DE1610547C3 - diaper - Google Patents

Description

45

The invention relates to a diaper, the absorbent pad of which is made up of a cover layer on one side thin porous, fibrous material is provided, which has an oily material application

One of the main causes of diaper chafing is that the skin becomes thick generally softens on the underside of the trunk as a result of prolonged contact with excreted fluid. In order to reduce the effect of prolonged contact of the liquid with the skin, have already been Diapers and diaper covers produced the part or surface thereof that comes into contact with the body partially or completely made of hydrophobic fibers, e.g. B. Polyacrylonitrile fibers or polyolefin fibers passed. The cover layer described is porous and allows that the liquid easily passes through them into an absorbent layer underneath and becomes preferably distributed in the hydrophilic layer, the hydrophobic cover layer or diaper insert stay relatively dry. A hydrophobic top layer behaves in the described way, however, depending on their layer thickness (and thus on the volume of what is under pressure in it free space). It is known that the pressure exerted on the diaper when it is used is frequent Liquid from the absorbent layer and through the open pores of the hydrophobic cover layer or Diaper insert presses, whereby the skin becomes moist again. The frequency of this rewetting increases as the absorbency of the locally moistened area of the absorbent layer increases is achieved. If this pumping speed is exceeded, the surface of the top layer or remains Diaper insert "flooded" until the moisture seeps through from the moister to the drier Areas of the absorbent layer the moisture concentration spreads further or until the compression pressure The result of continuous compression and subsides on the absorbent layer Decompression is therefore the repeated rewetting of the skin surface that occurs when the evaporation is not very fast, soaking up the liquid is hydrated and softened. As a result of Hydration of the horny layer of skin takes away the irritation of the skin itself towards materials, against which it is normally inert like olive oil, is essential too.

When the soreness shows up from rubbing the diaper on a child's skin, bring one often a protective layer (e.g. baby lotions, mineral oil or the like) on to further soften the skin prevent and allow the irritated area of skin to heal. This is usually done by pouring the oil or the lotion, for example, in one of the hands, rub both hands together to get the substance then rub it into the child's skin. This process is wasteful, unclean, easily forgotten and generally uncomfortable and unaesthetic.

For this reason, discontinuous surface films made of a protective material were also applied to the top layer from diapers that are intended for single use, applied to the separate application to avoid the protective layer by the parents at the time of the diaper change. In this way could an oily film in contact with the skin in its driest state on the child's skin applied and thereby a moisture-repellent layer can be maintained to avoid sores to prevent from the outset instead of only acting after the soreness has occurred. It did, however found that this proposal is ineffective with those diapers which do not have a hydrophobic cover sheet to have. In addition, it has been found that although disposable diapers with a hydrophobic cover layer are used a freshly applied moisture-repellent film on their hydrophobic top layer work well, that, however, after the product has aged, it is the only one in the normally expected storage time noticeable effect on the film was of an adverse nature, namely the reduction in usable capacity the diapers existed. It is believed that the moisture repellant material through the top layer migrates through into the absorbent pad located underneath. This increases the degree of absorption the absorbent layer that formed the cushion, reduced the ability of liquids to absorb moisture to let through from the moist central area into the drier edge areas of the diaper, and the

Distribution effect, through which the top layer between the wetting was kept relatively dry, also reduced

In a known disposable diaper, which consists of three groups of absorbent soft cellulose wadding layers consists, the upper, the body facing layer near its edge with an oily substance has been treated (the other two layers are each with an antiseptic and a deodorant Means treated), the top layer consists of an absorbent, i.e. H. hydrophilic and oleophilic material. However, the oily material applied to the top layer is only at the edge of the same and spreads towards the middle of the diaper, with the child's skin, but also at the same time the surface of the Cellulose wadding top layer is covered. Since it is an absorbent layer, the oily one penetrates Substance into this layer, so that the usable capacity of the absorbent layer, namely excretory liquid take up is reduced.

The present invention is therefore based on the object to provide a diaper in which the skin of the Child protected by an oily, moisture-repellent film and thus the possibility of Sore in the child through contact with urine and / or feces is reduced, but avoided will that

1. the oil inside, d. H. the absorbent part of the Diaper penetrates and

2. The oil appears as a continuous film on the Cover layer spreads or the cover layer wets and thus a penetration of the moist The child's excretions are prevented in the absorbent layer, so that the usability is fully preserved

This object is achieved in that the absorbent part of the diaper with a thin A cover layer made of fibrous material, the surface of which, i.e. the side facing the child, at least in the middle, the critical area, oleophobic and hydrophobic, i.e. oil- and water-repellent Has properties and on this surface a discontinuous film of an oily, moisture-repellent Material applied whose surface tension is greater than the surface tension of the oleophobic and hydrophobic area of the top layer - discontinuous, thus moisture can drain inwards, greater surface tension, so that the oily material does not move inwards penetrates and also with it the discontinuous state, which results from the greater surface tension and thus results in droplet formation, is maintained.

According to the invention, the diaper is designed in such a way that the fibers adhere to the middle area of the cover layer of the surface are hydrophobic and oleophobic and that the outer surface of said area of Layer is provided with a discontinuous, oily material-containing film, the critical The surface tension of the fibers is lower than that of the film.

An exemplary embodiment of the invention is described in more detail below with reference to the drawings. In this shows

F i g. 1 is a perspective top view of the cover layer of the diaper;

FIG. La shows a cross section through part of the diaper with the one shown in FIG. 1 top layer shown,

FIG. 2 shows an enlarged cross section through the fibers of the cover layer according to FIG. 1, wherein Droplets of the oily moisture-repellent material located thereon are shown, and

3 shows a vertical section through a part a device that is used to apply a moisture-repellent material to one side of the Top layer of a disposable diaper is suitable

ίο Fig.4 is a partial view of part of the Device according to FIG. 3 along lines 4-4.

The cover layer 10 shown in FIG. 1 can consist of any compliant, soft, porous web 12 that incorporates the hydrophobic and Has oleophobic properties. The dimensions of the web 12 are determined by those of the absorbent pad of the Diaper and determined by the diaper structure As FIG. 1a shows, the edges 12a of the web 12 can under the pad 11 folded and connected to the lower surface of the same by an adhesive, so that the exposed edges of the absorbent material, which is made from creped cellulose wadding or from an air-felt can exist, are enclosed. The underside of the pad 11 and cover layer 10 as a whole can with a Moisture-impermeable back 11a are connected. Along the central area of the web 12 and only on one side of the same is a discontinuous film 14 of an oily, moisture-repellent Material that will not irritate the child's skin and is non-toxic. Such materials can of mineral oils with different molecular weights and viscosities, for example medicinal White oils (e.g. liquid paraffin oil, U.S.P. XIV, and light liquid paraffin oil) and paraffin oil U.S.P. XIV

of animal oils (for example triglycerides of higher fatty acids such as stearic, palmitic and oleic acids, lanolin and cod liver oil) and of vegetable oils, e.g. B. soybean oil, peanut oil, cottonseed oil, rapeseed oil, olive oil, palm oil and coconut oil. The properties of the oily protective material can be improved and the possibility of penetration of the tissue further reduced if it is mixed with an additive capable of increasing its viscosity. For example, a low viscosity mineral oil can be combined with a crystalline material, e.g. B. the aforementioned triglycerides, or with inorganic materials, e.g. Zinc oxide, or with metal salts of fatty acids having 12 to 22 carbon atoms, such as calcium, magnesium, potassium or sodium salts of stearic and palmitic acid, to increase its viscosity for use from a moisture-repellent material. Such additives to these protective materials can be used in appropriate amounts depending on their effect on increasing the viscosity, but preferably in amounts of up to 10% by weight of the protective material.
Preferably, the protective material has a viscosity of about 70 to about 280S.US at about 38 ° C. Preferably, the discontinuous film 14 contains a plurality of individual droplets 14a (see FIG. 2) with diameters in order to avoid a greasy look and feel Ranges from about 0.05 to about 1.0 mm, and it is applied in amounts from about 0.00016 to about 0.0031 g / cm ^2. If it is desired to "grease" the skin, apply higher concentrations an increased content of oily

Materials.

The illustrated embodiment has the discontinuous film 14 along the transversely extending one central region of a surface of the web 12. However, the film 14 can also be along the central longitudinal part be arranged or extend over the entire surface. The film is useful a width of about 200 mm. The manner of applying the discontinuous film 14 to a continuous web 12 is described below.

An oleophobic and hydrophobic web 12 is understood to mean a web whose critical surface tension, in contrast to the surface tension of the oily moisture-repellent material and that of the excreted liquids, is sufficiently low can spread. In general, the angle of contact of these materials on web 12 (ie, the angle between the web and liquid interface and a line in a perpendicular plane tangent to the liquid and air interface and through a point on the periphery of the interface between Web and liquid passes) greater than 90 °, so that a distribution of the oily liquid on the fibers of the web 12 is prevented. The greater the difference between the critical surface tension of the web 12 and the surface tension of these materials, the greater the contact angle and thus the lower the possibility of wetting the web under pressure. The critical surface tension of the web 12 is intended at 20 ⁰ C for about 7 to 25dyn / cm, preferably less than about 20 dynes / cm and at least about 5 dynes / cm below the surface tension of oily moisture-repellent material, from which the discontinuous film 14 is The critical surface tension values given above relate to critical surface tensions of corresponding surface systems measured on a flat plane, since it is difficult, if not impossible, to accurately determine such values in the case of irregular or rough surfaces, e.g. B. in a tissue to measure. In the present case, the critical surface tension of a cover layer, the fibers of which z. B. are coated with a fluorine compound, correspond to that measured on a coating of such a compound on a smooth flat surface.

The web 12 can be made of any porous material, e.g. B. paper or a woven, knotted or non-woven structure. For example, the web 12 can be a nonwoven fabric composed of 1.5 to 3 denier rayon fibers 33 to 41 mm in length, containing about 10 to 35% binder (e.g., crosslinked polymers of ethyl acrylate) and weighing about Has 17.9 to 22.7 g / m ^2. In the manufacture of such a top layer, surfactants in the binder emulsion should be kept to a minimum and generally avoided in the saturation bath or in the immersion liquid. In this way, the preferred porous cover layer given in the examples is obtained.

The non-woven cover layer described as an example can be coated with a substance or capable of the critical surface tension of web 12, if not is low enough, d. H. does not correspond to the preferred limits given above. It any coating material capable of effecting this reduction can be used, and which has no adverse or irritating influence on the child's skin Treatment material can, for example, consist of fluorine compounds, silicones or waxy fat derivatives (e.g. a pyridinium acid chloride derivative of stearic acid amide). Because of the very low critical surface tension, which the fibers of a web by coating with or application of an oil and fluorine water-repellent compound can be imparted, such compounds are preferred Agents to be used with the web 12 treatment materials.

These preferred fluorine compounds can have very different chemical structures. For example, acrylates and methacrylates of hydroxy compounds which contain a strongly fluorinated radical, as well as their polymers and copolymers can be used. Other fluorine compounds that can be used are the chromium coordination complexes of saturated perfluoromonocarboxylic acids, e.g. B. the chromium complexes of perfluorobutyric acid and perfluorooctanoic acid. Further examples of suitable fluorine compounds are perfluorinated ethers, fluorocarbon acrylamides (fluorocarbon sulfonylacrylamides and methacrylamides) and their polymers, phosphorus-containing fluorocarbon compounds and their polymers, e.g. B. Perfluoroalkylsulfonamidoalkyl esters of phosphoric acids. Perfluoroalkanoic acids, e.g. B. perfluoro lauric acid (F ₃ C (CF ₂ ) IoCOOH) and compounds containing perfluoroalkyl carbamate chains linked by methylene bridges are known consists

The following examples illustrate the treatment of the web 12 of the present invention with compounds capable of imparting hydrophobic-oleophobic properties to the surfaces of the fibers. In any event, the treated topcoat obtained has a critical surface tension in the range of about 7 to 30 dynes / cm. According to the procedure described in the examples, a discontinuous film of an oily moisture-repellent material is applied to the central part of each cover layer in the manner described below, and the cover layer carrying the film is placed on the absorbent pad of individual droplets about 0.05 to 1.0 mm in diameter and has a cumulative weight per unit area of about 0.00016 to 0.0031 g / cm ² .

example 1

A sample of the porous cover layer described above is saturated with a 1% by weight solution of an N-methyl-N-perfluorooctanesulfonylacrylamide polymer in hexafluoroxylene as solvent and passed through nip rollers in order to remove excess solution. The topcoat is then dried for 10 minutes at 150 ⁰ C in an oven to give a treated top layer, the hydrophobic and oleophobic whereby individual droplets of discharged fluid and mineral oil, on the surface

are deposited on the web, remain behind or flow off, instead of spreading and wetting the surface. The top layer can also be in an aqueous Latex dispersion can be treated with the polymer.

Liquid paraffin oil USP XIV, with a droplet size of about 0.20 to 0.80 mm and an average weight of about 0.0016 g / cm ^{2, is} applied as an oily moisture-repellent material to the top layer. The unit consisting of the absorbent pad and the top layer retains its effect in a disposable diaper for at least several months after completion.

Substantially similar successful results have been obtained using the following water-repellent materials in place of the liquid paraffin oil described in the previous example, U.S.P. XIV, used were: lanolin, cod liver oil, triglycerides of stearic, palmitic and oleic acids, soybean oil, peanut oil, Cottonseed oil, rapeseed oil, olive oil, palm oil, and coconut oil.

Example 2

A sample of the porous cover layer described above is saturated with a 5% by weight solution of N, N'-methylene-di (methylene-bis-1,1-dihydroperfluorooctyl carbamate) in acetone, then dried and 3 minutes in an air-heated Oven heated to 150 ^{° C.} The treated top layer, on which about 4% by weight of the fluorine compound is deposited, is extremely hydrophobic and oleophobic.

A slightly liquid paraffin oil with a viscosity of 85 SUS at 38 ^° C., which contains 5% by weight (based on the paraffin oil) of sodium stearate as an additive, has been found to be very effective as a moisture repellant material and is extremely resistant to penetration of the treated fabric for considerable periods of time

By repeating the above example, similar successful results were obtained using the the following additives in amounts of from 0.5 to about 5% by weight of the moisture-repellent material instead Used by sodium stearate: zinc oxide, sodium palmitate and triglycerides of stearic, palmitic and oleic acid.

Example 3

Samples of the porous cover layer described above were coated with an emulsion of fluorocarbon polymers at polymer concentrations of 0.18, 0.46 and 0.5% by weight of the solution saturated thereby the fibers of the cover sheets were effective with the fluorocarbon in amounts of about 0.2-0.5 Weight percent solids based on the weight of the web coated. The top coats were then 10 minutes dried at 82 ° C. In experiments it was then found that they are all extremely hydrophobic and were oleophobic.

It was found that each of the top layers obtained in the above example was one critical Had surface tension of less than about 20 dynes / cm. As any of the oily ones listed in Example 2 Moisture-repellent materials were applied in the manner described, was the critical The surface tension of each of the cover layers of this example is at least about 5 dynes / cm less than that Surface tension of the moisture-repellent material. The moisture repellant material spread does not come off and also does not wet the surfaces of the top layer

Example 4

A 457 mm wide continuous sheet of the porous cover sheet described was covered with a Speed of 6.7 m / min, through a group of Out nip rollers, one of which was covered with a 203 mm wide felt, the 0.056 Wt.% Fluorocarbon polymer containing spray emulsion was saturated. The train was through this emulsion is saturated in a central area 203 mm wide, on a heating roller, which is filled with steam of about 146 ° C, dried and cut transversely to produce a variety of To obtain the above-mentioned, 368 mm wide and 457 mm long cover layers. In the 203 mm in the broad middle range, fluorocarbon polymers were found in an amount of about 0.23 weight percent solids, based on the dried web, deposited The web has been found to be suitable for the purposes of the present Invention was satisfactorily hydrophobic and oleophobic.

Example 5

The procedure of Example 4 was repeated that of 0.5 using an emulsion Was composed of fluorocarbon polymers by weight. The amount of in the 203 mm wide central area Solids deposited amounted to 2.13% by weight of the dried web. The one coated with the polymer Part of the cover layers made from the treated web were extremely hydrophobic and oleophobic and thus well suited for use according to the invention

Example 6
The following solution was made:

88.5 parts by weight of water;

7.5 parts by weight of an acrylic-based binder with a solids content of 45%;

4.0 parts by weight of an emulsion composed of 99% by weight of water and 1% by weight of a fluorocarbon polymer emulsion.

The solution was applied to a web of rayon fiber. The web was saturated and then expressed to remove excess moisture, and dried at 200 ° C for 30 minutes. The solids content of the fluorocarbon polymers in the Solution was 0.13% by weight and was 0.1% based on the total weight of the dry web. The web was a well bonded and extremely hydrophobic and oleophobic web. She was as Cover layer is well suited for the disposable diaper according to the invention

Example 7

A similar solution was prepared as in Example 6, except that 89.5 parts by weight of water and 3.0 parts by weight of the emulsion were used. After applying the emulsion to an unsolidified one Rayon fiber web and subsequent drying according to the procedure described above the dry web was found to have a solids content of about 0.05% by weight fluorocarbon

Has fabric polymers. Here, too, the web was well consolidated and possessed the hydrophobic and oleophobic Properties for use as a top layer according to the invention.

Example 8

A perfluoroalkylsulfonamidoalkyl ester of phosphoric acid was prepared as follows: 200 g of N-ethyl perfluorooctanesulfonamidoethyl alcohol is mixed with 100 ecm benzene and 150 ecm benzotrifluoride Then 40 g of pyridine and then 16.7 g of phosphorus oxytrichloride are added with stirring The mixture is refluxed for 16 hours, cooled and filtered. The residue is slurried with water, filtered and dried in vacuo at 60 ° C.

The phosphate obtained is applied in l ° / cent solution in acetone-methyl chloroform (10:90 wt .-%) by known methods as described porous coating layer The coating layer is dried for 10 minutes at 150 ⁰ C. It has been found that it as the top layer can be used well for disposable diapers.

Example 9

A chromium complex of perfluorinated lauric acid (CF ₃ (CF ₂ ) 6COOH) of the Werner type was obtained as follows:

2.59 parts by weight of the acid was in 51 parts by weight Isopropyl alcohol was then dissolved in a 34% strength by weight chromyl chloride solution in Brought carbon tetrachloride in an amount of 8.24 parts by weight under the surface of the alcohol solution The solution obtained has a chromium / acid ratio of 2.88 chromium atoms per acid molecule. the The rate of addition of the chromyl chloride solution to the alcoholic solution of the acid became so that regulates the temperature of the mixture at 43 ° C was held. After the addition of the chromyl chloride solution was completed, the reaction mixture became distilled to remove carbon tetrachloride. The amount of distillate removed was 19 parts by weight. The mixture was then cooled and washed with 0.26 parts by weight of water and 1.6 parts by weight of isopropyl alcohol added in order to obtain a solution with a solids content of 30% by weight. This 30 wt .-% solution was distilled by adding 3.3 volume units of the solid solution to 50 volume units Water diluted so that the total solids content was 1%. Then this Solution with 12.2 volume units of a 30% strength aqueous urea solution as a buffer and HCl rinsing agent The solution was then diluted to a total volume of 100 with distilled water

The 10% solution is applied to the cover layer described by known methods to achieve a moisture uptake resulting in a total solids content of about 0.6% by weight on the Top layer leads. Then it is cured for six minutes at 157 ° C. The cured sheet is thoroughly cured Washed with water to remove excess urea and then dried. The dried web is extremely hydrophobic and oleophobic.

Example 10

According to US Pat. No. 2,642,416, a 1,1-dihydroperfluorooctyl acrylate polymer is prepared and incorporated into an emulsion which contains the polymer in a concentration of about 1% by weight of the solution. The emulsion is converted to the porous one described above by known processes Top layer applied whereby the polymer is deposited thereon in amounts of about 0.6% by weight, based on the top layer. The top layer is then dried for 15 minutes at 77 ° C. The treated, dried web is hydrophobic and oleophobic and suitable for the application according to the invention
Another sample of the porous cover layer is in the same way with equal amounts of 1,1-dihydroperfluorooctyl methacrylate ie

CH ₂ : C (CH ₃ ) COOCH ₂ C ₇ Fi ₅ ,

In terms of the hydrophobic and oleophobic properties, an in similarly obtained a satisfactory result

Although the minimum amount of treatment material required to achieve the desired hydrophobic-oleophobic To produce properties in web 12, it was found that fluorine compounds varied are required in amounts of at least about 0.05 percent by weight of the web. The upper limit of the Amount of the fluorine compound can range up to about 10% by weight of the web, although it is comprised of For economic reasons it is preferred to limit the range to less than 2%.

FIG. 2 shows fibers 12a of a cover layer 12 which are completely coated with a material 13 so that the droplets 14a of the oily water-repellent material do not wet the surfaces of the fibers. The apparatus for applying the discontinuous film 14 of oily moisture repellant material is shown in FIGS. 3 and 4 explained According to FIGS. 3 and 4, a cylindrical sieve 16 rotates through a basin 17 filled with such a material and thus brings the material at a substantially constant speed to an application point A. The sieve 16 consists of a plurality of rings 18 which are coaxially arranged and spaced from one another and are covered with a wire mesh 20 with a mesh size of about 420 μ. Preferably the cross-section of the ring is as small as possible while still maintaining sufficient rigidity to hold the screen in a radial direction. The rings 18 are made of stainless steel and can have a radial thickness of about 3.2 mm when the outer diameter of the part 16 is about 305 mm. The rings 18 and the fabric 20 are unitary, for example spot-welded, as a result of which an integral whole is obtained with an axial length which corresponds to the desired width of the film 14

The basin 17 with the oily moisture-repellent material is located in a container 22. This Can be made of sheet metal, plastics or the like. It is high enough to absorb the moisture-repellent To enable material in the appropriate depth. The container 22 has a greater length than that Axial length of the screen 16 and such a width that the part of the periphery of the screen 16 can accommodate the should be rotated through it.

The screen 16 is freely supported on two similarly constructed drive rollers 24 which extend over the container 22 extend. The rollers each consist of a steel body 28, one at each end to the outside The length of the body 28 between the shoulders 28a is slightly greater than the length of the screen 16. The body is preferably lined with a layer 286 of elastomeric

Material or another oil-resistant substance covered In the axial bore is a shaft 30, which extends through body 28 and is held in place by set screws or studs. The shaft is rotatable and is supported by bearings (not shown) in holders 32 so that the rollers 24 are in position above of the container 22 are kept at a sufficient distance and it is possible for the screen 16 to be in reach a predetermined depth into the basin 17. For example, if it is desired that the screen 16 25 mm below the surface of the basin 17 and the diameter of the screen 16 and the rollers 24 305 or 70 mm, the axes of the rollers 24 can be 330 mm apart and 40 mm above the Be arranged liquid level of the basin 17. The rollers 24 are running at a constant speed driven by means of a drive device operating with a chain 26 and a toothed wheel 26a. The rotation of the Rolling 24 causes the screen 16 to rotate at approximately the same speed.

Within the screen 16, in the vicinity of the application point A, there is axially an air nozzle 34 with a slot which extends over the full length over the screen 16. The shape of the nozzle can be of any desired shape. In the illustrated embodiment, however, it consists of a body 36 with an essentially U-shaped cross-section, on whose bent legs adjustable nozzle plates 38 are seated. The adjustability of the plates makes it possible to bring the lips into the desired distance and to form the slot through which the speed and flow of the compressed air flowing through can be regulated. The adjustment can be made by a plurality of machine screws and slots 40 arranged at a distance from one another.

The ends of the nozzle plates 38 seated on the body 36 are secured by seals 42 made of elastic material locked. The end plates 44 are attached to the body 36 by machine screws or the like Threaded bolt 36a protrudes from an end plate 44. There is adjustable on it within a vertical slot 46a the nozzle 34 by means of a nut 366 in a bracket 46. A Air supply line 48 projects with a threaded bore at the other end of plate 44 in FIG Link. It establishes the connection between the interior of the nozzle 34 (through an opening in the abutting seal 42) and a compressed air source. The tube 48 sits on an adjustable Suspension device (not visible) whereby each side of the nozzle 34 is vertically adjustable

A continuous length of the hydrophobic-oleophobic treated web 12 of the desired width is placed on the wire 16, which moves at constant speed and passes the application point A. The web is fed by the tension rollers 50, only two of which are shown in the drawing , held and guided Devices for feeding, guiding and receiving such webs are already known and are therefore not described in detail. The same applies to a construction for holding the container 22, a chain drive drive motor or the like for driving the gears 26 and details of the holder 46, the holder 32 and other parts, their application and arrangement obvious to those skilled in the art lie.

As the screen 16 rotates, a film of the material from the bath 17 is picked up on the fabric 20 and directed to application site A. At this point, the airflow from the nozzle 34 blows the material from the wire fabric onto the adjacent surface of the web 12, as follows that the discontinuous film 14 is formed.

In the device described above and using an air nozzle with a slot with a Width of 0.13 mm when using a

ίο Mineral oil as an oily moisture-repellent agent, the air stream flowing out of the slot, the mineral oil film brought by the wire mesh 20 onto the web 12. The air nozzle is 6 mm below the height of the wire mesh 20 and operates with an air pressure of 0.21 to 0.49 kg / cm ² . The web 12 is located 254 mm above the wire mesh 20 at the point of application. The mineral oil is applied to the web 12 in the form of droplets having the above diameter ranges result, the desired continuous film 14 is obtained, which is about 0.00046 to 0.00092 g of mineral oil contains per cm ² and has such a width that is about the If more mineral oil is required per unit area, the speed of the screen 16 is increased in relation to the web 12 reduced

The velocity of the gas propelling the oily material at point A from the wire screen 20 to the web 12 should be sufficient to drive the droplets deep into or through the web 12 since, when the diaper is used, the deeply embedded droplets will not open up get into the child's skin. To this end, the gas velocity is regulated depending on the size range of the droplets, the porosity and depth of the web 12, the distance between the wire mesh 20 and the web 12, and similar sizes for the specific apparatus and materials used.

After the film 14 has been applied to the continuous web 12, the individual cover layers 10 are in the cut to the respective width. The cover layers 10 are then used as body-hugging parts of the disposable diapers and can be combined, for example, with the rest of a disposable diaper. Independent from the specific diaper shape, the cover layer is applied to one side of an absorbent pad,

so that the surface carrying the film 14 of oily moisture-repellent material is on the outside Production of a disposable diaper with a cover layer 10, the diaper is folded like a wallet in this way that the cover layer 10 is located inside the fold and only comes into contact with itself. This allows the disposable diapers to be stored for long periods of time without the film Peeling or oily moisture-repellent material migrates into the absorbent pad If the Diapers with the cover layer according to the invention are put on the child, the film reaches the Child's skin. It forms a barrier layer that insulates and protects the skin from softening Protects separated fluid and irritants that are present in the stool caught by the diaper could be. In this way, the possibility of the formation of sore spots in a child is reduced Diaper compared to other diapers that do not

wear the above-described top layer, significantly reduced on the other hand, under the same conditions of use it is possible in this way to increase the time between two diaper changes while the number of wound sites remains essentially constant

For this purpose 2 sheets of drawings

Claims (4)

Patent claims: 1. Diaper, the absorbent pad of which is provided on the one .Seite with a cover layer of thin porous fibrous material which has an oily material application, characterized in that in the central region of the cover ^- layer (10) the fibers on the surface are hydrophobic and are oleophobic and in that the outer surface of said region of the layer (10) is provided with a discontinuous film (14) containing oily material, the critical surface tension of the fibers being lower than that of the film (14). '5 2. Diaper according to claim 1, characterized in that the critical surface tension of the fibers in the area of the cover layer (10) at 2O ⁰ C is less than 25 dynes / cm and about 5 dynes / cm lower than that in the film (14) contained oily material, which is about 0.00016 to 0.0031 g / cm ² 3. Diaper according to claim 1 and 2, characterized in that the oily material of the film (14) to increase the viscosity triglycerides of stearic, palmitic or oleic acid, zinc oxide, calcium, Magnesium, potassium or sodium salts of fatty acids with 12 to 22 carbon atoms in the molecule or contains a mixture of these compounds 4. Diaper according to claim 1 to 3, characterized in that the hydrophobic and oleophobic Surfaces of the fibers have a coating consisting of an oil and water repellent Fluorine compound, preferably (a) acrylic and methacrylic acid esters of hydroxy compounds with a highly fluorinated radical or their polymers and copolymers, (b) chromium coordination complexes saturated perfluoromonocarboxylic acids, (c) perfluorinated ethers, (d) perfluoroalkanoic acids, (e) Fluorocarbonsulfonylacrylamides or methacrylamides or their polymers, (f) perfluoroalkylsulfamidoalkyl esters the phosphoric acids or (g) copolymers of perfluoroalkyl carbamates and methylene