MXPA96005288A - Sanita towel - Google Patents

Abstract

The present invention relates to a sanitary napkin that includes an upper sheet, a first back sheet attached to the upper sheet, and an absorbent core placed between said upper sheet and said first back sheet, the first back sheet being initially impermeable to the fluid, said sanitary napkin characterized in that it comprises: a) a second back sheet joined to said first back sheet, the second back sheet including a line of weakness defining a portion of said second back sheet that is separated from the rest of said second back sheet, said second back sheet secured to said first back sheet within said line of weakness in a plurality of bonding sites in such a way that the separation of the part of the second back sheet within said line of weakness forms a plurality of openings in the first back sheet, to selectively make said first back sheet permeable to the flui Such, that the sanitary napkin can be used independently to absorb and contain body exudates or can alternatively be used in combination with an additional sanitary napkin to absorb and contain body exudates when the openings provide fluid communication. through said first posteri sheet

Description

SANITARY TOWEL FIELD OF THE INVENTION The present invention relates to a sanitary napkin, and more particularly, the present invention relates to a sanitary napkin having a second backsheet from which all or a part thereof can be separated from a first backsheet, such that The sanitary napkin can be secured to another sanitary napkin to provide additional absorbent capacity.

BACKGROUND OF THE INVENTION Of course, all the forms and varieties of sanitary napkins configured for the absorption of body fluids are known. In their simplest forms they comprise an absorbent element or core interposed between an element that makes contact with the liquid-permeable body and a protective barrier impervious to liquids. The absorbent element is, of course, intended to receive and contain menses and other vaginal discharges. The element that makes contact with the body (sometimes called a top sheet), is intended to provide more or less comfortable and dry feeling contact with body surfaces while allowing the free passage of fluids throughout the length and towards the absorbent core. The protective barrier (sometimes called a backsheet) is intended to prevent menses or other vaginal discharges that are expelled or that escape the absorbent core that stain the wearer's underwear. In addition to the three functional elements mentioned above, sanitary napkins are generally provided with means for supporting the device adjacent to the crotch area, even while the user moves, where he can more effectively perform his intended function. Traditionally, that means of support has involved the use of surrounding waistbands that have suspensors dependent on the front and the back of the same. The hangers are of various designs and are provided with means of various designs to secure the sanitary towel to this. More recently, sanitary napkins have been provided with a means of bonding adhesive to secure the sanitary napkins to the crotch area of the wearer's undergarment. The elimination of the traditional band is generally considered to be a definitive advance in the technology of sanitary napkins. Although the state of the art of sanitary napkins perform their intended functions, they are limited to the amount of fluid they can absorb due to the capacity of the absorbent element.

BRIEF DESCRIPTION OF THE INVENTION The present invention pertains, in a preferred embodiment, to a sanitary napkin that includes a topsheet, a first backsheet attached to said topsheet, and an absorbent core positioned between said topsheet and said first backsheet. The absorbent article comprises a second back sheet attached to the surface facing the garment or towards the outer surface of said first back sheet. The second back sheet includes a line of weakness that defines a portion of said second back sheet that is separated from the remainder of said second back sheet. The second back sheet is secured to said first back sheet within said line of weakness. Preferably, the second backsheet to the first backsheet is secured within said line of weakness along a plurality of attachment sites. When the separation of the portion of said second back sheet occurs within the lines of weakness, a plurality of openings are formed in the first back sheet. The line of weakness is preferably substantially continuous. The line of weakness may include perforations The surface facing the garment or the exposed surface of the second backsheet, preferably includes a fastening adhesive means. A release release liner preferably covers said fastening attachment means.

BRIEF DESCRIPTION OF THE DRAWINGS Since the description concludes with the claims that particularly point out and claim indistinctly to 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 as reference numbers they identify elements Identical and wherein: Figure 1 is a top plan view of a sanitary napkin embodiment of the present invention with portions of the sanitary napkin cut to show more clearly the construction of the sanitary napkin and with the portion of the sanitary napkin that gives or contracts towards the user, oriented towards the observer; Figure 2 is a cross-sectional view of the sanitary napkin of Figure 1 taken along the sectional line 2-2. Figure 3 is a plan view of the sanitary napkin of Figure 1 with the portion of the sanitary towel facing away from the wearer facing the viewer and with the holding means and the release liner detached to show more clearly the second back sheet; and Figure 4 is a plan view of the sanitary napkin of Figure 3 with the portion of the second back sheet within the line of weakness partially separated from the remainder of the second back sheet.

DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "absorbent article" refers to devices that absorb and contain body exudates, and more specifically refers to devices that are placed against or in proximity to the user's body to absorb and contain the various discharged exudates. of the body. The term "disposable" is used herein to describe absorbent articles that are not intended to be washed or otherwise restored or reused as an absorbent article (ie, they are intended to be discarded after being used only once and , preferably, to be recycled, composted or otherwise disposed of in an environmentally compatible manner). A "unitary" absorbent article refers to absorbent articles that are formed of separate parts joined together to form a coordinated entity so that they do not require separate manipulative parts such as a separate fastener and pad. A preferred embodiment of a disposable absorbent article, unitary 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 that It is used by women adjacent to the pudendal region, usually outside the urogenital region, and is intended to absorb and contain menstrual fluids and other vaginal discharges from the wearer's body (eg, blood, menstruation, and urine). Interlabial devices that reside partially within and partially outside the wearer's vestibule are also within the scope of this invention. As used herein, the term "pudendal" refers to the externally visible female genital organs. However, it should be understood that the present invention is also applicable to other catamenial pads or for feminine hygiene, such as panty liners, or other absorbent articles such as incontinent pads and the like. Figure 1 is a top plan view of the sanitary napkin 20 of the present invention in its flattened state, with portions of the structure cut to show more clearly the construction of the sanitary napkin 20 and with the portion of the sanitary napkin 20 that look at or make contact with the user, oriented towards the observer. As shown in Figure 1, the sanitary napkin 20 preferably comprises a liquid-permeable top sheet 24, a first liquid-impermeable backsheet 26, attached to the topsheet 24., an absorbent core 28 positioned between the upper sheet 24 and the first back sheet 26, and a second liquid impermeable back sheet 29 (shown in Figure 2) secured to the first back sheet 26. The sanitary napkin 20 has two surfaces , a contact surface with the body, surface facing the body, or "body surface" and a surface facing the article of clothing or garment surface. The sanitary towel 20 is shown in Figure 1 as seen from its body surface. The body surface is intended to be worn adjacent to the user's body, while the garment surface is on the opposite side and is intended to be placed adjacent to the wearer's undergarments when the sanitary napkin is used. The sanitary napkin 20 has two center lines, a longitudinal center line "1" and a transverse center line "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 (ie, it is approximately parallel to) a vertical plane bisecting a user standing in halves of the left and right body when using the sanitary napkin 20. The terms "transverse" or "lateral", as used herein, they are interchangeable and refer to a line, axis or direction that lies within the plane of the sanitary napkin 20 which is generally perpendicular to the longitudinal direction. Figure 1 also shows that the sanitary napkin 20 has a periphery 30 which is defined by the outer edges of the sanitary napkin 20 where the longitudinal edges are designated 32 and the end edges are designated 34. Figure 1 shows a preferred embodiment of the sanitary napkin 20 in which the topsheet 24 and the first backsheet 26 have length and width dimensions generally larger than those of the absorbent core 28. The topsheet 24 and the first backsheet 26 extend beyond the edges of the absorbent core 28 to form portions of the periphery 30. Figure 2 is a cross-sectional view of the sanitary napkin 20, taken along the section line 2-2 of Figure 1. As can be seen from the 2, the sanitary napkin 20 preferably includes adhesive fastening means 36 on the exposed surface of the second backsheet 29 for joining the sanitary napkin 20 to the undergarments of the user. Removable, removable liners 37 cover the adhesive fastening means 36 to prevent the adhesive from sticking to a surface other than the crotch portion of the undergarments prior to use.

The absorbent core 28 can be any absorbent means that is capable of absorbing or retaining liquids (for example, menstruation or urine). As shown in the Figure 1, the absorbent core 28 has a body surface, a garment surface, side edges and pad edges. The absorbent core 28 can be manufactured in a wide variety of sizes and shapes (eg, rectangular, oval, hourglass, dog bone, asymmetric, etc.) and from a wide variety of commonly used liquid absorbent materials. in sanitary napkins and other absorbent articles such as shredded wood pulp, which is generally referred to as air felt. An example of other suitable absorbent materials includes folded cellulose wadding; polymers insufflated in the melted state, including coform; chemically stiffened, modified or crosslinked cellulosic fibers; capillary channel fibers; synthetic fibers such as entangled polyester fibers; peat moss; paper, including paper wrappers and paper laminates; absorbent foams; absorbent sponges; superabsorbent polymers; absorbent gelation materials; or any equivalent material or combinations of materials or mixtures thereof. The configuration and construction of the absorbent core may also be varied (for example, the absorbent core may have zones of varying gauge, or profiled to be thicker in the center), hydrophilic gradients, superabsorbent gradients; or may comprise one or more layers or structures. The total absorbent capacity of the absorbent core, however, must be compatible with the design load and intended use of the sanitary napkin. In addition, the size and absorbent capacity of the absorbent core can be varied to accommodate different uses, such as incontinent pads, panty liners, regular sanitary napkins, or nighttime sanitary napkins. Exemplary absorbent structures for use as the absorbent core of the present invention are described in U.S. Patent Nos. 4,950,264, issued to Osborn on August 21, 1990; 4,610,678, issued to Weisman et al. On September 9, 1986; 4,834,735, granted to Alemany et al. On May 30, 1989; and European Patent Application No. 0 198 683, from The Procter & Gamble Company, published on October 22, 1986 in the name of Duenk and others. Each of these patents is incorporated herein by reference. The first back sheet 26 and the top sheet 24 are positioned adjacent the garment surface and the body surface, respectively, of the absorbent core 28 and are preferably bonded thereto and to each other by attachment means (not shown) such as those well known in the art. For example, the first backsheet 26 and / or the topsheet 24 can be secured to the absorbent core 28 or to each other by a uniform, continuous layer of adhesive, a patterned layer of adhesive, or an arrangement of lines, spirals or separate points of adhesive. The adhesives that have been found satisfactory are manufactured by H. B. Fuller Company of St. Paul, Minnesota and sold as HL-1258 or H-2031. The attachment means preferably will comprise an open pattern web of adhesive filaments as described in the U.S.A. 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-filament pattern network comprises several lines of adhesive filaments wound in a spiral pattern as illustrated by the apparatus and methods shown in US Pat. 3,911,173 issued to Sprague, Jr. on October 7, 1975; patent of E.U.A. 4,785,996 issued to Ziecker et al. On November 22, 1978; and patent of E.U.A. 4,842,666 issued to Werenicz on June 27, 1989. Each of these patents is incorporated herein by reference. Alternatively, the joining means may comprise heat bonds, pressure joints, ultrasonic joints, dynamic mechanical joints, or any other joining means or combinations of these joining means as are known in the art. The first backsheet 26 and the second backsheet 29 are impermeable to liquids (eg, menstruation and / or urine) and are preferably manufactured from a thin plastic film, although other flexible, waterproof materials may also be used. liquids. As used herein, the term "flexible" refers to materials that are deformable and will readily conform to the general shape and contour of the human body. The backsheets prevent the exudates absorbed and contained in the absorbent core 28 from wetting articles that come into contact with the sanitary napkin 20, such as pants, pajamas and undergarments. The backsheets can thus comprise a woven or non-woven material, polymeric films such as polyethylene or polypropylene thermoplastic films, or composite materials such as a film-coated nonwoven material. Preferably, each backsheet is a polyethylene film that has a thickness of about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil). Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, United States, under the designation P18-0401, and by Ethyl Corporation, Visqueen Division, of Terre Haute, Indiana, United States, under the designation XP-39385. The backsheets are preferably highlighted or embossed and / or finished in matte to provide a fabric-like appearance. In addition, the backsheets can allow vapors to escape from the absorbent core 28 (i.e., breathe) but at the same time prevent the exudates from passing through the backsheets. Figure 3 is a plan view of the sanitary napkin 20 of the present invention with the portion of the sanitary napkin 20 facing away from the wearer, facing the viewer and with the fastening means 36 and the removable liners 37 removed to show more clearly the second back sheet 29. The second back sheet 29 includes a substantially continuous line of weakness., which defines at least a part of the second back sheet 29, indicated as 41, which can be separated from the rest of the second back sheet. The second back sheet 29 is secured to the first back sheet 26 along a plurality of bonding sites 42. The second back sheet 29 can be secured to the first back sheet 26 along a plurality of bonding sites by any joining means known in the art, such as ultrasonic bonding, heat bonding, or by the use of an adhesive. The attachment sites 42 may be of any size or shape, for example, circular, oval, triangular, rectangular, square, etc. Figure 4 shows the sanitary napkin 20 with the portion 41 of the second backsheet 29 within the line of weakness 40 partially spaced from the remainder of the second backsheet 29, such that a portion of the first backsheet 26 is exposed. Upon separation of the portion 41 from the backsheet a plurality of openings 45 are created in the first backsheet 26, at locations corresponding to the attachment sites 42.

Preferably the first backsheet 26 includes an adhesive (not shown), such that after the portion of the second backsheet 29 has been removed, the sanitary napkin can be secured to another sanitary napkin to provide additional absorbent capacity. On days of light flow, the sanitary napkin 20 can be used as shown in Figures 1 and 2, and can be secured to the undergarment or underpants of the wearer by means of adhesive fasteners 36. However, on days of heavy flow It may be necessary to use multiple pads for additional absorbent capacity. The portion of the second back sheet 29 within the line of weakness 40 can be separated and removed from the remainder of the second back sheet 29, creating openings 45 in the first back sheet 26. The sanitary towel can then be placed on a sanitary napkin additional, such that the fluid flows from the openings 45 in the first back sheet 26 to the upper sheet of the additional sanitary napkin, thereby increasing the total absorbent capacity. The upper sheet 24 is deformable, of soft feeling, and non-irritating to the wearer's skin. In addition, the topsheet 24 is permeable to liquids, allowing liquids (eg, menstruation and / or urine) to easily penetrate through its thickness. A suitable top sheet 24 can be manufactured from a wide range of materials such as woven and nonwoven materials; polymeric materials such as formed thermoplastic films, with apertures, plastic films with apertures, and hydroformed thermoplastic films; porous foams; cross-linked foams; crosslinked thermoplastic films; and thermoplastic meshes. Suitable woven and nonwoven materials may comprise natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polymeric fibers such as polyester, polypropylene or polyethylene fibers) or a combination of natural fibers and synthetic A preferred top sheet comprises a film formed with openings. Films formed with openings are preferred for the upper sheet because they are permeable to body exudates but at the same time non-absorbent and have a reduced tendency to allow liquids to pass back through and re-wet the skin of the body. user. In this way, the surface of the formed film that is in contact with the body remains dry, thereby reducing the staining of the body and creating a more comfortable feeling to the wearer. Suitable shaped films are described in U.S. Patent Nos. 3,929,135, issued to Thompson on December 30, 1975 4,324,246, issued to Mullane et al. On April 13, 1982, 4,342,314, issued to Radel et al. On August 3, 1982 4,463,045, issued to Ahr et al. On July 31, 1984; and 5,006,394, issued to Baird on April 9, 1991. Each of these patents is incorporated herein by reference. The preferred top sheet for the present invention is the formed film described in one or more of the above patents and marketed in sanitary napkins by The Procter & Gamble Company of Cincinnati, Ohio, United States, as "DRI-WEAVE". In a preferred embodiment of the present invention, the body surface of the formed film topsheet is hydrophilic, so as to assist liquids to transfer through the topsheet more rapidly than if the body surface were not hydrophilic, to reduce the possibility that the menstrual fluid leaves the upper sheet instead of flowing into and being absorbed by the absorbent core. In a preferred embodiment, a surfactant is incorporated into the polymeric materials of the formed film topsheet, as described in U.S. Patent Application Serial No. 07 / 794,745, "Absorbing Article Having A Nonwoven and Apertured Film Coversheet "presented on November 19, 1991, by Aziz et al., Which is incorporated herein by reference. Alternatively, the body surface of the topsheet can be made hydrophilic by treating it with a surfactant such as described in the above-referenced U.S. Patent No. 4,950,264, issued to Osborn, incorporated herein by reference.

In use, the sanitary napkin 20 can be held in place by any well-known support means or attachment means for such purposes. Preferably, the sanitary napkin is placed in the wearer's undergarments or panties and secured to them by a fastener, such as an adhesive 36. The adhesive 36 provides means for securing the sanitary napkin in the crotch portion of the panty. In this manner, a portion or all of the outer surface of the second back sheet 29 is coated with adhesive. 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 include Century A-305-IV, manufactured by Century Adhesives Corporation of Columbus, Ohio, United States; and Instant Lock 34-2823, manufactured by National Starch and Chemical Company of Bridgewater, New Jersey, United States. Suitable adhesive fasteners are also disclosed in U.S. Patent No. 4,917,697. Before the sanitary napkin is placed in use, the pressure sensitive adhesive is typically covered with a removable removable liner 37, in order to prevent the adhesive from drying or adhering to a surface other than the crotch portion of the sanitary napkin. panties before use. Suitable release liners are also described in the above-referenced U.S. Patent No. 4,917,697. Any commercially available release liners used for such purposes may be used herein. Non-limiting examples of suitable release liners are BL30MG-A Silox El / O and BL30MG-A Silox 4P / 0, both manufactured by Akrosil Corporation, of Menasha, Wisconsin, United States. The sanitary napkin 20 of the present invention is used by removing the release liner 37 and subsequently placing the sanitary napkin in a pantyhose such that the adhesive 36 contacts the panty. The adhesive holds the sanitary napkin in its position inside the pant during use. In a preferred embodiment of the present invention, the sanitary napkin has two fins, each of which is adjacent to and extending laterally from the lateral edge of the absorbent core. The flaps are configured to hang over the edges of the wearer's panties in the crotch region in such a way that the flaps are disposed between the edges of the wearer's panties and the thighs. The fins serve at least two purposes. First, the fins help prevent staining of the wearer's body and the panties by the menstrual fluid, preferably forming a double wall barrier along the edges of the panty. Second, the fins are preferably provided with attachment means on their garment surfaces in such a way that the fins can be unfolded under the panty, and joined to the garment-facing side of the panty. The fins can be constructed of various materials, including materials similar to the top sheet, back sheet, paper, or combination of these materials. In addition, the flaps may be a separate element attached to the main body of the towel, or may comprise extensions of the top sheet and the back sheet (ie, unitary). A number of sanitary napkins having suitable or adaptable fins for use with the sanitary napkins of the present invention are described in U.S. Patent 4,687,478, issued August 18, 1987 to Van Tilburg; in U.S. Patent 4,589,876, issued May 20, 1986 to Van Tilburg; and in U.S. Patent 4,608,047, issued to Mattingly on August 26, 1986. Each of these patents is incorporated herein by reference. In a preferred embodiment of the present invention, an acquisition layer or layers can be placed between the topsheet and the absorbent core. The acquisition layer can serve several functions, including improving the passage of exudates on and towards the absorbent core. There are several reasons why it is important to improve the passage of exudates, including providing a more even distribution of the exudates throughout the absorbent core, and allowing the sanitary napkin 20 to be made relatively thin. (The fluid passage referred to in it, may encompass the transportation of liquids in one, two or all directions (ie, in the x-y plane and / or in the z-direction)). The acquisition layer may be comprised of several different materials including woven or non-woven webs of synthetic fibers, including polyester, polypropylene, or polyethylene, natural fibers including cotton or cellulose; mixtures of such fibers, or any equivalent material or combinations of materials. Examples of sanitary napkins having an acquisition layer and an upper sheet are fully described in U.S. Patent 4,950,264, issued to Osborn, and U.S. Patent Application Serial Number 07 / 810,774, "Absorbent Article Having Fused Layers ", presented on December 17, 1991, in the name of Cree and others. Each of these references are incorporated herein by reference. In a preferred embodiment, the acquisition layer may be joined to the topsheet by any of the conventional means for joining together webs, most preferably via fusion links as described more fully in the above-referenced Cree application. Although particular embodiments of the present invention have been illustrated and described, it will 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 invention. Therefore, it is intended to cover in the appended claims all those changes and modifications, which are within the scope of this invention.

Claims (8)

NOVELTY OF THE INVENTION CLAIMS

1. A sanitary napkin including a topsheet, a first backsheet attached to said topsheet, and an absorbent core positioned between said topsheet and said first backsheet, said sanitary napkins characterized by: a) a second backsheet attached to said first one back sheet, which includes a line of weakness that defines a portion of said second back sheet that is separated from the rest of said second back sheet, said second back sheet being secured to said first back sheet from said line of weakness. The sanitary napkin according to claim 1, further characterized in that said second back sheet is secured to said first back sheet within said line of weakness along a plurality of bonding sites. 3. The sanitary napkin according to claim 2, further characterized in that on the occurrence of the separation of the portion of said second back sheet within said line of weakness, a plurality of openings are formed in said first back sheet. 4. The sanitary napkin according to any of the preceding claims, further characterized in that said line of weakness is substantially continuous. The sanitary napkin according to claim 4, further characterized in that said line of weakness includes perforations. The sanitary napkin according to any of the preceding claims, further characterized in that said second back sheet has a surface facing the garment. The sanitary napkin according to claim 6, further characterized in that said garment facing surface of said second back sheet includes an adhesive fastening means. The sanitary napkin according to claim 7, further characterized in that said sanitary napkin includes a removable removable liner to cover said adhesive fastening means.