MX2007000429A

MX2007000429A - A cleaning implement comprising a layer of melamine foam.

Info

Publication number: MX2007000429A
Application number: MX2007000429A
Authority: MX
Inventors: Alan Scott Goldstein; Gary Ashe
Original assignee: Procter & Gamble
Priority date: 2004-07-12
Filing date: 2005-07-11
Publication date: 2007-03-07
Also published as: WO2006017298A1; CA2573270A1; US20060005338A1; EP1776033A1; JP2008505734A

Abstract

The present invention relates to a cleaning implement (1) comprising a layerof melamine foam (2), having a thickness of at least 15 mm, and a layer of a secondfoam (3) having a water-absorbency of at least 0.35 g of water per cm3 of said secondfoam.

Description

CLEANING IMPLEMENT COMPRISING A MELAMINE FOAM LAYER TECHNICAL FIELD The present invention relates to a cleaning implement comprising a layer of melamine foam and a layer of a second foam.

BACKGROUND OF THE INVENTION Melamine formaldehyde resin foams, also referred to herein as melamine foams are well known in the industry for use in industrial applications, for example as heat or sound insulating materials and also as fire protection. Clearly, in the automotive industry, melamine foam is commonly used to insulate engine compartments and cabins from automobile and truck drivers. A novel application for these melamine foams in the area of hard surface cleaning has recently been discovered. Clearly, the cleaning implements of cut or molded melamine foam pieces have become popular for removing dirt and / or stains from hard surfaces (ie for cleaning hard surfaces) such as tiles, walls, floors, faucets and sanitary fittings such as sinks, showers, shower curtains, sinks, toilets, appliances that include, but are not limited to, refrigerators, freezers, washing machines, automatic dryers, ovens, microwave ovens, dishwashers, etc. Clearly, melamine foam sponges are currently distributed on the market under the trademark Mr. Clean Magic Eraser®. To stabilize the melamine foam and to prevent it from disintegrating in advance, sponges combining a melamine foam and a stabilizing material, such as a rigid polyurethane (marketed under the trademark Scotch Brite Easy Erasing Pad® by 3M) have been offered and marketed. Corp.). Pieces of melamine foam combined with a second material or laminated in a second material are known in the industry, for example, in U.S. Pat. no. 2001/0024720 or in Japanese patent 2001-258809. It has been observed that melamine foam shows excellent performance in the removal of dirt and / or stains when used to clean hard surfaces. Clearly, it has been observed that if the melamine foam is moistened with an appropriate solvent such as tap water, it removes dirt and / or stains from a hard surface when that hard surface is brought into contact with that moistened melamine foam. "Contact" means to clean, wipe, rub or the like. For optimum melamine foam to remove dirt and / or stains from hard surfaces, substantial amounts of an appropriate solvent, such as tap water, must be used. Most commonly, melamine foam users use tap water when they remove dirt and / or stains from hard surfaces. If used with water or any other suitable solvent, the melamine foam separates out as small particles (ie the foam disintegrates) when it comes into contact with a hard surface. Clearly, a milky suspension of melamine foam particles in water is formed. Through consumer surveys it has been discovered that when users of melamine foams remove dirt and / or stains from hard surfaces they try to find a way to absorb the excessive amounts of water that have been used and also the milky suspension of small particles. of melamine foam in water. Although the melamine foam alone can absorb water and / or a milky suspension of melamine-water, users consider that melamine foam does not absorb enough water and / or milky melamine suspension. Water. The same applies to currently commercially available sponges in which the melamine foam is combined with a stabilizing material, since the stabilizing material used alone or combined with the melamine foam does not have the capacity to absorb sufficient quantities of water and / or Milky suspension of melamine-water. Likewise, for a user of melamine foams who use them to remove dirt and / or stains from hard surfaces, it is not convenient to use a separate absorbent utensil, such as an absorbent paper towel, a sponge or a cloth, in addition to the melamine foam for absorb the excessive amounts of water that have been used and also the milky suspension of melamine-water. Therefore, an object of the present invention is to provide a cleaning implement based on melamine foam, wherein that implement has the capacity to absorb excessive amounts of water (or other appropriate solvent) that have been used and also the milky suspension of melamine-water (ie, the milky suspension of small particles of melamine foam in water (solvent)) generated during use. It has now been found that the above objective can be met by means of a cleaning implement comprising a layer of melamine foam with a thickness of at least 15 mm, and a layer of a second foam having a water absorbency of at least 0. 35 g of water per cm3 of that second foam. Conveniently, the thickness of at least 15 mm of the melamine foam layer in the cleaning implement of the present invention causes the amount of melamine foam provided to be sufficient for an acceptable amount of cleaning operations (i.e., removal). of dirt and / or stains of hard surfaces). Another advantage of the cleaning implement of the present is that the second foam not only absorbs the excessive amounts of water that have been used and the milky suspension of melamine-water, but also provides stability to the cleaning implement. Clearly, it has been found that unstabilized melamine foam tends to be broken or punctured when used to remove dirt and / or stains from hard surfaces due to its relative brittleness and also to the irregular pressure that the user exerts when put in contact with it. with the hard surfaces to be cleaned.

BRIEF DESCRIPTION OF THE INVENTION The present invention encompasses a cleaning implement comprising a layer of melamine foam having a thickness of at least 15 mm and a layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam. The present invention also encompasses a cleaning implement comprising a layer of melamine foam having a thickness of at least 15 mm and a layer of a second foam, wherein the layers are joined to each other by means of foam lamination by flame. The present invention also encompasses a method of cleaning a hard surface by means of contact between a cleaning implement according to the present invention and that hard surface, preferably where that cleaning implement has been moistened with an appropriate solvent (water of the tap) before putting that cleaning implement in contact with that hard surface.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a cleaning implement in accordance with the present invention. Figure 2 is a top view of that implement. Figure 3 is a view of the base of that implement. Figure 4 is a side elevation view of that implement (the opposite side view is the same). Figure 5 is an end view of that implement (the opposite side view is the same). Figure 6 is a perspective view of a cleaning implement in accordance with the present invention showing the Mr. Clean® Head logo. Description of the reference numbers: 1: Cleaning implement 2: Melamine foam layer 3: Layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam 4: Line indicating the separation between the melamine foam layer and that second foam 5: Mr. Clean® Head Logo DETAILED DESCRIPTION OF THE INVENTION Cleaning implement The cleaning implement (1) herein comprises at least two separate layers. A first layer of melamine foam (2) having a thickness of at least 15 mm and a second layer of a second foam (3) having a water absorbency of at least 0.35 g of water per cm3 of that second foam. Here, the term "cleaning implement" refers to an industrialized article of any shape and / or size and / or volume suitable for cleaning, ie removing dirt and / or stains from hard surfaces. In a particularly preferred embodiment in accordance with the present invention, the shape and / or size and / or volume of the cleaning implement herein is suitable for a consumer to clean hard surfaces with that implement. The layers of melamine foam and second foam may be disposed on that cleaning implement in any suitable manner. In a preferred embodiment, the melamine foam and second foam layers are disposed parallel to at least one side, preferably to two opposite sides, of the cleaning implement. However, the cleaning implement can also have an irregular shape. Clearly, in the cleaning implement the thickness of the layers may be uniform or may vary. The separation line (4) between the two layers can form a straight line or a curve or can be completely irregular. In addition, the plane of separation of the layers can be in the center of the cleaning implement and thus divides the implement into two equal parts or can be on the top or bottom of the implement. In addition, the cleaning implement can have the shape of a sphere, a globule or an ellipsoid wherein the plane of separation of the layers forms a spherical segment or one of the layers, preferably the layer of a second foam of the present form a sphere in a sphere (similar to the layers of an onion). Suitable shapes for the cleaning implements of the present can be selected from the following group of shapes: cubic, rectangular, pyramidal, cylindrical, conical, pencil eraser, cuboid, tetrahedral, spherical, globular and ellipsoidal. Preferably, the shape of that cleaning implement is selected from the following group: cubic, rectangular, pencil eraser and cuboid. Suitable volumes of the cleaning implements herein can be from 1 cm3 to 10,000 cm3, preferably from 10 cm3 to 1000 cm3 and more preferably from 150 cm3 to 250 cm3. In a particularly preferred embodiment herein, the cleaning implement (1) of the present has a cuboid shape defined by three groups of parallel sides and of the same length, mentioned as a, b and c, where a ranges from 2 cm to 20 cm, preferably 4 cm to 8 cm, b ranges from 2 cm to 20 cm, preferably from 8 cm to 15 cm and c ranges from 1.5 cm to 5 cm, preferably from 2 cm to 4 cm. In this especially preferred embodiment, wherein the cleaning implement (1) of the present has a cuboid shape, the line indicating the separation (4) between the two layers (or the surface areas in which the two layers are joined) one to the other) of the implement is preferably substantially parallel (preferably parallel) to the side of the cuboid implement having the largest surface area (as illustrated in Figures 1-5). In another especially preferred embodiment herein, the cleaning implement of the present is in the form of a pencil eraser. In the present, "shape of a pencil eraser" refers to a bulky body that has six walls, where the three pairs of walls are parallel and of the same shape and size and where a pair of walls have a parallelogram shape and the other two pairs of walls are rectangular in shape. In this preferred embodiment, wherein the implement of the present is in the form of a pencil eraser, the line indicating the separation between the two layers (or the surface areas in which the two layers are attached to each other) of the implement is preferably substantially parallel (preferably parallel) to the side of the pencil eraser-shaped implement having the largest surface area. In order to obtain suitable cleaning implements in accordance with the present invention, the melamine foam layer and the second layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam have to be joined together. at each other. This joining can be done by any suitable means to join the two layers. The joint can be permanent (where the two layers can not be separated without substantial damage) or temporary (where the two layers can be separated without substantial damage). Suitable joining means providing a permanent bond are selected from the group formed by: bonding the two layers together by flame foam lamination; use of a permanent adhesive; seam between the two layers and punching to join the two layers, and combinations of these. Suitable attachment means that provide a temporary bond are selected from the group consisting of: a weak adhesive; Sailboat; and a water-soluble and water-based adhesive or coating; and combinations of these. In a preferred embodiment herein, the bonding of the layers is a permanent bond. Even more preferably, the layers are bonded together by flame foam lamination. Flame foam lamination is a continuous process that can adhere foams and additional materials, when present, to one or both sides of a foam in a single pass. The flame lamination process consists of passing a first foam (either the melamine foam of the present or the second foam of the present) on an open flame to produce a thin layer of foam / molten polymer. A second foam (the second foam of the present or the melamine foam of the present, depending on the first step) is pressed against the first foam while still in the molten state. The foams and additional material, when present, may adhere to one or both sides of the foam in a single pass. In addition, additional passes can be made. The strength of the bond depends on the foams and the additional material, when present, which are selected and also on the processing conditions (ie the type of gas, the height and propagation of the flame, the burning of the foam and the pressure of the point of grip). Clearly, it has been found that the cleaning implement according to the present invention wherein the melamine foam layer and the layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam they are joined to one another by means of flame foam lamination compared to the use of an adhesive does not demonstrate a strong bond line of the adhesive on the connecting surface between the two layers. In addition, no other chemicals (such as adhesives) are added to the cleaning implement that can be redeposited on the hard surface to be cleaned when the melamine foam layer has worn away. In view of this, the present invention also covers as a separate embodiment, a cleaning implement (1) comprising a layer of melamine foam (2) having a thickness of at least 15 mm and a layer of a second foam (2). ) wherein the layers are joined to each other by flame foam lamination. The cleaning implement according to the present invention comprises at least two separate layers as described herein. The cleaning implement may contain more than two layers, wherein those additional layers may be of the same material or similar materials as melamine foam or that second foam or may be made of another material having similar or different properties to those of that second foam. Clearly, the cleaning implement of the present may be configured as a sandwich having three layers. In a preferred embodiment, wherein the cleaning implement of the present is configured as a sandwich, the middle layer can be that second foam and at least one of the two outer layers is a melamine foam of which the second outer layer It is a melamine foam or other material that provides another characteristic, such as abrasiveness or greater rigidity. In the cleaning implement according to the present invention the layers can cover each other partially or totally. "Partial coverage" means that at least one of the layers overlaps the other layer (or other layers, if present) and is not completely covered by that other layer (or other layers, if present). "Total coverage" means that the layers of the cleaning implement are not completely covered with each other and that none of the layers substantially overlaps the other layer (or other layers)., if they are present). The ratio of that melamine foam to that second foam in the cleaning implement according to the present invention is preferably from 20: 1 to 1: 20 by volume, more preferably from 10: 1 to 1: 10 by volume, even more preferably from 5: 1 to 1: 1, with a higher preference still from 5: 1 to 2: 1 and most preferably from 4: 1 to 3: 1 in volume.

To obtain suitable cleaning implements in accordance with the present invention it may be necessary to modify the shape and / or the size of the raw materials of melamine foam and second foam. This modification can be done by any means known to those with industry experience. Suitable means for modifying the shape and / or size of the melamine foam and second foam raw materials can be selected from the group consisting of: compression, heat compression, shearing, tearing, tearing, and combinations thereof. The cleaning implement can be modified or processed later. In particular, that modification and / or subsequent processing of the cleaning implement can be used to associate a brand and / or logo of a hard surface cleaner with that cleaning implement. The modification and / or the subsequent appropriate processing of the cleaning implement may consist of printing on one or several sides of that cleaning implement and / or engraving one or several sides of that cleaning implement using heat and / or pressure, and combinations of these. A modified cleaning implement to associate a logo of a hard surface cleaner (Mr. Clean® Head logo) with that cleaning implement is illustrated in Figure 6, where that logo of a hard surface cleaner (Mr. logo) Clean® Head (5)) has been engraved or printed on that second foam.

Melamine Foam The cleaning implement (1) of the present invention comprises a layer of melamine foam (2) having a thickness of at least 15 mm. Here, "melamine foam" refers to a melamine formaldehyde resin foam. Here, "thickness" refers to the length in mm of the side whose extension is smaller compared to other sides of the melamine foam layer (the height of the melamine foam layer). In case the cleaning implement is rectangular in shape and the melamine foam layer extends parallel to the sides of the shape having the largest surface area (extensions in the x and y axes), the thickness can be mentioned as the extension in the direction of the y axis. In case the cleaning implement is irregular and / or the thickness of the melamine foam layer varies (ie the layer is thicker in some parts of the implement compared to others) it is sufficient that the The thickness of the melamine foam layer extends at least once over the thickness required herein. The thickness of the melamine foam layer herein is at least 15 mm, preferably from 15 mm to 100 mm, more preferably from 17 mm to 50 mm, still more preferably from 20 mm to 40 mm and with the maximum preference of 21 mm to 25 mm. The total volume of that layer of melamine foam in the cleaning implement of the present invention is preferably from 50 cm3 to 400 cm3, more preferably from 80 cm3 to 300 cm3, even more preferably from 150 cm3 to 275 cm3 and with the maximum preference of 200 cm3 to 250 cm3. A suitable melamine formaldehyde resin foam raw material is commercially available under the tradename Basotect® by BASF. The "melamine foam" described above can be prepared by mixing primary melamine and formaldehyde starting materials or a precursor thereof with a blowing agent, a catalyst and an emulsifier, injecting the resulting mixture into a mold and causing the reaction mixture generate heat through a suitable medium such as heating or irradiation with electromagnetic wave so that the formation of foam and curing occurs. The molar ratio of melamine to formaldehyde (ie, melamine: formaldehyde) to produce the precursor is preferably from 1: 1.5 to 1: 4, more preferably from 1: 2 to 1: 3.5 in melamine: formaldehyde. In addition, the number average molecular weight of the precursor is preferably 200 to 1000, more preferably 200 to 400. In additionFormaldehyde usually uses formalin, which is an aqueous solution of formaldehyde. As monomers for producing the precursor, the following various monomers may be used in an amount of 50 parts by weight (hereinafter abbreviated as "parts") or less, in particular 20 parts by weight or less per 100 parts by weight of the sum of melamine and formaldehyde, plus melamine and formaldehyde. As other melamine monomers, C1-5-substituted melamines such as methylolmelamine, methylmethylolmelamine and methylbutylolmelamine, urea, urethane, carbonic acid amides, dicyandiamide, guanidine, sulfuryl amides, sulfonic acid amides, aliphatic amines, phenols and the like can be used. derived from them. As aldehydes, acetaldehyde, trimethylol acetaldehyde, acrolein, benzaldehyde, furfurol, glyoxal, phthalaldehyde, terephthalaldehyde, etc. may be used. As the blowing agent, pentane, trichlorofluoromethane, trichlorotrifluoroethane, etc. can be used. However, the use of the so-called Fleons® as trichlorofluoromethane is regulated from the point of view of environmental problems and therefore not preferred. On the other hand, pentane is preferred since even when it is used in small quantities it generates foam easily, but when handling it, care should be taken as it is flammable and volatile. In addition, formic acid is commonly used as a catalyst and anionic surfactants, for example sodium sulfonate as an emulsifier. The amount of electromagnetic wave that will be irradiated to accelerate the curing reaction of the reaction mixtures is preferably adjusted to be from 500 to 1000 kW, in particular from 600 to 800 kW, in electric power consumption based on 1 kg of a aqueous solution of formaldehyde charged in the mold. In case this power consumption is not sufficient, the foam formed will be insufficient and the cured product obtaiwill have a high density. On the other hand, when the consumption of electric power is excessive, the pressure on the formation of foam becomes quite high and this produces the exhaustion of the mold and even the possibility of explosion. Accordingly, the electrical power consumption preferably falls within this range.

Second foam The cleaning implement (1) of the present invention also comprises a layer of a second foam (3) having a water absorbency of at least 0.35 g of water per cm3 of that second foam. Preferably, the water absorbency of that second foam is at least 0.4 g, more preferably at least 0.45 g, still more preferably at least 0.5 g, and most preferably at least 0.55 g and at least 0.575 g. g of water per cm3 of that second foam. Preferably, the total water absorbency of the layer of a second foam is preferably at least 10 g of water, preferably of at least 11 g of water, more preferably of at least 13 g of water and with the maximum preference of at least 15 g of water. That second foam can be made of any suitable foam material to provide the absorbency of water needed herein. The second foams suitable for use herein are selected from the group of foams having the necessary water absorbency and consisting of: polyurethane foams, polypropylene foams, polyethylene foams, cellulose foam sponges, sponges of natural origin , open cell polyester foams, cross-linked polyethylene foams; and combinations of these. In a preferred embodiment herein, the second foam is a polyurethane foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam. Polyurethane foams are generally prepared by the reaction of an active compound containing hydrogen (ie, a polyol) and a polyisocyanate, in the presence of a blowing agent such as water, and generally a reaction catalyst and a stabilizer. foam. In a particularly preferred embodiment herein, the second foam is a hydrophilic polyurethane ester foam. A suitable hydrophilic polyurethane ester foam is commercially available under the trade name Cellulex® by Foamez L.P. Hydrophilic polyurethane ester foams and their preparation are described in U.S. Pat. no. 6,756,416. This hydrophilic polyurethane ester foam does not expand significantly when absorbing and holding liquids. "Hydrophilic polyurethane ester foam" refers to a polyurethane ester foam capable of absorbing sufficient quantities of liquids, such as water. The preparation of the hydrophilic polyurethane ester foam described in U.S. Pat. no. No. 6,756,416 is made in the following manner: a) a polyurethane foam is formed by mixing the following components: 100 parts by weight of a polyol ester; from 20.0 to 62.0 parts by weight, based on 100 parts of polyol, of an isocyanate, wherein the isocyanate number is 1 0 or less; and from 1.0 to 3.0 parts by weight, based on 100 parts of polyol, of a stabilizing surfactant; and b) the polyurethane foam is treated in a caustic bath to form the hydrophilic polyurethane ester foam. The hydrophilic polyurethane ester foams described in U.S. Pat. no. 6,756,416 have a water absorption rate of at least 0.32 g of water per cm3 of foam (20 pounds of water per square foot). To calculate the water absorbency per cm3 of a foam material the dimensions (length x width x height) of a sample of the foam material in "cm" can be measured to determine the volume (cm3) of material used for the test. The initial weight of the sample is calculated and recorded in grams. The sample is immersed in water and then drained manually until it does not drip. The sample is reweighed and the weight recorded (grams). This weight is considered as the tare. The sample is then allowed to soak in a water tube for 1 minute. After 1 minute, it is removed from the tube and hung vertically so that the surplus water drips for 5 minutes. The sample is then weighed and that weight is recorded in grams (weight of the wet sample). The sample is drained manually and weighed until the tare is obtained. The steps of soaking, drip, weigh and drain are repeated three times for each sample. For each foam material, the above measurements are repeated with at least 12 samples. For each sample, the total amount of water absorbed is calculated by subtracting the tare weight from the wet sample. To calculate the absorbance of water per cm3 of a sample, the total amount of water absorbed in grams is divided by the total volume of the sample. To calculate the water absorbency per cm3 of a foam material, the calculated absorbency of water per cm3 of each of its samples is averaged. To calculate the total water absorbency of a foam layer, the dimensions (length x width x height) of the foam layer in "cm" can be measured to determine the volume (cm3) of material used for the test. The initial weight of the foam layer is calculated and recorded in grams. The foam layer is immersed in water and then drained manually until it does not drip. The foam layer is reweighed and the weight recorded (grams). This weight is considered as the tare. The foam layer is then allowed to soak in a water tube for 1 minute. After 1 minute, it is removed from the tube and hung vertically so that the surplus water drips for 5 minutes. The foam layer is weighed and the weight recorded in grams (weight of the wet foam layer). The foam layer is manually drained and weighed until the tare is obtained. The steps of soaking, dripping, weighing and draining are repeated three times for each layer of foam. For each foam layer, the above measurements are repeated with at least 12 samples. To calculate the total amount of water absorbed by each layer, subtract the weight from the wet sample and the results are averaged for the described repetitions. The above measurements are made at room temperature and normal humidity conditions and measurements are made with tap water. Preferably, the thickness of that layer of a second foam is up to 30 mm, preferably from 0.5 mm to 20 mm, more preferably from 1 mm to 15 mm, still more preferably from 2 mm to 10 mm and with the greatest Preference from 4 mm to 8 mm. The total volume of that layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam in the cleaning implement herein is preferably 10 cm3 to 100 cm3, more preferably from 20 cm3 to 70 cm3, even with more preference of 30 cm3 to 60 cm3 and most preferably from 40 cm3 to 50 cm3. In a preferred embodiment, that layer of a second foam having a water absorbency of at least 0.35 g of water per cm3 of that second foam is made of a material other than a melamine foam.

Additional material The cleaning implement may contain more than two layers, wherein these additional layers, if present, may be made of a material (additional material) other than that layer of melamine and that second foam. The additional material may be suitable to provide the cleaning implement with advantageous features, such as abrasiveness, greater rigidity or greater subjection. In view of this, that additional material can be a scrubbing material or pad, a rigid foam material, a handle made of thermoplastic material, wood, metal or combinations thereof, and the like.

Packaging means The cleaning implement of the present invention can be combined in an industrialized article with a packaging means. Herein, the packaging means can be any known means for packaging cleaning implements. Clearly, the packaging means especially suitable herein are selected from the group consisting of: paper bags, plastic bags, cartons, cardboard boxes, wrappers, plastic wrappers and paper wrappers, and the like and combinations thereof. Herein, the packaging means may be printed and / or modified. In particular, that printing and / or other modification can be used to associate a brand and / or logo of a hard surface cleaner with that cleaning implement.

Method for Cleaning a Hard Surface In another embodiment, the present invention encompasses a method of cleaning a hard surface by placing a cleaning implement in accordance with the present invention in contact with that hard surface. In the present, "clean" refers to removing dirt and / or stains from hard surfaces. The hard surfaces suitable here are tiles, walls, floors, faucets and sanitary fittings such as sinks, showers, shower curtains, sinks, toilets, appliances that include, but are not limited to, refrigerators, freezers, washing machines, automatic dryers, ovens, microwave ovens, dishwashers, etc. The method for cleaning a hard surface in accordance with the present invention may also include the step of wetting the cleaning implement with an appropriate solvent, preferably tap water, before putting the cleaning implement in contact with that hard surface.

Claims

NOVELTY OF THE INVENTION CLAIMS 1. A cleaning implement (1) comprising a layer of melamine foam (2) having a thickness of at least 15 mm and a layer of a second foam (3) having a water absorbency of at least 0.35 g of water per cm3 of the second foam. The cleaning implement (1) according to claim 1, further characterized in that it has a shape selected from the following group of shapes: cubic, rectangular, pyramidal, cylindrical, conical, pencil eraser, cuboid and tetrahedral. 3. The cleaning implement (1) according to any of the preceding claims, further characterized by having a volume of 1 cm3 to 10,000 cm3. The cleaning implement (1) according to any of the preceding claims, further characterized in that the layer of melamine foam (2) and the layer of a second foam (3) are joined by means of a permanent or temporary joint . 5. The cleaning implement (1) according to any of the preceding claims, further characterized in that the layer of melamine foam (2) and the layer of a second foam (3) are joined by a means that provides a permanent bond selected from the group formed by: joining the two layers together by means of flame foam lamination; use of a permanent adhesive; seam between the two layers and punching to join the two layers, and combinations of these. 6. The cleaning implement (1) according to any of the preceding claims, further characterized in that the layers are joined to each other by flame foam lamination. The cleaning implement (1) according to any of the preceding claims, further characterized in that the ratio of the melamine foam (2) to the second foam is from 20: 1 to 1: 20 by volume. The cleaning implement (1) according to any of the preceding claims, further characterized in that the thickness of the melamine foam layer (2) is from 15 mm to 100 mm. 9. The cleaning implement (1) according to any of the preceding claims, further characterized in that the melamine foam (2) is a melamine formaldehyde resin foam. The cleaning implement (1) according to any of the preceding claims, further characterized in that said second foam (3) has a water absorbency of at least 0.4 g of water per cm3 of the second foam. 11. The cleaning implement (1) according to any of the preceding claims, further characterized in that the second foam (3) is selected from the group of foams having a water absorbency of at least 0.35 g of water per cm3 of the second foam and which is formed by: polyurethane foams; polypropylene foams; polyethylene foams; cellulose foam sponges; sponges of natural origin; open cell polyester foams; and cross-linked polyethylene foams; and combinations of these. The cleaning implement (1) according to any of the preceding claims, further characterized in that the second foam (3) is a polyurethane foam having a water absorbency of at least 0.35 g of water per cm3 of the second foam. 13. The cleaning implement (1) according to any of the preceding claims, further characterized in that the second foam is a hydrophilic polyurethane ester foam. 14. The cleaning implement (1) according to any of the preceding claims, further characterized in that the layer of a second foam (3) has a total water absorbency of at least 10 g of water. 15. A cleaning implement (1) comprising a layer of melamine foam (2) having a thickness of at least 15 mm and a layer of a second foam (3), wherein the layers are joined to each other by flame foam lamination. 16. A method for cleaning a hard surface by placing a cleaning implement according to any of the preceding claims in contact with the hard surface. 17. The method for cleaning a hard surface according to claim 16, further characterized in that the method also includes the step of moistening the cleaning implement (1) with an appropriate solvent, before placing the cleaning implement in contact with the hard surface. . 18. The method for cleaning a hard surface according to claim 17, further characterized in that the appropriate solvent is water.