Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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ABSORBENT ARTICLES WITH FEEDBACK SIGNAL UPON URINATION
FIELD OF THE INVENTION
The present disclosure generally relates to absorbent articles, including
diapers, training pants, pull-on diapers, inserts, diaper holders and liners,
and the like,
and in particular to an absorbent article with a feedback sensory element
member,
which may be adapted for use in urinary toilet training.
BACKGROUND OF THE INVENTION
Absorbent articles are well known in the art. These articles typically have an
absorbent assembly held or positioned in proximity to the body of a wearer
during use
in order to capture and absorb bodily exudates discharged from the wearer.
Typical
absorbent articles include a topsheet facing the wearer, which permits fluid
exudates
to pass through, and an outer cover, which prevents the exudates from escaping
from
the absorbent article.
The toilet training stage may be referred to as the "point of exit" from the
diaper product category because toddlers who have successfully completed
toilet
training typically no longer wear diapers. The age at which children are
toilet trained
in "developed" countries has increased steadily over the past several decades
and is
now in the range of about 24-48 months. One reason for which toilet training
has
become delayed is that significant technical improvements have been made in
diaper
dryness and comfort. For example, when wearing a typical modem diaper, the
child
may have dry skin even after one or more occurrences of urination. As a
result, the
child may feel little or no discomfort and often may not even be aware that he
or she
has urinated.
Some parents may have the child wear cotton training pants or cotton
underwear during urinary training so the child feels discomfort following
urination in
his or her "pants." It is believed that such discomfort assists with learning
or provides
motivation to learn to voluntarily retain urine (at least until the child can
urinate in a
socially acceptable time/location). Cloth training pants leave the skin wet
and, due to
their high breathability, promote evaporative cooling of the skin, further
enhancing
discomfort. The current tradeoff in this approach, however, is that cloth
training pants
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have poor urine containment, often leading to wet clothing and wet
surroundings, e.g.,
carpeting, furniture, etc. There is a need to provide disposable absorbent
articles
where the article itself has features which facilitate toilet training without
compromising the convenience of the disposable product form.
Several attempts have been made in the prior art to provide disposable
absorbent articles which provide some sort of feedback such as a "coolness" or
"wetness" signal to alert the wearer of the incidence of urination. Examples
of such
approaches have included garments which provide a "feel wet" signal. U.S.
Patent
6,958,432 discloses an example of a garment with a member which attempts to
provide such a feeling of wetness. U.S. Patent 6,642,427 discloses a garment
which
contains endothermic salts and similar substances to provide a temperature
change or
feeling of coolness. U.S. Patent 5,797,892 discloses an article which attempts
to
change size or shape upon urination to provide a tactile feedback to the
wearer upon
urination.
These approaches found in the prior art have met with some commercial
success and accomplish the training objective at least to some degree. It has
been
found during development of the present invention that several - sometimes
contradictory - characteristics of feedback mechanisms are important. For
example,
it has been found during development of the present invention that an ideal
feedback
mechanism should provide a nearly immediate response upon urination. If the
response time for the signal is too long, the child may not properly associate
the signal
with the urination event which triggered it. It has also been found during
development of the present invention that the feedback mechanism should
ideally also
provide a temporary signal. The temporary duration of the signal helps to
reinforce
the association with the urination event. In other words, if the signal lasts
too long or
indefinitely the wearer may become undesirably accustomed to the signal.
Additionally, a signal which persists may lead to undesirable impacts such as
stress
on the wearer's skin.
Another characteristic of well designed feedback mechanisms discovered
during development of the present invention is that such mechanisms should be
harmless to the wearer and the wearer's skin. For example, a feedback
mechanism
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which provided prolonged contact of a urine saturated component with the skin
could
lead to skin irritation and, therefore, would not be ideal.
It has also been found during development of the present invention that ideal
feedback mechanisms be unmistakable to the wearer. For example, if the signal
provided to the wearer were too subtle or ambiguous the training benefit of
the signal
may not be effectively achieved.
Consequently, a need, therefore, exists for disposable absorbent articles and
garments which provide urination feedback mechanisms which are as immediate
and
unmistakable to the wearer as possible. Such feedback mechanisms should also
be
temporary and harmless. It would desirable to provide an article that can
facilitate
urinary toilet training by enhancing a wearer's awareness that urination has
occurred
by providing such a signal to the wearer while at the same time providing the
protection of an absorbent article to prevent soiling of the wearer's clothing
and
surroundings.
SUMMARY OF THE INVENTION
In one aspect of the invention an absorbent article for wearing about the
lower
torso of a wearer said absorbent article includes a first waist region, a
second waist
region disposed opposite the first waist region, and a crotch region
connecting said
first waist region and said second waist region. The article also includes an
absorbent
core disposed between the outer cover and the topsheet. Additionally, the
article also
includes a sensory element member at least partially disposed in the crotch
region of
said absorbent article. The sensory element member provides a feedback
response to
the wearer upon a urination event. This feedback response occurs within about
60
seconds of said urination event and persists no longer than about 10 minutes
beyond
said urination event. The sensory element member includes a body contacting
portion
having an area of at least about 25 cm2.
The feedback response may occur within about 30 seconds of said urination
event or within about 15 seconds of said urination event. The feedback
response may
persist no longer about 600 seconds, or about 300 seconds, or about 150
seconds. The
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area of the body contact portion may be at least about 50 cm2, or at least
about 100
cm2, or at least about 200 cm2.
The feedback response provided by said sensory element member may be
selected from the group consisting of elements providing a wetness sensation,
a
temperature change sensation, a coolness sensation, and combinations thereof.
The
body contacting portion of the sensory element member may include a skin
protecting
feature selected from the group consisting of a pH buffer material, Zinc
Oxide,
enzyme inhibitors, skin care compositions and combinations thereof. The
article may
be a disposable diaper or a pant-like garment. Pant-like garment
configurations may
include a refastenable fastening member. Such refastenable fastening member
may
include an adhesive or cohesive based fastening system, a tab and slot type
mechanical fastener or a hook and loop type mechanical fastener. A pant-like
garment of the present invention may comprise an easy open feature.
The article may include active graphics including at least one disappearing
graphic or at least one appearing graphic. The outer cover of the article may
include
at least a portion which is water impermeable, breathable, and water vapor
permeable.
The article may also include a second sensory element member which
provides an audible feedback response upon a urination event. The sensory
element
may be at least partially separable from said topsheet. The sensory element
member
may be elastically foreshortened along at least a portion of the length of the
topsheet.
The body contacting portion of the sensory element may be enhanced via a
contact
promoting agent. The article may include a pair of barrier cuffs wherein the
sensory
element member is associated with said barrier cuffs.
In another aspect of the invention, an absorbent article for wearing about the
lower torso of a wearer said absorbent article includes a first waist region,
a second
waist region disposed opposite the first waist region, and a crotch region
connecting
said front waist region and said rear waist region. The article also includes
an outer
cover, a water-permeable topsheet attached to the outer cover and having a
body-
facing surface and an absorbent core disposed between the outer cover and the
topsheet. The article includes a wetness sensation member at least partially
disposed
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in the crotch region of the absorbent article. The wetness sensation member
provides
a wetness indication to the wearer upon a urination event. The wetness
sensation
member has a body contacting portion which has a first Moisture Density of at
least
about 2 mg/cm2 at 60 seconds after the urination event and a second Moisture
Density
5 at 10 minutes after said urination event of less than about 80% of the first
Moisture
Density.
The first Moisture Density may be at least about 4 mg/cm2 or at least about 5
gm/cm2at 60 seconds after said urination event. The second Moisture Density at
10
minutes after said urination event may be less than about 75 % or less than
about 70 %
of the first Moisture Density.
The absorbent article of may also include a temperature sensation member at
least partially disposed in the crotch region of the absorbent article. Such
temperature
sensation member may provide a temperature change sensation to the wearer upon
a
urination event. The temperature change sensation may occur within about 30
seconds of the urination event and persist no longer than about 300 seconds
beyond
the urination event. The temperature change sensation member may provide a
surface
temperature change of from about 5 C to about 20 C at 30 seconds after the
urination
event.
The wetness sensation member may include body contacting portion having an
area of at least about 25 cm2 or of at least about 100 cm2.
The article may be a disposable pant-like garment. Such a disposable pant like
garment may include a refastenable fastening member or may include an easy
open
feature. The article may include active graphics disposed on at least a
portion of the
article. The outer cover may include a portion which is water impermeable,
breathable and water vapor permeable.
In another aspect of the invention, an absorbent article for wearing about the
lower torso of a wearer said absorbent article includes a front waist region,
a rear
waist region disposed opposite the front waist region, and a crotch region
connecting
the front waist region and the rear waist region. The article also includes an
outer
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cover, a water-permeable topsheet attached to the outer cover and having a
body-
facing surface. The article includes an absorbent core disposed between the
outer
cover and the topsheet. The article also includes a temperature change member
at
least partially disposed in the crotch region of the absorbent article. The
temperature
change member provides a temperature change to the wearer upon a urination
event.
The temperature change occurs within about 30 seconds of the urination event
and
persists no longer than about 300 seconds beyond the urination event. The
temperature change member provides a surface temperature change of from about
5 C
to about 20 C at 30 seconds after the urination event.
The absorbent article may further include a wetness sensation member at least
partially disposed in the crotch region of the absorbent article. The wetness
sensation
member may provide a wetness indication to the wearer upon a urination event.
The
wetness sensation member may have a body contacting portion which has a first
Moisture Density of at least about 2 mg/cm2 at 60 seconds after the urination
event
and a second Moisture Density at 10 minutes after the urination event of less
than
about 80 % of said first Moisture Density.
The temperature change may occur within about 15 seconds or within about
10 seconds of the urination event. The temperature change may persist no
longer than
about 150 seconds. The temperature change member may include a body contacting
portion having an area of at least about 25 cm2 or at least about 100 cm2. The
article
may be a disposable pant-like garment. Such a disposable pant like garment may
include a refastenable fastening member or an easy open feature. The article
may
include active graphics disposed on at least a portion of the article. The
outer cover
may include a portion which is water impermeable, breathable and water vapor
permeable.
In another aspect of the invention an absorbent article for wearing about the
lower torso of a wearer said absorbent article includes a front waist region,
a rear
waist region disposed opposite the front waist region, and a crotch region
connecting
the front waist region and the rear waist region. The article also includes an
outer
cover, a water-permeable topsheet attached to the outer cover and having a
body-
facing surface. The article includes an absorbent core disposed between the
outer
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cover and the topsheet. The article also includes a temperature change member
at
least partially disposed in the crotch region of the absorbent article. The
temperature
change member provides a temperature change upon a urination event. The
temperature change occurs at a rate of at least about 1 C/sec within the first
2 minutes
following the urination event.
The temperature change may occur at a rate of at least 2 C/sec within the
first
20 seconds or within the first 5 seconds following the urination event. The
temperature change may occur at a rate of at least 3 C/sec within the first 20
seconds
or within the first 5 seconds following the urination event. The temperature
change
may occur at a rate of at least 5 C/sec within the first 20 seconds or within
the first 5
seconds following the urination event.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and
distinctly claiming the subject matter that is regarded as the present
invention, it is
believed that the invention will be more fully understood from the following
description taken in conjunction with the accompanying drawings. 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. None of the drawings are
necessarily to scale.
Fig. 1 is a plan view of an absorbent article with a section of a topsheet
removed to expose an underlying absorbent core;
Fig. 2a is a perspective view of an exemplary absorbent article shown in its
relaxed, contracted state, i.e., with the contraction induced by elastic
members
approximating its in use configuration;
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Fig. 2b is a perspective view similar to Fig. 2a showing an article having
easy
open side seam features;
Fig. 3a is a plan view of an absorbent article having a sensory element
member according to an embodiment of the present disclosure;
Fig. 3b is a cross-sectional view of the article shown in Fig. 3a illustrating
the
layers of the sensory element member;
Fig. 4a is an isometric view of the article shown in Fig. 3a illustrating a
first
exemplary attachment of the sensory element member;
Fig. 4b is an isometric view of the article shown in Fig. 3a illustrating a
second exemplary attachment of the sensory element member;
Fig. 5a is a plan view of an absorbent article having a sensory element
according to another embodiment of the present disclosure;
Fig. 5b is a cross-sectional view of the article shown in Fig. 5a illustrating
the
layers of the sensory element member;
Fig. 6a is a plan view of an absorbent article having a sensory element
member according to a further embodiment of the present disclosure;
Fig. 6b is a cross-sectional view of the article shown in Fig. 6a illustrating
the
layers of the sensory element member.
Figs. 7a-7c are cross-sectional views of another embodiment of an absorbent
article.
Fig. 8 is a cross-sectional view of a preferred embodiment of the absorbent
core.
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DETAILED DESCRIPTION OF THE INVENTION
DEFINITIONS
As used herein, 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 "associated with", in relation to highlighting, refers at least to
highlighting that is on an element or to highlighting that is disposed
proximate to an
element.
The term "associative correlation" refers to establishing a mutual or
reciprocal
relation between the visible highlighting and that with which it is being
associatively
correlated so that an association, i.e. a mental connection or bond, is formed
between
the two. This term is used in the context of associatively correlating the
respective
visible forms of the visible highlighting and an externally visible graphics
in or on the
absorbent article as well as in the context of associatively correlating the
visible
highlighting or graphics with the concept of urinary toilet training, For
example,
associatively correlated graphics may serve in concert to draw attention to an
opportunity for urinary toilet training when an absorbent article is viewed
prior to its
being worn, to provide an externally visible reminder of the presence of the
sensory
element member in the interior of the absorbent article while it is being
worn, etc.
Similarly, visible highlighting that provides a visual reference to a topic
related to
urinary toilet training, such as dryness, wetness, or protection from wetness,
may
serve to associatively correlate the visible highlighting to the concept of
urinary toilet
training and thereby facilitate an opportunity for urinary toilet training.
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,
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thermal bonding, mechanical fastening, etc. Such attachment methods may be
used to
attach elements together over a particular area either continuously or
intermittently.
The term "caregiver" refers to a person other than the child, such as, a
parent,
babysitter, family member, teacher, day care worker, or other person who is
able to
5 provide sufficient assistance to the child to complete a personal hygiene
task.
The term "character image" refers to a graphic containing an anthropomorphic
image, and in particular an image having or suggesting human form or
appearance
which ascribes human motivations, characteristics or behavior to inanimate
objects,
animals, natural phenomena, toys, cartoon characters, or the like. The
character image
10 may be associated with popular characters in the media, advertising or well
known in
a particular culture. Ideally they are characters that the user, particularly
if a child,
cares about and wants to identify with.
The term "coloration" refers to the arrangement or degree of coloring
especially when used to visibly differentiate an object or a portion of an
object in
order to visibly highlight it.
The term "coloring" refers to the effect produced by applying or combining
colors in and/or on an object or a portion of an object.
The term "diaper" refers to an absorbent article generally worn by infants,
children, and/or incontinent persons about the lower torso and having the
general
form of a sheet, different portions of which are fastened together to encircle
the waist
and the legs of the wearer.
The term "disposable" refers to absorbent articles that generally are not
intended to be laundered or otherwise restored or reused as absorbent
articles, 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 "disposed" is used to mean that an element(s) is formed (joined and
positioned) in a particular place or position as a unitary structure with
other elements
or as a separate element joined to another element.
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The term "graphic" refers to a product of graphic art or a graphic
representation in a pictorial form. A graphic may be a symbol, shape, image,
text, or
other form of indicia.
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" and "top" and "bottom", respectively.
The term "lateral" or "transverse" refers to a direction running at a 90
degree
angle to the longitudinal direction and includes directions within 45 of
the lateral
direction.
The term "longitudinal" refers to a direction running parallel to the maximum
linear dimension of the article and includes directions within i45 of the
longitudinal
direction.
The terms "pre-literate" and "incapable of reading" are used interchangeably
herein to mean the inability of a child to correctly understand, comprehend
and follow
prompts written in a language that the child can speak without assistance of a
caregiver. The ability of a child to recognize letters and/or read one or two
isolated
words still means that the child is "incapable of reading" since he or she is
unable to
understand, comprehend and follow such written prompts, without assistance.
However, this definition of "incapable of reading" does not exclude the child
from
being able to understand, comprehend and follow visual prompts which are
presented
in the form of drawings, icons, symbols, gestures, cartoons and the like.
The term "refastenable" refers to the property of two elements being capable
of releasable attachment, separation, and subsequent releasable reattachment
without
substantial permanent deformation or rupture.
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The terms "releasably attached," "releasably engaged," and variations thereof
refer to two elements being connected or connectable such that the elements
tend to
remain connected absent a separation force applied to one or both of the
elements, and
the elements being capable of separation without substantial permanent
deformation
or rupture. The required separation force is typically beyond that encountered
while
wearing the absorbent garment.
The term "solid coloring" refers to the unbroken, i.e., uninterrupted,
coloring
of an area as contrasted with the discrete line-like form of some graphics.
The term "toilet training" refers to the development of continence, which is
the ability to voluntarily retain one's urine and feces. Individuals who are
incontinent
are unable to voluntarily retain their bodily discharges and, instead, urinate
and
defecate reflexively. For example, newborn babies are incontinent. Coincident
with
the development of continence, children typically develop the ability to
voluntarily
urinate and defecate, and cease reflexive elimination. This development of
continence and of voluntary elimination, in place of reflexive elimination,
may be
accelerated and/or guided by caregivers through associative and conditioning
techniques of training the child. For the purpose of the present disclosure,
the term
"toilet training" is used to denote training both for continence, itself, and
for the
voluntary elimination that is associated with continence. It is also noted
that the term
"toilet training" is synonymous with the term "potty training".
The terms "training pants," or "pant-like garments" refer to an absorbent
article generally worn by infants and incontinent persons about the lower
torso and
having the general form of a pair of short pants that can be applied or
removed from
the wearer without unfastening.
The term "unitary" refers to an absorbent article that is formed of separate
parts united together to form a coordinated entity so as to not require
separate
manipulative parts like a separate holder and liner.
The term "visible" refers to the quality of being capable of being seen by the
naked eye under conditions of normal room lighting or in natural light during
the
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daytime. Becoming "more visible" or "less visible" means changing in
visibility to a
noticeable extent when viewed under a generally constant or equal lighting
condition.
The term "visible highlighting" refers to the visible differentiation of an
object
such that it noticeably stands out from its surroundings, e.g., by differing
in
coloration, hue, or tint, by differing in lightness, darkness, or contrast, by
differing
due to the presence or absence of graphical or solid color forms, or by any
other
variation serving to create noticeable visible differentiation.
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).
The term "x-y plane" refers to the generally planar structure of a sheet
material defined by its length and width and lies between the sheet material's
two
major surfaces regardless of whether or not the sheet material is flat or
curved.
The term "z-direction" refers to the direction through the thickness of a
sheet
material and generally orthogonal to the x-y plane.
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The term "sensory element member" is analogous to "sensation member" and
"feedback response member" as used herein or in copending applications US
Publication Nos. 2007/0287971, 2007/0233025, 2007/0233027, 2007/0233028, and
2007/0233026 all filed on 3/31/2006.
DESCRIPTION
Fig. 1 is a plan view of an exemplary disposable absorbent article 20 in its
flat,
uncontracted state, i.e., without elastic-induced contraction. Portions of the
article 20
have been cut away to more clearly show the underlying structure of the
disposable
absorbent article 20. As illustrated, the portion of the disposable absorbent
article 20
that contacts the wearer faces the viewer (i.e., showing the interior or inner
side of the
article). The disposable absorbent article 20 has a longitudinal axis 30 and a
transverse axis 32.
One end portion of the disposable absorbent article 20 is configured as a
first
waist region 40 of the disposable absorbent article 20. The opposite end
portion is
configured as a second waist region 42 of the disposable absorbent article 20.
The
waist regions 40 and 42 generally comprise those portions of the disposable
absorbent
article 20 which, when worn, encircle the waist of the wearer. The waist
regions 40
and 42 may include elastic elements such that they gather about the waist of
the
wearer to provide improved fit and containment. An intermediate portion of the
disposable absorbent article 20 is configured as a crotch region 44, which
extends
longitudinally between the first and second waist regions 40 and 42. The
crotch
region 44 is that portion of the disposable absorbent article 20 which, when
the
disposable absorbent article 20 is worn, is generally positioned between the
legs of the
wearer.
The disposable absorbent article 20 has a laterally extending first waist edge
50 in the first waist region 40 and a longitudinally opposing and laterally
extending
second waist edge 52 in the second waist region 42. The disposable absorbent
article
20 has a first side edge 54 and a laterally opposing second side edge 56, both
side
edges extending longitudinally between the first waist edge 50 and the second
waist
edge 52. The portion of the first side edge 54 in the first waist region 40 is
designated
54a, the portion in the crotch region 44 is designated 54b, and the portion in
the
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second waist region 42 is designated 54c. The corresponding portions of the
second
side edge 56 are designated 56a, 56b, and 56c, respectively.
The disposable absorbent article 20 preferably comprises a water-permeable
topsheet 60, an at least partially water-impermeable outer cover 62, and an
absorbent
5 assembly or core 64, which may be disposed between the topsheet 60 and the
outer
cover 62 with the topsheet 60 attached to the outer cover 62. The topsheet 60
may be
fully or partially elasticized or may be foreshortened so as to provide a void
space
between the topsheet 60 and the core 64. As explained below, a fully or
partially
elasticized topsheet 60 may also to tend to draw a sensory element member
against
10 the skin of the wearer. Exemplary structures including elasticized or
foreshortened
topsheets are described in greater detail in U.S. Patent Nos. 4,892,536;
4,990,147;
5,037,416; and 5,269,775, among others.
Fig. 2a illustrates the article illustrated in Fig. 1 configured to as it
would be
wom. The disposable absorbent article 20 may be sealed at the sides so as to
be
15 configured as illustrated in Fig. 2a. However, the article 20 may instead
include
refastenable side seams 70 that can be used to fasten the waist regions 40, 42
together.
According to one exemplary embodiment, the waist regions 40, 42 may be
fastened at
the sides to apply the article like a diaper. According to a further exemplary
embodiment, illustrated in Fig. 2a, the side seams 70 may include fasteners 72
that
can be used to configure the article like a pair of pull-on training pants or
disposable
pants.
As illustrated, the fasteners 72 may be disposed on the interior of the
disposable absorbent article 20 in the second waist region 42 adjacent to the
portion
54c of the first side edge 54 and adjacent to the portion 56c of the second
side edge
56. The portion 54c of the side edge 54 is shown in an open condition, such as
prior
to closing and fastening or after being reopened. The portion 56c of the
opposing side
edge 56 is shown fastened, i.e., forming a pants configuration. In Fig. 2a,
the second
waist region 42 overlaps the first waist region 40 when they are fastened
together.
The fasteners 72 may be formed of any material and in any form that will
releasably attach to the mating surface of the opposing waist region when
pressed
CA 02583440 2007-03-30
16
against it. For example, the primary fastening component may be a mechanical
fastener that releasably engages with the mating surface, such as by means of
a
plurality of hooks engaging with loops formed by fibers in a nonwoven sheet.
Alternatively, the primary fastening component may be an adhesive, cohesive,
or
selective adhesive material that releasably adheres to the mating surface.
Still other variations are also possible. For example, the fasteners 72 may be
disposed on the interior of the article 20 in the first waist region 40 such
that the first
waist region 40 overlaps the second waist region 42 when they are fastened
together.
As another example, the fasteners 70 may be disposed on the exterior of the
article 20
rather than on the interior. As a further example, the fasteners 70 may be
used with a
specific mating fastener surface particularly suited for cooperation with the
fasteners
70 (e.g., a loop layer that works with a hook fastener, or a layer
particularly treated to
provide a suitable contacting surface for a specific adhesive). Additionally
exemplary
fasteners and fastener arrangements, the fastening components forming these
fasteners, and the materials that are suitable for forming fasteners are
described in
U.S. Published Application Nos. 2003/0060794 and 2005/0222546 and U.S. Patent
No. 6,428,526, among others. Other fastener types may include "tab and slot"
type
mechanical refastenable fasteners. Buttons, snaps, zippers, and other types of
fasteners, including refastenable fasteners are also possible.
It has been discovered during development of the present invention that the
development of dressing and undressing skills as well as the development of
continence are both related to and potentially important to a successful potty
training
experience. For example, a child may begin to recognize the urge to urinate
and have
an ability to control and delay the onset of urination. If such a child has a
desire to
use the toilet, but is wearing a disposable absorbent article which he or she
does not
have the dexterity to remove readily, the child may not be able to use the
toilet
successfully. Therefore, it may be desirable to provide "easy open" features,
such as
those described further below either with or without refastenability features
in a
garment in combination with the sensory elements described herein to provide a
garment having multiple potty training features in combination which
synergistically
re-enforce each other. Additionally, features which allow a child to more
easily lower
CA 02583440 2009-11-26
17
(or raise) the garment such as handles, printed indications of gripping
features or the
like such as those described in Publication Nos. 2006/0212010 and 2006/0212018
may also be included.
The disposable absorbent article 20 may be provided with an easy open feature
such as shown in Fig. 2b. Such an easy open feature can comprise a single
element or
a combination of elements designed to make the seams of the article easier to
open so
as to remove the article. For example the easy open feature could comprise a
gripping
tab 74. Additionally an easy open bond line pattern 76 could be provided
either alone
or in combination with the gripping tab 74. The easy open bond line pattern 76
shown in Fig. 2b can act as a type of "zipper" structure allowing propagation
of an
opening force along the side of the article 20. In some embodiments, the easy
open
bond line pattern may comprise indicia which indicate where to open the
article.
Such indicia are described in Publication No. 2007/0032766 filed on August 5,
2005
in the name of Liu et al. Other easy open features could include a line of
weakness, a
notch or tab designed to propagate a tear, a tab gripping area or similar
feature
designed to allow for more easy release of a refastenable side fastener. Easy
open
features such as those described above can be provided if desired on articles
having
refastenable features or those which do not have refastenable fasteners - for
example,
a pant like garment with pre-formed side seams incorporating an easy open
feature
which can be used once, but which does not allow for refastenability once
opened.
According to the present disclosure, the exemplary article 20, such as is
illustrated in Figs. I and 2a and 2b, may be combined with or assembled to
include a
sensory element member 80. Several embodiments, some with one or more
variations, are illustrated in Figs. 3a, 3b, 4a, 4b, 5a, 5b, 6a, and 6b.
Elements common
to all embodiments are numbered similarly in all Figures, while those elements
unique
to each embodiment are numbered differently, with the sensory element member
according to a first embodiment being numbered as 80, a second embodiment as
180,
and a third embodiment as 280. In addition, while the exemplary absorbent
articles
illustrated each include a single sensory element member, the articles may
include a
CA 02583440 2007-03-30
18
plurality of sensory element members either of the same type or of differing
types
according to other embodiments.
The sensory elements (incorporated into sensory element members) of the
present invention may provide a feedback response to the wearer upon a
urination
event by the wearer. The type of feedback provided may vary, but may include
by
way of example a wetness sensation response or a temperature response. A
temperature response could include one or both of an actual temperature change
produced in the article which is transmitted to the wearer's skin or a
sensation of
warmness or coolness produced without an actual temperature change (or at
least not
an actual temperature change as great as the perception of temperature
change).
Temperature change responses can include increases (i.e. warmness) or
decreases (i.e.
coolness) from the initial or "baseline" temperature prior to the onset of the
response.
For purposes of clarity, a response producing an actual increase or decrease
in
temperature in at least a portion of the article will be referred to herein as
a
"temperature change" or "cooling" or "warming." A response which produces only
a
sensation of warmness or coolness without an actual corresponding temperature
change will be referred to herein as a "warmness sensation" or "coolness
sensation."
The feedback response could include multiple sensations such as a
combination of wetness and cooling. Other tactile responses such as an
effervescent
"bubbling" response or an audible or visual response could also be provided.
Again,
such tactile, audible, or visual responses may be combined with each other as
desired.
For purposes of clarity "tactile" responses are taken to be those
corresponding to the
sense of touch or feel. These include temperature change, warmness and
coolness
sensation, and other physical interaction with the skin responses such as
bubbles,
physical protrusion of the article, tightness, or the like. "Tactile"
responses are
distinguished from those which rely on other senses such as hearing, vision,
or smell.
Tactile based sensory responses may be preferred to include in the article
because a wearer may more readily associate such tactile feedback mechanisms
with
the triggering urination event. In particular, it may be desired to provide a
temperature change response such as a cooling or a warming (or sensations of
either
or both) as the sensory feedback mechanism. It may be desirable to combine
such
CA 02583440 2007-03-30
19
wetness or temperature (or other) sensory feedback mechanisms with visual or
audible response mechanisms to allow participation in the toilet training
process by a
caregiver or for additional re-enforcement to the wearer. Any of the
mechanisms
(described in greater detail below) for providing a feedback response to a
wearer may
be incorporated into any of the embodiments described below for structurally
delivering the feedback. As noted previously, it is desirable that the
urination
triggered feedback responses provided by immediate, temporary, harmless, and
unmistakable. Accomplishing these objectives requires control of both the
manner in
which the signal itself is generated, as well as the manner in which the
signal is
transmitted to the wearer. The experience of the wearer of the feedback signal
will be
based upon a combination of the feedback characteristics (such as signal
intensity)
and transmission characteristics.
For example, if the feedback signal provided is cooling, the experience of the
wearer may be determined by a combination of the signal intensity (such as the
amount of temperature change a cooling member provides) and the transmission
of
such coolness to the skin (such as through the pressure and body contact a
sensory
element member incorporated into the article achieves due to its structure).
Articles
of the present invention balance both the signal itself and its transmission
to the
wearer to achieve desirable balance in signal onset, duration, noticeability,
and
harmlessness.
Turning then to the first embodiment of the exemplary sensory element
member 80, shown in Figs. 3a, 3b, and 4a, the sensory element member 80
illustrated
is a structure that is formed separately from, but discretely attached to, the
topsheet
60. In particular, and as seen best in Fig. 4a, the sensory element member 80
has a
first laterally extending joining region or end 82 attached to the first waist
region 40,
and a second longitudinally opposing and laterally extending joining region or
end 84
attached to the second waist region 42. In addition, the sensory element 80
may have
a center joining region 86 that may be attached to the crotch region 44. It is
believed
that the attachment of the sensory element member 80 to the crotch region 44
may
assist in stabilizing the member 80, in facilitating fitting of the article 20
to the
CA 02583440 2007-03-30
wearer, in preventing interference with bowel movements and in ensuring good
contact of the member 80 with the wearer's skin.
In one embodiment, the sensory element member may provide a urination
triggered feedback response based upon a sensation of wetness to the wearer.
An
5 example of such a wetness based feedback response is shown in Fig. 3b. As
seen in
Fig. 3b, the sensory element member 80 may comprise a hydrophilic layer 90,
alone
or in combination, as explained in greater detail below. Exemplary materials
suitable
for use in the layer 90 include nonwovens, foams, woven materials, etc. In
particular,
the layer 90 may comprise, by way of illustration and not limitation, rayon,
Lyocell
10 and other cellulose-based materials, cotton, polyester, polypropylene and
polypropylene blends (e.g., with other listed materials, such as a
Lyocell/polypropylene blend), and hydrophilic forms of nonwovens such as SM
(spunbond meltblown), SMS (spunbond meltblown spunbond), and SMMS
(spunbond meltblown meltblown spunbond). Exemplary basis weight ranges for
15 these materials are 10-35 gsm and exemplary bulk density ranges are 0.06-
0.15 g/cm3.
Such materials include Nonwoven Core Cover (10 gsm SSMMS PP) manufactured by
Avgol and a Lyocell/PP blend manufactured by Albis with 5-25 % Lyocell/P5-95 %
PP
(ex. 25 gsm with two layers: 15 gsm philic carded layer with 12 gsm PP and 3
gsm
Lyocell; 10 gsm phobic spunbond PP layer below the 15 gsm carded layer).
20 The layer 90 may have first and second sides 92, 94 that may be parallel to
the
longitudinal axis 30 of the article 20. Preferably, but not necessarily, a
first elastic
member 96 may be attached to the layer 90 at the first side 92, while a second
98
elastic member may be attached to the layer 90 at the second side 94. The
elastic
members 96, 98 may extend along the entire length of the layer 90, or only a
portion
thereof. A fully or partially elasticized layer 90 may to tend to draw the
sensory
element member 80 toward or against the skin of the wearer. Alternatively, the
layer
90 may be formed to have a lesser length than another layer disposed
relatively
exteriorly, etc.
In one variation of this embodunent, the sensory element member 80 consists
essentially of the hydrophilic layer 90. That is, it may be sufficient for the
purpose of
alerting the wearer to an insult of urine that a sufficient surface moisture
quantity of
CA 02583440 2009-11-26
21
urine be maintained for a period of time in the layer 90, thereby providing a
wetness
sensation to the wearer. The Wetness Density (as measured by the Wetness
Density
Test, below) may range from about 0.4 to about 1.5 grams at 60 seconds.
However, according to other variations of this embodiment, an active
component, such as coating or agent, may be applied at 100a, 100b to the layer
90,
which may be referred to as a support layer, as illustrated in solid and
dashed line.
Thus, according to a second variation, the sensory element member 80 may also
comprise an active component in the form of a hydrophilic coating, which may
be
applied at 100a as shown in solid line in Fig. 3b. The hydrophilic coating may
be
disposed in a face-to-face arrangement with the support layer 90. Moreover, as
illustrated, the hydrophilic coating may be disposed on the surface of the
layer 90
closer to the wearer's skin (i.e., body-facing surface).
It will be also recognized that the hydrophilic coating may include a diverse
range of materials, including lotions, creams and the like. Exemplary
hydrophilic
coatings include surfactants, such as the NUWETTM silicone surfactant
available from
GE Silicones of Wilton, CT.
Further, according to a third variation, the sensory element member 80 may
also comprise an active component in the form of a temperature response
element
(composition or structure), which may be applied at 100a. The temperature
response
element may be disposed in face-to-face arrangement with the support layer 90.
Moreover, as illustrated, the temperature response element may be disposed on
the
surface of the layer 90 closer to the wearer's skin (i.e., body-facing
surface). Further,
the temperature response element may be disposed on the support layer 90 in
place of
the hydrophilic coating, in conjunction with the hydrophilic coating, or
combined
(e.g., mixed) with the hydrophilic coating. Further, the temperature response
element
may be impregnated directly into one or more layers comprising the sensory
element
member 80 structure such as support layer 90.
It will be recognized that the temperature response element may include those
materials that produce a temperature change (i.e., involve an endothermic or
an
exothermic reaction), as well as those that produce the sensation that a
temperature
CA 02583440 2009-11-26
22
change has occurred without actually producing a temperature change. For
example,
the temperature response element may be a cooling agent. Further, the cooling
agent
may be the AQUACOOLTM dye manufactured by United Polymer Technology of
Akron, Ohio. The AQUACOOLrM dye is a water-soluble dye that changes
temperatures when brought into contact with water. An example of a cooling
sensation material may be menthol or a menthol derivative, which chemicals are
believed to provide the sensation of a temperature change, while not actually
producing a temperature change. The COOLACT P and COOLACTTM 10 products
manufactured by LIPO Chemicals of Paterson, New Jersey are examples of menthol
derivative products which may be suitable. Other examples of suitable
temperature
change elements and temperature sensation elements may be found in U.S. Patent
No.
6,642,427.
Exemplary suitable sensates that provide a cooling sensation are described in
US Publication No. US20040081680A1 filed October 17, 2003; US Publication No.
2004/0082654 Al; US 2004/0067970 Al; and US 2005/0049553 Al and US patents
4,296,255; 4,296,093; 4,226,988; 4,193,936; 4,178,459; 4,153,679; 4,150,052;
4,070,496; 4,070,449; 4,034,109; 4,033,994; 4,032,661; 4,020,153; 4,459,425;
6,267,974; 6,592,884; 6,328,982; 6,359,168; 6,214,788; 5,608,119; and
6,884,906.
Exemplary preferred senates that provide a cooling sensation described in US
Publication No. 2004/0082654 Al can be provided alone or in combination, and
include ketals such as Frescolata MGA (available from Symrise), cyclic
carboxamides such as WS-3 (available as ISE 3000 from Qardma, Inc.), aliphatic
carboxamides such as WS-23 (available as ISE 1000 from QarBma, Inc.),
cyclohexanol derivatives such as Coolact Pa( available from Takasago), and
cyclohexyl derivatives such as TK10 (Takasago) and menthyl lactate, also known
as
Frescolata ML (Symrise).
Still further suitable sensates that provide a cooling sensation that can be
provided alone or in combination include 1-(2-hydroxyphenyl-)-4-(2-nitrophenyl
1,2,3,6-tetrahydropyrimidine-2-one, also known as Icilin available from Biomol
International, and derivatives thereof; ethyl 3-(p-menthane-3-carboxamido)
acetate,
also known as WS-5 (available from Millenium Specialty Chemicals as WinSenseTM
Extra); N-(4-methoxyphenyl)-p-menthane-3-carboxamide, also known as WS-12; N-
CA 02583440 2007-03-30
23
t-butyl-p-menthane-3-carboxamide, also known as WS-14; 1-glyceryl-p-menthane-3-
carboxylate, also known as WS-30; ethylene glycol p-menthane-3-carboxylate,
also
known as WS-4; 3-(1-menthoxy)-2-methylpropane-1,2-diol; geraniol; eucalyptol;
linaol; hydroxycitronellal; paramenthane-3,8-diol, also known as PMD-38
(Takasago
International); menthyl pyrrolidone carboxlate, also known as Questice
(available
from Quest International); 2-isopropyl-5-methylcyclohexyl-4-(dimethylamino)-4-
oxobutanoate; (-)-Cubebol; N-(4-cyanomenthylphenyl)-p-menthanecarboxamide;
(1 R,3R,4S)-3-menthyl-3,6-dioxaheptanoate; (1 R,2S,5R)-3-menthyl-
methoxyacetate;
(1R,2S,5R)-3-menthyl-3,6,9-trioxadecanoate; (1R,2S,5R)-3-menthyl-(2-hydroxy-
ethoxy) acetate; (1R,2S,5R)-menthyl-11-hydroxy-3,6,9-trioxaundacanoate; (-)-
Isopulegol; cis and trans p-menthane-3,8-diol, also known as Coolact 38D
(Takasago International); and Cooling Agent 10 from Taksago International
menthol
and derivatives.
The cooling sensate(s) are desirably delivered to the skin in a form capable
of
stimulating the cool-sensing nerves immediately (i.e., within 30 seconds,
alternatively
15 seconds) subsequent to contact with urine. In one embodiment, the cooling
sensate(s) are in solid form and are disposed proximal to, or on, the wearer-
facing
surface of the article 20. The sensate(s) can dissolve in the urine and thus
contact the
skin in an aqueous-based phase where they function to stimulate the cool-
sensing
nerves.
Moreover, according to a fourth variation, the sensation element member 80
may comprise an active component in the form of a hydrophobic coating, which
may
be applied at 100b as shown in dashed line in Fig. 3b. According to this
variation, the
hydrophilic coating and/or temperature response element may or may not be
included
(the temperature response element being combinable with either the hydrophilic
or
hydrophobic agent, if present). Like the hydrophilic coating, the hydrophobic
coating
may be disposed in a face-to-face arrangement with the support layer 90.
Moreover,
as illustrated, the hydrophobic coating may be disposed on the surface of the
layer 90
between the layer 90 and the topsheet 60, or the surface further from the
wearer's skin
(i.e., the opposite surface).
CA 02583440 2007-03-30
24
It will be also recognized that the coating 100b may include a diverse range
of
materials, including lotions, creams etc. Exemplary coatings may comprise
hydrophobic coatings (HFC) and liquid-impermeable surface coatings (LISC). In
particular, the coating may be made in accordance with the disclosure of U.S.
Published Application No. 2005/0177123. Alternatively, the coatings may be
acrylic
polymer (e.g., acrylamide, ethyl alcohol, n-butyl alcohol, methyl-
methacrylate,
acrylamide, acrylonitrile, or combinations thereof) emulsions manufactured and
sold,
for example, under the ROHATOL tradename by Lanxess Corp. of Pittsburgh, Pa,
the
RH-MW1845K tradename by Rohm & Haas of Philadelphia, Pennsylvania, or the
FA1, FA2, or FA3 tradenames by PolymerLatex International GmbH of Marl,
Germany.
In fact, the hydrophilic and hydrophobic coatings and temperature response
elements described above may be used with other sensory element members, as
will
be discussed below. Moreover, the coatings and agents may be useful in
conjunction
with the structures described in U.S. Patent No. 6,627,786, among others. As
an
alternative to coatings, response agents may be impregnated into any desired
structure
of the article to provide an integral layer having the desired response
functionality.
The spacing of the first and second sides 92, 94 of the layer 90 and the width
of the coating, if present, may be determined to allow enough liquid to bypass
the
sensory element member 80 to the core 64 so as to prevent flooding. Flooding
may
result in leakage of the article 20 during urination, which is undesirable in
the article
20 when it is a diaper or training pant, for example. Consequently, it will be
recognized that the dimensions of the layer 90 and coating may be determined
to
prevent flooding while at the same time wicking sufficient liquid to create a
sensation
of wetness for the user.
During insults of urine, the layer 90 allows urine to penetrate in the z-
direction
and also provides a medium for the flow of urine in the x-y plane via wicking.
The
layer 90 and/or the coating may enhance the movement of the passage of the
urine in
the x-y plane, thereby expanding the wetted area of the sensory element
member,
which preferably is held in contact with the wearer's skin. The wicking in the
x-y
plane causes the urine to spread out and effectively wet a large area before
being
CA 02583440 2007-03-30
absorbed into the absorbent assembly, thereby maximizing the wetness signal
experienced by the wearer.
It may be desired that the sensory element member 80 be provided with
additional ingredients such as a pH buffer, enzyme inhibitors, skin care
compositions
5 including Zinc Oxide or any of the exemplary skin benefit ingredients
described in
U.S. Patents 6,118,041 and 6,107,535. Such ingredients can be present to
offset any
impact of urine being in contact with the skin.
It is desirable that the sensory element and sensory element member provide a
feedback response within a short time after the onset of urination. For
example, the
10 feedback response may be provided within about 60 seconds of the urination
event, or
may be provided within about 30 seconds or the urination event, or may be
provided
within about 15 seconds of the urination event. The time response to feedback
onset
may vary depending on the type of feedback provided. For example, if the
feedback
response is a wetness sensation, it may be desired that the article provide
the feedback
15 response within about 30 seconds of the urination event, within about 15
seconds of
the urination event, or within about 5 seconds of the urination event. The
time
response to feedback onset may vary depending on the type of feedback
provided.
For example, if the feedback response is a wetness sensation, it may be
desired that
the article provide the feedback response within about 30 seconds of the
urination
20 event, or within about 15 seconds of the urination event. If the feedback
response is a
temperature change or temperature change sensation, it may be desirable to
provide
the feedback response within about 300 seconds of the urination event, or
within
about 15 seconds of the urination event, or within about 10 seconds of the
urination
event. Additionally, if the feedback response is a temperature change, it may
be
25 desirable to provide a minimum rate of temperature change to produce the
desired
noticeability and timeliness of response. The minimum temperature change rate
desired at some point in the first 2 minutes following a urination event might
be at
least about 0.5 C/second, or at least about 1 C/second, or at least about 2
C/second, or
at least about 3 C/second, or at least about 5 C/second. The specified rate of
temperature change typically is limited to a specific duration in order to
prevent the
temperature from decreasing into the range of temperatures perceived by the
body as
CA 02583440 2007-03-30
26
noxious cold. The greater the rate of temperature change, the shorter the
required
duration of the temperature change rate. Typically, the duration of the
specified rate
of temperature change is in the range of between about 1 second and about 30
seconds, although longer durations are possible depending on the temperature
change
rate. Preferably, the duration of the specified temperature change rate is in
the range
of about 2 seconds to about 10 seconds. The temperature may change at some
other
rate prior to and after the time span defined by the duration specified above.
Additionally, in order to provide the wearer a signal correlated as closely as
possible
to the actual urination event, the specified temperature change rate
preferably occurs
within the first two minutes, more preferably within the first minute, still
more
preferably within the first 20 seconds, and most preferably within the first 5
seconds
following contact with urine. By the term "occurs" is meant that at least the
specified
temperature change rate begins within the defined period following urination,
although the entire duration of the temperature change rate may fall within
the
specified timeframe.
For purposes of determining the onset of a feedback response, one or more of
the appropriate measurement techniques described below may be used. For
example,
if the feedback response provided by a particular sensory element in a
particular
article is a temperature change, the Temperature Change Response Measurement
using a thermocouple described below may be used. If the feedback response
provided is a wetness sensation, for example, the Wetness Density Test using
filter
paper described below may be used. These techniques provide one of skill in
the art
with the ability to determine when a feedback response is deemed to be
"provided"
(i.e. when it starts) and how long it is deemed to persist for purposes of the
present
application, including the claims.
If the feedback response is a temperature change, such as a temperature
decrease, the temperature change should be of a sufficient magnitude to be
noticed by
the wearer. A temperature change of at least 5 C (as measured from body
temperate
or about 37 C) might be desired to be noticeable. Cool receptors in the skin
are most
sensitive at about 25 C (representing a temperature change of about 12 C from
body
temperature). Cool signal activity is still high at 20 C, and the body
typically senses
CA 02583440 2007-03-30
27
"cool" down to about 15 C. Temperatures lower than 10-15 C are perceived as
"cold." It, therefore, may be desirable to provide a temperature change signal
greater
than about 5 C, preferably about 10-15 C, or a change of up to about 25 C (as
measured in terms of degrees change from body temperature). It may also be
desired
in some embodiments to have a cold signal (a large temperature change) for
children
who do not easily perceive more mild "cool" signals. Such a "heavy duty" or
less
easy to ignore cold signal could be provided by a cooling member which cools
the
skin to a temperature of less than about 15 C. Skin temperatures of less than
10 C,
however, should be avoided since such temperatures are "noxious cold" and
start to
result in "burning pain." Such signals would not accomplish one of the design
objectives of "harmless" described above.
The coolness (or temperature change or temperature change sensation
generally) is usually felt as long as the temperature is near the minimum
temperature
(in the case of coolness) resulting from the cooling agent. Once the
temperature
begins to increase again (or even when the rate of cooling has declined
sufficiently)
the cooling becomes imperceptible to the wearer. This is true even if the
resulting
temperature is lower than the starting temperature. As an example if the skin
(or
absorbent article surface) is near about 37 C and is insulted with urine of
approximately 37 C, the sensory element member may trigger a temperature
change
response by cooling the skin to a minimum temperature of about 25 C within
about
seconds. As the temperature change effect begins to dissipate, and the
temperature
rises, the wearer may not perceive coolness once the temperature exceeds about
28 C.
It will be appreciated that in this example 28 C represents a temperature of
the
minimum temperature (25 C) plus 25 % of the maximum delta T (maximum
25 temperature change initial 37 C or 12 C in this example). Therefore, the
"duration"
of the coolness based feedback may be defined in this example as the time
between
the urination event and the time when the surface temperature returns to a
point at
which the temperature change which is no longer greater than 75 % of the
maximum
change. The duration of this time may be about 120 seconds, or less than about
150
30 seconds, or less than about 300 seconds. Durations under this description
of about 30
seconds or about 60 seconds may be acceptable for stronger signals. The
duration
desired may be inversely related to the signal intensity.
CA 02583440 2007-03-30
28
In order to readily compare one article to another when such articles
incorporate temperature change based feedback mechanisms, the surface
temperature
of the article using a thermocouple system (as described in the Temperature
Change
Response Measurement, below) may be recorded 30 seconds after insulting the
article
with 75mL of 0.9% saline at 37 C. A typical desired temperature change at this
time
may range from about 5 C to about 20 C.
If the feedback response is a wetness sensation, the amount of moisture
contacting the skin should be of a sufficient quantity to be noticed by the
wearer. For
example, a surface Moisture Density (as measured by the Moisture Density Test)
of
greater than about 2 mg/cm2 at 60 seconds or greater than about 4 mg/cm2 at 60
seconds or greater than about 5 gm/cm2 at 60 seconds may be desired. The
wetness
desirably does not persist for an undue period of time. For example, it may be
desired
that the surface Moisture Density at 10 minutes is less than about 80% or less
than
about 75% or less than about 70% of the surface Moisture Density measured at
60
seconds.
It is also desirable when designing the sensory element member to take into
account the transmission of the feedback signal to the wearer. The signal
generated
by the sensory element should be incorporated directly or indirectly to a
sensory
element member which contacts the wearer's skin to elicit a sensation.
Ideally, the
article and sensory element member are designed to enable at least
intermittent, and
preferably virtually continuous, contact between the wearer facing surface of
the
sensory element member and the wearer's skin in all body positions and during
all
activities in which the wearer may engage. Preferably, the area of contact on
the
wearer's body is an area having a relatively higher concentration of nerve
endings. In
the region of the body commonly covered by disposable absorbent articles such
as
pant-like diapers or training pants, the genital, perineal, perianal, inner
thigh, and
lower abdomen have a relatively higher nerve concentration are the preferred
contact
areas.
One preferred method of promoting contact between the sensory element
member and the wearer is to provide a raised sensory element member as
described
herein. In these embodiments, the skin contact is effected by providing a
sensory
CA 02583440 2007-03-30
29
element member at least locally detached from underlaying layers in at least
the
desired region of contact and elastically foreshortening the sensory member,
or a
structure to which the sensory element member is affixed, causing the sensory
element member to be lifted in the z-direction toward the body. Additionally,
in
certain embodiments, the elastic lifting members cause the sensory element
member
to contact the body with sufficient force and resiliency to allow the sensory
element
member to continue to contact the body during wearer motion, or to quickly re-
establish contact in the event that contact is temporarily broken
Other methods of promoting skin contact may also be employed in place of, or
in addition to the method described hereinabove. For example, at least a
portion of
the skin contacting surface of the article may comprise a contact promoting
substance
that adheres gently to the wearer's skin and resists casual disengagement.
Exemplary
contact promoting substances may include skin care compositions such as lotion
as
described in US. Patent Nos. 5,607,760; 5,609,587; 5,635,191; 5,643,588;
5,968,025;
6,118,041; 6,120,488; 6,120,783; 6,153,209; 6,156,024; and 6,166,285, sticky
lotions
as described in International Patent Application WO 2004/087092, and adhesives
such as body adhesives. In certain embodiments a water-activatable adhesive
may be
desirable as it would only promote contact once the wearer urinates. Water
activatable
adhesives for use in disposable absorbent articles are disclosed in US
6,623,465. The
skin contact promoting substance may be disposed on at least a portion of the
sensation member 80 or in a region of the topsheet 60 or other supporting
structure in
proximity to the sensory element member 80.
Skin contact may also be promoted via resilient 3-dimensional structures
comprising foams or core materials. These structures serve to hold the sensory
element member in contact with the wearer even during wearer motion due to
their 3-
dimensional resilient nature. In some embodiments, these structures may be
relatively
thin and unobtrusive when in a dry state and may be triggered to grow in the z-
direction by contact with urine. For example, the structure may comprise a
compressed foam encapsulated in a water or pH sensitive material wherein the
foam
is allowed to expand upon contact with urine or the structure may comprise a
composition capable of evolving gas held within a semi-permeable membrane such
CA 02583440 2007-03-30
that it inflates upon contact with urine. Further examples of structures that
increase in
thickness upon contact with urine include those described in US Patents
3,881,491;
3,921,232; 5,330,459; 6,186,991; 5,797,892; 5,428,076; and 5,124,188.
The physical structure of the sensory element member, its body contact area,
5 and force of contact may vary depending upon the type of signal, intensity
of signal,
and coupling of the sensory element to the sensory element member. For
example, if
the feedback signal is a temperature change element, the amount of temperature
change element needed depends upon the degree of temperature change provided
its
location in the article, and how much surface area having such temperature
change
10 element is provided in a body contacting structural member in any given
body
position. It has been found during development of the present invention that
using the
temperature change mechanisms described above, for example, that the desired
cool
signal is provided when the body contacting portion of the sensory element
member
has an area of greater than about 25 cm2, or greater than about 50 cm2, or
greater than
15 about 100 cm2. In general, the greater the surface area of the sensory
element
member body contacting portion, the less intense the signal itself need be to
produce
the desired result. One of skill in the art will also recognize that the
degree of
coupling of the sensory element to the sensory member will also affect the
desired
body contact. For example, a temperature change sensory element directly
20 impregnated onto the top surface of the sensory element member may more
readily
transmit the signal to the skin than a temperature change sensory element
disposed in
an underlying layer which cools the sensory element member which in turn cools
the
skin. In the later case, the indirect transmission of the signal may lead to
greater
desired body contact area and/or force of contact by the sensory element
member.
25 The disposable absorbent article 20 may have visible highlighting,
indicated at
110 in Figure 3a and illustrated as an exemplary pattern of wavy lines and
circles, in
the interior of the article associated with the sensory element member or
members 80
to indicate the presence of the sensory element member or members 80 and
thereby
facilitate an opportunity for the urinary toilet training of the wearer of the
article.
30 Such visible highlighting is described in U.S. Published Application No.
2005/0096612. Although a sensory element lacking this visible highlighting is
fully
CA 02583440 2007-03-30
31
functional in terms of providing a noticeable wetness and/or temperature
signal to the
wearer, the caregiver might overlook or forget the possibility of capitalizing
on each
opportunity for urinary toilet training if the body-facing portion of the
absorbent
article presents a generally uniform appearance, such as in absorbent articles
that
present a generally uniform white appearance on their body-facing surfaces.
Furthermore, once the caregiver decides to mention urinary toilet training to
the wearer, the visible highlighting can serve to draw the wearer's interest
or can be
pointed out by the caregiver and incorporated into an explanation of the
upcoming
opportunity. Thus, the visible highlighting can provide a topic for
conversation
between the caregiver and the wearer on the subject of urinary toilet training
and can
likewise provide a nameable object for reference by the wearer, greatly
simplifying
the mental task required of the wearer who desires to communicate his or her
need to
go to the toilet or to communicate his or her improving recognition of the
wetness
signal provided by the sensory element member.
Even a simple solid coloring form of visible highlighting can serve to
facilitate
an opportunity for urinary toilet training, especially when used with wearers
possessing some recognition of colors or colored forms. In addition, visible
highlighting in the form of a color or colors may facilitate the teaching of
recognition
of colors and differences between colors, and the associated learning may
enhance the
urinary toilet training process in turn.
In addition, the visible highlighting can serve to enhance the self-esteem of
the
wearer through a reminder that he or she is mature enough to be engaged in
urinary
toilet training. This effect can be compounded when the wearer succeeds in
recognizing the need to go to the toilet and then sees the dry condition of
the visibly
highlighted sensory element member inside the article after pulling it down.
The visible highlighting may be provided by means of printing onto a surface
of the sensory element member or one of its layers. For example, solid
coloring or a
graphic may be printed onto a surface of the coating underlying the water-
permeable
layer. As another example, an adhesive or a gel may be printed onto a surface
of
either of the two layers. Such an adhesive or gel may be colored differently
from the
CA 02583440 2007-03-30
32
surrounding area. Alternatively, the adhesive or gel may be uncolored or may
have
the same color as the surrounding area, but may still provide visible
highlighting by
forming a distinctive raised area or pattern and/or by surrounding a
distinctive
recessed area or pattern.
In addition to visible highlighting on the sensory element member itself,
visible highlighting or other graphical elements can be provided elsewhere on
the
article. This can be in addition to or instead of on the sensory element
member.
In some embodiments, the visible highlighting may become more or less
visible when the sensation member is wetted. In addition, the visible
highlighting
may change color when the sensation member is wetted. Any of these effects may
be
created by the use of inks or dyes or other agents that undergo chemical
reactions or
are dispersed or concentrated when wetted by urine. In general, any of the
wetness
indicating compositions commonly used in externally visible wetness
indicators, such
as so-called "appearing" or "disappearing" wetness indicators that may become
more
or less visible when wetted and in wetness indicators that may change color
when
wetted, may be used for these versions of visible highlighting.
Wetness indicating compositions used for the visible highlighting of the
sensory element member may be visible from the body-facing surface of the
absorbent article or may be included in the article so as to be visible from
the outside,
or from both. If the wetness sensation member is disposed on the interior
surface of
the article, a caregiver might apply different techniques to the task of
urinary toilet
training as compared to using an absorbent article having only a wetness
indicator
visible from the outside of the article. For example, while the change in an
exterior
wetness indicator is visible for all to see, any change in the visible
highlighting of an
interior sensory element member remains "private" until either the caregiver
or the
wearer peers into the absorbent article or it is removed. Either or both
approaches can
be used or interchanged as desired to re-enforce the other training features
described
herein.
The article 20 may comprise an internal graphic 110, a first external graphic,
and a second external graphic. The internal graphic may be permanent, while
the
CA 02583440 2007-03-30
33
external graphics may be "appearing" or "disappearing." The first external
graphics
may include a character image resembling a boy and a text graphic including
words
forming a message, such as "Remember to go to the potty!" While the graphics
may
include text, the primary form of communication may be symbols, icons, or
other
markings other than words, so that a pre-literate child may comprehend and
follow the
instructions or other information indicated by the graphics, although it is
not
necessary for the images to be understood at this level. The second external
graphics
may include an image that may be associatively correlated to the permanent
graphic,
such as a dog or stars.
Variations regarding the internal/external graphics are possible. For example,
a permanent external image may be combined with the first and second external
graphics, or only one external graphic may be included. Furthermore, character
images other than a boy may be provided, such as a girl, an animal (which may
be
anthropomorphic), a cartoon character, and the like. Still further, additional
or
alternative text may be provided. Additionally exemplary graphics, graphics
characteristics and/or arrangements (e.g., timings, themes, scenes,
storylines, etc.), the
materials that are suitable for forming the graphics, and the arrangement
and/or
joining of these materials to the article 20 are described in co-pending and
commonly
assigned U.S. Patent Application No. 11/098,362, filed in the name of Roe et
al. on
April 4, 2005.
Even in embodiments in which the appearance of the visible highlighting is
not affected by its being wetted, the associative correlation of the
respective visible
forms of an externally visible marking and the visible highlighting may serve
to
facilitate an opportunity for urinary toilet training. For example, if both
the externally
visible marking and the visible highlighting have the visible form of similar
graphics,
the externally visible marking can serve to draw the wearer's interest or can
be
pointed out by the caregiver and incorporated into an explanation of the
ongoing
opportunity for urinary toilet training.
Turning next to Figs. 5a and 5b, a second embodiment of a sensory element
member 180 is illustrated therein. Similar to the sensory element 80, the
sensory
element member180 has first and second sides 192, 194 that are arranged
parallel to
CA 02583440 2007-03-30
34
the longitudinal axis 30 of the article 20. Moreover, elastic members 196, 198
may be
attached to the sensory element memberl80 at the sides 192, 194 so as to
elasticize
the sensory element member 180, which may assist in bringing the sensory
element
member 180 into close contact with the skin of the wearer, increasing the
efficacy and
reliability of the signal transfer to the skin. Further, the sensory element
may include
an active component, such as (i) a coating, which may be a hydrophilic coating
disposed on a body-facing surface or a hydrophobic coating disposed on an
opposite
surface, (ii) a temperature sensation element, which may be disposed on either
surface
and in substitution for, in conjunction with, or combined with the coating,
and/or (iii)
a layer of hydrophilic material, such as was described relative to the layer
90 above
and which also may be disposed on a body-facing surface.
The sensory element member 180 differs from the sensory element member 80
in that the structure corresponding to the support layer 90 is formed from a
section of
the topsheet 60 spaced from the core 64. That is, a section of the topsheet 60
is folded
to define support layer structure of the member 180, and, in particular, is
folded along
the sides 192, 194. The elastic members 196, 198 are then disposed beneath the
topsheet 60 in the space between the topsheet 60 and the core 64. In this
fashion, the
sensory element member180 may be integrated to a greater degree to the
remainder of
the article 20 than the member 80, thereby reducing the likelihood that the
sensory
element member 180 will become detached from the remainder of the article 20.
The sensory element member 180 may include other features in common with
the sensory element member 80. For example, the coatings and agents disposed
at
200a, 200b may include those exemplary coatings and agents listed above.
Moreover,
while not illustrated, a visible graphic 110 may be include on a surface of
the sensory
element memberl80, providing one or more of the advantages discussed above.
Turning then to Figs. 6a and 6b, a third embodiment of the sensory element
member 280 is illustrated, with the barrier leg cuffs folded back slightly in
Fig. 6a to
expose the sensory element member 280. The sensory element member 280 has a
first laterally extending end 282 and a second longitudinally opposing and
laterally
extending end 284. As will be recognized, the distance between the ends 282,
284 is
shorter than the distance between the ends 50, 52, or even the distance
between end
CA 02583440 2007-03-30
50 and the crotch region 44. According to the embodiment, the position of the
ends
282, 284 relative to the ends 50, 52 and the spacing between the ends 282, 284
is such
that the likelihood that the sensory element member 280 will be wetted with
urine is
enhanced.
5 The sensory element member 280 includes a layer 290. The layer 290 extends
between the ends 282, 284. Additionally, a first longitudinal edge 292 of the
layer
290 is attached to a first barrier leg cuff 294 attached to the topsheet 60,
while a
laterally opposed, longitudinal edge 296 is attached to a second, spaced
barrier leg
cuff 298, also attached to the topsheet 60. Moreover, each barrier leg cuff
294, 298
10 includes an elastic member 295, 299. In this fashion, it is not necessary
to attach
separate elastic members to the support layer 290, but the elastic members
295, 299 of
the barrier leg cuffs 294, 298 instead may urge the sensory element 280 into
contact
with the skin of the wearer.
In fact, it is believed that the attachment of the sensory element member 280
15 to the barrier leg cuffs 294, 298 may permit greater control over the
spacing of the
sensory element member 280 relative to the topsheet 60 (i.e., distance between
member 280 and topsheet 60) than had heretofore been possible. That is, by
attaching
the sensory element 280 along its sides 292, 296, rather than at its ends 282,
284, the
spacing of the member 280 relative to the topsheet 60 may be better controlled
than in
20 those embodiments wherein the member is attached at its ends, or
potentially even in
those embodiments where the member is integrated into the topsheet 60 and
elastic
members disposed internal to the topsheet 60 are used to define, at least in
part, the
sensory element. Additionally, by attaching the sensory element member 280 to
the
leg cuffs 294, 298, the dimension of the sensory element member 280
perpendicular
25 to the longitudinal axis may be greater than, for example, the sensory
element
members 80, 180 discussed above.
Similar to the embodiment shown in Figs. 3a and 3b, the sensory element
member 280 may consist essentially of the layer 290, or may comprise the layer
290
in combination with a coating or an agent, which coating or agent may be
disposed in
30 a face-to-face arrangement with the layer 290, which may be referred to as
a support
layer. The coating may be a hydrophilic coating disposed at 300a on the body-
facing
CA 02583440 2007-03-30
36
surface of the layer 290, or a hydrophobic coating disposed at 300b on the
opposite
surface. Additionally, a temperature sensation element may be disposed at 300a
on
either surface and in substitution for, in conjunction with, or combined with
the
coating.
The sensory element member 280 may include other features in common with
the sensory element members 80, 180. For example, the coatings and agents may
include those exemplary coatings and agents listed above. Additionally, while
not
illustrated, a visible graphic 110 may be include on a surface of the sensory
element
member 280, providing one or more of the advantages discussed above.
In additional embodiments shown in Figs. 7a-7c, the sensation member 380 or
any layer including the sensation member can be disposed in two parallel Z-
folds 387
formed along the longitudinal length of the absorbent article. The Z-folded
sensation
member 380 or any layer including the sensation member may be attached to the
underlying layers along the longitudinal edges of the topsheet 60 allowing the
portion
between the Z-folds of the topsheet 60 to float freely. Elastic elements 96,
98 may be
disposed along the central region of the sensation member 380 in order to
deflect the
central region outward away from the absorbent core 64. Elastic elements 96,
98 may
be disposed between layers of the topsheet 60, between layers of the sensation
member 380, between the topsheet 60 and sensation member 380, or any other
configuration that connects the elastic elements 96, 98 to the topsheet 60
and/or
sensation member 380. The central region 385 may have a first side edge 385a
and a
second side edge 385b such that at least one of said side edges 385a, 385b has
a
projected height h measured the z direction between the side edge and the base
of the
sensation member that connects the sensation member to the absorbent article.
A disposable absorbent article including a sensation member is attached to the
inner surface of a curved plate (i.e. the concave surface relative to the
hypothetical
center of the circle having the same curvature as the plate) having a radius
of
curvature of about 250mm. The disposable absorbent article is attached to the
plate
such that its garment facing surface (i.e. outer cover) is in contact with the
plate. In
this configuration, the elastic member(s) that are disposed longitudinally on
the
disposable absorbent article are in an elongated configuration and are
applying a force
CA 02583440 2007-03-30
37
that is pulling any layer attached to the elastic member away from the core. A
ruler
having one end contacting the base of the sensation member and the other end
pointing toward the center of the hypothetical circle formed by the curved
plate, may
be used to measure the distance between the base of the sensation and the side
edge of
the sensation member.
The Z-folded sensation member 380 allows the central region 385 to be
suspended away from the core 64 and the topsheet 60. The combination of the Z-
folded sensation member 380 and the elastic elements 96, 98 maintains the
sensation
members in proximity to the wearer's skin in the event that the diaper sags or
fits
loosely around the wearer.
Alternatively, additional elastic elements 96a, 98a may be disposed along the
central region of the Z-folded sensation member. Elastic elements 96a, 98a,
may be
disposed between layers of topsheet 60, between layers of the sensation member
380,
between the topsheet 60 and sensation member 380, or any other configuration
that
connects the elastic elements 96a, 98a to the topsheet 60 and/or sensation
member
380. Elastic elements 96a, 98a provide additional support to prevent sagging
and
promote contact with the wearer's skin.
The absorbent article may also include a first barrier leg cuff 394 and a
second
barrier leg cuff 398, which may include elastic members 395, 399 respectively.
First
and second barrier leg cuffs are disposed on the absorbent article such that
the Z-
folded sensation member 380 is located between the barrier leg cuffs 395, 399.
At
least one of the first barrier leg cuff 394 and a second barrier leg cuff 398
has a
projected height H measured the z direction between an upper edge of the
barrier leg
cuff and the base of the barrier leg cuff that connects the barrier leg cuff
to the
absorbent article.
The projected height h and H may be measured according the following
method.
A disposable absorbent article including a sensation member is attached to the
inner surface of a curved plate (i.e. the concave surface relative to the
hypothetical
CA 02583440 2007-03-30
38
center of the circle having the same curvature as the plate) having a radius
of
curvature of about 250mm. The disposable absorbent article is attached to the
plate
such that its garment facing surface (i.e. outer cover) is in contact with the
plate. In
this configuration, the elastic member(s) that are disposed longitudinally on
the
disposable absorbent article are in an elongated configuration and are
applying a force
that is pulling any layer attached to the elastic member away from the core. A
ruler
having one end contacting the base of the sensation member and the other end
pointing toward the center of the hypothetical circle formed by the curved
plate, may
be used to measure the distance between the base of the sensation and the side
edge of
the sensation member. The side edge of the sensation member is gently extended
to
its maximum height (i.e. without applying a force that would cause the
sensation
member to be torn or destroyed) and then record the measurement. The projected
height measurement can be repeated at various points along the sensation
member in
order to determine its maximum projected height. The ruler may be moved such
that
one end is in contact with the base of an outer leg cuff and its other end is
pointing
towards the center of the hypothetical circle passing through the curved
plate. The
projected height H may be determined by measuring distance between the base of
the
outer leg cuff and the upper edge of the outer leg cuff. The upper edge of the
outer
leg cuff is gently extended to its maximum height (i.e. without applying a
force that
would cause the outer leg cuff to be torn or destroyed) and then record the
measurement. The projected height measurement can be repeated at various
points
along the outer leg cuff in order to determine its maximum projected height.
In one embodiment, the projected height h of at least one of the first side
edge
385a and a second side edge 385b is between 90% and 300%, preferably between
100% and 250%, more preferably between 100% and 200% of the projected height H
of at least one of the first barrier leg cuff 394 and a second barrier leg
cuff 398.
In one embodiment, the projected height h of at least one of the first side
edge
385a and a second side edge 385b is between 15mm and 50mm, preferably between
20mm and 45mm, more preferably between 25mm and 40mm.
In addition to the features described above, the disposable absorbent article
20
may also include a variety of features known in the art, such as slit
openings, outer leg
CA 02583440 2007-03-30
39
cuffs, front and rear ear panels, waist cap features, elastics, and the like
to provide
desired fit, containment, and aesthetic characteristics. Such additional
features are
well known in the art and are described in U.S. Patent Nos. 3,860,003;
5,151,092; and
6,482,191 among others. Additionally, a transfer layer, which may also be
referred to
as an acquisition or distribution layer, may be disposed between the topsheet
60 and
the core 64. Moreover, the elements discussed above may be modified from their
illustrated forms.
Various sublayers may be disposed between the topsheet and the outer cover.
The sublayer may be any material or structure capable of accepting, storing or
immobilizing bodily exudates. Thus, the sublayer may include a single material
or a
number of materials operatively associated with each other. Further, the
sublayer may
be integral with another element of the pull-on garment or may be one or more
separate elements attached directly or indirectly with one or more elements of
the
disposable absorbent article. Further, the sublayer may include a structure
that is
separate from the absorbent core or may include or be part of at least a
portion of the
absorbent core.
Suitable materials for use as the sublayer may include large cell open foams,
macro-porous compression resistant nonwoven highlofts, large size particulate
forms
of open and closed cell foams (macro and/or microporous), highloft nonwovens,
polyolefm, polystyrene, polyurethane foams or particles, structures comprising
a
multiplicity of vertically oriented looped strands of fibers, absorbent core
structures
described above having punched holes or depressions, and the like. (As used
herein,
the term "microporous" refers to materials which are capable of transporting
fluids by
capillary action. The term "macroporous" refers to materials having pores too
large to
effect capillary transport of fluid, generally having pores greater than about
0.5 mm in
diameter and, more specifically, having pores greater than about 1.0 mm in
diameter.)
One embodiment of a sublayer includes a mechanical fastening loop landing
element,
having an uncompressed thickness of about 1.5 millimeters available as XPL-
7124
from the 3M Corporation of Minneapolis, Minnesota. Another embodiment includes
a 6 denier, crimped and resin-bonded nonwoven highloft having a basis weight
of 110
grams per square meter and an uncompressed thickness of 7.9 millimeters which
is
CA 02583440 2009-11-26
available from the Glit Company of Wrens, Georgia. Other suitable absorbent
and
nonabsorbent sublayers are described in U.S. Patent No. 6,680,422 and U.S.
Patent
No. 5,941,864. Further, the sublayer, or any portion thereof, may include or
be coated
with a lotion or other known substances to add, enhance or change the
performance or
5 other characteristics of the element.
In embodiments of the present disclosure, a disposable wearable absorbent
article can include a stretchable outer cover. For example, the outer cover
can be a
uniaxially stretchable outer cover, configured to stretch in one direction.
Also as an
example, the outer cover can be a biaxially stretchable outer cover,
configured to
10 stretch in two directions. In various embodiments, the outer cover can be
configured
as described in US non-provisional patent application entitled "Biaxially
Stretchable
Outer Cover for an Absorbent Article," Publication No. 2007/0287348 filed on
November 15, 2006.
In embodiments of the present disclosure, a disposable wearable absorbent can
15 include an outer cover configured in various ways, including configurations
of part or
all of the outer cover as stretchable, non-stretchable, with an elastic
nonwoven, with
an elastic film and extensible nonwoven, with an extensible film and an
elastic
nonwoven, pre-stretched with elastic strands allowed to contract, mechanically
activated, with zero strain laminate, and/or combinations of these and any
other outer
20 cover configurations. In various embodiments of the present disclosure, a
disposable
wearable absorbent article can include a printed outer cover with various
basis
weights, chemistries, and/or mechanical activations, as will be understood by
one of
ordinary skill in the art.
Embodiments of the present invention may include acquisition layers and
25 dusting layers, each of which are well known in the art. Acquisition layer
are further
discussed in U.S. Patent No. 5,460,622. Dusting layers are further discussed
in U.S.
Patent No. 4,888,231. Examples of suitable configurations for leg cuffs are
described
in U.S. Patent No. 3,860,003; US. Patent No. 4,909,803; and U.S. Patent No.
4,695,278.
CA 02583440 2007-03-30
41
One preferred embodiment of the present invention includes, but is not limited
to, articles described in U.S. Patent Application No. 2004/0162536 and U.S.
Patent
Application No. 2004/0167486. The aforementioned applications are directed to
absorbent articles having an absorbent core which imparts increased wearing
comfort
to the article and makes it thin and dry. As shown in Figure 8, the absorbent
articles
of the present invention may comprise an absorbent core 64 comprising a
substrate
layer 400, absorbent polymer material 410 and a fibrous layer of adhesive 420.
The
substrate layer 400 is preferably provided from a non-woven material,
preferred non-
wovens include those provided from synthetic fibers, such as PE, PET and PP.
As the
polymers used for non-woven production are inherently hydrophobic, they are
preferably coated with hydrophilic coatings.
In accordance with the present invention, the absorbent material is
immobilized when wet such that the absorbent core achieves a wet
immobilization of
more than 50 %, preferably of more than 60 %, 70 %, 80 % or 90 %.
The substrate layer 400 comprises a first surface and a second surface. At
least
portions of the first surface of the substrate layer 400 are in direct contact
with a layer
of absorbent polymer material 410. This layer of absorbent polymer material
410 is
preferably a discontinuous layer, and comprises a first surface and a second
surface.
As used herein, a discontinuous layer is a layer comprising openings.
Typically, these
openings have a diameter or largest span of less than 10 mm, preferably less
than 5
mm, 3 mm, 2 mm and a span of more than 0.5 mm, 1 mm or 1.5 mm. At least
portions of the second surface of the absorbent polymer material layer 410 are
in
contact with at least portions of the first surface of the substrate layer
material 400.
The first surface of the absorbent polymer material 410 defines a certain
height 412 of
the layer of absorbent polymer above the first surface of the layer of
substrate material
400. When the absorbent polymer material layer 410 is provided as a
discontinuous
layer, portions of the first surface of the substrate layer 400 are not
covered by
absorbent polymer material 410. The absorbent core 64 further comprises a
thermoplastic composition 420. This thermoplastic composition 420 serves to at
least
partially immobilize the absorbent polymer material 410.
CA 02583440 2007-03-30
42
In one preferred embodiment of the present invention the thermoplastic
composition 420 can be disposed essentially uniformly within the polymeric
absorbent material 410.
However, in an even more preferred embodiment of the present invention the
thermoplastic material 420 is provided as a fibrous layer which is partially
in contact
with the absorbent polymer material 410 and partially in contact with the
substrate
layer 400. In this preferred structure the absorbent polymer material layer
410 is
provided as a discontinuous layer, a layer of fibrous thermoplastic material
420 is laid
down onto the layer of absorbent polymeric material 410, such that the
thermoplastic
layer 420 is in direct contact with the first surface of the layer of
absorbent polymer
material 410, but also in direct contact with the first surface of the
substrate layer 400,
where the substrate layer is not covered by the absorbent polymeric material
410. This
imparts an essentially three-dimensional structure to the fibrous layer of
thermoplastic
material 420 which in itself is essentially a two-dimensional structure of
relatively
small thickness (in z-direction), as compared to the extension in x- and y-
direction. In
other words, the fibrous thermoplastic material layer 420 undulates between
the first
surface of the absorbent polymer material 410 and the first surface of the
substrate
layer 400.
Thereby, the thermoplastic material 420 provides cavities to hold the
absorbent polymer material 410, and thereby immobilizes this material. In a
further
aspect, the thermoplastic material 420 bonds to the substrate 400 and thus
affixes the
absorbent polymer material 410 to the substrate 400. Highly preferred
thermoplastic
materials will also penetrate into both the absorbent polymer material 410 and
the
substrate layer 400, thus providing for further immobilization and affixation.
Of course, while the thermoplastic materials disclosed herein provide a much
improved wet immobilization (i.e., immobilization of absorbent material when
the
article is wet or at least partially loaded), these thermoplastic materials
also provide a
very good immobilization of absorbent material when the article is dry.
In accordance with the present invention, the absorbent polymer material 410
may also be mixed with absorbent fibrous material, such as airfelt material,
which can
CA 02583440 2007-03-30
43
provide a matrix for further immobilization of the super-absorbent polymer
material.
However, preferably a relatively low amount of fibrous cellulose material is
used,
preferably less than 40 weight %, 20 weight %, or 10 weight % of cellulose
fibrous
material as compared to the weight of absorbent polymer material 410.
Substantially
airfelt free cores are preferred. As used herein, the term "absorbent fibrous
material"
is not meant to refer to any thermoplastic material 420 even if such
thermoplastic
material is fiberized and partially absorbent.
The absorbent core of the present invention may further comprise a cover
layer. This cover layer may be provided of the same material as the substrate
layer
400, or may be provided from a different material. Preferred materials for the
cover
layer are the non-woven materials. In this embodiment, portions of the cover
layer
bond to portions of the substrate layer 400 via the thermoplastic material
420.
Thereby, the substrate layer 400 together with the cover layer provides
cavities to
immobilize the absorbent polymer material 410.
The areas of direct contact between the thermoplastic material 420 and the
substrate material 400 are referred to as areas of junction 440. The shape,
number, and
disposition of the areas of junction 440 will influence the immobilization of
the
absorbent polymer material 410. The areas of junction can be of squared,
rectangular,
or circular shape. Preferred areas of junction are of circular shape.
Preferably, they
have a diameter of more than 0.5 mm, or 1 mm, or 1.5 mm and of less than 10
mm, or
5 mm, or 3 mm, or 2 mm. If the areas of junction 440 are not of circular
shape, they
preferably are of a size as to fit inside a circle of any of the preferred
diameters given
above.
The areas of junction 440 can be disposed in a regular or irregular pattern.
For
example, the areas of junction 440 may be disposed along lines. These lines
may be
aligned with the longitudinal axis of the absorbent core, or alternatively,
they may
have a certain angle in respect to the longitudinal edges of the core. It has
been
found, that a disposition along lines parallel with the longitudinal edges of
the
absorbent core 64 create channels in the longitudinal direction which lead to
a lesser
wet immobilization. Preferably, therefore the areas of junction 440 are
arranged along
lines which form an angle of 20 degree, 30 degree, 40 degree, or 45 degree
with the
CA 02583440 2007-03-30
44
longitudinal edges of the absorbent core 64. Another preferred pattern for the
areas of
junction 440 is a pattern comprising polygons, for example pentagons and
hexagons
or a combination of pentagons and hexagons. Also preferred are irregular
patterns of
areas of junction 440, which also have been found to give a good wet
immobilization.
Two fundamentally different patterns of areas of junctions 440 can be chosen
in accordance with the present invention. In one embodiment, the areas of
junctions
are discrete. They are positioned within the areas of absorbent material, like
islands in
a sea. The areas of absorbent materials are then referred to as connected
areas. In an
alternative embodiment, the areas of junctions can be connected. Then, the
absorbent
material can be deposited in a discrete pattern, or in other words the
absorbent
material represents islands in a sea of thermoplastic material 420. Hence, a
discontinuous layer of absorbent polymer material 410 may comprise connected
areas
of absorbent polymer material 410 or may comprise discrete areas of absorbent
polymer material 410.
In a further aspect of the present invention, it has been found that absorbent
cores providing for a good wet immobilization can be formed by combining two
layers. In this embodiment, the absorbent core material comprises two
substrate
layers 400, two layers of absorbent polymer material 410 and two layers of
fibrous
thermoplastic materials 420. When two discontinuous layers of an absorbent
polymer
material 410 are used, they would be typically arranged in such a way that the
absorbent polymer material of the one layer faces the areas of junction 440 of
the
other layer. In an alternative preferred embodiment, however, the areas of
junction
440 are offset and do not face each other.
According to the present invention, the thermoplastic layer 420 can comprise
any thermoplastic composition, preferred are adhesive thermoplastic
compositions,
also referred to as hot melt adhesives. A variety of thermoplastic
compositions are
suitable to immobilize absorbent material. Some initially thermoplastic
materials may
later lose their thermoplasticity due to a curing step, e.g., initiated via
heat, UV
radiation, electron beam exposure or moisture or other means of curing,
leading to the
irreversible formation of a crosslinked network of covalent bonds. Those
materials
CA 02583440 2007-03-30
having lost their initial thermoplastic behaviour are herein also understood
as
thermoplastic materials 420.
Embodiments of the present invention may also include pockets for receiving
and containing waste, spacers which provide voids for waste, barriers for
limiting the
5 movement of waste in the article, compartments or voids which accept and
contain
waste materials deposited in the pull-on garment, and the like, or any
combinations
thereof. Examples of pockets and spacers for use in absorbent products are
described
in U.S. Patent No. 5,514,121; U.S. Patent No. 5,171,236; U.S. Patent No.
5,397,318;
U.S. Patent No. 5,540,671; U.S. Patent No. 6,168,584; U.S. Patent No.
5,306,266; and
10 U.S. Patent No. 5,997,520. Examples of compartments or voids in an
absorbent
article are disclosed in U.S. Patent No. 4,968,312; U.S. Patent No. 4,990,147;
U.S.
Patent No. 5,062,840; and U.S. Patent No. 5,269,755. Examples of suitable
transverse barriers are described in U.S. Patent No. 5,554,142; PCT Patent WO
94/14395; and U.S. Patent No. 5,653,703. Examples of other structures suitable
for
15 management of low viscosity feces are disclosed in U.S. Patent No.
5,941,864; U.S.
Patent No. 5,977,430; and U.S. Patent No. 6,013,063.
While some of the individual features of some of the embodiments of the
present invention have been known in the art, even greater benefits in urinary
toilet
training than those previously seen are possible using the combinations of
elements
20 described herein. Additionally, using some of the related features
described can lead
to even greater synergistic benefits. For example, refastenable fasteners with
easy
open tabs and the sensory elements described with active graphics can provide
an
article which a child may easily apply, check, remove (including when
urination is
imminent) and provides multiple sensory based feedback signals (such as
visible
25 graphics, tactile sensation members, etc.). Such features re-enforce each
other in
ways previously not combined in the art.
As stated previously, the sensory element member of the present invention can
provide a wetness signal, a temperature change signal, or a combination
thereof. For
example, a portion of the liquid absorbed by the wetness sensation member can
30 partially evaporate thereby causing a cooling sensation for the wearer. The
outer
cover 62 of the absorbent article, may include a substantially vapor permeable
CA 02583440 2007-03-30
46
material. The outer cover 62 is generally constructed to be permeable to at
least water
vapor and has a moisture vapor transmission rate of at least 1000 g/m2/24 hr,
preferably at least 2000 g/m2/24 hr, more preferably at least 3000 g/m2/24
hr., even
more preferably at least 3500 g/m2/24 hr, most preferably at least 4000
g/m2/24 hr and
even most preferably at least 4500 g/m2/24 hr. For example, the outer cover 62
may
define a moisture vapor transmission rate of from 1000 to 10000 g/m2/24 hr or
any
value within the range. Materials which have a moisture vapor transmission
rate less
than those above may not allow a sufficient amount of air exchange and
undesirably
result in increased levels of humidity of the air inside the article during
use. Some
breathable backsheet materials are described in greater detail in PCT
Application No.
WO 95/16746; U.S. Patent No. 5,938,648; U.S. Patent No. 5,865,823; and U.S.
Patent
No. 5,571,096. Other suitable exemplary materials and a suitable test method
for
measuring the MVTR is described in U.S. Patent 6,448,467.
CA 02583440 2007-03-30
47
Measurement Methods
Temperature Change Response Measurement
Equipment
USB Data Acquisition System, OMB-DAQ-55 with Personal DAQView software
from Omega Engineering Inc
Thermocouples -K type thermocouple, with a 6" long, 0.020" diameter,
stainless steel sheath, ending in a exposed junction. (Part
Number - KMTSS-020E-6) from Omega Engineering Inc.
Computer Suitable computer capable of running Personal DAQView
Software.
Saline 0.9% Saline heated to 37 C +/- 1 C
Syringe Capacity of at least 75 mL
Timer Convenient Source, time measurements taken to nearest
second
Curved Plate A U-shaped Plexiglas plate to mount the test product on
in a curved configuration. A suitable plate is 5mm thick,
Radius of Curvature of the U-portion is 250mm, Height
(upright walls from bottom of "U") is 160 mm, Width is
130 mm. The curved plate may be supported with side
walls or other convenient mechanism to maintain upright,
U-shaped disposition
Test Procedure
1. Test fluid is 0.9 % saline heated to 37 C +/- 1 C.
2. If the product is provided in a closed, pant-like form, open side seams of
all
products. If product contains defined side seams product should be opened at
CA 02583440 2007-03-30
48
those locations. Otherwise, cut side panels with scissors at midpoint of side
panels.
3. Mount the test product onto the curved plate. Any suitable mechanism may be
used. Two sided adhesive strips or hook material with the hooks facing the
inside of the "U" may be used for this purpose depending upon the surface
properties of the outer cover of the test product. (An example of hook
material is supplied by Velcro USA Inc., Manchester, NH 03108). Typical
hook or adhesive mounting strip are 520 mm long and 10 mm to 30 mm wide.
Each strip is placed parallel to, and between 30mm and 40mm away from,
with a strip on either side of the longitudinal center line of the template.
The
hook strips allow the continuous attachment of the test product to the
template.
The product is attached to the template such that the topsheet is facing away
from the template (i.e. toward the space defined by the inside of the "U").
Pant elastics should stay intact.
4. The thermocouples are affixed on the surface using strips of masking tape 5
to
6 mm in width and 20 to 40 mm long. The closest tape is positioned such that
the thermocouple tip is exposed and the longitudinal edge of the tape strip is
between 4 to 6 mm from the thermocouple tip. This tape is then used to attach
the thermocouple on the surface to be measured such that the tip of the
thermocouple is positioned no higher than lmm above said surface. More
strips (generally less than 3) can be used to secure the remainder of the
thermocouple.
5. Measure as follows to define the loading point
a. (boy) 102cm below front edge of the core, or
b. (girl) 12.7cm below front edge of the core.
c. (unisex or generic ) use boy product measurement for loading point
6. Draw 75 mis of 0.9 saline (heated to 37 C -+/- 1 C) into syringe.
CA 02583440 2007-03-30
49
7. Temperature measurement is started between 5 to 15 seconds before the
introduction of fluid and continues for at least the next 600 seconds.
8. Using syringe, deposit the saline at the loading point with a constant rate
of
loading. Loading should be done over approximately 5 seconds or at
approximately 15 mL/second.
9. Once fluid is deposited, start timer. Depositing of the fluid is considered
to be
the "urination event" for comparison of time with time parameters in the
claims.
10. Data is collected via the OMB-DAQ-55 system and stored in the computer in
a predetermined folder, in various forms. One common for is an ASCII text
file which is easily exported to common spreadsheet software (Excel) for
further analysis.
11. Using generated data determine AT (taking 37 C as T ) at 30 seconds from
start of timer (urination event).
12. Using generated data determine cooling rates (AT/second, taking 37W as To,
and deposit of fluid as to) at the following intervals, 0 to 3 seconds, 3 to
10
seconds and 10 to 30 seconds from To.
13. Using generated data determine Tmin for 600 second interval. Determine
ATmax defined as 37 C - Tm;n. Duration of temperature change response is
considered to be time at which thermocouple temperature is Tmin +25 % ATm .
Wetness Density Test
Purpose
This test simulates the introduction of urine into a training pant diaper. No
pressure is applied while loading to simulate the baby urinating in a standing
position.
CA 02583440 2007-03-30
Equipment
Template Flat Base unit on which to mount the test product
Filter Paper Ahlstrom Filtration Paper Code 632, 127 x 127 mm
Balance accuracy -H- 0.01 g
5 Saline 0.9% Saline heated to 37 C 41-1 C
Graduated Cylinder Convenient Source
Timer Convenient Source, time measurements taken to nearest
second
Weight Plastic Dimensions/Weight 127 X 127 mm, 297 grams
10 Metal Cylinder Metal Cylinder, Inside Diameter60 mm, Outside
Diameter=70 mm, Height=40 mm, Weight=327 grams.
Test Procedure
1. Test fluid is 0.9% saline heated to 37 C -+/- 1 C.
2. If the product is provided in a closed, pant-like form, open side seams of
all
15 products. If product contains defined side seams product should be opened
at
those locations. Otherwise, cut side panels with scissors at midpoint of side
panels.
3. Mount the test product with clamps onto a flat template in a flat stretched
out
condition to ensure no wrinkles in the topsheet or liners. The pant elastics
20 should stay intact.
4. Weigh one piece of filter paper.
5. Measure as follows to define the loading point
(boy) 10.2 cm below front edge of the core, or
CA 02583440 2009-11-26
51
(girl) 12.7 cm below front edge of the core.
(unisex or generic) use boy loading point measurement
6. Measure 75 mis of 0.9 saline (heated to 37 C +/- 1 C) into the graduated
cylinder.
7. Center the cylinder over the loading point and pour the saline from the
graduated cylinder at the loading point. Loading should be done over
approximately 5 seconds or at approximately 15 mL/second.
8. Once fluid is poured, start timer. Pouring the saline is considered to be
the
"urination event" for purposes of comparison of time with time parameters in
the claims.
9. After 60 seconds have elapsed, place filter paper on the topsheet and then
the
plastic weight to ensure complete contact between the filter paper and the
topsheet. The weight should be lowered slowly and applied gently to the filter
paper.
10. After 10 seconds from weight application, lift the weight and filter paper
off of
the topsheet and weigh the filter paper.
11. Calculate wet weight minus dry filter paper weight in mg. This value is
divided by 161.29 cm2 to determine the wetness density in mg/cm2.
All documents cited in the Detailed Description are not to be construed as an
admission that it is prior art with respect to the present invention.
While particular embodiments 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. It is therefore intended to cover in the appended claims all
such
changes and modifications that are within the scope of this invention.
CA 02583440 2007-03-30
52
The dimensions and values disclosed herein are not to be understood as being
strictly limited to the exact numerical values recited. Instead, unless
otherwise
specified, each such dimension is intended to mean both the recited value and
a
functionally equivalent range surrounding that value. For example, a dimension
disclosed as "40 mm" is intended to mean "about 40 mm".
