MXPA99008882A - Absorbent articles having removable components - Google Patents

Abstract

The present invention relates to absorbent articles suitable for absorbing and retaining aqueous body fluids. Absorbent articles of the present invention comprise a discontinuous, substantially fluid impervious backsheet and an absorbent core disposed between the topsheet and the backsheet. The absorbent core comprises a plurality of core components which are removable, with access for removalprovided by at least one discontinuity forming an opening in the backsheet. Once removed, other absorbent core components or layers of components may remain in the absorbent article. Also, additional absorbent core components or layers may be added through the opening in the backsheet. In a preferred embodiment the absorbent core comprises a plurality of components, including at least a front panel, a rear panel and a center section. Each of the absorbent components may include layers of absorbent members. Upon saturation with bodily discharges certain components or members of the absorbent core may be removed from the absorbent article through the backsheet. New, unsaturated absorbent components or members may then be positioned in place of the removed saturated components or members, or, more preferably, upon removal of the saturated component or member, an additional unused component or member may remain in position for use.

Description

ABSORBENT ITEMS THAT HAVE REMOVABLE COMPONENTS FIELD OF THE INVENTION The present invention relates to absorbent articles, such as disposable diapers. This invention also relates to absorbent articles having multiple piece absorbent cores.

BACKGROUND OF THE INVENTION Absorbent articles such as disposable diapers, incontinence pads, training pants, and catamenial towels generally include an absorbent core for receiving and maintaining body exudates. The absorbent core typically includes a fibrous web, which may be a non-woven web, placed with air, of natural or synthetic fibers, or combinations thereof. The fibrous webs used in these absorbent articles often also include certain gelling absorbent materials commonly referred to as "hydrogels," "super absorbent," or "hydrocolloid" materials for storing large amounts of the discharged body fluids. These materials absorb through capillary or osmotic forces, or a combination of both. Alternate absorbent materials capable of providing capillary transport of the fluid are open cell polymeric foams. If done properly, open cell polymeric foams provide capillary acquisition, transport and storage characteristics of the fluid required for use in high performance absorbent cores for absorbent articles such as diapers. Absorbent articles containing these foams may also possess desired wet integrity, providing adequate fit throughout the entire period that the article is worn, and can prevent shape changes during use. In addition, absorbent articles containing these absorbent foam structures may be easier to manufacture on a commercial scale. For example, the absorbent foam cores of the diaper can be simply stamped out of the continuous sheets of foam and can be designed to have considerably greater integrity and uniformity than air-laid fibrous absorbent cores that contain particulate gelling absorbent materials. In addition to absorbency and ease of manufacture, another desirable property of open cell polymer foams is the ability to make formed or contoured absorbent cores having various shape configurations, fluid absorbency properties, and usage characteristics. The formed or contoured absorbent cores made from foam materials have been disclosed in the diaper art. The formed or contoured absorbent cores made from open cell foam materials having the characteristics of particularly desirable fluid transport are disclosed in U.S. Patent No. 5,147,345 issued to Young et al. On September 15, 1992 and the present incorporated and by reference. The core of the 5,147,345 patent of Young et al., Essentially comprises both a fluid acquisition / distribution component and a fluid storage / redistribution component. The fluid acquisition / distribution component is placed within the absorbent article in such a manner as to receive or be in contact with the body's aqueous fluid, which has been discharged to the absorbent article by the user of the article. The fluid storage / redistribution component is instead placed within the article that is in fluid communication with the fluid acquisition / distribution component.

The multi-piece cores that provide the absorbent characteristics of the Young Patent No. 5,147,345 and others in a preferred embodiment are disclosed in the commonly assigned, co-pending application entitled "formed absorbent cores comprising multiple pieces that absorbent material and method for making the Closures ", United States patent application No. (to be inserted when determined), lawyer's document number (to be inserted when determined), filed (to be inserted when determined) on behalf of Gerald Martin Weber, Gerald Alfred Young, Gregory Wade Taylor, and Gary Dean LaVon. The Weber et al. Patent discloses formed absorbers comprising a front panel and a back panel. The rear and front panels are fluid communication with a section • central. Preferably, the central section comprises material generally suitable for acquisition / distribution, while the front and rear panels comprise material generally suitable for the storage / redistribution of the fluid. Despite the advances in the absorbent articles and absorbent core materials that handle the fluid, the absorbent articles that it has in multiple absorbent core components, as well as the unit cores, are generally designed to be worn for a single use. Once the storage / redistribution components are saturated with the bodily discharges, such as urine, the total absorbent article is generally discarded and replaced. Often parts of the absorbent article are still unused, and except for being unitary with the absorbent cores, these parts can be used more. In addition to the additional costs and waste associated with discarded reusable materials, it is often inconvenient to remove and replace the total absorbent article when the absorbent core components are saturated. Absorbent articles with removable absorbent inserts are known in the art. For example, U.S. Patent No. 4,597,761 to Buell, issued July 1, 1986, discloses a disposable absorbent insert for use in an over-garment such as a disposable disposable diaper, or a disposable diaper. Once the absorbent insert is saturated it can be removed and discarded. The absorbent article can then be reused with a new absorbent insert. Buell is representative of a general absorbent article design having a continuous fluid-impermeable backing sheet (backsheet that) and a fluid-permeable body side liner (top sheet) with a removable absorbent core insert disposed therebetween. The absorbent core insert is removed from the body side of the article, necessarily requiring the absorbent article to be removed from the user. These removals are often inconvenient and time consuming. Accordingly, it would be desirable to have an absorbent article having removable or replaceable absorbent core components, wherein the components of the absorbent core can be removed or replaced without having to remove the absorbent article from the wearer. Additionally, it would be desirable to have an absorbent article having an absorbent core having removable or replaceable components and a backsheet -discontinued, allowing the saturated portions of the absorbent core to be removed through the discontinuity of the backsheet, thereby exposing the unsaturated portions and allowing prolonged use of the reusable portions of an absorbent article. In addition, it would be desirable to have an absorbent article with a continuous backsheet affixed to a topsheet around a periphery having removable or replaceable absorbent core components disposed between the top sheet and the backsheet, such as to provide access to the absorbent core components by separating the top sheet and the back sheet in a predetermined area to form an opening.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to absorbent articles suitable for absorbing and retaining aqueous body fluids. A preferred embodiment of the absorbent articles of the present invention comprises a discontinuous backsheet, substantially impervious to the fluid, and an absorbent core disposed adjacent to the backsheet. The absorbent core comprises at least one, and preferably a plurality, of core components that are removable, with the access for removal provided by at least one discontinuity forming an opening in the backsheet. Once removed, the other components of the absorbent core or the layers of the components can remain inside the absorbent article. Also, additional absorbent core components or layers can be added through the opening in the backsheet. In a preferred embodiment, the absorbent article comprises a plurality of components, including at least one front panel, a back panel, and a section •central. Each of the absorbent components can include layers of absorbent members. If saturation occurs with the bodily discharges, certain components or members of the absorbent core can be removed from the absorbent article through the backsheet. Again, the unsaturated absorbent components or members can then be placed in place of the components or saturated members removed, or, more preferably, by removing the saturated component or members, an unused component or member that remains in the position remaining. to be used In a further embodiment, an absorbent article comprises a fluid pervious topsheet, and a continuous backsheet substantially impermeable to the fluid attached to the topsheet around a periphery. A predetermined area of the periphery is separable, whereby the top sheet and the back sheet can be separated to form an opening, providing access to the removable core components disposed between the top sheet and the back sheet. In a particularly preferred embodiment, the absorbent core comprises absorbent front and back panels or components in fluid communication with a central absorbent component. The central absorbent component preferably has characteristics of acquisition or acquisition / distribution of fluid, while the front and back absorbent panels preferably have storage / redistribution characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS Although the description concludes with the claims pointing out in a particular manner and claiming the present invention differently, it is believed that the present invention will be better understood from the following description in combination with the figures of the accompanying drawings, in which similar reference numbers identify similar elements, and where: Figure 1 is a perspective illustration, partially segmented, of an embodiment of an absorbent article according to the present invention. Figure 2 is a side view, showing in partial cross-section, the absorbent article of Figure 1. Figure 3 is a partially segmented, perspective, exploded illustration of a preferred embodiment of an absorbent article according to the present invention. invention. Figure 4 is a side view, showing in partial cross-section, a preferred embodiment of the absorbent article of Figure 3. Figure 5 is a cross-sectional illustration of a preferred embodiment of an aperture configuration in the backsheet in a absorbent article according to the present invention. Figure 6 is a cross-sectional detail of a preferred configuration of the removable components of the absorbent core. Figure 7 is a cross section showing an alternate method of providing a removable and replaceable absorbent core component of an absorbent article according to the present invention. Fig. 8 is a cross section showing a further alternating method of providing a removable and replaceable absorbent core component of an absorbent article according to the present invention. Figure 9 is an exploded perspective view depicting the relationship between the elements of an embodiment of an absorbent core of the present invention. Fig. 10 is an exploded perspective view showing an embodiment of an absorbent article according to the present invention. Figure 11 shows a plan view of an embodiment of an absorbent core useful in an absorbent article according to the present invention. Figure 12 is a sectional elevation view of an absorbent core of Figure 11 taken along line 12-12. Fig. 13 shows an alternate embodiment of an absorbent core similar to that shown in Figs. 11 and 12. Fig. 14 schematically shows an apparatus for forming an embodiment of the absorbent cores formed in accordance with the method of the present invention. Figure 15 schematically shows an apparatus for forming other embodiments of the absorbent cores formed in accordance with the method of the present invention.

Fig. 16 is a plan view of a relatively wide continuous continuous grid after grooving. Fig. 17 is a plan view of a relatively wide continuous rectilinear pattern after a first cutting operation to produce the discrete sections. Figure 18 is a plan view of the discrete sections of the relatively wide rectilinear pattern in layers in spaced relation to the relatively narrow continuous rectilinear plots. Figure 19 is a plan view of the finished formed absorbent cores that the present invention as produced by a method of the present invention.

DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "absorbent core" refers to a material or combination of materials suitable for absorbing, distributing, and storing aqueous fluids such as body exudates. The term "absorbent core component" refers to one of a plurality of absorbent core pieces in a multi-part absorbent core. As used herein the term "absorbent core member" refers to one of a plurality of pieces of an absorbent core component, preferably pieces in a layered relationship. The term "absorbent article" refers to devices that absorb and contain exudates from the body by the use of an absorbent core, and, more specifically, refer to devices that are placed against or close to the user's body to absorb and absorb. contain the various exudates discharged from the body. A preferred embodiment of an absorbent article of the present invention is the disposable absorbent article, diaper 60, as shown in Figure 1. As used herein, the term "diaper" refers to an absorbent article generally worn by infants. and incontinent people which is carried around the user's lower torso. It should be understood, however, that the present invention is also applicable to other absorbent articles such as incontinence briefs, incontinence undergarments, diapers and diaper liners, training pants, diapers, and the like. Figure 1 shows in perspective a partially segmented illustration of an embodiment of an absorbent article 60 according to the present invention. The multi-piece absorbent core 10 comprising the multiple components of the absorbent core, such as the center section 50, the front panel 20, and the rear panel 30, is illustrated and described more fully below with reference to Figure 9. The multi-piece absorbent core 10 also being fully disclosed in the commonly assigned, co-pending application entitled "formed absorbent cores comprising multiple pieces of absorbent material and method for making same", U.S. Patent Application No. (to be inserted when determined), attorney's document number (to be inserted when determined), filed (to be inserted when determined) in the name of Gerald Martin Weber, Gerald Alfred Young, Gregory Wade Taylor, and Gary Dean LaVon, which is hereby incorporated by reference. By forming the absorbent core having discrete components, it is that they have several desired results. First, the core exhibits desirable aesthetics and fit when used in an absorbent article of the present invention due to the use of strips or discontinuous panels of absorbent material. For example, the center section may comprise separate strips or layers, which allow the center section to bend and warp a bit independently of the adjacent strips (and the front and back panels) to provide better fit and comfort in the area of the crotch that is achieved with absorbent cores in one piece. A second advantage of the core formed in sections is the ability to independently form many of the characteristics of the absorbent members. These variations include the acquisition coefficients, distribution coefficients, capacities and storage coefficients, thickness, functionality and the shape or configuration of the absorbent strips or panels. For example, in a preferred embodiment of an absorbent article of the present invention, the three absorbent strip members comprise in the central section, with one of the absorbent strip members having relatively greater acquisition characteristics, and the remaining two having characteristics of relatively larger acquisition / distribution. A third benefit resulting from the multi-piece absorbent core when used in an absorbent article of the present invention is the ability to remove and / or replace the core components of the absorbent core to regenerate the storage / redistribution capacity of the absorbent core 10. As shown in Figure 1, a discontinuity in the backsheet 62 forms the opening 41 and provides access to the components of the absorbent core, for example, the rear panei.; therefore allowing the removal or replacement of the absorbent core components. Figure 2 shows in partial cross-section the embodiment of the absorbent article shown in perspective in Figure 1. The further description of a representative disposable diaper in accordance with the present invention is described below with reference to Figure 9. In Figures 1 and 2, the absorbent core 10 is shown with a middle section layer 50 and a front and rear panel layer, 20 and 30. As the middle section 50 and the rear panel 30 are discrete absorbent components, the rear panel 30 is removable of the absorbent article 60 through the opening 41. Once the back panel 30 is saturated with bodily discharges, such as urine, it can be removed and replaced with a new back panel for continuous use of the absorbent article. As shown in Figures 1 and 2, the disposable diaper 60 is being worn, the flap 42 can be secured over the opening 41 by suitable fasteners 43, such as Sailboat strips or adhesive strips (not shown). More preferably, the fins 42 are sealed with the release adhesive, thus providing impermeability against fluid closed, but allowing multiple opening and closing. The opening 41 forms what can be described as a bag p sac, with the absorbent core components, for example, the back panel 30 being removable and replaceable from the bag. As shown in Figures 1 and 2, to remove the rear panel 30, the flap 42 is raised, and the rear panel 30 is removed from the absorbent article through the aperture 41. To replace the rear panel 30, it can be returned to inserting a new, dry, absorbent component through the backsheet 62 through the opening 41. Figure 2 shows the flap 42 in the closed position over the opening 41 corresponding to the front panel 20 (shown in Figure 1) . In general, the front panel 20, the rear panel 30, and the corresponding openings 41 and the fins 42 are substantially similar, but need not be. In an alternate embodiment, it may only be desired to include an opening 41 and a letter 42, for example, to access the rear panel 30. Replacing the absorbent components, particularly the absorbent components which are primarily suitable for storage / redistribution, the Use of the absorbent article, such as disposable diaper 60, may be prolonged while continuing to remove moisture from the wearer's skin. As the components of the storage / redistribution absorbent core become saturated, for example, the front panel 20 and the back panel 30, these can become substantially less effective in absorbing moisture from the acquisition / distribution components of the center section. As a consequence, the central section 50 becomes more saturated, thus preventing its ability to absorb so much moisture away from the user's skin. However, once the absorbent core components such as the back panel 30 are replaced, the absorbent suction of the core is generated, and again it becomes capable of absorbing moisture from the acquisition / distribution components of the central section. Therefore, the disposable diaper can be worn longer, and the regeneration of the absorbent core can be done without removing the user's diaper. In a preferred embodiment of the absorbent article of the present invention, a discontinuity in the backsheet 62 forms an opening, e.g., the opening 44, in general vicinity of the front and rear panels 20 and 30, as shown in Figures 3 and 4. In this preferred embodiment, a back sheet bag 45 can be attached adjacent the opening 44. The back sheet bag 45 serves to contain and position the front panel 20 (not shown) and the back panel 30 as components that form the members in layers, for example, the individual rear panel members 34, 35 and 36 and figure 4. As a rear panel member, for example, the rear panel member 34, becomes saturated with the body discharge it can be removed through the opening 41 of the backsheet, exposing a dry back panel member, new, for example, to a back panel member 35. The back sheet bag 45 is preferably resilient and foldable, and is a substantially substantial barrier. fluid impermeable over the opening 44, functionally becoming an extension of the backsheet 62. The rear flap 42 is capable of being resealed and preferably resealable, and is preferably positioned in such a way that the flap 42 is secured in a position closed, a rear panel member, for example, the rear panel member 35 is placed in fluid communication with the central section 50. Figure 4 shows the fin 42 in the closed and sealed position s on opening 41 corresponding to front panel 20 (shown in Figure 1). In general, the front panel 20, the rear panel 30, and the corresponding openings 41 and the fins 42 are substantially similar, but need not be. In an alternate embodiment, it may only be desired to include an opening 41 and a flap 42, for example, to access the rear panel 30. Figure 5 shows a preferred embodiment of the arrangement of the rear panels 30, showing again the representative rear panel members 34, 35 and 36, in a relationship in layers adjacent to the opening 41 and in fluid communication with the central section 50. It is understood that the description in the terms of the subsequent panels is equally applicable to the front panels 20. The removal of the back panels through the opening 41 can be facilitated by the use of pull tabs, for example, the tabs 46, which can be of any type known in the art, such as a strip of film plastic attached to each member of the back panel. Additionally, the back panel members may be separated from each other by a blocking layer impervious to fluid 47 such that the adjacent back panel members are not in fluid communication with each other. The layer of 47 can be any fluid impermeable polymer film, such as the film suitable for use as a backsheet impermeable to fluid. As a back panel member becomes saturated by absorption of the fluid from the center section 50, it can be removed, thereby exposing a new, substantially dry back panel member 35 to be additional from the center section 50. this way, the absorbent article can be renewed or regenerated for a prolonged period of time without removing it from the user. Figure 6 shows a particularly preferred embodiment of the layout of the rear panel members. It is understood that the disclosure in the terms of the rear panel members is equally applicable to the front panel members 20. The rear panel members 35 and 36 are shown as representative of the rear panel component 30 in a layered relationship with the blocking layer impermeable to fluid 47 disposed therebetween. The blocking layer 47 is in a layered relationship with the rear panel members 35 and 36 and forms a fluid impermeable layer therebetween. A part of the blocking layer 47 is preferably fixed, for example at the fixing point 48, to the rear panel member that was removed. As a substantially saturated back panel member, e.g., the rear panel member 35, is pulled out of the opening 41 of the backsheet by the pull tab 46, the blocking layer 47 is also pulled out, thus leaving than to the adjacent back panel member, for example, the back panel member 36, in the position to be urged towards fluid communication with the central section 50 through the opening 41. An alternate embodiment of the front and rear panels 20 and 30 of the absorbent article of the present invention is shown in the cross section of Figure 7. Although illustrated in terms of the rear panel 30, it is understood that the description is equally applicable to the front panels 20. As shown in Figure 7, in from providing a back sheet bag 45 attached to the rear sheet 62, a back panel wrap 49 is provided. The back panel wrap 49 has a single single panel 30 wrapped between a layer substantially impervious to fluid 54 and a substantially fluid permeable layer 55, and can be fixed, for example, by suitable adhesives 39 known in the art, to the perimeter 38 of the opening 41. Preferably the rear panel wrap 49 is fixed removably Such a way that the rear panel 30 becomes saturated due to the absorption of the fluid coming from the central section 50 that can be removed and replaced with a new, dry back panel envelope 49.

An alternate embodiment of an absorbent article of the present invention has a backsheet impervious to the fluid without any discontinuity forming an opening through the backsheet. As shown in the cross section of Figure 8, access for removable absorbent core members, for example, members 34 and 35, is provided by opening between an upper sheet 61 and the back sheet 62. As further described completely below with reference to Figure 10, 1 fluid-permeable top sheet is frequently used in absorbent articles as the portion that is in contact with the user of the article. In an article of the present invention, the topsheet 61 and the backsheet 62 may be separable in predetermined areas of the periphery 55, near the waist region 63, either in the front, back, or both. Figure 8 shows the upper sheet and the rear sheet separated in an open position. The opening formed by the separation of the upper sheet and the rear sheet allows the removal and re-positioning of the absorbent core components and is preferably resealable to provide substantial imperviousness to the fluid. The opening can be made resealable, for example, with a suitable adhesive 56 known in the art. Those skilled in the art will recognize the additional embodiments of the absorbent articles that provide access to the absorbent core components that deviate from the scope of the present invention. For example, the rear panel bag 45 can be integrally formed with the backsheet 62 by plastically deforming the backsheet 62 in the area of the backsheet adjacent to the front and rear panels 20 and 30. Then one can make a discontinuity in the backsheet in the form of an opening, by die cutting, for example, to allow access to the front and back panels. A flap similar to flap 42 of Figure 1 can be provided together with fastening means 43, to cover the opening in the backsheet.

In addition, it is contemplated that additional combinations of the components an absorbent core member, absorption and placement characteristics, may be used, with the desired functional requirements influencing the final design without departing from the scope of the present invention. In particular, the absorbent core can be configured as described below.

The Absorbent Core Figure 9 shows an exploded perspective view depicting the elements of an embodiment of the absorbent core 10 formed as it may be used in an absorbent article according to the present invention, for example, in a disposable diaper. As shown in Figures 1, 3, and 11, the absorbent core 10 comprises a front panel 20 and a back panel 30, both made of absorbent material, preferably material suitable for storing / redistributing fluid. The front panel 20 has an outer front end 21, and an inner front end 22, and a pair of sides 23. Similarly, the rear panel 30 has an outer rear end 31, an inner rear end 32, and a pair of sides 33. The front panel 30 has trimmed areas 40 at the intersection of the sides 23, and the inner front end 22. In the same manner, the rear panel 30 has trimmed areas 40 at the intersection of the sides 33, and the end internal back 32. The trimmed areas 40, or notched portions, join the sides and inner ends so that the resulting widths of the inner ends 22 and 32 are narrower than those of the outer ends 21 and 31, respectively. By "notched" it will be understood that the place that one side and the end meet at an angle create between straight, some amount of material is removed from the corner to produce an additional portion of edge that joins the side and the end. The additional edge portion of the notch 40 may be generally straight, but in a preferred embodiment it is concave and generally arcuate, as shown in Figure 11. It is also contemplated that the notch may have generally straight sides, with the limiting example resulting in a rear or front panel that is substantially trapezoidal 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 opposite to and separated from the inner rear end 32 of the rear panel 30 as shown in FIG. Figures 9 to 13. The distance between the front and rear panels can be varied as necessary. In general, the distance will increase as the length of the crotch increases with the size of the absorbent article. The central section 50 is preferably generally rectilinear. By "generally rectilinear" it will be understood that preferably the central section is of substantially constant width along its length. In general, however, the central section 50 only needs to extend and overlap the still and posterior panels 20 and 30, and may have a variable width along its length. When made by the method of the present invention, the central section 50 is generally rectilinear and extends from approximately the outer front end 21 of the front panel 20, to approximately the outer rear end 31 of the rear panel 30 as shown in Figure 10. In use, however, the center section 50 is only required to be in fluid communication with the front and rear panels 20 and 30, preferably overlapping in a layered relationship, and may not extend toward the outer front end 21 or toward the external rear end 31. The generally rectilinear central section 50 may comprise multiple strips of absorbent material, each having individual characteristics of acquisition, acquisition / distribution, or fluid storage / redistribution, as well as individual characteristics of shape, width, length and thickness. For example, in a preferred embodiment, at least two resilient, flexible, relatively thin polymeric foam strips 51 are made from the same storage / redistribution material as the front and rear panels 20 and 30. Strips 51 and the front and rear panels 20 and 30 which, having similar absorption characteristics and which are in fluid communication, act as the main storage / redistribution members. In a preferred embodiment, a generally rectilinear strip 52 comprising a resilient, flexible, relatively thin, polymeric foam material having greater fluid acquisition / acquisition / distribution characteristics than the strips 51, thereby tending to acquire rapidly and dividing the body exudates for the fastest absorption towards the storage / redistribution layers 51 and the front and rear panels 20 and 30. As described with reference to Figures 1 to 4, the fluid absorbent core can be used in disposable products that are capable of absorbing significant amounts of bodily fluids, such as urine, sweat, menstruation, and water in body waste. These articles can be prepared in the form of disposable diapers, adult incontinence trusses, and the like. In general, these absorbent articles generally comprise three basic structural components: a backsheet substantially impermeable to the fluid; an absorbent core; and an upper sheet substantially permeable to fluid. As shown in Figure 10, the backsheet 62 of an embodiment of the absorbent article of the present invention is generally made of material substantially impervious to liquid, but is not continuous. In particular, a discontinuity in the backsheet 62 forms an opening 41, which makes the backsheet 62 permeable to the liquid in the area of the opening 41. Adjacent to the backsheet 62 is an absorbent core 10, which can by itself comprise one or more absorbent components in different layers. Adjacent to the absorbent core 10 and preferably attached to the backsheet is a fluid-permeable upper sheet 61. Preferably, the topsheet 61 and the backsheet 62 are bonded directly to the periphery of the absorbent article by an adhesive or other known bonding means. The technique. The top sheet 61 can also be adhered to the absorbent core. It is also contemplated that the topsheet 61 may be unitary with one or more components of the absorbent core, thereby essentially reducing the absorbent article to two basic structural components: an absorbent core having core components with an integral top sheet, and an back sheet. Figure 10 shows an exploded perspective view of an absorbent core 10 as contemplated for use in a disposable diaper 60 in accordance with the present invention. However, it should be understood that the absorbent core 10 is also useful for other absorbent articles such as incontinence briefs, incontinence pads, training pants, and the like. The diaper 60 shown in Figure 10 is a simplified absorbent article that can represent a diaper before it is placed on a wearer. It should be understood, however, that the present invention is limited to the particular type or configuration of the diaper shown in Figure 10. The disposable diaper 60 is shown in its non-contracted state (ie, with generally all of the contraction induced by the elastic removed) to more clearly show the construction of the diaper 60. The diaper 60 may comprise an upper sheet 61 substantially liquid permeable; a back sheet 62 substantially impermeable to the liquid attached to the top sheet 61; and an absorbent core 10 positioned between the sheet exceeded 61 and the back sheet 62. Additional structural features such as elastic members and fastener for securing the diaper in place on a wearer (such as tape tab fasteners) can also be included. ). Although the topsheet 61, the backsheet 62 and the absorbent core 10 can be assembled in a variety of well-known configurations, a preferred diaper configuration is generally described in U.S. Patent No. 3,860,003 (Buell) issued April 14. January 1975, which is incorporated by reference. Alternatively, the preferred configurations for the disposable diapers herein are also disclosed in U.S. Patent No. 4,808,178 (Aziz et al.) Issued February 28, 1989; U.S. Patent No. 4,695,278 (Lawson) issued September 22, 1987; that and in United States Patent No. 4,816,025 (Foreman) issued March 28, 1989, which are incorporated by reference. Figure 10 shows a preferred embodiment of the diaper 60 in which the topsheet 61 and backsheet 62 are coextensive and have length and width dimensions generally greater than those of the absorbent core 10.1a top sheet 61 which is joined with and over placed on the back sheet 62 thus forming the periphery of the diaper 60. The periphery defines the outer perimeter or edges of the diaper 60. The topsheet 61 is docile, of soft feel, and non-irritating to the wearer's skin. further, the upper sheet 61 is permeable to liquid allowing liquids to easily penetrate through its thickness. A suitable top sheet 61 can be manufactured from a wide range of materials such as porous foams, cross-linked foams, plastic films with openings, natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g. of polyester or polypropylene) from a combination of natural and synthetic fibers. Preferably, the topsheet 61 is made of a hydrophobic material to isolate the user's skin from the liquids within the absorbent core 10. A particularly preferred topsheet 61 comprises fibers of polypropylene cut length having a denier of about 1.5, such as Hercules type 151 polypropylene sold by Hecules, Inc. of Wilmington, Delaware. As used herein, "short length fibers" refers to those fibers having a length of at least about 15.9 millimeters.

There are a number of manufacturing techniques that can be used to manufacture the top sheet 61. For example, the top sheet 61 can be nonwoven, woven, glued, carded, or the like. A preferred top sheet is carded, and thermally bonded by means well known to those skilled in the art of fabrics. Preferably, the topsheet 61 has a weight of about 18 to about 25 grams per square meter, a minimum dry tensile strength of at least about 400 grams per centimeter in the machine direction, and a tensile strength. wetted at least about 55 grams per centimeter in the transverse direction of the machine. Although it is preferred to have a top sheet as the material closest to the user's skin, this is necessary. It is contemplated that a suitable configuration of the absorbent core can be used without a top sheet and still produce the desirable results such as comfort and absorbency, as well as simplicity in manufacturing and cost savings in the material. For example, the body side surface of the absorbent core itself can be made of non-irritating, docile, soft, liquid-permeable materials that replace a separate top sheet. This absorbent core only -would need to be used in combination with a backsheet to provide comfort and absorbency in an absorbent article. The backsheet 62 is made of a material substantially impervious to liquids and is preferably made from a thin plastic film, although other flexible liquid impervious materials may also be used. The backsheet 62 prevents the exudates absorbed and contained by the absorbent core 10 from wetting the articles that are in contact with the diaper 60 such as sheets and undergarments. Preferably, the backsheet 62 is the polyethylene film having a thickness of about 0.012 millimeters about 0.051 centimeters, although other flexible, liquid impervious materials can be used. As used herein, the term "flexible" refers to materials that are docile and that will readily conform to the outline and general shape of the user's body. The polyethylene film of the backsheet can also be used for the flap 42, with suitable adhesive fastening which makes the backsheet of the present invention substantially fluid impervious. A suitable polyethylene film is manufactured by Monsanto Chemical Corporation and commercially available as Film No. 8020. The backsheet 62 is preferably embossed and / or finished dull to provide a more fabric-like appearance. In addition, backsheet 62 can be "breathable", allowing vapors to escape from absorbent core 10 while still preventing exudates from passing through backsheet 62. A backsheet that is highly breathable but substantially impermeable is contemplated. liquid may be desirable for certain absorbent articles. The size of the backsheet 62 is dictated by the size of the absorbent core 10 and the exact design of the selected diaper. In a preferred embodiment, the backsheet 62 has a modified hourglass shape extending beyond the absorbent core 10 at a minimum distance of at least about 1.3 centimeters to at least about 2.5 centimeters around the total periphery of the diaper. Additionally, according to the present invention described more fully below, the backsheet has at least one opening 41 that provides access through the backsheet to a portion of the absorbent core 10. The topsheet 61 and the backsheet 62 are united mutually in any suitable way. As used herein, the term "attached" encompasses configurations by which the upper sheet 61 is directly attached to the back sheet 62 by attaching the upper sheet 61 directly to the back sheet 62, and configurations whereby the topsheet 61 is indirectly attached to the backsheet 62 by fixing the topsheet 61 to intermediate members the cases will be attached to the backsheet 62. In a preferred embodiment, the topsheet 61 and the sheet rear 62 are fixed directly to each other at the periphery of the diaper by attachment means (not shown) such as an adhesive or any other means and attachment as is known in the art. For example, a uniform adhesive layer, continuous, a patterned adhesive layer, or an array of separate lines or spots of adhesive may be used to secure the top sheet 61 to the backsheet 62. The tape tab fasteners 65 they are typically applied to the waistband region 63 of the diaper 60 to provide a fastening means for holding the diaper on the wearer. The tape tab fasteners 65 shown are representative only. The tape tab fasteners may be any of those well known in the art, such as the fastener tape disclosed in United States Patent No. 3,848,594 (Buell) issued November 19, 1974, which is incorporated by reference. These tape tab fasteners or other diaper fastening means are typically applied near the corners of the diaper 60. The elastic members 69 are disposed adjacent the periphery of the diaper 60, preferably along each longitudinal edge 64, in shape such that the elastic members tend to stretch and maintain the diaper 60 against the wearer's legs. Additionally, the elastic members 67 may be arranged adjacent to either or both of the waistband regions 63 of the diaper 60 to provide a waistband as well as or instead of the leg cuffs. For example, a suitable waistband is disclosed in U.S. Patent No. 4,515,595 (Kievit et al.) Issued May 7, 1985, which is incorporated by reference. In addition, a method and apparatus suitable for the manufacture of a disposable honeycomb having elastically shrinkable elastic members is described in U.S. Patent No. 4,081, 301 (Buell) issued March 28, 1978, which is incorporated by reference.

The resilient members are secured to the diaper 60 in an elastically contractible condition in such a manner in a normally unrestricted configuration, the elastic members effectively contract or collect the diaper 60. The elastic members can be secured in an elastically contractible condition at less two ways. For example, the elastic members can be pulled and secured while the diaper 60 is in an uncontracted condition. Alternatively, the diaper 60 can be contracted, for example, by folding, and the elastic members secured and connected to the diaper 60 while the elastic members are in their non-relaxed or undrawn condition. The elastic members may extend along a portion of the length of the diaper 60. Alternatively, the elastic members may extend the total length of the diaper 60, or any other suitable length to provide an elastically contractible line. The length of the elastic members is dictated by the design of the diaper. In use, the diaper 60 is applied to a wearer by placing a waistband region under the user's back, and pulling the rest of the diaper 60 between the user's legs such that the other waistband region is placed across the front of the diaper. user. The tape tab 65 or other fastener is then preferably secured to the outward facing areas of the diaper 60, as shown in Figure 14, for example. In use, the disposable diapers or other absorbent articles of the present invention tend to distribute and store liquids more quickly and efficiently and remain dry due to the high absorbent capacity of the absorbent members of the fluid. Disposable diapers that incorporate the fluid absorbent members of the present invention can also be more delegated and more flexible. When used as an absorbent core in a disposable diaper 60, a preferred embodiment of the core 10 is positioned such that the acquisition / distribution strip 52 is in fluid communication with the upper sheet 61, and serves to acquire and separate rapidly the exudates from the body of the wearer towards the storage / redistribution strips 51 generally more absorbent and the front and rear panels 20 and 30. The front panel generally corresponds to the part of the disposable diaper that is worn on the front of the wearer, with the outer front end 21 which is generally close to the user's waist area. Similarly, the rear panel 30 corresponds to the part of the disposable diaper worn on the back of the wearer, with the outer rear end 31 which is generally close to the wearer's waist area. The generally rectilinear mid section 50 has a width 53 corresponding to a width suitable for the crotch area 66 of a disposable diaper. Also, the length of the center section 50 can be varied to provide a fit of suitable for various sizes of the wearer. Figure 11 shows a top view of an absorbent core 10 formed as a useful embodiment in an absorbent article of the present invention. As shown, the front and rear panels 20 and 30, together with the generally middle section and 50, generally form an elongated hourglass shape suitable for use in a disposable diaper or similar absorbent article. In a modality -preferred, the width 53 of the generally rectilinear central section 50 is suitable for comfortably fitting within the wearer's crotch area when the absorbent core 10 is incorporated within an absorbent article, such as a disposable diaper. The number and placement of the strips 51 or 52 of the generally rectilinear central section 50 can be varied to achieve the desired characteristics such as thinness, softness, flexibility, or coefficients of fluid acquisition, distribution and storage. For exampleFigure 12 shows in cross-section an embodiment using an acquisition / distribution strip 52 and a storage / redistribution strip 51, both placed on the front and rear panels 20 and 30 of storage / redistribution, resulting in an absorbent core 10 thin, flexible By "on" is meant the side of the absorbent core of the invention which corresponds to the wearer's body when used in an absorbent article such as a disposable diaper. The number of layers of the front and rear panels 20 or 30 can also be varied to achieve the desired characteristics such as beneficial fluid acquisition and distribution coefficients, as well as capacity and storage coefficients. If more than one layer of absorbent material is used in the front and rear panels, the panels are referred to herein as components, and the individual layers are referred to herein as members. For example, Figure 13 shows in cross-section an additional embodiment corresponding to the general plan view of Figure 11. Figure 13 depicts two members of the front and rear panels 20 and 30, corresponding, for example, to the members of back panel 34 and 35, shown in Figure 4. As shown in Figure 13, both rear panel members can be placed below the center section 50. As described above with reference to Figures 5 and 6, the Front or rear panel can be separated by fluid impervious material with beneficial results. In summary, the absorbent core 10 comprises a plurality of discrete components, each component capable of having different characteristics of acquisition, acquisition / distribution or storage / redistribution of the fluid. In the context of the present invention, it should be distinguished that the term "fluid" means "liquid". - 'While the acquisition, acquisition / distribution and storage / redistribution components are in fluid communication with adjacent components, they can be placed in relation to one another in a wide variety of configurations. Representative materials suitable for use with the present invention will now be described in greater detail.

The Absorbent Materials As described above, the absorbent core 10 comprises a plurality of discrete components, each component can comprise discrete members, each capable of having different characteristics of acquisition, acquisition / distribution or storage / redistribution of the fluid. The components or members can be made of any material or combinations of materials that have sufficient structural integrity to be handled as a discrete unit. Typical materials known in the art can be used, such as fibrous nonwoven materials, fibrous wet laid web materials, and combinations of fibrous materials having gelling absorbent materials dispersed on or within the fibrous structure. If necessary, these non-woven fibrous materials can be formed into a bag, of material, which is substantially enveloping a fluid-permeable web that provides the structural integrity for removal and placement in the article of the present invention. Particularly preferred absorbent materials for use as the absorbent components or members are foam-based in nature. Polymeric foams that are suitable for use in the fluid acquisition component can generally be characterized as the structures that result when a relatively monomer-free gas or a relatively monomer-free liquid is dispersed as bubbles in a liquid containing monomer polymerizable, followed by the polymerization of the polymerizable monomers in the monomer-containing liquid which surrounds the bubbles. The resulting polymerized dispersion may be in the form of a solidified porous structure which is an aggregate of cells, the boundaries or walls of which cells comprise polymerized solid material. The cells themselves contain the relatively monomer-free gas or the relatively monomer-free liquid, which, before polymerization, has formed the "bubbles" in the liquid. Absorbent foams particularly suitable for absorbent articles such as diapers have been made from High Internal Phase Emulsions (hereinafter referred to as "EAFI"). See, for example, U.S. Patent No. 5,260,345 issued to DesMarais et al. On December 7, 1993, and U.S. Patent No. 5,563,179 issued to Stone et al. On October 18, 1996, each one of which is hereby incorporated by reference. These EAFI absorbent foams provide the desirable fluid handling properties, including (a) relatively good acquisition coefficients for rapidly acquiring urine discharges; (b) relatively good capillary action or wicking and fluid distribution characteristics to transport the urine or other body fluid imbibed away from the initial shock zone and toward the unused balance of the foam structure to allow subsequent jets of fluid are accommodated; and (c) a relatively high storage capacity with a relatively high fluid capacity under load, that is, under compressive forces. The absorbent foams of EAFI that are also flexible and soft enough to provide a high degree of comfort to the wearer of the absorbent article; some can be made relatively thin until they are subsequently wetted by absorbed body fluid. See also the aforementioned Patent No. 5,147,345 to Young et al., And U.S. Patent No. 5,318,554 issued to Young et al. On June 7, 1994, which discloses absorbent cores having an acquiring / distributing component. fluid that can be an open cell, flexible, hydrophilic foam, such as a melamine-formaldehyde foam (eg, BASOTECT * made by BASF), and a fluid storage / redistribution component that is an EAFI-based absorbent foam .

Representative materials suitable for use with the present invention are not limited to EAFI foams, and will be described in greater detail.

The Acquisition Component An absorbent core element is a fluid acquisition component which comprises a porous absorbent structure having certain fluid handling characteristics with respect to the discharged aqueous body fluids, e.g., urine, which pass over and through this structure through of, for example, the top sheet of an absorbent article, as described above. Since the fluid that is frequently discharged in jets, the acquisition component must be able to rapidly acquire, temporarily maintain and also preferably transport (or distribute) the fluid, for example, by capillary action or other mechanisms, from the initial point of fluid contact to other parts of the acquisition component for eventual absorption within the adjacent fluid acquisition / distribution or storage / redistribution components. Any porous absorbent material that will imbibe and distribute the body aqueous fluids towards the acquisition / distribution or storage / redistribution components of the core can be used as the acquisition layer 52. A measure of the fluid acquisition effectiveness of the absorbent material used to form the absorbent material. The acquisition component is the Fluid Acquisition Coefficient, by means of which time measurements taken for the aliquots of the synthetic urine test liquid deposited on the surface of an absorbent material that is absorbed within the internal structure of the material are frozen. absorbent. Fluid acquisition coefficients and suitable test methods are generally disclosed in the aforementioned patent 5,147,345 to Young et al. Accordingly, the fluid acquisition component should be formed from an absorbent material exhibiting an initial Fluid Acquisition Coefficient of at least about 2 millimeters of synthetic urine per second. More preferably, the fluid acquisition component will comprise an absorbent material exhibiting an initial Fluid Acquisition Coefficient of at least about six millimeters of synthetic urine per second. The "Initial" Fluid Acquisition Coefficient is the time taken for the first aliquot of this test liquid to be absorbed into the absorbent material before the material already contains any of the synthetic urine test liquid. Preferred absorbent materials for the acquisition component include synthetic fiber nonwovens, cellulosic nonwovens, and various synthetic / cellulosic nonwovens. A preferred synthetic nonwoven material is disclosed in the commonly assigned U.S. Patent No. 4,988,345 to Reising, issued January 29, 1991, and U.S. Patent No. 4,988,344 to Reising, issued January 29. of 1991, both of which are hereby incorporated by reference. The Reising acquisition layer comprises a first layer of hydrophilic fibrous material of lower average density than the other parts of the first layer in such a way that it rapidly acquires the discharged liquids. A preferred cellulosic nonwoven suitable for the core acquisition components is formed from cellulose fibers that impart certain wet and dry density characteristics to the absorbent core component. More specifically, the portions or regions of an absorbent core that acquires the discharged body fluids will preferably have a dry average density of less than about 0.30 grams / cm 3, and a density averaged when wetted with an aqueous solution of NaCl, 1.0%, less than about 0.20 grams / cm3, and a dry average basis weight of about 0.001 to about 0.10 grams / cm2. Preferred cellulosic nonwoven materials also comprise from about 50% to 100% chemically hardened, twisted and crimped cellulosic fibers, and from about 0% to about 50% binding media. This cellulosic nonwoven material is disclosed in the aforementioned Young Patent 5,147,345 and others, and the commonly assigned U.S. Patent No. 5,531,728 to Lash, issued July 2, 1996, which is hereby incorporated by reference. here for reference. The acquisition layer may be composed of several different materials including synthetic nonwoven webs including polyester, polypropylene or polyethylene, natural fibers including cotton or cellulose, mixtures of these fibers, or any equivalent materials or combinations of materials . Examples of these acquisition materials are more fully described in U.S. Patent No. 4,950,264 to Osborn, issued August 21, 1990, which is hereby incorporated by reference. The cellulosic fibers, in addition to being chemically hardened, can also be advantageously combined with fibers of high surface area, such as eucalyptus fibers, as disclosed in the commonly assigned, co-pending, U.S. Patent Application Serial Number 08 / 686,076 to Seger et al., Filed July 24, 1996, the disclosure of which is hereby incorporated by reference. The chemically hardened fibers and the eucalyptus fibers can be formed in a stratified manner with the thermoplastic binder medium or the chemical binder medium, as taught in the aforementioned Seger reference. A suitable thermoplastic binder, including preferable thermoplastic fibers, is disclosed 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 means may include any thermal melt adhesive that can be melted at temperatures that will not excessively damage the cellulose fibers. Once thermally hardened, the resulting nonwoven material exhibits wet / dry mechanical properties such as flexibility, resilience and structural integrity such that it can be processed as a roll material in the method of the present invention. If chemical binding media are used to give structural integrity to the non-woven material, preferably the absorbent member will comprise between about 80% and about 95% of the chemically hardened fibers, about 3% to 20% of a high surface fiber, and from 0% to about 5% of a chemical additive binder medium. A currently preferred chemical additive binder medium is the polyacrylamide glyoxal resin marketed by Cytec Industries, West Patterson, N.J., under the tradename Parez 631 NC. Suitable additional fiber types and the chemical additive agglutinating medium are disclosed in the commonly assigned U.S. Patent Application Serial No. 08 / 633,630 to Seger et al., Filed on April 17, 1996, the disclosure of which is hereby incorporated herein by reference. Other procurement materials may be prepared by wet laying according to commonly assigned U.S. Patent No. 5,217,445 to Young et al., Issued June 8, 1993, which is hereby incorporated by reference. In general, wet laid webs can be made by depositing an acrylic suspension of fibers on a foraminous forming wire, dehydrating the wet laid suspension to form a wet web, and drying the wet web. Further disclosure of the particular wet laying techniques suitable for forming a suitable core component for use of the present invention are disclosed in the patent., 147,345 to Young et al., Mentioned above. In addition to rapidly acquiring bodily fluids, the absorbent acquisition component of the present invention must efficiently raise this fluid to other fluid acquisition / distribution or storage / redistribution components, including fluid based storage components. of foam. Absorbent foams suitable for use as the acquisition component of the present invention combine relatively high capillary absorption pressures and capacity properties by weight (compared to conventional foams). These foams are disclosed in U.S. Patent No. 5,550,167 issued to DesMarais et al. On August 27, 1996, which is hereby incorporated by reference.

The Components of Acquisition / Distribution of Fluid The fluid acquisition / distribution components may comprise similar materials as the acquisition component, with greater distribution characteristics. Since the body's aqueous fluid is discharged, for example, urine, it frequently discharges into jets, which the acquisition / distribution component must be able to acquire quickly and must also preferably transport the fluid, for -example, by capillary action or wicking effect or other mechanisms, from the point of initial fluid contact makes other parts of the acquisition / distribution component for -the eventual absorption towards the component of storage / redistribution of adjacent fluid. These materials are preferably polymeric foam materials that have a greater degree of dispensing ability so that exudates from the body can be transported more efficiently from the acquisition zone to the storage components of the absorbent core. The absorbent materials comprising the fluid acquisition / distribution component of the articles herein will preferably be suitably effective in transporting the liquid absorbed from one part or region of the acquisition / distribution component to another. The transport of the liquid will often arise by virtue of the tendency of the absorbent material of the acquisition / distribution component to capillary absorb the liquid through its structure. Accordingly, a measure of the effectiveness of the fluid distribution of the absorbent material used to form the acquisition / distribution component relates to the ability of this absorbent material to vertically absorb capillary synthetic urine. The effectiveness of vertical capillary absorption can be measured and quantified in a number of ways, but a typical indicator of vertical capillary absorption performance is the height at which a vertically placed test strip of absorbent material will capillary absorb synthetic urine to from a deposit within a specified period of time. For purposes of the present invention, this height, called Vertical Capillary Absorption Height, is determined by the method described in the above-mentioned patent 5,147,345 to Young et al. The fluid acquisition / distribution component of the articles herein will preferably be formed from the absorbent material exhibiting a Vertical Capillary Absorption Height in 30 minutes of at least about five centimeters. More preferably, the fluid acquisition / distribution component will comprise the absorbent material which has a Vertical Capillary Absorption Height in 30 minutes of at least about 10 centimeters, and most preferably the absorbent material which exhibits a Capillary Absorption Height of 25 centimeters Any porous absorbent material which will imbibe and distribute the body aqueous fluids to the limit set forth hereinbefore can be used in terms of the fluid acquisition coefficient and preferably the vertical capillary absorption height as the, or as part of, the acquisition component. fluid distribution of the absorbent articles disclosed herein. Frequently this absorbent material can be of a foamed and / or fiber-based nature.

A preferred embodiment uses a polymeric, absorbent, open cell foam material, which, in addition to functioning as an acquisition / distribution component in an absorbent core, has improved desorption properties to allow other core components having higher absorption pressures that the desorption pressure of the acquisition / distribution foam to distribute away from the fluid. In particular, the absorbent foams useful in or as the fluid acquisition / distribution component are those having a pore volume of from about two to 100 ml / gram, a specific surface area of capillary deception of from about 0.2 to 1 m2 / gram; a cell size of 10 to 300 microns and a density of approximately 0.01 to 0.5 grams / cm3, provided in a considered manner for these selected parameters such that the "absorbent" foams exceed the aforementioned minimum vertical capillary absorption coefficient. of flexibility, hydrophilic capacity, pore volume, capillary suction, specific surface area, cell size and foam density as related in the present invention are described in greater detail in the above-mentioned patent 5,147,345 to Young et al. open cell, absorbent polymer foam materials suitable for use as the acquisition / distribution components in the present invention are described in the above-mentioned patent 5,563,179 to Stone et al., Other types of non-woven structures suitable for use as the fluid acquisition / distribution component includes structures such as carded frames s, insured, treated with surfactant, macro fiber and synthetic microfiber fibers blown in the molten state, formed pulp webs, shaped fiber cut frames and the like. If non-woven fibrous absorbent structures are used in the present invention, these webs are preferably constructed essentially from chemically hardened hydrophilic cellulosic fibers. These cellulosic fibers are - typically wood pulp fibers that have been hardened with a chemical hardening agent and processed in another manner such that they are formed into a twisted, curled configuration, as fully taught in the aforementioned patent No. 5,147,345 to Young et al. And Lash, as well as U.S. Patent Application Serial No. 08 / 633,630 to Seger et al.

The Storage Components / Fluid Redistribution The absorbent core suitable for use with the present invention comprises at least one, and preferably two, different fluid storage / redistribution components. The fluid storage / redistribution components act to store body exudates-away from the user's body to leave the user feeling dry and to prevent leakage. The storage / redistribution components are maintained in fluid communication with the acquisition or acquisition / distribution layer or layers in such a way that the urine or other aqueous body fluids present in the acquisition / distribution component can be desorbed, being absorbed by the fluid storage / redistribution component or components. The non-woven materials as described above, particularly when combined with particles of hydrogel-forming polymer materials, absorbers, substantially insoluble in water, may be useful as the fluid storage / redistribution component or components. Particularly useful are the non-woven materials containing gelling absorbent materials such as described in U.S. Patent No. 5,061, 259 to Goldman et al., Issued October 29, 1991, U.S. Patent No. 4,654,039. of Brandt et al., issued March 31, 1987 (reissued on April 19, 1988 as Re. 32,649), United States Patent No. 4,666,983 to Tsubakimoto et al., issued May 19, 1987, and U.S. Patent No. 4,625,001 to Tsubakimoto et al., issued November 25, 1986, all of which are hereby incorporated by reference; the macrostructures made from these gelling absorbent materials such as those described in U.S. Patent No. 5,102,597 to Roe et al., issued April 7, 1992, and U.S. Patent No. 5,324,561 to Rezai and others, issued June 23, 1994, both of which are hereby incorporated by reference; the gelling absorbent materials laminated between two layers of tissue such as those disclosed in U.S. Patent No. 4,260,443 to Lindsay et al., issued April 7, 1981, patent of the States. U.S. No. 4,467,012 to Pedersen et al., Issued e! August 21, 1984. Lang's United States Patent No. 4,715,918, issued December 29, 1987, United States Patent No. 4,773,903 to Weisman et al., Issued September 27, 1988; U.S. Patent No. 4,851,069 to Packard et al., issued July 25, 1989; U.S. Patent No. 4,923,454 to Seymour et al., issued May 8, 1990; U.S. Patent No. 4,950,264 to Osborn, issued August 21, 1990; U.S. Patent No. 4,994,037 to Bernardin, issued February 19, 1991; U.S. Patent No. 5,009,650 to Bernardin, issued April 23, 1991; U.S. Patent No. 5,009,653 to Osborn, issued April 23, 1991; U.S. Patent No. 5,128,082 to Makoui, issued July 7, 1992; U.S. Patent No. 5,149,335 to Kellenberger et al., issued September 22, 1992; and U.S. Patent No. 5,176,668 to Bernardin, issued January 5, 1993, all of which are hereby incorporated by reference. A preferred fluid storage / redistribution component of the absorbent core comprises adherent sheets made from particles of hydrogel-forming polymer materials, absorbent, substantially insoluble in water. The sheets may be made by layering predetermined amounts of the hydrogel forming materials with crosslinking and curing agents. A preferred material of this type is disclosed in commonly assigned U.S. Patent No. 5,324,561 to Rezai et al., Issued June 28, 1994, which is incorporated herein by reference. The most preferred fluid storage / redistribution component materials comprise collapsible polymeric foam materials which, upon contact with aqueous fluids (in particular aqueous body fluids such as urine), can expand and absorb these fluids. The polymeric foam absorbent materials comprise a non-ionic, flexible, hydrophilic polymeric foam structure, "of interconnected open cells as disclosed in the United States patent No. ,387,207 issued to Dyer et al. On February 7, 1995, and the co-pending United States Patent Application Serial No. 08 / 563,866 entitled "Absorbent Foam Materials for Aqueous Fluids" made from high internal phase emulsions having proportions of water to very high oil, by DesMarais et al., filed November 29, 1995, both of which are hereby incorporated by reference. In other polymeric absorbent foam materials, the characteristics of the material, and the Characterizing tests are disclosed and taught in the aforementioned patent of the United States No. 5,147,345 to Young and others. The polymeric foam materials useful for use as a storage / redistribution component in an article of the present invention should have high capillary absorption pressures, also known as capillary suction, to effectively desorb adjacent acquisition and acquisition / distribution components. . Capillary absorption pressures can be measured using a vertical capillary absorption absorber capacity test as described in detail in the TEST METHODS section of the Dyer 5,387,207 patent and others mentioned above. The data from the vertical capillary absorption absorber capacity test provide the curve from which the capillary absorption pressure is determined. Preferred absorbent foams for use in an article of the present invention have capillary absorption pressures of about 3 to about 20 centimeters. Particularly preferred absorbent foams have capillary absorption pressures of from about 3 to about 15 cm. The storage / redistribution component of collapsible polymer foam can use low density absorbent foams (when expanded). For a given expanded thickness, these foams with lower density are thinner in their collapsed state than the previous EAF1 absorbent foams. These lower density foams more efficiently utilize the polymeric material available and as a result provide an economically attractive means to achieve thinner absorbent core for absorbent articles such as diapers, each climbing training zone, pads or incontinence trusses. of adults, sanitary napkins, and the like. This is achieved while retaining the absorbency, dryness and desired mechanical properties.

The Method and Apparatus for Making the Absorbent Formed Nuclei A preferred method for the manufacture of the absorbent core formed suitable for use with the present invention is now described with reference to figures 14 to 19. Figure 14 schematically shows a representative apparatus 70 suitable for carrying out the method of forming the components of the absorbent core of the preferred embodiment of the present invention as depicted in Figure 1. The method depicted in Figure 14 and described in detail below can be easily modified to produce absorbent cores comprising different combinations and placements of the absorbent members , such as those shown in FIGS. 12 and 13. Representative modifications are shown schematically in FIG. 15 and, unless otherwise described, can be understood with reference to the description of the method of FIG. 14 since similar numbers identify similar elements. The method is not limited to non-woven weave materials or absorbent polymeric foam materials, but is suitable for use with any generally absorbent material formed into wefts, whether woven or non-woven, fibrous or polymeric, as is known in the art. which can be supplied in roll material and which have sufficient integrity to be processed by the disclosed method. A first relatively narrow rectilinear web 81 is unwound from a supply roll 71. The web 81 has a width generally corresponding to the width 53 of the generally rectilinear central section 50., as shown in Figures 1, 3, 9 and 10. The frame 81 comprises a material suitable for use as an acquisition / distribution layer 52 of the preferred embodiment as shown in Figures 9 and 10. The frame 81 is guided through the entry point 100 on a conveyor 102 where it is placed for further processing as described below. In a preferred embodiment, the second and third relatively narrow rectilinear webs 82 and 83 are unwound, composed of a material suitable for acquisition / distribution or storage / redistribution of the aqueous fluid, from the supply rolls 72 and 73, respectively. The frames 82 and 83 correspond to the storage / redistribution layers 51 of Figures 9 and 10, and may have a width generally corresponding to the width 53 of the center section 50. The frames 82 and 83 are guided through the point of entrance 100 on the conveyor 102 where these are placed in the layers on the frame 81 for further processing as described below.

A relatively wide continuous rectilinear pattern 84 of absorbent material having a longitudinal axis and side sides is unwound from a supply roll 74. In a preferred embodiment, the frame 84 is suitable for use as a core storage / redistribution member. absorbent 10, and is of a suitable width to form in the front panel 20 and the rear panel 30 shown in Figures 1, 3, 9 and 10. The side sides of the screen 84 generally correspond to the sides 23 and 33 shown in FIG. Figure 11. The weft 84 is guided from the roll 74 to a notch forming apparatus 90. The notch forming apparatus 90 preferably comprises two inlet rollers 91 and 92 through which the weft 84 is fed. the web 84 is fed through the inlet 93 of the rollers 91 and 92, the cutting blades (not shown) on the roller 91 cut substantially arched portions from opposite sides of the web 91. the weft 84 in such a way as the weft 84 leaves the notch forming apparatus 90, this appears as shown in Figure 16. Figure 16 shows the continuous rectilinear pattern 84 with substantially arcuate notches 120 at spaced intervals 11 corresponding to the placement of the cutting blades on the roller 91 shown in Fig. '14. The continuous rectilinear pattern 84, with the notches as shown in Figure 16, is then fed into a first slide, cut and set assembly 95 to make cuts transverse to the longitudinal axis to divide the rectilinear pattern 84 into discrete sections 85, and to separate the discrete sections as shown in figure 17. The frame 84 is guided on the rotary drum 96 which serves as a stage. Once in contact with the surface of the rotary drum 96, and before being cut into discrete sections, the weft 84 is moved at a speed lower than that of the surface of the drum and of the sliding relative to the surface of the drum 96 under the light vacuum applied through the perforations in the surface of the drum. Once the weft 84 is cut in the discrete sections 85, a vacuum a little higher is applied so that the divided sections 85 remain in contact with the rotary drum 96, moving at the same speed as the surface of the drum in a separate separate relationship. The cutting rollers 97 rotate in accordance with the rotary drum 96, the diameter of the cutting roller 97 being such that a cutting blade 98 fixed to the cutting roller 97 cuts the rectilinear weft 84 at spaced intervals 121 of FIG. 16, forming the discrete sections 85. As shown in Figure 17, the discrete sections 85 can best be described as being generally rectangular with slotted corners 40, corresponding to the notches 40 of Figure 11. The rotating drum 96 is positioned in such a manner when rotating, the discrete sections 85 are brought into contact with the layer 83 moving on the conveyor 102. The vacuum arrangement in the rotating drum 96 is such that in the contact position with the layer 83, the discrete section 85 it is released from the rotating drum 96 and continues to be carried by the layer 83 via the conveyor 102. The linear speed of the conveyor i 02 is generally equal to the linear speed tangen of the rotary drum 96, in such a way that the discrete sections 85 are deposited in a spaced relation on the layer 83, as illustrated in FIG. 18. FIG. 18 shows in plan view the material that is carried by the conveyor 102. at, for example, point 103 in Figure 14. Layer 83, and layers 82 and 81 below (not shown), form continuous rectilinear patterns below discrete sections 85 which is placed in a separate separate relationship. The discrete sections 85 are spaced apart at spaced intervals 130, which generally correspond to the distance of the transverse center lines 131 of the adjacent discrete sections 85. The material that is carried on conveyor 102 is fed to a second slide and cut assembly 150 to make transverse cuts that divide all the layers of the material. The cutting roller 152 has a diameter that corresponds generally to the distance between the transverse center lines 131 of the discrete sections 85 as shown in Figure 18. The roller 151 serves as a platen for the cutting blade 153 attached to the platen roller. cutting 152. The cutting blade 153 completely divides the layers at or near the transverse center lines 131 of the discrete sections 85. Upon exiting the second slide assembly and cutting 150, the absorbent material has been formed in the individual absorbent cores 10 of the present invention. Various known methods can be used to separate the individual absorbent cores 10, such as by varying the relative speeds of the conveyors 102 and 160. The individual absorbent cores 10 are carried by the conveyor 160 for further processing in the absorbent articles, if necessary, and appear on conveyor 160 in the plan view as shown in Fig. 19. As shown in Fig. 19, it is not necessary for the length of the front panel 20 to be measured from the outer front end 21 to the inner front end 22 to equalize the length of the back panel 30 measured from its outer rear end 31 to its inner rear end 32. The position of the material in layers on the conveyor 102 relative to the second slide and cut assembly 150, determines the relative lengths of the panel front 20 and the rear panel 30. In a preferred embodiment of the present invention, the The back 30 is longer than the front panel 20 as illustrated in Figure 19. This configuration tends itself to better fit when the absorbent article 10 is used in a disposable diaper. As shown in Figs. 13 and 14, the length of the interval 130 can be varied to produce the desired length of the center section 50. It is desirable to be able to vary the length of the center section 50 of an absorbent core 10 for Use in disposable diapers to cover the difference in sizes of children or adults who use these diapers.

Figure 15 shows one embodiment of a method and apparatus such as for producing the core illustrated in Figure 5. Instead of a third relatively narrow rectilinear web 83, unwound from the supply roll 73, the relatively narrow rectilinear web 86 it is unwound from the supply roll 76. The web 86 is then guided to form a top layer of the absorbent material on the conveyor 102. The method continues as described above to form the absorbent core illustrated in Fig. 5. Fig. 15 shows a representative method for forming the absorbent core 10 as shown in Fig. 13. In this embodiment, a relatively wide continuous continuous grid is shown. additional of the matter! absorbent having a longitudinal axis and lateral sides which is unwound from a supply roll 77 and guided to contact and in alignment with the weft 84 before entering the notcher 90. the wefts 84 and 87 may be mutually bonded by known methods for facilitating proper alignment throughout the remainder of the process, particularly after being processed by the slip and cut assembly 95. The method disclosed provides a number of significant benefits. For example, the method generates significantly less waste than a method of forming an absorbent core formed from a part would generate. Also, the method of the present invention provides the efficient supply of wefts of absorbent materials from roll material, especially foam, from which the panels and rectilinear strips are made. An advantage of this process in a long life of the weft roll. For example, the narrower webs of the absorbent material used to make the rectilinear strips can be rolled up on reel for the duration of the roll significantly longer. A third benefit of the method of the present invention is the greater control over certain process variables, such as placement of the core components in the proper operating relationship. For example, because the wider web of the absorbent material is slotted and divided at the point of the front and back panels, it is significantly easier to match the slotted / spaced panels in the proper relationship with the narrower straight strip (s) to form the composite absorbent core. Although the particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications may be made without departing from the spirit and scope of the present invention. The foregoing is, therefore, intended to protect in the appended claims all these changes and modifications that are within the scope of the present invention.

Claims (10)

1. An absorbent article for acquiring bodily fluids from a user, the article comprising a backsheet and the article characterized by: (a) at least one, and preferably at least two, removable absorbent core components disposed adjacent to the backsheet; and (b) the backsheet including means for providing access to the removable absorbent core components through the backsheet, such that the removable absorbent core components can be removed from the absorbent article through the backsheet. An absorbent article according to claim 1, further characterized in that the backsheet comprises material substantially impervious to the fluid and said means for providing access include a backsheet portion which is fluid permeable, such that the portion fluid permeable defines an opening adjacent the removable absorbent core component. 3. An absorbent article according to claim 1 or 2, further characterized in that the removable absorbent core components comprise nonwoven fibrous material, preferably in combination with gelling absorbent materials. 4. An absorbent article according to any of the preceding claims, further characterized in that the removable absorbent core components comprise polymeric foam material of the open cell. An absorbent article according to any of the preceding claims, further characterized in that the removable absorbent core components exhibit absorption pressures of 3 to 20 centimeters, and preferably 3 to 15 centimeters. 6. An absorbent article for acquiring body fluids of a wearer, the absorbent article having a back sheet, a front waist region, a back waist region, a crotch region disposed between the back sheet and the wearer, the core being absorbent characterized by: (a) by at least a first absorbent core component disposed in the crotch region, said first absorbent core component preferably including at least two first absorbent core members in fluid communication in layered relationship; (b) at least one second absorbent core component, said second absorbent core component preferably including at least two second absorbent core members in layered relation, each second 4 member of which absorbent core preferably being removable independently, said second absorbent core component disposed removably in fluid communication with the first absorbent core component; and (c) the backsheet includes means for providing access to the second absorbent core component through the backsheet, such that the second absorbent core component, or the second absorbent core members, can be removed from the backsheet. absorbent article through the back sheet. 7. An absorbent article according to claim 6, further characterized in that the removable absorbent core includes at least one fluid impervious blocking layer disposed between the removable absorbent core members, each fluid impervious blocking layer being preferably bonded. to a removable absorbent core member with one such that each fluid impervious blocking layer is removable with the fixed removable absorbent core member. 8. 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 combination with the open cell polymeric foam material, and more preferably in combination with the gelling absorbent materials. 9. An absorbent article according to claims 6 to 8, further characterized in that the second absorbent core component comprises open cell polymeric foam material, preferably in combination with the fibrous nonwoven material, and more preferably in combination with the gelling absorbent materials. An absorbent article for acquiring bodily fluids of a user comprising a topsheet and a backsheet affixed to the topsheet at a periphery, the absorbent article being characterized by: (a) at least one removable absorbent core component being arranged between the top sheet and the back sheet; and (b) the upper sheet and the backsheet being separable in predetermined areas of the periphery, such that the removable absorbent core component - can be removed from said absorbent article.