MXPA97004657A - Absorbent article with a preform member - Google Patents

Abstract

An absorbent article with an outer perimeter having a cover, a liquid-impervious preformed member and an absorbent core positioned therebetween is described. The preformed member has a protrusion for a close contact of the body between the wearer and the absorbent article and a barrier means for intercepting the body fluid queried from the absorbent core towards the outer perimeter of the sanitary napkin. The protrusion extends over the surface that gives the body of the absorbent core while the barrier means surrounds the absorbent core and extends over the periphery of the absorbent core.

Description

ABSORBENT ARTICLE WITH A PREFORMED MEMBER This invention relates generally to disposable absorbent articles to absorb body fluid and in particular to thin sanitary napkins to absorb menstrual fluid. All the variety of absorbent means has been configured for the absorption of bodily fluids, such as menstruation and are well known. It is expected that these means absorb body fluid, retain it inside and prevent the evacuated body fluids from staining the person and / or clothing. In the formation of these disposable absorbent means, they commonly include a liquid-permeable cover that gives the body an absorbent core and a backsheet or liquid-impermeable partition layer. These absorbent means, used as diapers, incontinence garments or sanitary napkins, are subject to failure. The spillage of the absorbent media is generally attributed to a high concentration of fluid absorption at the point of fluid attack. At this point, the absorbent material in the medium becomes oversaturated and can not accept, to a considerable degree, additional body fluids. Using a sanitary napkin as an example, menstruation will generally migrate radially from the point of attack and spill from the sides. This usually causes the wearer to stain, usually around the region of the thighs and the undergarment. In the area of sanitary napkins, it has been suggested that at least 20-25 percent of all sanitary napkins experience lateral spillage. This incidence of spillage increases for those sanitary towels with absorbency designed mainly for medium to thick flow. To overcome the problem of lateral spillage, sanitary napkins have been constructed with elasticized sides that push the sides upwards or cause the sanitary napkin to form a cup. Another method to avoid lateral spillage has been to spread wings, fins or cloths (hereinafter wings) from the edges of the sanitary napkin. The wings generally extend over the edges of the undergarment and adhere to the underside of the crotch portion or to themselves. The wings usually help the garment adhesive, if present, keep the sanitary pad in position during use. However, it is possible that these elasticized edges or wings will bend inwardly, partially occluding the cover surface and thereby decreasing the efficacy of the sanitary napkin. In some cases this fold causes the edges to actually contribute to the incidence of the failure.

Improving the performance of sanitary napkins continues to be a formidable compromise, although several improvements have been made in both materials and construction. However, the elimination of the spill, particularly along the inside of the thighs without compromising the comfort and fit, has not met the desired needs of the consumer. Therefore, the need remains for a sanitary napkin that is comfortable to wear while decreasing the possibility of lateral spill associated with the use of sanitary napkins during the menstrual period. The present invention aims to overcome the above problems of the absorbent means of the prior art. The object is solved by the absorbent article according to the independent claims 1 and 22. Other advantages, characteristics, aspects and details of the invention are evident from the dependent claims, the description and the attached drawings. The claims should be understood as a first non-limiting procedure for defining the invention in general terms. Briefly, this invention relates to disposable absorbent articles and in particular to sanitary napkins which are designed to absorb bodily fluids, such as menstrual fluid and other excrements evacuated by the body during a menstrual period. More particularly, the present invention relates to sanitary napkins having a preformed flexible member with a central absorbent hump for close contact with the body and barrier means to intercept fluid migration.

The present invention provides an absorbent article having close contact with the body and improved protection against lateral effusion. Although described below as a sanitary napkin, it is understood that the invention can be adapted for use in disposable diapers, adult incontinence means, training pants and the like where absorption of at least 8 grams of fluid is desired. The sanitary napkin generally includes a liquid permeable cover, a preformed liquid impervious member and an absorbent core located between the cover and the preformed member. The preformed member has a protuberance and a barrier. The protrusion has a vertex that extends over a surface that faces the body of the absorbent core. In a preferred embodiment, the protrusion is longitudinally oriented and more preferably longitudinally oriented and positioned in the middle. The barrier surrounds the periphery of the absorbent core and is adapted to intercept the fluid migrating towards a perimeter of the sanitary napkin. In another preferred embodiment of this invention, the sanitary napkin includes a liquid-permeable cover, a liquid-impervious preformed member, an absorbent core located between the shroud and the preformed member, and a partition layer secured to the pledge surface of the pledget. preformed member. The preformed member has a protrusion with a vertex extending over the surface that gives the body of the absorbent core and a barrier surrounding the periphery of the absorbent core. The barrier is adapted to intercept the fluid that flows towards the perimeter of the sanitary napkin. The protrusion and the partition layer cooperate to form a cavity. Conveniently, the cavity preferably maintains the protrusion facing the wearer's body when lateral forces are exerted on the sanitary napkin during use. This construction provides a sanitary napkin with improved body fit characteristics. Another preferred embodiment of this invention provides a sanitary napkin with a liquid-permeable cover, a liquid-impervious preformed member, a first absorbent core located between the shroud and the preformed member and a partition layer secured to the pledge surface of the pledget. preformed member. The preformed member has a protrusion with a vertex extending over the surface that gives the body of the absorbent core and a barrier surrounding the periphery of the absorbent core. The barrier is adapted to intercept the fluid that migrates towards the perimeter of the sanitary napkin. The barrier has a first spaced wall and a second spaced wall. The dividing layer and the preformed member are coextensive and form a first cavity and a second cavity between the walls of the barrier and the partition layer and the second cavity is the area between the protrusion and the partition layer. The first cavity contains a second absorbent core and the second cavity contains a third absorbent core. The first absorbent core is in fluid communication with the second absorbent core and the third absorbent core through one or more openings in the preformed member close to the first absorbent core. A general aspect of this invention is to provide an absorbent article having improved body contact, as well as improved protection against lateral spillage. A more specific aspect of the invention is to provide an improved sanitary napkin with improved body contact and adjustment components to improve the overall efficiency of the sanitary napkin. Another aspect of this invention is to provide a sanitary napkin with a preformed member that provides intimate contact with the wearer's body, improved lateral spill prevention and is comfortable to use. Another aspect of this invention is to provide a sanitary napkin with a longitudinally oriented protrusion for better body contact and a barrier to intercept the body fluid that migrates towards the outer perimeter of the sanitary napkin.

These and other aspects, features, and advantages are readily apparent when considered in reference to the following specifications and the accompanying drawings, wherein sanitary napkins are illustrated and depicting preferred embodiments of the present invention. It should be understood that the concept of the invention should not be considered limited to the constructions disclosed except as determined by the scope of the appended claims. Fig. 1 is a perspective view of an embodiment of this invention illustrated as a sanitary napkin. Fig. 2 is a cross-sectional view of the sanitary napkin taken along line 2-2 of Fig. 1. Fig. 3 is a perspective view of the preformed member illustrating the protrusion positioned in the middle and the barrier . Fig. 4 is a cross-sectional view of the sanitary napkin taken along line 4-4 of Fig. 1. Fig. 5 is a cross-sectional view of another embodiment of this invention taken along the Y-Y line illustrating a wicking layer that resides on the protrusion. Fig. 6 is a cross-sectional view of another embodiment of this invention illustrating a cavity formed by the protrusion of the preformed member and a liquid-impermeable partition layer.

Fig. 7 is a cross-sectional view of another embodiment of this invention illustrating a plurality of absorbent cores. Referring to the drawings, a disposable absorbent article 10 of the present invention is illustrated in the form of a sanitary napkin. In general, a sanitary napkin is used by a woman to absorb bodily fluids, such as menstruation, blood, urine and other body excreta that have been evacuated during a menstrual period. Although the present invention will be described with reference to a sanitary napkin, those skilled in the art will appreciate that this description is only an example and should not be considered as limiting the scope of the present invention. The present invention will now be described in more detail with reference to the Figures. With reference to Figs. 1-3, the sanitary napkin 10 includes an optional liquid-permeable cover 12, which gives the body, a preformed member 14 impermeable to liquids that gives the garment, an absorbent core 16 between the cover 12 and the preformed member 14. The member preformed 14 has a barrier 18 positioned adjacent the absorbent core 16 and a protuberance 20. The sanitary napkin 10 has a pair of spaced longitudinal edges 22 and 23 and transverse ends 24 and 25, which collectively form the perimeter 26 of the sanitary napkin 10 The sanitary napkin 10 is about 150 millimeters (mm) to 300 mm long and about 50 mm to 175 mm wide at its widest point. The sanitary napkin 10 has an hourglass configuration but may include shapes such as rectangle, oval, race track, dog bone and the like. The sanitary napkin 10 should have a thickness of less than 10 mm but preferably it will vary from a few millimeters to 7 mm and more preferably from 2 mm to 4 mm. The thickness measurement methodology is explained in more detail below. As is usual in the art, the cover 13 is permeable to liquids and is adapted to reside on that side of the sanitary napkin 10 to be in contact with the wearer's body, ie, directionally, which gives the body. The cover 12 can be a flexible, liquid-permeable, non-absorbent material. The cover 12 is provided for comfort and fit and serves to direct the fluid to the underlying absorbent core 16 which retains any evacuated fluid. The cover 12 can be constructed of a woven or non-woven material which is easily penetrated by the body fluid having contact with its surface. Preferably, the cover 12 is made of a material which allows the passage of the fluid without deviating it considerably in a horizontal plane parallel to the cover 12. In addition, the cover 12 should retain little fluid or should not retain any fluid in its structure so as to provide a relatively dry surface next to the skin. Generally, the cover 12 is a simple rectangular sheet of material with a width sufficient to rest on the side facing the body of the absorbent core 16. The cover 12 may be constructed of carded wefts bonded with polyester, polypropylene, polyethylene, nylon, or nylon. other fibers that can be joined by heating. Other polyolefins also work well, such as copolymers of polypropylene and polyethylene, low density polyethylene for lining, finely perforated film webs and network material. Other suitable materials are polymer composite materials and a nonwoven fabric material. Composite sheets are generally formed by extruding polymer onto a web of spun material to form an integral sheet. This material is preferred because the outer fabric surface is not irritating to the wearer's skin and has a cushion feel. Another preferred material for the cover 12 is a spun polypropylene web. The weft can contain about 1 to 6 percent titanium dioxide pigment to give it a clean white appearance. A uniform spun material is convenient because it has sufficient strength, after being punched in the longitudinal direction, to withstand being torn or separated during use. The most preferred polypropylene wefts have a weight between 16 and 40 grams per square meter. Conveniently, the weight is between 20 and 35 grams per square meter. The liquid permeable cover 12 may also contain a plurality of openings (not shown) formed therein. These openings should be sorted by size so that the fluid can pass through the cover 12 and into the absorbent core 16. If desired, the openings can be positioned along a longitudinal central axis X-X of the sanitary napkin 10 or it may be zoned or located in the area proposed to receive body fluid. The openings are for increasing the rate at which bodily fluids can penetrate the absorbent core 16. This helps maintain a significantly drier surface for the cover 12 than when there are no openings. Therefore, while the openings are not essential, a functional advantage is obtained by its use. The liquid-permeable cover 12 can also be treated with a surfactant to make it more hydrophilic and thereby assist in the absorption of the liquid. The surfactant may include local additions or materials internally applied as polysiloxanes. The absorbent core 16 has a surface 28 that faces the body adjacent the cover 12. The absorbent core 16 has an outer periphery 30 located inwardly of the perimeter 26 of the sanitary napkin 10. The cover 12 and the preformed member 14 , in combination, will surround the absorbent core 16. The absorbent core 16 provides a means to absorb the menstrual fluid. The total absorbent capacity of the absorbent core 16 must be compatible with the predetermined exudate load in the proposed use of the sanitary napkin 10. Preferably, the sanitary napkin 10 is adapted to absorb the fluid of a woman with medium to dense flow. In general, the amount of body fluid, including menstruation, is greater than 5 grams. In addition, the size and shape of the absorbent core 16 can be varied. For example, the absorbent core 16 may be in the form of a rectangle, oval or race track. Preferably, the absorbent core 16 has an hourglass configuration. The absorbent core 16 is generally made of one or more materials which, in combination, are substantially hydrophilic, compressible, adjustable and non-irritating to the skin of the wearer. Acceptable materials are well known in the art and include, for example, various natural or synthetic fibers, wood pulp fibers, regenerated cellulose fibers or cotton, or a mixture of pulp and other fibers, meltblown polymer, such as polyester and polypropylene. The absorbent layers may also be comprised of other well-known materials used in absorbent articles, including multiple layers of cellulose filler, rayon fibers, cellulose sponge, hydrophilic synthetic sponge, such as polyurethane and the like. The absorbent core 16 can be a composite of absorbent materials having a density gradient, from low to high, relatively speaking, in the Z direction, as seen in Fig. 1. It has been found that by providing the absorbent core 16 with a density gradient from low to high, a capillary action is produced which draws the fluid deeper into the absorbent core 16 and conveniently away from the cover 12. The absorbent core 16 may contain superabsorbent particles which are effective in the retention of bodily fluids. The superabsorbent particles have the ability to absorb a large amount of fluid in relation to their own weight. Typical superabsorbent particles used in absorbent articles, such as sanitary napkins, can absorb anywhere from 50 to 60 times their weight in body fluids. The protrusion 20 has a base 32 defined by portions of longitudinal sides 34 and 35 and transverse end portions 36 and 37. The protrusion 20 has a vertex 38 which is the most superior surface of the protrusion 20. The vertex 38 is preferably located along the longitudinal center line of the protrusion 20. The absorbent core 16 can cover the protrusion 20, covering the aforementioned side and the end portions 34-37, respectively. However, this is not preferred because the absorbent materials can adversely affect the flexibility and bodily adjustment characteristics of the protrusion 20. It is preferred that the apex 38 extend over the surface 28 that faces the body of the absorbent core 16. This allows the protrusion 20 to rest comfortably adjacent to the wearer's labia majora. In addition, this arrangement improves the movement of bodily fluids that reach the sanitary pad 10 away from the wearer and towards the absorbent core 16. There is also less possibility of the fluid reaching the protuberance 20 again wetting the wearer. This gives the user a greater sensation of dryness. Preferably, the protrusion 20 extends about 1 mm to 10 mm above the body-facing surface 28. The protrusion 20 may be oriented longitudinally and preferably, it is both oriented longitudinally, as centered on the medium along the longitudinal central axis X-X and the transverse axis -Y of the sanitary napkin 10. The term "medium" or " "medial" is used in the present to mean that the transverse end portions 36 and 37 of the protrusion 20 are equidistant from the transverse ends 24 and 25 of the sanitary napkin 10. Consequently, the protrusion 20 does not have to be centered in relation to the longitudinal edges 22 and 23 of the sanitary napkin 10, but it is preferred that the longitudinal axis X-X of the sanitary napkin 10 coincide with the longitudinal center line of the hump 20. The hump 20 can be in any way always and when at least having contact with a portion of the upper lips of the wearer. The protrusion 20 may be asymmetric or symmetrical. Non-limiting examples of suitable configurations for the protrusion 20 include oval, rectangular, square, box-shaped, cylindrical having a plane passing longitudinally from one end to the other and hemispherical, i.e., dome-shaped. The length of the protrusion 20 is measured longitudinally from a transverse end portion 36 of the base 32 to the other transverse end portion 37. The length of the protrusion 20 may vary from 1.5 centimeters (cm) to the length of the absorbent core. 16. Preferably, it is from 2 cm to 12 cm and more preferably from 4 cm to 8 cm. The width is generally measured from a longitudinal side portion 34 of the base 32 to the other longitudinal side portion 35 along the transverse axis Y-Y. The width of the protrusion 20 can vary from 1 cm to 5 cm. It is preferably from 1.5 cm to 4 cm and more preferably from 1.5 cm to 3 cm. The height of the protrusion 20 is the vertical distance H, in the Z direction, from the plane of the base 32 to the plane of the apex 38. The height H of the protrusion 20 is 3 mm to 25 mm. Preferably, it is 3 mm to 20 mm and more preferably 5 mm to 15 mm. The dimensions of the protrusion 20, other than the thickness, are measured using a standard rule without placing any load on the product. It should be understood that the height of the protrusion 20 may be different from the thickness. The thickness will normally be used to express the thickness of the sanitary pad 10 measured from the opposite outer surfaces. For example, with reference to Fig. 2, the thickness of the protrusion 20 at the apex 38 would include the thickness of the preformed member 14 in the protrusion 20 and the cover 12; whereas the height of the protrusion 20 is the vertical distance H from the plane of the base 32 to the plane of the vertex 38. Referring to Figs. 1-4, the outer part of the base 32 is a planar region 40. The planar region 40 extends from the base 32 to the periphery 30 of the absorbent core 16. The planar region 40 is substantially flat and can have 15% a 100% of the absorbent capacity of the absorbent core 16 located in this region. Placing a substantial portion of the absorbent capacity of the sanitary napkin 10 in the planar region 40 extracts fluids which contact the protrusion 20 away from the point of attack and towards the absorbent core 16. This gives the sanitary napkin 10, and in particular to the area of contact with the user's body, a dry and comfortable feeling. The surrounding planar region 40 should have a thickness of less than 10 mm but will preferably vary from a few millimeters to 7 mm and more preferably from 2 mm to 4 mm. The thickness of the planar region 40 can be measured according to the following procedure. All measurements are made on newly unpacked absorbent products. Each sanitary napkin 10 should be removed from its package for at least 30 minutes and handled carefully to avoid compression, or otherwise affect its properties. Unless stated otherwise, all tests are performed at a relative humidity of 50% ± 2% and a temperature of 22.7 ° C (73 ° F) and with a removable strip removed and the adhesive blocked using talc or starch of corn. To expose the planar region 40 for thickness measurement, the sanitary napkin 10 can be cut transversely through the transverse central axis Y-Y, as seen in Fig. 1. Alternatively, cross-cut adjacent to one of the portions of transverse ends 36 or 37 of the protrusion 20 to expose the end area 42 or 43, as seen in Fig. 4. The sanitary napkin 10 can be cut transversely using a device that will not excessively compress the surrounding area, like a knife, scissors, paper cutter and the like. A suitable meter to measure thickness is # 22P-20 available from Federal Products Company of Providence, Rhode Island. This thickness gauge normally has opposite flat circular feet, each with a diameter of 0.64 cm (1/4"), a stroke length of 2.54 cm (1"), meter depth of 5.08 cm (2") and increases 1/1000 * 2.54 cm (1/1000") in your dial. The quadrant meets the specification ANSI # B89.1.10. The spring tension varies from 30 grams (start of stroke) to 60 grams (fully open, end of stroke). The meter is set to zero first. The sample is cut as described above to expose the end area 42 of the planar region 40. Samples should have as many wrinkles as possible before the test. The feet of the meter are separated and the sample is placed between them. The feet of the meter are released and are allowed to meet smoothly in such a way that the feet rest on the opposite outer surfaces of the planar region 40. The sample feet should generally be oriented parallel to the opposite surfaces to obtain a true value of thickness for the planar region 40. The thickness of the planar region 40 absorbent is determined by reading the quadrant 30 seconds after the foot has contact with the sample. Referring to Fig. 4, the barrier 18 surrounds the absorbent core 16 so that the barrier effectively delimits the absorbent core 16. The barrier 18 has an interior wall 44 spaced from an outer wall 46. The walls 44 and 46 are joined together yes to form an inverted "V" or "U" configuration inverted with a more upper portion 48. The inner wall 44 is positioned close to the absorbent core 16 and the outer wall 46 is positioned distally or far away of the absorbent core 16. "Surround" means that the barrier 18 substantially forms a closed circuit or 360 degrees. The width and height of the barrier 18 must be sufficient to allow the barrier 18 to adapt to changes in the contour of the wearer's surface and effectively intercept the migrating body fluid to prevent lateral effusion. These changes are generally attributed to the variable placements of the sanitary napkin 10 in the undergarment and the differences in general physiology of each wearer. The barrier 18 should preferably have a certain height so that the uppermost portion 48 is at least at the level of the plane of the surface 28 that faces the body of the absorbent core 16 at the periphery 30. Preferably, the uppermost portion 48 will extend over the surface 28 that faces the body and more preferably will extend 1mm to 5mm above the body-facing surface 28. Since the barrier 18 will be in contact with the body of the wearer and preferably in the region of the thighs, effectively forming a package between the wearer and the sanitary napkin 10, it is desirable that the barrier 18 be covered by a material that is soft and flexible, like the cover 12.

The cover 12 can be secured to the outer wall 46 of the barrier 18. The method for securing the cover 12 to the barrier 18 and if desired the absorbent core 16, can be a suitable method that does not leave a hard and uncomfortable residue that It would be annoying for the user to leave. The methods for joining the various materials are well known to those skilled in the art and include the use of pressure sensitive adhesives, double-sided tape, sonic adhesion and heat sealing, to name a few. The adhesives, like melted adhesives, can be applied in a uniform manner and as a continuous or non-continuous layer. The preformed member 14 can be made of material with high molecular weight which is impermeable to liquids, flexible and is able to return to its original position even if it deforms. A material mainly composed of degraded polyolefin foam, particularly degraded polyethylene foam, can be used for the preformed member 14. This material can have different physical characteristics and sizes. For example, degraded polyethylene foam can be formed into a sheet with a thickness ranging from 0.5 mm to 5 mm. The strength and flexibility of the preformed member 14 will vary depending on the stiffness of the sanitary pad 10 before the preformed member 14 is incorporated into the article and the use to which it is to be put. The degree of foam varies from 10% to 40% and a density of 0.025 grams / cubic centimeter (g / cc) at 0.1 g / cc. The degraded polyolefin is light and capable of retaining its shape. The material, however, will lose its capacity of conservation of form if its thickness is below 0.5 mm and will have little flexibility and manageability above a certain thickness. It will have little flexibility and ability to preserve shape in a greater degree of foam. This foam can be formed by a known method. A material composed mainly of degraded polypropylene foam (degraded polyolefin) can also be used. The degraded material can also be used if the degradation is done by chemical process or electronic process. The degraded polyethylene foam provides a preformed member 14 impervious to liquids, substantially flexible. The preformed member 14 can have various geometries that vary from a planar or planar shape to an arcuate shape along the longitudinal axis X-X. "Arcuate" means that when the preformed member 14 is placed on a flat or planar surface, at least one of the end areas 42 and 43 will be spaced above the surface. The preformed member 14, when deformed, substantially returns to its original shape. The preformed member 14 of the polyethylene-containing foam is made by known thermal molding processing. For example, the polyethylene foam sheet can be heated to its softening point. The softened material is then placed against a forming mold and vacuum molded into the desired shape. After removing the preformed member 14 from the mold, it is allowed to cool and then cut to the desired dimension. The preferred formula for forming the polymer foam material containing ethylene is identified as Volara Type E which is a degraded ethylene / vinyl acetate acetate copolymer foam. Also suitable for the present invention is a material identified as Volara Type A which is a degraded polyethylene foam. The products are manufactured and sold by Volte, Inc., Lawrence, Massachusetts. Preferably, the formula is prepared in the form of a sheet and has a thickness of about 1 mm to 5 mm, preferably the sheet is about 1 mm to 3 mm thick. The sheet is subjected to thermal molding at a temperature between about 104 ° C (220 ° F) to 149 ° C (300 ° F) to form the preformed member 14 of the foam. An advantage of the sanitary napkin 10 using a protrusion 20 of the above described features and incorporating a barrier 18 is that the protrusion 20 may be less dense, flexible and more comfortable for the wearer. This provides a sanitary towel 10 that is introduced less to the user than previously known or used sanitary napkins that incorporate a hump, extension or raised surface.

Another advantage of the present invention is that the use of the absorbent material is increased by preventing the flow of bodily fluids towards the outer perimeter 26. This gives the absorbent core 16 additional time to absorb body fluid. Referring to Fig. 5, a cross-sectional view of a sanitary napkin 100 showing an alternative embodiment of this invention is illustrated. The sanitary pad 100 includes a liquid-permeable cover 12 that gives the body a preformed member 104 impervious to liquids that gives the garment and an absorbent core 106 positioned between the cover 12 and the preformed member 104. The preformed member 104 has a barrier 108 and a protrusion 110. Absorbent core 106 has a surface 112 that faces the body positioned toward the cover 102 and a surface 114 that gives the garment positioned toward the preformed member 104. The sanitary napkin 100 also includes a wicking layer. 116 positioned adjacent the absorbent core 106. A function of the wicking layer 116 is to distribute the body fluid through a surface of the absorbent core 106, thereby increasing the efficiency of the absorbent core 106. The wicking layer 116 is preferably placed. between the absorbent core 106 and the preformed member 104 and, more preferably, the wicking layer 116 extends above the surface 112 which gives the body and more preferably can cover the protrusion 110 of the preformed member 104. This configuration conveniently extracts fluids having contact with the protrusion 110 to the surface 114 that gives the garment of the absorbent core 106 and away from the cover 102 to provide a drier surface and better utilization of the absorbent capacity. The wicking layer 116 should be classified by size so that it can effectively transport liquids in contact with its surface to the absorbent core 106. Generally, this layer is a few millimeters to the entire surface inside the barrier 108. The layer with wick 116 may be constructed of a material with sufficient capillary activity, or other means, to attract and transport body fluid. The wicking layer 116 may include more than one material with these characteristics. The wicking layer 116 may be comprised of a fibrous material with poor absorption ability. Suitable materials include polyester and rayon blends that have a minimal nature of fluid retention. Other materials may be wefts made of air or carded polyester, rayon, or polypropylene. A preferred material for the wicking layer 116 is a melt blown polypropylene layer having a thickness of 0.6 mm, a weight of about 60 grams per square meter. This material is available from Kimberly-Clark Corporation with offices at 401 North Lake Street, Neenah, Wisconsin. Referring to Fig. 6, a cross-sectional view of a sanitary napkin 200 showing an alternative embodiment of this invention is illustrated. The sanitary napkin 200 includes a liquid-permeable cover 12 that gives the body a preformed member 204 impermeable to liquids that gives the garment and an absorbent core 206 positioned between the cover 202 and the preformed member 204. The preformed member 204 includes a barrier 208 and a protrusion 210. Absorbent core 206 has a body-facing surface 212 facing deck 202. Sanitary pad 200 includes an optional wicking layer 214 similar to that described above positioned adjacent absorbent core 206. The protrusion 210 has a base 216 defined by portions of longitudinal sides 218 and 219 and portions of transverse ends (not shown). The barrier 208 has an inner wall 220 spaced from an outer wall 222. The inner wall 220 is positioned adjacent the absorbent core and the outer wall 222 is positioned distally or away from the absorbent core 206. The walls 220 and 222 are joined together to forming an inverted "V" or inverted "U" configuration with a further upper portion 224. The inner wall 220 of the barrier 208 surrounds the absorbent core 206 to define an outer periphery 226. The barrier 208 must have a certain height so that the uppermost portion 224 is flush with the plane of the surface 212 that faces the body of the absorbent core 206. Preferably, the uppermost portion 224 will extend above the body-facing surface 212 and more preferably, will extend 1mm to 5mm above the body-facing surface 212. The sanitary napkin 200 further includes a liquid-impermeable partition layer 228 secured to at least a portion of the garment-facing surface of the preformed member 204. The partition layer 228 is at least dimensionally sized so that it can be secured to the base 216 of the protrusion 210 and preferably is large enough to be secured to the outer wall 222 of the barrier 208. The protrusion 210 and the partition layer 228 cooperate to form a cavity 230. The cavity 230 is convenient to maintain the protrusion 210 correctly positioned against the upper lips of the user. The cavity 230 provides a cushion feel and adds flexibility to the protuberance 210. The partition layer 228 can allow air or steam to pass out of the sanitary napkin 200 while blocking the passage of body fluids. The partition layer 228 can be any desired material that is impervious to liquids. A good material is a micro-stamped polymer film, such as polyethylene or polypropylene with a thickness of about 0.025 to 0.13 millimeters (0.001 to 0.005 of an inch).

Two-component films can also be used, as well as woven and non-woven fabrics which have been treated to render them impermeable to liquids. Referring to Fig. 7, a cross-sectional view of a sanitary napkin 300 showing an alternative embodiment of this invention is illustrated. The sanitary pad 300 includes a liquid-permeable cover 302 that gives the body a preformed liquid-impermeable member 304 that gives the garment and a first absorbent core 306 positioned between the cover 302 and the preformed member 304. The preformed member 304 includes a barrier 308 and a protrusion 310. The absorbent core 306 has a body facing surface 312 facing the cover 302. The sanitary napkin 300 includes an optional wicking layer 314 similar to that described above positioned adjacent the absorbent core 306. boss 310 has a base 316 defined by longitudinal side portions 318 and 319 and transverse end portions (not shown). The barrier 308 has an inner wall 320 spaced from an outer wall 322. The inner wall 320 is positioned adjacent the first absorbent core and the outer wall 322 is positioned distally or away from the first absorbent core 306. The walls 320 and 322 are joined between yes to form an inverted "V" or "U" configuration inverted with a more upper portion 324. The inner wall 320 of the barrier 308 surrounds the first absorbent core 306 to define an outer periphery 326. The barrier 208 must have a height similar to the one described above. The sanitary towel 300 further includes a liquid-impermeable partition 328. The partition layer 328 wraps around the garment facing surface of the preformed member 304 and is secured to the base 316 of the protrusion 310 and the outer wall 322. Preferably the partition layer 328 is secured to an exterior surface 330 of the barrier 308 A second absorbent core 332 is positioned between the protrusion 310 and the partition layer 328. A first opening 334 or more in the protrusion 310 allows the body fluid having contact with the protrusion 310 to be absorbed in the second absorbent core 332. first openings 334 may reside above surface 312 that gives the body, down, or some intermediate position. A third absorbent core 336 is positioned in a grooved area 338 formed between the inner wall 320, the spaced outer wall 322 and the partition layer 328. A second opening 340 or more in the inner wall 320 allows the body fluid to be in contact with the inner wall 320 is absorbed in the third absorbent core 336. The second opening (s) 340 may reside above the surface 312 that faces the body, down, or some intermediate position. Preferably, the second opening (s) 340 reside below the surface 312 that faces the body. This allows the communication of liquids between the third absorbent core 336 and the first absorbent core 306 through a second opening 340 or more. By providing the sanitary towel 300 with a second absorbent core 332 and a third absorbent core 336, the total absorbent capacity of the sanitary napkin 300 is increased without substantially adding load. The second absorbent core 332 and the third absorbent core 336 are converted into liquid containment compartments for sudden spills of body fluid, further improving the utilization of the absorbent capacity. In addition, due to the flexibility of the preformed member 304, the second absorbent core 332 and the third absorbent core 336 add a degree of stiffness in specific areas without compromising the comfort and adaptability of the sanitary napkin 300 to conform to the wearer's body. The sanitary napkin 300 of the present invention may be provided with adhesive strips 342 applied to the garment-facing side of the partition layer 328. The adhesive strips 342 are longitudinally positioned but avoiding the area superimposed by the protrusion 310 so that the adhesive does not interfere with the performance of the boss 310. Generally, the adhesive is a pressure-sensitive adhesive capable of securing the sanitary towel 300 to the crotch portion of an undergarment, still allowing removal of the underpants lining when soiled. The adhesive strips 342 are generally covered by a release liner (not shown) such as a Kraft paper that is covered with silicone. In use, the wearer removes the release liner and adheres the sanitary towel 300 to the inner surface of the undergarment. The adhesive strips 342 allow the sanitary towel 300 to remain in position to receive the evacuated liquids. Various alternative modalities of sanitary napkins which may be provided with a medial protrusion and barrier are shown and described in U.S. Patent Number 5,219,341 published by Serbiak et al. On June 15, 1993, U.S. Patent Application Serial Number 08 / 263,178 filed June 21, 1994 in the name of Couture-Dorschner et al. And U.S. Patent Application Serial No. 08 / 058,249 filed May 12, 1993 in the name of Hirt et al. The statements of all patents and disclosed herein are hereby incorporated by reference herein and become a part thereof. While 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 invention. Therefore, it is intended to encompass in the appended claims all changes and modifications that are within the spirit and scope of this invention.

Claims (24)

1. CLAIMS An absorbent article having an outer perimeter and adapted to be used adjacent to a wearer's body, the absorbent article comprising: a) a liquid-impervious preformed member and b) an absorbent core secured and superimposed on a portion of the preformed member, the absorbent core having a surface that gives the body and the preformed member having a protuberance with a vertex that extends above the surface that gives the body, the preformed member further having a barrier means to intercept the body fluid that migrates towards the outer perimeter, the barrier means surrounding the absorbent core.
2. The absorbent article according to claim 1 wherein the absorbent core has an outer periphery and the barrier means has a height at least equal to the surface that it gives to the body of the absorbent core at the outer periphery.
3. The absorbent article according to claim 1 or 2 wherein the preformed member has a predetermined arcuate shape along the longitudinal axis.
4. The absorbent article according to one of the preceding claims wherein the preformed member is a thermoformable flexible polyolefin.
5. 5. The absorbent article according to the claim 4 wherein the polyolefin is a degraded foam.
6. 6. The absorbent article according to claim 5 wherein the polyolefin foam is polyethylene foam.
7. 7. The absorbent article according to the claim 5 wherein the polyolefin foam is polypropylene foam.
8. The absorbent article according to one of the preceding claims wherein the preformed member has a thickness between 0.5 mm to 3 mm.
9. The absorbent article according to one of the preceding claims further comprising: c) a liquid permeable cover positioned adjacent the body-facing surface and d) a wicking layer located between the absorbent core and the preformed member.
10. The absorbent article according to claim 9 wherein the wicking layer extends above the surface that faces the body of the absorbent core.
11. 11. The absorbent article according to one of the preceding claims, the absorbent article further comprising a liquid permeable cover.
12. The absorbent article according to claim 11 wherein the absorbent core has a predetermined thickness of less than 5 mm and is positioned between the cover and the preformed member.
13. The absorbent article according to one of the preceding claims, further comprising a liquid impermeable barrier layer secured to a portion of a pledge surface of the preformed member where a cavity is formed between the protuberance and the layer divide.
14. The absorbent article according to one of the preceding claims wherein the preformed member is a flexible thermoformable degraded polyolefin foam.
15. 15. The absorbent article according to one of claims 13 or 14 wherein the protrusion has a base and the partition layer is secured to the base.
16. 16. The absorbent article according to one of claims 14 or 15 wherein the polyolefin foam is polyethylene foam with a thickness of 0.5 mm to 3 mm.
17. The absorbent article according to one of the preceding claims wherein the barrier means has an inner wall and a spaced outer wall joined together with a further upper portion, the uppermost portion extending over the body-facing surface.
18. 18. The absorbent article according to one of claims 13 or 17 wherein the dividing layer extends through a surface that gives the garment of the preformed member and is secured to the outer wall.
19. 19. The absorbent article according to one of the preceding claims having a longitudinal central axis and the protuberance is oriented longitudinally in relation to the axis.
20. The absorbent article according to one of the preceding claims wherein the protrusion is positioned in the middle along the longitudinal central axis.
21. The absorbent article according to one of the preceding claims wherein the absorbent core covers the entire preformed member except an upper portion of the protrusion and the barrier means.
22. 22. An absorbent article having an outer perimeter and adapted to be used adjacent to a user's body, especially according to one of the preceding claims, the absorbent article comprising: a) a liquid permeable cover; b) a preformed member impervious to liquids; c) a first absorbent core positioned between the cover and the preformed member, the first absorbent core having a body-facing surface and the preformed member having a protrusion with a vertex extending above the body-facing surface, the member preformed further having a barrier means for intercepting the body fluid migrating towards the outer perimeter, the barrier means having an inner wall and a distally spaced outer wall joined together; d) a liquid impermeable barrier layer secured to a portion of the surface that gives the garment of the preformed member and e) a second absorbent core positioned between the protrusion and the partition layer, the partition layer having an opening for liquid absorption in the second absorbent core.
23. 23. The absorbent article according to claim 22 further comprising a third absorbent core positioned between the inner wall, the spaced outer wall and the partition layer, the inner wall having a second opening for absorption of liquids in the third absorbent core. .
24. 24. The absorbent article according to claim 23 wherein the second opening is positioned below the surface that faces the body of the first absorbent core.