a generally flat, unfolded state, the front panel 20 and the rear panel 30 are positioned such that the inner front end 22 of the front panel 20 is opposed to and spaced from the inner rear end 32 of the lower panel 30 as shown in FIG. 9-13. The distance between the front and rear can be changed as required. Overall, this distance will increase as the crotch length increases with the size of the absorbent article.

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The central portion 50 is preferably generally forming a straight line. By "generally straight line forming" is meant that the central portion preferably has a substantially constant width along its length. Generally, however, the central portion 50 only needs to span and overlap the front and rear portions 20 and 30, and may have varying width along its length. When manufactured by the method of the present invention, the central portion 50 is generally a straight line forming and extends from about the outer front end 21 of the front panel 20 to the approximately outer rear end 31 of the rear panel 30 as shown in FIG. In use, however, it is only necessary that this central portion 50 is in fluid communication with the front and rear panels 20 and 30, preferably by overlapping in relation to each other and need not extend to the outer front end 21 or the outer rear end 31.

Overall, the straight line forming center portion 50 may include a plurality of sheets of absorbent material, each having individual fluid acquisition, acquisition / distribution or storage / redistribution characteristics, as well as individual shape, width, length, and thickness characteristics. For example, in a preferred embodiment, two relatively thin, flexible polymeric foam strips 51 are made of the same storage / redistributable material as the front and back panels 20 and 30. The strips 51 and the front and back panels 20 and 30 having similar absorbent characteristics and being in liquid the connection acts as the primary storage / redistribution part.

In a preferred embodiment, the generally rectilinear strip 52 comprises a relatively thin, flexible, resilient, polymeric foam material having greater fluid acquisition or better fluid acquisition / distribution characteristics than the belts 51, thereby tending to rapidly absorb and distribute body exudates. For faster absorption into the storage / redistribution layers 51 and the front and rear portions 20 and 30.

As described by reference to FIG. 1-4, the fluid-absorbing core can be utilized in disposable products that are capable of absorbing substantial amounts of body fluids such as urine, sweat, menses and water in body solid exudates. Such articles can be manufactured in the form of disposable diapers, adult incontinence briefs, and the like. These absorbent articles generally comprise three basic structural components: a substantially liquid impervious backsheet; an absorbent core; and a substantially liquid pervious topsheet.

As shown in FIG. 10, the backsheet 62 of the absorbent article of the present invention is generally made of a substantially liquid impermeable material but is not continuous. In particular, the break in the backsheet 62 forms an aperture 41 that makes the backsheet 62 permeable to liquid in the area of the aperture 41. An adjacent backsheet 62 is disposed on the absorbent core 10, which may itself include one or more absorbent members in different layers. Adjacent to the absorbent core 10 and preferably attached to the backsheet is a liquid pervious topsheet 61. The topsheet 61 and backsheet 62 are preferably directly bonded in the periphery of the absorbent article by adhesive or other attachment means known in the art. The topsheet 61 may also be adhered to the absorbent core. It is also contemplated that the topsheet 61 may be unitary with one or more absorbent core components, thereby substantially reducing the absorbent article to two basic components: an absorbent core having an absorbent core component having an integral topsheet, and a backsheet.

Giant. 10 is an exploded perspective view of the absorbent core 10 intended to be used in a disposable disposable core.

A diaper 60 according to the present invention. However, it should be understood that the absorbent core 10 shown is also applicable to other absorbent articles such as incontinence pants, incontinence pads, training pants and the like. The diaper 60 shown in FIG. 10 is a simplified absorbent article that could represent a diaper prior to being worn on the wearer. However, it should be understood that the invention is not limited to the particular type of diaper arrangement shown in FIG. 10.

The disposable diaper 60 is shown in its flattened, uncontracted state (ie, without elastic-induced contraction, generally pulled outwardly) to more clearly illustrate the diaper assembly 60. The diaper 60 may include a substantially liquid pervious topsheet 61, a liquid substantially impermeable backsheet 62 associated with the topsheet 61, and an absorbent core 10 disposed between the topsheet 61 and the backsheet 62. Additional structural treatments such as elastic portions and fasteners for securing the diaper in place on the wearer (such as tape fasteners) may also be included. poutek).

Although the topsheet 61, the backsheet 62, and the absorbent core 10 may be assembled in a number of well known arrangements, a preferred diaper arrangement is generally described in U.S. Patent 3,860,003 (Buell), issued January 14, 1975, which is incorporated herein by reference. Preferred alternative disposable diaper arrangements herein are also described in U.S. Patent 4,808,178 to Aziz et al., Issued February 28, 1989; U.S. Patent 4,695,278 (Lawson), issued September 22, 1987; and U.S. Patent 4,816,025 (Foreman), issued March 28, 1989, all of which are incorporated herein by reference.

Giant. 10 illustrates a preferred embodiment of a diaper 60 in which the topsheet 61 and backsheet 62 are coextensive and have length and width dimensions generally greater than the absorbent core 10. The topsheet 61 is joined to and positioned above the backsheet 62 to form diaper circumference 60. This circumference defines the outer periphery of the diaper edges 60.

The topsheet 61 is soft feeling and non-irritating to the wearer's skin. Further, the topsheet 61 is liquid pervious permitting it to readily penetrate through its thickness. A suitable topsheet 61 may be manufactured from a wide variety of materials such as porous foams, reticulated foams, perforated plastic foils, natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polyester or polypropylene fibers), or a combination of natural and synthetic fibers. The topsheet 61 is preferably made of a hydrophobic material to isolate the wearer ' s skin from fluids in the absorbent core 10. A particularly preferred topsheet 61 comprises staple length polypropylene fibers having a yarn unit of 1.5 such as Hercules 151 type polypropylene sold by Hercules Inc. of Wilmington, Delaware. As used herein, the term "staple length fibers" refers to those fibers having a length of at least 15.9 mm (0.62 inches).

There are a number of manufacturing techniques that can be used to produce the topsheet 61. For example, the topsheet 61 can be woven, nonwoven, spunbonded (nonwoven), carded, and the like. A preferred topsheet is carded and thermally bonded by means well known to those skilled in the fabric manufacturing art. The topsheet 61 preferably has a weight of about 18 to 25 grams per square meter, a minimum dry tensile strength of at least about 400 grams per centimeter in the longitudinal direction (or in the moving direction of the manufacturing process). 99 9 9 9 9 9

99 99 lines), and a wet tensile strength of at least about 55 grams per centimeter in the longitudinal direction.

Although it is preferred to have the topsheet as the material closest to the wearer's skin, this is not necessary. It is contemplated that a suitable configuration of the absorbent core without a topsheet could be used and still provide desirable results such as comfort and absorbency as well as ease of manufacture and cost savings. For example, the body-facing surface of the absorbent core itself could be made of liquid-permeable, soft, conformable and non-irritating materials replacing a separate topsheet. To ensure the comfort and absorbency of the absorbent article, such an absorbent core would only need to be used in conjunction with the backsheet.

The backsheet 62 is made of a substantially liquid impermeable material and is preferably made of a thin plastic film, although other flexible liquid-permeable materials may also be used. The backsheet 62 prevents appropriate exudates absorbed and retained in the absorbent core 10 from wetting articles in contact with the diaper 60, such as sheets and undergarments. A preferred backsheet 62 is a polyethylene film having a thickness of from about 0.012 mm (0.5 mils) to about 0.051 mm (2.0 mils), although other flexible liquid impervious materials may be used. As used herein, the term flexible refers to materials that are compliant and easily conform to the overall shape and contours of the human body. The backsheet polyethylene film may also be used for flaps 42, with suitable adhesive attachment, making the backsheet of the present invention substantially impervious to liquids.

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A suitable polyethylene film is manufactured by Monsanto Chemical Corporation and is sold on the market as Film No. 8020. The backsheet 62 is preferably embossed and / or matte coated to provide a more fabric appearance. Further, the backsheet 62 may be " breathable " allowing vapor to escape from the absorbent core 10, while still preventing the exudates from passing through the backsheet 62. It is contemplated that for certain absorbent articles a highly breathable backsheet may be desirable. breathable) but substantially impervious to liquids.

The size of the backsheet 62 is dictated by the size of the absorbent core 10 and the precise diaper design selected. In a preferred embodiment, the backsheet 62 has an hourglass shape extending beyond the absorbent core 10 with a minimum distance of at least 1.3 centimeters to at least about 2.5 centimeters (about 0.5 to about 1.0 inches) around the entire periphery of the diaper. In addition, according to the present invention described in greater detail below, the backsheet has at least one aperture 41 providing access through the backsheet to a portion of the absorbent core 10.

The topsheet 61 and the backsheet 62 are joined together in any suitable manner. The term "bonded," as used herein, includes arrangements by which the topsheet 61 is directly affixed to the backsheet by attachment, and arrangements by which the topsheet is affixed to the backsheet 62 indirectly by its intermediate portions, which in turn are fastened to the backsheet 62. In a preferred embodiment, the topsheet 61 and backsheet 62 are secured to each other directly in the diaper periphery by attachment means (not shown) such as an adhesive or any other attachment means. For example, to attach the topsheet 61 to the backsheet 62 may be

44 ► 4 4 · ft

444 444 ·

44, a uniform continuous layer of adhesive or separate rows or points of adhesive are used.

Tape tab fasteners 65 are typically applied to the waist region 63 of the diaper 60, to provide fastening means for maintaining the diaper on the wearer. The tape tab fasteners 65 shown are exemplary only. The tape tab fasteners may be any of those known in the art, such as the fastening tape described in U.S. Patent No. 3,848,594 (Buell), issued November 19, 1974, which is incorporated herein by reference. These tape fasteners or other diaper fasteners are typically used near the corners of the diaper 60.

Adjacent to the periphery of the diaper 60 are disposed elastic portions 69, preferably along each longitudinal edge < 64, such that the elastic portions tend to pull and hold the diaper 60 against the wearer's legs. In addition, the elastic portions 67 may be disposed adjacent one or both waist regions 63 of the diaper 60 to secure the waist as well as or rather than the leg cuffs. For example, a suitable passport is disclosed in U.S. Patent 4,515,595 (Kievit et al.), Issued May 7, 1985, which is incorporated herein by reference. In addition, U.S. Patent 4,081,301 (Buell), issued March 28, 1978, discloses a method and apparatus suitable for producing a disposable diaper having elastically contractible elastic portions, which is incorporated herein by reference.

The elastic portions are affixed to the diaper 60 in an elastically contractible condition such that, in a normally unrestricted configuration, the elastic portions effectively retract the diaper 60. The elastic portions may be secured in the elastically contractible condition by at least two methods. For example, the elastic portions may be stretched and secured while the diaper 60 is in an unsatisfied condition. Alternatively, the diaper 60 may be retracted, for example, by pleating and the elastic portion fastened and attached to the diaper 60.

• · · · «· · ··· ·· <

While the elastic portions are in their non-relaxed or unstretched condition. The elastic portions may extend along a portion of the length of the diaper 60. Alternatively, the elastic portions may extend the entire length of the diaper 60, or any other length suitable to provide an elastically contractible line. The length of the elastic portions is dictated by the diaper design.

In use, the diaper 60 is mounted on the wearer by placing one waist region below the wearer's back and extending the remainder of the diaper 60 between the legs of the wearer so that the other waist region is positioned over the front of the wearer. The strap tab 65 or other fasteners are then preferably attached to the outwardly facing surfaces of the diaper 60, as shown, for example, in FIG. 14. In use, disposable diapers or other absorbent articles of the present invention tend to distribute and store fluids more rapidly and more efficiently and remain dry due to the high absorbent capacity of the fluid-absorbing components. Disposable diapers with incorporated fluid absorbing components of the invention may also be thinner and more flexible.

When used as an absorbent core in a disposable diaper 60, a preferred embodiment of the core 10 of the present invention is positioned such that the acquisition / distribution web 52 is in fluid communication with the topsheet 61, and serves to rapidly receive and distribute body exudates from the wearer &apos; generally, a plurality of absorbent storage / subdividing belts 51 and front and rear panels 20 and 30. The front panel 20 generally corresponds to the portion of the disposable diaper worn at the front of the wearer, with an outer front end 21 that is generally adjacent the waist area of the wearer. Similarly, the back panel 30 corresponds to the portion of the disposable diaper worn in the back of the wearer, with the outer rear end 31 that is generally adjacent the waist surface of the wearer. Overall, the straight center portion 50 has a width 53 corresponding

9

9

99,999,999

9 9 9

99 99 suitable for the crotch area 66 of a disposable diaper. Also, the length of the generally straight line forming center portion 50 may be varied to provide appropriate fit for wearers of different sizes.

Giant. 11 is a plan view of a shaped absorbent core 10 as anticipated by one useful embodiment in the absorbent article of the present invention. As shown, the front and rear panels 20 and 30 together with the generally straight central portion 50 form an overall elongated hourglass shape suitable for use in a disposable diaper or similar absorbent article. In a preferred embodiment, the width 53 of the generally rectilinear portion 50 is suitable for comfortable fit within the crotch area of the wearer when the absorbent core 10 is incorporated into an absorbent article such as a disposable diaper.

The amount and location of the strips 51 or 52 of the overall straight center portion 50 may be varied to achieve desirable characteristics such as thinness, softness, flexibility, or beneficial magnitude of fluid acquisition, distribution and storage. For example, FIG. 12 illustrates a cross-section of an embodiment of the present invention using one receiving / distributing belt 52 and one storage / redistribution belt 51, both positioned over the front and rear storage / redistribution portions 20 and 30, resulting in a thin, flexible absorbent core 10. The term "over" means that side of the absorbent core of the invention corresponding to the body of the wearer when used in an absorbent article such as a disposable diaper.

The plurality of layers of the front and back panels 20 or 30 may also be varied to achieve desirable characteristics such as beneficial sizes of fluid acquisition and distribution, as well as fluid storage capacity and amount and wearer comfort. If more than one absorbent layer is used in the front and / or rear panels

0 ·

0 0

000 ·· «

0

00

• 0 • 0

These parts will hereinafter be referred to as parts and the individual layers will be referred to herein as elements. For example, FIG. 13 is a cross-sectional view of an additional embodiment corresponding to the overall plan view of FIG. 11. FIG. 13 shows two elements (layers) of the front and rear panels 20 and 30, corresponding, for example, to the rear panel elements 34 and 35 shown in FIG. 4. As shown in FIG. 13, both rear panel members may be located below the center portion 50. As described above with reference to FIG. 5 and 6, the front or back panel may be separated by a liquid impermeable material with beneficial results.

In summary, the absorbent core 10 comprises a plurality of discrete components, each of which is capable of having different fluid acquisition, acquisition / distribution, or storage / redistribution characteristics. In the context of the present invention, it should be noted that the term "liquid" means "liquid." If the fluid acquisition, acquisition / distribution, and storage / redistribution components are in fluid communication with each other, they may be positioned relative to each other in a wide variety of configurations. Exemplary materials for use with the present invention will be described in more detail below.

Absorbent core materials

As described above, the absorbent core 10 comprises a plurality of discrete components, each of which may comprise discrete elements that are each capable of having different fluid acquisition, acquisition / distribution, or storage / redistribution characteristics. The respective components or elements thereof may be made of any absorbent

9 9 • 9 9 9

9

9

9

9999 99 99 ··· material or combination of materials having sufficient structural integrity to be treated as a single unit. Typical materials known in the art such as fibrous nonwoven materials, fibrous wet laid materials, and combinations of fibrous materials having absorbent gelling materials dispersed therein or within their fibrous structure may be used. If necessary, these fibrous nonwoven materials may be formed into any bag of material substantially encased in a liquid-permeable structure that provides structural integrity for removal and replacement into the article of the present invention.

Particularly preferred absorbent materials for use as absorbent members are those which are foam-based in nature. Polymer foams that are suitable for use in a fluid receiving component can generally be characterized as structures that arise when relatively monomer-free gas or relatively monomer-free liquid are dispersed as bubbles in a polymerizable monomer containing liquid, followed by polymerization of polymerizable monomers into a liquid-containing monomer, that surrounds the bubbles. The resulting polymerized dispersion may be in the form of a porous solidified structure that is the aggregate of cells whose edges or walls contain a rigid polymerized material. These cells themselves contain a relatively monomer-free gas or a relatively monomer-free liquid that has formed bubbles in the liquid prior to polymerization.

Particularly suitable absorbent foams for absorbent articles such as diapers are made from High Internal Phase Emulsions, hereinafter referred to as "HIPEs". See. for example, U.S. Patent 5,260,345, issued to DesMaraise et al. on November 9, 1993; and U.S. Pat. No. 5,268

999 •

4 4 9 9 9 9

9

9999 9 9999

226, issued to DesMaraise et al. on December 7, 1993; and U.S. Patent 5,563,179, assigned to Stone et al. on October 18, 1996; all of which are incorporated herein by reference. These HIPE absorbent foams provide desirable fluid management properties, including: (a) relatively good uptake rates (sizes) for rapid uptake of urine outflows; (b) relatively good leakage and distribution characteristics for transferring soaked urine or other body fluids away from the initial impact zone and into the unused portion of the foam structure to allow the successive fluid ejections to be received; and (c) a relatively high storage capacity with a relatively high fluid capacity under load, i.e., under compressive forces.

The HIPE absorbent foams are also flexible and soft enough to provide the wearer of the absorbent article with a high degree of comfort, some of which may be made relatively thin until subsequently moistened with absorbed body fluid. See. also the aforementioned U.S. Pat. No. 3,445 to Young et al., and U.S. Pat. on June 7, 1994, which discloses absorbent cores having a fluid acquisition / distribution component which may be a hydrophilic, flexible, open cellular foam such as melamine-formaldehyde foam (e.g. BASOTECT ^(R) manufactured by BASF) and a storage / redistribution component by which is an HIPE based absorbent foam.

Exemplary materials suitable for use with the present invention are not limited to HIPE foams and will now be described in more detail.

Receiving component

One part of the absorbent core is a liquid acquisition component that includes a porous absorbent structure having a 9, 9, and 9 absorbent structure. 9 9 9 • 9 9 99 999

9 9 9

99 99 certain fluid handling characteristics with respect to excreted aqueous body fluids, such as urine, passing on and into the structure, for example, through the topsheet of an absorbent article as described above. Because such fluid is often excreted in sprains, the receiving component must be able to rapidly receive, temporarily retain and also preferentially transfer (or distribute) the liquid, for example, by wicking or other mechanisms, from the point of initial fluid contact to other parts of the receiving component for finally being absorbed into adjacent fluid receiving / distributing parts or storage / fluid distributing parts.

Any porous absorbent material may be used as the acquisition layer 52 to soak up and distribute aqueous body fluids into the fluid acquisition / distribution components or storage / fluid distribution components of the core. One measure of the fluid uptake efficiency of a particular absorbent material used to form a particular receiving component is the amount (or rate) of fluid uptake, which measurements are taken for the time required to absorb the amount (s) used in the synthetic urine test. its internal structure. Appropriate measures of fluid uptake and methods of testing are generally described in the above-mentioned Young et al. ^ 345. Accordingly, the fluid acquisition component should be formed of an absorbent material having an initial absorption rate of at least about 2 mL of synthetic urine per second. More preferably, the fluid acquisition component will comprise an absorbent material having an initial absorption rate of at least about 6 mL of synthetic urine per second. “The initial amount of fluid uptake is the time it takes for the first dose of such fluid

to be absorbed into the absorbent material before the absorbent material retains any test fluid in the synthetic urine.

Preferred absorbent materials for the receiving member include non-woven synthetic fiber materials, cellulosic nonwoven materials, and various synthetic / cellulosic nonwoven materials. A preferred synthetic nonwoven material is that disclosed in commonly assigned U.S. Patent No. 4,998,345 to Reising, issued January 29, 1991; and U.S. Patent No. 4,988,344 to Reising, issued January 29, 1991, both of which are incorporated herein by reference. The reising acquisition layer comprises a first layer of hydrophilic fibrous material with a lower average density than other portions of the first layer, so that it rapidly absorbs exuded fluids.

A preferred cellulosic nonwoven material suitable for receiving core components is formed of cellulosic fibers which impart dry structure characteristics and density to the absorbent core components. More specifically, parts or regions of the absorbent core that receive secreted body fluids will preferably have an average dry density of less than about 0.30 g / cc and an average wetting density of 1% aqueous NaCL less than about 0.20 g / cc, and an average dry basis weight of from about 0.001 to about 0.10 g / cm ² . Preferred cellulosic nonwoven materials also include from about 50% to 100% chemically stiffened, twisted and curled cellulosic fibers and from about 0% to about 50% binder compositions. Such a cellulosic nonwoven is disclosed in the above mentioned patent ^Σ 345 Young, and commonly assigned U.S. Pat. No. 5,531,728 to Lash, issued July 2, 1996, which is hereby incorporated by reference.

• · · · · · · · · · · · · · · · · · · · · · · · · · ·

The acquisition layer may be comprised of several different materials comprising polyester, polypropylene or polyethylene-containing synthetic fiber structures, natural fibers containing cotton or cellulose, mixtures of these fibers, or any equivalent materials or combinations thereof. Examples of such receiving materials are described in more detail in U.S. Patent No. 4,950,264 (Osborn), issued August 21, 1990, which is hereby incorporated by reference. Cellulosic fibers, in addition to being chemically stiffened, may also advantageously be combined with high surface area fibers such as eucalyptus fibers as described in commonly assigned and co-pending U.S. patent application Ser. No. 08 / 686,076, Seger et al., Filed Jul. 24, 1996, the contents of which are hereby incorporated by reference. The chemically stiffened fibers and eucalyptus fibers may be co-formed in a layered manner with thermoplastic binder means or chemical binder means as disclosed in the above-mentioned Seger patent application.

Preferred thermoplastic binder compositions comprising preferred thermoplastic fibers are described in commonly assigned U.S. Patent No. 5,549,589 to Horney et al., Issued August 27, 1996, which is hereby incorporated by reference. The thermoplastic binder compositions may comprise any hot melt adhesives which can be melted at temperatures that do not substantially damage the cellulose fibers. Once thermally applied, the resulting nonwoven material exhibits dry / wet mechanical properties such as flexibility, flexibility, and structural integrity such that they can be processed as a cylindrical blank by the method of the present invention.

If binding agents are used to impart structural integrity to the nonwoven structure, the absorbent portion will preferably comprise between about 80% and about 95% of chemically stiffened fibers. from about 3% to about 20% of the high surface area fibers and from about 0% to about 5% of the binder chemical additive. A currently preferred chemical additive binder is commercially available polyacrylamido-glyoxal resin, sold by Cytex Industries, West Patterson, N.J. under the trade name Parez ™ 631 NC. Additional suitable fiber types and chemical additive binder compositions are discussed in commonly assigned S.N. No. 08 / 633,630 (Serger et al.), Filed April 17, 1996, the contents of which are hereby incorporated by reference.

Other receiving materials may be made by wet laying, in accordance with commonly assigned U.S. Patent No. 5,217,445 to Young et al., Issued June 8, 1993, which is hereby incorporated by reference. Generally, the wet process of the laid structure can be produced by depositing an aqueous slurry of fibers on a laminated wire mesh, dewatering the wet laid slurry to form a wet structure, and drying the wet structure. A further description of specific wet-laying techniques suitable for forming the receiving core component for a suitable use in the present invention is provided in the aforementioned Young ^I 345 patent. In addition to the rapid uptake of body fluids, the absorbent receiving components of the invention of fluids effectively for the benefit of other fluid acquisition / distribution components or storage / fluid redistributable components comprising foam-based storage components. Absorbent foams suitable for use as a receiving component of the present invention combine relatively high capillary absorption pressures and properties of their capacity to weight (as compared to traditional foams). Such foams are described in U.S. Patent No. 5,550 ·· ··

I · «« 1 · 4 · 4

167, issued to Des Marais et al. on August 27, 1996, which is hereby incorporated by reference.

Fluid acquisition / distribution components

Fluid acquisition / distribution components may include materials similar to the receiving component, with multiple distribution characteristics. Since the excreted body fluid, such as urine, is often excreted excretely, the fluid acquisition / distribution component must be capable of rapid acquisition and must also preferably transfer fluid, e.g., by leakage or other mechanisms, from the fluid contact point to other portions of the fluid receiving / distributing member. final absorption into an adjacent fluid storage / redistribution portion. Such materials are preferably polymeric foam materials having a greater degree of partitioning ability, so that body exudates can be transferred more efficiently from the acquisition zone to the storage components of the absorbent core.

The absorbent materials herein comprising the fluid acquisition / distribution component of the articles will preferably be reasonably effective in transferring the absorbed fluid from one portion or region of the fluid acquisition / distribution component to another. This fluid transfer often results from the inherent tendency of the absorbent material of the acquisition / distribution member to leak fluid through its structure. Accordingly, one measurement of the fluid distribution efficiency of the absorbent material used to form the acquisition / distribution component relates to the ability of the absorbent material to perpendicularly absorb artificial urine.

The efficiency of vertical leakage can be measured and quantitatively expressed in a number of ways, but in one way, but in one way or another. A typical indicator of perpendicular leakage performance is the height at which the test strip of absorbent material perpendicularly penetrates synthetic urine from the reservoir over a period of time. For purposes of this invention, this height, termed "vertical wicking height, determined as described in the aforementioned patent ^and 345 Young et al. The fluid acquisition / distribution component herein will preferably be formed of an absorbent material having a perpendicular leak height of at least about 5 cm after 30 minutes. More preferably, the fluid collection / distribution component will comprise an absorbent material having a perpendicular leak height of at least about 10 cm after 30 minutes, and most preferably an absorbent material having a perpendicular leak height of 25 cm.

Any porous absorbent material may be utilized to soak and distribute aqueous body fluids within the range set forth herein in terms of fluid acquisition rate and preferably vertical wicking height as or as part of the fluid acquisition / distribution component of the absorbent articles herein. Often, such absorbent material may be substantially foam-based and / or fiber-based.

A preferred embodiment utilizes an open-celled polymeric foam material which, in addition to functioning as part of the acquisition / distribution within the absorbent core, has improved desorption properties allowing other core components having higher absorption pressures than the desorption pressure of the acquisition / distribution foam to further distribute the fluid. Especially useful as or in the fluid acquisition / distribution components are those absorbent foams having a pore volume of from about 2 to 100 mL / g, a capillary suction specific surface area of from about 0.2 to 1 m ² / g; bubble size (cellular structure, cells, cells) from about 10 to about 300 microns and density from about

0.01 to 0.5 g / cm ³ , provided that the values of these parameters are chosen such that the absorbent foams exceed the aforementioned minimum vertical leakage size. Relevant terms (or concepts, pos. Translator's.) Of foam flexibility, hydrophilicity, pore volume, capillary suction, specific surface area, the bubble size and density as relate to the present invention are more fully described in the aforesaid patent ^r 345 Young et al . Absorbent polymeric foam materials having an open cellular structure suitable for use as a fluid acquisition / distribution component in the present invention are described in the aforementioned U.S. Pat. No. 79 (Stone et al.).

Other types of nonwoven webs suitable for use as part of fluid acquisition / distribution include structures such as surfactant treated, bonded carded webs, blown fused synthetic macrofibers or microfibers, cellulosic co-formed structures, co-formed structures staple fibers and the like. If nonwoven fibrous absorbent structures are used in the present invention, these structures will preferably be composed of substantially hydrophilic, chemically stiffened cellulosic fibers. These cellulosic fibers are typically wood pulp fibers that have been stiffened with an inter-fibrous, chemical stiffening agent and otherwise processed to be formed into twisted, curled arrangements, as discussed in detail in the aforementioned patents * 345 of Young et al. and Lash, as in Seger ^T 630.

Storage / fluid redistribution components

An absorbent core suitable for use with the present invention comprises at least one and preferably two separate absorbent cores.

4,444 4444 • 4,444 4 · 444444

4 4 4 4 4 ·

44444444 444 44 44 44 storage / fluid redistribution components. These storage / fluid distribution components function to retain body exudates from the wearer &apos; s body, leaving the wearer feeling dry and preventing leakage. The storage / fluid redistribution components are maintained in fluid communication with the acquisition or acquisition / distribution layer (brew) so that urine or other aqueous body fluids present in the acquisition / distribution component can be desorbed by being absorbed by the storage / fluid redistribution component (s). ).

Fiber nonwoven materials as described above may be useful as the storage / liquid redistributable component (i), especially when bonded (combined) to particles of substantially water-insoluble, absorbent, hydrogel-forming polymeric materials. Particularly useful are nonwoven materials comprising absorbent gelling materials such as those described in U.S. Patent No. 5,061,259 to Goldman et al., Issued October 29, 1991; as described in U.S. Patent 4,654,039 to Brandt et al., issued March 31, 1987 (re-granted April 19, 1988 as Case 32,649); U.S. Patent 4,666,983 (Tsubakimoto et al.), issued May 19, 1987; and U.S. Patent 4,625,001 (Tsubakimoto et al.), issued November 25, 1986; all of which are incorporated herein by reference; // absorbent macrostructures manufactured from those absorbent gelling materials such as those described in U.S. Patent 5,102,597 (Roe et al.), issued April 7, 1992; and in U.S. Patent No. 5,324,561 to Rezai et al

June 23, 1994; both of which are incorporated herein by reference; // absorbent gelling materials laminated between two tissue layers such as those described in U.S. Patent 4,260,443 (Lindsay et al.), issued April 7, 1981; U.S. Patent 4,467,012, Pedersen et al., issued Aug. 21, 1984; in US Patent 4,715,918 (Lang • 0 • 0 0 0 0 «·« «0 0 0 0 • 0 0

et al., issued December 29, 1987; U.S. Patent No. 4,773,903 to Weisman et al., issued September 27, 1988; in U.S. Patent 4,851

069 (Packard et al. ) granted July 25th 1989; in patent No. 4,923,454 (Seymour et al.), granted 8. May 1990; in U.S. Patent 4 950 264 (Osborn), granted 21. August 1990; in U.S. Patent 4 994 037 1, granted on 19 . February 1991; in U.S. Patent 5 009 650 ( Bernardin) i, granted 23 . April 1991; in U.S. Patent 5 009 653 (Osborn), granted 23. April 1991; in U.S. Patent 5 128 082 (Makoui), granted on July 7 1992; in U.S. Patent 5 149 335 (Kellenberger et al.) , awarded 22. September 1992; and in the patent US 5,176 668 (Bernardin), granted 5.

January 1993; all of which are incorporated herein by reference.

A preferred storage / liquid redistributable member of the absorbent core comprises cohesive layers made of particles of substantially water-insoluble, absorbent, hydrogel-forming polymeric materials. The layers may be produced by laying predetermined amounts of hydrogel-forming materials with crosslinking agents and curing. A preferred material of this type is described in commonly assigned U.S. Patent No. 5,324,561 to Rezai et al., Issued June 28, 1994, which is hereby incorporated by reference.

The most preferred storage / fluid redistributable component materials include composite polymeric foam materials that, upon contact with aqueous fluids (especially aqueous body fluids such as urine), can expand and absorb these fluids. These absorbent polymeric foam materials include a hydrophilic, flexible, nonionic polymeric foam structure of interconnected open cells as disclosed in U.S. Patent No. 5,387,207 to Dyer et al. On February 7, 1995, and co-pending S.N. 08/563 866, entitled

4 · · * 4 4 ·· ·· • 444 «4 * 4 4 4 4 4 • 4 4 4 4 4 4 4 4 • 4 4 44 44 444444 4 4 4 · 4 4 4

44444444 444 44 44 44 "Absorbent foam materials for aqueous liquids made from high internal phase emulsions having very high water to oil ratios", DesMarais et al., Filed Nov. 29, 1995; both incorporated herein by reference. Other suitable polymeric absorbent foam materials, material characteristics, and characteristic tests are described and reported in the aforementioned ^T 345 Young et al. Patent.

Polymeric foam materials suitable for use as a fluid storage / redistribution component in an article of the invention should have high capillary absorption pressures, also known as capillary suction, to effectively desorb adjacent adjacent acquisition / acquisition / distribution components. Pressure Capillary absorption can be measured using a vertical wicking capacity test as described in detail in the TEST METHODS section of the aforementioned patent ^Σ 207 Dyer et al. The vertical leakage capacity test data provides a curve from which the capillary absorption pressure is determined. Preferred absorbent foams for use in the product of the present invention have capillary absorption pressures of from about 3 to about 20 cm. Particularly preferred absorbent foams have capillary absorption pressures of from about 3 to about 15 cm.

The storage / liquid redistributable component of the composite polymeric foam of the present invention may utilize low density absorbent foams (when stretched). For a given stretched thickness, the lower density foams in their folded state are thinner than previous HIPE absorbent foams. These low density foams utilize a more efficient polymeric material and, as a result, provide economically attractive means of achieving thinner absorbent cores for absorbent articles such as diapers, stretch training pants, adult incontinence briefs, sanitary napkins, and the like. This is achieved at • «• 9

At the same time maintaining the desirable ability to absorb liquids, dryness and mechanical properties.

Method and apparatus for producing shaped absorbent cores

A preferred method of making a shaped absorbent core suitable for use with the present invention is now described by reference to Figs. 14-19. Giant. 14 illustrates an exemplary apparatus 70 suitable for performing a method of forming the absorbent core components of a preferred embodiment of the present invention as shown in FIG. 1. The method shown in FIG. 14 and described in detail below may be readily adapted to produce absorbent cores comprising various combinations and locations of absorbent portions such as those shown in FIG. 12 and 13. Exemplary modifications are illustrated in FIG. 15 and, unless otherwise stated, can be understood by reference to the description of the method of FIG. 14, since the same numerals indicate similar (same) parts. The method of the invention is not limited to nonwoven web materials or absorbent polymeric foam materials, but is suitable for use with any total absorbent material formed into structures, whether woven or nonwoven, fibrous or polymeric, as known in the art that can be supplied on a cylindrical blank and have sufficient integrity for processing according to the method of the present invention.

The first, substantially narrow, straight line forming web 81 is unwound from the feed roll 71. The web 81 has a width generally corresponding to the width 53 of the generally rectilinear center portion 50, as shown in FIG. 1, 3, 9 and 10. The structure 81 comprises a material suitable for use as a acquisition / distribution layer 52 of a preferred embodiment,

9

9 99 99 99

999 9 9 9 9 9

9 9 9 9 9

9 9 99 99 999999

9 9 9 9 9 9 as shown in FIG. 9 and 10. The structure 81 is guided by an entry point 100 onto a conveyor 102 where it is located for further processing as described below.

In a preferred embodiment, the second and third relatively narrow straight lines (webs) 82 and 83, composed of a material suitable for receiving / distributing or storing / redistributing fluid, are unwound from the supply rollers 72 and 73. Structures 82 and 83 correspond to the storage / liquid redistribution layers 51 in FIG. 9 and 10 and may have a width generally corresponding to the width 53 of the central portion 50. The structures 82 and 83 are guided by an entry point 100 onto a conveyor 102 where they are placed in layers on the structure 81 for further processing as described below.

A relatively wide, continuous straight structure 84 of absorbent material having a longitudinal axis and lateral portions is unwound from the supply roll 74. In a preferred embodiment, the structure 84 is suitable for use as a storage / fluid redistributing portion of the absorbent core 10 and has a width suitable for forming. the front panel 20 and the rear panel 30 shown in FIG. 1, 3, 9 and 10. The side portions of the structure 84 generally correspond to the sides 23 and 33 shown in FIG. 11.

The structure 84 is guided from the roller 74 to a cutting device 90. The cutting device 90 preferably includes two nip rollers 91 and 92, between which a structure 84 is supplied. When the structure 84 is supplied through the nip 90 of the rollers 91 and 92, the cutting blades (not shown) on the roll 91 cut out substantially arcuate portions from opposite sides of the structure 84, so that when the structure 84 leaves the cutting device 90, it appears as shown in FIG. 16. FIG. 16 shows a continuous, straight line forming structure 84 with substantially arcuate cut-outs 120 spaced apart from each other.

9

99 gaps 121 corresponding to the location of the cutting blades on the roller 91 shown in FIG. 14.

The continuous rectilinear structure 84, cut as shown in FIG. 16, it is further supplied to the first chute and cut assembly 95 for making cross-sections to the longitudinal axis that break (divide) the rectilinear (flat) structure 84 into individual portions 85 and separate these separate portions as shown in FIG. The structure 84 is guided to a rotating drum 96 which serves as a pressure plate. Once in contact with the surface of the rotary drum 96 and prior to cutting into individual portions, the structure 84 moves at a speed less than the surface of the drum and slides relative to the surface of the drum 96 under slight vacuum applied through holes in the surface of the drum. Once the structure 84 is cut into the individual portions 85, a slightly higher vacuum is applied so that the separate portions 85 remain in contact with the rotary drum 96, moving at the same speed as the drum surface in the spacing apart. The cutting roller 97 rotates in accordance with the rotating drum 96, the diameter of the cutting roller 97 is such that the cutting blade 98 attached to the cutting roller interrupts the rectilinear structure 84 in the spaced apart gaps 121 in FIG. 16, forming the individual portions 85. As shown in FIG. 17, the individual portions 85 may best be described as being generally rectangular in shape with the corners 40 cut out corresponding to the slits 40 in FIG. 11.

The rotating drum 96 is positioned such that during rotation, the individual portion 85 is brought into contact with the layer 83 moving on the conveyor 102. The vacuum arrangement (device) in the rotary drum 96 is such that in the position of contact with the layer 83 the individual portion 85 is released from the rotary drum 96 and continues to be supported on the layer 83 by the conveyor 102.

9 9

···· 9999

The linear speed of the conveyor 102 is generally equal to the tangential linear speed of the rotary drum 96 so that the individual portions 85 are deposited on the layer 83 in a spaced relationship as shown in FIG. 18.

Giant. 18 is a plan view of the material that is supported by the conveyor 102 at, for example, point 103 of FIG. The layer 83 and the layers 82 and 81 below (not shown) form a continuous straight line forming structure (strip) below separate portions 85 spaced apart from one another. The individual portions 85 are spaced apart from one another at distances 130 corresponding to the overall distances between the transverse centerlines 131 of the adjacent individual portions 85.

The material carried on the conveyor 102 is fed to a second chute and cutting assembly 150 for making cross-sections that break all layers of material. The cutting roller 152 has a diameter corresponding to the overall distance between the transverse centerlines 131 of the individual portions 85, as shown in FIG. 18. The roller 151 serves as a pressure plate for the cutting blade 153 attached to the cutting roller 152. The cutting blade 153 completely splits the layers at or near the transverse middle ages 131 of the individual parts 85. After leaving the second chute and cutting assembly 150, the absorbent material is formed into individual absorbent cores. 10 of the present invention. A variety of known methods can be used to separate the individual absorbent cores 10, such as varying the relative speeds of the conveyors 102 and 160. The individual absorbent cores 10 are carried by the conveyor 160 for further processing into absorbent articles, if necessary, and are seen on the conveyor 160 in plan view as shown in FIG. 19 Dec

As shown in FIG. 19, it is not necessary for the length of the front piece 20 measured from the outer front end 21 to be 0 · 0

0 0 0 0 • 0 «·· • 0 00 · ··· · 00 00 ·· • 00

to the inner front end 22 equal to the length of the rear end 30, measured from the outer rear end 31 to the inner rear end 32. The position of the laminate on the conveyor 102 relative to the second sliding and cutting assembly 150 determines the relative lengths of the front end 20 and the rear end 30. a preferred embodiment of the present invention is the rear panel 30 longer than the front panel 20 as shown in FIG. Such an arrangement itself provides a better fit when the absorbent core 10 is used as a disposable diaper.

As shown in FIG. 14 and 15, the gap length 130 may be varied to produce the desired length of the generally straight center portion 50. It is desirable to be able to vary the length of the center portion 50 of the absorbent core 10 for use in disposable diapers to accommodate the size difference of infants or adults using such diapers. .

Giant. 15 depicts an embodiment of a method and apparatus as it may be to manufacture the core shown in FIG. Rather than the third relatively narrow straight structure 83 (or its web) unwound from the supply roll 73, the relatively narrow straight line forming structure 86 is unwound from the supply roll 76. The structure 86 is then guided to form an upper layer of absorbent material on the conveyor 102. This method continues as described above to form the absorbent core shown in FIG. 5.

Giant. 15 illustrates an exemplary method for forming an absorbent core 10 of the invention as shown in FIG. 13. In this embodiment, an additional, relatively broad, continuous straight line forming structure 87 of absorbent material having longitudinal axis and side portions is unwound from the supply roll 77 and is contacted and aligned with structure 84 prior to entering the cutting device 90. Structures 84 and 87 may be adhered to each other by known methods

0

0 0 0 0 0 0 • 0 0 0 0

0 0 · 0

0 000 000

0 0

00 00 to facilitate proper alignment during the remainder of the process, especially after processing by sliding and cutting assembly 95 of the material.

The method described provides a number of significant advantages. For example, this method generates considerably less waste than a typical one-piece molded absorbent core process. This method also ensures efficient delivery of the structures (strips) of absorbent materials from the cylindrical blank, especially the foam, from which the parts and the straight line forming the strips are made. One advantage of such a process is the longer life or service life of the roll of the supplied structure. For example, the narrower structures (strips) of absorbent material used to produce a straight line of formed strips may be wound on a template (bobbin) for a considerably longer roll life. A third advantage of the present invention is better control of certain processing value variables such as the placement of core components in proper functional relationships. For example, since the wider structure of the absorbent material is carved and interrupted at the point where the front and back panels are made, it is much easier to conceal the carved / detached panels in correlation with the narrower straight-line formed band (s) to produce the composite absorbent core.

Although particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is intended in the appended claims to cover all such changes and modifications within the scope of the present invention.

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9 9

9

Claims (10)

PATENT CLAIMS PV - ty • 9 99 99 ⁹ 9 9 9 9 9 9 9 9 9 9 · 99 999 999 9 99 99 99 An absorbent article for receiving a body fluid of a wearer comprising a backsheet and comprising: (a) at least one, preferably at least two, removable absorbent core components disposed adjacent the backsheet, and (b) a backsheet comprising means for providing access to the removable absorbent core components by the backsheet, such removable absorbent core components may be of the absorbent core. product removed by the lower layer. The absorbent article of claim 1, further comprising a backsheet comprising a substantially liquid impermeable material, and the access means comprises a portion of the backsheet that is liquid pervious so that the liquid pervious portion defines an aperture adjacent the removable absorbent member. core. The absorbent article of claim 1 or 2, further characterized in that the removable absorbent core components comprise a nonwoven fibrous material, preferably in association with absorbent gelling materials. The absorbent article of any of the preceding claims, further characterized in that the removable absorbent core components comprise a polymeric foam material with an open cellular structure. 9 9 9 9 The absorbent article of any of the preceding claims, further characterized in that the removable absorbent core components exhibit absorption pressures (derived from a vertical wicking height over a 30 minute period) of from 3 to 20 cm, and preferably from 3 to 15 cm. An absorbent article for receiving body fluids of a wearer having a backsheet, anterior waist region, a back waist region, a crotch region, and an absorbent core disposed between the backsheet and the wearer, the absorbent core being characterized by: (a) at least one first absorbent core component disposed in the crotch region, the first absorbent core component preferably comprising at least two first absorbent core elements in fluid communication in a layered relationship; (b) at least a second barrel of the absorbent core, the second barrel preferably comprising at least two second element of the absorbent core in a layered relationship, each second element of the absorbent core preferably being independently removable, the second element of the absorbent core being removably disposed in fluid communication with a first absorbent core component; and (c) a backsheet comprising means for providing access to the second absorbent member of the absorbent core through the backsheet, such that the second absorbent core member or second absorbent member elements may be removed from the absorbent article by the backsheet. • 9 0 · 99 99 9 9 999 999 9 9 99 99 The absorbent article of claim 6, further comprising a removable absorbent core comprising at least one liquid impermeable blocking layer disposed between the removable absorbent core elements, each liquid impermeable blocking layer being preferably attached to one removable absorbent core element, such that each the impermeable blocking layer is removable with a removable absorbent core element attached thereto. An absorbent article according to claim 6 or 7, further characterized in that the first absorbent core component comprises a fibrous nonwoven material, preferably in association with an open-celled polymeric foam material, and more preferably in association with absorbent gelling materials. The absorbent article of claims 6 to 8, further characterized in that the second absorbent core component comprises a polymeric foam material with an open cellular structure, preferably in association with a fibrous nonwoven material, and more preferably in conjunction with absorbent gelling materials. An absorbent article for receiving body fluids comprising a topsheet and a backsheet attached peripherally to the topsheet, said absorbent article having: (a) at least one removable absorbent core member disposed between the topsheet and the backsheet; and 44 44 • 4 «· 4 4 4 »• 44 44 44 • 4 4 · 4 4 4 4 4 4 4 4 4 44 444 444 4 4 4 4 4 444 44 44 44 (b) a topsheet and a backsheet that are separable in predetermined areas of said perimeter, such that the removable absorbent core member can be removed from the absorbent article. 9 9 • 9 9 9 9 9 9 9 WO 98/43574 1/12 γν stM 99 99 99 99 99 9 · 9 9 9 9 9