Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DISPOSABLE PULL-ON GARMENT
FIELD OF THE INVENTION
The present invention relates to disposable pull-on garments which are donned
by inserting
the wearer's legs into the leg openings and sliding the garment up into
position about the lower
torso.
BACKGROUND OF THE INVENTION
Infants and other incontinent individuals wear disposable absorbent articles
such as diapers
to receive and contain urine and other body exudates. Absorbent garments
having fixed sides (e.g.,
training pants or pull-on diapers) have become popular for use on children
able to walk and often
who are toilet training. In order to contain body exudates as well as to fit a
wide variety of body
shapes and sizes, these pants must fit snugly about the waist and legs of the
wearer without
drooping, sagging or sliding down from its position on the torso
Many pull-on diapers use elastic elements secured in an elastically
contractible condition in
the waist and leg openings. Typically, in order to insure full elastic fit
about the leg and the waist
such as is provided with durable undergarments, the leg openings and waist
opening are encircled
with elasticized bands of rubber or other materials positioned along the curve
of the opening.
Examples of such pull-on diapers are disclosed in EP 1 1S4 012 A1 published on
March 6, 2002.
The pull-on diaper disclosed therein comprises an absorbent body and an
exterior member covering
the absorbent body and forming a contour of the diaper. The absorbent body is
substantially
rectangular and comprises a liquid-permeable topsheet, a liquid-impermeable
backsheet and an
absorbent core interposed therebetween. The leg and waist elastic members are
installed into the
exterior member to form an elasticized leg opening and an elasticized waist
opening. The leg and
waist elastic members should be securely held in a right position of the
diaper so that they provide
an expected elasticity function around the leg and waist openings. Therefore,
the exterior member is
formed with two layers comprising an inner layer and an outer layer to hold
the leg and waist elastic
members therebetween so that the two layers sandwich the leg and waist elastic
materials. Although
such a pull-on diaper may allow to hold the elastic members in a right
position of the diaper, the
diaper is bulky and costly because the exterior member is formed with two
layers. Especially such a
diaper which is bulky in the crotch region is problematic because the bulky
material of the crotch
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region inhibits movementlcontraction of leg elastic member and deteriorates
fitment about the leg
opening and also gives the wearer a stiffish impression and uncomfortableness
when in use.
Another example of pull-on diapers is disclosed in Japanese Laid-open
Publication No. H4-
144558 published on May 19, 1992. The pull-on diaper disclosed therein
comprises an absorbent
main body and an elastic belt joint to the front region and the back region of
the absorbent main
body. The elastic belt provides elasticity to hold the diaper on the wearer.
The elastic belt is
provided to only cover the wearer's waist portion but does not extend into the
crotch region of the
diaper. This structure lacks an exterior member covering the crotch region of
the absorbent main
body. Due to the lack of the exterior member, the leg elastic member must be
installed into the
longitudinal edge of the main absorbent body such that the leg elastic member
is interposed between
the topsheet and the backsheet. However, such a structure easily causes a
leakage problem because
the topsheet which typically allows body fluid to wick therethrough extends to
the longitudinal edge
of the main body.
Based on the foregoing, there is a need for a disposable pull-on garment
having a less bulky
crotch portion while reducing a leakage problem through the crotch opening.
None of the existing
disposable pull-on garment provides all of the advantages and benefits of the
present invention.
SUMMARY OF THE INVENTION
The present invention is directed to a disposable pull-on garment. The
disposable pull-on
garment has a waist opening and leg openings. The pull-on garment comprises an
absorbent main
body, a ring-like elastic belt and an outer cover layer. The absorbent main
body comprises a liquid
pervious topsheet, a liquid impervious backsheet and an absorbent core
disposed therebetween. The
absobent main body has a longitudinal centerline, longitudinal side edges,
transverse end edges, a
front waist region, a back waist region and a crotch region. The front waist
region and the back
waist region are not joined directly. The ring-like elastic belt comprises a
front belt layer and a back
belt layer. The ring-like elastic belt is joined to the absorbent main body at
the front waist region
and the back waist region to form one waist opening and two leg openings. The
ring-like elastic belt
is not disposed in the crotch region of the absorbent main body. The outer
cover layer comprises a
separate material from the front belt layer and the back belt layer. The outer
cover layer has
longitudinal side portions and transverse end portions. The outer cover layer
covers the absorbent
main body in the crotch region and extends into the front waist region and the
back waist region to
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be joined with the ring-like elastic belt. The longitudinal side portion of
the outer cover layer is
provided with a leg elastic material to form an elastic leg cuff.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and
distinctly
claiming the subject matter which is regarded as forming the present
invention, it is believed that the
invention will be better understood from the following description which is
taken in conjunction
with the accompanying drawings and which like designations are used to
designate substantially
identical elements, and in which:
Figure 1 is a perspective view of the disposable pull-on garment of the
present invention in
a typical in-use configuration;
Figure 2 is a top plan view of the pull-on garment in its flat uncontracted
condition showing
the inner surface;
Figure 3 is a cross-sectional view of Figure 2 taken along the line III-III;
Figure 4 is a cross-sectional view of Figure 2 taken along the line IV-IV;
Figure 5 is a cross-sectional view of Figure 2 taken along the line V-V;
Figure 6 is a schematic perspective view of the outer cover layer in a typical
in-use
configuration without showing other elements of the pull-on garment;
Figure 7 is a schematic top plan view of the outer cover layer of the
conventional pull-on
garment without showing an absorbent main body;
Figure 8 is a schematic cross-sectional view of Figure 7 taken along the
longitudinal
centerline L;
Figure 9 is a schematic top plan view of the combination of the ring-like
elastic belt and the
outer cover layer without showing an absorbent man body;
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Figure 10 is a schematic cross-sectional view of Figure 9 taken along the
longitudinal
centerline L;
Figure 11 is a cross-sectional view showing a typical in-use configuration of
the portion
shown in Figure 3;
Figure 12 is a top plan view of the pull-on garment in its flat uncontracted
condition
showing the outer surface;
Figure 13 is a schematic view showing the process for forming the pull-on
garment shown
in Figure 1; and
Figure 14 is an alternative embodiment of the belt forming section in the
process for
forming the pull-on garment.
DETAILED DESCRIPTION OF THE 1NVENTION
As used herein, the term "pull-on garment" refers to articles of wear which
have a defined
waist opening and a pair of leg openings and which are pulled onto the body of
the wearer by
inserting the legs into the leg openings and pulling the article up over the
waist. The term
"disposable" is used herein to describe garments which are not intended to be
laundered or
otherwise restored or reused as a garment (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 pull-on garment is also preferably "absorbent" to
absorb and contain the
various exudates discharged from the body. A preferred embodiment of the pull-
on garment of the
present invention is the disposable absorbent pull-on garment, pull-on diaper
20, shown in Figure 1.
As used herein, the term "pull-on diaper" refers to pull-on garments generally
worn by infants and
other incontinent individuals to absorb and contain urine and feces. It should
be understood,
however, that the present invention is also applicable to other pull-on
garments such as training
pants, incontinent briefs, feminine hygiene garments or panties, and the like.
Figure 1 is a perspective view of the pull-on diaper 20 of the present
invention. The pull-
on diaper 20 has an outer surface 22, an inner surface 24 opposed to the outer
surface 22, a front
region 26, a back region 28, a crotch region 30, and seams 32 which join the
front region 26 and the
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back region 28 to form leg openings 34 and a waist opening 36. The diaper 20
comprises an
absorbent main body 38 (hereinafter may be referred to as "main body") to
cover the crotch region
of the wearer, a ring-like elastic belt 40 (hereinafter may be referred to as
"elastic belt" or "belt")
extending transversely about the waist opening 36, and an outer cover layer 42
to cover the main
body 38. The elastic belt 40 defines the waist opening 36, and the elastic
belt 40 and the main body
38 jointly defines the leg opening 34. The pull-on diaper 20 also has a patch
sheet 44 printed with a
graphic 46 thereon which may be disposed in the front region 26 and/or the
back region 28.
The absorbent main body 38 absorbs and contains body exudates disposed on the
main body
38. In the embodiment shown in Figure 2, the main body 38 has a generally
rectangular shape
having a longitudinal centerline L, longitudinal side edges 48 and transverse
end edges 50. The
main body 38 also has a front waist panel 52 positioned in the front waist
region 26 of the diaper 20,
a back waist panel 54 positioned in the back waist region 28, and a crotch
panel 56 in the crotch
region 30.
The main body 38 comprises a liquid pervious topsheet 58, a liquid impervious
backsheet
60 and an absorbent core 62 disposed therebetween. The main body 38 may
additionally comprise a
barrier leg cuff 64 disposed along the longitudinal side edge 48. The barrier
leg cuff 64 provides
improved containment of liquids and other body exudates in the crotch region
30. The barrier leg
cuff 64 shown in Figure 3 comprises a single layer of material which is folded
into two layers. The
barrier leg cuff 64 extends from the longitudinal side edge 48 toward the
longitudinal centerline L
and then is folded along the folding line 66 back toward the longitudinal side
edge 48. The barrier
leg cuff 64 has an barrier cuff elastic material 72 at the distal edge 68. The
proximal edge 70 of the
barrier leg cuff 64 is joined to the backsheet 60 adjacent the longitudinal
side edge 48. The portion
of the barrier leg cuff 64 along the folding line 66 and the distal edge 68
are free from attachment to .
any portion of the main body 38 in the crotch panel 56 such that the barrier
leg cuff 64 stands up
toward the wearer's body when the diaper 20 is used. The transverse end 74 of
the barrier leg cuff
64 is joined to the topsheet 58 adjacent the folding line 66 by an attachment
means 76 such as an
adhesive and is joined to the barrier leg cuff 64 itself along the distal edge
68 by an attachment
means 78 as shown in Figure 4.
The liquid pervious topsheet 58 is preferably positioned adjacent the body-
facing surface of
the absorbent core 62 and may be joined thereto and/or to the backsheet 60 by
any attachment means
known in the art. The topsheet 58 is preferably compliant, soft feeling, and
non-irritating to the
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wearer's skin. Further, at least a portion of the topsheet 58 is liquid
pervious, permitting liquid to
readily penetrate through its thickness. A suitable topsheet 58 may be
manufactured from a wide
range of materials, such as porous foams; reticulated foams; apertured plastic
films; or woven or
nonwoven webs of natural fibers (e.g., wood or cotton fibers), synthetic
fibers (e.g., polyester or
polypropylene fibers), or a combination of natural and synthetic fibers.
Preferably, the topsheet 58
is made of a hydrophobic material or is treated to be hydrophobic in order to
isolate the wearer's
skin from liquids contained in the absorbent core 62. If the topsheet 58 is
made of a hydrophobic
material, preferably at least the upper surface of the topsheet 58 is treated
to be hydrophilic so that
liquids will transfer through the topsheet more rapidly.
The liquid impervious backsheet 60 is generally that portion of the diaper 20
positioned
adjacent the garment-facing surface of the absorbent core 62. The backsheet 60
prevents the
exudates absorbed and contained therein from soiling articles that may contact
the diaper 20, such as
bedsheets and undergarments. In preferred embodiments, the backsheet 60 is
impervious to liquids
(e.g., urine) and comprises a thin plastic film. Suitable backsheet materials
may include breathable
materials that permit vapors to escape from the diaper 20 while still
preventing exudates from
passing through the backsheet 60.
The absorbent core 62 may comprise any absorbent material that is generally
compressible,
conformable, non-irritating to the wearer's skin, and capable of absorbing and
retaining liquids such
as urine and other certain body exudates. The absorbent core 62 can be
manufactured in a wide
variety of sizes and shapes (e.g., rectangular, hourglass, "T"-shaped,
asymmetric, etc.) and may
comprise a wide variety of liquid-absorbent materials commonly used in
disposable diapers and
other absorbent articles such as comminuted wood pulp, which is generally
referred to as airfelt.
Examples of other suitable absorbent materials include creped cellulose
wadding; meltblown
polymers, including coform; chemically stiffened, modified or cross-linked
cellulosic fibers; tissue,
including tissue wraps and tissue laminates; absorbent foams; absorbent
sponges; superabsorbent
polymers; absorbent gelling materials; or any other known absorbent material
or combinations of
materials. The configuration and construction of the absorbent core 62 may
also be varied (e.g., the
absorbent cores) or other absorbent structures) may have varying caliper
zones, a hydrophilic
gradient, a superabsorbent gradient, or lower average density and lower
average basis weight
acquisition zones; or may comprise one or more layers or structures).
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The ring-like elastic belt 40 extends transversely about the waist opening 36
of the diaper 20
and acts to dynamically create fitment forces and to distribute the forces
dynamically generated
during wear. The elastic belt 40 comprises a front belt 84 and a back belt 86
(hereinafter may be
referred to as "front and back belt 84, 86) which are joined at the seam 32 to
form a pull-on diaper
having a waist opening and two leg openings. Each of the front belt 84 and the
back belt 86 has a
central panel 80 and side panels 82 positioned transversely outward from the
central panel 80. Each
of the front belt 84 and the back belt 86 also has a transverse waist border
88 and a transverse
abdomen border 90. The transverse waist border 88 defines the waist opening
36. The central panel
40 of the front belt 84 may partly or entirely overlap with the front waist
panel 52 of the main body
38. The central panel 40 of the back panel 86 may partly or entirely overlap
with the back waist
panel 54 of the main body 38. However, the central panel 40 of the front and
back panel 84, 86
does not extend into the crotch panel 56 of the main body 38 and is not
disposed in the crotch panel
56. In the embodiment shown in Figure 2, the central panel 40 of the front
belt 84 and the back belt
86 partly overlap with the front waist panel 52 and the back waist panel 54,
respectively.
The ring-like elastic belt 40 comprises an outer layer 92. The elastic belt 40
further
comprises an inner layer 94 and a belt elastic material 96 interposed between
the outer layer 92 and
the inner layer 94. The front belt 84 and the back belt 86 may comprise the
same materials and/or
may have the same structure. Alternatively, the front belt 84 and the back
belt 86 may comprise
different materials and/or may have different structures. As shown in the
embodiment of Figure 2,
the front belt 84 and the back belt 86 generally have the same structure.
Referring to Figure 5, the
inner layer 94 has a transverse waist edge 104 and a transverse abdomen edge
106. The outer layer
92 has a transverse waist end 108 and a transverse abdomen end 110. The inner
layer 94 is almost
coextensive with the contour of the front and back belt 84, 86. Alternatively,
the inner layer 94 may
be smaller than the size of the front and back belt 84, 86. The outer layer 92
is longer than the size
of the inner layer 94 in the longitudinal direction and an end flap 112 of the
outer layer 92 is folded
to cover the transverse waist edge 104 of the inner layer 94 at the waist
opening 36 and to form a
transverse waist end 108 of the outer layer 92. The inner layer 94 may also
have an end flap which
may be folded together with the end flap 112 of the outer layer 92. The end
flap of the inner layer
94 may be longer or shorter than or equal to the end flap of the outer layer
92. Alternatively, the
end flap 112 may be eliminated such that the outer layer terminates at the
waist opening 36 to form
a transverse waist end 108. In the embodiment shown in Figures 2 and 5, the
transverse waist end
108 and the transverse abdomen end 110 of the outer layer 92 correspond to the
transverse waist
border 88 and the transverse abdomen border 90 of the front and back belt 84,
86, respectively. The
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outer layer 94 surrounded by the transverse waist end 108 and the transverse
abdomen end 110
defines the. shape of the front and back belt 84, 86 in the embodiment shown
in Figures 2 and 5.
The front and back belt 84, 86 may have any shape to provide a ring-like belt
when the front
belt 84 and the back belt 86 are joined at the seam 32. In the embodiment
shown in Figure 2, the
transverse abdomen border 90 may be shaped such that the longitudinal length A
between the
transverse waist border 88 and the transverse abdomen border 90 in the central
panel 80 is longer
than the longitudinal length B between the transverse waist border 88 and the
transverse abdomen
border 90 in the side panel 82. Alternatively, the transverse abdomen border
90 may be straight
such that the longitudinal length A and B may be the same in the central panel
and in the side panel.
Further, the transverse abdomen border 90 may be shaped such that the
longitudinal length A may
be shorter than the longitudinal length B.
The front and back belt 84, 86 may comprise any known materials. Suitable
material for the
front and back belt 84, 86 can be manufactured from a wide range of materials
such as plastic films;
apertured plastic elms; woven or nonwoven webs of natural materials (e.g.,
wood or cotton fibers),
synthetic fibers (e.g., polyolefins, polyamides, polyester, polyethylene, or
polypropylene fibers), or
a combination of natural and/or synthetic fibers; or coated woven or nonwoven
webs. Preferably
the belt comprises a nonwoven web of synthetic fibers. The belt may comprise a
stretchable
nonwoven. More preferably, the belt comprises an inner hydrophobic, non-
stretchable nonwoven
material and an outer hydrophobic, non-stretchable nonwoven material.
The belt elastic material 96 comprises a waist elastic material 98 and a side
elastic material
100. The waist elastic material 98 may comprise one or more of elastic
elements such as strands or
panels extending in the transverse direction. The side elastic material 100
also may comprise one or
more of elastic elements such as strands or panels extending in the transverse
direction. The waist
elastic material 98 is continuously disposed along the transverse waist border
88 of the front and
back belt 84, 86. The side elastic material 100 is preferably disposed in the
side panel 82 of the
front and back belt 84, 86. In the embodiment shown in Figure 2, the waist
elastic material 98 and
the side elastic material 100 comprise a plurality of elastic strands which
are disposed at a constant
interval in the longitudinal direction. Alternatively, the waist elastic
material 98 and the side elastic
material 100 may be disposed at a different interval in the longitudinal
direction. No elastic material
may be provided in a portion of the central panel 80 of the front and back
belt 84, 86 which overlaps
with the absorbent core 62, preferably with the front and back waist panel 52,
54 of the main body
38. Alternatively, no elastic material may be provided in the entirety of the
central panel 80.
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However, an elastic material may be provided in the central panel 80 if it is
necessary. The belt
elastic material 96 is interposed between the outer layer 92 and the inner
layer 94 and joined
therebetween in a stretched condition of the belt elastic material 96 such
that the front and back belt
84, 86 provides elasticity when the diaper 20 is used.
The outer cover layer 42 is disposed on the outer surface 22 of the diaper 20
and covers the
crotch panel 56 of the absorbent main body 38. The outer cover layer 42 has a
generally rectangular
shape having longitudinal side portions 114 and transverse end portions 116
(refer to Figure 5 as
well). The longitudinal side portions 114 extends transversely outward beyond
the longitudinal side
edge 48 of the main body 38. The longitudinal side portion 114 is provided
with a leg elastic
material 118 to form an elastic leg cuff 122. The leg elastic material 118 is
disposed so as to extend
generally longitudinally along the longitudinal side portion 114. However, the
leg elastic material
118 may be disposed at least in the crotch region 30 of the diaper 20 and may
n'ot be disposed along
the entirety of the longitudinal side portion 114. In order to form the
elastic leg cuff 122 in the
embodiment, the longitudinal side portion 114 is folded to form a sleeve 120
to encase the leg
elastic material 118 as shown in Figure 3. The transverse end portion 116A
along the longitudinal
side portion 114 is folded toward the longitudinal centerline L of the main
body 38 and tacked down
in the folded configuration by any known means such as adhesives, heat
bonding, pressure bonding,
ultrasonic bonding, etc. The transverse end portion 116A is preferably folded
outwardly so as to be
away from the liquid impervious backsheet 60 of the main body 38 and is joined
onto itself by a
bonding means 120 to maintain its folded configuration (refer to Figures 4 and
6). However, the
longitudinal side portion 114 in the crotch region 30 is free from attachment
(refer to Figures 3 and
6) such that the longitudinal side portion 114 serves as the elastic leg cuff
122 when the diaper 20 is
used. Alternatively, the transverse end portion 116A may be folded inwardly
onto the topsheet side
of the main body 38.
The outer cover layer 42 comprises a material separate from the material of
the inner layer
94 and the outer layer 92 constituting the elastic belt 40. Alternatively, the
outer cover layer 42 may
comprise two of more layer of materials. The outer cover layer 42 may comprise
any known
materials. Suitable material for the outer cover layer 42 can be manufactured
from a wide range of
materials such as plastic films; apertured plastic films; woven or nonwoven
webs of natural
materials (e.g., wood or cotton fibers), synthetic fibers (e.g., polyolefins,
polyamides, polyester,
polyethylene, or polypropylene fibers), or a combination of natural and/or
synthetic fibers; or coated
woven or nonwoven webs. Preferably the outer cover layer 42 comprises a single
layer of
nonwoven web of synthetic fibers. More preferably, the outer cover layer 42
comprises a single
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layer of hydrophobic, non-stretchable nonwoven material. Further, the outer
cover layer 42 may
comprise the same material composition as the inner layer 94 and the outer
layer 92 of the elastic
belt 40.
The outer cover layer 42 covers the crotch panel 56 of the absorbent main body
38. The
outer cover layer 42 may extend into and cover the front waist panel 52 and
the back waist panel 54
of the main body 38. The outer cover layer 42 is directly joined to and covers
the liquid impervious
backsheet 42 of the main body 38. In the configuration where the transverse
end portion 116A
along the longitudinal side portion 114 is folded outwardly so as to be away
from the liquid
impervious backsheet 60 of the main body and joined onto itself by the bonding
means 120, the
central panel 80 of the front and back belt 84, 86 is joined to the front
waist panel 52 and the back
waist panel 54 of the main body 38 through the outer cover layer 42. Thus, the
outer cover layer 42
is sandwiched between the front and back belt 84, 86 and liquid impervious
backsheet 60 of the
main body 38. The transverse end portion 116A tacked down is hidden underneath
the front and
back belt 84, 86. The front belt 84 and the back belt 86 are joined at the
seam 32 to form the ring-
like elastic belt 40. However, the front waist panel 52 and the back waist
panel 54 are not directly
joined along the longitudinal side edges 48 but are only indirectly joined
through the front and back
belt 84, 86.
Figure 7 shows a schematic top plan view of an outer cover or an exterior
member of a
conventional pull-on diaper without showing an absorbent main body. Figure 8
is a schematic
cross-sectional view of Figure 7 taken along the longitudinal centerline L.
The outer cover 200 is
typically coextensive with the contour of the diaper to form a diaper shape
and contains an
absorbent main body inside. The outer cover 200 has another function which is
to hold elastic
materials (such as waist elastic material 202, side elastic material 204 and
leg elastic material 206)
which create fitment forces. In order to hold the elastic materials, the outer
cover 200 typically
comprises two layers of nonwoven to sandwich and anchor the elastic materials.
However, such a
structure makes the diaper costly because the outer cover 200 must comprise
two layers even in the
crotch region. It also makes the crotch region of the diaper makes bulky to
inhibit
movementlcontraction of leg elastic member and deteriorates fitment about the
leg opening.
Figure 9 shows a schematic top plan view of a combination of a ring-like
elastic belt and an
outer cover layer of the present invention without showing an absorbent main
body. Figure 10 is a
schematic cross-sectional view of Figure 9 taken along the longitudinal
centerline L. The front and
back belt 84, 86 of the ring-like elastic belt 40 comprises two layers of
nonwoven to hold the belt
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elastic materials 96. However, the ring-like elastic belt 40 formed with two
layers of nonwoven
(inner layer 94 and outer layer 92) does not extend into the crotch region 30
of the diaper. Instead,
the outer cover layer 42 comprising a single layer of nonwoven is disposed in
the crotch region 30.
This structure is less costly, allows the crotch region 30 of the diaper to be
less bulky and eliminates
various drawbacks of conventional pull-on diaper. The outer cover layer 42
comprising a nonwoven
material also provides a cloth-like appearance together with the ring-like
elastic belt 40 comprising a
nonwoven material. The outer cover layer 30 is formed with a separate material
from the material
of the inner layer 94 and the outer layer 92. Therefore, the longitudinal side
portion 114 of the outer
cover layer 42 can be folded along the longitudinal direction to form the
elastic leg cuff 122 or the
transverse end portion 116A along the longitudinal side portion 114 can be
tacked down as
explained above without being interfered by the front and back belt 84, 86.
Such folding can be
done before the outer cover layer 42 and the front and back belt 84, 86 are
joined to one another.
The elastic leg cuff 122 formed by the longitudinal side portion 114 extends
transversely outward
beyond the longitudinal side edge 48 of the main body 38. The elastic leg cuff
122 stands up and
covers the longitudinal side edge 48 to reduce leakage from the main body 38
when the diaper 20 is
used (refer to Figure 11 ). Further, the transverse end portion 116A which is
outwardly folded and
tacked down in its folded configuration ensures the elastic leg cuff 122 to
stand up securely in the
crotch region 30 (refer to Figure 6 showing a schematic perspective view of
the outer cover layer 42
in a typical in-use configuration without showing other elements of diaper
20).
The front and back belt 84, 86 has the shaped transverse abdomen border 90 as
explained
above. The central panel 80 has the longitudinal length A longer than the
longitudinal length B in
the side panel 82. This increases the joint area between the central panel 80
and the outer cover
layer 42 to enhance the joint strength between the outer cover layer 42 and
the central panel 80 of
the front and back belt 84, 86. On the other hand, the longitudinal length B
in the side panel 82
being shorter than the longitudinal length A allows to form leg openings with
a greater
circumference for providing comfortableness to the wearer.
The patch sheet 44 printed with a graphic 46 is provided on the diaper 20 to
provide an
aesthetic appearance. The graphic 46 may be any graphic to increase aesthetic
appearance, such as
visual characters, educational signs or marks. The patch sheet 44 may comprise
any known material
such as a plastic film, a woven, a nonwoven or tissues and may have any shape.
The patch sheet 44
may also comprise a single sheet or two or more separate sheets. In the
embodiment shown in
Figure 12, the patch sheet 44 comprises a single rectangular nonwoven having
high breathability.
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The printing may be made by any known process such as flexographic printing,
ink jet printing,
screen printing, or rotogravure printing.
The patch sheet 44 is a material separate from any elements constituting the
diaper 20. The
patch sheet 44 may be joined anywhere as far as it can be seen by the user of
the diaper. The patch
sheet 44 is preferably joined somewhere outside the liquid impervious
backsheet 60 of the main
body 38, preferably outside the outer cover layer 42, more preferably outside
the inner layer 94 of
the front and back belt 84, 86 to reduce hazy appearance of the graphic 46.
The patch sheet 44,
however, is joined inside the outer layer 94 of the front and back belt 84, 86
to prevent an ink rub-
off problem caused by abrasion of the ink layer of the graphic 46 with other
substrates such as
cloths or floors. In the embodiment shown in Figure 5, the patch sheet 44 with
the graphic 46 is
disposed and joined between the inner layer 92 and the outer layer 94 of the
front and back belt 84,
86. However, if the front and back belt 84, 86 of the diaper 20 is formed with
only the belt elastic
material 96 and the outer layer 94 and does not have the inner layer 92, the
patch sheet 44 may be
disposed between the liquid impervious backsheet 60 of the main body 38 and
the outer layer 94 of
the front and back belt 84, 86. In such a case, the patch sheet 44 may be
joined to the liquid
impervious backsheet 60, the outer layer 94 or both of them.
The position of the patch sheet 44 is selected such that the patch sheet 44 is
disposed
between the transverse waist end 108 and the transverse abdomen end 110 of the
front and back belt
84, 86. The transverse waist end 108 and the transverse abdomen end 110 do not
cross any portion
of the graphic 46 (refer to Figure 12). The entirety of the graphic 46 is
covered by only the outer
layer 92. Therefore, the graphic appearance is the substantially same anywhere
in the patch sheet 44
not to make a part of the graphic 46 to have hazier appearance than other
parts of the graphic 46.
While the size of the patch sheet 44 may be restricted by the shape of the
front and back belt 84, 86,
the size of the patch sheet 44 is still adjustable by making the transverse
abdomen border 90 (which
corresponds to the transverse abdomen end 110 in the embodiment) of the front
and back belt 84, 86
shaped. The central panel 80 having the longitudinal length A longer than the
longitudinal length B
in the side panel 82 (refer to Figure 2) allows to use the patch sheet 44
having a longer longitudinal
length than a patch sheet installed in the front and back belt having a
straight transverse waist border
and a straight abdomen border.
The patch sheet 44 is preferably disposed in the central panel 80 of the front
and back panel
84, 86 in which the belt elastic material 96 is not present as shown in Figure
12. However, the patch
sheet 44 may be disposed in the area such as in the side panel 82 in which the
belt elastic material
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96 is present. The patch sheet 44 may be coextensive with the outer layer 92
of the front and back
belt 84, 86 such that the patch sheet 44 has the same shape as the outer layer
92. However, it is
preferable that the patch sheet 44 is smaller than the outer layer 92 to
reduce bulkiness of the front
and back belt 84, 86. The front and back belt 84, 86 may have two or more
patch sheets with a
graphic which are disposed between the transverse waist end 108 and the
transverse abdomen end
110 of the front and back belt 84, 86.
Figure 13 shows a schematic view to explain a process for forming the diaper
20. The
process 300 shown in Figure 13 primarily comprises four sections; a main body
forming section 302,
a belt forming section 304, an outer cover layer forming section 306 and an
assembly section 308.
The belt elastic material is not illustrated in Figure 13.
The main body forming process 302 combines elements forming the main body 38
such as
the topsheet 58, the backsheet 60, the absorbent core 62 and the barrier leg
cuff 64 (Figure 13 shows
only the topsheet 58 and the absorbent core 62) such that the absorbent core
62 is sandwiched
between the topsheet 58 and the absorbent core 62. These elements are joined
to each other by any
known means such as adhesives.
The belt forming section 304 combines the outer layer 92, the inner layer 94
and the patch
sheet 44 and cuts the combined web comprising the outer layer 92 and the inner
layer 94 into the
front belt 84 and the back belt 86 along the cut line 310 which corresponds to
the transverse
abdomen border 90 of the front and back belt 84, 86. The patch sheet 44 is
disposed in the front and
back belt 84, 86 alternately in a zigzag configuration as shown in Figure 13
and arranged so that the
patch sheet is positioned in the central panel 80 of the front and back belt
84, 86. The cut line 310 is
shaped such that the transverse abdomen border 90 is also shaped. The
transverse abdomen border
90 protrudes in the central panel 80 compared with the transverse abdomen
border 90 in the side
panel 82. The belt elastic material 96 (not shown in Figure 13) is also joined
between the inner
layer 94 and the outer layer 92. Then the front belt 84 and the back belt 86
are separated from each
other and are phased such that the shaped transverse abdomen borders 90 of the
front and back belt
84, 86 are symmetric with respect to the direction in which the front and back
belt 84, 86 is
forwarded.
The outer cover layer forming section 306 forms the outer cover layer 42
having the elastic
leg cuff 122. The outer cover layer 122 is provided with the leg elastic
material 118 along the
longitudinal side portion 114. The longitudinal side portion 114 is folded as
shown in Figure 13 to
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form the elastic leg cuff 122. After that, the longitudinal side portion 114
is oppositely folded and
the portion corresponding to the transverse end portion 116A is tacked down in
the folded
configuration by the bonding means 120 (refer to Figure 4). The outer cover
layer 42 thus provided
with the elastic leg cuff 122 is joined to the backsheet side of the main body
38 to form the
intermediate assembly 312 comprising the main body 38 and the outer cover
layer 42. The
intermediate assembly 312 is then cut into the individual intermediate
assembly 312. The individual
intermediate assembly 312 is turned by 90 degree and fed into the assembly
section 308.
The assembly section 308 combines the individual intermediate assembly 312
with the front
and back belt 84, 86. The individual intermediate assembly 312 is provided on
the front and back
belt 84, 86 such that the front waist panel 52 and the back waist panel 54 of
the main body 38 is
joined through the outer cover layer 42 to the central panel 80 of the front
and back belt 84, 86,
respectively. After that, the end flap 112 of the front and back belt 84, 86
is folded inwardly along
the transverse waist border 88 to form a continuous diaper assembly 314
comprising the main body
38, the outer cover layer 42 and the front and back belt 84, 86. The
continuous diaper assembly 314
thus formed is cut into each individual diaper 20. The. individual diaper 20
is then folded along the
transverse centerline T in the crotch region and the side panel 82 of the
front and back belt 84, 86 is
joined at the seam 32.
Figure 14 shows an alternative embodiment of the belt forming section. The
belt forming
section 404 combines the outer layer 92, the inner layer 94 and the patch
sheet 444. The patch sheet
444 in Figure 14 is positioned to extend both in the front belt 84 and in the
back belt 86. The
combined web is then cut into the front and belt 84 and the back belt 86 along
the cut line 410
which corresponds to the transverse abdomen border 90 of the front and back
belt 84, 86. The patch
sheet 444 is also cut into the front patch sheet 446 and the back patch sheet
448. The cut line 410 is
straight such that the transverse abdomen border 90 is also straight.
All documents cited in the Detailed Description of the Invention are, are in
relevant part,
incorporated herein by reference; the citation of any document is 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.
