LOW MOTION ZONE SECUREMENT FOR ABSORBENT ARTICLES

Abstract: System for securing an absorbent article, such as a sanitary napkin (29) or the like, to an undergarment which provides enhanced stability of the article in use and enhanced comfort for the wearer. The absorbent article includes two pairs of end wings (37), each pair being located substantially at the ends of the article and with the wings extending outwardly from the opposite side edges, and means (38) for fastening each end wing to the undergarment. The fastening means (38) extend transversely across the backing sheet along each of the ends and outwardly onto the wings. The wings (37) are sized and shaped such that, under in-use conditions, the distal ends (33) of the wings are at least even with, and preferably longitudinally beyond, the ends of the absorbent article.

Description: LOW MOTION ZONE SECUREMENT FOR ABSORBENT ARTICLES CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Serial No. 08/698,527, filed August 15, 1996. FIELD OF THE INVENTION The present invention relates to a securement system for securing an absorbent article such as a diaper, sanitary napkin, panty liner, incontinence pad, or the like to a garment or undergarment. More particularly, the present invention relates to such a securement system which provides for enhanced stability of the absorbent article under in-use conditions, and in turn enhanced comfort for the wearer. BACKGROUND OF THE INVENTION All manner and variety of absorbent articles configured for the absorption of bodily fluids are, of course, well known. Current types of absorbent articles include sanitary napkins, pantiliners, disposable diapers, and incontinent articles. Absorbent articles are subjected to a wide variety of forces under in-use conditions, such as those imposed by the various postures and movements of the wearer. Such forces are exerted on absorbent articles throughout their extent to varying degrees, but are particularly concentrated in the region between the legs of the wearer. In this region the legs of the wearer impart lateral compressive forces on an absorbent article located therebetween, and the movements of the wearer's legs exert torsional and shearing forces on an absorbent article during various movements such as walking, running, etc. Absorbent articles in the feminine protection field such as sanitary napkins and pantiliners are particularly susceptible to these forces, due to their comparatively small size in relation to other absorbent articles and their location essentially within this "high motion" zone. Furthermore, many feminine protection products are secured to the wearer's garments or undergarments by attachment means such as adhesive, foldable flaps, or the like which are also located within this region. Under in-use conditions, the forces exerted by the wearer's legs tend to cause distortion of the garment or undergarment away from its normal shape. This in turn frequently causes the absorbent article to bunch or roll, leading to wearer discomfort and movement of the absorbent article away from the desired location and orientation relative to the wearer's body. These departures from the desired location and orientation in turn increase the likelihood that the absorbent article will not provide the desired protection for the wearer's garments or undergarments. Accordingly, it would be desirable to provide an attachment means for absorbent articles which provides for enhanced securement to garments or undergarments. It would be further desirable to provide such an attachment means for absorbent articles which provides enhanced resistance to a wide range of in-use forces and enhanced wearer comfort. SUMMARY OF THE INVENTION The present invention provides an absorbent article having a longitudinal axis and a transverse axis perpendicular to said longitudinal axis, a fluid pervious topsheet, a fluid impervious backsheet, and an absorbent core between the topsheet and the backsheet. The absorbent article includes two opposed longitudinally-extending side edges and two opposed transversely-extending ends. In accordance with the present invention, the absorbent article further includes a securement means for securing the absorbent article to an undergarment during use comprising two pairs of end wings, each pair of end wings being located substantially concurrently with the ends with one end wing extending outwardly from each of the side edges, and fastening means for securing the end wings to an undergarment during use. The fastening means extends substantially continuously and transversely across the backsheet along each of the ends and outwardly onto the end wings. Securement means in accordance with the present invention are particularly useful when the absorbent article takes the form of a sanitary napkin. Such an absorbent article may additionally employ a pair of flaps extending outwardly from the side edges intermediate the end wings for additional supplemental securement in addition to the end wings. Such flaps are preferably substantially adhesive-free so as to avoid the placement of adhesive products in the crotch area of the absorbent article. In a preferred embodiment, the fastening means preferably comprises a band of pressure-sensitive adhesive extending transversely across the backsheet along the ends of the absorbent article and outwardly onto the end wings. In use, the end wings are folded around the side edges of the undergarment and the adhesive bands are secured to both the wearer-facing side of the undergarment in their central region and to the underside or garment-facing side of the undergarment where the end wings are folded around the side edges of the undergarment. The end wings are sized and shaped such that under in-use conditions the distal ends of the end wings are located at least even with and preferably longitudinally outwardly beyond the ends of the absorbent article. BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the present invention will be better understood from the following description in conjunction with the accompanying drawings, in which like reference numbers identify like elements, and wherein: Figure 1 is a top plan view of an absorbent article according to the present invention in the form of a sanitary napkin; Figure 2 is a cross-sectional view of the sanitary napkin of Figure 1 taken along the section line 2-2; Figure 3 is a perspective view of the crotch portion of a representative undergarment; and Figure 4 is a perspective view of the undergarment of Figure 3 with the absorbent article of the present invention being placed therein with the end wings deployed and secured to the undergarment. DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "absorbent article" refers to devices which absorb and contain body exudates, and, more specifically, refers to devices which are placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body. The term "disposable" is used herein to describe absorbent articles which are not intended to be laundered or otherwise restored or reused as an absorbent article (i.e., they are intended to be discarded after a single use, and, preferably, to be recycled, composted or otherwise disposed of in an environmentally compatible manner). A "unitary" absorbent article refers to absorbent articles which are formed of separate parts united together to form a coordinated entity so that they do not require separate manipulative parts like a separate holder and pad. A presently preferred embodiment of a unitary disposable absorbent article of the present invention is the catamenial pad, sanitary napkin 20, shown in Figure 1. As used herein, the term "sanitary napkin" refers to an absorbent article which is worn by females adjacent to the pudendal region, generally external to the urogenital region, and which is intended to absorb and contain menstrual fluids and other vaginal discharges from the wearer's body (e.g., blood, menses, and urine). Interlabial devices which reside partially within and partially external of the wearer's vestibule are also within the scope of this invention. As used herein, the term "pudendal" refers to the externally visible female genitalia. It should be understood, however, that the present invention is also applicable to other feminine hygiene or catamenial pads such as pantiliners, or other absorbent articles such as diapers, incontinence briefs, and the like. Figure 1 is a plan view of the sanitary napkin 20 of the present invention in its flat-out state with the portion of the sanitary napkin 20 which faces or contacts the wearer, oriented towards the viewer. As shown more clearly in Figure 2, the sanitary napkin 20 preferably comprises a topsheet 28, a fluid impervious backsheet 30 joined with topsheet 28, and an absorbent core 32 positioned between the topsheet 28 and the backsheet 30. The sanitary napkin 20 has two surfaces, a body-contacting surface or body facing surface 20a and a garment facing surface 20b. The sanitary napkin 20 is shown in Figure 1 as viewed from its body facing surface 20a. The body facing surface 20a is intended to be worn adjacent to the body of the wearer while the garment facing surface 20b is on the opposite side and is intended to be placed adjacent to the wearer's undergarments or clothing when the sanitary napkin 20 is worn. The sanitary napkin 20 has two centerlines, a longitudinal centerline "L" and a transverse centerline "T". The term "longitudinal", as used herein, refers to a line, axis or direction in the plane of the sanitary napkin 20 that is generally aligned with (e.g., approximately parallel to) a vertical plane which bisects a standing wearer into left and right body halves when the sanitary napkin 20 is worn. The terms "transverse" or "lateral" as used herein, are interchangeable, and refer to a line, axis or direction which lies within the plane of the sanitary napkin 20 that is generally perpendicular to the longitudinal direction. Figure 1 also shows that the sanitary napkin 20 has a periphery 26 which is defined by the outer edges of the sanitary napkin 20 in which the longitudinal edges (or "side edges") are designated 22 and the end edges (or "ends") are designated 24. Figure 1 shows a preferred embodiment of the sanitary napkin 20 in which the topsheet 28 and the backsheet 30 have length and width dimensions generally larger than those of the absorbent core 32. The topsheet 28 and the backsheet 30 extend beyond the edges of the absorbent core 32 to thereby form not only portions of the periphery but also side flaps 36. Sanitary napkin 20 preferably includes optional side flaps or "wings" 36 that are folded around the crotch portion of the wearer's panties. The side flaps 36 can serve a number of purposes, including, but not limited to protecting the wearer's panties from soiling and keeping the sanitary napkin secured to the wearer's panties. Figure 2 is a cross-sectional view of the sanitary napkin 20 taken along section line 2-2 of Figure 1. As can be seen in Figure 2, the sanitary napkin 20 preferably includes an adhesive fastening means 38 for attaching the sanitary napkin 20 to the undergarment of the wearer. Removable release liners 39 cover the adhesive fastening means 38 to keep the adhesive from sticking to a surface other than the desired portion of the undergarment prior to use or experiencing contamination and degradation. The sanitary napkin 20 can be of any thickness, including relatively thick or relatively thin. The embodiment of the sanitary napkin 20 shown in Figures 1 and 2 is intended to be an example of a relatively thin sanitary napkin. It should be understood, however, when viewing these figures that the number of layers of material shown tends to cause the sanitary napkin to appear much thicker than it actually is. A "thin" sanitary napkin 20 preferably has a caliper of less than about 3 millimeters. The thin sanitary napkin 20 shown should also be relatively flexible, so that it is comfortable for the wearer. Preferably, the sanitary napkin is extensible or stretchable. Examples of extensible or stretchable sanitary napkins are disclosed in commonly-assigned, co- pending (allowed) U.S. patent applications Serial No. 08/472,156, filed June 7, 1995 in the names of Osborn, et al., entitled "Stretchable Absorbent Articles", and Serial No. 08/503,895, filed July 18, 1995 in the names of Osborn, et al., and entitled "Extensible Absorbent Articles", the disclosures of which are hereby incorporated herein by reference. Longitudinal or side edges 22 may also optionally include gathers or pleats (not shown) in the regions between the flaps 36 and the end wings 37 so as to enhance the ability of the absorbent article to assume a cup-like orientation and conform more fully with the wearer's anatormy. In accordance with the present invention, the sanitary napkin 20 is held in place by a securement means or attachment means as depicted in Figures 1 and 2. More particularly, the sanitary napkin is placed in the user's undergarment or panty and secured thereto by a securement means which includes a fastening means such as adhesive 38 for adhering or bonding the sanitary napkin to the undergarment. The adhesive 38 provides a means for securing the sanitary napkin 20 in the "low motion zone" of the panty outside of the crotch region. Thus, a portion of the outer surface of the backsheet 30 is coated with bands of adhesive in the regions depicted in Figures 1 and 2 as central region 31 adjacent to and substantially concurrently with the ends 24 and outwardly onto the elements identified as "end wings" 37 in a preferably narrow band having a width preferably substantially equal to the width of the end wings. Any adhesive or glue used in the art for such purposes can be used for the adhesive herein, with pressure-sensitive adhesives being preferred. Suitable adhesives are manufactured by H. B. Fuller Company of St. Paul, Minnesota, under the designation 2238. Suitable adhesive fasteners are also described in U.S. Patent 4,917,697. Before the sanitary napkin is placed in use, the pressure-sensitive adhesive 38 is typically covered with a removable release liner 39 in order to keep the adhesive 38 from drying out or adhering to a surface other than the crotch portion of the panty prior to use. Suitable release liners 39 are also described in the above-referenced U.S. Patent 4,917,697. Any commercially available release liners commonly used for such purposes can be utilized herein. A non- limiting example of a suitable release liner is BL30MG-A Silox 4P/O, which is manufactured by the Akrosil Corporation of Menasha, WI. The sanitary napkin 20 of the present invention is used by removing the release liner 39 and thereafter placing the sanitary napkin 20 in a panty so that the adhesive 38 contacts the panty. The adhesive 38 maintains the sanitary napkin in its position within the panty during use. Mechanical fastening means for engaging the surface of the undergarment, particularly those of the type which engage the typically fibrous surface of the undergarment, may alternatively be employed if desired. As depicted in Figures 1 and 2, in accordance with the present invention the attachment means 38 is oriented transversely across the ends 24 of the sanitary napkin and extends substantially continuously laterally outwardly beyond the edges of the absorbent core 32 and beyond the longitudinal edges 22 as well onto the end wings 37. These end wings 37, both by being located outside the crotch region of the panty and by providing a significant transverse expanse of adhesive, provide enhanced stability and security of the sanitary napkin relative to the panty or undergarment. The adhesive attachment means 38 also serve to prevent the ends of the sanitary napkin from curling upwardly away from the undergarment during use due to their being located substantially concurrently with the ends 24 of the sanitary napkin and extending inwardly therefrom. In similar fashion, the adhesive attachment means 38 preferably extend substantially outwardly along the end wings 37 from a central region 31 to a location substantially adjacent to, if not in fact fully currently with, the distal ends 33 of the end wings 37 so as to prevent the distal ends from curling upwardly away from the undergarment during use. The backsheet is preferably substantially free of the fastening means (adhesive) in the region between the bands which extend across the ends and onto the end wings such that some degree of relative movement is permitted between the central or crotch region of the garment or undergarment and the central region of the sanitary napkin. An additional benefit is the reduction in likelihood of the adhesive coming; into contact with sensitive anatomical regions. In accordance with the present invention, the end wings 37 extend sufficiently outwardly beyond the longitudinal edges 22 of the absorbent article so as to be able to wrap around and capture the edges of the leg openings of the wearer's garment or undergarment, thereby providing additional stability and security beyond that portion of the adhesive fastening means 38 which is adhered to the inner surface of the undergarment. Not only do the end wings extend sufficiently outwardly so as to capture the edges of the leg openings, but due to the presence of the adhesive fastening means on the distal ends of the end wings the end wings engage and bond to the outer surface of the undergarment such that in the vicinity of the distal ends both surfaces of the undergarment are engaged by and secured to the end wings of the sanitary napkin. Moreover, the end wings are secured directly to the undergarment by virtue of the adhesive fastening means rather then being secured to themselves or other portions of the sanitary napking, thereby ensuring that relative motion between the undergarment and the end wings is effectively prevented. The end wings 37, in a pre-use condition such as shown in Figure 1 , preferably extend laterally outwardly from the longitudinal edges 22 in a direction substantially perpendicular to the longitudinal axis of the absorbent article (i.e., substantially parallel to the transverse axis). However, if desired, the end wings 37 could be positioned at an angle other than perpendicular to the longitudinal axis. Due to the fact that most typical garments or undergarments have angled leg openings so as to provide an increasing garment width as distance from the central crotch region increases, the folding of the end wings 37 around the angled edge of the leg opening of the undergarment results in the distal ends 33 of the end wings 37 assuming a diverse angular relationship to the central region 31 of the adhesive attachment means 38 (as shown in Figure 4) even when the end wings are oriented substantially perpendicularly to the longitudinal axis (as shown in Figure 1). This orientation of the end wings when secured to the undergarment provides further enhanced securement of the sanitary napkin under the wide range of conditions encountered during use. The end wings are sized and adapted such that under in-use conditions such as shown in Figure 4, the distal ends 33 are located at least even with and preferably longitudinally outwardly beyond the ends of the sanitary napkin. This orientation enables the end wings to exert a tensioning force upon the sanitary napkin in the longitudinal direction to provide enhanced stability and fit. This resulting configuration is a function of three primary end wing design variables: the length of the wings beyond the peripheral edges of the sanitary napking, the angle of the wings relative to the longitudinal centerline of the sanitary napkin, and the longitudinal location of the end wings relative to the ends of the sanitary napkin. The end wings may be formed as separate structural elements and secured by any suitable means to the side edges of the absorbent article adjacent to the ends. Preferably, however, the end wings are unitarily formed from the topsheet and backsheet materials as lateral extensions thereof. For ease of manufacture and for enhanced comfort for the wearer, the end wings preferably have substantially rounded outer edges so as to be generally lobe-shaped. While the end wings may be of any appropriate size and/or shape, for aesthetic as well as functional reasons a generally symmetrical arrangement is presently preferred wherein each pair of end wings comprises two end wings of substantially similar size and shape symmetrically located with respect to the longitudinal axis. In addition, under some circumstances it may be desirable to provide an asymmetrical arrangement of end wings with regard to the longitidinal axis, or to provide end wings which differ in size and/or shape from one pair to the other. However, again for aesthetic as well as functional reasons it is presently preferred that the end wings be provided in the form of two pairs of end wings of substantially similar size and shape having a symmetrical orientation with respect to the longitudinal axis of the absorbent article. It is further preferred for convenience of use, but not essential, that the absorbent article (including the shape and location of the end wings) exhibit symmetry with regard to the transverse axis. In a preferred embodiment of the present invention, the sanitary napkin 20 also has two flaps 36 each of which are adjacent to and extend laterally from the side edge of the absorbent core intermediate the end wings. The flaps 36 are configured to drape over the edges of the wearer's panties in the crotch region so that the flaps are disposed between the edges of the wearer's panties and the thighs. The flaps 36 serve at least two purposes. First, the flaps 36 help serve to prevent soiling of the wearer's body and panties by menstrual fluid, preferably by forming a double wall barrier along the edges of the panty. Second, the flaps 36 may optionally be provided with attachment means (such as adhesive) on their garment-facing surface so that the flaps can be folded back under the panty and attached to the garment facing side of the p-inty. Preferably, however, these flaps are substantially free of adhesive and are instead self-biasing so as to capture the crotch portion of the panty therebetween, such as is described in greater detail in Published PCT Application WO 94/08419, published February 2, 1995 naming Weinberger et al. as inventors, and Published PCT Application WO 94/02096, published February 3, 1994 naming Lavash et al. as inventors, the disclosures of which are hereby incorporated herein by reference. In this way, the flaps 36 aid in keeping the sanitary napkin 20 properly positioned in the panty, supplementing the securement provided by end wings 37. By being substantially adhesive-free, some relative movement is permitted between the central or crotch region of the garment or undergarment and the central region of the sanitary napkin. An additional benefit is the reduction in likelihood of the adhesive coming into contact with sensitive anatomical regions. The flaps 36 can be constructed of various materials including materials similar to the topsheet, backsheet, tissue, or combination of these materials. Further, the flaps 36 may be a separate element attached to the main body of the napkin or can comprise extensions of the topsheet and backsheet (i.e., unitary). A number of sanitary napkins having flaps suitable or adaptable for use with the sanitary napkins of the present invention are disclosed in U.S. Pat. No. 4,687,478 issued to Van Tilburg on August 18, 1987; U.S. Pat. No. 4,589,876 issued to Van Tilburg on May 20, 1986; and U.S. Pat. No. 4,608,047 issued to Mattingly on August 26, 1986. Each of these patents are incorporated herein by reference. Figure 3 is a depiction of the crotch portion 14 of a typical representative undergarment 11 of the type commonly worn by many women and well known as a panty. A panty 11 comprises a front section 10, a back section 12, and a crotch portion 14 which joins the front and back sections. The crotch portion 14 comprises two side edges 16 and center crotch portion 18. The sanitary napkin 20 of the present invention may be utilized by removing the release liners 39 from the adhesive fasteners 38 and placing the sanitary napkin 20 in a panty 11 as shown in Figure 4. The central portion of the backsheet 30 of the sanitary napkin 20 is placed in crotch portion 14 of the panty with one end 24 of the sanitary napkin 20 extending toward the front section 10 of the panty and the other end 24 extending toward the back section 12. The centrally located flaps 36 are deployed around the side edges 16 of the panty. The distal ends 33 of the end wings 37 are folded around the side edges 16 of the panty on either side of the flaps 36, and the adhesive fasteners 38 are secured both to the wearer-facing side of the panty in their central region 31 and to the underside of the panty in their regions which extend outwardly onto the end wings 37. The panty is then pulled up into position on the wearer's lower torso. The absorbent core 32 may be any absorbent means which is capable of absorbing or retaining liquids (e.g., menses and or urine). As shown in Figure 1, the absorbent core 32 has a body facing surface, a garment facing surface, side edges, and end edges. The absorbent core 32 may be manufactured in a wide variety of sizes and shapes (e.g., rectangular, oval, hourglass, dog bone, asymmetric, etc.) and from a wide variety of liquid-absorbent materials commonly used in sanitary napkins and other absorbent articles such as comminuted wood pulp which is generally referred to as airfelt. Examples of other suitable absorbent materials include creped cellulose wadding; meltblown polymers including coform; chemically stiffened, modified or cross-linked cellulosic fibers; synthetic fibers such as crimped polyester fibers; peat moss; tissue including tissue wraps and tissue laminates; absorbent foams; absorbent sponges; superabsorbent polymers; absorbent gelling materials; or any equivalent material or combinations of materials, or mixtures of these. The configuration and construction of the absorbent core may also be varied (e.g., the absorbent core 32 may have varying caliper zones (e.g., profiled so as to be thicker in the center), hydrophilic gradients, superabsorbent gradients, or lower density and lower average basis weight acquisition zones; or may comprise one or more layers or structures). The total absorbent capacity of the absorbent core 32 should, however, be compatible with the design loading and the intended use of the sanitary napkin 20. Further, the size and absorbent capacity of the absorbent core may be varied to accommodate different uses such as incontinence pads, pantiliners, regular sanitary napkins, or overnight sanitary napkins. In addition, the absorbent core 32 may be comprised of certain materials or configurations to provide flexibility, if so desired. Exemplary absorbent structures for use as the absorbent core 32 of the present invention are described in U.S. Pat. No. 4,950,264 issued to Osborn on August 21, 1990; U.S. Pat. No. 4,610,678 issued to Weisman et al. on September 9, 1986; U.S. Pat. No. 4,834,735 issued to Alemany et al. on May 30, 1989; and European Patent Application No. 0 198 683, The Procter & Gamble Company, published October 22, 1986 in the name of Duenk, et al. Each of these patents are incorporated herein by reference. The backsheet 30 and the topsheet 28 are positioned adjacent the garment facing surface and the body facing surface, respectively, of the absorbent core 32 and are preferably joined thereto and to each other by attachment means (not shown) such as those well known in the art. For example, the backsheet 30 and/or the topsheet 28 may be secured to the absorbent core 32 or to each other by a uniform continuous layer of adhesive, a patterned layer of adhesive, or an array of separate lines, spirals, or spots of adhesive. Adhesives which have been found to be satisfactory are manufactured by H. B. Fuller Company of St. Paul, Minnesota, under the designation HL-1258, and by Findlay of Minneapolis, Minnesota, under the designation H-2031. The attachment means will preferably comprise an open pattern network of filaments of adhesive as is disclosed in U.S. Pat. No. 4,573,986 issued to Minetola, et al. on March 4, 1986, and which is incorporated herein by reference. An exemplary attachment means of an open pattern network of filaments comprises several lines of adhesive filaments swirled into a spiral pattern such as illustrated by the apparatus and method shown in U.S. Pat. No. 3,911,173 issued to Sprague, Jr. on October 7, 1975; U.S. Pat. No. 4,785,996 issued to Zieker, et al. on November 22, 1978; and U.S. Pat. No. 4,842,666 issued to Werenicz on June 27, 1989. Each of these patents are incorporated herein by reference. Alternatively, the attachment means may comprise heat bonds, pressure bonds, ultrasonic bonds, dynamic mechanical bonds, or any other suitable attachment means or combinations of these attachment means as are known in the art. The backsheet 30 has a body facing surface and a garment facing surface. The backsheet 30 is impervious to liquids (e.g., menses and/or urine) and is preferably manufactured from a thin plastic film, although other flexible liquid impervious materials may also be used. As used herein, the term "flexible" refers to materials which are compliant and will readily conform to the general shape and contours of the human body. The backsheet 30 prevents the exudates absorbed and contained in the absorbent core 32 from wetting articles which contact the sanitary napkin 20 such as pants, pajamas and undergarments. The backsheet 30 may thus comprise a woven or nonwoven material, polymeric films such as thermoplastic films of polyethylene or polypropylene, or composite materials such as a film-coated nonwoven material. Preferably, the backsheet is a polyethylene film having a thickness of from about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mils). Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation PI 8-1401 and by Tredegar Film Products of Terre Haute, Indiana, under the designation XP-9818. The backsheet is preferably embossed and/or matte finished to provide a more clothlike appearance. Further, the backsheet 30 may permit vapors to escape from the absorbent core 32 (i.e., breathable) while still preventing exudates from passing through the backsheet 30. The topsheet 28 is compliant, soft feeling, and non-irritating to the wearer's skin. Further, the topsheet 28 is liquid pervious permitting liquids (e.g., menses and/or urine) to readily penetrate through its thickness. Suitable topsheets may be manufactured from a wide range of materials such as woven and nonwoven materials; polymeric materials such as apertured formed thermoplastic films, apertured plastic films, and hydroformed thermoplastic films; porous foams; reticulated foams; reticulated thermoplastic films; and thermoplastic scrims. Suitable woven and nonwoven materials can be comprised of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polymeric fibers such as polyester, polypropylene, or polyethylene fibers), or from a combination of natural and synthetic fibers. Preferred topsheets comprise an apertured formed film. Apertured formed films are preferred because they are pervious to body exudates and yet non-absorbent and have a reduced tendency to allow liquids to pass back through and rewet the wearer's skin. Thus, the surface of the formed film which is in contact with the body remains dry, thereby reducing body soiling and creating a more comfortable feel for the wearer. Suitable formed films are described in U.S. Pat. No. 3,929,135, issued to Thompson on December 30, 1975; U.S. Pat. No. 4,324,246 issued to Mullane, et al. on April 13, 1982; U.S. Pat. No. 4,342,314 issued to Radel. et al. on August 3, 1982; U.S. Pat. No. 4,463,045 issued to Ahr et al. on July 31, 1984; 4,637,819 issued to Ouellette, et al. on January 20, 1987, and U.S. Pat. No. 5,006,394 issued to Baird on April 9, 1991. Each of these patents are incorporated herein by reference. Other suitable foπned films include hydroformed films such as those disclosed in U.S. Pat. No. 4,629,643, issued December 16, 1986 to Curro et al., and U.S. Pat. No. 4,609,518, issued September 2, 1986 to Curro, both of which are also hereby incorporated herein by reference. Preferred forms of hydroformed films would include those having microapertures formed therein. The topsheet may optionally be comprised of a multilayer polymeric film which exhibits an opaque appearance. Such a multilayer film includes a first outer layer comprised substantially of a polymeric material and a central filler-con aining polymeric layer substantially continuously joined to one side of the first outer layer. The central filler-containing layer may include about 20 to 60 weight percent fillers relative to the filler-containing layer which are substantially uniformly dispersed therein. A filler such as titanium dioxide or carbonate may be used to give the topsheet a whitish, opaque appearance. The central filler-containing layer has a thickness from about 30 to about 70 percent of the total thickness of the multilayer film. A second outer layer comprised substantially of a polymeric material has one side substantially continuously joined to the second side of the central filler-containing layer. The total multilayer film preferably has at least 20 weight percent filler relative to the total multilayer film. A suitable example of such a multilayer topsheet is found in commonly assigned U.S. Patent No. 5,261,899, issued November 16, 1993 to Visscher and Perry, which is hereby incorporated herein by reference. Preferred polymeric materials for the outer layers and the central filler-containing layer include polyolefins, particularly polyethylenes, polypropylenes and copolymers having at least one olefinic constituent. Other materials such as polyesters, nylons, copolymers thereof and combinations of any of the foregoing may also be suitable. The topsheet may alternatively comprise a fluid-pervious nonwoven web preferably formed of a synthetic fibrous material such as polypropylene, polyester, or polyethylene, natural fibers such as wood, cotton, or rayon, or combinations of natural and synthetic fibers, as well as various paper, tissue, or paper-like fibrous materials. Nonwoven webs may be apertured by techniques known in the art. such as needle punching, hydroentangling, etc. The topsheet and backsheet are bonded to one another in the area of the flaps and the end wings by any one of the various bonding methods known in the art. Suitable methods include adhesive bonding such as a uniform continuous layer of adhesive, a patterned layer of adhesive, or an array of separate lines, spirals, or spots of adhesive, or other methods such as heat bonds, pressure bonds, ultrasonic bonds, dynamic mechanical bonds, or any other suitable attachment means or combinations of these attachment means as are known in the art. A presently preferred bonding method comprises heat sealing of the marginal edges of the topsheet and backsheet by methods well known in the art as being suitable for such purposes.. Such a bonding method provides a suitable bond between the materials which has sufficient integrity to survive various assembly and configuration processes yet does not overly stiffen the flaps or end wings. Particularly when a thermal bonding method is utilized, it is preferred that the materials utilized for the topsheet and backsheet be thermally similar (i.e., have a similar melting temperature and melting properties). In accordance with the present invention, it is preferred that at least the body facing surface of the topsheet is hydrophilic so as to help liquid to transfer through the topsheet faster than if the body facing surface was not hydrophilic so as to diminish the likelihood that menstrual fluid will flow off the topsheet rather than flowing into and being absorbed by the absorbent core. Alternatively, the topsheet could be hydrophobic, at least to a degree. In a preferred embodiment, the topsheet is made hydrophilic by treatment with a surfactant such as is described in the above referenced U.S. 4,950,254 issued to Osborn, incorporated herein by reference. Alternatively, surfactant may be incorporated into the polymeric materials of the topsheet such as is described in the above-referenced published PCT application WO 93/09741, entitled "Absorbent Article Having A Nonwoven and Apertured Film Coversheet", published May 27, 1993 naming Aziz et al. as inventors, incorporated herein by reference. While 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 can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims: WHAT IS CLAIMED IS: 1. An absorbent article, preferably a sanitary napkin, having a longitudinal axis and a transverse axis perpendicular to said longitudinal axis, a fluid pervious topsheet, a fluid impervious backsheet, an absorbent core between said topsheet and said backsheet, two opposed longitudinally-extending side edges and two opposed transversely-extending ends, and a securement means for secuiing said absorbent article to an undergarment during use, characterized in that said securement means comprises: (a) two pairs of end wings, each pair of end wings being located substantially concurrently with said ends with one end wing extending outwardly from each of said side edges and preferably being unitarily formed from said topsheet and said backsheet, said end wings preferably having substantially rounded outer edges; and (b) fastening means for securing said end wings to an undergarment during use, said fastening means preferably comprising a band of adhesive, more preferably pressure-sensitive adhesive, said fastening means extending substantially continuously and transversely across said backsheet along each of said ends and outwardly onto said end wings. 2. The absorbent article of Claim 1, further characterized in that said absorbent article further includes a pair of flaps, preferably unitarily formed from said topsheet and said backsheet, extending outwardly from said side edges intermediate said end wings, said flaps preferably being substantially adhesive- free and preferably being centrally located. 3. The absorbent article of Claim 2, further characterized in that said end wings have distal ends located remotely from said side edges, and characterized in that said adhesive extends outwardly to a location substantially adjacent to said distal ends of said end wings. 4. The absorbent article of any of Claims 1 to 3, further characterized in that each pair of end wings comprises two end wings of substantially similar size and shape. 5. The absorbent article of any of Claims 1 to 4, further characterized in that end wings of one pair of end wings are substantially similar in size and shape to end wings of the other pair of end wings. 6. The absorbent article of any of Claims 1 to 5, further characterized in that said end wings have distal ends located remotely from said side edges, and wherein said end wings are sized and adapted such that under in-use conditions said distal ends are located at least even with said ends of said absorbent article. 7. The absorbent article of any of Claims 1 to 6, further characterized in that said end wings have distal ends located remotely from said side edges, and wherein said end wings are sized and adapted so as to engage both surfaces of said undergarment in the vicinity of said distal ends. 8. The absorbent article of any of Claims 1 to 7, further characterized in that said pairs of end wings each comprise two end wings symmetrically located with respect to said longitudinal axis. 9. The absorbent article of any of Claims 1 to 8, further characterized in that fastening means comprises a band extending transversely across said backsheet along each of said ends and outwardly onto said end wings, said backsheet being substantially free of said fastening means between said bands. 10. The absorbent article of any of Claims 1 to 9, further characterized in that said end wings extend laterally outwardly from said side edges in a direction substantially perpendicular to said longitudinal axis.

Inventors: ADKINS HEATHER LEAH, ADKINS, HEATHER, LEAH
Applicants: PROCTER & GAMBLE, THE PROCTER & GAMBLE COMPANY
Application year: 1997
Main classification: A61F13
IPC codes: A61F13