EP2056766A1

EP2056766A1 - Dehydratable hygiene article

Info

Publication number: EP2056766A1
Application number: EP07786457A
Authority: EP
Inventors: Harald Schmidt
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-07-31
Filing date: 2007-07-31
Publication date: 2009-05-13
Also published as: US20090326497A1; DE102006035945A1; DE102006035945B4; US8710292B2; WO2008014972A1

Abstract

The present invention concerns dehydratable hygiene articles comprising: i) a lower layer impermeable to aqueous fluids, ii) an upper layer permeable to aqueous fluids, iii) an absorbent core for aqueous fluids disposed between the lower and upper layers, and also iv) a trigger system comprising a superabsorbent material (a) capable of absorbing aqueous fluids by forming a hydrogel, wherein after the trigger system has been triggered, the superabsorbent material (a), when present as hydrogel, is capable of releasing at least a portion of the absorbed, aqueous fluid, wherein the hygiene article comprises not more than 50% by weight of a further superabsorbent material (b), based on the total weight of superabsorbent material (a) and superabsorbent material (b), capable, after the trigger system (iv) has been triggered, of absorbing the at least partially released aqueous fluid, if appropriate after a further trigger system other than trigger system (iv) has been triggered, by at least partially forming a hydrogel, or the hygiene article has a compressibility factor, determined in accordance with the test method described herein, of at least 1.1. The invention also concerns a process for dehydrating a hygiene article, a device for dehydrating a dehydratable hygiene article comprising a superabsorbent material, the use of a device for dehydrating hygiene articles and also kits.

Description

Dehydrated hygiene article

The invention relates to dehydratable hygiene articles, a method for dehydrating a hygiene article, a device for dehydrating a dehydratable hygiene article containing a water-absorbing material, the use of a device for dehydrating hygiene articles and kits.

Sanitary articles such as diapers or sanitary napkins contain so-called superabsorbents as liquid-absorbent materials. These superabsorbents are water-insoluble, crosslinked polymers which are capable of absorbing, and retaining under a certain pressure, large quantities of aqueous liquids, in particular body fluids, preferably urine or blood, while swelling and forming hydrogels.

As a rule, these hygiene articles are disposable products. However, due to the absorption of body fluids by the superabsorbents, these hygiene articles swell up considerably, resulting in a significant increase in the volume of the hygiene article. However, this increase in volume of the hygiene article is disadvantageous, since, in particular in households with several hygiene article carriers, for example in families with several diaper-bearing small children, the volume fraction of the diapers in the total residual waste is very large.

The literature describes various approaches to solving the problems associated with the large volume of waste produced by used sanitary articles.

For example, GB-A-2284820 describes rinsable products which have a wet strength which is sufficient for their intended use, in particular in the case of prolonged or extended use, in the presence of body fluid. and at temperatures above 25 ° C, which, however, decay and disperse in the presence of ordinary tap water. However, the disadvantage of the method described in this prior art of reducing the volume of waste caused by swollen articles of hygiene is that the individual components of the hygiene article can not be disposed of and thus recycled, but instead dissolved in the tap water and dissolved therein Condition can be disposed of through the sewers. However, this type of waste disposal is questionable, since the individual components of the hygiene articles can adversely affect the quality of the groundwater.

DE 296 07480 U1 discloses a diaper garbage press having a cavity, at least two planar elements which are designed to be movable relative to one another, the two planar elements being connected to one another by a connecting element and forming the cavity one above the other, and wherein an opening is formed in a planar element. Through this opening a garbage bag filled with disposable diapers is placed. By compressing the two flat elements, a large part of the air contained in the diaper waste is expelled. The disadvantage of the method described in this prior art is that a really efficient reduction of the waste volume can not be achieved.

The present invention has for its object to overcome the disadvantages resulting from the prior art.

In particular, it is an object of the present invention to provide sanitary articles which, after being used, result in lower waste volume compared to conventional sanitary articles.

It was also the object of the present invention to provide hygiene articles that are simple and relatively small waste volume environmentally friendly disposal of the residual waste. The disposal of the hygiene articles should not lead to a pollution of the groundwater.

A further object of the present invention is to provide a device by means of which the volume of used hygiene articles can be reduced as efficiently as possible in comparison with the devices known from the prior art.

A contribution to the solution of the above-mentioned objects is made by a dehydrated hygiene article comprising:

i) a lower layer impermeable to aqueous liquids, ii) an upper layer permeable to aqueous liquids, iii) an aqueous layer located between the lower and the upper layer

(Ii) a triggering system comprising a superabsorbent material (a) capable of absorbing aqueous fluids to form a hydrogel, wherein after triggering of the triggering system, the superabsorbent material (a), when used as a Hydrogel is present, at least a portion of the absorbed, aqueous liquid can be released,

wherein the hygiene article at most 50 wt .-%, preferably at most 25 wt .-%, more preferably at most 10 wt .-%, even more preferably at most 5 wt .-%, more preferably at most 1 wt .-% of a further superabsorbent material (b), based in each case on the total weight of superabsorbent material (a) and superabsorbent material (b), but most preferably does not comprise any further superabsorbent material (b) which would be capable, after triggering the trigger system (iv ) the at least partially released aqueous liquid, optionally after release another, independent of the trigger system (iv) trigger system, at least partially to absorb a hydrogel to absorb.

According to a particular embodiment of this hygienic article according to the invention this is by a determined according to the test method described herein compressibility factor of at least 1.1, preferably at least 1.5, more preferably at least 2, more preferably at least 3, even more preferably at least 4 and most preferably at least 5 marked.

A contribution to the solution of the abovementioned objects is also provided by a de-hydratable hygiene article comprising:

Fluid-absorbent core; and iv) a trigger system comprising a superabsorbent material (a) capable of absorbing aqueous fluids to form a hydrogel, wherein after triggering of the triggering system, the superabsorbent material (a), when used as Hydrogel is present, at least a portion of the absorbed, aqueous liquid can be released,

wherein the hygiene article has a compressibility factor of at least 1.1, preferably at least 1.5, more preferably at least 2, more preferably at least 3, even more preferably at least 4, and most preferably at least 5 as determined in accordance with the test method described herein.

Diapers, sanitary napkins, panty liners, bed liners or incontinence pads are preferred as hygiene articles, diapers and sanitary napkins being particularly preferred. and diapers are the most preferred sanitary products. The term "diaper" refers generally to an absorbent clothing ^¬ tee that is worn by infants for liquid absorption as well as people with incontinence problems.

The term "superabsorbent" for a particular material indicates that this material is capable of at least 25 times, preferably at least 30 times, more preferably at least that upon contact with 0.9% by weight aqueous NaCl solution 40 times, and most preferably 50 to 60 times the own weight of this aqueous NaCl solution according to the test method according to ERT 441.2-02 retain.

Hygiene articles with the components i) to iv) are basically known from US 6,696,618. However, the hygiene articles described in US Pat. No. 6,696,618 always contain, in addition to the dehydratable, superabsorbent material, further superabsorbent material which is capable of absorbing the liquids released on dehydration, so that overall a hygiene article is present which exhibits the most advantageous leakage behavior. Dehydration of the hygiene articles, which would be associated with a reduction in volume, however, is not possible with the hygiene articles described in US Pat. No. 6,696,618.

In the following, preferred embodiments of a hygiene article according to the invention are explained in more detail using the example of a diaper according to the invention. In view of the nature of the materials used, however, these statements also apply to other hygiene articles, such as sanitary napkins.

As impermeable lower layer (i) for aqueous liquids, preference is given to using materials such as those described in DE 695 21 888 T2 as "liquid-impermeable outer layer." The disclosure of DE 695 21 888 T2 with regard to the individual components of a hygiene article, in particular a diaper, is hereby incorporated by reference and forms part of the disclosure of the present invention. Preferably, the impermeable lower layer (i) is made of a flexible, woven or non-woven material. According to a particularly preferred embodiment of the dehydratable diaper according to the invention, the impermeable lower layer (i) is a polyethylene film having a thickness in a range of 0.005 to 0.1 mm, particularly preferably in a range of 0.01 to 0.05 mm. Further, the impermeable lower layer (i) may be embossed or provided with a felt to give the diaper the appearance of a garment. According to a particular embodiment of the dehydratable diaper according to the invention, the impermeable lower layer (i) is a breathable material which is impermeable to aqueous liquids but not to water vapor. In this connection, it is preferred that the hygiene article has, as a further component, a hydrophobic barrier material located between the impermeable lower layer (i) and the absorbent core (iii), as described in DE 697 19 217 T2, which is also hereby incorporated by reference Reference is made and the disclosure of which regarding the structural design of a hygiene article forms part of the disclosure of the present invention. Preferred water-vapor-permeable layers impermeable to water in liquid form, as well as preferred hydrophobic barrier materials, are those materials which, in DE 697 19217 T2, are preferred materials for the "breathable, liquid-impermeable, outer cover" or for the "hydrophobic barrier" to be named.

The upper layer (ii) which is permeable to aqueous liquids are preferably layers which are referred to as "top layer" in DE 695 21 888 T2 Preferably, the upper layer (ii) permeable to aqueous liquids is woven or non-woven materials, polymeric materials such as apertured thermoplastic films, porous foams, reticulated foams, reticulated thermoplastic films, or the like natural fibers, such as pulp fibers or cotton fibers, of synthetic fibers, such as polyether fibers, polypropylene fibers or polyethylene fibers, or a blend of natural or synthetic fibers.

As the aqueous liquid absorbent core (iii) disposed between the lower and upper layers (i) and (ii), it is preferable to use absorbent cores comprising a superabsorbent material and a preferably non-superabsorbent fibrous material as a substrate wherein the superabsorbent material in the absorbent core is preferably the superabsorbent material (a) which is part of the trigger system (iv). By "non-superabsorbent" is preferably understood a material which is able to retain less than 10 g / g, more preferably less than 5 g / g, of 0.9% strength by weight NaCl solution according to the test method according to ERT 441.2-02 ,

Preferred superabsorbent materials according to the invention are preferably synthetic polymer fibers, polymer foams or polymer particles, with fibers and particles being preferred and particles being particularly preferred.

Superabsorbent polymer fibers preferred according to the invention are dimensioned such that they can be incorporated into or as yarns for textiles and also directly into textiles. It is preferred in the invention that the superabsorbent polymer fibers have a length in the range of 1 to 500 mm, preferably 2 to 500 mm and more preferably 5 to 100 mm and a diameter in the range of 1 to 200 denier, preferably 3 to 100 denier, and more preferably 5 to 60 Denier own.

Superabsorbent polymer particles which are particularly preferred according to the invention are dimensioned such that they have an average particle size in accordance with ERT 420.2-02

(ERT = Edana Recommended Test Method) in the range of 10 to 3000 μm, preferably 20 to 2000 microns and more preferably 150 to 850 microns. Furthermore, it is preferred according to the invention for the superabsorbent polymer particles to comprise at least 25% by weight, preferably at least 50% by weight and most preferably at least 75% by weight, of particles having a particle size in the range from 300 to 600 μm based.

Furthermore, it is preferred that the superabsorbent material in the absorbent core (iii) has at least one, preferably all of the following properties: (A) maximum uptake of 0.9% by weight of NaCl solution according to ERT 440.2-02 in one range from at least 10 to 1000 g / g, preferably from 15 to 500 g / g and more preferably from 40 to 150 g / g (in the case of particles determined for the total particle fraction),

(B) the extractable with 0.9 wt .-% aqueous NaCl solution according to ERT 470.2-02 fraction is less than 30 wt .-%, preferably less than

20% by weight and more preferably less than 15% by weight,

(C) the bulk density according to ERT 460.2-02 is in the range of 300 to 1000 g / l, preferably 310 to 800 g / l and particularly preferably 320 to (D) the retention capacity according to ERT 441.2-02 ranges from 10 to

100 g / g, preferably 15 to 80 g / g and particularly preferably 20 to 60 g / g (im

Trap of particles determined for the total particle fraction),

(E) the AAP value according to ERT 442.2-02 at a pressure of 0.3 psi is in

Range of 10 to 60 g / g, preferably 15 to 50 g / g and particularly preferably 20 to 45 g / g (in the case of particles determined for the entire particle fraction).

Fibrous materials which may be included as a substrate in the absorbent core (iii) include naturally occurring fibers (modified or unmodified) as well as synthetic fibers. Examples of suitable unmodified and modified naturally occurring fibers include cotton, esparto grass, Bagasse, kemp, flax, silk, wool, wood pulp, chemically modified wood pulp, jute, rayon, ethyl cellulose and cellulose acetate, Suitable synthetic fibers can be made from polyvinyl chloride, polyvinyl fluoride, polytetrafluoroethylene, polyvinyl lyvinylidenchlorid, polyacrylate such as Orion ^®, polyvinyl acetate, polyethylvinyl acetate, non-soluble or soluble polyvinyl alcohol, polyolefins such as polyethylene (e.g., PULPEX ^®) and polypropylene, polyamides such as nylon, Polyes- tern like can be prepared as DACRON ^® or Kodel ^®, polyurethanes, polystyrenes and the like. The fibers used may comprise only naturally occurring fibers, only synthetic fibers or any compatible combination of naturally occurring and synthetic fibers.

The fibers of the fibrous material may be hydrophilic or hydrophobic, or they may consist of a combination of hydrophilic and hydrophobic fibers. As used herein, the term "hydrophilic" describes fibers or surfaces of fibers that are wettable by aqueous fluids (eg, aqueous body fluids) deposited on these fibers. Hydrophilicity and wettability are typically defined in terms of the contact angle and surface tension of the liquids and solids involved. This is discussed in detail in a publication by the American Chemical Society titled "Contact Angle, Wettability and Adhesion," edited by Robert F. Gould (copyright 1964). A fiber or the surface of a fiber is wetted by a liquid (that is, it is hydrophilic) if either the contact angle between the liquid and the fiber or its surface is less than 90 °, or if the liquid tends to spontaneously diffuse above the fiber Distribute surface, where both conditions are usually present simultaneously. Conversely, a fiber or the surface of a fiber is considered to be hydrophobic if the contact angle is greater than 90 ° and the fluid does not spontaneously spread on the surface of the fiber.

Fibers preferred according to the invention are hydrophilic fibers. Suitable hydrophilic Ie fibers include cellulose fibers, modified cellulose fibers, rayon, Polyes ^¬ terfasern such as polyethylene terephthalate (DACRON ^®, for example), hydrophilic nylon (HYDROFIL ^®) and the like. Suitable hydrophilic fibers may also be obtained by hydrophilizing hydrophobic fibers, such as surfactant-treated or silica-treated thermoplastic fibers derived, for example, from polyolefins, such as polyethylene or polypropylene, polyacrylics, polyamides, polystyrenes, polyurethanes and the like. For reasons of availability and cost, cellulose fibers, in particular pulp fibers, are preferred as fibrous material in the absorbent core (iii). Further preferred hydrophilic fibers for use in the present invention are chemically stiffened cellulosic fibers. The term "chemically-entangled cellulosic fibers" refers to cellulosic fibers that are stiffened by chemical means to increase the stiffness of the fibers under both dry and aqueous conditions, Such agents may include the addition of a chemical stiffening agent covering, for example, the fibers Such means may also include stiffening the fibers by altering the chemical structure, for example, by crosslinking polymer chains. Polymer stiffening agents that can coat or impregnate the cellulosic fibers include: cationic starches nitrogen-containing groups (e.g., amino groups) such as those available from National Starch and Chemical Corp., Bridgewater, NJ, USA, latexes, wet strength resins such as polyamide-epichlorohydrin resin (e.g., Kymene ^®) 557H, Hercules, Inc., Wilmington, Delaware , USA), polyacrylamide resins, such as si e are described for example in US 3,556,932, com- mercially available polyacrylamides such as Parez ^® 631 NZ American Cyanamid Co., Stanford, CT, USA, urea formaldehydes and melamine-formaldehyde resins. Fibers stiffened by crosslink bonds in individual forms (i.e., the individual stiffened fibers as well as the methods for their preparation) are described, for example, in US 3,224,926, US 3,440,135, US 3,932,209 and US 4,035,147. Preferred crosslinking agents are glutaraldehyde, glyoxal, formaldehyde, glyoxylic acid, oxydisuccinic acid and citric acid. re. The stiffened cellulosic fibers obtained by crosslinking or coating, impregnation or crosslinking may be twisted or curled, preferably the fibers are twisted and additionally crimped.

Furthermore, all the fibers can be used as the fiber material, which in DE 695 21 888 T2 on page 59ff. as thermoplastic fibers. According to a particular embodiment of the inventive dehydrable hygiene articles, the absorbent core comprises, in addition to the superabsorbent material, cellulose fibers and bicomponent fibers, in particular so-called sheath-core fibers of polyethylene and polypropylene, polyethylvinyl acetate and polypropylene, polyethylene and polyester, polypropylene and polyester or copolyesters and Polyester. Particularly preferred two-component fibers are in turn those two-component fibers which are mentioned in DE 695 21 888 T2 as two-component fibers.

In a particular embodiment of the absorbent core (iii), this comprises, in addition to the substrate and the superabsorbent material, further pulverulent substances, for example odor-binding substances, such as cyclodextrins, zeolites, inorganic or organic salts and similar materials. Furthermore, it is preferable in the invention that the absorbent core (iii) has at least a range in which the amount of superabsorbent material is in a range of 10 to 100% by weight, preferably in a range of 20 to 95% by weight and particularly preferably in a range from 50 to 90% by weight, based on the range, this range preferably having a size of at least 0.001 mm ³ , more preferably of at least 0.01 mm ³ , more preferably of at least 0, 1 mm ³ and most preferably at least 0.3 mm.

The structure and the other components optionally present in the absorbent core (iii) correspond to the structure or components corresponding to those described in DE 695 21 888 T2 in connection with The disclosure of DE 695 21 888 T2 regarding the structure of the "absorbent elements" is hereby incorporated by reference and forms part of the disclosure of the present invention.

The fibrous or particulate superabsorbent materials may be homogeneously distributed in the fibrous materials, may be layered between the fibrous material, or the concentration of the superabsorbent materials may have a gradient within the fibrous material.

The absorbent core (iii) can be synthesized by conventional methods known to those skilled in the art, such as drum forming by means of forming wheels, bags and product molds, and appropriately adjusted metering devices for the raw materials. In addition, modern, established methods such as the so-called airlaid method (eg EP-AO 850 615, US 4,640,810) with all forms of metering, deposition of the fibers and solidification such as hydrogen bonding (eg DE-A-197 50 890), thermobonding, latex bonding (eg EP-AO 850 615) and hybrid bonding, the so-called wet-laid process (eg WO-A-99/49905), carding, meltblown, spunblown processes and the like Processes for the production of absorbent non-wovens (as defined by EDANA, Brussels) also in combinations of these processes with and among common methods for producing the absorbent core (iii). As further processes, the production of laminates in the broadest sense as well as extruded and coextruded, wet and dry and subsequently solidified structures come into question.

In a further embodiment of the absorbent core (iii), this comprises, in addition to the substrate (= fibrous material) and the superabsorbent material incorporated into the substrate, which together serve as a storage layer for the body fluids, a receiving layer (v), preferably for rapid absorption and distribution of the liquid in the absorbent core (iii). There- at the Aufhahmeschicht (v) can be directly over the storage layer angeord ^¬ net, but it is also possible that the Aufhahmeschicht (v) by a preferably liquid stable intermediate layer (vi) is separated from the storage layer. This intermediate layer (vi) then serves primarily as a support substrate for the Aufhahmeschicht (v) and the storage layer. Preferred materials for this intermediate layer (vi) are polyester spunbonded nonwovens, or nonwovens made of polypropylene, polyethylene or nylon. In one embodiment of the absorbent core (iii), the receiving layer (v) is free of the superabsorbent material. The receptacle layer (v) may be any suitable size and need not extend the entire length or width of the storage layer. The Aufhahmeschicht (v) may be formed, for example in the form of a strip or stain. The entire receiving layer (v) is preferably hydrophilic, but it may also have hydrophobic components. The receiving layer (v) may comprise a woven material, a nonwoven material or another suitable type of material. Preferably, the receiving layer (v) is based on hydrophobic polyethylene terephthalate (PET) fibers, chemically stiffened cellulosic fibers, or blends of these fibers. Other suitable materials are polypropylene, polyethylene, nylon or biological fibers. When the containment layer (v) comprises a nonwoven material, it can be made by a variety of different methods. These include wet, air-laid, melt-applied, spunbond, carding (which includes thermal bonding, solvent bonding, or melt spinning). The latter processes (formation as spunbonding and carding) are preferred when it is desired to align the fibers in the receiving layer (v), since in such processes it is easier to orient the fibers in a single direction. A particularly preferred material for the receiving layer (v) is a PET spunbonded fabric.

Further, the absorbent core (iii) is preferably particularly by a basis weight of at least 0.03 g / cm ² , preferably at least 0.06 g / cm ² preferably in the range of 0.03 to 0.12 g / cm ² and more preferably in the range of 0.06 to 0.12 g / cm ² , wherein the absorbent core (iii) further has a thickness of at most about 20 mm, preferably at most about 15 mm and moreover, preferably at most about 10 mm. The surface of the absorbent core (iii) is preferably at most about 2,500 cm ² , more preferably at most about 1,000 cm ^2, and further preferably at most about 500 cm ² .

According to a preferred embodiment of the dehydratable diaper according to the invention, the lower layer (i) impermeable to aqueous liquids, the upper layer (ii) permeable to aqueous liquids and the absorbent core (iii) are arranged as described in EP-A-802 776 in FIG. 1 for the liquid-impermeable cover sheet described there, the liquid-permeable cover sheet and the absorbent core. In this case, the upper layer (ii), which comes into contact with the skin of the diaper wearer, is connected to the lower layer (i) along the circumference of the lower layer (i). The absorbent core (iii), which is also preferably connected to the lower layer (i), is disposed between the layers (i) and (ii). This arrangement of the components results in a diaper underside which faces away from the thread carrier, a diaper top which comes into contact with the skin of the diaper carrier when the diaper is worn, and due to the finite thickness of the upper layer (ii) and the lower layer (i) of the absorbent core (iii) enclosed, a lateral edge extending in the longitudinal direction of the absorbent core (iii). The height of this lateral edge increases as aqueous liquids penetrate through the permeable top layer (ii) into the absorbent core (iii) causing it to swell.

The dehydratable hygiene articles according to the invention comprise, as further component, a triggering system (iv) comprising a superabsorbent material (a) which is capable of absorbing aqueous fluids to form a hydrogel, whereby after triggering of the triggering system the superabsorbent material is material (a), if present as a hydrogel, at least a portion of the absorbed, aqueous liquid can be released. It is preferred that within 120 minutes, preferably within 60 minutes and more preferably within 30 minutes after triggering the trigger system, the "Centrifuge Retention Capacity" determined in accordance with ERT 441.2-02 (in the case of a particulate superabsorbent material (a) determined for the total particle fraction) of the superabsorbent material is reduced by at least 20%, preferably by at least 40%, and most preferably by at least 60%.

For the purposes of the present invention, a "trigger system" is preferably understood to mean a system which can fundamentally exist in two different states, wherein the system acts on one of the at least two different states in the other of the at least ones by a targeted action acting on the trigger system two different states can be transferred.

In the context of the triggering system, it is further preferred that within 30 minutes, preferably within 60 minutes and more preferably within 120 minutes after triggering of the trigger system, the content of the superabsorbent material determined in accordance with ERT 470.2-02 (a ) increases by less than 50%, preferably less than 35%, more preferably by less than 20% by weight, and most preferably by less than 10%.

According to a first particular embodiment of the dehydrable hygiene articles according to the invention, the trigger system (iv) comprises an anionic superabsorbent material (a) whose absorption properties are pH-dependent and an acidic material which is spatially separated from the superabsorbent material (a) (c ), whereby the triggering of the trigger system by allowing the acidic material (c) to contact the hydrogel.

As the anionic superabsorbent material, preferred are polymers which

(αl) 20-99.999 wt .-%, preferably 55 to 98.99 wt .-% and particularly preferably 70 to 98.79 wt .-% of polymerized, ethylenically unsaturated, acid-containing monomers or their salts or polymerized, ethylenically unsaturated , a protonated or quaternized nitrogen-containing monomer, or mixtures thereof, wherein at least ethylenically unsaturated, acid group-containing monomers, preferably acrylic acid-containing mixtures are particularly preferred,

(α2) 0-80% by weight, preferably 0-44.99% by weight and particularly preferably 0.1-44.89% by weight of polymerized, monoethylenically unsaturated monomers copolymerizable with (α1),

(α3) 0.001-5 wt.%, preferably 0.01-3 wt.% and particularly preferably 0.01-0.5 wt.% of one or more crosslinkers,

(α4) 0-30% by weight, preferably 0-5% by weight and more preferably 0.1-

5 wt .-% of a water-soluble polymer, (α5) 0 - 20 wt .-%, preferably 2.5 - 15 wt .-% and particularly preferably 3-6 wt .-% water, and

(α.6) 0 to 20 wt .-%, preferably 0 to 10 wt .-% and particularly preferably 0.1 to 8 wt .-% of one or more auxiliaries, wherein the sum of the amounts by weight (αl) to (α6 ) 100 wt .-% is.

With regard to the preferred components (α1) to (α6) and the manner of preparation of these polymers, reference is made to the WO-A-

2004/037903, the disclosure of which is hereby incorporated by reference.

Anionic, superabsorbent materials preferred according to the invention are crosslinked polymers which contain at least 50% by weight, preferably at least 70 wt .-% and more preferably at least 90 wt .-% based on carboxylate-containing monomers. It is further preferred according to the invention that the carboxylate-containing monomer to at least 50 wt .-%, preferably at least 70 wt .-% of acrylic acid, preferably at least 20 mol%, more preferably at least 50 mol% and beyond is preferably neutralized in a range of 60 to 85 mol%.

It is particularly preferred according to the invention that in the case of this first particular embodiment of the dehydratable hygiene article according to the invention, the anionic superabsorbent material (a) is a crosslinked polyacrylate in particulate form which is obtained by polymerization of an optionally already partially neutralized acrylic acid in the presence of one of the in WO-A- 2004/037903 in aqueous solution containing the acrylic acid in an amount in a range of 5 to 80 wt .-%, preferably 10 to 70 wt .-% and particularly preferably 20 to 50 wt .-%, based on the weight of the aqueous solution, and then crushing the obtained hydrogel, drying the crushed hydrogel to a water content in a range of 1 to 50% by weight, preferably 2.5 to 40% by weight, and particularly preferably 5 to 30% by weight. -%, and optionally further grinding of the dried hydrogel was obtained.

In addition to this anionic superabsorbent material (a), the triggering system in this first particular embodiment of the hygiene article of the invention comprises an acidic material (c) spatially separated from the superabsorbent material (a). In this case, "spatially separated present" means that the acidic material (c) is arranged in the dehydratable hygiene article such that it is in contact with the anionic superabsorbent material only after the triggering system has been triggered, for example by a defined mechanical action on the hygiene article (a). can occur. The acidic material (c) may be any organic or inorganic acid known to those skilled in the art. Preferably, the acidic material (c) used is an organic, preferably pulverulent material, for example a material selected from the group comprising lactic acid, glutaric acid, aspartic acid, malonic acid, adipic acid, amino acids, citric acid, benzoic acid, fumaric acid, maleic acid or oxalic acid. Instead of or in addition to these organic, preferably powdery, acidic materials, it is also possible to use liquid acidic materials such as, for example, dilute formic acid, dilute acetic acid or dilute hydrochloric acid.

According to a particularly preferred embodiment of this first variant of the hygiene article according to the invention, the superabsorbent material (a) is a cross-linked, partially neutralized polyacrylate and the acidic material (c) is citric acid.

The spatial separation of the anionic superabsorbent material (a) and the acidic material (c) in the hygiene article according to the invention is preferably achieved in that the anionic superabsorbent material (a) as superabsorbent material in the absorbent core (iii) in the manner described above is incorporated while the acidic material (c) is housed spatially separated from the absorbent core (iii), wherein the spatial separation must be such that the acidic material (c) especially with a contact of the diaper with body fluids not readily with the anionic superabsorbent material (a) can come into contact. For this purpose, the acidic material (c) is preferably incorporated into a capsule and one or more of these capsules, for example, in the absorbent core (iii) or in the Aufhahmeschicht (v), if the hygiene article is a diaper, which is such Aufhahmeschicht has introduced. Furthermore, the capsule may, for example, be arranged on the side of the lower layer (i) facing the absorbent core (iii). In principle, the capsule can be arranged in every imaginable area of the hygiene article as long as it is ensured that is that the absorption properties of the hygiene article is not appreciably affected by the presence of ^¬ the capsule or capsules and that after destruction of the capsule, the acidic material (c) with the anionic superabsorbent material (a) can come into contact.

The capsule is preferably a capsule which

al) by mechanical action, a2) by thermal action, a3) by electromagnetic radiation, or a4) by chemical changes,

can be influenced so in their integrity that the acidic material (c) can be released from the capsule, which release also delayed after the onset of the effects according to al) or a2) or after the start of e- lektromagnetische irradiation or a chemical changes according to a3) or a4). The capsule can be, for example, spherical particles of a thermoplastic material, plastic capsules that are easily breakable, capsules of a material which is sensitive to electromagnetic radiation, in particular sensitive to UV radiation, or else wafer-thin glass bodies , In addition, the capsules can not only have a spherical shape, but also be tubular, for example. Furthermore, it would be conceivable that the acidic material (c) is introduced, for example, in a closed at one end plastic tube over which a second, also closed one end plastic tube is slipped. The triggering of the triggering system in this case could take place in that, when the tube filled with the acidic material (c) is arranged longitudinally to the absorbent core (iii) in a dehydratable diaper according to the invention, the diaper is stretched in the longitudinal direction of the absorbent core (FIG. iii) is pulled apart, that the two superimposed plastic hoses in opposite Direction so that the acidic material (c) can now contact the anionic superabsorbent material (a) in the absorbent core (iii).

In addition to the encapsulation of the acidic material (c), it may also be present through a single membrane separate from the anionic superabsorbent material (a) in which, for example, the lower layer (i) has depressions into which the acidic material (c) is introduced. These depressions are then sealed with a material which, like the above-described capsule material, can be easily destroyed by mechanical, thermal or electromagnetic influences.

The amount of acidic material (c) relative to the amount of anionic superabsorbent material (a) is preferably selected so that after the triggering of the trigger system (iv) the degree of neutralization of the superabsorbent material (a) is at least 10 mol%, preferably at least 20 mole%, more preferably at least 30 mole%, more preferably at least 40 mole%, and most preferably at least 50 mole%. Thus, if a partially neutralized, crosslinked polyacrylate having a degree of neutralization of 70 mol% is used as the superabsorbent material (a), it is preferred to provide an amount of acidic material (c) such that the degree of neutralization after triggering of the trigger system (iv) is reduced to at most 60% by mole, preferably at most 50% by mole, even more preferably at most 40% by mole, more preferably at most 30% by mole, and most preferably at most 20% by mole. In the case of an anionic superabsorbent material (a), a degree of neutralization of X mol% means that X mol% of the acid groups present in the superabsorbent material (a) are present in the form of the corresponding base.

According to a second particular embodiment of the inventive degradable hygiene articles, the triggering system (iv) comprises a cationic suicide perabsorbierendes material (a) whose absorption properties depend on the pH, as well as a by the superabsorbent material (a) ge spatially ^¬ separates vorliegendes basic material (d), wherein initiation of the Triggersys ^¬ tems takes place in that there the basic material (d) is allowed to contact the hydrogel.

As the cationic superabsorbent material (a), crosslinked polymers based on ethylenically unsaturated quaternary nitrogen-containing monomers are preferable. Preferred monomers in this context are dialkylammoniumalkyl (meth) acrylates in quaternized form, for example trimethylammoniumethyl (meth) acrylate methosulfate or dimethylethylammonium methyl (meth) acrylate ethosulfate and (meth) acrylamidoalkyldialkylamines in quaternized form, for example (meth) acrylamidopropyltrimethylammonium chloride, Trimethylammoniumethyl (meth) acrylate chloride or (meth) acrylamidopropyltrimethylammonium sulfate is preferred. Crosslinked polyamines, polyvinylamines, polyallylamines, polyethyleneimines or polydiallyldimethylammonium chloride, or natural cationic polymers, such as partially deacetylated chitin, chitosan and chitosan salts, are furthermore preferred as cationic water-absorbing materials.

As the basic material (d), any organic or inorganic base known to those skilled in the art can be used. The basic material (d) used is preferably an inorganic, powdery material, for example a material selected from the group comprising sodium carbonate, sodium bicarbonate, ammonium carbonate or sodium hydroxide. Instead of or in addition to these inorganic, powdery basic materials, it is also possible to use aqueous, basic solutions, such as, for example, dilute sodium hydroxide solution or soda water.

The spatial separation of the cationic superabsorbent material (a) from the basic material (d) is preferably carried out in the same manner described above. enclosed manner in which the spatial separation of the anionic superabsorbie ^¬ leaders material (a) from the acidic material (c) is realized.

The amount of basic material (d) relative to the amount of cationic superabsorbent material (a) is preferably chosen so that after triggering the trigger system (iv) the degree of neutralization of the superabsorbent material (a) is at least 10%, preferably at least 20%, more preferably at least 30%, more preferably at least 40%, and most preferably at least 50% reduced. In the case of a cationic superabsorbent material (a), a degree of neutralization of X mol% means that X mol% of the base groups present in the superabsorbent material (a) are in the form of the corresponding acid.

According to a third particular embodiment of the inventive dehydrable hygiene articles, the triggering system (iv) comprises, in addition to the superabsorbent material (a), preferably spatially separated from the superabsorbent material (a), preferably neutral salt (e) or one of the water-absorbent material (a ) spatially separated, preferably neutral saline solution (f), wherein the triggering of the trigger system is effected in that the salt (s) or the salt solution (f) is allowed to come into contact with the hydrogel.

Also, the contact of neutral salts with a swollen, superabsorbent material can lead to dehydration. For example, if neutral salts of monovalent cations are used, such as NaCl, then osmotic pressure is the driving force for depleting the superabsorbent material. On the other hand, if salts of multivalent cations, such as, for example, aluminum salts, are used as neutral salts in combination with anionic, superabsorbent materials, it is above all the crosslinking of the anionic groups by the multivalent cations that drives the superabsorbent material. In this particular embodiment of the dehydrable hygiene article according to the invention, the superabsorbent material (a) used is preferably the crosslinked, partially neutralized polyacrylate described above in connection with the anionic superabsorbent material (a).

In the context of the present invention, a "neutral salt" is preferably understood to mean salt which does not contain any H ⁺ ion as cation and also no anions selected from the group consisting of OH ^" ions, CO ₃ ^2" ions, HCO ₃ ^" Ions and anions of organic acids, such as acetate or lactate ions. In this connection, it is preferred that the cation of the neutral salt has a pKa of at least 2, more preferably at least 4, even more preferably at least 6, and most preferably at least 8, while the anion of the neutral salt has a pK _b of at least 6, more preferably at least 8, even more preferably at least 10, and most preferably at least 12. These "neutral salts" are preferably salts comprising a metal cation and anions selected from the group consisting of chloride, bromide, iodide, sulfate, sulfite, nitrate or nitrite The term "neutral salt" as used herein therefore, it is understood that it encompasses salts which do not comprise an H ⁺ ion as cation and also no anions selected from the group consisting of OH, CO ₃ ^{2 "} , HCO ₃ ^" and organic acids However, when dissolved in water to lead to a pH of 7.0 different, such as FeCl ₃ . Neutral salts preferred according to the invention include salts whose cations are selected from the group consisting of Na ⁺ , K ⁺ , Li ⁺ , Ca ²⁺ , Mg ²⁺ , Al ³⁺ , Fe ²⁺ , Fe ³⁺ , Zn ²⁺ , Cu ⁺ and Cu ²⁺ and their anion are selected from the group consisting of Cr, Br ^' , I \ F, SO ₄ ^{2 "} , HSO ₄ ^" , NO ₃ ^" , NO ₂ ^" , HPO ₄ ^{2 "} and H ₂ PO ₄ ^" , where the anions and the cations can be combined as desired. Also, salts comprising mixtures of at least two of the abovementioned cations and / or mixtures of at least two of the abovementioned anions are conceivable as neutral salts. Particularly preferred neutral salts (e) are selected from the group consisting of polyvalent salts such as calcium chloride, magnesium chloride, iron (II) chloride, iron (III) chloride, aluminum chloride, calcium sulfate or aluminum sulfate, or monovalent salts such as sodium chloride, Potassium chloride and lithium chloride, with polyvalent, especially divalent or trivalent salts being most preferred.

The amount (based on the cations) of preferably di- or trivalent salt (s) in the hygiene article according to the invention, based on the anionic groups in the superabsorbent material (a), preferably based on the carboxylate groups in the partially neutralized polyacrylates based superabsorbent Material (a) is preferably in the range of from 0.1 to 1 mole of cation per mole of anionic groups, preferably in the range of from 0.25 to 0.75 mole of cation per mole of anionic groups, and most preferably in the range of 0.3 to 0.5 moles of cation per mole of anionic groups. If aqueous salt solutions (f) are used, the amount of salt (s) in the aqueous salt solution (f) is preferably in a range from 10 to 50% by weight, particularly preferably in a range from 15 to 40% by weight. % and moreover preferably in a range of 20 to 30% by weight.

Here, too, the spatial separation between the salt (s) or the aqueous salt solution (f) and the superabsorbent material (a) preferably takes place in the manner already described in connection with the first particular embodiment of the hygiene articles according to the invention With regard to the spatial separation between the anionic superabsorbent material (a) and the acidic material (c) has been described.

The dehydratable hygiene article according to the invention may comprise, in addition to the abovementioned components, further components. Insofar as the hygiene article is a diaper, this advantageously still has Closures that can be used to attach the diaper around the waist of the wearer. Suitable closures include hook-and-loop fasteners, tape closures, buttons, snaps, mushroom and loop fasteners, and the like. Further, in the case of a diaper, the sanitary articles may include elastic leg bands which prevent leakage of excreted bodily fluids from the diaper.

It is further preferred according to the invention that the dehydratable hygiene article in the aqueous liquid impermeable lower layer (i) and / or in the aqueous liquid permeable upper layer (ii) has a sealed outlet which can be opened and after opening which after the release of the trigger system (iv) at least partially released aqueous liquid can be removed from the hygiene article. In the case of a diaper, the outlet is preferably located centrally as a hygiene article in the lower layer (i) impermeable to aqueous liquids in the crotch region. It is conceivable, however, to attach the outlet in the region of the aforementioned lateral edge.

Preferably, the outlet is a hole in one of the two layers i) or ii), which preferably has a diameter of at least 0.5 cm, particularly preferably at least 1.0 cm and moreover preferably at least 2.0 cm. In the case of the still unused hygiene article, this outlet is preferably closed by the fact that the hole is closed by means of an adhesive strip which, after use of the hygiene article, can be at least partially torn off in order to open the outlet. Furthermore, the outlet may be designed such that one of the two layers i) or ii) has a perforated area which can be torn open after the hygiene article has been used. In the simplest case, such an outlet exists in a perforated line located, for example, in the liquid impermeable lower layer (i). After use of the hygiene article, the lower layer (i) is torn apart in the area of this perforated line, so that after release of the hygiene article sen of the trigger mechanism released liquid can escape through the resulting gap. Such a perforated region can advantageously also be located in the lateral edge of a diaper. In addition to perforating certain areas, it is also advantageous to incorporate tear threads into individual layers.

A contribution to the solution of the abovementioned objects is also provided by a method for dehydrating a hygiene article comprising the method steps:

a. Triggering the trigger system (iv) in a dehydratable hygiene article according to the invention which has absorbed aqueous liquid,

b. Removing at least a portion of the at least partially released absorbed aqueous liquid from the sanitary article after triggering the trigger system (iv).

Preferably, the sanitary article is a diaper. Furthermore, it is preferred according to the inventive method that the removal of at least a portion of the at least partially released after the activation of the trigger system (iv) absorbed aqueous liquid from the hygiene article in step b. characterized in that the hygiene article is compressed, preferably by the Beauschlagung of the hygiene article with a pressure which is greater than the surrounding the hygiene article air pressure, or by wringing of the hygiene article. According to another embodiment of the inventive method, the removal is carried out by the action of a centrifugal force or by the evaporation of at least a portion of the released liquid.

The removal of the liberated liquids is preferably carried out for at least 5 minutes, more preferably at the earliest 30 minutes, and moreover preferably at the earliest 60 minutes after the triggering of the triggering system. If the dehydrogenatable hygiene articles of the invention has the outlet as described above, it is preferred that this outlet is only opened UNMIT ^¬ directly upstream removal of the released liquid.

Further contributing to the solution of the above-mentioned objects is an apparatus for dehydrating a dehydrable sanitary article including a superabsorbent material (a) comprising the device components: A) having a container

Al) a first opening, via which a dehydratable hygiene article, which has absorbed aqueous liquids, can be introduced into the container A),

A2) a device component for expelling released aqueous liquid from the hygiene article,

A3) a closable second opening in the lower third of the device, via which released aqueous liquids can escape from the container A),

B) optionally a trigger element, which makes it possible, after its release from the superabsorbent material (a), if it is present as a hydrogel, to release at least a portion of the absorbed aqueous liquid, as well as

C) optionally a device component with which an opening can be introduced into the hygiene article.

The container A) is preferably a bucket or another vessel open at the top, for example a toilet, into which aqueous liquids can be filled. The container preferably has a height in a range of 20 cm to 150 cm, particularly preferably in one Range of 30 cm and 100 cm and a diameter in a range of 10 cm to 100 cm, particularly preferably in a range of 30 cm to 80 cm. It is further preferred that the container is made of a Kunststoffmateri- al with a wall thickness in a range of 0.5 mm to 10 mm.

The first opening A1) of the container A) is preferably the entire cross section in the upper region of the container. However, it is also possible to use a container with a cover, wherein preferably centrally in the cover an optionally closable opening is attached, through which the swollen sanitary article can be introduced into the container.

The device component A2) for expelling released aqueous fluid is preferably a press or a centrifuge. Furthermore, for this purpose, a diaper garbage press can be used, as it is known for example from DE 296 07 480 Ul.

In the closable second opening A3) mounted in the lower third, preferably in the lower quarter and particularly preferably in the bottom region of the device, via which liberated aqueous liquids can exit from the container A), it is preferably a shut-off valve. If necessary, this opening can be connected to a sewer pipe in a fluid-conducting manner.

According to a particular embodiment of the device according to the invention this further comprises at least 1 cm, preferably at least 5 cm above the bottom of the container A) arranged parallel to the bottom tray which has holes and preferably extends over the entire bottom portion. The swollen hygiene products are placed on this shelf. If the absorbed liquid is now removed from the hygiene article by actuation of the component A2), the released liquid passes through the support in the direction of the bottom of the container A), from which it can then be removed after opening the outlet A3). According to another embodiment of the device according to the invention, the container A) is designed so that it has an adapter in the bottom region, by means of which the container can be placed on an open toilet. Furthermore, the bottom area in this case, a further, closable opening. If now the dehydratable hygiene articles according to the invention are given into the device after triggering of the triggering system (iv), after the device component A2) has been actuated, the released liquid passes directly through the opening in the bottom into the toilet.

Furthermore, in the case of the device according to the invention, it is preferable for the latter to have a trigger element B) inside the container A), which after its release from the superabsorbent material (a), if present as a hydrogel, at least a part of the absorbed aqueous Release fluid.

If the swollen article of hygiene is a hygiene article according to the first, second or third particular embodiment and comprises an encapsulated material (acidic or basic materials or salts), the trigger element may be those devices with which the encapsulated material can be released , If a material which is sensitive to electromagnetic radiation, in particular to UV radiation, is used as the capsule material, a suitable radiation source may be considered as the trigger element B).

Furthermore, it may be preferred according to the invention that the device has a further device component with which an opening can be introduced into the hygiene article. In this way, the outflow of the released liquid from the hygiene article can be facilitated. In principle, all punching devices are considered with which holes in the hygiene Particles, preferably holes in one of the two layers i) or ii) or through holes can be punched through the entire sanitary article.

The device according to the invention is preferably used for dehydrating the hygiene articles according to the invention, wherein it is particularly preferred for the second opening A3) to be connected in a fluid-conducting manner to a sewer line.

A contribution to the solution of the objects mentioned at the outset is also provided by a kit

a device according to the invention for dehydrating a hygiene article and one or more dehydratable hygiene articles according to the invention,

or

one or more dehydrator-sanitary hygiene articles according to the invention and, separate from the hygiene article, a trigger component,

or

a device according to the invention for dehydrating a hygiene article and a trigger component,

or

a device according to the invention for dehydrating a hygiene article, a dehydratable hygiene article according to the invention and, separated from the hygiene article present, a trigger component. With the trigger component is preferably a material wel ^¬ ches if it (a) in contact with the superabsorbent material in hygiene articles ^¬ occurs, in accordance with ERT 441.2-02 certain "Centrifuge Retention Capacity" (in the case of a particulate superabsorbent Material (a) determined for the total particle fraction) by at least 10%, more preferably by at least 25%, even more preferably by at least 50%, and most preferably by at least 70%.

Preferably, the trigger component is selected from the group consisting of an acidic material (c), a basic material (d), a salt (e) or a salt solution (f). Preferred acidic materials, basic materials or neutral salts or salt solutions are those compounds or solutions which have already been mentioned in connection with the second, third and fourth particular embodiment of the dehydratable hygiene articles according to the invention.

The invention will now be explained in more detail with reference to non-limiting figures.

FIG. 1 shows a hygiene article according to the invention in the form of a thread in cross-section at the level of the line A shown in FIG.

FIG. 2 shows a hygiene article according to the invention in the form of a diaper from above.

FIG. 3 shows another hygiene article according to the invention in the form of a diaper from above.

FIG. 4 shows a device according to the invention for dehydrating a hygiene article. As can be seen from FIGS. 1, 2 and 3, the hygiene article according to the invention comprises a lower layer 1 impermeable to aqueous liquids, an upper layer 2 permeable to aqueous liquids and an aqueous liquid arranged between the lower and upper layers 1 and 2 respectively Absorbent core 4. This absorbent core 4 preferably comprises a fiber material and superabsorbent polymer particles. In this case, the absorbent core preferably extends over that region of the lower layer 1 (this is facing away from the body side when the diaper is worn), which is located in the crotch area when the diaper is worn. Furthermore, the diaper has closures 6 and elastic leg bands 5.

In the dehydratable diaper according to the invention shown in FIG. 2, spherical capsules 3 in which there are neutral salts or acidic or basic materials are introduced in the region of the absorbent core 4. For example, if the capsules are destroyed by mechanical action, the encapsulated materials will contact the superabsorbent material in the absorbent core 4 causing the superabsorbent to drain away. The released liquid can emerge from the hygiene article, for example, via the permeable upper layer 2. The trigger system in the diaper shown in Figure 2 thus consists of the superabsorbent material contained in the absorbent core 4 and the capsules 3. It is also conceivable that the sanitary article has closable outlets (not shown) through which liquids can escape.

According to FIG. 3, in the dehydratable diapers according to the invention, a component influencing the absorption capacity of the superabsorbent material, such as an acidic, basic or neutral salt, may also be contained in the form of elongated tubes 3. It is also conceivable to integrate this component into the lower layer impermeable for aqueous liquids (i) and / or the upper layer (ii) permeable to aqueous liquids, or in another form with one of these two layers or with two layers in Ver ^¬ connection to bring.

The device according to the invention for dehydrating a swollen hygiene article comprises a container 6, which preferably has the shape of a bucket (see FIG. 4). The container is open at the top in the embodiment shown in FIG. 4, so that hygiene articles 13 used via the opening 7 can be introduced into the container 6. The container advantageously has a holey tray 12 on which the sanitary articles 13 are placed. By means of a suitable pressing device, which in the embodiment of the device according to the invention shown in FIG. 4 is a punch 10 which can be pressed in the direction of the tray 12 by means of a threaded screw 11 and a rotary knob 9, the diapers can be compressed become. When the sanitary articles 13 are compressed between the punch 10 and the tray 12, (provided the triggering system has previously been triggered) the absorbed liquid passes through the holes of the tray 12 and enters the area of the bottom of the container 6 via the outlet 8, which can be connected, for example via a pump with a Abwasserleirung, the released liquid can be removed from the device.

test methods

Determination of the compressibility factor

The device for determining the compressibility factor of a hygiene article consists of a bottom sealed Plexiglas cylinder with an inner diameter of 15 cm, a height of 40 cm and a wall thickness of 2 mm. At a height of 10 cm above the bottom of the cylinder there is a metal screen with a mesh size of 400 μm and a wire diameter of 0.25 mm from ADMAR EUROPE, Sohren, Germany, Art. 78185, wel It is firmly connected to the inner wall of the cylinder at a height of 10 cm above the ground. Furthermore, the device for determining the compressibility factor comprises a punch that can be inserted into the cylinder in a positive manner and is weighted with weights made of metal. The total weight of Plexiglas stamp and metal weight is 10 kg.

To determine the compressibility factor of a (non-used) sanitary article, 0.9% by weight NaCl solution (20 g per gram of the superabsorbent material contained in the sanitary article) is placed in the absorbent core of the sanitary article. After 60 minutes, the swollen sanitary article is placed in the Plexiglas cylinder so that it comes to lie on the metal mesh and loaded with the stamp. Subsequently, the height of the punch over the metal screen is determined (H ₁ ).

Subsequently, the hygiene article is removed from the cylinder and triggered the trigger system. Immediately after triggering the trigger mechanism, the diaper is returned to the cylinder.

60 minutes after triggering the trigger mechanism, the die is again placed on the diaper, with the released liquid now passing through the metal mesh into the bottom of the Plexiglas cylinder.

After another 15 minutes, the height of the punch over the metal screen is again determined (H ₂ ).

The compressibility factor K is defined as K = (H ₁ ZH ₂ )

Claims

claims

1. A dehydrated hygiene article comprising:

i) an aqueous layer impermeable bottom layer, ii) an aqueous liquid permeable top layer, iii) an aqueous liquid absorbing core disposed between the bottom and top layers, and iv) a triggering system comprising a superabsorbent material (a), which is capable of absorbing aqueous fluids to form a hydrogel, wherein upon initiation of the triggering system from the superabsorbent material (a), when present as a hydrogel, at least a portion of the absorbed aqueous fluid can be released,

wherein the hygiene article comprises at most 50% by weight of another superabsorbent material (b), based on the total weight of superabsorbent material (a) and superabsorbent material (b), which would be capable, after triggering the trigger system (iv ) to absorb the at least partially released aqueous liquid, optionally after triggering a further, different from the trigger system (iv) triggering system, at least partially to form a hydrogel.

2. A dehydrated hygiene article comprising:

i) a lower layer impermeable to aqueous liquids, ii) an upper layer permeable to aqueous liquids, iii) an absorbent core disposed between the lower and upper layers, and iv) a triggering system comprising a superabsorbent material (a) capable of absorbing aqueous fluids to form a hydrogel, wherein after triggering the triggering system from the superabsorbent material (a), if present as a hydrogel, at least a portion of the absorbed, aqueous

Liquid can be released

wherein the sanitary article has a compressibility factor of at least 1.1 determined according to the test method described herein.

The dehydrable hygiene article according to claim 1 or 2, wherein the sanitary article is a diaper.

4. Dehydratable hygiene article according to one of the preceding claims, wherein the trigger system (iv) is an anionic superabsorbent

Material (a) whose absorption properties depend on the pH, and an acidic material (c) spatially separated from the superabsorbent material (a), and wherein the triggering is effected by allowing the acidic material (c) to to contact the hydrogel.

A dehydrable personal care article according to claim 4 wherein the superabsorbent material (a) is a cross-linked, partially neutralized polyacrylate and the acidic material (c) is citric acid.

6. A dehydratable diaper according to any one of claims 1 to 3, wherein the triggering system (iv) is a cationic superabsorbent material (a), the absorption properties of which depend on the pH, as well as a spatially separated from the superabsorbent material (a) Material (d) and whereby the triggering thereby it follows that the basic material (d) is allowed to contact the hydrogel.

A dehydrable hygiene article according to any one of claims 1 to 3, wherein the triggering system includes, in addition to the superabsorbent material (a), a neutral salt (e) spatially separated from the superabsorbent material (a) or spatially separated from the superabsorbent material (a) neutral salt solution (f), and wherein the triggering is effected by allowing the salt (e) or saline solution (f), respectively, to contact the hydrogel.

A dehydrable hygiene article according to any one of the preceding claims, wherein the aqueous layer impermeable lower layer (i) and / or the aqueous liquid permeable upper layer (ii) has a sealed outlet which can be opened and over which, after opening after triggering the trigger system (iv) at least partially released aqueous liquid can be removed from the hygiene article.

9. A method for dehydrating a hygiene article comprising the method steps:

a. Triggering the trigger system (iv) in a dehydrogenatable hygiene article according to any one of claims 1 to 8, which has absorbed aqueous liquid,

The method of claim 9, wherein the removal is by the compression of the sanitary article.

11. The method according to claim 10, wherein the compression takes place by the control of the hygiene article with a pressure which is greater than the air pressure surrounding the hygiene article, or by wringing out of the hygiene article.

12. The method of claim 9, wherein the removal is effected by the action of a centrifugal force.

13. The method of claim 9, wherein the removal is carried out by the evaporation of at least a portion of the released liquid.

14. A device for dehydrating a superabsorbent material (a) containing dehydratable sanitary article comprising the device components:

A) having a container

Al) a first opening, via which a dehydratable hygiene article, which has absorbed aqueous liquids, is introduced into the container A),

A2) a device component for expelling released aqueous liquid from the hygiene article, A3) a closable second opening, which is located in the lower third of the device, over the liberated aqueous

Liquids can escape from the container A),

B) if appropriate, a trigger element which, after its release from the superabsorbent material (a), if present as a hydrogel, allows at least a portion of the absorbed aqueous liquid to be released, and C) optionally a device component with which an opening can be introduced into the hygiene article.

The apparatus of claim 14, wherein the device component (A2) for expelling released aqueous fluid is a press or a centrifuge.

16. The apparatus of claim 14 or 15, wherein the trigger element (B) is a source of electromagnetic radiation.

17. Use of a device according to one of claims 14 to 16 for dehydrating hygiene articles.

18. Use according to claim 17, wherein the second opening (A3) is fluidly connected to a sewer pipe.

19. Kit comprising a device according to one of claims 14 to 16 and a dehydratable hygiene article according to one of claims 1

^' to 8.

20. Kit comprising a dehydratable hygiene article according to one of claims 1 to 8 and, separated from the hygiene article present, a trigger component.

21. Kit comprising a device according to one of claims 14 to 16 and a trigger component.

22. Kit comprising a device according to one of claims 14 to 16, a dehydratable hygiene article according to one of claims 1 to 8 and, separated from the hygiene article present, a trigger component.

A kit according to any one of claims 20 to 22, wherein the triggering component (iv) is selected from the group consisting of an acidic material (c), a basic material (d), a salt (e) or a saline solution (f).