SK280781B6 - Hard surface cleaning compositions - Google Patents

Abstract

The invention provides liquid cleaninig composition of pH 3 - 7, comprising: a) 1 - 30 %wt nonionic surfactant; b) 0.005 - 5 %wt of a water soluble, anionic polymer having an average molecular weight less than 1,000,000, said polymer being free of quaternary nitrogen groups, whilst polymer-to-nonionic surfactant is 0.1 or less.

Description

Technical field

The invention relates to liquid cleaning compositions of general use, in particular for hard surfaces, which contain surfactants and polymeric components.

BACKGROUND OF THE INVENTION

In traditional cleaning of hard surfaces such as wood, glazed tiles, coated metals and the like, it is known that the removal of contamination is achieved by the use of a solvent-based surfactant or mixture, with the application of varnish, wax or polish as a separate protection operation. surface and to reduce the rate of pollution reduction. This two-step cleaning and protective operation is time-consuming and complex.

The incorporation of certain ingredients into surfactant-based compositions with the intention that the entrapment of such ingredients onto surfaces will provide a protective layer in a one-step cleaning operation is known.

US 3679592 (1972) discloses alkaline cleaning anti-fouling compositions which comprise a surfactant and 1 to 10% by weight, especially 4% by weight, of a film-forming component having a specific structure having a molecular weight in the range of 500 to 100000. The use of the compositions is intended to retard stain deposition and to help remove pollution.

GB 1528592 (1978) discloses alkaline floor cleaning compositions comprising an organic polycarboxylic acid copolymer having a molecular weight in the range 100000 to 2500000, which is soluble in aqueous solutions at pH 8.5 or higher. These polymers are readily available in commercial quantities.

GB 1534722 (1978) discloses granular hard surface cleaning compositions which comprise a surfactant and a polyvinyl alcohol or pyrrolidone and a biopolysaccharide as a composition to improve soil removal. These polymers have molecular weights ranging from about 5000 to about 360000 and are available in industrially useful amounts. The mixtures form alkaline solutions.

US 4252665 (1979) discloses aqueous alkaline cleaning compositions for hard surfaces at pH 9-12 which include a detergent-enhancing acrylic copolymer having a molecular weight substantially in excess of 100,000 in conjunction with anionic surfactants.

US 07/297807 described in EP 0467472 A2 (Colgate Palmolive) shows that the incorporation of a 2.3% by weight 15-20% aqueous solution of a cationic polymer poly [beta (methyldiethylammonium) ethyl methacrylate] in a mixed nonionic hard surface cleaning system will significantly reduce the subsequent re-cleaning of previously soiled and cleaned ceramic tiles. These cationic polymers are much more expensive than conventional acrylic and methacrylic polymers and there is some doubt about the environmental acceptability of cationic nitrogen-containing cationic substances.

It is known that surfactant-based cleaning compositions contain structuring agents to assist in providing suitable rheological properties to increase their distribution and adherence of the composition to the hard surface to be cleaned, in particular to provide increased adhesion to the inclined surfaces.

Known structuring agents include polymers such as polysaccharides such as sodium carboxymethylcellulose and other chemically modified cellulosic materials, xanthan gum and other non-flocculating structuring agents such as the PS87 Biopolymers disclosed in U.S. Pat. Acrylic acid polymers crosslinked with polyfunctional agents such as CARBOPOIΛ are also used as structuring agents. The amount of such structuring agents may be at least 0.001% by weight, but is more typically at least 0.01% by weight of the composition. Another function of such structuring agents is to suspend particulate impurities such as abrasives.

It is also known to use at least partially esterified resins, such as at least partially esterified adduct of a rosin and an unsaturated dicarboxylic acid or anhydride, or at least partially esterified derivatives of copolymerization products of monounsaturated aliphatic, cycloaliphatic or aromatic monomers which do not have carboxylic groups or unsaturated dicarboxylic acid as additives. The purpose of such materials is to modify the wetting properties of the mixture so as to produce a smear-free final effect upon drying.

Typical examples of suitable copolymers of the latter type are copolymers of ethylene, styrene and vinyl methyl ether with maleic acid, filmaric acid, itaconic acid, citraconic acid and the like, and their anhydrides including styrene / maleic anhydride copolymers.

EP 0467472 A2 discloses that soil release polymers such as, but not limited to, cationic poly [beta (methyldiethylammonium) ethyl methacrylate] are also effective in combination with an anionic and cationic surfactant. It is stated in this published application that these adsorbed polymers form a residual anti-fouling hydrophilic layer of the soil-promoting polymer on the surface, whereby removal of the subsequently contaminated contaminants requires less work than in the absence of the residual layer. The molecular weight range of the polymers falls within the range of 4000 to 100000, although the use of polymers with a molecular weight above 50,000 is not recommended for solubility reasons (see EP 467472, page 3, paragraph 3).

EP 0379256 discloses similar compositions to said document having up to 2% by weight of an optionally quartemized antistatic polymer having a molecular weight ranging from 2000 to 500000 and characterized by an acidic pH of from 2 to 4 and 2 to 4% by weight of a nonionic surfactant system . Specific examples relate to compositions having a pH of 2.5 and containing 2.2% by weight of a mixed nonionic surfactant system and 0.07% by weight of the specified cationic polymer. The modified polymer further has the function of a soil release agent.

In addition, it is known from US 4606842 to use low molecular weight polyacrylic resins as detergent builders in spray and wipe glass cleaning compositions. Baker et al. in US 4690779 describes the use of a combination of polyacrylic acid polymers with a molecular weight below 5000 with certain nonionic surfactants in hard surface cleaning compositions. The primary function of the polymer in these systems is its use as a detergent builder.

US 4678596 relates to a rinse aid for manual dishwashing and for machine dishwashing with a pH of 7.5 to

10, which contains 5 to 60% by weight of a nonionic surfactant system (15% by weight in the example) and preferably 2% by weight of an anionic polymer of poly (meth) acrylic acid with a molecular weight

Mixtures having a pH of 6.5 containing relatively high levels of polymer are reported to be unstable.

US 4657690 relates to a hair and skin cleansing and foaming composition in an acid / neutral pH range (4.5 to 7.7) that includes a nonionic surfactant (typically about 5% by weight) and poly (meth) acrylic acid for improvement a primary detergent surfactant, wherein the weight ratio of polymer to surfactant is not greater than 0.2: 1.

It can be seen from the above that it is known to include certain polymers in generally alkaline hard surface cleaning compositions to obtain either a better primary cleaning effect when the composition is first applied to the surface or a secondary cleaning effect by modifying the surface, thereby preventing fouling or otherwise facilitating repeated cleaning. As will be illustrated below by way of example, the known mixtures are generally ineffective in both primary and secondary purification.

SUMMARY OF THE INVENTION

It has now been found that the use of certain relatively long-chain anionic water-soluble polymers in an acidic or neutral surfactant-based composition provides a surprising initial cleaning benefit in addition to the anti-fouling benefit. We have surprisingly found that conventional polymers derived from acrylic, methacrylic and maleic anhydride have this effect in acidic solutions of nonionic surfactants to the same extent as expensive cationic polymers.

Accordingly, the invention provides a hard surface cleaning liquid composition having a pH of 3 to 7, comprising:

(a) 1 to 30% by weight of non-ionic surfactant;

b) 0.005 to 3% by weight of a water-soluble anionic polymer having an average molecular weight of less than 1000000, said polymer being free of quaternary ammonium groups, wherein the ratio of polymer: nonionic surfactant is 0.1: 1 or less.

Without wishing to be limited by any theory of action, it is believed that the purification benefit of the water-soluble polymer results from phase separation of the nonionic surfactant causing leakage and / or entrapment to the contaminant, resulting in a higher effective surfactant concentration than in mixtures which they are polymer free. An alternative explanation is that the entrapment of the surfactant on the contaminated surface can be enhanced by formation and entrapment of the polymer-surfactant complex.

polymers

The water-soluble polymer of this size range is an essential component of the compositions of the present invention. Surprisingly, preferred polymers in embodiments of the invention are those that are readily available on the market. They are polymers of acrylic anhydride or methacrylic acid or maleic acid, or copolymers of one or more of them, either together or with other monomers.

Particularly suitable polymers include polyacrylic acid, polymaleic anhydride and copolymers of any of the foregoing with ethylene, styrene and methyl vinyl ether.

Most preferred polymers are copolymers of maleic anhydride, preferably those formed with styrene, acrylic acid, methyl vinyl ether and ethylene.

Preferably, the molecular weight of the polymer is at least 5000, more preferably at least 50,000 and most preferably exceeds 100,000. Typically, the surfactant-based compositions comprise at least 0.01% by weight of the polymer of the product.

It has unexpectedly been found that this positive effect of the presence of a polymer can only be identified if very low levels of polymer and surfactant are present. This low concentration threshold property is particularly advantageous in the applications of the present invention where significant dilution is expected.

Preferably, the polymer level is 0.05 to 5.0% by weight at which the anti-redeposition effects become particularly significant. More preferably, 0.2 to 2.0% by weight of the polymer is present. We have found that higher polymer levels do not provide a significant additional advantage with conventional dilution factors to increase the cost of the blend. It is believed that high levels of polymer increase the viscosity of the product and prevent the product from wetting and penetrating contamination. However, for concentrated products that are diluted prior to use, the initial level of the polymer may be as high as 5% by weight.

In the context of the present invention, anionic polymers are those which carry a negative charge or similar polymers in protonated form. Mixtures of polymers may be used.

As mentioned, the molecular weight of the polymer is below 10,000,000. With increasing molecular weight? the cleaning performance of the polymer decreases. Surfactants

It is essential that the compositions of the present invention comprise at least one nonionic surfactant. The compositions of the present invention include detergent actives which may be selected from nonionic detergent actives. We have found that a detrimental effect occurs when anionic polymers are used together with only the anionic surfactant or a mixture of anionic and nonionic surfactant which contains a lot of anionic surfactant.

Suitable nonionic detergent actives can be broadly described as being produced by the condensation of alkylene oxide groups having a hydrophilic nature with an organic hydrophobic substance, which may be aliphatic or aromatic in nature.

The length of the hydrophilic or polyoxyalkylene radical which is condensed with some particularly hydrophobic group can be readily adjusted to obtain a water-soluble substance having the desired degree of equilibrium between hydrophobic and hydrophilic elements.

Particular examples include the condensation products of aliphatic alcohols having from 8 to 22 carbon atoms in the chain either in a straight or branched configuration with ethylene oxide, such as coconut oil-ethylene oxide condensate having from 2 to 15 moles of ethylene oxide per mole of coconut alcohol; alkylphenol condensates having an alkyl group of from 6 to 12 carbon atoms with 5 to 25 moles of ethylene oxide per mole of alkylphenol; condensates of the reaction product of ethylenediamine and propylene oxide with ethylene oxide, condensates containing from 40 to 80% by weight of polyoxyethylene radicals and with a molecular weight of from 5000 to 11000; tertiary amine oxides of the structure R ₃ NO, where one R group is an alkyl group of 8 to 18 carbon atoms and the other are

Methyl, ethyl or hydroxyethyl groups such as dimethyldodecylamine oxide; tertiary phosphine oxides having the structure R ₃ PO, wherein one R group is an alkyl group of 10 to 18 carbon atoms and the other are alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms, for example, dimethyldodecylphosphine oxide; and dialkyl sulfoxides having the structure R ₂ SO, wherein R is an alkyl group of 10 to 18 carbon atoms and the other is a methyl or ethyl group, for example methyltetradecylsulfoxide; fatty acid alkylolamides; fatty acid alkylene oxide condensates of alkyl mercaptans.

The amount of nonionic detergent active in the composition of the present invention will generally be from 1 to 30% by weight, preferably from 10 to 20% by weight, and most preferably from 12 to 20% by weight. Levels of about 15% by weight of the surfactant are particularly advantageous because a small increase in cleaning performance has been found in non-inherited use at higher levels, although such higher levels can be used in products intended to be substantially diluted before use.

Optionally, an anionic surfactant may be present in relatively small proportions.

Suitable anionic detergent actives are the water-soluble salts of organic sulfur reaction products having an alkyl radical of from 8 to 22 carbon atoms in the molecular structure and a radical selected from the radicals of sulfonic or sulfuric esters and mixtures thereof.

Examples of anionic detergents are sodium and potassium alcohol sulfates, especially those obtained by sulfating higher alcohols produced by reducing tallow and coconut oil triglycerides; sodium and potassium alkylbenzenesulfonates, such as those containing from 9 to 15 carbon atoms in the alkyl group; sodium and potassium secondary alkanesulfonates; sodium alkyl glyceryl ether sulfates, especially those higher alcohol ethers derived from tallow and coconut oil; sodium coconut-oil sulphates of monoglycidides of fatty acids; sodium and potassium salts of sulfuric acid esters of the reaction product of one mole of a higher fatty alcohol and from 1 to 6 moles of ethylene oxide; sodium and potassium salts of alkylphenolethylene oxide ether sulfate having from 1 to 8 units of ethylene oxide molecules, and wherein the alkyl radical contains from 4 to 14 carbon atoms; a reaction product of fatty acids esterified with isethionic acid and neutralized with sodium hydroxide, wherein, for example, the fatty acids are obtained from coconut oil and mixtures thereof.

Preferred water-soluble synthetic anionic detergent actives are ammonium and substituted ammonium salts (such as mono-, di- and triethanolamine), alkali metal salts (such as sodium or potassium) and alkaline earth metal (such as calcium or magnesium) of higher alkyl benzene sulfonates; mixtures with olefin sulphonates and higher alkyl sulphates, and higher fatty acid monoglyceride sulphates.

Most preferred anionic detergent actives are higher alkyl aromatic sulfonates, such as higher alkylbenzene sulfonates containing from 6 to 20 carbon atoms in the straight or branched chain alkyl group, of which particular examples are sodium salts of higher alkylbenzenesulfonates or higher alkylthiolenesulfonates, alkylsulfonate sulfonates, alkylsulfonate sulfonates, alkylsulfenesulfonates or alkylxylenesulfonates and sodium dinonylnaphthalenesulfonate.

The amount of synthetic anionic detergent active used in the composition of the invention will generally be from 0.5 to 50% by weight (of total surfactants), preferably less than 33% by weight (of total surfactants). For products containing about 15% by weight of surfactant, the level of anionic surfactant should preferably not exceed 5% by weight of the product.

It is also possible to optionally incorporate amphoteric, cationic or zwitterionic detergent active agents into the compositions of the invention.

Suitable amphoteric detergent-active substances which may optionally be used are derivatives of aliphatic secondary and tertiary amines containing an alkyl group of 8 to 18 carbon atoms and an aliphatic radical substituted with an anionic water-solubilizing group, for example sodium 3-dodecylaminopropionate and sodium dodecylaminopropionate; Sodium -2-hydroxydodecyl-N-methyltaurate.

Suitable cationic detergent actives are quaternary ammonium salts having an aliphatic radical of 8 to 18 carbon atoms, for example cetyltrimethylammonium bromide.

Suitable zwitterionic detergent actives which may optionally be used are aliphatic quaternary ammonium, sulfonium and phosphonium derivatives containing an alkyl group of 8 to 18 carbon atoms and an aliphatic radical substituted with an anionic water-solubilizing group, for example 3- (N, N-dimethyl) N-hexadecylammonium) propane-1-sulfonatebetaine, 3- (dodecylmethylsulfonium) propane-1-sulfonatebetaine and 3- (cetylmethylphosphonium) ethanesulfonatebetaine.

Other examples of suitable detergent actives are those commonly used as surfactants listed in the well-known textbook Surviving Active Agents, Volume I by Schwartz and Perry and Surviving Active Agents and Detergents, Volume II by Schwartz, Perry and Berch.

The total amount of detergent-active agent used in the detergent composition of the present invention will generally be from 1.5 to 30% by weight, preferably from 2 to 20% by weight, most preferably from 10 to 20% by weight.

Minority ingredients

The compositions of the invention may contain other ingredients which aid in their cleaning performance.

For example, the composition may contain detergent ingredients other than the specially water-soluble salts as defined herein, such as nitrilotriacetates, polycarboxylates, citrates, dicarboxylic acids, water-soluble phosphates, especially polyphosphates, ortho-pyrophosphate mixtures, zeolites and mixtures thereof. Such detergent builders may additionally act as abrasives when present in an amount in excess of their solubility in water, as explained herein. In general, detergent ingredients other than special water-soluble salts, when used, will preferably comprise from 0.1 to 25% by weight of the composition.

Metal ion sequestrants such as ethylenediaminetetraacetates, aminopolyphosphonates (DEQUEST®) and phosphates and many variations of other polyfunctional organic acids and salts can also optionally be used.

Another optional component for the compositions of the present invention is a soap control material that can be used in the compositions of the present invention which tend to form an excess of soaps when used. One example of soap control material is soap. Soaps are fatty acid salts and include alkali metal soaps such as sodium, potassium, ammonium and alkanolammonium salts of higher fatty acids containing from about 8 to about 24 carbon atoms. Particularly useful are sodium and potassium and mono-, di- and

2806 triethanolamine salts of mixtures of fatty acids derived from coconut oil and peanut oil. If used, the amount of soap may comprise at least 0.005% by weight, preferably 0.5 to 2% by weight of the composition. Another example of a soap control material is an organic solvent, hydrophobic silica, and silicone oil or hydrocarbons.

The compositions of the present invention may also contain, in addition to the aforementioned components, various other optional components such as pH regulators, dyes, optical brighteners, soil suspending agents, detersive enzymes, compatible bleaching agents, gel controlling agents, solidification-stabilizers, bactericides , preservatives, solvents, fungicides, insect repellents, detergent hydrotropes, perfumes and opacifying agents.

It is preferred that the compositions of the present invention are substantially free of abrasive particles. Experiments have shown that the presence of abrasives reduces the polymeric cleaning benefit, although the abrasives should themselves provide a separate cleaning benefit. It is believed that the abrasive, the surfactant, and the polymer form a complex that reduces the effective concentration of the surfactant on the surface to be cleaned.

As mentioned, the compositions of the invention are acidic or neutral. We have found that improved cleaning and / or re-contamination benefits are obtained at these pH values. The preferred pH of the products is in the range of 3 to 6. A pH of 4 to 6 is particularly advantageous as it provides a balance between the danger of acid mixtures and the benefits of acids for descaling.

Particularly preferred compositions of the present invention are mobile aqueous liquids having a pH of from 3 to 6, including:

(a) 10 to 20% by weight of alkoxylated alcohol, a non-ionic surfactant;

(b) less than 3% by weight of an anionic surfactant;

(c) 0,2 to 2% by weight of a water-soluble anionic polymer with an average molecular weight of less than 1000000, the polymer being a homo- or heteropolymer of at least one acrylic acid, methacrylic acid or maleic anhydride with at least one acrylic acid substance methacrylic acid, maleic anhydride, ethylene, styrene and methyl vinyl ether, and the polymer is substantially free of quaternary nitrogen groups.

In order that this invention may be further understood, it will be described herein by way of example and by reference to the accompanying drawings, in which:

Figure 1: is a graph showing the effect of polymer concentration on cleaning efforts and anti-pollution effect; and Figure 2: is a graph showing the relationship of primary and secondary cleaning benefits for different types of polymer.

DETAILED DESCRIPTION OF THE INVENTION

Examples 1 to 8 use materials such as: Sokolan (TM) ex. BASF series Gantrez (TM) ex. GAF

Scripset 520 (TM) ex. Monsanto

EMA 31 ex. Monsanto

SCMC (Courlose A600) ex. Courtaulds

6047 polyacrylamides ex. Allied Colloids

FRS 3966 ex. Allied Colloids

Jaguar C162 Meyhall

Polyethylene oxide (WSRN 80) ex. Union Carbide

Polyvinylpyrrolidone ex. PolySciences Polyvinylpyrrolidone had a molecular weight of about 386,000.

Example 1a-e

Comparison with cationic polymers

0.25 rng cm- ² (based on non-volatile substances) of contamination was deposited on the test surface of DECAMEL (RTM ex. Formica) with an A4 area by spraying. The contamination included 1% by weight glycerol tripalmitate, 0.5% by weight glycerol trioleate, 0.5% by weight kaolin, 0.2% by weight liquid paraffin, 0.1% by weight palmitic acid, 0.02% by weight carbon black in methyl alcohol. The soiling was aged for 24 hours at room temperature prior to purification.

The effort used to remove contamination from the test surface using cellulose sponge was measured. The formulations included a nonionic surfactant and water with or without a polymer. The surfactant used was Imbentin 91-35 OFA (TM) (C9-C11 alkyl, 3 to 5 EO alkyl ethoxylate ex. KLB). Illustrative polymers of the present invention were polyacrylic acid (ex. BDH) having an average molecular weight of 230000. The cationic polymer used in the Comparative Examples was Polymer JR-400 (TM: ex. Union Carbide) and had an average molecular weight of 40000. in Table 1, together with the effort required for the cleaning operation.

The results shown are geometric means from eight repeated experiments. To eliminate day-to-day variability due to differences in pollution levels, the data were normalized so that the effort required to clean DECAMEL tiles with the same polymer-free mixture was constant.

From the results given under the designation origin, it can be seen that the compositions of the invention have improved cleaning performance over Comparative Example 1a, where no polymer was present. This improvement is statistically significant with a confidence level of 95%.

In order to investigate the effectiveness of repeated contamination, DECAMEL plates were re-contaminated and re-cleaned using the same contamination and the same cleaning procedure. The cleaning results for the first and second re-cleaning cycles are given the same (2) and the same (3).

These results show a significant effect of the presence of the polymer. For compositions that did not contain a polymer (see Example 1a), the desired effort in subsequent purification cycles remains essentially constant. It can be seen that significantly less effort is required when surfaces are cleaned using polymer-containing compositions and are subsequently re-cleaned with the same composition.

The results given under the designation normal (4) are the results obtained by subsequent cleaning of the test surfaces used in Examples 1a to 1e with the composition used in Example 1a (i.e. the surfactant itself). This suggests that the benefit of the present invention persisted even when the test surfaces were cleaned with a conventional surfactant-only composition.

It should be noted that the initial cleaning benefits of the polymers of this invention (Examples 1c and 1e) are comparable unless they are directly slightly better than the cleaning performance achieved with a quaternized polymer (as used in Comparative Examples 1b and 1d).

Example 2d to 2g

Effect of polymer content level

Example 1 was repeated using the formulations shown in Table 2: except that the polyacrylic acid used was VERSICOL E1 (RTM) (ex. Allied Colloids: molar mass 250000). Efforts to clean DECAMEL (RTM) tiles are expressed in a logarithmic manner (basis 10) of the effort required. The examples were repeated with and without polymer and with different surfactant concentrations. Values shown are means of four replicates.

Table 1

la lb lc ld le Imbentin 10% 10% 10% 10% 10% JR Polymer - 0.25% - 1% - Polyacrylic acid (mol.hm. 230000) 0.25 1% Water up to 100% pH 4.2 4.4 3.7 4.6 3.3 beginning 1 0.29 0.24 0.36 0.25 Same (2) 1 0.11 0.15 0.12 0.14 Same (3) 1 0.05 0.06 0.06 0.06 normally 1 0.18 0.18 0.17 0.21

Results Starts were obtained using mixtures with polymer. Results Normal (1) was obtained by purification using mixtures according to the specification, but without polymer.

The same (2) values were obtained by re-cleaning the tiles initially cleaned with the polymer-containing composition to obtain the results listed under Origin (1), using the same composition as when the tiles were cleaned for the first time. The values labeled Normal (2) were obtained by cleaning the soiled reclaimed tiles from Normal (1) with a polymer-free composition having the same surfactant level.

Normal (3-5) values were obtained by cleaning tiles initially cleaned with a polymer-containing composition (to obtain results of the same (2)) with a polymer-free composition. The same level of surfactant (7% by weight: IMBENTIN) was used in all re-cleanings in the Normal (3-5) series.

Table 2

2d 2e 2f ² S Imbentin 16% 8% 4% 2% Polyacrylic acid (moLhm. 250000) 1% 0,5% 035% 0,15% Water up to 100% Log of the required initial effort Poäatok (l) 236 2.38 2.69 3.35 Normal (1) 237 3.04 3.43 Same (2) 2.18 2.14 2.18 2.80 Noimálne (2) without Significant Normal (D reduction from Re-cleaning "Rovnaké®" without polymént Normálnc (3) 2.17 1.98 1.99 2.02 Notmálne (4) 2.86 2.92 2.90 2.83 Notmálne (5) 3.02 3.04 2.99 3.03

From the results, it can be seen that the presence of the polymer had a primary cleaning benefit, i. j. less cleaning effort is required in the presence of the polymer than in its absence (compare Normal (1) to Initial (1). The magnitude of this effect increases considerably at low surfactant concentrations. This is believed to be due to excellent primary cleaning In Example 2g, it has proved impossible to clean the tiles using reasonable efforts using a low level of surfactant in the absence of the polymer.

It can also be seen that the effect of the polymer persists in subsequent cleaning cycles, but the effect decreases as the number of cycles increases.

Significantly low levels of polymer and surfactant content show a slight increase in secondary cleaning performance over higher levels. Thus, compositions containing low levels of surfactant and polymer clean at least as well as compositions containing higher levels of the following ingredients: compare 2d to 2f, in which fourfold levels of surfactant and polymer are present, and the same effort is required to clean the tiles. Polymer-free compositions do not clean when only low levels of surfactant are present. It has also been found that compositions which do not contain polymer do not reduce the desired effort on reuse.

Examples 2h to 21

Comparison of commercial hard surface cleaners

Examples 2h to 21 compare the effort required using highly diluted solutions of the products listed in Table 2c. Mixtures are diluted to typical floor cleaning dilutions as recommended by the manufacturers (approx. 3 g ^-1 ) ·

An exemplary embodiment of the invention is: 28% by weight of IMBENTIN, 2% by weight of polyacrylic acid (250000: VERSICOL Ell (RTM), ex. Allied Colloids). The composition of the comparative example using a nonionic surfactant alone omits the polymer.

Results of the percentage removal of contamination from the hydrophobic surface, determined by the standard colorimetric method, after 40 strokes, were obtained using an SHEEN-type in-line scrubber (RTM) using a pressure of 80 g.cn &^lt; ^{2 &gt};. The surface was DECAMEL (RTM) and precleaned with 0.061 mg.cm < ^{2 > of} contamination (based on nonvolatiles). Purification was performed with a cellulose sponge pre-impregnated with a suitable cleaning solution.

The percentage of soil removal from the hydrophilic surface was determined using the same soil applied to ceramic floor tiles, under identical conditions but with a single cleaning stroke.

Both groups of experiments were performed in three series with pollution type:

(a) 1% by weight of glycerol tripalmitate, 0,5% by weight of glycerol trioleanum, 0,5% by weight of kaolin, 0,2% by weight of liquid paraffin, 0,1% by weight of palmitic acid, 0,02% by weight of carbon black in methyl alcohol (ie 80: 20 fat: particles)

(b) as (a) with 50:50 fat: particles, and

c) as (a) with 20:80 fat: particles.

The use of these three model types of contamination and two surfaces illustrates the effectiveness of mixtures in practice. Three replicates were performed, each with three types of pollution and mean values from all nine measurements, such as 6

2806 correlated in the table were taken as indicative efficacy in practice.

Table 3

Example make DECAMEL ceramics 2h solution 65% 47% 2i Non-ionic PAL itself 58% 35% 2, j AJAX COMPACT 45% 30% 2k ULTRA FLASH (RTM) 40% 12% 21 FLASH LIQUID 28% 8%

From these results it can be seen that an embodiment of the invention significantly outperforms the comparative examples under the conditions mentioned.

In further experiments it was found that the embodiment used in Example 2h gave less residue and increased gloss (as determined by gloss measurement) than the comparative compositions of Examples 2i to 21 on black ceramic tiles.

Example 3

Anionic Surfactant / Anionic Polymer (Comparative Example)

Example 1 was repeated using simplified formulations consisting only of an anionic surfactant in water with or without an anionic or cationic polymer. The surfactant used was the magnesium salt of PAS. The anionic polymer was polyacrylic acid as in Example 1. The cationic polymer was Polymer JR as used in Example 1. The compositions are shown in Table 4, together with the effort required in the purification operation as mentioned in Example 1. The figures are geometric diameters from Eight replicate experiments normalized to present data when polymer-free mixtures always require the same cleaning effort.

Initial data on cleaning performance is given under Start (1). It can be seen that the polymer-containing compositions (3b to 3e) have insignificant primary cleaning benefits, but still more generally it is more difficult to clean the surface with an anionic or cationic polymer-containing surfactant than a similar polymer-free composition: e.g. see that for polymer-containing compositions, about two and a half times the initial cleaning effort was required compared to compositions without polymer.

To investigate re-contamination efficiency, DECAMEL plates were re-contaminated and re-cleaned using the same procedure. The cleaning results for the first and second re-cleaning cycles are shown as the same (2) and the same (3). These results show a generally negative effect believed to be due to the presence of an anionic polymer and a surfactant system of the same charge type.

The results reported as normal (4) '' are the results obtained by subsequent cleaning of the test surfaces used in Examples 3a to 3e with the mixture used in Example 3a, t. j. purification only with a surfactant (essentially a conventional mixture) in the absence of a polymer. This suggests that the negative effect of anionic polymers persisted when the test surfaces were cleaned with a conventional mixture of surfactant only. These results also show that the cationic polymers have a secondary cleaning benefit which is not seen with anionic polymers in the presence of an anionic surfactant.

Table 4

3a 3b 3c 3d 3e Magnesium PAS 5% 5% 5% 5% 5% JR Polymer - 0.25% - 1% - Polyacrylic acid - - 0.25 - 1% Water up to 100% pH 6.5 5.5 3.4 5.3 3.0 Start) 1) 1 1.18 2.42 1 1.18 Same (2) 1 0.20 2.10 0.18 1.10 Same (3) 1 0.15 2.01 0.16 0.90 Normal (4) 1 0.22 1.47 0.22 1.26

Similar experiments were performed with a cationic polymer (Polymer JR) and a cationic surfactant (tetradecyltrimethylammonium hydrogen sulfate). No effect was recognized. The absence of effect is believed to be due to the fact that the surfactant and the polymer have the same charge and consequently the inability of the surfactant and the polymer to form a complex.

Example 4

Comparison with other polymers

Additional series of experiments were performed using the materials listed in Table 5. Simplified preparations consisting of nonionic surface

Table 5

beginning repeated cleaning Maleic anhydride-acrylic acid copolymers 4a Sokolan CP12 TM 24 10 + 4b Sokolan CP13 TM 32 17 · ^; · methyl vinyl ether 4cGantrezAN119 (TM) 25 8 4d Gantrez ANI 70 (TM) 34 12 styrene 4e Scripset 520 29 9 ethylene 4ΓΕΜΑ31 22 11 Carboxylate polymer 4g SCMC 48 22 Cationic polymers Polyacrylamides 4h 6047A 34 21 4i 6047B 042 26 4j 6047C 47 23 4k 6047D 82 16 41FRS 3966 80 24 Modified Guar JaguarC162 54 22 Nonionic polymers 4n Polyethylene oxide 29 49 4o Polyvinylpyrrolidone 37 43

active substance (10% by weight) and water with and without polymer. The surfactant used was

IMBENTIN 91-35 OFA (C9 to C11 alkyl, 3 to 5 EO alkyl ethoxylate). The polymers used are listed in the table and were present at a level of 0.5% by weight.

The results were normalized so that the required initial cleaning effort with surfactant alone7

2806% was 100%. The benefit of repeated cleaning was evaluated by cleaning surfaces with a 7.5% aqueous solution of nonionic surfactant alone and measuring the desired effort: again, the results were normalized considering 100% cleaning effort, effort for surfactant alone.

These results are presented in graphical form in Figure 2. In this figure, primary (initial) and secondary (repetitive) efficiency are plotted on separate axes. The reference to the data in Figure 2 is by means of coordinates.

Examples of non-ionic polymers such as those disclosed in GB 1534722, such as the coating agents PO (49.29) and PVP (43.37), have a particularly weak re-cleaning effect, although the primary cleaning efficiency is good.

Cationic polymers have some benefits in both primary and secondary purification, although the trend suggests that two factors have the opposite relationship, i.e., better purification in one situation is generally associated with poor performance in another: compare polyacrylamide to (82,16) ) apolyacrylamide to (42.26).

It is clear from Figure 2 that a greater benefit is obtained with the anionic polymers of the present invention, and in particular with maleic anhydride copolymers, preferably those of styrene, acrylic acid, methyl vinyl ether and ethylene. The results show that, with the exception of carboxymethylcellulose (22.48) and Sokolan CP13 (TM) (17.32), anionic polymers generally had improved performance over all comparative examples in both primary and secondary purification.

Example 5

Effect of polymer concentration

Figure 1 shows a graph of the effect of polymer concentration (230000 ex. BDH) on cleaning effort and anti-fouling benefit. All mixtures were at a natural pH of 4 and contained a surfactant (Imbentin 91-35 OFA: C 9 to C 11 alkyl, 3 to 5 EO alkyl ethoxylate) at a level of 10 wt%. The cleaning and anti-fouling effects were evaluated as in Example 4.

The figure illustrates that with the compositions of the invention, the initial (primary) cleaning effect becomes significant even at very low polymer levels and persists as the polymer level increases. Anti-fouling effects become apparent at levels of about 0.2% by weight of the polymer and continue to persist. This is consistent with the results obtained in Example 2d to 2 g.

Example 6

Effect of pH

Table 6 shows the effect of pH on the compositions of the present invention containing 0.5% by weight polyacrylic acid polymer (230000, ex. BDH) and comparative compositions that do not contain the polymer. All mixtures contained a surfactant (Imbentin 91-35 OFA: C9-C11 alkyl, 3-5 EO alkyl ethoxylate) at a level of 10% by weight. The pH was adjusted by the presence of NaOH. The cleaning and anti-fouling effects were evaluated as in Example 4. The cleaning effort is expressed as the logarithm (base 10) of the desired effort.

Table 6

primary effort secondary effort PH with polymer- rom without polymer with a polymer without polymer 6a 3.5 2.25 2.45 2.25 2.72 6b 5.0 2.30 2.45 2.30 2.72 6c 7.0 2.50 2.45 2.85 2.72 6d 9.0 2.70 2.45 2.72 2.72

It can be seen that at a low pH especially below 7.0, there is a significant reduction in the required primary and secondary cleaning efforts for polymer-containing systems over compositions containing only a nonionic surfactant.

Claims (6)

PATENT CLAIMS Liquid hard surface cleaning composition having a pH of 3 to 7, characterized in that it comprises: (a) 1 to 30% by weight of non-ionic surfactant; b) 0.005 to 3% by weight of a water-soluble anionic polymer having an average molecular weight of less than 1000000, said polymer being free of quaternary ammonium groups, wherein the ratio of polymer: nonionic surfactant is 0.1: 1 or less. A composition according to claim 1, characterized in that it comprises 0.2 to 2.0% by weight of the anionic polymer. The composition of claim 1, wherein the anionic polymer is selected from the group consisting of polymers of acrylic acid or methacrylic acid or maleic anhydride, a copolymer of one or more of these, either with each other or with other monomers, and mixtures thereof. 4. The composition of claim 3 wherein the polymer is selected from the group consisting of polyacrylic acid, polymaleic anhydride, and a copolymer of one of said materials with ethylene, styrene, and methyl vinyl ether. 5. The composition of claim 1 wherein the molecular weight of the polymer exceeds 100,000. A composition according to claim 1, characterized in that it comprises max. 33% by weight of anionic surfactant of the total detergent active.