U.S. patent application number 14/844411 was filed with the patent office on 2016-03-17 for absorbent article comprising a topsheet/acquisition layer laminate.
The applicant listed for this patent is The Procter & Gamble Company. Invention is credited to Aniruddha CHATTERJEE, Adrien GRENIER, James T. KNAPMEYER, Jill Marlene ORR, Matthew S. RITTER, Rodrigo ROSATI.
Application Number | 20160074249 14/844411 |
Document ID | / |
Family ID | 54140723 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160074249 |
Kind Code |
A1 |
ROSATI; Rodrigo ; et
al. |
March 17, 2016 |
ABSORBENT ARTICLE COMPRISING A TOPSHEET/ACQUISITION LAYER
LAMINATE
Abstract
An absorbent article for personal hygiene comprises a
longitudinal axis, a transversal axis perpendicular to the
longitudinal axis, a topsheet, an acquisition layer, a backsheet
and an absorbent core. The absorbent core is located between the
topsheet and the backsheet. The absorbent core comprises an
absorbent material. The absorbent material comprises at least 80%
of superabsorbent polymers, up to substantially 100% of
superabsorbent polymers, by total weight of the absorbent material.
The absorbent article comprises a topsheet/acquisition layer
laminate comprising the topsheet and the acquisition layer in a
face to face relationship. The topsheet/acquisition layer laminate
comprises three-dimensional protrusions extending from a plane of
the topsheet/acquisition layer laminate. The topsheet and
acquisition layer are nested together such that a majority of the
three-dimensional protrusions formed in the topsheet coincide with
and fit together with a majority of the three-dimensional
protrusions formed in the acquisition layer.
Inventors: |
ROSATI; Rodrigo; (Frankfurt
Am Main, DE) ; ORR; Jill Marlene; (Liberty Township,
OH) ; KNAPMEYER; James T.; (Cincinnati, OH) ;
CHATTERJEE; Aniruddha; (Kelkheim, DE) ; RITTER;
Matthew S.; (Liberty Township, OH) ; GRENIER;
Adrien; (Frankfurt Am Main, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The Procter & Gamble Company |
Cincinnati |
OH |
US |
|
|
Family ID: |
54140723 |
Appl. No.: |
14/844411 |
Filed: |
September 3, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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62049516 |
Sep 12, 2014 |
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62049521 |
Sep 12, 2014 |
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62049408 |
Sep 12, 2014 |
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62049406 |
Sep 12, 2014 |
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62049404 |
Sep 12, 2014 |
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62049403 |
Sep 12, 2014 |
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62049401 |
Sep 12, 2014 |
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62049397 |
Sep 12, 2014 |
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62049392 |
Sep 12, 2014 |
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62210057 |
Aug 26, 2015 |
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62210005 |
Aug 26, 2015 |
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62210020 |
Aug 26, 2015 |
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62210014 |
Aug 26, 2015 |
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Current U.S.
Class: |
604/378 |
Current CPC
Class: |
A61F 2013/530715
20130101; A61F 2013/5395 20130101; A61F 2013/51377 20130101; A61F
2013/15715 20130101; A61F 13/51394 20130101; A61F 2013/5307
20130101; A61F 13/55105 20130101; A61F 13/55145 20130101; A61F
2013/51147 20130101; A61F 13/51 20130101; A61F 13/535 20130101;
A61F 2013/530175 20130101; A61F 2013/51355 20130101; A61F 13/15203
20130101; A61F 2013/421 20130101; A61F 13/15723 20130101; A61F
13/551 20130101; A61F 2013/15284 20130101; A61F 2013/4587 20130101;
A61F 2013/530131 20130101; A61F 2013/53908 20130101; A61F 13/15699
20130101; A61F 13/51108 20130101; A61F 2013/15365 20130101; A61F
2013/530664 20130101; A61F 2013/51007 20130101; A61F 2013/51092
20130101; A61F 13/537 20130101; A61F 13/536 20130101; A61F
2013/530489 20130101; A61F 13/511 20130101; A61F 13/513 20130101;
A61F 13/55115 20130101; A61F 13/5121 20130101; A61F 2013/51002
20130101; A61F 2013/51023 20130101; A61F 13/45 20130101; A61F
2013/4568 20130101; A61F 2013/53472 20130101; A61F 2013/5386
20130101; A61F 13/15707 20130101; A61F 13/51104 20130101; A61F
2013/427 20130101; A61F 2013/8497 20130101; A61F 13/5116 20130101;
A61F 2013/51026 20130101; A61F 2013/51009 20130101; A61F 13/53
20130101; A61F 2013/15463 20130101; A61F 2013/530007 20130101; A61F
2013/530481 20130101; A61F 13/534 20130101 |
International
Class: |
A61F 13/511 20060101
A61F013/511; A61F 13/53 20060101 A61F013/53; A61F 13/534 20060101
A61F013/534; A61F 13/513 20060101 A61F013/513 |
Claims
1. An absorbent article for personal hygiene comprising: a
longitudinal axis, a transversal axis perpendicular to the
longitudinal axis, a liquid permeable topsheet, an acquisition
layer, an absorbent core, a liquid impermeable backsheet and an
absorbent core, wherein the topsheet and the acquisition layer
comprise fibers; wherein the absorbent core is located between the
topsheet and the backsheet; wherein the absorbent core comprises an
absorbent material; wherein the absorbent material comprises at
least 80% of superabsorbent polymers, up to substantially 100% of
superabsorbent polymers, by total weight of the absorbent material;
the absorbent article further comprises an acquisition layer,
wherein a width of the acquisition layer in a direction parallel to
the transversal axis is less than a width of the topsheet in a
direction parallel to the transversal axis; and a
topsheet/acquisition layer laminate comprising the liquid permeable
topsheet and the acquisition layer in a face to face relationship,
wherein the topsheet/acquisition layer laminate comprises
three-dimensional protrusions extending from a plane of the
topsheet/acquisition layer laminate, wherein the topsheet and the
acquisition layer are nested together such that a majority of the
three-dimensional protrusions formed in the topsheet coincide with
and fit together with a majority of the three-dimensional
protrusions formed in the acquisition layer.
2. The absorbent article of claim 1 wherein the topsheet and
acquisition layer laminate are in an intimate contact with each
other.
3. The absorbent article of claim 1 wherein the absorbent core
comprises a core wrap enclosing the absorbent material, wherein the
core wrap comprises a top side facing the topsheet/acquisition
layer laminate and a bottom side facing the backsheet, and wherein
the absorbent core comprises one or more substantially absorbent
material free area(s) through which a portion of the top side of
the core wrap is attached by one or more core wrap bond(s) to a
portion of the bottom side of the core wrap.
4. The absorbent article of claim 1 wherein the
topsheet/acquisition layer laminate comprises one or more
substantially three-dimensional protrusion free area(s).
5. The absorbent article of claim 4 wherein the at least some one
or more substantially three-dimensional protrusion free area(s) of
the topsheet/acquisition layer laminate coincide with the one or
more substantially absorbent material free area(s) of the absorbent
core.
6. The absorbent article of claim 1 wherein the absorbent article
further comprises a distribution layer comprising a dry-laid
fibrous structure and/or a wet-laid fibrous structure located
between the topsheet/acquisition layer laminate and the
backsheet.
7. The absorbent article of claim 6 wherein a carrier layer is
disposed between the topsheet/acquisition layer laminate and the
dry-laid fibrous structure.
8. The absorbent article of claim 6 wherein a carrier layer is
disposed between the dry-laid fibrous structure and the absorbent
core.
9. The absorbent article of claim 1 wherein the fibers of the
three-dimensional protrusions are generally aligned with one
another to form a tunnel shaped loop.
10. The absorbent article of claim 1 wherein the three-dimensional
protrusions are formed from the fibers of the topsheet and the
acquisition layer, wherein the majority of the three-dimensional
protrusions comprise a base forming an opening, an opposed distal
portion, and one or more side walls between the bases and the
distal portions of the majority of the three-dimensional
protrusions, wherein the base, distal portion and one or more side
walls are formed by fibers such that the majority of the
three-dimensional protrusions has only an opening at the base.
11. The absorbent article of claim 1 wherein the length of the
acquisition layer in a direction parallel to the longitudinal axis
is less or equal to the length of the topsheet in a direction
parallel to the longitudinal axis.
12. The absorbent article of claim 1 wherein one of the topsheet or
acquisition layer of the topsheet/acquisition layer laminate
comprises one or more interruptions in an area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate such that the three-dimensional protrusions of the
respective other non-interrupted topsheet or the acquisition layer
at least partially fit together with the three-dimensional
protrusions of the interrupted topsheet or the interrupted
acquisition layer.
13. The absorbent article of claim 1 wherein the topsheet and
acquisition layer of the topsheet/acquisition layer laminate
comprise one or more interruptions in an area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate and the three-dimensional protrusions of the topsheet
coincide with and fit together with the three-dimensional
protrusions of the acquisition layer, and wherein the interruptions
in the topsheet in the area of the three-dimensional protrusions of
the topsheet/acquisition layer laminate does not coincide with the
interruptions in the acquisition layer in the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate.
Description
RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C.
.sctn.119(e) to U.S. Provisional Patent Application Ser. Nos.
62/049,516 (P&G 13530P), 62/049,521 (P&G 13531PQ),
62/049,408 (P&G CM4137FPQ), 62/049,406 (P&G CM4136FPQ),
62/049,404 (P&G CM4135FPQ), 62/049,403 (P&G CM4134FPQ),
62/049,401 (P&G CM4133FPQ), 62/049,397 (P&G CM4132FPQ), and
62/049,392 (P&G CM4131FPQ), all of which were filed on Sep. 12,
2014, and to U.S. Provisional Patent Application Ser. Nos.
62/210,005 (P&G 13971PQ), 62/210,014 (P&G 13972PQ),
62/210,020 (P&G 13973PQ), and 62/210,057 (P&G CM 4131P2Q),
all of which were filed on Aug. 26, 2015. The entire disclosures of
all of the above-referenced U.S. Provisional Patent Applications
are fully incorporated herein by reference.
FIELD OF THE INVENTION
[0002] An absorbent article comprising a topsheet/acquisition layer
laminate with an "airfelt-free" absorbent core is provided. Also,
an absorbent article comprising a topsheet/acquisition layer
laminate and an absorbent core comprising one or more optional
substantially absorbent material free area(s) is provided.
BACKGROUND OF THE INVENTION
[0003] An absorbent article typically comprises a topsheet, a
backsheet, and an absorbent core disposed between the topsheet and
the backsheet. Absorbent articles for personal hygiene, such as
disposable diapers for infants, training pants for toddlers or
adult incontinence undergarments are designed to absorb and contain
body exudates, in particular large quantity of urine. These
absorbent articles comprise several layers providing different
functions, for example a topsheet, a backsheet and in-between an
absorbent core, among other layers.
[0004] The function of the absorbent core is to absorb and retain
the exudates for a prolonged amount of time, for example overnight
for a diaper, minimize rewet to keep the wearer dry and avoid
soiling of clothes or bed sheets. The majority of currently
marketed absorbent articles comprise as absorbent material a blend
of comminuted wood pulp with superabsorbent polymers (SAP) in
particulate form, also called absorbent gelling materials (AGM),
see for example U.S. Pat. No. 5,151,092 (Buell). Absorbent articles
having a core consisting essentially of SAP as absorbent material
(so called "airfelt-free" absorbent cores) have also been proposed
but are less common than traditional mixed cores (see e.g.
WO2008/155699 (Hundorf), WO95/11652 (Tanzer), WO2012/052172 (Van
Malderen)).
[0005] The "airfelt-free" absorbent core provides less void area
than the absorbent core comprising a blend of comminuted wood pulp
with superabsorbent polymers (SAP) in particulate form. However,
the void volume is useful to aid in the retention of liquid and
provide storage space to acquire and absorb the liquid bodily
exudates.
[0006] There is therefore a need to develop an absorbent article
which provides void volume to acquire and absorb the liquid bodily
exudates.
[0007] There is also a need to develop an absorbent article
comprising an "airfelt-free" absorbent core which indicates that it
absorbs well.
SUMMARY OF THE INVENTION
[0008] An absorbent article for personal hygiene is provided and
comprises a longitudinal axis, a transversal axis perpendicular to
the longitudinal axis, a liquid permeable topsheet, an acquisition
layer, a liquid impermeable backsheet and an absorbent core. The
topsheet and the acquisition layer comprise fibers. The absorbent
core is located between the topsheet and the backsheet. The
absorbent core comprises an absorbent material. The absorbent
material comprises at least 80% of superabsorbent polymers, up to
substantially 100% of superabsorbent polymers, by total weight of
the absorbent material. A width of the acquisition layer in a
direction parallel to the transversal axis is less than a width of
the topsheet in a direction parallel to the transversal axis. The
absorbent article comprises a topsheet/acquisition layer laminate
comprising the liquid permeable topsheet and the acquisition layer
in a face to face relationship. The topsheet/acquisition layer
laminate comprises three-dimensional protrusions extending from a
plane of the topsheet/acquisition layer laminate. The topsheet and
acquisition layer are nested together such that a majority of the
three-dimensional protrusions formed in the topsheet coincide with
and fit together with a majority of the three-dimensional
protrusions formed in the acquisition layer.
[0009] The width of the acquisition layer of the
topsheet/acquisition layer laminate may not wider more than 40% of
the width of the distribution layer and/or more than 20% of the
width of the absorbent core in a direction parallel to the
transversal axis.
[0010] The absorbent article may comprise gasketing cuffs.
[0011] The majority of the three-dimensional protrusions of the
topsheet/acquisition layer laminate may at least or only be present
in the area where the topsheet overlaps the acquisition layer in
the topsheet/acquisition layer laminate.
[0012] The majority of the three-dimensional protrusions of the
topsheet/acquisition layer laminate may be present in the area
which extends parallel to the transversal axis of the absorbent
article. The majority of the three-dimensional protrusions of the
topsheet/acquisition layer laminate may be present in the area
which extends parallel to the longitudinal axis of the absorbent
article, but which does not extend beyond the area where gasketing
cuffs is attached to the absorbent article. In that case, the
majority of the three-dimensional protrusions which are formed in
the topsheet of the topsheet/acquisition layer laminate, are formed
from the fibers of the topsheet.
[0013] The absorbent article may be notionally divided into a front
region, a back region and a crotch region located between the front
and back region, wherein each of the front, back and crotch region
is 1/3 of the length of the absorbent article in a direction
parallel to the longitudinal axis, wherein the acquisition layer in
the topsheet/acquisition layer laminate is positioned in the front
region and at least partially in the crotch region.
[0014] Alternatively, the absorbent article may be notionally
divided into a front region, a back region and a crotch region
located between the front and back region, wherein each of the
front, back and crotch region is 1/3 of the length of the absorbent
article in a direction parallel to the longitudinal axis, wherein
the acquisition layer in the topsheet/acquisition layer laminate is
positioned in the back region and at least partially in the crotch
region.
[0015] The three-dimensional protrusions of the
topsheet/acquisition layer laminate may protrude towards the
backsheet or towards the body of the wearer when the absorbent
article is in use.
[0016] The majority of the three-dimensional protrusions may be
more than 50% or more than 60% or more than 70% or more than 80% or
more than 90% or more than 95% or more than 98% of the
three-dimensional protrusions in the topsheet/acquisition layer
laminate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] While the specification concludes with claims particularly
pointing out and distinctly claiming the present invention, it is
believed that the same will be better understood from the following
description read in conjunction with the accompanying drawings in
which:
[0018] FIG. 1 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate wherein
the length of the acquisition layer is less that the length of the
topsheet according to the present invention with some layers
partially removed;
[0019] FIG. 2 is a transversal cross-section of the diaper of FIG.
1;
[0020] FIG. 3 is a transversal cross-section of the diaper of FIG.
1;
[0021] FIG. 4 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate wherein
the three-dimensional protrusions of the topsheet/acquisition layer
laminate are only formed where the topsheet overlaps the
acquisition layer in the topsheet/acquisition layer laminate,
according to the present invention with some layers partially
removed;
[0022] FIG. 5 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with
another type of absorbent core according to the present invention
with some layers partially removed;
[0023] FIG. 6 is a transversal cross-section of a diaper of FIG.
5;
[0024] FIG. 7 is a transversal cross-section of the absorbent
article of FIG. 5 taken at the same point as FIG. 6 where channels
have formed as a result the absorbent article being loaded with
liquid bodily exudates;
[0025] FIG. 8 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with
the same type of absorbent core as in FIG. 5 but with one or more
substantially three-dimensional protrusion free area(s) of the
topsheet/acquisition layer laminate according to the present
invention with some layers partially removed;
[0026] FIG. 9 is a transversal cross-section of a diaper of FIG.
8;
[0027] FIG. 10 is a transversal cross-section of the absorbent
article of FIG. 8 taken at the same point as FIG. 9 where channels
have formed as a result the absorbent article being loaded with
liquid bodily exudates;
[0028] FIG. 11 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with a
carrier layer according to the present invention with some layers
partially removed;
[0029] FIG. 12A is a transversal cross-section of the diaper of
FIG. 11;
[0030] FIG. 12B is another transversal cross-section of the diaper
of FIG. 11;
[0031] FIG. 13 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with a
carrier layer according to the present invention with some layers
partially removed;
[0032] FIG. 14 is a transversal cross-section of the diaper of FIG.
13;
[0033] FIG. 15 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with an
acquisition layer positioned in a front region of the absorbent
article according to the present invention with some layers
partially removed;
[0034] FIG. 16 is an absorbent article in the form of a diaper
comprising an exemplary topsheet/acquisition layer laminate with an
acquisition layer positioned in a rear region of the absorbent
article according to the present invention with some layers
partially removed;
[0035] FIG. 17 is a perspective view of an apparatus comprising a
first and second intermeshing roll for forming the
topsheet/acquisition layer laminate of the present invention;
[0036] FIG. 18A is a cross-sectional depiction of a portion of the
apparatus shown in FIG. 17;
[0037] FIG. 18B is a perspective view of a portion of the second
intermeshing roll of the apparatus shown in FIG. 17;
[0038] FIG. 19A is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0039] FIG. 19B is a perspective view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate shown in FIG.
19A;
[0040] FIG. 19C is another perspective view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate shown in FIG.
19A;
[0041] FIG. 19D is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0042] FIG. 19E is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0043] FIG. 19F is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0044] FIG. 20A is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0045] FIG. 20B is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0046] FIG. 20C is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17;
[0047] FIG. 20D is a schematic view of a three-dimensional
protrusion of the topsheet/acquisition layer laminate obtained with
the apparatus shown in FIG. 17.
DETAILED DESCRIPTION OF THE INVENTION
Definition of Terms
[0048] The term "absorbent article" as used herein refers to
disposable products such as diapers, pants or feminine hygiene
sanitary napkins and the like which are placed against or in
proximity to the body of the wearer to absorb and contain the
various liquid bodily exudates discharged from the body. Typically
these absorbent articles comprise a topsheet, backsheet, an
absorbent core and optionally an acquisition layer and/or
distribution layer and other components, with the absorbent core
normally placed between the backsheet and the acquisition system or
topsheet. The absorbent article of the present invention may be a
diaper or pant.
[0049] The term "absorbent core" as used herein refers to a
component, which is placed or is intended to be placed within an
absorbent article and which comprises an absorbent material
enclosed in a core wrap. The term "absorbent core" does not cover
an acquisition or distribution layer or any other component of an
absorbent article which is not either an integral part of the core
wrap or placed within the core wrap. The absorbent core is
typically the component of an absorbent article which comprises
all, or at least the majority of, superabsorbent polymer and has
the most absorbent capacity of all the components of the absorbent
article.
[0050] The term "substantially free of absorbent material" or
"substantially absorbent material free" as used herein means that
the basis weight of the absorbent material is at least less than
10%, in particular less than 5% or 2%, of the average basis weight
of the absorbent material in the rest of the absorbent core.
[0051] The term "superabsorbent polymers" (herein abbreviated as
"SAP") as used herein refer to absorbent materials which are
cross-linked polymeric materials that can absorb at least 10 times
their weight of an aqueous 0.9% saline solution as measured using
the Centrifuge Retention Capacity (CRC) test (EDANA method WSP
241.2-05E). The SAP of the invention may in particular have a CRC
value of more than 20 g/g, or more than 25 g/g, or from 20 to 50
g/g, or from 20 to 40 g/g, or 25 to 35 g/g. The SAP useful in the
invention includes a variety of water-insoluble, but
water-swellable polymers capable of absorbing large quantities of
liquid bodily exudates.
[0052] The term "diaper" as used herein refers to an absorbent
article that is intended to be worn by a wearer about the lower
torso to absorb and contain liquid bodily exudates discharged from
the body. Diapers may be worn by infants (e.g. babies or toddlers)
or adults. They may be provided with fastening elements.
[0053] The term "pant" as used herein refers to an absorbent
article having fixed edges, a waist opening and leg openings
designed for infant or adult wearers. A pant is placed in position
on the wearer by inserting the wearer's legs into the leg openings
and sliding the pant-type absorbent article into position about the
wearer's lower torso. A pant may be preformed by any suitable
technique including, but not limited to, joining together portions
of the absorbent article using refastenable and/or non-refastenable
bonds (e.g., seam, weld, adhesive, cohesive bond, fastener, etc.).
A pant may be preformed anywhere along the circumference of the
article (e.g., side fastened, front waist fastened).
[0054] The term "extensible" as used herein refers to a material,
which, upon application of a force, is capable of undergoing an
apparent elongation of equal to or greater than at least 100% of
its original length along longitudinal and/or transversal axis of
the absorbent article at or before reaching the breaking force if
subjected to the following test:
[0055] The longitudinal and/or transversal axis tensile properties
are measured using a method using WSP 110.4 (05) Option, with a 50
mm sample width, 60 mm gauge length, and 60 mm/min rate of
extension.
[0056] It may be desirable that a material is capable of undergoing
an apparent elongation of equal to or greater than at least 100% or
110% or 120% or 130% up to 200% along longitudinal and/or
transversal axis of the absorbent article at or before reaching the
breaking force according to the Test Method as set out above.
[0057] If a material is capable of undergoing an apparent
elongation of less than 100% of its original length if subjected to
the above described test, it is "non-extensible" as used
herein.
[0058] The term "topsheet/acquisition layer laminate" as used
herein refers to an intimate combination of a topsheet with an
acquisition layer, both disposed in a face to face relationship.
The topsheet has a first and second surface. The first surface of
the topsheet is facing towards the body of the wearer when the
absorbent article is in use. The acquisition layer is facing the
backsheet or the optional distribution layer. A topsheet web and an
acquisition layer can have undergone a simultaneous and joint
mechanical deformation while the topsheet web and the acquisition
layer are combined with each other to form a topsheet/acquisition
layer laminate web which provides each topsheet/acquisition layer
laminate in each individual absorbent article. The
topsheet/acquisition layer laminate comprises deformations forming
three-dimensional protrusions. The topsheet/acquisition layer
laminate is formed by nesting together the topsheet and acquisition
layer such that a majority of the three-dimensional protrusions
formed in the topsheet coincide with and fit together with a
majority of the three-dimensional protrusions formed in the
acquisition layer, as shown in FIGS. 19A, 19B, 19C and 20A.
[0059] In the topsheet/acquisition layer laminate, the topsheet and
acquisition layer may be in an intimate contact with each
other.
[0060] There is no interpenetration of one of the topsheet or the
acquisition layer into and through the respective other topsheet or
the acquisition layer in the area of the three-dimensional
protrusions of the topsheet/acquisition layer laminate. The
topsheet and the acquisition layer are thus extensible such that
the topsheet and/or acquisition layer cannot rupture and
interpenetrate into and through a ruptured topsheet or the
acquisition layer.
[0061] In the area of the three-dimensional protrusions, the
topsheet and/or acquisition layer may comprise one or more
interruptions. The formation of the one or more interruptions may
be due to the properties of the topsheet and acquisition layer,
i.e. apparent elongation of the fibers, fiber mobility, ability to
deform and stretch in the area where the three-dimensional
protrusions of the topsheet/acquisition layer laminate are formed.
In other words, the topsheet may be less extensible than the
acquisition layer or vice versa, however, the non-ruptured topsheet
or acquisition layer does not interpenetrate the respective
ruptured topsheet or acquisition layer.
[0062] Hence, the topsheet/acquisition layer laminate may be formed
by interrupting one of the topsheet or acquisition layer in the
area of the three-dimensional protrusions of the
topsheet/acquisition layer laminate such that the three-dimensional
protrusions of the respective other non-interrupted topsheet or
acquisition layer at least partially fit together with the
three-dimensional protrusions of the interrupted topsheet or
acquisition layer, as shown in FIGS. 19D, 19E, 20B and 20C.
[0063] Alternatively or in addition to what has been set out above,
the topsheet/acquisition layer laminate may be formed by
interrupting the topsheet and acquisition layer in the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate and the three-dimensional protrusions of the topsheet
coincide with and fit together with the three-dimensional
protrusions of the acquisition layer. The interruptions in the
topsheet in the area of the three-dimensional protrusions of the
topsheet/acquisition layer laminate may not coincide with the
interruptions in the acquisition layer in the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate, as shown in FIGS. 19F and 20D.
[0064] The terms "interruptions", as used herein, refer to holes
formed in the topsheet and/or acquisition layer during the
formation of the topsheet/acquisition layer laminate, and does not
include the pores and interstices between fibers typically present
in nonwovens.
[0065] The term "mechanically deforming and combining" as used
herein means that the topsheet web and acquisition layer are put in
a face to face relationship and can be simultaneously mechanically
deformed between a first and second roll and intimately combined at
the same time. The mechanical deformation of the topsheet web and
the acquisition layer depends on the process, the required
apparatus but also on the properties of the topsheet and the
acquisition layer, i.e. apparent elongation of the fibers, fiber
mobility, ability to deform and stretch in the area where the
three-dimensional protrusions of the topsheet/acquisition layer
laminate are formed, ability to undergo plastic deformation which
sets after existing the first and second roll, or springing
partially back due to elastic recovery.
[0066] The mechanical deformation may comprise intermeshing the
topsheet together with the acquisition layer between a first and
second intermeshing roll. The first intermeshing roll comprises a
plurality of ridges and corresponding grooves. The second
intermeshing roll comprises a plurality of rows of
circumferentially-spaced teeth and corresponding grooves such that
a plurality of deformations comprising three-dimensional
protrusions is obtained. A tunnel-shaped loop may be one type of
three-dimensional protrusion.
[0067] For each three-dimensional protrusion: [0068] The topsheet
is nested into the acquisition layer or vice versa such that the
majority of the three-dimensional protrusions of the topsheet and
of the acquisition layer coincide with and fit together, as shown
in FIGS. 19A, 19B, 19C and 20A. There is no interpenetration of one
of the topsheet or acquisition layer into or through the respective
other topsheet or acquisition layer in the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate. [0069] In addition to what has been set out above, one of
the topsheet or acquisition layer may be interrupted in the area of
the three-dimensional protrusions of the topsheet/acquisition layer
laminate such that the three-dimensional protrusions made of the
respective other non-interrupted topsheet or acquisition layer at
least partially fit together with the three-dimensional protrusions
of the interrupted topsheet or of the interrupted acquisition
layer, as shown in FIGS. 19D, 19E, 20B and 20C. [0070]
Alternatively or in addition to what has been set out above, the
topsheet and acquisition layer may be interrupted in the area of
the three-dimensional protrusions of the topsheet/acquisition layer
laminate and the three-dimensional protrusions of the topsheet
coincide with and fit together with the three-dimensional
protrusions of the acquisition layer. The interruptions in the
topsheet in the area of the three-dimensional protrusions of the
topsheet/acquisition layer laminate may not coincide with the
interruptions in the acquisition layer in the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate, as shown in FIGS. 19F and 20D.
[0071] The term "a majority of the three-dimensional protrusions"
as used herein means that more than 50% or more than 60% or more
than 70% or more than 80% or more than 90% or more than 95% or more
than 98% of the three-dimensional protrusions in the
topsheet/acquisition layer laminate web or in the
topsheet/acquisition layer laminate of the absorbent article, each
comprises a base forming an opening and having a protrusion base
width, an opposed distal portion and the one or more side wall
between the base and the distal portion of the three-dimensional
protrusion. The base, distal portion and one or more side wall are
formed by fibers such that the three-dimensional protrusion has
only an opening at the base (as exemplary shown in a FIG. 19A).
[0072] The term "tunnel-shaped loop" as used herein means that a
three-dimensional protrusion of the topsheet/acquisition layer
laminate is defined by a plurality of loops extending from the
topsheet to the acquisition layer or from the acquisition layer to
the topsheet. The plurality of loops comprises one or more fibers
made of the topsheet/acquisition layer laminate. The fibers of the
plurality of loops are generally aligned with one another such that
the plurality of loops form a tunnel-shaped loop. A tunnel-shaped
loop may be defined as a cylindania, i.e. a cylinder cut in half
along its length, comprising openings at each extremity of the
tunnel-shaped loop and a base opening.
[0073] The term "cellulosic fiber" as used herein refers to natural
fibers which typically are wood pulp fibers. Applicable wood pulps
include chemical pulps, such as Kraft, sulfite, and sulfate pulps,
as well as mechanical pulps including, for example, groundwood,
thermomechanical pulp and chemically modified thermomechanical
pulp. Pulps derived from both deciduous trees (hereinafter, also
referred to as "hardwood") and coniferous trees (hereinafter, also
referred to as "softwood") may be utilized. The hardwood and
softwood fibers can be blended, or alternatively, can be deposited
in layers to provide a stratified web.
[0074] The term "dry-laid fiber" as used herein means fibers which
have been provided in a fluid medium which is gaseous (air).
[0075] The term "wet-laid fiber" as used herein comprises
cellulosic fibers which have been suspended in an aqueous medium,
such as water, before being converted into a web and dried
according to a wet-laid papermaking process.
[0076] The term "web" as used herein means a material capable of
being wound into a roll. Webs may be nonwovens.
[0077] The term "nonwoven web" as used herein refers to a
manufactured material, web, sheet or batt of directionally or
randomly oriented fibers, bonded by friction, and/or cohesion
and/or adhesion, excluding paper and products which are woven,
knitted, tufted, stitch-bonded, incorporating binding yarns or
filaments, or felted by wet milling, whether or not additionally
needled. The fibers may be of natural or man-made origin. The
fibers may be staple or continuous filaments or be formed in situ.
The porous, fibrous structure of a nonwoven may be configured to be
liquid permeable or impermeable, as desired.
[0078] The term "area substantially free of three-dimensional
protrusion" or "substantially three-dimensional protrusion free
area" as used herein means that the area comprises less than 10%,
in particular less than 5%, or less than 2% of the whole surface of
the area of three-dimensional protrusions or no three-dimensional
protrusions at all.
[0079] The substantially three-dimensional protrusion free area(s)
may have a length L' projected on the longitudinal axis of the
absorbent article that is at least 10% of the length L of the
article. The substantially three-dimensional protrusion free
area(s) may have a width W' along at least part of its length or
along the complete length L' which is at least 2 mm, or at least 3
mm or at least 4 mm, at least 8 mm, at least 10 mm, up to for
example 20 mm, or 16 mm or 12 mm. The width of the substantially
three-dimensional protrusion free area(s) may be constant through
substantially the whole length of the three-dimensional protrusion
free area(s) or may vary along its length.
[0080] The term "joined to" as used herein encompasses
configurations in which an element is directly secured to another
element by affixing the element directly to the other element; and
configurations in which the element is indirectly secured to the
other element by affixing the element to intermediate member(s)
which in turn are affixed to the other element. The term "joined
to" encompasses configurations in which an element is secured to
another element at selected locations, as well as configurations in
which an element is completely secured to another element across
the entire surface of one of the elements. The term "joined to"
includes any known manner in which elements can be secured
including, but not limited to mechanical entanglement.
[0081] The term "joined adjacent to the transversal edges" as used
herein means that when a first and/or second transversal edge of a
first layer is/are joined adjacent to a first and/or second
transversal edges of a second layer, the first and/or second
transversal edge of the first layer are disposed within an area
spaced inboard from the first and/or second transversal edge of the
second layer. The area has a width which is from 1 to 30% of the
width of the second layer.
[0082] "Comprise," "comprising," and "comprises" are open ended
terms, each specifies the presence of the feature that follows,
e.g. a component, but does not preclude the presence of other
features, e.g. elements, steps, components known in the art or
disclosed herein. These terms based on the verb "comprise" should
be read as encompassing the narrower terms "consisting essential
of" which excludes any element, step or ingredient not mentioned
which materially affect the way the feature performs its function,
and the term "consisting of" which excludes any element, step, or
ingredient not specified. Any preferred or exemplary embodiments
described below are not limiting the scope of the claims, unless
specifically indicated to do so. The words "typically", "normally",
"advantageously" and the likes also qualify features which are not
intended to limit the scope of the claims unless specifically
indicated to do so.
[0083] The airfelt-free absorbent core provides less void area than
the absorbent core comprising a blend of comminuted wood pulp with
superabsorbent polymers (SAP) in particulate form. However, the
void volume is useful to aid in the retention of liquid and provide
storage space to acquire and absorb the liquid bodily exudates.
[0084] Known three-dimensional topsheets could be used to provide
additional void volume to the absorbent article. Known
three-dimensional topsheets are often obtained with increased basis
weight and fluffiness of the topsheet. However, such relatively
high basis weight and fluffiness (i.e. relatively high void volume)
for three-dimensional topsheets might lead to increased wetness of
the three-dimensional topsheets as more liquid remains in the
topsheet. Especially, the three-dimensional topsheet includes small
pores which can be more difficult to be dewatered through a
secondary topsheet or an acquisition layer.
[0085] One solution could be the elimination of any secondary
topsheet or acquisition layer in order to put the three-dimensional
topsheet in direct contact with the absorbent core. However, this
may lead to an increase of the acquisition time and consequently an
increased risk of leakage. This risk may be tempered by adding a
relatively high amount of superabsorbent material in the
"airfelt-free" absorbent core. The solution of adding a relatively
high amount of absorbent material in the "airfelt-free" absorbent
core, however, negatively impacts the cost of the absorbent article
and also leads to an increase in overall absorbent article
caliper.
[0086] It has been found that bringing the topsheet and acquisition
layer in a face to face relationship and having the
topsheet/acquisition layer laminate comprising three-dimensional
protrusions extending from a plane of the topsheet/acquisition
layer laminate can help providing additional void volume without
impacting the dryness at the skin facing layer of the absorbent
article. The topsheet and acquisition layer are nested together
such that a majority of the three-dimensional protrusions formed in
the topsheet coincide with and fit together with a majority of the
three-dimensional protrusions formed in the acquisition layer.
General Description of the Absorbent Article 20
[0087] An exemplary absorbent article 20 in which the absorbent
core 28 of the invention can be used is a taped diaper 20 as
represented in FIG. 1; FIG. 4 and FIG. 5 with a different absorbent
core construction. FIG. 1; FIG. 4 and FIG. 5 are top plan views of
the exemplary diaper 20, in a flat-out state, with portions of the
structure being cut-away to more clearly show the construction of
the diaper 20. This diaper 20 is shown for illustration purpose
only as the invention may be used for making a wide variety of
diapers or other absorbent articles.
[0088] The absorbent article 20 comprises a topsheet/acquisition
layer laminate 245 formed from a liquid permeable topsheet 24 and
an acquisition layer 52. In other words, the absorbent article 20
comprises a liquid permeable topsheet 24 and an acquisition layer
52 characterized in that the topsheet 24 and the acquisition layer
52 are joined to form a topsheet/acquisition layer laminate 245.
The absorbent article 20 comprises a liquid impermeable backsheet
25 and an absorbent core 28 between the topsheet 24 and the
backsheet 25. The absorbent article 20 comprises a front edge 10, a
back edge 12, and two longitudinal side edges 13. The front edge 10
is the edge of the absorbent article 20 which is intended to be
placed towards the front of the user when worn, and the back edge
12 is the opposite edge. The absorbent article 20 may be notionally
divided by a longitudinal axis 80 extending from the front edge 10
to the back edge 12 of the absorbent article 20 and dividing the
absorbent article 20 in two substantially symmetrical halves
relative to this axis, when viewing the absorbent article 20 from
the wearer facing side in a flat out configuration, as exemplarily
shown in FIG. 1, FIG. 4 and FIG. 5.
[0089] The absorbent article 20 may comprise a distribution layer
54 which may comprise a dry-laid fibrous structure or a wet-laid
fibrous structure. The topsheet/acquisition layer laminate 245 is
facing towards the body of the wearer when the absorbent article 20
is in use.
[0090] The wet-laid fibrous structure comprising wet-laid fibers
may have a Wet burst Strength from 50 to 500 g according to the Wet
Burst Strength Test Method and combinations thereof.
[0091] The distribution layer 54 may comprise a dry-laid fibrous
structure. The dry-laid fibrous structure may comprise dry-laid
fibers 540. The dry-laid fibrous structure may comprise a mixture
including superabsorbent polymers and dry-laid fibers 450. The
dry-laid fibers may comprise intra-fiber cross-linked cellulosic
fibers.
[0092] The distribution layer 54 may have an average basis weight
of from 30 to 400 gsm, in particular from 100 to 300 gsm or from 50
to 250 gsm.
[0093] As explained more in a process detailed below, a topsheet 24
and an acquisition layer 52 can be simultaneously mechanically
deformed and combined together to form a topsheet/acquisition layer
laminate 245. The mechanical deformations provide a
three-dimensional structure to the topsheet/acquisition layer
laminate 245. The topsheet 24 and the acquisition layer 52 are
nested together such that a majority of the three-dimensional
protrusions formed in the topsheet 24 coincide with and fit
together with a majority of the three-dimensional protrusions
formed in the acquisition layer 52.
[0094] The topsheet 24 and acquisition layer 52 may be in an
intimate contact with each other.
[0095] The absorbent article 20 may comprise elasticized gasketing
cuffs 32 present between the topsheet 24 and the backsheet 25 and
upstanding barrier leg cuffs 34. FIGS. 1, 4 and 5 also show other
typical diaper components such as a fastening system comprising
fastening tabs 42 attached towards the back edge 12 of the
absorbent article 20 and cooperating with a landing zone 44 towards
the front edge 10 of the absorbent article 20. The absorbent
article 20 may also comprise other typical components, which are
not represented in the Figures, such as a back elastic waist
feature, a front elastic waist feature, transverse barrier cuff(s),
a lotion application, etc.
[0096] As shown in FIG. 7, the barrier leg cuffs 34 may be
delimited by a proximal edge 64 joined to the rest of the article
20, typically the topsheet 24 and/or the backsheet 25, and a free
terminal edge intended to contact and form a seal with the wearer's
skin. The barrier leg cuffs 34 may be joined at the proximal edge
64 by a bond 65 which may be made for example by adhesive bonding,
fusion bonding or combination of known bonding means. Each barrier
leg cuff 34 may comprise one, two or more elastic strings 35 to
provide a better seal. The gasketing cuffs 32 may be placed
laterally outwardly relative to the barrier leg cuffs 34. The
gasketing cuffs 32 can provide a better seal around the thighs of
the wearer. Usually each gasketing leg cuff 32 will comprise one or
more elastic string or elastic element 33 for example between the
topsheet 24 and the backsheet 25 in the area of leg openings.
[0097] The absorbent article 20 can also be notionally divided by a
transversal axis 90 in a front region and a back region of equal
length measured on the longitudinal axis, when the absorbent
article 20 is in a flat state. The absorbent article's transversal
axis 90 is perpendicular to the longitudinal axis 80 and placed at
half the length of the absorbent article 20. The length of the
absorbent article 20 can be measured along the longitudinal axis 80
from the front edge 10 to the back edge 12 of the absorbent article
20. The topsheet 24, acquisition layer 52, distribution layer 54
and absorbent core 28 each have a width which can be measured from
their respective transversal edges and in parallel to the
transversal axis 90.
[0098] The absorbent article 20 is notionally divided in a front
region 36, a back region 38 and a crotch region 37 located between
the front and the back region of the absorbent article 20. Each of
the front, back and crotch region is 1/3 of the length of the
absorbent article 20. The absorbent article may also comprise front
ears 46 and back ears 40 as it is known in the art.
[0099] The absorbent core 28 of the present invention may comprise
as absorbent material 60 a blend of cellulosic fibers (so called
"airfelt") and superabsorbent polymers in particulate form
encapsulated in one or more substrates, see for example U.S. Pat.
No. 5,151,092 (Buell). Alternatively, the absorbent core 28 may be
airfelt free as described in detail below.
[0100] Generally, the absorbent cores 28 useful in the present
invention (see below) can be defined by the periphery of the layer
formed by the absorbent material 60 within the core wrap 160, as
seen from the top side of the absorbent core 28. The absorbent core
28 can take various shapes, in particular display a so-called "dog
bone" or "hour-glass" shape, which shows a tapering along its width
towards the middle or "crotch" region of the core. In this way, the
absorbent core 28 may have a relatively narrow width in an area of
the absorbent core 28 intended to be placed in the crotch region of
the absorbent article. This may provide for example better wearing
comfort. The absorbent core 28 may thus have a width (as measured
in the transversal direction) at its narrowest point which is less
than about 100 mm, 90 mm, 80 mm, 70 mm, 60 mm or even less than
about 50 mm. The absorbent core 28 can also be generally
rectangular, see for example as shown in FIG. 5, but other
deposition areas can also be used such as a "T" or "Y" or
"hour-glass" or "dog-bone" shape (See for example FIG. 4).
[0101] Some components of the absorbent article 20 will now be
discussed in more details.
"Airfelt-Free" Absorbent Core 28
[0102] The absorbent core 28 of the invention may comprise an
absorbent material 60 enclosed within a core wrap 160. The
absorbent material 60 may comprise from 80% to 100% of SAP, such as
SAP particles, by total weight of the absorbent material 60. The
core wrap 160 is not considered as an absorbent material 60 for the
purpose of assessing the percentage of SAP in the absorbent core
28.
[0103] By "absorbent material" it is meant a material which has at
least some absorbency and/or liquid retaining properties, such as
SAP, cellulosic fibers as well as some hydrophilically treated
synthetic fibers. Typically, adhesives used in making absorbent
cores have no absorbency properties and are not considered as
absorbent material. The SAP content may be substantially higher
than 80%, for example at least 85%, at least 90%, at least 95% and
even up to and including 100% of the weight of the absorbent
material 60 contained within the core wrap 160. This above SAP
content substantially higher than 80% SAP may provide a relatively
thin absorbent core 28 compared to conventional absorbent cores
typically comprising between 40-60% SAP and 40-60% of cellulosic
fibers. The absorbent material 60 of the invention may in
particular comprise less than 10% weight percent, or less than 5%
weight percent, or even be substantially free of natural and/or
synthetic fibers. The absorbent material 60 may advantageously
comprise little or no cellulosic fibers, in particular the
absorbent core 28 may comprise less than 15%, 10%, or 5% (airfelt)
cellulosic fibers by weight of the absorbent core 28, or even be
substantially free of cellulose fibers. Such absorbent core 28 may
be relatively thin and thinner than conventional airfelt cores.
FIG. 1, FIG. 2 and FIG. 3 are illustrations of an absorbent article
20 comprising an "airfelt-free" absorbent core 28.
[0104] "Airfelt-free" absorbent cores 28 comprising relatively high
amount of SAP with various absorbent core designs have been
proposed in the past, see for example in U.S. Pat. No. 5,599,335
(Goldman), EP1447066A1 (Busam), WO95/11652 (Tanzer),
US2008/0312622A1 (Hundorf), and WO2012/052172 (Van Malderen).
[0105] The absorbent core 28 of the invention may comprise adhesive
for example to help immobilizing the SAP within the core wrap 160
and/or to ensure integrity of the core wrap 160 in particular when
the core wrap 160 is made of one or more substrates. The core wrap
160 will typically extend over a larger area than strictly needed
for containing the absorbent material 60 within.
Core Wrap
[0106] The absorbent material 60 is encapsulated in one or more
substrates.
[0107] The core wrap 160 comprises a top side 16 facing the
topsheet 24 and a bottom side 16' facing the backsheet 25. The core
wrap 160 may be made of a single substrate folded around the
absorbent material 60. The core wrap 160 may be made of two
substrates (one mainly providing the top side 16 and the other
mainly providing the bottom side 16') which are attached to
another, as exemplarily shown in FIG. 2. Typical configurations are
the so-called C-wrap and/or sandwich wrap. In a C-wrap, as
exemplarily shown in FIG. 6, the longitudinal and/or transversal
edges of one of the substrate are folded over the other substrate
to form flaps. These flaps are then bonded to the external surface
of the other substrate, typically by bonding with an adhesive. The
so called C-wrap construction can provide benefits such as improved
resistance to bursting in a wet loaded state compared to a sandwich
seal.
[0108] The core wrap 160 may be formed by any materials suitable
for receiving and containing the absorbent material 60. The core
wrap 160 may in particular be formed by a nonwoven web, such as a
carded nonwoven, spunbond nonwoven ("S") or meltblown nonwoven
("M"), and laminates of any of these. For example spunmelt
polypropylene nonwovens are suitable, in particular those having a
laminate web SMS, or SMMS, or SSMMS, structure, and having a basis
weight range of about 5 gsm to 15 gsm. Suitable materials are for
example disclosed in U.S. Pat. No. 7,744,576, US2011/0268932A1,
US2011/0319848A1 or US2011/0250413A1. Nonwoven materials provided
from synthetic fibers may be used, such as polyethylene (PE),
polyethylene terephthalate (PET) and in particular polypropylene
(PP).
"Airfelt-Free" Absorbent Core 28 Comprising Substantially Absorbent
Material Free Areas 26
[0109] The absorbent core 28 may comprise an absorbent material
deposition area 8 defined by the periphery of the layer formed by
the absorbent material 60 within the core wrap 160.
[0110] The absorbent core 28 may comprise one or more substantially
absorbent material free area(s) 26 which is/are substantially free
of absorbent material 60 and through which a portion of the top
side 16 of the core wrap 160 is attached by one or more core wrap
bond(s) 27 to a portion of the bottom side 16' of the core wrap
160, as shown in FIGS. 5 and 6. In particular, there can be no
absorbent material 60 in these areas. Minimal amount such as
contaminations with absorbent material 60 that may occur during the
making process are not considered as absorbent material 60. The one
or more substantially absorbent material free area(s) 26 may be
advantageously confined by the absorbent material 60, which means
that the substantially absorbent material free area(s) 26 do(es)
not extend to any of the edge of the absorbent material deposition
area 8.
[0111] If the substantially absorbent material free area 26 extends
to any of the edges of the absorbent material deposition area 8,
each substantially absorbent material free area 26 may have areas
of absorbent material 60 on either side of each substantially
absorbent material free area 26.
[0112] The absorbent core 28 may comprise at least two
substantially absorbent material free areas 26 symmetrically
disposed on both sides of the longitudinal axis of the absorbent
core 28, as shown in FIG. 5.
[0113] The substantially absorbent material free area(s) 26 may be
straight and completely oriented longitudinally and parallel to the
longitudinal axis but also may be curved or have one or more curved
portions.
[0114] Furthermore, in order to reduce the risk of liquid bodily
exudate leakages, the substantially absorbent material free area(s)
26 advantageously do not extend up to any of the edges of the
absorbent material deposition area 8, and are therefore surrounded
by and fully encompassed within the absorbent material deposition
area 8 of the absorbent core 28. Typically, the smallest distance
between a substantially absorbent material free area 26 and the
closest edge of the absorbent material deposition area 8 is at
least 5 mm.
[0115] "Airfelt free" absorbent cores 28 comprising substantially
absorbent material free areas 26 have been proposed, see for
example in EP Patent Application No. 12196341.7.
[0116] One or more channel(s) 26' along the substantially absorbent
material free area(s) 26 in the absorbent core 28 may start forming
when the absorbent material 60 absorbs a liquid and starts
swelling. As the absorbent core 28 absorbs more liquid, the
depressions within the absorbent core 28 formed by the channel(s)
26' will become deeper and more apparent to the eye and the touch.
The formation of the channel(s) 26' may also serve to indicate that
the absorbent article 20 has been loaded with liquid bodily
exudates. The core wrap bond(s) 27 should remain substantially
intact at least during a first phase as the absorbent material 60
absorbs a moderate quantity of liquid bodily exudates.
[0117] As shown in FIG. 7, when the absorbent material swells, the
core wrap bonds 27 remain at least initially attached in the
substantially absorbent material free areas 26. The absorbent
material 60 swells in the rest of the absorbent core 28 when it
absorbs a liquid, so that the core wrap 160 thus forms channels 26'
along the substantially absorbent material free areas 26 comprising
the core wrap bonds 27.
General Structure and Properties of the Topsheet/Acquisition Layer
Laminate
[0118] A topsheet/acquisition layer laminate 245 having a
three-dimensional structure is provided.
[0119] The absorbent article 20 comprises a longitudinal axis 80, a
transversal axis 90 perpendicular to the longitudinal axis 90, a
liquid permeable topsheet 24 having a first and second surface and
an acquisition layer 52 having a first and second surface. The
first surface of the topsheet will be facing towards the body of
the wearer when the absorbent article 20 is in use.
[0120] The topsheet 24 and acquisition layer 52 are aligned in a
face to face relationship such that the second surface of the
topsheet 24 is in contact with the first surface of the acquisition
layer 52. The topsheet 24 and the acquisition layer 52 comprise
fibers.
[0121] The absorbent article 20 comprises a topsheet/acquisition
layer laminate 245 which comprises the topsheet 24 and the
acquisition layer 52 in a face to face relationship. The topsheet
24 and acquisition layer 52 are nested together such that a
majority of the three-dimensional protrusions formed in the
topsheet 24 coincide with and fit together with a majority of the
three-dimensional protrusions formed in the acquisition layer 52 to
provide a topsheet/acquisition layer laminate 245 having
three-dimensional protrusions 250.
[0122] The majority of the three-dimensional protrusions 250 may be
more than 50% or more than 60% or more than 70% or more than 80% or
more than 90% or more than 95% or more than 98% of the
three-dimensional protrusions 250 in the topsheet/acquisition layer
laminate 245.
[0123] According to the process detailed below, the topsheet 24 and
the acquisition layer 52 can be simultaneously mechanically
deformed and combined together in a face to face relationship to
provide a topsheet/acquisition layer laminate 245. This means that
both topsheet 24 and acquisition layer 52 can be mechanically
deformed and combined together at the same time. The
topsheet/acquisition layer laminate 245 has a first surface
comprising the second surface of the acquisition layer 52.
[0124] The absorbent article 20 may comprise a dry-laid fibrous
structure or a wet-laid fibrous structure. The distribution layer
54 may free of tow fibers.
[0125] The distribution layer 54 may for example comprise at least
50% by weight of cross-linked cellulose fibers. The cross-linked
cellulosic fibers may be crimped, twisted, or curled, or a
combination thereof including crimped, twisted, and curled. This
type of material has been used in the past in disposable diapers as
part of an acquisition system, for example US 2008/0312622 A1
(Hundorf).
[0126] Exemplary chemically cross-linked cellulosic fibers suitable
for a distribution layer 54 are disclosed in U.S. Pat. No.
5,549,791, U.S. Pat. No. 5,137,537, WO9534329 or US2007/118087.
Exemplary cross-linking agents may include polycarboxylic acids
such as citric acid and/or polyacrylic acids such as acrylic acid
and maleic acid copolymers.
[0127] The distribution layer may typically have an average basis
weight of from 30 to 400 g/m.sup.2, in particular from 100 to 300
g/m.sup.2. The density of the distribution layer may vary depending
on the compression of the article, but may be of between 0.03 to
0.15 g/cm.sup.3, in particular 0.08 to 0.10 g/cm.sup.3 measured at
0.30 psi (2.07 kPa).
[0128] The dry-laid fibrous structure may comprise a mixture
including superabsorbent polymers (SAP) and dry-laid fibers 540.
The dry-laid fibers 540 may comprise intra-fiber cross-linked
cellulosic fibers.
[0129] The absorbent article 20 may comprise gasketing cuffs 32.
The majority of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 may at least be present in
the area where the topsheet 24 overlaps the acquisition layer 52 in
the topsheet/acquisition layer laminate 245. However, the majority
of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 may be present in the
topsheet 24 and the acquisition layer 52 in the area which extends
parallel to the transversal axis 90 of the absorbent article 20.
The majority of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 may be present in the area
which extends parallel to the longitudinal axis 80 of the absorbent
article 20, but which does not extend beyond the area where
gasketing cuffs 32 is attached to the absorbent article 20, in
particular to the topsheet 24, as shown in FIG. 2 or 3. In that
case, the majority of the three-dimensional protrusions 250 which
are formed in the topsheet 24 of the topsheet/acquisition layer
laminate 245, are formed from the fibers of the topsheet 24.
[0130] Alternatively, the majority of the three-dimensional
protrusions 250 of the topsheet/acquisition layer laminate 245 may
be present in the area which extends parallel to the transversal
axis 90 of the absorbent article 20 such that the area comprising
the three-dimensional protrusions of the topsheet 24 overlaps the
acquisition layer 52. The length of the area of the
three-dimensional protrusions of the topsheet/acquisition layer
laminate 245 may be from 5% to 60% or from 10% to 40% wider than
the length of the acquisition layer 52 of the topsheet/acquisition
layer laminate 245. The majority of the three-dimensional
protrusions 250 of the topsheet/acquisition layer laminate 245 may
extend in the area which extends parallel to the longitudinal axis
80 of the absorbent article 20 such that the area comprising the
majority of the three-dimensional protrusions of the topsheet 24
overlaps the acquisition layer 52. The width of the area of the
majority of the three-dimensional protrusions of the
topsheet/acquisition layer laminate 245 may be from 5% to 60% or
from 10% to 40% wider than the width of the acquisition layer 52 of
the topsheet/acquisition layer laminate 245. In that case, the
majority of the three-dimensional protrusions 250 which are formed
in the topsheet 24 of the topsheet/acquisition layer laminate 245,
are formed from the fibers of the topsheet 24.
[0131] In still another alternative, the majority of the
three-dimensional protrusions 250 of the topsheet/acquisition layer
laminate 245 may only be present where the topsheet 24 overlaps the
acquisition layer 52 in the topsheet/acquisition layer laminate
245, as shown in FIG. 4.
[0132] Hence, the majority of the three-dimensional protrusions 250
can provide an impression of depth and can support the caregiver's
perception that the absorbent article 20 is well able to absorb the
liquid bodily exudates.
[0133] The majority of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 can have a measured
protrusion height from 0.3 mm to 5 mm or from 0.5 mm to 3 mm or
from 1.0 mm to 2.0 mm according to the Protrusion Height Test
Method as described below.
[0134] The majority of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 can have a measured
protrusion base width of the three-dimensional protrusions 250 from
0.3 mm to 10 mm or from 0.5 mm to 5 mm or from 0.5 mm to 3.0 mm or
from 1.0 mm to 2.5 mm or from 1.5 mm to 2.5 mm according to the
Protrusion Base Width Test Method as described below.
[0135] The majority of the three-dimensional protrusions 250 having
a shape with a specific height and width can provide an impression
of depth and can support the caregiver's perception that the
absorbent article 20 is well able to absorb the liquid bodily
exudates.
[0136] The absorbent article 20 comprises an absorbent core 28
which comprises an absorbent material 60. The absorbent material 60
may comprise from 80% to 100% of SAP, such as SAP particles, by
total weight of the absorbent material 60.
[0137] Another type of absorbent material may be water-absorbing
foams based on cross-linked monomers comprising acid groups, see
for example from EP 0 858 478 B1, WO 97/31971 A1, WO 99/44648 A1
and WO 00/52087 A1.
[0138] These three-dimensional protrusions 250 provide void volume
to receive the liquid bodily exudates. At the same time, the
topsheet 24 and acquisition layer 52 in the topsheet/acquisition
layer laminate 245 may be in intimate contact because the topsheet
24 and acquisition layer 52 are nested together. Also, the
topsheet/acquisition layer laminate 245 is in close contact with
the underlaying layer, i.e. the distribution layer 54. Hence, the
liquid bodily exudates are transmitted more efficiently from the
topsheet/acquisition layer laminate 245 to the distribution layer
54, which maintains or even improves the dryness of the topsheet 24
of the topsheet/acquisition layer laminate 245. Rewet remains the
same or is even reduced at the skin of the wearer. The
topsheet/acquisition layer laminate 245 may also enable more
efficient use of an "airfelt-free" absorbent core 28. Overall, the
topsheet 24 of the topsheet/acquisition layer laminate 245 has a
similar or even an improved dryness than a three-dimensional
topsheet 24 placed on top of an acquisition layer 52. Hence, the
absorbent article 20 comprising an "airfelt-free" absorbent core
and further comprising the topsheet/acquisition layer laminate 245
as described above can help assisting in the retention of liquid
and providing storage space to acquire and absorb the liquid bodily
exudates.
[0139] The majority of the three-dimensional protrusions 250 may
comprise void areas 253 which do not contact the skin of the
wearer. The absorbent article 20 may be in less contact with the
skin of the wearer in comparison with a flat topsheet. The void
areas 253 of the topshseet/acquisitions layer laminate 245 can help
the air to permeate between the skin of the wearer and the
topsheet/acquisition layer laminate 245. Hence, the void areas 253
of the topshseet/acquisitions layer laminate 245 can improve the
breathability of the topsheet/acquisition layer laminate 245.
[0140] In addition to improve dryness, the void areas 253 of the
topshseet/acquisitions layer laminate 245 can also allow feces to
be absorbed and acquired within them. In that case, the present
invention is suitable to absorb feces of relatively low
viscosity.
[0141] A width of the acquisition layer 52 in a direction parallel
to the transversal axis 90 is less than a width of the topsheet 24
in a direction parallel to the transversal axis 90. If the width of
both topsheet 24 and acquisition layer 52 were the same, wicking of
the liquid bodily exudates underneath the gasketing cuffs 32 might
occur. Hence, the liquid bodily exudates might not be properly
absorbed by the absorbent core 28, which may lead to leakage of the
liquid bodily exudates out of the absorbent article 20. If the
width of the acquisition layer 52 in a direction parallel to the
transversal axis 90 is less that the width of the topsheet 24 in a
direction parallel to the transversal axis 90, the acquisition
layer 52 which may receive the liquid bodily exudates from the
topsheet 24 can directly transmit the liquid bodily exudates to the
distribution layer 54 in order to be subsequently absorb by the
absorbent core 28. Hence, the liquid bodily exudates temporary
stored in the acquisition layer 52 of the topsheet/acquisition
layer laminate 245 will not readily be drawn towards and underneath
the gasketing cuffs 32 by capillary forces. Leakage can thus be
reduced by having the width of the acquisition layer 52 less that
the width of the topsheet 24 in the topsheet/acquisition layer
laminate 245 in a direction parallel to the transversal axis
90.
[0142] In order to help reducing leakage and rewet, the width of
the acquisition layer 52 of the topsheet/acquisition layer laminate
245 in a direction parallel to the transversal axis 90 may not be
more than 40% wider than the width of the distribution layer 54
and/or more than 20% wider than the width of the absorbent core 28
in a direction parallel to the transversal axis 90. In that case,
the liquid bodily exudates may not accumulate at or adjacent to the
transversal edges of the acquisition layer. Wicking of the liquid
bodily exudates underneath the gasketing cuffs 32 is prevented.
Indeed, when the acquisition layer 52 of the tospheet/acquisition
layer laminate 245 is no more than 20% wider than the width of the
absorbent core 28, the liquid bodily exudates can readily be
transported into the absorbent core 28, which can efficiently drain
the fluid from the acquisition layer 52 into the absorbent core 28.
Wicking of the liquid bodily exudates form the acquisition layer 52
underneath the gasketing cuffs 32 is prevented.
[0143] The acquisition layer 52 can receive the liquid bodily
exudates that pass through the topsheet 24 and can distribute them
to underlying absorbent layers. In such a case, the topsheet 24 in
the topsheet/acquisition layer laminate 245 may be less hydrophilic
than the acquisition layer 52. The topsheet 24 of the
topsheet/acquisition layer laminate 245 can be readily
dewatered.
[0144] In order to enhance dewatering of the topsheet 24 of the
topsheet/acquisition layer laminate 245, the pore size of the
acquisition layer 52 may be reduced. For this, the acquisition
layer 52 may made of fibers with relatively small denier. The
acquisition layer 52 may also have an increased density.
Channels and Opening of the Channels
[0145] As set out above, as shown in FIG. 7, when the absorbent
material swells, the core wrap bonds 27 remain at least initially
attached in the substantially absorbent material free areas 26.
Channels 26' are formed along the substantially absorbent material
free areas 26 comprising the core wrap bonds 27.
[0146] In a second phase the core wrap bond(s) 27 in the channel(s)
26' can start opening to provide more space for the absorbent
material 60 to swell while keeping most of the benefits of the
channel(s) 26' such as increased flexibility of the absorbent core
28 in transversal direction and liquid bodily exudate
management.
[0147] The strength of the core wrap bond(s) 27 in the channel(s)
26' may be lower than the strength of the bonds to attach a single
substrate together or two or more substrates together to form the
core wrap. Hence, the channel(s) 26' open without any tearing of
the core wrap when the absorbent material 60 swells.
[0148] The strength of the core wrap bond 27 within the channel 26'
can be controlled for example by varying the amount and nature of
the adhesive used for the attaching the two sides of the core wrap,
the pressure used to make the core wrap bond and/or the
distribution of the absorbent material 60, as more absorbent
material 60 will usually causes more swelling and will put more
pressure on the bond. The extensibility of the material of the core
wrap may also play a role.
[0149] In a third phase, corresponding to a very high saturation of
the absorbent core 28, the core wrap bond(s) 27 in the channel(s)
26' can open further, optionally completely, to provide even more
space for the swelling absorbent material 60 to expand. Therefore,
the absorbent article 20 is fully loaded, i.e. the absorbent
article 20 has reached its full capacity.
[0150] The consumer can notice that when the absorbent core 28
swells, channels 26' are formed. From the backsheet 25 of the
absorbent article 20, the consumer can readily see the
morphological change of the absorbent article 20 when swelling.
[0151] However, it will be desirable to provide another signal for
the consumer that the absorbent article 20 comprising an
"airfelt-free" absorbent core can absorb well when he looks at the
absorbent article 20 from the topsheet 24.
[0152] The topsheet/acquisition layer laminate 245 comprising
three-dimensional protrusions 250 can already provide an impression
of depth and can support the caregiver's perception that the
absorbent article 20 is well able to absorb the liquid bodily
exudates.
[0153] In order to reinforce this impression of depth, the
topsheet/acquisition layer laminate may comprise one or more
substantially three-dimensional protrusion free area(s) 246.
[0154] The substantially three-dimensional protrusion free area 246
may comprise less than 10%, in particular less than 5%, or less
than 2% of the whole surface of the three-dimensional protrusion
free area.
[0155] If the substantially three-dimensional protrusion free area
246 extends to any of the edges of the topsheet/acquisition layer
laminate 245, each substantially three-dimensional protrusion free
area 246 may have areas of three-dimensional protrusions 250 on
either side of each substantially three-dimensional protrusion free
area 246.
[0156] The portions of the topsheet 24 and the acquisition layer 52
of the topsheet/acquisition layer laminate 245 may be attached
together continuously along the substantially three-dimensional
protrusion free area(s) 246. However, one or more bonds along the
substantially three-dimensional protrusion free area(s) 246 may
also be discontinuous (intermittent) such as series of point bonds.
The bond(s) may be provided by known attachment means, such as
adhesive bonding, pressure bonding, ultrasonic bonding or heat
bonding, dynamic mechanical bonding or combination thereof.
[0157] The attachment of the portions of the topsheet 24 and the
acquisition layer 52 of the topsheet/acquisition layer laminate 245
may be provided by one or more adhesive material(s).
[0158] For example, the attachment of the portions of the topsheet
24 and the acquisition layer 52 of the topsheet/acquisition layer
laminate 245 may include a uniform continuous layer of adhesive, a
patterned layer of adhesive, or an array of separate lines,
spirals, or spots of adhesive. Suitable attachment means comprise
an open pattern network of filaments of adhesive as disclosed in
U.S. Pat. No. 4,573,986. Other suitable attachment means include
several lines of adhesive filaments which are swirled into a spiral
pattern, as is illustrated by the apparatus and methods shown in
U.S. Pat. No. 3,911,173, U.S. Pat. No. 4,785,996; and U.S. Pat. No.
4,842,666. Adhesives which have been found to be satisfactory are
manufactured by H. B. Fuller Company of St. Paul, Minn. and
marketed as HL-1620 and HL 1358-XZP.
[0159] The substantially three-dimensional protrusion free area(s)
may have a length L' projected on the longitudinal axis of the
absorbent article that is at least 10% of the length L of the
article. The substantially three-dimensional protrusion free
area(s) may have a width W' along at least part of its length or
along the complete length L' which is at least 2 mm, or at least 3
mm or at least 4 mm, at least 8 mm, at least 10 mm, up to for
example 20 mm, or 16 mm or 12 mm. The width of the substantially
three-dimensional protrusion free area(s) may be constant through
substantially the whole length of the three-dimensional protrusion
free area(s) or may vary along its length.
[0160] Advantageously, the portion of the topsheet 24 and the
portion of the acquisition layer 52 of the topsheet/acquisition
layer laminate 245 may be attached together at one or more
substantially three-dimensional protrusion free area(s) 246 by an
adhesive comprising a plurality of adhesive lines which are
substantially parallel to the longitudinal axis 80 of the absorbent
article 20. The plurality of adhesive lines may be provided by an
adhesive slot apparatus. The plurality of adhesive lines may
represent the one or more bond(s).
[0161] The following examples of the shape and size of the
substantially three-dimensional protrusion free area 246 are not
limiting. The substantially three-dimensional protrusion free area
246 may be present within the crotch region 37 of the absorbent
article 20. In particular, the substantially three-dimensional
protrusion free area 246 may be extending longitudinally parallel
to the longitudinal axis 80 of the absorbent article 20 and/or
transversely parallel to the transversal axis 90 of the absorbent
article 20. FIG. 8 shows two longitudinally extending substantially
three-dimensional protrusion free area 246 as an example. The
topsheet/acquisition layer laminate 245 may also comprise more than
two substantially three-dimensional protrusion free areas 246 for
example at least 3, or at least 4 or at least 5 or at least 6.
[0162] The topsheet/acquisition layer laminate 245 may comprise at
least 2 substantially three-dimensional protrusion free area 246
symmetrically disposed on both sides of the longitudinal axis 80 of
the absorbent article 20. Shorter substantially three-dimensional
protrusion free area(s) 246 may also be present, for example in the
back region or the front region 38, 36 of the absorbent article
20.
[0163] The substantially three-dimensional protrusion free area(s)
246 may be at least partially oriented in the longitudinal
direction of the absorbent article 20. This means typically that
each substantially three-dimensional protrusion free area 246
extends more in the longitudinal direction than in the transverse
direction, and typically at least twice as much in the longitudinal
direction than in the transverse direction.
[0164] The substantially three-dimensional protrusion free area(s)
246 may be straight and completely oriented longitudinally and
parallel to the longitudinal axis 80 but also may be curved or have
one or more curved portions. In particular some or all these
substantially three-dimensional protrusion free area(s) 246, in
particular these substantially three-dimensional protrusion free
area(s) 246 present in the crotch region 37, may be concave towards
the longitudinal axis 80, as for example represented in FIG. 8 for
the pair of substantially three-dimensional protrusion free areas
246. The radius of curvature may typically be at least equal (and
preferably at least 1.5 or at least 2.0 times this average
transverse dimension) to the average transverse dimension of the
absorbent article 20; and also straight but with an angle of (e.g.
from) 5.degree. up to 30.degree., or for example up to 20.degree.,
or up to 10.degree. with a line parallel to the longitudinal axis
80. The radius of curvature may be constant for each substantially
three-dimensional protrusion free area 246, or may vary along its
length. This may also include substantially three-dimensional
protrusion free area(s) 246 with an angle therein, provided said
angle between two parts of an area 246 is at least 120.degree.,
preferably at least 150.degree.. These substantially
three-dimensional protrusion free area(s) 246 may also be branched,
for example a central substantially three-dimensional protrusion
free area superposed with the longitudinal axis 80 in the crotch
region 37 which branches towards the back and/or towards the front
of the absorbent article 20.
[0165] There may be no substantially three-dimensional protrusion
free area 246 that coincides with the longitudinal axis 80 of the
absorbent article 20. When present as one of symmetrical pair(s)
relative to the longitudinal axis 80 of the absorbent article 20,
substantially three-dimensional protrusion free area(s) 246 may be
spaced apart from one another over their whole longitudinal
dimensions. Generally, the smallest spacing distance may be for
example at least 5 mm, or at least 10 mm, or at least 16 mm.
[0166] Furthermore, in order to reduce the risk of liquid bodily
exudate leakages, substantially three-dimensional protrusion free
area(s) 246 advantageously do not extend up to any of the edges of
the topsheet/acquisition layer laminate 245, and in particular
beyond the area where gasketing cuffs 32 is attached to the
absorbent article 20. Typically, the smallest distance between a
substantially three-dimensional protrusion free area 246 and the
closest edge of the topsheet/acquisition layer laminate 245 is at
least 5 mm.
[0167] At least some one or more substantially three-dimensional
protrusion free area(s) 246 of the topsheet/acquisition layer
laminate 245 may coincide with the one or more substantially
absorbent material free area(s) 26 of the absorbent core 28.
[0168] When the substantially three-dimensional protrusion free
area(s) 246 of the topsheet/acquisition layer laminate 245 coincide
with the one or more substantially absorbent material free area(s)
26 of the absorbent core 28, the impression of depth is reinforced.
The caregiver can perceive that the absorbent article 20 is well
able to absorb the liquid bodily exudates.
Carrier Layer
[0169] A carrier layer 17 may be disposed between the
topsheet/acquisition layer laminate 245 and the dry-laid fibrous
structure, as shown in FIG. 11, 12A. According to the method used
for making the three-dimensional structure of the
topsheet/acquisition layer laminate 245, when the topsheet 24 and
acquisition layer 52 are mechanically deformed together, holes
might unintentionally occur. When the distribution layer 54
comprises a dry-laid fibrous structure, the dry-laid fibers 540 of
the dry-laid fibrous structure may pass through the unintentional
holes formed at the topsheet/acquisition layer laminate 245 and
contact undesirably the skin of the wearer. The carrier layer 17
may act as a barrier layer to impede the dry-laid fibers 540 of the
dry-laid fibrous structure from passing through the holes of the
topsheet/acquisition layer laminate 245 unintentionally formed by
the three-dimensional mechanical deformation of the topsheet 24
with the acquisition layer 52, as shown in FIGS. 11 and 12A. Also,
the carrier layer 17 may help the transfer of the liquid bodily
exudates from the topsheet/acquisition layer laminate 245 to the
dry-laid fibrous structure.
[0170] The carrier layer 17 may comprise a first and second surface
(171, 172). The second surface 172 of the carrier layer 17 may be
facing the topsheet/acquisition layer laminate 245. The first
surface 171 of the carrier layer 17 may be attached at or adjacent
to its longitudinal edges to the absorbent core 28. Hence, when the
carrier layer 17 is disposed between the topsheet/acquisition layer
laminate 245 and the dry-laid fibrous structure, and the carrier
layer 17 is attached to the absorbent core 28, the dry-laid fibers
540 of the dry-laid fibrous structure may be not able to escape
between the carrier layer 17 and the absorbent core 28, as
exemplified in FIG. 12B. The attachment of the carrier layer 17 to
the longitudinal edges of the absorbent core 28 may include a
uniform continuous layer of adhesive 173, a discontinuous patterned
application of adhesive or an array of separate lines, spirals, or
spots of adhesive.
[0171] Alternatively, the carrier layer 17 may be disposed between
the dry-laid fibrous structure and the absorbent core 28, as shown
in FIG. 13. Hence, the carrier layer may help to distribute and
transfer of the liquid bodily exudates from the distribution layer
54 to the absorbent core 28, as shown in FIGS. 13 and 14, which
enables more efficient use of the absorbent core 28.
[0172] The carrier layer 17 may be attached at or adjacent to its
longitudinal edges to the first surface of the topsheet/acquisition
layer laminate 245. Hence, when the carrier layer 17 is disposed
between the dry-laid fibrous structure and the absorbent core 28,
and the carrier layer 17 is attached to the first surface of the
topsheet/acquisition layer laminate 245, the dry-laid fibers 540 of
the dry-laid fibrous structure may be not able to escape between
the topsheet/acquisition layer laminate 245 and the carrier layer
17. The attachment of the carrier layer 17 to the longitudinal
edges to the first surface of the topsheet/acquisition layer
laminate 245 may include a uniform continuous layer of adhesive, a
discontinuous patterned application of adhesive or an array of
separate lines, spirals, or spots of adhesive.
[0173] A length of the acquisition layer 52 of the
topsheet/acquisition layer laminate 245 in a direction parallel to
the longitudinal axis 80 may be less than a length of the topsheet
24 in a direction parallel to the longitudinal axis 80, as shown in
FIG. 4. When the length of the acquisition layer 52 of the
topsheet/acquisition layer laminate 245 in a direction parallel to
the longitudinal axis 80 is less than the length of the topsheet 24
in a direction parallel to the longitudinal axis 80, the liquid
bodily exudates cannot be readily drawn towards the longitudinal
edges (10, 12) of the absorbent article 20, which reduces
leakage.
[0174] The length of the acquisition layer 52 in the
topsheet/acquisition layer laminate 245 may be less than the length
of the absorbent core 28 in a direction parallel to the
longitudinal axis 80, see for example FIG. 4.
[0175] The acquisition layer 52 of the topsheet/acquisition layer
laminate 245 may be positioned in the front region 36 and at least
partially in the crotch region 37 of the absorbent article 20, as
shown in FIG. 15. In that case, positioning the acquisition layer
52 of the topsheet/acquisition layer laminate 245 in the front
region 36 of the absorbent article 20 helps for acquiring and
distributing the liquid bodily exudates such as urine, around the
pee point of the wearer.
[0176] The acquisition layer 52 of the topsheet/acquisition layer
laminate 245 may be positioned in the back region 38 and at least
partially in the crotch region 37 of the absorbent article 20, as
shown in FIG. 16. Positioning the acquisition layer 52 of the
topsheet/acquisition layer laminate 245 in the back region 38 of
the absorbent article 20 helps at acquiring the feces of the
wearer, especially when the feces have a low viscosity.
[0177] The majority of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 may protrude towards the
backsheet 25 or towards the body of the wearer when the absorbent
article is in use.
[0178] The majority of the three-dimensional protrusions 250 may
form, in conjunction, one or more graphics such as a logo, e.g. the
Pampers Heart logo. Having graphics can support the caregiver's
perception that the absorbent article is well able to absorb the
liquid bodily exudates.
[0179] The topsheet/acquisition layer laminate 245 may be
notionally divided into a first and second area. The first area may
comprise three-dimensional protrusions 250 which protrude towards
the backsheet 25. The second area may comprise three-dimensional
protrusions 250 which protrude towards the body of the wearer when
the absorbent article is in use.
[0180] For instance, the first area may be located in the front
region 36 and at least partially in the crotch region 37 of the
absorbent article 20 and the second regions may be located in the
back region 38 and at least partially in the crotch region 37 of
the absorbent article 20.
[0181] Having the first area where the three-dimensional
protrusions 250 of the topsheet/acquisition layer laminate 245
protrude towards the backsheet 25 can help acquiring and absorbing
the liquid bodily exudates to the absorbent core 28. Having the
second area where the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 protrude towards the body
of the wearer when the absorbent article is in use can improve
cleaning the body from the exudates. Hence, a combination of the
first and second area can allow the absorbent article 20 to better
perform.
[0182] The topsheet 24 of the topsheet/acquisition layer laminate
245 may be coated with a lotion composition. The lotion composition
may be located in the areas of the topsheet 24 which are between
the three-dimensional protrusions 250 of the topsheet/acquisition
layer laminate 245.
[0183] Typical lotion compositions used in diapers are disclosed in
U.S. Pat. No. 6,426,444 B2. The resulting lotion composition may be
applied to the topsheet/acquisition layer laminate by spraying,
printing (e.g., flexographic printing), coating (e.g., contact slot
coating, gravure coating), extrusion, microencapsulation or
combinations of these application techniques.
[0184] The majority of the three-dimensional protrusions 250 may be
disposed in any suitable arrangement across the plane of the
topsheet/acquisition layer laminate 245. Suitable arrangements
include, but are not limited to: staggered arrangements, and zones.
In some cases, the topsheet/acquisition layer laminate 245 may
comprise both three-dimensional protrusions 250 and other features
known in the art such as embossments and apertures. The
three-dimensional protrusions 250 and other features may be in
separate zones, be intermixed, or overlap. Intermixed arrangements
can be created in any suitable manner. In some cases, intermixed
arrangements can be created by using the techniques described in
U.S. Patent Publication No. US 2012/0064298 A1, Orr, et al. In
other cases, overlapping arrangements can be created by forming the
three-dimensional protrusions 250 and then subsequently passing the
topsheet/acquisition layer laminate 245 between a forming member
having male forming elements thereon and a compliant surface, and
applying pressure to the web with the forming member and compliant
surface. These techniques for producing overlapping arrangements
enable three-dimensional protrusions 250 and other features to be
combined so they are disposed in different locations on the
topsheet/acquisition layer laminate 245 or they can cause at least
some of the three-dimensional protrusions 250 and at least some of
the other features (apertures, embossments) to be disposed in the
same location on the topsheet/acquisition layer laminate 245.
The Mechanical Deformations and the Resulted Three-Dimensional
Protrusions
[0185] The topsheet/acquisition layer laminate 245 may be
obtainable by the process comprising the following steps of
providing a first and second intermeshing roll (211, 212) as shown
in FIGS. 17, 18A and 18B.
[0186] The first intermeshing roll 211 of an apparatus 200 may
comprise a plurality of ridges 215 and corresponding grooves 216
which extend unbroken substantially about a circumference of the
first intermeshing roll 211.
[0187] The second intermeshing roll 212 may comprise a plurality of
rows of circumferentially-extending ridges that have been modified
to be rows of circumferentially-spaced teeth 217 and corresponding
grooves 218, wherein the plurality of rows of
circumferentially-spaced teeth 217 extend in spaced relationship
about at least a portion of the second intermeshing roll 212.
[0188] The topsheet 24 and acquisition layer 52 may be intermeshed
together between the first and second intermeshing rolls (211, 212)
such that the ridges 215 of the first intermeshing roll 211 extend
into the grooves 218 of the second intermeshing roll 212 and the
teeth 217 of the second intermeshing roll 212 extend into the
grooves 216 of the first intermeshing roll 211 to form the
topsheet/acquisition layer laminate 245. Hence, a plurality of
deformations comprising three-dimensional protrusions 250 is
obtained.
[0189] The three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 may be only formed where
the topsheet 24 overlaps the acquisition layer 52 in the
topsheet/acquisition layer laminate 245.
[0190] The first and second intermeshing roll (211, 212) may be
further defined by a tooth height TH, a pitch P and a depth of
engagement E as shown in FIG. 18A. The tooth height TH may be
measured from a surface of the second intermeshing roll 212 to a
tip of a tooth 217. The tooth height TH may range from 0.5 mm to 10
mm or from 0.5 mm to 5 mm.
[0191] The pitch P may be defined as a tooth-to-tooth spacing which
is measured from a tip of a first tooth to a tip of a second tooth
of the second intermeshing roll 212. The first and second tooth of
the second intermeshing roll 212 may be located in the
cross-machine direction. The pitch P may range from 1 mm to 10 mm
or from 1 mm to 5 mm.
[0192] The depth of engagement E is a measure of how much the first
and second intermeshing rolls (211, 212) are engaging with each
other. The depth of engagement E may be measured from a tip of a
ridge 215 to a tip of a tooth 217 which is located next to the
ridge 215 in the cross-machine direction. The depth of engagement E
may range from 0.5 mm to 10 mm or from 0.5 mm to 5 mm or from 1 to
4 mm.
[0193] Each tooth 217 of the second intermeshing roll 212 may be
defined by a circumferential tooth length TL and a tooth distance
TD, as shown in FIGS. 17 and 18B. The circumferential tooth length
TL may be measured from a leading edge to a trailing edge at a
tooth tip. The tooth length TL may range from 0.5 mm to 10 mm or
from 0.5 mm to 4 mm or from 1 mm to 4 mm.
[0194] Each tooth is separated from one another circumferentially
by the tooth distance TD. The tooth distance TD may be measured
from a leading edge of a first tooth to a trailing edge of a second
tooth. The first and second teeth of the second intermeshing roll
212 may be on the same circumference in the machine direction. The
tooth distance TD may range from 0.5 mm to 10 mm or from 0.5 mm to
5 mm or from 1 mm to 3 mm.
[0195] Other orientations of the teeth 217, grooves (216, 218) and
ridges 215 may be possible, e.g. in CD direction versus MD
direction. The topsheet 24 and acquisition layer laminate are
nested together such that three-dimensional protrusions formed in
the topsheet coincide with and fit together with three-dimensional
protrusions formed in the acquisition layer.
[0196] The topsheet 24 and acquisition layer 52 may be both
extensible. The topsheet 24 and/or acquisition layer 52 may be able
to stretch and do not interpenetrate through the respective
ruptured topsheet or acquisition layer.
[0197] Generally, the extensibility of the materials composing the
topsheet 24 and acquisition layer 52 can be selected according to
the desired sizes of the three-dimensional protrusions 250. If
relatively large three-dimensional protrusions 250 are desired,
materials with a relatively higher extensibility will be
chosen.
[0198] For instance, the topsheet 24 or acquisition layer 52 may be
capable of undergoing an apparent elongation of equal to or greater
than at least 100% or 110% or 120% or 130% up to 200% along the
longitudinal and/or transversal axis of the absorbent article at or
before reaching the breaking force according to the Test Method as
set out in the Definition part.
[0199] In some cases, it might be desired to have three-dimensional
protrusions 250 which are larger either along the longitudinal or
transversal axis of the absorbent article 20. For this, the
materials composing the topsheet 24 and acquisition layer 52 can be
thus more extensible in either the longitudinal axis 80 versus the
transversal axis 90 of the absorbent article 20 or vice versa.
[0200] The topsheet/acquisition layer laminate 245 may comprise a
majority of three-dimensional protrusions 250. The majority of the
three-dimensional protrusions 250 may protrude towards the
distribution layer 54 (see also FIG. 2) or towards the carrier
layer 17 (see FIGS. 11, 12A). When the three-dimensional
protrusions 250 extend towards the distribution layer 54, the area
of contact between the acquisition layer 52 of the
topsheet/acquisition layer laminate 245 and the underneath
distribution layer 54 is improved. Hence, the transfer of the
liquid bodily exudates from the topsheet/acquisition layer laminate
245 to the distribution layer 54 can be increased.
[0201] FIG. 19A-FIG. 19F shows different alternatives of
three-dimensional protrusions 250. A loop-shaped protrusion may be
one type of three-dimensional protrusions 250, see for example FIG.
19B. A loop-shaped protrusion may be obtained by the intermeshing
process step as just described above using the apparatus 200.
[0202] Another type of three-dimensional protrusion 250 may be a
tunnel-shaped loop. Generally, a tunnel-shape loop may comprise a
base forming an opening and also an opening at a leading edge 261
and an opening at a trailing edge 262, see for example FIG.
19C.
[0203] As shown in FIGS. 19A and 19B, a three-dimensional
protrusion 250 in the form of a loop-shaped protrusion may comprise
an inner and outer three-dimensional protrusion 251A and 251B. The
inner three-dimensional protrusion 251A of the topsheet 24 is
nested in the outer three-dimensional protrusion 251B of the
acquisition layer 52.
[0204] The three-dimensional protrusions 250 may be made from
intermeshing the topsheet 24 with the acquisition layer 52 such
that the inner three-dimensional protrusions 251A of the topsheet
24 and the outer three-dimensional protrusions 251B of the
acquisition layer 52 coincide with and fit together.
[0205] The inner three-dimensional protrusion 251A may comprise a
plurality of looped fibers 254A of the topsheet 24. The outer
three-dimensional protrusion 251B in which the inner
three-dimensional protrusion 251A is nested, may comprise a
plurality of looped fibers 254B of the acquisition layer 52.
[0206] The three-dimensional protrusion 250 may comprise a void
area 253 which is the portion of the three-dimensional protrusion
251A which does not comprise any fibers. The three-dimensional
protrusion 250 may be defined by a base 256 forming an opening
proximate to the topsheet 24, a distal portion 257 and one or more
side walls 255 between the base 256 and the distal portion 257. The
three-dimensional protrusion 250 may be defined by a protrusion
base width WL.sub.1 of the base 256 forming an opening which is
measured from two opposite side walls of the inner
three-dimensional protrusion 251A at the base 256. Each
three-dimensional protrusion 250 may be defined by a width WL.sub.2
of the void area 253 which is the maximal width measured between
two opposite side walls of the inner three-dimensional protrusion
251A. The width WL.sub.2 of the void area 253 may be greater than
the protrusion base width WL.sub.1 of the base 256 of the
three-dimensional protrusion 250. Measurements of the dimensions of
the protrusion base width WL.sub.1 of the base 256 and the width
WL.sub.2 of the distal portion 257 can be made on a
photomicrograph. When the size of the protrusion base width
WL.sub.1 of the base 256 is specified herein, it will be
appreciated that if the openings are not of uniform width in a
particular direction, the protrusion base width, WL.sub.1, is
measured at the widest portion. The three-dimensional protrusion
250 may have only one opening at the base 256. The
three-dimensional protrusions 250 may be formed from the fibers of
the topsheet 24 and the acquisition layer 52. The three-dimensional
protrusions 250 may comprise a base 256 forming an opening, an
opposed distal portion 257, and one or more side walls 255 between
the bases 256 and the distal portions 257 of the three-dimensional
protrusions 250. The base 256, distal portion 257 and the one or
more side walls 255 may be formed by fibers such that the
three-dimensional protrusion has only an opening at the base 256.
At least 50% or at least 80% of the three-dimensional protrusions
250 of the topsheet/acquisition layer laminate 245 may only have
openings at the base 256. The three-dimensional protrusion 250 may
have a conical shape, see for example FIG. 19B.
[0207] As shown in FIG. 19C, each inner and outer three-dimensional
protrusion (251A, 251B) may be made of a plurality of looped fibers
(254A, 254B) which are aligned with one another in a machine
direction and cross direction to create a tunnel-shaped loop 250
having openings (261, 262) on each extremity of the tunnel in
addition to the opening at the base 256. In that case, the
protrusion base width WL1 of the base 256 is relatively small. The
protrusion base width WL.sub.1 of the base 256 of the
three-dimensional protrusion 250 may range from 0.1 mm to 1.2 mm or
from 0.1 mm to 1 mm or from 0.1 mm to 0.5 mm.
[0208] In the area of the three-dimensional protrusions, the
topsheet 24 and/or acquisition layer 52 may comprise one or more
interruptions. The formation of the one or more interruptions may
be due to the properties of the topsheet 24 and acquisition layer
52. The topsheet 24 may less extensible with regard to fiber
mobility and/or fiber extensibility than the acquisition layer 52
or vice versa such that a hole starts to form in the topsheet 24
and/or acquisition layer 52.
[0209] Hence, as shown in FIG. 19D or 19E, the acquisition layer 52
may be interrupted in the area of the three-dimensional protrusion
250 of the topsheet/acquisition layer laminate 245. The
three-dimensional protrusion 251B of the interrupted acquisition
layer 52 may comprise an interruption 258.
[0210] Generally, the acquisition layer 52 may have a lower
extensibility than the topsheet 24. In such cases, the acquisition
layer 52 may start to rupture and form an interruption, i.e. the
fibers composing the acquisition layer 52 may be less extensible
and/or mobile than the fibers composing the topsheet 24.
[0211] The three-dimensional protrusion 251A of the non-interrupted
topsheet 24 may coincide with and fit together with the
three-dimensional protrusion 251B of the interrupted acquisition
layer, as shown in FIG. 19D. In other words, the topsheet 24 is not
pushed through the acquisition layer 52 such that the topsheet 24
does not interpenetrate through the acquisition layer 52.
[0212] Alternatively, the three-dimensional protrusion 251A of the
non-interrupted topsheet 24 may partially fit together with the
three-dimensional protrusion 251B of the interrupted acquisition
layer, as shown in FIG. 19E.
[0213] Likewise, the topsheet 24 may be interrupted in the area of
the three-dimensional protrusion 250 of the topsheet/acquisition
layer laminate 245.
[0214] Generally, the topsheet 24 may have a lower extensibility
than the acquisition layer 52. In such cases, the topsheet 24 may
start to rupture and form an interruption, i.e. the fibers
composing the topsheet 24 may be less extensible and/or mobile than
the fibers composing the acquisition layer 52.
[0215] In another alternative, the topsheet 24 and acquisition
layer 52 may be interrupted in the area of the three-dimensional
protrusions 250 of the topsheet/acquisition layer laminate 245 and
the three-dimensional protrusions of the topsheet 251A coincide
with and fit together with the three-dimensional protrusions 251B
of the acquisition layer. The interruptions (258A) in the topsheet
24 in the area of the three-dimensional protrusions 250 of the
topsheet/acquisition layer laminate 245 will not coincide with the
interruptions (258B) in the acquisition layer 52 in the area of the
three-dimensional protrusions 250 of the topsheet/acquisition layer
laminate 245, as shown in FIG. 19F.
[0216] The plurality of three-dimensional protrusions 250 may
protrude towards the body of the wearer when the absorbent article
20 is in use (see also FIG. 3). When the three-dimensional
protrusions 250 protrude towards the body of the wearer when the
absorbent article 20 is in use, the area of contact between the
topsheet 24 of the topsheet/acquisition layer laminate 245 and the
wearer's skin is enhanced. Hence, the topsheet/acquisition layer
laminate 245 provides cushioning to the wearer and an improved
sensation of comfort.
[0217] FIG. 20A-FIG. 20D shows alternatives how a plurality of
three-dimensional protrusions 250, e.g. loop-shaped protrusions,
may protrude from the acquisition layer 52 to the topsheet 24 of
the topsheet/acquisition layer laminate 245. In those alternatives,
a three-dimensional protrusion 250 in the form of a loop-shaped
protrusion may comprise an inner and outer three-dimensional
protrusion 251A and 251B. The inner three-dimensional protrusion
251A of the acquisition layer 52 is nested in the outer
three-dimensional protrusion 251B of the topsheet 24. The inner
three-dimensional protrusion 251A may comprise a plurality of
looped fibers 254B of the acquisition layer 52. The outer
three-dimensional protrusion 251B in which the inner
three-dimensional protrusion 251A is nested, may comprise a
plurality of looped fibers 254A of the topsheet 24.
[0218] An area of 10 cm.sup.2 of the topsheet/acquisition layer
laminate 245 may comprise from 5 to 100 three-dimensional
protrusions 250 from 10 to 50 three-dimensional protrusions 250 or
from 20 to 40 three-dimensional protrusions 250.
Precursor Materials for the Topsheet and the Acquisition Layer
[0219] The topsheet/acquisition layer laminate 245 of the present
invention can be made of any suitable nonwoven materials
("precursor materials"). In some cases, the topsheet/acquisition
layer laminate 245 may also be free of cellulose materials. The
precursor materials for the topsheet/acquisition layer laminate 245
may have suitable properties in order to be deformed. The suitable
properties of the precursor materials may include: apparent
elongation of the fibers, fiber mobility, ability to deform and
stretch in the area where the three-dimensional protrusions 250 of
the topsheet/acquisition layer laminate 245 are formed. Hence, the
precursor materials are capable of undergoing mechanical
deformation to ensure that the three-dimensional protrusion 250
will not tend to recover or return to the prior configuration of a
flat topsheet 24 laminated on a flat acquisition layer 52.
[0220] Several examples of nonwoven materials suitable for use as a
topsheet 24 for the topsheet/acquisition layer laminate 245 may
include, but are not limited to: spunbonded nonwovens; carded
nonwovens; and nonwovens with relatively specific properties to be
able to be readily deformed.
[0221] One suitable nonwoven material as a topsheet 24 for the
topsheet/acquisition layer laminate 245 may be an extensible
polypropylene/polyethylene spunbonded nonwoven. One suitable
nonwoven material as a topsheet 24 for the topsheet/acquisition
layer laminate 245 may be a spunbonded nonwoven comprising
polypropylene and polyethylene. The fibers may comprise a blend of
polypropylene and polyethylene. Alternatively, the fibers may
comprise bi-component fibers, such as a sheath-core fiber with
polyethylene on the sheath and polypropylene in the core of the
fiber.
[0222] The topsheet 24 of the topsheet/acquisition layer laminate
245 may have a basis weight from 8 to 40 gsm or from 8 to 30 gsm or
from 8 to 20 gsm.
[0223] Suitable nonwoven materials for the acquisition layer 52 of
the topsheet/acquisition layer laminate 245 may include, but are
not limited to: spunbonded nonwovens, through-air bonded ("TAB")
carded high loft nonwoven materials, spunlace nonwovens,
hydroentangled nonwovens, and resin bonded carded nonwoven
materials.
[0224] Spunbonded PET may be denser than carded nonwovens,
providing more uniformity and opacity. Since PET fibers are not
very extensible, the nonwoven can be bonded such that at least some
of the fibers can be separated easily from the bond sites to allow
the fibers to pull out of the bond sites and rearrange when the
material is strained. This type of bonding, e.g. pressure bonding
can help increasing the level of mobility of the fibers. Indeed,
the fibers tend to pull out from the bond sites under tension.
[0225] The acquisition layer exhibits a basis weight from 10 to 120
gsm or from 10 to 100 gsm or from 10 to 80 gsm.
[0226] The topsheet 24 and/or acquisition layer 52 may have a
density from 0.01 to 0.4 g/cm.sup.3 or from 0.01 to 0.25 g/cm.sup.3
or from 0.04 to 0.15 g/cm.sup.3.
[0227] The topsheet 24 and acquisition layer 52 may be joined
together prior or during the mechanical deformation. If desired an
adhesive, chemical bonding, resin or powder bonding, or thermal
bonding between the topsheet 24 and acquisition layer 52 may be
selectively utilized to bond certain regions or all of the topsheet
24 and acquisition layer 52 together. In addition, the topsheet 24
and acquisition layer 52 may be bonded during processing, for
example, by carding the topsheet 24 of onto the acquisition layer
52 and thermal point bonding the combined layers.
[0228] Prior to any mechanical deformation, the topsheet 24 may be
attached to the acquisition layer 52. For instance, the topsheet 24
may be attached to acquisition layer 52 where the topsheet 24 and
acquisition layer 52 overlaps. The attachment of the topsheet 24 to
the acquisition layer 52 may include a uniform continuous layer of
adhesive, a discontinuous patterned application of adhesive or an
array of separate lines, spirals, or spots of adhesive. The basis
weight of the adhesive in the topsheet/acquisition layer laminate
245 may be from 0.5 to 30 gsm or from 1 to 10 gsm or from 2 to 5
gsm.
Materials for the Carrier Layer
[0229] The carrier layer 17 may be selected from the group
consisting of nonwovens, tissues, or films and combinations
thereof.
[0230] Examples of a nonwoven web used for the carrier layer 17 may
include various types of known nonwoven webs such as a spunbonded
nonwoven web, a meltblown nonwoven web, an a
spunbond-meltblown-spunbond nonwoven web. These nonwoven webs are
made of thermoplastic polymers.
[0231] A material for fibers composing the nonwoven web used for
the carrier layer 17 may include various types of known fibers such
as polyethylene, polypropylene, polyester, and acryl, conjugate
fibers such as polyethylene/polypropylene,
polyethylene/polyethylene terephthalate, and
polypropylene/polyethylene terephthalate, i.e., fibers formed of
core-in-sheath fibers and side-by-side fibers. The fibers may be
used alone or in combination. Further, the carrier layer 17 may
have a monolayer structure or a multilayer structure.
[0232] The carrier layer 17 may comprise a tissue made of wet-laid
fibers comprising cellulose fibers having a Wet burst Strength from
50 to 500 g according to the Wet Burst Strength Test Method and
combinations thereof.
[0233] The carrier layer 17 may be treated with a surfactant to
render the carrier layer 17 hydrophilic. The carrier layer 17 may
be made of one material of the group as set out above, which has
been chemically modified to render it hydrophilic. The hydrophilic
carrier layer 17 may thus improve the transfer of the liquid bodily
exudates from the distribution layer 54 to the absorbent core 28 of
the absorbent article 20.
[0234] The carrier layer 17 may have a basis weight of at least 5
gsm to 60 gsm or at least 5 gsm to 20 gsm or at least 5 to 15
gsm.
[0235] The carrier layer 17 may be wider and longer than the
distribution layer 54. The carrier layer can help preventing the
dry-laid fibers 540 getting to the skin of the wearer when the
distribution layer 54 comprises dry-laid fibers 540 and if the
topsheet/acquisition layer laminate 245 comprises some holes.
[0236] The carrier layer 17 may be colored. Color may be imparted
to the carrier layer 17 by color pigmentation. The term "color
pigmentation" encompasses any pigments suitable for imparting a
non-white color to the carrier layer 17. This term therefore does
not include "white" pigments such as TiO.sub.2 which are typically
added to the layers of conventional absorbent articles to impart
them with a white appearance. Pigments are usually dispersed in
vehicles or substrates for application, as for instance in inks,
paints, plastics or other polymeric materials.
[0237] The pigments may for example be introduced in a
polypropylene masterbatch. A masterbatch comprises a high
concentration of pigment and/or additives which are dispersed in a
carrier medium which can then be used to pigment or modify the
virgin polymer material into a pigmented bicomponent nonwoven. An
example of suitable colored masterbatch material that can be
introduced is Pantone color 270 Sanylen violet PP 42000634 ex
Clariant, which is a PP resin with a high concentration of violet
pigment. Typically, the amount of pigments introduced by weight of
the carrier layer 17 may be of from 0.3%-2.5%.
[0238] Alternatively, color may be imparted to the carrier layer 17
by way of impregnation of a colorant into the substrate. Colorants
such as dyes, pigments, or combinations may be impregnated in the
formation of substrates such as polymers, resins, or nonwovens. For
example, the colorant may be added to molten batch of polymer
during film, fiber, or filament formation.
[0239] When viewing the absorbent article from the topsheet, the
colored carrier layer 17 may provide to a caregiver an enhanced
impression of depth to support to the impression given by the
three-dimensional protrusions 250 as such, as long as the colored
carrier layer 17 are visible from the topsheet 24. Hence, a colored
carrier layer 17 can support the caregiver's perception that the
absorbent article is well able to absorb the liquid bodily
exudates.
[0240] The topsheet 24 and/or acquisition layer 52 of the
topsheet/acquisition layer laminate 245 may be colored, for the
same reasons.
[0241] The carrier layer 17 may be porous, may have a relatively
high permeability and have a relatively high level of saturation
when exposed to fluid under suction pressures, e.g. of 20 cm of
water. The relatively high level of saturation of the carrier layer
17 can be defined as the ratio between the volume of liquid bodily
exudates in the pores of the carrier layer 17 and the total void
volume of the carrier layer 17. The carrier layer 17 can help
providing connectivity between the acquisition layer 52 of the
topsheet/acquisition layer laminate 245 and the distribution layer
54.
[0242] Also, the carrier layer 17 may comprise some relative small
sized holes such that the dry-laid fibers 540 of the dry-laid
fibrous structure of the distribution layer 54 may partially pass
through the holes of the carrier layer. Hence, the dry-laid fibers
540 of the dry-laid fibrous structure can entangle and contact the
acquisition layer 52 of the topsheet/acquisition layer laminate
245. The carrier layer 17 may comprise holes having a size from
0.02 mm to 10 mm.
Example
[0243] The topsheet and the acquisition layer were attached to each
other with a hot melt adhesive applied in form of spirals with a
basis weight of 5 gsm. The acquisition layer was centered onto the
topsheet with respect to the topsheet and placed 50 mm from the
front MD edge of the topsheet. The topsheet and acquisition layer
attached together form a composite web.
[0244] The topsheet and acquisition layer attached together have
been simultaneously mechanically deformed by passing them between a
pair of intermeshing rolls (211, 212), see for example FIG. 17. The
topsheet of the topsheet/acquisition layer laminate was in contact
with the first intermeshing roll 211. The acquisition layer of the
topsheet/acquisition layer laminate was in contact with the second
intermeshing roll 212. The ridges and grooves have a triangular
shaped cross-section, as exemplified in FIG. 18A. The pitch P of
the rolls is 0.100 inch (2.5 mm) The second intermeshing roll 212
has discrete teeth 217 arranged in a staggered pattern. The teeth
217 have a uniform circumferential length dimension TL of about
0.195 inch (4.9 mm), are uniformly spaced from one another
circumferentially by a distance TD of 0.162 inch (4.1 mm), and have
a tooth height TH of about 0.270 inch (10.6 mm) The long sides of
the teeth have a side wall angle of about 5 degrees from vertical,
and the leading and trailing edges of the teeth have vertical side
walls. The first intermeshing roll 211 has continuous ridges 215
with a height of about 0.270 inch (10.6 mm) The topsheet attached
to the acquisition layer was intermeshed between the first and
second intermeshing roll (211, 212) at 0.135 inch (3.43 mm) depth
of engagement (DOE).
[0245] The topsheet of the topsheet/acquisition layer laminate was
a hydrophilic coated mono component high elongation spunbond
polypropylene (HES PP) nonwoven material with a density of 0.11
g/cm.sup.3. The mono component HES PP nonwoven material for the
topsheet has an overall basis weight of 20 gsm. The mono component
HES PP nonwoven material was first coated with a finish made of a
fatty acid polyethylene glycol ester for the production of a
permanent hydrophilic mono component HES PP nonwoven material. The
topsheet of the topsheet/acquisition layer laminate had a width of
168 mm and a length of 488 mm.
[0246] The acquisition layer of the topsheet/acquisition layer
laminate was a spunbond nonwoven with a basis weight of 60 gsm with
a density of 0.13 g/cm.sup.3. The acquisition layer comprises 7
denier PET/coPET (polyethylene terephthalate) trilobal bicomponent
fibers with a 70/30 ratio of PET/coPET which has been treated with
a surfactant. The acquisition layer of the topsheet/acquisition
layer laminate had a width of 90 mm and a length of 338 mm.
[0247] The carrier layer was a co-PET/PET tipped-trilobal
bicomponent fibers with a 90/10 ratio of PET/coPET. The basis
weight of the carrier layer was 17.7 gsm. The carrier layer had a
width of 168 mm and a length of 250 mm.
Prototype Diapers for the Example
[0248] Diaper prototypes for the above Example were produced using
Pampers Premium Care S4 (size 4) diaper commercially available in
Russia from October 2011 to October 2012. Pampers Premium Care S4
(size 4) diaper comprises a topsheet, an acquisition layer beneath
the topsheet, a distribution layer beneath the acquisition layer,
an absorbent core between the distribution and a backsheet beneath
the absorbent core. Diaper prototypes for the above Example were
produced using Pampers Premium Care S4 (size 4) diaper.
[0249] The topsheet and acquisition layer attached together for
each example were placed on top of a Pampers Premium Care S4 (size
4) from where the commercial topsheet and acquisition layer were
removed while keeping the distribution layer in place. For each
diaper prototype based on the above Example, the
topsheet/acquisition layer laminate were placed on top of the
distribution layer with the three-dimensional protrusions
protruding towards the backsheet.
[0250] A hot melt adhesive in form of spirals with a basis weight
of 5 gsm was applied on the surface of the carrier layer facing the
acquisition layer of the topsheet/acquisition layer laminate. The
acquisition layer front edge is placed 10 mm from the distribution
layer front edge. The topsheet/acquisition layer laminate attached
to the carrier layer was attached onto the distribution layer and
the absorbent core with a hot melt adhesive applied all over the
side of the carrier layer and the topsheet facing the distribution
layer. The hot melt adhesive was applied in form of spirals with a
basis weight of 5 gsm.
[0251] The three-dimensional protrusions of the
topsheet/acquisition layer laminate were protruding towards the
backsheet because the topsheet of the topsheet/acquisition layer
laminate was in contact with the male roll, as set out above.
[0252] Each prototype diaper was compacted in a bag at an In Bag
Stack Height, i.e. the total caliper of 10 bi-folded diapers, of 90
mm for 1 week. Then the bag was opened and the diapers out of the
bag were conditioned at least 24 hours prior to any testing at
23.degree. C.+/-2.degree. C. and 50%+/-10% Relative Humidity
(RH).
[0253] The measured protrusion height and the measured protrusion
base width of the three-dimensional protrusions of the
topsheet/acquisition layer laminate have been measured according to
the respective Protrusion Height and Protrusion Base Width Test
Methods (Table 1).
TABLE-US-00001 TABLE 1 Measurements of the protrusion height and
the protrusion base width of the three-dimensional protrusions
Measured Protrusion Measured Protrusion Replicate Height (mm) Base
Width (mm) average 1.40 2.00 Standard 0.0 0.1 deviation
Test Methods
Wet Burst Test Method
[0254] The Wet Burst Strength as used herein is a measure of the
ability of a fibrous structure to absorb energy, when wet and
subjected to deformation with regard to the plane of the fibrous
structure.
[0255] The wet burst strength of a fibrous structure (referred to
as "sample" within this test method) is determined using an
electronic burst tester and specified test conditions. The results
obtained are averaged out of 4 experiments and the wet burst
strength is reported for a fibrous structure 55 consisting of one
single layer of wet-laid fibers.
Equipment
[0256] Apparatus: Burst Tester--Thwing-Albert Vantage Burst Tester
or equivalent ball burst instrument where the ball moves downward
during testing. Refer to manufacturer's operation and set-up
instructions. The ball diameter is 1.59 cm and the clamp opening
diameter is 8.9 cm.
[0257] Calibration Weights--Refer to manufacturer's Calibration
instructions
[0258] Conditioned Room Temperature and Humidity controlled within
the following limits for Laboratory testing: [0259] Temperature:
23.degree..+-.1.degree. C. [0260] Relative humidity: 50%.+-.2%
[0261] Paper Cutter--Cutting board, 600 mm size
[0262] Scissors--100 mm, or larger
[0263] Pan--Approximate Width/Length/Depth: 240.times.300.times.50
mm, or equivalent
[0264] Distilled water at the temperature of the conditioned room
used
Sample Preparation
[0265] The fibrous structure 55 may be unwound from the roll. The
samples to be tested are conditioned in the conditioned room for 24
hours immediately before testing. All testing occurs within the
conditioned room. Cut the samples so that they are approximately
228 mm in length and width of approximately 140 mm in width.
Operation
[0266] Set-up and calibrate the Burst Tester instrument according
to the manufacturer's instructions for the instrument being used.
Holding the sample by the narrow edges, the center of the sample is
dipped into a pan filled approximately 25 mm from the top with
distilled water. The sample is left in the water for 4 (.+-.0.5)
seconds. The excess water is drained from the sample for 3
(.+-.0.5) seconds holding the sample in a vertical position. The
test should proceed immediately after the drain step. The sample
should have no perforations, tears or imperfections in the area of
the sample to be tested. If it does, start the test over. The
sample is placed between the upper and lower rings of the Burst
Tester instrument. The sample is positioned centered and flat on
the lower ring of the sample holding device in a manner such that
no slack in the sample is present. The upper ring of the pneumatic
holding device is lowered to secure the sample. The test is
started. The test is over at sample failure (rupture) i.e., when
the load falls 20 g from the peak force. The maximum force value is
recorded. The plunger will automatically reverse and return to its
original starting position. The upper ring is raised in order to
remove and discard the tested sample. The procedure is repeated
until all replicates have been tested.
Calculation
[0267] Wet Burst Strength=sum of peak load readings/number of
replicates tested
Report the Wet Burst results to the nearest gram.
Protrusion Base Width and Protrusion Height Test Methods
[0268] 1) General Information
[0269] The Measured Protrusion Base Width and Measured Protrusion
Height of the three-dimensional protrusions of the
topsheet/acquisition layer laminate of an absorbent article are
measured using a GFM Primos Optical Profiler instrument
commercially available from GFMesstechnik GmbH, Warthestra.beta.e
21, D14513 Teltow/Berlin, Germany. Alternative suitable
non-touching surface topology profilers having similar principles
of measurement and analysis, can also be used, here GFM Primos is
exemplified.
[0270] The GFM Primos Optical Profiler instrument includes a
compact optical measuring sensor based on a digital micro mirror
projection, consisting of the following main components: [0271] a)
DMD projector with 800.times.600 direct digital controlled
micro-mirrors [0272] b) CCD camera with high resolution
(640.times.480 pixels) [0273] c) Projection optics adapted to a
measuring area of at least 30.times.40 mm [0274] d) Recording
optics adapted to a measuring area of at least 30.times.40 mm
[0275] e) A table tripod based on a small hard stone plate [0276]
f) A cold light source (an appropriate unit is the KL 1500 LCD,
Schott North America, Inc., Southbridge, Mass.) [0277] g) A
measuring, control, and evaluation computer running ODSCAD 6.3
software
[0278] Turn on the cold-light source. The settings on the
cold-light source are set to provide a color temperature of at
least 2800K.
[0279] Turn on the computer, monitor, and open the image
acquisition/analysis software. In the Primos Optical Profiler
instrument, select "Start Measurement" icon from the ODSCAD 6.3
task bar and then click the "Live Image button".
[0280] The instrument is calibrated according to manufacturer's
specifications using calibration plates for lateral (X-Y) and
vertical (Z). Such Calibration is performed using a rigid solid
plate of any non-shiny material having a length of 11 cm, a width
of 8 cm and a height of 1 cm. This plate has a groove or machined
channel having a rectangular cross-section, a length of 11 cm, a
width of 6.000 mm and an exact depth of 2.940 mm. This groove is
parallel to the plate length direction. After calibration, the
instrument must be able to measure the width and depth dimensions
of the groove to within .+-.0.004 mm.
[0281] All testing is performed in a conditioned room maintained at
23.+-.2.degree. C. and 50+/-10% relative humidity. The surface to
be measured may be lightly sprayed with a very fine white powder
spray. Preferably, the spray is NORD-TEST Developer U 89, available
from Helling GmbH, Heidgraben, Germany.
[0282] 2) Protrusion Base Width Test Method
[0283] The topsheet/acquisition layer laminate is extracted from
the absorbent article by attaching the absorbent article to a flat
surface in a taut planar (i.e. stretched planar) configuration with
the topsheet of the topsheet/acquisition layer laminate facing up.
Any leg or cuff elastics are severed in order to allow the
absorbent article to lie flat. Using scissors, two longitudinal
cuts are made through all layers above the absorbent core (i.e. the
core wrap) along the edges of the topsheet/acquisition layer
laminate. Two transversal cuts are made through the same layers
following the front and back waist edges of the absorbent
article.
[0284] The topsheet/acquisition layer laminate and any other layers
above the absorbent core are then removed without perturbing the
topsheet/acquisition layer laminate. Freeze spray (e.g. CRC Freeze
Spray manufactured by CRC Industries, Inc. 885 Louis Drive,
Warminster, Pa. 18974, USA), or equivalent aid may be used to
facilitate removal of the uppermost layers from the absorbent
article. The topsheet/acquisition layer laminate is then separated
from any other layers, including any carrier layer (e.g. a nonwoven
carrier layer, a tissue layer), using freeze spray if necessary. If
a distribution layer, e.g. a pulp containing layer is attached to
the topsheet/acquisition layer laminate, any residual cellulose
fibers are carefully removed with tweezers without modifying the
acquisition layer.
[0285] The topsheet/acquisition layer laminate with
three-dimensional protrusions (conditioned at a temperature of
23.degree. C..+-.2.degree. C. and a relative humidity of 50%.+-.10%
for at least 24 hours) namely "the specimen" is laid down on a hard
flat horizontal surface with the body-facing side upward, i.e. the
topsheet of the topsheet/acquisition layer laminate being upward.
Ensure that the specimen is lying in planar configuration, without
being stretched, with the specimen uncovered.
[0286] A nominal external pressure of 1.86 kPa (0.27 psi) is then
applied to the specimen. Such nominal external pressure is applied
without interfering with the topology profile measurement. Such an
external pressure is applied using a transparent, non-shining flat
Plexiglas.RTM. plate 200 mm by 70 mm and appropriate thickness
(approximately 5 mm) to achieve a weight of 83 g. The plate is
gently placed on top of the specimen, such that the center point of
the Plexiglas.RTM. plate is at least 40 mm away from any folds,
with the entire plate resting on the specimen. A fold corresponds
to a part of the absorbent article (e.g. the topsheet/acquisition
layer laminate) where the absorbent article has been folded for
packaging purposes.
[0287] Two 50 mm.times.70 mm metal weights each having a mass of
1200 g (approximate thickness of 43 mm) are gently placed on the
Plexiglas.RTM. plate such that a 70 mm edge of each metal weight is
aligned with the 70 mm edges of the Plexiglas.RTM. plate. A metal
frame having external dimensions of 70 mm.times.80 mm and interior
dimensions of 42 mm.times.61 mm, and a total weight of 142 g
(approximate thickness 6 mm), is positioned in the center of the
Plexiglas.RTM. plate between the two end weights with the longest
sides of the frame aligned with the longest sides of the plate.
[0288] If the specimen is smaller than 70.times.200 mm, or if a
large enough area without a fold is not present, or if an area of
interest is close to the edges of the specimen and can't be
analyzed with the Plexiglas and weights settings described above,
then the X-Y dimensions of the Plexiglas.RTM. plate and the added
metal weights may be adjusted to reach a nominal external pressure
of 1.86 kPa (0.27 psi) while maintaining a minimum 30.times.40 mm
field of view. At least 10 complete three-dimensional protrusions
of the specimen should be captured in the field of view of 30
mm.times.40 mm.
Position the projection head to be normal to the specimen surface
(i.e. to the topsheet of the topsheet/acquisition layer laminate).
Adjust the distance between the specimen and the projection head
for best focus. In the Primos Optical Profiler instrument, turn on
the button "Pattern" to make a red cross appear on the screen cross
and a black cross appears on the specimen. Adjust the focus control
until the black cross is aligned with the red cross on the screen.
Adjust image brightness then capture a digitized image. In the
Primos Optical Profiler instrument, change the aperture on the lens
through the hole in the side of the projector head and/or altering
the camera "gain" setting on the screen. When the illumination is
optimum, the red circle at the bottom of the screen labeled "I.O."
will turn green. Click on the "Measure" button.
[0289] The topology of the upper surface of the
topsheet/acquisition layer laminate specimen is measured through
the Plexiglas plate over the entire field of view 30 mm.times.40
mm. It is important to keep the specimen still stationary during
this time in order to avoid blurring of the captured image. The
image should be captured within the 30 seconds following the
placement of the Plexiglas plate, metal weights and frame on top of
the specimen.
[0290] After the image has been captured, the X-Y-Z coordinates of
every pixel of the 40 mm.times.30 mm field of view area are
recorded. The X direction is the direction parallel to the longest
edge of the rectangular field of view, the Y direction is the
direction parallel to the shortest edge of the rectangular field of
view. The Z direction is the direction perpendicular to the X-Y
plane. The X-Y plane is horizontal while the Z direction is
vertical, i.e. orthogonal to the X-Y plane.
[0291] These data are smoothed and filtered using a polynomial
filter (n=6), a median filter 11 pixels by 11 pixels, and a
structure filter 81 pixels by 81 pixels. The polynomial filter
(n=6) approximates the X-Y-Z coordinate surface with a polynomial
of order 6 and returns the difference to the approximated
polynomial. The median filter 11 pixels by 11 pixels divides the
field of view (40 mm.times.30 mm) in X-Y squares of 11 pixels by 11
pixels. The Z coordinate of the pixel located at the center of a
given 11 pixels by 11 pixels square will be replaced by the mean Z
value of all the pixels of this given square. The structure filter
81 pixels by 81 pixels, removes the waviness of the structure and
translates all the Z peak values belonging to the bottom surface of
the Plexiglas plate to a top X-Y plane.
[0292] A Reference Plane is then defined as the X-Y plane
intercepting the surface topology profile of the entire field of
view (i.e. 30 mm.times.40 mm), 100 microns below this top X-Y
plane. In the Primos Optical Profiler instrument, to measure the
Material Area of the Reference Plane (Z=-0.1 mm), click on the
button "Evaluate". Then, apply a pre-filtering routine including a
polynomial filter (n=6), a median filter 11 by 11 and a structure
filter (n=81) using the function "Filter". Save the image to a
computer file with ".omc" extension.
[0293] The same above procedure is then executed on the
topsheet/acquisition layer laminate with the garment-facing side
upward (i.e. the acquisition layer of the topsheet/acquisition
layer laminate being upward), the 40 mm.times.30 mm field of view
being located at the exact same X-Y position of the
topsheet/acquisition layer laminate.
[0294] The Empty Area of the reference plane can be defined as the
area of the Reference Plane that is above the surface profile. The
Empty Areas having boundaries strictly located inside the field of
view area (i.e. 30 mm.times.40 mm) without crossing or overlapping
with the boundaries of the field of view area (i.e. 40 mm.times.30
mm) are defined as Isolated Empty Area(s). The Measured Protrusion
Base Width is defined for an Isolated Empty Area as the diameter of
the biggest circle that can be inscribed inside a given Isolated
Empty Area. This circle should only overlap with the Isolated Empty
Area.
[0295] In the Primos Optical Profiler instrument, this can be done
by clicking on "Draw circle" and drawing the biggest inscribed
circle possible in a chosen Isolated Empty Area. Click on "Show
sectional picture", the circle diameter can be measure via clicking
on the extremity of the sectional picture profile and then clicking
on "Horizontal distance" to obtain the Protrusion Base Width.
[0296] For both of the acquired and digitized images, the
Protrusion Base Width of all the Isolated Empty Areas is
determined. Then, the Measured Protrusion Base Width is calculated
as the arithmetic average of the 6 biggest Protrusion Base
Widths.
[0297] 3) Protrusion Height Test Method
[0298] The topsheet/acquisition layer laminate is extracted from
the absorbent article as described above in the Protrusion Base
Width Test Method.
[0299] The topsheet/acquisition layer laminate specimen comprising
three-dimensional protrusions is then conditioned and scanned under
a pressure of 1.86 kPa (0.27 psi) with the body-facing side upward,
i.e. the topsheet of the topsheet/acquisition layer laminate being
upward as described above in the Protrusion Base Width Test
Method.
[0300] After the image has been captured, the X-Y-Z coordinates of
every pixel of the 40 mm.times.30 mm field of view area are
recorded and smoothed/filtered as described above in the Protrusion
Base Width Test Method. A reference plane is also defined as
described above in the Protrusion Base Width Test Method.
[0301] In the Primos Optical Profiler instrument, to measure the
Material Area of the Reference Plane (Z=-0.1 mm), click on the
button "Evaluate". Then apply a pre-filtering routine including a
polynomial filter (n=6), a median filter 11 by 11 and a structure
filter (n=81) using the function "Filter". Save the image to a
computer file with ".omc" extension.
[0302] The same above procedure set out in the Protrusion Base
Width Test Method is then executed on the topsheet/acquisition
layer laminate with the garment-facing side upward (i.e. the
acquisition layer of the topsheet/acquisition layer laminate being
upward), the 40 mm.times.30 mm field of view being located at the
exact same X-Y position of the topsheet/acquisition layer
laminate.
[0303] The Empty Area of the reference plane can be defined as the
area of the Reference Plane that is above the surface profile. The
Empty Area having boundaries strictly located inside the field of
view area (i.e. 30 mm.times.40 mm) without crossing or overlapping
with the boundaries of the field of view area (i.e. 40 mm.times.30
mm) are defined as Isolated Empty Area(s). The Protrusion Height is
defined for an Isolated Empty Area as the distance between the
minimum Z value of the points of the topsheet/acquisition layer
laminate surface profile having X-Y coordinates located in this
Isolated Empty Area, and the Z value of the top X-Y plane.
[0304] Click on "Draw N parallel lines" and draw a first segment
parallel to the X axis of the field of view (direction of the
longest dimension of the field of view) passing through the center
of the Isolated Empty Area and extending outside the Isolated Empty
Area boundaries. The center of the Isolated Empty Area corresponds
to the middle of the segment parallel to the Y axis of the field of
view and joining the biggest and smallest Y value of the Isolated
Empty Area. Then input the "number" of lines to be drawn and set
the "distance" between lines to 0.05 mm. Enough lines need to be
drawn such to cover the entire Isolated Empty Area. Leave the
averaging parameter to 0 then click "Ok". Then click on "Show
sectional picture". Click on the point of the sectional picture
profile having the minimum Z value and click on "Vertical distance"
to obtain the Protrusion Height.
[0305] For both of the acquired and digitized images, the
Protrusion Height of all the Isolated Empty Areas is determined.
Then, the Measured Protrusion Height is calculated as the
arithmetic average of the 6 biggest Protrusion Heights.
[0306] 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."
[0307] Every document cited herein, including any cross referenced
or related patent or application, is hereby incorporated herein by
reference in its entirety unless expressly excluded or otherwise
limited. The citation of any document is not an admission that it
is prior art with respect to any invention disclosed or claimed
herein or that it alone, or in any combination with any other
reference or references, teaches, suggests or discloses any such
invention. Further, to the extent that any meaning or definition of
a term in this document conflicts with any meaning or definition of
the same term in a document incorporated by reference, the meaning
or definition assigned to that term in this document shall
govern.
[0308] 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.
* * * * *