SK48595A3 - Aqueous cleaning mixture - Google Patents

Abstract

Ideal household cleaning compositions should form a relatively stable foam on application to a surface and rapidly de-foam when rinsed from the surface. The present invention subsists in an aqueous cleaning composition comprising: (a) a surfactant system comprising an anionic surfactant other than an alkali metal salt of a fatty acid, (b) C10-C18 monocarboxylic fatty acid, (c) a semi-polar solvent, (d) a polycarboxylic acid, and (e) a base, said composition having a pH of less than 6. It is believed that the C10-18 fatty acids have a foam boosting effect which improves 'cling' of the foam to sloping or vertical surfaces. When the compositions are diluted during rinsing the fatty acid and the solvent form an antifoam system which defoams the composition.

Description

The invention relates to improvements in cleaning compositions for general household use.

BACKGROUND OF THE INVENTION

General Purpose Household Cleaning (GPC) compositions are commercially available in both powder and liquid form.

Powder cleaning compositions consist mainly of a detergent component or buffer salts such as phosphates, carbonates, silicates, etc. Such compositions show good removal of inorganic contaminants, but may have insufficient cleaning power for organic contaminants, such as calcium and / or magnesium salts of fatty acids, and fatty / greasy contaminants typically found in the domestic environment. Such compositions generally form solutions buffered to alkaline pH by the detergent component. It is generally believed that alkaline pH facilitates the purification of free fatty acids by conversion to the corresponding soap.

Cleaning liquid compositions generally include an organic solvent and have the great advantage that they can be applied to hard surfaces in diluted or concentrated form, so that relatively high levels of surfactant and organic solvent are supplied directly for contamination. These liquid compositions are especially used in cleaning hard surfaces such as floors and walls and kitchen or bathroom surfaces, and are also useful in cleaning soft parts of equipment such as upholstery, carpeting, curtains, etc. Furthermore, these compositions are generally alkaline buffered, although neutral compositions are also known, and several acidic compositions have been marketed as special bathroom cleaners.

Both types of mixtures mentioned above may contain organic acids such as citric, adipic or glutaric acid.

Typically, the surfactants used in commercial all-purpose cleaners contain either one or both of linear alkyl benzene sulfonates (ABS) and secondary alkane sulfonates (SAS).

The incorporation of certain surfactants into such solvent / water mixtures does not present difficulties when these surfactants are present at relatively low concentrations. European patent EP 0344847 (P&G) discloses compositions comprising butoxypropanol solvents in combination with up to 5% by weight of linear C8-C18 alkylbenzenesulfonate.

Mixtures of linear alkyl benzene sulfonates with alcohol ethoxylates and optionally small amounts of fatty soaps contain surfactant systems used in many successful liquid alkaline commercial products at pH 8-11.

In addition, to remove grease / greasy contamination, it is desirable that household cleaning compositions have the ability to remove scale. The limescale mostly consists of calcium carbonate and magnesium carbonate, which are present as the corresponding bicarbonates at different levels in natural waters and form carbonates by crystallization with disproportionation. It is well known that carbonates are soluble in acidic solutions. However, for the above reasons, it is believed that acidic compositions are less effective than alkaline compositions.

Another significant technical problem with such compositions is that the most commonly used surfactants are less biodegradable and consequently less environmentally friendly than other surfactant systems.

In particular, primary alcohol sulphate (referred to herein as PAS) is an environmentally desirable anionic surfactant, both because of its easy biodegradability as compared to linear, alkylbenzenesulfonate and the fact that it can be obtained from natural materials such as coconut or other vegetable oil as a source of fatty acid residues.

Primary alcohol sulphate comprises a mixture of materials of the formula RO with ₃ X wherein R is a Cg to Cgg primary alkyl group and X is a solubilising cation. Known cations include sodium, magnesium, potassium, ammonium, TEA and mixtures thereof.

The use of PAS salts in combination with other surfactants is well known in the literature.

EP 125711 (Čarke: 1984) relates to GPC mixtures containing nonionic surfactants, anionic surfactants (examples are Mg-PAS) and partially esterified resin.

GB-2160887 (Bristol Myers: 1984) relates to GPC compositions comprising a solvent, anionic surfactants containing alkali metal, magnesium, ammonium and TEAPAS salts, and 0.005 to 3.0% by weight nonionic surfactant containing 75 to 100% a water insoluble nonionic surfactant. The most preferred anionic surfactant is sodium lauryl sulfate (Na-C 2 PAS).

GB 2144763 (P&G: 1983) relates to an acidic cleaning composition in the form of a microemulsion containing at least 5% by weight of a solvent and a magnesium salt. Preferred compositions include mixtures of nonionic surfactants, paraffin sulfonates, alkyl sulfates (PAS), ethoxylated phenols and ethoxylated alcohols.

EP 107946 (P&G: 1982) relates to liquid detergent compositions (dishwashing) containing 6 to 18% by weight Mg-PAS, together with a water-soluble C18-C18 alkane or alkene sulfonate and a water-soluble alkyl ether sulfate.

The above-mentioned surfactants ABS, SAS and PAS are very effective foaming surfactants. While foam formation is desirable for many human wash products, such as shampoos and toilet soaps, the presence of foam is often undesirable in washing, fabric and surface cleaning operations, as it may be difficult to remove the foam after the cleaning operation. Therefore, antifoam additives have been added to the formulations. Calcium soaps, i. calcium salts of fatty acids are well known as antifoams in fabric wash compositions and hard surface cleaning compositions.

The use of a combination of hydrocarbons and calcium-sensitive fatty acid soaps as antifoam systems for powder compositions has been described in GB 1099562 (Unilever: 1964). Described herein are powdered detergent compositions which include anionic sulfate or sulfonate detergents, alkali polyphosphates, and soap suppressors of a hydrocarbon and a C12-C31 fatty acid. A hydrocarbon is broadly defined as including straight chain or branched alkanes (liquid paraffin oils in a 1: 1 mixture with high melting paraffin waxes boiling above 90 ° C), alkenes, alkylated benzenes, condensed aromatics such as naphthalene and anthracene and their alkylated derivatives and alicyclic hydrocarbons, including terpenes and the like. Preferred hydrocarbons include these materials boiling above 90 ° C, such as in the aforementioned blends of paraffin oils and waxes, dodecylbenzene and turpentine oil.

The use of a combination of solvents, soaps and selected terpene solvents as antipoaming systems for liquid cleaning compositions for hard surfaces is further described in EP 0080749 (P&G: 1982). In these compositions, unlike, for example, carpet cleaning compositions, it is preferable that the product can be used arbitrarily without the step of adding a separate antifoam component.

More particularly, EP 0080749 teaches the use of mono (two isoprene units) or sesqui (three isoprene units) terpenes in combination with both the specified solvent (2 (2-butoxyethoxy) ethanol: commercially available as BUTYL CARBITOL [RTM]) as well as 0, 05 to 2% by weight of one or more alkali, ammonium and alkanolammonium soaps with C13 to C24 fatty acids as antifoam system. In this reference, the three components are interacting to have antifoam activity.

Preferred terpenes as described in this reference are mono and bicyclic terpenes having a hydrocarbon class of terpenes, such as terpinenes, terpinolenes, limonenes, pinenes, and so-called orange terpenes, which are obtained from the orange peel. Other terpenes including terpene alcohols, aldehydes and ketones are less preferred.

Terpenes and related substances suffer from the general disadvantage that they are relatively expensive raw materials and fragrant compounds and generally impart pine or lemon flavor to the products. It is desirable that the basic compositions of the cleaning compositions have a low or no odor. In addition, terpenes may contain traces of so-called musk xylenes and doubts have arisen as to the physiological acceptability of these materials.

Products intended to be used as bathroom cleaners are intended to form a relatively stable adhesive foam in the early stages of cleaning. This foam provides a visible indication of the parts of the surface to which the cleaner has been applied. More importantly, the foam adheres to the surface and prevents runoff, thereby minimizing the amount of surfactant containing the product that is desired and consequently minimizing both cost and release of surfactants to the environment. However, it is desirable, in order to facilitate use and to protect the water, that the mixture be rinsed using as little water and little effort as possible.

Taking into account all of the foregoing, it can be seen that the ideal household cleaning composition is to form a relatively stable foam when applied to the surface and to quickly stop foaming when rinsing from the surface. Such mixtures should not contain environmentally or physiologically unacceptable ingredients ει should not require the addition of special anti-foaming ingredients to the rinsing water. While special cleaning compositions that meet many of these needs in particular have already been sold or suggested in the literature, a general purpose cleaner is required which has the advantages of an acid scaler, but which is also effective against a wide range of contaminants.

SUMMARY OF THE INVENTION

BRIEF DESCRIPTION OF THE INVENTION

We have found that some fatty acids have a foam-enhancing effect at a certain concentration of formulations and a foam-suppressing effect when these formulations are diluted with slightly alkaline water. When these fatty acids are combined with polycarboxylic acids, solvents, and surfactants at an acidic pH, remarkably simple combinations of ingredients form mixtures that exhibit excellent cleaning over a wide range of contaminants and exhibit excellent rinsing behavior.

Accordingly, the present invention resides in aqueous cleaning compositions comprising:

(a) a surfactant system containing an anionic surfactant other than an alkali metal salt of a fatty acid;

(b) a C10 to C22 monocarboxylic fatty acid;

c) semipolar solvent,

(d) polycarboxylic acid or a salt thereof; and

e) a base, and the mixture has a pH of less than 6.

DETAILED DESCRIPTION OF THE INVENTION

As mentioned above, we have found that C10 to C22 fatty acids surprisingly have the effect of enhancing the foam in the compositions of the present invention. This is expressed in the improved adhesion of the foam to the inclined or vertical surfaces. Thus, the compositions of the invention are particularly well adapted for use as hard surface cleaning compositions.

Without wishing to limit the invention by reference to the theory of action, it is believed that at the pH below pK _{and of the} monocarboxylic fatty acid, the effect of foam enhancement is observed. The exact pK _and fatty acids are difficult to confirm in practice because the fatty acids are not water soluble under these conditions, although a good estimate of the pK _and can be obtained by titration. It is contemplated that the pH of the mixture should be above the lowest pK _and polycarboxylic acid such that the polycarboxylic acid exists in partially ionized form.

Household water sources generally contain some dissolved calcium, derived from minerals at typical levels of 20 to 400 ppm (2 to 40 degrees French). Waters with higher calcium levels are known, but relatively rare.

Household water sources typically have a slightly alkaline pH of about 7.5, typically about 8, and are principally caused by dissolved bicarbonates that are naturally present in water. In a few exceptional cases, the alkalinity forming components, such as calcium oxide, may be added to an aqueous source to neutralize acidic waters and thereby prevent the dissolution of lead and other potentially toxic metals from pipelines and equipment.

When a certain amount of calcium containing household alkaline water is added to the mixture of the present invention, it is believed that the alkalinity of the water increases the pH of the initially acidic system to a point above pK _{and of} fatty acid and causes fatty acid ionization. water to form calcium soap. This precipitate has an antifoam effect in a known manner and is subsequently considered to aid in rinsing the product.

solvents

Semi-polar solvents are essential components of the present invention. As will be shown below by way of example, it is believed that the presence of a solvent determines the effect of fatty acid foam enhancement in the acidic solution and conditions the antifoam effect of the fatty acid in the alkaline solution.

Preferred solvents have a dielectric constant of from 5 to 10.

Preferably, the solvent is selected from: propylene glycol mono-butyl ether, dipropylene glycol mono-n-butyl ether, propylene glycol mono-tert-butyl ether, dipropylene glycol mono-tert-butyl ether, diethylene glycol hexyl ether, ethyl acetate, ethanol, ethylene glycol ether, ethyl ether, ethylene glycol ether .

Preferred solvents are glycol ether solvents and these are preferably selected from the group consisting of propylene glycol mono-n-butyl ether (available as Dowanol PnB (RTM) and diethylene glycol mono-butyl ether (available as Butyl Digol (RTM) or Butyl Carbitol (RTM)). These solvents are particularly advantageous because of their cost, availability and safety factors, and we have found that this choice of solvents provides increased cleaning performance in terms of inks and dyes, and increased product stability, as well as conditioning the antifoam behavior of the composition upon rinsing.

Preferred ranges for the ratio of total surfactant to solvent range from 1: 1 to 10: 1, preferably from 2: 1 to 5: 1. A narrower ratio is preferred for reasons of cost and product stability. Typical solvent contents are 1 to 30% by weight of the composition, preferably 2 to 20% by weight of the composition, in order to obtain an effective solvent concentration when diluting the concentrates.

buffers

Buffers are essential components of the compositions of the present invention.

It is believed that the presence of a buffer is essential to ensure that the pH of the undiluted mixture is maintained at an acidic pH, below pK _{and of the} fatty acid. However, the pH must not be strongly buffered, since then excess water is required to raise the pH above the pK _and fatty acid.

In addition, if strongly acidic solutions are to be avoided in order to reduce damage to the cleaned surfaces, some reserve acidity is required so that the foam is not rapidly destabilized by the formation of insoluble calcium soaps to reduce the descaling effect of the compositions.

A preferred buffer system comprises a polycarboxylic acid and a base selected from ammonium hydroxide or alkali metal hydroxides and / or organic amines may also be used. Ammonium hydroxide is particularly preferred because it is believed to provide increased removal of calcium soap impurity, although sodium hydroxide also gives good results. Preferably such a system will buffer the product to a pH of 2 to 6.

It is preferred that the buffer system is such that pK _and fatty acid are achieved by adding more than 10 volumes of water to the product. The alkalinity and hardness of the added water will have some effect on the quantity of water required to raise the pH above pK _a .

For typical surfactant contents of 4 to 6 weight percent of the product, the buffer system should be selected such that the pH is raised above pK _{and the} fatty acid when less than 1000 volumes of water are added.

A particularly preferred pH range of the product is from 3.14 to 4.9, a pH of about 4 being most preferred, since certain enamels are sensitive to pH below 3 and low pH products may consume excessive rinsing to neutralize the mixture with low alkalinity water. It is believed that the presence of the polycarboxylic acids in the formulations in the form of salts rather than in the acid form results in a better foam, and so it is preferred that the pH of the mixture be above the lowest pK _and polycarboxylic acid present. Preferred polycarboxylic acid, citric acid has pK _and values of 3.14, 4.77 and 6.39, and subsequently pH values above 3.14 are preferred.

sequestrants

Weak sequestrants in the form of organic polycarboxylic acids are essential components of the compositions of the present invention. The presence of these weak sequestrants improves cleaning performance. These components are believed to bind weakly bound calcium ions which are present at the contact of the contaminants with the surfaces, thereby facilitating the removal of these contaminants.

Strong sequestrants may also be present. However, sequestrants such as EDTA are less advantageous for environmental reasons, since it is believed that such poorly degradable sequestrants can solubilize heavy metals from sediments at the bottom of the rivers. Moreover, EDTA and other strong sequestrants tend to form complexes with calcium in drinking water and prevent the formation of the above-mentioned antifoam calcium soap.

Preferably, the sequestrant is selected from citric, adipic, succinic, maleic, glutaric, mixtures or salts thereof. Typical levels of sequestrant are in the range of 1 to 10% by weight, preferably 3 to 6% by weight of the product.

Most preferably, the sequestrant is citric acid or a salt thereof. Citric acid is a weak sequestrant for calcium, available from renewable sources and is rapidly biodegradable.

Citric acid is particularly preferred both as a sequestrant and as a component of a buffering system, preferably at levels of 3 to 6% by weight of the product.

Fatty acids

C10 to C22 fatty acids are essential components of the compositions of the present invention.

It is believed that shorter-chain fatty acids do not form sufficiently insoluble calcium soaps and longer-chain fatty acids are too insoluble in the compositions to act as antifoams. Moreover, these medium chain fatty acids are commercially available at a reasonable price and come from renewable sources.

The fatty acids may be linear or branched, saturated or unsaturated, but are preferably naturally derived linear fatty acids.

Linear fatty acids with an average length of C 12 to 06, preferably C 14, (obtainable from lauric oils such as coconut or palm kernel fat) are particularly preferred. Larger chain length soaps are less soluble in the absence of expensive hydrotropes or organic solvents.

Typical levels of fatty acids range from 0.1 to 3% by weight of the product, with a particularly preferred range from 0.5 to 1% by weight.

It is important that the pH of the mixture is below the pK _{< 3 > of the} fatty acid that is used. Generally, the pK _{and the} O 2 to C 6 fatty acids are close to 4.9, then the pH of the mixtures will be below this value. Taking into account the requirement that the pH is above pK _and polycarboxylic acid, the pH of the mixture will generally be in the range of 3.14 to 4.9.

Surfactants

The at least one anionic non-soap surfactant is an essential component of the compositions of the present invention.

Preferred surfactants include one or more of primary and secondary alcohol sulphates, alkoxyalkoxy sulphates, primary and secondary alkane sulphonates, and alkylarylsulphonates. In the absence of anionic surfactant, the products of the present invention exhibit less effective adhesion.

Preferably, the ratio of fatty acid to anionic surfactant falls within the range of 1: 4 to 1:20, particularly preferably about 1: 5 to 1:10, expressed as% by weight of fatty acid to% by weight of the anionic surfactant in the product. This provides a good balance between foaming and cleaning performance.

Preferably, the anionic surfactant is a primary alcohol sulfate (PAS), a foaming readily biodegradable surfactant.

Preferred primary alcohol sulfates (PAS) include mixtures of materials of the general formula:

Rosa ₃ X wherein R is a Cg-C ^ g primary alkyl group and X is a solubilising cation. Suitable cations include sodium, magnesium, potassium, ammonium, and mixtures thereof.

We have found that mixtures containing magnesium PAS and a partially neutralized organic acid with a base have improved cleaning performance, especially with respect to calcium soap and limescale, while maintaining effectiveness on fat / greasy contaminants. Consequently, particularly preferred embodiments of the invention include magnesium in a molar ratio of 0.1 to 0.8 moles of Mg per mole of primary alcohol sulfate.

It should be noted that the use of magnesium alone as a counterion for PAS can lead to difficulties in the presence of polycarboxylic acid, so it is preferred that the molar ratio of counterions for PAS is such that the approximate ratio of Mg to other counterions does not exceed about 5: 1. Ratios of MgPAS to MaPAS of greater than 1: 1 but less than 2: 1 are particularly preferred.

Particularly preferred PAS molecules are those having a major proportion of C 1-8 to C 1-4 alkyl residues.

As mentioned above, these surfactants can be obtained by forming primary alcohol sulphates from fatty acids obtained from renewable sources such as coconut oil, although they can also be obtained from synthetic alcohol sources. These surfactants exhibit very acceptable biodegradability.

Suitable additional surfactants are selected from cationic, amphoteric and zwitterionic surfactants as well as mixtures thereof.

The presence of a nonionic surfactant is preferred. Preferred nonionic surfactants are alkoxylated alcohols and preferred alkoxylated alcohols are selected from the group of ethoxylated alcohols of the formula:

R ₁ - (OCH ₂ CH ₂ ) _m -OH where R 1 it is straight or branched C 8 to C 8 alkyl or hydroxyalkyl and the average degree of ethoxylation m is 1 to 14, preferably 3 to 10, for good fat contamination detergent.

Starting materials for the synthesis of these ethoxylated alcohols, minor components of the surfactant system, are available from both natural and synthetic sources.

Most preferably, the surfactant system comprises a mixture of sulfates of primary alcohols and alkoxylated alcohols. For the purposes of this document, alkoxylated alcohols include alkyl or hydroxyalkylethoxylated alcohols.

Preferably sulfates of primary alcohols and alkoxylated alcohols are present in a ratio of from 3: 1 to 1: 1, with a ratio of about 2: 1 being particularly preferred.

Particularly preferred compositions include 15 to 30 wt% primary alcohol sulfate and 5 to 15 wt% nonionic surfactant. These relatively high levels of PAS and nonionic surfactant are required to form concentrated compositions which can be transported more efficiently and require less packaging material.

Preferably the total surfactant levels comprise 1 to 40% by weight of the product, with levels of 2 to 10% by weight, which are preferred for domestic use as unconcentrated formulations. Surfactant levels of 20-40% by weight, more preferably 25-35% by weight are preferred for concentrates, although antifoam components may be required at the highest surfactant levels

Minor ingredients and other materials

The compositions of the invention may further comprise other ingredients selected from the group consisting of: perfumes, colorants, hygiene agents, viscosity modifiers, and mixtures thereof. In certain embodiments of the invention, it is useful to incorporate additional suds control agents into the formulation.

Preferably, other suds control agents include hydrophobic oils. More preferably, the hydrophobic oil is a straight or branched chain hydrocarbon or silicone oil, more preferably the hydrophobic oil is paraffin.

Most preferably, the hydrophobic oil is a paraffin with a 50% by weight boiling point in the range of 170 to 300 ° C. The term 50% by weight boiling point is meant to indicate that 50% by weight of paraffin can be distilled off at a temperature in this range. In general, the boiling point limits of aqueous paraffins for use in the compositions of the present invention lie between 171 and 250 ° C. We have found that isoparaffins, i. branched paraffins are particularly effective in comparison with other hydrophobic oils such as n-decane and n-tetradecane.

The content of the solubilized hydrophobic oil in embodiments of the invention is typically in the range of from 0.2 to 5% by weight, preferably from 1.0 to 2.0% by weight. When a hydrophobic oil is present, the preferred ratio of fatty acid to hydrophobic oil is in the range of 0.5 to 1: 1 to 0.5, preferably about 1: 1. These ratios form a particularly effective antifoam system.

Preferably, the compositions of this invention are homogeneous, more preferably translucent and most preferably transparent. Typical viscosities are 1 to 200 mPas at a shear rate of 21 sec ^- 2 measured at 25 ° C.

packing

It is preferred that the compositions of the invention are provided in a package adapted to form a product spray, preferably a foam spray, although the possibility of other dispensing and delivery systems is not intended to be excluded.

In view of all of the above, preferred embodiments of the present invention include acidic aqueous cleaning compositions comprising:

(a) 2 to 40% by weight of the surfactant comprises a primary alcohol sulphate and preferably one or more non-ionic surfactants, wherein at least 50% by weight of the surfactants present is a primary alcohol sulphate as the principal surfactant

b) 0.2 to 5% by weight of a C 10 to C 18 unbranched fatty acid as a foam enhancer under acidic conditions and as an antipoaming agent under basic conditions.

c) at least one solvent selected from glycol ether and 1 to 5 carbon alcohol solvents, in an amount such that the surfactant to solvent ratios fall within the range of 1: 1 to 10: 1;

(d) 1 to 10% by weight of a water-soluble organic acid selected from citric, adipic, succinic, maleic, glutaric, mixtures or salts thereof, as a sequestrant for calcium and magnesium and as a buffer system component, and

e) a sufficient base to obtain a pH of the mixture in the range of 3.14 to 4.9.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to further understand the invention, it will be further illustrated by way of examples and with reference to the accompanying drawings wherein:

Figure 1: shows the effect of the formulation on the number of rinses required to reduce the volume of foam with water of varying hardness.

Figure 2: shows the effect of pH on foam volume with water of different hardness.

DETAILED DESCRIPTION OF THE INVENTION

Examples 1-2

The mixtures were prepared according to Table 1 below. All ingredients were mixed at room temperature and filled into a spray bottle. The nonionic 16 surfactant was DOBANOL 23-6.5 EO (RTM ex. SHELL), the PAS was DACPON-27L (RTM ex. DAC). Butyl Carbitol is a trademark of Union Carbide. The fatty acid was PRIFAC 7901 (RTM ex. Unichema).

Table 1

Example 1 Example 2 citric acid 4% 4% waist (anionic PAL) 4% 4% neónová PAL 2% 2% butyl carbitol 2% 2% (solvent) perfume 0.5% 0.5% sodium hydroxide 1,2% 1,2% protective substance 0.015% 0.015% fatty acid - 0.5% Water up to 100% up to 100% PH 4.3 4.3 adherence 2.7 3.6

(PAL - surfactant)

Efficacy was evaluated by spraying the product on a non-horizontal surface and rinsing with hard water (typically> 26 ° French). The adherence was estimated by a panel of twenty trained technicians instructed to evaluate the foam adherence in the blind test on a scale of 1 to 5 by a value of 1 representing a weak adherence and a value of 5 representing an excellent adherence.

Example 1 is a commercially available product selected as a comparative example; the effectiveness of this product was good.

Example 2 is an example of the present invention, the formulation exhibiting a bulkier and more adherent foam that was particularly effective in adhering to inclined or vertical surfaces. While the mixture of Example 1 showed acceptable adherence and could be rinsed without particular difficulty, it was found that the mixture of Example 2 showed improved adhesion and was rinsed with exceptional ease.

Examples 3 to 8

Figure 1 shows the effect of the formulation on the number of rinses required to reduce the foam volume with water of varying hardness.

The measurements were made as follows: 5 mg of the product was diluted to 50 ml with water-marked hardness in a separatory funnel with a graduated scale. The funnel was shaken vigorously in the hand for approximately ten seconds to generate foam and the initial foam volume was marked after excess fluid was drained through the tap. Aliquots of 50 ml of water were used for each rinse, added to the funnel with an additional shaking cycle and additional foam volume measurement after liquid removal. This procedure is repeated as long as the foam remains. The mixtures used were as in Example 1 and 2 above, with a fatty acid level of 0.5% by weight.

It can be seen from the figure that the addition of a fatty acid to the comparative example caused a reduction in the number of required rinsing cycles in all cases, and that the improvement was more significant for harder waters.

Figure 2 shows the effect of pH on the foam volume for water of different hardness. Said pH is the pH of the liquid obtained during the above-described rinsing cycles. It can be seen that with the rinsing process the pH of the liquid increases. It can be seen that for waters containing exceptionally high calcium levels, the effect of the fatty acid was very pronounced. For more common water, the foam volume dropped rapidly as the pH rose above 6.5 from pH 4-5 of the original product at 10% dilution.

From the above examples, it can be seen that these compositions exhibit both improved foam adhesion and improved rinsing compared to the prior art composition.

Examples 9 to 15

Table 2 below lists the values for the compositions of Example 2 in which the mean chain length of the fatty acid was variable. The values for the mixture of Example 1 without fatty acid are given for comparison. The cumulative foam volume, (CFV ") is measured in cubic centimeters for the standard initial volume and the shaking protocol as described above with reference to Examples 3 to 8. CFV refers to the total volume of foam produced in the rinsing process using 26 ° French water. The number of foam rinses required was determined as described above.

Table 2

fatty acid CFV rinse Example 9 Example 1 4950 9.5 Example 10 C8 3025 8.5 Example 11 CIO 2400 8.0 Example 12 C12 2525 5.0 Example 13 C14 400 4.0 Example 14 C18 375 6.0 Example 15 C22 975 6.0

From the above, it can be seen that fatty acids with a chain length> C12 significantly reduce CFV. It was noted that fatty acids with a chain length> 22 were insoluble in the mixture.

Examples 16 to 19

The sequestrant type effect is demonstrated in Table 3 below, in which the sequestrant type was changed in the presence and absence of fatty acid (FA). The cumulative foam volume, (CFV), is measured in cubic centimeters for the standard initial volume and shaking protocol as described above with reference to Examples 3 to 8. CFV refers to the total volume of foam produced in the rinsing process using 26 ° French water. The number of foam rinses required was determined as described above.

Table 3

FA citrate EDTA CFV rinse. Example 16 - (Example 1) 4% - 3800 8.5 Example 17 0.5 (Exam.2) 4% - 3375 5.5 Example 18 - - 4% 3850 7.5 Example 19 0.5 - 4% 3400 5.5

It can be seen from Table 3 above that better results are obtained with the presence of a fatty acid and a sequestrant.

Examples 20 to 26

The pH effect is demonstrated by reference to the values given in Table 4 below. CFV measurements and rinsing were performed as mentioned above using a water hardness of 12 ° and 26 ° French. The results are generally given for 26 ° French water, although similar results were obtained with softer water (Examples 25 and 26). Examples 20, 22 and 23 are comparative examples.

Table 4

FA pH CFV rinse. Example 20 - (Example 1) 4.3 3800 8.5 Example 21 0.5 (Exam.2) 4.3 3375 5.5 Example 22 - 10.5 3625 9.0 Example 23 0.5 10.5 1400 3.0 Example 21 0.5 c. 2.5 2325 5.5 Example 22 0.5 4.3 3400 6.0 Example 23 0.5 c. 2.5 5100 9.0

The results presented above show that the anti-foaming effect is very significant in alkaline products. However, these alkaline mixtures do not effectively remove limescale. Examples 24 and 26 show the effect of omitting the alkaline component (NaOH) from the buffer of the mixture. The mixture of Example 24 shows similar behavior to the compositions of the invention in hard water, but is too acidic for use on some surfaces. Examples 25 and 26 with softer water of 12 ° French show that embodiments of the invention (Example 25) show acceptable rinsing, whereas in the absence of an alkaline component (Example 26) of the buffer, weak antifoam effects are seen.

It was also noted that the foams formed by the compositions at a pH of about 2.5 had low adhesion and poor cleaning performance.

Examples 27 to 30

In Examples 27 to 30 shown in Table 5, the synergistic relationship of solvent and antifoam fatty acid is shown. The results were. obtained as described above.

Table 5

FA solvent CFV rinse. Example 27 - (Example 1) 2% 3800 8.5 Example 28 0.5 (Exam.2) 2% 3375 5.5 Example 29 - - 2325 7.0 Example 30 0.5 - 2750 7.0

From the above results, it can be seen that the presence of a solvent is essential for the fatty acid to exhibit an antifoaming effect upon dilution. In the absence of solvent (Comparative Examples 29 and 30), a low foam with low tack was obtained. In the presence of a solvent, the foam is stabilized when the fatty acid is omitted (Comparative Example 27). Only in the presence of both fatty acid and solvent are the advantages of high initial foam volume and rapid rinsing obtained (Example 28).

Examples 31 to 36

In Examples 31 to 36 shown in Table 6, a synergistic effect on product properties is shown. changes in the surfactant system. The results are obtained as described above using a water hardness of 26 ° French.

Table 6

FA anionic PAL nonionic Pal CFV rinse. Example 31 - (Example 1) 4% 2% 3800 8.5 Example 32 0.5 (Exam.2) 4% 2% 3375 5.5 Example 33 - - 2% 150 3.0 Example 34 0.5 - 2% 0 0 Example 35 - 4% 4700 7.0 Example 36 0.5 4% 3900 4.5

Comparative Examples 33 and 34 show that in the absence of an anionic surfactant little or no foam is formed and the product flows rapidly from the inclined surface during cleaning operations. Examples 35 and 36 show the effect of omitting a nonionic surfactant optional in embodiments of the invention. Comparative Example 35 can be seen. that the nonionic surfactant has some foam suppressing activity, although the rinsing time in the presence of the nonionic surfactant increases. From these results it can be seen that while the fatty acid and at least one other anionic surfactant are essential ingredients, the nonionic surfactant is optional.

Examples 37 to 39

In Examples 37-39 below (see Table 7), the efficacy of the formulations of this invention is compared to the commercial formulations.

Table 7

Example 37 38 39 PAS Magnesium Salt 18.5 - - PAS sodium salt - 3.5 - SAS sodium salt - - 4.0 Neónová PAL 9.5 - - solvent 8.0 - - Fatty acid 0.7 - - isoparaffin 0.75 - - ammonia 1, 1 0.75 - Organic acid 6.0 6.0 6.2 Minority ingredients tracks tracks tracks Water up to 100% up to 100% up to 100%

Continuation of Table 7

Example 37 38 39 pH 4.0 sour sour Contamination / Contact time Kitchen 15 p 4 3 2 Grease contamination 15 sec 3 3 3 30 p 3 3 3 60 s 4 4 3 Soap dirt 180 s 3 1 0 240 s 4 2 1

Table 7 lists two comparative examples (Examples 38 and 39) of conventional commercially available acidic cleaning compositions for bathrooms. These compositions were obtained by analysis. In the mixture of Example 39, the organic acids were mixtures of succinic, glutaric, adipic and benzoic acids, a total of 6.2% by weight. In Examples 37 and 38, citric acid was used. It can be seen that the blend of Example 38 differs from the present invention in that it does not use the magnesium salt of PAS and no fatty acid or solvent is present.

Contaminated tiles with synthetic soap contamination, greasy contamination, and kitchen contamination were prepared to evaluate mixtures 37-39. Each contamination contained visible traces of carbon black as a visualization reagent.

The soap contamination consisted essentially of calcium stearate applied to enamelled steel tiles by spraying a suspension of calcium stearate in isopropyl alcohol. The tiles were baked at 180 ° C for 30 minutes after contamination.

The fatty contamination consisted of a mixture of fatty acids 24 and paraffin applied to ceramic tiles by spraying the mixture in petroleum ether.

Kitchen contamination consisting of a mixture of fats, fatty acids, paraffin and clay was applied to ceramic tiles by spraying the mixture in petroleum ether.

To evaluate the efficacy of the mixture, 0.5 ml of the mixtures of Examples 37 to 39 were applied to each contaminated tile and left in contact with the tile for the time indicated in Table 7 as the contact time. The tiles were mechanically wiped with a clean damp cloth one time at constant pressure. The residual contamination was evaluated visually on a six-point scale from 0 to 5, where 0 indicates no contamination removed and 5 indicates complete contamination removal as indicated by soot removal.

From the above results, it can be seen that the compositions of the present invention are equivalent to known compositions in terms of removal of fat soils, but greatly improved in terms of removal of kitchen soils and especially soap soils.

Examples 39 to 43

Examples 39 to 44 below in Table 8 illustrate the effect of changes in the Mg to Na ratio as counterions for the PAS surfactant at high concentrations. All formulations were similar to the formulation of Example 37 except that the Mg: Na PAS ratio was variable.

Table 8

Example MgPAS: NaPAS 39 10.5: 8.0 stab.í Other 40 11.0: 7.5 stable 41 18.5: 0.0 unstable 42 17.7: 1.0 unstable 43 15.0: 3.5 unstable

In Examples 41 to 43, it was found that magnesium citrate precipitated from the product upon prolonged storage, while Examples 39 to 40 were stable upon storage. The products of Examples 41-43 were otherwise acceptable.

Claims (22)

1. An aqueous cleaning composition comprising: (a) a surfactant system containing an anionic surfactant other than an alkali metal salt of a fatty acid; b) a C 10 to C 22 monocarboxylic fatty acid c) semipolar solvent, (d) polycarboxylic acid and its salt; and e) a base, and the mixture has a pH of less than 6. Composition according to claim 1, characterized in that the semipolar solvent has a dielectic constant of from 5 to 35. 3. The composition of claim 1 wherein the semipolar solvent is selected from propylene glycol-mono-n-butyl ether, di propylene glycol-mono-n-butyl ether, propylene glycol mono-tert-butyl ether. , dipropylene glycol mono-t-butyl ether, diethylene glycol hexyl ether, ethyl acetate, ethanol, isopropyl alcohol, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, and mixtures thereof. The composition of claim 3, wherein the semipolar solvent is a glycol ether solvent. 5. The composition of claim 4 wherein the semipolar solvent is selected from the group consisting of propylene glycol mono-n-butyl ether and diethylene glycol mono-butyl ether. A composition according to claim 1, wherein the level of solvent is in the range of 1 to 30% by weight of the product. 7. The composition of claim 6 wherein the ratio of total surfactant to solvent is in the range of 2: 1 to 5: 1. A composition according to claim 1, characterized in that it contains 1 to 10% by weight of polycarboxylic acids or salts thereof. The composition of claim 8, wherein the polycarboxylic acid is selected from the group consisting of citric, adipic, succinic, maleic, glutaric acid, salts thereof, and mixtures of acids or salts thereof. The composition of claim 1, wherein the reserve acidity of the composition is such that the pH exceeds pK _and monocarboxylic acid by adding more than 10 volumes of water at a pH of at least 7.5 to one volume of product. The composition of claim 1, wherein the reserve acidity of the composition is such that the pH is raised above pK _and monocarboxylic acid when more than 1000 volumes of water with a pH of at least 7.5 are added to one volume of the product. t ý 0,1 The composition of claim 1, wherein the pH range is from 3.14 to 4.9. 13. The composition of claim 1, wherein the level of monocarboxylic acid is up to 3% by weight of the product. at I ^t is in CA, JUNE CA is in the range of 14. The composition of claim 1 wherein the at least one anionic surfactant is selected from the group consisting of: primary and secondary alcohol sulfates, alcohol ethoxy sulfates, primary and secondary alkane sulfonates, alkylarylsulfonates, and mixtures thereof. 15. A composition according to claim 1 comprising a nonionic surfactant. 16. A composition according to claim 1 comprising a surfactant selected from a primary alcohol sulfate and an alkylbenzene sulfonate together with an alkoxylated alcohol in a ratio of from 3: 1 to 1: 1. 17. The composition of claim 1 wherein the ratio of monocarboxylic acid to anionic surfactant is in the range of 1: 4 to 1:20. 18. The composition of claim 1, wherein the level of surfactant mass product. 19. The composition of claim 1, wherein the level of surfactant weight products. The substance is effective and is 2 to 10% The substance is effective and is 20 to 40% 20. The composition of claim 1 wherein the package is adapted to form a product spray. 21. The acidic aqueous cleaning composition of claim 1, comprising: (a) 2 to 40% by weight of a primary alcohol sulphate-containing surfactant and preferably one or more non-ionic surfactants, wherein at least 50% by weight of the surfactant present is a primary alcohol sulphate; (b) 0,2 to 5% by weight of C10 to C18 unbranched fatty acid; c) at least one solvent selected from the group of glycol ether and 1 to 5 carbon alcohol solvents, in an amount such that the surfactant to solvent ratios fall within the range of 1: 1 to 10: 1; (d) 1-10% by weight of a water-soluble organic acid selected from citric, adipic, succinic, maleic, glutaric, their salts or mixtures thereof, and e) a sufficient base to obtain a pH of the mixture in the range of 3.14 to 4.9. 1,200 Ian liane .. = peninsula water 26 'liane. = water of the Prenlon tank 48 liane. = water of llaubordine 1.200 / ANOcI JAÍZIÍaO CC • V -c >> IN, O 'M I liane. = peninsula water 26 liane. = water of the Prcnon tank 48 'liane. = water of Haubordine