SK81199A3 - Aqueous cleaning composition for hard surfaces and hard surfaces cleaning method - Google Patents

Abstract

The specification disloses improved compositions which both clean a surface and are believed to deposit thereupon a layer of cationic surfactant which assists the release of soil subsequently deposited upon said surface. These comprise a surfactant mixture, wherein said surfactant mixture itself comprises: a) at least 65 wt.% on total surfactant of nonionic surfactant; b) less than 1 wt.% on total surfactant of anionic surfactant; c) 0.1-35 wt.% on total surfactant of a cationic surfactant which is a mono fatty alkyl quaternary ammonium compound wherein the alkyl chains comprise at least 10 % of C18-C26 alkyl groups; wherein said composition further comprises, at least 0.5 wt.% of an organic amine having a pKa of at least 8.0.

Description

Aqueous hard surface cleaner and method for cleaning hard surfaces

Technical field

The present invention relates to an alkaline hard surface cleaner comprising an aliphatic alkyl cationic surfactant and a nonionic surfactant.

BACKGROUND OF THE INVENTION

For routine cleaning of hard surfaces such as wood, glazed tiles, colored metals, etc. it is known that after removal of the soil by means of a surfactant or solvent-containing composition, lacquers, waxes or polishing agents are used as a separate step to preserve and protect the surface and delay the re-settling of the soil. Such step-by-step cleaning and preservation is time-consuming and complex.

It has been proposed to incorporate soil release agents, including polymers, siloxanes and dialkyl quaternary cationic surfactants, into detergent compositions, which has a secondary cleaning benefit. It is contemplated that these soil removal agents act by forming a layer of polymer, siloxane, or surfactant on the surface during cleaning. This layer should then facilitate further cleaning by reducing the degree of adhesion of the dirt to the surface.

It is preferred that these compositions be strongly alkaline in order to contribute to the purification. Of these, the quaternary, cationic surfactants are the cheapest. Such quaternary salts typically contain quaternized nitrogen with one or two additional fatty acid chains and three or two additional lower aliphatic alkyl chains. Compositions containing dialkyl quaternary cationic surfactants have been found to be difficult to stabilize against flocculation or phase separation due to interactions of the components present.

Consequently, there is a technical problem in terms of stability with strongly alkaline cleaning compositions containing an effective amount of a quaternary nitrogen containing an impurity releasing agent.

Stable formulations containing an alkaline organic amine are proposed which clean the surface and deposit on it a layer of a cationic surfactant with a relatively long mono-aliphatic alkyl chain which releases an impurity subsequently deposited on said surface. The stability of such formulations is reported to result from the combination of an alkaline organic amine and a monoaliphatic alkyl cationic surfactant.

SUMMARY OF THE INVENTION

The present invention provides an aqueous hard surface cleaning composition comprising a mixture of surfactants consisting of:

(a) at least 65% by weight of the non-ionic surfactant on the total surfactant;

b) less than 1% by weight of the anionic surfactant based on the total amount of surfactant;

c) 0.1 to 0.35% by weight of a cationic surfactant based on the total amount of the surfactant, which is a monoaliphatic alkyl quaternary ammonium compound, wherein the alkyl chains contain at least 10% of C18 to C26 alkyl groups;

wherein the composition further comprises at least 0.5% by weight of organic amine having a _pKa of at least 8.0.

It is recognized that the cationic surfactants present in the compositions of the present invention modify the surface energy on the surfaces to which they are applied to increase the wetting angle of the impurity subsequently deposited on the modified surface.

For further understanding, the invention will be described in more detail below, with particular reference to the preferred ingredients and details of the compositions.

-3Cationic surfactants

A number of cationic mono-aliphatic alkyl quaternary ammonium compounds find suitable use in the compositions of the present invention. Particularly suitable cationic surfactants have the general formula:

[R ¹ R ² R ³ R ⁴ N] ⁺ X 'wherein R ¹ , R ² and R ³ are independently C 1-4 alkyl, R ⁴ is an aliphatic alkyl chain and X is a monovalent anionic equivalent and the chain length distribution in the substance is such that wherein at least 10% by weight of the substance the aliphatic alkyl chain contains C18 to C26 carbon atoms. It is preferred that less than 60% by weight of the substance comprises mono-aliphatic alkyl quaternary ammonium compounds in which the aliphatic alkyl chain is C16 or less.

It is acknowledged that these longer chain aliphatic alkyl quaternary compounds have better efficacy in terms of secondary purification than shorter monoaliphatic alkyl chain compounds. It has also been found that the use of substances with a monoaliphatic alkyl chain is more suitable for manufacture than the use of the corresponding substance with a dialkyl aliphatic chain. A halide, especially chloride or bromide, is a suitable counterion.

The aliphatic alkyl chain can be derived from synthetic or natural raw materials. If the aliphatic alkyl chain is derived from natural raw materials, it usually contains a mixture of substances with different alkyl chain lengths in the aliphatic alkyl chain. It is preferred that the aliphatic alkyl chains be fully saturated. It appears that saturated alkyl chains will have effective properties due to the adhesion of alkyl chains to surfaces and interfaces.

Preferably, the cationic surfactant comprises a cation of the formula wherein R ¹ = R ² = R ³ = CH 3. Substances of this basic nature in which the lower alkyl groups are methyl groups are commercially available.

A particularly preferred compound is trimethylbehenylammonium bromide. It has been found that this material will flocculate over time in the presence of significant amounts of inorganic salts, including alkali such as e.g. sodium hydroxide and sodium carbonate or potassium carbonate. As described below, this problem can be avoided in the compositions of the present invention.

-4Nonionic surfactants

The compositions of the present invention comprise a nonionic surfactant. The presence of a nonionic surfactant has been shown to contribute significantly to the cleaning performance of the compositions of the invention.

Suitable nonionic detergents can be roughly characterized as compounds produced by condensation of alkylene oxide groups that are hydrophilic in nature with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature.

The length of the hydrophilic or polyoxyalkylene radical which is condensed with any particularly hydrophobic group can be adjusted to provide a water-soluble compound with the desired degree of equilibrium between the hydrophilic and hydrophobic components.

Particular examples include the condensation product of aliphatic alcohols having 6 to 22 carbon atoms in a linear or branched chain with ethylene oxide, such as, for example, a condensate of coconut oil with ethylene oxide with 2 to 15 moles of ethylene oxide in 1 mole of coconut alcohol; condensates of alkylphenols having an alkyl group of 6 to 12 carbon atoms with 5 to 25 moles of ethylene oxide per mole of alkyl phenol; condensates of the reaction product of ethylenediamine and propylene oxide with ethylene oxide, condensates containing from 40 to 80% by weight of polyoxyethylene radicals, with a molecular weight of from 5,000 to 11,000; tertiary amine oxides of the structure R 3 NO, wherein one R group is an alkyl group of 8 to 18 carbon atoms and the others are each methyl, ethyl or hydroxyethyl, e.g. dimethyldodecylamine; tertiary phosphine oxides of the structure R 3 PO, wherein one R group is an alkyl group having 10 to 18 carbon atoms and the others are each an alkyl or hydroxyalkyl group having 1 to 3 carbon atoms, e.g. dimethyldodecylphosphine; and dialkyl sulphoxides structure R ² SO where the group R is an alkyl group having 10 to 18 carbon atoms and the other is methyl or ethyl, e.g. methyltetradecyl sulphoxide; aliphatic acid alkylolamides; condensates of alkylene oxide with alkylolamides of aliphatic acids and with alkyl mercaptans.

The most preferred nonionic surfactants are ethoxylated alcohols having 6 to 14 carbon atoms and 2 to 9 moles of ethoxylation. Suitable substances include IMBENTIN 91/35 OFA (TM) Cg-n nonionic compound having an average of

-55 moles of ethoxylation and NONIDET 91-6T (TM) distilled Cg.n nonionic compound with an average of 6 moles of ethoxylation.

Many other nonionic surfactants are known to those skilled in the art, as reported by M. J. Schick Nonionic surfactants, Marcel Dekker (1967) and subsequent editions of the same work.

The amount of nonionic active detergent to be used in the composition of the invention will generally range from 1 to 30% by weight, more preferably from 2 to 20% by weight, and most preferably from 5 to 10% by weight.

It is particularly preferred that the ratio of nonionic surfactant to anionic and cationic surfactant is such that > 75% of the total surfactant present in the formulation is a nonionic compound.

It is important that the compositions of the present invention contain only low levels of active anionic detergents or are absent for practical reasons. The presence of anionic detergents has been reported to cause complex formation between cationic and anionic detergents, thereby reducing the effectiveness of the formulations.

The total surfactant content of the compositions of the invention will generally be in the range of 1 to 30% by weight.

Organic amines

In essence, the compositions of the invention contain at least 0.5% by weight of an organic amine, with a pK _and at least 8.0. This component is considered to be an ester cleavage agent and serves to purify refractory impurities such as e.g. pyrolized impurities that arise when fatty and / or protein foods are heated on the surface. When organic amines with a lower pK _a , such as e.g. aniline, in terms of cleaning ability are ineffective. If inorganic alkalis are present at significant levels, the above-mentioned quaternary substance flocculates and the phase separates.

It is preferred that the composition contains from 1 to 10% by weight of alkanolamine, particularly preferably levels of 2 to 6% by weight. Particularly suitable alkanol

-6-amines include: 2-amino-2-methyl-1-propanol, monoethanolamine and diethanolamine. The most preferred organic amine is 2-amino-2-methyl-1-propanol.

The compositions of the present invention preferably contain salts of electrolytes in an amount of less than 1%, including sodium carbonate and / or potassium carbonate, bicarbonates and / or hydroxides.

Minority and other ingredients

Some minor components may be present in the compositions of the invention. The composition of the invention may contain other ingredients which improve the cleansing performance and / or improve the physical properties of the composition. These components are not essential to the practice of the invention.

Hydrophobic oils are optional ingredients of the compositions of the present invention. Suitable oils include oils that rapidly dissolve triglycerides. In the presence of oils, preferred oils are limonene, para-cymene, di-butyl ether and butyl butyrate.

A further optional component of the compositions of the present invention is a soap suds controlling agent that can be used in the compositions of the present invention when such compositions tend to produce an increased amount of foam. Examples of soap suds control agents are organic solvents, hydrophobic silicon, and silicone oils or hydrocarbons.

Solvents are optional components of the formulations of the invention. When solvents are used, those having the formula R ¹ -O- (EO) _m - (PO) _n -R ² are preferred, wherein R ¹ and R ² are independently C 2 -C 6 alkyl or H, but are not both hydrogen, m and n are independently 0 to 5. More preferably, the solvent is selected from the group consisting of diethylene glycol mono-n-butyl ether, mono-ethylene glycol, mono-n-butyl ether, propylene glycol n-butyl ether, isopropanol, ethanol, butanol, and mixtures thereof. Alternative solvents are pyrrolidinone, e.g. N-methylpyrrolidinone.

It has been found that the use of a long chain aliphatic alcohol, preferably C16 or longer, more preferably C16 to C20, such as e.g. industrial alcohol, improve cleaning performance. Typically, these alcohols are present in an amount of 0.001 to 2% and more preferably less than 1%.

The compositions according to the invention may contain, in addition to the aforementioned components, various other ingredients already mentioned, such as pH regulators, colorants, optical brighteners, dirt-settling agents, detergent enzyme-compatible bleaching agents, gel-regulating agents, antifreeze stabilizers, bactericidal agents , preservatives, hydrotropic detergents, fragrances and opacifiers.

It has been found appropriate to supply the products of the invention in the form of relatively small batches of the product in relatively fine form of dispersed droplets. This is a significant advantage since only small batches of the product need to be used. Preferably, the formulations of the invention are packaged in containers adapted to form a spray of 0.1 to 1.5 ml of product per spray, the droplet size of said spray being in the range of 30 to 300 μητ

It has been found to be particularly advantageous to use the polymer as a component of the compositions of the invention, since it reduces the degree of formation of exceptionally tiny droplets when sprayed in the form of a relatively fine mist. Suitable polymers are polyvinylpyrrolidone, commercially available as PVP k-90 polymer.

Suitable levels of PVP polymer are upwards of 50 ppm. Levels of 300 to 2000 ppm are particularly preferred.

A particularly preferred pH of the formulations is > 10, and these formulations mixed with water comprise:

a) 3 to 15% nonionic surfactant (preferably, C9 to C12 EO5-8 nonionic surfactant)

b) 2 to 10% solvent (preferably, diethylene glycol mono-n-butyl ether)

c) 2 to 6% alkanolamine (preferably, 2-amino-2-methyl-1-propanol)

d) 0 to 2000 ppm of polymer (preferably, PVP); and

e) 0.1 to 4% of a cationic surfactant comprises a cation of the general formula [R ¹ R ² R ³ R ⁴ N] ⁺ X wherein R ¹ , R ² and R ³ are independently C 1-6. ₆ alkyl, R ⁴ is a fatty alkyl chain comprising at least 10% C18 to C26 carbon atoms and X is an monovalent anion equivalent.

For a better understanding, the present invention is further described in the form of a non-limiting example.

-8Examples of embodiments of the invention

Aqueous preparations containing a nonionic surfactant and a relatively low level of cationic surfactant were produced as shown in Table 1 below using the following substances (all preparations are in% by weight unless otherwise indicated):

NONLNONIDET 91-6T (TM: ex. Nippon Shell): C9 to C11 ethoxylated alcohol with 6 moles of ethoxylation and distilled to reduce the amount of low ethoxylates.

VEM: Behenyltrimethylammonium chloride (ex Nippon Oils & Fats)

DIGOL: Butyl Digol (TM): diethylene glycol mono-n-butyl ether,

AMP: 2-amino-2-methyl-1-propanol

CTAB: Cetyltrimethylammonium bromide (ex: BDH)

DEA: Diethanolamine

CARB: potassium carbonate

POL: PVP K-90 (TM ex. International Specialty Polymers)

2HT: NISSAN CATION 2ABTN (TM ex: Nippon Oils & Fats): di-reinforced dimethyl ammonium chloride.

Table 1

Examples 1-5 Example 1 2 3 4 5 NONI 10% 10% 10% 10% 10% DIGOL 8% 8% 8% 8% 8% AMP 4% 4% 4% 4% 4% CARB - - - - 1,25% VBM 0 1 0 0 1 CTAB 0 0 0 1 0 2HT 0 0 1 0 0 ETH 1097 560 634 735 - stability Yes Yes not Yes not

All samples contained 0.1% polyvinylpyrrolidone, commercially available as PVP k-90 (TM) polymer, and 0.2% fragrance.

For Example 1, the required amounts of all components were mixed at room temperature. For examples 2 & 5, VBM was added to hot water at 80 ° C and the mixture was stirred in a Heidolph mixer at 80 ° C for 2 hours to obtain a solution at a concentration of 15.5% by weight. The desired amount of this solution (still at 80 ° C) was then added to the desired amount of the solution containing all the remaining ingredients at room temperature and the solution was stirred for an additional 10 min. For Example 3, equal amounts of nonionic surfactant (NONI) and hardened technical dimethylammonium chloride were mixed at 60 ° C. The desired amount thus obtained was added (still at 60 ° C) to the desired amount of the solution containing all the remaining ingredients at room temperature and the solution was stirred for an additional 30 min. For Example 4, all required amounts of all components were mixed at room temperature. The solution was then briefly heated to 60 ° C for homogenization.

For the purpose of measuring the purification results, the following tests were performed. 100 g of 1.5 poise dehydrated castor oil (ex. SEATONS) were weighed into a glass container. To this was added 0.2 g of FAT RED (TM) dye (ex. SIGMA) and the mixture was vigorously stirred (2000 RPM) for 6 hours using a Heidolph mixer. If not used, it was frozen. Porcelain glazed tiles (380 x 300 mm) were cleaned using a freshly dampened cloth J-CLOTH (TM) followed by JIF cream (TM), then a commercially available high quality hand dishwashing liquid and finally calcite powder. After drying, residual calcite was removed by polishing with a paper towel.

ml of the formulations listed in Table 1 were applied to cleaned tiles using a freshly moistened J-CLOTH cloth. The tiles were rinsed with tap water for 15 seconds to remove excess product and allowed to dry. The tiles were contaminated on a 215 x 150 mm surface with a gravity-filled gun (MODEL MPS-514/515) using compressed air at 172 psi (25 psi), spraying for 35 seconds from a distance of 27 cm. The contaminated tiles were placed horizontally on an oven at 85 ° C and allowed to stand at this temperature for 1.5 h and then left to stand overnight.

- 10Tiles were cleaned by hand with moist J-wipes and preparations listed in Table 1. The effort required to clean the tiles was labeled Eth in Table 1. Eth measurements are expressed in Newtonseconds, higher values indicate that more effort was required to clean the tiles .

Stability was determined by placing the samples at 5, 25 and 37 ° C for 3 months. In cases marked as unstable in Tab. 1, a cloudy precipitate is formed under one or more storage conditions.

From the results in Tab. 1 shows that the lowest purification effort score was obtained with Example 2, which is the subject of the invention using a quaternary cationic compound with a longer aliphatic alkyl chain VBM. Examples 3 and 4 also showed an improvement over the control formulation designated as Example 1. It can be seen that this improvement was or slightly as with the shorter alkyl chain (CTAB: as used in Example 4) or the storage stability was lost as in the dialiphatic alkyl (2HT: as used in Example 3). Example 5 shows that the combination of an alkali salt with VBM did not result in a stable product.

Further results are shown in Tab. 2 below. The same raw materials were used as described above. Eth is as described above. Sample 11 was made as Sample 1. Samples 6, 7, 9 and 10 were made as Sample 2 and 5. Sample 8 was made as Sample 3.

WIRA is% dirt removal using the Wool Industries Research Association Abrasion Tester. To obtain these results, 10 cm x 10 cm steel tiles were cleaned using calcite followed by rinsing with deionized water. 25 g salad oil (ex Nisshin, Japan), 5 g plain flour (Homepride [RTM], ex Dalgety, UK), 75 g acetone were mixed together for 2 minutes using a Silverson [RTM] high speed mixer. This mixture was then sprayed using a Humbrol paint sprayer [RTM] on cleaned tiles, a circular overlap to obtain a stain of 5.5 cm diameter. The acetone was allowed to evaporate to give 0.04-0.05 g of impurity per tile. Contaminated tiles were heated to 175 ° C for 34 minutes and allowed to stand overnight before cleaning. The contaminated tile was placed in a WIRA tester and 0.5 ml of test substance was applied. Then the tile was cleaned using Jcloth [RTM] (ex. Johnson and Jphnson, UK) stacked on 8 layers at

- 11 hydraulic pressure of 657 g / cm ³ , in one complete cycle (17 piston depressions). This procedure was repeated to obtain three complete cycles, using a freshly moistened J-cloth and 0.5 ml of test product at each step. After all three cycles, the soiled tiles were removed, rinsed and allowed to dry at 50 ° C for 30 minutes. The total weight of contaminant removed was then calculated and expressed as a percentage of the original weight of the contaminant. This is referred to as WIRAvtab. Second

CB is the contact angle on the glass that comes into contact with the composition of the example using brominaphthalene.

Table 2

Examples 6-11 Example 6 7 8 9 10 11 NONI 10% 10% 10% 10% 10% 10% DIGOL 8% 8% 8% 8% 8% 8% AMP 4% - 4% - 4% 4% DEA - 4% - - - - CARB - - - - 1,25% 1,25% VBM 1 1 0 1 1 0 CTAB 0 0 1 0 0 0 ETH 185 474 1383 336 742 2919 WIRA 88 84 83 57 85 89 CB 27 31.8 23.6 29 30 20.1

Examples 6, 7 and 10 are in accordance with the invention, the other examples being comparative. Example 11 represents a commercially successful kitchen cleaner.

From tab. It can be seen that greater purification effort (CETh) is required when no quaternary cationic compound is used in the formulation (Example 11) or when the quaternary cationic substance has a short chain (Example 8).

The 12WIRA results, for which better scores represent a higher score, show that the presence of organic amines AMP (Examples 6 and 10) yields a more efficient formulation than when the amine is not present (Example 9).

The CB data demonstrate that the formulations of the invention modify the surface energy (which can be calculated from the contact angle) compared to the known kitchen cleanser (Example 11), which contains no quaternary cationic substance. The surface energy modification is less for CTAB-based formulations (Example 8).

In general, it can be seen that Examples 6 and 7 clean the surface with reduced effort and leave the surface energy modified, which prevents or reduces the possibility of recontamination. Example 8 is less effective, especially with respect to thermally obsolete impurities. The formulation of Example 9 will act on such impurities used in the Eth determination, but as a general cleaning agent it is weak. Example 10 is acceptable, but it is preferred that the carbonate is absent.

Claims (10)

PATENT CLAIMS An aqueous hard surface cleaning composition comprising a surfactant mixture comprising: (a) at least 65% by weight of the non-ionic surfactant on the total surfactant; (b) less than 1% by weight of the anionic surfactant based on the total amount of surfactant; c) 0.1 to 0.35% by weight of a cationic surfactant which is a monoaliphatic alkyl quaternary ammonium compound, wherein the alkyl chain comprises at least 10% of C18 to C26 alkyl groups; wherein the cleaning composition further comprises at least 0.5% by weight of organic amine having a _pKa of at least 8.0. The aqueous cleaning composition of claim 1, wherein the mono-aliphatic alkyl quaternary ammonium compound has the general formula: [R ¹ R ² R ³ R ⁴ N] ⁺ X wherein R ¹ , R ² and R ³ are independently C 1-4 alkyl, R ⁴ is an aliphatic alkyl chain and X is a monovalent anionic equivalent, wherein the chain length distribution in the substance is such that less than 60% by weight of the composition comprises mono-aliphatic alkyl quaternary ammonium compounds in which the aliphatic alkyl chain is C16 or less. 3. Composition according to claim 2, characterized in that R ¹ = R ² = R ³ = CH _third The aqueous cleaning composition of any one of claims 1 to 3, wherein the mono-aliphatic quaternary ammonium compound is a trimethylbehenylammonium halide. Aqueous cleaning composition according to claim 1, wherein the ratio of nonionic surfactant to anionic and cationic surfactant is such that more than 75% of the total surfactant in the composition is a nonionic surfactant. Aqueous cleaning composition according to claim 1, characterized in that it contains 2 to 10% of an organic amine. Aqueous cleaning composition according to claim 1, wherein the organic amine is selected from the group consisting of 2-amino-2-methyl-1-propanol, mono-ethanolamine and di-ethanolamine. Aqueous cleaning composition according to claim 1, characterized in that it is packaged in a spray adapted container for a single spray of 0.1 to 1.5 ml of the composition, with an average droplet size per spray between 30 and 300 µm. 9. The aqueous cleaning composition of claim 1 having a pH of greater than 10 and, with the addition of water, comprising: (a) 3 to 15% nonionic surfactant b) 2 to 10% solvent c) 2 to 6% organic amine d) 0 to 2000 ppm of a polymer; and e) 0.1 to 4% of the cationic surfactant comprises a cation of the general formula [R ¹ R ² R ³ R ⁴ N] ⁺ X ', wherein R ¹ , R ² and R ³ are independently C 1-4 alkyl, R ⁴ is an aliphatic alkyl the chain containing at least 10% C18 to C26 carbon atoms and X is a monovalent anionic equivalent. A method of cleaning hard surfaces, comprising the step of cleaning the surface with an aqueous cleaning composition according to any one of claims 1 to 9, by spraying the composition onto the surface.