MXPA99010345A - Sanitary towel with rear extension that provides a liquid blocking function - Google Patents

Abstract

The present invention relates to a sanitary napkin having a liquid absorption section with two opposite longitudinal sides, a first transverse side defines a front portion of the liquid absorption section and a second transverse side is opposed to the first transverse side and defines a back portion of the liquid absorption section, the liquid absorption section includes a liquid permeable cover layer, a liquid impermeable barrier layer and an intermediate absorbent layer to the cover layer and the barrier layer; The towel further includes a liquid collection section attached to the liquid absorption section, the liquid collection section projecting backward from the second transverse side of the liquid absorption section at a distance sufficient to cover at least partially a gluteal groove of the user when the liquid absorption section is affected aligned with the user's vaginal orifice, the liquid collection section has an external surface that faces away from the wearer's body when the article is being worn by the wearer, the outer surface being substantially free of adhesive; The liquid collection has a preferred fold region extending longitudinally such that when the article is used by the user, at least a portion of the liquid collection section is able to bend in the preferred fold area in a manner that such that it enters or adapts to the glute groove of the user

Description

SANITARY TOWEL WITH BACK EXTENSION THAT PROVIDES A LIQUID LOCK FUNCTION FIELD OF THE INVENTION The present invention relates to an article for absorbing exudate material from the body, very particularly to a sanitary napkin capable of reducing the likelihood of runoff at the trailing end, particularly at night when the wearer adopts a horizontal posture.

BACKGROUND OF THE INVENTION Traditional sanitary napkins, when used at night, are prone to malfunction in the posterior end area, because the menstrual fluid tends to flow under the effect of gravity towards the buttocks. (This problem occurs less frequently during the day when the user is standing, since in that position, gravity causes the menstrual fluid to penetrate through the cover layer of the towel and migrate to the absorbent layer where it is permanently withheld). To limit the occurrence of improper operation at night, manufacturers have developed specially designed sanitary napkins that offer improved absorption capacity at the rear end. Specifically, said towels are made longer and somewhat wider to offer a larger surface area that captures the menstrual fluid. The theory on which this proposal is based is that the free fluid that could have traveled through the user's body or through the cover layer, to the buttocks area of an article, that had not been absorbed in an article designed to Use during the day, would be absorbed in the later extension of an article designed for use during the night. Thus, the possibilities of malfunction are reduced. Although sanitary napkins made for overnight use are less frequently malfunctioning at the back end compared to sanitary napkin designs made for daytime use, there are still some cases of malfunction at night. One problem is that the exudate material that will be absorbed can flow along the cover layer of the towel in the space created by the wearer's glute groove. Conventional towels do not solve this problem as they have all been designed to lie relatively flat against the body. In addition, conventional sanitary napkins have adhesive on the back end of their surface facing the garment. This adhesive, among other things, will generally hold the towel firmly in the undergarment and prevent the sanitary napkin from conforming to the shape of the buttocks (eg, the gluteal groove) in that region of the body. Another drawback with conventional sanitary products for use at night is their potential for comfort below ideal.

With this respect, at least for some consumers, the presence of a long posterior extension creates a perception of a product that is excessively bulky, less comfortable, and impractical to place in an intimate garment. In addition, from a manufacturing point of view, conventional designs for overnight use, although effective, have a higher cost production than designs for daytime use because more raw materials are needed to perform the later extension. According to the above there is a need in the industry for developing a sanitary napkin that offers improved protection against the improper functioning of the posterior end, particularly when the user adopts a horizontal posture. There is also a need to develop a sanitary napkin designed for overnight use that is more comfortable to use and also less expensive to manufacture than traditional sanitary napkins designed for overnight use.

OBJECT AND BRIEF DESCRIPTION OF THE INVENTION Therefore, it is an object of the present invention to provide an improved sanitary napkin designed for use at night.

Another object of the present invention is to provide a sanitary napkin designed for overnight use better adapted than conventional designs to conform to the wearer's body in the back portion of the towel, particularly with respect to the gluteal groove. A further object of the present invention is to provide a sanitary napkin designed for overnight use that makes more efficient use of the material and absorbent capacity. Yet another object of the present invention is to provide a towel designed for overnight use that is relatively less expensive in its manufacture than conventional towel designs for use at night. Therefore, as widely described herein, the present invention provides a sanitary napkin, comprising: (A) a liquid absorption section for absorbing the exudate material from the body, said liquid absorption section having: (i) ) two opposite longitudinal sides; (I) a first transverse side defining an anterior portion of said liquid absorption section; (Ii) a second transverse side opposite the first transverse side, the second transverse side defining a rear portion of said liquid absorption section; (iv) an imaginary longitudinal centerline; (v) an imaginary transverse centerline; said liquid absorption section comprises: (i) a liquid permeable cover layer, said cover layer having an external surface facing the wearer's body when the towel is being used by the wearer; (ii) a liquid permeable barrier layer, said barrier layer having an external surface facing away from the wearer's body when the towel is being used by the wearer; (Ii) an absorbent layer between the cover layer and the barrier layer; (V) adhesive material on the external surface of the barrier layer, the adhesive material capable of releasably adhering the liquid absorption section to an intimate garment of the wearer when said towel is being used; (B) a liquid collection section attached to said liquid absorption section, said liquid collection section projecting back from the second transverse side of said liquid absorption section at a distance sufficient to at least partially cover the groove gluteus of the user when the liquid absorption section is substantially aligned with the vaginal orifice of the wearer, the liquid collection section having an external surface that faces away from the wearer's body when the article is being used by the user. user, the outer surface being substantially free of adhesive material.

Liquid Absorption Section In the context of the present invention, the liquid absorption section is somewhat analogous to the main body of a standard sanitary napkin not for overnight use. It is the part of the towel that lines up with or covers all or a large part of the user's vaginal orifice. Therefore, it is preferred that the liquid absorption section of the towel is generally rectangular in shape with rounded ends. When the article has said shape, the first and second transverse sides are the shorter opposite sides and will generally have an arched shape. The first transverse side defines an anterior portion of the liquid absorption section, ie the portion of the liquid absorption section which, when the towel is in use, normally lies on the front (front side) of the body of the liquid. the user. Opposed to the first transverse side is the second transverse side. The second transverse side defines a posterior portion of the liquid absorption section, ie the portion of the absorption section of the liquid which, when the towel is in use, normally lies on the rear (back) side of the body of the liquid. the user. The first and second longitudinal sides are the opposite sides longer and will generally be straight or slightly arched. Nevertheless, it should be understood that the shape of said sides is not essential in the invention, and therefore the transverse or longitudinal sides may be arched or straight. It is also not essential that the liquid absorption section be generally rectangular, since the articles that have a liquid absorption section in the form of a square, parallelogram or any other polygon, or even the shape of an oval, hourglass or dog bone, are within the scope of the present invention. In such a case (ie, when the liquid absorption section is not rectangular), the longitudinal sides of the liquid absorption section will be considered as opposite sides of a relatively longer length as compared to the other opposite sides of the main body. When such a determination is possible, any opposite pair of sides can be considered as the longitudinal sides, or in the limit, opposite portions of any two sides can be considered as the longitudinal sides. For most sanitary napkins, the longitudinal center line of the towel is an imaginary line extending longitudinally along the middle portion of the towel that is equidistant from the longitudinal sides thereof. Therefore, you will divide the towel into two halves, usually in a mirror image. Thus, when the towel is used by the wearer, the longitudinal centerline thereof is generally parallel to, or lies in, the sagittal plane of the wearer. Similarly, for most towels, the transverse centerline is an imaginary line that extends transversely through the article, and is typically, but not always, equidistant from the transverse sides thereof. The transverse center line is therefore perpendicular to the longitudinal center line. When the article has wings (as described later), the transverse centerline is the line perpendicular to the longitudinal center line that divides the wings. The liquid absorption section preferably comprises at least three distinct layers joined together in a superimposed relationship. However, this is not limited to towels that have liquid absorption sections that only have three layers. There are many additional layers and / or other structures that may also be present, all within the scope of the present invention. The layer that is normally in contact with the wearer's body when the towel is being used conventionally is known as the cover layer or topsheet. The main purpose of the cover layer is to allow the rapid entry of the exudate material so that it is absorbed in the towel, thus providing dryness and comfort to the wearer of the towel. The cover layer has two main surfaces, an external surface (i.e., a surface that does not face another layer of the towel) that faces the wearer's body when the towel is in use, and an inner surface that looks towards the absorbent layer. The absorbent layer is under the cover layer. The absorbent layer may comprise a single layer or a composite layer by combining multiple layers or additional layers. Preferably it is combined with other layers and / or structures, most preferably a transfer layer, to form a complete absorbent system. The main purpose of all these structures is to absorb and retain the material exuded from the body, or to facilitate this procedure. The absorbent layer has two main surfaces, both of which are internal surfaces, that is, they both look towards other layers of the towel. The first surface faces towards the cover layer, the second surface faces towards the barrier layer. Beneath the absorbent layer is the barrier layer or backsheet. The main purpose of the barrier layer is to prevent the exudate material absorbed inside the towel from coming out of the towel on the opposite side from the one that was absorbed. ThusIt is highly preferable that the barrier layer be impermeable to liquids. It is also preferable, for some applications, that the barrier layer be gas impermeable. The barrier layer has two main surfaces, an external surface facing the wearer's undergarment when the towel is being used, and an inner surface facing an absorbent layer. Located on the surface facing the intimate garment of the barrier layer is adhesive material to releasably adhere the liquid absorption section to the wearer's undergarment. In the context of the present specification, it is preferred that the adhesive material employed be capable of firmly securing the liquid absorption section to the undergarment so that when the towel is used, the liquid absorption section does not peel off from the intimate garment without intervention of human. There are many conventional adhesive materials that can be used to perform this function; A simple chemical adhesive is preferred.

The cover layer and the barrier layer are preferably bonded together around the periphery of the article to form a seal enclosing the absorbent layer, and forming a structurally integral towel. It is preferred that this seal surrounds the absorbent layer, and therefore contain it therein. All conventional ways of sealing and / or joining various layers are within the scope of the present invention.

Liquid collection section Attached to, and projected laterally from the rear of the liquid absorption section when the towel is in the flat state, there is a liquid collection portion. There is no particular form essential for the liquid uptake portion. Normally, the liquid uptake portion will be a natural extension of the liquid absorption section, ie it will be a continuation of the same general shape. The liquid collection section extends beyond the second transverse side of the liquid absorption portion at a distance sufficient to at least partially cover the gluteal groove of the wearer when the absorbent section is substantially aligned with or covering the orifice vaginal of the user. The exact length of the liquid collection section, or the distance to which it extends beyond the second transverse side of the liquid absorption section, will depend on the length of the liquid absorption section and the size of the user. . For example, when the length of the absorbent section is around about 24 cm, the length of the liquid collection section is at least 2.5 cm, preferably at least 3.75 cm, and most preferably at least 5.0 cm, and still most preferably at least 7.0 cm. The extension length of the liquid collection portion is measured along the collinear line with the longitudinal centerline of the towel, from the second transverse side of the liquid absorption section to the physical posterior end (transverse end) of the liquid collection section. Furthermore, although it is not essential, it is preferred that the liquid collection section have a width (ie, its measurement taken in a direction perpendicular to its length) of at least 7.0 cm, in order to cover a significant portion of the gluteal groove of the user. The liquid collection section can comprise a single layer of material or a structure composed of sheets. In any case it is joined with the liquid absorption section, preferably in one of the two ways. In one form, the liquid collection section is not continuous with any of the component layers of the liquid absorption section. Instead, the liquid collection section is manufactured separately from the liquid absorption section and then attached in such a manner that it extends to the rear of the liquid absorption section as a separate entity. In such cases, the second transverse side of the liquid absorption section is a physical end of that section. Normally, the liquid collection section joins the liquid absorption section in an overlapped relationship. In the overlap zone, both sections are joined together by any conventional means, for example, bonding by adhesive, thermal bonding, etc. In contrast, in the second and very preferred form, the liquid collection section is continuous with, and is an integral extension of, one or more of the component layers of the liquid absorption section. The liquid collection section can be continuous with the barrier layer of the liquid absorption section, the cover layer of the liquid absorption section, or preferably both. Additional continuous or non-continuous materials may also be presented with those of the liquid absorption layer. In any mode, the liquid collection portion will have two external surfaces, a first external surface facing the wearer's body (specifically at least a portion that will look toward the wearer's buttocks and gluteal groove) when the towel is used. It will also have a second external surface facing the user's undergarment. The external surface of the liquid acquisition portion facing the user's undergarment is substantially free of adhesive material. Preferably, there is a complete absence of adhesive material on this surface. The absence of adhesive material will allow the liquid collection portion to better conform to the wearer's buttocks since it will not remain adhered to the wearer's undergarment. Due to the natural moisture in this area of the body, it is possible that, in the absence of being adhered to the wearer's undergarment, the liquid uptake portion will naturally adhere slightly to the wearer's skin, causing the take the outline of the body in that area, reducing the likelihood of runoff of material exuded by the glute groove. To assist in this function, ie the assumption of the liquid collection section of the shape of the buttocks, including the gluteal groove, the section preferably is provided with a preferred longitudinally extending fold area. "Longitudinally" means that the zone extends in a direction parallel to, and most preferably comprises, the collinear line with the longitudinal center line of the liquid absorption section. When located in this region, the area will be, in most users of the towel, registered with the gluteal groove of the user. By "preferential folding zone" it is intended to say that the liquid collection section preferably will bend within this area before bending in other areas. The preferred bending zone is preferably constructed, if possible, so that the section preferably be bent inward in front of the wearer's body (in contrast to bending outward, away from the wearer's body). In this way, because the liquid collection section is free of adhesive, and therefore is free to separate from the undergarment, when it does this, it will preferably penetrate into the gluteal groove. Thus, the section will be better adapted to the body of the user of this region, further reducing the risk of improper functioning.

The preferred longitudinally extending fold zone can be formed in a variety of conventional ways.

Preferably the materials comprising the liquid collection section are mechanically superior in the region corresponding to the bend zone. Most preferably, the liquid collection section of the sanitary napkin is free of any absorbent system. Therefore, any absorption capacity available in the liquid collection section is present due to the low absorption capacity of the cover layer and also to the thin volume that may exist between the part of the cover layer and the part of the barrier layer, and that is able to capture and retain the liquid. In practice, however, the absorbent capacity of the liquid collection section is lower compared to the absorption capacity of the liquid absorption section. In a possible variant, the liquid collection section can be provided with an increased absorption capacity. When this is the case, it is highly preferred that the average absorption capacity of the liquid collection section is less than the average absorption capacity of the liquid absorption section. The reduction of the absorbent capacity in the liquid collection section will normally result in a reduction in manufacturing costs. Therefore, only the minimum amount of absorption capacity required for the particular application should be present. The ratios of: 2: 1, 3: 1, and 5: 1 (absorbent capacity of liquid absorption section to absorbent capacity of liquid collection section) are highly preferred. It is possible to provide the liquid collection section with an increased absorption capacity by extending in that first section one of the component layers of the absorption system of the liquid collection section. For example, if the absorbent system includes a transfer layer and an absorbent layer, the transfer layer can be extended in the liquid collection section. The degree of extension may vary according to the specific application. One possibility is to make the portion of the transfer layer that enters the liquid collection section substantially coextensive with the part of the cover layer and the part of the barrier layer. Another possibility is to extend the transfer layer only partially in the liquid collection section. In another embodiment, a gradient of absorption capacity can be created along the sanitary napkin by providing the liquid collection section with an absorbent system whose absorption capacity is progressively reduced toward the back end of the sanitary napkin. In practice, this can be achieved by producing the absorbent system of the sanitary napkin so that the part containing the liquid collection section has a progressively reduced width (gauge). Contrary to what conventional wisdom dictates, such reduction (or complete absence) in the absorbent capacity of the liquid collection section does not create any significant increase in subsequent malfunction. This is due to the fact that only a small fraction of the total liquid discharge reaches the liquid collection section and a lower absorption capacity is sufficient. In examples where the liquid collection section has virtually no absorption capacity, the liquid-impermeable nature of the material in that section prevents the liquid from coming into contact with the undergarment and therefore is sufficient to avoid an inappropriate operating event. . Although the liquid may stagnate locally, the small amount of liquid that often accumulates develops sufficient surface tension with the cover layer so that the liquid is retained to the towel without escaping and staining the undergarment. It is also preferable that the flexibility of the liquid collection section along the transverse axis is greater than the flexibility of the liquid absorption section also measured along the transverse axis. In this way, the liquid collection section will be able to easily conform to the shape of the wearer's body in the gluteal region. Normally, a reduction in the absorption capacity of the liquid collection section (as compared to the liquid absorption section) increases the flexibility of said section, so no further efforts are necessary in this respect. The ratios of 2: 1, 3: 1, and 5: 1 (flexibility of the liquid uptake section to the liquid absorption section) are highly preferred.

It is also preferable that the average gauge of the liquid capture section be smaller than the average gauge of the liquid absorption section. The reduced size, together with the increased flexibility, will generally improve the molding of the liquid collection section compared to the back sections of the sanitary napkins designed in the prior art for use during the night.

The ratios of 2: 1, 3: 1, and 5: 1 (gauge of liquid absorption section to gauge section of liquid capture) are highly preferred. Furthermore, the present inventor has also discovered that an increase in the flexibility and comfort of the liquid collection section allows the section to behave as a positioning system improving the stability of the sanitary napkin in the perineal area of the wearer. As mentioned above, an increase in the flexibility of the liquid collection section allows the portion of the sanitary napkin to better adapt and follow the anatomy of the wearer in the buttock area. Said enhanced adaptation results in greater contact in the area of the sanitary napkin / skin with the result that the towel does not change position, and better maintain a fluid barrier.

Preferably, a sanitary napkin of the present invention further comprises a pair of wings, a wing projecting from each longitudinal side of the liquid absorption section, preferably intermediate and spaced from the transverse sides of the section. The wings are flexible and are capable of bending at an edge of the crotch portion of the wearer's undergarment when the towel is being used. The wings may be of conventional design, although an isosceles trapezoidal wing with the upper part attached to the longitudinal side of the main body and the base at the distal end is preferred. In use, the wings help to stabilize the towel in the intimate garment and protect the lateral ends of the intimate garment from blemishes. The wings are preferably continuous integral extensions of the materials of the cover layer and barrier layer of the liquid absorption section sealed together. However, they may comprise separately formed material attached to the liquid absorption section after the manufacture thereof. They may also be formed from a panel projected outwardly from the longitudinal side of the liquid absorption section that has been adhered to the intimate garment facing surface, as described in the commonly assigned co-pending international patent application published as WO. 98/27903 in the name of Boulanger et al. Other objects and features of the invention will be apparent by reference to the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The following is the description by a preferred embodiment, with reference to the following drawings, in which: Figure 1 is a top plan view of a sanitary napkin constructed in accordance with the present invention, showing the cover layer partially peeled to show the transfer layer, the absorbent layer, and the barrier layer; Figure 2 is a perspective view of the sanitary napkin of the present invention of curved shape, typical of what would be when the sanitary napkin is placed in the wearer's undergarment; Figure 3 is a bottom plan view of the sanitary napkin of Figure 1; Figure 4 is a sectional view taken on line 4-4 of Figure 1; Figure 5 is a sectional view of an alternative embodiment characterizing a liquid collection section where the transfer layer of the liquid absorption section extends; Fig. 6 is a sectional view of an alternative embodiment characterizing a single layer absorbent system having a glue element extending toward the liquid collection section;Figure 7 is a side view of the sanitary napkin according to the present invention that is shown attached to the wearer's undergarment (the undergarment is illustrated in sectioned lines); Figure 8 is a top plan view of another embodiment of the present invention wherein the liquid collection section is discontinuous with the liquid absorption section; Figure 9 is a sectional view taken on line 9-9 of Figure 8; Figure 10 is a sectional view taken on line 10-10 of Figure 8. In the drawings, preferred embodiments of the invention are illustrated by way of example. It is important to mention that the description and drawings are granted for purposes of illustration and as an aid to understanding, and do not attempt to define the limits of the invention.

DESCRIPTION OF A PREFERRED MODALITY With reference to Figures 1 and 2, the preferred embodiment of the present invention is shown, of a female sanitary napkin 20. The towel 20 comprises two sections, a liquid absorption section 22 and a liquid collection section 24.

Liquid Absorption Section The liquid absorption section 22 has a first transverse side 26 defining a front portion thereof and a second transverse side 28 defining a posterior portion thereof. Each of these sides is concavely arched. The first transverse side 26 is a physical edge of the towel 20 and the liquid absorption section 22; the second transverse side 28 is not. In the present embodiment, the second transverse side 28 is considered as the seal of the periphery 52. The liquid absorption section 22 also has a first longitudinal side 30 and a second longitudinal side 32, each longitudinal side being substantially straight. An imaginary longitudinal center line 34 goes from the central portion of the liquid absorption section 22, equidistant from the longitudinal sides 30, 32. Projected laterally outward from each of the longitudinal sides 30 and 32, there is a wing 38, 40 (respectively). The wings 38, 40 are in the form of an isosceles trapezoid with the upper part attached to the longitudinal side and the base at the distal end. The liquid absorption section 22 also has an imaginary transverse center line 36 perpendicular to the longitudinal center line 34 and which simultaneously divides the wings 38, 40. The liquid absorption section 22 is of laminar construction and preferably comprises a layer of liquid. fluid permeable cover 42, an absorbent system 44, and a fluid impervious barrier layer 50. Each of these layers is described in detail below.

Coating layer Coating layer 42 can be a relatively low density, bulky, very bulky, non-woven material. The cover layer 42 may be composed of a single type of fiber, such as polyester or polypropylene or it may be composed of conjugated fibers or bi-components having a low melting point component and a high melting point component. The fibers can be selected from a variety of natural and synthetic materials such as nylon, polyester, rayon (in combination with other fibers), cotton, acrylic fiber and the like, and combinations thereof. One example is the nonwoven cover layer supplied by STEARNS of sanitary napkins sold by Johnson & Johnson Inc. of Montreal, Canada under the trade name Stayfree Ultra-Thin Cotton Dry Cover. The bi-component fibers can be made of a polyester layer and a polyethylene sheet. The use of appropriate bi-component materials results in a non-woven fuse fabric. Examples of such fusible fabrics are described in the U.S.A. No. 4,555,446 published November 5, 1995 to Mays. Using a meltable cloth increases the ease with which the cover layer can be mounted to the adjacent transfer cover and / or to the barrier layer. The cover layer 42 preferably has a high degree of wettability, although the polymers comprising the individual fibers comprising the cover are not particularly hydrophilic. The roofing material should also contain a large number of relatively large pores. This is because the cover layer 42 must rapidly absorb the body fluid and transport it away from the body and towards the point of deposition. Preferably, the fibers that form the cover layer 42 should not lose their physical properties when they are wetted, or in other words, should not collapse or lose their flexibility when subjected to water or body fluid. The cover layer 42 can be treated so that the fluid passes directly through it. The cover layer 42 also functions to transfer fluid rapidly to the other layers of the absorbent structure 44. Therefore, the cover layer 42 is preferably wettable, hydrophilic and porous. When composed of synthetic hydrophobic fibers such as polyester or bicomponent fibers, the cover layer can be treated with a surfactant to impart the desired degree of wettability. Most preferably, the cover layer 42 is made of a polymer film having large pores. Due to its high porosity, the film achieves the function of rapidly transferring body fluid to the inner layers of the absorbent system. Open co-extruded films such as the RETICULON ™ brand, for example, described in the U.S.A. 4,690,679 and available in sanitary napkins sold by Johnson & Johnson Inc. of Montreal, Canada are useful as cover layers in the present invention.

The cover layer 42 can be included with the rest of the absorbent system 44 to help promote fluid transport by fusing the cover with the next layer.

Absorbent System - Transfer Layer Adjacent to the cover layer 42 on its inner side and attached to the cover layer 42 is a fluid transfer layer 46 which forms part of the absorbent system 44. The transfer layer 46 provides the means to receive the body fluid from the cover layer 42 and retain it until the extremely dense absorbent layer has the opportunity to absorb the fluid. The transfer layer 46 is preferably more dense and has a greater proportion of pores smaller than the cover layer 42. These qualities allow the transfer layer 46 to contain the body fluid and retain it away from the outer side of the layer. cover 42, thereby preventing the fluid from re-wetting the cover layer 42 and its surface. However, it is preferable that the transfer layer 46 is not so dense in order to prevent fluid from passing through the layer 46 towards the absorbent layer 48. The transfer layer 46 may be composed of fibrous materials, such as pulp of wood, polyester, rayon, flexible foam, or the like, or combinations thereof. The transfer layer 46 may also comprise thermoplastic fibers for the purpose of stabilizing the layer and maintaining its structural integrity. The transfer layer 46 can be treated with a surfactant on one or both sides in order to increase its wettability, although generally the transfer layer 46 is made of relatively hydrophilic materials and does not require treatment. The transfer layer 46 is preferably bonded on both sides to the adjacent layers, ie the cover layer 42 and the absorbent layer 48. An example is the material made of non-woven wood pulp mixed with a binder sold by Buckeye Technologies of Memphis, Tennessee under the VICELL 6002 assignment.

Absorbent layer - Absorbent layer Immediately adjacent and attached to the transfer layer 46 is the absorbent layer 48. The absorbent layer 48 is preferably an extremely dense layer having a fine porosity. It has a great capacity for liquid retention and is extremely retentive. Most preferably, the absorbent layer 48 is composed of compressed sphagnum moss material. More specifically, the sphagnum moss is formed as a board by air or layer succession and wet calendering to obtain a structure similar to a relatively thin sheet, i.e. from about 0.025 to 0.25 cm thick, relatively dense, i.e. of about 0.2 at 1.0 g / cm3. The structure may include a layer of Kraft laminate fabric on one or both surfaces of the sphagnum moss layer preferably a fibrous component is mixed with the sphagnum moss material. The fibrous component is suitably a natural or synthetic textile fiber such as rayon, polyester, nylon, acrylic or the like, having an approximate length of 0. 625 to 3.75 cm and a denier of about 1.0 to 5. The fibrous component may be present in an amount of about 2 to 20% by weight, most preferably 4 to 8%. The absorbent layer 48 may also comprise other components such as wood pulp, synthetic wood pulp, thermomechanical pulp, mechanically ground pulp, polymers, surfactants, superabsorbents and the like. In an alternative embodiment, the absorbent system 44 includes a single layer of absorbent pulp material (the transfer layer is omitted). Absorbent layer 48 preferably comprises an absorbent pulp material and includes other absorbent materials or nonabsorbent materials that help stabilize the absorbent structure such as conjugate fibers, fusible fibers, binders, sphagnum peat moss particles, superabsorbents, and the like and combinations thereof. them, and optionally may include other absorbent or non-absorbent or non-absorbent materials that help stabilize the absorbent structure, such as conjugate fibers, fusible fibers, binders, sphagnum moss peat particles, superabsorbents, and the like and combinations thereof.

Barrier layer Beneath the absorbent system 44 is a barrier layer 50 comprising a liquid impervious film material to prevent liquid entrapped in the absorbent layer 46 from exiting the sanitary napkin and staining the wearer's undergarment. Most preferably, the barrier layer 50 is made of polymeric film, such as polyethylene, which is inexpensive and can be easily disposed thereon. The polyethylene is capable of completely blocking the passage of the liquid or gas emanating from the absorbent system 44. In a variant, the breathing films can be used allowing the passage of gases, but blocking the liquid. A suitable example is a combination of polyethylene / ethylene vinyl acetate (EVA) film sold by Edison Plastics Company in Canada and in the United States under the designation XP-1167B. The cover layer 42 and the barrier layer 50 are joined at the marginal portions to form an enclosure that holds the absorbent system 44 captive. Bonding can be accomplished by means of adhesives, heat bonding, ultrasonic bonding, radio frequency sealing, mechanical shirring, and the like and combinations thereof. The peripheral sealing line is shown in figure 1 with the reference number 52. With reference to figures 2 and 3, in order to improve the stability of the sanitary napkin, the intimate facing surface of the barrier layer 50 of the fluid absorption section 22 is provided with adhesive material 58, typically hot melt adhesive material capable of establishing a temporary bond with the undergarment material.

A suitable material is the composition designated HL-1491 XZP commercially available from H.B.Fuller Canada, Toronto, Ontario, Canada.

The adhesive 58 can be applied to the intimate facing surface of the barrier layer 50 of the fluid absorption section 22 in various patterns, including full coverage of adhesive, parallel longitudinal lines, a line of adhesive following the perimeter of the adhesive. the structure, transverse lines of adhesive or the like. A standard release paper 82 (shown only in Figure 3) covers the adhesive 58 before the towel is used to prevent the towel from adhering to itself or to foreign objects. The release paper is of conventional construction (eg, wet laid Kraft wood pulp covered with silicone) and suitable papers are available from Tekkote Corporation (Leonia, New Jersey, E.U.A.) and have the designation FRASER 30 # / 61629.

Liquid collection section Attached to the liquid absorption section 22 is the liquid collection section 24. The liquid collection section 24 is a thin and flexible rear extension of the liquid absorption section 22., able to conform to the area of the user's buttocks. The liquid collection section 24 appears as a natural extension of the liquid absorption section 22, and therefore its longitudinal sides 72, 74 generally appear as extensions of the longitudinal sides 30, 32 of the liquid absorption section 22. Similarly, the curvature at its transverse end 70 is similar to that of the first transverse side 26 of the liquid absorption section 22 (however, such a shape is preferred without being essential to the present invention). In the preferred embodiment shown in Figures 1 and 2, the liquid collection section 24 projects from the liquid absorption section 22 approximately 7.0 cm (ie its projection length 62 is approximately 7.0 cm). The projection length 62 of the liquid collection section 24 is the maximum distance that exists between the second transverse side 28 of the liquid collection section 22 and the transverse side 70 of the liquid collection section 22 (including the width of seal 60, if any), measured along a line parallel to the longitudinal center line 34 of the liquid absorption section 22. The liquid collection section 24 also has a width 76 of approximately 7.0 cm; the width 76 of the section 24 being the distance from one longitudinal side 72 of the section 24 to the other 74, measured along a line perpendicular to the line together with which the projection length 62 is measured, through the midpoint of it. With reference to Figure 4, the liquid collection section 24 is a double layer structure comprising a cover layer portion 54 that is continuous (and integrally formed) with the cover layer 42 of the liquid absorption section. 22. Both the cover layer portion 54 and the cover layer 42 are formed of the same material. (optionally, the portion of the cover layer 54 of the liquid collection section 24 may contain a non-woven fabric to reduce what some users may perceive as a hot, sticky plastic sensation, preferably a combination of a cover may be used. plastic with non-woven material in the liquid collection section 24). The liquid collection section 24 also comprises a part of barrier layer 56 which is continuous (and integrally formed) with the barrier layer 50 of the liquid absorption section 22. Both the part of the barrier layer 56 and the Barrier layer 50 are formed of the same material. The part of the cover layer 54 is secured to the part of the barrier layer 56 along a sealing line 60 of the periphery generally in the U-shape. Therefore the seal of the periphery 52 (in the region of the second transverse end of the liquid absorption section) and seal line 60 define the liquid collection section 24 in the present modality. No portion of the absorbent system 44 extends into the liquid collection section 24, as well as any additional independent absorbent material (except for the portion of the absorbent cover layer 54). Therefore, the liquid collection section 24 has a reduced absorbent capacity and reduced gauge as compared to the liquid absorption section 22. The difference in caliber between the liquid absorption section 22 and the liquid collection section 24 resulting from the absence of absorbent material in the liquid collection section 24 is clearly shown in Figure 4. The average absorption capacity ratio of the liquid absorption section 22 to the average absorption capacity of the layer of liquid collection 24 is at least 2: 1. Similarly, the ratio of liquid absorption layer gauge 22 to liquid collection layer gauge 24 is at least 2: 1. The flexibility ratio of the liquid absorption layer 22 to the flexibility of the liquid catchment layer 24 is at least 1: 2 The exact values for each of these characteristics and relationships can be determined using the techniques described in the section entitled "Test procedures". With reference to Figure 3, the garment facing surface of the barrier layer portion 56 of the liquid collection section 24 contains no adhesive material 58 as the garment facing surface of the barrier layer 50. of the liquid absorption section 22. The liquid collection section 22 therefore does not adhere to the undergarment 66 when the towel 20 is in use and can be adapted and molded to the wearer's body. Each of the characteristics of the liquid collection section 24, that is to say its projection length 62 to cover at least a portion of the gluteal groove of the wearer, its lack of adhesives on its surface facing the undergarment, its Reduced gauge and its increased flexibility along a transverse axis, helps to allow this part of the sanitary napkin 20 to better conform to the buttock area. Said improved molding increases the comfort potential of the product.

In addition, the perception of conformation by the user can also be improved because the users in practice tend to associate comfort with the reduced width of the product. Another advantage that results from these characteristics is the ability of the liquid collection section 24 to be pumped as a positioning system, keeping the sanitary towel 20 in place towards the perineal region of the wearer. This feature also reduces the possibility of malfunction that can result from a poorly positioned sanitary napkin or have changes in the position of the sanitary napkin. Contrary to what conventional knowledge dictates, a reduction in the absorption capacity in the posterior portion of the sanitary napkin does not result in a greater inadequate performance in that region. The present inventor has observed that most of the fluid discharge from the vaginal orifice is captured by the absorption section of the liquid 22, while only a small fraction is directed to the liquid collection section 24. In most of the In some cases, the absence of absorbent material in this region is enough to hold the menstrual fluid in place. This is due to the high surface tension developed between the liquid and the part of the cover layer 54. Therefore, although the liquid is not absorbed into the sanitary napkin as it would be when the liquid is discharged onto the absorption section of the liquid 22, there is sufficient fluid retention in the liquid collection section 24 to keep the liquid in place and avoid soiling the user's undergarment. At the same time, a number of benefits of the flexibility gained and the reduction of width in the area of the liquid collection section 24 are obtained. Figure 5 illustrates in cross-section another embodiment of the present invention. This embodiment has a liquid collection section 24 containing a portion of a transfer layer 64. The transfer layer portion 64 is (although not necessary) continuous with the transfer layer 46 of the liquid absorption section 22. The part of the transfer layer 64 of the liquid collection section 24 is substantially coextensive with the part of the cover layer 54 and the part of the barrier layer 56. The only area of the liquid collection section 24. where the coextensive relationship is not maintained is the seal of tab 60. One possible advantage of this embodiment is the provision of improved absorption capacity in the liquid collection section 24 which may be useful for applications where sanitary napkins they can undergo a large volume input. However, the disadvantage is an increase in caliper and a reduction in the flexibility of the liquid collection section 24 which can have a negative impact on the comfort potential and the ability to mold of the sanitary napkin 20 to the anatomy of the user. Said negative impact is minimal in practice because the part of the transfer layer 64 is thin and sufficiently flexible. Figure 6 illustrates in cross-section a further embodiment of the invention. This embodiment shows a single-layer absorbent system 44 having a tail element 68 projecting in the liquid collection section 24. The tail element 68 has a thickness that decreases little by little toward the rear end of the towel sanitary 20. This provides the towel 20 with an absorption profile such that the absorption capacity decreases along the longitudinal center line 34 of the product as it moves towards the rear end depending of course on the dimensions of the glue element 68. at any particular point. Each of the above-described embodiments of the sanitary napkin 20 is manufactured in a conventional manner in accordance with conventional techniques. Specifically, a laminar structure is formed, sometimes referred to as a band. This laminar structure comprises an expansion of the materials from which the towel will be created. That is, the laminar structure comprises an expansion of material of the cover layer below the material of the transfer layer, which is on the material of the absorbent layer, all this on an expansion of material of the barrier layer. Some of the materials are not necessarily continuous within the laminar structure, and in that case, they are placed precisely one with respect to the other, in the relationship they will have in the final products. The cover layer material and the barrier layer material are joined together by applying pressure in the appropriate positions, and this creates what will become the seal of the periphery (the seal can also be made by means of heat bonding, ultrasonic bonding, radiofrequency sealing, mechanical shirring, and the like and mixtures thereof). The sealed structure is cut by conventional means (i.e. cut by die, cut by fluid jet, or by laser) from the web to create a discrete article. The adhesive material is applied to the barrier layer in the appropriate positions, and the release paper is applied to cover the adhesive. Alternatively, the adhesive, or the adhesive and release paper may be applied to the web before the individual articles are compressed therefrom. During use, the release paper is removed, and the towel is placed in the wearer's undergarment. Figure 7 illustrates the sanitary towel 20, placed on the undergarment 66 shown in dashed lines. The sanitary napkin 20 is shown in the position it would have when the undergarment 66 is in use, pulled so that its crotch portion presses toward the wearer's perineal area. In this position the liquid absorption section 22 of the sanitary napkin 20 covers at least in part the vaginal orifice of the wearer. The liquid collection section 24 of the sanitary napkin 20 extends over at least a portion of the buttock area. As mentioned earlier in this specification, the buttock area is defined as the sitting portion of the body that extends up the anal opening toward the lower posterior portion. This liquid collection section 24 will conform to the shape of the wearer's body in the gluteal region, and will therefore act to prevent runoff at the posterior end, particularly when the wearer is in a horizontal position. The collection section of the liquid 24 will also help to position the towel as described above. Another embodiment of the present is shown in Figure 8. In this embodiment, the liquid absorption section 22 and the liquid collection section 24 are discrete components with a physical demarcation line 80 therebetween. The liquid absorption section 22 in this embodiment is generally similar to that described above along with other embodiments, and is manufactured in a similar manner. With reference to Figure 9, the liquid collection section 24, however, simply comprises a single layer of the impermeable material from which the barrier layer 50 is constructed. The collection section of the liquid 24 is cut independently of a band. of material and is attached by adhesive (or other conventional means) to the liquid absorption section 22 after the manufacture of that section. The liquid absorption section 22 contains a preferred bending area in the form of a score line 78. The score line 7 is collinear with the longitudinal center line 54 of the liquid absorption section 22. With reference to the figure 10, the score line 78 is such that when the towel 20 is in use the liquid collection section 24 will preferably fold into the gluteal groove of the wearer. This preferential folding will increase the capacity of section 24 to act as a positioning system, as described above.

PROOF PROCEDURE Caliber The procedure consists of measuring the caliber of the material at a pressure of 0.0035 kg / cm2 with one meter of compression using a foot of 5.08 cm in diameter (ASTM D-1777). In the case of the embodiment illustrated in Figure 1, two measurements will be sufficient to establish the caliber relationship between the liquid absorption section 22 and the liquid collection section 24. Note that the measurements made in the absorption section of liquid 22 should be within the seal of the periphery 52. For the modalities where the thickness of a specific section is not constant, several measurements should be made and the results should be added. Said situation will arise in the case of the embodiment illustrated in FIG. 6 where the thickness of the liquid collection section 24 decreases progressively towards the transverse end 70. A possible method is to divide the liquid collection section 24 into a unit area. and measure the thickness of each unit, calculate and then average the results. The average value will constitute the caliber value associated with the section.

Flexibility / lateral stability The purpose of this test is to determine the lateral flexibility of an absorbent product or a portion of an absorbent product holding the sample to lateral compression. The test procedure will be described with reference to Figure 6. The lateral flexibility of the sample is obtained by placing the sample between two Plexiglas curves (simulating the wearer's crotch). The stationary curve is attached to a compression load cell in an Instron unit and a speed of 500 millimeters per minute is imparted to the moving curve. The sample is placed securely between two curves with three metal support rods that go from the stationary curve and are slidably received in the moving curve. The force required to compress the sample at 2.54-cm is recorded. In the case of the embodiments shown in Figures 4 and 5, lateral flexibility is obtained by cutting each sample at its limits by separating the liquid absorption section 22 and the liquid collection section 24. Each sample is subjected to the test procedure and the respective flexibility value is recorded. It is important to note that each sample is placed on the instrument so that a longitudinal axis is perpendicular to the direction of movement of the moving curve.

Absorptive capacity The average absorption capacity of the liquid absorption section and the liquid collection section is established by measuring the total absorption capacity of each section by any standard procedure (the test uses a satisfactory "GATS" measuring instrument ) and dividing the total capacity value for said section by the surface area of the section to obtain an average capacity value expressed in terms of capacity per unit of surface area. The applications of the product and methods of the present invention for health uses or other uses of health care can be achieved by any method and technique of sanitary protection with, incontinence, medical and absorbent such as those present or known to the experts in the art. technique. Therefore, it is intended that the present application cover the modifications and variations of this invention taking into account that they come within the scope of the appended claims and their equivalents.

Claims (22)

NOVELTY OF THE INVENTION CLAIMS

1. - A sanitary napkin comprising: a) a liquid absorption section for absorbing the exudate material from the body, said liquid absorption section having: (i) two opposite longitudinal sides; (ii) a first transverse side defining a front portion of said liquid absorption section; (iii) a second transverse side opposite the first transverse side, the second transverse side defines a posterior portion of said liquid absorption section; (iv) an imaginary longitudinal center line and (v) an imaginary transverse center line; said liquid absorption section comprises: (i) a liquid permeable cover layer, the cover layer having an external surface facing the body of a wearer when the towel is in use by the wearer; (ii) a liquid impervious barrier layer, the barrier layer having an external surface away from the wearer's body when the towel is in use by the wearer; (iii) an absorbent layer intermediate to the cover layer and to the barrier layer; (V) Adhesive material on the outer surface of the barrier layer, the adhesive material being able to releasably adhere the liquid absorption section to an intimate garment of the wearer when the towel is in use; (v) a liquid collection section connected to said liquid absorption section, said liquid collection section projecting back from the second transverse side of said liquid absorption section at a distance sufficient to cover at least one groove gluteus of the user when the liquid absorption section is substantially aligned with the vaginal orifice of the wearer, the liquid collection section has an external surface away from the wearer's body when the article is in use by the user, the The external surface is substantially free of adhesive and wherein said liquid collection section has a preferred longitudinally extending fold area, such that when the article is used by the user, at least a portion of said collection section of liquid is capable of bending in said preferred fold area in such a way that it enters the gluteal groove of the user.

2. A sanitary napkin according to claim 1, further characterized in that said liquid absorption section and said liquid collection section have an average absorption capacity, the average absorption capacity of said liquid collection section being lower to the average absorption capacity of said liquid absorption section.

3. A sanitary napkin according to claim 2, further characterized in that the average absorption capacity of said liquid absorption section and said liquid collection section have a ratio of approximately 2: 1.

4. - A sanitary napkin according to claim 2, further characterized in that the average absorption capacity of said liquid absorption section and said liquid collection section have a ratio ranging from about 2: 1 to about 3: 1.

5. A sanitary napkin according to claim 2, further characterized in that the average absorption capacity of said liquid absorption section and said liquid collection section have a ratio ranging from approximately 2: 1 to approximately 5: 1. .

6. A sanitary napkin according to claim 1, further characterized in that said liquid collection section includes a liquid impermeable layer.

7. A sanitary absorbent article according to claim 6, further characterized in that the liquid impermeable layer of said liquid collection section is continuous with the barrier layer of said liquid absorption section.

8. A sanitary napkin according to claim 7, further characterized in that said liquid collection section includes a continuous liquid permeable layer with the cover layer of said liquid absorption section.

9. A sanitary napkin according to claim 8, further characterized in that said liquid collection section is substantially free of absorbent material between the liquid permeable layer and the liquid impermeable layer.

10. - A sanitary napkin according to claim 8, further characterized in that said liquid collection section includes absorbent material between the liquid permeable layer and the liquid impervious layer.

11. A sanitary napkin according to claim 10, further characterized in that the absorbent material is continuous with the absorbent layer of said liquid absorption section.

12. A sanitary napkin according to claim 10, further characterized in that said liquid absorption section further comprises a transfer layer and the absorbent material of said liquid collection section is continuous with the transfer layer.

13. A sanitary napkin comprising: a) a liquid absorption section for absorbing the exudate material from the body, said liquid absorption section having: (i) two opposite longitudinal sides; (I) a first transverse side defining a front portion of said liquid absorption section; (iii) a second transverse side opposite the first transverse side, the second transverse side defines a posterior portion of said liquid absorption section; (iv) an imaginary longitudinal central line and (v) an imaginary transverse central line; said liquid absorption section comprises: (i) a liquid permeable cover layer, the cover layer having an external surface facing the body of a wearer when the towel is in use by the wearer; (ii) a liquid impervious barrier layer, the barrier layer has an external surface that faces away from the wearer's body when the towel is in use by the wearer; (iii) an intermediate absorbent to the cover layer and the barrier layer; (V) Adhesive material on the external surface of the barrier layer, the adhesive material being able to releasably adhere the liquid absorption section to an intimate garment of the wearer when the towel is in use; (C) a liquid collection section attached to said liquid absorption section, said liquid collection section projecting back from the second transverse side of said liquid absorption section at a distance sufficient to cover at least one groove gluteus of the user when the liquid absorption section is substantially aligned with the vaginal orifice of the user, the liquid collection section has an external surface that gives away from the user's body when the article is in use by the user, the external surface is substantially free of adhesive wherein the liquid absorption section and said liquid collection section each have an average gauge, the average gauge of said liquid capture section being less than the average gauge of said absorption section of liquid.

14. A sanitary napkin according to claim 13, further comprising: a pair of wings, a wing projecting laterally from each longitudinal side of said liquid absorption section, the wings being able to be bent over an edge a portion crotch of an intimate garment of the wearer, when the towel is in use by the wearer.

15. A sanitary napkin according to claim 14, further characterized in that the wings are continuous with the cover layer and the barrier layer of said absorption section.

16. A sanitary napkin according to claim 13, further characterized in that the average gauge of said liquid absorption section and said liquid collection section has a ratio of approximately 2: 1.

17. A sanitary napkin according to claim 13, further characterized in that the average gauge of said liquid absorption section and said liquid collection section has a ratio of approximately 2: 1 to approximately 3: 1.

18. A sanitary napkin according to claim 13, further characterized in that the average gauge of said liquid absorption section and said liquid collection section has a ratio of approximately 2: 1 to approximately 5: 1.

19. A sanitary napkin comprising: a) a liquid absorption section for absorbing the exudate material from the body, said liquid absorption section having: (i) two opposite longitudinal sides; (ii) a first transverse side defining a front portion of said liquid absorption section; (iii) a second transverse side opposite the first transverse side, the second transverse side defines a posterior portion of said liquid absorption section; (iv) an imaginary longitudinal central line and (v) an imaginary transverse centerline; said liquid absorption section comprises: (i) a liquid permeable cover layer, the cover layer having an external surface facing the body of a wearer when the towel is in use by the wearer; (ii) a liquid impervious barrier layer, the barrier layer has an external surface that faces away from the wearer's body when the towel is in use by the wearer; (ii) an absorbent layer intermediate the cover layer and the barrier layer; (iv) adhesive material on the external surface of the barrier layer, the adhesive material being able to releasably adhere the liquid absorption section to an intimate garment of the wearer when the towel is in use; (D) a liquid collection section attached to said liquid absorption section, said liquid collection section projecting back from the second transverse side of said liquid absorption section at a distance sufficient to cover at least one groove gluteus of the user when the liquid absorption section is substantially aligned with the vaginal orifice of the wearer, the liquid collection section has an external surface that gives away from the wearer's body when the article is in use by the user, The external surface is substantially free of adhesive and wherein said liquid absorption section and said liquid collection section each have a flexibility, the flexibility of said liquid collection section being greater than the flexibility of said liquid absorption section. liquid.

20. - A sanitary napkin according to claim 19, further characterized in that the flexibility of said liquid absorption section and the flexibility of said liquid collection section have a ratio of approximately 1: 2.

21. A sanitary napkin according to claim 19, further characterized in that the flexibility of said liquid absorption section and the flexibility of said liquid collection section have a ratio of about 1: 2 to about 1: 3.

22. A sanitary napkin according to claim 19, further characterized in that the flexibility of said liquid absorption section and the flexibility of said liquid collection section have a ratio of about 1: 2 to about 1: 5. SUMMARY OF THE INVENTION The present invention relates to a sanitary napkin having a liquid absorption section with two opposite longitudinal sides; a first transverse side defines a front portion of the liquid absorption section and a second transverse side is opposite the first transverse side and defines a rear portion of the liquid absorption section; the liquid absorption section includes a liquid permeable cover layer, a liquid impermeable barrier layer and an intermediate absorbent layer to the cover layer and the barrier layer; the towel further includes a liquid collection section attached to the liquid absorption section, the liquid collection section projecting back from the second transverse side of the liquid absorption section at a distance sufficient to cover less partially a gluteal groove of the wearer when the liquid absorption section is substantially aligned with the wearer's vaginal orifice; the liquid collection section has an external surface that faces away from the wearer's body when the article is being used by the user, the outer surface being substantially free of adhesive; the liquid collection section has a preferred fold area extending longitudinally such that when the article is used by the wearer, at least a portion of the liquid collection section is able to bend in the fold area preferably in such a way that it enters or adapts to the gluteal groove of the user. PG / aom * jt * ab * ald * mv * amm * P99 / 1481