MXPA97009513A - Apparatus for measuring the recovery of crushing of an absorbe article - Google Patents

Abstract

An apparatus for measuring the recovery of crushing of an absorbent article as well as the article itself is described. The apparatus includes a tester having the first and second arms, at least one of which is movable. The apparatus includes a first frame member attached at one end to the first arm of the tester. The first frame member has a shoulder with a first rod extending outwardly therefrom. The apparatus further includes a second member attached at one end to the second arm of the tester. The second frame member has a shoulder with a second rod extending outwardly therefrom. The first and second frame members are interleaved so that the first and second rods are spaced apart to allow the absorbent article to be placed therebetween. In addition, the first frame member relative to the second frame member causes the absorbent article to be squeezed in a sideways direction between the shoulders. By reversing the relative movement of the frame members, the absorbent article is able to expand outwardly towards its original transverse dimension. The amount of recovery to the sides is measured as the value of "recovery from crushing". The absorbent article includes a liquid permeable cover, a liquid impervious separator and an absorbent placed between the cover and the separator. The absorbent article has a crush recovery value of at least about 15 millimeters, a wet load value of at least about 300 grams, a tension value of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeter

Description

APPARATUS FOR MEASURING THE RECOVERY OF CRUSHING OF AN ABSORBENT ARTICLE FIELD OF THE INVENTION This invention relates to a thin absorbent article for absorbing and retaining the human exudate, an apparatus for measuring the recovery from crushing of an absorbent article, and to the article itself. More specifically, this invention relates to a thin sanitary napkin which can reduce the run-off of body fluid during use.

BACKGROUND OF THE INVENTION Absorbent articles such as sanitary napkins, incontinent garments, incontinent shields, and the like, are designed to be worn on the side of a woman's pudendal to absorb body fluids such as menstrual fluids, urine, blood and other droppings. Some of these products are designed with sufficient absorbent capacity to be used during the menstrual period while others are intended to be used before and after the menstrual period to absorb small amounts of body fluid. Currently, thin absorbent articles having a general thickness of about five millimeters or less are preferred by a large number of women.

Younger women in particular want to use thin absorbent articles because they are more discreet under tight fitting clothing and do not restrict body movement as do some thick pads.

In order to provide the consumer with thin absorbent articles which also contain sufficient absorbent capacity, some manufacturers have added superabsorbents to their products. While superabsorbents do not have the ability to absorb larger amounts of body fluid if it is provided with enough time to absorb fluid, most suffer from two major disadvantages. First, many superabsorbents exhibit slow fluid intake rates which provide little benefit in reducing runoff during periods when the absorbent article is discharged with a large amount of body fluid. This problem of runoff becomes more pronounced in thin sanitary napkins because any body fluid that stagnates on the side-to-body cover has a greater tendency to squeeze out of the side edges before it can be absorbed into the underlying absorbent. . Second, most superabsorbents are expensive and their use increases the overall cost of the finished item.

Another deficiency usually exhibited by thin absorbent articles is that some are relatively stiff and therefore feel uncomfortable when placed against the thighs of the wearer. Such a characteristic becomes more pronounced on a woman's anatomy that have a very narrow distance between the thighs. Preferably, the thin absorbent articles should be both docile and comfortable to use.

Now, the thin absorbent article has been invented which contains a multi-layer absorbent structure which reduces runoff and is very convenient to use.

SYNTHESIS OF THE INVENTION Briefly this invention relates to a thin absorbent article, such as a thin sanitary napkin, which is designed to reduce the runoff of body fluid during use. An apparatus for measuring the recovery of crushing of an absorbent article is also described. The absorbent article includes a liquid permeable cover, a liquid impervious separator and an absorbent placed between the cover and the separator. The absorbent article has a crush recovery value of at least about 15 mm, a wet load value of at least about 300 grams, a tension value of less than about 100 grams / millimeter and a thickness of less than about 5 millimeters.

An apparatus for measuring the recovery of crushing of an absorbent article is also described. The apparatus includes a tester having the arms first and second of which at least one is mobile. The apparatus also includes a first frame member attached at one end to the first arm. The first frame member has a shoulder with a first rod extending outwardly therefrom. The apparatus further includes a second frame member attached at one end to the second arm. The second frame member has a shoulder with a second rod extending outwardly therefrom. The first and second frame members are interconnected so that the first and second rods or rods are spaced apart to allow an absorbent article to be placed therebetween. The movement of the first frame member away from the second frame member causes the absorbent article to be squeezed in a sideways direction between the shoulders. The applied force is then removed and the article is trained to expand outward to its original transverse dimension. The amount of recovery to the sides is referred to as "recovery from crushing" and this value is measured and recorded.

The general object of this invention is to provide a thin absorbent article for absorbing and retaining the wet exudate and an apparatus for measuring the recovery from crushing of an absorbent article. A more specific object of this invention is to provide a thin sanitary pad which can absorb and retain body fluid, including menstrual fluids while reducing the flow of body fluid during use.

Another object of this invention is to provide a thin absorbent article which has a thickness of less than about 5 millimeters.

A further object of this invention is to provide an apparatus for squashing to the sides and then measuring recording the amount that the absorbent article could recover.

Still another object of this invention is to provide a thin absorbent article having an absorbent formed of a multi-layered structure of a fine pore fabric.

Still further, an object of this invention is to provide a thin and inexpensive absorbent article which is devoid of superabsorbent.

Other objects and advantages of the present invention will be more apparent to those skilled in the art in view of the following description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partially sectioned perspective view of a thin absorbent article having a multi-layer absorbent structure.

Figure 2 is a cross-sectional view of the thin absorbent article taken along line 2-2 of Figure 1.

Figure 3 is a cross-sectional view of another embodiment of a thin absorbent article having a multi-layer absorbent structure formed of a plurality of vertically stacked sheets.

Figure 4 is a schematic representation of another embodiment of the multi-layer absorbent structure showing a plurality of sheets stacked vertically having the fluid passages formed therein.

Figure 5 is a schematic representation of another embodiment of the multi-layer absorbent structure showing a single sheet bent in an accordion shape and having a polyhedron configuration with a central fluid conduit formed therein.

Figure 6 is a schematic representation of another embodiment of the multi-layer absorbent structure showing a plurality of vertically stacked sheets arranged in a rectangular configuration with each sheet having at least one slit formed therein.

Figure 7 is a schematic representation of yet another embodiment of the multi-layer absorbent structure showing a plurality of vertically stacked sheets arranged in a triangular configuration with each sheet having at least one slit formed therein.

Figure 8 is a front elevational view of an apparatus in an open position showing a non-crushed absorbent article positioned between the first and second frame members and fastened to a tester.

Figure 9 is a front elevated view of the apparatus in a closed position showing the absorbent article having been squashed sideways between the first and second frame members.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY Referring to Figures 1 and 2, a thin absorbent article 10 is shown which is shown as a sanitary napkin. A sanitary napkin is designed to be used by a woman to absorb body fluids such as menstrual fluids, blood, urine and other excreta. A sanitary napkin is also mentioned as a catameneal pad or a feminine pad. Although the thin absorbent article 10 will be described with reference to a sanitary napkin, it may also encompass other items such as the incontinent garment, incontinent shields, and the like. In addition, the thin absorbent article 10 can be used either alone or in combination with menstrual panties, underwear or specially designed belts, straps or underwires.

By "thin absorbent articles" is meant articles having a general thickness of less than about 5 millimeters (mm). More preferably, the thin absorbent articles will have a thickness of between about 2 millimeters to about 5 millimeters. The precise method used to determine the thickness of a thin absorbent article will be described in more detail below.

The thin absorbent article 10 when used in the form of a sanitary napkin 10 is an elongate article having a central longitudinal x-axis, denoted X-X and a central transverse axis and denoted Y-Y. The transverse x-axis is oriented perpendicular to the longitudinal x-axis. The sanitary napkin 10 has a length of between about 150 millimeters to about 300 millimeters and a width of between about 50 millimeters to about 125 millimeters. The sanitary napkin 10 may have a generally rectangular shape with rounded ends, or it may have an elongated oval shape, an hourglass shape, a dog bone shape, a runway shape or other configuration.

The sanitary napkin 10 may include a liquid permeable cover 12, a liquid impervious separator 14 and an absorbent 16 placed between the cover 12 and the separator 14. Typically, the cover 12 and the separator 14 cooperate to wrap the absorbent 16. cover 12 is designed to make contact with the wearer's body and can be constructed of a woven or non-woven material which is easily penetrated by body fluid. The cover 12 can also be either natural or synthetic fibers. Suitable materials include carded and bonded polyester fabrics, polypropylene, polyethylene, nylon or other heat-stable fibers. Other polyolefins such as copolymers or polypropylene and polyethylene, linear low density polyethylene, finely perforated film fabrics and pure materials also work well. A particular preferred material is a composite of a perforated thermoplastic film placed on top of a nonwoven fabric material. Such a composite material can be formed by extruding a polymer onto a spunbond web to form an integral sheet. An example of this is a perforated thermoplastic film bonded to a spunbonded material. This material exhibits a smooth and smooth outer surface which is not irritating to the wearer's skin and still has a cushioned feeling due to its volume.

Another preferred material for cover 12 is a polypropylene spunbonded fabric. The fabric can contain between about 1 percent to about 6 percent titanium dioxide pigment to give it a clean white appearance. A uniform thickness of spun bond is desirable because it will have sufficient strength, after being drilled in the longitudinal direction, to resist being torn or pulled and separated during use. The most preferred polypropylene fabrics have a weight of between about 18 to about 40 grams per square meter. An optimum weight is between about 30 to about 40 grams per square meter.

The liquid impervious cover 12 may also contain a plurality of openings 18 formed therethrough. The openings 18 can be nged uniformly or randomly over the entire surface of the cover 12 or on a part of the surface of the cover 12. For example, the openings 18 can be nged in a band having a width of between about 0.5 of a inch to about 2 inches (about 12.7 millimeters to about 50.8 millimeters) which extends along the central longitudinal axis x. The band of openings 18 can run to the full length of the sanitary napkin 10 or be present over only a part of the full length. The openings 18 are intended to facilitate movement of the body fluid which is deposited on the cover 12 to penetrate downwardly to the absorbent 16.

The size and shape of the openings 18 may vary, however, for the particular menstrual fluid, the openings 18 may have a round or circular cross-sectional area. Other forms such as oval an ellipse, etc. can be used. Generally each of the openings 18 will be a hole, a gap, a slit, a hole, a space, a partition, or an opening that will vary in size from about 0.3 millimeters to about 5.0 millimeters. At least one of the openings 18 formed in the cover 12 should have a diameter within this range. Preferably a majority of the openings 18 will have a diameter greater than about 0.3 millimeters. If an opening 18 is not round, so that it does not have a diameter then the surface area of the opening must be equivalent to or greater than that of a circle having a diameter of about 0.3 millimeters. In addition, each of the openings 18 can be spaced apart from an adjacent opening 18 by an equal distance or by several distances. The openings 18 can be spaced from an adjacent opening 22 by almost any distance but this distance should be at least about 0.3 millimeters or more. The size of the opening 18 can affect to some extent the closeness to which an adjacent opening 18 can be located. Although the openings 18 are not essential, they provide a functional advantage which can not be ignored. The presence of the openings 18 helps the body fluid to migrate rapidly into the absorbent 16 and thus makes the sanitary towel 10 very comfortable for use. By allowing the body fluid to pass rapidly through the cover 12, the absorbent article 10 tends to remain drier along with the wearer's body. The rapid migration of the body fluid into the absorbent article 10 also helps to reduce fluid runoff.

The liquid impervious separator 14 allows air or steam to pass out of the sanitary napkin 10 while blocking the passage of fluid from the body. The separator 14 can be made of any material having these properties. The separator 14 can also be constructed of a material that will block the passage of the vapor as well as the fluids if desired. A good material for the separator 14 is a micro-etched polymeric film, such as polyethylene or polypropylene. Two-component films can also be used. A preferred material is a polyethylene film. More preferably, the separator 14 will be composed of a polyethylene film having a thickness in the range of from about 0.5 millimeters to about 2.0 millimeters.

The separator 14 can be cut to a size and shape that will coextensive with the cover 12. When this is done, the cover 12 and the spacer 14 can be joined in a facing contact to form a peripheral sealed sanitary towel as shown in the Figure 1. It is also possible to wrap the towel 12 completely around the absorbent 16, as shown in Figure 3, and then to adhere the cover 12 to the upper surface of the frame 14. Alternatively, the separator 14 can be wrapped along the side edges of the absorbent 16 and then the cover 12 can be wrapped completely around both the separator 14 and the absorbent 16. These and other variations are known to those skilled in the art of absorbent articles.

The cover 12 and the separator 14 will cooperate to retain the absorbent 16 therebetween. It should be noted that the spacer 14 does not have to be attached directly or secured to the cover 12 but can be attached to an intermediate member which in turn attaches to the cover 12. In either case, the absorbent 16 is in the middle of the cover 12 and the separator 14.

Referring again to Figures 1 and 2, a transfer layer 20 having a plurality of openings 22 formed therethrough is placed between the cover 12 and the separator 14. Preferably, the transfer layer 20 is placed immediately below the cover 12 and is in direct face-to-face contact with it. Even when the transfer layer 20 is optional, when present, it provides a good fluid movement down from the cover 12 to the absorbent 16. The downward movement of the fluid is parallel to a vertical axis z denoted by Z-Z. The z axis is arranged perpendicularly in relation to the x and y axes.

The transfer layer 20 may be constructed of a material that will provide good fluid transfer. Typical materials which can be used for the transfer layer 20 are spunbond, coform and carded fabrics. A useful material which was tested was a spun bond of 0.95 ounces per square yard (osy) which was peach colored. The spun bond contained a plurality of openings 22 having a diameter of about 3.18 millimeters which were formed on a grid spacing of about 12.7 millimeters by about 9.26 millimeters. Another preferred material is meltblown polypropylene having a weight between about 0.2 ounces per square yard to about 2.0 ounces per square yard.

It has been noticed that when the transfer layer has a fibrous, frictional hairy surface that will adhere to the cover 12 and assist in the transfer of fluid from the cover 12 to the absorbent 16. The transfer layer 20 can be treated to render it hydrophilic. The transfer layer 20 can be a single sheet of about 1.0 ounce per square yard to about 2.0 ounces per square yard or can be folded to achieve that weight. The thickness of the transfer layer 20 is generally between about 1 millimeter and 5 millimeters. The apparatus or perforations 22 can be uniformly or randomly arranged across the surface of the transfer layer 20. The perforations 22 are aligned coaxially with or off-center from the openings 18 formed in the cover 12. The openings 22 can be smaller , larger or the same size as the openings 18 which are formed in the cover 12. Generally, each of the perforations 22 will be a hole, a gap, a slit, a hole, a space, a partition or an opening that It will vary in size from around 0.3 mm to around 5.0 mm. Preferably, a majority of the perforations 22 will have a diameter greater than about 0.3 millimeters. If the perforation 22 is not round, so that it has a diameter, then the surface area of the opening must be equivalent to or greater than that of a circle having a diameter of about 0.3 millimeters. The openings 22 can be spaced from an adjacent opening 22 by almost any distance but this distance must be at least about 0.3 millimeters or more. The size of the opening 22 can affect to some extent the closeness at which an adjacent opening 22 can be located.

Like the openings 18 formed in the cover 12, the openings 22 can vary in size and shape. The openings 22 can have a round, circular, oval elliptical or some other cross-sectional area. It is also possible to form the openings 22 as slits which open in use in a larger size to allow the flow of fluid therethrough. For most applications, the openings 22 must be round holes.

The transfer layer 20 can also be colored a different color from that of the cover 12 and / or of the absorbent 16. It has been found that a light blue, pink or peach is desirable since these are pleasant feminine colors. The use of a color different from that of the absorbent 16 also presents an objective for the user and will indicate when the sanitary napkin 10 was placed inappropriately in relation to the vagina.

The absorbent 16 is positioned between the transfer layer 20 and the separator 14. The absorbent 16 is a multi-layered structure having at least one fluid conduit 28 formed therein. The absorbent 16 is free or devoid of any superabsorbent material. The absorbent 16 can be formed of a single sheet 24, of an absorbent material which is folded on itself, such as an accordion shape to obtain a multi-layered structure. The actual method of bending may vary but the idea is to obtain a multi-layer structure having from between about 5 to about 30 vertically stacked horizontal layers. Preferably, the folded sheet 24 will contain from about 7 to about 15 vertically stacked layers. The absorbent 16 can be made of any suitable absorbent material including wood pulp fluff, rayon, cotton, and melt blowing polymer, such as polyester, polypropylene or coform. The coffer is a combination formed by meltblown air of meltblown polymer, such as stable fibers of polypropylene and absorbent such as cellulose. The absorbent material identified above should be formed into a sheet, cloth or tissue structure and should not be used in a loose fibrous form as in the case of many commercially available thick sanitary napkins. A preferred material is the wood glue which has formed on a tissue sheet due to its low cost at its relative ease to be made and it has good absorbency.

The absorbent 16 can also be a composite material consisting of a hydrophilic material which can be formed of several natural or synthetic fibers, of wood pulp fibers, of regenerated cellulose fibers or of cotton fibers or a mixture of pulp and other fibers . A preferred material is a fine-pored fabric such as a tissue dried in air and placed wet. The absorbent 16 may also comprise other well known materials used in the absorbent articles including cellulose fibers, rayon fibers, cellulose sponge, hydrophilic synthetic sponge, such as polyurethane and the like.

The tissue when used, this can vary in weight basis, thickness, bulk density, and so on. A preferred basis weight is about 30 grams per square meter (gsm) a preferred thickness is about 0.25 millimeters, and an apparent density is about 0.12 grams per cubic meter. The tissue can be of any size and shape, even when for a sanitary napkin, a rectangular configuration with or without rounded corners works well. For a typical sanitary napkin 10, each tissue sheet 24 may have dimensions ranging from about 50.8 millimeters to about 304.8 millimeters in length and from about 25.4 millimeters to about 127 millimeters wide. If the tissue sheet 24 is cut or sliced and then reassembled into a multi-layer absorbent structure 16, it is possible to form the tissue sheet 24 to almost any dimension. It should be noted that each sheet of tissue 24 may be of a single stratum or of two or more layers which are assembled to form a single sheet 24. The strata may be assembled by heat and / or pressure, by mechanical means and so on.

The absorbent 16 can also be constructed of a melt-blown olefin fabric. Regardless of the type of material used, the absorbent sheets 24 can be treated to be hydrophilic.

Referring again to Figures 1 and 2, the multi-layer absorbent structure can be wrapped in a tissue sheet 30. The tissue sheet 30 is beneficial in maintaining and retaining the multi-layer absorbent structure together.

Referring to Figure 3, an alternate arrangement for an absorbent article 32 is shown. Absorbent article 32 is again shown as a sanitary napkin having a liquid-permeable cover 34 and a liquid-impermeable separator 36 which cooperate to wrap an absorbent 38. The cover 34 still contains the perforations 40 which function as the openings 18 do in Figures 1 and 2. However, a notable difference is that the cover 34 is completely wrapped around both the separator 36 and the absorbent 38. A second difference is that the separator 36 has the longitudinal side edges 42 and 44 which extend upwardly along the sides of the multi-layer absorbent structure 38. The lateral edges oriented upwards 42 and 44 help to prevent run-off of the sanitary towel fluid 32 during use. A third difference of the embodiment shown in Figures 1 and 2 is that the absorbent 38 is formed of a plurality of individual sheets 28 of the absorbent material. The sheets 28 are stacked vertically to form a plurality of horizontal layers. The number of sheets 28 in the multi-layer absorbent structure 38 can vary from 5 to 30. Preferably, the number of sheets 28 will vary from 7 to 15, and more preferably, the number of sheets 28 will vary from about 8 to 12. Each sheet 28 can be a layer of a tissue which has the same thickness, physical properties and functional characteristics as an adjacent layer. Alternatively, each sheet can be constructed to have different physical properties, a different thickness and / or different functional characteristics as an adjacent layer. For ease of manufacture, all sheets 28 must be essentially the same.

In Figure 3, the multi-layer absorbent structure has a central duct 46 formed therein which is aligned coaxially with the z-axis. The overall size and shape of each sheet 28 can vary as the overall width of each sheet can. The application arrangement for the multiple sheets, the depth of the duct 46, and so on. Preferably, the duct 46 will extend completely through all the sheets 28 and optionally will extend only through a part of the total number of sheets 28.

Positioned at the base of the multi-layer absorbent structure 38 is one or more layers of the absorbent tissue 48. In Figure 3, two layers of the absorbent tissue 48 are present. The tissue layers 48 are sized and shaped to extend to the surface area of the multi-layer absorbent structure and provide a reservoir for the fluid within the sanitary napkin 32.

Turning to Figures 1 and 2, the multi-layer absorbent structure 16 has the central conduit 26 formed there which is aligned perpendicularly with the x-axis and is aligned coaxially with the z-axes. This central duct 26 communicates by means of the fluid that several ducts 50 are present between each pair of bent sheets 24. The fluid ducts 50 are formed by folding the sheet 24 to obtain the multi-layer absorbent structure 16. The central duct 26 it also communicates with a duct 52 formed between the upper surface of the folded sheet 24 and the lower surface of the wrapped tissue layer 30 and also with a duct 54 formed between the upper surface of the wrapped tissue layer 30 and the lower surface of the transfer layer 20. Due to the presence of the conduits 26, 50, 52 and 54, any body fluid which is deposited on the upper surface of the cover 12 will be able to flow downwards and towards the dies in the axes x and y to be rapidly distributed to the entire surface area of the multi-layer absorbent structure 16. This unique feature allows a plurality of sheets of thin tissue having a general thickness below 5 millimeters to have an absorbent capacity of at least 20 grams, preferably at least 22 grams, and more preferably more than 25 grams. The total absorbent capacity of the sanitary napkin 10 can be measured using the test method described later in this application.

The conduits 26, 50, 52 and 54 are formed and arranged so that any point within the absorbent 16 is at a distance of less than about 2 millimeters, and preferably less than about 1 millimeter, out of one of the other conduits. This allows the body fluid to be directed through the absorbent 16 and into the fluid the ability to reach the opposite side edges, the longitudinally spaced ends and the four corner areas of the absorbent 16 very quickly.

The aforementioned absorbent capacity for sanitary napkin 10 is obtained without the use of any superabsorbent. By superabsorbent it is meant that those superabsorbent materials usually employed in sanitary napkins, diapers, training pants, etc. including the hydroxy functional polymers, the hydrogel-forming polymers, the crosslinked copolymers etc. Such superabsorbents are usually supplied by such companies as Dow Chemical, Hoechst-Celanese, and Stoc hausen, Inc.

Placed between the separator 14 and the absorbent 16 is an elastic layer 56. The elastic layer 56 may consist of one or more sheets of a flexible closed cell polyethylene foam. The elastic layer 56 can have a thickness ranging from .5 millimeters to about 1.5 millimeters. A preferred thickness for the elastic layer 56 is about .8 millimeters. An example of a foam that can be used in the sanitary napkin is a Cell-Aire® CA-30 foam, having a thickness of about 0.79 millimeters, and a density of 1.2 pounds per cubic foot. This particular foam is available from Sealed Air Corporation having an address at 7110 Sante Fe Drive, Hodgkins, Illinois 60525. Another lightweight polypropylene foam which is suitable for this invention is MicroFoam® available from Ametek Microfoam Division, Brandwine Four Building, Route 1 and 202, Chadds Ford, Pennsylvania 19317.

The elastic layer 56 provides the sanitary napkin 10 with an elastic nature so that it is able to maintain its original dimensions and is also capable of returning to its original width after being squeezed or compressed while being worn by a woman. The elastic layer 56 is important since it allows the sanitary napkin 10 to skip back to approximately its original size even after the sanitary napkin 10 has been moistened by body fluid. This ability to return to its original size or at least close to its original dimensions reduces the time that the sanitary towel is in the strung, bulging or crooked phase. By retaining its original shape, the sanitary napkin 10 is less likely to experience the runoff of body fluid.

It should be noted that the adhesive construction can be used in the sanitary napkin 10 to join and hold the various layers together. For example, the adhesive construction can be used to attach the separator 14 to the elastic layer 56 and to attach the elastic layer 56 to the cover 12. The presence of such an adhesive and the amount that is used will depend on one's personal preference.

The sanitary napkin 10 also includes two elongated garment adhesive strips 56 and 60 which are secured to the bottom of the separator 14. The adhesive strips 58 and 60 are spaced apart and function to hold the sanitary napkin 10 to the crotch portion. inside of an undergarment during use. The garment adhesive 58 and 60 allows the sanitary napkin 10 to properly align and retain in relation to the vaginal opening of the wearer so that maximum fluid protection can be obtained.

It should be noted that the two garment adhesive strips 58 and 60 can be replaced with a single single strip if desired. Alternatively, a swirl pattern of adhesive or some other type of adhesive pattern can also be used. The garment adhesive is of such a nature that it will allow the wearer to remove the sanitary napkin 10 and reposition it on her undergarment if required. The garment adhesive is commercially available from National Starch and Chemical Company having an office located at 10 Finderne Avenue, Bridgewater, New Jersey 08807.

In order to protect the two garment adhesive strips 58 and 60 from contamination before use, the adhesive strips 58 and 60 are protected by a releasable peel paper 62. The peel paper 62 may be a white coated kraft paper on one side so that it can be released from a hot-melt adhesive. The peeling paper is designed to be removed by the wearer immediately before she holds the sanitary napkin 10 on the inside of her undergarment.

Referring again to Figure 3, one will note that this embodiment also uses an elastic layer 56, two separate spaced strips of garment adhesive 58 and 60, as well as a releasable peel paper 62. However, in this embodiment , the elastic layer 56 is placed below the separator 56 but is wrapped by the cover 34.

Referring now to Figures 4-7, four schematic alternatives are shown exhibiting different arrays for the multi-layer absorbent structure. In Figure 4, a multi-layer absorbent structure 64 is shown which includes a plurality of vertically stacked horizontal sheets 66 placed on top of at least one layer of tissue 68. Formed through the sheets 66 are thus minus three separate and distinct fluid conduits 70, 72 and 74. The fluid conduits 70, 72 and 74 are designed to allow rapid transport of fluid from the body downwardly from the cover and to the absorbent structure 64. The fluid conduit 72 is aligned perpendicular to the x axis and coaxially aligned with respect to the z axis. The fluid conduits 70 and 74 are offset from the x-axis in particular. Another way of saying this is that the fluid conduits 70 and 74 are aligned parallel but spaced from the z-axis.

All three fluid conduits 70, 72 and 74 communicate with the fluid conduits 76 formed between each pair of vertically stacked and horizontally aligned sheets 66 as well as with the fluid conduit 78 formed between the tissue sheet 68 and the further sheet. lower 66 of the multi-layer absorbent structure 64. The fluid conduits 76 are formed by the hollow space created between two sheets 66 which are placed side by side. The vertically oriented fluid conduits 70, 72 and 74 may be equally spaced and separated or they may be arranged at random. The conduits 70, 72 and 74 can also be formed at an angle of between 0 degrees to 180 degrees relative to the x axis if desired. Each fluid conduit 70, 72 and 74 can be of the same shape and size or can be of a different size and / or shape. Each fluid conduit 70, 72 and 74 may be an opening, a hole, a hole, a cut, a space, a partition, a gap, a tear, and so on. The fluid conduits 70, 72 and 74 do not necessarily have to be formed in each sheet 66 but instead can be formed in at least some of the sheets 66. It should be mentioned that each fluid conduit 70, 72 and 74 can be formed to a different depth in the multi-layer absorbent structure 64. However, for maximum performance, each fluid conduit 70, 72 and 74 should extend downward through the full thickness of the multi-layer absorbent structure 64.

The multi-layer absorbent structure 64 can be formed such that any point within the absorbent 64 is at a distance of less than about 2 millimeters from one of the fluid conduits 70, 72, 74, 76 and 78. This arrangement facilitates the fluid movement of the body deposited on the cover below in the absorbent 64.

Referring to Figure 5, a multi-layer absorbent structure 80 is shown having a triangular configuration about the z-axis. The multi-layer absorbent structure 80 is formed of a single sheet 82 of the absorbent material, such as a tissue sheet, which is bent into an accordion shape with a wide base which tapers to a narrower upper part. The multi-layer absorbent structure 80 contains a central fluid conduit 84 which extends downwardly from the top surface to the bottom base layer. The central fluid conduit communicates with the plurality of horizontally aligned fluid conduits 86 formed between the bent layer of the structure 80. This fluid conduit arrangement allows the body fluid deposited on the upper surface of the shell to flow rapidly towards down to the multi-layer absorbent structure 80. It should also be noted that the body fluid can flow down around the outer perimeter of the multi-layer absorbent structure 80 and still be directed to the horizontally oriented fluid conduits 86.

Figure 6 is another embodiment of a multi-layer absorbent structure 88 having a rectangular configuration relative to the z-axis. The multi-layer absorbent structure 88 includes a plurality of vertically stacked horizontal sheets 90 each having one or more slits or openings 92 formed therein. Preferably, each blade 90 has a plurality of cuts or openings 92 formed therein. The cuts or openings 92 can be spaced apart from each other and can be uniformly or randomly arranged on each sheet 90. The vertical orientation of each opening or slit 92 relative to the slits or openings 92 formed through an adjacent sheet 90 can to vary. Some slits or openings 92 may be aligned coaxially with the slits or openings 92 in an adjacent sheet 90 while the others are offset from each other. The slits or openings 92 serve as fluid conduits for routinely depositing body fluid on the cover to the entire surface area of the multi-layer absorbent structure 88. For good fluid distribution, the slits or openings 92 can be arranged so that any point within the absorbent structure 88 is at a distance of less than about 2 millimeters outside of one of the fluid conduits 92. Preferably, any point within the absorbent structure 88 is at a distance of less than about 1 millimeter out from one of the fluid conduits 92. When the slits or openings 92 are offset from each other in the two adjacent sheets 90, a rotate for tortuous fluid is presented which exposes a larger surface area of the absorbent structure of the fluid. multiple layers 88 within which body fluid can be absorbed and retained.

As stated above, each of the openings or slits 92 communicates fluidly with a plurality of horizontal conduits 94 formed between each pair of vertically stacked sheets 90. The vertical openings 92 communicate fluidly with the horizontal conduits 94. This arrangement of conduit it allows the body fluid to deposit on the upper surface of the cover to flow rapidly down to the multi-layer absorbent structure 88. It should also be noted that body fluid can flow down around the outer perimeter of the layer absorbent structure. 88 and still go inside the horizontal ducts 94.

Referring to Figure 7, yet another embodiment of the multi-layer absorbent structure 96 is shown having a triangular configuration relative to the z-axis. The multi-layer absorbent structure 96 includes a plurality of vertically stacked sheets 98 each having one or more slits or openings 100 formed therein. Preferably, each sheet 98 has one or more slits or openings 100 formed therein. the slits or openings 100 may be spaced from each other and may be uniformly or randomly arranged in each sheet 98. The vertical orientation of each slit or opening 100 relative to the slits or openings 100 formed through an adjacent sheet 98 may to vary. Some slits or openings 100 may be aligned coaxially with the slits or openings 100 in an adjacent sheet 98 while the others are offset from one another. When the slits or openings 100 are offset from each other in two adjacent sheets 98, a tortuous fluid path is presented which exposes a larger surface area of the multi-layer absorbent structure 96 into which it can be absorbed and retained. the fluid of the body.

As indicated above, each of the slits or openings 100 is fluidly communicated with a plurality of horizontal conduits 102 formed between each pair of vertically stacked sheets 98. The vertical openings 100 communicate fluidly with the horizontal conduits 102. This arrangement The conduit allows the body fluid deposited on the upper surface of the casing to flow rapidly down to the multi-layer absorbent structure 96.

It should be noted that the body fluid can flow down around the outer perimeter of the multi-layer absorbent structure 96 and go to the horizontal ducts 102.

When an absorbent article is constructed having a multi-layer absorbent structure as taught above it has been found that the absorbent article will work exceptionally well when it also has certain characteristics. These characteristics are given in Table 1 given below. The product labeled "S Code" in Table 1 represents the present invention. Three or more absorbent articles were tested to obtain the characteristics described above.

TABLE Note: "K-C" is an abbreviation for Kimberly-Clark Corporation.

"J &J" is an abbreviation for Johnson & Johnson.

"P &G" is an abbreviation for Procter & Gamble.

"Std Dev" is an abbreviation for standard deviation.

All absorbent articles to be tested for the characteristics identified above must be acclimated for at least two hours in a controlled environment at a temperature of 23 degrees Celsius ± 1 degree Celsius and a relative humidity of 50 ± 2 percent.

The first feature that the absorbent article should have is a "crush recovery" value of at least about 15 millimeters, preferably at least 18 millimeters and more preferably 20 millimeters or more. The "crush recovery" value is measured using an apparatus 104 shown in Figures 8 and 9. The apparatus 104 is designed to retain the absorbent article 106 having a pair of spaced apart longitudinal side edges 108 and 110. The absorbent article 106 also has an absorbent 107 with a pair of spaced apart longitudinal side edges 109 and 111. The side edges 109 and 111 may be coincident with not being spaced inward from the longitudinal side edges 108 and 110 of the absorbent article 106.

Referring to Figure 8, a tester 112 is shown which is capable of measuring the force in grams, required to crush the absorbent article 106 sideways. By sidewise it is meant along the axis and transverse center which is shown in Figure 1. The tester 112 includes the first and second arms, 114 and 116 respectively, only one of which has to be movable. The first and second arms 114 and 116 are coaxially aligned and spaced apart. The distance at which the arms 114 and 116 are separated can be varied to accommodate the size of the apparatus 104 and the size of the absorbent article 106 which is to be tested. The tester 102 is capable of moving at least one of the arms 114 and / or 116 relative to the other arm at a predetermined speed. A common tester which can be used is a Sintech® l / S which is available from Sintech, a division of MTS Systems Corp. having an office at 1400 Technology Drive, Eden Prairie, MN. 55344. A commercially available alternate tester is an Instron® tester apparatus available from Instron Corporation having an office at 100 Royall Street, Canton, MA 02021.

The apparatus 104 includes a first frame member 118 and a second frame member 120 which are in-between to operate in unison. The first frame member 118 and the second frame member 120 are. reciprocally movable one in relation to the other. Both of the frame members 118 and 120 respectively may be of rectangular configuration. Other forms can work equally well. The first frame member 118 has a first plate 122 with an inner surface 124 and an outer surface 126. The first frame member 113 also has a second plate 128 with an inner surface 130 and an outer surface 132. The first and second plates 122 and 128 respectively, are joined together by at least two support members 134 and 136, and preferably, by four support members.

In Figures 8 and 9, four support members are currently present but only two of the support members 134 and 136 respectively, are visible. The remaining two support members are located directly behind and at a distance from the two support members 134 and 136. When the four support members are present, these can be arranged in a rectangular shape so that each is connected to a corner of the support. the first and second plates 122 and 128 respectively.

Securing or formed on the inner surface 130 of the second plate 128 is a shoulder 138. The shoulder 138 may have an arched shape and more preferably a semicircular configuration having a radius of about 76 millimeters. The semicircular configuration of the shoulder 138 should have a smooth profile which makes contact with the central station of the edge of the longitudinal side 110 of the absorbent article 106. The shoulder 138 should have a fixed width depending on the thickness of the absorbent article 106. The width of the shoulder 138 is measured along a line extending perpendicular to the plane of the sheet illustrating Figure 8. The shoulder 138 should have a width of about 11 millimeters for an absorbent article which has a thickness or gauge varying from about from 2 millimeters to around 7 millimeters. The shoulder 138 should have a width of about 7 millimeters for an absorbent article which has a thickness or caliper of less than about 2 millimeters and a width or thickness of about 17 millimeters for an absorbent article having a thickness or gauge of more than about 7 millimeters. A method for measuring the thickness of an absorbent article 106 is described in an explicit detail later in this application.

Extending outwardly from shoulder 138 is at least one, preferably two and more preferably three or four rods or rods 140, 142 and 144. Each rod 140, 142 and 144 may be secured to shoulder 138 and / or second plate 128 by a common fastener, for example a pair of screws 146 as shown. Other fasteners, such as bolts, nuts, trims, pins, etc., can also be used as well as fastening by welding, fusion, adhesive, etc. These and other methods of securing or securing the rods 140, 142 and 144 to the shoulder 138 and / or the first plate 122 are well known to those skilled in the art.

The rods 140, 142 and 144 should be flexible members so as to be capable of bending outwardly as the absorbent article 106 becomes thicker as it is crushed along the y-axis. The rods 140, 142 and 144 can be constructed of a foldable or foldable material such as a plastic or rubber or these can be made of thin pieces of metal, wood etc. To measure the "crush recovery" value of a thin absorbent article, such as a sanitary napkin, each rod 140, 142 and 144 may be a thin plastic strip having a length of about 89 millimeters, a width of about 19 millimeters. millimeters and a thickness of about 1.6 millimeters. The exact dimension may vary to conform to a particular absorbent article. Each of the rods 140, 142 and 144 extends outward towards the first plate 122. The rods 140, 142 and 144 can be oriented parallel to each other and spaced apart so as not to interfere with each other. In Figures 8 and 9, the rods 140 and 144 are secured to one side of the shoulder 138 while the rod 142 is secured to the opposite side of the shoulder 138. This allows the rods 140, 142 and 144 to be offset from one another .

The second frame member 120 can be constructed to be very similar or identical in configuration to the first frame member 118 except that it will have a slightly different size to allow the two frame members 118 and 120 are interleaved. By "interlocked" it is meant that the first member of the material 118 is assembled in such a way with the second frame member 120 that one can move relative to the other being separated therefrom. The second frame member 120 has a third plate 148 with an inner surface 150 and an outer surface 152. The second frame member 120 also has a fourth plate 154 with an inner surface 156 and an outer surface 158. The third and fourth plates, 148 and 154 respectively are joined together by at least two support members 160 and 162, and preferably, by four support members. The fourth plate 154 is dimensioned and shaped so as to be able to slide between the first and second plates, 122 and 128 respectively, of the first frame member 118.

In Figures 8 and 9, four support members are present but only two support members 160 and 162 are visible. The remaining two support members are located directly behind the two support members 160 and 162. When the four support members are present, they can be arranged in a rectangular shape so that each is connected to a corner of the third plates and fourth, 148 and 154 respectively.

Secured to or formed on the inner surface 156 of the fourth plate 154 is a shoulder 164. The shoulder 164 may be arcuate in shape. More preferably, the shoulder 164 may have a semicircular configuration, and it must have a width identical to that described above for the shoulder 138. Extending outward from the shoulder 164 is the second frame member 120. This will cause the two shoulders 138 and 164 they approach each other and squeeze the longitudinal side edges 108 and 110 of the absorbent article 106 thereby crushing the article 106 at a preselected distance between the shoulders 138 and 164.

The method of operation of the apparatus 104 for crushing an absorbent article 106 sideways along the y-axis is as follows: first, the apparatus 104 is secured in the tester 112, preferably in a vertical orientation. When securing the first and second frame members, 118 and 120 respectively, of the apparatus 104 are attached to the two arms 114 and 116 of the tester 112. The first and second frame members 118 and 120, respectively, are set at a predetermined distance of separation, for example of about 102 millimeters. The placement of about 102 millimeters allows the absorbent article 106 to be placed between the first and second frame members 118 and 120 respectively, while they are in a flat or non-bulky condition. A pre-calibrated load cell, for example, a full-scale 50-pound compression / tension load cell is used.

Second, any wings, fin, panels, appendages or tapes that can be fastened to or integrally formed with the absorbent article 106 must be removed before the absorbent article 106 is tested. Such fins, wings, panels, appendages or projections can be removed before the test, by cutting them along a line approximately parallel to the longitudinal side edges 108 and 110 of the absorbent article 106. Third, the absorbent article 106 is moistened with 25 cc of 0.9 percent by weight of salt water. This can be done by pouring the salt water on the center of the side surface to the body of the absorbent article 106 at a sufficiently slow rate to allow all the salt water to be absorbed by the article 106. Fourth, the absorbent article moistened 106 is then centered on the apparatus 104 as indicated in Figure 8. Fifth, the load cell of the tester 112 is zeroed according to the manufacturer's instructions. Sixth, the tester is then caused to cause arms 114 and 116 to separate at a predetermined rate. The current "crush recovery" values listed in Table 1 were obtained at a rate of 304.8 mm / minute. This action causes the longitudinal side edges 108 and 110 of the absorbent article 106 to collapse towards each other between the shoulders 138 and 164. The tester 112 will measure and record the load exerted on the absorbent article 106 as it is crushed. The tester 112 must be programmed to stop when the first and second frame members 118 and 120 respectively are set at a distance of eg 38 millimeters, see Figure 9 when a sanitary napkin is tested. The maximum force applied during the test is measured and recorded. This is the "wet load" value which will be discussed below.

After the absorbent article 106 has been crushed, the arms 114 and 116 of the tester 112 are retracted to their position prior to the original test. In this position, the longitudinal side edge 110 of the absorbent article 106 is in contact with the first shoulder 138 and the opposite longitudinal side edge 108 is spaced from the second shoulder 164. This arrangement allows the absorbent article 106 to recover freely towards its original transverse dimension . After approximately 30 seconds, the recovered width is measured er. millimeters The recovered width is the distance between the longitudinal side edges 109 and 110 of the absorbent 107. The "crush recovery value" is this recovered width measured minus the distance at which the absorbent article 106 was crushed, for example about 38 millimeters for the samples recorded in Table 1. There will be a "crush recovery" value for each absorbent article 106 tested.

The maximum load, measured in grams, during the test identified above is mentioned as the wet load value. A second feature that the absorbent article 106 should exhibit is a high wet load value. The wet load is a measure of the ability of an absorbent article to resist deformation after it has absorbed a given amount of fluid. Many thin absorbent articles exhibit a tendency to bulge, twist or string after they absorb a certain amount of body fluid. Such configurations create a high likelihood that the absorbent article will squeeze out by contacting the additional body fluid with the body-side cover. By constructing an absorbent article with a predetermined "wet load" value, one can minimize the tendency of the article to bulge, twist or string. The absorbent article 106 should have a "wet load" value of at least about 300 grams, preferably at least 320 grams, and more preferably at least 350 grams or more.

A third feature of the absorbent article is that it should have a thickness or caliper of less than about 5 millimeters, preferably from between about 3 millimeters to 5 millimeters, and more preferably from about 4 millimeters to about 5 mm. The thickness is measured by placing a block of lucite, measuring 12.7 millimeters by 44.5 millimeters on top of the absorbent article 106. The thickness is determined with an indicator meter that measures the distance of the block above a flat surface. The block is placed with one of the edges of about 44.5 millimeters long along the long edges of the absorbent core 107 of the absorbent article 106 with the entire block itself being on top of the absorbent core 107. The block is centered approximately along the length of the absorbent article 106. The height of the absorbent article 106 plus the block, is then subtracted from the height of the block only on the surface, to give the thickness of the absorbent article 106.

A fourth characteristic of the absorbent article is that it must exhibit a low "stress value". The stress value of an absorbent article is defined as the dry load divided by the thickness. The dry charge is obtained by running a test identical to that described above for the wet load except that the absorbent article 106 is not moistened with salt water. The smaller the tension value, the more comfortable the absorbent article will be in use. The absorbent article must have a tensile value of less than about 100 grams / millimeter, preferably less than about 90 grams / millimeter, and more preferably less than about 85 grams / millimeter.

A fifth characteristic of the absorbent article 106 is that it must have an absorbent capacity of at least 20 grams, preferably above about 25 grams, and more preferably, about 27 grams. The absorbent capacity of an absorbent article is measured as if: the absorbent article is allowed to saturate in an excess of 0.9 percent by weight of salt water for 5 minutes. Then it is placed face down on the grid of a vacuum box, and it will be covered with a rubber mat to make a vacuum seal. A vacuum of 0.5 psi is pulled through the grid for approximately 5 minutes to extract excess salt water from the absorbent article. The amount of salt water remaining in the absorbent article after vacuum extraction is the measured absorbent capacity.

Although the invention has been described in conjunction with a specific embodiment it will be understood that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Therefore, this invention is intended to encompass all those alternatives, modifications and variations which fall within the spirit and scope of the appended claims.

Claims (61)

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

1. An apparatus comprising: a) a tester having the first and second arms, at least one of which is movable, said arms are capable of causing a controlled movement at a predetermined speed of a device clamped therebetween and means for measuring the force required for said movement; controlled movement; b) a first frame member attached at one end to said first arm, said first frame member having a shoulder with a first rod extending outwardly therefrom; Y c) a second frame member attached at one end to said second arm, said second frame member having a shoulder with a second rod extending outwardly therefrom, said first and second frame members being interlocked so that said first bars and second are spaced apart to allow an absorbent article to be placed therebetween, and movement of the first frame member relative to the second frame member causes said absorbent article to be squashed in a sideways direction between said shoulders.

2. The apparatus as claimed in clause 1 characterized in that said first frame member has an outwardly extending shaft which can be releasably attached to said first arm and said second frame member has an axis extending outwardly which can be releasably attached to said second arm.

3. The apparatus as claimed in clause 1 characterized in that said first and second rods are flexible.

4. The apparatus as claimed in clause 1 characterized in that said first and second rods are made of plastic.

5. The apparatus as claimed in clause 1 characterized in that said first and second rods are aligned in parallel to each other.

6. The apparatus as claimed in clause 1 characterized in that said first and second rods are offset from each other.

7. The apparatus as claimed in clause 1 characterized in that said first frame member has an arcuately shaped shoulder with at least two rods extending outwardly therefrom.

8. The apparatus as claimed in clause 1 characterized in that said second frame member has an arcuately shaped shoulder with at least rods extending outwardly therefrom.

9. The apparatus as claimed in clause 1 characterized in that said first and second frame members are reciprocally movable relative to each other.

10. An apparatus comprising: a) a tester having the first and second arms, which are aligned coaxially and spaced apart, at least one of said arms being movable, said arms being capable of causing a controlled movement at a predetermined speed of a device clamped between them and means for measuring the force required for said controlled movement; b) a first rectangular frame member attached at one end to said first arm, said first frame member having a shoulder with a first flexible rod extending outwardly therefrom; and c) a second rectangular frame member attached at one end to the second arm, said second frame member having a shoulder with a second flexible rod extending outwardly therefrom, said first and second frame members being interlocked so that said first and second rods are spaced apart to allow an absorbent article to be placed therebetween, and the movement of said first frame member relative to the second frame member causes an absorbent article to be crushed in the direction toward the ends. sides between said shoulders.

11. The apparatus as claimed in clause 10 characterized in that said first frame member has an outwardly extending shaft which can be releasably attached to said first arm and said second frame member has an axis extending outwardly which can be releasably attached to said second arm.

12. The apparatus as claimed in clause 10 characterized in that said first frame member has an arcuately shaped shoulder with at least two rods extending outwardly therefrom.

13. The apparatus as claimed in clause 10 characterized in that said second frame member has an arcuately shaped shoulder with at least two rods extending outwardly therefrom.

14. The apparatus as claimed in clause 10 characterized in that said first and second frame members are reciprocally movable relative to one another.

15. An apparatus comprising: a) a first frame member having the first and second spaced apart plates secured together by at least two support members, each plate having an inner surface and an outer surface, a first rod extending outwardly from said second plate, and a mechanism of attachment secured to said outer surface of said first plate for connection to the tester; Y b) a second frame member having the third and fourth spaced apart plates secured together by at least two support members, each plate having an inner surface and an outer surface, and a second rod extending outwardly from said fourth plate, said second frame member is dimensioned to allow said fourth plate to slide between the first and second plates of said first frame member so that an absorbent article placed between said first and second rods can be crushed to a predetermined dimension, and a clamped mechanism secured to said outer surface of said third plate for connection to said tester so that said first and second frame members can move axially relative to one another.

16. The apparatus as claimed in clause 15 characterized in that said first frame member has a rectangular configuration.

17. The apparatus as claimed in clause 15 characterized in that said second frame member has a rectangular configuration.

18. The apparatus as claimed in clause 15 characterized in that said first frame member includes four support members.

19. The apparatus as claimed in clause 15 characterized in that said second frame member includes four support members.

20. The apparatus as claimed in clause 15 characterized in that said first frame member has three rods attached thereto and said second frame member has three rods attached thereto, said rods intermeshing to form an area between the second plates and fourth in which an absorbent article can be placed.

21. An absorbent article comprising: a) a cover permeable to liquid; b) a separator impermeable to liquid; Y c) an absorbent placed between said cover and said separator, and said article having a crush recovery value of at least 15 millimeters, a wet load value of at least about 300 grams, a tension value of less than about 100 grams / millimeter and a thickness of less than about 5 millimeters.

22. The absorbent article as claimed in clause 21 characterized in that it has a wet load greater than about 365 grams.

23. The absorbent article as claimed in clause 21 characterized in that it has an absorbent capacity of at least 20 grams.

24. The absorbent article as claimed in clause 21 characterized in that said tension value is less than about 90 grams / millimeter.

25. An absorbent article comprising: a) a separator impermeable to liquid; Y b) an absorbent secured to said separator, and said article has a crush recovery value of at least about 15 millimeters, a wet load value of at least 300 grams, a stress value of less than about of 100 grams / millimeter, and a thickness of less than about 5 millimeters.

26. The absorbent article as claimed in clause 25 characterized in that said absorbent is constructed of a multi-layer thin pored fabric.

27. The absorbent article as claimed in clause 26 characterized in that said multi-layer absorbent is formed of a single sheet bent over itself.

28. The absorbent article as claimed in clause 25 characterized in that said multi-layer absorbent includes a plurality of individual sheets.

29. The absorbent article as claimed in clause 26 characterized in that it has a central longitudinal axis and said absorbent has at least one conduit formed therein which is aligned perpendicularly with said axis.

30. An absorbent article comprising: a) a cover permeable to liquid; b) a separator impermeable to liquid; Y c) an absorbent placed between said cover and said separator, and said article has an absorbent capacity of at least 20 grams, crush recovery value of at least about 15 millimeters, a wet load value of at least less than about 300 grams, a tension value of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeters.

31. The absorbent article as claimed in clause 30 characterized in that said absorbent is constructed of a multi-layer fine pored fabric.

32. The absorbent article as claimed in clause 30 characterized in that said absorbent has a wet load value of more than about 320 grams.

33. The absorbent article as claimed in clause 32 characterized in that said absorbent has a wet load value ranging from about 320 grams to about 425 grams.

34. The absorbent article as claimed in clause 30 characterized in that said absorbent has a wet load value of more than about 365 grams.

35. The absorbent article as claimed in clause 30 characterized in that said cover is a perforated thermoplastic film.

36. An absorbent article comprising: a) a cover permeable to liquid; b) a separator impermeable to liquid; Y c) an absorbent placed between said cover and said separator, said absorbent is constructed of a multi-layer material having the ducts formed therein so that any point within said absorbent is at a distance of about 2 millimeters outward from one of said ducts, said ducts facilitate the movement of body fluid deposited on said cover down to said absorbent, and said article has a crush recovery value of at least about 15 millimeters, a wet load value of at least less than about 300 grams, a tension value of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeters.

37. The absorbent article as claimed in clause 36 characterized in that said cover is a composite including a perforated thermoplastic film bonded to a spunbonded material.

38. The absorbent article as claimed in clause 36 characterized in that it has a central longitudinal axis and one of said conduits is aligned perpendicularly with said axis.

39. The absorbent article as claimed in clause 36 characterized in that it has a central longitudinal axis and one of said conduits is offset from said axis.

40. The absorbent article as claimed in clause 36 characterized in that said multi-layer absorbent is formed of at least one sheet bent in an accordion shape on itself.

41. The absorbent article as claimed in clause 36 characterized in that said multi-layer absorbent includes a plurality of sheets vertically stacked.

42. An absorbent article having a longitudinal central axis, said article comprises: a) a cover permeable to liquid; b) a separator impermeable to liquid; c) a transfer layer placed between said cover and said separator, said transfer layer having a plurality of perforations formed therein; d) an absorber positioned between said transfer layer and said separator; Y e) an elastic layer placed between said absorbent and said separator, said article having a crush recovery value of at least about 15 mm, a wet load value of at least about 300 grams, a tension value of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeters.

43. The absorbent article as claimed in clause 42 characterized in that said absorbent is constructed of at least one sheet of fabric which is folded into an accordion shape to obtain a multi-layer structure having a conduit formed therein, said conduit it extends through at least a portion of said multi-layered structure and is aligned perpendicularly with said central longitudinal axis.

44. The absorbent article as claimed in clause 42 characterized in that said multi-layer absorbent has the ducts formed therein so that any point within said absorbent is at a distance of less than about 2 millimeters from one of said ducts, said ducts facilitate the movement of body fluid deposited on said cover downwardly inside said absorbent.

45. The absorbent article as claimed in clause 44 characterized in that said multi-layer absorbent includes a plurality of sheets stacked vertically.

46. The absorbent article as claimed in clause 45 characterized in that between each pair of sheets stacked vertically is a conduit.

47. The absorbent article as claimed in clause 44 characterized in that said conduits are spaces formed in at least some of said sheets.

48. The absorbent article as claimed in clause 44 characterized in that said conduits are divisions formed in at least some of said sheets.

49. The absorbent article as claimed in clause 44 characterized in that said conduits are formed by bending said multilayer structure.

50. An absorbent article characterized in that it has a longitudinal central axis, said article comprises: a) a cover permeable to liquid; b) a separator impermeable to liquid; c) a transfer layer placed between said cover and said separator, said transfer layer having a plurality of openings formed therein; d) an absorbent placed between said transfer layer and said separator, said absorbent being constructed of a multi-layer material having the ducts formed therein; Y e) an elastic layer placed between said absorbent and said separator, said article having a crush recovery value of at least about 15 mm, a wet load value of at least about 300 grams, a value of tension of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeters.

51. The absorbent article as claimed in clause 50 characterized in that said multi-layer absorbent contains from 50 to 30 sheets.

52. The absorbent article as claimed in clause 50 characterized in that said absorbent is devoid of superabsorbent.

53. The absorbent article as claimed in clause 50 characterized in that said absorbent is a wet-dried air-dried tissue.

54. The absorbent article as claimed in clause 50 characterized in that said absorbent is a meltblown olefin fabric.

55. The absorbent article as claimed in clause 54 characterized in that said meltblown olefin fabric has a hydrophilic surface.

56. The absorbent article as claimed in clause 50 characterized in that said transfer layer is spun-bonded.

57. The absorbent article as claimed in clause 50 characterized in that said openings formed in said transfer layer are arranged randomly.

58. The absorbent article as claimed in clause 50 characterized in that at least one of said perforations formed in said cover has a diameter of at least 0.3 millimeters and each of said perforations are spaced from an adjacent opening at least by 0.3 mm.

59. The absorbent article as claimed in clause 50 characterized in that a majority of said openings formed in said cover have a diameter greater than about 0.3 millimeters.

60. The absorbent article as claimed in clause 50 characterized in that a majority of said openings formed in said transfer layer are spaced apart from each other by at least 0.3 millimeters.

61. The absorbent article as claimed in clause 50 characterized in that said elastic layer is a closed cell polyethylene foam. SUMMARY An apparatus for measuring the recovery of crushing of an absorbent article as well as the article itself is described. The apparatus includes a tester having the first and second arms, at least one of which is movable. The apparatus also includes a first frame member attached at one end to the first arm of the tester. The first frame member has a shoulder with a first rod extending outwardly therefrom. The apparatus further includes a second frame member attached at one end to the second arm of the tester. The second frame member has a shoulder with a second rod extending outwardly therefrom. The first and second frame members are interleaved so that the first and second rods are spaced apart to allow the absorbent article to be placed therebetween. In addition, the first frame member relative to the second frame member causes the absorbent article to be squeezed in a sideways direction between the shoulders. By reversing the relative movement of the frame members, the absorbent article is able to expand outward to its original transverse dimension. The amount of recovery to the sides is measured as the value of "recovery from crushing". The absorbent article includes a liquid permeable cover, a liquid impervious separator and an absorbent placed between the cover and the separator. The absorbent article has a crush recovery value of at least about 15 millimeters, a wet load value of at least about 300 grams, a tension value of less than about 100 grams / millimeter, and a thickness of less than about 5 millimeters.