WO1997043369A1

WO1997043369A1 - Insect-repellent compositions comprising antimicrobial agents and nonionic surfactant

Info

Publication number: WO1997043369A1
Application number: PCT/EP1997/002495
Authority: WO
Inventors: Alexander Allan; Timothy David Finch; Christopher Maddison; Kenneth Leslie Rabone; Martin Sharples
Original assignee: Unilever Plc; Unilever N.V.
Priority date: 1996-05-09
Filing date: 1997-04-29
Publication date: 1997-11-20
Also published as: IN183457B; AU2955897A; ZA973929B; GB9609668D0

Abstract

The present invention provides a hard surface cleaning composition comprising: a) a nonionic surfactant, b) 0.1-15 wt.% on product of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof., and c) an insect repellent. It is believed that the synergy between the selected antimicrobial agent and the nonionic surfactant provides an effective antimicrobial action without requiring the presence of strongly reactive species which would otherwise react chemically with the insect repellent material.

Description

insect-repellent Compoaitiona Comprising Antimicrobial Aαents and Nonionic Surfactant

Technical Field:

The present invention relates to disinfecting and insect- repellent compositions comprising nonionic surfactant .

Background of the Invention;

Cleaning compositions generally comprise one or more surfactants, and, optionally, one or more hygiene agents. These compositions function to keep surfaces free from microbial contamination in two ways, firstly by removing soils and secondly by killing bacteria and other microbes which live in an upon these soils.

Typical surfactants are selected from anionic, nonionic, amphoteric and cationic surfactants. With nonionics being very commonly used due to their effectiveness on fatty soils and low foaming. Of these surfactants, nonionics show low biocidal activity, whereas certain anionic, cationic and amphoteric surfactants show biocidal activity under specific conditions of, for example, pH and concentration.

Known hygiene agents in common use include, strong acids, alkali's, phenolics, peracids and hypohalides. These are generally highly reactive species which exhibit this reactivity in terms of one or more of, short shelf life, toxic, corrosive and irritant properties. In general, these components are required at relatively high levels in formulations.

Other less reactive hygiene agents, such as 2 , 4, 4 ' -trichloro- 2 ' -hydroxy diphenyl ether (available in the marketplace as IRGASAN [RTM] ) , are effective at relatively low concentrations but are more expensive than simpler species.

In addition to the above, many organic acids, including benzoic, salicylic and sorbic are known as preservatives in cosmetics and some foods. These preservatives generally show lower biocidal activity than the above-mentioned hygiene agents when used at the same level.

A hygiene agent is preferably an agent which shows a 100,000 fold or better reduction in the number of viable microorganisms in a specified culture when used at a level of around 0.5%. This is generally known as a 'log 5 kill' . Of the organic acids mentioned above, salicylic acid is generally regarded as the most effective biocide against common bacteria, but it's activity falls far short of that required of a hygiene agent.

Many hygiene agents exhibit their activity over the relatively short term and do not provide a residual anti¬ microbial effect. Thus a surface which has been treated with these agents will only remain sterile until microbes are re- introduced. Insects are known carriers of disease-causing bacteria and it is an object of the present invention to provide a composition which not only has a cleaning and hygiene function but which also repels insects so as to prevent re-contammation of a surface.

It is known to incorporate insect repellents in cleaning compositions. GB 2056859 (published 1981) discloses compositions consisting essentially of the glass cleaner AJAX VITRE and an insecticide. PCT/US85/01944 (published 1986) teaches that mono-alkyl phosphate insect repellents can be added to a detergent and used to wash objects and animals and thereafter will have a repellent effect which persists for some time. EP 0367257 discloses insect repellents for incorporation into detergents since they are substantive for soft surfaces (eg humans, animals, laundry or rugs) and hard surfaces. The amount of the specific compound deposited on the washed surface is 0.2-10 (pref 0.5-2)g/scrm. They can also be formulated as repellant sprays etc, as dispersions or solns in liquid media. The compounds are said to be especially effective against cockroaches but can also repel spiders, ticks, mites, flies, ants, etc. EP 0619363 relates to aqueous liquid detergents which comprise a surfactant, at least 50% water and an effective amount of an insect repellent material. The compositions are free of insecticides. Amongst the insect-repellents mentioned are materials which are known insect repellents per se and also perfumes. Other materials can be present in the composition and these include soil release promoting agents, which may be polymers .

Insect repellents are chemically sensitive to oxidising agents such as hypochlorite and other common hygiene agents such as peroxy-compounds . As the presence of insects is commonly associated with the presence of bacteria-harbouring soils there is a need for an effective cleaning composition which both repels insects and has a microbicidal effect.

Having regard to the elaboration of the present invention as set out below it can be seen that a number of compositions which are related to the compositions of the invention are known. These are described as follows.

GB 718050 (Miles Labs: 1951) relates to a germicidal, fungicidal and deodorant composition for topical application to skin which comprises fungicide, ethanol, menthol, camphor or other essential oils and chlorothymol and a nonionic surfactant. The levels of the surfactants in the compositions disclosed are so low (around 0.35%wt) that they would not provide an effective cleaning composition for hard surfaces.

GB 431344 (ICI: 1935) relates to a treatment for protecting wood against fungus which comprises in addition to a fungicide, surfactant and an essential oil. The levels of surfactant in this composition is again far too low for it to be considered as a hard surface cleaning composition.

JP 89263738 (Nitto Denko Corp: 1989) relates to a medical composition which comprises nonionic surfactant, limonene and a medicated component which can be sodium salicylate.

Brief Description of the invention:

Accordingly the present invention provides a hard surface cleaning composition comprising: a) at least 0.5% of a nonionic surfactant, b) 0.1-15%wt on product of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof, and, c) an insect repellent.

We have determined that the antimicrobial agents described above, which exhibit a synergy with the nonionic surfactant, are compatible with insect repellents. Without wishing to limit the invention by any theory of operation it is believed that the synergy between the selected antimicrobial agent and the nonionic surfactant provides an effective antimicrobial action without requiring the presence of strongly reactive species which would otherwise react chemically with the insect repellent material. Thus the compositions provide both a hygiene and a cleaning benefit while also providing an effective insect-repellency which assists in preventing re- contamination of the surface by microbes carried on insect vectors.

The invention also extends to a method for cleaning hard surfaces and repelling insects therefrom which comprises the step of treating the surface with a composition comprising: a) at least 0.5% of a nonionic surfactant, b) 0.1-15%wt on product of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof, and, c) an insect repellent.

Detailed Description of the invention:

Surfactants:

Nonionic surfactants are an essential component of the compositions according to the invention. The surfactants are preferably, alkoxylated alcohols or amine oxides. Alkoxylated alcohols are preferred as surfactants, with ethoxylated alcohols being the most preferred.

Suitable nonionic detergent active compounds can be broadly described as compounds produced by the condensation of alkylene oxide groups, which 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 particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements. Particular examples include the condensation product of aliphatic alcohols having from 8 to 22 carbon atoms in either straight or branched chain configuration with ethylene oxide, such as a coconut oil ethylene oxide condensate having from 1 to 15 moles of ethylene oxide per mole of coconut alcohol; condensates of alkylphenols whose alkyl group contains from 6 to 12 carbon atoms with 1 to 25 moles of ethylene oxide per mole of alkylphenol.

Particularly preferred nonionic surfactants include the condensation products of C₈-C₁₈ alcohols with 2-12 moles of ethylene oxide. The most preferred alkoxylated alcohol nonionic surfactants are ethoxylated alcohols having a chain length of C,-C_n and an EO value of at least 5 but less than 10. Particularly preferred nonionic surfactants include the condensation products of C₁₀ alcohols with 5-8 moles of ethylene oxide.

The preferred ethoxylated alcohols have a calculated HLB of 10-16. While mixtures of nonionic surfactants can be used it is preferred to use a single commercially available surfactant .

The amount of nonionic detergent active to be employed in the composition of the invention will generally be from 0.5 to

30%wt, preferably from 1 to 20%wt, and most preferably from 2 to 7%wt for non-concentrated products. Concentrated products will generally have 7-20%wt nonionic surfactant present, whereas dilute products suitable for spraying will generally have 0.5-10%wt nonionic surfactant present.

Alternative preferred surfactants include coconut ethanolamide and ethanolamine ethoxylates, and C₁₂ amine oxide. It is preferred that the compositions of the present invention are essentially free of anionic surfactant. The amount of anionic detergent active to be employed in the detergent composition of this invention will generally be from 0.5 to 25%wt (on total active) , preferably less than 10%wt (on total active) most preferably less than 5%wt.

Antimicrobial Agents:

Typical levels of the antimicrobial agent in formulations range from 0.01 to 8%, with levels of 0.05-4wt%, particularly around 2% being preferred for normal compositions and up to two or four times that concentration being present in so called, concentrated products. For sprayable products the concentration of the antimicrobial agent will be in the range 0.05-0.5%wt .

In general, whatever the strength of the product the ratio of the nonionic surfactant to the antimicrobial agent will preferably be in the range 50:1 to >1:1, more preferably 30:1 to >1: 1 i.e. an excess of nonionic will be present.

The term 'benzoic acid derivatives' , includes benzoic acid and derivatives thereof. In particular it includes ortho- hydroxy benzoic acid derivatives including salicylic acid. Surprisingly, we have determined that the presence of a benzoic acid derivative also improves the cleaning performance of the compositions. Benzoic acid derivatives are the preferred antimicrobials.

The preferred antimicrobial agent is salicylic acid, which gives better hygiene results than benzoic and shows a very marked improvement as compared with sorbic acid. Alternative acids are the polyhydroxyl carboxylic acids in which at least one of the hydroxyl groups is ortho- to the carboxylic acid group. The remaining hydroxyl group or groups can be in the remaining ortho-, para- or meta- configurations. The polyhydroxyl carboxylic acids exhibit the same synergy as the mono hydroxylic acid derivative (salicylic acid) but are believed to be less irritant.

It was also found that in the presence of nonionic surfactant, salicylic acid derivatives methylated at positions 3-6 exhibit an additional antimicrobial action over that obtained with salicylic acid. This was particularly true for gram positive bacteria and yeasts. In contrast hydroxylation at these sites was found to decrease the synergistic effect.

The preferred alkyl substituted ortho-hydroxy aromatic carboxylic acid is of the general formula:

R₁-C₆H₃ (OH) (COOH)

wherein R_j is C_{j 12} alkyl, and the hydroxyl group is ortho to the carboxyl group.

Usefully, the alkyl substituted ortho-hydroxy aromatic carboxylic acids are substituted at the 3, 4 or 5-position, relative to the carboxyl group. Preferred chain lengths for the alkyl group are C_]-6, with methyl substituted acids being particularly preferred. Particularly preferred acids are 2 - hydroxy 5-methyl benzoic acid, 2-hydroxy 4-methyl benzoic acid and 2-hydroxy 3-methyl benzoic acid.

While the alkyl substituted ortho-hydroxy aromatic carboxylic acid mentioned above is the most preferred antimicrobial agent, dicarboxylic acids can be used in addition to or instead of them.

It is envisaged that suitable dicarboxylic acids include succinic acid, malic acid and ascorbic acid.

Advantageously, the dicarboxylic acid mixture present in the formulation include adipic, glutaric and succinic acid and mixtures thereof. The mixtures are preferred as these are commercially available. Typical mixtures which can be found in the marketplace comprise 30-35% adipic acid, 45-50% glutaric acid and 10-18% succinic acid. Such a mixture is available in the marketplace as Sokalan DCS (TM, ex. BASF) . Another suitable mixture is available as Radimix (TM, ex. Radici) . The use of essentially pure acids is not excluded but these have limited commercial availability. These compositions have the further advantage that they assist in the removal of limescale and other calcinareous deposits, while these deposits are themselves unsightly they also can provide a haven for microbes.

Mixtures of benzoic acid derivatives and the dicarboxylics are preferred to the use of the dicarboxylic acids as the sole antimicrobial component.

insect Repellents:

An effective level of insect repellent is an essential component of the compositions of the present invention,

Particularly suitable insect repellents include essential oils such as those of genus Mentha, particularly Mentha arvensis, mentha piperita, Mentha spicata and Mentha cardica; Lemongrass East Indian oil. Lemon oil, Citronella, Cedarwood and Pine oil; terpenoids, particularly limonene, carvone, cineole, linalool, Gum Camphor, citronellal, alpha and beta terpenol, fencholic acid, borneol, iso borneol, bornyl acetate and iso bornyl acetate.

The most preferred insect repellents are the terpenoids, particularly limonene. Many of the terpenoids are not unpleasant-smelling to humans and consequently the insect repellent material while fulfilling its primary function also can have the secondary function of lending a pleasing smell to the composition.

The level of insect repellent required will vary with the nature of the material used. For essential oils and terpenoids, preferred levels are 0.1-5% on product.

It is preferred that the ratio of surfactant to insect repellent does not exceed 10:lwt% and more preferably that the ratio of surfactant to insect repellent falls in the range 8-2:1.

It is preferred that the ratio of insect repellent to polymer is in the range less than 5:1 but more than 0.5:1. We have found that ratios of 4:1 of a perfume containing 54% insect repellent to polymer were effective.

Surprisingly, it has been found that the presence of the insect repellent perfume acts synergistically with the antimicrobial agent, particularly when this is a benzoic acid derivative, allowing effective disinfection over a broader pH range.

Polymers:

Polymers are an optional component of compositions according to the present invention. It is preferable that these polymers are carboxylate polymers. In the context of the present invention a carboxylate polymer is one formed from monomers which comprise a carboxy-functional group. This group of polymers excludes polymers such as silicone oils and mineral oils.

The preferred polymers in embodiments of the present invention are polymers of acrylic or methacrylic acid or maleic anhydride, or a co-polymer of one or more of the same either together or with other monomers. Particularly suitable polymers include polyacrylic acid, polymaleic anhydride and copolymers of either of the aforementioned with ethylene, styrene and methyl vinyl ether.

The most preferred polymers are maleic anhydride co-polymers, 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 in excess of 100,000. The molecular weight of the polymer is preferably below 1,000,000 Dalton.

Typically, the compositions comprise at least 0.01wt% polymer, on product. Preferably the level of polymer is 0.05-5.0wt%. More preferably 0.1-4.0wt% of polymer is present. However, for very concentrated products which are diluted prior to use, the initial polymer level can be as high as 5%wt .

Without wishing to limit the invention by reference to any theory of operation, it is believed that, in the compositions of the invention, the polymer assists in transporting the insect repellent to the surface and maintaining the repellent on the surface during the cleaning operation. Consequently, despite the presence of surfactants in the compositions of the invention and the oily nature of many insect repellents, the insect repellent is not removed from the surface by the surfactant.

We have also determined that in the presence of polymer the insect repellent is released from the surface over a prolonged period of time. This is advantageous as the reinfection of the surface through insect vectors is further delayed as the period over which insects are effectively repelled is extended.

A further advantage of the polymer is believed to be a reduction of the energy required to clean the surface both in initial (primary) and in second and subsequent (secondary ) cleaning operations. This is believed to be due to the deposition of components of the composition at the surface which increase the surfactant concentration at the surface and form a protective film which retards the attachment of soils to the surface when the surface is resoiled.

Perfumes:

The compositions of the present invention preferably contain perfume components other than the insect repellent perfume components mentioned above. Typical levels being 0.1-5%wt on product. Advantageously, perfume components are deposited at the surface in the same manner as the insect repellent components and consequently released over a prolonged period of time to give a persistent pleasant smell to surfaces which have been cleaned with the compositions according to the invention.

Fully formulated compositions according to the invention therefore effectively remove soil and kill bacteria while depositing both a surface-protective polymer and a long- lasting, pleasant smelling, insect repellent on the surface, to prevent both resoiling and re-contamination of the surface.

In view of the components used in its manufacture and in the interests of overall perfume balance, is advantageous to employ a single insect-repellent and perfuming component in compositions according to the invention. A suitable insect repellent, pleasant smelling perfume is commercially available as 'Stay Away 2001' (TM) ex. Givaudan Roure. This will generally be used in compositions according to the invention at levels of 0.5-3%wt.

Minors:

The composition according to the invention can contain other minor, unessential ingredients which aid in their cleaning performance and maintain the physical and chemical stability of the product.

For example, the composition can contain detergent builders. In general, the builder, when employed, preferably will form from 0.1 to 25% by weight of the composition.

Metal ion sequestrants such as ethylene-diamine-tetra- acetates, amino-polyphosphonates (such as those in the DEQUEST^R range) and phosphates and a wide variety of other poly-functional organic acids and salts, can also optionally be employed.

Citrate is particularly preferred as this functions as a buffer maintaining the composition at a pH in the range 3-5 on dilution. Typical levels of citrate range from 0.5-5%, with higher levels of 5-10% being used in concentrates and lower levels of 0.1-1% being used in sprayable products. Citric can be replaced by other suitable buffering agents to maintain the pH in this range. Citric is preferred for environmental reasons and a lack of residues.

Hydrotropes, are useful optional components. It is believed that the use of hydrotropes enables the cloud point of the compositions to be raised without requiring the addition of anionic surfactants. Preferably the formations according to the invention are free of anionics, or contain low levels of anionics, i.e. less than 50% of the level of the betaine.

Suitable hydrotropes include, alkali metal toluene sulphonates, urea, alkali metal xylene and cumene sulphonates, short chain, preferably C₂-C₅ alcohols and glycols. Preferred amongst these hydrotropes are the sulphonates, particularly the cumene and toluene sulphonates.

Typical levels of hydrotrope range from 0-5% for the sulphonates. Correspondingly higher levels of urea and alcohols are required. Hydrotropes are not required for dilute products.

Compositions according to the invention can also contain, in addition to the ingredients already mentioned, various other optional ingredients such as, solvents, colourants, optical brighteners, soil suspending agents, detersive enzymes, compatible bleaching agents (such as reducing bleaches) , gel- control agents, freeze-thaw stabilisers, further bactericides, additional perfume components and opacifiers.

CH:

Preferably, the composition has a pH of 3.2-4.5. It is believed that the above pH 4.5 the hygiene benefit of the compositions is less pronounced and below pH 3.0 surface damage may occur.

The most preferred pH is around 3.5-3.8. Compositions having a pH of less than 3.0 will damage enamel surfaces.

Compositions having a pH significantly above 4.5 will show reduced kill against micro-organisms.

For dilutable products, in typical waters from hard water areas, citrate at a level of 3.5% will be sufficient to reduce the pH on addition of the product of the present invention at 3.3g/l to a pH below 4.0. For sprayable products less steps need be taken to maintain the pH. It is believed that the relatively low pH of the composition is important in achieving both the cleaning and the antimicrobial synergies which are exhibited by the products according to the invention.

Preferred Compositions:

The effectiveness of the compositions varies with the ratio of the components present. As mentioned above it is preferred that the ratio of surfactant to insect repellent does not exceed 10:lwt%.

Particularly preferred compositions according to the invention comprise: a) l-10%wt of an ethoxylated alcohol, b) 0.01 to 8%wt of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof, and, c) 0.2-4%wt of a terpenoid insect repellent material More particularly preferred compositions according to the invention comprise: a) l-10%wt of an ethoxylated alcohol, b) 0.01 to 8%wt of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof, c) 0.2-4%wt of a terpenoid insect repellent material, and, d) 0.01-5.0wt% of a carboxylate polymer.

The most preferable compositions according to the invention have a pH of 3.2-4.5 and comprise: a) l-10%wt of an C8-C12 3-8EO ethoxylated alcohol nonionic surfactant, b) 0.01 to 8%wt a 2-hydroxy benzoic acid derivative, preferably salicylic acid, c) 0.2-4%wt of a terpenoid insect repellent material said insect repellent material comprising limonene d) 0.01-5.0wt% of a polyacrylic acid polymer, e) 0.1-2% of a betaine or amine oxide.

In the presence of nonionic surfactant, polymer, antimicrobial agent and the insect repellent a series of synergistic interactions are believed to take place which greatly enhance the effectiveness of this simple composition. The synergy between the selected antimicrobial agent and the nonionic surfactant provides an effective antimicrobial action without requiring the presence of strongly reactive species which would otherwise react chemically with the insect repellent material. The polymer and the nonionic surfactant interact to give both a reduced effort requirement for both primary and secondary cleaning and promote the deposition and retention of the insect repellent at the surface. The insect repellent and the antimicrobial agent are believed to interact so as to improve the antimicrobial activity over the pH range of the product.

In order that the invention can be further understood it will be explained hereafter with reference to the following non- limiting examples.

Examples:

Example 1: insect Repellency

In the following examples components are identified as follows (Table 1) :

Table 1:

Nonionic 5% DOBANOL (TM) 91-5; ethoxylated alcohol,

CAPB* 1% Amonyl 380BA

Hydrotrope 2.96% Sodium Cumene Sulphonate,

Buffer 3.5% Citric Acid

Antimicrobial 2.0% Salicylic acid

Perfume 1.0% A perfume comprising at least 50% limonene *Coco-Amido Propyl Betaine

Compositions of examples were prepared by mixing the components in the proportions given above.

Experiments were performed in an 6.0 square meter tiled room of which half the floor, divided diagonally, was treated with 10ml the neat or dilute composition and half left untreated. The air in the room was changed four times an hour during the course of the experiment. Insects were introduced at the center of the room. Repellency is defined as the percentage of insects (thirty Blattella σermanica (German cockroaches) were used) which were in the untreated zone after the indicated time in minutes. As can be seen from the above a repellency of 50% indicates that the composition had no effect. Results are presented in Table 2 below for composition both with and without perfume. Example A is a composition without perfume applied neat, B is A diluted at 20g/l in water. C and D are neat and dilute compositions comprising perfume at 1% as indicated above.

Table 2 :

Time (min) A B C D

5 59 42 100 100

10 58 46 100 100

15 53 47 100 100

20 49 47 100 100

25 42 49 100 100

30 48 50 100 100

35 53 53 100 100

40 53 58 100 100

45 59 54 100 100

50 62 59 100 100

55 62 58 100 100

60 62 58 100 100

24hours 46 63 100 100

From the results in Table 2 it can be seen that the compositions A (neat, without perfume) and B (dilute, without perfume) had little or no effective insect repellency whereas the compositions C (neat, with perfume) and D (dilute, with perfume) both had very effective insect repellency during the 24 hour course of the experiment. As the 'perfume' components of the insect repellent material also lend a pleasant citrus smell to the compositions of the invention, these results indicate that the pleasant smell will be longer-lasting in the presence of the polymer. Example 2: Cleaning

In the following examples components are identified as follows (Table 3):

Table 3 :

Nonionic :Imbentin 91 35 OFA; ethoxylated alcohol,

CAPB* :Amonyl 380BA

Hydrotrope :Sodium Cumene Sulphonate,

Buffer :Citric Acid

Antimicrobial :Sodium Salicylate

Perfume :A perfume comprising at least 50% limonene

Polymer :Versicol Ell [TM] : polyacryic acid

*Coco-Amido Propyl Betaine

Compositions of examples were prepared by mixing the components in the proportions given below in Table 4. The cloud point of each formulation has been adjusted to 50 degrees C. using the hydrotrope (SCS) . The pH of each formulation was been adjusted to 3.5 using NaOH.

Table 4:

Formulation 1 2 3 4

Nonionic 5. .0 5. ,0 5. .0 5. .0

CAPB 1. .0 1. ,0 1. ,0 1. .0

Hydrotrope 3. .0 2. .9 1. .8 0. .9

Buffer 3. .5 3. .5 3. .5 3. ,5

Antimicrobial 2. .0 2. .0 0. .0 0. .0

Perfume 1, .0 1. .0 1. .0 1. ,0

Polymer 0.31 0.00 0.31 0.00

PH 3.5 3.5 3.5 3.5

Cloud Point 50.0 50.0 50.0 50.0 The results given in Table 5 below are in the form of the effort measured to clean A4 areas of model fatty kitchen soils.

Table 5 :

Formulation 1 2 3 4

Volume used (mis) 2.5 3.25 2.25 3.5

Effort [Nsec] 836 1288 990 1672

Non underscored samples are significantly different (95% confidence level) . Taking mean effort scores it can be seen that the effect of polymer inclusion is significant at 99.9%: mean effort without polymer is 1467 Nsec while with polymer the effort is reduced to 909 Nsec. The 2 polymer containing samples also require less product to achieve complete cleaning. The effect of salicylate is also significant at the 90% level: mean effort without the salicylate is 1287 Nsec while with salicylate the effort is reduced to 1037 Nsec.

From the results in Table 5 it can be seen that the presence of polymer and the benzoic acid derivative both improve the cleaning performance of the composition.

Example 3 : Hygiene

In example 3 the same formulations as used in example 2 were tested for their hygiene properties in a 96 well (8x12) microtitre plate, using a test related to the 'European Suspension Test ' .

lml of formulation was diluted into 14ml of water. 5ml of the diluted solution was added to 4ml of distilled water and 270 μl of the product dosed into one well of the microtitre plate. This was repeated for the remaining 7 formulations being tested on this plate. 8 wells were simultaneously inoculated with 30μl bacterial suspension using a multipipette and agitated. After a 5mins (+/-5secs) contact time 30μl samples were transferred into 270μl inactivation liquid (as used in examples 1 and 2) using a multipipette and mixed. After 5mins (+/-lmin) 30μ samples were serially diluted into 270μl of Ringers solution using a multipipette and mixed. TVC (total viable count) was determined by a spread plate method: plating out lOμl (in triplicate) onto TSA and incubating for 24 hours at 30 °C. The microbes used were S.aureus (Gram positive) and E.coli (Gram negative) . Four formulations were tested on two sequential days in triplicate (6 results per microbe per formulation) . The results are summarized below in Table 6 which gives log reductions in viable count and standard deviations of these results.

Table 6:

Formulation 1 2 3 4

Nonionic 5. .0 5. .0 5. .0 5. ,0

CAPB 1. .0 1. .0 1. .0 1. ,0

Hydrotrope 3. .0 2. .9 1. .8 0. .9

Buffer 3. .5 3. .5 3. .5 3. .5

Antimicrobial 2. .0 2. .0 0. .0 0. .0

Perfume 1. .0 1. .0 1. ,0 1. .0

Polymer 0.31 0.00 0.31 0.00 pH 3.5 3.5 3.5 3.5

Cloud Point 50.0 50.0 50.0 50.0 Log Reductions

S.aureus 9.0 8.2 3.4 3.3

(sd) (0.5) (1.1) (0.8) (0.9)

E.coli 8.3 7.8 3.7 3.4

(sd) (0.8) (1.1) (0.2) (0.3)

The results indicate that without the antimicrobial agents (in this instance salicylate), formulations could not achieve disinfectant status, that salicylate can make the formulations effective disinfectants and that the presence of polymer does not detract from the hygiene delivery against these organisms.

Example 4:

The fully formulated product according to Table 7 was prepared by mixing of the components listed in the proportions given.

Table 7

This product was found to be an effective, storage stable, hard surface cleaning composition. It is believed that the composition gives a reduction in effort both in primary and secondary cleaning, has a strong antimicrobial effect and provides both a persistent, pleasant perfume and persistent insect repellency.

Claims

SLKVAS.:

1. A hard surface cleaning composition comprising: a) at least 0.5% of a nonionic surfactant, b) 0.1-15%wt on product of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof. , and, c) an insect repellent.

2. Composition according to claim 1 wherein the nonionic surfactant is present at a level of 0.5-30%wt on total product and is the condensation products of C₈-C_ιe alcohols with 2-12 moles of ethylene oxide.

3. Composition according to claim 1 wherein a carboxylate polymer is present at a level of 0.01-5%wt on total product and the polymer is a polymer of acrylic or methacrylic acid or maleic anhydride, or a co-polymer of one or more of the same either together or with other monomers .

4. Composition according to claim 1 wherein the insect repellent is present at a level of 0.1-5% on product and is selected from the group comprising limonene, carvone, cineole, linalool, Gum Camphor, citronellal, alpha and beta terpenol, fencholic acid, borneol, iso borneol, bornyl acetate, iso bornyl acetate and mixtures thereof.

Composition according to claim 1 wherein the antimicrobial agent is an ortho-hydroxy benzoic acid derivative, preferably salicylic acid. 6. Composition according to claim 1 which comprises: a) l-10%wt of an ethoxylated alcohol, b) 0.01 to 8%wt of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof . , and, c) 0.2-4%wt of a terpenoid insect repellent material.

7) Composition according to claims 6 which comprises: a) l-10%wt of a C₃-C₁₈ ethoxylated alcohol with 2-12 moles of ethylene oxide, b) 0.01 to 8%wt of an antimicrobial agent selected from the group comprising: benzoic acid derivatives, dicarboxylic acids, and mixtures thereof, c) 0.2-4%wt of a terpenoid insect repellent material, and, d) 0.01-5.0wt% of a carboxylate polymer.

8) Composition according to claim 1 having a pH of 3.2-4.5 which comprises: a) l-10%wt of an C8-C12 3-8EO ethoxylated alcohol nonionic surfactant, b) 0.01 to 8%wt a 2-hydroxy benzoic acid derivative, c) 0.2-4%wt of a terpenoid insect repellent material, said material comprising limonene, , d) 0.01-5.0wt% of a polyacrylic acid polymer, e) 0.1-2% of a betaine or amine oxide.