CN1253134C - Absorbent articles with means for achieving or maintaining convexo-concave bunching - Google Patents

Abstract

The present invention relates to a moisture-wicking article having a means of realizing or maintaining a convex-concave shape, wherein it has an upwardly convex (i.e., facing the wearer during use) central crotch portion and an outwardly convex portion located at the longitudinal end of the article, following the curve of the body around the waist.

Description

Absorbent articles having means for obtaining or maintaining convex-concave elevations

technical field

The present invention relates to hygienic absorbent articles, in particular absorbent articles for containing relatively large volumes of bodily fluids, such as urine and/or faecal discharges, such as adult incontinence products or baby diapers.

Background technique

Absorbent articles for use in the hygienic field are well known in the prior art. In addition, the shape of absorbent articles has also been discussed in depth, both with respect to the outer shape of the article (as opposed to, for example, a rectangle) and with respect to its three-dimensional shape.

In particular, feminine hygiene pads having improved body contact to receive bodily exudates have been disclosed by three-dimensionally shaping the article.

US-A-5,300,055 (Buell) discloses an absorbent article having an upwardly convex body-facing surface such that the entire article either has an "upside-down U" shape (i.e. the opening of the U faces away from the Orientation) or have a "W" shape. A similar article is described in WO 95/31165 (Olsen) where the "W"-shaped structure is obtained by means of elastic elements which are an integral part of the article.

In WO 95/17148 (Bergman) a sanitary napkin is disclosed which achieves better contact between the labia of the wearer and the article, thereby improving the handling of fluids (ie menses). Likewise, WO 88/04547 (Thoren) describes a sanitary napkin aimed at a direction oriented away from the wearer by securing elastic elements to the topsheet in the machine direction (MD) and in the cross-machine direction (CD). side to improve contact between the article and the wearer. In addition, EP-A-0302,523 (Lassen) describes an anatomically shaped feminine pad produced by molding, molding or other shaping techniques.

The fitting aspect of absorbent articles such as baby diapers is discussed in US-A-5,098,423 (Pieniak). The focus is on narrowing the width of the crotch, for example by folding the diaper in the crotch to 2x, 4x, 6x, 8x. This folding can be achieved by a so-called W-fold, whereby the absorbent article has a "W" shape. It does not disclose shaping or folding involving the core in the body part.

However, the prior art has not adequately considered the specific requirements and benefits of those moldings for adult incontinence products or baby diapers that have a relatively high volume of fluid discharge.

Moreover, the prior art fails to achieve the further benefit of specific shaping for articles intended to receive faeces.

Accordingly, there remains a need to improve the management of body exudates while improving the comfort of these articles.

Contents of the invention

It is therefore an object of the present invention to provide an absorbent article specifically designed to receive relatively large volumes of bodily exudates (such as urine) without thereby increasing undue discomfort to the wearer and without adversely affect the performance of the product.

Another object of the present invention is to provide such an article with additional improved handling of faeces.

Another object of the present invention is to provide a design that satisfies the above needs and can be conveniently applied to the wearer by himself or herself, or by others such as parents or caregivers.

The present invention relates to an absorbent article having means for achieving or maintaining a convex-concave shape, wherein there is a central crotch portion which is raised upwards (i.e., towards the wearer during use), and tight at the longitudinal ends of the article. The outward bulge around the waist that follows the curves of the body.

According to one aspect of the present invention, there is provided a disposable absorbent diaper for receiving urine and faeces, comprising: a topsheet, a backsheet and an absorbent core therebetween; wherein said core comprises a front waist region and a rear a waist region, both of which are concavely shaped to conform to the body of the wearer; wherein the core includes a urine loading region having a convex raised shape upwardly towards the wearer; wherein, said raised dome is achieved by pre-folding the diaper along its longitudinal centerline at least in said urine loading zone such that at least some portions of the backsheet covering the absorbent core are in direct contact with each other; and said core further comprises free longitudinal edges comprising elastic members formed by folding the backsheet inwardly; the diaper further comprising one or more transition regions; and said transition region of the absorbent core forms at least one pocket located in a longitudinally rearwardly offset position.

Wherein said convex raised shape of the urine loading zone is formed by an adhesive applied externally to the backsheet.

Wherein said convex raised shape of the urine loading area is formed by mechanical engagement means, at least a portion of said means being positioned laterally spaced from a longitudinally extending centerline of said diaper.

Therein, said convex raised shape of the urine loading zone is achieved by elastically stretchable parts having at least a force component in a direction transverse to the machine direction.

Wherein said means for obtaining said convex hump shape of the urine loading zone are fixed on the lateral sides of said core and are not fixed in the centre.

wherein said diaper has length and width dimensions, and a z-direction perpendicular to both of said dimensions, wherein said means for obtaining a raised raised shape in the urine loading zone is an elastically stretchable member which There is at least a machine direction force component and at least one z direction force component which is oriented towards the wearer is applied during use.

Wherein, the diaper also includes a fixing device for fixing the diaper on the wearer's body.

Wherein, said fastening means comprises a belt and a lap area, which adhesively or mechanically fasten the front and rear waist regions of the diaper to each other.

Wherein said fastening means further comprises an elastic member for holding the diaper in position.

Wherein, the design capacity of the absorbent core is greater than about 70 milliliters of urine.

Description of drawings

Figure 1 shows an absorbent pad as an example of an absorbent article;

Figure 2a shows a thin-section cross-sectional view of the urine loading area of an article raised in the shape of an "Ω" according to the present invention;

Figure 2b shows a cross-sectional view of a thin section of a W-folded urine loading area in a prior art article for comparison.

Detailed ways

An absorbent article typically includes:

-- absorbent component (commonly referred to as core or core structure, which may consist of substructures);

-- "Body Part", e.g.

-- liquid-impermeable negatives;

-- Optional other structures such as closure parts

-- or elastic elements.

In the context of this specification, an absorbent article may be "unitary" (that is, all elements are joined together) such that the article is essentially one piece when in use; or the absorbent article may be composed of separate parts which may include items such as The absorbent part of the absorbent pad, and the external fastening part such as reusable stretch fastening underpants, for example, the combination of elastic pants and disposable absorbent pads often used in adult incontinence products.

In either case, the article or its components may be disposable or reusable. Accordingly, the term "disposable" as used herein means that these absorbent articles or components are not intended to be laundered or otherwise recycled or reused as absorbent articles or components thereof (i.e. are discarded, preferably recycled, composted, or otherwise disposed of in an environmentally compatible manner).

The absorbent article has a transverse direction (x-direction or width), which is defined as the direction parallel to the transverse centerline and aligned with the wearer's "left-to-right" direction in use; a longitudinal direction (y-direction or length) , defined as a direction parallel to the longitudinal centerline and aligned with the height direction of the wearer in a standing position during use; and an axial direction (z-direction or thickness), defined as the direction extending through the thickness of the diaper 20 .

In the context of the present invention, the term "concave" means an "outwardly convex" curve, that is, the general curve that a belt worn around the waist would exhibit, for example when following the general curve of the wearer's waist. Concave curve section. The term "convex" relates to opposite curved portions. Of course, these terms are relative, and are also associated with the terms "upward" and "downward" (following the usual understanding of gravity). Henceforth, the letter "U" means having a "convex downward" or concave shape. The Greek capital letter Ω (Omega) denotes a curved section with an "upward bulge" in the central section. If the terms "concave" and "convex" are used without specifying an "upward" or "downward" direction, the meaning is "upwardly". If these terms are used with respect to the position of the wearer, the wearer is assumed to be in a standing position unless otherwise specified.

The invention is illustrated in Figures la, b and c by depicting the absorbent component of an absorbent article (which may be a baby diaper or an adult incontinence pad).

The liner includes an absorbent core 10 for absorbing and containing fluids, which in most cases are primarily aqueous based fluids. The absorbent core 10 can be any absorbent device that is generally compressible, compliant and capable of absorbing and retaining primarily aqueous liquids. Examples of suitable absorbent materials include comminuted wood pulp, crepe fiber wadding; meltblown polymers; chemically hardened, modified or crosslinked cellulosic fibers; tissue paper including tissue bales and tissue laminates; absorbent foam ; absorbent sponges; superabsorbent polymers; absorbent gelling materials; or any equivalent material or combination of materials. The shape and structure of the absorbent pad can also vary (for example, the absorbent pad can have regions of different thicknesses, hydrophilic gradients, superabsorbent gradients, or acquisition zones of lower average density and smaller average basis weight; or include one or more layers or substructure). Preferably, the absorbent pad has a generally flat profile, thereby avoiding the complications of having a solid three-dimensionally formed structure.

US Patent No. 4,610,678 to Weisman et al. on September 9, 1986 entitled "High Density Absorbent Structure"; on June 16, 1987 to Weisman et al. US Patent No. 4,673,402 to Angstadt on December 19, 1989 entitled "Absorbent Core with Powder Layer"; US Patent No. 4,888,231 to Alemany et al. Density and low basis weight high density absorbent member" US Patent No. 4,834,735. Other absorbent pad designs are described in European Patent Application Nos. 93305150.0 and 93309614.1.

US Patent No. 4,411,660 discloses having two layers of different types of absorbent material in an absorbent product such that the top layer gels slower than the first layer.

European patent specification EP-B-0,401,189 discloses absorbent products with very good properties, which are realized by using two different types of absorbent gelling materials in each layer, instead of using two absorbent gelling materials in a single layer. A mixture of glue materials to achieve.

Hydrogel-forming absorbent polymers useful in the present invention include a variety of substantially water-insoluble but water-swellable polymers which have the ability to absorb large quantities of liquids. Such polymeric materials are also commonly referred to as "hydrocolloid" or "superabsorbent" materials. These hydrogel-forming absorbent polymers preferably have a high number of anionic functional groups, such as sulfonic acid and more typically carboxyl groups. Examples of polymers suitable for use herein include those prepared from polymerizable unsaturated acid-containing monomers. Thus, these monomers include olefinically unsaturated acids and anhydrides containing at least one carbon-to-carbon olefinic double bond. More specifically, these monomers may be selected from olefinically unsaturated carbonic acids and anhydrides, olefinically unsaturated sulfonic acids, and mixtures thereof.

As noted above, the hydrogel-forming absorbent polymers are preferably slightly network crosslinked. The network crosslinking acts to render the polymer substantially water-insoluble and, in part, determines the moisture absorption capacity and extractable polymer content characteristics of the precursor particles and the final formed macrostructure. The above-cited US Patent No. 4076663 and German Patent DE-A-4020780 (to Dahmen) describe in more detail the preparation of these network crosslinked polymers as well as commonly used network crosslinkers.

In order to be able to compare absorbent articles having different end use conditions, or articles of different sizes, "design capacity" has been found to be a suitable means.

For example, infants represent a typical user group, but even within this group, on the one hand, from younger infants (newborns) to toddlers, the amount of urination, the frequency of loading, and the composition of the urine are large. as different, but also for different individuals in, for example, a toddler.

Other user groups may be older children who still suffer from some degree of incontinence.

In addition, incontinent adults can use the device, again with a wider range of voiding conditions, typically ranging from mild incontinence to severe incontinence.

Henceforth, an absorbent article capable of meeting these requirements should have the capacity to absorb a certain amount of urine, referred to for purposes of further discussion as the "design capacity" (discussed in more detail below).

Such displacements of fluid must be absorbed by the material that ultimately stores these bodily exudates (at least the water therein) so that very little, if any, remains on the wearer's skin-facing surface of the absorbent article. The term "ultimate" means on the one hand that the absorbent article has been worn for an extended period of time, and on the other hand that absorbent materials have reached their "ultimate" capacity after reaching equilibrium with their surrounding environment. This can be either the actual use condition of such absorbent articles after a long period of wearing, or a condition in the test procedure carried out on simple materials or material components. Since many of the steps under consideration have asymptotic dynamics, when the actual capacity reaches a value sufficiently close to the end of the asymptote (for example, relative to the measurement accuracy of the instrument), one skilled in the art can easily It is recognized that the "final" capacity will be reached.

Since absorbent articles may include some materials that are primarily used for ultimate storage of liquids, and other materials that are primarily used to perform functions such as receiving and/or distributing liquids, but may also have some ultimate storage capacity, in There is no artificial separation of these functions in describing suitable absorbent core materials for the present invention. Nevertheless, it is still possible to determine not only the ultimate storage capacity of the entire absorbent core, of some regions of the absorbent core, of the absorbent structure, or even of a substructure, but also of the components used for these elements. storage capacity of the material.

Those skilled in the art will readily adopt appropriate design capacities for other target user groups, as discussed above for changing article sizes. For example, an adult incontinence product intended for severe incontinence patients may include 9 grams of superabsorbent material (which has an absorbent capacity of approximately 31 ml/g when subjected to the known tea bag centrifuge capacity test), and include 97 grams of conventional cellulose airfelt having a capacity of about 4 ml/gram, resulting in a total final storage capacity of about 667 ml. Other examples involve supplies for patients with mild incontinence. For example, the ATTENDS MINI type with a final storage capacity of 70 ml, the ATTENDS MINIPLUS type of 90 ml, or the ATTENDS NORMAL type of about 167 ml, all of which are distributed by the company Procter & Gamble in many countries in Europe.

Referring back to Figure 1, the absorbent core has waist regions 14, 15 adjacent the transverse sides 12, 13, and a crotch region 11 connecting these portions 14, 15, the crotch region having a minimum width "A". The width of the waist regions 14, 15 is approximately twice the width of the crotch region 11 as given in the example in FIG. 1a.

The absorbent core 10 is joined to a liquid impermeable backsheet 16 . The backsheet 16 may be made of a woven or nonwoven material, a polymeric film such as a thermoplastic film of polyethylene or polypropylene, or a composite material such as a film-coated nonwoven material. Typically, the backsheet is a thermoplastic film having a thickness of between about 0.012 mm (0.5 mil) and about 0.051 mm (2.0 mil), such as RR8220 (blown film) available from Tredegar Industries Inc. of Terre Haute, IN. and RR5475 (cast film) for blown or cast polyethylene (PE) films. Such backsheet 16 is preferably embossed and/or matte finished to provide a more cloth-like appearance.

Furthermore, it is generally preferred that the backsheet 16 is both permeable to vapor transmission through itself and prevents liquid from passing through the backsheet 16.

The width and length dimensions of the backsheet 16 are greater than the dimensions of the absorbent core 10, thereby forming the outer perimeter. The portion of the backsheet 16 that extends longitudinally out of the core is referred to as the fin.

The wider longitudinal edges 17, 18 of the backsheet 16 are folded inwardly so as to at least partially cover the absorbent core 10. The free longitudinal sides 19, 20 contain elastic members 21, 22 (eg elastic bands or strips). When the absorbent article is stretched outward as shown in Figure 1, these elastic members are stretched so as to contract during use for a better body fit.

The longitudinal sides 17, 18 are now in a tubular arrangement 23, 24 with the unfolded part, so that the stretched elastic elements connected by their ends to the end sides 25, 26 are connected to 27, 28 of the inwardly folded longitudinal sides 17, 18 respectively. connect.

The topsheet 29 is positioned on the absorbent core 10 facing the wearer during use. The topsheet 29 is compliant and has a soft hand. Also, the topsheet 29 is liquid permeable, allowing exudates such as urine to readily pass through its entire thickness. A variety of materials can be used to make suitable top sheets, such as porous foams; reticulated foams; porous plastic films; or made of natural fibers (such as wood fibers or cotton fibers), synthetic fibers (such as polyester, polyethylene fibers, etc. woven or nonwoven mesh made of polymeric fibers), or a combination of natural fibers and synthetic fibers. The topsheet 29 can be produced using a variety of manufacturing techniques. For example, the topsheet 29 may be made of spunbonded, carded, wetted, hydroentangled, combinations of the above fibrous nonwovens, or other similar materials. A kind of topsheet that often uses is to be made (for example by Veratec Inc., a Division of International Paper Company, ofWalpole, Massachusetts produces) product designation P-8).

The topsheet is attached to substantially all or most of the surface of the absorbent core, or may be only partially bonded thereto. The topsheet may be apertured so that exudates such as urine or menses readily penetrate it. The topsheet can also be fully or partially elastic.

In order to retain the absorbent member on the body of the wearer, as described above, and in registration with the body opening through which bodily exudates escape, the absorbent article requires one or more fastening means.

Such fastening means can be of the mechanical type, that is, by using friction between the article and the wearer's skin or structural support (for example, conforming to the body contours of the wearer's hip bones) Overcomes the force of gravity and/or friction between the article and an external article such as the wearer's outerwear and/or bedding.

The absorbent member may also be held in place by conventional closure systems, such as an integral belt system formed by adhesive-coated straps or mechanically engaging elements, to secure the article or absorbent member around the waist of the wearer .

Thus, the absorbent article or absorbent component has a closure system consisting of strip-shaped panel fastening means and overlapping elements. The strap fastening means comprises an anchoring zone and a functional zone, and the bridging element is preferably a reinforcing strip or part of the backsheet. The feature can take various configurations such as adhesive fastening elements, mechanical fastening elements, a combination of adhesive and mechanical fastening elements, or any other means known to those skilled in the art.

For these closure systems that surround the waist of the wearer, the article preferably also includes elastic members selectively attachable to the closure structures to improve and maintain the fit of the article during use.

An absorbent article (sometimes referred to as a "pant-shaped diaper") is a one-piece article having a pant-like design (i.e., with closed side seams forming a fully enclosed structure in the waist region) and having elastic members to form elastic panties like the ones described above. The same fastening, additionally comprising an absorbent core (Pants comprising elastic portions are further described in European Patent Application No. 96112413.8 filed August 1, 1996).

Alternatively, an absorbent member as described above may simply have means for attaching it to the user's ordinary panties, such as is often used in thin feminine catamenial products (e.g. called "panty liners"), shown in Figure 1c is represented by the fixture 30 .

Another variant is to have fastening means of the glued top fixing type. As described in European Patent Application 9710666.91, the purpose of such "body adhesive" devices is to secure the article directly to the skin of the wearer.

Another embodiment of the present invention relates to non-unitary articles comprising an absorbent member and a separate fastening device or panties (such as mesh or stretch panties) which can be used either as a replacement for conventional underwear or as an adjunct to the wearer's Regular underwear comes up for use. A similar design for such a non-integral part is an attachable strap as described in EP-A-0.409.307 (Gipson et al.).

Additionally, an absorbent article according to the invention may have several of the aforementioned fastening means, for example both body adhesive applied to the absorbent part and an additional stretch member or an undergarment in a double fastening means arrangement.

In non-integral designs, both the absorbent member and the fastening member may be disposable, or one or both may be reusable (eg, after laundering).

        Ω-(Omega) shaped absorbent articles

In addition to the structures described above, the following embodiments make the invention particularly suitable for containing urine and/or fecal discharges.

The first and essential element is the formation of a raised bulge at least in the crotch region (particularly at least at the urine loading region or location) during application of the article to the wearer and/or during use. The urine loading zone is typically located slightly forward (ie typically about 5 cm) from the crotch point of the article, corresponding to the narrowest width dimension of the stiffest part of the article.

This raised bulge can be achieved by means disposed in the crotch region of the article, in particular at the urine loading region of the article, and the centerline of the article is positioned more closely than the lateral sides of the absorbent member during use. Closer to the wearer's body, and closer than in the flattened configuration, whereby its centerline is located closer to the wearer's body than the sides, so that the absorbent member actually bulges upwardly towards the wearer.

In Figure 2a, such an absorbent core 228 forms an upwardly convex shape (ie, the middle portion of an omega). The lower part of Ω (Omega) is formed by the main body component, ie mainly film and/or nonwoven backsheet material. This structure is called an "Ω-bump".

The omega-shaped raised absorbent core needs to extend at least about +/- 2.5 centimeters at least around the urine loading location, preferably towards the front and back of the article. For comfortable wearing, the convex crotch core should transition into the front and back waist portions of the article with concave curves so as to fit well around the wearer's waist.

Also located in the region of the lower part of omega are the elastic elements for keeping the sides of the article in contact with the wearer's legs.

Compared with the articles of "U" shape or W shape in the prior art, the articles of the present invention provide particular advantages; W shaped or folded.

The Omega protuberances of the present invention can form longitudinally shaped pockets on the outside of the absorbent member, which can provide certain benefits during use. Since the absorbent member will be loaded at its top "ridge" (230), on the one hand it will adequately absorb body exudates (because there is little room for fluid to go elsewhere); When using the same material and structure, gravity assists the fluid to penetrate into the receiving material, thereby minimizing the time the fluid stays on the surface, thereby minimizing the possibility of wetting the wearer's skin or leaking to the outside.

This advantage becomes even more pronounced when combined with a core structure having sub-optimal liquid handling properties. Even if the urine does not immediately seep into the article upon contact with the article, it will "flow" along the slope of the upwardly oriented raised portion (ie the slope of the Omega). If the core saturates (permanently or briefly) in the wetted area (which can happen with cores of poor performance or capacity), fluids that cannot penetrate into the core will be released by the liquid-impermeable sides of the Omega Intercepting, the side is maintained in a good seal against the wearer's garment by the liquid impermeable backsheet (216).

Another advantage can also be seen in Figures 2a and 2b, which show the absorbent core after absorbing a certain amount of urine. Approaching the expanded core represented by the expanded boundaries 240 and 242, in the case of a traditional "W-folded" core, the urine will fill the deeper part of the W, which almost forms a completely full cup (especially in under the impact of the wearer's motion). Especially for cores composed of superabsorbent materials, which tend to reduce the liquid permeability of the matrix containing these materials, due to the limitation of geometric expansion or due to the lack of fluid transport to these parts, will result in lower parts of W( In a direction away from the wearer) expansion is impeded.

However, in the case of the present invention, the core swells only at the convex bumps of the "Ω", essentially not impeding negatively fluid transport.

If combined with a high-performance core, the utility of the omega ridges for fluid handling also changes: now the requirement for transverse sealing becomes less important, but the "omega ridges" (230) provide flow in the CD direction by increasing The loading area in the CD direction increases the liquid uptake rate and can also significantly improve the longitudinal fluid distribution.

In addition, when the article is loaded with feces, these can be deposited in the longitudinally oriented pockets positioned laterally outwardly of the absorbent core, thereby leaving the surface of the absorbent member to receive further loading of urine. In the case of relatively thin (or more runny or less viscous) feces, the feces can flow further into the crotch region (eg due to gravity when the wearer is in a standing position). However, with the upward bulge and non-absorbent side seals here, faeces will not cover the absorbent core and disrupt its urine-accepting properties.

In each of the above cases, the backsheet (216) must withstand these loadings and not allow permeation (even if designed to allow vapor transmission) under conditions of normal use.

It will be readily appreciated that these longitudinal side pockets need to be sealed against the wearer's skin, for example by means of elastic means (234) disposed between the backsheet (216) and the topsheet (236).

Within the scope of the present invention, these pockets may also be formed by what is known in the art (for example in EP-A-0,263,720) for baby diapers, so-called "leg-cuffs". In a preferred embodiment of such "leg-closings", the upstanding portions of the secondary cuffs are positioned laterally outward from the fixed base of the same cuff, thereby avoiding the alignment of these cuffs on the surface of the absorbent core, thereby reducing rapid absorption. Or even the ability to repeatedly gush urine.

Particularly preferred embodiments for the present invention include a main body where the pocket can be formed by inwardly folding and securing a backsheet and topsheet material having elastic threads at their longitudinally extending edges (as in EP-A-0,098,512 (Beckestrom)).

Another element of the present invention is the transition from a convex ridge in the crotch region to a concave ridge in the waist when worn.

It is known from static considerations that arc-like structures have a certain structural strength. This structural strength is the point of the present invention in the crotch region where the upward bulge creates such an arcuate structure. As mentioned above, the raised bump should transform into a concave configuration at the waist of the article. A sheet that is folded in one direction in the middle and in the opposite direction at either end can be clearly seen, where the transition area has significant strength and resistance to deformation. Depending on the context, this results in a "pocket" formed during use, or void space between the article and the wearer's body.

Such a pocket has the desired effect because feces can be stored in the void space formed between the omega protuberance and the wearer, i.e. a convex shape in the crotch region towards a concavity in the waist at the upper rear of the article. The transition into the shape creates a "rear poop bag". Such bags have a volume suitable for containing fecal matter, including from about 10 ^cm3 to about 500 ^cm3 or more.

Such a pocket also has the advantage in the design of gender-specific articles that when such a pocket is formed by the front transition zone, a space is formed for the male genitalia.

Such pockets may also be undesirable, for example when intended for light incontinence use and not intended to contain feces, or in the front area of articles intended for use by women, especially when the absorbent core itself is stiff (for example due to high-density fiber structure).

In all cases, it is desirable to have the transition not at an arbitrary position, but at a desired position. Hereafter, a preferred embodiment of the invention uses "hinges" to define the transition from convex to concave.

The relative dimensions between the protrusions, recesses and transition regions will depend on the intended use and the wearer. However, generally the anatomy of the human body requires a minimum lateral extension of the article during use, preferably less than 7 cm, more preferably less than 5 cm, and most preferably even less than 4 cm. In the case of a W-folded core, this dimension is 4 times the thickness of the core, in the case of an Ω-bulged core it is only 2 times the thickness of the core (ignoring the thickness of the material not related to the core). In order to maintain adequate contact at the voiding site, the length of the raised raised area should be at least about 5 cm. The upper limit of this area depends on the intended use and can range from a little more than the stated minimum of 5 cm (e.g. for women, incontinence products) to about 20 cm (for cases that are also expected to contain faeces and require a "rear faecal bag"). "Supplies) change.

Having described how the various elements of the invention interact with each other, a more detailed description of the individual components follows.

A device for forming a permanent Ω (Omega) shape

Currently, many absorbent articles are manufactured in a flat shape, ie, have no particular three-dimensional shape. The person using the article (ie, the user himself or herself, or a caregiver, parent, or the like) can deploy the article in different shapes and through different steps of use.

That is, when the absorbent article is applied to the wearer, it forms a preferred omega shape at least in the crotch region, and normal movement or loading itself during use will cause the omega shape to not be maintained sufficiently significantly and/or for a sufficient period of time . Therefore, in order to maintain the omega shape, the article is provided with means for enhancing the retention of the omega shape during application of the article to the wearer and during use.

Such means for providing an omega-rise may be any means capable of deforming or maintaining the deformation of the absorbent member in the crotch region such that it assumes the above-mentioned shape during application and during use.

The easiest way to achieve an omega shape during application of the article to the wearer is for the manufacturer to fold the article in the correct shape. Thus, it is necessary to fold the article along a longitudinally extending centerline such that the topsheet (ready to face the wearer during use) of the folded portion faces outward, and the backsheet (ready to face outward or toward the wearer's garment orientation) faces Inside, the folded part should include at least the crotch area, especially the loading area. Along with the folding, the person applying the article has a means of easily achieving an omega-shaped bump in application.

In addition, the article may be folded in any manner by the manufacturer, but includes a means for manually creating the omega shape or supporting the omega shape immediately before use by the person applying the article.

Such means may be an elastic member which is stretched (when in a non-omega configuration) and contracts in use to form an omega shape, or it may be a means for securing the respective backsheet portions to each other.

One way to accomplish this is simply to use an adhesive in a traditional manner similar to the adhesives used in women's menstrual products (such as the so-called "panty fastening adhesives" used to secure the product to the wearer's panties). combined device. However, in the present case the aim is to join the backsheet parts together rather than to the garment.

The adhesive can be applied during the manufacturing process and then covered with a release paper known for "panty fastening adhesives". In use, the release paper is removed just prior to joining the corresponding parts of the backsheet together to form the omega shape. It is obvious that in the first case it is easier to pack and transport the article, while in the second case care should be taken not to break/damage its shape during transport.

Additionally, the Ω-shape can be formed during the manufacture of the article. In this case, the adhesive means can be applied to the article while it is in a flat and non-raised state, and then the corresponding backsheet portions are joined together to create the raise.

Another variation of this omega-shaped protuberance utilizes a mechanical connection (such as is commonly referred to as a "mechanical fastening device") such that a first member (formed, for example, of a hook) attached to a portion of a second member Mechanical engagement (for example, by an annular land).

A more preferred variant of securing the respective parts of the backsheet together is not by fixing but by allowing slight movement of the backsheet surfaces relative to each other in the longitudinal direction. This relative movement is of particular benefit during wearer movement such as walking. The Ω-shaped channel is then "distorted" to some degree, without losing its function or its overall Ω-shape.

If the article is intended to be worn by an active person, such as an active, ambulatory adult or toddler, it is particularly useful due to its increased comfort during walking.

Such a structure may be one or more elastic bands or strips (such as indicated at 240 in Figure 2a) having at least one CD-directed contraction force component. They may be attached to the lateral edges of the backsheet (ie, towards the waist) rather than the central portion of the backsheet (ie, the crotch region), thereby drawing the lateral edges together to form an upward ridge or omega ridge. Although the elastic means of the present invention need not necessarily be fixed on the outer edges (i.e. the lower base of the "omega"), care should be taken to shape the article so that only the upper raised portion of the omega is formed by moisture absorption. The core is formed, rather than forming a complete W shape (ie there is no absorbent core in the area of the side flaps 225). This can be achieved by a combination of a core having a certain stiffness and the structural stiffness resulting from the ridges.

Such elastic elements can be placed on the outside or inside of the backsheet, but they should be placed under the absorbent core portion (ie in the direction away from the wearer) because otherwise the chances of getting a U-shaped configuration are too great.

Examples of applications of CD-direction tensile structures are disclosed in European Patent EP-A-0,652,175.

Another preferred solution is to arrange the fastening means at a distance from the backsheet (for example by a pad or stop member) so as to form a hinge between the left and right sides of the transverse longitudinal sides of the article.

In another preferred embodiment, not only the backsheet portion is in intimate contact, but further the entire absorbent structure is joined over its entire thickness.

This allows the shape to be retained even under stressful use conditions.

While the connection should be strong enough to withstand the stress of use and getting wet, the connection should also be flexible enough so as not to increase wearer discomfort.

Other methods of achieving the connections between the backsheets, between the backsheets and additional means for maintaining and sustaining the omega bumps are other known techniques such as the use of glue, fusion bonding and similar methods.

A particularly preferred embodiment in the case of breathable backsheets such as nonwovens is to apply hot air point by point, thereby melting and bonding certain parts of the structure together.

In another embodiment of the invention, the upward convex shape (i.e. Ω-shape) of the absorbent member may be maintained by a separate device which generates an upward force in the crotch region (i.e. towards the the wearer).

In a first embodiment, such a lifting member may be integrally formed in a one-piece article, for example by placing elastic elements on one side of the absorbent member (in use away from the wearer), the elastic The element has a contraction force component in the longitudinal direction of the article. Thus, these components should be located at least in the crotch region and/or load zone, but also in the region of the longitudinal centerline, i.e. not too far from this longitudinal centerline to form an omega hump (if off-centre in the left or right direction This usually occurs when the thread is not smaller than 2.5cm).

In a second embodiment, such lifting means may also be located in a separate part which is not integral or integral with the absorbent core part (ie the absorbent pad). Such means may be a separate underpants (eg mesh underpants) worn over the absorbent article. A particularly preferred pant for this application is described in serially filed patent application Attorney Docket, CM1637Q.

Such suitable panties include an elastic waistband, a front panel with first and second sections, a back panel with first and second sections, a crotch region between them and connecting the front panel with the back panel, and One pair of elasticated leg openings. The first portion of the front panel has a greater resistance to stretch in the transverse direction than the second portion of the front panel. The first portion of the back panel has a greater resistance to stretch in the transverse direction than the second portion of the back panel. The crotch region is provided with a longitudinal stretch control member disposed along the longitudinal centerline of the undergarment. The longitudinal stretch control member limits stretching of the crotch region in the longitudinal direction so that the crotch region conforms to the skin surface of the wearer. A front stretch control is disposed in the front panel and extends from the longitudinal stretch control to the waistband. A rear stretch control member is provided in the back panel and extends from the longitudinal stretch control member to the waistband.

While such suitable panties can be made from materials known in the art to have the required mechanical properties, they are preferably knitted so that they are defined by the combination of knitting and yarns used in the particular components. Mechanical properties with different components are obtained. In a specific preferred embodiment, the longitudinal stretch control part is integrally knitted with the crotch region, the front stretch control part is integrally knitted with the front panel, and the rear stretch control part is integrally knitted with the back panel.

Furthermore, two or more of the above components may be combined in the absorbent article. For example, a pre-folded absorbent pad can be held in place by the preferred stretchable underpants (described above). Alternatively, non-prefolded pads can be provided with an omega-shaped structure by means of an elastic member that is stretched during shipment of the article, and the omega-shaped structure is created just before the pad is applied, and the pad can be made from conventional Stretchable undergarments, such as panties, remain in place without the need for special members to maintain the omega shape, or may be held in place by a modified omega-shaped support undergarment. Furthermore, combinations of body adhesives with pre-folded one-piece articles having MD-directed elastic means for creating a lifting force in the crotch or load area are also suitable.

hinge lines

As already explained above, the "convex-concave" transition should not be positioned randomly, but should occur at a desired position. This can be achieved by providing "twists" in the article, especially in the absorbent core if it is the stiffest part of the article.

Without these additional means, the transition would normally occur somewhere outside the crotch region, either in the front or in the back, where the omega-shape could expand due to the lack of confinement by the wearer's legs , thus allowing a somewhat easier transition that may still lead to detrimental deformation or weakening of the structure.

It is therefore apparent that it would be very beneficial to define the transition from a convex ridge to a concave ridge, which definition can be achieved by forming inflection lines in the absorbent structure.

Such inflection lines can be formed by various methods, such as cutting, or embossing (that is, creating high-density lines throughout the absorbent member, making it easy to bend at the edges of these high-density lines), or low-density lines (for example, Produced by using articles to form areas made of low-weight material while maintaining the same thickness).

The inflection lines facilitating said convex-concave transition must extend from the outer longitudinal edges of the core or elements determining the stiffness of the article in the direction of the longitudinal centerline, ie these inflection lines should be designed to have a transverse orientation. These transition lines may be straight or curved to optimize the specific design of the article and conform to the anatomy of the target group of wearers. And the length of the turning line can be easily selected. Also, several separate lines can be used within each transition zone, or one line can be split into several others. It is preferred that these inflection lines do not extend across the entire width of the absorbent member, as this may result in a detrimental loss of strength or integrity, particularly in particular use.

Such inflection lines can be produced by various methods, such as cutting, or embossing (that is, creating a high density of lines throughout the rigid structure (such as the absorbent core), whereby it is easy to bend at the edges of these high density lines), or low density Lines are formed (for example, by forming regions of low basis weight material in a stiff part and making them less dense than surrounding high basis basis regions).

Design capacity and final storage capacity

In order to be able to compare different end-use conditions or absorbent articles of different sizes, "design energy" has been found to be an appropriate measure.

For example, infants represent a typical user population, but even within this population, on the one hand, from infants (newborns) to toddlers, the amount of urine, the frequency of loading, the composition of the urine vary greatly, and, for example These values also vary among individual toddlers.

Another user group is older children, where some form of inconvenience is still present.

Furthermore, incontinent adults can also use the article within a wide range of loading conditions, ie from so-called light incontinence to severe incontinence.

Accordingly, an article capable of meeting this requirement should have the capacity to absorb the aforementioned volume of urine, which is referred to in further discussion as the "design capacity".

This amount of urine must be absorbed by the materials that ultimately store the bodily fluids, or at least the aqueous portion of these materials, so that only minimal, if any, liquid remains on the surface of the article facing the wearer's skin. The term "ultimate" refers on the one hand to the condition of the absorbent article over a longer number of wears and on the other hand to the absorbent material which has reached its "ultimate capacity" when it is in equilibrium with the surrounding environment. This may be the case of the absorbent article in real use after a relatively long number of wears, or it may be during a test of a single material or material composition. Due to the dynamically asymptotic nature of many of the processes under consideration, one of ordinary skill in the art would consider "final" capacity to be reached when the designed capacity is achieved close enough to the asymptotic endpoint, eg, relative to the measurement accuracy of the device.

Since absorbent articles may comprise materials that are primarily designed to ultimately store liquid, and materials that are primarily designed to perform other functions (such as acquiring and/or distributing liquid) but may also have some ultimate storage capacity, suitable core materials according to the present invention are The description is made without arbitrarily dividing these functions. However, the ultimate storage capacity can be determined for the entire absorbent core, for individual regions of the absorbent core, for the absorbent structure or even for substructures, as well as for the materials used for the aforementioned elements.

When applying the present invention to other absorbent articles for different end uses, one of ordinary skill in the art can readily adopt appropriate designs for other target user groups.

In order to determine or evaluate the ultimate design stored energy of an absorbent article, a number of methods have been proposed.

In describing the present invention, it is assumed that the ultimate storage capacity of the absorbent article is the sum of the ultimate absorbent capacities of the individual elements or materials. For these individual elements, various well-established techniques can be applied, as long as these techniques can be applied continuously during the comparison process. For example, the tea bag centrifuge capacity test developed and established for superabsorbent polymers can be used for superabsorbent polymer materials as well as other materials (see above).

Once the capacity of each material is known, the capacity of the total absorbent article can be found by multiplying these values (ml/g) by the weight of that material used in the absorbent article.

For materials whose dedicated function is not ultimate storage of liquids (such as receiving layers, etc.), the ultimate storage energy is negligible due to the fact that such materials have only very low capacity values compared to dedicated ultimate liquid storage materials, or such Materials are not designed to hold fluids, they release fluids onto other final storage materials.

By these limits, so-called "panliners" exhibit very low final storage capacities of a few milliliters or less. The final storage capacity of sanitary pads is usually about 20 ml, for example 75 ml or about 90 ml for light incontinence products and about 165 ml for medium incontinence products or small babies, toddlers Nappies have a final storage capacity of 300ml or more and severe incontinence products have a final storage capacity of 600ml or more.

Tea bag centrifuge capacity test

The tea bag centrifugal capacity test measures the tea bag centrifugal capacity value, which is an index to measure the liquid retention in the gel material under hydrostatic pressure.

The superabsorbent material was placed in a "tea bag", which was immersed in a 0.9% by weight sodium chloride solution for 20 minutes, then centrifuged for 3 minutes. The ratio of the weight of liquid retained to the initial weight of the dry material is the absorbent capacity of the superabsorbent material.

2 liters of 0.9% by weight sodium chloride in distilled water were poured into a shallow dish measuring 24 cm x 30 cm x 5 cm. The fill height of the liquid should be about 3 cm.

Tea bag sachets measure 6.5 cm x 6.5 cm and are commercially available from Teekanne, Dusseldorf, Germany. The packets can be heat sealed with a standard kitchen plastic bag sealer (eg VACUPACK 2 PLUS manufactured by Krups, Germany).

Open the tea bag by carefully partially cutting it open, and weigh it. A sample of approximately 0.200 grams (+/- 0.005 grams) of superabsorbent material is placed in a tea bag. The tea bag is then sealed with a heat sealer. This is called a sample tea bag.

Seal an empty tea bag again and use it as a blank bag.

Each bag was held level and the sample tea bags were shaken to more evenly distribute the superabsorbent material throughout the bag. The sample tea bags and blank tea bags were then placed on the surface of the saline solution and pressed into the solution with a spatula allowing them to be fully submerged for 5 minutes (the tea bags will initially float to the surface of the saline solution, but then will be completely wet). Start timing immediately.

After steeping for 20 minutes, the sample tea bags and blank tea bags were removed from the saline solution and placed in a Bauknecht WS130, Bosch 772NZK096 or similar centrifuge (230mm diameter) so that each pouch was centrifuged. The outer wall of the machine drum. Close the lid of the centrifuge, start the centrifuge, and quickly increase the speed to 1400 rpm. When the speed of the centrifuge stabilizes at 1400 rpm, start the timer. After 3 minutes, the centrifuge was stopped.

Take out the sample tea bag and the blank tea bag and weigh them respectively.

Calculate the tea bag centrifuge capacity (TCC) of a sample of hygroscopic material as follows:

TCC = [(weight of sample tea bag after centrifugation) - (weight of blank tea bag after centrifugation) - (weight of dry absorbent material)] ÷ (weight of dry absorbent material).

Claims (10)

1. disposable absorbent diaper that is used to receive urine and feces comprises:

Top flat (29), egative film (16) and be positioned between the two absorbent article core (10);

Wherein, described core (10) comprises front waist region and back waist region, and these two zones all are that concave shape is with suitable with wearer's health;

It is characterized in that described core (10) comprises the urine loading zone, this district has upwards the raised bumps shape towards the wearer;

Wherein, described raised bumps be by at least in described urine loading zone along folding in advance this diaper of the longitudinal centre line of diaper, make at least some parts of egative film (16) of covering absorbent core (10) be in direct contact with one another to realize;

And described core also comprises the free vertically limit (19,20) of containing elastic component (21,22), and the vertical limit of described freedom forms by described egative film is inwardly folding;

Described diaper also comprises between front waist region and the urine loading zone or the one or more transition regions between back waist region and the urine loading zone;

And the described transition region of absorbent article core (10) forms at least one bag, and described bag is positioned at the position of vertically departing from backward.

2. moisture absorption diaper according to claim 1, the described raised bumps shape that it is characterized in that the urine loading zone is to form by the binding agent that is applied to from the outside on the egative film (16).

3. moisture absorption diaper according to claim 1, the described raised bumps shape that it is characterized in that the urine loading zone forms by mechanical meshing device, the location of turning up the soil, the centrage lateral separation of at least a portion of described device and the longitudinal extension of described diaper.

4. moisture absorption diaper according to claim 1, but it is characterized in that the described raised bumps shape of urine loading zone realizes by the elastic telescopic parts, and described parts have the force component on the direction of the machine direction of lying across at least.

5. moisture absorption diaper according to claim 3, the described device that it is characterized in that being used to obtaining the described raised bumps shape of urine loading zone is fixed on the transverse sides of described core (10,228), and is fixing in central authorities.

6. moisture absorption diaper according to claim 5, it is characterized in that described diaper have length and width dimensions and with all vertical z direction of above-mentioned two sizes,

But the described device that wherein is used for obtaining in the raised bumps shape of urine loading zone is the parts (234) of elastic telescopic, and it has the force component of machine direction at least, in use applies a force component towards the z direction of wearer's orientation at least.

7. according to each described moisture absorption diaper in the claim 1 to 6, it is characterized in that:

Described diaper also comprises and is used for described diaper is fixed on fixture on the wearer's body.

8. moisture absorption diaper according to claim 7 is characterized in that described fixture comprises belt and overlap joint zone, ground bonded to each other, its forward and backward lumbar region with diaper or mechanically be fixed together.

9. moisture absorption diaper according to claim 7 is characterized in that described fixture also comprises the elastic component that is used for diaper is remained on the position.

10. moisture absorption diaper according to claim 1, the design capacity that it is characterized in that described absorbent article core (10) is greater than 70 milliliters of urines.

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