U.S. patent application number 11/133818 was filed with the patent office on 2006-11-23 for disposable absorbent article having breathable side flaps.
Invention is credited to Michael Patrick Hayden, Gary Dean LaVon, Kevin Michael Smith.
Application Number | 20060264861 11/133818 |
Document ID | / |
Family ID | 36928438 |
Filed Date | 2006-11-23 |
United States Patent
Application |
20060264861 |
Kind Code |
A1 |
LaVon; Gary Dean ; et
al. |
November 23, 2006 |
Disposable absorbent article having breathable side flaps
Abstract
A simple disposable absorbent article including a chassis and an
absorbent assembly. The chassis includes a water-impermeable sheet
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 is smaller in width
and in length than the chassis. The side edges and end edges of the
absorbent assembly may be disposed proximally relative to the
respective side edges and end edges of the chassis. The absorbent
assembly includes an absorbent core that may contain superabsorbent
particles, which may be contained inside pockets. The chassis may
be extensible. The absorbent assembly may be in a cruciform pattern
to the chassis to allow portions of the chassis to extend
laterally.
Inventors: |
LaVon; Gary Dean; (Liberty
Township, OH) ; Smith; Kevin Michael; (Cincinnati,
OH) ; Hayden; Michael Patrick; (Mason, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY;INTELLECTUAL PROPERTY DIVISION
WINTON HILL BUSINESS CENTER - BOX 161
6110 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Family ID: |
36928438 |
Appl. No.: |
11/133818 |
Filed: |
May 20, 2005 |
Current U.S.
Class: |
604/385.201 ;
604/385.28 |
Current CPC
Class: |
A61F 2013/530481
20130101; A61F 13/5116 20130101; A61F 2013/587 20130101; A61F
13/4946 20130101; A61F 13/49413 20130101; A61F 2013/15121 20130101;
A61F 13/49017 20130101; A61F 2013/4948 20130101; A61F 2013/4512
20130101; A61F 13/53713 20130101; A61F 13/49019 20130101; A61F
13/4942 20130101; A61F 2013/530007 20130101 |
Class at
Publication: |
604/385.201 ;
604/385.28 |
International
Class: |
A61F 13/15 20060101
A61F013/15 |
Claims
1. A disposable diaper comprising: an absorbent assembly comprising
an absorbent core; and a chassis having a longitudinal axis, a
lateral axis, a front waist region having a front waist edge, a
back waist region having a back waist edge, a crotch region between
the waist regions, laterally opposing side edges extending between
the front waist edge and the back waist edge, an exterior surface,
and an interior surface, the chassis forming a waist opening and
two laterally opposing leg openings when the front waist region and
the back waist region are attached together, the chassis comprising
a water-impermeable center sheet having laterally opposing side
edges, an interior surface, and an exterior surface, the chassis
further comprising laterally opposing water-impermeable water
vapor-permeable side sheets attached to the center sheet adjacent
to its side edges, each of the side sheets being doubled and
thereby having first and second layers over substantially its
entire area, at least portions of the side sheets being folded
interiorly laterally inward to form laterally opposing breathable
side flaps, each of the side flaps being attached adjacent to its
longitudinally distal ends to the interior surface and having a
longitudinally extending elastic gathering member attached adjacent
to its proximal edge.
2. The disposable diaper of claim 1 wherein the first layer of the
doubled side sheet has an edge, the second layer of the doubled
side sheet has an edge, and the doubled side sheet is attached
adjacent to the edge of the first layer to the interior surface of
the center sheet and is attached adjacent to the edge of the second
layer to the exterior surface of the center sheet.
3. The disposable diaper of claim 1 wherein the first layer of the
doubled side sheet has an edge, the second layer of the doubled
side sheet has an edge, and the doubled side sheet is attached
adjacent to both the edge of the first layer and the edge of the
second layer to the exterior surface of the center sheet.
4. The disposable diaper of claim 1 wherein the first layer of the
doubled side sheet has an edge, the second layer of the doubled
side sheet has an edge, and the doubled side sheet is attached
adjacent to the edge of the first layer to the exterior surface of
the center sheet and is also attached to itself adjacent to both
the edge of the first layer and the edge of the second layer where
the second layer is overlapped onto the first layer.
5. The disposable diaper of claim 1 wherein the elastic gathering
member is sandwiched between the two layers of the doubled side
sheet.
6. The disposable diaper of claim 1 wherein the two layers of the
doubled side sheet are attached together in laterally spaced
attachment zones extending longitudinally through at least the
crotch region.
7. The disposable diaper of claim 1 wherein the two layers of the
doubled side sheet are attached together in laterally extending
attachment zones adjacent to each of the waist edges.
8. The disposable diaper of claim 7 wherein the two layers of the
doubled side sheet are attached together laterally continuously in
the laterally extending attachment zones.
9. The disposable diaper of claim 1 wherein at least a portion of
the chassis is laterally extensible.
10. The disposable diaper of claim 9 wherein the center sheet is
laterally extensible.
11. The disposable diaper of claim 9 wherein at least one of the
side sheets is laterally extensible.
12. The disposable diaper of claim 9 wherein the extensible portion
of the chassis is disposed in one of the waist regions and is
laterally extensible to a maximum extensibility greater than a
maximum extensibility of another 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.
13. A disposable diaper comprising: an absorbent assembly
comprising an absorbent core; and a chassis having a longitudinal
axis, a lateral axis, a front waist region, a back waist region, a
crotch region between the waist regions, laterally opposing side
edges extending between the front waist edge and the back waist
edge, an exterior surface, and an interior surface, the chassis
forming a waist opening and two laterally opposing leg openings
when the front waist region and the back waist region are attached
together, the chassis comprising a water-impermeable water
vapor-impermeable center sheet having laterally opposing side
edges, the chassis further comprising laterally opposing
water-impermeable water vapor-permeable side sheets attached to the
center sheet adjacent to its side edges, at least portions of the
side sheets being folded interiorly laterally inward to form
laterally opposing breathable side flaps, each of the side flaps
being attached adjacent to its longitudinally distal ends to the
interior surface and having a longitudinally extending elastic
gathering member attached adjacent to its proximal edge.
14. The disposable diaper of claim 13 wherein the elastic gathering
member is enclosed inside a hem formed adjacent to the proximal
edge of the side flap.
15. The disposable diaper of claim 13 wherein the side sheets are
attached to the exterior surface of the center sheet.
16. The disposable diaper of claim 13 wherein the side sheets are
attached to the interior surface of the center sheet.
17. The disposable diaper of claim 13 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
another 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.
18. A disposable diaper comprising: a chassis having a longitudinal
axis, a lateral axis, a front waist region, a back waist region, a
crotch region between the waist regions, laterally opposing side
edges extending between the front waist edge and the back waist
edge, an exterior surface, and an interior surface, the chassis
forming a waist opening and two laterally opposing leg openings
when the front waist region and the back waist region are attached
together, the chassis comprising a water-impermeable center sheet
having laterally opposing side edges, the chassis further
comprising laterally opposing water-impermeable water
vapor-permeable side sheets attached to the center sheet adjacent
to its side edges, at least portions of the side sheets being
folded interiorly laterally inward to form laterally opposing
breathable side flaps, each of the side flaps being attached
adjacent to its longitudinally distal ends to the interior surface
and having a longitudinally extending elastic gathering member
attached adjacent to its proximal edge; and an absorbent assembly
comprising an absorbent core and being attached to the chassis in a
cruciform pattern of attachment having a longitudinally extending
portion intersecting with a laterally extending portion.
19. The disposable diaper of claim 18 wherein the longitudinally
extending portion is disposed symmetrically with respect to the
longitudinal axis and the laterally extending portion is disposed
asymmetrically with respect to the lateral axis.
20. The disposable diaper of claim 19 wherein the laterally
extending portion is offset toward the front waist region.
Description
FIELD OF THE INVENTION
[0001] This invention relates to disposable absorbent articles such
as disposable diapers and other articles intended for use on
incontinent persons.
BACKGROUND OF THE INVENTION
[0002] 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.
[0003] As the usage of disposable absorbent articles has expanded,
their complexity has increased with the incorporation of additional
features serving to enhance their performance and appearance. The
costs of the materials and the costs of the manufacturing processes
have also increased in conjunction with the increase in complexity.
As a result, the prices at which these articles are sold have risen
to levels that many potential purchasers around the world cannot
afford to pay. Thus, a need exists for a simple disposable
absorbent article.
SUMMARY OF THE INVENTION
[0004] A disposable absorbent article includes a chassis and an
absorbent assembly. The chassis includes a water-impermeable center
sheet and laterally opposing water vapor-permeable side sheets
attached to the center sheet adjacent to its side edges. Laterally
opposing portions of the chassis are folded laterally inward and
attached to the interior surface of the chassis adjacent to its end
edges to form breathable side flaps. Each side flap has a
longitudinally extending elastic gathering member attached adjacent
to its proximal edge. The absorbent assembly is smaller in width
and in length than the chassis. The side edges and end edges of the
absorbent assembly may be disposed proximally relative to the
respective side edges and end edges of the chassis. The absorbent
assembly includes an absorbent core. The absorbent core may contain
superabsorbent particles and these particles may be contained
inside pockets. The chassis center sheet may be laterally
extensible and may include 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] In the accompanying drawing figures, like reference numerals
identify like elements, which may or may not be identical in the
several exemplary embodiments that are depicted. Some of the
figures may have been 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.
[0006] 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.
[0007] 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.
[0008] FIG. 3 is a section view of the diaper 20 of FIG. 1 taken at
the section line 3-3.
[0009] FIG. 4 is a section view of the diaper 20 of FIG. 1 taken at
the section line 4-4.
[0010] FIG. 5 is a section view of the diaper 20 of FIG. 1 taken at
the section line 5-5.
[0011] FIG. 6 is a section view of the diaper 20 of FIG. 1 taken at
the section line 6-6.
[0012] FIG. 7 is a simplified side elevation view of an exemplary
diaper 20 being worn about a lower torso of a wearer.
[0013] FIG. 8 is a front elevation view of the diaper 20 of FIG. 7
being worn about the lower torso of the wearer.
[0014] FIG. 9 is a back elevation view of the diaper 20 of FIG. 7
being worn about the lower torso of the wearer.
[0015] FIG. 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 FIG. 10, the interior portion
of the diaper 20 that faces inwardly toward the wearer and contacts
the wearer is shown facing the viewer.
[0016] 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
viewer.
[0017] FIG. 12 is a section view of the diaper 20 of FIG. 10 taken
at the section line 12-12.
[0018] FIG. 13 is a section view of the diaper 20 of FIG. 10 taken
at the section line 13-13.
[0019] FIG. 14 is a section view of an alternative embodiment of
the diaper 20 of FIG. 1 taken at the section line 44.
[0020] FIG. 15 is a section view of an alternative embodiment of
the diaper 20 of FIG. 1 taken at the section line 44.
[0021] FIG. 16 is a section view of an alternative embodiment of
the diaper 20 of FIG. 1 taken at the section line 4-4.
[0022] FIG. 17 is 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 are left laid out
flat when other portions are folded laterally inward to form the
side flaps 147a and 147b.
[0023] FIG. 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 portions of the chassis are folded
over and attached to the interior surface of the absorbent assembly
to impart an hourglass shape to the diaper 20.
[0024] FIG. 19 is a section view of the diaper 20 of FIG. 18 taken
at the section line 19-19.
[0025] FIG. 20 is a plan view of an exemplary fragment of a formed
web material.
[0026] FIG. 21 is a simplified 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, having adhesive tape tabs 114a and 114b and a
fastening surface 116 attached to the chassis. In FIG. 21, the
exterior portion of the diaper 20 that faces outwardly away from
the wearer is shown facing the viewer.
[0027] FIG. 22 is a plan view of an exemplary absorbent assembly
200. In FIG. 22, the absorbent assembly 200 is shown separately
from a chassis 100 to which it is attached 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.
[0028] FIG. 23 is a section view of the absorbent assembly 200 of
FIG. 22 taken at the section line 23-23.
[0029] FIG. 24 is a section view of the absorbent assembly 200 of
FIG. 22 taken at the section line 24-24.
[0030] FIG. 25 is a section view of an exemplary absorbent assembly
200.
[0031] FIG. 26 is a section view of an exemplary absorbent assembly
200.
DETAILED DESCRIPTION OF THE INVENTION
[0032] In this description, the following terms have the following
meanings:
[0033] 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.
[0034] 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.
[0035] The term "disposable" refers 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.
[0036] The term "longitudinal" refers to a direction running from a
waist edge to an opposing waist edge of the article and generally
parallel to the maximum linear dimension of the article. Directions
within 45 degrees of the longitudinal direction are considered to
be "longitudinal".
[0037] The term "lateral" refers to a direction running from a side
edge to an opposing side edge of the article and generally at a
right angle to the longitudinal direction. Directions within 45
degrees of the lateral direction are considered to be
"lateral".
[0038] The term "disposed" refers to an element being attached and
positioned in a particular place or position in a unitary structure
with other elements.
[0039] The term "attached" refers to elements being connected or
united by fastening, adhering, bonding, etc. by any method suitable
for the elements being attached together and their constituent
materials. Many suitable methods for attaching elements together
are well-known, including adhesive bonding, pressure bonding,
thermal bonding, mechanical fastening, etc. Such attachment methods
may be used to attach elements together over a particular area
either continuously or intermittently.
[0040] The term "cohesive" refers to the property of a material
that sticks to itself but does not to any significant degree stick
to other materials.
[0041] The terms "water-permeable" and "water-impermeable" refer to
the penetrability of materials in the context of the intended usage
of disposable absorbent articles. Specifically, 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
"water vapor-permeable". Such a water vapor-permeable layer or
layered structure is commonly known in the art as "breathable". As
is well known in the art, a common method for measuring the
permeability to water of the materials typically used in absorbent
articles is a hydrostatic pressure test, also called a hydrostatic
head test or simply a "hydrohead" test. Suitable well known
compendial methods for hydrohead testing are approved by INDA
(formerly the International Nonwovens and Disposables Association,
now The Association of the Nonwoven Fabrics Industry) and EDANA
(European Disposables and Nonwovens Association).
[0042] The terms "proximal" and "distal" refer respectively to the
location of an element relatively near to or far from the center of
a structure, e.g., the proximal edge of a longitudinally extending
element is located nearer to the longitudinal axis than the distal
edge of the same element is located relative to the same
longitudinal axis.
[0043] The terms "interior" and "exterior" refer respectively to
the location of an element that is intended to be placed against or
toward the body of a wearer when an absorbent article is worn and
the location of an element that is intended to be placed against or
toward any clothing that is worn over the absorbent article.
Synonyms for "interior" and "exterior" include, respectively,
"inner" and "outer", as well as "inside" and "outside". Also, when
the absorbent article is oriented such that its interior faces
upward, e.g., when it is laid out in preparation for setting the
wearer on top of it, synonyms include "upper" and "lower", "above"
and "below", "over" and "under", and "top" and "bottom",
respectively.
[0044] In the following description and in the drawing figures,
various structural elements are identified by reference numerals
without suffixed letters when referring to the group as a whole and
by the same reference numerals with suffixed letters when
distinguishing between, for example, left and right members of the
group. As an example, the side flaps as a group are identified by
the reference numeral 147 while the individual left and right side
flaps are respectively designated as elements 147a and 147b.
Description of Exemplary Diaper Embodiment
[0045] Reference is made to FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5,
FIG. 6, FIG. 7, FIG. 8, and FIG. 9 for this section of this
description.
[0046] One end portion of the exemplary diaper 20 is configured as
a front waist region 36. The longitudinally opposing end portion of
the diaper 20 is 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.
[0047] 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 back 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 exterior surface 104 is intended to be placed toward any
clothing that is worn over the diaper 20. 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
through 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 through the midpoint of the right side edge 137b of
the chassis 100. The exemplary chassis 100 shown in FIG. 1
additionally has longitudinally extending and laterally opposing
water vapor-permeable, i.e., breathable, side flaps 147a and 147b
that are described in more detail below.
[0048] The basic structure of the diaper 20 also includes an
absorbent assembly 200 that is 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 either or both of 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 FIG. 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 FIG. 1 is disposed
asymmetrically toward the front waist region 36.
[0049] 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 FIG. 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 relatively thicker and relatively less flexible
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.
[0050] 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 at the same time the side edges 137a and
137b encircle the legs of the wearer. At the same time, 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 Chassis
[0051] In FIG. 10, FIG. 11, FIG. 12, and FIG. 13, the exemplary
chassis 100 is shown laid out flat before the breathable side flaps
147a and 147b are formed by folding portions of the chassis 100
laterally inward, i.e., toward the longitudinal axis 42. In this
condition of being laid out flat, the chassis 100 has a
longitudinally extending left outer side edge 155a and a laterally
opposing and longitudinally extending right outer side edge 155b.
Both of these outer side edges extend longitudinally between the
front waist edge 136 and the back waist edge 138. As is described
in more detail below, when the breathable side flaps 147 are formed
by folding portions of the chassis 100 laterally inward, the outer
side edges 155 of the chassis form the proximal edges 157 of the
side flaps.
[0052] The chassis 100 includes a water-impermeable center sheet 26
having a left side edge 126a and a right side edge 126b. Many
suitable materials for use as the center sheet 26 are well-known,
including films of polyethylene and other polyolefins. Multi-layer
center sheets, such as laminates of a film and a nonwoven, are also
well-known and may be suitable for use as the center sheet 26. Such
a laminate center sheet may be oriented with the nonwoven disposed
exteriorly to provide the feel and appearance of a more cloth-like
outermost layer than would be provided by using the film as the
outermost layer.
[0053] The chassis 100 may, but need not, additionally include an
inner liner 22, as shown in FIG. 14, FIG. 15, and FIG. 16. 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
the wearer. For example, the inner liner may cover and thereby lie
interiorly of a portion or all of the absorbent assembly 200. The
inner liner 22 preferably is formed of a soft material that will
not irritate the skin of the wearer. Such an inner liner 22 may
serve to isolate the skin of the wearer from a portion of the
center sheet 26 as may be desirable, for example, when the diaper
20 is worn under conditions in which contact between the skin and a
center sheet 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.
[0054] The inner liner 22 may extend to the edges of the chassis
100. Alternatively, one or more of the edges of the inner liner 22
may lie inward of the edges of the chassis 100. For example, with
reference to the exemplary diaper 20 shown in FIG. 1, only the
portions of the center sheet 26 lying in the gaps 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 would
need to be covered in order to isolate the skin of the wearer from
the center sheet 26. 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.
[0055] The chassis 100 includes longitudinally extending laterally
opposing side sheets 60 attached to the center sheet 26 adjacent to
its side edges 126. For example, the side sheets may be attached to
the center sheet by continuous, water impermeable bonds or seals
made by any of several known methods, such as the application of
adhesives, mechanical bonding, and thermal bonding, or a
combination of known bonding methods.
[0056] When the exemplary chassis 100 is laid out flat, each side
sheet 60 overlaps the center sheet 26 such that the proximal edge
61a of the left side sheet 60a lies laterally inward of the left
side edge 126a of the center sheet 26 and the proximal edge 61b of
the right side sheet 60b lies laterally inward of the right side
edge 126b of the center sheet 26. Each side sheet 60 extends
laterally outwardly from its proximal edge 61 past the respective
side edge 126 of the center sheet 26 to its distal edge 62. Thus,
the distal edges 62 of the side sheets 60 form the outer side edges
155 of the chassis 100 in this laid out flat condition.
[0057] Each side sheet 60 may be doubled over substantially its
entire area, either by folding the side sheet or by adding a second
layer to the side sheet. For example, as shown in FIG. 3, FIG. 4,
FIG. 5, and FIG. 6, each side flap 147 may include two layers 63
and 64 of the respective doubled side sheet 60 and the respective
flap elastic member may be sandwiched between the two layers. In
this embodiment, the distal edge 62 of each side sheet 60 is formed
where the side sheet is folded for doubling. The proximal edge 61
of each side sheet 60 is doubled by the doubling of the side sheet.
Such a doubled side sheet 60 may be attached to the interior
surface 122 of the center sheet 26 adjacent to the proximal edge
61c of its first layer 63 and attached to the exterior surface 124
of the center sheet 26 adjacent to the proximal edge 61d of its
second layer 64 as shown in FIG. 3, FIG. 4, FIG. 5, and FIG. 6.
[0058] Alternatively, such a doubled side sheet 60 may be attached
to either the exterior surface 124 or the interior surface 122 of
the center sheet 26 adjacent to both of its proximal edges 61. For
example, each of the doubled side sheets 60 shown in FIG. 14 is
attached to the exterior surface 124 of the center sheet 26
adjacent to both of its proximal edges 61. Another example is shown
in FIG. 15, in which each of the doubled side sheets 60 is attached
to the exterior surface 124 of the center sheet 26 adjacent to the
proximal edge 61c of its first layer 63 and also attached to itself
adjacent to both the proximal edge 61c of its first layer 63 and
the proximal edge 61d of its second layer 64 by overlapping its
second layer 64 onto its first layer 63.
[0059] The layers of each doubled side sheet 60 may remain
unattached to each other and thus free to contact each other or
separate from each other. Alternatively, the layers of each doubled
side sheet 60 may be attached together laterally continuously or
intermittently between the proximal edges 61 and the proximal edge
157 of the side flap 147. For example, the layers of each doubled
side sheet 60 may be attached together by adhesives, mechanical
bonds, or thermal bonds, or by a combination of known bonding
methods.
[0060] In the exemplary embodiment shown in FIG. 1, FIG. 2, FIG. 4,
and FIG. 5, the layers are attached together in laterally spaced
attachment zones 160 extending longitudinally through the crotch
region 37 and into the waist regions 36 and 38. Such longitudinally
extending attachment together prevents the layers from separating
and thereby presenting an undesirable baggy or blousy appearance
around the legs of the wearer, as well as tending to stiffen the
side flaps 147 slightly and thereby helping to ensure their proper
fit against the body.
[0061] Alternatively, or in addition, the layers of the each
doubled side sheet 60 may be attached together in the waist regions
36 and 38 adjacent to the waist edges 136 and 138, for example in
laterally extending attachment zones 159 as shown in FIG. 1, FIG.
2, FIG. 3, and FIG. 6. This lateral attachment may be laterally
intermittent or laterally continuous. When such laterally extending
attachment is continuous, it prevents the layers from separating
and thereby presenting an undesirable unfinished appearance at the
waist edges, as well as preventing the leakage at the waist edge of
any liquid waste from between the layers.
[0062] Alternatively, each side sheet 60 may have the form of a
single layer. For example, as shown in FIG. 16, a side sheet 60 may
be attached adjacent to its proximal edge 61 onto either the
interior surface 122 or the exterior surface 124 of the center
sheet 26 and incorporated into a side flap 147. In this embodiment,
the side flap 147 includes only a single layer of the side sheet 60
everywhere except along the proximal edge 157 of the side flap,
where the side sheet is doubled to form a folded hem 170 to
sandwich a flap elastic member.
[0063] Exemplary materials suitable for use in the side sheets 60
include polyolefinic films, microporous or other breathable formed
films, breathable monolithic films, and hydrophobic nonwovens.
Suitable hydrophobic nonwovens include SM (spunbond meltblown), SMS
(spunbond meltblown spunbond), and SMMS (spunbond meltblown
meltblown spunbond) composites. The materials of the water
vapor-permeable side sheets may be selected to balance overall
product economics and function. For example, a relatively more
expensive nonwoven material having a relatively high basis weight
may provide an acceptable level of water-impermeability for use in
a single layer side flap construction. Alternatively, a relatively
less expensive nonwoven having a relatively lower basis weight may
provide the requisite level of water-impermeability only if it is
doubled, thereby requiring a relatively greater area of material.
As another example, a microporous film may provide a relatively
optimal combination of water-impermeability and material cost.
[0064] As shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG.
6, the exemplary chassis 100 has longitudinally extending and
laterally opposing breathable 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
are formed by folding portions of the chassis 100 including the
water vapor-permeable side sheets 60 laterally inward, i.e., toward
the longitudinal axis 42, to form both the respective side flaps
147a and 147b and the side edges 137a and 137b of the chassis 100.
The side sheets 60 of the chassis 100 may be folded laterally
inward as shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG.
6 to form the side flaps. Alternatively, the chassis may be folded
such that each side flap includes the respective side sheet 60 and
a portion of the center sheet 26, as shown in FIG. 19. In either
configuration, at least a portion of each side flap is breathable
due to its inclusion of at least a portion of the respective water
vapor-permeable side sheet.
[0065] The chassis 100 may simply be folded loosely or may be
creased along a portion of each of its side edges 137. For example,
it may be desirable to form creases along portions of the side
edges 137 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 147
adjacent to the side edges 137 may be attached to the interior
surface 102 of the chassis 100 to achieve a similar result.
[0066] Each side flap 147 has a proximal edge 157. In the exemplary
diaper 20 shown in FIG. 1, the side flaps 147 overlap the absorbent
assembly 200, i.e., the proximal edges 157 lie laterally inward of
the respective side edges 237 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 that imparted by a
non-overlapped configuration. Alternatively, the side flaps 147 may
not overlap the absorbent assembly 200, i.e., the proximal edges
157 may lie laterally outward of the respective side edges 237 of
the absorbent assembly 200.
[0067] In the exemplary chassis 100 shown in FIG. 1, the side flaps
147 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 difficulty associated with the manufacture
of the diaper 20, especially when the method used to manufacture
the diaper 20 requires the introduction of the material or
materials 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 distance between the front
waist edge 136 and the back waist edge 138. Such a shorter
configuration may be desirable in order to minimize the total
amount of material used in the manufacture of the diaper 20.
[0068] Each of the breathable side flaps 147 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 FIG. 1, the side flaps 147 are
attached to the interior surface 102 of the chassis 100 in the
adhesive attachment zones that are shown there and that are more
clearly visible in FIG. 10, where the chassis 100 is shown laid out
flat before the side flaps 147 are formed. In particular, each side
flap 147 is attached to the interior surface 102 of the chassis 100
in an attachment zone 153 adjacent to the front waist edge 136 and
in a longitudinally opposing attachment zone 154 adjacent to the
back waist edge 138. The attachment zones may have equal areas or
may be unequal in area. For example, the front attachment zones 153
may be of one size and the back attachment zones 154 may be of
another size.
[0069] Alternatively, each 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 side edge 137 to the side flap proximal edge 157
and thereby attach the entire width of the side flap 147 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 147 overlap the absorbent assembly
200, the side flaps 147 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.
[0070] Between the attachment zones, the proximal edges 157 of the
side flaps 147 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 attachment zones, each breathable side flap
preferably includes a longitudinally extensible flap elastic member
that is attached adjacent to the proximal edge of the side flap by
any of many 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 be
unattached 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 FIG. 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.
[0071] Each flap elastic member may be enclosed inside a folded
hem. For example, in the exemplary chassis 100 shown in FIG. 4 and
FIG. 5, each elastic strand 167 is enclosed inside a hem 170 formed
adjacent to the proximal edge 157 of the respective side flap 147.
Alternatively, the flap elastic member may be sandwiched between
two layers of the chassis, e.g., between the layers of the side
flap or between the side flap and a separate material such as an
inner liner. As another alternative, the flap elastic member may be
attached on a surface of the chassis 100 and remain exposed.
[0072] 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, e.g., the length of the chassis
100, as shown in FIG. 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. Thus, when the exemplary diaper
20 is in a relaxed condition, each elastic strand 167 contracts to
gather the proximal edge 157 of the respective side flap 147. The
contractive forces of the elastic strands 167 are transmitted at
the respective front attachment zones 153 to the interior surface
102 of the chassis 100 at the front waist region 36. Similarly, the
contractive forces of the elastic strands 167 are transmitted at
the respective back attachment zones 154 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 157
remains free between the attachment zones, the contractive force of
the elastic strand 167 lifts the proximal edge 157 away from the
interior surface 102 of the chassis 100. This lifting of the
proximal edges 157 when the diaper 20 is in the relaxed condition
lifts the side flaps 147 into position to serve as side barriers
adjacent to the side edges 237 of the absorbent assembly 200.
[0073] When the diaper 20 is worm, 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 worn in this manner, the elastic strands 167 tend to hold the
lifted proximal edges 157 of the side flaps 147 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 lifted proximal edges 157 is selected to allow the
deposit of bodily wastes from the lower torso of the wearer into
the space between the lifted side flaps 147 and thereby directly
onto the absorbent assembly 200. The width of each of the side
flaps 147 in effect becomes its height when the free portion of its
proximal edge is lifted and the side flap serves as a side barrier
to leakage. This height preferably is selected to allow the lifted
proximal edges 157 to fit into the leg creases of the body of the
wearer at the same time as the absorbent assembly 200 is held in
contact with the body.
[0074] In the finished diaper, the chassis may have a generally
rectangular shape, as in the exemplary diaper 20 shown in FIG. 1
and FIG. 2. Such a generally rectangular configuration may be
desirable in order to minimize the amount of waste material and the
difficulty 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 an overall shape in plan view of an hourglass or of an "I"
to the diaper 20. This shape may help to conform the diaper 20 to
the contour of the wearer's body in use. Such a shape may also be
desirable in order to impart a tailored appearance to the diaper 20
when it is worn and/or to impart an impression that the diaper 20
will fit comfortably between the legs of a wearer. Any one of many
well-known ways may be used to form a non-rectangular configuration
of the chassis. For example, laterally distal portions may be
removed from the chassis to make its lateral dimension at and
adjacent to the lateral axis 44 smaller than its lateral dimension
at and adjacent to the front waist edge 136 and smaller than its
lateral dimension at and adjacent to 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 in order to
achieve the same result. Such folded portions of the side edges
137a and 137b may be creased or attached, or both creased and
attached, in order to prevent their unfoldment.
[0075] An exemplary form of a non-rectangular configuration of the
chassis is shown in FIG. 17. As shown in this figure, 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
be left 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 FIG. 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 155 and the respective side
edges 137 may be left laid out flat, i.e., may remain unfolded.
Similarly, 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 155 and the respective side edges 137 may be left laid
out flat, i.e., may remain unfolded. Other portions extending
longitudinally between the portions that remain unfolded and
through the crotch region 37 may be folded laterally inward to form
the side flaps 147. The portions 106 and the portions 108 form
"ears" that project laterally outward from each of the waist
regions of the diaper. These ears project laterally outward beyond
the inward-folded portions and impart an "I" shape to the diaper,
as shown in FIG. 17. It is not necessary that portions remain
unfolded at both ends as shown in FIG. 17. For example, the
portions 106 in the front waist region 36 may remain unfolded and
only the portions 108 in the back waist region 38 may be folded
laterally inward, or vice versa, in some embodiments.
[0076] An alternative way to form an "I"-shaped non-rectangular
configuration of the chassis as shown in FIG. 17 is to form the
chassis in the "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 137 of the chassis 100 to form the
respective side flaps 147. In embodiments in which the side flaps
are formed by attaching an additional layer or layers to the
chassis, each of the additional layer or layers may be attached at
or adjacent to its laterally distal edge.
[0077] Another exemplary way to form a non-rectangular
configuration of the chassis is shown in FIG. 18 and FIG. 19. As
shown in these figures, laterally opposing portions 107a and 107b
of the chassis between each of the side edges 137 and the
respective proximal edges 157 of the side flaps 147 may be folded
laterally inward in the crotch region 37 along respective diagonal
fold lines 105a, 105b, 105c, and 105d such that each of the folded
portions 107 of the chassis overlaps the absorbent assembly 200 in
the crotch region 37. The interior surface 102 of each of the
folded portions 107 may be attached to the interior surface 202 of
the absorbent assembly in the crotch region 37 at attachment zones
109a and 109b. This folding and attachment forms "W" shaped folds
112a and 112b in the chassis in the crotch region 37 as shown in
FIG. 19, while retaining the configuration of the waist regions 36
and 38 as shown in FIG. 3 and FIG. 6. The overall effect on the
shape of the chassis is to form an hourglass-shaped configuration
as shown in FIG. 18. The attachment zones 109 may be disposed
symmetrically with respect to either or both of the longitudinal
axis 42 and the lateral axis 44. Alternatively, the attachment
zones 109 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 FIG. 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 FIG. 1 are disposed
asymmetrically toward the front waist region 36.
[0078] 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, in order 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 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 109b. This folding and attachment forms
"W" shaped folds 112a and 112b in the chassis as shown in FIG. 19
over the entire longitudinal lengths of the laterally opposing
portions 107a and 107b of the chassis. An hourglass shape may
subsequently be imparted to the chassis when the laterally opposing
portions are laterally extended by unfolding at their
longitudinally distal ends to prepare the disposable diaper for use
in the configuration shown in FIG. 18.
[0079] A portion or the whole of the 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. 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 allow the 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 predefined range,
i.e., to tailor the diaper to the individual wearer. Such extension
of the waist region or regions 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 or regions, and may
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 would otherwise be sufficient only to make a relatively
smaller diaper lacking this extensibility can be used to make a
diaper capable of being extended to fit a wearer larger 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 fit onto a given size of a wearer when the material is
made extensible as described. The portion of the chassis in one of
the waist regions may be made laterally extensible to a maximum
extensibility greater than a maximum extensibility of another
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.
[0080] Additional extensibility in the chassis 100 in the lateral
direction is relatively more useful than additional extensibility
in the longitudinal direction because the abdomen of the wearer is
likely to expand when the wearer changes posture from standing to
sitting and the corresponding abdominal expansion increases the
circumference that is encircled by the waist edges of the chassis
100, necessitating the lateral extension of the waist region or
regions.
[0081] Additional lateral extensibility in the chassis 100 may be
provided in a variety of ways. For example, a material or materials
from which the chassis 100 is made may be pleated by any of many
known methods. Alternatively, all or a portion of the chassis may
be made of a formed web material or a formed laminate of web
materials like those described in U.S. Pat. No. 5,518,801 issued on
21 May 1996 in the name of Chappell et al. An exemplary fragment
300 of such a formed web material 305 is shown in FIG. 20. This
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 create a pattern of
generally longitudinally oriented alternating ridges 312 and
valleys 314. The formed web material 305 also includes laterally
extending unaltered regions 316 located between the laterally
extending altered regions 310.
[0082] The front laterally central portion 117 and the back
laterally central portion 118 of the chassis 100 between the
attachment zones 153 and 154 may have a different range of
extensibility from 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 easily or less easily 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 double layering in
the areas of the attachment zones after the formation of the side
flaps may have an effect of decreasing 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 a lesser degree than the altered regions
in the attachment zones to render the laterally central portions
more easily or less easily extensible than the respective portions
in the attachment zones.
[0083] 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 in many well-known ways. For example, separate fastening
devices such as safety pins, separate tapes, a separate tie strap
or straps, and/or a separate belt can be used for this purpose.
Alternatively or in addition, fastening elements can 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, adhesive tape tabs, ties, buttons,
hooks, loops, snap fasteners, other forms of mechanical fasteners,
cohesive patches, etc. 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.
[0084] For example, as shown in FIG. 21, 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 FIG. 21 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 FIG. 21 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 adhesive tapes are available from
the 3M Corporation of St. Paul, Minn., U.S.A., under the
designation of XMF99121. Suitable configurations of adhesive tape
tabs are disclosed in U.S. patent application Ser. No. 10/770,043
filed on 2 Feb. 2004.
[0085] When a laminate center sheet is used and is oriented with
the nonwoven disposed exteriorly, some forms of mechanical
fasteners that typically require specific mating fastener elements,
such as hooks that mate with loops, may be configured to engage
with the nonwoven and thereby make the inclusion of the specific
mating fastener element unnecessary. Alternatively, when a nonwoven
material is used to form the side flaps, a mechanical fastener such
as the aforementioned hooks may be positioned on the exterior
surface of the front waist region, such that when the back waist
region of the diaper is brought into an overlapping configuration
with the front waist region, the hook material engages the nonwoven
material of the side flap.
[0086] Optionally, a fastening sheet 116 may be attached onto the
exterior surface 104 of the chassis 100 in the front waist region
36 as shown in FIG. 21. The fastening sheet 116, shown in FIG. 21
lies entirely inside the edges of the diaper 20. Alternatively, two
or more discrete fastening sheets may be attached onto the exterior
surface of the chassis, instead of a single fastening sheet. For
example, two laterally opposing fastening sheets may be attached in
locations approximately corresponding to the left and right
portions of the 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 formed of a material used
elsewhere in the diaper, such as a film or a nonwoven. In
embodiments in which the chassis is extensible, it is preferred
that any fastening sheet also be extensible such that the fastening
sheet will not restrict the extensibility of the portion of the
chassis onto which it is attached. For example, an extensible
nonwoven may be used for the fastening sheet.
[0087] The fastening sheet serves to distribute the tensile force
transmitted by each of the adhesive tape tabs over an area of the
center sheet 26 that is larger than the adhered area of the
adhesive tape tab. In addition, when a single fastening sheet such
as fastening sheet 116 in FIG. 21 is used, the fastening sheet may,
itself, bear a portion of the tensile force between the laterally
opposing adhesive tape tabs and thereby relieve a portion of the
force exerted on the center sheet. Thus, the incorporation of such
a fastening sheet may be desirable, for example, in order to make
it possible to use a relatively inexpensive and relatively weak
material for the center sheet 26. The fastening sheet may be formed
of a material having greater strength than the center sheet. Such a
stronger material may be more expensive per unit area than the
center sheet, but the fastening sheet may be relatively smaller
than the center sheet. Therefore, the total cost of a diaper having
a fastening sheet may be less than the total cost of a diaper
having a center sheet having sufficient strength for adhesive tape
tabs to be adhered directly to the exterior surface of the center
sheet.
[0088] As another example, cohesive fastening elements may be used.
Exemplary fastening elements in the form of cohesive fastening
patches, such as the patches 110 and 120 shown in FIG. 1, FIG. 2,
FIG. 3, and FIG. 6 may be formed of an inherently crystalline
water-based synthetic elastomer to which a tackifying agent has
been added to disrupt the polycrystalline structure and thereby
render the elastomer cohesive. Such synthetic cohesive products are
available from Andover Coated Products, Incorporated, of Salisbury,
Mass., U.S.A. and are described in U.S. Pat. No. 6,156,424 issued
on 5 Dec. 2000 in the name of Taylor. Cohesive fastening patches
may be disposed on the exterior and/or interior surfaces of the
chassis in arrangements that allow exclusively for either
back-over-front fastening or front-over-back fastening of the waist
regions together. Alternatively, the cohesive fastening patches may
be disposed in a reversible configuration that is adapted to
provide the user of the diaper with both options for fastening,
i.e., either back-over-front or front-over-back, in the same
diaper, according to personal preference. Suitable configurations
of cohesive fastening elements are disclosed in U.S. patent
application Ser. No. 10/770,043 filed on 2 Feb. 2004.
Description of the Absorbent Assembly
[0089] As shown in FIG. 22, FIG. 23, and FIG. 24, the absorbent
assembly 200 includes an absorbent core 250 that serves to absorb
and retain liquid bodily waste materials. The absorbent core 250
has a laterally extending front edge 256 and a longitudinally
opposing and laterally extending back edge 258. 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. The absorbent
core 250 also has an interior surface 252 and an exterior surface
254.
[0090] The absorbent assembly 200 may be attached to the chassis
100 over any part or the whole of the area of the absorbent
assembly 200. Preferably, the absorbent assembly 200 is attached on
its exterior surface 204 to the chassis 100 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
detached portions and thereby lack contiguity 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.
[0091] An exemplary contiguous cruciform attachment pattern 210 is
shown in FIG. 22, FIG. 23, and FIG. 24. 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. 24 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. 22 and FIG. 23
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 and positioning 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 absorbent assembly was attached
only along the longitudinal centerline, the absorbent assembly
could be compressed by the legs to a smaller lateral dimension than
desired. This narrowing of the absorbent assembly would in turn
allow the chassis 100 in the crotch region 37 to narrow, i.e.,
allow the left side edge 137a and/or the right side edge 137b to
move toward the longitudinal axis 42. Such narrowing of the chassis
100 would increase the likelihood that the side flaps 147a and 147b
would distort and fail to maintain contact with the body and/or
become improperly positioned. 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 147 are more likely
to remain properly positioned while being lifted by the elastic
strands 167.
[0092] 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 film of an adhesive
may be applied continuously over the entire area of the cruciform
attachment pattern and then used to continuously attach the
absorbent assembly 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 used to attach the
absorbent assembly to the chassis.
[0093] 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. In addition, the cruciform attachment pattern 210
may be disposed symmetrically with respect to either or both of the
side edges 237 and the front edge 236 and the back edge 238 of the
absorbent assembly 200. Alternatively, the cruciform attachment
pattern 210 may be disposed asymmetrically with respect to either
or both of the side edges 237 and front edge 236 and back edge
238.
[0094] Suitable configurations of cruciform attachment patterns are
disclosed in U.S. patent application Ser. No. 10/880,128 filed on
29 Jun. 2004.
[0095] The absorbent core 250 may be disposed between a lower
covering sheet that is disposed on the exterior face of the
absorbent core 250 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 FIG. 22, FIG. 23, and FIG. 24, an upper covering sheet 24
and a lower covering sheet 25 are attached together at or adjacent
to the side edges 237 of the absorbent assembly 200 in
longitudinally extending adhesive attachment zones 29a and 29b.
Alternatively, the upper covering sheet 24 and the lower covering
sheet 25 may be attached together in places other than the side
edges 237, e.g., 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 237. Both the upper covering sheet and
the lower covering sheet are water vapor-permeable, i.e.,
breathable.
[0096] The upper covering sheet 24 is water-permeable and allows
liquid waste to pass through to the absorbent core 250, where the
liquid waste is absorbed. The lower covering sheet 25 may be
water-impermeable. However, the lower covering sheet 25 preferably
is 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 an 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.
[0097] 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
preferably is formed of a soft material that will not irritate the
skin of the wearer. Many materials that are suitable for a
water-permeable covering sheet are well-known in the art, including
synthetic nonwovens such as spunbonded or carded polypropylene,
polyester, or rayon. Likewise, many materials that are suitable for
a covering sheet that is water-impermeable are well-known in the
art, including the materials that are suitable for the center sheet
26.
[0098] 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 respective 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 adjacent waist edge. Such
an extended covering sheet may serve to isolate the skin of the
wearer from a portion of the center sheet 26 as may be desirable,
for example, when the diaper 20 is worn under conditions in which
contact between the skin and a center sheet film could be
uncomfortable.
[0099] In the exemplary absorbent assembly 200 shown in FIG. 22,
FIG. 23, and FIG. 24, 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 both side edges 237
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 257 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
description of the separate upper covering sheet 24 and lower
covering sheet 25 are intended to apply to such upper and lower
layers of a wrapped single covering sheet.
[0100] The absorbent core 250 includes a storage component that
serves to absorb and retain liquid bodily waste materials. Suitable
known materials for the absorbent core storage component include
cellulose fibers in the form of comminuted wood pulp, commonly
known as "airfelt", natural or synthetic fibrous materials, and
superabsorbent polymers, used either singly or in mixtures and
commonly formed into layers or sheets, etc. These absorbent
materials may be used separately or in combination. Many known
absorbent materials may be used in a discrete form, i.e., in the
form of fibers, granules, particles, and the like. Such a discrete
form of an absorbent material may be immobilized by an adhesive
that attaches the discrete pieces together to form a coherent layer
or that attaches the discrete pieces to a substrate layer or that
attaches the discrete pieces both to each other and to the
substrate layer.
[0101] The absorbent core may include an acquisition component in
addition to one or more storage components. The absorbent core
acquisition component serves to acquire deposited liquid bodily
waste material and transfer it to the absorbent core storage
component. Any porous absorbent material which will imbibe and
partition liquid bodily waste material to the storage component or
components may be used to form the acquisition component. Preferred
materials for the acquisition component include synthetic fiber
materials, open celled polymeric foam materials, fibrous nonwoven
materials, cellulosic nonwoven materials, and various combination
synthetic/cellulosic nonwoven materials. For example, the
acquisition component may be formed of a nonwoven web or webs of
synthetic fibers including polyester, polypropylene, and/or
polyethylene, natural fibers including cotton and/or cellulose,
blends of such fibers, or any equivalent materials or combinations
of materials. Examples of such acquisition materials are more fully
described in U.S. Pat. No. 4,950,264 issued to Osborn on Aug. 21,
1990. High loft nonwoven acquisition materials suitable for the
acquisition component of the present invention can be obtained from
Polymer Group, Inc., (PGI), 450 N.E. Blvd, Landisville, N.J. 08326,
U.S.A., under the material code designation of 98920.
[0102] Such an absorbent core 250 including an acquisition
component 290 overlying an absorbent core storage component 272 is
shown in FIG. 25. A separation sheet 292 of, e.g., a tissue or a
nonwoven material, may be disposed between the absorbent core
storage component 272 and the absorbent core acquisition component
290 to help ensure that none of the gel formed by a superabsorbent
polymer that may be included in the absorbent core storage
component reaches the skin of the wearer. This separation sheet 292
may extend laterally beyond the side edges 257a and 257b of the
absorbent core 250 and the upper covering sheet 24 may be attached
to the separation sheet 292. In this arrangement, the liquid bodily
waste material that is deposited onto the upper covering sheet 24
will pass through the thickness of the upper covering sheet 24 to
be absorbed by the absorbent core acquisition component 290, and
some or all of it may then pass through the thickness of the
separation sheet 292 and then be absorbed and retained by the
absorbent core storage component 272.
[0103] In some exemplary embodiments, an absorbent core storage
component may include the discrete form of an absorbent material
that is immobilized in pockets formed by a layer of a thermoplastic
material, such as a hot melt adhesive, that intermittently contacts
and adheres to a substrate sheet, while diverging away from the
substrate sheet at the pockets. Absorbent core components having
such structures and being suitable for the storage of liquid bodily
wastes are described in U.S. patent applications Ser. Nos.
10/776,839 and 10/776,851, both filed on 11 Feb. 2004 in the name
of Ehrnsperger et al. An exemplary absorbent core storage component
272 having such a structure is shown in FIG. 26. In this absorbent
core storage component 272, particles 270 of a superabsorbent
polymer are contained inside pockets 280 formed by a layer 275 of a
thermoplastic material. The absorbent core storage component may
include both particles of superabsorbent polymer and airfelt and
both materials may be contained inside the pockets formed by the
layer of the thermoplastic material. Alternatively as shown in FIG.
26, an exemplary absorbent core storage component may contain no
airfelt and therefore the component can be made relatively thinner
and more flexible for the comfort of the wearer. In addition, the
particles of the superabsorbent polymer can be immobilized
relatively more easily in the absence of airfelt. As shown in FIG.
26, the layer 275 of the thermoplastic material intermittently
contacts and adheres to a substrate sheet 274 at the areas of
attachment 282. Between the areas of attachment 282, the layer 275
diverges away from the substrate sheet 274 to form the pockets 280.
The layer 275 may have the form of a sheet of fibers of the
thermoplastic material through which the liquid waste may pass to
the particles to be absorbed by the particles 270 of the
superabsorbent polymer.
[0104] In FIG. 26, a separate thermoplastic layer covering sheet
276 is shown overlying the layer 275 of the thermoplastic material.
Alternatively, the separate thermoplastic layer covering sheet 276
may be omitted. As another alternative, two absorbent core storage
components each like that shown in FIG. 26 except for the omission
of the thermoplastic layer covering sheet 276 may be superposed
with one absorbent core storage component inverted such that the
respective substrate sheets distally oppose each other. In such a
combination of absorbent core storage components, either or both of
the distally opposing substrate sheets may serve respectively as
either or both of an upper covering sheet and a lower covering
sheet for the absorbent assembly. Alternatively, the absorbent
assembly may include a separate lower covering sheet and/or a
separate upper covering sheet.
Statements of Incorporation by Reference and Intended Scope of
Claims
[0105] The disclosures of 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 description, are hereby incorporated herein by
reference. It is expressly not admitted that any of the documents
or any combination of the documents incorporated herein by
reference teaches or discloses the present invention.
[0106] 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. Further, it should be apparent that all
combinations of such embodiments and features are possible and can
result in preferred executions of the invention. Therefore, the
appended claims are intended to cover all such changes and
modifications that are within the scope of this invention.
* * * * *