Method for detection of unfastening or removal of absorbent article from the body

[0001] The invention relates to a system for detecting when an absorbent article is detached or removed from the wearer's body. The system includes an absorbent article comprising an absorbent structure sandwiched between a liquid-permeable top sheet and a liquid-impermeable back sheet and a belt-type fastening device comprising at least a first portion of the belt and a second portion of the belt. The first part of the belt includes fastening means adapted to be attached directly to the second part of the belt. The first and second parts of the strap are adapted to be fastened when the product is attached to the wearer. The system also includes a remote receiver.

BACKGROUND OF THE INVENTION [0002] Absorbent articles, such as diapers for children and adults, sanitary napkins and urological napkins, are well known in the art and are widely used. Most of these products are used today as disposable products. The nature of one-time use of such products has led to the development of a wide range of different products to meet specific requirements, e.g. in the care of newborns and infants, as well as among adults suffering from incontinence. The main task of such absorbent articles is normally to absorb, maintain and isolate excreted waste products such as urine, feces or blood.

[0003] Absorbent articles that respond to an event, such as urination, defecation, associated with the absorption of liquid in or on a product are also well known in the art. This reaction is typically a signal after an event has occurred and is based on the measurement of, for example, humidity, temperature or mass change. The signal may be an optical signal, including visual signals, an audible signal, a chemical signal or an electrical signal. The signal can provide feedback to the wearer or guardian about the occurrence of the incident, which facilitates the cleaning procedure for both parties.

[0004] Many of these products contain sensors that can operate in many different ways. For example:

WO 2004/021944 discloses a disposable absorbent structure for detecting humidity, comprising at least one layer and at least one detection device, comprising a magnetoelastic film. The absorbent structure provides a means and method for monitoring the status, e.g. humidity, of at least one biological analyte and / or at least one chemical analyte in an absorbent article.

EP 1 901 689 B1

WO 00/16081 discloses a system comprising a resonant circuit that is at least partly formed of moisture sensitive material whose electrical resistance increases when the material comes into contact with moisture. The system also includes at least one electronic sensor for detecting the presence of moisture and at least one reading device for obtaining information from the sensor about the presence of moisture.

US 5808554 discloses a diaper pants sensor for detecting moisture conditions in diapers or underwear, comprising a capacitive sensor located in a housing and attached to the outer surface of the monitored part of the garment. The sensor consists of two essentially solid coplanar guide plates attached to a common substrate with a very large dynamic range. When the inside of the garment becomes wet, the capacity between the spaced apart conductors increases above the pre-set value, at which point the sensor delivers a signal to the transmitter or an alarm.

[0005] One particular group of direct users or users of such absorbent articles includes psychiatric patients suffering from dementia or other mental illnesses who additionally suffer from various degrees of urinary incontinence. These people may not experience any inhibition of the excretory function and may remove their urological cartridges, either before urinating / defecating or immediately after, thereby contaminating themselves and / or the environment, which necessitates unpleasant cleaning activities for care personnel.

[0006] In this case, the presence of a "detachment" sensor or sensor in the urological cartridge can be considered a great advantage and advantage. Such a sensor will register and raise an alarm when the product for those suffering from incontinence is removed or completely removed from the wearer's body.

[0007] The presence of a removal sensor can also be considered as an advantage for normal users, such as children or people suffering from incontinence problems, when, for example, accidental removal of an absorbent article during sleep will trigger an alarm signal.

[0008] None of the prior art items listed above describes products comprising a sensor for detecting detachment or complete removal from a wearer's body.

SUMMARY OF THE INVENTION [0009] The invention relates to a system for detecting the moment of detachment or removal of an absorbent article from a wearer, the system comprising an absorbent article comprising an absorbent structure sandwiched between a liquid-permeable top sheet and a liquid-impermeable back sheet and a strap type fastening device comprising at least the first part of the strap and the second part of the strap. The first part of the belt includes fastening means adapted to be attached directly to the second part of the belt. The first and second part of the strap are

EP 1 901 689 B1 adapted to be fastened when the product is attached to the wearer. The system also includes a remote receiver. The absorbent article further comprises at least one detection device and at least one resonant object, the at least one sensor device being an electric resonant circuit. The at least one detection device is capable of detecting the first resonant frequency generated in the electromagnetic field generated by the resonant object when the first part of the belt and the second part of the belt of the belt type fastening device are fastened. At least one detection device is capable of detecting a second resonant frequency created in the electromagnetic field generated by the resonance object when the first part of the belt and the second part of the belt of the belt type fastening device are detached. The detection device is able to determine whether the resonance frequency is the first resonance frequency or the second resonance frequency. The absorbent article further comprises at least one transmitting device capable of sending an alarm signal to the remote receiver when the detecting device detects a second resonant frequency.

According to another embodiment of the invention, the absorbent article further comprises at least one detection device and at least one resonance object, wherein the at least one detection device is a magnetoelastic film. At least one detection device is capable of detecting the first resonant frequency created in the electromagnetic field generated by the resonant object when the first part of the belt and the second part of the belt of the belt type fastening device are fastened. At least one detection device is capable of detecting a second resonant frequency created in the electromagnetic field generated by the resonance object when the first part of the belt and the second part of the belt of the belt type fastening device are detached. The detection device is able to determine whether the resonance frequency is the first resonance frequency or the second resonance frequency. The absorbent article further comprises at least one transmitting device capable of sending an alarm signal to the remote receiver when the detecting device detects a second resonant frequency.

[0010] According to an embodiment, the system comprises (a) an absorbent article comprising at least one absorbent layer, a movable object, such as a fastening system, one or more detection devices, one or more transmitting devices, and (b) a remote receiver.

[0011] In one embodiment, one or more detection devices detect oscillation differences resulting from an increase or decrease in the magnetic field of the undercoating corresponding to the displacement of said object. In such an embodiment, the preferred detection device is magnetoelastic film.

[0012] In another embodiment, the one or more detection devices comprise a resonant circuit comprising inductive, capacitive and connecting elements, wherein at least one of said elements is adapted in such a way that the electrical properties

The said element or said elements change when the absorbent article is displaced or removed.

[0013] In one embodiment of the invention, the system includes a remote receiver which is a hand-held unit.

[0014] In another embodiment, the system includes a remote receiver, which is a stationary unit.

[0015] In another aspect of the invention, the invention relates to the use of said system in the care of children and adults suffering from incontinence, excretion and / or mental illness such as dementia.

BRIEF DESCRIPTION OF THE DRAWINGS [0016]

Fig. 1 shows a strip diaper (1) having a general T-shaped configuration and comprising an absorbent structure (2) and a belt-shaped fastening device (3).

Fig. 2 shows the diaper (1) just before the front part (19) of the diaper (1) is attached to the strap (3).

Figs. 3a and 3b show an embodiment of the "open diaper" of the strip diaper (1) in its unmounted state, Fig. 3a and in its mounted state, Fig. 3b.

Fig. 4 (a) and (b) are front and side illustrations of the hook fastening device (401) containing the carrier material.

Fig. 5 (a) and (b) are front and side illustrations of another embodiment of a fastening device in which the permanent magnet is released from the hook material.

DETAILED DESCRIPTION OF THE INVENTION

Definitions [0017] The term "absorbent article" as used herein refers to a device that absorbs, maintains and contains excreted metabolic products or body secretions, such as urine, feces or blood.

In use, the device is positioned close to the body or otherwise located close to the wearer's body.

[0018] The term "disposable" refers to an absorbent article that is not expected to be washed, restored or reused as the absorbent article. Such a product

Absorbent is intended to be discarded after one use. However, single use does not preclude recycling, processing of the product into compost or other disposal in an environmentally sound manner.

[0019] The terms "sensor" and "detection device" or "detector" are used interchangeably and here means a device that is capable of detecting an event or alternatively a parameter that is associated with the event. An event-related parameter is any measurable signal that is correlated with the occurrence of an event within the system, i.e. a signal caused by the wearer's secretions or components. Sensors include embodiments responsive to one or more specific input signals.

[0020] The term "detection" refers to means and methods capable of detecting an event or event related parameter, using, for example, a detection device.

[0021] The term "moisture" here means the state of being wet, moist, or alternatively, containing a liquid or covering with a liquid, especially water.

[0022] The term "diaper" here means an absorbent article generally worn around the lower torso by newborns, infants, and persons suffering from incontinence.

[0023] The term "user" as used herein may refer to (a) a direct user or wearer of an absorbent article or alternatively (b) an indirect user or caregiver who is responsible for the care of a wearer of absorbent article.

[0024] The term "magnetostriction" refers here to the usual phenomenon observed in magnetic materials that occurs when the dimensions of the magnetic material change after magnetization. The size or size of the dimensional change depends on the temperature, the magnetization of the material and, of course, on the material's properties. Magnetostriction is the result of the interaction between the magnetic moments of atoms in the material.

[0025] The term "magnetoacoustic resonant frequency" refers to the oscillation frequency that occurs when a magnetic material is excited by a magnetic field and stores energy in a magnetoelastic mode. When the magnetic field is turned off, the material exhibits a damped oscillation at a specific frequency called the magnetoacoustic resonance frequency.

[0026] The term "carrier material" as used herein refers to the material or fabric covering the hook fastening device shown in Fig. 4. The carrier material may be, for example, non-woven, spunbond type, with a specific weight of about 25-60 g / m². Preferably it is made of polypropylene fibers. However, any conventional material can be used.

[0027] As used herein, the term "resonant circuit" refers to an electrical circuit in which the impedance or damping of said circuit is frequency dependent.

[0028] The term "resonant object" refers to an electrical, magnetic, mechanical, magnetostrictive or other object in which the attenuation of said object depends on frequency.

Terminology and subject matter of the invention

Absorbent article [0029] In normal use, the absorbent article, such as a diaper, diaper-type pants, urological pad, sanitary napkin, is used to absorb, hold and isolate excreted metabolic products, e.g. urine, menstrual blood, wound fluid and abrasions.

[0030] In one embodiment of the absorbent article, the absorbent layer contained in the absorbent article comprises at least one receiving layer, at least one storage layer, and optionally one or more transporting layers. The receiving layer is intended to receive fluid and distribute said fluid to the transport and storage layers. In another embodiment, at least one of the above receiving, storage or transporting layers contains 0-100% of superabsorbent material. In further embodiments, said receiving, storage or transporting layers may comprise 0-95%, 20-100%, 0-30% or 30-40% of superabsorbent material.

Hook and loop fastening [0031] Hook and loop fastening refers to a VELCRO fastener, i.e. a fastening method in which one of the surfaces to be joined contains a plurality of small hooks. The second surface contains many small loops.

Magnetoelastic film [0032] Magnetoelastic film is one type of magnetoelastic sensor. Magnetoelastic sensors have been described by Grimes et al. (Biomedical Microdevices, 2: 51-60, 1999).

[0033] When the magnetic material is excited by an external magnetic pulse or magnetic field, it stores magnetic energy in magnetoelastic mode. When the field is turned off, the material exhibits a damped oscillation with a specific frequency, a magnetoacoustic resonance frequency. These oscillations produce a magnetic flux that changes over time, which can be remotely detected by the receiving coil. Changes in resonance frequency can be monitored to measure or detect many

EP 1 901 689 B1 environmental parameters. Temperature, pressure, and viscosity measurements using this method are described in Grimes et al. (Biomedical Microdevices, 2: 51-60, 1999).

[0034] It is also possible to excite the material with a continuous magnetic field exhibiting a frequency corresponding to or close to the magnetoacoustic resonance frequency and measuring the material response, such as a suppressed magnetic response between pulses. At resonance frequency, the material response is maximum.

[0035] In addition, when a magnetic field is used for a magnetic material, such as a ferromagnetic material, the dimension of the material changes. This effect is called magnetostriction, as defined earlier. The size of the changes in the dimensions of the material depends on the constant magnetostriction.

[0036] Magnetostriction can be observed in many materials, for example iron, nickel, cobalt, rare earths as well as various alloys such as nickel iron alloys, ferrites, e.g. spinel type ferrites (Fe3O4, MnFe2O4) and silicon alloys -żelazowe.

[0037] The magnetoelastic film used in the invention exhibits magnetostriction and may also contain amorphous magnetic material, alloys or mixtures thereof. The amorphous magnetic material is very easy to saturate magnetically and it exhibits small magnetic anisotropy. In alloy amorphous magnetic materials, magnetostriction is also present, and the magnitude of the magnetostriction depends on the exact composition of the alloy. Examples of amorphous alloys are Metglas materials. such as Fe40Ni38Mo4B18, e.g. Metglas 282MB ™ (Honeywell Amorphous Metals, Pittsburg, PA, USA), FeCo) 80B20, (CoNi) 80B20, (FeNi) 80B20.

[0038] One embodiment of the invention uses METGLAS® material from Honeywell (Honeywell Amorphous Metals, Pittsburg, PA, USA) as a magnetoelastic material such as METGLAS® 2826MB.

[0039] Suitable magnetoelastic films can be any films having non-zero magnetostriction and high magnetoelastic coupling, such as nickel iron alloy, rare earth metals, ferrites and various alloys and mixtures disclosed above. A suitable film thickness for said magnetoelastic films is about 0.01-1000 μm, e.g. from about 0.01 to about 200 μm, e.g. e.g. from about 5 to about 100 μm, e.g. e.g. from about 0.01 to about 100 μm. The thickness of the foil can be much smaller than the width and length.

[0040] One way to enhance the magnetostriction effect is to use a magnetic primer field. The magnetic backing field has an optimal magnetic backing field, providing an optimal magnetoacoustic effect, and also gives an optimal signal from the magnetoacoustic effect (Grimes et al., Sensors and Actuators, B71: 112-117, 2000). In one embodiment, the magnetic backing field is generated by a permanent magnet placed in association with the magnetoelastic film. The permanent magnet can be in the form of small metal pieces of different types

EP 1 901 689 B1 shapes and sizes (such as those used at home as kitchen appliances to attach on the fridge), powder, granules, foil, magnetic ink and in other forms.

DESCRIPTION OF THE INVENTION [0041] The invention relates to an alarm signal detection and transmission system when the absorbent article is detached or removed from the wearer's body.

[0042] According to the invention, the system comprises (a) an absorbent article comprising at least one absorbent layer, a displaced object such as a fastening system, one or more detection devices, one or more transmitting devices, and (b) a remote receiver that houses the receiving coil.

[0043] In one embodiment, one or more detection devices detect oscillation differences resulting from an increase or decrease in the magnetic field of the backing corresponding to the displacement of said object. The said detection device may be small, optionally detachable and reusable, it may contain a wireless battery-free circuit, it is connected to an alarm transmitter and a remote receiver. The detection device may be wrapped or encapsulated to protect against damage by, for example, mechanical pressure, which could affect the resonance frequency. Suitable encapsulation methods include encapsulation in the form of overlays, such as commercially available overlays from, for example, Sensomatic (Vienna, Austria) or a similar product. The housing is always designed or chosen by a specialist to match the specific embodiment.

[0044] In another embodiment, a magnetoelastic film is used as the detection device. One or more sensors can be used. In addition, a thin web of magnetoelastic material can be used. Magnetoacoustic resonance frequency, for example for a thin web of magnetoelastic material, is inversely proportional to the length of the web. Thus, it is possible to obtain different resonance frequencies in one detection device. A typical magnetoelastic material that can be used in the invention is METGLAS® from Honeywell (Morristown, NJ).

[0045] In one embodiment, a magnetic backing field is generated and a resonance object is provided by, for example, the presence of one or more permanent magnets that are connected to or arranged in a defined place relative to one or more sensors. The permanent magnets are attached to one or more fastening devices of said absorbent article in any manner commonly used in the field, or they can be used as a fastening device. Permanent magnets can be in the form of small metallic pieces of various shapes and sizes, powder, granules, foil, magnetic ink or other forms.

[0046] When the fastening devices are moved away from the sensors, as when the absorbent article is unfastened, the magnetic field will change and the sensors will detect oscillation differences resulting from the increase or decrease of the backing field corresponding to the displacement of said fastening devices. For example, in pant diapers, the sensor response may include a resonant object that detects whether a fastening device, such as a tape or strap, is in contact with the diaper front panel.

[0047] This effect is supported by research in the literature (Chizumi, S., "Physics of Ferromagnetism", Oxford, Oxford University Press, 1997; O'Handley, RC., "Modern Magnetic Materials, Principles and Applications", New York, John Wiley & Sons Inc., 2000). Comparison of the magnetoacoustic effect that occurs when a magnetic primer field is applied for the first time, or alternatively, as in this example, obtained by a permanent magnet (a) near a magnetoelastic film (such as METGLAS® film) and then (b) in said film , shows that the signal from magnetoacoustic oscillations increases significantly and that it is even possible to observe higher harmonics of magnetoacoustic oscillations. This is because the magnetoelastic effect is amplified when the magnetic field is increased in the sample.

[0048] The amplitude of the magnetic field used should be large enough to magnetize the material, such as a magnetoelastic film, to a certain level in order to obtain a sufficiently large change in the size of the material. Specific magnetic fields can therefore be optimized for each selected magnetostrictive material.

[0049] The magnetic field amplitude, for example 0.06 mT, in the film was rated by the inventors as large enough to detect magnetoacoustic signals. 1 kHz magnetic pulses with a 20% duty cycle are typically used, but other frequencies and duty rates can also be used. A magnetic field in the range of 0.05 mT to 0.1 mT will ensure sufficient magnetization in the magnetoelastic film. The exact value depends on the material selected in the magnetoelastic film and can thus be optimized for each embodiment. The exact values ​​of the pulse frequency, duty cycle and field amplitude in the film can be optimized in a similar way when the magnetoelastic film material and sensor system are selected. Also the distance of the remote alarm signal receiver (such as a manual or stationary unit) should be taken into account, as well as the value of the maximum distance between the remote receiver and the magnetoelastic film should be defined when optimizing other parameters in various embodiments. The minimum distance is on the outer surface of the absorbent article. Detection can be designed to provide the widest coverage coverage of about xm, where x is selected for example by caregivers, by proper design of the excitation and receiving coils.

[0050] In one embodiment, the detection may be designed to provide the largest coverage range of about xm, where x is about 0-10 m, such as about 0, 1, 2, 3, 4, 5, 6 , 7, 8, 9.10 m.

[0051] In another embodiment, the detection may be designed to provide the largest coverage range of about xm, where x is about 0-5 m.

[0052] In another embodiment, the detection may be designed to provide the largest coverage range of about xm, where x is about 0-1 m, such as about 0, for example; 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9; 1 m.

[0053] Detection of the magnetoacoustic resonance frequency is provided by a receiving coil located in a remote receiver that detects the response of the material.

[0054] In one embodiment of the invention, the system includes a remote receiver which is a hand-held unit. A typical remote receiver in the form of a hand-held unit has already been described in document WO 2004/021944 A1, which is covered by reference title. The signal generator is connected to the detection circuit so that the detection circuit "knows" when the signal is sent to the excitation coil. In addition, a remote receiver, such as in the form of a hand-held unit, can be designed to minimize the magnetic coupling between the magnetic backing field, such as from a permanent magnet, and the receiving coil. The position of the receiving coil relative to the magnetic backing field can be optimized for the maximum signal from the foil and the minimum signal due to the magnetic field from the backing field.

[0055] In another embodiment of the invention, the system includes a remote receiver, which is a stationary unit in a suitable position relative to both the wearer and caregiver (e.g. in the wearer's or patient's bedroom) or only to caregivers (e.g. in the room care staff).

[0056] In another embodiment, the one or more detection devices comprise a resonant electrical circuit instead of a magnetoelastic film. Said embodiment comprises the first and second electrodes of the LC circuit or LRC circuit. Said first and second electrodes are positioned as part of the fastening device of said absorbent article or in its vicinity. The fastening device is further provided with a conductive area, e.g. metal foil, so that when the fastener of the absorbent article is properly closed, the conductive area contacts both the first and second electrodes, thus shorting said LC circuit. When said LC circuit is excited by a query signal, the response signal will be zero or close to zero, and the frequency of this signal will be different from the frequency of the detectable signal when the fastening device of said absorbent article is open or improperly closed. This query signal is a signal to excite the LC circuit. The excited LC circuit, when excited, emits a response signal in frequency

EP 1 901 689 B1. This response signal is read by a reading device, which may be part of a remote receiver.

[0057] In a further embodiment, said system comprises an absorbent article equipped with an electric resonance circuit, such as an LC or LRC circuit. Said electric resonance circuit is small enough to be located as part of the fastening device of said absorbent article. The fastening device is further equipped with shielding means, e.g. metal foil or metal layer, so that when the fastening device of the absorbent article is properly closed, the shielding area is in such a place that it covers all or so much of the electric resonance circuit that the shielding means diffuse the incoming signal in radio frequency, so that the underlying electric resonance circuit does not resonate, or resonates very little.

[0058] The electric resonant circuit is preferably provided in so-called "Strip landing zone", ie in the area of ​​the absorbent article fastening device in which the adhesive fastening wing is attached. In the hook and loop system, the "loop zone" will be the appropriate zone.

According to another object of the invention, the invention relates to the use of said system in the care of children and adults suffering from incontinence, excretion and / or mental illness such as dementia.

EXAMPLES [0060] Examples (and accompanying figures) 1-5 below illustrate the invention and describe several possible embodiments of said absorbent article which is included in the system of the invention. These examples are present to illustrate the invention but are not intended to limit the invention described herein in any way.

[0061] Figures 1 and 2 (together) and Figure 3 show two different embodiments of the invention.

Example 1 [0062] In Figure 1, the strip diaper (1) has a general T-shaped configuration and comprises an absorbent structure (2) sandwiched between the liquid-permeable top sheet (4) and the liquid-impermeable back sheet (5). The belt diaper further comprises a belt-shaped fastening device (3). In the embodiment shown, the strap consists of the first and second parts (7, 8) of the strap.

[0063] The belt diaper further comprises a fastening system in the shape of a belt fastening hook (6) that adheres directly to the second portion (8) of the belt. The fastening system further includes hooks (12, 13) fastening the diaper. The strip contains a non-woven laminate with a non-woven spunbond layer sandwiched between thermally bonded two non-woven carded

EP 1 901 689 B1 in layers. In this embodiment, the non-woven layers consist of polypropylene fibers. Each layer has a specific mass of about 22 g / m2².

[0064] The diaper-fastening hooks (12, 13) are placed on the liquid-permeable upper sheet (4) of the diaper (1) and attach directly to the outwardly directed portion of the strap (3) as shown in figure 2. Each diaper-fastening hook contains a permanent magnet (15, 16) sandwiched between the liquid-permeable top sheet (4) and the outer surface of the diaper-fastening hook (15, 16). Further details of this arrangement are shown in figures 4-5.

[0065] The permanent magnet may be in the form of small metal pieces of various shapes and sizes, powder, granules, foil, magnetic ink and other forms.

[0066] A plurality, for example three magnetoelastic films, are arranged inside the first strip part (7), between a carded non-woven layer facing away from the user during use and a central non-woven spunbond layer in the strip laminate. This is illustrated by the three rectangular magnetoelastic films (20) shown in figures 1 and 2. In further embodiments of the aforementioned embodiments, a plurality of magnetoelastic films can be arranged in the longitudinal or transverse direction of the fastening system. Placing them longitudinally allows users of various sizes to use an absorbent article without significantly affecting the functionality of the invention.

[0067] In all embodiments, the films are permanently encapsulated to protect them from mechanical pressure.

[0068] In another embodiment, several additional sensors (20), which may have a different resonant frequency, are placed in the absorbent article. Placement can be at the back, front and sides of the diaper.

[0069] The placement of the sensors 20 in figure 1 should be considered only by way of example.

[0070] The band diaper further comprises a front portion (19) which should be worn against the wearer's abdomen during use. The back part (17) that should be worn at the wearer's back during use and the crotch part (18) located between the front part (19) and the back part (17) that should be worn at the wearer's genitals during use. The strap (3) is attached to the back (17) of the diaper (1).

[0071] Figure 2 shows the diaper (1) just before the front part (19) of the diaper (1) is attached to the belt (3). Figure 1 should also be a reference to other parts of the diaper. The first part (7) of the strap is attached to the second part (8) of the strap through the fastening hook (6) of the strap. In this way, many magnetoelastic films (20) are exposed and placed close to the diaper-fastening hooks (12, 13) and permanent magnets (15, 16). Absorbent core,

The liquid-impermeable back sheet and the liquid-permeable top sheet, shown in the strip diaper in Figure 1, may have, where appropriate, the same configuration as the open diaper described in figure 3.

[0072] The remote unit in the form of a hand unit or in the form of a stationary unit can then be used to determine the first frequency A which corresponds to the closed diaper. This frequency A can be used at any later stage to correlate new measurements of the second frequency B. If the first frequency A is lower than the second frequency B, the permanent magnets (15, 16) are displaced relative to many magnetoelastic films (20). This displacement may be correlated with an event in which the diaper fastening system is turned off, or in which the function of the fastening system has been reduced. When the diaper fastening system is turned off, the diaper is not fitted to the wearer's body and the risk of leakage is then much higher than before. The resulting alarm signal will cause the guardian to check the current situation of the wearer. In one embodiment, the frequency A is stored in a hand-held unit. In another embodiment, the frequency A is sent directly or indirectly to a computer that compares frequency A with the later measured frequency B.

[0073] Both frequencies A and B can also be compared with predefined values ​​corresponding to an open or closed / off diaper.

Example 2 [0074] Figure 3a and Figure 3b show another embodiment of the invention. Figure 3a shows a diaper with band wings (307, 308) and two fastening zones (320, 321) disposed on a liquid-impermeable back sheet (302). The band wings 307, 308 are furthermore provided with hook areas 307a, 307b. Each of the hook regions is further provided with a permanent magnet 340, 341. This arrangement is further described in connection with Fig. 4.

[0075] The loop fastening zones (320, 321) contain conventional loop material so they will not be further described. Two magnetoelastic foils 331, 332 are placed between the loop fastening zones 320, 321 and the liquid-impermeable back sheet. When the diaper is worn, the band-shaped fastening system (307, 308) with areas 307a, 307b of hooks and areas 340, 341 of permanent magnets and the loop zone (320, 321) of fasteners are close to magnetoelastic films. The frequency can then be set as described in example 1. When the diaper is unfastened, the displacement generates an alarm signal for the wearer or guardian as previously stated.

[0076] The wetting point is the surface area of ​​the diaper with which body fluid or secretions first come into contact. Of course, in practice it is not possible to determine any particular point or area in this regard, although it is generally accepted that body fluid or secretion will be delivered to the diaper in a given, restricted area. In general, this area

EP 1 901 689 B1 is displaced slightly towards the front of the diaper, both for male and female wearers. Since the dispersion of the liquid in the first absorbent layer, i.e. the receiving layer, is only slight, it is sufficient that this layer covers only the diaper area in which wetting is most likely to occur. Accordingly, such aspects can be analyzed and considered when arranging detection devices in an absorbent article, such as a diaper comprising the system of the invention.

[0077] The diaper illustrated in figure 3 consists of a liquid-permeable top sheet 301, e.g. a non-woven or perforated plastic film, liquid-impermeable back sheet 302, e.g. a plastic film or hydrophobic non-woven material and an absorbent structure 303, enclosed between two layers 301, 302.

[0078] The diaper is designed to wrap the lower part of the wearer's body in a manner of absorbent underwear. The diaper is equipped with a rear part 304, which when worn, is located on the back of the wearer, with a front part 305, which when worn is located at the front of the wearer and with a narrower part 306 of the crotch, which extends between the rear part cut 304 and the front portion 305 of the diaper and which, when worn, is in the wearer's crotch area, between his thighs. Fastening wings 307, 308, with hook material 307a, 308a are provided on the lateral edges 309, 310 of the back portion 304 extending in the longitudinal direction of the diaper, close to the back edge 311 of said diaper so as to allow attachment of the diaper in the desired form of pants. When the diaper is to be used, the fastened wings 307, 308 are attached to the outer surface of the diaper front portion 305, close to the front edge 312 of the waist, thereby holding the diaper completely around the wearer's waist.

[0079] The diaper shown in figure 3 further comprises pre-stretched elastic devices 313, 314 that extend along the longitudinal lateral edges of the diaper in the crotch portion 306. The resilient devices 313, 314 may consist of any suitable material, such as elastic foam, elastic bands or coated elastic threads. For convenience, the resilient devices 313, 314 are shown in a pre-stretched state.

[0080] The absorbent structure 303 consists of mutually different layers. Closest to the liquid-permeable upper sheet 301 is a thin cellulose downy layer 315 with a critical specific volume, large pore volume and low liquid distribution capacity. By critical specific volume is meant the specific volume at which the cellulose body will not collapse or stretch when it becomes wet. The cellulose fluffy mass with a high critical specific volume will retain the open structure of a large pore volume, even when wet.

[0081] Looking towards the liquid-impermeable back sheet 302, then there is the first absorbent layer 316, which consists of cellulose fluffy mass with a large pore volume, high wet elasticity and low liquid distribution capacity, and a second absorbent layer 317 consisting of cellulose fluffy mass with small pore volume, low elasticity on

EP 1 901 689 B1 wet and high liquid dispersibility. Both absorbent layers also contain superabsorbent material.

[0082] The first absorbent layer 316 has an oval shape and is generally located in the crotch portion 306 of the diaper, around a so-called wetting point. In other embodiments, said layer 316 has a rectangular shape or other suitable shape.

[0083] The first receiving layer, i.e. the receiving layer, thus acts in the diaper as a receiving area for the excreted body fluid or secretions.

[0084] Down CTMP (chemo-thermomechanical pulp), CF down, stuffing material or foam are suitable for use as the first absorbent layer. SAP can also be added to this layer in various proportions.

[0085] The first absorbent layer 316 may also contain 2-30%, for example 2-15% of the superabsorbent material based on the total dry weight of the layer in the area in which the superabsorbent material is mixed. The superabsorbent material can be distributed generally evenly throughout the layer, in at least one region or region thereof, and is intended to bind any liquid that remains in the layer, even if the layer has been drained through a second absorbent layer 317, which may be a transport layer.

[0086] As previously mentioned, the superabsorbent material in the first absorbent layer should preferably have a high gel strength to keep the fiber structure open when it becomes wet.

[0087] The second absorbent layer 317 also contains a superabsorbent material, which may be in the form of one or more layers of flakes, fibers, granules, powder, etc. The layer extends either over the entire area of ​​the absorbent layer 317, or is limited to at least one of it area. This area may, for example, be slightly larger than the absorbent layer 316 and, like said layer, may be limited essentially to a portion of the diaper crotch.

[0088] The proportion of superabsorbent material contained in the second absorbent layer 317 is preferably between 2 and 60%, preferably between 19 and 50%, calculated as part of the total dry weight of the layer.

[0089] The superabsorbent material in the second absorbent layer 317 preferably has a high gel strength, i.e. has the ability to swell substantially without normally occurring pressure forces, so as not to block or inhibit the distribution of liquid. A feature of these superabsorbent materials is that they have a high degree of crosslinking, which makes them harder to compress compared to a gel that has a lower degree of crosslinking.

[0090] The fluffy mass in the layer 317 of the second absorbent layer may comprise a substantially fluffy mass or some other absorbent material with a high liquid distribution capacity. The chemically produced fluff pulp from cellulosic material generally meets this requirement.

The final fibers can have a weight of 140-190 μg / m, a low degree of stiffness and low wet stability and a critical specific volume of less than 8 cm³/ g at 2.5 kPa pressure.

[0091] The second layer 317 may also contain a selected fluff pulp, such as CTMP pulp or chemical pulp.

[0092] In this way, the excreted body fluid or secretion is first collected in a first absorbent layer 316, which acts as a buffer or reservoir, wherein this layer is then drained as the second absorbent layer 317 absorbs and disperses liquid secretions.

[0093] It should be noted that the diaper illustrated and described is only intended to illustrate the invention and should not be construed to limit the scope of the invention. For example, the shape of the diaper and its construction may change in other respects. Similarly, the first absorbent layer 316 can fully cover the second absorbent layer. In addition, the thin fluffy pulp layer 315 closest to the liquid-permeable top sheet 301 may be omitted.

[0094] It should also be noted that the diaper, as used herein, is practically used in connection with incontinence, but the invention is not limited to this particular use and to any size and type of diaper associated with it, but may be any diaper. obvious to a specialist in the field.

Example 3 [0095] Figure 4a shows a hook fastening device (401) containing a carrier material, for example a non-woven spunbond, with a specific weight of about 25-60 g / m². The support material is preferably made of polypropylene fibers, but any conventional material can be used. The support material further includes a permanent magnet (402). The permanent magnet (402) is held in place by the hook material (403) that is directly attached to the carrier material by conventional hot melt adhesive. Optionally, the magnet can be attached directly to the support material. The hook material (403) holds the magnet in place so that the position of the magnet is always correlated with the position of the hook material.

[0096] Figure 4b shows a cross-sectional view along the line II for one embodiment of the hook fastening device.

[0097] Figure 5a discloses another embodiment of a fastening device. In this embodiment, the permanent magnet is free with respect to said hook material. I show it

A magnetoelastic film for a stronger primer field, which may be advantageous when the product is worn.

[0098] It should be noted that the hook material may be replaced by an adhesive film or any other fastening material known in the art. If the fastening system consists of a magnetic fastening device, such as used in pouches or the like, there is no need for an additional permanent magnet. Instead, a backing field from a magnetic fastening system may be used in the system according to the invention.

[0099] The permanent magnet, as shown, is rectangular in shape, but in other embodiments it may be in the form of small metal pieces of various shapes and sizes (such as those used at home as kitchen refrigeration appliances), powder, granules, foil, magnetic ink and other existing forms. The thickness of the magnet can also be in the range of about 30 μm - 5 mm, such as approx. 40 μm - 3 mm, 70 μm - 2 mm, 100 μm - 2 mm, 500 μm - 2 mm, 1 mm - 2 mm, 30 μm - 1 mm, 30 μm - 500 μm, 30 μm - 200 μm.

[0100] A "thin" magnet may have a thickness of about 40 Pm, while a typical "thick" magnet may have a thickness of about 1 mm. The length and width of the magnet are preferably adapted to each application. Typically, the magnet has at least one dimension, such as length, diameter or the like, at least 5 mm, 10 mm, 2-10 mm, 20 mm, 30 mm, 40 mm, 50 mm or about 10-20 mm, such as e.g. 10 - 30 mm, 10 - 40 mm, 10 - 50 mm, 10 - 100 mm. Different magnets provide different undercoat fields that affect the magnetoelastic film. In one embodiment, multiple permanent magnets may be used.

Example 4 [0101] An excitation device is used to excite a resonant object of an embodiment of the present invention. Said excitation device includes in one embodiment the excitation coil and corresponding circuits and a power supply for providing to said coil a signal suitable for generating the excitation field in radio frequency.

[0102] The reading device is used to receive a response signal emitted by a resonant object. Said reading device comprises in one embodiment a receiving coil and corresponding circuits and a power supply for receiving and acquiring frequency data from said response signal. Said reading device further includes a display for displaying said frequency. In a further embodiment, said reading device includes circuits or software for determining whether the frequency relates to a properly fastened absorbent article or to an unfastened / removed absorbent article.

EP 1 901 689 B1

Example 5 [0103] In a further embodiment of the present invention, said absorbent article is provided with sealing means. Said sealing means comprise a first part and a second part.

[0104] Said first part is provided with inflow means. Said second part is equipped with a resonant object, capable of being influenced by means of influence.

[0105] Said first part and said second part are adapted to be able to attach them to each other, i.e. the seal is closed, so that when they are attached, the influence means influence the resonance object. When they are disconnected from each other, i.e. when the seal is broken, the means of influence do not affect said resonance object to any significant degree.

[0106] Said sealing means are arranged on the absorbent article in such a way that when the absorbent article is correctly attached to the user and the sealing means are closed, it is not possible to remove or displace the absorbent article without breaking the seal. When the seal is broken, the response from the resonance object and the event can be detected.

Preferably, the means of influencing are provided in or on the adhesive tape, and when the absorbent article, e.g. the pants diaper, is correctly positioned, the adhesive tape is attached to the part containing the resonant object, thereby affecting the resonant object.

[0108] When the pants diaper is removed or displaced intentionally or unintentionally, the belt will be displaced from its position and the effect of the resonant object will be changed. The response from said object is therefore changed and the event can be detected.

EP 1 901 689 B1