MXPA06009818A - Pantiliner - Google Patents

Abstract

A sanitary napkin comprising a fluid permeable topsheet, a fluid permeable backsheet, and an absorbent core disposed therebetween is disclosed. The sanitary napkin can be a pantiliner. The absorbent core comprises relatively hydrophilic material defining a core outer periphery. The topsheet and the backsheet comprise relatively hydrophobic nonwoven material, at least one of the topsheet and the backsheet defining a sanitary napkinouter periphery that is substantially larger than the core outer periphery. The area between the core outer periphery and the sanitary napkin outer periphery is a breathable zone. The sanitary napkin further comprises a fluid impermeable barrier between the backsheet and the absorbent core, the fluid impermeable barrier being disposed within the core outer periphery.

Description

PANT1PROTECTOR FIELD OF THE INVENTION This invention relates to disposable absorbent devices and, more particularly, to devices intended for use by women, such as sanitary napkins, pantiliners and the like.

BACKGROUND OF THE INVENTION Women or sanitary towels, mainly during menstrual periods, to receive and contain menstrual fluids, as well as other vaginal emissions, in order to protect their clothes and not dirty them. The sanitary napkins usually have an adhesive attachment means for adhering the device to the crotch region of the wearer's undergarment, usually to their panties. Pantiprotectors have the same purpose as sanitary napkins; the difference is mainly and the total size, including the first one. Pantiprotectors are, in general, less bulky and are designed to protect the wearer's clothing against relatively small amounts of vaginal emissions. Many women have adopted the habit of using an absorbent device between menstrual periods to protect their clothing from any vaginal discharge, including a mild discharge of urine and, sometimes, anal discharge. Due to the fact that a sanitary napkin is usually very bulky for constant use, users usually use pantiliners. Most pantiliners have a non-permeable backing layer, commonly called a bottom canvas. The lower canvas of the typical pantyhose can, for example, be a polymeric film impervious to liquids. A waterproof layer prevents liquids absorbed inside the device from getting wet or wetting the user's clothes. However, the liquid impervious layer also causes the pantiprotector to become hot and uncomfortable, due to moisture trapped in the absorbent core. Pantiprotectors are also known to provide a permeable backing layer, such as a permeable polymeric film or a nonwoven fabric weft backing layer. In general, these backing layers are liquid impervious and vapor impermeable layers that allow the exchange of steam, while preventing the wearer's clothes from becoming soiled. For example, U.S. Pat. no. 4,059,114 issued to Richards on November 22, 1977, presents a disposable garment protection having a moisture barrier sheet made of a blown microfiber web that is impervious to liquids but permeable to vapor. Also US patents no. 4,681, 587, granted to Anderson et al. on July 21, 1987 presents an absorbent article, for example, a pantiprotector provided with at least one ventilation area that allows the passage of steam and provides cooling and drying effects, so it is more convenient to use this pantiprotector. While these permeable pantiliners are responsible for providing some improvement over the more common waterproof pantiliners, comfort, garment dirt, dryness and vapor exchange (permeability) remain key design issues. Consequently, absorbent devices have been sought that offer better retention and absorption of liquids, while allowing the most efficient passage of the vapor.

BRIEF DESCRIPTION OF THE INVENTION A sanitary napkin is presented which includes a liquid-permeable top sheet, a liquid-permeable bottom sheet and an absorbent core located therebetween. The sanitary napkin can be a pantiprotector. The absorbent core contains relatively hydrophilic material that defines the outer periphery of the core. The upper canvas and the lower canvas contain relatively hydrophobic nonwoven fabric material, of which, at least one of them, the upper canvas or the lower canvas, defines the outer periphery of the sanitary napkin which is substantially larger than the periphery external core The area between the outer periphery of the core and the outer periphery of the sanitary napkin is a permeable zone. The sanitary napkin also contains a liquid impervious barrier between the lower canvas and the absorbent core, the liquid impermeable barrier is located within the outer periphery of the core.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 shows a perspective view in partial section of a pantiprotector of the present invention. Figure 2A is a cross-sectional view according to cross-section 2-2 of one embodiment of a pantyhose as shown in Figure 1. Figure 2B is a cross-sectional view according to cross-section 2-2 of another embodiment of a pantiprotector as shown in Figure 1.

DETAILED DESCRIPTION OF THE INVENTION A preferred embodiment of an absorbent article of the present invention, a sanitary napkin, which may be a panty-protector 10, is shown in a perspective view partly in section in Figure 1 and in cross section in Figures 2a and 2b. While the invention is disclosed in the particularly p-referred form of a panty-protector, it can also be considered that the invention described is a sanitary napkin and all the following descriptions, which refer to the panty-protectors, can also be sanitary napkins, in where the difference is rather deduced than that of type. The invention may also be a device for adult incontinence, a pad for anal emissions, an interlabial pad or the like. The pantiprotector has two end regions 12 and 14 and a mid region 16. The panty protector 10 has a side 15 facing the body, which is in contact with the wearer's body and a side 17 facing the garment, which is in contact with the inner surface of the wearer's undergarment. The side 17 oriented towards the garment may have, therein, a pressure sensitive adhesive (not shown) for attaching it to the undergarment of the wearer. Normally, this adhesive is covered with a detachable strip, which is removed before fixing in the underwear article. While the pantiprotector 10 can have any shape known in the industry, the preferred form is usually that of an "hourglass", which narrows towards the center from a relatively greater transverse width in the portion of one of the extreme regions to a relatively smaller transverse width in the middle region. The transverse width is defined, generally, as the dimension perpendicular to the dimension, which is defined as longitudinal, going from the end region 12 to the end region 14 parallel to the longitudinal centerline L. The pantiprotector may also have extensions lateral, known in the industry as "wings" or "fins" (not shown) intended to extend and cover the elastic of the panty in the crotch region of the wearer's undergarment. "The pantiprotector 10 has an absorbent core 20 that absorbs and stores the body fluids emitted during its use. The absorbent core 20 may be fabricated from any of the materials well known to persons of ordinary skill in the industry. Examples of materials of this type include multiple sheets of creped cellulose wadding, fluffed cellulose fibers, wood pulp fibers, also known as air felt, textile fibers, a mixture of fibers, a fiber mass or fluff, a weft of polymeric fibers and a mixture of polymeric fibers. In a preferred embodiment, the absorbent core 20 is relatively hydrophilic. The term "relatively hydrophilic" means that the core 20 is hydrophilic with respect to the portion of the sanitary napkin 10 in the permeable zone (described below), which is relatively hydrophobic. The hydrophilicity can be determined using any of several means known in the industry, including, as a reference, the contact angles of a liquid on a surface. However, what is important in the present invention is a relative hydrophilicity, such that the surface tensions in the towel / liquid system tend to drive the liquid deposited in the sanitary napkin to the absorbent core 20. In a preferred embodiment, the absorbent core 20 is relatively thin, less than about 2 mm thick, preferably, less than about 1 mm and, more preferably, less than about 0.5 mm thick. The absorbent core may contain absorbent gelling materials (MGA), including MGA fibers. In one embodiment, the absorbent core 20 is an air-laid cellulose material having a basis weight of about 50 grams per square meter to about 100 grams per square meter. In one embodiment, the absorbent core has 63 grams per square meter (60 grams per square meter laid to air + 5% by weight of AGM in the form of fiber), available from Concert GmbH, Germany, with the designation VH063.200.B001 . In another embodiment, the core may be a non-woven, carded, airlaid material having a basis weight ranging from about 50 grams per square meter to about 100 grams per square meter. In one embodiment, the absorbent core is a non-woven web laid to the carded web of 80 grams per square meter, comprising 2.2 hydrophilic polypropylene dtex fibers and 10 superabsorbent dtex fibers, available from Sandler under the name Sawabond 24-00-32. The absorbent core 20 is cut with a shape, whose outer edges define the periphery 30 of the core. The shape of the absorbent core 20 can be, in general, rectangular, circular, oval, elliptical or the like. The absorbent core 20 may, in general, be centered with respect to the longitudinal center line L and the transverse center line T. In order to provide a certain degree of softness and vapor permeability to the side of the pantyhose 10 oriented towards the garment, a vapor permeable outer layer, referred to herein as a lower canvas 22, is provided adjacent to the absorbent core 20 and on the garment-facing side of the absorbent core 20. The lower canvas 22 can be fabricated from any known vapor-permeable material in the industry. The lower canvas 22 can be a microporous film, a film formed with holes or another polymeric film which is vapor permeable or which becomes vapor permeable, as is known in the industry. A preferred material is a smooth, smooth, compliant and permeable liquid and vapor permeable material, such as a woven or knitted fabric. A weave of non-woven fabric provides softness and adaptability for comfort, and produces a low amount of noise, so that movement does not cause any undesirable sound. In a preferred embodiment, the lower canvas 22 is a nonwoven web having a basis weight between about 20 grams per square meter and about 50 grams per square meter. In one embodiment, the bottom sheet is a non-woven web of thermally relatively hydrophobic consolidated filaments of 4 denier polypropylene fibers, available from Fiberweb Neuberger under the name of F102301001. To provide softness in contact with the body, the panty-protector 10 may have a body-facing layer, referred to herein as the upper canvas 26. The upper canvas 26 may be made of any soft, smooth, compliant and porous material that is comfortable in contact with human skin and through which vaginal emissions can pass. The upper canvas 26 may contain fibrous webs of non-woven fabric, in addition to containing fibers known in the industry, including bicomponent and shaped fibers. E n m odality, the non-woven fabric of thermally relatively hydrophobic consolidated filaments of 15 grams per square meter comprising bicomponent fibers of the sheath-core type (PP / PE) available from Pegas as, Czech Republic, under the name of 10XXN008005 . In a preferred embodiment, both the upper canvas 26 and the lower canvas 22 are hydrophobic and liquid permeable nonwoven webs. If it is hydrophobic, or becomes hydrophobic, such that a drop of liquid forms a contact angle of at least about 75 degrees with respect to the surface of the screen, the non-woven fabric can be repellent to liquids, functioning as well as a barrier against liquids, nevertheless it is, in fact, permeable to liquids.

At least one, and preferably both the upper canvas 26 and the lower canvas 22, define a shape whose edge defines the outer periphery 28 of the pantiprotector. In a preferred embodiment, both the upper canvas 26 and the lower canvas 22 define the outer periphery 28 of the pantiprotector (or sanitary napkin). The two layers can be cut with a die, for example, after combining all the components in the structure of the pantiprotector, as described herein. Sandwiched between the absorbent core 20 and the lower canvas 22 is a barrier layer 24 impervious to liquids. The barrier layer 24 prevents the fluids retained by the absorbent core 20 from penetrating the pantiprotector and soiling the adjacent garments. However, unlike the products of the prior industry, the barrier layer 24 does not extend to the outer periphery 28 of the panty-protector 10. Rather, the barrier layer does not extend laterally beyond the periphery 30 of the core. In a preferred embodiment, the barrier layer 24 completely covers the garment-facing side of the absorbent core 20, but does not extend beyond the periphery 30 of the core. In a preferred embodiment, the absorbent core 20 does not extend laterally outward to the same extent as the upper canvas 26 or the lower canvas 22, but the outer periphery 28 of the sanitary napkin is substantially larger than the outer periphery 30 of the core. . In this way, the region of the pantiprotector 10 between the periphery 30 of the core and the outer periphery 28 of the sanitary napkin defines a permeable zone 32 that contains only the upper canvas and / or the lower canvas 22. In a preferred embodiment, the permeable 32 extends laterally from the periphery 30 of the core to the outer periphery 28 of the sanitary napkin, including it. A minimum level of permeability is obtained thanks to the use of porous non-woven fabric materials in the upper canvas and / or in the lower canvas. If the permeable zone contains both the upper canvas and the lower canvas, it may also contain a means for joining them, such as an adhesive means, including hot-melt adhesives. In an embodiment of this type, the adhesive must be applied in a manner that makes the upper canvas and / or the lower canvas non-porous in its entirety. In one embodiment, the adhesive is applied to the permeable zone in a series of coils. A benefit of having a permeable zone between the periphery 30 of the absorbent core and the outer periphery 28 of the sanitary napkin is that it allows the user's underwear to be covered more efficiently without increasing the overall volume of the article. That is, by concentrating the absorbent core 20 in a relatively small central region of the sanitary napkin, the volume is reduced. By having a permeable and hydrophobic region surrounding the absorbent core, the garment-facing side of the lower canvas 22 of the sanitary napkin has a larger surface area available for the adhesive bond with which it will be attached to the undergarment. In one embodiment, the absorbent core 20 is located symmetrically with respect to the longitudinal centerline L, although placed more towards either the first end region 12 or second end region 14. In this way, it may be intended, for example, more of the permeable zone 32 to the anal region of the user. The largest longitudinal dimension of the sanitary napkin 10, measured parallel to the longitudinal axis L, may be at least about 6 cm, or at least about 10 cm, or at least about 15 cm, or at least about 20 cm, or even at least about 25 cm, or more, to cover the anal region of the body, in addition to the vaginal region. The largest width dimension of the sanitary napkin 10, measured parallel to the transverse axis T, can be at least about 3 cm, or at least about 6 cm, or at least about 10 cm. In a preferred embodiment, the sanitary napkin 1 0 has, in general, an hourglass shape, with a minimum width dimension of approximately 5 cm in the middle part and a maximum width dimension in the end regions of approximately 6.5 cm and a longitudinal dimension of approximately 15 cm. The maximum surface area (i.e. the area of the sanitary napkin when viewed in a flat view) of the sanitary napkin 10 and the absorbent core 20 is limited only by the intended use, including the relative size of the wearer's underwear. . For use as a panty-protector, the sanitary napkin can cover an area of at least about 60 cm 2, or at least about 75 cm 2, preferably at least about 90 cm 2 and can have at least about 100 cm 2. In the same way, the absorbent core 20 can cover an area of at least about cm2, or at least about 25 cm2, or at least about 35 cm2 and may have at least about 45 cm2 or more. In one embodiment, the permeable zone 32 represents at least about 25% of the total surface area of the sanitary napkin. The permeable zone may represent at least about 35%, 40%, 50%, 75% or 90% of the surface area of the sanitary napkin. In one embodiment of a pantiprotector of the present invention, the absorbent core 20 has a surface area of about 32 cm2 and the permeable zone has a surface area of about 50 cm2, for a total surface area of about 20 cm2. of the pantiprotector of approximately 82 cm2. All components can be joined by means of adhesives, including hot melt adhesives, as is known in the industry. The adhesive can be the Findlay H2128 UN and the Savare 'PM 17 can be applied using the Dynafiber HTW system. As mentioned above, the only requirement is that the adhesive used in the permeable zone does not cause the water to become impermeable, so that the upper canvas or the lower canvas will not become not porous Other benefits of preserving the porosity of the permeable zone include preventing the sanitary napkin from sticking to the wearer's skin, which would thereby increase discomfort. In a preferred embodiment, both the upper canvas 26 and the lower canvas 22 have surfaces facing the body, which are either hydrophobic or hydrophobic. The term hydrophobic means that a drop of water placed on the surface does not easily wet the nonwoven fabric or penetrate it. In one embodiment, the hydrophobic surface facing the body is repellent to liquids, such that a drop of water placed thereon remains on the surface for a prolonged period of time, for example, 10 to 30 minutes. In one embodiment, the permeable zone 32 contains both the upper canvas 26 and the lower canvas 22, but the upper canvas has a very low basis weight, such that, although it is relatively hydrophobic, the liquid deposited on the upper canvas portion which covers the relatively hydrophilic absorbent core 20 is easily attracted through the upper canvas towards the absorbent core. However, the liquid deposited outside the region covering the absorbent core, ie, in the permeable zone 32, is not absorbed and does not penetrate through the garment-facing side of the panty-protector 10. Therefore, during use, the pantiprotector 10 of the present invention is a comfortable, flexible and very thin pantiprotector having a relatively small hydrophilic "pocket" and located in the center, surrounded by a permeable liquid repellent zone 32. The relatively hydrophobic permeable zone acts as an effective barrier against the movement of the liquid away from the region of the absorbent core 20. In this way, during use, the liquid emitted by the body can be rapidly absorbed and prevented from flowing out of the body. pantiprotector towards the user's clothes. In a preferred embodiment, the impermeable zone 32 completely surrounds the absorbent core 20. That is, in no portion of the panty protector 10 the periphery of the core 30 coincides with the periphery of the sanitary napkin 28, but the two peripheries are always separated by a region of permeable zone 32. In this embodiment, permeable zone 32 is a continuous band of permeable zone that completely surrounds or surrounds the absorbent core 20. In order to promote the more rapid entry of liquid into the absorbent core 20, the upper canvas 26 and lower canvas 20 can be processed so as to have a certain amount of fiber entanglement. The entanglement can be achieved using the mechanical means known in the industry. For example as shown in the cross section of Figure 2B, the absorbent core 20 and the upper canvas 26 can be entangled by etching, so that the fibers of the upper canvas 26 are forced into fibers of the absorbent core 20. Other means, including the mechanical processing means known in the industry, such as that which, in general, is referred to as "winding in". ring ", can also be used to achieve fiber entanglement. It is thought that treatments that induce the deformation of fibers, such as etching, help not only to expose the liquid deposited to the hydrophilic fibers of the absorbent core, but also form "hills" and "valleys" on a small scale. which help to contain the liquid deposited in the pantiprotector on the "pocket" of the hydrophilic absorbent core 20. All documents cited in the Detailed Description of the Invention are, in their relevant part, incorporated herein by reference, the citation of any document should not be understood as an admission that it is prior industry with respect to the present invention. While particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. It has been intended, therefore, to cover all the changes and modifications within the scope of the invention in the appended claims.

Claims (10)

1. CLAIMS 1. A sanitary napkin comprising a fluid-permeable top sheet, a fluid-permeable bottom sheet, and an absorbent core disposed therebetween, wherein, a. The absorbent core comprises relatively hydrophilic material that defines the outer periphery of the core; b. the upper canvas and the lower canvas comprise relatively hydrophobic nonwoven fabric material, of which at least one of them, the upper canvas or the lower canvas, defines the outer periphery of the sanitary napkin; c. The sanitary napkin further comprises a fluid-permeable barrier between the lower canvas and the absorbent core; characterized in that, d. the outer periphery of the sanitary napkin is substantially larger than the outer periphery of the core, the area between the outer periphery of the core and the outer periphery of the sanitary napkin is a permeable zone, and the liquid impermeable barrier is located within the periphery external core The sanitary napkin according to claim 1, further characterized in that at least the upper canvas and the lower canvas have sufficient hydrophobicity to make them repellent to fluids. 3. The sanitary napkin according to claim 1 or 2, further characterized in that the upper canvas and the lower canvas have a common external periphery. 4. The sanitary napkin according to any of the preceding claims, further characterized in that the periphery of the fluid impermeable layer coincides with the outer periphery of the core. 5. The sanitary napkin according to any of the preceding claims, further characterized in that the upper canvas and the core are joined by a mechanical interlacing of a portion of their respective fibers. The sanitary napkin according to any of the preceding claims, further characterized in that the outer periphery of the core defines a general oval shape. 7. The sanitary napkin according to any of the preceding claims, further characterized in that the periphery of the sanitary napkin defines a general hourglass shape. 8. The sanitary napkin according to any of the preceding claims, further characterized in that the sanitary napkin is a pantiprotector. 9. A sanitary napkin comprising a fluid-permeable top sheet, a fluid-permeable bottom sheet, and an absorbent core disposed therebetween, further characterized by: a. The core to bsorbent comprises relatively hydrophilic non-woven fabric laid in the air, which includes fibrous MGA and defines the outer periphery of the core; b. the upper canvas and the lower canvas comprise relatively hydrophobic material of non-woven fabric with thermally bonded filaments; The upper canvas and the lower canvas define the outer periphery of the sanitary napkin, which is larger than the outer periphery of the core; c. The sanitary napkin further comprises a fluid impervious barrier between the lower canvas and the absorbent core; characterized in that: d. the area between the outer periphery of the core and the outer periphery of the sanitary napkin is a permeable zone that completely surrounds the outer periphery of the core, such that the vapors can permeate completely through the sanitary napkin in the permeable zone; and the fluid permeable barrier is disposed adjacent the absorbent core and within the outer periphery of the core. 10. A thin absorbent pantiprotector comprising a fluid-permeable top sheet, a fluid-permeable bottom sheet, and an absorbent core disposed therebetween, further characterized in that a. The absorbent core has a basis weight of approximately 50 grams per square meter and 100 grams per square meter, the absorbent core comprises relatively air-tight hydrophilic non-woven material having at least about 5% by weight of AGM fiber content and defining a outer core periphery; b. the upper canvas and the lower canvas comprise relatively hydrophobic material of nonwoven fabric of thermally consolidated and liquid repellent filaments, the upper canvas and the lower canvas define the outer periphery of the pantiprotector, which is larger than the outer periphery of the core; c. The sanitary napkin also comprises a liquid impermeable barrier located between the lower canvas and the absorbent core, characterized in that: d. the area between the outer periphery of the core and the outer periphery of the pantiprotector is a permeable zone that completely surrounds the outer periphery of the core, such that the vapors can completely permeate through the panty-protector in the permeable zone; and the fluid impermeable barrier is a polyethylene film disposed adjacent the core and within the outer periphery of the core.