HK1088206A - Simple disposable absorbent article - Google Patents

Description

Simple disposable absorbent article

Technical Field

The present invention relates to disposable absorbent articles such as disposable diapers and other articles intended for use on incontinent persons.

Background

Disposable absorbent articles are designed to absorb and contain bodily waste in order to prevent soiling of the body and clothing of the wearer, as well as bedding or other objects with which the wearer comes into contact.

As the range of use of disposable absorbent articles has expanded, their complexity has increased by the incorporation of additional components that serve to enhance their performance and appearance. As complexity increases, the cost of materials and the cost of manufacturing processes also increase. As a result, the sales prices of these articles have risen to levels that many potential purchasers around the world cannot afford to pay. Therefore, there is a need for a simple disposable absorbent article.

Disclosure of Invention

The present invention provides a simple disposable absorbent article including a chassis and an absorbent assembly. The chassis includes a water-impermeable sheet that is folded laterally inward at both of its side edges to form opposing side flaps. Each side flap is attached to the interior surface of the chassis adjacent to its end edges. Each side flap has a longitudinally extending elastic gathering member attached adjacent to its proximal edge. The absorbent assembly has a width and a length less than the chassis. The side edges and end edges of the absorbent assembly may be disposed adjacent to the respective side edges and end edges of the chassis. The absorbent assembly includes an absorbent core. The absorbent core may comprise superabsorbent particles and these particles may be enclosed within pockets. The chassis may comprise an extensible formed web material. The absorbent assembly may be attached in a cruciform pattern to the chassis to allow portions of the chassis to extend laterally.

Drawings

In the drawings, like reference numerals designate like elements, which may be the same or different in the several exemplary embodiments. Some of the figures may be simplified by the omission of selected elements for the purpose of more clearly showing other elements. Such omissions of elements in some figures are not necessarily indicative of the presence or absence of particular elements in any of the exemplary embodiments, except as may be explicitly delineated in the corresponding written description.

FIG. 1 is a plan view of an exemplary disposable absorbent article in the form of a diaper 20, which is shown in its flat, uncontracted state, i.e., without the contraction induced by elastic members. In FIG. 1, the interior portion of the diaper 20 that faces inwardly toward the wearer and contacts the wearer is shown facing the viewer.

FIG. 2 is a plan view of the diaper 20 of FIG. 1 in its flat, uncontracted state, with the exterior portion of the diaper 20 that faces outwardly away from the wearer shown facing the viewer.

Figure 3 is a section view of the diaper 20 of figure 1 taken at the section line 3-3.

Figure 4 is a section view of the diaper 20 of figure 1 taken at the section line 4-4.

Figure 5 is a section view of the diaper 20 of figure 1 taken at the section line 5-5.

Figure 6 is a section view of the diaper 20 of figure 1 taken at the section line 6-6.

FIG. 7 is a simplified side elevation view of an exemplary diaper 20 being worn about a lower torso of a wearer.

FIG. 8 is a front elevation view of the diaper 20 of FIG. 7 being worn about the lower torso of the wearer.

FIG. 9 is a back elevation view of the diaper 20 of FIG. 7 being worn about the lower torso of a wearer.

Figure 10 is a plan view of an exemplary diaper 20 shown in its flat, uncontracted state (i.e., without the contraction induced by elastic members) before the side flaps 147a and 147b are formed by folding portions of the chassis 100 laterally inward, i.e., toward the longitudinal axis 42. In figure 10, the interior portion of the diaper 20 that faces inwardly toward the wearer and contacts the wearer is shown facing the viewer.

FIG. 11 is a plan view of the diaper 20 of FIG. 10 in its flat, uncontracted state, with the exterior portion of the diaper 20 that faces outwardly away from the wearer shown facing the wearer.

Figure 12 is a section view of the diaper 20 of figure 10 taken at the section line 12-12.

Figure 13 is a section view of the diaper 20 of figure 10 taken at the section line 13-13.

Figure 14 is a section view of the diaper 20 of figure 10 taken at the section line 14-14.

Figure 15 is a section view of the diaper 20 of figure 10 taken at the section line 15-15.

FIG. 16 is a perspective view of an exemplary diaper 20 shown in its flat, uncontracted state, i.e., without the contraction induced by elastic members, in FIG. 16, with the interior portion of the diaper 20 that faces inwardly toward the wearer and contacts the wearer shown facing upward.

Figure 17 is a plan view of an exemplary diaper 20 shown in its flat, uncontracted state, i.e., without the contraction induced by elastic members, in which portions of the chassis remain laid out flat when other portions of the chassis are folded laterally inward to form the side flaps 147a and 147 b.

Figure 18 is a plan view of an exemplary diaper 20 shown in its flat, uncontracted state, i.e., without the contraction induced by elastic members, in which the chassis sections are folded over and attached to the interior surface of the absorbent assembly to impart an hourglass shape to the diaper 20.

FIG. 19 is a section view of the diaper 20 of FIG. 18 taken at the section line 19-19.

FIG. 20 is a plan view of an exemplary fragment of a formed web material.

FIG. 21 is a simplified plan view of an exemplary disposable absorbent article in the form of a diaper 20 having adhesive tape tabs 114a and 114b and a fastening surface 116 attached to the chassis in a flat, uncontracted state, i.e., without the contraction induced by elastic members. In figure 21, the interior portion of the diaper 20 that faces inwardly toward the wearer and contacts the wearer is shown facing the viewer.

FIG. 22 is a simplified plan view of the diaper 20 of FIG. 21 in its flat, uncontracted state, with the exterior portion of the diaper 20 that faces outwardly away from the wearer shown facing the viewer.

FIG. 23 is a simplified left side elevation view of an exemplary diaper 20 including cohesive fastening sheets being worn about the lower torso of a wearer.

FIG. 24 is a simplified right side elevation view of the diaper 20 of FIG. 23 including cohesive fastening sheets being worn about the lower torso of the wearer.

FIG. 25 is a plan view of an exemplary diaper 20 shown in its flat, uncontracted state, i.e., without the contraction induced by elastic members, in which alternative versions of cohesive fastening sheets are shown incorporated. In figure 25, the interior portion of the diaper 20 that faces inwardly toward the viewer and contacts the wearer is shown facing the viewer.

FIG. 26 is a plan view of the diaper 20 of FIG. 25 in its flat, uncontracted state, with the exterior portion of the diaper 20 that faces outwardly away from the wearer shown facing the viewer.

FIG. 27 is a section view of the diaper 20 of FIG. 25 taken at the section line 27-27.

FIG. 28 is a section view of the diaper 20 of FIG. 25 taken at the section line 28-28.

FIG. 29 is a plan view of an exemplary absorbent assembly 200. FIG. 29 shows the absorbent assembly 200 separated from its attached chassis 100 in an exemplary diaper 20 and the interior portion of the absorbent assembly 200 that faces inwardly toward the wearer and contacts the wearer is shown facing the viewer.

Figure 30 is a section view of the absorbent assembly 200 of figure 29 taken at the section line 30-30.

Figure 31 is a section view of the absorbent assembly 200 of figure 29 taken at the section line 31-31.

FIG. 32 is a section view of an exemplary absorbent assembly 200 showing details of an exemplary absorbent core.

Detailed Description

Definition of

In the present specification, the following terms have the following meanings:

the term "absorbent article" refers to a device that absorbs and contains liquid, and more specifically, refers to a device that is placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body.

The term "diaper" refers to an absorbent article that is generally worn by infants and incontinent persons about the lower torso so as to encircle the waist and the legs of the wearer and that is specifically adapted to receive and contain urinary and fecal waste.

The term "disposable" is used to refer to the nature of absorbent articles that generally are not intended to be laundered or otherwise restored or reused as an absorbent article, i.e., they are intended to be discarded after a single use and, preferably, to be recycled, composted or otherwise disposed of in an environmentally compatible manner.

The term "longitudinal" refers to a direction running from one waist edge to the opposite waist edge of the article and generally parallel to the maximum linear dimension of the article. Directions within 45 of the longitudinal direction are considered to be "longitudinal".

The term "transverse" refers to a direction running from one side edge to the opposite side edge of the article and generally at right angles to the longitudinal direction. Directions within 45 of the lateral direction are considered to be "lateral".

The term "disposed" means an element that is attached and positioned in a particular place or position to form a unitary structure with other elements.

The term "attached" refers to elements being joined or combined by fastening, adhering, bonding, etc. by any method suitable for the elements being attached together and their constituent materials. Many suitable methods of joining elements together are well known, including adhesive bonding, pressure bonding, thermal bonding, mechanical attachment, and the like. Such attachment methods may be used to attach elements together over a particular area, either continuously or intermittently.

The term "tack" refers to the property of a material to stick to itself, but not to any significant extent to other materials.

The terms "water-permeable" and "water-impermeable" refer to the penetrability of materials in the context of the intended use of disposable absorbent articles. In particular, the term "water-permeable" refers to a layer or a layered structure having pores, openings, and/or interconnected void spaces that permit liquid water to pass through its thickness in the absence of a forcing pressure. Conversely, the term "water-impermeable" refers to a layer or a layered structure through the thickness of which liquid water cannot pass in the absence of a forcing pressure. A layer or a layered structure that is water-impermeable according to this definition may be permeable to water vapor, i.e., may be "vapor-permeable". As is well known in the art, a common method of measuring the permeability to water of the materials typically used in absorbent articles is a hydrostatic pressure test, also known as a hydrostatic head test or simply a "hydrohead" test. INDA (formerly International Nonwovens And Disposities Association, now known as The Association of The Nonwoven fabrics industry) And EDANA (European Disposities And Nonwovens Association) have validated suitable, well-known legal methods for head testing.

The terms "proximal" and "distal" refer respectively to the location of an element near or far from the center of a structure, e.g., the proximal edge of a longitudinally extending element is located closer to the longitudinal axis than the distal edge of the same element is located relative to the same longitudinal axis.

Description of exemplary diaper embodiments

As shown in figure 1, figure 2, figure 3, figure 4, figure 5, and figure 6, an end portion of the exemplary diaper 20 is configured as a front waist region 36. The longitudinally opposing end portions of the diaper 20 are configured as a back waist region 38. An intermediate portion of the diaper 20 extending longitudinally between the front waist region 36 and the back waist region 38 is configured as a crotch region 37.

The basic structure of the diaper 20 includes a chassis 100. The chassis 100 has a laterally extending front waist edge 136 in the front waist region 36 and a longitudinally opposing and laterally extending waist edge 138 in the back waist region 38. The chassis 100 has a longitudinally extending left side edge 137a and a laterally opposing and longitudinally extending right side edge 137b, both chassis side edges extending longitudinally between the front waist edge 136 and the back waist edge 138. The chassis 100 has an interior surface 102 and an exterior surface 104. The chassis 100 also has a longitudinal axis 42 and a lateral axis 44. The longitudinal axis 42 extends through the midpoint of the front waist edge 136 and the midpoint of the back waist edge 138 of the chassis 100. The lateral axis 44 extends through the midpoint of the left side edge 137a and the midpoint of the right side edge 137b of the chassis 100. The exemplary chassis 100 shown in figure 1 also has longitudinally extending and laterally opposing side flaps 147a and 147b that are described in more detail below.

The basic structure of the diaper 20 includes an absorbent assembly 200 attached to the chassis 100. The absorbent assembly 200 has a laterally extending front edge 236 in the front waist region 36 and a longitudinally opposing and laterally extending back edge 238 in the back waist region 38. The absorbent assembly 200 has a longitudinally extending left side edge 237a and a laterally opposing and longitudinally extending right side edge 237b, both absorbent assembly side edges extending longitudinally between the front edge 236 and the back edge 238. The absorbent assembly 200 has an interior surface 202 and an exterior surface 204. The absorbent assembly 200 may be disposed symmetrically with respect to the longitudinal axis 42 and the lateral axis 44. Alternatively, the absorbent assembly 200 may be disposed asymmetrically with respect to either or both of the longitudinal axis 42 and the lateral axis 44. For example, the absorbent assembly 200 shown in figure 1 is disposed symmetrically with respect to the longitudinal axis 42 and asymmetrically with respect to the lateral axis 44. In particular, the absorbent assembly 200 shown in figure 1 is disposed asymmetrically toward the front waist region 36.

The respective front edge 236, back edge 238, left side edge 237a, and right side edge 237b of the absorbent assembly 200 may lie inward of the respective front waist edge 136, back waist edge 138, left side edge 137a, and right side edge 137b of the chassis 100, as in the exemplary diaper 20 shown in figure 1. Such a configuration in which one or more of the edges of the absorbent assembly 200 lies inward of the corresponding edges of the chassis 100 may be desirable, for example, in order to allow the relatively more flexible layer or layers adjacent to the edges of the chassis to conform to the body of the wearer and thereby form effective gasket-like seals against the skin of the wearer without being constrained by a thick and inflexible absorbent assembly. Alternatively, one or more of the edges of the absorbent assembly 200 may coincide with the corresponding edge or edges of the chassis 100.

As shown in figure 7, figure 8, and figure 9, when the diaper 20 is worn on the lower torso of a wearer, the front waist edge 136 and the back waist edge 138 encircle the waist of the wearer, while the chassis side edges 137a and 137b encircle the legs of the wearer. Meanwhile, the crotch region 37 is generally positioned between the legs of the wearer, and the absorbent assembly 200 extends from the front waist region 36 through the crotch region 37 to the back waist region 38.

Description of the base

In figure 10, figure 11, figure 12, figure 13, figure 14, and figure 15, the exemplary chassis 100 is shown laid out flat before the side flaps 147a and 147b are formed by folding portions of the chassis 100 laterally inward, i.e., toward the longitudinal axis 42, to form the two respective side flaps 147a and 147b and the side edges 137a and 137b of the chassis 100 as shown in figure 1, figure 2, figure 3, figure 4, figure 5, and figure 6. In this laid out flat condition, the chassis 100 has a longitudinally extending left outer side edge 155a and a laterally opposing and longitudinally extending right outer side edge 155 b. Two chassis outer side edges extend longitudinally between the front waist edge 136 and the back waist edge 138. As described in more detail below, when the side flaps 147a and 147b are formed by folding portions of the chassis 100 laterally inward, the outer side edges 155a and 155b of the chassis form the respective proximal edges 157a and 157b of the side flaps.

The chassis 100 includes a water-impermeable backsheet 26. The backsheet 26 forms an outer surface that is intended to be placed toward any garment in which the diaper 20 is worn. Many suitable materials for use as the backsheet 26 are well known and include films of polypropylene and other polyolefins. Multi-layer backsheets, such as laminates of films and nonwovens, are also well known and may be suitable for use as the backsheet 26. Such a laminate backsheet may have the nonwoven disposed exteriorly, providing a more cloth-like outermost layer in feel and appearance than if a film were used as the outermost layer.

The chassis 100 may, but need not, additionally include an inner liner 22 joined to the backsheet 26. The inner liner 22 may form a portion of the interior surface 102 of the chassis 100 that is intended to be placed against the body of a wearer. The inner liner 22 is preferably made of a soft material that will not irritate the skin of the wearer. Such an inner liner 22 desirably functions to isolate the skin of the wearer from a portion of the backsheet 26, such as when the diaper 20 is worn under conditions in which contact between the skin and a backsheet film could be uncomfortable. Many suitable materials for the inner liner 22 are well known in the art, including rayon and synthetic nonwovens such as spunbonded or carded polypropylene or polyester. The inner liner 22 may extend to the same width and length as the backsheet 26. For example, in the exemplary chassis 100 shown in figures 10 and 11, the edges of the inner liner 22 are not separately identified because the inner liner 22 has the same extent as the backsheet 26.

Alternatively, one or more of the edges of the inner liner 22 may lie inward of the edges of the backsheet 26. For example, in accordance with the exemplary diaper 20 shown in figure 1, only the portion of the inner liner 22 located in the gap between the front edge 236 of the absorbent assembly 200 and the front waist edge 136 of the chassis 100 and between the back edge 238 of the absorbent assembly 200 and the back waist edge 138 of the chassis 100 is exposed, while the remainder of the inner liner 22 is covered by the absorbent assembly 200 and the side flaps 147a and 147 b. Therefore, a laterally extending strip of the inner liner 22 disposed in the gap in the front waist region 36 and a similar laterally extending strip of the inner liner 22 disposed in the gap in the back waist region 38 may suffice to isolate the skin of the wearer from the backsheet 26 in these two gaps.

As shown in figure 1, figure 2, figure 3, figure 4, figure 5, and figure 6, the exemplary chassis 100 has longitudinally extending and laterally opposing side flaps 147a and 147b that are disposed on the interior portion of the diaper 20 that faces inwardly toward the wearer and contacts the wearer. The side flaps 147a and 147b may be formed by folding portions of the chassis 100 laterally inward, i.e., toward the longitudinal axis 42, to form the respective side flaps 147a and 147b and side edges 137a and 137b of the chassis 100. Alternatively, the side flaps 147a and 147b may be formed by attaching an additional layer or layers to the chassis 100 at or adjacent to each of the respective side edges 137a and 137b of the chassis 100. In embodiments in which the side flaps are formed by attaching an additional layer or layers to the chassis, each additional layer may be attached at or adjacent to its laterally distal edge.

The portions of the film backsheet 26 that are folded laterally inward to form the side flaps may contact the wearer's skin during use of the diaper 20. However, in order to make the film backsheet extensible, which has been deformed to form alternating ridges and valleys, the ridges and valleys in such a film backsheet may provide air-permeable channels, mitigating any concern about such contact of the film backsheet with the skin.

In embodiments in which portions of the chassis 100 are folded laterally inward to form the side flaps 147a and 147b, the chassis 100 may simply be folded loosely or may be creased along a portion of each of its side edges 137a and 137 b. For example, it may be desirable to form creases along portions of the side edges 137a and 137b in the crotch region 37 in order to impart a more finished appearance to the diaper 20. Alternatively or in addition to creasing, a portion of each of the folded side flaps 147a and 147b adjacent to the side edges 137a and 137b may be attached to the interior surface 102 of the chassis 100 to achieve a similar result.

The left side flap 147a has a proximal edge 157a and the right side flap 147b has a proximal edge 157 b. In the exemplary diaper 20 shown in figure 1, the left side flap 147a and the right side flap 147b overlap the absorbent assembly 200, i.e., the proximal edge 157a and the proximal edge 157b lie laterally inward of the respective left side edge 237a and right side edge 237b of the absorbent assembly 200. Such an overlapped configuration may be desirable in order to impart a more finished appearance to the diaper 20 than if it were a non-overlapped configuration. Alternatively, the left side flap 147a and the right side flap 147b may not overlap the absorbent assembly 200, i.e., the proximal edge 157a and the proximal edge 157b may be located laterally outward of the respective left side edge 237a and right side edge 237b of the absorbent assembly 200.

In the exemplary chassis 100 shown in figure 1, the left side flap 147a and the right side flap 147b extend the full length of the chassis 100 between the front waist edge 136 and the back waist edge 138. Such a full length configuration may be desirable in order to minimize the amount of waste material and the difficulties associated with the manufacture of the diaper 20, particularly when the method used to manufacture the diaper 20 requires the use of the material for the chassis 100 in the form of a continuous web or multiple continuous webs. Alternatively, the side flaps may be shorter and extend less than the full length between the front waist edge 136 and the back waist edge 138. Such a shorter configuration may be desirable in order to minimize the amount of total material used in the manufacture of the diaper 20.

Each of the side flaps 147a and 147b is attached to the interior surface 102 of the chassis 100 in attachment zones located in the front waist region 36 and in the back waist region 38. For example, in the chassis 100 shown in figure 1, the side flaps 147a and 147b are attached to the interior surface 102 of the chassis 100 in the adhesive attachment zones shown therein and more clearly seen in figure 10, figure 10 shows the chassis 100 laid out flat prior to the formation of the side flaps 147a and 147 b. In particular, the left side flap 147a is attached to the interior surface 102 of the chassis 100 in a longitudinally oriented adhesive attachment zone 151a adjacent to its proximal edge 157a near the front waist edge 136 and in a longitudinally opposing longitudinally oriented adhesive attachment zone 152a adjacent to its proximal edge 157a near the back waist edge 138. Likewise, the right side flap 147b is attached to the interior surface 102 of the chassis 100 in a longitudinally oriented adhesive attachment zone 151b adjacent to its proximal edge 157a near the front waist edge 136 and in a longitudinally opposing longitudinally oriented adhesive attachment zone 152b adjacent to its proximal edge 157b near the back waist edge 138. The areas of the adhesive attachment zones may be equal or unequal. For example, the longitudinally oriented front adhesive attachment zones 151a and 151b may be of one size and the longitudinally oriented back adhesive attachment zones 152a and 152b may be of another size.

In the exemplary chassis 100 shown in figure 1, the left side flap 147a is also attached to the interior surface 102 of the chassis 100 in a laterally oriented adhesive attachment zone 153a adjacent to the front waist edge 136 and in a longitudinally opposing laterally oriented adhesive attachment zone 154a adjacent to the back waist edge 138. Likewise, the right side flap 147b is also attached to the interior surface 102 of the chassis 100 in a laterally oriented adhesive attachment zone 153b adjacent to the front waist edge 136 and in a longitudinally opposing laterally oriented adhesive attachment zone 154b adjacent to the back waist edge 138. The areas of the adhesive attachment zones may be equal or unequal. For example, the laterally oriented front adhesive attachment zones 153a and 153b may be of one size and the laterally oriented back adhesive attachment zones 154a and 154b may be of another size.

Alternatively, each adhesive attachment zone may extend laterally across the full width of the respective side flap. For example, a laterally oriented adhesive attachment zone may extend laterally from the chassis left side edge 137a to the left side flap edge 157a and thereby attach the entire width of the left side flap 147a adjacent to the front waist edge 136 to the interior surface 102 of the chassis 100. In embodiments in which the front edge 236 or the back edge 238 of the absorbent assembly 200 coincides with the respective front waist edge 136 or back waist edge 138 of the chassis 100 and the side flaps 147a and 147b overlap the absorbent assembly 200, the side flaps 147a and 147b may be attached to the absorbent assembly 200 instead of or in addition to being attached to the interior surface 102 of the chassis 100.

Between the adhesive attachment zones, the proximal edges 157a and 157b of the side flaps 147a and 147b remain free, i.e., are not attached to the interior surface 102 of the chassis 100 or to the absorbent assembly 200. Also between the adhesive attachment zones, each side flap preferably includes a longitudinally extensible flap elastic member that is attached adjacent to the proximal edge of the side flap by any well-known means. Each such flap elastic member may be attached over its entire length or over only a portion of its length. For example, such a flap elastic member may be attached only at or near its longitudinally opposing ends and may not be attached at the middle of its length. Such a flap elastic member may be disposed in the crotch region 37 and may extend into one or both of the front waist region 36 and the back waist region 38. For example, in the exemplary chassis 100 shown in figure 1, an elastic strand 167a is attached adjacent to the proximal edge 157a of the left side flap 147a and extends into both the front waist region 36 and the back waist region 38. Similarly, an elastic strand 167b is attached adjacent to the proximal edge 157b of the right side flap 147b and extends into both the front waist region 36 and the back waist region 38.

Each flap elastic member may be enclosed in a folded hem. For example, in the exemplary chassis 100 shown in figure 4 and figure 5, the elastic strand 167a is enclosed inside a hem 170a formed adjacent to the proximal edge 157a of the left side flap 147a and the elastic strand 167b is enclosed inside a hem 170b formed adjacent to the proximal edge 157b of the right side flap 147 b. Alternatively, the flap elastic member may be sandwiched between two layers of the chassis, such as between the layers of a laminate backsheet or between a backsheet and an inner liner. Alternatively, the flap elastic member may be attached to the surface of the chassis 100 and remain exposed.

When stretched, the flap elastic member adjacent to each side flap edge allows the side flap edge to extend to the flat uncontracted length of the chassis, for example, the length of the chassis 100 as shown in figure 1. When allowed to relax, the flap elastic member contracts to gather the portion of the side flap edge along which the flap elastic member is attached and thereby make the relaxed length of the side flap edge less than the flat uncontracted length of the chassis. For example, when the exemplary diaper 20 is in a relaxed condition as shown in figure 16, the elastic strand 167a contracts to gather the proximal edge 157a of the left side flap 147a and the elastic strand 167b contracts to gather the proximal edge 157b of the right side flap 147 b. The contractive forces of the elastic strands 167a and 167b are transmitted at the respective front attachment zones 151a and 151b to the interior surface 102 of the chassis 100 at the front waist region 36. Likewise, the contractive forces of the elastic strands 167a and 167b are transmitted at the respective back attachment zones 152a and 152b to the interior surface 102 of the chassis 100 at the back waist region 38. These contractive forces pull the front waist region 36 and the back waist region 38 toward each other and thereby bend the diaper 20 into a "U" shape in which the interior of the "U" shape is formed by the portions of the diaper 20 that are intended to be placed toward the body of the wearer. Because the proximal edge 157a remains free between the attachment zones 151a and 152a, the contractive force of the elastic strand 167a lifts the proximal edge 157a away from the interior surface 102 of the chassis 100. Also, because the proximal edge 157b remains free between the attachment zones 151b and 152b, the contractive force of the elastic strand 167b lifts the proximal edge 157b away from the interior surface 102 of the chassis 100. As shown in figure 16, this raising of the proximal edges 157a and 157b raises the side flaps 147a and 147b into position to serve as side barriers adjacent to the side edges 237a and 237b of the absorbent assembly 200 when the diaper 20 is in a relaxed condition.

When the diaper 20 is worn, the relaxed "U" shape generally conforms to the body of the wearer such that the front waist region 36 and the back waist region 38 can be fastened together to encircle the waist and the legs of the wearer. When the diaper 20 is so worn, the elastic strands 167a and 167b tend to hold the raised proximal edges 157a and 157b of the side flaps 147a and 147b in contact with the body of the wearer and thereby form seals to help prevent the leakage of deposited bodily waste out of the diaper 20. The lateral spacing of the raised proximal edges 157a and 157b is selected to allow bodily waste from the lower torso of the wearer to be deposited into the space between the raised side flaps 147a and 147b and, thus, directly onto the absorbent assembly 200. The width of each side flap 147a and 147b effectively becomes its height when the free portion of its proximal edge is lifted and the side flaps serve as side barriers to leakage. This height is preferably selected to allow the raised proximal edges 157a and 157b to conform to the leg gathers of the wearer's body while maintaining the absorbent assembly 200 in contact with the body.

In the finished diaper, the chassis may have a generally rectangular shape, as in the exemplary diaper 20 shown in figure 1 and figure 2. Such a generally rectangular configuration may be desirable in order to minimize the amount of waste material and the difficulties associated with the manufacture of the diaper 20. Alternatively, the chassis may have side edges 137a and 137b that are not straight, but instead are curved and/or notched, thereby giving the overall shape of the diaper 20 in plan view an hourglass or an "I" shape. Such a non-rectangular configuration may be desirable in order to impart a particular appearance to the diaper 20 when it is worn. Such a non-rectangular configuration may also be desirable in order to create indentations that the diaper 20 will fit comfortably between the legs of a wearer. Any of a number of well-known methods may be used to form the non-rectangular configuration of the chassis. For example, laterally distal portions may be removed from the chassis to make its lateral dimension at or near the lateral axis 44 smaller than its lateral dimension at or near the front waist edge 136 or smaller than its lateral dimension at or near the back waist edge 138, i.e., to make the chassis narrower in the crotch region 37 than at the waist edges 136 and 138. Alternatively, a portion of each of the side edges 137a and 137b may be folded laterally inward to achieve the same result. Such folded portions of the side flaps 137a and 137b may be folded or attached, or both, to prevent their unfolding.

Figure 17 illustrates one exemplary form of a non-rectangular configuration of the chassis. As shown in this figure, the portions of the chassis extending laterally between the outer side edges and the respective side edges in one or both of the waist regions may remain laid out flat, i.e., may remain unfolded, when other portions are folded laterally inward to form the side flaps. For example, as shown in figure 17, the portions 106a and 106b extending longitudinally from the front waist edge 136 toward the lateral axis 44 in the front waist region 36 and extending laterally between each of the outer side edges 155a and 155b and the respective side edges 137a and 137b may be left laid out flat, i.e., may remain unfolded. Likewise, the portions 108a and 108b extending longitudinally from the back waist edge 138 toward the lateral axis 44 in the back waist region 38 and extending laterally between each of the outer side edges 155a and 155b and the respective side edges 137a and 137b may be left laid out flat, i.e., may remain unfolded. Other portions that remain unfolded and extend longitudinally between the portions that pass through the crotch region 37 may be folded laterally inward to form the side flaps 147a and 147 b. Portions 106a and 106b and portions 108a and 108b form "ears" that project laterally outward from each waist region of the diaper. These ears project laterally outward beyond the inwardly folded portions and impart an "I" shape to the diaper, as shown in FIG. 17. The portions need not remain unfolded at both ends as shown in fig. 17. For example, the portions 106a and 106b in the front waist region 36 may remain unfolded and only the portions 108a and 108b in the back waist region 38 may be folded laterally inward, or vice versa, in certain embodiments.

An alternative method of forming an "I" -shaped non-rectangular configuration of the chassis as shown in figure 17 is to form the chassis in an "I" -shape and attach an additional layer or layers to the interior surface of the "I" -shaped chassis at or adjacent to each of the side edges 137a and 137b of the chassis 100 to form the respective side flaps 147a and 147 b. In embodiments in which the side flaps are formed by attaching an additional layer or layers to the chassis, each additional layer may be attached at or adjacent to its laterally distal edge.

Figures 18 and 19 illustrate another exemplary method of forming a non-rectangular configuration of a chassis. As shown in these figures, laterally opposing portions 107a and 107b of the chassis between each of the side edges 137a and 137b and the respective proximal edges 157a and 157b of the side flaps 147a and 147b may be folded laterally inward in the crotch region 37 along respective diagonal fold lines 105a, 105b, 105c, and 105d such that each folded portion 107a and 107b of the chassis overlaps the absorbent assembly 200 in the crotch region 37. The interior surface 102 of each of the folded portions 107a and 107b may be attached to the interior surface 202 of the absorbent assembly in the crotch region 37 at attachment zones 109a and 109 b. This folding and attachment forms "W" shaped folds 112a and 112b in the chassis in the crotch region 37 as shown in figure 19, while retaining the configuration of the waist regions 36 and 38 as shown in figure 3 and figure 6. The overall effect on the chassis shape is to form an hourglass configuration as shown in figure 18. The attachment zones 109a and 109b may be disposed symmetrically with respect to either or both of the longitudinal axis 42 and the lateral axis 44. Alternatively, the attachment zones 109a and 109b may be disposed asymmetrically with respect to either or both of the longitudinal axis 42 and the lateral axis 44. For example, the attachment zones 109a and 109b shown in figure 18 are disposed symmetrically with respect to the longitudinal axis 42 and asymmetrically with respect to the lateral axis 44. In particular, the attachment zones 109a and 109b shown in figure 1 are disposed asymmetrically toward the front waist region 36.

Alternatively, the laterally opposing portions 107a and 107b of the chassis may be folded laterally inward in one or both of the waist regions in addition to being folded laterally inward in the crotch region. For example, to simplify the manufacture of the diaper, the laterally opposing portions 107a and 107b of the chassis may be folded laterally inward over their entire longitudinal lengths. The interior surface 102 of each folded portion 107a and 107b may be attached to the interior surface 202 of the absorbent assembly in the crotch region 37 at attachment zones 109a and 109 b. This folding and attachment forms "W" shaped folds 112a and 112b in the chassis as shown in figure 19 over the entire longitudinal length of the laterally opposing portions 107a and 107b of the chassis. When the disposable diaper for the configuration shown in figure 18 is prepared by unfolding laterally elongated laterally opposing portions at its longitudinal distal ends, the chassis may then be given an hourglass shape.

A portion or the entire chassis 100 may be made extensible to a degree greater than the inherent extensibility of the material or materials from which the chassis is made, such as the backsheet 26, the inner liner 22, or both. The additional extensibility may be desirable in order to allow the chassis 100 to conform to the body of a wearer during movement by the wearer. The additional extensibility may also be desirable, for example, in order to enable a user of a diaper 20 including a chassis 100 having a particular size before extension to extend the front waist region 36, the back waist region 38, or both waist regions of the chassis 100 to encircle the waist of an individual wearer whose waist circumference falls within a predetermined range, i.e., to tailor the diaper to the individual wearer. Such extension of the waist region may give the diaper a generally hourglass shape, so long as the crotch region 37 is extended to a relatively lesser degree than the waist region, and impart a tailored appearance to the diaper 20 when it is worn. In addition, the additional extensibility may be desirable in order to minimize the cost of the diaper. For example, an amount of material that is only sufficient to make a relatively smaller diaper lacking this extensibility can be used to make a diaper capable of being extended to fit a wearer greater than the smaller diaper would fit. In other words, a lesser amount of material is needed in order to make a diaper capable of being properly fitted onto a given size of wearer when the material is made extensible as described.

The additional extensibility in the chassis 100 in the lateral direction is relatively more useful than the additional extensibility in the longitudinal direction. The abdomen of the wearer is likely to expand when the wearer changes from a standing position to a sitting position and the corresponding abdominal expansion increases the circumference surrounded by the waist edges of the chassis 100, forcing the waist regions to expand laterally.

Additional lateral extensibility in the chassis 100 may be provided in a variety of ways. For example, the material from which the chassis 100 is made may be pleated by any known method. Alternatively, all or a portion of the chassis may be formed from a formed web material or a formed laminate web material, such as those described in U.S. Pat. No. 5,518,801 issued in the name of Chappell et al, 5/21 1996. An exemplary fragment 300 of such a formed web material 305 is shown in fig. 20. The formed web material 305 includes distinct laterally extending regions 310 in which the original material has been altered by embossing or another method of deformation to form a pattern of generally longitudinally oriented alternating ridges 312 and valleys 314. The formed web material 305 also includes non-altered laterally extending regions 316 located between the altered laterally extending regions 310.

Such a formed web material 305 can extend laterally beyond its original dimension with a relatively small force applied as compared to the force required to extend the same material to the same extent when undeformed. In particular, the effect of applying opposing divergent forces directed generally perpendicular to the ridges 312 and valleys 314 includes elongating such a formed web material along an axis between the opposing forces and generating a resistive contractive force, primarily in the unaltered regions 316. This resistance is relatively small compared to the resistance that would be generated if the same material in its unaltered form were elongated to the same extent at least to the extent where the ridges and valleys in the altered regions flatten and begin to contribute to the resistance. Thus, such formed web materials exhibit extensible properties similar to those of conventional elastic materials in the range of extensibility useful for the desired laterally extended pattern for use in absorbent articles. However, such formed web materials can be made from less expensive materials that are not inherently elastic, and thus their use can provide advantages in terms of the cost of manufacturing the absorbent article.

The range of extensibility of a web material or laminate formed as described in the Chappell et al' 801 patent can be controlled by varying the degree of deformation of the zones and can vary from near zero to a maximum amount, the maximum amount being determined by the original material. For example, the materials used in the chassis 100 of the exemplary diaper 20 may typically be shaped to provide any range of extensibility from approximately zero to a maximum amount exceeding 100% of the original dimension. In certain embodiments of the present invention, the maximum extensibility of a portion of the chassis 100 is approximately 20% of its original dimension. However, any particular value for the maximum extensibility may be selected within the range of from about 1% to about 100% to accommodate the particular choice of initial dimensions of the diaper 20 and the range of body sizes intended for the wearer. In particular, a diaper having a particular unextended waist opening circumference may be suitable for use on wearers having waist circumferences ranging from equal to the unextended waist opening circumference up to the maximum extensibility.

The front laterally central portion 117 and the back laterally central portion 118 of the chassis 100 between the attachment zones 151, 152, 153, and 154 attaching the side flaps 147a and 147b to the interior surface 102 of the chassis adjacent to the respective waist edges 137 and 138 may have a different range of extensibility than the portions of the chassis in the attachment zones. Additionally or alternatively, the laterally central portions 117 and 118 may be extensible to a greater or lesser degree when subjected to a given level of opposing tensile forces, i.e., may be more or less extensible, than the portions of the chassis in the attachment zones. For example, if the chassis is made uniformly extensible across its entire width prior to the formation of the side flaps, the two layering in the areas of the attachment zones after the formation of the side flaps may have the effect of reducing the degree of lateral extensibility of those areas under a given level of opposing tensile forces, such as by the side flaps acting as parallel "springs" that must be extended in order to extend the underlying attached portion of the chassis. As another example, the altered regions in the laterally central portions of the chassis may be deformed to a greater or lesser extent than the altered regions in the attachment zones to make the laterally central portions more or less extensible than the corresponding portions in the attachment zones.

Such a differential range of extensibility and/or such a differential relationship of tensile force to extensibility may be desirable. For example, when a diaper is applied to the body of a wearer and the user laterally extends the waist regions, each waist region is typically subjected to a generally uniform level of opposing tensile forces across its entire width so long as the user grasps the diaper at or adjacent to the laterally opposing side edges. If the laterally central portion of the chassis is less extensible than the portions in the attachment zones, the lateral spacing between the proximal edges 157a and 157b of the side flaps will increase less at a given level of applied tensile force than if the laterally central portion were as extensible or more extensible than the portions in the attachment zones. This effect of minimizing the variation in the lateral spacing between the side flaps may help to ensure that the diaper fits as intended on the wearer's body, for example by making it more likely that the proximal edges 157a and 157b of the side flaps will fit into the thigh folds of the body when the diaper is worn.

Any of a variety of materials may be formed as described in the Chappell et al' 801 patent. For example, a film, nonwoven, or laminate of either or both of these materials may be formed to provide the desired extensibility. While shaping to provide ductility, it is also possible to modify such a material in more than one way. For example, a film that is initially formed to resist the permeation of vapor through its thickness and that contains a particulate filter material such as calcium carbonate may be treated as described in the Chappell et al' 801 patent to simultaneously provide extensibility and create small holes that allow water vapor to pass through its thickness. Thus, the film can be made extensible and breathable at the same time.

The front waist region 36 and the back waist region 38 can be fastened together in many well-known ways to encircle the waist and the legs of the wearer. For example, separate fastening devices such as safety pins, separate adhesive tapes, separate support panels and/or separate belts may be employed for this purpose. Alternatively or in addition, fastening elements may be incorporated into the chassis 100 to enable a user to apply the diaper 20 to the body of the wearer without, or in conjunction with, any separate fastening devices. Many suitable types of such incorporated fastening elements are well known, including, for example, tapes, adhesives, tape tabs, ties, buttons, hooks, loops, snap fasteners, other forms of mechanical fasteners, cohesive patches, and the like. These incorporated fastening elements may project laterally outward, i.e., away from the longitudinal axis 42 beyond one or both of the side edges 137a and 137b and/or may project longitudinally outward, i.e., away from the lateral axis 44 beyond one or both of the waist edges 136 and 138, or they may lie entirely inside the edges of the diaper 20. When a laminate backsheet is employed and the nonwoven is disposed on a surface, some form of mechanical fastener, such as hooks that mate with loops, which typically require a particular mating fastener element, is configured to attach to the nonwoven, thereby eliminating the need to include the particular mating fastener element.

For example, as shown in figure 21 and figure 22, laterally opposing adhesive tape tabs 114a and 114b may be attached to the chassis 100 at or adjacent to the side edges 137a and 137b of the diaper 20. The adhesive tape tabs 114a and 114b shown in figure 21 and figure 22 project laterally outward from the respective side edges 137a and 137b in the back waist region 38. In use, the adhesive tape tabs 114a and 114b shown in figure 21 and figure 22 may be adhered to the exterior surface 104 of the chassis 100 in the front waist region 36 to fasten the back waist region 38 to the front waist region 36 in a back-over-front manner. Alternatively, similar adhesive tape tabs may be attached to the chassis 100 in the front waist region 36 and used to fasten the front waist region 36 to the back waist region 38 in a front-over-back manner. Suitable tapes are available from 3M Corporation of St.Paul, Minnesota, USA under the designation XMF 99121.

Each adhesive tape tab may be comprised of two or more layers, and different ones of the layers may be attached to different surfaces of the chassis. For example, as shown in figure 21 and figure 22, the inner layer 114c of the left adhesive tape tab 114a is attached to the left side flap 147a while the outer layer 114d of the left adhesive tape tab 114a is attached to the exterior surface 104 of the chassis 100. Likewise, the inner layer 114e of the right adhesive tape tab 114b is attached to the right side flap 147b while the outer layer 114f of the right adhesive tape tab 114b is attached to the exterior surface 104 of the chassis 100. This form of attachment between the adhesive tape tabs and the chassis provides the advantage that each of the inner and outer layers of each adhesive tape tab is subjected to substantially only shear forces at its attachment to the chassis, rather than both shear and peel forces. For example, any tendency of the interior layer 114c to peel away from the left side flap 147a is counteracted by the exterior layer 114d being subjected to a pulling force to prevent the interior layer 114c from peeling away. Conversely, any tendency of the outer layer 114d to peel away from the exterior surface 104 of the chassis 100 is counteracted by the inner layer 114c being subjected to a pulling force, preventing the outer layer 114d from peeling away. The outer layer of the adhesive tape tab shown in fig. 21 and 22 extends further toward the longitudinal axis than the inner layer of the adhesive tape tab. Alternatively, the inner layer may extend farther toward the longitudinal axis than the outer layer, or both layers may extend equally far toward the longitudinal axis. If the layers of material of the adhesive tape tab differ in tensile strength or the attachment of the adhesive tape tab is relatively more secure on one surface, the layer that is attached to the stronger material or more secure to the surface extends further toward the longitudinal axis so as to disproportionately distribute the force experienced by the adhesive tape tab to the stronger material or more secure attachment.

Optionally, a fastening sheet 116 may be attached to the exterior surface 104 of the chassis 100 in the front waist region 36 as shown in figure 21 and figure 22. The fastening sheet 116 shown in figure 21 and figure 22 is located completely inside the edges of the diaper 20. Alternatively, two or more discrete fastening sheets may be attached to the exterior surface of the chassis instead of a single fastening sheet. For example, two laterally opposing fastening sheets may be attached at positions approximately corresponding to the left and right portions of a single fastening sheet 116. When a fastening sheet is provided, the adhesive tape tabs may be adhered to the fastening sheet to fasten the back waist region 38 and the front waist region 36 together. The fastening sheet may be composed of a material used elsewhere in the diaper, such as a film or a nonwoven material. In embodiments where the chassis is extensible, it is preferred that any fastening sheet also be extensible such that the fastening sheet will not limit the extensibility of the portion of the chassis to which it is attached. For example, fastening sheets employ extensible nonwoven materials. The fastening sheet serves to distribute the tensile force transmitted by each of the adhesive tape tabs over an area of the backsheet 26 that is larger than the adhesive area of the adhesive tape tab. In addition, when a single fastening sheet such as the fastening sheet 116 in figure 21 and figure 22 is employed, the fastening sheet itself may bear a portion of the tensile force between the laterally opposing adhesive tape tabs, thereby relieving a portion of the force exerted on the backsheet. Thus, it may be desirable to incorporate such a fastening sheet, for example, to make it possible to use a less expensive and weaker material for the backsheet 26. The fastening sheet may be made of a material having a greater strength than the backsheet. Such a stronger material may be more expensive per unit area than the backsheet, whereas the fastening sheet is relatively smaller than the backsheet. Thus, the total cost of a diaper having a fastening sheet may be less than the total cost of a diaper having a backsheet with sufficient strength for the adhesive tape tabs to be adhered directly to the outer surface of the backsheet.

The exemplary fastening elements in the form of cohesive fastening patches described in this application and the specification for their configuration, configuration and use are intended to apply any type of incorporated fastening element as is practical for each such type of fastening element.

Exemplary fastening elements in the form of cohesive fastening patches may be made from inherently crystalline water-based synthetic elastomers to which a tackifier has been added to disrupt the polycrystalline structure, thereby rendering the elastomer cohesive. Such synthetic adhesive products are available from Andover coated products, Incorporated, of Salisbury, Mass., U.S. and are described in U.S. patent 6,156,424 issued to Taylor, 12.5.2000. The cohesive elastic fastening elements preferably remain extensible during use. Thus, when applied to an extensible chassis, such a cohesive elastic fastening element is capable of extending as the extensible chassis extends. Thus, when subjected to the hoop tensile forces typically present at the waist opening of a diaper when the diaper is worn, the attachment area between two cohesive elastic fastening elements to each other may be subjected to only shear forces rather than peel forces. This property enables the fastening elements to remain cohesive even when they are unfolded, as cohesive fastening elements typically exhibit relatively high resistance to shear forces versus peel forces.

Cohesive fastening patches may be formed by applying a cohesive material directly to the chassis or to a separate substrate that is in turn attached to the chassis. For example, a "hot melt" viscous material can be applied to a surface in its molten state and allowed to cool and solidify to form such a patch. The adhesive material may be applied in any pattern. Such as a continuous film, discrete dots, stripes, polygons, etc., and/or spaced apart and interconnected geometric elements describing a grid.

Exemplary cohesive fastening patches are shown enclosed in a chassis in fig. 1, 2, 3, 6, 10, 11, 12, 15, 23, and 24. In these exemplary embodiments, a cohesive fastening patch 110a is disposed on the exterior of the chassis 100 in the front waist region 36 adjacent to the right side edge 137a and a laterally opposing cohesive fastening patch 110b is disposed on the exterior of the chassis 100 in the front waist region 36 adjacent to the right side edge 137 b. A cohesive fastening patch 120a is disposed on the interior of the chassis 100 in the back waist region 38 adjacent to the left side edge 137a and a laterally opposing cohesive fastening patch 120b is disposed on the interior of the chassis 100 in the back waist region 38 adjacent to the right side edge 137 b. When the diaper 20 is worn as shown in figure 23 and figure 24, the left back cohesive fastening patch 120a overlaps the left front cohesive fastening patch 110a and the combination of the two cohesive fastening patches fastens the front waist region 36 and the back waist region 38 together at the left side of the diaper 20. Likewise, the right back cohesive fastening patch 120b overlaps the right front cohesive fastening patch 110b and the union of these two cohesive fastening patches fastens the front waist region 36 and the back waist region 38 together at the right side of the diaper 20. Thus, the configuration of the cohesive fastening patches shown in these figures is suitable for back-over-front fastening. Alternatively, the front cohesive fastening patches may be disposed on the interior of the chassis in the front waist region and the back cohesive fastening patches may be disposed on the exterior of the chassis in order to adapt the configuration of the cohesive fastening patches for front-over-back fastening. Fig. 23 and 24 show the cohesive fastening patches overlapped, however, not precisely aligned along any of their respective edges, for clarity of illustration only and may in fact be aligned as desired to maximize their overlapping area.

Alternatively, the cohesive fastening patches may be disposed in a reversible configuration that is adapted to provide the user of the diaper 20 with both options for fastening, i.e., either back-over-front or front-over-back, depending on personal preference. When cohesive fastening patches are disposed on both the exterior and the interior of the chassis 100, the back cohesive fastening patch may overlap the front cohesive fastening patch or the front cohesive fastening patch may overlap the back cohesive fastening patch and, in either arrangement, the cohesive fastening patches fasten the front waist region 36 and the back waist region 38 together at the sides of the diaper 20. Thus, with this configuration of cohesive fastening patches, the fastening of the diaper 20 on the side portions is reversible so that each side portion may be fastened back-over-front or alternatively front-over-back.

Two such reversible configurations of cohesive fastening patches are shown in fig. 25, 26, 27, and 28. In the first exemplary configuration, one cohesive fastening patch 110a wraps around the left side edge 137a and is disposed on the interior of the chassis 100 in the front waist region 36 adjacent to the left side edge 137 a. A laterally opposing cohesive fastening patch 110b wraps around the right side edge 137b and is disposed on both the exterior and the interior of the chassis 100 in the front waist region 36 adjacent to the right side edge 137 b. Such a continuous configuration may be desirable, for example, to enable the cohesive polymer of each cohesive fastening patch to be applied in a single area that is then folded when the corresponding folded side flap is formed during the manufacturing process.

In the second exemplary reversible configuration of cohesive fastening patches, the pair of back cohesive fastening patches 120a and 120b do not extend around the side edges 137a and 137b and, thus, are not continuous from the exterior to the interior of the chassis 100. Instead, a left back interior cohesive fastening patch 120a and a left back exterior cohesive fastening patch 120c are disposed on the respective interior and exterior of the chassis 100 adjacent to the left side edge 137a in the back waist region 38. Similarly, a back right interior cohesive fastening patch 120b and a back right exterior cohesive fastening patch 120d are disposed on the respective interior and exterior of the chassis 100 adjacent to the right side edge 137b in the back waist region 38. Such a discontinuous configuration may be desirable, for example, to enable the adhesive polymer to be applied after the side flaps are formed during the manufacturing process. In general, any or all of the cohesive fastening patches may extend around the side edges 137a and 137b or may be discontinuous from the exterior to the interior of the chassis 100.

As an alternative to overlapping cohesive fastening patches to fasten the front waist region 36 and the back waist region 38 together to encircle the waist and the legs of the wearer, the fastening patches may each be disposed on the interior surface of the chassis and may be joined in a face-to-face arrangement to form a flanged connection therein, e.g., a portion of the side edge 137a in the back waist region and a portion of the same side edge 137a in the front waist region are superposed, i.e., unlike an overlapped connection, in such a flanged connection, portions of the side edge are exposed.

The exemplary diaper shown in figure 1, figure 2, figure 3, figure 6, figure 10, figure 11, figure 12, figure 15, figure 23, and figure 24 includes discrete laterally opposing cohesive fastening patches. Alternatively, a single laterally extending cohesive fastening patch may be attached at each of the longitudinally opposing waist regions of the diaper. For example, each such individual cohesive fastening patch may extend laterally to about the lateral length defined by the distal edges of the discrete cohesive fastening patches shown in these figures. Thus, such a single cohesive fastening patch may have approximately the same length and be placed in approximately the same location as the fastening sheet 116 shown in figure 21 and figure 22.

Description of absorbent Assembly

As shown in figure 29, figure 30, and figure 31, the absorbent assembly 200 includes an absorbent core 250. The absorbent core 250 has a laterally extending front edge 256 in the front waist region 36 and a longitudinally opposing and laterally extending back edge 258 in the back waist region 38. The absorbent core 250 also has a longitudinally extending left side edge 257a and a laterally opposing and longitudinally extending right side edge 257b, both absorbent core side edges extending longitudinally between the front edge 256 and the back edge 258. Any or all of the respective front edge 256, back edge 258, left side edge 257a, and right side edge 257b of the absorbent core 250 may lie inward of the respective front edge 236, back edge 238, left side edge 237a, and right side edge 237b of the absorbent assembly 200. For example, in the exemplary absorbent assembly 200 shown in figure 29, the absorbent core 250 has its left side edge 257a and right side edge 257b disposed laterally inward of the respective left side edge 237a and right side edge 237b of the absorbent assembly 200. Alternatively, one or more of the edges of the absorbent core 250 may coincide with the corresponding edge or edges of the absorbent assembly 200. For example, in the exemplary absorbent assembly 200 shown in figure 29, the front edge 256 and back edge 258 of the absorbent core 250 coincide with the respective front edge 236 and back edge 238 of the absorbent assembly 200.

The absorbent assembly 200 may be attached to the chassis 100 over any portion or the entire area of the absorbent assembly 200. The absorbent assembly 200 is preferably attached to the chassis 100 on its exterior surface 204 in a cruciform attachment pattern, i.e., in an attachment pattern that forms or is arranged in a cross or "+" shape. The cruciform attachment pattern may be contiguous, i.e., all of its portions may be touching or connected throughout the pattern in an unbroken sequence. Alternatively, the cruciform attachment pattern may include discrete portions and thus not touching, but still be arranged such that the shape of the overall pattern is a cruciform. For example, a discontiguous cruciform attachment pattern may include a longitudinally extending portion disposed along the longitudinal axis and separate left and right laterally distal portions disposed along or adjacent to the lateral axis and thereby form a cruciform as the shape of the overall pattern.

An exemplary contiguous cruciform attachment pattern 210 is shown in figure 26, figure 29, figure 30, and figure 31. The portions of the chassis 100 that lie outside such a cruciform attachment pattern are not restrained by attachment to the absorbent assembly 200 and therefore remain extensible. In particular, a relatively narrow longitudinally extending portion 212 of a cruciform attachment pattern 210 like that shown in FIG. 29 and FIG. 31 leaves the majority of the width of the chassis 100 in the front waist region 36 and in the back waist region 38 freely extensible and thereby allows extension of the chassis 100 in the lateral direction in these regions. A relatively wide laterally extending portion 214 of a cruciform attachment pattern 210 like that shown in FIG. 29 and FIG. 30 prevents the portion of the chassis 100 in the crotch region 37 to which the absorbent assembly 200 is attached from shifting relative to the absorbent assembly 200 in that region. A relatively wide laterally extending portion 214 of a cruciform attachment pattern 210 may also contribute to the effectiveness of the side flaps 147a and 147b when the elastic strands 167a and 167b lift the proximal edges 157a and 157b into contact with the body of the wearer. For example, if the chassis 100 in the crotch region 37 were free to move laterally inward, i.e., toward the longitudinal axis 42, such that the left side edge 137a and/or the right side edge 137b moved toward the longitudinal axis 42, the side flaps 147a and 147b could easily distort and fail to maintain contact with the body. However, because the relatively wide laterally extending portion 214 of the cruciform attachment pattern 210 restrains the chassis 100 over a relatively wide portion of the width of the crotch region 37, the side flaps 147a and 147b are better supported at their bases when lifted by the elastic strands 167a and 167 b.

The cruciform attachment pattern 210 in figure 29, figure 30, and figure 31 extends laterally from near the left side edge 237a to near the right side edge 237b of the absorbent assembly 200 at and adjacent to the lateral axis 44, but does not extend laterally to this extent over the full length of the absorbent assembly 200. Similarly, the cruciform attachment pattern 210 in figure 29, figure 30, and figure 31 extends longitudinally from near the front edge 236 to near the back edge 238 of the absorbent assembly 200 at and adjacent to the longitudinal axis 42, but does not extend longitudinally to this extent over the full width of the absorbent assembly 200. Alternatively, the cruciform attachment pattern 210 may extend to any or all of the side edges 237a and 237b and the front edge 236 and the back edge 238 of the absorbent assembly 200. For example, a cruciform attachment pattern 210 may extend laterally from the left side edge 237a to the right side edge 237b of the absorbent assembly 200, but may extend longitudinally only a portion of the distance from the front edge 236 to the back edge 238 of the absorbent assembly 200. Within the extent of the cruciform attachment pattern 210, the absorbent assembly 200 may be attached to the chassis 100 continuously or intermittently. For example, a sheet of adhesive film may be continuously applied over the entire area of the cruciform attachment pattern and the absorbent assembly may then be continuously attached to the chassis. As an alternative example, an adhesive may be applied discontinuously at and inside the boundaries of the cruciform attachment pattern, such as in the form of dots, stripes, beads, spirals, etc., and then the absorbent assembly may be attached to the chassis.

The cruciform attachment pattern 210 may be disposed symmetrically with respect to either or both of the longitudinal axis 42 and the lateral axis 44 of the chassis 100. Alternatively, the cruciform attachment pattern 210 may be disposed asymmetrically with respect to either or both of the longitudinal axis 42 and the lateral axis 44. For example, the cruciform attachment pattern 210 shown in FIG. 29 is disposed symmetrically with respect to the longitudinal axis 42 and asymmetrically with respect to the lateral axis 44. In particular, the cruciform attachment pattern 210 shown in figure 29 is disposed asymmetrically toward the front waist region 36. Likewise, the laterally extending portion 214 of the cruciform attachment pattern 210 may be disposed away from the lateral axis 44 and the longitudinally extending portion 212 of the cruciform attachment pattern 210 may likewise be disposed away from the longitudinal axis 42. In addition, the cruciform attachment pattern 210 may be disposed symmetrically with respect to either or both of the side edges 237a and 237b and the front edge 236 and the back edge 238 of the absorbent assembly 200. For example, the cruciform attachment pattern 210 shown in figure 29 is disposed symmetrically with respect to both the side edges 237a and 237b and the front edge 236 and the back edge 238, i.e., the cruciform attachment pattern 210 shown in figure 29 is centered on the absorbent assembly 200. Alternatively, the cruciform attachment pattern 210 may be disposed asymmetrically with respect to either of the side edges 237a and 237b and the front edge 236 and the back edge 238 of the absorbent assembly 200, i.e., the cruciform attachment pattern 210 may be disposed off-center on the absorbent assembly 200.

The absorbent core 250 may be disposed between a lower covering sheet that is disposed on the exterior face of the absorbent core 250 in a face-to-face arrangement with the interior surface 102 of the chassis and an upper covering sheet that is disposed on the interior face of the absorbent core 250. Such an upper covering sheet and lower covering sheet may be attached together to contain the absorbent core 250 between them and thereby form the absorbent assembly 200. For example, in the exemplary absorbent assembly 200 shown in figure 29, figure 30, and figure 31, an upper covering sheet 24 and a lower covering sheet 25 are attached together at or adjacent to the side edges 237a and 237b of the absorbent assembly 200 in longitudinally extending adhesive attachment zones 29a and 29 b. Alternatively, the upper covering sheet 24 and the lower covering sheet 25 may be attached together in places other than the side edges 237a and 237b of the absorbent assembly 200, such as at or adjacent to the end edges 236 and 238 of the absorbent assembly 200, or at or adjacent to both the end edges 236 and 238 and the side edges 237a and 237 b.

The upper covering sheet 24 is water-permeable and allows liquid waste to penetrate to the absorbent core 250, which absorbs the liquid waste. The lower covering sheet 25 may be water-impermeable. However, the lower covering sheet 25 is preferably water-permeable. In embodiments in which both the upper covering sheet 24 and the lower covering sheet 25 are water-permeable, any liquid waste that is deposited onto the upper covering sheet 24 but does not pass through the upper covering sheet 24 to the absorbent core 250 can flow around one edge of the absorbent assembly 200 to reach the lower covering sheet 25 and then pass through the lower covering sheet 25 to the absorbent core 250.

The upper covering sheet 24 may form the interior surface 202 of the absorbent assembly 200 that is intended to be placed against the body of the wearer. The upper covering sheet 24 is preferably made of a soft material that will not irritate the skin of the wearer. Many materials suitable for a water-permeable covering sheet, including synthetic nonwoven materials such as spunbonded or carded polypropylene, polyester, or rayon, are well known in the art. Likewise, many materials for the covering sheet that are water-impermeable, including the materials for the backsheet 26, are well-known in the art.

The upper covering sheet 24 and the lower covering sheet 25 may extend to the same width and the same length. Alternatively, one or more of the edges of one of the covering sheets may lie distally relative to the corresponding edge or edges of the other covering sheet. For example, the upper covering sheet may extend longitudinally only to an extent sufficient to cover the absorbent core and the lower covering sheet may extend longitudinally beyond the upper covering sheet toward or to the waist edge. Such an extended covering sheet may serve to isolate the skin of the wearer from a portion of the backsheet 26 as may be desirable, for example, when the diaper 20 is worn under conditions in which contact between the skin and a backsheet film could be uncomfortable.

Suitable absorbent materials for the absorbent core are well known and include cellulosic fibers in the form of comminuted wood pulp, which is generally referred to as "airfelt", layers or sheets of natural or synthetic fibrous material, superabsorbent polymers and the like. These absorbent materials may be used alone or in combination. Many known absorbent materials can be used in a dispersed form, i.e., in the form of fibers, granules, particles, and the like. Such a discrete form of absorbent material may be secured by an adhesive, attaching the discrete pieces together to form a coherent layer, or attaching the discrete pieces to a substrate layer, such as a cover sheet, or attaching the discrete pieces to each other and to the substrate layer.

Alternatively, the discrete form of the absorbent material may be immobilized in pockets formed by a layer of thermoplastic material, such as a hot melt adhesive, that intermittently contacts and adheres to a substrate, such as a covering sheet, while diverging away from the substrate at the pockets. Absorbent assemblies having such a structure are described in european patent applications 03002678.5 and 03002677.7, both filed on 12.2.2003 in the name of ehrperger et al and co-pending and commonly assigned U.S. patent applications 10/776,839 and 10/776,851, both filed on 11.2.2004 in the name of ehrperger et al, each having corresponding priority claims to the aforementioned european patent applications, an exemplary absorbent assembly 200 having such a structure is shown in fig. 32. In this absorbent assembly 200, the absorbent core 250 includes particles of superabsorbent polymer 270 that are contained inside pockets 280 formed by a layer 275 of a thermoplastic material. Such an absorbent core 250 does not contain cellulosic fibers. Alternatively, the absorbent core 250 may comprise both particles of superabsorbent polymer and airfelt and both materials may be contained within pockets formed by the layer of thermoplastic material. As shown in fig. 32, the layer 275 of the thermoplastic material intermittently contacts and adheres to the lower covering layer 25 at the areas of attachment 282. Between the attachment regions 282, the layer 275 diverges away from the lower covering sheet 25 to form the pockets 280. The layer 275 may have the form of a sheet of fibers of thermoplastic material wherein the liquid waste may penetrate to the particles 270 of superabsorbent polymer for absorption.

In FIG. 32, a separate upper covering sheet 24 is shown overlying the layer 275 of the thermoplastic material. Alternatively, the separate upper covering sheet 24 may be omitted and the layer 275 in the form of a fibrous sheet may serve as the upper covering sheet 24. As another alternative, two absorbent assemblies each like that shown in figure 32 except for the omission of the upper covering sheet 24 may be superposed with one absorbent assembly inverted such that its pockets nest into the recesses in the attachment regions 282 of the other absorbent assembly and the respective single covering sheets distally oppose each other. In such a combined absorbent assembly 200, the distally opposing individual covering sheets may serve as the upper covering sheet 24 and the lower covering sheet 25, respectively.

In the exemplary absorbent assembly 200 shown in figure 29, figure 30, and figure 31, the upper covering sheet 24 and the lower covering sheet 25 are of the same size, i.e., both the upper covering sheet 24 and the lower covering sheet 25 extend to the front edge 236 and back edge 238, as well as to the left side edge 237a and right side edge 237b of the absorbent assembly 200. Alternatively, the upper covering sheet 24 and the lower covering sheet 25 may differ in size. For example, the lower covering sheet 25 may be larger than the upper covering sheet 24 and may be wrapped over the side edges 257a and 257b of the absorbent core 250 onto the interior surface of the absorbent core 250, where the upper covering sheet 24 and the lower covering sheet 25 may be attached together. Alternatively, in place of a separate upper covering sheet 24 and a separate lower covering sheet 25, a single covering sheet may be wrapped around the absorbent core 250 and attached to itself to contain the absorbent core 250. Such a single covering sheet forms an upper layer and a lower layer when wrapped around the absorbent core 250, and in general, the separate upper covering sheet 24 and lower covering sheet 25 are described as such upper and lower layers being used to apply a wrapped single covering layer.

At a minimum, the absorbent core 250 is laterally enclosed by a covering sheet that is wrapped around the absorbent core 250 or attached together at or adjacent to the left side edge 237a and right side edge 237b of the absorbent assembly 200. For example, in the exemplary absorbent assembly 200 shown in figure 29, figure 30, and figure 31, an upper covering sheet 24 and a lower covering sheet 25 are attached together in left adhesive attachment zone 29a and right adhesive attachment zone 29b only at or adjacent to the respective left side edge 237a and right side edge 237b of the absorbent assembly 200. In this embodiment, the upper covering sheet 24 and the lower covering sheet 25 cannot be directly joined together at or adjacent to the front edge 236 and back edge 238 because the absorbent core 250 extends the full length of the absorbent assembly 200, i.e., the front edge 256 and back edge 258 of the absorbent core 250 coincide with the respective front edge 236 and back edge 238 of the absorbent assembly 200. In such an embodiment, the upper and lower layers of the covering sheet may each be attached to the absorbent core 250 at or adjacent to the front edge 256 and back edge 258 of the absorbent core 250. Additionally, sealants may be applied at or near the front edge 256 and back edge 258 of the absorbent core 250 to encapsulate any fibers or particles that may leak out of the absorbent core 250. Alternatively, instead of being contained only laterally by the covering sheet, the absorbent core 250 may also be contained longitudinally by upper and lower covering sheets that are attached together at or adjacent to the front edge 236 and back edge 238 of the absorbent assembly 200.

The intended scope of the reference claims and the claims is incorporated

All patents, patent applications, and any patents which issue thereon, as well as any corresponding published foreign patent applications, and all publications listed and/or referenced in this specification, are hereby incorporated by reference herein. It is not expressly admitted that any of the documents or combination of documents incorporated herein by reference teach or disclose the present invention.

While particular embodiments and/or individual features of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Furthermore, it should be clear that all combinations of the described embodiments and features are possible and can lead to preferred embodiments of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims (10)

1. A disposable diaper, the disposable diaper comprising:

a chassis having a front waist region, a back waist region and a crotch region between the waist regions, laterally opposing side edges defining a width thereof, longitudinally opposing front and back waist end edges defining a length thereof, an interior surface and an exterior surface, and comprising a water-impermeable backsheet and laterally opposing side flaps attached to the interior surface adjacent to a longitudinally distal end thereof, and each side flap having a longitudinally extending elastic gathering member attached adjacent to a proximal edge thereof; and

an absorbent assembly having a width and a length less than the chassis, attached to the interior surface of the chassis and having side edges and end edges disposed adjacent to the respective side edges and end edges of the chassis,

wherein at least a portion of the chassis is extensible.

2. The disposable diaper of claim 1 wherein the extensible portion of the chassis includes at least two distinct laterally extending altered regions, each region containing a generally longitudinally oriented pattern of alternating projections and valleys created by the deformed portion of the chassis and also containing an unaltered region between the altered regions such that the chassis portion can be laterally extended to a given extent with the application of relatively less force than is required to laterally extend the same portion of the chassis to the same given extent prior to deformation.

3. The disposable diaper of any of the preceding claims wherein at least a portion of the chassis in one of the waist regions is laterally extensible to a maximum extensibility greater than a maximum extensibility of at least a portion of the chassis in the crotch region such that a lateral extension of each of the portions to its maximum extensibility imparts an hourglass shape to the chassis.

4. The disposable diaper of any of the preceding claims wherein the side flap is attached to the interior surface of the chassis in laterally opposing attachment zones and the laterally central portion of the chassis between the attachment zones is laterally extensible to a different degree under a given level of laterally opposing tensile forces than the portion of the chassis in the attachment zones.

5. A disposable diaper, the disposable diaper comprising:

a chassis having a front waist region, a back waist region and a crotch region between the waist regions, laterally opposing side edges defining a width thereof, longitudinally opposing front and back waist end edges defining a length thereof, an interior surface and an exterior surface, and comprising a water-impermeable backsheet and laterally opposing side flaps attached to the interior surface adjacent to a longitudinally distal end thereof, and each side flap having a longitudinally extending elastic gathering member attached adjacent to a proximal edge thereof; and

an absorbent assembly having a width and a length less than the chassis, attached to the interior surface of the chassis and having side edges and end edges disposed proximate to the respective side edges and end edges of the chassis,

at least portions of the laterally opposing portions of the chassis between the respective side edges of the chassis and the respective proximal edges of the side flaps are folded laterally inward to cover the absorbent assembly and are attached to the interior surface of the absorbent assembly.

6. The disposable diaper of claim 5 wherein the chassis is given an hourglass shape.

7. The disposable diaper of claim 5 or claim 6 wherein the laterally opposing portions of the chassis are folded laterally inward over their entire longitudinal lengths and impart an hourglass shape to the chassis when the laterally opposing portions are laterally extended by unfolding at their longitudinal distal ends to prepare the disposable diaper for use.

8. A disposable diaper, the disposable diaper comprising:

a chassis having a front waist region, a back waist region and a crotch region between the waist regions, laterally opposing side edges defining a width thereof, longitudinally opposing front and back waist end edges defining a length thereof, an interior surface and an exterior surface, and comprising a water-impermeable backsheet and laterally opposing side flaps attached to the interior surface adjacent to a longitudinally distal end thereof, and each side flap having a longitudinally extending elastic gathering member attached adjacent to a proximal edge thereof; and

an absorbent assembly having a width and a length less than the chassis, attached to the interior surface of the chassis and having side edges and end edges disposed adjacent to the respective side edges and end edges of the chassis,

wherein laterally opposing portions of the chassis are folded laterally inward in at least the crotch region to form the side flaps, and the laterally opposing portions of the chassis remain unfolded in at least one of the waist regions such that they project laterally outward beyond the inwardly folded portions.

9. The disposable diaper of claim 8 wherein laterally opposing portions of the chassis in both of the waist regions remain unfolded to project laterally outward beyond the inwardly folded portions, thereby imparting an "I" shape to the chassis.

10. The disposable diaper of any of the preceding claims wherein the absorbent assembly is attached to the chassis in a cruciform attachment pattern.