EP3988004A1 - Cleaning sponge and method for the production of same - Google Patents

Abstract

The invention relates to a cleaning sponge (1) having a carrier body (2) made of a foam material, which has two opposite main surfaces (2', 2"), and a coating (3) on at least one of the main surfaces of the carrier body. The coating (3 ) consists of a composition comprising polyurethane and dispersed therein abrasive or non-abrasive particles (4) The non-abrasive particles are selected from the group consisting of precipitated silica, river sand, desert sand, walnut shell powder and mixtures thereof and have a size in the range of 20 µm to 1000 µm The abrasive particles are selected from the group consisting of pumice particles, silica sand particles, glass particles, corundum particles, calcined bauxite particles and mixtures thereof and have a size in the range of 20 µm to 1000 µm. The invention also relates to a method of manufacturing the cleaning sponges.

Description

The invention relates to a cleaning sponge with a carrier body made of a foam material and with a coating on at least one of the main surfaces of the carrier body, as well as a method for producing the cleaning sponge. The cleaning sponge is particularly suitable for cleaning tableware and cookware, but also for cleaning any other surfaces in the kitchen and bathroom, for example.

Cleaning sponges typically consist of a base body made of foam material, which serves as a carrier for a coating, the coating being the actual cleaning component. The coating should also be able to remove heavy soiling, such as dried-on encrusted food residue, but should also not scratch sensitive surfaces such as Teflon-coated surfaces.

Cleaning sponges that clean relatively gently are commercially available. They consist of a carrier body made of polyurethane foam with a polyurethane coating containing plastic particles, such as high-density polyethylene or polypropylene. When pressure is applied, the particles are pushed into the dirt and can damage it, making it more accessible to a cleaning liquid. The plastic particles are comparatively soft, so there is no risk of scratching the surfaces during cleaning on most surfaces to be cleaned. The cleaning effect can be supported by a three-dimensional surface finish of the cleaning surface, ie the cleaning surface has alternately raised and lowered areas. Cleaning sponges with fleece layers made of plastic fibers are also known.

A disadvantage of the known cleaning sponges is that plastic particles from the coating or plastic fibers from the non-woven material become detached as a result of the action of mechanical forces such as occur when the cleaning sponge is used. In the course of the service life of a sponge, the mechanical loads during cleaning cause a certain amount of wear and tear on the coating or the fleece, which means that as the cleaning sponge ages, more and more plastic particles are detached from the coating or plastic fibers from the fleece and in the form of so-called " Microplastics" get into the cleaning liquid used, for example the rinsing water when washing dishes. The cleaning liquid, in turn, is usually fed into the sewage system and, together with other waste water, reaches sewage treatment plants, where the microplastics cause considerable problems. It cannot be removed from the wastewater, or only with great effort, using special filters. In most sewage treatment plants, the microplastic cannot be removed at all, which means it gets into the drinking water and thus ultimately into the bodies of humans and animals, where it can have harmful effects on health. So far, it is still completely unclear what exact consequences microplastics can have for people, animals and the environment. What is certain, however, is that microplastics in seawater lead to physiological disorders, increased tumor formation and an increased mortality rate in marine animals. In this respect, it is to be feared that microplastics can also harm people.

There is no doubt that it is desirable to avoid the discharge of microplastics into wastewater.

The object of the present invention is therefore to provide a cleaning sponge that avoids the problems of the prior art and does not release any or at least hardly any microplastics during use, but nevertheless cleans efficiently and gently. The cleaning sponge should be as universally usable as possible for cleaning different surfaces, and particularly suitable for use when cleaning tableware and cookware such as pots or pans, including cookware with scratch-sensitive surfaces such as Teflon coatings or other non-stick coatings.

The object is solved by the cleaning sponge as claimed in independent claim 1 and by the methods of manufacturing the cleaning sponge as claimed in independent claims 11 and 12. Advantageous embodiments are claimed in the respective dependent claims.

The cleaning sponge and methods of making it are aspects of the same invention. Statements made in connection with one aspect of the invention therefore apply in the same way to the respective other aspect of the invention.

The cleaning sponge according to the invention consists of a carrier body that is equipped with a coating, the coating representing the component that fulfills the actual cleaning task.

The carrier body is of a conventional type. It is a foam body with two opposite main surfaces, it being possible for one or both main surfaces to be provided with a coating according to the invention. The dimensions are advantageously chosen so that the cleaning sponge has the largest possible cleaning surface, is thick enough not to tear, and fits well in the hand of the person cleaning.

In principle, all foam materials that are stable under cleaning conditions, i.e. withstand the mechanical forces that act on the sponge during a cleaning process, and that are also stable against the effects of water and common cleaning agents, can be used as materials for the carrier body of the cleaning sponge. A proven material is polyurethane. According to the invention, foam bodies made of polyurethane are preferably used for the carrier body.

Polyurethane is a plastic that decomposes under the influence of UV light (daylight) and moisture, and in the last stage it is also broken down by microorganisms. Cleaning sponges made of polyurethane foam can therefore lead to the formation of microplastics after disposal. However, this microplastic, which can occur at some point when a discarded cleaning sponge decomposes, does not usually end up in the wastewater. However, it may be desirable to minimize the amount of polyurethane used. According to a further preferred embodiment, a composite body made of at least two foam material layers which are connected to one another by means of an adhesive layer is therefore used as the carrier body within the scope of this invention. One of the layers is made of a natural material that does not degrade into microplastics, for example a cellulose-based material such as viscose. The surface of the carrier body provided with the coating is preferably a polyurethane surface, which is why a cleaning sponge is provided with a coating according to the invention on both sides is equipped, preferably has either a carrier body made of polyurethane foam or a sandwich-like composite carrier body with a central viscose foam layer and two outer layers of polyurethane foam. This is how the adhesion between the polyurethane binder of the coating and the coated surface is best.

Alternatively, a composite carrier body made of at least two foam materials, which are connected to one another by means of an adhesive layer, can also have a layer made of a material with special cleaning properties instead of a layer made of a natural material. Such a layer is, for example, a layer of melamine resin. Open-pored melamine resin sponges are known as "dirt erasers". Such foams can also be used with advantage in the present invention. Of course, in the case of a composite of a foam material such as polyurethane and a melamine resin foam material, the cleaning coating is not on the melamine resin layer but on the layer of the other foam material.

A polyurethane adhesive is preferably used to bond the layers of the composite carrier body to one another, particularly if at least one of the layers consists of polyurethane.

The surface of the carrier body to be coated can be flat, ie flat, or have a three-dimensional surface structure. Three-dimensional surface structures are, for example, groove-like elevations and depressions that are arranged alternately, or island-like elevations and depressions that form a grid. Such structures of the carrier body surface are transferred to the Coating and can improve the cleaning effect, since on the one hand the raised areas can contribute to breaking up the impurities and on the other hand the detached impurities can be absorbed by the depressions and transported away by the cleaning liquid. The cleaning surface is therefore not blocked by loosened dirt.

The coating consists of at least two types of components, the cleaning particles and a binder in which the particles are distributed and which connects them to a surface of the carrier body.

A polyurethane or a mixture of polyurethanes is used as the binder in the present invention. Like the carrier body, the polyurethane binder must be chemically and mechanically stable under cleaning conditions. When selecting a suitable polyurethane binder, it is also preferable to consider criteria such as its viscosity in the uncrosslinked state and its hardness and elongation at break in the crosslinked state.

The viscosity is important in particular with regard to good application properties and good anchoring of the coating on the surface of the carrier body. The binder should preferably be sufficiently viscous that no penetration into the interior of the carrier body takes place, but still be sufficiently fluid to allow penetration into surface pores of the carrier body, as a result of which improved fixing of the coating to the carrier body is achieved. The viscosity of the polyurethane binder is preferably in the range from 1,000 to 12,000 mPas, or the viscosity of the coating composition in the range from 5,000 to 12,000 mPas, particularly preferably in the range from 7,000 to 10,000 mPas.

In the present invention, the term "viscosity" means dynamic viscosity. It is determined using a Brookfield viscometer according to ISO 2555.

The hardness of the coating plays a role in both the cleaning properties and the durability of the connection between the carrier body and the coating. The hardness of the coating should be high enough to support the cleaning particles during cleaning, but it must not be too high either, since the cleaning sponge must remain flexible overall. The Shore A hardness of the cured coating is preferably in the range from 25 to 85. A Shore A hardness of from 40 to 70 is particularly preferred. The Shore A hardness is determined according to ASTM D2240-00 using a Shore durometer.

The elongation at break of the crosslinked coating is preferably in the range from 40 to 150%, particularly preferably in the range from 50 to 100%. An elongation at break in this range guarantees sufficient flexibility of the coating that the coating can follow the deformation of the soft carrier body during a cleaning process. Sufficient elongation at break in combination with a hardness that is not too great also ensures that the connection between the soft carrier body and the coating remains stable under mechanical stress and deformation during the cleaning process. Elongation at break is determined according to ASTM D-3574, Method E. This is basically a procedure for testing PU foam. However, the test principle can also be applied to flexible polymer films.

It has been found that 1-component polyurethane resins, such as those known as assembly foams, are well suited for the purposes of the present invention. Of course, no blowing agent is used in the present invention since foaming is not desired. Solvents are also preferably not included. The proportion of free isocyanate groups in the prepolymers is preferably from 3 to 10% by weight. The 1-component polyurethane resins harden within a few hours at 20 to 25° C through a reaction with atmospheric moisture. Particularly preferred binders are polyurethane prepolymers based on a diphenylmethane diisocyanate adduct with diols and triols. As a commercially available product, Everad RPM 2644 (from Everad Adhesives, France) can be mentioned, for example.

The polyurethane prepolymers can be prepared, for example, by reacting a diisocyanate such as 4,4-diphenylmethane diisocyanate with at least one diol and/or triol in the presence of a tin or amine catalyst. The diols and triols (i.e. polyols) used preferably have a molar mass between 1000 and 5000 g/mol and a hydroxyl number between 40 and 100 mg KOH/g. Polyether polyols are particularly preferred. The molar ratio between the isocyanate used and the polyol used is chosen depending on the viscosity of the desired finished prepolymer. Typically, the molar ratio of isocyanate:polyol ranges from 30:70 to 50:50.

1-component polyurethane resins are particularly preferred because they are very easy to process. However, the present invention is not limited to the use of 1-component polyurethane resins.

The core of the present invention lies in the use of specific cleaning particles. According to the invention, no plastic particles are used as cleaning particles, but rather natural particles. These have the advantage that no microplastics get into the waste water if particles become detached from the coating when using the cleaning sponge, especially if it is used for a long time. However, natural particles also have disadvantages compared to plastic particles. In particular, they tend to scratch delicate surfaces and are less well retained by the binder plastic than plastic particles. Therefore, when using the cleaning sponge, there is a greater risk of particles detaching from the coating, which is harmless from an environmental point of view, but reduces the service life of the cleaning sponge.

According to the invention, it has now been found that certain natural materials, if they are used in a suitable size, do not have these disadvantages, but are cleaned gently and fixed well and permanently in the coating by a polyurethane binder. Cleaning sponges that have a polyurethane coating with such particles distributed therein can therefore be used to clean sensitive surfaces, such as Teflon-coated pans and other cookware with a non-stick coating, and have a long service life.

The natural materials suitable for the purposes of the present invention can be divided into two groups. Particles of the first group are hereinafter referred to as "abrasive particles" and particles of the second group are hereinafter referred to as "non-abrasive particles". What both groups have in common is that they are very good and clean gently, but the cleaning properties of the particles in the first group are even better than the particles in the second group, while the particles in the second group clean even more gently than the particles in the first group.

Abrasive particles include particles of pumice, silica sand, glass, corundum, and calcined bauxite. These materials are brought to suitable particle sizes in the range of preferably 20 μm to 1000 μm by grinding. Particle sizes in the range from 50 μm to 500 μm are particularly suitable. Only a single type of particle can be used in a coating, for example only particles of pumice stone, or any mixture of several of the particles mentioned can be used.

Grinding creates edges that are particularly suitable for breaking up dirt. At the same time, the materials are not so hard that they are too abrasive and result in scratching of the treated surfaces. This applies in particular to smaller particles with a size in the range from 50 to 300 μm.

The most suitable material from the first group is pumice stone, in particular pumice stone with a particle size in the range of 50 to 500 µm. This material perfectly embodies the desired properties. It is hard enough and the edges of the particles produced during grinding are sharp enough to have an abrasive cleaning effect, but at the same time the hardness and edge sharpness are not so great that surfaces to be cleaned are easily scratched. An upper particle size limit of 500 µm is desirable insofar as larger particles tend to break during the cleaning process, which can result in sharp edges that clean less gently.

Pumice also has the advantage that it is particularly well fixed in the polyurethane binder. This is probably due to the porosity of the pumice particles.

Non-abrasive particles include precipitated silica, river sand, desert sand, and walnut shell powder. These particles can also be used alone, ie only one type of particle in a coating, or in any combination of two or more types of particles.

Suitable particle sizes are preferably in the range from 20 μm to 1000 μm, particle sizes in the range from 100 μm to 500 μm are particularly preferred, and the best and gentlest cleaning effect is achieved with particle sizes in the range from approx. 250 μm to 350 μm.

The following generally applies to abrasive and non-abrasive particles: the larger the particles, the better the cleaning effect, and the smaller the particles, the gentler the cleaning. The term “particle size” is to be understood in the present invention as meaning that with a particle size of x μm to y μm, all particles pass through a sieve with a mesh size of y μm, but do not pass through a sieve with a mesh size of x μm.

The non-abrasive particles mentioned above have in common that they have an approximately rounded shape, ie there are no sharp edges. River sand is carried by the current and is rounded in the process, while desert sand is carried by the wind and is also rounded in the process will. Grinding walnut shells produces a relatively soft powder with no sharp edges.

Strictly speaking, precipitated silica is not a "natural" material, since it is produced artificially by precipitation from water glass. However, since it is identical in chemical composition to natural materials, it is regarded as a natural material in the present invention. Precipitated silicon dioxide, also commonly referred to as "silica", is the most suitable material from the group of non-abrasive particles for the purposes of the present invention. The hydrated silica has no sharp edges. Rather, it is in the form of essentially round particles. It cleans particularly gently and is excellently fixed by the polyurethane binder, which is probably due to the porosity of the silicon dioxide particles. The most suitable material for cleaning highly sensitive surfaces is therefore precipitated silica with a particle size range of 100 µm to 500 µm. As an example of a commercially available material, Sipernat 2200 from Dow Chemicals can be mentioned.

Walnut shell powder is also ideal, but it is not as easy to process as the other materials mentioned. When mixed with the polyurethane binder, it tends to foam the polyurethane, which can lead to instability in the application process. It may be necessary to add defoamers to a coating composition containing walnut shell powder.

Coatings according to the invention can consist exclusively of polyurethane binder and cleaning particles distributed therein, but they can also contain other components if these affect the properties do not interfere with the coating. As a rule, the coatings are colored, ie they contain at least one coloring substance in addition to the polyurethane binder and the cleaning particles. Coloring substances are organic or inorganic pigments and inorganic or organic dyes. Unlike dyes, which are soluble, pigments are made up of particles. When using pigments, care must be taken not to use pigments that are too hard or particles that are too large, in order to prevent the pigments themselves from acting as "cleaning particles" and scratching the surfaces to be cleaned. Suitable coloring substances are commercially available. An example is Hostaperm Yellow H3G from Clariant GmbH.

The proportion of the coloring substance in the coating should preferably not exceed a quantity of about 4% by weight. A typical amount is about 0.5% by weight. The coating can contain other additives known per se in the field of plastic coatings, but preferably contains only polyurethane binders, cleaning particles, and optionally one or more coloring substances.

The production of a cleaning sponge according to the invention is preferably carried out in such a way that a polyurethane binder, cleaning particles and optionally a coloring substance and / or other auxiliaries are mixed in the respectively desired amounts to form a coating composition, then the coating composition is applied to a main surface of a carrier body made of a foam material is applied and then cured in air.

The coating compositions preferably contain, in the case of abrasive cleaning particles, 60 to 80% by weight polyurethane binder, balance abrasive particles and up to 4% by weight coloring substance, i.e. 16 to 40% by weight abrasive cleaning particles. The compositions particularly preferably contain 65 to 70% by weight of polyurethane binder, 27.5 to 34.7% by weight of abrasive particles and 0.3 to 2.5% by weight of inorganic and/or organic pigments. Pumice particles are preferably used as the abrasive particles, and a 1-component polyurethane resin is preferably used as the polyurethane binder.

In the case of non-abrasive cleaning particles, the coating compositions preferably contain 75 to 95% by weight polyurethane binder, the balance non-abrasive particles and up to 4% by weight coloring substance, i.e. 1 to 25% by weight non-abrasive particles. The coating compositions particularly preferably contain 82.5 to 89.5% by weight of polyurethane binder, 8 to 17.2% by weight of non-abrasive particles and 0.3 to 2.5% by weight of inorganic and/or organic pigments . Silica particles are preferably used as the non-abrasive particles, and a one-component polyurethane resin is preferably used as the binder.

It goes without saying that the percentages each add up to 100%.

The coating composition is preferably applied to a surface of the carrier body by roller application. Roller application processes are preferred insofar as they lead to particularly good anchoring of the cleaning particles in the polyurethane film and the coating result is very homogeneous and visually attractive. To achieve an optimal coating result, a polyurethane resin is preferred selected which gives a coating composition with a viscosity in the range from 5,000 to 12,000 mPas, preferably from 7,000 to 10,000 mPas. Such polyurethane resins have a viscosity in the range from 1500 to 7000 mPas.

The coating composition is then cured, ie the polyurethane resin is crosslinked. The curing conditions depend on the type of polyurethane resin used. A 1-component polyurethane resin which cures in air by reaction with atmospheric moisture at 20 to 25° C. within 2 to 8 hours is preferred. At low atmospheric humidity (less than about 40%), it may be necessary to moisten the substrate surface to be coated with water before applying the coating composition.

Alternatively, the polyurethane resin can also first be applied to a surface of the carrier body, for example by roller application or by spraying, and then the abrasive or non-abrasive particles are scattered onto the polyurethane resin film, which is still wet. In the case of roller application, preference is given to using a polyurethane resin with a viscosity in the range from 5,000 to 12,000 mPas, preferably from 7,000 to 10,000 mPas, and in the case of spraying on the polyurethane resin, preference is given to a polyurethane resin with a viscosity in the range from 1,000 to 5,000 mPas from 1,500 to 3,000 mPas.

After the cleaning particles have been sprinkled on, the polyurethane resin is crosslinked. The crosslinking conditions depend in turn on the type of polyurethane resin used, preference being given to a 1-component polyurethane resin which cures in air by reaction with atmospheric moisture at 20 to 25° C. within 2 to 8 hours.

The coating composition or the polyurethane resin can be applied to a "finished" carrier body or composite carrier body, i.e. to a carrier body with the dimensions of the cleaning sponge to be produced, but alternatively a carrier body panel or composite carrier body panel can also be coated, from which, after the coating has cured, the cleaning sponges can be produced in be cut or punched out to the desired dimensions and shapes. In addition, after one of the surfaces of a (composite) carrier body has been coated and the coating has cured, the opposite surface of the (composite) carrier body can also be provided with a coating according to the invention or another coating. It is also possible to first coat one of the layers (carrier) of a composite carrier body and then to bond this coated carrier body to one or more further layers (for example made of cellulose or melamine resin) on its uncoated surface.

Preferred coating thicknesses are in the range from 0.5 to 4 mm, particularly preferably in the range from 1 to 3 mm. Preferred coating weights are in the range from 200 to 500 g/m ² , more preferably in the range from 250 to 400 g/m ² .

The invention is further illustrated below with reference to figures. It is noted that the figures are not to scale and are not in proportion. Furthermore, features disclosed in connection with a particular figure should in no way be understood to mean that the features in question can only be used in combination with the others in the figure corresponding figure shown and / or described features are applicable.

• Fig. 1 eine Ausführungsform eines erfindungsgemäßen Reinigungsschwamms,
• Fig. 2 eine alternative Ausführungsform eines erfindungsgemäßen Reinigungsschwamms,
• Fig. 3 eine Aufsicht auf einen erfindungsgemäßen Reinigungsschwamm, und
• Fig. 4 einen Schnitt durch den in Fig. 3 dargestellten Reinigungsschwamm entlang der Linie A-A'.

In the figures, the same reference numbers denote the same or corresponding elements. Show it:

• 1 an embodiment of a cleaning sponge according to the invention,
• 2 an alternative embodiment of a cleaning sponge according to the invention,
• 3 a top view of a cleaning sponge according to the invention, and
• 4 a cut through the in 3 illustrated cleaning sponge along the line A-A'.

1 shows an embodiment of a cleaning sponge 1 according to the invention. The cleaning sponge 1 shown has a carrier body 2 made of polyurethane foam material with a first main surface 2' and a second main surface 2". The first main surface 2' is covered by a coating 3 made of polyurethane with it distributed abrasive or non-abrasive particles 4. The surface 3' of the coating 3 forms the cleaning surface of the cleaning sponge 1. The particles 4 are in the 1 embodiment shown is randomly distributed in the coating 3, as is the case when a coating composition of polyurethane resin having particles 4 dispersed therein is applied to the support body 2. On the other hand, the polyurethane resin is used first applied to the carrier body 2 and then the particles 4 scattered onto the not yet crosslinked polyurethane resin, the particles 4 are more localized on the surface 3 ′ of the coating 3 . With a localization of the particles 4 more on the surface of the coating 3, fewer particles 4 are needed than with a statistical distribution of the particles 4 throughout the volume of the coating 3. However, cleaning sponges with a statistical distribution of the particles 4 throughout the volume of the coating 3 have a longer service life, since the particles 4 are more permanently anchored in the coating 3.

2 shows an alternative embodiment of a cleaning sponge 1 according to the invention 2 In the illustrated embodiment, the carrier body is a composite body made of a foam layer 5 made of polyurethane and a foam layer 7 made of viscose, which are connected by means of an adhesive layer 6 . The surface of the polyurethane foam layer that is not bonded to the viscose foam layer is equipped with a coating 3 in which abrasive or non-abrasive particles 4 are randomly distributed. The surface 3' of the coating 3 represents the cleaning surface of the cleaning sponge 1.

In the 2 The illustrated embodiment of the cleaning sponge 1 essentially has the shape of a cuboid, while the 1 illustrated embodiment is more cubic. However, the shape of the cleaning sponges is basically arbitrary, with shapes being preferred that are simple (and therefore inexpensive) to produce. shapes like them in 1 and 2 may be die cut from foam sheet without waste, but the present invention is not limited to such shapes. Rather, the cleaning sponges according to the invention can also have any desired curved contours, for example contours which make it easier to reach places that are difficult to access. Alternatively or additionally, opposite side faces of a cleaning sponge can have indentations that make it possible to better and more securely hold the cleaning sponge during a cleaning process.

At the in 1 and 2 cleaning sponges 1 shown, only one surface of the carrier body 2 is equipped with a coating 3. Alternatively, however, the second main surface 2" could also be equipped with a coating according to the invention or another coating. It is also possible to provide a coating 3 according to the invention with abrasive particles on one main surface of the carrier body 2 and a coating 3 according to the invention on the other main surface of the carrier body 2 Coating 3 provided with non-abrasive particles.

In addition, a carrier body 2 can also be a composite body made up of more than 2 layers that are connected by means of an adhesive (as in 2 shown), be. For example, the in 2 shown composite body on the main surface 2 "of the foam layer 7 made of viscose can be connected by means of a further adhesive layer to a further foam layer made of polyurethane, which in turn could have a coating 3 according to the present invention.

The in the Figures 1 and 2 The cleaning sponges 1 shown each have unstructured surfaces or main surfaces. However, the coating 3 according to the invention can be applied not only to flat surfaces, but also to surfaces with a largely random structure. An example of a cleaning sponge 1 with a structured surface is in the Figures 3 and 4 shown.

3 shows a plan view of the cleaning surface 3 'of a cleaning sponge 1 according to the invention, and 4 shows the in 3 illustrated cleaning sponge in cross section along the line AA '. How out 3 As can be seen, the surface 3' has a three-dimensional structure with elevations 8 and depressions 9 arranged alternately in a regular grid 3 the maxima of the elevations 8 are shown as solid circles, while the minima of the depressions 9 are shown as dotted circles. The particles 4 are in 3 not shown. Viewed in cross section ( 4 ) such a raster forms a waveform.

The cleaning sponges according to the invention can also have any other three-dimensional surface structures, for example grooves, which can contribute to improving the cleaning effect.

The cleaning sponges according to the invention have a long service life. This also means that they pollute the environment less with waste plastic than less resistant and therefore short-lived cleaning sponges. At the end of their useful life, the cleaning sponges according to the invention can be decomposed under the influence of daylight (UV light) and moisture, and ultimately also by microorganisms. Alternatively, thermal recycling is also possible.

Claims (15)

Cleaning sponge (1) having a carrier body (2) made of a foam material, which has two opposite main surfaces (2', 2"), and a coating (3) on at least one of the main surfaces of the carrier body (2), characterized in that the coating (3) consists of a composition comprising polyurethane and abrasive or non-abrasive particles (4) distributed therein, wherein the abrasive particles (4) are selected from the group consisting of pumice particles, silica sand particles, glass particles, corundum particles, calcined bauxite particles and mixtures thereof and have a size in the range of 20 µm to 1000 µm, and the non-abrasive particles (4) are selected from the group consisting of precipitated silica, river sand, desert sand, walnut shell powder and mixtures thereof and have a size ranging from 20 µm to 1000 µm. Cleaning sponge (1) according to Claim 1, characterized in that the coating (3) contains pumice particles with a size of 20 to 500 µm. Cleaning sponge (1) according to Claim 1, characterized in that the coating (3) contains particles (4) of precipitated silicon dioxide with a size of 100 to 500 µm. Cleaning sponge (1) according to Claim 1 or 2, characterized in that the coating (3) consists of a composition which contains 60 to 80% by weight of polyurethane as a binder, the remainder being abrasive particles (4) and up to 4% by weight of a coloring substance, preferably 65 to 70% by weight polyurethane as a binder, 27.5 to 34.7% by weight pumice particles and 0.3 to 2.5% by weight inorganic and/or or contains organic pigments. Cleaning sponge (1) according to Claim 1 or 3, characterized in that the coating (3) consists of a composition which contains 75 to 95% by weight of polyurethane as a binder, the remainder being non-abrasive particles (4) and up to 4% by weight. % of a coloring substance, preferably 82.5 to 89.5% by weight of polyurethane as a binder, 8 to 17.2% by weight of precipitated silicon dioxide and 0.3 to 2.5% by weight of inorganic and/or organic pigments contains. Cleaning sponge (1) according to one of Claims 1 to 5, characterized in that the coating (3) has a Shore A hardness of 25 to 85, preferably 40 to 70. Cleaning sponge (1) according to one of Claims 1 to 6, characterized in that the coating (3) has an elongation at break of 40 to 150%, preferably 50 to 100%. Cleaning sponge (1) according to one of Claims 1 to 7, characterized in that the carrier body (2) is a sponge body made from polyurethane or a composite body made from a sponge body (7) based on cellulose or made from melamine resin and a sponge body (5) made from polyurethane , which are connected by means of a polyurethane adhesive (6), with the composite body having the coating (3) on the sponge body (5) made of polyurethane. Cleaning sponge (1) according to one of Claims 1 to 8, characterized in that at least one main surface (2') of the carrier body (2) has a three-dimensional surface finish with grid-like arrangements Has elevations (8) and depressions (9), the coating (3) being on the main surface (2') with a three-dimensional surface finish. Cleaning sponge (1) according to one of Claims 1 to 9, characterized in that the carrier body (2) has a coating (3) on one of its main surfaces (2') which contains abrasive particles (4) and on the opposite main surface ( 2") has a coating (3) containing non-abrasive particles (4). A method of manufacturing a cleaning sponge (1) as claimed in any one of claims 1 to 10, comprising the steps of: - providing a carrier body (2) made of a foam material, which has two opposite main surfaces (2', 2"), - preparing a coating composition by mixing abrasive or non-abrasive particles (4) into a polyurethane resin, wherein the abrasive particles (4) are selected from the group consisting of pumice particles, silica sand particles, glass particles, corundum particles, calcined bauxite particles and mixtures thereof , and having a size in the range of 20 µm to 1000 µm, and wherein the non-abrasive particles (4) are selected from the group consisting of precipitated silica, river sand, desert sand, walnut shell powder and mixtures thereof, and having a size in the range of have 20 µm to 1,000 µm, - applying the coating composition to one of the main surfaces (2', 2") of the carrier body (2), and - allowing the coating composition to cure. A method of manufacturing a cleaning sponge (1) as claimed in any one of claims 1 to 10, comprising the steps of: - providing a carrier body (2) made of a foam material, which has two opposite main surfaces (2', 2"), - Applying a polyurethane resin to one of the main surfaces (2', 2") of the carrier body (2) to produce a polyurethane resin coating, - Distributing abrasive or non-abrasive particles (4) on the polyurethane resin coating, the abrasive particles (4) being selected from the group consisting of pumice particles, silica sand particles, glass particles, corundum particles, calcined bauxite particles and mixtures thereof, and have a size in the range of 20 microns to 1000 microns, and the non-abrasive particles (4) are selected from the group consisting of precipitated silica, river sand, desert sand, walnut shell powder and mixtures thereof, and a size in the range of 20 microns to have 1,000 µm, and - Allow the polyurethane resin to harden. The method according to claim 11 or 12, characterized in that the coating composition, which is applied to the carrier body (2), has a viscosity in the range from 5,000 to 12,000 mPas, preferably from 7,000 to 10,000 mPas, or that the polyurethane resin on the Carrier body (2) is applied, has a viscosity in the range from 5,000 to 12,000 or in the range from 1,000 to 5,000 mPas. Method according to one of Claims 11 to 13, characterized in that the polyurethane resin is a 1-component polyurethane resin which cures in air by reaction with atmospheric moisture at 20 to 25°C within two to eight hours. Method according to one of Claims 11 to 14, characterized in that the carrier body (2) consists of a foam material, in particular a sponge body made of polyurethane, which after the coating composition or the polyurethane resin has been allowed to harden on its uncoated main surface (2', 2 ") is glued to a sponge body based on cellulose or melamine resin to form a composite carrier body.

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