Process for making granules comprising at least one chelating agent and / or at least one polymer

Abstract

The present invention deals with a process for making granules with increased bulk density comprising at least one chelating agent and / or at least one polymer.

Description

[0001]230235 1 Process for making granules comprising at least one chelating agent and / or at least one poly- mer Description The present invention deals with a process for making granules comprising at least one chelat- ing agent and / or at least one polymer. Chelating agents such as methyl glycine diacetic acid (MGDA) and their respective alkali metal salts are useful sequestrants for alkaline earth metal ions such as Ca2+and Mg2+. For that rea- son, they are recommended and used for various purposes such as laundry detergents and for automatic dishwashing (ADW) formulations, in particular for so-called phosphate-free laundry detergents and phosphate-free ADW formulations. For shipping such chelating agents, in most cases either solids such as powders or granules are being applied or aqueous solutions. Depending on the type of product – liquid home care and fabric care products versus solid home care and fabric care products – and the manufacturing process of solid home care and fabric care products care product manufacturers may either prefer to handle solutions of ami- nocarboxylates or solid aminocarboxylates, for example joint spray drying or solid mixing. Pow- ders and granules of aminocarboxylates may be shipped economically due to their high active ingredient content that goes along with low water content. Therefore, convenient processes for providing granules are still of great commercial interest. Commonly ADW formulations contain up to 40% of MGDA builder and are packaged in single unit doses, in brief also “SUD”. The space in these SUD is limited and thus a higher bulk density is desired, because a higher bulk density allows for more active product per volume unit in these SUDs. Furthermore, commonly granules containing chelating agents, like MGDA, and / or polymers contain a certain amount of so-called “fines”, which is undesired by manufacturers of ADW formulations. The fines may also pose risks to the environment and the health of employ- ees working with the MGDA and / or polymers containing the fines. The term “fines” in the context of the present invention refers to particles with a particle size (diameter) of less than 300 µm. WO 2023 / 105006 A1 discloses a granular additive for a detergent composition, wherein the granular additive comprises at least one builder and at least one cationic polymer. 230235 2 EP 0520582 B1 describes a process for producing a free-flowing spray-dried particulate deter- gent composition containing a zeolite and, optionally, citric acid. The document does not refer to the use of chelating agents like MGDA or IDS. WO 2021 / 115851 discloses a process for making a granule containing at least one chelating agent and optionally at least one polymer by spray granulation, following by an after-treatment step. However, the bulk density of the resulting granules leaves room for improvement. It was therefore an objective of the present invention to provide a process that yields granules of chelating agents and / or polymers with a high or increased bulk density and a reduced amount of fines. It was also an objective of the present invention to provide granules of chelating agents and / or polymers with a high or increased bulk density and a reduced amount of fines. Accordingly, the process described herein has been found, hereinafter also referred to as in- ventive process or as process according to the present invention. The present invention thus relates to a process for making granules with high bulk density, and preferably with lower amount of fines, containing (A) at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and iminodisuccinic acid (IDS) and / or at least one polymer (PA), and, optionally, (B) at least one homo- or copolymer, selected from the list consisting of polyaspartates with an average molecular weight Mwin the range of from 1,000 to 20,000 g / mole and homo- or copolymers of (meth)acrylic acid, partially or fully neutralized with alkali, said process comprising the steps of (a) providing an aqueous solution or slurry containing chelating agent (A) and / or poly- mer (PA) and, if applicable, (co)polymer (B), (b) removing most of said water by spray granulation in a fluidized bed, thereby obtain- ing a granule, (c) treating the resultant granule from step (b) with air or an inert gas in a vessel of which at least one part rotates around a horizontal or vertical axis and wherein said vessel is selected from high-speed mixers, paddle mixers, ploughshare mixers free- fall mixers, mixers with an additional chopper unit intensifying the mixing and mix- ers, wherein the vessel additionally contains an aqueous composition (AC) compris- ing at least one surfactant (S), wherein surfactant (S) preferably generates at least 230235 3 100 ml of foam when measured according to EN 14371:20004 (at 0.1 g / l, 25 °C, normal pressure and after 10 min in water), and wherein surfactant (S) is preferably selected from the list consisting of non-ionic surfactants (S1), anionic surfactants (S2), amphoteric surfactants (S3) and mixtures thereof . The feature in the present inventive process saying that the vessel “additionally contains an aqueous composition (AC) comprising at least one surfactant (S)” includes any potential pro- cess variant to that effect. In particular, it covers – without limitation – the alternatives wherein (i) the vessel is filled with both the granule resulting from step (b) and with aqueous composition (AC), and then the treatment starts, or (ii) the vessel is pre-filled with aqueous composition (AC) and then the gran- ule resulting from step (b) is introduced into the vessel and the treatment starts, or (iii) the ves- sel is pre-filled with the granule resulting from step (b), and then the aqueous composition (AC) is introduced gradually during the treatment, preferably through a foam generation nozzle. In a preferred embodiment, the vessel is pre-filled with the granule resulting from step (b), and subsequently aqueous composition (AC) is introduced gradually during the treatment, preferably through a foam generation nozzle. The foam generation nozzle generates foam by mixing two streams, e. g. air in one stream and liquid (containing surfactant) in another stream; this is de- picted schematically in figures 3 and 4 below. The aqueous composition (AC) preferably comprises between 0.01 and 10.00 % by weight of surfactant S, preferably 0.10 and 3.00 % by weight, more preferably 0.20 to 2 % by weight of surfactant S. The inventive process is a process for making a granule. The term “granule” in the context of the present invention refers to particulate materials that are solids at ambient temperature and that preferably have an average particle diameter (D50) in the range of from 0.1 mm to 2 mm, preferably 0.4 mm to 1.25 mm, even more preferably 400 µm to 1 mm. The average particle diameter of inventive granules can be determined, e.g., by optical or preferably by sieving methods. Sieves employed may have a mesh in the range of from 60 to 3,000 µm. In one embodiment of the present invention, granules made according to the present invention have a broad particle diameter distribution. In another embodiment of the present invention, granules made according to the present invention have a narrow particle diameter distribution. The particle diameter distribution can be adjusted, if desired, by multiple sieving steps. 230235 4 Granules made by the inventive process may contain residual moisture, moisture referring to water including water of crystallization and adsorbed water. The amount of water may be in the range of from 0.1 to 20% by weight, preferably 1 to 15% by weight, referring to the total solids content of the respective granule, and may be determined by Karl-Fischer-titration or by drying at 160 to 200°C to constant weight with infrared light. Particles of granules made by the inventive process have a regular shape; they have smooth surfaces, no sharp edges, reducing the generation of fines while moving. Particles of granules made by the inventive process contain at least one chelating agent and / or polymer (PA), hereinafter also referred to as chelating agent (A). Chelating agent (A) is selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and of iminodisuccinic acid (IDS). Alkali metal salts of MGDA are selected from compounds according to general formula (I a) [CH3-CH(COO)-N(CH2-COO)2]M3-xHx(I a) wherein M is selected from alkali metal cations, same or different, for example cations of lithium, sodium, potassium, rubidium, cesium, and combinations of at least two of the foregoing. Preferred ex- amples of alkali metal cations are sodium and potassium and combinations of sodium and po- tassium. x in formula (I a) is in the range of from zero to 1.0, preferred are zero to 0.5. In a particularly preferred embodiment, x is zero. Alkali metals salts IDS are selected from compounds according to general formula (I b) [H-N-(CH(COO)-CH2COO)2]M4-xHx (I c) wherein M is selected from alkali metal cations, same or different, as defined above, x in formula (I b) is in the range of from zero to 2.0, preferred are zero to 0.5. In a particularly preferred embodiment, x is zero. 230235 5 In one embodiment of the present invention, alkali metal salts of MGDA are selected from lithi- um salts, potassium salts and preferably sodium salts of MGDA. MGDA can be partially or pref- erably fully neutralized with the respective alkali. In a preferred embodiment, an average of from 2.7 to three COOH groups of MGDA is neutralized with alkali metal, preferably with sodium. In a particularly preferred embodiment, chelating agent (A) is the trisodium salt of MGDA. MGDA and its respective alkali metal salts are selected from the racemic mixtures, the D- isomers and the L-isomers, and from mixtures of the D- and L-isomers other than the racemic mixtures. Preferably, MGDA and its respective alkali metal salts are selected from the racemic mixture and from mixtures containing in the range of from 55 to 85 mole-% of the L-isomer, the balance being D-isomer. Particularly preferred are mixtures containing in the range of from 60 to 80 mole-% of the L-isomer, the balance being D-isomer. Other particularly preferred embodi- ments are racemic mixtures. IDS and its respective alkali metal salts are selected from various mixtures of stereoisomers, for example D,D-IDS, L,L-IDS and D,L-IDS and combinations therefrom. Preferred are optically inactive mixtures since they are cheaper to be manufactured. In any way, minor amounts of chelating agent (A) may bear a cation other than alkali metal. It is thus possible that minor amounts, such as 0.01 to 5 mol-% of total MGDA or IDS, respectively, bear alkali earth metal cations such as Mg2+or Ca2+, or an Fe2+or Fe3+cation. In one embodiment of the present invention, alkali metal salt of chelating agent (A) may contain one or more impurities that may result from the synthesis of the respective chelating agent (A). In the case of MGDA and its alkali metal salts, such impurities may be selected from propionic acid, lactic acid, alanine, nitrilotriacetic acid (NTA) or the like and their respective alkali metal salts. In the case of IDS, such impurities may be selected from maleic acid, monoamides of ma- leic / fumaric acid, and racemic asparagine. Such impurities are usually present in minor amounts. “Minor amounts” in this context refer to a total of 0.1 to 5% by weight, referring to alka- li metal salt of chelating agent (A), preferably up to 2.5% by weight. In the context of the present invention, such minor amounts are neglected when determining the composition of granule made according to the inventive process. In a special embodiment of the present invention, a combination alkali metal salts of at least two different chelating agents is used, for example sodium salts of MGDA and ISD in a weight ratio 230235 6 of from 1:1 to 5:1. In other embodiments, alkali metal salts of only one chelating agent is used, in particular sodium metal salts of MGDA. Particles of granules made by the inventive process may further contain polymer (PA) and, op- tionally, (B) at least one homo- or copolymer (PB) of (meth)acrylic acid, partially or fully neutralized with alkali, hereinafter also referred to as “polymer (B)”. Polymers (B) that are homopoly- mers are also being referred to as “homopolymers (B)”, and polymers (B) that are copol- ymers are also being referred to as “copolymers (B)”. Polymer (PA) and / or (PB) may also be selected from polyaspartates with an average molecular weight Mwin the range of from 1,000 to 20,000 g / mole. Polymer (PA) and / or (PB) may also be selected from graft copolymers comprising at least one graft base selected from nonionic mono-, di-, oligo- and polysaccharides and polymers P ob- tainable by grafting ethylenically unsaturated monomers M onto the graft base, wherein the monomers M comprise at least one monomer b1 selected from monoethylenically unsaturated mono- and dicarboxylic acids; and ) at least one monomer b2 selected from ethylenically un- saturated monomers having a permanent cationic charge. Polyaspartic acid is well known as biodegradable dispersing and scale inhibiting polymer. Three main methods have been developed for the industrial production of polyaspartic acid and its sodium salts: (1) Thermal polycondensation of aspartic acid followed by alkaline hydrolysis of the interme- diate polysuccinimide; (2) Thermal polycondensation of aspartic acid in the presence of an acid catalyst such as phosphoric acid, sulfuric acid or methanesulfonic acid followed by alkaline hydrolysis of the intermediate polysuccinimide; (3) Polymerization of maleic acid anhydride in the presence of ammonia or ammonium salts followed by alkaline hydrolysis of the intermediate polysuccinimide. Regardless of the synthesis route, the intermediate polysuccinimide has to be hydrolyzed by means of e.g. sodium hydroxide in order to obtain an aqueous polyaspartate solution. Acidifica- tion of the polyaspartate solution with mineral acids such as hydrochlorid or sulfur acid gives the polyaspartic acid. 230235 7 Modified polyaspartic acid which can be used according to the present invention is preparable by polycondensation of (i) 50 to 99 mol%, preferably 60 to 95 mol%, particularly preferably 80 to 95 mol%, of aspar- tic acid; and (ii) 1 to 50 mol%, preferably 5 to 40 mol%, particularly preferably 5 to 20 mol%, of at least one carboxyl-containing compound, and subsequent hydrolysis of the co-condensates with the addition of a base, for example so- dium hydroxide solution, wherein (ii) is not an aspartic acid. The carboxyl-containing compound (ii) used in connection with the preparation of the polyaspar- tic acid to be used according to the invention can be, inter alia, a carboxylic acid (monocarbox- ylic acid or polycarboxylic acid), a hydroxycarboxylic acid and / or an amino acid (apart from as- partic acid). Such carboxylic acids or hydroxycarboxylic acids are preferably polybasic. In this connection, polybasic carboxylic acids can thus be used in the preparation of the polyaspartic acid to be used according to the invention, e.g. oxalic acid, adipic acid, fumaric acid, maleic acid, itaconic acid, aconitic acid, succinic acid, malonic acid, suberic acid, azelaic acid, diglyco- lic acid, glutaric acid, C1-C26 alkylsuccinic acids (e.g. octylsuccinic acid), C2-C26 alkenylsuccinic acids (e.g. octenylsuccinic acid), 1,2,3-propanetricarboxylic acid, 1,1,3,3-propanetetracarboxylic acid, 1,1,2,2-ethanetetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,2,3-propane- tetracarboxylic acid, or 1,3,3,5-pentanetetracarboxylic acid. Furthermore, in this connection it is also possible to use polybasic hydroxycarboxylic acids, e.g. citric acid, isocitric acid, mucic acid, tartaric acid, tartronic acid, or malic acid. Amino acids that can be used in this connection are, inter alia, aminocarboxylic acids (e.g. glutamic acid, cysteine), basic diaminocarboxylic acids (e.g. lysine, arginine, histidine, aminocaprolactam), neutral amino acids (e.g. glycine, alanine, valine, leucine, isoleucine, methionine, cysteine, norleucine, caprolactam, asparagine, iso- asparagine, glutamine, isoglutamine), aminosulfonic acids (e.g. taurine), hydroxylamino acids (e.g. hydroxyproline, serine, threonine), iminocarboxylic acids (e.g. proline, iminodiacetic acid), or aromatic and heterocyclic amino acids (e.g. anthranilic acid, tryptophan, tyrosine, histidine), but not aspartic acid. Preferred carboxyl-containing compounds (ii) in connection with the prepa- ration of the modified polyaspartic acids to be used according to the invention are 1,2,3,4- butanetetracarboxylic acid, citric acid, glycine, glutamic acid, itaconic acid, succinic acid, tau- rine, maleic acid and glutaric acid, particularly preferably 1,2,3,4-butanetetracarboxylic acid, citric acid, glycine and glutamic acid. 230235 8 The molecular weight (Mw) of the (modified) polyaspartic acid can easily be tuned by varying the reaction conditions. Molecular weights between 1000 g / mol and 100000 g / mol can be achieved by simple adjustion of the process parameters (temperature, catalyst, reaction time). The preferred molecular weight of the (modified) polyaspartic acid used according to the pre- sent invention lies in the range between 1000 g / mol and 20000 g / mol, preferably between 1500 and 15000 g / mol and particularly preferably between 2000 and 10000 g / mol. The aspartic acid (i) used in connection with the preparation of the (modified) polyaspartic acid to be used according to the invention can either be L- or D- and DL-aspartic acid. Preference is given to using L-aspartic acid. Polymer (PA) and / or (PB) may be selected from homopolymers of (meth)acrylic acid and of co- polymers (B) of (meth)acrylic acid, preferably of acrylic acid, partially or fully neutralized with alkali. In the context of the present invention, copolymers are those in which at least 50 mol-% of the comonomers are (meth)acrylic acid, preferably at least 75 mol-%, even more preferably 80 to 99 mol-%. Suitable comonomers for copolymers (PA) and / or (PB) are ethylenically unsaturated com- pounds, such as styrene, isobutene, ethylene, α-olefins such as propylene, 1-butylene, 1- hexene, and ethylenically unsaturated dicarboxylic acids and their alkali metal salty and anhy- drides such as but not limited to maleic acid, fumaric acid, itaconic acid disodium maleate, diso- dium fumarate, itaconic anhydride, and especially maleic anhydride. Further examples of suita- ble comonomers are C1-C4-alkyl esters of (meth)acrylic acid, for example methyl acrylate, me- thyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate. In one embodiment of the present invention, (co)polymer (PA) and / or (PB)is selected from co- polymers of (meth)acrylic acid and a comonomer bearing at least one sulfonic acid group per molecule. Comonomers bearing at least one sulfonic acid group per molecule may be incorpo- rated into (co)polymer (B) as free acid or least partially neutralized with alkali. Particularly pre- ferred sulfonic-acid-group-containing comonomers are 1-acrylamido-1-propanesulfonic acid, 2- acrylamido-2-propanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2- methacrylamido-2-methylpropanesulfonic acid, 3-methacrylamido-2-hydroxypropanesulfonic acid, allylsulfonic acid, methallylsulfonic acid, allyloxybenzenesulfonic acid, methallyloxyben- zenesulfonic acid, 2-hydroxy-3-(2-propenyloxy)propanesulfonic acid, 2-methyl-2-propene-1- sulfonic acid, styrenesulfonic acid, vinylsulfonic acid, 3-sulfopropyl acrylate, 2-sulfoethyl meth- 230235 9 acrylate, 3-sulfopropyl methacrylate, sulfomethacrylamide, sulfomethylmethacrylamide, and salts of said acids, such as the sodium salts, potassium salts or ammonium salts thereof. Copolymers (PA) and / or (PB) may be selected from random copolymers, alternating copoly- mers, block copolymers and graft copolymers, alternating copolymers and especially random copolymers being preferred. Useful copolymers (PA) and / or (PB) are, for example, random copolymers of acrylic acid and methacrylic acid, random copolymers of acrylic acid and maleic anhydride, ternary random co- polymers of acrylic acid, methacrylic acid and maleic anhydride, random or block copolymers of acrylic acid and styrene, random copolymers of acrylic acid and methyl acrylate. More preferred are homopolymers of methacrylic acid. Even more preferred are homopolymers of acrylic acid. (Co)polymer (PA) and / or (PB) may constitute straight-chain or branched molecules. Branching in this context will be when at least one repeating unit of such (co)polymer (B) is not part of the main chain but forms a branch or part of a branch. Preferably, (co)polymer (B) is not cross- linked. In one embodiment of the present invention, (co)polymer (PA) and / or (PB) has an average mo- lecular weight Mw in the range of from 1,200 to 30,000 g / mol, preferably from 2,500 to 20,000 g / mol and even more preferably from 5,000 to 18,500 g / mol, determined by gel permeation chromatography (GPC) and referring to the respective free acid. In one embodiment of the present invention, (co)polymer (PA) and / or (PB) is at least partially neutralized with alkali, for example with lithium or potassium or sodium or combinations of at least two of the forgoing, especially with sodium. For example, in the range of from 10 to 100 mol-% of the carboxyl groups of (co)polymer (B) may be neutralized with alkali, especially with sodium. In one embodiment of the present invention, (co)polymer (PA) and / or (PB) is selected from per- sodium salts of polyacrylic acid, thus, polyacrylic acid, fully neutralized with sodium. In one embodiment of the present invention, (co)polymer (PA) and / or (PB) is selected from a combination of at least one polyacrylic acid and at least one copolymer of (meth)acrylic acid and a comonomer bearing at least one sulfonic acid group per molecule, both polymers being fully neutralized with alkali. 230235 10 In one embodiment of the present invention, (co)polymer (PA) and / or (PB) is selected from per- sodium salts of polyacrylic acid with an average molecular weight Mwin the range of from 1,200 to 30,000 g / mol, preferably from 2,500 to 20,000 g / mol and even more preferably from 5,000 to 18,500 g / mol, determined by gel permeation chromatography (GPC) and referring to the re- spective free acid. In embodiments wherein a (co)polymer (PA) and / or (PB) is present, the weight ratio of (A):(B) is in the range of from 2 : 1 up to 1,000 to 1, preferably 7.5 : 1 up to 1,000:1, and more preferably 40:1 to 100:1. In this weight ratio, impurities of chelating agent (A) that stem from the synthesis, see above, are neglected. Surfactants In general, the surfactants (S) which may be used in the inventive process are selected from foam-generating surfactants, i. e. surfactants which form sustainable foam in the presence of water. In particular, surfactant (S) preferably generates at least 100 ml of foam, more preferably at least 200 ml of foam, even more preferably at least 300 ml of foam, when measured according to EN 14371:2004 at 0.1 g / l, 25 °C, normal pressure and after 10 min circulation in demineral- ized water. Surfactant (S) in aqueous composition (AC) is preferably selected from the list consisting of non-ionic surfactants (S1), anionic surfactants (S2), amphoteric surfactants (S3) and mixtures thereof. In one embodiment of the present invention, the non-ionic surfactant (S1) may be selected from alkylpolyglycosides (APGs) and / or alkoxylates (and mixtures thereof). In one embodiment of the present invention, the non-ionic surfactant (S1) may be selected from ethoxylates based on 2-propylheptanol, ethoxylated with 5 to 20 ethylene oxide units. In another embodiment of the present invention, the anionic surfactant (S2) may be selected from sodium laurylsulfate (SLS) or sodium laureth sulfate with 1 – 5 EO units (or mixtures thereof). In one embodiment of the present invention, the amphoteric surfactant (S3) is selected from. compounds of general formulae (AMS2a), (AMS2b), or (AMS2c), which may be called betaines and / or sulfobetaines (AMS2): 230235 11 The variables in general formulae (AMS2a), (AMS2b) and (AMS2c) are defined as follows: R11is selected from linear (straight-chain; n-) or branched C7-C22alkyl and linear (straight-chain; n-) or branched C7-C22alkenyl. R12are each independently selected from linear (straight-chain; n-) C1-C4 alkyl. R13is selected from C1-C5 alkyl and hydroxy C1-C5 alkyl; for example 2-hydroxypropyl. A- is selected from carboxylate and sulfonate. The integer r in general formulae (AMS2a), (AMS2b), and (AMS2c) is in the range of 2 to 6. Preferably, amphoteric surfactant (S3) is selected from acylamidopropylbetaines, more preferably cocamidopropylbetaine. In a preferred embodiment of the inventive process, surfactant (S) is selected from the list con- sisting of C8 to C10 alkylpolyglucoside with a degree of polymerization of 1.2 – 1.8, C8 to C14 alkylpolyglucoside with a degree of polymerization of 1.2 – 1.8, C16 to C18 ethoxylate with 25 EO units, ethoxylate of 2-propylheptanol and C16 to C18 alcohol with 7 EO units, ethoxylate of 2-propylheptanol with 7 EO units, sulfated C12 to C14 ethoxylate with 2 EO units, cocami- dopropylbetaine, and mixtures thereof. 230235 12 In one embodiment, the aqueous composition (AC) comprises at least one non-ionic surfactant (S1) and at least one anionic surfactant (S2). In one embodiment, the aqueous composition (AC) comprises at least one non-ionic surfactant (S1) and at least one amphoteric surfactant (S3).In a further embodiment, the aqueous compo- sition (AC) comprises at least one anionic surfactant (S2) and at least one amphoteric surfac- tant (S3). In another embodiment, the aqueous composition (AC) comprises at least one non-ionic surfac- tant (S1), at least one anionic surfactant (S2) and at least one amphoteric surfactant (S3). In one embodiment, the aqueous composition (AC) comprises at least one non-ionic surfactant (S1) and at least one anionic surfactant (S2) in a molar ratio of 10:1 to 1:10. In one embodiment, the aqueous composition comprises at least one non-ionic surfactant (S1) and at least one amphoteric surfactant (S3) in a molar ratio of 10:1 to 1:10. In a further embodiment, the aqueous composition (AC) comprises at least one anionic surfac- tant (S2) and at least one amphoteric surfactant (S3) in a molar ratio of 10:1 to 1:10. The inventive process is now described in more detail. In step (a), an aqueous solution or aqueous slurry of chelating agent (A) and / or polymer (PA) and, if applicable, (co)polymer (PB), is provided. Such aqueous solution or slurry can be manu- factured be processes known per se. For example, an aqueous solution of alkali metal salts of chelating agent (A) may be obtained from their synthesis. Such solution may be further concen- trated by addition of solid chelating agent (A) or by evaporation of water. (Co)polymer (PA) and / or (PB) may be added, if desired, as solid or as aqueous solution. Step (a) can be performed at ambient temperature. In other embodiments, step (a) is being per- formed at 20° C or at elevated temperature, for example at a temperature in the range of from 25 to 90°C, preferably 60 to 75°C. The water used in step (a) may be present in an amount that both chelating agent (A) and (co)polymer (PA) and / or (PB) are dissolved. However, it is also possible to use less amounts of water and mix chelating agent (A) and (co)polymer (PA) and / or (PB) in a way that a slurry is being formed. Solutions are preferred. 230235 13 In one embodiment of the present invention, the total solids content of such solution or slurry formed as result of step (a) is in the range of from 20 to 75%, preferably 35 to 50%. In step (b), most of the water is removed from the aqueous solution or slurry provided in step (a) by spray granulation in a fluidized bed. The aqueous slurry or aqueous solution according to step (a) may have a temperature in the range of from 15 to 95°C, preferably 20 to 90°C and even more preferably 50 to 90°C. In step (b), said aqueous slurry or aqueous solution is introduced into a spray granulator. In the context of the present invention, a spray granulator usually contains a fluidized bed, in the con- text of the present invention it is a fluidized bed of chelating agent (A), or of granule made ac- cording to the present invention. Such fluidized bed of chelating agent (A) is preferably in the form of chelating agent in crystalline form, for example at least 66% crystalline form, determined by X-Ray diffraction. In one embodiment of the present invention, the fluidized bed may have a temperature in the range of from 75 to 150°C, preferably 80 to 110°C. Spraying is being performed through one or more nozzles per spray granulator. Suitable noz- zles are, for example, high-pressure rotary drum atomizers, rotary atomizers, three-fluid noz- zles, single-fluid nozzles, three-fluid nozzles and two-fluid nozzles, single-fluid nozzles and two- fluid nozzles and three-fluid nozzles being preferred. The first fluid is the aqueous slurry or aqueous solution or emulsion, respectively, the second fluid is compressed hot gas, also re- ferred to as hot gas inlet stream, for example with a pressure of 1.1 to 7 bar. The hot gas inlet stream may have a temperature in the range of from at least 125°C to 250°C, preferably 150 to 250°C, even more preferably 160 to 220°C. In step (b), the aqueous slurry or aqueous solution of complexing agent (A) and / or polymer (PA), and, optionally, (co)polymer (B) is introduced in the form of droplets into said fluidized bed. In one embodiment of the present invention, the droplets formed during the spray- granulating have an average diameter in the range of from 10 to 500 µm, preferably from 20 to 180 µm, even more preferably from 30 to 100 µm. In one embodiment of the present invention, the off-gas departing the spray granulator may have a temperature in the range of from 40 to 140°C, preferably 80 to 110°C but in any way colder than the hot gas stream. Preferably, the temperature of the off-gas departing the drying vessel and the temperature of the solid product present in the drying vessel are identical. 230235 14 In one embodiment of the present invention, the pressure in the spray tower or spray granulator in step (b) is normal pressure ± 100 mbar, preferably normal pressure ± 20 mbar, for example one mbar less than normal pressure. In one embodiment of the present invention, especially in a process for making an inventive granule, the average residence time of chelating agent (A) in step (b) is in the range of from 2 minutes to 4 hours, preferably from 30 minutes to 2 hours. In embodiments wherein an aged slurry is used, such aging may take in the range of from 2 hours to 24 hours at the temperature preferably higher than ambient temperature. In the course of step (b), most of the water is removed in a fluidized bed. Most of the water shall mean that a residual moisture content of 0.1 to 20% by weight may remain, referring to the granule. In embodiments that start off from a solution, about 51 to 75% by weight of the water present in the aqueous solution is removed in step (b). A granule is obtained, hereinafter also referred to as “resultant particulate residue” or “granule from step (b)”. Said granule from step (b) has the appearance of a granule that may have a bulk density in the range of from 700 to 950 g / l, preferably more than 750 g / l . Particles of granule from step (b) may show some degree of irregularity in shape. At the end of step (b), the granule from step (b) is removed from the spray granulator. Said granule has been at least partially formed in the course of step (b) of the inventive process. Said removal may be performed through one or more openings in the spray tower or spray granula- tor. Preferably, such one or more openings are at the bottom of the respective spray tower or spray granulator. Granules are removed including fines and lumps. In step (c), the granule from step (b) is treated with air or an inert gas or a combination of the foregoing in a vessel of which at least one part rotates around a horizontal axis. Examples of inert gasses are nitrogen and rare gasses such as, but not limited to argon. Mixtures of air and inert gasses are feasible as well. Preferably, such air or inert gas is “dry”. In this context, dry is meant to understand less than 5 g H2O per kg of gas. As mentioned before, step (c) is carried out in a vessel of which at least one part rotates around a horizontal axis, for example a mixing element or a mixer. Preferably, the mixing element ro- tates around a horizontal axis while the rest of the reactor does not. 230235 15 Various embodiments of reactor design are possible to perform step (c) of the inventive pro- cess. Step (c) of the inventive process may be carried out in a compulsory mixer. Examples of compulsory mixers are paddle mixers and ploughshare mixers. Preferred mixers for process step (c) may be selected from the list consisting of paddle mixers, ploughshare mixers and intensive mixers (e. g. from company Eirich). It is also possible to perform step (c) in a so-called free-fall mixer. While free fall mixers utilize the gravitational forces for moving the particles compulsory mixers work with moving mixing elements and, in particular, with rotating mixing elements that are in- stalled in the mixing room. In the context of the present invention, the mixing room is the reactor interior. Examples of compulsory mixers are ploughshare mixers, paddle mixers and shovel mixers. Preferred are ploughshare mixers. Preferred ploughshare mixers are installed horizon- tally, the term horizontal referring to the axis around which the mixing element rotates. Prefera- bly, the inventive process is carried out in a shovel mixing tool, in a paddle mixing tool, in a blade mixing tool and, more preferably, in a ploughshare mixer, for example in accordance with the hurling and whirling principle. In one embodiment of the present invention, the inventive process is carried out in a free fall mixer. Free fall mixers are using the gravitational force to achieve mixing. In a preferred embod- iment, step (c) of the inventive process is carried out in a drum or pipe-shaped vessel that ro- tates around its horizontal axis. In a more preferred embodiment, step (c) of the inventive pro- cess is carried out in a rotating vessel that has baffles. In one embodiment of the present invention the vessel or at least parts of it rotates with a speed in the range of from 5 to 200 rounds per minute, preferred are 5 to 60 rounds per minute. In one embodiment of the present invention, step (c) of the inventive process is performed with compulsory mixer operating with a Froude Number (“Fr”) in the range of from 1 to 10. In another embodiment, step (c) of the inventive process is performed with a free-fall mixer operated at a Froude Number below 1. In the context of the present invention, the Froude Number is defined as Fr = v² / g·l, with the variable v as circumferential speed, the variable l being the diameter of, e.g., of the respective compulsory mixer or free-fall mixer, and the variable g being the gravita- tional acceleration. 230235 16 In a preferred version of the present invention, which allows for the pneumatic conveying of said particulate material, a pressure difference in the range of from up to 400 mbar is applied. Gran- ule may be blown out of the mixer or removed by suction. In one embodiment of the present invention, the inlet pressure is higher but close to the desired reactor pressure. Pressure drops of gas inlet have to be compensated. In one embodiment of the present invention, step (c) is carried out at a temperature in the range of from ambient temperature to 115°C, preferably 30 to 80°C. Preferably, the material obtained from step (b) is introduced directly into step (c) and cools down during step (c). In one embodiment of the present invention, step (c) has a duration in the range of from 1 mi- nute to 5 hours, preferably 5 to 30 minutes. During step (c), the gas atmosphere may be renewed, for example once up to 5 times per hour. After step (c), a granule with excellent spherical shape of the particles is obtained. It shows re- duced hygroscopicity and can be used directly for manufacture of, e.g., automatic dishwashing formulations. One object of the present invention is also a granule containing at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and iminodisuccinic acid (IDS) and / or polymer (PA), and, optionally, at least one homo- or copolymer of (meth)acrylic acid (PB) with a comonomer bearing at least one sulfonic acid group per molecule, partially or fully neutralized with alkali, and / or, optionally, polyaspartates with an average molecular weight Mwin the range of from 1,000 to 20,000 g / mole, in a weight ratio of (A):(B) of from 2 : 1 up to 1,000 : 1, wherein said granule contains at least 75% by weight of chelating agent (A) and / or polymer (PA), and wherein said granule has an average broadness to length ratio in the range of from 1:1 to 1:0.75. 230235 17 Anonther object of the present invention is furthermore the use of an inventive granule, or of a granule obtained (or obtainable) by the inventive process, for the manufacture of a cleaning agent, preferably for fibers or hard surfaces, wherein said cleaning agent optionally contains at least one peroxy compound selected from percarbonates, persulfates and perborates. The cleaning agent may be a dishwashing cleaning agent, in particular a cleaning agent for au- tomatic dishwashing applications. Applications Another aspect of the present invention is therefore the use of an inventive granule for the man- ufacture of a cleaning agent that may contain at least one bleaching agent, and in particular for the manufacture of cleaning agent for fibers or hard surfaces, wherein said cleaning agent con- tains at least one peroxy compound. Another aspect of the present invention is a process for making at a cleaning agent by combining at least one inventive granule with at least one bleach- ing agent, preferably at least one peroxy compound. Another aspect of the present invention is a cleaning agent, hereinafter also being referred to as inventive cleaning agent. Inventive cleaning agents may contain at least one bleaching agent and at least one inventive granule. Inventive cleaning agents show a reduced tendency for yellowing and therefore have an extended shelve-life. Examples of suitable peroxy compounds are sodium perborate, anhydrous or for example as monohydrate or as tetrahydrate or so-called dihydrate, sodium percarbonate, anhydrous or, for example, as monohydrate, hydrogen peroxide, persulfates, organic peracids such as peroxylau- ric acid, peroxystearic acid, peroxy-α-naphthoic acid, 1,12-diperoxydodecanedioic acid, per- benzoic acid, peroxylauric acid, 1,9-diperoxyazelaic acid, diperoxyisophthalic acid, in each case as free acid or as alkali metal salt, in particular as sodium salt, also sulfonylperoxy acids and cationic peroxy acids. In a preferred embodiment, peroxy compound is selected from inorganic percarbonates, persul- fates and perborates. Examples of sodium percarbonates are 2 Na2CO3·3 H2O2. Examples of sodium perborate are (Na2[B(OH)2(O2)]2), sometimes written as NaBO2·O2·3H2O instead. Most preferred peroxy compound is sodium percarbonate. The term “cleaning agents” includes compositions for dishwashing, especially hand dishwash and automatic dishwashing and ware-washing, and compositions for hard surface cleaning such as, but not limited to compositions for bathroom cleaning, kitchen cleaning, floor cleaning, de- 230235 18 scaling of pipes, window cleaning, car cleaning including truck cleaning, furthermore, open plant cleaning, cleaning-in-place, metal cleaning, disinfectant cleaning, farm cleaning, high pressure cleaning, and in addition, laundry detergent compositions. Such cleaning agents may be liquids, gels or preferably solids at ambient temperature, solids cleaning agents being preferred. They may be in the form of a powder or granule or in the form of a unit dose, for example as a tablet. In one embodiment of the present invention, inventive cleaning agents may contain in the range of from 2 to 50 % by weight of inventive granule, in the range of from 0.5 to 15 % by weight of bleach. Percentages are based on the solids content of the respective inventive cleaning agent. Inventive cleaning agents may contain further ingredients such as one or more surfactants that may be selected from non-ionic, zwitterionic, cationic, and anionic surfactants. Other ingredients that may be contained in inventive cleaning agents may be selected from bleach activators, bleach catalysts, corrosion inhibitors, sequestering agents other than chelating agent (A), en- zymes, fragrances, dyestuffs, antifoams, and builders. Particularly advantageous inventive cleaning agents may contain one or more complexing agents other than MGDA or GLDA. Advantageous detergent compositions for cleaners and ad- vantageous laundry detergent compositions may contain one or more sequestrant (chelating agent) other than a mixture according to the present invention. Examples for sequestrants other than a mixture according to the present invention are citrate, phosphonic acid derivatives, for example the disodium salt of hydroxyethane-1,1-diphosphonic acid (“HEDP”), and polymers with complexing groups like, for example, polyethylenimine in which 20 to 90 mole-% of the N- atoms bear at least one CH2COO- group, and their respective alkali metal salts, especially their sodium salts, for example IDS-Na4, and trisodium citrate, and phosphates such as STPP (sodi- um tripolyphosphate). Due to the fact that phosphates raise environmental concerns, it is pre- ferred that advantageous inventive cleaning agents are free from phosphate. "Free from phos- phate" should be understood in the context of the present invention, as meaning that the con- tent of phosphate and polyphosphate is in sum in the range from 10 ppm to 0.2% by weight, determined by gravimetric methods and referring to the respective inventive cleaning agent. Inventive cleaning agents may contain one or more surfactant, preferably one or more non-ionic surfactant. 230235 19 Preferred non-ionic surfactants are alkoxylated alcohols, di- and multiblock copolymers of eth- ylene oxide and propylene oxide and reaction products of sorbitan with ethylene oxide or pro- pylene oxide, alkyl polyglycosides (APG), hydroxyalkyl mixed ethers and amine oxides. Preferred examples of alkoxylated alcohols and alkoxylated fatty alcohols are, for example, compounds of the general formula (I) in which the variables are defined as follows: R1is identical or different and selected from hydrogen and linear C1-C10-alkyl, preferably in each case identical and ethyl and particularly preferably hydrogen or methyl, R2is selected from C8-C22-alkyl, branched or linear, for example n-C8H17, n-C10H21, n-C12H25, n-C14H29, n-C16H33 or n-C18H37, R3is selected from C1-C10-alkyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl or isodecyl, m and n are in the range from zero to 300, where the sum of n and m is at least one, preferably in the range of from 3 to 50. Preferably, m is in the range from 1 to 100 and n is in the range from 0 to 30. In one embodiment, compounds of the general formula (I) may be block copolymers or random copolymers, preference being given to block copolymers. Other preferred examples of alkoxylated alcohols are, for example, compounds of the general formula (II) 230235 20 in which the variables are defined as follows: R1is identical or different and selected from hydrogen and linear C1-C0-alkyl, preferably iden- tical in each case and ethyl and particularly preferably hydrogen or methyl, R4is selected from C6-C20-alkyl, branched or linear, in particular n-C8H17, n-C10H21, n-C12H25, n-C14H29, n-C16H33, n-C18H37, a is a number in the range from zero to 10, preferably from 1 to 6, b is a number in the range from 1 to 80, preferably from 4 to 20, d is a number in the range from zero to 50, preferably 4 to 25. The sum a + b + d is preferably in the range of from 5 to 100, even more preferably in the range of from 9 to 50. Preferred examples for hydroxyalkyl mixed ethers are compounds of the general formula (III) in which the variables are defined as follows: R1is identical or different and selected from hydrogen and linear C1-C10-alkyl, preferably in each case identical and ethyl and particularly preferably hydrogen or methyl, R2is selected from C8-C22-alkyl, branched or linear, for example iso-C11H23, iso-C13H27, n- C8H17, n-C10H21, n-C12H25, n-C14H29, n-C16H33 or n-C18H37, R3is selected from C1-C18-alkyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, isodecyl, n-dodecyl, n-tetradecyl, n-hexadecyl, and n-octadecyl. 230235 21 The variables m and n are in the range from zero to 300, where the sum of n and m is at least one, preferably in the range of from 5 to 50. Preferably, m is in the range from 1 to 100 and n is in the range from 0 to 30. Compounds of the general formula (II) and (III) may be block copolymers or random copoly- mers, preference being given to block copolymers. Further suitable nonionic surfactants are selected from di- and multiblock copolymers, com- posed of ethylene oxide and propylene oxide. Further suitable nonionic surfactants are selected from ethoxylated or propoxylated sorbitan esters. Amine oxides or alkyl polyglycosides, espe- cially linear C4-C16-alkyl polyglucosides and branched C8-C14-alkyl polyglycosides such as com- pounds of general average formula (IV) are likewise suitable. wherein the variables are defined as follows: R5is C1-C4-alkyl, in particular ethyl, n-propyl or isopropyl, R6is -(CH2)2-R5, G1is selected from monosaccharides with 4 to 6 carbon atoms, especially from glucose and xylose, x in the range of from 1.1 to 4, x being an average number. An overview of suitable further nonionic surfactants can be found in EP-A 0851023 and in DE- A 19819187. Mixtures of two or more different nonionic surfactants may also be present. Other surfactants that may be present are selected from amphoteric (zwitterionic) surfactants and anionic surfactants and mixtures thereof. 230235 22 Examples of amphoteric surfactants are those that bear a positive and a negative charge in the same molecule under use conditions. Preferred examples of amphoteric surfactants are so- called betaine-surfactants. Many examples of betaine-surfactants bear one quaternized nitrogen atom and one carboxylic acid group per molecule. A particularly preferred example of amphoter- ic surfactants is cocamidopropyl betaine (lauramidopropyl betaine). Examples of amine oxide surfactants are compounds of the general formula (V) R7R8R9N→O (V) wherein R7, R8and R9are selected independently from each other from aliphatic, cycloaliphatic or C2-C4-alkylene C10-C20-alkylamido moieties. Preferably, R7is selected from C8-C20-alkyl or C2- C4-alkylene C10-C20-alkylamido and R8and R9are both methyl. A particularly preferred example is lauryl dimethyl aminoxide, sometimes also called lauramine oxide. A further particularly preferred example is cocamidylpropyl dimethylaminoxide, some- times also called cocamidopropylamine oxide. Examples of suitable anionic surfactants are alkali metal and ammonium salts of C8-C18-alkyl sulfates, of C8-C18-fatty alcohol polyether sulfates, of sulfuric acid half-esters of ethoxylated C4- C12-alkylphenols (ethoxylation: 1 to 50 mol of ethylene oxide / mol), C12-C18 sulfo fatty acid alkyl esters, for example of C12-C18 sulfo fatty acid methyl esters, furthermore of C12-C18-alkylsulfonic acids and of C10-C18-alkylarylsulfonic acids. Preference is given to the alkali metal salts of the aforementioned compounds, particularly preferably the sodium salts. Further examples for suitable anionic surfactants are soaps, for example the sodium or potassi- um salts of stearoic acid, oleic acid, palmitic acid, ether carboxylates, and alkylether phos- phates. In one embodiment of the present invention, inventive cleaning agents that are determined to be used as laundry detergent compositions may contain 0.1 to 60 % by weight of at least one sur- factant, selected from anionic surfactants, amphoteric surfactants and amine oxide surfactants. In one embodiment of the present invention, inventive cleaning agents that are determined to be used for hard surface cleaning may contain 0.1 to 60 % by weight of at least one surfactant, selected from anionic surfactants, amphoteric surfactants and amine oxide surfactants. Inventive cleaning agents may comprise one or more bleach catalysts. Bleach catalysts can be selected from bleach-boosting transition metal salts or transition metal complexes such as, for example, manganese-, iron-, cobalt-, ruthenium- or molybdenum-salen complexes or carbonyl complexes. Manganese, iron, cobalt, ruthenium, molybdenum, titanium, vanadium and copper complexes with nitrogen-containing tripod ligands and also cobalt-, iron-, copper- and rutheni- um-amine complexes can also be used as bleach catalysts. Inventive cleaning agents may comprise one or more bleach activators, for example N- methylmorpholinium-acetonitrile salts (“MMA salts”), trimethylammonium acetonitrile salts, N- acylimides such as, for example, N-nonanoylsuccinimide, 1,5-diacetyl-2,2-dioxohexahydro- 1,3,5-triazine (“DADHT”) or nitrile quats (trimethylammonium acetonitrile salts). Further examples of suitable bleach activators are tetraacetylethylenediamine (TAED) and tetraacetylhexylenediamine. Inventive cleaning agents may comprise one or more corrosion inhibitors. In the present case, this is to be understood as including those compounds which inhibit the corrosion of metal. Ex- amples of suitable corrosion inhibitors are triazoles, in particular benzotriazoles, bisbenzotria- zoles, aminotriazoles, alkylaminotriazoles, also phenol derivatives such as, for example, hydro- quinone, pyrocatechol, hydroxyhydroquinone, gallic acid, phloroglucinol or pyrogallol. In one embodiment of the present invention, inventive cleaning agents comprise in total in the range from 0.1 to 1.5% by weight of corrosion inhibitor. Inventive cleaning agents may comprise one or more builders, selected from organic and inor- ganic builders. Examples of suitable inorganic builders are sodium sulfate or sodium carbonate or silicates, in particular sodium disilicate and sodium metasilicate, zeolites, sheet silicates, in particular those of the formula α-Na2Si2O5, β-Na2Si2O5, and δ-Na2Si2O5, also fatty acid sul- fonates, α-hydroxypropionic acid, alkali metal malonates, fatty acid sulfonates, alkyl and alkenyl disuccinates, tartaric acid diacetate, tartaric acid monoacetate, oxidized starch, and polymeric builders, for example polycarboxylates and polyaspartic acid. Examples of organic builders are especially polymers and copolymers. In one embodiment of the present invention, organic builders are selected from polycarboxylates, for example alkali metal salts of (meth)acrylic acid homopolymers or (meth)acrylic acid copolymers, partially or completely neutralized with alkali. 24 Suitable comonomers for (meth)are monoethylenically unsaturated dicarboxylic acids such as maleic acid, fumaric acid, maleic anhydride, itaconic acid and citraconic acid. A suitable polymer is in particular polyacrylic acid, which preferably has an average molecular weight Mwin the range from 2000 to 40000 g / mol, preferably 3,000 to 10,000 g / mol. It is also possible to use copolymers of at least one monomer from the group consisting of mo- noethylenically unsaturated C3-C10-mono- or C4-C10-dicarboxylic acids or anhydrides thereof, such as maleic acid, maleic anhydride, acrylic acid, methacrylic acid, fumaric acid, itaconic acid and citraconic acid, with at least one hydrophilic or hydrophobic monomer as listed below. Suitable hydrophobic monomers are, for example, isobutene, diisobutene, butene, pentene, hexene and styrene, olefins with 10 or more carbon atoms or mixtures thereof, such as, for ex- ample, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 1- docosene, 1-tetracosene and 1-hexacosene, C22-α-olefin, a mixture of C20-C24-α-olefins and polyisobutene having on average 12 to 100 carbon atoms per molecule. Suitable hydrophilic monomers are monomers with sulfonate or phosphonate groups, and also nonionic monomers with hydroxyl function or alkylene oxide groups. By way of example, men- tion may be made of: allyl alcohol, isoprenol, methoxypolyethylene glycol (meth)acrylate, meth- oxypolypropylene glycol (meth)acrylate, methoxypolybutylene glycol (meth)acrylate, methoxy- poly(propylene oxide-co-ethylene oxide) (meth)acrylate, ethoxypolyethylene glycol (meth)acry- late, ethoxypolypropylene glycol (meth)acrylate, ethoxypolybutylene glycol (meth)acrylate and ethoxypoly(propylene oxide-co-ethylene oxide) (meth)acrylate. Polyalkylene glycols here may comprise 3 to 50, in particular 5 to 40 and especially 10 to 30 alkylene oxide units per molecule. Particularly preferred sulfonic-acid-group-containing monomers here are 1-acrylamido-1-pro- panesulfonic acid, 2-acrylamido-2-propanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylpropanesulfonic acid, 3-methacrylamido-2-hydroxypropane- sulfonic acid, allylsulfonic acid, methallylsulfonic acid, allyloxybenzenesulfonic acid, methallyl- oxybenzenesulfonic acid, 2-hydroxy-3-(2-propenyloxy)propanesulfonic acid, 2-methyl-2-pro- pene-1-sulfonic acid, styrenesulfonic acid, vinylsulfonic acid, 3-sulfopropyl acrylate, 2-sulfoethyl methacrylate, 3-sulfopropyl methacrylate, sulfomethacrylamide, sulfomethylmethacrylamide, and salts of said acids, such as sodium, potassium or ammonium salts thereof. Particularly preferred phosphonate-group-containing monomers are vinylphosphonic acid and its salts. 230235 25 Moreover, amphoteric polymers can also be used as builders. Inventive cleaning agents may comprise, for example, in the range from in total 10 to 50% by weight, preferably up to 20% by weight, of builder. In one embodiment of the present invention, inventive cleaning agents according to the inven- tion may comprise one or more cobuilders. Inventive cleaning agents may comprise one or more antifoams, selected for example from sili- cone oils and paraffin oils. In one embodiment of the present invention, inventive cleaning agents comprise in total in the range from 0.05 to 0.5% by weight of antifoam. Inventive cleaning agents may comprise one or more enzymes. Examples of enzymes are li- pases, hydrolases, amylases, proteases, cellulases, esterases, pectinases, lactases and perox- idases. In one embodiment of the present invention, inventive cleaning agents may comprise, for ex- ample, up to 5% by weight of enzyme, preference being given to 0.1 to 3% by weight. Said en- zyme may be stabilized, for example with the sodium salt of at least one C1-C3-carboxylic acid or C4-C10-dicarboxylic acid. Preferred are formates, acetates, adipates, and succinates. In one embodiment of the present invention, inventive cleaning agents may comprise at least one zinc salt. Zinc salts can be selected from water-soluble and water-insoluble zinc salts. In this connection, within the context of the present invention, water-insoluble is used to refer to those zinc salts which, in distilled water at 25°C, have a solubility of 0.1 g / l or less. Zinc salts which have a higher solubility in water are accordingly referred to within the context of the pre- sent invention as water-soluble zinc salts. In one embodiment of the present invention, zinc salt is selected from zinc benzoate, zinc glu- conate, zinc lactate, zinc formate, ZnCl2, ZnSO4, zinc acetate, zinc citrate, Zn(NO3)2, Zn(CH3SO3)2 and zinc gallate, preferably ZnCl2, ZnSO4, zinc acetate, zinc citrate, Zn(NO3)2, Zn(CH3SO3)2 and zinc gallate. In another embodiment of the present invention, zinc salt is selected from ZnO, ZnO·aq, Zn(OH)2 and ZnCO3. Preference is given to ZnO·aq. 230235 26 In one embodiment of the present invention, zinc salt is selected from zinc oxides with an aver- age particle diameter (weight-average) in the range from 10 nm to 100 µm. The cation in zinc salt can be present in complexed form, for example complexed with ammonia ligands or water ligands, and in particular be present in hydrated form. To simplify the notation, within the context of the present invention, ligands are generally omitted if they are water lig- ands. Depending on how the pH of mixture according to the invention is adjusted, zinc salt can change. Thus, it is for example possible to use zinc acetate or ZnCl2for preparing formulation according to the invention, but this converts at a pH of 8 or 9 in an aqueous environment to ZnO, Zn(OH)2 or ZnO·aq, which can be present in non-complexed or in complexed form. Zinc salt may be present in those inventive cleaning agents that are solid at room temperature. In such inventive cleaning agents zinc salts are preferably present in the form of particles which have for example an average diameter (number-average) in the range from 10 nm to 100 µm, preferably 100 nm to 5 µm, determined for example by X-ray scattering. Zinc salt may be present in those inventive cleaning agents that are liquid at room temperature. In such inventive cleaning agents zinc salts are preferably present in dissolved or in solid or in colloidal form. In one embodiment of the present invention, inventive cleaning agents comprise in total in the range from 0.05 to 0.4% by weight of zinc salt, based in each case on the solids content of the cleaning agent in question. Here, the fraction of zinc salt is given as zinc or zinc ions. From this, it is possible to calculate the counterion fraction. In one embodiment of the present invention, inventive cleaning agents are free from heavy met- als apart from zinc compounds. Within the context of the present, this may be understood as meaning that inventive cleaning agents are free from those heavy metal compounds which do not act as bleach catalysts, in particular of compounds of iron and of bismuth. Within the context of the present invention, "free from" in connection with heavy metal compounds is to be under- stood as meaning that the content of heavy metal compounds which do not act as bleach cata- lysts is in sum in the range from 0 to 100 ppm, determined by the leach method and based on the solids content. Preferably, inventive cleaning agents has, apart from zinc, a heavy metal 230235 27 content below 0.05 ppm, based on the solids content of the formulation in question. The fraction of zinc is thus not included. Within the context of the present invention, "heavy metals" are deemed to be all metals with a specific density of at least 6 g / cm3with the exception of zinc. In particular, the heavy metals are metals such as bismuth, iron, copper, lead, tin, nickel, cadmium and chromium. Preferably, inventive cleaning agents comprise no measurable fractions of bismuth compounds, i.e. for example less than 1 ppm. Inventive cleaning agents are excellent for cleaning hard surfaces and fibres. Some aspects of the present invention are illustrated by the following, non-limiting working examples. In a first row of orienting experiments in an intensive mixer (Eirich) and ploughshare mixer (Lö- dige), the addition of water was performed in an aqueous composition, comprising (besides wa- ter) a certain amountof foam-generating surfactant, which generates at least 100 ml of foam when measured according to EN 14371:20004 at 0.1 g / l, 25 °C, normal pressure and after 10 min in water. Without being bound to theory, it seems that due to the extended exposition of the MGDA containing particles in a wet environment, obviously, the surface of the larger particles became smooth and the finer particles have been taken up by the larger particles, where they obviously have been incorporated in the structure / morphology of the larger particles (see Fig- ures 1 and 2). These effects led to the desired mono-dispersity of the granules comprising MGDA and a polymer and to the desired increased particle density. No deposits on the mixer wall or on the mixer tools have been observed. In a second row of experiments, certain combinations of water with either (i) anionic or (ii) non- ionic surfactants were tested. In each case, a high bulk-density of the resulting granule could be detected. 2000 g of MGDA granules, resulting from spray granulation in a fluidized bed of a solution or slurry containing MGDA, were introduced into a a ploughshare mixer (Lödige mixer). Then, 100 g of a solution of 1 % by weight of a surfactant (see Table 1) was gradually sprayed over a peri- od of three minutes into the mixer through a foam-generating nozzle. The mixer was operated at a rotational speed of 300 rpm. The mixing was continued for another seven minutes at the same rotational speed. 230235 28 The product was removed from the vessel and the bulk density was measured, according to methods known to a person skilled in the art. (See, e. g., ScienceDirect, “Particle, Powder, and Compact Characterization, G.E. Amidon et al. in “Developing Solid Oral Dosage Forms, 2nded., 2017.) Table 1 Surfactant Foam generation* Bulk density (g / cm3) C8 to C10 alkylpolyglucoside with a1500 ml0.84degree of polymerization of 1.2 – 1.8 C8 to C14 alkylpolyglucoside with a1480 ml0.83degree of polymerization of 1.2 – 1.8 C16 to C18 ethoxylate with 25 EO320 ml0.83units Ethoxylate of 2-propylheptanol and1300 ml0.85C16 to C18 alcohol with 7 EO units Ethoxylate of 2-propylheptanol with 7550 ml0.86EO units Sulfated C12 to C14 ethoxylate with > 1500 ml0.852 EO units w / o - 0.74 * according to EN 14371:2004 at 0.1 g / l, 25 °C, normal pressure and after 10 min circulation in demineralized water The experiments show that the inventive process, which makes use of an aqueous composition comprising at least one surfactant, leads to a considerably improved (i. e. increased) bulk densi- ty in the resulting granules. Figures The figures show particles resulting from the inventive process (figure 2) and particles resulting from a comparative process (without use of inventive aqueous surfactant composition), showing also undesired fines (figure 1), wherein the comparative process lacks process step (c) as de- scribed in claim 1 below, i. e. the treatment of granules with a composition of surfactants. Figure 230235 29 3 shows schematically a mixer with a foam generating device, and figure 4 is a (schematic) de- piction of a foam nozzle.

Claims

Patent Claims 1. Process for making granules with high bulk density containing (A) at least one chelating agent selected from alkali metal salts of methyl glycine diace- tic acid (MGDA) and iminodisuccinic acid (IDS), and / or at least one polymer (PA), and, optionally, (B) at least one homo- or copolymer (PB), selected from the list consisting of (i) polyas- partates with an average molecular weight Mw in the range of from 1,000 to 20,000 g / mole, determined by gel permeation chromatography (GPC) and referring to the respective free acid, (ii) homo- or copolymers of (meth)acrylic acid, partially or fully neutralized with alkali, and (iii) graft copolymers comprising at least one graft base selected from nonionic mono-, di-, oligo- and polysaccharides and polymers P ob- tainable by grafting ethylenically unsaturated monomers M onto the graft base, wherein the monomers M comprise at least one monomer b1 selected from mo- noethylenically unsaturated mono- and dicarboxylic acids; and ) at least one mono- mer b2 selected from ethylenically unsaturated monomers having a permanent cati- onic charge, said process comprising the steps of (a) providing an aqueous solution or slurry containing chelating agent (A) and / or polymer (PA), and if applicable, (co)polymer (B), (b) removing most of said water by spray granulation in a fluidized bed, thereby obtaining a granule, (c) treating the resultant granule from step (b) with air or an inert gas in a vessel of which at least one part rotates around a horizontal or vertical axis and wherein said vessel is selected from high-speed mixers, paddle mixers, ploughshare mixers free-fall mixers, mixers with an additional chopper unit in- tensifying the mixing and mixers, wherein the vessel additionally contains an aqueous composition (AC) comprising at least one surfactant (S), wherein sur- factant (S) preferably generates at least 100 ml of foam when measured ac- cording to EN 14371:2004 at 0.1 g / l, 25 °C, normal pressure and after 10 min circulation in demineralized water, and wherein surfactant (S) is preferably se- lected from the list consisting of non-ionic surfactants (S1), anionic surfac- tants (S2), amphoteric surfactants (S3) and mixtures thereof, wherein the aqueous composition is preferably introduced through a foam generation noz- zle.

2. Process according to claim 1, wherein non-ionic surfactant (S1) is selected from al- kylpolyglycosides (APGs), alkoxylates and mixtures thereof.31 3. Process according to claim 1 or 2, wherein anionic surfactant (S2) is selected from sodium laurylsulfate (SLS), sodium laureth sulfate with 1 – 5 EO units and mixtures thereof.

4. Process according to any one of the preceding claims, wherein amphoteric surfactant (S3) is selected from acylamidopropylbetaines, preferably cocamidopropylbetaine.

5. Process according to any one of the preceding claims, wherein the aqueous composition (AC) contains between 0.01 and 10.00 % by weight of surfactant S, preferably 0.10 and 3.00 % by weight of surfactant S.

6. Process according to any one of the preceding claims, wherein between 1 and 20 % by weight of of aqueous composition (AC), preferably 2 to 10% by weight of aqueous compo- sition (AC), , is introduced into the vessel, relative to the total weight of the aqueous solu- tion or slurry containing chelating agent (A) and / or polymer (PA), if applicable, (co)polymer (B), after most of the water has been removed in step (b), wherein the aqueous composi- tion is preferably introduced through a foam generation nozzle.

7. Process according to any one of the preceding claims, wherein polymer (PA) is selected from the list consisting of (i) polyaspartates with an average molecular weight Mw in the range of from 1,000 to 20,000 g / mole, determined by gel permeation chromatography (GPC) and referring to the respective free acid, (ii) homo- or copolymers of (meth)acrylic acid, partially or fully neutralized with alkali, and (iii) graft copolymers comprising at least one graft base selected from nonionic mono-, di-, oligo- and polysaccharides and poly- mers P obtainable by grafting ethylenically unsaturated monomers M onto the graft base, wherein the monomers M comprise at least one monomer c1 selected from monoethyleni- cally unsaturated mono- and dicarboxylic acids; and ) at least one monomer c2 selected from ethylenically unsaturated monomers having a permanent cationic charge .

8. Process according to any one of the preceding claims, wherein the granule contains at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and iminodisuccinic acid (IDS) and, optionally, at least one homo- or copolymer (PB), but no polymer (PA).

9. Process according to any one of the preceding claims, wherein step (c) is performed in a temperature range of between -10°C and 200°C, preferably between 0°C and 100° C and / or in a pressure range in the vessel of between 0 bar (vacuum) and 100 bar, prefera- bly between 0.1 bar and 10 bar, and / or wherein the liquid passing the nozzle in step (c) is performed in a pressure range of between 0,1 bar and 100 bar, preferably performed be- tween 1 bar and 10 bar.

10. Process according to any one of the preceding claims, wherein step (c) is performed in that the mass ratio of the liquid and the gas passing the nozzle is in a range of between 0.001 kilogram of liquid per kilogram of gas and 1000 kilogram of liquid to 1 kilogram of230235 32 gas, preferably performed in a range of between 0.1 kilogram liquid per kilogram of gas and 10 kilogram of liquid to 1 kilogram of gas.

11. Process according to any one of the preceding claims, wherein step (c) is performed in that no gas passing the nozzle and only the liquid passing the nozzle is performed in a range of between 0.001 kilogram liquid per kilogram gas phase and 1000 kilogram liquid to 1 kilogram gas phase, preferably performed in a range of between 0.1 kilogram liquid per kilogram gas phase and 10 kilogram liquid to 1 kilogram gas phase.

12. Process according to any one of the preceding claims, wherein step (c) is performed in that the amount of liquid added per hour to the granules ranges is between 0.001 gram of liquid per 1 kilogram of solid per hour and 10 kilogram of liquid per 1 kilogram of solid per hour, preferably between 0.1 gram of liquid per 1 kilogram of solid per hour and 100 gram of liquid per 1 kilogram of solid per hour [kg_liquid / (kg_solid x h)].

13. Process according to any one of the preceding claims, wherein step (c) is performed with a mesh generating the foam at the foam nozzle tip, wherein the mesh size preferably is between 0.1µm and 10 mm.

14. Process according to any one of the preceding claims, wherein step (c) is performed over a period of 1 minute to 5 hours.

15. Process according to any one of the preceding claims, wherein step (c) is performed in a mixer.

16. Process according to any one of the preceding claims, wherein step (c) is followed by a step (d) including the removal of fines.

17. Use of an aqueous composition comprising at least one non-ionic surfactant (S1) and / or at least one anionic surfactant (S2) to increase bulk density of granules containing at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and iminodisuccinic acid (IDS), resulting from a spray granulation process, by generation of a foam in a vessel containing the granules of which at least one part rotates around a horizontal axis and wherein said vessel is selected from high-speed mixer, pad- dle mixers and free-fall mixers.

18. Granule containing at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and iminodisuccinic acid (IDS) and / or at least one polymer (PA), and, optionally at least one homo- or copolymer (PB) of (meth)acrylic acid with a comonomer bearing at least one sulfonic acid group per molecule, partially or fully neutralized with alkali, and / or, optionally, polyaspartates with an average molecular weight Mwin the range of from 1,000 to 20,000 g / mole, determined by gel permeation chromatography (GPC) and referring to the respective free acid,230235 33 in a weight ratio of chelating agent (A) to polymer(B) of from 2 : 1 up to 1,000 : 1, wherein said granule contains at least 75% by weight of chelating agent (A) and / or poly- mer (PA), and wherein said granule has an average broadness to length ratio in the range of from 1:1 to 1:0.

75.

19. Use of a granule according to claim 18, or obtained by a process according to any one of claims 1 to 16, for the manufacture of a cleaning agent, preferably for fibers or hard sur- faces, wherein said cleaning agent optionally contains at least one peroxy compound se- lected from percarbonates, persulfates and perborates.

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