MXPA99010111A - Acidic limescale removal compositions - Google Patents

Abstract

The present invention relates to a liquid acidic composition suitable for removing limescale-containing stains from a hard-surface having a pH below 5, and comprising from 0.01%to 20%of the total composition of a sulfamic acid, from 0.01%to 45%by weight of the total composition of a second acid, and from 0.001%to 10%by weight of an acid-stable polymer selected from the group consisting of a polycarboxylate polymer, a sulphonated homopolymer of (poly) styrene, or a sulphonated copolymer of styrene with an ethylenically unsaturated comonomer, a vinylpyrrolidone homopolymer or copolymer, a polyalkoxylene glycol, and mixture thereof. These compositions provide improved shine to the surface treated as well as improved skin mildness to the user's skin while exhibiting effective limescale removal performance.

Description

ACID COMPOSITIONS FOR THE REMOVAL OF LIMESTONE INCRUSTATIONS TECHNICAL FIELD The present invention relates to acid compositions of hard surfaces, especially compositions for removing limescale.

BACKGROUND OF THE INVENTION The water in the tap contains a certain amount of solubilized ions that, with the evaporation of water, are eventually deposited as salts, such as calcium carbonate, on surfaces that are frequently in contact with water, resulting in an anesthetic appearance of the surfaces. The formation of limestones and the phenomenon of deposition are even more acute in places where the water is particularly hard. It is well known in the art that deposits of limescale can be chemically removed with acid solutions, and a wide variety of acidic cleaning compositions have been described for that purpose.

However, said compositions for removing limescale are perceived by consumers as irritating detergent compositions and several consumers suffer from skin irritation when using said compositions. When such liquid acid compositions are used, the user's hands are particularly prone to irritation. The above occurs when said compositions are used in a pure form and also when they are used in diluted form. Without being limited by theory, it is believed that acids can attack the upper layer of the epidermis of the skin and alter the natural pH of the skin. The above may result in the reduction of skin elasticity. The skin can also become more sensitive, resulting in dryness and roughness of the skin. In addition, the skin may become inflamed, turn red, feel burning and / or itching. Therefore, it is an object of the present invention to improve the smoothness of the skin of liquid acid compositions, especially acidic compositions for removing limescale. More particularly, it is an object of the present invention to provide acid compositions for removing limestones that are softer to the skin by exhibiting excellent limestone scale removal performance. Furthermore, it is also desirable that said liquid acid compositions have, in addition to the ability to effectively remove limescale deposits, the ability to provide a good shine to the surfaces to which they have been descaled. However, the brightness of the surface is often compromised by the low affinity that the hard surface has with water when it comes into contact with it. In fact, water has the tendency to form droplets on the surface rather than to form a thin film spread evenly over the surface. This results, as the water evaporates, in the precipitation of inorganic salts that are poorly soluble in water, such as magnesium / calcium carbonate and / or phosphate salts with the subsequent formation of watermarks on the surface and, in the long run , deposits of limestone incrustations, resulting in the anesthetic aspect of the surface. It is therefore another object of the present invention to improve the gloss provided on a surface treated with acidic compositions, especially acidic compositions for removing limescale. More particularly, it is another object of the present invention to provide liquid acid compositions that provide improved gloss to the treated surface showing excellent limestone scale removal performance. The present invention solves said problems by formulating the liquid acid compositions comprising the acid system, sulfamic acid and a second acid, and an acid stable polymer as described hereinafter. In fact, the gloss on the surface treated with the compositions of the present invention and the softness of the skin of said compositions are improved by providing excellent limestone scale removal performance to the surface treated therewith. In fact, less irritation of the skin is perceived by the user when the skin is contacted with the compositions of the present invention and less formation of water marks and / or limestone scale deposits are observed on a surface that has been treated with the compositions of the present invention and subsequently contacted with water, for example, during a rinsing operation. Another advantage of the present invention is that the gloss benefit provided to the hard surface treated with the compositions of the present invention persists even after several rinse cycles, thus providing long-lasting protection against the formation of watermarks and / or even deposits of limestones on the surface, and therefore surfaces with long-lasting gloss. In other words, the housewife will have the advantage of delaying the next limescale removal operation. Advantageously, the gloss benefits of the present are obtained at very low levels of acid stable polymers in the acid compositions of the present invention. Another advantage of the liquid acid compositions of the present invention comprising the acidic system and the acid stable polymer as described herein is that the treated surfaces become softer (the above can be perceived by touching said surfaces). This can also contribute to give the consumer the perception of a surface to which the incrustations were perfectly removed.

The compositions according to the present invention can be used on a variety of surfaces, including metal surfaces such as aluminum, chrome steel, stainless steel, synthetic materials such as vinyl, linoleum, glazed or unglazed ceramic lozetas, and / or enameled surfaces.

TECHNICAL BACKGROUND Limestone scale compositions comprising sulfamic acid are known in the art. EP-A-666 305 discloses acidic compositions for removing limescale comprising maleic acid and a second acid similar to sulfamic acid. However, acid stable polymers have not been described herein. JP-63-309596 discloses compositions for hard surfaces such as food utensils containing at least 10% surfactants and 0.3% one or more polystyrene sulfonic acids or salts thereof. The addition of polystyrenesulfonic acid or its salts in a liquid hard surface composition containing a surfactant allows water spots to be avoided. The acid system according to the present invention is not described. EP-A-467 472 discloses a hard surface liquid composition with cationic anti-static / anti-dirt cationic polymers. The cationic quatemized polymethacrylate includes beta (trialkylammonium) ethyl acrylates / acriiates. Also, although cationic and anionic polymers are preferred, nonionic polymers can be used as polymers of vinylpyrrolidone, methyl vinyl ether copolymer and maleic anhydride. The acid system according to the present invention is not described. WO 94/26858 discloses acidic compositions (pH 2-8) comprising a nonionic surfactant and an anionic polymer having an average molecular weight of less than 1,000,000, said polymer being free of quaternary nitrogen groups. The acid system of the present invention is not described.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a liquid acid composition suitable for removing stains containing limestones from a hard surface, having a pH of less than 5, and comprising 0.01% to % of the total composition of a sulfamic acid, from 0.01% to 45% by weight of the total composition of a second acid, and from 0.001% to 10% by weight of an acid stable polymer selected from the group consisting of a polymer of polycarboxylate, a sulfonated polystyrene polymer, a homopolymer or copolymer of vinylpyrrolidone, a polyalkoxylene glycol, and mixtures thereof. The present invention also comprises a method for treating hard surfaces wherein an acid liquid composition according to the present invention is applied in its pure form or in its diluted form, on said surfaces, and then it is allowed to act on said surfaces and then Remove by rinsing. In a broader embodiment, the present invention also comprises the use of a liquid acid composition comprising at least one acid (typically an organic or inorganic acid or a mixture thereof, as described hereinafter) and a acid stable polymer selected from the group consisting of a polycarboxylate polymer, a sulfonated polystyrene polymer, a vinylpyrrolidone homopolymer or copolymer, a polyalkoxylene glycol, and a mixture thereof, to remove limescale-containing stains from a hard surface, while the long-lasting gloss is provided to said surface after it has been first treated with said composition. In another, broader embodiment, the present invention comprises the use of a liquid acid composition comprising at least one acid (typically an organic or inorganic acid or a mixture thereof, as described hereinafter) and a polymer acid stable selected from the group consisting of a polycarboxylate polymer, a polypropylene polypropylene polymer, a homopolymer or copolymer of vinylpyrrolidone, a polyalkoxylene glycol, and mixtures thereof, suitable for removing limescale-containing stains from a hard surface, for reducing the formation of limescale deposits on said hard surface when brought into contact with water, after said hard surface has first been treated with said composition.

DETAILED DESCRIPTION OF THE INVENTION Liquid acid compositions The liquid compositions of the present invention are acid compositions. Accordingly, the compositions of the present invention are formulated at a pH below 5, preferably at 4, most preferably at a pH between 0 and 3, still more preferably at a pH between 0.1 and 2.5, still most preferably between 0.1 and 2.5. 2, and more preferably at a pH between 0.3 and 1.5. Liquid compositions according to the present invention are preferably aqueous compositions. Therefore, said compositions typically comprise from 50% to 98% by weight of the total water composition, preferably from 60% to 95% and more preferably from 70% to 90%. The compositions of the present invention comprise sulfamic acid as a first essential characteristic. The sulfamic acid can be added in the compositions according to the present invention in its acid form or as alkali metal salts thereof. Sulfamic acid can be added for example as sulfamate. Sulfamic acid is commercially available under the trade name Sulfamic acid by Albright & Wilson or Nissan chemicals. Accordingly, the compositions of the present invention comprise from 0.01% to 20% by weight of the total sulfamic acid composition, preferably from 0.1% to 10% and more preferably from 0.1% to 5%. The compositions according to the present invention comprise as a second essential characteristic a second acid or a mixture thereof. "Second acid" refers herein to any strong and / or weak organic or inorganic acid known to those skilled in the art with the exception of said sulfamic acid. In fact, said acids can be used in their acid form or in the form of their salts (mono-, di-, tri-) salts and in all their anhydrous, and hydrated forms, or mixtures thereof. Such acids can typically be used in the form of their alkali metal salts (eg, sodium salt, potassium salt, and the like) or their acid alkali hydrogen salts. The compositions according to the present invention are designed to remove limestones or stains comprising limestones as an essential component. In this way, the second acid is useful to strengthen the limestone scale removal performance of sulfamic acid. Preferably the second acids to be used herein that are particularly effective in removing limescale on several surfaces, have a first pKa not exceeding 5, most preferably not exceeding 3, and more preferably not exceeding 2. Examples of inorganic acids are the sulphonic acid derivatives, maleic acid (pKa = 1.83) hydrochloric acid (pKa <0), nitric acid (pKa <0), phosphoric acid (pKa = 2.1) and sulfuric acid (pKa = 0.4) . An example of organic acid is citric acid (pKa = 3.06). The second acids for removing limescale particularly suitable for use in accordance with the present invention are weak acids with pKa of 5 to 1.5, preferably 3 to 1.5, such as maleic acid. Maleic anhydride is equally suitable for use in the compositions according to the present invention. In fact, maleic anhydride is generally more economical than maleic acid and is transformed into the acid form when incorporated in an aqueous medium. Other suitable second acids are sulfonic acid derivatives including alkylsulfonic acids and arylsulfonic acids. Suitable aminosulfonic acids for use herein are linear or branched C 1 -C 6 alkylsulfonic acids or mixtures thereof, such as methanesulfonic acid ( pKa = 1.9) commercially available, for example from Aldrich, William Blythe & Co, Ltd. or Elf. Atochem.

The arylsulfonic acids suitable for use herein are in accordance with the formula: Where R-i, R2, R3, R and R5 are each H or SO3H, or straight or branched C- | C4 alkyl chain; or mixtures thereof. The preferred arylsuiphonic acids for use in the present invention are those which do not comprise or only have one alkyl chain. In fact, such arylsulfonic acids are particularly effective in removing limescale, which is not the case for their longer alkyl chain homologs. Likewise, said arylsulfonic acids are particularly safe for the surface treated therewith. Particularly suitable arylsulfonic acids for use herein are benzenesulfonic acid (pKa = 0.7), toluenesulfonic acid and cumene sulphonic acid. Among the previous three, at an equal weight%, the shorter the alkyl chain, until no chain is found, the better the removal performance of limestone inlays. Preferred second acids for use herein are maleic acid, sulfuric acid, arylsulfonic acids, alkylsulfonic acids, citric acid or mixtures thereof, and most preferred is maleic acid.

The compositions according to the present invention comprise from 0.01% to 45% by weight of the total composition of said second acid or a mixture thereof, preferably from 0.1% to 25%, more preferably from 1% to 20% and most preferably from 4% to 18%. The liquid acid compositions of the present invention comprise as a third essential characteristic an acid stable polymer selected from the group consisting of a polycarboxylate polymer, a sulfonated polystyrene polymer, a vinylpyrrolidone homopolymer or copolymer, a polyalkoxylene glycol, and mixtures thereof . "Stable acid" refers herein to the fact that the polymers according to the present invention allow the chemical parameters of the acid composition, ie, the pH of the composition and / or the acidity reserve, not to change when the composition It is stored in a rapid aging test (RAT) at 50 ° C for 6 days. Polycarboxylate polymers suitable for use herein are polymers comprising monomer units selected from the group consisting of unsaturated carboxylic acids such as acrylic acid, polycarboxylic acids, sulfonic acids, phosphonic acids and mixtures thereof. The copolymerization of the above monomer units between these or with other comonomers such as maleic anhydride, ethylene or propylene are also suitable. When maleic anhydride is used it acts as a source of additional carboxylic groups, while ethylene and propylene will act as diluents.

The molecular weight per carboxylate group of monomers containing a carboxylate group typically ranges from 20 to 200, preferably from 40 to 150, more preferably from 50 to 125. Preferred polymers for use herein have a total molecular weight of 2,000. to 4,500,000, preferably 10,000 to 4,000,000. Most preferred polymers for use herein contain from 0.5% to 4% by weight of an interlacing agent, wherein the interlacing agent tends to interconnect the linear fibers of the polymers to form the resulting interlaced products. Suitable interlacing agents include polyalkenyl polyethers. Preferred polycarboxylate polymers for use herein are polyacrylate polymers. Typically, acrylic-maleic acid-based copolymers can be used as a preferred polyacrylate polymer. Such materials include water-soluble salts of copolymers of acrylic acid and maleic acid. The average molecular weight of said copolymers in the acid form preferably ranges from about 2,000 to 1,000,000, more preferably from about 5,000 to 100,000, more preferably from about 10,000 to 80,000. The ratio of acrylate to maleate segments in said copolymers will generally vary from about 30: 1 to about 1: 1, more preferably from about 10: 1 to 2: 1. The water-soluble salts of said copolymers of acrylic acid / maleic acid may include, for example, alkali metals, ammonium salts and substituted ammonium salts. Acrylate / maleate copolymers of said type are known materials which are described in European Patent Application No. 66915, published on December 15, 1982. Particularly preferred is a maleic acid / acrylic acid copolymer with an average molecular weight of approximately 70,000. Such copolymers are commercially available from BASF under the trade name Sokalan CP5®. Other preferred polyacrylate polymers are the copolymer of acrylic acid and alkylacrylate (C5-C10), commercially available under the tradename Carbopol® 1623, Carbopol® 695 from BF Goodrich. Commercially available polymers of the polyacrylate type also include those sold under the tradenames Carbopol®, Acrysol® Polygel®, and Sokalan®. Two different types of sulfonated polystyrene polymers are useful herein. The first type is a sulfonated styrene homopolymer. The second type is a sulfonated styrene interpolymer with ethylenically unsaturated comonomer. The compounds useful herein include the partially or fully neutralized salts of the sulfonated polystyrene or the sulfonated styrene interpolymers., ie, the soluble salts of said polymers, wherein the sulfonic acid groups are partially or completely neutralized. Suitable ethylenically unsaturated comonomer units which can be copolymerized with styrene so that the interpolymers are suitable for sulfation include acrylic and methacrylic esters of aliphatic alcohols such as methyl, ethyl, butyl and 2-ethyl hexyl alcohols, acrylic acid, acrylonitrile, methacrylonitrile , dibutyl maleate, vinylidene chloride and the like. Particularly preferred ethylenically unsaturated monomers for use herein include ethylene, propylene, styrene, vinyl naphthalene, acrylic acid and maleic anhydride. Sulfonated styrene homopolymers suitable for use herein are commercially available under the trade name Versaflex® from National Starch. The most suitable polymers and copolymers for use herein will be water soluble, and the molecular weight of such polymers is preferably 5,000 and 10,000,000, more preferably between 50,000 and 1,000,000. The vinylpyrrolidone homopolymers suitable for use herein are homopolymers of N-vinylpyrrolidone having the following repeating monomer: wherein n (degree of polymerization) is an integer of 10 to 1,000,000, preferably 20 to 100,000 and more preferably 20 to 10,000. Accordingly, suitable vinylpyrrolidone homopolymers ("PVP") for use herein have an average molecular weight of from 1,000 to 100,000,000, preferably 2,000 to 10,000,000, more preferably from 5,000 to 1,000,000, and more preferably from 50,000 to 500,000. Suitable vinylpyrrolidone homopolymers are commercially available from ISP Corporation, New York, NY and Montreal, Canada under the product names PVP K-15® (viscosity molecular weight 10,000) PVP K-30® (average molecular weight 40,000) , PVP K-60® (average molecular weight of 160,000), and PVP K-90® (average molecular weight of 360,000). Other suitable vinylpyrrolidone homopolymers are commercially available from BASF Cooperation include Sokalan HP 165® and Sokalan HP 12®; vinylpyrrolidone homopolymers known to those skilled in the detergent field (see for example EP-A-262,897 and EP-A-256,696). Suitable copolymers of vinylpyrrolidone for use herein include copolymers of N-vinylpyrrolidone and alkylenically unsaturated monomers or mixtures thereof. The alkylenically unsaturated monomers of the copolymers herein include unsaturated dicarboxylic acids such as maleic acid, chloromaleic acid, fumaric acid, itaconic acid, citraconic acid, phenylmaelic acid, aconitic acid, acrylic acid, N-vinylmidazole and vinyl acetate. Any of the anhydrides of the unsaturated acids, for example, acrylate, methacrylate, can be used. Aromatic monomers such as styrene, sulfonated styrene, alpha-methylstyrene, vinyltoluene, t-butylstyrene and similar known monomers can be used. The molecular weight of the vinylpyrrolidone copolymer is not especially critical insofar as the copoiimer which is soluble in water has some surface activity and is adsorbed on the hard surface of the composition or liquid solution (ie, under dilute use conditions). ) comprising it in such a way as to increase the hydrophilic character of the surface. However, the preferred copolymers of N-vinylpyrrolidone and alkylenically unsaturated monomers or mixtures thereof, have a • Molecular weight between 1,000,000 and 1,000,000 preferably between 10,000 and 500,000 and more preferably between 10,000 and 200,000. For example, the polymers of N-vinylimidazole N-vinylpyrrolidone particularly suitable for use herein have an average molecular weight in the range of 5,000-1,000,000, preferably from ,000 to 500,000, and most preferably 10,000 to 200,000. The scale of • average molecular weight was determined by light scattering as described in Barth H.G and Mays J.W. Chemical Analysis. Vol 1 13, "Modern Methods of Polymer Characterization". Said copolymers of N-vinylpyrrolidone and monomers Alkyleneically unsaturated such as PVP / vinyl acetate copolymers are commercially available under the tradename Luviskol®, BASF series.

The vinylpyrrolidone copolymers for use in the compositions of the present invention also include quaternized or non-quaternized vinylpyrrolidone / dialkylaminoalkylacrylate or methacrylate copolymers. Said copolymers of vinylpyrrolidone / dialkylaminoalkylacrylate or methacrylate (quaternized or non-quaternized) suitable for use in the compositions of the present invention are according to the following formula: .X " wherein n is between 20 and 99 and preferably between 40 and 90 mol% and m is between 1 and 80 and preferably between 5 and 40 mol%; R-i represents H or CH 3; and denotes 0 or 1; R2 is -CH2-CHOH-CH2- or CXH2X) wherein x = 2 to 18; R3 represents a lower alkyl group of 1 to 4 carbon atoms, preferably methyl or ethyl, or R denotes a lower alkyl group of 1 to 4 carbon atoms, preferably methyl or ethyl; X "is selected from the group consisting of Cl, Br, I, 1 / 2SO, HSO4 and CH3SO3 The polymers can be prepared by the process described in French patents Nos. 2,077,143 and 2,393,573 The copolymers of vinylpyrrolidone / dialkylaminoalkylacrylate or Preferred quaternized or non-quaternized methacrylates for use herein have a molecular weight of between 1,000 and 1,000,000, preferably between 10,000 and 500,000, and most preferably between 10,000 and 100,000. Said vinylpyrrolidone / dialkylaminoalkylacrylate or methacrylate copolymers are commercially available under the name of copolymer 845®, Gafquat 734®, or Gafquat 755® from ISP Corporation, New York, NY and F Montreal, Canada or BASF under the trade name Luviquat®. Suitable polyalkoxylene glycols for use herein have the following formula: HO- (CH2-CHRO) nH, wherein R is hydrogen or a straight or branched hydrocarbon chain having from 1 to 30 carbon atoms, preferably R is hydrogen, or a linear or branched alkyl group, alkenyl group or aryl group having from 1 to carbon atoms, more preferably 1 to 16, even more preferably 1 to 8, and more preferably R2 is methyl, or hydrogen. Preferably n is an integer from 5 to 1000, more preferably from 10 to 100, even more preferably from 25 to 60 and most preferably from 30 to 50. Preferred polyalkoxylene glycols for use in accordance with the present invention have a molecular weight of at least 200, more preferably 400 to 5000 and most preferably from 800 to 3000. Preferred polyalkoxylene glycols are polyethylene glycols similar to polyethylene glycol (MW 2000). Preferred acid-stable polymers to be used herein are the sulfonated polystyrene polymers and / or the vinylpyrrolidone homopolymers. It has been surprisingly discovered that when the acid-stable polymers described herein are added to the liquid acid composition they comprise sulphamic acid and another acid provides improved skin smoothness and improved gloss, although they do not understand the performance to remove limestone scale. said composition. Advantageously, said benefits are obtained at low levels of acid-stable polymers, thus it is yet another advantage of the present invention to provide the desired benefits at low cost. Typically, the liquid acid compositions according to the present invention comprise from 0.001% to 5% by weight of the total composition of an acid stable polymer or mixtures thereof, preferably from 0.002% to 2%, more preferably from 0.01% to 2% and most preferably from 0.01% to 1%. Although one does not wish to be limited by theory, it has been observed that hard surfaces often have low affinity with water. The foregoing means that, when the water comes into contact with the hard surfaces, its dispersion, which is controlled by the interfacial energy (i.e., solid / liquid surface tension), is very limited. In fact, it has been observed that the most stable configuration for water is the grouping into spherical droplets instead of forming a thin film dispersed evenly over the surface. Then, as the water droplets evaporate, their salt content becomes progressively higher and higher, so that the carbonate salts precipitate, eventually resulting in watermarks or even deposits of limescale. The final result is a reduction in surface brightness. It has been found that when the acid-stable polymers, as described herein, are added to the liquid acid compositions, a hydrophilic layer is left on a hard surface treated therewith, said hydrophilic layer allows the water to become contact with the surface that has been treated first in this manner (ie, the water that was used to rinse the surfaces having been treated in this manner) is uniformly dispersed on the surface ("laminating effect") rather than forming drops. In this way, the formation of water marks and / or limescale deposits during drying is reduced or even eliminated.

Furthermore, it has surprisingly been found that the acid-stable polymers of the present invention not only have the ability to adhere to a surface treated with the acid compositions of the present invention comprising the same, but still remain adhered to the surface even. after several rinse cycles (for example, when the water reaches said surface later in, for example, a sink during daily domestic operation), thus providing long-lasting protection against the formation of watermarks and / or deposition of deposits of limestones, thus prolonging the duration of the shiny surfaces. In a broader embodiment, the present invention comprises the use of a liquid acid composition comprising at least one acid or a mixture thereof, typically an organic or inorganic acid or a mixture thereof and an acid stable polymer, as described herein, suitable for removing limescale-containing stains from a hard surface, to reduce the formation of limescale deposits on said hard surface when contacted with water, after said hard surface has been treated first with said composition. In another broad embodiment, the present invention further comprises the use of said acid composition to remove limescale-containing stains from a hard surface, wherein the long-lasting shine is provided to said surface after it has been first treated with said surface. composition.

Without being limited by theory, it is believed that acid stable polymers also have the ability to form a film on the user's skin surface, contributing to the skin softness characteristics provided due to the presence of sulfamic acid in the skin. top of another acid otherwise perceived to be more irritating to the skin, ie, maleic acid. An additional advantage related to the use of the acid-stable polymers of the present invention is that, as they adhere to the hard surface, making them more hydrophilic, the same surfaces become smoother (the foregoing can be perceived by touching said surface) and this contributes to perceiving a surface whose limestone inlays have been perfectly eliminated.

Optional ingredients The compositions according to the present invention may further comprise a variety of other ingredients, including surfactants, colorants, bactericides, thicknesses, colorants, chelators, pigments, solvents, stabilizers, perfumes, corrosion inhibitors and the like.

Surfactants A highly preferred optional ingredient suitable for use in the compositions of the present invention is a surfactant or a mixture thereof. Surfactants are desired herein because they contribute to the cleaning benefits of the limestone scale removing compositions of the present invention. In fact, the presence of a surfactant allows to increase the cleaning of the greasy soap impurity layer of the compositions herein. More generally, the presence of a surfactant in the liquid acid compositions according to the present invention makes it possible to reduce the surface tension and improve the wettability of the surfaces being treated with the liquid acid compositions of the present invention. The presence of a surfactant or a mixture thereof in the liquid acid compositions of the present invention helps to solubilize the soils. Accordingly, the compositions according to the present invention may comprise a surfactant or a mixture thereof. The compositions according to the present invention can comprise up to 40% by weight of the total composition of said surfactant or a mixture thereof, more preferably from 0.05% to 15%, even more preferably from 0.1% to 10%, and more preferably from 0.1% to 5%. All types of surfactants can be used in the present invention, including nonionic, anionic, zwitterionic or amphoteric surfactants. It is also possible to use mixtures of said surfactants without departing from the spirit of the present invention.

The highly preferred surfactants which are used herein are zwitterionic surfactants. In fact, these have the ability, when added to the acid compositions of the present invention, to maintain the development of limescale removal from the acidic system (i.e., development of similar limescale removal in comparison with the same acid compositions). , but without any surfactant), while providing the excellent cleaning ability of greasy soap impurity layer to the compositions of the present invention. Suitable surfactants and zwitterionics which are used herein contain basic and acidic groups that form an internal salt, giving the cationic and anionic hydrophilic groups in the same molecule at a relatively broad scale of pHs. The typical cationic group is a quaternary ammonium group, although other positively charged groups such as the phosphonium, imidazolium and sulfonium groups can be used. Typical anionic hydrophilic groups are carboxylates and sulfonates, although other groups such as sulfates, phosphonates and the like can be used. A generic formula for the preferred zwitterionic surfactants for use herein (ie, betaine and / or sulfobetaine) is R1-N + (R2) (R3) R4X "wherein Ri is a hydrophobic group; R2 is hydrogen, Ci-Cβ, hydroxyalkyl or other alkyl group of R 3 is hydroxyalkyl alkyl or another substituted C 1 -Cd alkyl group which can also be attached to R 2 to form ring structures with N, or a carboxylic acid group of CI-CT or a sulfonate group of Ct-Cβ; R4 is a moiety joining the cationic nitrogen atom to the hydrophilic group and is typically an alkylene, hydroxyalkylene or polyalkoxy group containing from 1 to 10 carbon atoms, and X is the hydrophilic group which is a carboxylate or sulphonate group, preferably sulfonate group Preferred hydrophobic groups R ^ are aliphatic or aromatic hydrocarbon chains, saturated or unsaturated, substituted or unsubstituted which may contain linking groups such as upos amido, ester groups. The most preferred R-i is an alkyl group containing from 1 to 24 carbon atoms, preferably from 8 to 18, and more preferably from 10 to 16. Said simple alkyl groups are preferred for reasons of cost and stability. However, the hydrophobic group Ri can also be an amido radical of the formula Ra-C (O) -NRb- (C (Rc) 2) m, where Ra is an aliphatic or aromatic hydrocarbon chain, saturated or unsaturated, substituted or unsubstituted containing from 8 to 20 carbon atoms, preferably an alkyl group containing from 8 to 20 carbon atoms, preferably up to 18, more preferably up to 16, Rb is a hydrogen or a short alkyl or substituted alkyl chain containing from 1 to 4 carbon atoms, preferably a group selected from the group consisting of methyl, ethyl, propyl, ethyl or hydroxy substituted propyl and mixtures thereof, more preferably methyl or hydrogen, Rc is selected from the group consisting of of hydrogen and hydroxy groups, and m is from 1 to 4, preferably from 2 to 3, more preferably 3, with no more than one hydroxy group in any portion (C (Rc) 2). The preferred R 2 is hydrogen, or an alkyl or substituted alkyl containing from 1 to 4 carbon atoms, preferably a group selected from the group consisting of methyl, ethyl, propyl, ethyl or hydroxy substituted propyl and mixtures thereof, more preferably methyl. The preferred R3 is a C-α-C4 carboxylic acid group, a C1-C4 sulfonate group, or an alkyl or substituted alkyl containing from 1 to 4 carbon atoms, preferably a group selected from the group consisting of methyl , ethyl, propyl, ethyl or hydroxy substituted propyl and mixtures thereof, more preferably methyl. The preferred R 4 is (CH 2) n wherein n is an integer from 1 to 10, preferably from 1 to 6, more preferably is from 1 to 3. Some common examples of betaine / sulfobetaine are described in U.S. Patent Nos. 2,082,275, 2,702,279 and 2,255,082, incorporated herein by reference. Examples of particularly suitable alkyldimethylbetaines include cocodimethylbetaine, lauryldimethylbetaine, decildimethylbetaine, 2- (N-decyl-N, N-dimethyl-ammonia) acetate, 2- (N-coconut N, N-dimethylammonium) acetate, myristyldimethylbetaine, palmityldimethylbetaine, cetyldimethylbetaine, stearyldimethylbetaine. . For example, cocodimethylbetaine is commercially available from Seppic under the trade name of Amonyl 265®. Laurylbetaine is commercially available from Albright & amp;; Wilson under the trade name Empigen BB / L®.

Another example of betaine is lauryl imino dipropionate commercially available from Rhone-Polulenc under the trade name Mirataine H2C-HA®. Particularly preferred zwitterionic surfactants for use in the acid compositions of the present invention are the sulphobetaine surfactants as they provide optimal limescale removal benefits and soap impurity layer cleaning benefits. Examples of particularly suitable sulfobetaine surfactants include bis (hydroxyethyl) sulphobetaine, cocoamido propylhydroxysulfobetaine bait which are commercially available from Rhone Poulenc and Witco, under the trade name of Mirataine CBS® and Rewoteric AM CAS 15® respectively. Other examples of amidobetaine / amidosulfobetaine include cocoamidoethylbetaine, cocoamidopropylbetaine or acylamidopropylene (hydropropylene) sulfobetaine C10-C14 fat. For example, acrylamidopropylene (hydropropylene) suiphobetaine C10-C14 fat is commercially available from Sherex Company under the tradename "Varion CAS® sulfobetaine". Suitable amine oxides for use herein are according to the following formula R 1 R 2 R 3 NO wherein each of R 1, R 2 and R 3 is independently a saturated or unsaturated, substituted or unsubstituted, straight or branched alkyl group containing from 1 to 30 carbon atoms, and preferably from 1 to 20 carbon atoms. Particularly preferred amine oxides for use in accordance with the present invention are amine oxides having the following formula R-? R2R3NO, in • wherein R1 is a saturated or unsaturated, substituted or unsubstituted, straight or branched alkyl group containing from 1 to 30 carbon atoms, preferably from 8 to 20 carbon atoms, more preferably from 6 to 16, more preferably from 8 to 14, and wherein R2 and R3 are independently substituted or unsubstituted, linear or branched alkyl groups containing from 1 to 4 carbon atoms, preferably from 1 to 3 carbon atoms, and Most preferably they are methyl groups, or mixtures thereof. Amine oxides suitable for use herein are, for example, cocodimethylamine oxides, C12-C16 dimethylamine oxides. Said amine oxides may be commercially available from Hoechst, Stephan, AKZO (under the trade name Aromox®) or FINA (under the trade name Radiamox®). Suitable amines for use herein are, according to the following formula RR'R "N, wherein R is a saturated or unsaturated, substituted or unsubstituted, straight or branched alkyl group containing from 1 to 30 carbon atoms, and preferably from 1 to 20 atoms of And wherein R 'and R "are independently saturated or unsaturated, substituted or unsubstituted, linear or branched alkyl groups containing from 1 to 30 carbon atoms or hydrogen, Particularly preferred amines to be used in accordance with the present invention are amines having the following formula, RR'R "N, wherein R is a saturated or unsaturated, straight or branched alkyl group containing from 1 to 30 carbon atoms, preferably from 8 to 20 carbon atoms , more preferably from 6 to 16, more preferably from 8 to 14 and wherein R 'and R "are independently substituted or unsubstituted, linear alkyl groups containing from 1 to 4 carbon atoms, preferably from 1 to 3 carbon atoms , and more preferably are methyl groups or mixtures thereof Amines suitable for use herein are for example, C12 dimethylamine, coconut dimethylamine, C12-C16 dimethylamine Said amines may be commercially available available from Hoechst under the trade name Genamin® AKZO under the trade name of Aromox® or Fina under the trade name of Radiamine®. The quaternary ammonium surfactants suitable for use herein are, according to the formula R-i R2R3R4N + X-, wherein X is a counter anion such as halogen, methylisulfate, methylsulfonate, or hydroxide, Ri is a linear or branched substituted or unsubstituted saturated or unsaturated alkyl group containing from 1 to 30 carbon atoms, preferably from 12 to 20, more preferably from 8 to 20 and R2, R3 and R4 are independently hydrogen, or saturated or unsaturated, substituted or unsubstituted, linear or branched alkyl groups containing from 1 to 4 carbon atoms, preferably from 1 to 3 and more preferably methyl . In the highly preferred quaternary ammonium surfactants in the present Ri is a C? 0-C18 hydrocarbon chain, more preferably C-? 2, C14, or C-? 6 and R2, R3 and R4 are methyl, and X is halogen, preferably bromine or chlorine, most preferably bromine. Examples of quaternary ammonium surfactants are myristyl trimethylammonium methylisulfate, cetyl trimethylammonium methylisulfate, lauryltrimethylammonium bromide, stearyltrimethylammonium bromide (S ), cetyl trimethylammonium bromide (C ), and myristyltrimethylammonium bromide (M ). The highly preferred herein are the lauryl trimethylammonium salts. Said quaternary trimethylammonium surfactants may be commercially available from Hoechst, or Albright & amp;; Wilson under the trade name of Empigen CM®. In a preferred embodiment, the surfactant used in the acid compositions of the present invention is a surfactant system comprising a zwitterionic surfactant with a second surfactant, ie an amine and / or amine oxide and / or surfactant of quaternary ammonium as described herein in a weight ratio of the surfactant and zwitterionic to the second surfactant of at least 1: 1, preferably at least 2: 1. Said surfactant system provides the acid compositions according to the present invention with an optimal limescale removal development (eg, comparable to the development of limestone scale removal of the same compositions without any surfactant) as well as a performance Optimal soap impurities layer cleaning.

Suitable nonionic surfactants for use herein are the alkoxylated alcohol nonionic surfactants which can be readily made by condensation processes which are well known in the art. However, a wide variety of said alkoxylated alcohols, especially ethoxylated and / or propoxylated alcohols is also commercially available in a convenient manner. Surfactant catalogs are available, which list a number of surfactants, including nonionics. Consequently, the preferred alkoxylated alcohols for their The use herein are nonionic surfactants according to the formula RO (E) e (P) pH wherein R is a hydrocarbon chain of 2 to 24 carbon atoms, e is ethylene oxide and p is oxide of propylene, yeyp representing the average degree of, exylation and propoxylation respectively, are from 0 to 24. The hydrophobic portion of the non-ionic compound may be a primary or secondary, straight or branched alcohol having from 8 to 24 carbon atoms. The preferred nonionic surfactants for use in the compositions according to the invention are the condensation products of ethylene oxide with alcohols having a straight alkyl chain, ranging from 6 to 22 carbon atoms, wherein the degree of ethoxylation is of. 1 to 15, preferably 5 to 12. Such suitable nonionic surfactants are commercially available from Shell, for example, under the tradename Dobanol® or from Shell under the tradename Lutensol®. Such nonionic surfactants are preferred because they have been found to have stable product formulation without requiring the addition of stabilizers or hydrothopes. Suitable alkyl sulfonates after use herein include water soluble salts or acids of the formula RSO3M, wherein R is a linear or branched, saturated or unsaturated C6-C2o alkyl group, preferably an alkyl group of C-? 2-C18 and more preferably a C14-C16 alkyl group, and M is H or a cation, i.e., an alkali metal cation (ie, sodium, potassium, lithium), or ammonium or substituted ammonium (i.e. methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethylammonium cations and dimethylpiperidinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and similar). Alkylarylsulfonates suitable for use herein include water soluble salts or acids of the formula RSO3M, wherein R is an aryl, preferably a benzyl, substituted by a linear or branched, saturated or unsaturated C6-C2o alkyl group, preferably an alkyl group of C-? 2-Ci8 and more preferably an alkyl group of C-C16, and M is H or a cation, i.e., an alkali metal cation (eg, sodium, potassium, lithium, calcium , magnesium, etc.) or ammonium or substituted ammonium (eg, methyl-, dimethyl- and trimethylammonium cations and quaternary ammonium cations, such as tetramethyl ammonium and dimethylpiperidinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).

"Alkyl of secondary C6-C2o or C6-C2o alkylarylsulfonates", herein refers to the formula as defined above, the group SO3M or aryl-SO3M is bonded to a carbon atom and the alkyl chain is placed between two other carbons of said alkyl chain (carbon atom). secondary carbon). An example of C14-C16 alkylsuifonate is Hostapur® SAS available from Hoechst. An example of commercially available alkylarylsulfonate is laurylaryl sulfonate from Su.Ma. Particularly preferred alkylarylsulfonates are alkylbenzene sulphonates commercially • 10 available under the trade name Nansa® available from Albright & Wilson. The alkyl sulfate surfactants suitable for use herein are in accordance with the formula R-tSO M, wherein R-i represents a hydrocarbon group selected from the group consisting of linear or branched alkyl radicals containing from 6 to 20 carbon atoms. carbon and alkylphenyl radicals containing from 6 to 15 carbon atoms in F the alkyl group. M is H or a cation, that is, an alkali metal cation (ie, sodium, potassium, lithium, calcium, magnesium, etc.) or ammonium or substituted ammonium (ie, methyl-, dimethyl-, and trimethylammonium cations and quaternary ammonium cations, such as tetramethylammonium and dimethylpiperidinium cations and quaternary ammonium cations derived from the aicylamines such as ethylamine, diethylamine, triethylamine and mixtures thereof, and the like). Suitable alkoxylated alkylsulphate surfactants for use herein are according to the formula RO (A) mSO3M, wherein R is an unsubstituted C6-C2o alkyl or hydroxyalkyl group having a C6-C2o alkyl component, preferably an alkyl or hydroxyalkyl of (C 2 -C 2), more preferably C 2 -C 8 alkyl or hydroxyalkyl, A is an ethoxy or propoxy unit, m is greater than zero, typically between about 0.5 and about 6, more preferably between about 0.5 and about 3, and M is H or a cation which may be, for example, a metal cation (ie, sodium, potassium, lithium, calcium, magnesium, etc.), cation Ammonium or substituted ammonium The alkyl ethoxylated sulfates as well as the alkylpropoxylated sulphates are contemplated in present. Specific examples of substituted ammonium fractions include methyl-, dimethyl-, trimethylammonium and quaternary ammonium cations, such as tetramethylammonium cations, dimethylpiperidinium and cations derived from alkanolamines such as ethylamine, diethylamine, triethylamine, mixtures thereof, and the like. Examples of surfactants are alkyl sulfate polyethoxylated (1.0) of C12-C18, C? 2-C? 8E (1.0) M), polyethoxylated alkyl sulfate (2.25) of Ci2-C? 8f C12-C? 8E (2.25) M), polyethoxylated alkyl sulfate (3.0) of C 2- C-is, C- | 2-C- | 8E (3.0) and polyethoxylated alkyl sulfate (4.0 ) of C-? 2-C18, C? 2- C? 8E (4.0) M), wherein M is conveniently selected from sodium and potassium. The diphenyl oxide disulfonate surfactants Linear or branched alkylalkoxylated C6-C2o suitable for use herein, are according to the following formula: Wherein R is a linear or branched, saturated or unsaturated alkyl group of C6C20, preferably a C? 2-C? 8 alkyl group, and more preferably an alkyl group of C-Cie, and X + is H or a cation , that is, an alkali metal cation (ie, sodium, potassium, lithium, calcium, magnesium, etc.). The linear or branched diphenyl oxide disulfonate surfactants Particularly suitable C 1 -C 2 alkylalkoxylates for use herein are branched diphenyl oxide acid of C 12 and sodium salt of linear diphenyl oxide of C 16 respectively, commercially available from DOW under the trade name Dowfax 2A1 ® and Dowfax 8390®. Other anionic surfactants useful herein include salts (including, for example, sodium, potassium, ammonium and substituted ammonium salts such as mono-, di- and triethanolamine salts) of soap, C8-C24 olefinsulfonates, polycarboxylic acids sulphonates prepared by sulfonation of the pyrolyzed product alkali metal citrates terreo, that is, as described in British Patent Specification No. 1, 082, 179, C8-C24 alkyl polyglycol ether sulphates (containing up to 10 moles of ethylene oxide); Alkylethersulfonates such as C14-? 6 methyl ester sulfonates; acylglycerol sulfonates, fatty oleyl glycerol sulfates, alkyl phenol ethylene oxide ether sulfates, alkyl phosphates, isethionates such as acylisethionates, N-acyltaurates, alkylsuccinamates and sulfosuccinates, sulfosuccinate monoesters (especially saturated and unsaturated C-? 2-C? 8 monoesters) ), sulfosuccinate diesters (especially saturated and unsaturated C6-C diesters), acyl sarcosinates, alkylpolysaccharide sulfates such as alkylpolyglucoside sulfates (the non-sulphonated nonionic compounds described below), alkylpolyethoxycarboxylates such as those of the formula RO ( CH2CH2O) k CH2COO-M \ wherein R is a C8-C22 alkyl, k is an integer from 0 to 10, and M is a soluble salt formation cation. Resin acids and hydrogenated resin acids are also suitable, such as rosin, hydrogenated rosin, and hydrogenated resin acids and resin acids present or derived from tallow oil. Other examples are provided in "Surface Active Agents and Detergents" (Vols. I and II by Schwartz, Perry and Berch). A The variety of such surfactants is also generally described in the US patent. 3,929,678, issued December 30, 1975 to Laughlin et al. In column 23, line 58 to column 29, line 23. Preferred anionic surfactants herein include the primary and secondary C6-C20 alkyl sulfonates and the C6-C20 primary and secondary alkylarylsulfonates, or a mixture thereof.

Dyes The liquid compositions according to the present invention can be colored. Accordingly, these may comprise a colorant or a mixture thereof. Suitable colorants for use herein are acid stable dyes. "Stable in acid" refers herein to a compound that is chemically and physically stable in the acidic environment of the compositions herein. Suitable colorants for use herein include phthalocyanine dyes of a or b and / or metal trimethylmethane. The a or β-metal phthalocycline dyes suitable for use in the compositions of the present invention are organic pigments constant to light with four isoindol groups, (C6H4) C2N, linked by four nitrogen atoms to form a conjugated chain.

Its general structure is as follows: twenty wherein the substituent X can be one of the following groups: H, Cl, r > HSO3, COO-M +, Br, NO2, OCH3 or a C1 to C10 alkyl group, and wherein Me is copper, chromium, vanadium, magnesium, nickel, platinum, aluminum, cobalt, lead, barium or zinc. Phthalocyanine dyes of metal a or ß to be used in the present are copper a or β phthalocyanine dyes.

Examples of such copper phthalocyanine dyes a for used in the present are copper phthalocyanine (X = H, blue color) commercially available under the name UNISPERSE Blue B-E® from Ciba-Geigy, or Cosmenyl blue A2R® from Hoechst, or Pigmasol blue 6900® from BASF, • 10 or chlorinated copper phthalocyanine (X = CI, green color) commercially available under the name Pigmasol Green 8730® from BASF. Examples of trimethylmethane dyes are commercially available from Hoescht under the name Vitasyn® or from BASF under the name Acid Blue®.

Typically the compositions of the present invention may • comprising up to 0.2% by weight of the total composition, of a colorant or a mixture thereof, preferably from 0.0001% to 0.015%, and more preferably from 0.001% to 0.010%.

Packaging Form of the Liquid Acid Compositions The liquid acid compositions of the present invention can be packaged in a variety of suitable detergent packages known to those skilled in the art.

Another advantage of the present invention is that the acid liquid compositions of the present invention comprising the acid system and the acid stable polymer herein can be easily dispersed on the surface to be treated through a spray type supplier such as 5 a drive sprinkler. Accordingly, the present invention also comprises liquid compositions of the invention packaged in a spraying supplier, preferably a spray sprayer supplier in a rubber spraying supplier. Spray type suppliers to be used for F 10 according to the present invention include manually operated foam drive type suppliers laid for example by Specialty Packaging Products, Inc. or Continental Sprayers, Inc. Such types of suppliers are described, for example, in US-4,701, 311 a Dunning and others, and US-4,646,973 and US-4,538,745 both to Focarracci. Particularly < W 15 preferred for use herein as spray type suppliers such as T 8500® or T 8900® commercially available from Continental Spray International or T 8100® commercially available from Canyon, Northen Ireland. In said supplier, the liquid composition is divided into fine liquid levels resulting in a spray that is directs to the surface to be treated. In fact, in said composition-type spray dispenser contained in the body of said supplier is directed through the spray head supplier head through the energy communicated to a pumping mechanism by the user in accordance with this active said pumping mechanism. More particularly, in said spray-type dispenser head, the composition is forced against an obstacle, i.e. a grating or a cone or the like, thereby providing impacts to help atomize the liquid composition, i.e. formation of liquid drops. A further advantage of the present invention is that the liquid liquid compositions of the present invention can be applied uniformly over a relatively large area of a surface to be treated by a sprayer-type spout, thereby ensuring improved development of limestone scale removal and improved development of greasy suds cleaning. Process for treatment surfaces The compositions according to the present invention are particularly suitable for treating hard surfaces soiled by spots containing limestones. "Stains containing limestones" refers here to any dirt from pure limestones, that is, any dirt composed essentially of mineral deposits as well as to stains containing limestones typically found, for example, in a kitchen or in a bath, ie, stains that contain not only mineral deposits such as calcium carbonate and / or magnesium but also suds (eg, calcium stearate) and other fats (eg, body fat). The compositions of the present invention show an excellent development of limestone scale removal when they are used to treat any type of surfaces stained by limestones containing limescale comprising not only deposit of limestones pure but also at least 10% by weight of the total dirtiness of organic deposits such as suds and grease, preferably more than 30%. Such surfaces can be found in bathrooms, kitchens, and also in applications that include large applications such as automatic dishwashers and / or washing machines. Accordingly, the present invention comprises a process for treating hard surfaces stained by limescale-containing stains wherein an aqueous acidic liquid composition according to the present invention is applied in its pure form or in its diluted form, on said surfaces, and then let it act on said surfaces and then remove it by rinsing. The term "used in diluted form" herein includes dilution by the user. Typical dilution levels are from 0.5 to 50% by weight of the composition. The term "treatment" includes the removal of limescale deposits, as they are safe for the treated surfaces and optionally the cleaning of greasy soaps, especially when surfactants are present.

Limestone scale removal development test method The limescale removal ability of a composition according to the present invention can be evaluated by soaping a block of marble (the marble blocks are, chemically speaking, very similar to the limestones, that is to say, are essentially made of calcium carbonate) in 20 g of said composition. The marble is weighed before and after the experiment, and the development is expressed in grams of marble block dissolved over time. Alternatively, the development of limestone scale removal can also be evaluated during the detection of CO2 release.

Greasy suds cleaning development test method In this test method, the white enamel tiles (typically 24 cm x 4 cm) were coated with typical greasy soaps, mainly based on calcium stearate and commercially available artificial body filings (eg, 0.3 grams with a spray). The soiled tiles were then dried in an oven at a temperature of 140 ° C for 30 minutes and then aged overnight at room temperature (approximately 15 ° C-20 ° C). Then, the dirty tiles were treated with a Spontex® sponge impregnated with the liquid acid composition of the present invention (ie, 5 grams). The ability of the composition to remove the greasy suds was measured by the number of drops needed to perfectly clean the • *. surface. The lower the number of strokes, the greater the capacity for cleaning the composition's oily suds.

Brightness test method Obtaining a good final gloss result resulted from a good dispersion of a liquid composition on the surface when the surface was treated with it and the reduced formation of watermarks and reduced precipitation of the poorly soluble salts in water when the water was evaporated. The ability of a composition to provide "gloss" to the surfaces refers to the ability of the composition to leave no watermarks after evaporation of the water. The above could be evaluated through visual evaluation. 15? N a suitable test method, two rectangular areas (10 cm x 4 cm) of a sink (made of stainless steel or ceramic) were treated with a composition according to the present invention and a reference composition, for example, the same composition but without said polymer. First, 3 grams of composition were poured into each of the surfaces to be treated and then rubbed (10 strokes) using Spontex® sponge. Then, each treated surface was rinsed with 200 grams of tap water and dried. Subsequently, the treated surfaces were dried with the compositions according to the present invention and those treated with the reference composition, these were compared from side to side and evaluated by visual evaluation to evaluate the difference in brightness. The evaluation could generally be done by applying the panel rating unit (PSU). In a long-lasting gloss test method, said test method could be carried out as mentioned above, but the rinse and dry cycle was repeated several times. Each time, after the two surfaces were dried, they were compared from side to side and evaluated by visual evaluation to see the difference in brightness. The evaluation was generally done by applying the panel rating unit (PSU). The present invention is further illustrated by the following examples.

EXAMPLES Said compositions were made by comprising the ingredients listed in the proportions listed (% by weight).

III IV V VI Disobedient:? (% by weight) - '£ Maleic acid 10 10 - - _ 10 Sulfamic acid 2 2 2 2 2 2 Citric acid - - 2 2 2 2 Mirataina CBS® 2.0 2.0 - 2.0 - 2.0 Rewoteric AM CAS - - - - - - 15® (*) HLAS (**) - - - - 0.50 - Sulphate Polystyrene 0.03 0.01 0.05 0.03 0.04 0.05 Water and minor ingredients • up to 100 vile VIII IX XI XII Inheritors: 10 (% by weight) • Maleic acid 8 10 12 ^ _. Sulfamic acid 2 2 2 2 2 2 Citric acid - 1 - 6 6 8 Mirataina CBS® - - - - - - Rewoteric AM CAS 2 - 2 - - 2.2 ® HLAS (*) - - - - 0.50 - Polyvinylpyrrolidone 0.03 0.05 0.05 0.06 0.05 0.05 Water and minor ingredients - up to 100 fifteen XIII XIV XV XVI XVII XVIII Ingredients: (% by weight) Maleic acid 10 - - - 10 Sulfamic acid 2 1 2 2 2 Citric acid - 1 6 6 - Mirataina CBS® 1 20 Rewoteric AM CAS - 1 - - 2.2 ® Polyethylene glycol 1.05 - - 0.50 0.1 (MW 2000) Sokalan CP5® 0.05 _ 0.05 0.1 _ _ Water and minor ingredients up to 100 The Mirataine CBS® and Rewoteric AM CAS® 15 are r > cocoamidopropyl hydroxysulfobetaines supplied respectively by Rhone-Poulenc and Witco. (*) HLAS is a linear alkylbenzene sulphonate in acid form and Na LAS is its sodium salt.

Sokalan CP5® is a polyacrylate polymer commercially available from BASF. All the compositions of the previous examples showed excellent benefits of immediate and long lasting gloss and the surfaces treated provided an excellent development of removal of limescale and were gentle on the user's skin when contacted. Also the redeposition of limescale deposits on a hard surface that was first treated with one of the compositions exemplified above was reduced, or even avoided, when said surface was brought back into contact with water, during a prolonged period, when they were used in their pure form or in their diluted form.

Claims (14)

1. NOVELTY OF THE INVENTION CLAIMS 1 .- A liquid acid composition suitable for removing stains containing limestones from a hard surface and having a pH of less than 5, characterized in that it comprises 0.01% to 20% of the total composition of a sulfamic acid, 0.01% a 45% by weight of the total composition of a second acid, and from 0.001% to 10% by weight of an acid stable polymer selected from the group consisting of a polycarboxylate polymer, a sulfonated polystyrene polymer, a homopolymer or copolymer of vinylpyrrolidone, a polyalkoxylene glycol, and mixtures thereof.
2. 2. The composition according to claim 1, further characterized in that said second acid is a weak or strong organic or inorganic acid or a mixture thereof, preferably a second acid having its first pKa not exceeding 5 or more. a mixture thereof, more preferably maleic acid, alkylsulfonic acid, arylsulfonic acid, citric acid, nitric acid, sulfuric acid, phosphoric acid, hydrochloric acid or a mixture thereof, and more preferably maleic acid.
3. 3. The composition according to any of the preceding claims, further characterized in that it comprises from 0.1% to 10% by weight of the total sulfamic acid composition, preferably from 0.1% to 5%.
4. 4. - The composition according to any of the preceding claims, further characterized in that it comprises from 0.1% to 25% by weight of a second acid or a mixture thereof, preferably from 1% to 20%, and more preferably from 1% to 18%
5. 5. The composition according to any of the preceding claims, further characterized in that said acid-stable polymer is a sulfonated homopolymer of (poly) styrene, or a sulphonated copolymer of styrene with an ethylenically unsaturated comonomer or a mixture thereof, preferably said polymers having a molecular weight of 5,000 to 10,000,000, and more preferably 50,000 to 1,000,000.
6. 6. The composition according to any of the preceding claims, further characterized in that said acid stable polymer is a polyacrylate polymer, preferably a copolymer of acrylic acid and maleic acid or a mixture thereof, more preferably a copolymer of acrylic acid and maleic acid having an average molecular weight in the acid form of 2,000 to 1,000,000, preferably 5,000 to 100,000, more preferably 10,000 to 80,000, and a ratio of acrylate segments: maleate segments in said copolymer from 30: 1 to 1: 1, more preferably from 10: 1 to 2: 1, or a mixture thereof.
7. 7. The composition according to any of the preceding claims, further characterized in that said acid stable polymer is a polyalkoxylene glycol according to the formula HO- (CH2-CHRO) nH, wherein R is hydrogen, or alkenyl group, group aryl or linear or branched alkyl group having from 1 to 30 carbon atoms, preferably from 1 to 16, more preferably from 1 to 8, and n is an integer from 5 to 1, 000, preferably from 10 to 100, or a mixture of them.
8. 8. The composition according to any of the preceding claims, further characterized in that said acid-stable polymer is a homopolymer of N-vinylpyrrolidone having the following repeating monomer: wherein n is an integer of 10 to 1,000,000, preferably 20 to 100,000 and more preferably 20 to 10,000, or a copolymer of N-vinylpyrrolidone and an alkylenically unsaturated monomer preferably selected from the group consisting of maleic acid, chloromaleic, fumaric acid, itaconic acid, citraconic acid, phenylmaleic acid, aconitic acid, acrylic acid, N-vinylimidazole, vinyl acetate, and anhydrides thereof, styrene, sulfonated styrene, alpha-methyl styrene, vinyltoluene, t-butyl styrene , and mixtures thereof.
9. 9. - The composition according to any of the preceding claims, further characterized in that it comprises

   0. 001% to 5% by weight of the total composition of a stable polymer in acid or mixtures thereof, preferably from 0.002% to 2%, more preferably from 0.01% to 1%.
10. 10. The composition according to any of the preceding claims, further characterized in that it comprises a surfactant or a mixture thereof at a level of 40% by weight of the total composition, typically selected from the group consisting of anionic surfactants, non-ionic, cationic, amphoteric, switterionic, and mixtures thereof, more preferably at least one zwitterionic surfactant according to the formula: R? -N + (R2) (R3) R4X ", where Ri is a chain of aliphatic or aromatic hydrocarbon, saturated or unsaturated, substituted or unsubstituted, which may contain linking groups such as amido groups, ester groups, preferably an alkyl group containing from 1 to 24 carbon atoms, more preferably from 8 to 18, or an amido radical of the formula Ra-C (O) -NRb- (C (Rc) 2) m, wherein Ra is an aliphatic or aromatic hydrocarbon chain, saturated or unsaturated, substituted or unsubstituted, containing and 8 to 20 carbon atoms, Rb is a hydrogen, a short chain alkyl or substituted alkyl containing from 1 to 4 carbon atoms, preferably a group selected from the group consisting of methyl, ethyl, propyl, ethyl substituted with hydroxy or propyl, and mixtures thereof, more preferably methyl or hydrogen, Rc is selected from the group consisting of hydrogen and hydroxy groups, and m is from 1 to 4, preferably from 2 to 3, more preferably 3, with no more of a hydroxy group in any portion (C (Rc) 2); 2 is hydrogen, C 1 -C 6 alkyl, hydroxyalkyl or other substituted C 1 -C 6 alkyl group; R3 is C6-C6alkyl, hydroxyalkyl or other alkyl group of CI-CT which can also be attached to R2 to form ring structures with N, or a C-pCß carboxylic acid group or a sulfonate group of CI -CT; R4 is a linking moiety of the cationic nitrogen atom to the hydrophilic group and is typically an alkylene, hydroxyalkylene, or polyalkoxy group containing from 1 to 10 carbon atoms; and X is the hydrophilic group that is a The carboxylate or sulfonate group, or a mixture thereof. 1.
11. The composition according to any of the preceding claims, further characterized in that said composition "A has a pH of less than 4, preferably a pH of 0.1 to 2.5, and more preferably 0.1 to 2. 15
12. 12. A process for treating a hard surface soiled by spots containing limestones, characterized in that a liquid composition acid according to any of the preceding claims, is applied in its pure form or in its diluted form on said surface, and then it is allowed to act on said surfaces, and 20 then it is removed by rinsing.
13. 13. The use of a liquid acid composition comprising at least one acid or a mixture thereof, and an acid-stable polymer selected from the group consisting of a polycarboxylate polymer, a sulfonated polystyrene polymer, a homopolymer or copolymer of vinylpyrrolidone, a polyalkoxylene glycol, and a mixture thereof, for removing spots containing limestones from a hard surface, whereby long-lasting gloss is provided to said surface after it has been first treated with said composition.
14. 14. The use of a liquid acid composition comprising at least one acid or a mixture thereof and an acid-stable polymer selected from the group consisting of a polycarboxylate polymer, a sulfonated polystyrene polymer, a homopolymer or copolymer of vinylpyrrolidone, a polyalkoxylene glycol, and a mixture thereof, suitable for removing spots containing limestones from a hard surface, to reduce the formation of limescale deposits on said hard surface when contacted with water, after said hard surface has been treated first with said composition.