MXPA99004330A - Absorbent article providing a dynamic fit - Google Patents

Abstract

An absorbent article includes a garment having opposite waist regions separated by a crotch region. At least one of the waist regions includes an expansion panel adapted to elongate in a direction substantially perpendicular to the longitudinal axis of the garment. The absorbent article also includes a pair of elastomeric strap members that are adapted to attach to the waist regions.

Description

ABSORBENT ARTICLE THAT PROVIDES A DYNAMIC ENTALLE Background of the Invention The present invention relates to garments and suspension systems. More particularly, the invention relates to an absorbent article that includes an absorbent garment and a multiple component attachment and suspension system for the garment.

Undergarments for adult incontinence are generally characterized by the use of a pair of elastic straps in combination with a generally rectangular garment.

From the incorporation of the stretchable elastic members in general, these garments are commonly formed of non-stretchable materials. The elastic strips are releasably attached to the front and back portions of the garment and are stretched in use in an attempt to hold the garment above and around the wearer and in a proper position to receive and contain the urine. A disadvantage of these incorporations is that these movements of the user can significantly impact the position and comfort of the garment. The garment can assume the position and comfort of the garment. The garment can assume a position that is not advantageous for receiving the liquid and separations or cracks can still be created adjacent to the user.

Therefore, what is missing and is required in the art is an improved garment and a system of suspension and union d strip that improves the fit of the garment and user comfort.

Synthesis of the Invention In response to the deficiencies discussed in the prior art, a new absorbent article has been developed. In an embodiment, an absorbent article includes a garment having a longitudinal axis, a first waist region, a second waist region and an intermediate crotch region interconnecting the first and second waist regions. The first waist region is adapted to stretch in a direction essentially perpendicular to the longitudinal axis. The absorbent article also includes a pair of separate elastomeric pull members, each having opposite ends adapted to join the waist regions.

In this embodiment, the first waist region is adapted to elongate in the transverse direction to the absorbent article. During use, the tir members have to function in conjunction with the first belt region to keep the garment up and around the wearer if bulging. In particular, the strip members tend to pull up and out over the waist regions of the garment. The external or transverse component of this force tends to elongate the first waist region essentially in a manner perpendicular to the longitudinal axis of the garment.

A beneficial result is that the elastomeric properties of the strip article causes the first waist region to elongate to an even larger surface area. The amount of transverse elongation increases from a relatively small amount adjacent the crotch region to a maximum near the longitudinal end edge of the first waist region. Consequently, a greater part of the lower abdomen or the user's buttocks is therefore covered by the first waist region. The first stretchable belt region may be positioned towards either the front or the rear part of the wearer, or alternatively, both the first and second waist regions may be adapted to elongate in the transverse direction of the absorbent article.

The first waist region suitably comprises a stretchable material. In a particular embodiment for example, the first waist region may comprise material which is adapted to elongate at a maximum extension without tending to retract into its unstretched state. In other embodiments, however, the first belt region comprises an elastomeric material to facilitate proper placement of the garment. The continuation of the elastomeric pull members of the first elastomeric waist region working in series causes the absorbent part of the elastomer to suffer less movement or change during use. Also, the combination of elastomeric strip members and the first elastomeric waist region provides improved comfort for distributing the elastic forces around a greater part of the user's circumference.

An absorbent article according to another embodiment includes a garment having a longitudinal axis, a waist region garment, a second waist region, and a crotch region in the middle and interconnecting the first and second waist regions. The garment includes an expansion panel disposed in both the first and second waist regions and adapted to extend in a direction essentially perpendicular to the longitudinal axis. An absorbent structure of the garment is placed on the expander panel in the crotch region. A pair of separate elastomeric pull members and each have opposite ends which are adapted to join the waist regions.

This incorporation allows a transverse extensibility in both waist regions through the use of a single expansion panel extending essentially at the full length of the absorbent article. To contain the moisture in the storage assembly, the expansion panel may comprise a liquid impervious material, or the absorbent article may comprise a barrier to the liquid impermeable wet for the expansion panel. The crotch region of the garment may, in an embodiment, be coated with a non-elastic polymer so that this part of the garment does not stretch. Alternatively, the absorbent article may comprise non-stretchable zones between the crotch region and the waist regions to isolate the extension and / or the elastic properties of each region.

Numerous features and advantages of the present invention will appear from the following description. In the description, reference is made to the accompanying drawings, which illustrate the preferred embodiments of the invention. Such incorporations do not represent the full scope of the invention. Reference should now be made to the claims herein to interpret the full scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 representatively shows a front view of an absorbent article according to an embodiment of the present invention in a condition of typical use.

Figure 2 representatively shows a plan view of a garment of the absorbent article shown in Figure 1 taken from the underside of the absorbent article in a condition stretched longitudinally and placed flat and with cut portions for purposes of illustration.

Figure 3 representatively shows an enlarged sectional view taken generally from the plane of line 3-3 of Figure 2.

Figure 4 representatively shows a part of the absorbent article of Figure 1 illustrating various dimensions and the forces acting on the suspension system during use.

Figure 5 representatively shows a plan view of a garment representing an alternate embodiment of the present invention, taken from the underside of the garment in a longitudinally stretched condition and placed flat and with cut portions for purposes of illustration.

Figure 6 representatively shows a vist in section taken generally from the plane of line 6-6 of Figure 5.

Figure 7 representatively shows a sectional view similar to Figure 6 but illustrating another alternate embodiment of the present invention.

Figure 8 representatively shows a side view of a tension tester used to measure the decay of the tension of a test specimen.

Fig. 9 representatively shows an enlarged partial front view of the tension tester and the test specimen shown in Fig. 8.

Fig. 10 representatively shows a test structure for measuring a liquid transmission rate of a material.

Detailed Description of Preferred Additions With reference to Figs. 1 and 2, it is showing an absorbent article formed according to the invention for purposes of illustration as a disposable undergarment 20 for adult incontinence, which is held in position around a user by a pair of strip members 22. As used herein, the term "disposable" includes being discarded after use and not intended to be washed and reused. . The absorbent article is illustrated in a position representing Figure 1, and Figure 20 illustrated alone in a flat placed condition with the leg elastics stretched outwardly in Figure 2. The invention may also be incorporated in other types of garments, such as other disposable absorbent articles, for example diapers, reusable absorbent articles, other personal care products or health care garments or the like.

The illustrated undergarment 20 defines a longitudinal axis or a central line represented by the arrow 24 and a transverse axis or central line represented by the arrow 25 (Figure 2). The undergarment 20 has a first longitudinal or front end edge 26, a second longitudinal end edge or rear opposite 27, and the first and second longitudinal side edges, 28 and 29 that extend between the longitudinal end edges. The undergarment 20 includes a first waist or front region 30, a second waist or back region 32 and an intermediate crotch region 34 positioned between and interconnecting the front and back waist regions. The outer edges of the undergarment 20 define a periphery 36 in which the longitudinally extending side margins are designated with the number 38 and the laterally extending end margins are designated with the number 39. The end edges 26 and 27 and the side edges 28 and 29 are desirably straight forming a rectangular shape when the garment 20 is laid flat and longitudinally stretched, but optionally may be curvilinear and contoured.

The waist regions 30 and 32 of the interior trim 20 comprise the first second expansion panels, 40 and 42. As explained in more detail below, the expansion panels 40 and 42 are adapted to lengthen during use in a direction that it is essentially perpendicular to the longitudinal axis 24 of the undergarment 20. By extending essentially perpendicular to the longitudinal ej 24, the expansion panels provide a hedging over the abdomen and buttocks of the wearer. In particular embodiments, the expansion panels 40 and 4 comprise the elastomeric materials that function in combination with the elastomeric strip members 22 so that the liquid storage portion of the garment 20 undergoes less movement during use. The comfort is also better because the elastic forces of the undergarment 20 are distributed around a larger part of the user's circumference. Correspondingly, the undergarment 20 e better conforms to the wearer's body so that less separation is formed between the undergarment and the body.

The comparison of the shape of the inner garment 20 in figures 1 and 2 illustrates an important characteristic of the invention. In Figure 2, the garment 20 is stretched lengthwise so that the leg elastics 66 is elongated and the garment can lie flat. In this condition, the garment 20 has the generally straight end edges 26 and 27 of the side edges 28 and 29. Thus, the garment 20 has a generally uniform width over the entire length of the garment. In contrast, however, when the garment 20 is stretched longitudinally transversely such as during use, the garment has a dog bone or hourglass shape as illustrated in Figure 1. The width of the waist regions 30 and 32 is actually greater during use than in the longitudinally stretched flat condition shown in Figure 2, because the expansion panels 40 and 42 are elongated in order to balance the retraction forces provided by the strip members 22. crotch region 34 can be formed or traced to be essentially non-stretchable in transverse direction 25 so that its width remains the same before and during use, although it may look somewhat narrower in Figure 1 because it is compressed between the user's legs.

The undergarment 20 may include an expansion panel in only one waist region or an expansion panel in both waist regions 30 and 32. In the latter case, the elastomeric materials used to build the expansion panels 40 and 42 may have the same or different elastomeric properties. In the latter case, the expansion panels 40 and 42 can be constructed with different expansion and / or retraction properties to improve the notch. For example, the expansion panel designed to be exposed to the user's back may be adapted to expand to a greater extent than the other expansion panel in order to provide greater buttock coverage.

The crotch region 34 of the undergarment 20 comprises a storage assembly 44 (Figure 2) which is adapted to take and hold liquids such as urine. The storage assembly 44 is positioned between and interconnects the expansion panels 40 and 42. The terms "placed", "placed on", "placed with", "placed on", "placed close" and variations thereof, are attempts to denote that an element can be an integral part of another element or that an element can be a separate structure attached or placed with or placed near another element, the storage assembly 44 is spaced longitudinally inwardly from the end edges 26 and 27 and is separated from the end edges by the expansion panels 40 and 42.

The front waist region 30 is contiguous with the front end edge 26 and extends longitudinally inward therefrom to the transverse center line 25. The rear waist region 32 is contiguous in the rear end bord 27 and extends longitudinally. made therein to the transverse center line 25 For the purposes of the present invention, the front and rear waist regions 30 and 32 are considered to terminate in the respective attachment regions 46 and 47. These regions d junction 46 and 47 they represent locations in which the expansion panels 40 and 42 are attached to the storage assembly 44. As used herein, the term "attached" refers to the joining, adhering, holding or the like of two elements. Two elements will be considered to be joined together when they are directly linked to one another or indirectly to one another, such as when each is directly linked to an intermediate element or elements.

In the embodiment illustrated in Figures 1 and 2, therefore, the first expansion panel 40, the second expansion panel 42 of the storage assembly 44 are separate structures that are joined together in the joining regions 46 47. As was used in the present description, the term "separate" refers to two or more distinct elements rather than a single unitary element or to several parts of a single unitary element.A wide variety of joints may be suitable for joining, including ultrasonic connections, thermal joints, adhesive joints or similar.

The waist regions 30 and 32 comprise those upper portions of the undergarment 20 which, when worn, cover or completely or partially surround the lower middle waist or torso of the user. The intermediate crotch region 34 comprises the part of the undergarment 20, which, when worn, is placed between the user's legs in the perineum and covers the lower torso of the user. Thus, crotch region 34 is the area where urine discharges typically occur in the undergarment or other absorbent article.

With further reference to Figure 3, the storage assembly 44 includes a moisture barrier essentially impermeable to liquid 50, an absorbent structure 52 placed on the moisture bar and a side-to-body liner essentially permeable to liquid 54 attached to the body. the barrier to moisture to have the absorbent structure between them in the form of a sandwich. As illustrated, the moisture barrier 50 and the body side liner 54 are coterminous and larger and wider than the absorbent structure 52 so that the peripheries of the moisture barrier and the side-to-body lining can join together using ultrasonic joints, thermal bonds, adhesives, or other suitable means. The periphery of the moisture barrier 50, of the side-to-body liner 54, or the peripheries of both, desirably form the side margins 38 of the undergarment 20 and include the joined regions 46 and 47 for the union of the panele expansion 40 and 42. The absorbent structure 52 may also be attached to the moisture barrier 50 and / or the side-by-side liner 54 using ultrasonic joints, thermal bonds, adhesives, or other suitable means.

The moisture barrier 50 desirably comprises a material that is formed or treated to be impervious to liquid. Alternatively, the moisture barrier 50 may comprise a liquid permeable material and other suitable means may be provided to prevent the movement of liquid out of the absorbent structure, such as a liquid impervious layer (not shown) associated with the absorbent structure. 52. The moisture barrier 50 may also be gas permeable, this may have "ability to breathe" so that the expenses encountered during use of the absorbent garment are able to pass through the material under ordinary conditions of use. , on any or all parts of its surface area.

The moisture barrier 50 may comprise a single material layer or a laminate of two or more separate layers of material. Suitable wet barrier materials include films, fabrics, nonwovens, laminates of films, fabrics and / or similar non-wovens. For example, the moisture barrier 50 may comprise a fabric substantially permeable to the thin liquid or a sheet of plastic film such as polyethylene, polypropylene d, polyvinyl chloride or a similar material. The moisture barrier material can be transparent, it can be opaque and have a matte or etched surface. The particular material for the moisture barrier 50 is a polyethylene film having a laminar thickness of about 0.25 millimeters and a systematic matte etching pattern, and which has been corona treated on both sides. As shown in FIG. 3, the moisture barrier material illustrated comprises a thermal adhesive or laminate comprising a set or blown film 56 formed of polypropylene, polyethylene or the like, and a yarn bonded fabric 58 formed of fibers. of polypropylene and polyethylene bicomponent in a 50/50 side-by-side configuration.

The absorbent structure 52 comprises materials adapted to absorb and retain liquid waste. The absorbent structure 52 may comprise various absorbent materials such as a block formed by air of cellulosic fibers such as wood pulp fluff or co-material material composed of cellulose fiber blend and synthetic polymer fibers. The polymer fibers can be incorporated, for example, in the manner described in U.S. Pat. No. 5,227,107 issued July 13, 1993 to Dickenson et al. Absorbent structure 5 may also include compounds for increasing absorbency, such as from 0-95 percent by weight of organic or inorganic high-absorbency materials, which are typically capable of absorbing at least about 15 desirably more than 25% by weight. times its weight in water. Suitable high-absorbency materials are described in U.S. Pat. Nos. 4,699,823 issued Oct. 13, 1987 to Kellenberger et al. And 5,147,343 issued September 15, 1992 to Kellenberger, which are incorporated herein by reference. . High-absorbency materials are available from various commercial vendors such as Do Chemical Company, Hoechst Celanese Corporation and Allie Colloids, Inc.

Absorbent structure 52 may also include tissue, acquisition and / or distribution layers to help maintain the integrity of fibrous absorbers or transport liquids (not shown). The illustrated absorbent structure 52 comprises an absorbent block 60 sandwiched between two layers of tissue 62 (Figure 2). The general form of the absorbent structure 52 may correspond to the shape of the storage assembly 44 or assume a different form. In an alternate embodiment, the longitudinal ends of the absorbent structure 52 are coterminous with the longitudinal ends of the longitudinal barrier 50 and of the side-to-body lining 54.

The body side liner 54 is formed of liquid permeable material so that liquid waste, and possibly also the semi-solid can pass through the liner and be absorbed by the absorbent structure 52 Suitable side-to-body linings 54 can comprising a non-woven sheet or fabric of a moisture-resistant tissue paper, a perforated film, a fabric bonded with meltblown or bonded yarn and carded yarn composed of synthetic polymer fibers, such as polypropylene, polyethylene, polyesters or the like. A natural polymeric filament or fiber fabric such as rayon or cotton In addition, the body side liner 54 can be treated with a surfactant to aid in the transfer of liquid. In a particular embodiment of the invention, the liner 54 comprises a polypropylene fabric bonded with composite non-woven yarn d about 2.8 - 3.2 deniers formed into a woven fabric having a basis weight of about 22 grams per square meter and a density of around 0.06 gm / cc. The fabric is treated to the surface with about 0.28 percent by weight of surfactant commercially available from Union Carbide Chemical and Plastics Company, Inc. of Danbury, Connecticut, United States of America under the trade designation Triton X-102.

The term "cloth" is used herein to refer to all fibrous, knitted and non-woven fabrics. The term "non-woven tel" means a fabric of material which has been formed without the aid of a weaving or knitting process. Non-woven fabrics have been formed from many processes, such as, for example, meltblowing processes, spinning processes, the coform formation process and the carded and bonded tissue processes. The basis weight of the non-woven fabrics is usually expressed in ounces of material per square yard (osy) or in grams per square meter (gsm) and useful fiber diameters are usually expressed in microns.

Desirably, even if not necessarily, the storage assembly 44 also includes the leg elastic members 66 (FIG. 2) for pulling and holding the lateral margins of the undergarment 20 against the wearer's legs and forming a seal therewith. . The elongated leg elastic members 66 are oriented longitudinally on each lateral margin, extending toward the front and rear end edges 26 and 27. The elastic leg members 66 are positioned in the embodiment illustrated between the moisture barrier 50 and the lining. from side to body 54. Using the ultrasonic bonds, the adhesives, the thermal bonds, or other suitable means, the elastic leg members 66 are attached in a stretched condition to the moisture barrier 50, to the side-to-body liner 54 , or both, in either a straight or an arched shape. Alternatively, the leg elastic members 66 may be attached in a relaxed state to a part taken from the moisture barrier 50, lining side to body 54 or both.

The elastic leg members 66 can be formed from a dry-spun multi-filament elastomeric elastomer yarn sold under the trade name of Comerci LYCRA® and available from EI du Pont de Nemours and Company Alternatively, the elastic members can be formed from other typical elastics used in the art of manufacturing interior garments, such as a thin natural rubber tape, wet spun spandex materials, a rolled and stretched laminate material comprising a blown inner layer with pre-stretched elastic d melt placed in sandwich form between joined to a pair of non-woven polypropylene fabrics bonded together or the like. Other suitable elastic means of recollection are described in the patents of the United States of America Nos. 4,938,754 granted to Mesek and 4,388,075 granted to Mesek.

The expansion panels 40 and 42 are adapted to allow the waist regions 30 and 32 to elongate in the transverse direction 25 during use. More specifically, the elongation of the strip members 22 when the inner garment 20 is put on provides a retraction force acting on the expansion panels 40 and 42 and is directed at an angle in relation to the longitudinal axis 24 of the undergarment. The effective width of the expansion panels 40 and 42 is made to be increased by the transverse component of this retraction force, so that the expansion panels assume an approximately trapezoidal shape. The increased body coverage allowed by the expansion panels during use provides greater comfort and a sense of security.

The expansion panels 40 and 42 are suitably formed of a stretchable material that is adapted to extend in response to an applied force. Therefore, in one embodiment, the expansion panels 40 and 42 are extensible but not fully recovered with the removal of the applied force. The suitable elongated materials have a maximum elongation, this is the property of a "stretch to the top" so that the expansion panels do not elongate to the point where the connection and suspension system can no longer maintain sufficient tension to hold the garment on the user. The terms "extension", "extends" and "extended" refers to the change in length of a material due to stretching, expressed in units of length. The term "force" includes a physical influence exerted by one body on another which produces acceleration of the bodies that are free to move and the deformation of bodies that are not free to move. The term "elongation" as used herein, refers to the change in length of a material due to elongation, this is the elongated length, less the original length, divided by the original length of the material, multiplied by 100 and expressed in percent .

More desirably, the expansion panels 42 can be formed of an elastic or elastomeric material, so that the extension and extension recovery properties of the expansion panels and the strip members 22 work in combination to improve the notch. the undergarment 20. The terms "elastic", "elasticized" and "elasticity" are used here to mean that property of a material by virtue of which, it tends to recover its original size and shape after the removal of a force which caused a deformation. The term "elastomeric" as used herein, refers to a material or compound, which may be elongated by at least 60 percent of its relaxed length and which will recover with the release of force applied by at least 55 percent of its elongation.

As used herein, the term "recover" refers to a contraction of a stretched material upon termination of a force after stretching of the material by application of force. For example, if a material having a relaxed and not extended length of one inch is lengthened by 20 percent by stretching to a length of 1.2 inches, the material will have an extended length that is 120 percent of its length not extended. If this stretched example material contracts, ie, recovers to a length of 1.1 inches after the release of the stretching force, the material will have recovered 50 percent (0. inches) of its elongation.

As previously noted, the expander panels 40 and 42 are desirably adapted to extend in a direction that is essentially perpendicular to the longitudinal axis 24 of the undergarment 20. Thus, the expander panels 40 and 42 may be formed from a material " stretched in the transverse direction "which is adapted to elongate in a direction that is perpendicular to the longitudinal axis 24. The term" essentially perpendicular "as used herein refers to material adapted to elongate in a direction that forms or angle with the axis longitudinal 24 between about 70 and 9 degrees, and more particularly between about 80 and 90 degrees and desirably about 90 degrees, such as 90 degrees Applicants currently speculate how much of elasticity significance in the longitudinal direction, for example elongations of more than about 10 percent in the longitudinal direction 24 under typical conditions of use can decrease inuir the ability of the undergarment 20 to resist bagging when fully loaded with urine.

To improve the comfort of the internal garment , the expansion panels 40 and 42 may be formed of a "breathable" material. For example, suitable expansion panels 40 and 42 have a water vapor transmission rate (WVTR) of at least about 1000 grams per square meter per 24 hours (gm / m2 / 24 hours). A suitable method for determining the water vapor transmission rate of a material is the water vapor transmission rate test set forth in the test procedure section given below.

Additionally, expansion panels 40 and 42 may beneficially have a relatively low ability to transmit liquids. In particular embodiments, expansion panels 40 and 42 have a liquid transmission rate of less than about 3 centimeters per 30 minutes. The liquid transmission test which is included in the test procedure section given below is a suitable procedure for determining the liquid transmission properties of the expansion panels 40 and 42.

Examples of materials suitable for the construction of expansion panels 40 and 42 include stretchable materials, elastic materials, or elastomeric materials such as polymer films, woven fabrics, knitted fabrics, non-woven fabrics. or similar, as well as combinations thereof. In particular aspects of the invention, the expansion panels 40 and 42 may be composed of a stretched-bonded-laminate (SBL) material, a narrow-bonded-laminate (NBL) material, or a reversibly tapered non-woven material, of an elastomeric film, and an elastomeric foam material, elastic yarns or the like. For example, melt blown elastomeric fibrous fabrics suitable for forming the expansion panels 40 and 42 are described in U.S. Patent No. 4,663,220 issued May 5, 1987 to T. Wisneski et al., Whose description it is incorporated here by reference. Examples of composite fabrics comprising at least one layer of a non-woven textile fabric secured to a fibrous elastic layer are described in European Patent Application No. 0 127 032 A2 published on April 8, 1987 with the inventors listed as J. Taylor et al., the description of which is incorporated herein by reference. Examples of narrow-bonded-laminate materials are described in U.S. Patent No. 5,226,992, issued July 13, 1993 to Morman, in 5,336,545 issued August 9, 1994 to Morman and 5,514,470 granted on May 7, 1996 to Haffner and others; whose descriptions are incorporated herein by reference.

As previously described, the expansion panels 40 and 42 may be formed of a material capable of stretching in one direction or less desirably capable of stretching in multiple directions. A suitable unidirectional stretching material is described in U.S. Patent No. 4,720,415 issued January 19, 1988 to Vander Wielen et al., Which is incorporated herein by reference. In a material stretched in the transverse direction, it may comprise a composite material that includes at least one recoverable fabric attached to at least one elongated elastic fabric. The elastic fabric can be an elastic film or fibrous nonwoven elastic fabrics such as meltblown elastomeric fibrous fabrics. In one embodiment, the expansion panels comprise a bonded and stretched laminate formed of an inner layer blown with elastic melt and pre-stretched placed in sandwich form between and attached to a pair of non-woven polypropylene fabrics bonded with yarn having a base weight of about 13.6 grams per square meter (0.4 oz / yd2). Suitable elastic materials can be purchased from the Shell Chemical Company of Houston, Texas, under the trademark KRATON. Other suitable unidirectional stretching materials are described in U.S. Patent Nos. 4,965,112 issued October 23, 1990 to Morman; 4,606,964 granted on August 19, 1986 to Widerman and 4,657,802 granted to Morman on April 14, 1987.

The two-way stretch materials that can be used for the expansion panels 40 and 42 are described in the United States of America patents Nos. ,114,781 granted on May 19, 1992 and 5, 116,662 granted on May 26, 1992 to Morman, which are incorporated herein by reference. A two-way stretch material can comprise a composite material that includes a narrowable material and an elastic sheet, which can be formed by extrusion or meltblowing. Narrow materials are those which can be constricted in at least one dimension by applying a tensioning force in a direction perpendicular to the desired direction of downward constriction, and may include a spunbond, meltblown or bonded fabric and carded. The stressed narrowable material can be attached to the stretched elastic sheet at spaced or arranged locations in a non-linear configuration. Another composite material stretched in two directions may comprise one or more layers of a narrowed material reversibly bonded to one or more layers of an elastic sheet at spaced locations. Reversibly narrowed materials are those that have been treated, such as with heat, while being tapered to impart memory to the material so that, when a force is applied to extend the material to its pre-narrowed dimensions, the portions shortened and treated they will generally recover to their narrowed dimensions with the termination of the force.

The term "attached and stretched" refers to an elastic member that is attached to another member while the elastic member is extended by at least about 25 percent of its relaxed length. The term "bonded and stretched laminate" refers to a composite material having at least two layers in which one layer is a foldable layer and the other layer is an elastic layer. The layers are joined together when the elastic layer is in an extended condition so that with the loosening of the layers, the recoverable layer is collected. Such elastic multi-layer composite material can be stretched to the extent that the non-elastic material collected between the bonding sites allows the elastic material to elongate. One type of bonded and stretched laminate is described, for example, in U.S. Patent No. 4,720,415 issued to Vander Wielen et al., In which multiple layers of the same polymer produced from multiple banks of extruders are used. Other composite elastic materials are described in U.S. Patent Nos. 4,789,699 issued to Kieffer et al., 4,781,966 issued to Taylor; 4,657,802 and 4,652,487 granted to Morman; and 4,655,760 granted to Morman and others. As used herein, the term "composite elastic material" refers to an elastic material which may be a multi-component material or a multi-layer material in which a layer is elastic.

The expansion panels 40 and 42 may include the reinforced segments 70 that are coterminous with the end edges 26 and 27 and extend to the full width of the undergarment 20 (Figure 2). In the illustrated embodiment, the reinforced sections 70 comprise the bent regions 71 wherein the expansion panel material is bent over generally folded in thickness. The thick bent regions 71 are maintained by suitable joints 72, such as ultrasonic joints, thermal bonds, adhesive bonds, mechanical joints and the like. Alternatively, the reinforcing segments 70 may be formed into a separate layer of material that is bonded to the expansion panels 40 and 42 to form the regions that are generally folded in thickness (n shown). Such a separate material will desirably be formed of an extendable or an elastic material having similar properties, but not necessarily identical to those of the expansion panels 40 and 42.

For joining the strip members 22 (Figure 1), the expansion panels 40 and 42 of the illustrated embodiment define slits 74 (Figure 2) formed near the corners of the undergarment 20. The integrity of the slits 74 can Improved by backing patches 76 which are attached to expansion panels 40 and 42 using adhesives, ultrasonic bonds, thermal bonds, mechanical joints, or the like.

The reinforcing segments 70 can function to improve the elastic properties of the expansion panels 40 and 42 along the end edges 26 and 27. In particular, the reinforcing segments 70 provide recovery forces greater than a given elongation, in comparison to the reinforced n portions of the expansion panels 40 and 42. Provided that the slits 74 or other forms of strip attaching fasteners are disposed in the reinforcing segments 70, this beneficially reduces the separation of the undergarment 20 in the waist regions 30 and 32.

The joining regions 46 and 47, which secure the expansion panels 40 and 42 to the storage assembly 44, can have a shape of (square) which is a form of - [and a shape of] respectively when viewed in the top plan view, such as in Figure 2. At each end the shape of the square bracket is directed to open in the direction of the absorbent structure 52. More precisely, the joined regions 46 and 47 have a longitudinal dimension which is greater on or on one side of the side margins 38 than on the transverse center of the undergarment 20. As a result of this, the inner edges of the expansion panels 40 and 42 form the non-adhered end flaps 80. Alternately , the joined regions 46 and 47 can have a constant longitudinal dimension across the width of the undergarment 20 or they can be arched (not shown).

As best seen in FIG. 3, the end flaps 80 represent portions of the expansion panels 40 and 42 which are positioned longitudinally inward of the attachment regions 46 and 47 and which are at least partially not adhered to the assembly. storage 44. As used herein, the term "non-adhered" refers to an absence of sufficient strength bonds to withstand the forces typically encountered during ordinary use of the undergarment. S speculates that the end flaps 80 impair the movement of the liquid toward the waist regions 30 and 32, and are particularly useful when the expansion panels 40 and 4 comprise liquid permeable materials. The end flaps 80 may also be formed or treated to be liquid impervious. It is speculated that the increased longitudinal dimension of the joined regions 46 and 47 on or adjacent to the side margins 38 is useful for supporting the elongation force of the expansion panels 40 and 42.

The strip members 22 illustrated in the figure are separate structures of the undergarment 20 and each one comprises the attachment components for releasably fastening the strip members to the rear front waist regions 30 and 32. The fastening components include a retainer 84 in the form of a button attached at each end d each strip member 22 (figure 1, only one half of each strip s sample). The detents 84 can be releasably secured in the slots 74 and the expansion panels 40 and 42. When the undergarment 20 is placed over the wearer, the strip members 22 extend between the front and back slits 74 so that the detents 84 can be released freely in the slits. Optionally, other types of retaining devices such as hooks, curls, bulbs, mushrooms, arrowheads, balls on rods, or the like can be employed. The illustrated joining system as well as the alternatives thereof are described in United States of America Patent No. 4,315,508 granted on February 16, 1982 to Bolick and in United States of America Patent No. 5,386,595 issued on February 7, 1982. February 1995 to Kuen and others whose descriptions of which are incorporated herein by reference.

Strip members 22 (Fig. 1) are generally rectangular strips of material, which material is desirably an elastic material capable of stretching more than twice its relaxed length, for example to about 2.8 to 5 times its relaxed length. The strip members 22 desirably have a length of from about 5 to about 41 centimeters (cm) and a width of from about 1 to about 10 centimeters. Each strip member 22 can be 28 centimeters long and 2.5 centimeters wide. The cut ends of the strip members 80 may be joined by ultrasonic, adhesive or other suitable means to prevent shredding.

Materials suitable for use on strip members 22 include a woven / polyester interwoven fabric with a nylon liner backing available from Shelby Elastics, Inc. of Shelby, North Carolina, United States of America, under the trade designation. K-78. Another suitable material is a 1.5 inch (3.81 cm wide) elastomeric strip comprising a 50 caliber neoprene elastomer at 23 end per band of JPS Elastomerics of Greensboro, North Carolina, United States of America; 4 threads of number 70 of white nylon thread, and monofilaments of number 4 and number 8; the strip generating a tension of around 550 grams at an elongation of 100% and a tension decay of 15.4 percent after one hour at an elongation of 100%. Another suitable strip material available from Shelby Elastics, under the trade designation NP-50, comprises 50-gauge neoprene elastomers generating a tension of about 510 grams at an elongation of 100 percent and a strength decay of 14.7 percent after from one hour to a lengthening of 100 percent.

In use, the undergarment 20 is placed on the wearer and secured with the restraint system. The strip members 22 are elongated as necessary so that the buttons 84 can be releasably secured in the slits 74 of the undergarment 20. Due to the elasticity and / or elastic properties of both the strip members 22 and expansion panels 40 and 42, each of these components is considered for the purposes of the present invention as forming part of the multi-component suspension and joining system that holds the garment loosely on the wearer during use. The selection of materials for the suspension and joining system is important for proper operation of the absorbent article. It is desired that the absorbent article should not be depleted during use, even if the storage assembly 44 contains a large amount of liquid. In addition, it is desirable that the absorbent article minimizes the separations of the garment 20, which could otherwise create trajectories for the liquid to escape from the garment.

Initially, it is desirable that the expansion panels 40 and 42 extend in the transverse direction. (figure 2) when the garment is applied. This provides greater psychological security due to the expansion panels 40 and 42 cover larger portions of the user's buttocks and / or abdomen. Furthermore, in the incorporations and where the expansion panels comprise an elastic material, the garment is more comfortable, because the elastic forces extend around the full circumference of the wearer. Also, by constructing the undergarment 20 so that the elasticity of the expansion panels 40 and 42 is essentially complete in the transverse direction decreases the possibility of the garment collapsing when the warehouse assembly 44 is loaded.

Furthermore, the increased size of the expansion panels 40 provides more surface area in contact with the user than a conventional undergarment, and consequently, because the amount of friction increases in the contact area, the garment 20 must withstand more load before slipping than a conventional undergarment.

In addition to lengthening the expansion panels 40 and 42 in the transverse direction 25, the interior trim 20 tends to make more type of undergarment and / or d type of underpants. This allows the strip members 22 to be made shorter than with the n-expandable waist regions. The complete garment 20 will then provide the user with additional sensations of normality and psychological comfort. In addition, the extension of the strip members 22 is now complemented by the extensibility of the expansion panels 40 and 42 so that the absorbent article fits a larger range of user sizes. If the expansion panels 40 and 42 are formed of breathable materials, the waist regions 30 and 32 make the added benefit of allowing moisture to evaporate or migrate from the surface of the skin, thereby keeping the user cold and dry. .

Expansion panels 40 and 42 desirably remain in an extended condition during use to continue to provide increased body coverage.

If, conversely, the expansion panels 40 and 42 were excessively retracted during use and the strip members 22 were to be lengthened, the notch, comfort and psychological safety benefits associated with the increased body coverage would be lost. In addition, the notch close to the body will damage it and the separation of the product will increase, which could lead to the discharge of urine out of the product.

The operation of the undergarment 20 and the strip members 22 will now be described in greater detail in relation to Figure 4, which representatively shows the forces acting on the suspension system and uniÁ during use. The strip members 22 are elongated during use and are generally positioned at an angle relative to the longitudinal axis 24, such as from about 25 to 90 degrees. The properties of each strip member 22 generate a force vector Vs for each strip member, which comprises a horizontal VSH component and a vertical Vsv component. Each corner of the first expansion panel 40 experiments an opposing and generally equal force vector VP which comprises a horizontal component VPH and a vertical component VPV. The first expansion panel 40 will elongate in a direction generally perpendicular to the longitudinal axis 24 of the undergarment 20 to the point where the VSH horizontal force components of the 4"" >.; - • __! . and. 1 nar.ß l HP vnan? Balanced p ost n Significantly, the expansion panel 4 desirably has sufficient elongation resistance in the longitudinal direction 24, so that the expansion panel n is significantly elongated in the longitudinal direction and response to the vertical force component Vsv of the pull member 22, minimizing by both the bagging of the undergarment In order to obtain an increased body coverage, it is desirable that the first second expansion panels 40 and 42 be adapted to have an extended width during use (FIG. 4) that is substantially greater than the non-extended width Wa (FIG. 2) . Specifically, the extended width WE is desirably at least about 11 percent, more particularly at least about 125 percent, and even more particularly at least about 135 percent of the non-extended width W0 . The extended width u and the undefined width Wy of the expansion panels 40 and 42 are both measured between the longitudinal edges 28 and 29 of the garment 20 in the longitudinal location corresponding to the points of attachment of the strip members 2 to the shoulders. expansion panels 40 and 42. The non-extended width W0 e measured when the undergarment 20 is laid flat without a transverse force applied to the expansion panels (figur 2), while the extended width WE is measured during the use or conditions of simulated use.

With further reference to Figure 4, it will be evident that the amount of transverse extension of the first and second expansion panels 40 and 42 is greater near the end edges 26 and 27 of the undergarment 20. L transverse extension of the first The waist panel 40 is shown at four longitudinally spaced locations designated e2, e3 and e4, starting at one side of the crotch region 34 (ey spaced evenly, with respect to the longitudinal location corresponding to the attachment points d the members of strip 22 to the expansion panels 40 and 42 (e4) By definition, the amount of transverse extension e4 in the longitudinal place corresponding to the attachment points of the fasteners is the same as W £. and 42 have generally uniform elongation properties, the amount of transverse extension in the longitudinally spaced locations will result in: e4> e3> e2> e1.

Expansion panels 40 and 42 must have a length dimension L (Fig. 2) sufficient to provide the desired degree of body coverage. In particular, the expansion panels 40 and 42 suitably have a length dimension of L of at least 5 centimeters (cm), more particularly of about 10 centimeters, such as from about 12.5 to about 20 centimeters to u improved operation. The dimension of adequate length L d lo =. nati lfif. of expansion 40 v 42 may also be characterized in relation to the width dimension Ws of strip members 22 (Figure 4). It is desirable, for example, that the length dimension L of the expansion panels 40 and 42 be at least 200 percent of the width dimension Ws of the strip members 22, more particularly of at least 250. percent, and even more particularly of at least about 300 percent for improved performance.

The length dimension L (Fig. 2) is a measure of those portions of the waist regions 30 and 32 that extend transversely without breaking when the garment is worn, measured parallel to the longitudinal axis 24. In the illustrated embodiment, the dimension of length L of each expansion panel 40 and 42 extends from the respective joining region 46 and 47 to the respective end edge 26 and 27. The portions of the expansion panels 40 and 42 forming the end flaps 80 are not included in the dimension of length L because they do not lengthen transversely when the garment is worn.

The strip members 22 are desirably adapted to retract over time to accommodate the stress decay of the expansion panels 40 and 42. Thus, the expansion panels 40 and 42 desirably have voltage decay values greater than that of the strip members 22. For the purposes of the present invention, the term "tension decay" refers to the property of elastic material to lose its recovery force over time. The strip members 22 must have a resistance to stress decay than the expansion panels 40 and 42 so that the strip members can be retracted to take any loosening by lengthening the expansion panels while the product is being used. Yes, on the other hand, the strip members 22 have higher voltage decay values than the expansion panels 40 and 42, the panels will tend to retract to take the loosening in the system and thus decrease the coverage of the buttocks and / or of the frontal waist region. A suitable method for determining the decay of the tension of an expansion panel or of a strip member is the tensile stress test at 100 percent elongation established hereinafter. Suitable strip members desirably have a tensile stress decay value of less than about 20 percent after one hour at an elongation of 100 percent, meaning that they lose 20 percent of their original retraction force.

The suspension system must provide sufficient force against the wearer's body to keep the undergarment 20 in place during use. Accordingly, it is important that at least one of the components of the suspension system, ie the strip members 20, the expansion panels 40 and 42 or both, develop maintain sufficient retraction forces so that the garment 20 does not fall out in use. For example, if the expansion panel material will be extended continuously during use until the strip retracts, to a point where the force is too low, the garment 20 would fall out. Conversely, if the strength of the strip decays and / or is continuously lengthened, the garment 20 will again become very loose. Therefore, the elastic properties of the strip and of the suspension system and of the panel fastening in series must maintain sufficient retraction force over time to keep the garment in place on the user when being loaded with urine.

A. alternate incorporation of the invention is illustrated in Figures 5 and 6 by an undergarment 100 qu is adapted for use with the separate strip members 22.

Components similar to those previously described have given the same reference number. The undergarment 100 has a dimension of longitudinal length measured between the opposite end edges 26 and 27 parallel to the longitudinal axis 24. The undergarment 100 comprises a single expansion panel 102 having a length essentially equal to the total longitudinal extension dimension d of the undergarment. The expansion panel 102 is a single unitary element and is therefore placed in the front and rear waist regions 30 and 32 v in the crotch region 34. In the illustrated embodiment, the expansion panel 102 forms the opposite end edges 2 and 21 and therefore defines the dimension of longitudinal extension. The expansion panel 102 may also include the bent regions 71 and have the backing patches 76 attached thereto. The expansion panel 102 is adapted to extend in an essentially perpendicular direction to the longitudinal axis 24. A storage assembly 44 is placed on the expansion panel 102 between the opposite end edges 26 and 27. L longitudinal extension of the storage assembly 44 it is less than the longitudinal extension dimension of the inner garment 100. For the purposes of the present invention, the front and rear waist regions 30 and 32 are defined as those portions of the undergarment 100 that are positioned longitudinally beyond the garments. ends of the storage assembly 44. Thus, the storage assembly 44 is positioned in the crotch region 44. The storage assembly 44 in the embodiment illustrated comprises a moisture barrier 50, an absorbent structure 52, and a liner 44. side to body 54 and can be attached to the expansion panel 102 using the adhesives, the ultrasonic joints nicas, thermal joints or other suitable means. Alternatively, the expansion panel 102 may comprise a liquid impervious material and a storage assembly 44 may exclude a separate moisture barrier 50 (not shown). The illustrated absorbent structure 52 includes an absorbent block 60 placed in the form of a sandwich between two layers of tissue 62. The storage assembly 44 may also include the leg elastic members 66 at the lateral margins.

In the front and rear waist regions 30 and 32, the expansion panel 102 is unhindered by the storage assembly 44 and is therefore capable of elongation essentially perpendicular to the longitudinal axis 24 to provide greater coverage over the abdomen and the user's buttocks. The waist regions 30 and 32, and specifically the portions of the expansion panel 102 that extend longitudinally beyond the storage assembly 44 and are transversely elongated when the garment 100 is worn., desirably has a length dimension L (Fig. 5) of at least 5 centimeters, more particularly of at least 10 centimeters, such as from about 12.5 to about 20 centimeters for improved performance. The length dimension L is desirably at least 200 percent of the width dimension Ws of the strip members 22, more particularly of at least 250 percent, and even more particularly of at least about 300 percent for improved performance. The crotch region 34 generally will not elongate in the transverse direction 25 because it is restricted by the storage assembly 44.

The expansion panel 102 can be formed of the same materials as described in relation to panels 40 and 42 of the embodiment of Figure 1 and desirably comprises an elastomeric material. The full-length expansion panel 102 illustrated in Figures 5 and 6 can alternatively form one of the layers of the side-to-body liner 54 or moisture barrier 50 (not shown). Still alternatively, the full-length expansion panel may comprise multiple layers including the layers that form the side-to-body liner 54, the moisture barrier 50, or both.

For example, a further alternate embodiment of the invention is illustrated in the sectional view in Figure 7 by an undergarment 120 that is adapted for use with the separate strip members 22 (not shown) the undergarment 120 comprises a pair of undergarments. expansion panels 122 and 124 extending between the opposite end edges 26 and 27 of the undergarment. Both expansion panels 122 and 124 are positioned in the front and rear waist regions 30 and 32 and in the crotch region 34. Also, both expansion panels 122 and 124 are adapted to elongate in a direction essentially perpendicular to the longitudinal axis of the body. undergarment 120. Strip members 22 may include buttons for joining button holes 74 (not shown) reinforced with backing patches 76.

An absorbent structure 52 is positioned between the expansion panels 122 and 124 in the crotch region 34. The crotch region 34 may also include the leg elastic members 66 (not shown).

For both reasons of performance and product appearance, it may be desirable to isolate the elasticity of the crotch region 34 from the stretchability and / or elasticity of the waist regions 30 and 32. In particular, it is believed that it is desirable to isolate waist regions 30 and 32 of the longitudinal elasticity provided by the elastic leg members 66, thereby minimizing the opportunity for the elastic leg members to contribute to pulling the garment down the hip and the waist regions of the wearer .

In the crotch region 34 and the waist regions 30 and 32 may be elastically isolated from one another by providing essentially non-stretchable zones placed between the crotch and waist regions. For example, the non-stretchable zones as indicated in reference numeral 126 may be provided by essentially decreasing or killing the extension and / or elastic properties of the expansion panels 122 and 124 by means of the ultrasonic joints, the adhesive bonds. , thermal joints or similar. The non-stretchable zones 126 are suitably positioned near the longitudinal ends of the absorbent structure 52 and extend through essentially the full width of the undergarment.

The expansion panels 122 and 124 in the embodiment of Figure 7 function as the side-to-side liner and the moisture barrier having the absorbent structure 52 in the form of a sandwich therebetween. Suitable materials for forming the expansion panels 122 and 124 are described in relation to the expansion panels 40 and 42 of the embodiment of Figure 1 and desirably comprise the stretchable and / or elastomeric materials. The materials can be formed or treated to possess the desired degree of liquid permeability.

Examples Having thus described the present invention and the process for making it, a series of examples were prepared to give a more detailed understanding of the invention. These examples and the test procedures for measuring them are set forth below. The amounts, proportions, compositions and parameters are intended to be exemplary and are not intended to specifically limit the scope of the invention.

A system voltage decay test was conducted to compare various materials in use with expansion panels in the present invention. The test d decay of system tension in some aspects makes parallel the operation of the suspension system and multi-component clamping during conditions of use. The proof, which is graphically illustrated in Figures 8 and 9, employs a Sintech material testing system, also known as a voltage tester. A suitable test system is the available I / O model from MTS Systems Corporation of Eden Prairie, Minnesota. The material testing system is provided with an appropriately sized load cell, for example, a 4.54 kilogram load cell, available from MTS Systems Corporation. The material test system is operated using the appropriate control program, for example TEST WORKS®, version 3.03 for WINDOWS®, available from MTS Systems Corporation.

With reference to Figure 8, a test specimen 150 is illustrated in the position suitable for testing in the material testing system 152. The material testing system 152 includes the upper and lower pneumatic grippers 154 and 155 where the Upper handles are movable vertically in relation to the lower handles. Each set of pneumatic grips 154 and 155 includes an opposite pair of rubber coated grip faces 156 that are adapted to move toward each other through an action of the pneumatic cylinders 158.

With further reference to Figure 9, test specimen 150 includes a test material 160 and a pair of the partial strip members 162. The test material 160 is cut using scissors so that it is rectangular with a long dimension. of 21.5 centimeters and a shorter dimension 166 of 7.6 centimeters. Two button pair holes, each measuring 2 centimeters in length were cut in the test material 160 using a knife (not shown). The holes for button are formed parallel to the long dimension 164 and are spaced by about 2 centimeters from a long edge and about 2 centimeters, such as 1.5 to 3 centimeters from each short edge. The buttonholes are reinforced with a film tape (not shown) of the type commonly used in commercial underwear that was adhesively bonded to test material 160.

The partial strip members 162, each one included a strip of elastic material 170 and a button 172. The elastic material 170 comprises a neoprene elastomer of 50 equilibrium at 23 ends per band of JPS Elastomerics, 4 strands of a white nylon thread of the number 70 and monofilaments of number 4 and number 8. Each strip of elastic material 170 had a length of more than 12.7 centimeters and a width of 3.81 centimeters (1.5 inches). The ends of the strip were joined ultrasonically to prevent fraying. The buttons 172 were fired over the end regions of the strips of the elastic material 170 so that the button centers were centered transversely and spaced from one end by 1.5 centimeters. Buttons 172 measured 22.2 millimeters in diameter and were purchased from Engineering Industries of Verona, Wisconsin, under the trade designation green membrane buttons.

The system voltage decay test was started by calibrating and preparing the equipment as specified by the manufacturer. The test specimen 150 was assembled by securing the buttons 172 and the button holes of the test material 162. The test specimen was then placed on the upper and lower pneumatic grippers 154 and 156 in the manner indicated in FIGS. 9. Specifically, the partial strip members 162 are secured between the grip faces 156 so that the length of the elastic strip material 170 of each grip face to the center of the nearest button is 12.7 centimeters. The distance between the jaws of the tension tester should be placed at 41.9 centimeters during placement so as not to prematurely lengthen the test specimen 150.

During the test, the lower pneumatic lugs 155 are held stationary while the upper pneumatic lugs 154 referred to in the crosshead move vertically in relation thereto. The crosshead is first moved to a starting position, which represents a separation distance that causes the materials to lose any large wrinkles or "loosened" and causes the buttons to move towards the outer limits of the button holes, without create too much preload. The load measured by the load cell should be from about 5 to about 20 grams in the starting position.

Four dimensions of length are noted and recorded, with respect to the starting position: a total length, which is the distance between the handle faces 156; a panel length which is the distance between the centers of the buttons and the lengths of strip number 1 and strip number 2, which represent the length of each strip from the grip face to the center of the button. The total length is determined by the voltage tester equipment; The panel length is measured by the operator using a ruler; and the lengths of strip number 1 and strip number 2 are both calculated using a formula: [(total length-panel length) / 2].

At this time, the control computer program starts. In general, the cross-head is raised at a constant rate of 500 millimeters per minute (mm / min) to an elongation of 50 percent, that is, one and a half (1.5) times the total length at the starting position. For example, for a total length in the position at the starting position of 41.9 centimeters, the test specimen 150 is elongated by 21 centimeters at a constant rate of about 25 seconds. The load measured by the load cell is recorded and recorded at: 0 seconds, which represents the pre-elongation; to 15 seconds; to 30 seconds; at 1 minute; At 5 minutes; 10 minutes away; 30 minutes; 30 minutes; at 40 minutes; to 50 minutes; and 1 hour. The total length of the panel length and the lengths of strip number 1 and strips number 2 are recorded and recorded immediately upon reaching 50% elongation; 30 minutes after starting the control computer program; and a 1 after the start of the control computer program. Note that the total length does not change after the crossed head reaches 50% elongation. A voltage decay value for the test material expressed as a percentage was calculated using the formula: [(load at 1 minute-load at 1 hour) / load at one minute] x 100.

EXAMPLE 1 A test material designated example 1 comprised a bonded laminated material consisting of a polyurethane film of 30 grams per square meter elastomeric placed in sandwich form between a pair of spunbonded fabrics of 28.7 grams per square meter formed from polypropylene fibers. The fabrics bonded with yarn were stretched and narrowed to 40% of their original width and then ultrasonically bonded through the film to each other. The material had an elongation measured at the peak load of about 186 percent.

Example 2 A test material designated example 2 comprised a stretched and tapered laminate which consisted of 16.9 grams per square meter of a spunbond fabric formed of polypropylene fiber fibers and 16.9 grams per square meter of the meltblown fabric formed of fibers of Polypropylene. The yarn-bound fabric was narrowed and stretched at 50% of its original width and then joined to the melt blown fabric by passing it through a compression pressure point. The material had an elongation measured at the peak load of about 121 percent.

Example 3 A test material designated example 3 comprising a laminate material bonded with reversibly stretched and stretched yarn consisting of 20.3 grams per square meter of yarn-bound fabric formed of polypropylene fibers and 15.2 grams per square meter of meltblown fabric formed of fibers of Polypropylene. The yarn-bound fabric was stretched and narrowed to 54% of its original width, heated, cooled, and then joined to the melt blown fabric by passing it through a compression clamping point. The material had a measured elongation at peak load of about 110 percent.

Example 4 A test material designated example 4 comprising a bonded and tapered laminate consisting of 40 grams per square meter of elastomeric meltblown filaments made from elastomeric block copolymers available from Shell Chemical Company and identified under the trademark KRATON G-2755, which were put in the form of a sandwich between a pair of fabric bonded with polypropylene yarn of 13.5 grams per square meter and joined together by passing through a compression clamping point, while the elastomer was being stretched. Such elastomeric structures are described in U.S. Patent No. 5,332,613 issued to Taylor et al. The material had a measured elongation at a peak load of about 235 percent.

Example 5 A test material designated example 5 comprising three layers of the material of Example 4 which were placed in sandwich form together and placed in the jaws of the tension tester. The material had a peak load that exceeded a load cell of 11.34 kilograms.

Example 6 (Comparative Example) A non-stretchable, relatively non-elastic comparison material designated Example 6 comprised an adhesive laminate of a woven fabric bonded with polypropylene yarn of 16.9 grams per square meter; a 0.23 mm thick polyethylene film that was treated with a crown on both sides; and a yarn-bonded fabric of 28.7 grams per square meter of non-crimped side-by-side polypropylene / polyethylene bicomponent fibers.

The results of this system voltage decay test for the materials of Examples 1-6 are summarized below in Tables 1-7. The change in length in the comparison material of Example 6 reported in Table 6 is believed to be due to the widening and / or tearing of the button holes and the tensioning of the material. The relatively shorter panel length of the material of Example 5 in the starting position was observed to be due to the curling of the material.

Table 1 System Voltage Decay Test: Lengths (millimeters) Example 1 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 126 167 126 419 After stretching 206 219 205 629 After 30 minutes 203.5 222 203.5 629 After 1 Hour 203 223 203 629 Table 2 System Voltage Decay Test: Lengths (millimeters) Example 2 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 126 167 126 419 After stretching 204 221 204 629 After 30 minutes 200 231 200 629 After 1 Hour 199 231 199 629 Table 3 System Voltage Decay Test: Lengths (millimeters) Example 3 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 126 167 126 419 After stretching 193.5 242 193.5 629 After 30 minutes 188 253 188 629 After 1 Hour 186 257 186 629 Table 4 System Voltage Decay Test: Lengths (millimeters) Example 4 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 126 167 126 419 After stretching 168.5 292 168.5 629 After 30 minutes 167 295 167 629 After l Time 166.5 296 166.5 629 Table 5 System Voltage Decay Test: Lengths (millimeters) Example 5 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 132 155 132 419 After stretching 217 195 217 629 After 30 minutes 216 197 216 629 After 1 Hour 216 197 216 629 Table 6 System Voltage Decay Test: Lengths (millimeters) Example 6 Test Material Time Strip # 1 Panel Strip # 2 Total At the beginning 126.5 166 126.5 419 After stretching 226 177 226 629 After 30 minutes 225 179 225 629 After 1 Hour 224.5 180 224.5 629 Table 7 System Voltage Decay Test: Load values (grams) Examples 1-6 Time Ei. 1 Ei. 2 Ei. 3 Ei. 4 Ei. 5 Ei. 6 0 sec 10.03 9.70 6.69 12.71 17.06 13.04 sec 391.05 372.59 330.12 300.92 407.12 448.24 sec. 502.49 502.44 460.79 365.03 521.87 585.91 1 min. 468.60 467.94 424.98 339.95 492.66 549.77 min 430.14 428.40 383.92 314.19 456.70 505.60 minutes. 416.82 412.35 367.59 304.79 442.40 489.03 min. 403.32 393.62 350.48 295.27 429.49 472.98 min. 397.97 384.62 342.45 289.61 421.16 464.81 40 min 390.54 380.62 342.45 289.61 421.16 464.81 50 min 385.93 373.55 328.97 281.63 412.02 452.74 1 hour 382.95 369.55 322.18 280.25 410.02 453.38 Value of 18 21 24 18 17 18 Decadence (%) From the data presented above, it is evident that even when all the materials showed some degree of stress decadence, they all maintained a retractive load and therefore they will hold an undergarment. The materials with lower decadence values, such as example 1, lose less of their retroactive force with time and retain the garment better over longer periods than other materials, such as example 3 which loses more strength of retraction over time. Materials with higher load values, such as Example 1, will also retain the garment better than other materials, such as example 4, which has a lower charge value (strength) retroactive) to begin with.

A tensile stress test of material an elongation of 50% was carried out to compare individual materials for use as expansion panels in the present invention. The test equipment is the same as that used in the system voltage decay test described above. Cad test specimen represents a material cut to maintain a width of 7.62 centimeters and a length of at least 18.7 centimeters. The test was started by calibrating to prepare the equipment as specified by the manufacturer. The test specimen was placed in the upper and lower pneumatic grippers 154 and 156 so that about one centimeter of the test specimen material is held between each of the handle faces 156. This results in a distance of material between the faces. of handle 156 d 12.7 centimeters.

During testing, the lowest pneumatic grips 155 are held stationary while the crosshead 154 moves vertically relative to this. The crosshead is moved first to a starting position, which represents a separation distance that causes the test specimen material to lose any large wrinkles "loosen" without creating too much preload. The load measured by the load cell should be around 5 to about 20 grams at the starting position.

The computer control program starts.

In general, the crosshead is raised at a constant rate d 500 mm / min to an elongation of 50 percent, that is, an average (1.5) times the total length of the material measured between the handle faces in the starting position . For example, for a total length in the starting position of 12.7 centimeters, the test specimen material is elongated 6.35 centimeters at a constant rate in about 7.6 seconds. The load measured by the load cell was recorded and recorded at 2.0 seconds, which represents the pre-elongation; 15 seconds; 30 seconds; 1 minute; 5 minutes; 10 minutes; 20 minutes; 30 minutes; 40 minutes; 50 minutes; 1 hour. A decay value of material tension at a 50 percent elongation for a test material, expressed as a percentage, was calculated using the formula: [(load at 1 minute - load at 1 hour) / load at 1 minute] x 100 .

Example 7 A test material designated to example 7 comprised a strip of elastic material of 3.81 centimeters by 12.7 centimeters comprising nylon, polyester and elastic materials that was purchased from Shelby Elastics, under the trade designation NP50. The material had a peak load that exceeded a load cell of 11.34 kilograms.

Example 8 A test material designated to example 8 comprised an elastomeric strip material of 3.81 centimeters by 12.7 centimeters comprising a 50-gauge neoprene elastomer at 23 ends per band of JPS Elastomerics; 4 threads of white nylon thread number 70; and monofilaments of number 4 and number 8. The test strip material had a peak load that exceeded a load cell of 11.34 kgm.

The results of the material tensile decay test at a 50 percent elongation for the materials of Examples 1-8 are summarized below in Table 8. Due to the low elongation of the material of Example 6, this n was extended to Full lengthening of 50 percent but rather to a lower value.

Table 8 Material Tension Decay Test at 50% Elongation Load Values (grams) Examples 1-8 Time Ei. 1 Ei. 2 Ei. 3 Ei. 4 Ei. 5 Ei. 6 Ei. 7 Ei. 8 0 sec 12.0 9.5 9.4 12.0 20.4 7.5 14.4 13.6 sec 672.3 691.0 328.3 294.9 884.5 4746.4 443.3 479.1 sec. 637.0 620.7 297.8 282.8 850.3 4505.2 431.8 464.7 1 min. 611.0 572.0 274.4 273.7 823.7 4343.0 422.3 455.6 min 563.9 479.8 228.9 257.2 778.1 3962.5 403.4 431.9 minutes. 545.0 445.3 212.3 251.3 760.3 3714.0 393.7 422.9 min. 527.0 141.0 197.4 243.5 741.2 3477.5 385.6 411.6 min. 516.7 396.2 188.0 240.2 735.7 3346.6 379.7 406.0 40 min 510.8 383.7 180.7 235.6 720.6 3256.7 375.6 402.3 50 min 506.3 374.6 177.2 234.6 715.5 3193.2 371.6 398.6 1 hour 500.6 367.1 172.9 231.1 710.8 3137.6 369.7 396.6 Value of 18.1 35.8 37.0 15.6 13.7 27.8 12.5 12.9 Decay (%) A tensile stress test of a 100 percent elongation material was also carried out to compare various materials to be used as the pull members in the present invention. This test is the same as the tensile decay test of material at an elongation of 50 except that the crosshead was raised at a constant rate of 50 mm / min at an elongation of 100 percent, that is, twice the total length of the test material between the handle faces in the starting position. Therefore, for a total length in the start position of 12.7 centimeters, the test specimen material is lengthened 12.7 at a constant rate in about 15.2 seconds. A d value decay of material tension at 100% elongation for the test material, expressed as a percentage, is calculated using the formula: [(load at 1 minute - load at 1 hour) / load at minute] x 100.

The results of the decay test of material tension at a 100 percent elongation for the materials of Examples 7 and 8 is summarized below in Table 9.

Table 9 Decay of Material Tension at an Elongation of 100% Load values (grams) Examples 7 and 8 Time Example 7 Example 8 0 seconds 16.4 20.3 15 seconds 663.5 719.3 30 seconds 617.9 673.7 5 minutes 562.5 610. 10 minutes 547.5 593.3 20 minutes 531.7 577.2 30 minutes 523.5 566.9 40 minutes 516.7 560.8 50 minutes 513.5 556.1 1 hour 509.2 550.7 Decay value 17.7 15.4 (%) The data in Tables 8 and 9 illustrate some of the properties of the material that are believed to be important in relation to the present invention. Examples 1-6 (Table 8) are materials, which can be used as stretchable and breathable expansion panel materials. These materials were stretched to 150 percent of their original length and then stopped falling. Examples 7 and 8 in Table 8 are typical of the materials used for peelable elastic strips. Note that these have lower voltage decay values than the panel materials, indicating that these will tend to be more resistant to the decay of the elastic over time. The expansion panel material, for example one of examples 1-6. it works in series with the strip material, for example, one of examples 7 and 8 and it will reach an equilibrium value. As the expansion panel material tension decays, the strips will tend to decay less, the suspension and tensioning system will be retracted and maintained.

This of course prevents the undergarment from falling off, provided that the peak load resulting from the strip and the expansion panel system is greater than the downward force on the used cloth and as long as the length of the strip and the system The expansion pane is not so long that it easily extends to the point where it falls out of the user.

Comparative Example 6 (Table 8) shows what happens when the expansion panel material is pulled beyond the elongation limit. The destruction of the expansion panel material begins when the forces rise to a very high level, well above that which the strip can hold. In the case of Comparative Example 6, the material could not extend 150 percent of its initial length but only to a smaller value. The strips of examples 7 and 8 were lengthened to 50 percent elongation, however, they could extend the expansion panel materials of examples 2, 3 and 4 plus 50 percent because in one hour the strips had a greater retraction force. Because the panel materials of examples 1 and 5 have forces greater than those of the strips, these will not stretch to an elongation of 50 percent by the elongated strips only 50 percent. Referring to Table 9, however, note that the elongated strips 100 percent have sufficient strength to stretch the expansion panel material of Example 1 to 50 percent. Because the expansion panel material of Example 5 at an elongation of 50 percent still has a retraction force greater than that of the 100 percent strips (Table 9), so that an equilibrium force is generated, the strips must have an elongation of more than 100 percent and the expansion panel material of Example 5 (Table 8) less than 50 percent.

In summary, depending on the generated retraction forces and the user's body size, the strip and expansion panel materials will be stretched until they reach an equilibrium force where the extended strip and expansion panel materials generate equal forces. When the tension of the materials decays, this relation will change. Materials with higher decay values will lose strength and lengthen while those with lower decay values will tend to retract and therefore maintain tension in the system.

Test Procedures Procedures of Water Vapor Transmission Rate The water vapor transmission rate (WVTR) of a fabric gives an indication of how comfortable a fabric is to be used. A suitable technique to determine the water vapor transmission rate of a material is the ASTM Standard E96-80 test. For the purposes of the present invention, circular samples measuring 3 inch diameter s cut out of the test material and a control material which is a piece of CELGUARD® 2500 films from Hoechst Celanes Corporation of Sommerville, New Jersey, United States of America. America. The CELGUARD® 2500 is a microporous polypropylene film 0.0025 centimeters thick.

Five samples were prepared for the test and the control materials. The test plate is a Vapometer No. 60-1 distributed by the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania, United States of America. About 100 milliliters of water was poured onto each Vapometer tray and each of the samples of the test material and control material were placed through the open top portions of the individual trays. Do not apply grease unless contamination can be prevented. The bolted flanges are tightened to form a seal along the edges of the trays, leaving the associated test material or control material exposed to the ambient atmosphere over a circle of 6.5 centimeters in diameter having an area exposed to around 33.17 square centimeters. The trays are placed in a forced oven opposite to 32 ° C for 1 hour at equilibrium. The oven is a constant temperature oven with the external air circulating through it to prevent the accumulation of water vapor inside. A suitable forced air furnace is, for example, a Blue M Power-O-Matic furnace 60 distributed by Blue M Electric Company of Blue Island, Illinois, United States of America. When the balance was complete, the trays were removed from the kiln, weighed and immediately returned to the kiln. After 24 hours, the trays were removed from the oven and weighed again. The preliminary test water vapor transmission rate value was calculated as follows: WVTR test = (weight loss grams over 24 hours x 315.5 (g / m2 / 24 hours) The relative humidity inside the oven was not specifically controlled.

Under predetermined set conditions of 32 ° C and relative humidity, the water vapor transmission rate for CELGUARD® 2500 material has been defined as being 5000 gm / m2 / 24 hours. Therefore, the CELGUARD® 2500 is run as a control sample with each test and the preliminary test values are corrected to the established conditions using the following equation: WVTR = (Test of WVTR / control CELGUARD® WVTR) x 5000 gm / m2 / 24 hr.

Liquid Transmission Test The liquid transmission test measures the lateral movement of distilled water at room temperature through a material, which is supported by a stainless steel plate covered with vinyl. The plate 180, which is shown in Figure 10, has an upper surface 182 with an edge 184. A container 186 of distilled water is placed below the edge 184 of the plate 180 so that the distance between the upper surface and the Water level is 1 centimeter. Plate 180 has lines 190 and 192 marking 5 10 centimeters, respectively from edge 184 of the plate.

In the test, 5 specimens 194 of the material to be tested were mounted from 50.8 by 152.4 millimeters on the upper surface of the level plate. A narrow end of each specimen was weighed and placed on the edge of the plate within the liquid. When the sample ends are thrown into the liquid, a timing was started.

The progress of the frontal liquid was observed and the time was measured to the nearest 0.1 minute, it was recorded when starting the liquid front to cross 5 and 10 centimeters. If the liquid front did not reach the 10 centimeter mark in 30 minutes, the test was stopped and the maximum distance was recorded. The transmission value for a material is the average distance traveled after 30 minutes for the 5 specimens tested.

The above detailed description has been given for the purpose of illustration. A number of modifications and changes may be made without departing from the spirit of the scope of the present invention. For example, the alternate or optional features described as part of an embodiment may be used to give yet another embodiment. Additionally, named components can represent parts of the same structure. Therefore, the invention should not be limited by the specific embodiments described but only by the claims.

Claims (35)

R E I V I N D I C A C I O N S

1. An absorbent article comprising: a garment having a longitudinal axis, a first waist region, a second waist region, a crotch region in the middle and interconnecting the first and second waist regions, a first waist region adapted to stretch in a direction essentially perpendicular to the waist longitudinal axis; Y a pair of spaced elastomeric strip members, each having opposite ends adapted to be attached to the waist regions.

An absorbent article comprising: a garment having a longitudinal axis, a first waist region, a second waist region and a crotch region in between and interconnecting the first and second waist regions, the first and second waist regions are adapted to stretch in one direction essentially perpendicular to the longitudinal axis; and a pair of spaced elastomeric strip members, each having the opposite ends adapted to be attached to the waist regions.

3. The absorbent article as claimed in clauses 1 or 2, characterized in that the first region comprises an elastomeric material.

4. The absorbent article as claimed in clause 3, characterized in that the second region comprises an elastomeric material.

5. The absorbent article as claimed in clause 4, characterized in that the elastomeric materials of the first and second belt regions have different elastomeric properties.

6. The absorbent article as claimed in clause 1, characterized in that the first waist region comprises an expansion panel adapted to elongate in a direction essentially perpendicular to the longitudinal ej.

7. The absorbent article as claimed in clause 2, characterized in that each of the first and second waist regions comprises an expansion panel adapted to extend in a direction substantially perpendicular to the longitudinal axis.

8. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion panel has a non-extended width and is adapted to have an extended width that is greater than the non-extended width when subjected to a force perpendicular to the longitudinal axis.

9. The absorbent article as claimed in clause 8, characterized in that the extended width is at least about 110 percent of the non-extended width.

10. The absorbent article as claimed in clause 8, characterized in that the extended width is at least about 125 percent of the non-extended width.

11. The absorbent article as claimed in clauses 6 or 7, characterized in that each strip member has a width dimension and the expansion panel has a length dimension that is at least 200 percent of the dimension of width of the strip member.

12. The absorbent article as claimed in clause 11, characterized in that the length dimension of the expansion panel is at least 250 percent of the width dimension of the strip member.

13. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion panel has a length of at least about 5 centimeters.

14. The absorbent article as claimed in clause 13, characterized in that the expansion panel has a length dimension of at least about 10 centimeters.

15. The absorbent article as claimed in clause 13, characterized in that the expansion panel has a length dimension of from about 12.5 to about 20 centimeters.

16. The absorbent article as claimed in clauses 6 or 7, characterized in that the strip members have a voltage decay value and the expansion panel has a voltage decay value that is greater than that of the strip members. .

17. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion part is adapted to extend and remain in an extended condition during use.

18. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion part forms an end flap that is placed on and at least partially not adhered to the crotch region d.

19. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion part comprises a reinforcement segment in which the expansion part is generally folded in thickness.

20. The absorbent article as claimed in clause 19, characterized in that the prend includes fasteners placed in the reinforced segment adapted to releasably engage the strip members.

21. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion part comprises a material capable of breathing

22. The absorbent article as claimed in clauses 6 or 7, characterized in that the expansion panel has a transmission rate of less than about 3 centimeters per 30 minutes.

23. The absorbent article as claimed in clauses 1 or 2, characterized in that the garment is adapted to have a generally uniform width dimension across the crotch and waist regions when it lies flat and stretched longitudinally.

24. The absorbent article as claimed in clause 2, characterized in that the garment is adapted to have a rectangular shape when placed flat and stretched longitudinally and a dog bone or hourglass shape when placed flat and longitudinally and transversally stretches.

25. The absorbent article as claimed in clauses 1 or 2, characterized in that the first waist region is adapted to assume an approximately trapezoidal shape when subjected to a force perpendicular to the longitudinal axis.

26. The absorbent article as claimed in clauses 1 or 2, characterized in that the crotch region is adapted to be essentially perpendicular not extendible to the longitudinal axis.

27. The absorbent article as claimed in clauses 1 or 2, characterized in that the first waist region is adapted to elongate in a direction that forms an angle with the longitudinal axis of between about 70 and 90 degrees.

28. The absorbent article as claimed in clause 27, characterized in that the first waist region is adapted to elongate in a direction that forms an angle with the longitudinal axis of between about 80 and 90 degrees.

29. The absorbent article as claimed in clauses 1 or 2, characterized in that the crotch region comprises a side-to-body lining, a sweep to moisture and an absorbent structure placed between the side-to-body and the barrier to the body. the moisture, the absorbent structure and the moisture barrier end longitudinally in the first and second waist regions.

30. An absorbent article comprising: a garment having a longitudinal axis, a first waist region, a second waist region and a crotch region in the middle and interconnecting the first and second waist regions, the garment comprises: an expansion panel placed in both the first and second waist regions and adapted to elongate in a direction essentially perpendicular to the longitudinal axis; Y an absorbent structure placed on the expansion part in the crotch region; Y a pair of spaced elastomeric strip members, each having the opposite ends adapted to be joined to the waist regions.

31. The absorbent article as claimed in clause 30, characterized in that the expansion panel has a length essentially equal to a longitudinal extension dimension of the garment.

32. The absorbent article as claimed in clause 30, characterized in that the expansion panel comprises a material impermeable to liquid.

33. The absorbent article as claimed in clause 30, characterized in that the storage assembly comprises a moisture impermeable liquid barrier attached to the expansion panel.

34. The absorbent article as claimed in clause 30, characterized in that it comprises a second expansion panel adapted to elongate in a direction substantially perpendicular to the longitudinal axis, the absorbent structure being placed in the form of a sandwich between the expansion panels.

35. The absorbent article as claimed in clauses 30 or 34, further characterized in that it comprises essentially non-stretchable zones placed between the crotch region and the waist regions. SUMMARY An absorbent article includes a garment having the opposite waist regions separated by a crotch region. At least one of the belt regions includes an expansion panel adapted to extend in a direction essentially perpendicular to the longitudinal axis of the garment. The absorbent article also includes a pair of elastomeric strip members that are adapted to be attached to the waist regions.