WO2023126286A1

WO2023126286A1 - Multifunctional amphoteric hydrotropes, cleaning formulations containing them and use thereof

Info

Publication number: WO2023126286A1
Application number: PCT/EP2022/087371
Authority: WO
Inventors: Hanamanthsa Shankarsa Bevinakatti; Sorel MURESAN; Karen Lee White; Kevin Michael SALMON
Original assignee: Nouryon Chemicals International BV
Current assignee: Nouryon Chemicals International BV
Priority date: 2021-12-28
Filing date: 2022-12-21
Publication date: 2023-07-06
Anticipated expiration: 2024-06-28
Also published as: CN118382609A; EP4457208A1; JP2025501153A

Abstract

The present disclosure relates to compound of the formula (I) wherein R1 represents a fatty linear or branched, saturated or unsaturated alkylene group having 8-30 carbon atoms; R2 represents a linear or branched, saturated or unsaturated lower alkylene group having 1-8 carbon atoms; n represents 0 or 1; Z and Y independently represent a bond or a linear or branched lower alkylene group having 1-8 carbon atoms optionally substituted with one or more groups COOX3; and X1, X2, and X3 independently represent a negative charge or a counterion. The compound of formula (I) acts as a hydrotrope and is useful for cleaning applications. Processes of preparing the compound, cleaning compositions containing the compound, and methods of using the compound to clean an object are also disclosed.

Description

MULTIFUNCTIONAL AMPHOTERIC HYDROTROPES, CLEANING FORMULATIONS CONTAINING THEM AND USE THEREOF

PRIORITY CLAIM

[0001] This application claims priority of U.S. Provisional Application Serial No. 63/294,113, filed December 28, 2021, the entire contents of which are hereby incorporated herein by reference.

FIELD OF THE DISCLOSURE

[0002] The present disclosure relates to multifunctional hydrotropes and the use thereof in cleaning applications.

BACKGROUND OF THE DISCLOSURE

[0003] As is well-known in the art, many surfactants are too hydrophobic to be soluble in water. Attempts to introduce such surfactants to water can result in cloudy or hazy solutions. In order to solubilize such surfactants, typically a hydrotrope, for example, an amphoteric surfactant, must be added.

[0004] The amphoteric surfactants known in the prior art include alkylamine dipropionic acids and their salts. Alkylamine dipropionic acid products are commercially available from Nouryon (under the tradename AMPHOLAK®) and other producers. In these products, these amphoteric surfactants serve as good hydrotropes, particularly where the alkyl group is < Cl 2. However, these alkylamine dipropionic acids suffer from the drawback that they are prepared using acrylic acid, which is not bio-based. As a result, products containing these amphoteric surfactants have a low renewable carbon index (RCI).

[0005] Other amphoteric surfactants in use include ampho acetates made using monochloro acetic acid, preferably its sodium salt. They can be made using mono-, di-, tri-, and tetramines and are commercially available from Nouryon under the tradename AMPHOLAK®. However, such ampho acetates yield undesired NaCl as a byproduct. The presence of NaCl, an electrolyte, lowers the cloud point in the formulations, which is disadvantageous. Moreover, such products derived from tri- and tetramines are not readily biodegradable. [0006] Alkylamine dipropionic acids can be synthesized by reacting a primary fatty amine with acrylic acid via a Michael addition reaction. The product can be made/isolated either in its acid form or as a mono or disodium sodium salt by adding NaOH.

[0007] Itaconic acid (methylenebutanedioic acid, methylenesuccinic acid) is a crystalline, high melting acid (mp = 167 - 168°C) produced commercially by fermentation of carbohydrates and, thus, bio-based.

[0008] Itaconic acid cannot be simply substituted for acrylic acid in the process used to make alkylamine dipropionic acids and their salts because the reaction of itaconic acid with primary amines leads to lactam formation as soon as the desired product is formed due to a favored intramolecular dehydration reaction. The resulting lactam functions poorly as a hydrotrope due to insufficient hydrophilic character.

[0009] It is an object of the present disclosure to develop a bio-based multifunctional hydrotrope with low or no environmental persistence and ecotoxicity for cleaning formulations.

SUMMARY OF THE DISCLOSURE

[0010] The present disclosure relates in one embodiment to a compound of the formula (I):

wherein

Ri represents a fatty linear or branched, saturated or unsaturated alkylene group having 8-30 carbon atoms;

R2 represents a linear or branched, saturated or unsaturated lower alkylene group having 1-8 carbon atoms; n represents 0 or 1 ;

Z and Y independently represent a bond or a linear or branched lower alkylene group having 1-8 carbon atoms optionally substituted with one or more groups COOX3; and

Xi, X2, and X3 independently represent a negative charge or a counterion. [0011] Compounds wherein one or more of Xi, X2, and X3 represent H are also contemplated, particularly those wherein one of Xi and X2 represents H and the other represents a negative charge or a counterion.

[0012] The present disclosure relates in another embodiment to a process for preparing a compound according to any one of claims 1-6, said process comprising:

(a) reacting a multicarboxylic acid of the formulae:

wherein represents a linear or branched lower alkyl group having 1 to 8 carbon atoms; and represents 0 or 1 ; or a salt or ester thereof with a secondary amine of the formula:

(b) optionally at least partially neutralizing with base.

[0013] The present disclosure relates in another embodiment to an aqueous cleaning composition comprising:

(a) at least one compound of formula (I) as described herein; and

(b) water.

[0014] The present disclosure relates in yet another embodiment to a method of cleaning an object to be cleaned comprising contacting the object with an aqueous cleaning composition as described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The disclosure will now be described in greater detail with reference to the drawings, wherein:

FIG. 1A is an illustration depicting the cleaning power of ARMEEN® 1M1214D itaconate (C12-14 alkyl methyl amine itaconate) versus the control “A” (BEROL® R648 NG (quaternary C12-14 alkyl methyl amine ethoxylate methyl chloride)) in the absence of NaOH on a plate soiled with engine grease; and

FIG. IB is an illustration depicting the cleaning power of ARMEEN® 1M1214D itaconate versus the control “C” (BEROL® R648 NG) in the presence of 2% NaOH on another plate soiled with engine grease.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The compound of formula (I) can be derived from any multicarboxylic acid containing a carbon-carbon double bond.

[0017] In a preferred embodiment, the compound of formula (I) is derived from a multicarboxylic acid of the formulae:

[0018] In an especially preferred embodiment, the multicarboxylic acid is selected from the group consisting of itaconic acid, methylidenemalonic acid, methylideneglutaric acid, maleic acid, fumaric acid, citraconic acid, and mesaconic acid.

[0019] The carboxylic acid functionality can be partially or completely neutralized in Xi, X2, X3 etc., with any suitable cations, especially, an alkaline (earth) metal ion, such as Mg²⁺, Ca²⁺, NH₄ ⁺, K⁺ or Na⁺, especially sodium and potassium, most preferably sodium, or an alkanolamine, such as methanolamine, monoethanolamine (MEA), diethanolamine (DEA) triethanolamine (TEA), 2-amino-2-methyl-l -propanol (AMP), tris(hydroxymethyl)aminomethane (TRIS), or 2-(isopropylamino)ethanol (IPAE).

Neutralization can be conducted using neutralization methods well known in the art, for example, reaction with sodium hydroxide or other suitable neutralizing agents. [0020] In a preferred embodiment, the compound of formula (I) is also derived from a secondary amine of the formula:

wherein

Ri represents a fatty linear or branched, saturated or unsaturated alkylene group having 8-14 carbon atoms; and

R2 represents a linear or branched, saturated or unsaturated lower alkylene group having 1-3 carbon atoms.

[0021] In an especially preferred embodiment, the secondary amine is selected from the group consisting of octylmethylamine, cocoalkylmethylamine, laurylmethylamine, n- decylmethylamine, tallowalkylmethylamine, soyaalkylmethylamine, oleylalkylamine and C 12/ 14alkylmethy lamine.

[0022] In a more preferred embodiment, the compound of formula (I) has the formula:

wherein

Ri represents a fatty linear or branched, saturated or unsaturated alkylene group having 12 or 14 carbon atoms; and

Xi and X2 independently represent a negative charge or a counterion.

[0023] In a most preferred embodiment, in the immediately preceding formula, at least one of Xi or X2 is a sodium cation.

[0024] In an alternative embodiment, in the immediately preceding formula, one of Xi and X2 represents H and the other represents a negative charge or a counterion, especially sodium.

[0025] As noted above, the compound of the formula (I) is prepared by a process comprising:

(a) reacting a multicarboxylic acid of the formulae:

or a salt or ester thereof with a secondary amine of the formula:

(b) optionally at least partially neutralizing with base.

[0026] In the process, two different modes of addition are contemplated. In a first embodiment, the secondary amine is added to a reaction mixture containing the multicarboxylic acid. In a second embodiment, the multicarboxylic acid is added to a reaction mixture containing the secondary amine.

[0027] The neutralization of the multicarboxylic acid can be carried out either before (preneutralization) the reaction with the secondary amine or afterwards (post- neutralization). In one embodiment, the reaction is carried out in the absence of NaOH, leading to acid product characterized by the presence of COOH groups. In another embodiment, the reaction is carried out using 1 equivalent of NaOH, giving rise to monosodium salts. In yet another embodiment, the reaction is carried out using 2 equivalents of NaOH, giving rise to disodium salts. The present disclosure seeks to cover any degree of partial neutralization, i.e., from unneutralized, to any extent of partial neutralization, to completely neutralized. In the most preferred embodiment, the product is a monosodium salt.

[0028] Besides the multicarboxylic acid and the secondary amine, the reaction mixture will contain water alone or a mixture of water and suitable organic solvent, for example, an alcohol, such as ethanol or methanol, or a glycol such as ethylene glycol, monopropylene glycol (MPG) or glycerol, with MPG being most preferred, followed by glycerol. The amount of solvent is preferably 0-80 wt% of the reaction mixture, most preferably 40-60 wt%. In one preferred embodiment, the solvent is removed from the product. In another preferred embodiment, the solvent is not removed and is, therefore, present in the product.

[0029] Typically, catalysts are not needed, but the use of suitable catalysts is also contemplated. [0030] The temperature can range from 25-110°C, or higher, depending on the reactants. In the case of the reaction of itaconic acid and ARMEEN® 1M1214D, reactions carried at temperatures greater than 110°C lead to side products and, therefore, the temperature should be kept lower. On the other hand, temperatures lower than 70 °C lead to long reaction times and incomplete reactions. Preferably the reaction with itaconic acid and ARMEEN® 1M1214D is carried out at 70-85°C for up to 10 hours.

[0031] The process of the reaction can be monitored using IR and/or Raman spectroscopy, or HPLC. Purity and composition of the resultant product can be analyzed using Hl and Cl 3 NMR, or LC-MS.

[0032] In some cases, the product obtained may be a mixture of expected product plus both the unreacted starting materials. A molar excess of up to 25%-50% of itaconic acid can be used to reduce the amount of unreacted alkyl amine. Even with 25% molar excess of itaconic acid, the product still contains some residual amine. However, the resulting product gives good performance. Having too much of alkyl amine content in the product is disadvantageous because, being hydrophobic, the unreacted amine remains insoluble in the formulation. Since itaconic acid is water-soluble and water is the major component of the formulation, having excess itaconic acid remaining in the product is not so much of a problem as having unreacted secondary amine.

[0033] The active% of the product is preferably 20-100%, most preferably 40-60%.

[0034] Cleaning formulations containing the disclosed compounds are useful for a variety of cleaning purposes, for example, they can be formulated for, household cleaning, industrial cleaning, all-purpose cleaning, car washing, acidic and caustic cleaning, deck and floor cleaning, hard surface cleaning, metal cleaning, food & beverage cleaning, automated and manual dishwash, laundry detergents and the like.

[0035] For such purposes, the cleaning formulations may contain, in addition to the disclosed compounds of formula (I) and water, other conventional ingredients well known in the art of cleansing.

[0036] In a preferred embodiment, the cleaning composition comprises one or more nonionic surfactants.

[0037] In a more preferred embodiment, the one or more nonionic surfactants are selected from the group consisting of nonionic alkylene oxide adducts, especially C8-C18-linear and branched alcohol (alcohol alkoxylates) and amine alkoxylates comprising 1-20 ethyleneoxy units and 0-5 propyleneoxy units. The non-ionic alkyl polyglyceryl ethers made using C8- C18-linear and branched alcohol and 1-10 glycidol units or alkyl polyglycerylamines made using C8-C18-linear and branched alkyl amine and 1-10 glycidol units can also be used.

[0038] The nonionic alkylene oxide adducts are well known conventional products wherein the molecule comprises a hydrophobic moiety and a moiety containing alkyleneoxy units, said latter moiety having a hydrophilic character. Thus the disclosure relates to the use of compounds of formula (I) as hydrotropes for nonionic surfactants in aqueous solutions. In other words, the disclosure relates to the improved solubilization of nonionic surfactants to make compositions with a good cleaning performance wherein water, a nonionic surfactant, a compound having the formula (I) as defined above, and other optional ingredients are combined and/or mixed in one or several steps.

[0039] The amounts of the components are suitably: a) at least 0.05% by weight, preferably at least 0.5% by weight, and at most 20% by weight, preferably at most 15% by weight, and most preferably at most 10% by weight, of alcohol alkoxylate, b) at least 0.02% by weight, preferably at least 0.1% by weight, and at most 20% by weight, preferably at most 15% by weight, and most preferably at most 10% by weight, of compound of formula (I), and c) 0% by weight, preferably at least 0.05% by weight, and at most 30% by weight, preferably at most 20% by weight, more preferably at most 15% by weight, and most preferably at most 10% by weight, of alkali hydroxides, alkaline builders and/or alkaline complexing agents.

[0040] It is especially preferred that the compositions contain alkali hydroxides, alkaline builders and/or alkaline complexing agents.

[0041] The nonionic surfactants preferably have the formula:

R₃O - (PO)x(EO)y(PO)zH (II) wherein R₃ is a C8 to C18 linear or branched alkyl group, preferably C8 to C12; PO is a propyleneoxy unit, EO is an ethyleneoxy unit, x = 0-5, preferably 0-4, and most preferably 0- 2; y = 1-20, preferably 1-12, more preferably 2-8, and most preferably 2-5; and z = 0-5, preferably 0-4, more preferably 0-2, and most preferably 0. Thus, in addition to the 1-20 ethyleneoxy units, the C8-C18-alcohol alkoxylates may also contain up to 5 propyleneoxy units. The number of propyleneoxy units, when present, may be as small as 0.1 mole PO per mole alcohol. The ethyleneoxy units and the propyleneoxy units may be added randomly or in blocks. The blocks may be added to the alcohol in any order. The alkoxy lates may also contain an alkyl group with 1-4 carbon atoms in the end position. Preferably, the alkoxylates contain 2-8 ethyleneoxy units and 0-2 propyleneoxy units. The alkyl group of the nonionic surfactants may be linear or branched, saturated or unsaturated. Suitable linear nonionic surfactants are C9-C11 alcohol + 4, 5, 6, 7 or 8 moles of EO, C8-C10 alcohol + 3, 4, 5, 6, 7 or 8 moles of EO, C12-C14 alcohol + 3, 4, 5, 6, 7 or 8 moles of EO and C10-C14 alcohol + 8 moles of EO + 2 moles of PO. Suitable branched nonionic surfactants are 2-ethylhexanol + 3, 4 or 5 moles of EO, 2-ethylhexanol + 2 moles of PO + 4, 5 or 6 moles of EO, 2- propylheptanol + 3, 4, 5 or 6 moles of EO and 2-propylheptanol + 1 mole of PO + 4 moles of EO, C9 or Cll alcohol + 4, 5, 6, 7 or 8 moles of EO, tridecyl alcohol + 4, 5, 6, 7 or 8 moles of EO,. Another example is 2-butyloctanol + 5, 6 or 7 moles of EO. Wherever the degree of alkoxylation is discussed, the numbers represent molar average numbers.

[0042] The compositions may be acidic, neutral or alkaline. Alkaline compositions are typically based on alkali hydroxides, alkaline builders and/or complexing agents. The alkaline compositions are especially preferred.

[0043] The alkali hydroxides preferably are sodium or potassium hydroxide. The alkaline builders may be an alkali carbonate or an alkali hydrogen carbonate, such as sodium carbonate, potassium carbonate, sodium hydrogen carbonate or potassium hydrogen carbonate, an alkali salt of a silicate, such as sodium silicate or sodium metasilicate, or alkali salts of phosphates, such as sodium orthophosphate. Alkaline builders that act through complexation are, e.g., sodium pyrophosphate and sodium tripolyphosphate and the corresponding potassium salts. The builder/complexing agent may also be organic. Examples of organic builders/complexing agents are aminocarboxylates, such as Glutamic acid, N,N- diacetate (GLDA), Methylglycine, N,N-diacetate (MGDA), sodium nitrilotriacetate (Na3NTA), sodium ethylenediamine tetraacetate (EDTA), sodium diethylenetriamine pentaacetate, sodium 1,3 -propylenediamine tetraacetate, and sodiumhydroxyethylethylenediamine triacetate; aminopolyphosphonates, such as nitrilotrimethylene phosphonate; organic phosphates; polycarboxylates, such as citrates; and alkali salts of gluconic acid, such as sodium or potassium gluconates.

[0044] In neutral and acidic compositions complexing and/or pH adjusting agents may also be added, such as citric acid, oxalic acid, acetic acid, sulfamic acid, hydrochloric acid.

[0045] In another preferred embodiment, the cleaning composition comprises one or more chelates. [0046] In one embodiment, the chelate is at least one aminocarboxylate chelate selected from the group consisting of methylglycinediacetic acid (MGDA), N,N-dicarboxymethyl glutamic acid (GLDA), N-hydroxyethyliminodiacetic acid, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), N-hydroxyethyl-ethylenediaminetriacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTP A), ethylenediaminetetraproprionic acid triethylenetetraaminehexaacetic acid (TTHA), tetracetyl ethylene diamine (TAED), iminodisuccinic acid (IDS), ethanol diglycine (EDG), and the respective alkali metal, ammonium and substituted ammonium salts thereof. In a particularly preferred embodiment, the aminocarboxylate chelate is selected from the group consisting of EDTA, GLDA, MGDA, salts thereof, and combinations thereof.

[0047] In another embodiment, the chelate is a non-aminocarboxylate chelate containing carboxylate functionality but not a nitrogen atom. In a preferred embodiment, the non- aminocarboxylate chelate is a divalent or higher valency carboxylic acid. In an especially preferred embodiment, the non-aminocarboxylate chelate is at least one member selected from the group consisting of citric acid, isocitric acid, 2,3 hydroxycitric acid, tricarballylic acid, ethanetricarboxylic acid (HETA), aconitic acid, succinic acid, maleic acid, fumaric acid, oxaloacetic acid, ketoglutaric acid, butanetetracarboxylic acid, polycarboxylic acid, and the respective alkali metal, ammonium and substituted ammonium salts thereof. In a particularly preferred embodiment, the non-aminocarboxylate chelate is selected from the group consisting of citric acid and salts thereof.

[0048] When one or more chelates are present in the formulation, they are present in a total combined chelate amount of greater than 0% by weight, preferably at least 0.05% by weight, most preferably at least 1% by weight, and at most 30% by weight, preferably at most 20% by weight, more preferably at most 15% by weight, and most preferably at most 10% by weight.

[0049] In another preferred embodiment, in addition to one or more nonionic surfactants and/or chelates, the cleaning composition further comprises one or more adjunct ingredients selected from the group consisting of aesthetic agents, anti-filming agents, anti-redeposition agents, anti-spotting agents, anti-graying agents, beads, binders, biocides, bleach activators, bleach catalysts, bleach stabilizing systems, bleaching agents, brighteners, buffering agents, builders, carriers, clay, color speckles, control release agents, corrosion inhibitors, dish care agents, disinfectants, dispersant agents, draining promoting agents, drying agents, dyes, dye transfer inhibiting agents, enzymes, enzyme stabilizing systems, fillers, free radical inhibitors, fungicides, germicides, hydrotropes other than those of formula (I), opacifiers, perfumes, pH adjusting agents, pigments, processing aids, silicates, soil release agents, suds suppressors, anionic surfactants, cationic surfactants, stabilizers, thickeners, zeolite, and mixtures.

[0050] When one or more adjunct ingredients are present in the formulation, they are present in a total combined adjunct ingredient amount of greater than 0% by weight, preferably at least 0.05% by weight, most preferably at least 1% by weight, and at most 30% by weight, preferably at most 20% by weight, more preferably at most 15% by weight, and most preferably at most 10% by weight.

[0051] The present disclosure contemplates both diluted and concentrated compositions.

[0052] Diluted compositions of the present disclosure are clear and stable. The clarity interval suitably is between 0-40°C, preferably between 0-50°C, and most preferably between 0-60 °C. This may be adapted by changing the ratio of hydrotrope to nonionic surfactant. The diluted compositions normally contain at least 80% by weight of water, suitably at least 90% by weight, and normally at most 99.5% by weight of water, suitably at most 98% by weight.

[0053] Concentrated compositions of the present disclosure are clear and stable. The clarity interval suitably is between 0-40°C, preferably between 0-50°C, and most preferably between 0-60 °C. This may be adapted by changing the ratio of hydrotrope to nonionic surfactant. The concentrate normally contains at least 50% by weight of water, suitably at least 70% by weight, and normally at most 95% by weight of water, suitably at most 90% by weight.

[0054] There are several advantages connected with the use of the compounds of formula (I) as hydrotropes for nonionic surfactants. Firstly, they are excellent hydrotropes that also contribute to the cleaning performance of the compositions. Their cleaning efficiency is very good even at high dilutions of the compositions. Further, their biodegradability is expected to be better than that of previously known compounds, for example, BEROL® R648 NG (Nouryon) used in compositions for cleaning hard surfaces.

[0055] The disclosure will now be described in greater detail with reference to the following non-limiting examples. Examples

Example 1: ARMEEN® 1M1214D Monosodium Itaconate

[0056] ARMEEN® 1M1214D monosodium itaconate can be prepared according to the following synthesis scheme:

[0057] In greater detail, ARMEEN® 1M1214D monosodium itaconate can be prepared as follows:

[0058] Step-1: ARMEEN® 1M1214D (C12-14 alkyl methyl amine/Nouryon) and monopropylene glycol (MPG) were added to a 100 ml 3 -neck RB flask immersed in an oil batch fitted with magnetic stirrer, thermometer, N2 inlet (sparge) and a reflux condenser, and stirred at room temperature (RT) while sparging N2. Solid itaconic acid was added to the stirred reaction mixture and the reaction mixture temperature was set to 80°C. Stirring is continued until the reaction is complete as monitored by infrared spectra (IR) as assessed by the disappearance of the peak corresponding to C=C or no further change in IR.

[0059] Step-2: Once the reaction is complete, water is added to the reaction mixture followed by slow addition of 50% NaOH solution from a disposable pipette keeping the reaction mixture temperature <80°C. The reaction mixture is well stirred after the addition and the product is transferred to ajar.

[0060] The resulting product is 50% active in 50:50 MPG + H2O.

Example 2: ARMEEN® 1M1214D Monosodium Itaconate

[0061] Step-1: ARMEEN® 1M1214D and MPG were added to a 100 ml 3-neck RB flask immersed in an oil batch fitted with magnetic stirrer, thermometer, N2 inlet (sparge) and a reflux condenser, and stirred at room temperature while sparging N2. Dimethyl itaconate was slowed added to the reaction mixture, while checking for any exotherm, and the reaction mixture temperature was set to 50°C. Stirring is continued until the reaction is complete as monitored by infrared spectra (IR) as assessed by the disappearance of the peak corresponding to C=C or no further change in IR. (The reaction temperature can be increased in 10°C increments as required until the reaction is complete.) [0062] Step-2: Once the reaction shows completion, water and aq. NaOH are added and the reaction mixture is stirred at ~70°C until the hydrolysis shows completion as monitored by IR for the disappearance of the ester carbonyl, at which time the product is transfer to ajar.

[0063] The resulting product is 50% active in MPG + H2O + MeOH.

Example 3: ARMEEN® 1M1214D Monosodium Fumarate

[0064] Step- 1 : Fumaric acid and water were added to a 100 ml 3 -neck RB flask immersed in an oil batch fitted with magnetic stirrer, thermometer, N2 inlet and a reflux condenser, and stirred at room temperature under N2 sparging. NaOH was added to the stirred fumaric acid solution and stirred well (exothermic). Once the reaction mixture became clear, MPG was added to the reaction mixture and the reaction temperature was set to 75 °C and IR taken once the reaction mixture became clear again.

[0065] Step 2: Once the temperature of the reaction mixture stabilized at ~75°C, the amine was slowly added, keeping the temp <80°C, and the temperature of the reaction mixture was set to 80°C. Progress of the reaction was monitored by IR until completion was indicated by disappearance of C=C and or stabilization of other peaks. Once the reaction was complete, the product was transferred to ajar.

[0066] The resulting product is 50% active in MPG + water.

[0067] Example 4

[0068] In an analogous manner, amphoteric surfactants can be made from the following combinations of secondary amines and multicarboxylic acids:

Example 5

[0069] BEROL® R648 NG (Nouryon) is a market leading product for cleaning formulations that afford best-in-class cleaning, from a renewable, vegetable source with low or no environmental persistence and ecotoxicity and ideally non-label as-sold. Though BEROL® R648 NG is readily biodegradable, it has certain drawbacks such as, it is an ethoxylate (not dioxane- free), is a quat, and has low RCI (Renewable Carbon Index) of 29%. With the fast changing regulations and environmental awareness, the availability of an EO-free (and dioxane free) non-quat product with higher RCI (preferably >50%) that performs as well as BEROL® R648 NG is desired.

[0070] ARMEEN® 1M1214D itaconate meets all the criteria mentioned above with performance as good as the benchmark BEROL® R648 NG. ARMEEN® 1M1214D itaconate is expected to be readily biodegradable with high RCI (-95%), low/no toxicity, and cleaning performance as good as the benchmark BEROL® R648 NG.

[0071] The suitability of ARMEEN® 1M1214D itaconate to solubilize BEROL® 260 (C9- C11 alcohol ethoxylate) and the cleaning power of the resultant formulations were tested in comparison to BEROL® R648 NG. Test formulations A and B comprised 5% BEROL® 260, 8% DISSOLVINE® GL-47-S, and either 4% BEROL® R648 NG or 2.4% ARMEEN® 1M1214D itaconate, respectively. Test formulations C and D comprised 5% BEROL® 260, 8% DISSOLVINE® GL-47-S, 2% NaOH, and either 4% BEROL® R648 NG or 2.4% ARMEEN® 1M1214D itaconate, respectively.

[0072] The degreasing effect of the test formulations was assessed on a white painted metal plate soiled uniformly with a tough-to-clean greasy soil collected from a train engine. The cleaning formulation (1:40 dilution in water) was applied simply by pouring it over the surface (non-mechanical cleaning). After a short time interval, the whole plate was rinsed with tap water and cleaning performance was assessed quantitatively. The results are tabulated below and depicted in FIG. 1A (for the respective cleaning formulations A and B containing no NaOH) and FIG. IB. (for the respective cleaning formulations C and D containing 2% NaOH).

[0073] The data in the foregoing table and in FIG. 1A and FIG. IB show the inventive hydrotrope (ARMEEN® 1M1214D itaconate) performs as well as the comparison hydrotrope (BEROL® R648 NG) in the absence or presence of NaOH in the cleaning formulation.

[0074] While the present disclosure has been described in conjunction with the specific embodiments set forth above, many alternatives, modifications and other variations thereof will be apparent to those of ordinary skill in the art. All such alternatives, modifications and variations are intended to fall within the spirit and scope of the present disclosure.

Claims

WHAT IS CLAIMED:

1. A compound of the formula (I):

wherein

Xi, X2, and X3 independently represent a negative charge or a counterion.

2. The compound according to claim 1, which is derived from a multicarboxylic acid of the formulae:

wherein

W represents a linear or branched lower alkyl group having 1 to 8 carbon atoms; and m represents 0 or 1 ; or a salt or ester thereof.

3. The compound according to claim 2, wherein the multicarboxy he acid is selected from the group consisting of itaconic acid, methylidenemalonic acid, methylideneglutaric acid, maleic acid, fumaric acid, citraconic acid, and mesaconic acid.

4. The compound according to any one of claims 1-3, which is derived from a secondary amine of the formula:

wherein

5. The compound according to claim 4, wherein the secondary amine is selected from the group consisting of octylmethylamine, cocoalkylmethylamine, laurylmethylamine, n-decylmethylamine, tallowalkylmethylamine, soyaalkylmethylamine, and C12/14alkylmethylamine.

6. The compound according to claim 1, which has the formula:

wherein

Xi and X2 independently represent a negative charge or a counterion.

7. A process for preparing a compound according to any one of claims 1-6, said process comprising:

(a) reacting a multicarboxylic acid of the formulae:

wherein

W represents a linear or branched lower alkyl group having 1 to 8 carbon atoms; and m represents 0 or 1 ; or a salt or ester thereof with a secondary amine of the formula:

(b) optionally at least partially neutralizing with base.

8. The process according to claim 7, which further comprises at least partially neutralizing with base, wherein the base is sodium hydroxide.

9. An aqueous cleaning composition comprising:

(a) at least one compound according to any one of claims 1-6; and

(b) water.

10. The aqueous cleaning composition according to claim 9, which further comprises one or more nonionic surfactants.

11. The aqueous cleaning composition according to claim 9 or 10, which further comprises one or more chelates.

12. The aqueous cleaning composition according to any one of claims 9-11, which further comprises one or more adjunct ingredients selected from the group consisting of aesthetic agents, anti-filming agents, anti-redeposition agents, anti-spotting agents, anti-graying agents, beads, binders, biocides, bleach activators, bleach catalysts, bleach stabilizing systems, bleaching agents, brighteners, buffering agents, builders, carriers, clay, color speckles, control release agents, corrosion inhibitors, dish care agents, disinfectants, dispersant agents, draining promoting agents,

18 drying agents, dyes, dye transfer inhibiting agents, enzymes, enzyme stabilizing systems, fillers, free radical inhibitors, fungicides, germicides, hydrotropes other than those of formula (I), opacifiers, perfumes, pH adjusting agents, pigments, processing aids, silicates, soil release agents, suds suppressors, anionic surfactants, cationic surfactants, stabilizers, thickeners, zeolite, and mixtures thereof.

13. A method of cleaning an object to be cleaned comprising contacting the object with an aqueous cleaning composition according to any one of claims 9-12.

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