DE9117294U1 - Absorbent hygiene article - Google Patents

Description

The registration of the GeVäuchgrouster ;: : underlying ¹ documents ·♦**··'

DIEHL · GLAESER HILTL & PARTNERS

CIVIL LAW COMPANY

Patent attorneys · Augustenstrasse 46 · D - 80333 Munich Dr. Hermann O. Th. Diehl · Graduate physicist Joachim W. Glaeser · Graduate engineer* Dr. Elmar HiItI ■ Graduate chemist Dr. Elisabeth Engelhard ■ Graduate biologist Dr. Frank Schorr · Graduate physicist In cooperation with Diehl & Partner AG CH-7513 Silvaplana ■ Switzerland

Patent Attorneys ■ European Patent Attorneys Munich · Hamburg*

3 July 2000 K5535-DE-U-I

Kimberly-Clark Worldwide, Ine

401 North Lake Street
Neenah, Wisconsin 54956

USA

ABSORBENT HYGIENE PRODUCT

Law firm ■ Office: Munich

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Telephone ■ Telephone
(089)17 86 36-0

fax

(080)* 1 SK)33

(OSB)J &Idigr;&EEacgr;40 34

Facsimile EMAIL address:

Apsch/ift ■ Add/e^s
£ugji$te/istrasj;e H-6*
D"803SS MCtncUen

Postal address ■ Mailing address P.O. Box 34 01 15 D - 80098 Munich

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K5535-DE-U-I

ABSORBENT HYGIENE ARTICLE This invention relates to children's diaper pants.

Conventional absorbent articles such as diapers, diaper pants, adult incontinence garments and others generally employ a thermoplastic film as the liquid-impermeable bottom layer or bottom sheet of the article. Various elastic systems in the leg and waist areas are used to gather the article for fit and tightness. These elastic systems and an absorbent structure are generally placed between a liquid-impermeable thermoplastic bottom layer and a liquid-permeable top layer or top sheet. This type of bottom layer is therefore liquid-impermeable but plastic in feel and appearance.

Several bottom layer developments have attempted to displace as much of the feel and appearance of plastic as possible. One such bottom layer development is a film-coated nonwoven. This bottom layer comprises a thermoplastic film which is extruded onto a nonwoven web. The heat of the film and the pressure applied during the process create the bond between the film and the nonwoven layer. While the film helps maintain the integrity of the nonwoven layer, it also contributes to a stiffer and less desirable bottom layer.

Another bottom layer development laminates the thermoplastic film to the nonwoven layer. The lamination is achieved by applying an adhesive to the film or

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the nonwoven layer and by subsequently attaching one layer to the other layer. Therefore, in both this second and the first development mentioned above, the thermoplastic film and the nonwoven layer are completely bonded along their facing surfaces.

To overcome such disadvantages, the invention provides an absorbent article according to independent claim 1. Further advantageous features and details of the absorbent article emerge from the dependent claims, the description and the drawings.

In particular, the invention provides an absorbent article which includes multiple deflections between the bottom layer and the absorbent structure to maintain the cloth-like nature of the bottom layer while providing liquid impermeability.

The present invention generally comprises an absorbent article which in turn comprises a top layer, an absorbent structure and a bottom layer. A material diverter layer is disposed between the absorbent structure and the bottom layer and is made of a material which is liquid impermeable but which may be vapor permeable. The diverter layer is not continuously bonded to the bottom layer in predetermined areas, thereby resulting in an absorbent article which has a more cloth-like texture.

The above-mentioned and other features and objects of this invention and the manner in which they are achieved will become more apparent and the invention itself will be better understood when reference is made to the following description of an embodiment of the invention

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in conjunction with the accompanying drawings, whereby:

Fig. 1 is a perspective view of an absorbent article incorporating the principles of the present invention;

Fig. 2 is a perspective, fragmentary view of a portion of the absorbent article incorporating the principles of the present invention; and

Figure 3 is a cross-sectional view of a portion of the absorbent article incorporating the principles of the present invention.

The present invention provides several unique features for an absorbent article. One of these key features is a bottom layer which has an improved cloth-like texture. A second feature is the provision of a liquid-impermeable baffle between the absorbent structure and the bottom layer which is discontinuous or only partially attached to the bottom layer, thereby reducing the stiffness or rigidity that would be caused by completely bonding the bottom layer to the baffle layer. A third feature of the present invention is the provision of a multi-part baffle which need not extend uninterruptedly across the surface area of the bottom layer or absorbent structure.

Referring to Fig. 1, there is shown a child's diaper pant 2 which generally comprises a waist opening 4, leg openings 6, a central absorbent structure 8 and stretchable side panels 10 connected to the absorbent structure 8 to form the waist opening 4 and a leg opening 6. If desired, the stretchable

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able side panels 10 may be omitted and replaced by continuing or extending all or only parts of the absorbent structure 8, which is then joined along the seams 12 to form the waist opening 4 and the leg openings 6.

Referring to Figure 2, a portion of the absorbent structure 8 is shown as generally hourglass-shaped, which may be the shape of the absorbent structure for the diaper pant 2 or, for example, may be a portion of the absorbent structure for a baby diaper. The bottom layer 14, which may be made from any suitable liquid permeable nonwoven web, has a liquid impermeable baffle layer 16 laid thereon. Shown in dashed lines is a shape of the absorbent structure 18 that would be laid on top of the baffle layer 16. This sandwiches the baffle layer 16 between the bottom layer 14 and the absorbent structure 18.

The bottom layer 14 and the liquid-impermeable deflection layer 16 are intermittently or only partially bonded to each other in predetermined regions depending on the size and type of absorbent article such that the common central regions 15, 17 of the bottom layer 14 and the deflection layer 16 are not bonded to each other, i.e. are freely movable relative to each other. As an example, Fig. 2 illustrates a plurality of adhesive tracks 20 bonding the adjacent peripheral regions of the bottom layer 14 and the deflection layer 16 in an intermittent manner. Therefore, the facing surfaces of the bottom layer 14 and the deflection layer 16 lying within the adhesive tracks 20 can move relative to each other, as can the central regions 15, 17. This freedom of movement between the nonwoven bottom layer 14 and the deflection layer 16 creates the enhanced cloth-like feel for the absorbent article.

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Fig. 2 also illustrates leg elastics 22 inserted on both sides and between the bottom layer 14 and the deflection layer 16. By inserting the leg elastics 22 in a stretched state between the bottom layer 14 and the deflection layer 16, not only is the discontinuous connection of the bottom layer 14 to the deflection layer 16 created, but a gather or elastic gather is also incorporated into the article.

Referring now to Fig. 3, a cross-sectional view of an absorbent article incorporating the present invention is shown. The bottom layer 14 and the deflection layer 16 are joined together along their peripheral edges by the leg elastics 22, the insertion of which serves to connect the bottom layer 14 to the deflection layer 16 and also provides elasticity along the edges. If desired, the additional adhesive tracks 20 can be provided either in the plane or out of the plane of the leg elastics 22, and in Fig. 3 the adhesive tracks 20 are shown in the plane of the leg elastics 22. Alternatively, if additional adhesive tracks 20 are provided, the leg elastics 22 can be added on the side of the deflection layer 16 opposite the bottom layer 14, which would locate the leg elastics 22 generally between the deflection layer 16 and the top layer 24. Disposed on the deflection layer 16 is the absorbent structure 18 which is also covered with the liquid permeable cover layer 24. The cover layer 24 is connected to the deflection layer 16 and the bottom layer 14 in any suitable manner. As can be seen from Fig. 3, there is no attachment between the bottom layer 14 and the deflection layer 16 between the adhesive tracks 20, whereby the bottom layer 14 has freedom of movement during the placement of the absorbent article on the wearer and during the body movements of the wearer. This

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Freedom of movement creates an additional fabric-like feel or texture to the article, which is highly desirable both for the wearer and, in the case of diapers and diaper pants, for mothers as well.

Although Fig. 2 shows a baffle layer 16 coextensive with the bottom layer 14 and also shows the absorbent structure 18 lying within the peripheral boundaries of both the bottom layer 14 and the baffle layer 16, various configurations are contemplated by the invention. For example, the baffle layer 16 can be resized to be actually smaller than the absorbent structure 18 so that selected portions of the absorbent structure 18 lie directly adjacent to the breathable bottom layer 14. The baffle layer 16 can also be a plurality of strips or layers of baffle material, rather than just a single layer as shown. For example, the deflection layer 16 may comprise a relatively small rectangular layer disposed only in the central region 17 between the absorbent structure 18 and the bottom layer 14, and a plurality of strips or segments of deflection material disposed at preferred locations between the absorbent structure 18 and the bottom layer 14.

Various arrangements for securing the deflection layer 16 to the bottom layer 14 are also contemplated by the present invention. For example, the adhesive tracks 20 may be a continuous adhesive track along the peripheral areas between the bottom layer 14 and the deflection layer 16. Alternatively, the deflection layer 16 and the bottom layer 14 may be joined together by a plurality of adhesive tracks running substantially parallel to each other in either the machine direction or the cross direction, or they may be joined together by a plurality of intersecting adhesive tracks providing a grid-like appearance. The type

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the offset attachment between the deflection layer 16 and the bottom layer 14 is generally determined by the type of garment, the size of the garment, and the materials from which the deflection layer 16 and the bottom layer 14 are made.

The bonded or joined surface area between the bottom layer 14 and the deflection layer 16 is preferably between about 1% to about 30% of the facing surface area between the bottom layer 14 and the deflection layer 16, more preferably between about 1% to about 15%.

The deflection layer 16 may be made of any suitable liquid impermeable material and is preferably a polypropylene or polyethylene film having a thickness of about 25.4 µm (about 1.0 mil), although thicknesses greater than 5.08 µm (0.20 mil) are suitable. The deflection layer 16 may also be made of materials suitably treated or treated to be liquid impermeable. Examples include meltblown or film materials made of polypropylene or polyolefin copolymers such as ethylene vinyl acetate, ethylene methyl acrylate, ethylene ethyl acrylate, polyvinyl chloride, and the like. The deflection layer 16 may also be made of a material that is both liquid impermeable and vapor permeable. As a breathable, ie liquid impermeable, vapor permeable material, the deflection layer 16 has a water vapor transmission rate of at least about 2,000 g/m ² /24 hours. Preferably, the deflection layer 16 has a water vapor transmission rate of at least about 4,000 g/m 2 /24 hours, and more preferably a value of at least about 5,000 g/m ² /24 hours. The deflection layer 16 can also be selectively breathable in that areas are breathable while other areas are impermeable.

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for both liquid and vapor. It is preferred that the breathable area of the baffle layer 16 be about 20 cm ² or more.

A breathable baffle layer 16 may comprise a microporous polymer film such as Grade TMP-I film manufactured by Mitzui Toatsu Chemical Inc., Tokyo, Japan, or a nonwoven material such as a spunbond or meltblown web composed of synthetic polymer fibers treated to be liquid impermeable and vapor permeable.

Both the topsheet 24 and the breathable bottomsheet 14 may be made from similar or different materials that are liquid permeable, such as a spunbond web composed of synthetic polymer fibers; a spun-entangled web; an adhesive-carded web composed of synthetic polymer fibers, and the like. Suitable synthetic polymers are polyethylene, polypropylene, polyester, and nylon. In one embodiment, the polymer filaments have a denier in the Tex system within the range of about 0.167 (1.5) to about 0.778 (7) Tex (d). The filaments are arranged to form a layer having a basis weight within the range of about 10 grams/m to about 35 grams/m.

The absorbent structure 18 may comprise various types and mixtures of fibrous material. For example, the absorbent structure 18 may comprise cellulose fluff, synthetic fibers, absorbent gel material in the form of particles, fibers, sheets, and the like, and in various blends and mixtures thereof.

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Claims (9)

1. Children’s disposable diaper pants, comprising:
an absorbent article ( 8 ) comprising a liquid-permeable top layer ( 24 ), a liquid-permeable nonwoven bottom layer ( 14 ), an absorbent body ( 18 ) disposed between the top layer ( 24 ) and the bottom layer ( 14 ), seams ( 12 ) forming a waist opening ( 4 ) and a pair of leg openings ( 6 ) and
a completely liquid-impermeable deflection layer ( 16 ) disposed between the bottom layer ( 14 ) and the absorbent body ( 18 ), the absorbent body lying within the peripheral contours of both the bottom layer ( 14 ) and the deflection layer ( 16 ), the liquid-impermeable deflection layer ( 16 ) and the bottom layer ( 14 ) being connected to one another by a continuous adhesive track or interrupted adhesive tracks along their adjacent peripheral regions so that their common central portions ( 15 , 17 ) move freely relative to one another. 2. A diaper pant according to claim 1, wherein stretchable side panels (10) are assembled to the absorbent structure ( 8 ) and the seams ( 12 ) connect the side panels ( 10 ) to form the waist opening ( 4 ) and the pair of leg openings ( 6 ). 3. Diaper pants according to any one of the preceding claims, wherein the bottom layer ( 14 ) and the deflection layer ( 16 ) are congruent. 4. A diaper pant according to any one of the preceding claims, wherein the deflection layer ( 16 ) is smaller in dimensions than the bottom layer ( 14 ). 5. Diaper pants according to any one of the preceding claims, wherein the deflection layer ( 16 ) is smaller in dimensions than the absorbent body ( 18 ). 6. The diaper pant of any preceding claim, wherein the diverting layer ( 16 ) is liquid impermeable and vapor permeable and has a water vapor transmission rate value of at least about 2,000 grams/square meter/24 hours. 7. The diaper pant of claim 6, wherein the deflection layer ( 16 ) is vapor permeable in selected portions thereof. 8. The diaper pant of claim 7, wherein the selected vapor permeable portions have a total area of about 20 square centimeters or more. 9. A diaper according to any one of the preceding claims, wherein the adhesive track is a strip of elastic material.