CA2066694A1

CA2066694A1 - Water absorption bag

Info

Publication number: CA2066694A1
Application number: CA002066694A
Authority: CA
Inventors: Demetrio Leone; Carmine Pinti; Emiddio Bulla
Original assignee: Individual
Current assignee: ROYCE AG
Priority date: 1990-07-27
Filing date: 1991-05-06
Publication date: 1992-01-28
Also published as: FI921331A; JPH05501090A; WO1992002679A1; EP0494270A1; KR920702452A; BR9105819A; FI921331A0

Abstract

Abstract The water absorption bag (18) has an absorption pad (20) in which a superabsorber is homogeneously sprinkled into a pulp of cellulose fibres, and an absorption core (21) formed from at least one layer is made with a tear-resistant, liquid-permeable outer shell (22).

The cellulose fibres, preferably recycled fibres, are mixed with fibres of thermoplastic to form a homogeneous pulp in a weight ratio of at least 4:1, which pulp is shaped before or after three-dimensional homogeneous sprinkling of the superabsorber and is subjected to a heat treatment partially melting the plastic to bind the fibres at many points. The cellulose and plastic fibres joined like a net thus have an increased but resilient dimensional stability. The outer shell (22) may be designed to be openable.

The absorption pad (20) and/or the outer shell (22) preferably comprise integrated means for accommodating an insert (42) increasing the specific weight separately from the pulp with the superabsorber. The outer shell advantageously consists of natural fibres, preferably of sisal or jute fibres.

The water absorption bags (18) serve to protect against effects of water during fire, flooding, pipe leaks and the like.

(Figure 6)

Description

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Water absorption bag The invention relates to a process for producing a water absorption bag having an absorption pad in which a superabsorber is homogeneously sprinkled into a pulp of cellulose fibres, and an absorption core formed from at least one layer is made with a tear-resistant, liquid-permeable outer shell, a moulding being formed by the absorption of water. The invention also relates to a water absorption bag produced by the process.

With regard to the weight, storage and transport volume of the sand bags conventionally used for water breaches, European application 0 368 107 proposes using at least one absorption pad having a shell which consists at least in some regions of water-permeable material which is even tear-resistant in the wet state. This shell should form an expandable, closed interior containing a super-absorbent ma~erial. Compared to sand bags this solution provides the considerable advantage that small storage volumes and weights are adequate to be able to install water protection devices in sufficient quantity at the place of use which can be used to form dams and for binding water. The pulverulent superabsorbent material is sprinkled on nonwoven sheets arranged in the interior of the shell and which have been provided previously with an adhesive. Instead of insert sheets, the interior of the envelope may be divided by folds which are also covered with a superabsorbent material. Tube-like outer shells in European application 0 368 107 are divided into chambers.
For higher water levels the protective device may be made to have a greater specific weight by adding weights or by admixing quartæ sand and the like.

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As mentioned, the protective device according to European application 0 368 107 provides considerable advantages compared to conventional sand bags, both with regard to weight and also to storage and transport capacities.

It has been proved that the water absorption bags containing a gel-like, flowable composition and fully soaked with water are deformed in a pear-shape with respect to the cross-section when carried vertically.
This effect is probably weakened using insert sheets and folds, but cannot be prevented in principle.

The inventors have set themselves the task of providing a process for producing light or loadable water absorption bags, in particular for water defence, which have a greater dimensional stability with a tear-resistant outer shell while having a very high absorption capacity for water, can be produced cost-effectively and can be used universally.

With regard to the process the task is achieved in accordance with the invention in that the cellulose fibres are mixed to form a homogeneous pulp in a weight ratio of at least 4:1 with fibres of thermoplastic, which pulp is shaped before or after three-dimensional homogeneous sprinkling of the superabsorber and is subjected to a heat treatment partially melting the plastic to bind the fibres at many points, as a result of which the cellulose and plastic fibres joined like a net have an increased but resilient dimensional stability.
Special embodiments and further developments are the object of dependent patent claims.

A manageable water absorption bag which is light before use and has a superabsorbent absorption pad is provided using the process of the invention, and it not only 3 2~;~r,'~:~9~

protects against the effect of water by acting as a dam, but it also takes up and absorbs any water present.

Wherever and whenever water is not desirable, the water absorption bag absorbs it extremely rapidly: a light absorption pad can take up a multiple of its own weight of water in a few seconds.

Superabsorbers are highly absorbent polymers which can bind a multiple of their weight of water and thus form a gel which remains chemically stable even under the action of pressure. For small grains the total surface area of the superabsorber is greater and therefore absorption or gel formation takes place considerably more quickly. The adjusting of the absorbability of an absorption layer is also achieved using superabsorbers of different nature and/or different amounts of superabsorbers.

The following products are used for example as superabsorbers:

Aridall 1125 from Chemdal, U.S.A.
Drytech 510 from Dow Chemical, U.S.A.
PR 9910 S from Floerger, U.S.A.
FAVOUR 922 SK from Stockhausen, FRG.

Although the water absorption bags may be relatively large and the absorption pads may be designed to have one or more compartments, no insert sheets or folds are necessary to ensure the stability when removing the fully soaked bags, owing to the dimensional stability increased by thermobonding.

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The use of favourably priced cellulose fibres is of particular significance in view o the relatively large dimensions of the absorption pads in the water absorption bags. By making fibres from recycled material, in particular from paper and/or cotton textiles, using a hammer mill, cellulose fibres may be used after cleaning which burden the production budget with only 20 to 30 of the usual costs for cellulose fibres from new materials. The water defence bags of the invention for absorbing water are therefore produced wherever possible from recycled fibres and plastic fibres which are preferably mixed in a weight ratio of 5:1 to 100:1. Very good results have been obtained using a proportion of about 6 wt.% of plastic fibres, corresponding to a mixing ratio of about (16-17):1.

The plastic fibres are advantageously treated with a wetting agent before mixing in with the cellulose-containing fibres, in particular recycled fibres. This surface-active agent reduces the surface tension of water and this facilitates the penetration thereof into the absorption pad and accelerates the distribution of the liquid on the surface of the plastic fibres. The wetting agents to be used are known to the expert, an example which may be mentioned is the product "TRITON X-100" from Messrs. DUPONT.

The thermoplastic fibres mixed with the cellulose fibres are preferably fibrillated and consist of a polyolefin or a polyester. These usually have a diameter of 1 to 40 ~m, in particular 5 to 20 ~m.

It has proved to be particularly advantageous to mix cellulose-containing fibres with fibrillated polyethylene of high density. A product from Messrs. DUPONT known under the trade name "PULPLUS" consists for example of fine fibrils 1 to 20 ~m thick and about 1 mm long which form numerous connecting points with the cellulose fibres during heat treatment (thermobonding) if they are partially melted. In addition to the very small diameter, these plastic fibres have, inter alia, the following advantageous properties:

- high strength and orientation - easily processed and melted - high specific surface area - chemically inert - environmentally friendly - favourably priced.

The amount of superabsorber mixed into the pulp is 5 to 50, in particular 30 to 50 wt.%, based on the cellulose fibres.

The heat treatment for point-like melt adhesion of the fibres is preferably carried out at a temperature lying just below the combustion temperature of cellulose, preferably 160 to 220C, in particular 200 to 220C. The heat is transferred by contacting the final mixed pulp with at least one hot surface or a hot air stream.
Examples of suitable hot surfaces are a heating bed, a heating roller o:r a moving continuous heating belt. The transfer of heat takes place in each case for only a short time so that only partial melting takes place, not complete melting of the plastic fibrils.

At least the feed opening in the outer shell is preferably sealed so it can be opened and closed.

A used water absorption bag may be opened without difficulty and without any tools and the contents removed thanks to this design.

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The contents may be separated into their components, if they include inserts. Reuseable parts are dried, assembled to form water absorption bags which can be used again, with addition of new components if applicable, and sealed so they can be opened and closed.

Separable water absorption bags permit more simple and more rapid drying and ensure a virtually as-new quality of reused material.

Although only one longitudinal or narrow side of a water absorption bag has to be sealed so as to be openable and closeable, in this case reference is made to a feed opening, further longitudinal and/or narrow sides may also be sealed so as to be openable.

An outer shell is advantageously simply folded before or after adding the contents of the bag for sealing, unless it is for e~ample circular-knitted, and sealed so as to be openable and closeable on at least one side.

According to a first variant, the outer shell of a water absorption bag is sealed with one or more lateral openable sealing seams. Sides of the water absorption bag not provided with such a sealing seam have been previously sewn in conventional manner so they cannot be opened.

According to a second variant, the outer shell of a water absorption bag is sealed so as to be openable with at least one peelable adhesive tape or by means of at least one hem releasably adhered to one another. If need be sides which are not adhered are sewn so they cannot be opened.

According to a further variant, the three-sided releasably sea]ed outer shell of a water absorption bag 9 ~

is folded to form a collar in the region of the feed opening and releasably bound with a cord, as is conventional for potato sacks. The method which is very simple particularly in manual operation also facilitates the carrying of the bags by hand.

According to a final variant, the outer shell may be sealed with at least one removable hem.

Compared to the previous process, this one has the disadvantage that a piece of the outer shell is lost on each opening and the latter becomes smaller. A removable strip is consequently only used for simple, cheap outer shells which are disposed of after being used two to three times.

With regard to a loadable water absorption bag produced by the process mentioned above, the task is achieved according to the invention in that the absorption pad and/or the envelope comprises integrated means for accommodating an insert increasing the specific weight separately from the pulp with the superabsorber. Special embodiments and further developments are the object of dependent patent claims.

The insert ensures that the water absorption bag cannot float and that the specific weight is clearly above that of water.

The solution according to the invention thus relates neither to optimum absorption of interfering sand mixed into the pulp, nor must weights or the like be suspended or attached in a certain manner. Integrated means for accommodating an insert have neither the one nor the other disadvantage, they are safe to operate and simple to handle, while fully retaining the rapid and high absorption capacity of a water absorption bag produced by 8 2~ 9~

the process of the invention without the product features of the invention.

According to a first variant, sealed pockets formed in the outer shell contain a water-insoluble bulk material having a higher specific weight than water. Conventional fine-grain sand has proved to be particularly favourable.
Quartz sand, used sand-jet sand and the like may also be used advantageously. Mouldings enveloped in the pockets would be feasible but less advantageous than bulk material.

According to a second variant, the absorption pad may contain at least one flexible insert, preferably divided in one direction, with a water-insoluble bulk material having a higher specific weight than water. The inserts arranged in the absorption pad are preferably corrugated layers sealed on the end-face side with covering layers on both sides. For several corrugated layers an intermediate sheet is advantageously arranged between each one. Although mouldings can in turn also be used here, it is less advantageous than bulk material of the composition mentioned above.

The corrugated layers advantageously consist of at least one corrugated board of conventional construction which may also consist of paper. The corrugated board may have or be coated with an external hydrophobic layer so that it does not crumble when water is absorbed. Instead of board or paper, "corrugated board" may also consist of plastic films, advantageously with a perforation or with slots for facilitating the passage of water.

Corrugated boards filled with sand are produced by filling the end-face side openings of one side with a size or melt adhesive and compressing. Sand is then 9 21 . _~ 3~ ~

added, the other side is provided with a size or melt adhesive and likewise compressed.

The inserts in an absorption pad filled with bulk material, in particular corrugated board filled with sand, stabilise a water absorption bag filled with water.
The fullness cannot be too great, absorption pads with separate adsorption cores have greater stability.

The outer shell tear-resistant even in the wet state may have devices for carrying and/or fastening, which are integrated in the outer shell or attached to it, in a manner known per se or described below. Hence, the pads fully soaked with water may be collected without difficulty after use and stored at a designated place.

With regard to a tear-resistant water absorption bag produced by the process of the invention, the task is achieved in that the outer shell consists of a fabric, net, knitted fabric or nonwoven made of natural fibres.

Sisal or jute fibres are particularly suitable for a tear-resistant, not only water-permeable but also air-permeable outer shell. Also these fibres are cheap, resistant to wear and slip. The latter property has considerable importance particularly when stacking water absorption stacks one on another. Slip-resistant coatings and the like are thus not required even for greater static and/or dynamic water pressure. The geometric shape of the water absorption bags may have any form. Blocks designed to be approximately cuboid in a manner known per se, called "Water Blocks" in the technical terminology, which may also have inserts to increase the weight, are particularly practical.

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According to one particular embodiment of the invention, an insert for increasing the speciEic weight consists of an inner shell made from a fabric, net, knitted fabric or nonwoven made of natural fibres, preferably of sisal or jute fibres, is thus designed to correspond to the outer shell. The inserts may be provided with longitudinal and/or transverse divisions, as a result of which slipping of the contents, for example of the sand or of a non-rusting moulding without sharp edges or corners, is prevented. Mouldings are, for example rod irons bent like a serpent, grids, perforated and/or slotted sheets, all preferably galvanised.

The absorption pad is divided into at least two absorption cores as a result of the arrangement of at least one inner shell with one insert. These shells are not water barriers, they have good water permeability and also good air permeability.

All plastics used in water absorption bags of the invention preferably consist exclusively of non-halogenated hydrocarbon compounds and can therefore be combusted without residue. In the process the primary concern must be for any pollutants originating from the absorbed water.

In summary the absorption bags of the invention have the following advantages:

- whenever and wherever water is not desirable, it may be soaked up by converting the absorption pad within seconds into a moulding which collects quenching water.

- in cases of fire the water absorption bays are suitable for the protection of buildings and environment from damage by quenching water. The absorbed liquid is held $~

back for days. Hence, quenching water contaminated with pollutants is kept under strict control. The water collected and absorbed by absorption pads may be analysed so that the disposal can be carried out expertly.

- in cases of other disturbances, such as pipe leaks or flooding, in which amounts of flowing water become a problem, water absorption bags of the invention are a valuable aid which makes it possible for the helpers to use it immediately and assists their work simply, effectively and to lasting effect.

- for surface fires in the open air, water absorption bags may be laid out and wetted, hence they form an effective barrier against spreading fire.

- for the absorption of uncontaminated water, used water absorption bags may be removed without difficulty. They do not contain any environmentally harmful components.
Obviously they may also be dried and re-used. A fur-ther possibility for disposal consists in using used water absorption bags as such or divided up as moisture stores for the ground.

Basically there are two different types of water absorption bags:

1. Water absorption bags provided with a loading insert, for example have external dimensions of 600 x 350 x 18 mm and weigh approximately 2.5 kg. These water absorption bags cannot float because of their relatively large weight, they sink immediately in water. On the other hand, the bags may be stacked easily and they immediately form effective water barriers because of their essentially cuboid shape, even on an uneven base. A heavy absorption bag absorbs approximately ten times its own weight of water.

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In addition to the general uses of water absorption bags mentioned above, the heavy embodiment is particularly suitable for water barriers in excavations, garages, shopping centres, hospitals, storage depots, underground stations, subways and the like.

2. Light water absorption bags are used, for example in dimensions of 600 x 350 x 12 mm having a weight of approximately 500 g. They do not contain a loading insert. These water absorption bags are light and can be used everywhere thanks to their flexibility. These light water absorption bags can absorb approximately 50 times their own dry weight of water.

Although light water absorption bags may be used everywhere in principle, they are particularly suitable for sealing cracks and holes, alone or together with heavy absorption bags, for mopping up water in cellars, on balconies, terraces and roof breaches, and for absorbing overflow water from washing machines, bathtubs and the like.

The invention is illustrated in more detail using exemplary embodiments shown in the drawing which are also the object of dependent patent claims.

- Figure 1 shows schematically a section of the pulp of an absorption core, - Figure 2 shows schematically a cross-section through a dry, light water absorption bag, - Figure 3 shows schematically the full water absorption bag according to Figure 2, - Figure 4 shows schematically a view of a loaded water absorption hag with external pockets, - Figure 5 shows schematica]ly a cross-section V-V
according to Figure 4, 59 ~

- Figure 6 shows schematically a partial cross-section through a water absorption bag with internal weight, - Figure 7 shows schematically a partial cross-section through a water absorption bag with several internal weights, - Figure 8 shows schematically a variant of Figure 7, - Figure 9 shows schematically a cross-section through a sand-filled corrugated board, - Figure 10 shows schematically a longitudinal section through the corrugated board according to Figure 9, - Figure 11 shows schematically a partial plan view of a water absorption bag having an outer shell of plastic fibres, - Figure 12 shows schematically an unfolded, perspective view of a water absorption bag with an insert, - Figure 13 shows schematically a water absorption bag having three lateral sealing seams, - Figure 14 shows schematically a water absorption bag sealed with an openable seam, - Figure 15 shows schematically a folded inner shell, - Figure 16 shows schematically an inner shell according to Figure 15 divided by longitudinal seams, - Figure 17 shows schematically an insert according to Figure 16 partially filled with sand, and - Figures 18-21 show schematically further opening and closing seals.

The greatly simplified view of the basic structure of the pulp P of an absorption core reduced to two dimensions, as it appears in absorption pad 20 (Figure 2 ff.), shows a basic structure of cellulose fibres lQ. These are joined to one another via fibres 12 of a thermoplastic, shown as polyethylene fibrils. The plastic fibres 12 partially melted in a heat treatment process form numerous connecting points 14 with the cellulose fibres 10. The thermobonded structure leads to an increased but ,r~39 '~

resilient dimensional stability for the absorption core.
Grains of a superabsorber 16 are sprinkled to be homogeneously dispersed in the fibre structure.

The basic structure shown in Figure 1 may absorb up to about 50 times its own weight of water, a gel-like composition of high re-tention capacity for the water being formed. The dimensional stability is retained due to the thermobonding.

The dry, light water absorption bag 18 shown in Figure Z
comprises an absorption pad 20 having an absorption core according to Figure 1 and a flexible, tear-resistant outer shell 22. This is joined on both sides using a melt adhesive 24 to form an edge. The outer shell 22 may of course also be joined using a size.

A water absorption bag according to Figure 2 weighs, for example 400 g and has a length of about 0.8 m and a width of about 0.3 m.

The full water absorption bag 18 shown in Figure 3 lies on a base 26. It has absorbed somewhat more than 20 kg of water, that is more than 50 times its own weight. The water absorption bag 18 restrains a collected water layer 28 of low height.

The absorption pad 20 of Figure 3 is shown with a single layer design. Absorption pad 20 and absorption core are identical in the present case. However, the absorption pad 20 may also consist of several layers lying one above another.

The heavy water absorption bag 18 shown in Figure 4 has pockets 30 sewn or adhered on both sides of its outer 9 ~

shell 22 which are filled with sand 32, as can be seen in Figure 5. The specific weight of the water absorption bag 18 is thus increased so that there is adequate bearing pressure even when the water level in increased.

Handles 36, which facilitate carrying of the full water absorption bag 18, are cut out from the upper edge 34 in the region where the outer shell 22 is connected.

Eyes 40, which serve for any attachment or joining of several water absorption bags 18, are formed in the narrower lower edge 38.

The water absorption bag 18 shown in Figure 6 comprises an absorption pad 20 with an insert 42 arranged to float in the central region and which consists of three corrugated layers with covering and intermediate sheets.
This insert is filled with fine-grain sand 32, as shown below in detail, and thus increases the specific weight of the water absorption bag 18. The stabilising function of the insert 42 has already been mentioned.

The largely divided absorption pad 20 having two absorption cores 21 is surrounded by an outer shell 22 which forms a hem 25 using a melt adhesive 24. Dashed lines indicate that the floating insert 42 could also be attached in this hem. The hem may also be formed using an adhesive or sewn.

In the embodiment according to Figure 7, an absorption pad 20 of a water absorption bag 18 is divided by three inserts 42 each made from a corrugated board with sand 32, as a result of which four absorption cores 21 are formed.

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Figure 8 shows a water absorption bag 18 with an absorption pad 20 which is divided into three absorption cores 21 by two inserts 42 which each comprise two corrugated boards with added sand 32.

The inserts 42 have continuous perforations 41, for example in the form of holes or slots. These ensure improved passage of moisture from absorption core 21 to absorption core 21.

Figures 7 and 8 show examples of individual and groups of inserts 42 arranged to alternate with absorption cores 21, which inserts 42 serve to increase the specific weight of a water absorption bag.

Figures 9 and 10 show a corrugated board 44 filled with fine-grain sand 32. The lower and the upper covering layer 46, 48 each have an external hydrophobic coating 50. The corrugated layer 52 extending sinusoidally divides the corrugated board 44 into longitudinally extending chambers filled with the sand 32.

The longitudinally extending chambers are sealed on the end-face side by compressing them and sealing with a melt adhesive 24.

The corrugated layer 52 may extend, for example like a rectangle, trapezium or saw-tooth, according to embodiments not shown.

Anti-slip coatings 54 and perforations 55 extending like a serpent for the passage of air are arranged in the partial view of the outer shell 22 shown in Figure 11.

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Dry water absorption bags 18 filling with water and laid next to and one upon another are wedged into one another and thus offer a good hold against the static pressure and any dynamic pressure of the water. The anti-slip coatings 54 serve to improve this effect.

The anti-slip coatings may assume any geometric shape, for example straight lines, points, rings and the like, instead of a serpentine line.

A tear-resistant outer shell consisting, for example of a nonwoven, has very good water permeability, but can form a barrier to air. Perforations 56 are therefore stamped out or burned out from the outer shell 22. These have, for example a diameter of 1 mm and are arranged at intervals of 5 to 10 mm.

Figure 12 shows two halves of an outer shell 22 made from a jute net joined to one another via a seam 58. According to a preferred variant, the seam 58 or 62 is designed as an enveloping fold (Figure 15). An insert 42 with an inner shell 43 likewise consisting of bag material is also sewn into this seam 58. The inner shell 43 is divided by means of longitudinal seams 60 extending parallel to the seam 58. The spaces in the inner shell 43 are filled with sand 32 and act as a water-permeable and air-permeable heavy layer. Of course individual or, for example every second interior space formed by longitudinal seams 60 may be empty, that is not filled with sand 32. Furthermore, sand 32 may be replaced by galvanised rods. Absorption cores 21, which form the absorption pad 20, may be placed between the two parts of the outer shell 22 and the inner shell 43.

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According to further variants, several inner shells 43 may be arranged in an outer shell 22, in each case with absorption cores 21 lying therebetween. Furthermore, the inner shells 43 may be arranged to float (Figure 6), instead of being attached in a seam 58.

A water absorption bag 18 according to Figure 13 which looks rectangular is joined on three sides by seams 58, 62 and 64 via the outer shell 22. No seam is formed on the broad side opposite the seam 64, here there is the feed opening 66 in the outer shell 22 which is sealed so as to be openable.

Figure 14 indicates how the feed opening 66 may be sealed. An opening seal 70, also called sealing opening seam, sealing the water absorption bag 18 is formed using a tear-resistant thread 68.

Figures 15-17 illustrate in more detail the production of an insert 42 with inner shell 43 and contents. Initially a rectangular cloth made from bag jute is folded longitudinally down the centre (Figure 15).

The longitudinal seams 60 of the inner shell 43 shown in Flgure 16 extend parallel to fold 72. Corresponding strips of an adhesive may also be applied analogously to the longitudinal seams 60. After compressing the two halves of the inner shell 43, essentially tube-like chambers also extending parallel to the fold 72 would be produced to receive bulk material or a moulding.

Figure 17 shows the filling of an inner shell 43 with sand 32 as contents, which are introduced into the chambers limited by the longitudinal seams 60 via a movable and tippable metering device 74.

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The lnner shell ~3 shown in Figure 17 is sealed at the bottom using a non-openable sealing seam 64. Two transverse seams 76, which limit the length of the chambers formed by the longitudinal seams 60, are incorporated extending parallel to the sealing seam 64.

After adding the sand 32, the feed openings 66 are sealed with an opening seam 65 shown as a dashed line. Of course the transverse seams 76 may also be designed to be openable or may be omitted.

Figures 18-21 show openable and closable seals in the outer shell 22 which are not designed as an opening seam formed using a thread 68 (Figure 14).

According to Figure 18, one end 78 of the outer shell 22 is enveloped in the direction of the other end 80. An adhesive tape 84, which is peeled off when opening the outer shell 22 o~ the water absorption bag 18, is applied via both ends 78, 80 by means of an adhesive 82 which can be released with the use of force.

According to Figure 19, the two ends 78, 80 of the outer shell 22 are joined to one another by means of an adhesive 82 which can be released with the use of force, but wherein the outermost ends 78, 80 are free to grip and peel apart.

Figure 20 shows a feed opening in the outer shell 22 of a water absorption bag sealed like a bag of potatoes. The outer shell 22 is folded to form a collar 86 and bound using a tightly drawn cord 88.

Figure 21 shows the two ends of an outer shell 22 joined using a non-releasable adhesive 89. Weakened points 90 are stamped in the plane A. The adhered hem 92 may be removed as a whole and hence the outer shell opened.

Claims

Patent claims

1. Process for producing a flexible water absorption bag (18) having an absorption pad (20) in which a superabsorber (16) is homogeneously sprinkled into a pulp (P) of cellulose fibres (10), and an absorption core (21) formed from at least one layer is made with a tear-resistant, liquid-permeable outer shell (22), a moulding being formed by the absorption of water, characterised in that the cellulose fibres (10) are mixed to form a homogeneous pulp (P) in a weight ratio of at least 4:1 with fibres (12) of thermoplastic, which pulp (P) is shaped before or after three-dimensional homogeneous sprinkling of the superabsorber (16) and is subjected to a heat treatment partially melting the plastic to bind the fibres (10, 12) at many points (14), as a result of which the cellulose (10) and plastic fibres (12) joined like a net have an increased but resilient dimensional stability.

2. Process according to claim 1, characterised in that the cellulose fibres (10) are mixed with thermoplastic fibres (12), which are preferably treated with a wetting agent, in a weight ratio of 5:1 to 100:1.

3. Process according to claim l or 2, characterised in that the cellulose fibres (10) are mixed with fibrillated thermoplastic fibres (12), preferably of a polyolefin or a polyester, and treated with 5 to 50 wt.%, in particular 30 to 50 wt.%, of the superabsorber (16) based on the cellulose fibres (10).

4. Process according to one of claims l to 3, characterised in that cellulose fibres (10) obtained at least partially from recycled material, in particular from paper and/or cotton textiles, by making into fibres and cleaning, are used.

5. Process according to one of claims 1 to 4, characterised in that the heat treatment is carried out at a temperature lying just below the combustion temperature of cellulose, preferably 160 to 220°C.

6. Process according to one of claims 1 to 5, characterised in that at least the feed opening (66) of the outer shell (22) is sealed so it can be opened and closed.

7. Process according to claim 6, characterised in that the outer shell (22) is sealed with non-openable lateral sealing seams (58, 62, 64) and an openable seam (70), with a peelable adhesive tape (84), with ends (78, 80) of the outer shell (22) releasably adhered to one another, or with a removable hem (92).

8. Process according to claim 6, characterised in that the feed opening (66) of the outer shell (22) is folded to form a collar (86) and is bound with a cord (88).

9. Water absorption bag produced by the process according to one of claims 1 to 8, characterised in that the absorption pad (20) and/or the outer shell (22) comprise integrated means for accommodating an insert (42) increasing the specific weight separately from the pulp (P) with the superabsorber (16).

10. Water absorption bag according to claim 9, characterised in that sealed pockets (30) formed in the outer shell (22) contain a water-insoluble hulk material, preferably sand (32).

11. Water absorption bag according to claim 9 or 10, characterised in that the absorption pad (20) contains at least one flexible insert (42), preferably divided in one direction, with a water-insoluble bulk material, preferably sand.

12. Water absorption bag according to claim 11, characterised in that the divided inserts (42) are corrugated layers sealed on the end-face side with covering sheets on both sides and preferably intermediate sheets.

13. Water absorption bag according to claim 11 or 12, characterised in that the inserts (42) are arranged individually or in groups alternating with absorption cores (21), also so as to float.

14. Water absorption bag produced by the process according to one of claims 1 to 8, characterised in that the outer shell (22) consists of a fabric, net, knitted fabric or nonwoven made of natural fibres.

15. Water absorption bag according to one of claims 9 to 14, characterised in that the outer shell (22) consists of sisal or jute fibres.

16. Water absorption bag according to one of claims 9 to 15 which comprises integrated insert(s) (42) separated from the pulp (P) with the superabsorber (16) for increasing the specific weight, characterised in that the insert(s) (42) comprise(s) an inner shell (43) made from a fabric, net, knitted fabric or nonwoven made of natural fibres, preferably of sisal or jute fibres.

17. Water absorption bag according to claim 16, characterised in that the inner shell (43) is divided into receiving chambers for bulk material, preferably sand (32), sealable on the end-face side and separated by longitudinal seams (60) or longitudinal adhesions, or mouldings, preferably non-rusting rod iron or stamped steel sheets, without sharp edges or corners.

18. Water absorption bag according to claim 17, characterised in that at least one end-face side closure of the inner shell (43) can be opened.

19. Water absorption bag according to claim 17 or 18, characterised in that the inner shell (43) is folded centrally and preferably at least one transverse seam (76) or transverse adhesion extending vertically to the fold (72) and the longitudinal seams (60) is added.