LIQUID AQUEOUS STAIN REMOVER FOR OILY OR GREASY STAINS

Description

[0001] The present invention relates to a liquid aqueous stain remover for use on textiles, its use for the removal of oily or greasy stains on textiles and a method of removing oily or greasy stains on textiles.

[0002] Greasy or oily stains are difficult to remove from fabrics in an ordinary laundry washing process, especially when cold wash conditions are applied, eg. washing the fabrics at 20°C. There are laundry pre-treatment products available, such as sprays or pads, which can help to attain the desired result but sometimes fail to remove the soils to the consumer's satisfaction. Washing the fabrics at higher temperatures is sometimes not possible because of the delicate nature of the textile, or it is not desired for ecological reasons. There remains, therefore, a need to provide improved removal of greasy or oily stains from fabric which is then washed in cold water at 20°C.

[0003] It was surprisingly found that an alkaline liquid aqueous stain remover comprising 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and a combination of an amine oxide and a fatty alcohol alkoxylate surfactant provided significantly improved oily stain removal in cold water washing even with lower surfactant concentrations than employed in market formulations.

[0004] In a first aspect the invention therefore relates to a liquid aqueous stain remover for use on textiles comprising at least one amine oxide and at least one fatty alcohol ethoxylate, characterized in that it additionally comprises 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and has a pH value of 9,5 to 10,5.

[0005] In a second aspect the invention relates to the use of a liquid stain remover according to the present invention for the removal of oily or greasy stains from textiles.

[0006] In a third aspect the invention also encompasses a product consisting of a liquid aqueous stain remover according to the present invention and a spray dispenser.

[0007] In yet another aspect the invention is directed towards a method of removing oily or greasy stains from items of clothing or other textiles comprising the following steps:

a) Bringing the stained fabric in contact with a liquid aqueous stain remover according to the invention, preferably by spraying the stain remover onto the fabric,

b) Waiting for 2 to 10 minutes, preferably for 5 minutes,

c) Washing the fabric, preferably in a washing machine and preferably at 20°C.

[0008] "At least one", as used herein, relates to one or more, i.e. 1, 2, 3, 4, 5, 6, 7, 8, 9, or more. If used in combination with a compound or component, the term does not relate to the absolute number of molecules but rather to the number of different types of said compound or component.

[0009] "Consists essentially of", as used herein, means that the respective composition comprises at least 50 wt.-%, preferably at least 70 wt.-%, more preferably at least 80 wt.-% of the given components. The residual amount may be made up by non-specified further ingredients. It may be preferred that these further ingredients do not comprise active ingredients.

[0010] If not indicated otherwise, all percentages are by weight relative to the total weight of the composition. "About" or "approx.", as used herein in relation to a numerical value, means said value ± 10 %, preferably ± 5 %. If a numerical value is given without any decimal place, such as "99 %", this refers to "99.0 %", if not indicated otherwise.

[0011] These and other aspects, features and advantages of the invention become apparent to the skilled person in the following detailed description and claims. Each feature from one aspect of the invention can be used in any other aspect of the invention. Furthermore, the examples contained herein are intended to describe and illustrate the invention, but do not restrict it. In particular, the invention is not limited to these examples.

[0012] The liquid aqueous stain remover described herein comprises at least one amine oxide. In principle, all amine oxides established for these purposes in the prior art, therefore compounds having the formula R¹R²R³NO, where each R¹, R², and R³ independently of the others is an optionally substituted C₁-C₃₀ hydrocarbon chain, can be used in this regard. Amine oxides, used especially preferably, are those in which R¹ is C₁₂-C₁₈ alkyl and R² and R³ are each independently C₁-C₄ alkyl, particularly C₁₂-C₁₈ alkyl dimethylamine oxides. Exemplary representatives of suitable amine oxides are N-coco alkyl-N,N-dimethylamine oxide, N-tallow alkyl-N,N-dihydroxyethylamine oxide, myristyl-/cetyldimethylamine oxide, or lauryldimethylamine oxide, of which lauryldimethylamine oxide is preferred.

[0013] In preferred embodiments, the at least one amine oxide is present in the liquid aqueous stain remover in an amount of 0.1% by weight to 5% by weight, preferably 0.5% by weight to 4% by weight, more preferably 0.8% by weight to 2% by weight, for example 1% by weight, given as the amount of active substance and based on the total weight of the composition.

[0014] Furthermore, the liquid aqueous stain remover comprises at least one fatty alcohol ethoxylate, available from the reaction of fatty alcohols with ethylene oxide (EO). Preferred fatty alcohol ethoxylates are nonionic surfactants of the formula

         R-O-(EO)_m-H,

in which

R

stands for a linear, unsubstituted alkyl group,

EO

stands for an ethylene oxide (EO) group,

m

stands for integers from 1 to 50.

[0015] Preferred R groups are derived from C_8-20 fatty alcohols, more preferably from C_10-16 fatty alcohols, especially from C_12-14 fatty alcohols, for example, from coconut fatty alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl, or stearyl alcohol.

[0016] EO stands for an ethylene oxide group, preferably for an ethylene oxide group. The subscript m stands for an integer from 1 to 50, preferably from 2 to 20, more preferably from 4 to 15, and especially from 6 to 10.

[0017] It is preferred that the at least one fatty alcohol ethoxylate is a C_8-20, preferably C_10-16, more preferably C_12-14 fatty alcohol ethoxylated with 2-20 moles of EO, preferably 4-15 EO, more preferably 6-10 EO. Most preferably, the at least one fatty alcohol ethoxylate is lauryl alcohol ethoxylate with 7 EO (laureth-7).

[0018] In preferred embodiments, the at least one fatty alcohol ethoxylate is present in the liquid aqueous stain remover in an amount of 0.5 % by weight to 8% by weight, preferably 1% by weight to 6% by weight, more preferably 2% by weight to 4% by weight, for example 3% by weight, given as the amount of active substance and based on the total weight of the composition.

[0019] The liquid aqueous stain remover additionally comprises 1-hydroxyethane-1,1-diphosphonic acid (HEDP). It was found that this chelating agent leads to an improved oily stain removal performance compared to other commonly used complexing agents such as ethylenediamine tetraacetic acid (EDTA), N,N-bis(carboxymethyl)-L-glutamate (GLDA) or methylglycin diacetate (MGDA).

[0020] An alkaline pH also leads to improved oily stain removal. However, a highly alkaline formula might cause fabric damage. A pH of 9 or less, on the other hand, leads to less than satisfactory results regarding oily stain removal performance. The liquid aqueous stain remover described herein therefore has a pH value of from 9.5 to 10.5.

[0021] This pH value is achieved through the addition of one or more alkaline pH adjusting agents. Suitable pH adjusting agents include alkali metal, alkaline earth metal or ammonium salts, such as hydroxides or carbonates, as well as amines. A preferred pH adjusting material is monoethanol amine (MEA). In a preferred embodiment the liquid aqueous stain remover therefore contains monoethanol amine as a pH regulator. Preferably the liquid aqueous stain remover contains MEA in an amount of at least 1 wt.-%, relative to the total weight of the composition.

[0022] In addition, the detergent can contain further ingredients that further improve the application and/or aesthetic properties of the detergent. Within the scope of the present invention, the detergent contains preferably in addition one or more substances from the group comprising other surfactants, builders, nonaqueous solvents, electrolytes, pH adjusting agents, fragrances, antiredeposition agents, antimicrobial substances, germicides, fungicides, antioxidants, preservatives, corrosion inhibitors and bitter agents.

[0023] The liquid aqueous stain remover may comprise additional surfactants, selected from the group consisting of non-ionic surfactants, anionic surfactants, amphoteric surfactants and cationic surfactants.

[0024] All nonionic surfactants known to one skilled in the art can be used as nonionic surfactants. Suitable nonionic surfactants are, for example, alkyl glycosides of the general formula RO(G)_x in which R denotes a primary straight-chain or methyl-branched, especially methyl-branched in the 2-position, aliphatic residue having 8 to 22, by preference 12 to 18 carbon atoms, and G is the symbol denoting a glycose unit having 5 or 6 carbon atoms, by preference glucose. The degree of oligomerization x, which indicates the distribution of monoglycosides and oligoglycosides, is any number between 1 and 10; by preference, x is 1.2 to 1.4.

[0025] Further nonionic surfactants which can be used in the liquid aqueous stain remover include alkoxylated alcohols, in particular primary alcohols having by preference 8 to 18 carbon atoms and an average of 1 to 15 mols of propylene oxide or of a mixture of propylene oxide (PO) and ethylene oxide (EO). Block copolymers consisting of alternating blocks of polyoxyalkylenes, especially of polyoxyethylene and polyoxypropylene blocks, can also be used, as can alkoxylated fatty acid alkyl esters.

[0026] Anionic surfactants that can be used in the liquid aqueous stain remover are, for example, those of the sulfonate and sulfate types. Surfactants of the sulfonate type are, by preference, C_9-13 alkylbenzenesulfonates, olefinsulfonates, i.e. mixtures of alkene- and hydroxyalkanesulfonates, and disulfonates, for example such as those obtained from C_12-18 monoolefins having an end-located or internal double bond, by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acid hydrolysis of the sulfonation products. Also suitable are alkanesulfonates that are obtained from C_12-18 alkanes, for example by sulfochlorination or sulfoxidation with subsequent hydrolysis and neutralization. The esters of α-sulfo fatty acids (estersulfonates), e.g. the α-sulfonated methyl esters of hydrogenated coconut, palm kernel, or tallow fatty acids, are likewise suitable.

[0027] Further suitable anionic surfactants are sulfonated fatty acid glycerol esters. "Fatty acid glycerol esters" are to be understood as the mono-, di- and triesters, and mixtures thereof, that are obtained during the production by esterification of a monoglycerol with 1 to 3 mol fatty acid, or upon transesterification of triglycerides with 0.3 to 2 mol glycerol. Preferred sulfonated fatty acid glycerol esters are the sulfonation products of saturated fatty acids having 6 to 22 carbon atoms, for example hexanoic acid, octanoic acid, decanoic acid, myristic acid, lauric acid, palmitic acid, stearic acid, or behenic acid.

[0028] Preferred alk(en)yl sulfates are the alkali, and in particular sodium, salts of the sulfuric acid semi-esters of the C₁₂-C₁₈ fatty alcohols, for example from coconut fatty alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl, or stearyl alcohol, or of the C₁₀-C₂₀ oxo alcohols, and those semi-esters of secondary alcohols of those chain lengths.

[0029] The sulfuric acid monoesters of straight-chain or branched C_7-21 alcohols ethoxylated with 1 to 6 mol ethylene oxide, such as 2-methyl-branched C_9-11 alcohols having an average of 3.5 mol ethylene oxide (EO) or C_12-18 fatty alcohols having 1 to 4 EO, are also suitable.

[0030] Additional suitable anionic surfactants are also the salts of alkylsulfosuccinic acid, which are also referred to as sulfosuccinates or as sulfosuccinic acid esters and represent the monoesters and/or diesters of sulfosuccinic acid with alcohols, by preference fatty alcohols and in particular ethoxylated fatty alcohols. Preferred sulfosuccinates contain C₈ to C₁₈ fatty alcohol residues or mixtures thereof.

[0031] Soaps, especially the sodium or potassium salts of C₁₂ to C₁₈ fatty acids, are further suitable anionic surfactants.

[0032] Betaines or alkylamidoalkylamines are, for example, suitable as amphoteric surfactants. Suitable betaines are the alkyl betaines, alkylamidobetaines, imidazolinium betaines, sulfobetaines (INCI sultaines), and the phosphobetaines, and preferably conform to the formula (R^A)(R^B)(R^C)N⁺CH₂COO^- in which R^A denotes an alkyl residue, if applicable interrupted by heteroatoms or heteroatom groups, having 8 to 25, by preference 10 to 21 carbon atoms, and R^B and R^C denote similar or different alkyl residues having 1 to 3 carbon atoms, in particular C₁₀ to C₁₈ alkyldimethylcarboxymethyl betaines and C₁₁ to C₁₇ alkylamidopropyldimethylcarboxymethyl betaines, or to the formula R^I-[CO-X-(CH₂)_n]_x-N⁺(R^II)(R^III)-(CH₂)_m-[CH(OH)-CH₂]_y-Y^- in which

R^I

is a saturated or unsaturated C_6-22 alkyl residue, preferably C_8-18 alkyl residue, in particular a saturated C_10-16 alkyl residue, for example a saturated C_12-14 alkyl residue,

X

is NH, NR^IV having the C_1-4 alkyl residue R^IV, O, or S,

n

is a number from 1 to 10, by preference 2 to 5, in particular 3,

x

is 0 or 1, by preference 1,

R^II, R^III

are, independently of one another, a C_1-4 alkyl residue, optionally hydroxy-substituted, for example a hydroxyethyl residue, but in particular a methyl residue,

m

is a number from 1 to 4, in particular 1, 2, or 3,

y

is 0 or 1, and

Y

is COO, SO₃, OPO(OR^V)O or P(O)OR^V)O, R^V being a hydrogen atom H or a C_1-4 alkyl residue.

[0033] The alkylamidoalkylamines are amphoteric surfactants of the formula R^VI-CO-NR^VII-(CH₂)_i-N(R^VIII)-(CH₂CH₂O)_j-(CH₂)_k-[CH(OH)]_l-CH₂-Z-OM in which

R^VI

is a saturated or unsaturated C_6-22 alkyl residue, preferably a C_8-18 alkyl residue, in particular a saturated C_10-16 alkyl residue, for example a saturated C_12-14 alkyl residue,

R^VII

is a hydrogen atom H or a C_1-4 alkyl residue, preferably H,

i

is a number from 1 to 10, preferably 2 to 5, in particular 2 or 3,

R^VIII

is a hydrogen atom H or CH₂COOM (see below for M),

j

is a number from 1 to 4, preferably 1 or 2, in particular 1,

k

is a number from 0 to 4, preferably 0 or 1,

l

is 0 or 1, such that k = 1 when l = 1,

Z

is CO, SO₂, OPO(OR¹²), or P(O)(OR¹²), where R¹² is a C_1-4 alkyl residue or M (see below), and

M

is a hydrogen, an alkali metal, an alkaline-earth metal, or a protonated alkanolamine, e.g. a protonated mono-, di-, or triethanolamine.

[0034] Cationic surfactants that may be employed in the liquid aqueous stain remover are preferably selected from esterquats and/or quaternary ammonium compounds (QACs) of the general formula (R^I)(R^II)(R^III)(R^IV)N⁺ X^-, in which R^I to R^IV are identical or different C_1-22 alkyl groups, C_7-28 aryl groups or heterocyclic groups, wherein two or, in the case of an aromatic incorporation as in pyridine, even three groups form a heterocycle together with the nitrogen atom, for example a pyridinium or imidazolinium compound, and X^- denotes halide ions, sulfate ions, hydroxide ions or similar anions. QACs can be prepared by reacting tertiary amines with alkylating agents, such as methyl chloride, benzyl chloride, dimethyl sulfate, dodecyl bromide, but also ethylene oxide. The alkylation of tertiary amines having one long alkyl group and two methyl groups is particularly easy, and the quaternization of tertiary amines having two long groups and one methyl group can also be carried out with the aid of methyl chloride under mild conditions. Amines which have three long alkyl groups or hydroxy-substituted alkyl groups lack reactivity and are, for example, quaternized with dimethyl sulfate. Suitable QACs are, for example, benzalkonium chloride (N-alkyl N,N-dimethyl benzyl ammonium chloride), benzalkone B (m,p-dichloro benzyl dimethyl-C12-alkyl ammonium chloride, benzoxonium chloride (benzyl-dodecyl-bis-(2-hydroxyethyl) ammonium chloride), cetrimonium bromide (N-hexadecyl-N,N-trimethyl ammonium bromide), benzetonium chloride (N,N-dimethyl-N[2-[2-[p-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy]ethyl]benzyl ammonium chloride), dialkyldimethylammonium chlorides, such as di-n-decyldimethylammonium chloride, didecyldimethylammonium bromide, dioctyldimethylammonium chloride, 1-cetylpyridinium chloride, and thiazoline iodide, as well as mixtures thereof. Preferred QACs are the benzalkonium chlorides having C8-22 alkyl residues, in particular C12-C14 alkylbenzyldimethylammonium chloride. Preferred esterquats are methyl-N-(2-hydroxyethyl)-N,N-di(tallow-acyl-oxyethyl)ammonium methosulfate, bis(palmitoyl)ethyl hydroxyethyl methylammonium methosulfate or methyl-N,N-bis(acyloxyethyl)-N-(2-hydroxyethyl)ammonium methosulfate. Commercially available examples are methyl hydroxyalkyl dialkoyloxyalkylammonium methosulfates commercially available from Stepan under the trademark Stepantex® or the products from BASF SE known by the trade name Dehyquart® or the products from Evonik Industries AG known by the trade name Rewoquat®.

[0035] In a preferred embodiment, however, the liquid aqueous stain remover is free of additional surfactants.

[0036] In a preferred embodiment, the total amount of surfactant is between 1% by weight and 10% by weight, preferably between 2% by weight and 8% by weight, more preferably between 3% by weight and 5% by weight, given as the amount of active substance and based on the total weight of the composition.

[0037] The liquid aqueous stain remover may also comprise one or more builders. Included among the builders are, in particular, carbonates, organic cobuilders, and silicates. Preferred among the carbonates are alkali metal carbonates, especially sodium carbonate. Organic cobuilders that may be mentioned in particular are polycarboxylates/polycarboxylic acids, polymeric carboxylates, aspartic acid, polyacetals and dextrins. In a preferred embodiment, however, the liquid aqueous stain remover is free of builders.

[0038] The liquid aqueous stain remover may also comprise one or more nonaqueous solvents. These organic solvents derive, for example, from the groups of the monoalcohols, diols, triols or polyols, the ethers, esters, and/or amides. Organic solvents that are water-soluble are particularly preferred in this context, "water-soluble" solvents for purposes of the present application being solvents that are completely miscible with water, i.e. with no miscibility gap, at room temperature.

[0039] Further ingredients that may be included in the liquid aqueous stain remover comprise electrolytes, fragrances, antiredeposition agents, thickeners, antimicrobial substances, germicides, fungicides, antioxidants, preservatives, corrosion inhibitors and bitter agents.

[0040] The liquid aqueous stain remover is of particular use in the removal of oily or greasy stains from textiles. It may also be used as a pre-wash stain remover. It can be preferable to spray the liquid aqueous stain remover directly onto the soiled fabric, especially when it is used as a pre-wash stain remover, so that the liquid aqueous stain remover is advantageously provided in the form of a product comprising the stain remover and a spray dispenser.

[0041] A particular embodiment therefore is a product consisting of the liquid aqueous stain remover and a spray dispenser. The spray dispenser may be of any type that can typically be used for detergent compositions, including, for example, trigger bottles or aerosol cans.

[0042] A preferred way of using the liquid aqueous stain remover to remove oily or greasy stains from textiles is by bringing the stained fabric into contact with the stain remover, allowing it to stand for a short time, eg. 2 to 10 minutes, preferably 5 minutes, and then washing the fabric. The liquid aqueous stain remover is advantageously sprayed onto the fabric, but other ways of dispensing it such as pouring it onto the stain from a bottle or pouring it onto a sponge, brush or similar implement and contacting the implement with the stained fabric, either dabbing the stain remover on or rubbing it in, are also possible. The washing process preferably takes place in a washing machine, preferably at cold temperatures, in particular at 20°C.

[0043] A particular embodiment therefore is a method of removing oily or greasy stains from items of clothing or other textiles comprising the following steps:

a) Bringing the stained fabric in contact with a liquid aqueous stain remover according to any one of claims 1 to 9, preferably by spraying the stain remover onto the fabric,

b) Waiting for 2 to 10 minutes, preferably for 5 minutes,

c) Washing the fabric, preferably in a washing machine and preferably at 20°C.

[0044] The method may also comprise additional steps, such as dabbing or rubbing the stain remover into the stained fabric.

[0045] A liquid aqueous stain remover having the following composition was prepared:

Water	92.15
HEDP (60%)	0.5
Monoethanolamine	1.0
Amine oxide (30%)	3.0
Laureth-7	3.0
Acticide	0.1
Perfume	0.25

(All amounts given in wt.-% of the raw material; where less than 100%, the percentage of active material in the raw material is also given.)

[0046] This composition showed an improved performance over several greasy or oily stains while maintaining the colour of the fabrics. Further tests also showed that no fabric damage could be observed after 10 application/wash cycles despite the alkalinity of the formula.

Claims

1. Liquid aqueous stain remover for use on textiles comprising at least one amine oxide and at least one fatty alcohol ethoxylate, characterized in that it additionally comprises 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and has a pH value of 9.5 to 10.5.

2. Liquid aqueous stain remover according to claim 1, characterized in that the at least one fatty alcohol ethoxylate is a C8-20, preferably C10-16, more preferably C12-14 fatty alcohol ethoxylated with 2-20 moles of EO, preferably 4-15 EO, more preferably 6-10 EO.

3. Liquid aqueous stain remover according to claim 1 or 2, characterized in that the fatty alcohol ethoxylate is lauryl alcohol ethoxylate with 7 EO (laureth-7).

4. Liquid aqueous stain remover according to any one of the preceding claims, characterized in that the at least one amine oxide is present in the liquid aqueous stain remover in an amount of 0.1% by weight to 5% by weight, preferably 0.5% by weight to 4% by weight, more preferably 0.8% by weight to 2% by weight, for example 1% by weight, given as the amount of active substance and based on the total weight of the composition.

5. Liquid aqueous stain remover according to any one of the preceding claims, characterized in that the at least one fatty alcohol ethoxylate is present in the liquid aqueous stain remover in an amount of 0.5 % by weight to 8% by weight, preferably 1% by weight to 6% by weight, more preferably 2% by weight to 4% by weight, for example 3% by weight, given as the amount of active substance and based on the total weight of the composition.

6. Liquid aqueous stain remover according to any one of the preceding claims, characterized in that the total amount of surfactant is between 1% by weight and 10% by weight, preferably between 2% by weight and 8% by weight, more preferably between 3% by weight and 5% by weight, given as the amount of active substance and based on the total weight of the composition.

7. Liquid aqueous stain remover according to any one of the preceding claims, characterized in that it contains monoethanol amine as a pH regulator.

8. Liquid aqueous stain remover according to claim 7, characterized in that it contains monoethanol amine in an amount of at least 1 wt.-%, relative to the total weight of the composition.

9. Liquid aqueous stain remover according to any one of the preceding claims, characterized in that it further comprises ingredients selected from the group comprising other surfactants, builders, nonaqueous solvents, electrolytes, pH adjusting agents, fragrances, thickening agents, antiredeposition agents, antimicrobial substances, germicides, fungicides, antioxidants, preservatives, corrosion inhibitors and bitter agents.

10. Use of a liquid aqueous stain remover according to any one of the preceding claims for the removal of oily or greasy stains from textiles.

11. Use according to claim 10, characterized in that the liquid aqueous stain remover is used in cold wash conditions, preferably at 20°C.

12. Product consisting of a liquid aqueous stain remover for use on textiles according to any one of claims 1 to 9 and a spray dispenser.

13. Use of the liquid aqueous stain remover according to any one of claims 1 to 9 as a pre-wash stain remover, preferably in the form of a product according to claim 12.

14. Method of removing oily or greasy stains from items of clothing or other textiles comprising the following steps:

d) Bringing the stained fabric in contact with a liquid aqueous stain remover according to any one of claims 1 to 9, preferably by spraying the stain remover onto the fabric,

e) Waiting for 2 to 10 minutes, preferably for 5 minutes,

f) Washing the fabric, preferably in a washing machine and preferably at 20°C.