WO2011064554A1 - Anti-microbial wipes - Google Patents

Abstract

The present invention provides an anti-microbial wipe comprising a substrate comprising from 1 to 100% by weight of a cellulosic material and incorporating a composition comprising (i) an anti-microbial component; (ii) a non-ionic surfactant; (iii) a polar solvent; and optionally (iv) a hydrophobic material; wherein the anti-microbial component (i) comprises (a) at least one quaternary ammonium compound of formula (A) R₁R₂R₃R₄N⁺X^-, wherein R₁, R₂, R₃ and R₄ represent, independently a substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, alkylaryl, arylalkyl, cycloalkyl, heterocyclyl or alkenyl group, and wherein the total number of carbon atoms in the groups R₁, R₂, R₃ and R₄ is at least 4; wherein the substituents for the groups R₁, R₂, R₃ and R₄ are selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, heterocyclyl, substituted heterocyclyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl, F, Cl, Br, I, -OR', -NR'R", -CF₃, -CN, -NO₂, -C₂R', - SR', -N₃, -C(=O)NR'R", -NR'C(=O) R", -C(=O)R', -C(=O)OR', -OC(=O)R', -O(CR'R")_rC(=O)R' -O(CR'R")_rNR"C(=O)R', -O(CR'R")_rNR"SO2R', -OC(=O)NR'R", -NR'C(=O)OR", -SO₂R', - SO₂NR'R", and -NR'SO₂R"; wherein R' and R" are individually hydrogen, C₁-C₈ alkyl, cycloalkyl, heterocyclyl, aryl, or arylalkyl, and r is an integer from 1 to 6, or R' and R" together form a cyclic functionality; wherein the term "substituted" as applied to alkyl, alkenyl, heterocyclyl, cycloalkyl, aryl, alkylaryl and arylalkyl refers to the substituents described above, starting with F and ending with -NR'SO₂R"; and wherein X^- is halide or sulphonate; and optionally (b) one or more additional anti-microbial agents, and wherein the composition is substantially free of anionic surfactant.

Description

ANTI-MICROB1AL WIPES

This invention relates to anti-microbial wipes which are designed for cleaning hard surfaces such as those found in home, office, institutional and hospital environments or the skin or fabric surfaces.

Microorganisms are known to present health hazards due to infection or contamination. When microorganisms are present on the hard surface or on skin, they can replicate rapidly to form colonies. The microbial colonies form a coating on the surface, which is known as a biofilm. Biofilms frequently consist of a number of different species of microorganisms which in turn can be more difficult to eradicate and thus more hazardous to health than individual microorganisms. Some microorganisms also produce polysaccharide coatings, which makes them more difficult to destroy. Many anti-microbial agents that can destroy microorganisms which are present in a wide range of environments such as medical, industrial, commercial, domestic and marine environments are known. Many of the known anti-microbial agents have previously been included in compositions for use in various applications and environments. For ease of use and consumer convenience it would be advantageous to provide wipes impregnated with an anti-microbial composition. While some antimicrobial wipes are known in the art, such as those described in WO02/50241 , EP-A-1153544 and US2006/0009369 it has hitherto been difficult to prepare highly effective biodegradable wipes which comprise cationic antimicrobial agents.

It is widely recognised that quaternary ammonium antimicrobials are incompatible with a wide range of anionic surfactant substances, forming salts that are often insoluble in the carrier medium and which have no, or greatly reduced, antimicrobial effectiveness. Similarly, it is known that cationic antimicrobial substances such as quaternary ammonium compounds and PHMB bind strongly to fibres that contain anionic binding sites, for example carboxyl as found in viscose and other processed cellulosic fibres. This binding of cationic antimicrobials may be used to produce wipes or cloths that are resistant to microbial growth on the cloth or wipe itself. However, by binding strongly to the fibres, the cationic antimicrobial is effectively removed from the supernatant liquid thus greatly reducing or eliminating the antimicrobial properties of the liquid. This is clearly disadvantageous when the intention is to produce a wipe or cloth that is pre-wetted with a liquid formulation containing cationic antimicrobials for application to a substrate such as a hard surface.

Viscose, wood pulp or other cellulosic-based substrates are desirable for the production of wipes from an environmental perspective since they can be flushable and/or biodegradable. In contrast, polyester or polypropylene-based cloths are not flushable or readily biodegradable but have the advantage, as far as a wipe for application of an antimicrobial is concerned, in that they do not adsorb cationic antimicrobials. Thus, currently the end-user has to choose between an effective antimicrobial wipe or a "green" wipe substrate.

It is desirable to provide effective antimicrobial wipes which have improved flushability and biodegradability or which are flushable or readily biodegradable.

It would also be advantageous to provide wipes which in use deliver a residual anti-microbial effect.

The listing or discussion of an apparently prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge.

The present invention provides anti-microbial wipes which address one or more of the foregoing deficiencies.

The present invention provides an anti-microbial wipe comprising a substrate comprising from 1 to 100% by weight of a cellulosic material and incorporating a composition comprising (i) an anti-microbial component; (ii) a non-ionic surfactant; (iii) a polar solvent; and optionally (iv) a hydrophobic material; wherein the anti-microbial component (i) comprises (I) (a) at least one quaternary ammonium compound as defined below and optionally (b) one or more additional anti-microbial agents, or (II) at least one polymeric biguanide as the only anti- microbial agent and wherein the composition is substantially free of anionic surfactant.

The anti-microbial wipes of the invention may provide a residual anti-microbial effect and/or an enhanced kill rate when they are used to treat a surface. As used herein, by the term "wipe" or "wipes" we mean a substrate (preferably as disposable substrate) such as a porous or absorbent sheet or cloth, woven or non-woven, which has been pre-treated with an anti-microbial composition as described herein. The wipes of the invention are particularly advantageous as they enable safe and convenient anti-microbial treatment of a surface without the need for dilution or spraying.

The wipes of the invention are typically prepared by absorbing an anti-microbial composition onto the substrate to form a moist wipe. A single wipe or several wipes (for example 10, 20, 50 or 100 wipes) may then be stored in such a manner that they remain moist on storage. For example the wipes of the invention may be stored in re-sealable containers which prevent evaporation of the components from the anti-microbial composition.

By the term "moist" we mean that on contact with a surface, for example a hard surface or the skin, the wipes are capable of transferring a quantity of a liquid antimicrobial composition to the surface.

The amount of antimicrobial composition that is added to the substrate will vary depending on factors such as the nature of the substrate, the type of container in which the wipe(s) will be stored, and the desired end use for the wipe. Typically the amount of antimicrobial composition is from about 50 to 600 weight percent of anti-microbial composition based on the dry weight of the substrate, preferably from about 100 to 450 weight percent of antimicrobial composition based on the dry weight of the substrate. If the amount of liquid is below the lower limit quoted above the wipe may be too dry and may not be capable of transferring antimicrobial composition to the surface and so limiting the anti-microbial effectiveness of the wipe. If the amount of liquid is too great, the substrate may be over saturated and soggy and the anti-microbial composition may pool in the bottom of the container. This is undesirable from an end-user perspective since the excess liquid may result in prolonged drying times or may drip undesirably onto non-target surfaces. Further, the excess liquid represents an undesirable additional cost to the end-user.

The moist nature of the wipes means that the wipes can be used to provide an anti-microbial effect without the need to dilution and without the need for any other equipment. The substrates used to prepare the wipes of the present invention may be made of any suitable woven or non-woven material.

Examples of suitable materials include, but are not limited to, non-woven fibrous sheet materials and those made of fibres from natural sources such as wood pulp, viscose or other cellulose based materials, silk fibres and keratin fibres. The materials comprise from 1 to 100% by weight of a cellulosic material. For example, 100% cellulosic materials such as viscose or wood pulp may be used. Other preferred materials include blends of cellulosic and non-cellulosic materials, such as blend of viscose with synthetic substrates such as polyester or polypropylene. Blended materials may comprise from 1 to 99.9 % by weight of a cellulosic material such as viscose, for example from 15 to 90% by weight or from 40 to 80 % by weight of a cellulosic material such as viscose.

Examples of suitable keratin fibres include, but are not limited to, wool fibres, and camel hair fibres. Examples of suitable cellulosic fibres include, but are not limited to, wood pulp fibres, cotton fibres, hemp fibres, jute fibres, flax fibres and mixtures thereof.

Optionally, the non-woven materials may comprise one or more binders. Suitable binders may be based on polymeric latex emulsions. Suitable binders include crosslinked acrylates, crosslinked vinyl acetate/acrylic ester copolymers, plasticised crosslinked polyvinyl acetate, crosslinked styrene-butadiene copolymers, and other homopolymers or copolymers containing one or more of acrylates, vinyl acetate, ethylene, vinyl chloride, and vinylidene dichloride. In another aspect, the non-woven materials may be substantially free of binder. For example, they may be substantially free of a polyvinyl alcohol based binder.

The substrate should be water insoluble. By this we mean that the substrate does not dissolve in water. Additionally one or more of the following non-limiting properties are desirable properties of the substrate (a) appropriate wet strength for the intended use, (b) if necessary for the intended use, sufficient abrasiveness, (c) sufficient thickness, (d) appropriate size, (e) appropriate loft and porosity, (f) adequate liquid absorption capacity and (g) acceptable liquid absorption rate. Clearly, the most desirable combination of properties will depend on the intended use for the wipes and would be within the knowledge of the person of ordinary skill in the art.

Methods for making the substrates used in the present invention are well known in the art and do not need to be described here. For example, the substrate may be meltblown, co- formed, air-laid, wet laid, thermal bonded, bonded-carded web, and/or hydro-entangled (also known as spunlaced) materials.

Suitable materials for use as the substrate in the wipes of the invention are well known in the art and are readily available from commercial sources. For example, suitable substrates are available from, Sandler, Jacob Holm, VaporJet and NR Spuntech.

The substrates may comprise a single layer of material or they may comprise two or more layers (for example, 2-ply, 3-ply, 4-ply or 5-ply materials). In substrates containing 2 or more layers each of the layers may be the same or different, ie they may have the some or differing compositions and/or the same or different thicknesses.

As known in the art, the preferred weight of the substrate will vary according to the intended use. The substrates used in the present invention typically have a weight of from about 10gsm to about 150gsm, preferably from about 20gsm to about 100gs and more preferably from about 20gsm to about 80gsm, for example from about 25 to 65 gsm, typically about 50 gsm.

The wipes of the invention may be provided in any suitable form. For example, they may be presented in the form of a stack of moist sheets packed in a moisture impermeable container (for example made of a plastics material) or a moisture impermeable pouch. They may be folded or unfolded. They may be provided in the form of a continuous sheet of material which is perforated at intervals so that individual wipes may be separated from the continuous sheet. When in the form of a continuous material, the wipes may be stored wound into a roll, which is packaged in a moisture impermeable container (for example made of a plastics material).

Preferable the container or pouch is re-sealable, although single use pouches containing one or two wipes are also envisaged.

The anti-microbial compositions that are loaded onto the substrates typically have a viscosity of from about 0.1 x 10^"6 to about 2000 x 10^"6 m /s (about 0.1 to about 2000 (centipoise) cP), preferably less than about 1000 x 10^"6 m²/s (about 1000 cps), more preferably from about 0.5 x 10^"5 to about 500 x 10^"6 m²/s (about 0.5 to about 500 cP), most preferably from about 0.5 x 10-⁶ to about 100 x 10^-6 m²/s (about 0.5 to about 100 cP). The substrates can be loaded with the antimicrobial composition using any suitable technique known in the art, such as coating, spraying, dipping and soaking.

The anti-microbial compositions which are used to produce the wipes of the invention comprise (i) an anti-microbial component; (ii) a non-ionic surfactant; (iii) a polar solvent; and optionally (iv) a hydrophobic material; wherein the anti-microbial component (i) comprises (a) at least one quaternary ammonium compound and optionally (b) one or more additional antimicrobial agents, and wherein the composition is substantially free of anionic surfactant. While it is envisaged that the compositions used can contain additional ingredients as described below and other ingredients that are standard in the art, the compositions used may consist of or consist essentially of the components listed in the paragraph above.

In an alternative, the anti-microbial component may be (a) at least one polymeric biguanide and optionally (b) one or more additional anti-microbial agents.

The compositions used in the invention may be substantially free of alcohol. Alternatively or additionally, they may be free of one or more of 2-({2- [bis(carboxymethyl)amino]ethyl}(carboxymethyl)amino)acetic acid (EDTA) and EDTA containing materials such as EDTA salts, chelating agents and citrate salts.

The compositions may comprise (II) at least one polymeric biguanide as the only antimicrobial agent. In this aspect, they may contain one or more polymeric biguanides but may not contain any antimicrobial agents in addition to polymeric biguanides.

The present inventors have surprisingly found that by including a non-ionic surfactant in the compositions used in the invention improved levels of release of cationic antimicrobial agents from substrates containing anionic binding sites such as cellulosic fibres can be achieved without the need to use biocide release agents. Thus, the compositions used in the present invention do not typically comprise biocide release agents such as cationic compounds to at least partially compete with the cationic biocide for the anionic species sites on the substrate. Compounds which are known to have this effect include citrates such as potassium and sodium citrate, tartrates such as sodium and potassium tartrate, lactates such as potassium and sodium lactate, salicylate salts of sodium and/or potassium, sulphates such as magnesium sulphate, chlorides such as sodium, potassium and ammonium chloride and the like. Compounds of this type are typically not used in the present invention. This means that the compositions used in the present invention are typically free from biocide release agents, such as those listed above and are typically not used in combination with such agents, for example such agents typically are not used at the same time, prior to or subsequent to the use of a wipe of the invention.

As used herein, by the term "substantially free of we mean that the composition need not be totally free of a specified ingredient but if that ingredient is present it must be present in an amount that does not affect the properties of the compositions or formulations used in the invention.

The important thing for compositions to provide the required anti-microbial effect is not typically the concentration of the components in the final solution; rather it is the ratio of the number of molecules of the components. This ratio will remain the same whether the composition is in a concentrated form or whether it is in a dilute form.

Typically, the ratio of the number of molecules of the component (ii) to the number of monomer units of component (i) ranges from about 150:1 to about 0.1:1 or 1 :1 or to about 5:1 or to about 10:1 , preferably from about 100:1 to about 5:1 or from 40:1 to 0.1 :1 , more preferably from about 90:1 or 80:1 to about 5:1 , still more preferably from about 70:1 to about 25:1 or about 10:1 , most preferably from about 30:1 to about 60:1 , for example from about 10:1 to about 50:1.

In this ratio we have referred to the number of monomer units rather than the number of molecules because some of the compounds used as component (i) are polymeric. For polymeric compounds it is the ratio of active units, i.e. the ratio of monomer units to the number of molecules of component (ii) that is important. Polymeric biguanides such as PHMB are polymeric. For example Vantocil IB (a commercial PHMB) has the formula (C₈H₁₈N₅CI)_n wherein n =12 to 16. In this case, the number of active units is 12 to 16 times the number of molecules. The quaternary ammonium compounds used in this invention are typically monomeric. The number of monomer units of these quaternary ammonium compounds is the same as the number of molecules.

Typically, but not essentially, the compositions used in the invention have a concentration of component (i) of from about 10 to about 10,000 ppm, such as from about 250 to about 1000 ppm or from about 60 to about 100 ppm and a concentration of component (ii) of from about 10 to about 10,000 ppm, such as from 250 to about 1000 ppm or from about 60 to about 100 ppm (based on the number of molecules). Without wishing to be bound by theory it is believed that for many combinations of non-ionic surfactant and anti-microbial component these minimum concentrations are required to obtain the necessary dispersion properties in the compositions. However, it will be appreciated that for some applications lower concentrations of components (i) and (ii) may be suitable.

By the term "anti-microbial" we mean that a compound or composition that kills and/or inhibits the growth of microbes (microorganisms). The term "microbiocidal" is used to refer to compounds or compositions that kill microbes. The compositions of the invention are anti- microbial and/or microbiocidal.

A microorganism or microbe is an organism that is microscopic (too small to be seen by the human eye). Examples of microorganisms include bacteria, fungi, yeasts, moulds, mycobacteria, algae spores, archaea and protists. Microorganisms are generally single- celled, or unicellular organisms. However, as used herein, the term "microorganisms" also includes viruses.

Preferably, the compositions used comprise at least one anti-microbial agent selected from anti-bacterial, anti-fungal, anti-algal, anti-sporal, anti-viral, anti-yeastal and anti-moldal agents and mixtures thereof. More preferably, the compositions of the invention comprise at least one anti-bacterial, anti-viral, anti-fungal and/or anti-moldal agent.

As used herein, the terms anti-bacterial, anti-fungal, anti-algal, anti-viral, anti-yeastal and anti-moldal agents are intended to refer to agents, which inhibit the growth of the respective microorganisms but do not necessarily kill the microorganisms and agents which kill the respective microorganisms. Thus, for example, within the term anti-bacterial we include agents, which inhibit the growth of bacteria but may not necessarily kill bacteria and bactericidal agents which do kill bacteria. As the skilled person will appreciate, the word ending "cidal" as used in for example "bactericidal" and "fungicidal" is used to describe agents which kill the microorganism to which it refers. Thus, in these examples, bactericidal refers to an agent that kills bacteria and fungicidal refers to an agent that kills fungus. Examples of bactericides include myobactericides and tuberculocides. Preferably, the compositions used comprise at least one agent selected from bactericidal, fungicidal, algicidal, sporicidal, virucidal, yeasticidal and moldicidal agents and mixtures thereof. More preferably, the compositions of the invention comprise at least one bactericidal, virucidal, fungicidal and/or moldicidal agent.

The compositions used are effective against a wide range of organisms, including Gram negative and Gram positive spore formers, yeasts, and viruses. By way of example, the microorganisms which the compositions of the present invention can be effective against include:

Viruses such as HIV-1 (AIDS Virus), Hepatitis B Virus (HVB), Hepatitis C Virus (HCV), Adenovirus, Herpes Simplex, Influenza (including seasonal flu, H1 N1 and H5N1), Respiratory Syncytial Virus (RSV), Vaccinia, Avian Influenza virus, Avian Bronchitis, Pseudorabies virus, Canine Distemper, Newcastle Disease, Rubella, Avian Polyomavirus, Feline leukemia, Feline picornavirus, Infectious Bovine rhinotracheitis, Infectious Bronchitis (Avian IBV), Rabies, Transmissible gastroenteritis virus, arek's Disease. Funguses such as Trichophyton mentagrophytes, Aspergillus niger, Candida albicans, Aspergillus flavus, Aspergillus fumigatus, Trichophyton interdigitale, Alternaria tenius, Fusarium oxysporum, Geotrichum candidum, Penicillium digitatum, Phytophthora infestans, Rhizopus nigricans, Trichoderma harzianum, Trichophyton interdigitale. Bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella choleraesuis, Acinetobacter baumannii, Brevibacterium ammoniagenes, Campylobacter jejuni, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas cepacia, Salmonella schottmuelleri, Salmonella typhi, Salmonella typhimurium, Serratia marcescens, Shigella dysenteriae, Shigella flexneri, Shigella sonnei, Staphyloccus epidermidis, Streptoccus faecalis, Streptoccus faecalis (Vancomycin resistant), Streptococcus pyogenes, Vibrio chlorae, Xanthomonas axonopodis pv citri (Citrus canker), Acinetobacter calcoaceticus, Bordetella bronchiseptica, Chlamydia psittaci, Enterobacter cloacae, Enterococcus faecalis, Fusobacterium necrophorum, Legionella pneumophila, Listeria monocytogenes, Pasteurella multocida, Proteus vulgaris, Salmonella enteritidis, Mycoplasma gallisepticum, Yersinia enterocolitica, Aeromonas salmonicida, Pseudomonas putida, Vibrio anguillarum.

The compositions used are preferably effective against one or more of P. aeruginosa (ATCC 15442, PaFH72/a), E.coli (ATCC 10536, ECFH64/a, 0157:H7 (toxin producing strain), CCFRA/896, 0157:H7 (non-toxigenic strain), CCFAA 6896, ATCC 10538), S. aureus (including MRSA, (e.g. NCTC 12493 MRSA, ATCC 12493 MRSA), VISA, ATCC 6538, 5a FH73/a), Entercoccus hirea (ATCC 10541 , EhFH 65/a), Feline Coronavirus (SARS surrogate), Feline Calcivirus (Hum. Norovirus surrogate), Salmonella typhimurium (StFH 68/b), Yersinia enterocolitica (YE FH67/b), Listeria monocytogenes (Lm FH66/c), Saccharomyces cerevisiae, Bacillus Subtilis (ATCC 6633), Bacillus stearothermophilus (NCTC 10339), Clostridium dificile (NCTC 11209), Candida albicans (ATCC 1023), Aspergillus niger (ATCC 16404), Mycobacterium smegmatis (TB stimulant) and Influenza (including seasonal flu, H1 N1 and H5N1).

In one aspect, the compositions contain at least one quaternary ammonium anti-microbial agent. In a particular aspect, the compositions contain at least two anti-microbial agents. They may additionally comprise any other suitable anti-microbial agent(s), such as those described in the EPA (United States Environmental Protection Agency) Listing and Annex I of the EC Biocides Directive. Suitable anti-microbial agents (b) include polymeric biguanidines, amphoteric compounds, iodophores, phenolic compounds, polymerised quaternary ammonium compounds, hypochlorites and nitrogen based heterocyclic compounds.

The anti-microbial agent(s) used are preferably water soluble at room temperature and pressure.

Preferred anti-microbial agents include anti-microbial agents with surfactant properties and polymeric biguanidines (e.g. polyhexamethylene biguanidine (PHMB)), isothiazolones, ortho phenyl phenol (OPP), and nitro bromopropanes (e.g. bronopol (INN), 2-bromo-2- nitropropane-1 ,3-diol) and polymerised quaternary ammonium compounds. A particularly preferred anti-microbial agent for use in the present invention is polyhexamethylene biguanidine (PHMB). PHMB is commercially available from Arch Biocides as Vantocil IB.

The following compounds are typically not used as additional antimicrobial agents in the compositions used in the present invention alcohols, peroxides, boric acid and borates, chlorinated hydrocarbons, organometallics, halogen-releasing compounds, mercury compounds, metallic salts, pine oil, organic sulphur compounds, silver nitrate, quaternary phosphate compounds, and/or phenolics. The compositions used in the present invention may be substantially free or free of these compounds.

In one aspect, the compositions used in the invention comprise cationic anti-microbial agents only.

A preferred combination of anti-microbial agents is the combination of at least one polymeric biguanidine such as PHMB with one or more, for example two or more quaternary ammonium compounds. This combination may be used in combination with other antimicrobial agents or may be used alone.

In another aspect, the compositions may comprise at least one polymeric biguanide as the only anti-microbial component. The compositions may comprise PHMB as the only antimicrobial agent.

The quaternary ammonium compounds used in the present invention are examples of "antimicrobial agent with surfactant properties". By the term "anti-microbial agent with surfactant properties" we mean a material which can kill or inhibit the growth of microbes (microorganisms) and also has the effect of altering the interfacial tension of water and other liquids or solids and/or reduces the surface tension of a solvent in which it is used. More particularly, the anti-microbial agents with surfactant properties used in the present invention can kill or inhibit the growth of microbes and typically when introduced into water lower the surface tension of water.

The quaternary ammonium compounds, also know as "quats", compounds typically comprise at least one quaternary ammonium cation with an appropriate anion. The quaternary ammonium cations are permanently charged, independent of the pH of their solution. The structure of the cation can be represented as follows:

The groups R_{1 f} R₂, R₃ and R₄ can vary within wide limits and examples of quaternary ammonium compounds that have anti-microbial properties will be well known to the person of ordinary skill in the art.

Each group R^ R₂, R₃ and R4 may, for example, independently be a substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, alkylaryl, arylalkyl, cycloalkyl, (aromatic or non-aromatic) heterocyclyl or alkenyl group. The total number of carbon atoms in the groups R_{1 f} R₂, R₃ and R₄ must be at least 4. Typically the sum of the carbon atoms in the groups R^ R₂, R₃ and R₄ is 10 or more. In a preferred aspect of the invention at least one of the groups Ri , R₂, R3 and R₄ contains from 8 to 18 carbon atoms. For example, 1, 2, 3 or 4 of R₂, R3 and R₄ can contain from 8 to 18 carbon atoms or 10 to 16 carbon atoms. Preferably, if each of R_{1 (} R₂, R₃ and R4 is an unsubstituted or uninterrupted alkyl group each of R_{1 t} R₂, R₃ and R₄ is methyl or a C_6-i₂ alkyl group;

Suitable substituents for the groups Ri , R₂, R₃ and R4 may be selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, heterocyclyl, substituted heterocyclyl, cycloalkyi, substituted cycloalkyi, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyi, substituted arylalkyi, F, CI, Br, I, -OR', -NR'R", -CF₃, -CN, -N0₂, -C₂R\ - SR\ -N₃, -C(=0)NR'R", -C(=0)R', -NR'C(=0)R", -C(=0)OR', -O(CR'R")_rC(=0)R', -

-0(CR'R")rNR"S0₂R', -OC(=0)R', -OC(=0)NR'R", -NR'C(=0)OR", -S0₂R',

-S0₂NR'R", and -NR'S0₂R", wherein R' and R" are individually hydrogen, d-C₈ alkyl, cycloalkyi, heterocyclyl, aryl, or arylalkyi, and r is an integer from 1 to 6, or R' and R" together form a cyclic functionality, wherein the term "substituted" as applied to alkyl, alkenyl, heterocyclyl, cycloalkyi, aryl, alkylaryl and arylalkyi refers to the substituents described above, starting with F and ending with -NR'S0₂R".

When one or more of Ri , R₂, R₃ and R₄ is interrupted, suitable interrupting groups include but are not limited to heteroatoms such as oxygen, nitrogen, sulphur, and phosphorus-containing moieties (e.g. phosphinate). A preferred interrupting group is oxygen. One or more of the groups of Ri , R₂, R₃ and R4 may be interrupted with one or more for example, 1 , 2, or 3 heteroatoms.

Suitable anions for the quats include but are not limited to halide anions such as chloride, fluoride, bromide or iodide and the non halide sulphate. Preferred quats are those having the formula:

(CH₃)_n(A)_mN⁺X- wherein A may be as defined above in relation to Ri , R₂, R₃ and R₄. X^' is selected from chloride, fluoride, bromide or iodide and sulphate (preferably chloride or bromide), n is from 1 to 3 (preferably 2 or 3) and m is from 1 to 3 (preferably 1 or 2) provided that the sum of n and m is 4. Preferably, A is a C₆.₂₀ (e.g. C_{6 or 8}-i8, i.e. having 6,7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17 or 18 carbon atoms or C_{6 or 8}.₁₂ or Ci_2-i₈) substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, alkylaryl, arylalkyl or cycloalkyl group (wherein suitable substituents are as defined above in relation to R₂, R3 and R₄). Each group A may be the same or different. A preferred group of the compounds of formula (CH₃)_n(A)_mN⁺X^' are those wherein n = 3 and m = 1. In such compounds A may be as defined above and is preferably a C6-20 substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, or alkylaryl group. Examples of this type of quaternary ammonium compound include Cetrimide (which is predominately trimethyltetradecylammonium bromide), dodecyl- trimethylammonium bromide, trimethyltetradecylammonium bromide, hexadecyltrimethylammonium bromide.

Another preferred group of the compounds of formula (CH₃)_n(A)_mN⁺X^" are those wherein n = 2 and m = 2. In such compounds A may be as defined above in relation to R-,, R₂, R₃ and R₄. Preferably A is a C_6-2o substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, or alkylaryl group. For example, A may represent a straight chain, unsubstituted and uninterrupted C_8-12 alkyl group or a benzyl group. In these compounds, the groups A may be the same or different. Examples of this type of compound include didecyl dimethyl ammonium chloride and dioctyl dimethyl ammonium chloride.

Examples of the preferred quaternary ammonium compounds described above include the group of compounds which are generally called benzalkonium halides and aryl ring substituted derivatives thereof. Examples of compounds of this type include benzalkonium chloride, which has the structural formula:

wherein R may be as defined above in relation to R^ R₂, R₃ and R . Preferably, R is a 5.18 alkyl group or the benzalkonium chloride is provided and/or used as a mixture of ( is alkyl groups, particularly a mixture of straight chain, unsusbtituted and uninterrupted alkyl groups n-C₈H₁₇ to n-C₁₈H₃₇, e.g. n-Ci₂H₂₅ to n C ₈H₃₇ mainly n-C₁₂H₂₅ (dodecyl), n-C₁ H₂₉ (tetradecyl), and n-C₁₆H₃₃ (hexadecyl).

Other preferred quaternary ammonium compounds include those in which the benezene ring is substituted, for example alkyldimethyl ethylbenzyl ammonium chloride. As an example, a mixture containing, for example, equal molar amounts of alkyi dimethyl benzyl ammonium chloride and alkyldimethyl ethylbenzyl ammonium chloride may be used.

Mixtures of, for example, one or more alkyl dimethyl benzyl ammonium chlorides and one or more compounds of formula (CH₃)2(A)₂N⁺X^", such as didecyl dimethyl ammonium chloride may be used.

Typically, mixtures of quaternary ammonium compounds are used. In these mixtures, the quaternary ammonium compounds may be mixed with any suitable inert ingredients. Commercially available benzalkonium chloride often contains a mixture of compounds with different alkyl chain lengths. Examples of commercially available benzalkonium chlorides are shown in the following Table.

It will be appreciated that a single CAS number often refers to more than one blend or mixture. A CAS classification for commercial preparation typically covers blends comprising specified compounds in amounts within defined ranges. The compositions which have the CAS numbers quoted above are only examples of compositions having a given CAS number that may be used in the present invention.

Suitable quaternary ammonium compounds in which one or more of R¹, R², R³, R⁴ are interrupted by a heteroatom include domiphen bromide ((Dodecyldimethyl-2- phenoxyethyl)ammonium bromide) and benzethonium chloride (/V-benzyl-A/,/\/-dimethyl-2-{2- [4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethoxy}ethanaminium chloride).

Other quaternary ammonium compounds suitable for use in the invention include, but are not limited to, bridged cyclic amino compounds such as the hexaminium compounds.

Other examples of quats which may be used in the present invention include Cetalkonium Chloride, Glycidyl Trimethyl Ammonium Chloride, Stearalkonium Chloride; Zephiran chloride (R); Hyamine 3500; Diisobutyl phenoxyethoxyethyldimethylbenzylammonium chloride; Hyamine 1622(R); Cetalkonium Chloride; Cetyldimethylbenzyl-ammoniurn chloride; Triton K 12; Cetyltrimethylammonium bromide; Retarder LA; Glycidyltrimethyl-ammonium chloride; Benzethonium Chloride CAS 121-54-0; Cetalkonium Chloride CAS 122-18-9; Cetrimide CAS 8044-71-1 ; Stearalkonium Chloride CAS 122-19-0; Cetrimonium Bromide CAS 57-09-0.

Particularly preferred quaternary ammonium compounds include benzyldimethyl-n- tetradecyl-ammonium chloride, benzyldimethyl-n-dodecyl-ammonium chloride, n-dodecyl-n- tetradecyldimethyl-ammonium chloride and benzyl-Ci₂-Ci₆-alkyl-dimethyl-ammonium chloride, benzyl-cocoalkyl-dimethyl-ammonium chloride, di-n-decyldimethylammonium chloride.

An example of a suitable mixture is a composition comprising octyl decyldimethyl ammonium chloride, didecyl dimethyl ammonium chloride, dioctyl dimethyl ammonium chloride, and alkyl (C₁₄, 50%; Ci2, 40%, C-I6, 10%) dimethyl benzyl ammonium chloride (in a ratio of about 2:1 :1 :2.67).

Another suitable mixture is a mixture of octyldecyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride, dioctyl dimethyl ammonium chloride, and alkyl (d₄, 50%, C ₂, 40%, Cie, 10%) dimethyl benzyl chloride (in a ratio of about 2:1:1 :2.67).

Another suitable mixture is octyldecyl dimethyl ammonium chloride, dioctyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride, and alkyl (Ci₄, 50%; C ₂, 40%; C₁₆, 10%) dimethyl benzyl ammonium chloride (in a ratio of about 2:1:1 :2.67). Examples of other commercially available quaternary ammonium compounds include BAC 50 (from Thor biocides), and Nobac (Benzalkonium chloride, from Mason Quats).

In one aspect of the invention, the composition used does not comprise a quaternary ammonium compound in which one or more of R¹, R², R³ and R⁴ are interrupted by a heteroatom such as oxygen, nitrogen, sulphur or phosphorus-containing moieties. In other words the composition used may, in some aspects, not include one or more of domiphen bromide ((Dodecyldimethyl-2-phenoxyethyl)ammonium bromide) and benzethonium chloride

(A-benzyl-A/,/\/-dimethyl-2-{2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethoxy}ethanaminium chloride). The quaternary ammonium compounds may be used in combination with other anti-microbial agents with surfactant properties. Other suitable anti-microbial agents with surfactant properties include anionic and cationic surfactant materials as well as amphoteric materials; the use of cationic surfactant materials is preferred. Examples include quaternary bisammonium surfactants, alkyl betaines, sulfobetaines, alkyl amine oxides, arginine-based cationic surfactants, anionic amino acid based surfactants and mixtures thereof, for example a mixture of alkyl betaine(s) or sulfobetaine(s) and alkyl amine oxides.

An example of a Betaine which is suitable for use in the present invention is Macat^® Ultra (available from Mason Chemical Company). Macat^® Ultra CG comprises 30% coco (Ci₂) amidopropyl dimethyl glycine (betaine) in water.

An example of an alkyl amine oxide which is suitable for use in the present invention is Macat^® Ultra CDO (available from Mason Chemical Company), a 30% solution of coco (C₁₂) amidopropyl dimethyl amine oxide in water.

One or more of any of the anti-microbial agents with surfactant properties described above can be used in the compositions of the invention.

In one aspect, the compositions comprise another anti-microbial agent (b) in addition to the component (a). The ratio of molecules of component (a) to molecules of another antimicrobial agent (b), is preferably from about 1 :2 or about 1 :1 to about 50:1 , preferably about 2:1 to about 30:1 , more preferably from about 4:1 to about 20:1 , most preferably from about 8: 1 to about 15:1 , for example about 10: 1. The amount of component (a) will vary depending on a number of factors, such as the intended use of the composition and the particular compound(s) used as component (a).

Typically, the compositions used do not comprise 1 ,3-bis-(P-ethylhexyl)-5- aminohexahydropyrimidine (hexetidine). In particular, it is preferred not to use hexetidine in combination with PHMB. Suitable non-ionic surfactants for use as component (ii) include but are not limited to ethylene oxide/propylene oxide block polymers, fatty esters and amides, alkylpolyglycosides and polyalkoxylated derivatives of general structure R(OCHXCH₂)_nOH, where R is derived from an alcohol, phenol, carboxylic acid, ester, amine or amide, X is independently H or CH₃ and n is from 1 to 50, preferably from 2 to 20. Examples of these include; polyethoxylated sorbitan esters, fatty esters of sorbitan, ethoxylated fatty esters (containing from 1 to 25 units of ethylene oxide), polyethoxylated C₈-C₂₂ alcohols (containing from 1 to 25 units of ethylene oxide), polyethyoxylated C₆-C₂₂ alkylphenols (containing from 5 to 25 units of ethylene oxide). Further polyalkoxylated derivatives include but are not limited to nonyl phenol ethoxylate (9EO), Nonyl phenol ethoxylate (2EO), octyl phenol ethoxylate (10EO), Ci₂/C₁₄ synthetic ethoxylate (8EO), stearyl alcohol ethoxylate (7EO), cetostearyl alcohol ethoxylate (20EO), coconut fatty amine ethoxylate (10EO), sorbitan monolaurate ethoxylate, 80%PO/20%EO and sorbitan monolaurate 4EO. Polypropoxylated compounds can also be used, as can the combination of polyethoxylated compounds and polypropoxylated compounds. Examples of fatty esters and amides include, but are not limited to coconut diethanolamide (shampoo foam booster), sorbitan monolaurate, di-isopropyl adipate and cetostearyl stearate. Alkyl poly glycosides (APGs), of typical structure R-0(Sac)_n where R is an alkyl group and Sac is a saccharide derivative. Examples of APGs include, but are not limited to, alkylpolyglucosides with n = 1 to 10 such as C^o, preferably C_8-10 alkyl glucosides, eg Surfac APG (D-Glucopyranose oligomers C₈.io alkyl glucosides, CAS 161074-97-1, available from Seppic, UK). Other commercial examples of suitable non-ionic surfactants include Neodol 25-7 (C 2/15 alcohol 7 ethoxylate (EO), CAS 68131-39-5), Surfac LM90/85 (C12/15 alcohol 9 ethoxylate (EO), CAS 68131-39-5), Surfac 65/95 (C9/11 alcohol 6.5 ethoxylate (EO), CAS 68439-45-2), Tomadol PF9 (C9/11 alcohol 6.0 ethoxylate (EO), CAS 68439-46-3), Surfac T80 Veg (Polysorbate 80, Polyoxyethylene sorbate mono oleate, CAS 9005-65-6), Tween 60 (Polysorbate 60, Polyoxyethylene sorbate mono stearate, CAS 9005- 67-8), Tween 40 (Polysorbate 40, Polyoxyethylene sorbate mono palmitate, CAS 9005-66-7), Surfac T-20 (Polysorbate 20, Polyoxyethylene sorbate mono laurate, CAS 9005-64-5), Surfac PGHC (Hydrogenated Castor oil 40EO, CAS 61788-85-0), Ninol 49-CE (Coconut diethanolamide, CAS 68603-42-9).

A preferred class of non-ionic surfactants for use in the present invention is alcohol ethoxylates, particularly alcohol ethoxylates having from 2 to 15 ethoxylated units. Examples of suitable alcohol ethoxylates include linear alcohol ethoxylates such as those sold under the Tomadol and Neodol trade names. Preferred combinations of surfactants include but are not limited to CAPB and a non-ionic surfactant, such as an alcohol ethoxylate or an APG, an amine oxide and a non-ionic surfactant, such as an alcohol ethoxylate or an APG. The compositions used may contain more than one surfactant. For example, they may contain more than one non-ionic surfactant, eg 2, 3 or 4 non-ionic surfactants. Alternatively, in addition to the non-ionic surfactant the compositions may comprise one or more anionic, cationic and/or amphoteric surfactants or mixtures thereof. In a particular aspect of the invention the formulation comprises at least one non-ionic and at least one amphoteric surfactant.

Preferably, the compositions used in the invention are substantially free of or do not comprise an anionic surfactant. In another aspect, the compositions of the invention do not comprise an amphoteric surfactant.

The compositions used in the invention may optionally contain a hydrophobic material. Compounds suitable for use as the hydrophobic material include silanes, siloxanes, silicones, polysiloxanes, fluorine-containing aliphatic compounds and mixtures thereof. These hydrophobic materials can be used in combination with other materials such as polyalkylene glycols.

If the compositions comprise one or more hydrophobic materials, the hydrophobic material is typically chemically inert. The hydrophobic material is typically capable of associating with other components of the fluid by non-covalent bonds.

As used herein, the term "fluorine-containing aliphatic compounds" refers to Cs to C₂o linear or branched alkanes or alkenes which contain at least 0.1 fluorine atoms per carbon atom and as a maximum are fully fluorinated. Typically, the fluorine-containing aliphatic compound will contain an average of from 1 to 2 fluorine atoms per carbon atom.

The hydrophobic material may for example comprise at least one polysiloxane, preferably at least one polydimethylsiloxane. For example, a mixture of two or more polysiloxanes having different molecular weights and/or viscosities may be used. When a mixture of polysiloxanes is used, the mixture preferably comprises at least one polysiloxane containing up to about 500, more preferably 50 to 200 (e.g. about 100) monomer units and at least one polysiloxane containing more than 500, more preferably 750 to 1000 monomer units. These polysiloxanes typically have a viscosity of from 35 to 750 centistokes, preferably 35 to 400 centistokes, more preferably 35 to 150 centistokes, for example about 100 centistokes.

These polysiloxanes typically have a surface tension of less than 20 mN/m at 20 °C, for example from 5 to 19 mN/m, more preferably from 7 to 14 mN/m and most preferably from 8 to 12 mN/m at 20 °C (eg about 10 mN/m at 20 °C).

Other hydrophobic materials that may be included in the compositions include shorter chain siloxanes selected from these having the formulae (H₃C)[SiO(CH₃)2]nSi(CH₃)3, and (H3C)[SiO(CH3)H]nSi(CH₃)3 where n is an integer, of from 1 to 24, more preferably from 1 to 12 and most preferably from 1 to 8, for example n may be 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12, especially 1 , 2, 3 or 4. These materials are often referred to as (poly)dimethylsiloxanes (CAS # 9016-00-6) and (poly)methylhydrosiloxanes respectively. These materials are linear siloxanes. Cyclic siloxanes are typically not used in this invention. These materials are typically liquid at ambient temperature and pressure (e.g. about 20°C at atmospheric pressure).

Preferred siloxanes suitable for use in the present invention typically have a molecular weight of from about 100 to about 2000 g/mol, preferably from about 148 to about 1864 (such as from about 162 to about 1864 or about 148 to about 1528), more preferably from about 148 to about 1000 or about 976 (e.g. from about 162 to about 976 or about 148 to about 808), such as from about 148 to about 680 (e.g. from about 162 to about 680 or about 148 to about 568), particularly from about 148 to about 384 (e.g. from about 162 to about 384 or about 148 to about 328).

Examples of preferred (poly)dimethylsiloxanes are hexamethyldisiloxane (CAS # 107-46-0), octamethyltrisiloxane (CAS # 107-51-7), decamethyltetrasiloxane (CAS # 141-62-8), dodecamethylpentasiloxane (CAS # 141-63-9). These (poly)dimethylsiloxanes correspond to the compounds of formula (H₃C)[SiO(CH₃)2]nSi(CH₃)3, wherein n = 1, 2, 3 and 4 respectively.

These materials are generally also strongly hydrophobic. By this we include the meaning that it is repelled from a mass of water and by itself is substantially insoluble in water. By the term "substantially insoluble in water", we mean that the material typically has a solubility of less than 2g/100g water at 20°C and atmospheric pressure, such as less than 1g/100g water, preferably, less than 0.5g/100g water, for example less than 0.1g/100g water, e.g. less than 0.01g/100g water. The siloxanes which may be used in the compositions typically have a viscosity of from about 0.1 to about 100 centistokes at atmospheric pressure and at about 20 °C, preferably from about 0.2 to about 20 centistokes. Preferred siloxanes have a viscosity of from about 0.5 to about 5 centistokes, e.g. 0.65, 1 , 1.5, 2, 3, 4, 5, 6, 7, 8, 9, or 10 centistokes or from 3 to 5 centistokes.

The siloxanes preferably used in the present invention, due to their relatively low molecular weight, are relatively volatile. For example, they typically have a boiling point of less than about 120°C at atmospheric pressure, for example from about 100 to 120°C. Hexamethydisiloxane, for example, has a boiling point of about 101°C at atmospheric pressure.

The siloxanes described above may be used alone or in combination. Many commercially available siloxanes are provided as mixtures and these can be used in the present invention without the need to separate the components of the mixture. Details of commercially available siloxanes which are suitable for use in the compositions of the invention are set out, for example, at http://www.clearcoproducts.com/standard pure silicones.html. For example a mixture of two, three, four, five or more siloxanes may be used. If a combination of siloxanes is used the materials may be used in equal or differing amounts. For example each siloxane may be used in equimolar amounts or the amount by weight of each siloxane may be the same. Other suitable ratios (in terms of molar amounts or by weight of the total amount of siloxanes) when a mixture of two siloxanes are used range from 0.1 :99.9 to 99.9:0.1 , preferably from 1 :99 to 99:1, more preferably from 95:5 to 5:95, for example from 10:90 to 90:10 or from 25:75 to 75:25. For example, if a combination of hexamethyldisiloxane and octamethyltrisiloxane is used any ratio described above may be used. One particular combination comprises hexamethyldisiloxane: octamethyltrisiloxane in a ratio of 95:5.

In an aspect of the invention a composition comprising two or more siloxanes is used. For example, a composition comprising the combination of hexamethyldisiloxane and octamethyltrisiloxane can be used. If the composition comprises three silicone materials, the total siloxanes typically comprises from 0.1 to 99.8 % by weight of the total amount of siloxanes of each of the first, second, and third silicone material, preferably from 1 to 98 % weight of the total amount of siloxanes of each of the first, second, and third siloxanes, more preferably from 5 to 90 % weight of the total amount of siloxanes of each of the first, second, and third siloxanes, for example from 10 to 80 % weight of the total amount of silicone material of each of the first, second, and third siloxanes, such as from 25 to 50 % weight of the total amount of siloxanes of each of the first, second, and third siloxanes.

If the composition comprises four siloxanes, the total siloxanes typically comprises from 0.1 to 99.7% by weight of the total amount of siloxanes of each of the first, second, third and fourth siloxanes, preferably from 1 to 97% by weight of the total amount of siloxanes of each of the first, second, third and fourth siloxanes, more preferably from 5 to 85 % by weight of the total amount of siloxanes of each of the first, second, third and fourth siloxanes, for example from 10 to 70 % by weight of the total amount of siloxanes of each of the first, second, third and fourth siloxanes, such as from 20 to 40% by weight of the total amount of siloxanes of each of the first, second, third and fourth siloxanes.

If the composition comprises five siloxanes, the total siloxanes typically comprises from 0.1 to 99.6% by weight of the total amount of siloxanes of each of the first, second, third, fourth and fifth siloxanes, preferably from 1 to 96% by weight of the total amount of siloxanes of each of the first, second, third, fourth and fifth siloxanes, more preferably from 5 to 80 % by weight of the total amount of siloxanes of each of the first, second, third, fourth and fifth siloxanes, for example from 10 to 60% by weight of the total amount of siloxanes of each of the first, second, third, fourth and fifth siloxanes, such as 15 to 40% by weight of the total amount of siloxanes of each of the first, second, third, fourth and fifth siloxanes.

The compositions used comprise a polar solvent, component (iii). Suitable polar solvents include, but are not limited to, water, alcohols, esters, hydroxy and glycol esters, polyols and ketones, and mixtures thereof. Preferably, the polar solvent comprises or consists of water and optionally one or more of esters, hydroxy and glycol esters, polyols and ketones,

Suitable alcohols include, but are not limited to, straight or branched chain Ci to C₅ alcohols, such as methanol, ethanol, n-propanol, iso-propanol, mixtures of propanol isomers, n- butanol, sec-butanol, tert-butanol, iso-butanol, mixtures of butanol isomers, 2-methyl-1- butanol, n-pentanol, mixtures of pentanol isomers and amyl alcohol (mixture of isomers), and mixtures thereof. The compositions used in the invention typically comprise 1% by weight or less than 1% by weight, 0.5% by weight or less than 0.5% by weight or 0.1% by weight or less than 0.1 % by weight alcohol. In other words, the compositions used are typically substantially free of or free of alcohol.

Suitable esters include, but are not limited to, methyl acetate, ethyl acetate, n-propyl acetate, iso-propyl acetate, n-butyl acetate, iso-butyl acetate, sec-butyl acetate, amyl acetate (mixture of isomers), methylamyl acetate, 2-ethylhexyl acetate and iso-butyl isobutyrate, and mixtures thereof.

Suitable hydroxy and glycol esters include, but are not limited to, methyl glycol acetate, ethyl glycol acetate, butyl glycol acetate, ethyl diglycol acetate, butyl diglycol acetate, ethyl lactate, n-butyl lactate, 3-methoxy-n-butyl acetate, ethylene glycol diacetate, polysolvan O, 2- methylpropanoic acid-2,2,4-trimethyl-3-hydroxypentyl ester, methyl glycol, ethyl glycol, iso- propyl glycol, 3-methoxybutanol, butyl glycol, iso-butyl glycol, methyl diglycol, ethyl diglycol, butyl diglycol, iso-butyl diglycol, diethylene glycol, dipropylene glycol, ethylene glycol monohexyl ether and diethylene glycol monohexyl ether, and mixtures thereof.

Suitable polyols include, but are not limited to, ethylene glycol, propylene glycol, 1 ,3-butylene glycol, 1 ,4-butylene glycol, hexylene glycol, diethylene glycol, triethylene glycol and dipropylene glycol, and mixtures thereof. The use of compositions that are free of polyols, for example compositions that are free of propylene glycol is envisaged.

Suitable ketones include, but are not limited to iso-butyl heptyl ketone, cyclohexanone, methyl cyclohexanone, methyl iso-butenyl ketone, pent-oxone, acetyl acetone, diacetone alcohol, iso-phorone, methyl butyl ketone, ethyl propyl ketone, methyl iso-butyl ketone, methyl amyl ketone, methyl iso-amyl ketone, ethyl butyl ketone, ethyl amyl ketone, methyl hexyl ketone, diisopropyl ketone, diisobutyl ketone, acetone, methyl ethyl ketone, methyl propyl ketone and diethyl ketone, and mixtures thereof.

Typically, although not essentially, the compositions used do not comprise an ether. In a particular aspect, the compositions of the invention do not comprise dipropylene glycol methyl ether or propylene glycol n-butyl ether. Typically, although not essentially, the compositions used do not comprise an N- alkylpyrrolidone derivative. Preferred polar solvents for use in the compositions include, but are not limited to, water, diethylene glycol and dipropylene glycol and mixtures thereof. The compositions are typically substantially free of alcohol. By substantially free we mean that the compositions comprise less than 0.5% by weight alcohol. For example, the compositions may contain less than 0.5% by weight, for example less than 0.4% by weight, less than 0.3% by weight, less than 0.2% by weight or less than 0.1% by weight or less than 0.05% by weight of an alcohol such as ethanol, n-propanol or isopropanol or mixtures of alcohols. As an example, compositions free of an alcohol such as ethanol, n-propanol or isopropanol or mixtures of alcohols may be used.

In other aspects, the compositions used may comprise a mixture of water and one or more alcohols, such as ethanol, n-propanol, isopropanol. In such mixtures, water is preferably the major component, for example the amount of alcohol can be within the ranges discussed above or a higher amount of alcohol can be used. For example, in some aspects the compositions used may contain 40% or less by weight alcohol, for example no more than 20% by weight alcohol, preferably no more than 10% by weight alcohol, more preferably no more than 5% by weight alcohol.

It has been found that in use the wipes of the invention can provide an advantageous antimicrobial effect. For example, an enhanced kill rate can be achieved when they are used to treat a surface (so called "wet kill") and/or they can also provide a residual anti-microbial effect in that the formation of new microbial colonies at the surface is controlled, reduced or prevented (so called "dry kill") and/or they can provide an effective anti-microbial effect at significantly lower concentration of anti-microbial agent than previously known wipes.

The compositions used in the invention are also resistant to washing with water and to wiping. This means that the wipes of the invention provide a residual anti-microbial effect even when the surface which has been treated is subsequently wiped and/or washed or rinsed with water.

Typically, component (i) is present in the compositions used in an amount of from about 0.001 to about 50 % by weight of the compositions, such as from about 0.01 or about 0.02 to about 40 %, for example from about 0.05 to about 30 %, preferably from about 0.1 to about 20 % (e.g. from 0.2 to 15 % or 0.5 to 10 %). For example, anti-microbial agent(s), such as PHMB, may be present in the compositions used in an amount of from about 0.001 to about 20 % by weight of the compositions, such as from about 0.005 to about 5 % or about 10%, for example from about 0.01 to about 2 %, preferably from about 0.05 to about 1 % (e.g. from 0.1 to 0.5 %).

Typically, the component (ii) is present in the compositions in an amount of from about 0.001 to about 50 % by weight of the compositions, such as from about 0.002 to about 5 %, for example from about 0.003 to about 2 %, preferably from about 0.005 to about 1 % (e.g. from 0.008 to 0.8 % or 0.1 to 0.5 %).

Typically, the polar solvent component (iii) is present in the compositions used in an amount of from about 10 to about 99.999 % by weight of the compositions, such as from about 50 to about 99.999 %, for example from about 80 to about 99.99 %, preferably from about 90 to about 99.9 %, more preferably from about 95 to about 99.8 % (e.g. from 97 to 99.7 % or 97.5 to 99.6 %).

It will be appreciated that the actual concentration of components (i) and (ii) in a composition will depend on the intended use of that composition. For disinfecting uses, such as cleaning of hospital wards and equipment to help prevent the spread of disease such as MRSA, higher concentrations are required than for certain sanitising applications.

In use the wipes of the invention (ie the compositions contained on/in the substrate) may act to substantially reduce or control the formation of microbial colonies on or at the surface to which they are applied. This means that not only do these compositions kill any microorganisms that are present on a surface when they are applied to that surface (so called "wet kill"), they may also have a residual effect in that they can prevent the formation of new microbial colonies at the surface (so called "dry kill"). It is believed that in certain combinations the non-ionic surfactant and the antimicrobial agent(s) and the hydrophobic material (if used) may remain on the surface after the polar solvent has evaporated and that the presence of these components on the surface prevents bio-film formation/the growth of colonies of microorganisms. The residual effect can often be seen even after a treated surface has been washed or rinsed with water and sometimes even after numerous washings or rinsings.

Anti-microbial compositions are considered to have residual efficacy if, in the residual efficacy test described herein, they give a reduction in the number of microorganisms which is at least log 3.0. Preferably an anti-microbial composition having a residual effect and tested in this manner will give a log reduction of at least about 3.5, more preferably at least about 5.0 and most preferably about 7.0 or more, up to total kill or substantially total kill (zero survivors) under the test conditions described above.

In a particular aspect, the present invention provides wipes which provide a residual antimicrobial effect. By this we mean that when they are tested in accordance with the residual efficacy test described herein an anti-microbial efficacy within the parameters set out in the paragraph above is seen.

It has been found that the unique composition of the compositions used in the invention can result in increased anti-microbial efficiency (either in terms of higher initial rates of kill and/or in terms of residual efficacy) compared to the use of the anti-microbial agents alone. This is particularly surprising because the non-ionic surfactants used in the invention do not themselves have any anti-microbial properties. This means that the concentration of antimicrobial agent required by the invention to give the desired effect can be lower than that required in many conventional anti-microbial wipes. The prevention of the formation of a biofilm and the greatly reduced and attenuated colonies of microorganisms provides a substantially reduced risk due to infection or contamination.

The anti-microbial compositions used are typically able to break down biofilms that have already formed.

As the anti-microbial compositions used physically disrupt the adhesion and attachment of a microorganism to a surface, which is a feature that is common to a wide range of microorganisms, including bacteria, fungi and moulds, the compositions are effective against a broad range of microorganisms. Thus, an advantage of the invention is that the wipes can be used to prevent a broad range of microorganisms from adhering and attaching to the surface, and, therefore, from forming a biofilm. Large numerous colonies are also substantially prevented from forming. Thus, the ability of the colony to grow is substantially reduced or even prevented. The wipes of the invention are, therefore, typically general in their control of microorganisms. The anti-microbial compositions used do not comprise materials that produce highly persistent residues or rinsates or products that contain heavy metals and their salts. Thus, there is a greatly reduced risk of long term hazards associated with the anti-microbial compositions.

The compositions used do not interfere with the biochemical reproductive pathways of the microorganisms it controls. The risk of resistance build up and the development of resistant strains is, therefore, low. The compositions used and wipes containing them have a very good hand feel which makes them particularly suitable for uses such as hand sanitizing.

The present invention provides anti-microbial wipes suitable for a variety of consumer applications. For some applications the compositions described above may be incorporated into surfactant based formulations. These surfactant based formulations may comprise one or more surfactants in addition to the surfactants mentioned above. For example, they may comprise at least one non-ionic, anionic, cationic and/or amphoteric surfactant. In a particular aspect the formulation may comprise at least one non-ionic and/or amphoteric surfactant. However, formulations free of or substantially free of amphoteric surfactants are also envisaged. For example, formulations and compositions which comprise a polymeric biguanide such as PHMB may be free of or substantially free of amphoteric surfactants. Typically the formulations are free of or substantially free of anionic surfactant.

In one aspect, the compositions and formulations used in the invention do not comprise an isothiazalone.

Examples of the formulations containing a composition as described above which may be impregnated onto/into a substrate to provide a wipe of the invention include, but are not limited to, surface cleaners such as those intended for use in bathrooms, kitchens, living areas, hard floor cleaners, carpet cleaners, furniture cleaners, glass/mirror cleaners;

cleaning products intended for use outdoors such as those for cleaning for wood, stone, concrete or plastics, for example patio cleaner, garden furniture cleaners/treatments, BBQ cleaners, wall and fence cleaners/treatments,

personal care products such as hand sanitisers, deodorants and antiperspirants, skin care products such as shaving products, cosmetics and products for hair removal; baby products including baby cleaning and cleansing products such as baby wipes, products for cleaning surfaces that have regular & high incidence of infant & baby contact;

first aid products and products for treating ailments and illnesses, including products for the topical treatment and/or prevention of minor infections such as athletes foot, spot/acne prevention/treatment products;

foot hygiene products, including those for use on the foot and those for the treatment/deodourisation of foot ware, particularly sports foot wear;

products for cleaning and/or deordourising vehicles such as cars. Formulations which may be used to make products of the type described above typically comprise (A) at least one surfactant (referred to hereinafter as component (A) or the at least one formulation surfactant) and (B) an anti-microbial composition as described above.

The formulation surfactant (A) may be any suitable surfactant or combination of surfactants, for example at least one non-ionic, anionic, cationic and/or amphoteric surfactant. In a particular aspect of the invention the formulation surfactant (A) comprises at least one non- ionic and/or amphoteric surfactant. The selection of the formulation surfactants (A) will depend on the nature of and the intended purpose of the formulation. Suitable surfactants for use in formulations intended for different purposes will be within the knowledge of the person of ordinary skill in the art.

The pH of the compositions and formulations used can vary within wide limits, for example from about pH 2 to about pH 12, more preferably from about pH 3 to about pH 10 or about pH 4 to about 9.5 or 9 or 8.5. The pH of a formulation used in the invention may be similar to that of known formulations which are intended to be used for the same purpose or a similar purpose. For example, a formulation that is intended to come into contact with the skin such as a personal care or first aid formulations as listed above will typically have a pH which will not irritate the skin, for example from about pH 4.5 to about pH 8, such as from about pH 4.5 to about pH 7.5 or from about pH 4.5 to about pH 5.5.

On the other hand, formulations for use for purposes such as kitchen or bathroom cleaning may have a low pH, such as a pH of 3 or below, for example about 2; while other household cleaners may have a pH from 8 to 11 , for example 9 or 10. Some formulations used in the invention, which are intended for use as hard surface cleaners have a pH of from about pH 4 to about pH 9.5, for example from about pH 5 to pH 7 or 8. In one preferred group of formulations, the formulation surfactant (A) comprises at least one non-ionic surfactant. For example, the formulation surfactant (A) may consist essentially of at least one non-ionic surfactant or the formulation surfactant (A) may consist of at least one non-ionic surfactant. If the formulation surfactant (A) consists of at least one non-ionic surfactant it will not contain other types of surfactants, for example it will be free of amphoteric surfactants, anionic surfactants and cationic surfactants. Examples of non-ionic surfactants that can be used in these formulations are listed below.

In another preferred group of formulations, the formulation surfactant (A) is an amphoteric surfactant. Amphoteric surfactants can be used alone or in combination with a non-ionic surfactant. If a combination of an amphoteric surfactant and a non-ionic surfactant is used the weight ratio of the two types of surfactant can vary within wide limits, for example from 1% of amphoteric surfactant to 99% of non-ionic surfactant to 99% of amphoteric surfactant to 1 % of non-ionic surfactant, based on the total weight of the formulation surfactant (A). Preferably the amphoteric surfactant and the non-ionic surfactant are used in approximately equal amounts by weight.

In one aspect of the invention, preferred formulations comprise up to about 5% by weight (based on the total weight of the formulation) amphoteric surfactant, although higher levels of amphoteric surfactant can be used in some formulations. As an example, formulations may have a pH of from about 5 to about 8, more preferably from about 5 to about 7 and comprise an amphoteric surfactant and a non-ionic surfactant, wherein the amphoteric surfactant is present in an amount of up to about 5% by weight (based on the total weight of the formulation). In such formulations, the total amount of surfactant is not particularly limited and the total amount of surfactant may be an amount that is typical in the art for the particular type of formulation in question. Examples of preferred formulations comprising an amphoteric surfactant and a non-ionic surfactant have a total surfactant content of about 10% by weight, wherein no more that 5% by weight (based on the total weight of the formulation) is amphoteric surfactant.

Suitable cationic surfactants for use as the formulation surfactant (A) include but are not limited to di.stearyl dimethyl ammonium chloride, lauryl trimethyl ammonium chloride, alkyl trimethyl ammonium methosulfate, coco trimethyl ammonium chloride and cetyl pyridinium chloride. Suitable non-ionic surfactants for use as the formulation surfactant (A) include those described above in relation to component (ii) and include but are not limited to ethylene oxide/propylene oxide block polymers, polyethoxylated sorbitan esters, fatty esters of sorbitan, ethoxylated fatty esters (containing from 1 to 25 units of ethylene oxide), polyethoxylated C₈-C₂2 alcohols (containing from 1 to 25 units of ethylene oxide), polyethyoxytated C₆-C₂₂ alkylphenols (containing from 5 to 25 units of ethylene oxide), alkylpolyglycosides. Examples include but are not limited to nonyl phenol ethoxylate (9EO), Nonyl phenol ethoxylate (2EO), octyl phenol ethoxylate (10EO), Ci₂/Ci₄ synthetic ethoxylate (8EO), stearyl alcohol ethoxylate (7EO), cetostearyl alcohol ethoxylate (20EO), coconut fatty amine ethoxylate (10EO), sorbitan monolaurate ethoxylate, 80%PO/20%EO, coconut diethanolamide (shampoo foam booster), sorbitan monolaurate, sorbitan monolaurate 4EO, di-isopropyl adipate, alkyl poly glucosides, such as Ce^o, preferably C_8-i₀ alkyl glucosides, eg Surfac APG (D-Glucopyranose oligomers C_8-10 alkyl glucosides, CAS 161074-97-1, available from Seppic, UK), and cetostearyl stearate. Other suitable non-ionic surfactants include Neodol 25-7 (C12/15 alcohol 7 ethoxylate (EO), CAS 68131-39-5), Surfac LM90/85 (C12/15 alcohol 9 ethoxylate (EO), CAS 68131-39-5), Surfac 65/95 (C9/11 alcohol 6.5 ethoxylate (EO), CAS 68439-45-2), Tomadol PF9 (C9/11 alcohol 6.0 ethoxylate (EO), CAS 68439-46- 3), Surfac T80 Veg (Polysorbate 80, Polyoxyethylene sorbate mono oleate, CAS 9005-65-6), Tween 60 (Polysorbate 60, Polyoxyethylene sorbate mono stearate, CAS 9005-67-8), Tween 40 (Polysorbate 40, Polyoxyethylene sorbate mono palmitate, CAS 9005-66-7), Surfac T-20 (Polysorbate 20, Polyoxyethylene sorbate mono laurate, CAS 9005-64-5), Surfac PGHC (Hydrogenated Castor oil 40EO, CAS 61788-85-0), Ninol 49-CE (Coconut diethanolamide, CAS 68603-42-9). Preferred non-ionic surfactants include those sold under the names Tomadol and Neodol.

Suitable amphoteric surfactants for use as the formulation surfactant (A) include but are not limited to C₆-C₂o alkylamphoacetates or amphodiacetates (such as cocoamphoacetates), Cio-C₁₈ alkyldimethyl betaines, Ci₀-C-i₈ alkyl amidopropyldimethyl betaines. Examples include but are not limited to coconut amphoteric surfactant cocoamidopropyl betaine (CAPB) (Surfac B4, CAS 61789-40-9), coco imidazoline betaine, oleo amido propyl betaine, and tall oil imidazoline. Particularly preferred amphoteric surfactants are cocoamidopropyl betaine and C₆-C₁₄ alkylamidopropyl betaine.

Other suitable surfactants include those that exhibit non-ionic or cationic type properties at pHs below about 8, for example between about pH 5 and about pH 7 or 8. It will be appreciated that the behaviour of such surfactants depends on factors such as their pKa and which surfactants are suitable for use in a given formulation will depend on the pH of the formulations. Examples of surfactants which exhibit properties that can vary with pH and that can be used in the formulations of the invention include but are not limited to amine oxides such as those having an average carbon chain length of from 8 to 20, eg 12 or 14 such as Cio-C₁₈ alkyldimethyl amine oxides and C₈-C₂₂ alkoxyethyldihydroxyethylamine oxides, for example dimethyl laurylamine oxide (eg Surfac AO30 from Surfachem and manufactured by Stepan as Ammonyx LO), alkyl ether carboxylates and alkyl ether phosphates, such as those having an average chain length of from 8 to 12, eg 12 or 14 (eg Laureth 11 carboxylic acid, sold by Univar as Akypo RLM 100 and Laureth 4 phosphate, sold by Surfachem and manufactured by Schill and Seilacher as Silaphos DE 124). These surfactants can be used in combination with other surfactants such as non-ionic surfactants.

Preferred combinations of surfactants include but are not limited to CAPB and a non-ionic surfactant, such as an alcohol ethoxylate or an APG, an amine oxide and a non-ionic surfactant, such as an alcohol ethoxylate or an APG.

It will be appreciated that the compositions and formulations used the invention can comprise other ingredients commonly used in the art. The nature of any other ingredients used will depend on the nature and intended purpose of the composition or formulation. The person of ordinary skill in the art will know which additional ingredients are suitable for use in compositions and formulations for different applications.

Additional ingredients that may be used include but are not limited to water, antioxidants, thickeners, corrosion inhibitors, foam makers/boosters such as alkanolamides and amine oxides, eg alkyl amine oxides and ethoxylated amine oxides and breakers, abrasives, chelating agents such as tetrasodium EDTA, sequesterants such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), tetrasodium EDTA, other acetic acid derivatives and mixtures thereof, salts such as sodium chloride and citrate salts, pH modifiers, for example acids such as citric, sulfamic, hydrochloric, phosphoric, nitric, lactic, formic, acetic or gluconic acids or other mineral or organic acids or bases such as sodium or potassium hydroxide and mono-, di- or tri- ethanolamine, colorants, fragrances, emollients and skin rejuvenating and/or protecting agents.

Some compositions used are free of one or more of 2-({2- [bis(carboxymethyl)amino]ethyl}(carboxymethyl)amino)acetic acid (EDTA) and EDTA containing materials such as EDTA salts, chelating agents and citrate salts. These compositions are free of ethylenediaminetetraacetic acid (EDTA) and EDTA salts such as tetrasodium EDTA, and/or of citrate salts such as sodium citrate or potassium citrate. They may also be free of nitrilotriacetic acid (NTA), and/or other acetic acid derivatives and/or of metal ion sequestrants.

Some compositions and formulations are free of or substantially free of acids or bases. For example some compositions and formulations used do not comprise a citrate or citric acid or boric acid. Other compositions and formulations may contain an acid or base as is appropriate for their intended use.

For the avoidance of doubt, when we state herein that the formulations comprise a surfactant or is surfactant based we mean that the formulations comprise a surfactant in addition to the surfactant(s) present in the anti-microbial compositions of the invention used in those formulations.

It will be appreciated that the amount of formulation surfactant (A) in the formulations used will depend on factors such as the intended purpose of the formulation. Typically, the formulations comprise from 0.1 to 30 % by weight of formulation surfactant (A), preferably from 0.2 to 25 % by weight. For household cleaning products the amount of surfactant (A) is typically from about 0.1 to 10% by weight. For personal care products the amount of surfactant (A) is typically from about 0.1 to 20 % by weight for example from 15 to 20 % by weight. It will be appreciated that these percentages are examples only and that some products may comprise surfactant (A) in an amount outside the range specified for a given product type.

The anti-microbial compositions and formulations used can typically degrade when submersed in water, to provide a rinsate/leachate of low toxicity and which has a short residence time in the environment. According to a further aspect of the invention, there is provided the use of an anti-microbial wipe of the invention to prevent the formation of colonies of microorganisms on a surface at which it is provided.

The invention also provides a process for making the wipes of the invention. For example, a wipe of the invention can be made by impregnating a suitable substrate (preferable a substrate comprising a cellulosic material) with sufficient of an antimicrobial composition of the invention to produce a moist wipe.

The compositions used in the invention can be prepared by a process which comprises the steps of (A) mixing at least part of component (i) and component (ii); (B) adding the polar solvent to the mixture formed in step (A); and (C) agitating the resulting mixture until a clear solution is formed.

If component (i) is a solid, step (A) can be carried out in sufficient polar solvent to dissolve component (i). Alternatively, some materials which may be used as component (i) are commercially available in solution or emulsion. In this case, these materials can be used in step (A) in their commercially available form.

Typically, the mixture used in step (A) comprises from about 1 to about 25% by weight of a polar solvent, more preferably from about 2 to about 8% by weight polar solvent. The person of ordinary skill in the art could readily determine an appropriate amount of solvent to use. If too much solvent is used the initial cloudy solution will not become clear. The polar solvent typically used in step (A) is water, although other polar solvents may be used alternatively or additionally.

Typically, the process to produce the compositions is carried out at room temperature with stirring. In step (A) the mixture is initially cloudy because the component (ii) has limited solubility in the polar solvent. Typically step (A) is complete when the solution becomes clear. It is thought that this clear solution contains colloids or micelles of the components (i) and (ii).

In step (A) the components may be mixed in any manner suitable. This may be achieved by slow addition of a component (i) to component (ii) or visa versa and then mixing (for example stirring overnight). It would be a routine matter for the person of ordinary skill in the art to determine a suitable rate of addition. The mixing/blending steps can also use techniques such as ultrasonic mixing/blending.

The compositions used in the invention may be prepared in a concentrated form (i.e. with little or no polar solvent) and diluted with polar solvent (e.g. water) when used.

The following are non-limiting examples of compositions that may be used in the invention. A composition comprising an anti-microbial composition comprising (i) an anti-microbial component selected from (I) at least one, such as at least two, quaternary ammonium compounds, optionally in combination with a polymeric biguanidine, such as PHMB and (II) a polymeric biguanide, such as PHMB, optionally in combination with another anti-microbial agent, (ii) at least one non-ionic surfactant, (iii) at least one polar solvent, typically water. Preferably the non-ionic surfactant is an alcohol ethoxylate or APG such as one sold under the Tomadol or Neodol name. A composition comprising an anti-microbial composition comprising (i) an anti-microbial component comprising (I) at least one, such as at least two, quaternary ammonium compounds, optionally in combination with a polymeric biguanidine, such as PHMB and (ii) at least one non-ionic surfactant, (iii) at least one polar solvent, typically water' and (iv) at least one hydrophobic material, such as a polydimethylsiloxane. Preferably the non-ionic surfactant is an alcohol ethoxylate such as one sold under the Tomadol or Neodol name or an APG.

The following are non-limiting examples of formulations of the invention:

A formulation comprising: (A) at least one non-ionic surfactant; (B) an anti-microbial composition comprising (i) an anti-microbial agent selected from (I) at least one, such as at least two, quaternary ammonium compounds, optionally in combination with a polymeric biguanidine, such as PHMB and (II) a polymeric biguanide, such as PHMB, optionally in combination with another anti-microbial agent, (ii) at least one non-ionic surfactant, (iii) at least one polar solvent, typically water, optionally(iv) at least one hydrophobic material, such as a polydimethylsiloxane; and optionally other compatible ingredients as described above; the formulation preferably being substantially free of anionic surfactant. (A) may, for example, comprise one or more non-ionic surfactants only, ie such formulations do not comprise other surfactants such as amphoteric surfactants. A formulation comprising: (A) at least one non-ionic surfactant and at least one amphoteric surfactant provided that the total amount of amphoteric surfactant is 5% by weight or less based on the total weight of the formulation; (B) an anti-microbial composition comprising (i) an anti-microbial agent selected from (I) the combination of at least one, such as at least two, quaternary ammonium compound, and a polymeric biguanidine such as PHMB, and (II) a polymeric biguanide, such as PHMB, optionally in combination with another anti-microbial agent, (ii) at least one non-ionic surfactant (iii) at least one polar solvent, typically water, optionally (iv) at least one hydrophobic material, such as a polydimethylsiloxane; and optionally other compatible ingredients as described above; the formulation preferably being substantially free of anionic surfactant. A formulation having a pH of about 8 or less, such as from about 5 to about 8 and comprising: (A) at least one surfactant which exhibits non-ionic or cationic type properties at a pH below about 8; (B) an anti-microbial composition comprising (i) an anti-microbial agent selected from (I) the combination of at least one, such as at least two, quaternary ammonium compound, and a polymeric biguanidine such as PH B and (II) a polymeric biguanide, such as PHMB, optionally in combination with another anti-microbial agent, (ii) at least one non-ionic surfactant, (iii) at least one polar solvent, typically water; optionally (iv) at least one hydrophobic material, such as a polydimethylsiloxane; and optionally other compatible ingredients as described above; the formulation preferably being substantially free of anionic surfactant. (A) may, for example, comprise one or more non-ionic surfactants only, ie such formulations do not comprise other surfactants such as amphoteric surfactants.

The formulations can be made by introducing an amount of an anti-microbial composition as described above into a pre-prepared initial formulation. For example, an anti-microbial composition could be introduced into a suitable commercially available detergent composition.

Alternatively, the anti-microbial composition may be incorporated into a formulation by addition during one of the steps in the process for making the formulation (ie without the formation of an initial formulation).

The invention is illustrated by the following examples.

Testing Method: Evaluation of bactericidal activity using suspension test with Escherichia coli K12 O Rough H48

Residual Efficacy Testing using Escherichia coli K12 O Rough H48

The residual efficacy of the wipes/compositions of the invention may be tested according to the following method. The aim of the test is to evaluate the residual efficacy of products of the invention against Escherichia coli K12 O Rough H48 using typical household conditions.

Media and Materials 10 g tryptone +

LB is sterilized by

Luria broth (LB) 5 g yeast extract +

autoclaving.

10 g NaCI / L water

15 g agar +

10 g tryptone + LBA is sterilized by

Luria broth Agar (LBA)

5 g yeast extract + autoclaving.

10 g NaCI / L water

30 mL Tween 80 +

30 g saponine + NF is sterilized by

Neutralising solution (NF)

1 g histidine + autoclaving.

1 g cysteine / L water

10 g tryptone +

5 g yeast extract +

10 g NaCI +

Luria broth + LB+NF is sterilized by

30 mL Tween 80 +

Neutralising solution (LB+NF) autoclaving.

30 g saponine +

1 g histidine +

1 g cysteine / L water

Sterile desalted water

Sterilized by means of Millipore filter. Used with

Bovine albumin solution 3 % BSA other liquids in final concentration of 0.3 % BSA

Incubator 37 C

Stopwatch

Ceramic tiles, glazed (10 cm x 10 cm)

Professional Care Wipes

Drigalsky spatula

Vortex mixer

Variable pipette and sterile tips 100mm Petri dishes

300ml Flasks

Test Organisms

Escherichia coli K12 O Rough H48

The test organism was kept on LBA plates at 4°C. One colony was used to inoculate a 100ml Flask of LB and incubated at 37°C for 16 hours to reach stationary phase. For log phase cultures, 4ml LB were inoculated with one colony and incubated at 37°C for 16 hours. 1 ml of the bacterial suspension was then added to 100ml LB and grown to an OD₆₀o of approximately 0.375. Serial dilutions of each organism were then performed using LB and plated onto LBA plates to determine the number of colony forming units per ml.

Validation of Test Conditions

1. Validation of Selected Experimental Conditions

1ml of Bovine Albumin solution (BSA) was placed in a test tube with 1ml of bacterial test suspension containing approximately 3.0x10⁸ cfu/ml and incubated at the test temperature of 20°C for 2 minutes. At the end of this time 8 ml of LB was added. This mixture was incubated for the test contact time of 10 minutes. The solution was then diluted to 3.0x10³ and 3.0x10² cfu/ml. 0.1ml of these test solutions were pipetted in triplicate and plated on 12- 15mls of LBA, which is equivalent to 3.0x10² and 3.0x10¹ cfu. The plates were incubated at 37°C for 24 hours. Test result should be equal to or greater than 0.05 times bacterial suspension.

2. Neutraliser Toxicity Validation

9ml of Neutraliser (NF) was placed in a test tube and mixed with 1 ml of a bacterial suspension containing approximately 3.0x10⁸ cfu/ml. The mixture was incubated at 20°C for 10 minutes. The suspension was diluted to 3.0x10³ and 3.0x10² cfu/ml using LBA. 0.1 ml was then pipetted onto triplicate plates containing 12-15mls of LBA. The plates were incubated at 37°C for 24 hours. Test result should be equal to or greater than 0.05 times bacterial suspension. 3. Dilution- Neutralisation Validation

1 ml of Bovine albumin solution (BSA) was placed in a test tube with 1 ml of LB and incubated at 20°C for 5 minutes. 1ml was then taken and added to 8ml Neutraliser (NF). After 5 minutes incubation, 1ml of the bacterial suspension was added. The mixture was left at 20°C for 10 minutes. The suspension was diluted to 3.0x10³ and 3.0x10² cfu/ml using LB and

0.1 ml was then plated in triplicate onto 12-15mls of LBA. The plates were incubated at 37°C for 24 hours. Test result should be equal to or greater than 0.5 times of Neutraliser Toxicity Validation.

Test Method

1. Pretreatment of Carrier

Carriers were cleaned / disinfected with isopropanol (70 % v/v) by spraying. Excess isopropanol was used to cover the entire surface completely. Excess isopropanol was removed by running off. Further drying was allowed for a period of 10 minutes.

2. 1^st Inoculation of Carrier

1^st challenge of tile surface with ~10⁶ CFU bacteria. Application volume is set at 10 μΙ_. If residual amounts of isopropanol remain some of applied bacteria might be killed. The applied volume of 10 pL was spread over entire tile surface by means of sterile plastic spatula (Drigalsky spatula). Challenged tile is allowed to dry over a period of 50 minutes.

3. Product Application to Carrier

1 mL of disinfecting product was applied to a pretreated carrier surface. Applied disinfecting product was spread over entire surface by means of sterile plastic spatula (Drigalsky spatula). Surface treatment with excess disinfecting product was done over a period of 10 minutes. Pretreated carriers were stored overnight in a clean place, covered with Professional Care Wipes. 4. inoculation of Carrier

Inoculation of tile surface was done by using ~10⁶ CFU bacteria. Application volume was set at 10 pL. If residual amounts of isopropanol remain some of applied bacteria might be killed. The applied volume of 10 pL was spread over entire tile surface by means of sterile plastic spatula (Drigalsky spatula). Challenged tile was allowed to dry over a period of 50 minutes.

5. Rinsing with Water

Tile surface was rinsed with 10 mL sterile water (water_mj|iipo_red). After rinsing tile was dried for up to 1 hr or till surface was visibly dry. 6. Dry wear cycle Wear cycles are used as an abrasive step. A dry wear cycle was done by moving a cork block wrapped with Professional Care Wipe back and forth. Normal hand pressure was applied. Professional Care Wipes of non viscose type, do not adsorb quaternary ammonium compounds or PHMB.

7. Wet Wear Cycle

Wetting of Professional Care Wipes was done by spraying water_mi|ijpored onto wipes. Spraying was done by triggering one time from about 30 cm. Wet wear cycles were used as an abrasive step. A Wet wear cycle was done by moving a cork block wrapped with wetted (water_miiiipored) Professional Care Wipe back and forth. Normal hand pressure was applied. The wetted surface was allowed to dry for at least 10 minutes.

8. Final Inoculation of Carrier

The tile is challenged with ~10⁶ CFU bacteria. The application volume was set at 10 pL. The applied volume was spread over entire tile surface by means of sterile plastic spatula

(Drigalsky spatula). The challenged tile was allowed to dry over a period of 5 to 10 minutes.

Surviving bacteria were dissolved by applying 500 μΙ_ LB + NF. The applied LB + NF was spread over entire tile surface by means of sterile plastic spatula (Drigalsky spatula, single use version). The neutralizer had no killing effect on surviving bacteria, but inactivates the disinfecting product on tiles. To dissolve surviving bacteria the tile was incubated at room temperature for 30 minutes. Dissolved surviving bacteria were collected by means of sterile plastic spatula (Drigalsky spatula).

9. Determination of Survivors

The collected liquid was sampled by means of a sterile pipette. 100 pL of sample was applied to 900 pL of LB + NF. Serial dilution in LB + NF up to 10^"* 100 pL of sample was carried out and the dilutions are transferred to agar plates.

Test Method - Total Procedure

# DAY PROCEDURE

1 1 Preparation of bacteria culture (overnight culture)

2 Pretreatment of carrier (tiles); see Step 1

3 1^st Inoculation of Carrier; see Step 2

4 Product Application to Carrier; see Step 3

5 Wet wear cycle; see Step 7 Dry wear cycle;; see Step 6

Rinsing with water_mj|iip_0red ; see Step 5

Inoculation of carrier; see Step 4

Dry wear cycle; see Step 6

Final inoculation of carrier; see Step 8

Determination of survivors; see Step 10

This test procedure uses 10⁸ CFU/mL This means that a log 8 reduction in the number of micro-organisms is equivalent to zero survivors.

Using this test procedure, compositions which have a residual efficacy can be identified. Anti-microbial compositions are considered to have residual efficacy if, in this test, they give a reduction in the number of micro-organisms which is at least log 3.0. Preferably an antimicrobial composition having a residual effect and tested in this manner will give a log reduction of at least about 3.5, more preferably at least about 5.0 and most preferably about 7.0 or more under the test conditions described above.

Materials Used

PHMB Vantocil TG from Arch Chemicals.

Neodol Shell Neodol 91-5 and 91-8 from Surfachem.

Tomadol Tomadol 900 from Tomah (US).

APG Surfac APG PC (personal care grade) purchased from Surfachem,

BAC Thor Acticide BAC50M.

DDQ Bardac 2240 from Lonza.

Natrosol Natrosol 250HR from Aqualon (Hercules)

Reference Example 1 - Preparation of the Anti-microbial Composition G5

Step 1

Mason Quat MQ624M was mixed with 3.85% by weight of 3cSt(Byotrol) silicone (Clearco) and stirred at room temperature for a minimum of 30 minutes. The resulting mixture was clear and was left a further 12 hours.

Step 2 To 130g of the product of step 1 was added 500g of Vantocil TG (UK) or Vantocil P (US) and 370g of Water. This is stirred at room temperature for 30 minutes to completely dissolve the Vantocil. These steps produced the anti-microbial composition, G5, which comprised 10% by weight quaternary ammonium compounds, 10% by weight PHMB and 0.5% by weight silicone.

Example 2 - Testing of the G5 Formulation in Combination with Various Non-Ionic Surfactants

Tests were carried out to determine the resistance to quaternary ammonium compound depletion on contact with a viscose or viscose-containing cloth of the G5 formulation when combined with a non-ionic surfactant. A known weight of substrate was impregnated at the 300% by weight level with an impregnating composition containing 1% G5 Concentrate plus the non-ionic surfactant additive. After storage in a sealed container for 3 to 5 days the excess liquid was expelled from the impregnated substrate. The total titratable cationic antimicrobial contents of the initial liquid composition and the expelled liquid were determined by the two-phase mixed indicator titration procedure (Reid et al. Tenside 4 (1967) 292) using an average molecular weight of 369.

All samples were conducted with 1% G5 (lOOOppm quats) on a 50gsm 40:60 viscose: polyester spunlaced blend substrate.

The results of these tests are shown in the table below.

Table 1 Quaternary ammonium compound depletion from supernatant liquid by viscose/polyester substrate

Formulation Quat Non-ionic surfactants

Depletion

G5 + Emulgade CM 0% Ceatereth-12 and ceatereth-20 etc.

G5 + Tegosoft GMC6 5% PEG-6 caprylic/capric glycerides

G5 + Tegosoft GC 2% PEG-7 glyceryl cocoate

G5 + Tegosoft PC41 20% Polyglyceryl-4 caprate

G5 +Tegosoft CT + 6% Caprylic/capric triglyceride + HCO

PEG25HCO ethoxylate ester

G5 + Tegosoft TN + 4% C 12-15 alkyl benzoate + HCO

PEG40HCO ethoxylate ester

G5 + PEG25HCO 7% HCO Ethoxylate ester G5 + Laureth-23 4% Alcohol ethoxylate

G5 + Laureth-7 1% Alcohol ethoxylate

G5 41% none

PEGxHCO are ethoxylates(x) of hydrogenal ted castor oil

Tegosoft products are manufactured by Degussa and EmulgadeCM from Cognis is a mixture of cetearyl isononanoate, ceteareth-20, cetearyl alcohol, glyceryl stearate, ceteareth- 12, cetyl palmitate and glycerol.

The ratio of non-ionic surfactan quaternary ammonium compound used was around 100:1 in each case.

The results in the table above show that when G5 was combined with a non-ionic surfactant, the resulting solutions were resistant to quaternary ammonium compound depletion on contact with viscose or viscose containing cloths.

Claims

1. An anti-microbial wipe comprising a substrate comprising from 1 to 100% by weight of a cellulosic material and incorporating a composition comprising (i) an anti-microbial component; (ii) a non-ionic surfactant; (iii) a polar solvent; and optionally (iv) a hydrophobic material; wherein the anti-microbial component (i) comprises (a) at least one quaternary ammonium compound of formula (A)

wherein R₂, R₃ and R₄ represent, independently a substituted or unsubstituted and/or straight chain or branched and/or interrupted or uninterrupted alkyl, aryl, alkylaryl, arylalkyi, cycloalkyi, heterocyclyl or alkenyl group, and wherein the total number of carbon atoms in the groups R_{1 t} R₂, R3 and R₄ is at least 4;

wherein the substituents for the groups R₁₍ R₂, 3 and R4 are selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, heterocyclyl, substituted heterocyclyl, cycloalkyi, substituted cycloalkyi, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyi, substituted arylalkyi, F, CI, Br, I, -OR', -NR'R", -CF_3> -CN, -N0₂, -C₂R\ - SR\ -N₃, -C(=0)NR'R", -NR'C(=0) R", -C(=0)R', -C(=0)OR', -OC(=0)R', -0(CR'R")_rC(=0)R\

-OC(=0)NR'R", -NR'C(=0)OR", -S0₂R', - S0₂NR'R", and -NR'S0₂R";

wherein R' and R" are individually hydrogen, C C₈ alkyl, cycloalkyi, heterocyclyl, aryl, or arylalkyi, and r is an integer from 1 to 6, or R' and R" together form a cyclic functionality; wherein the term "substituted" as applied to alkyl, alkenyl, heterocyclyl, cycloalkyi, aryl, alkylaryl and arylalkyi refers to the substituents described above, starting with F and ending with -NR'S0₂R";

and wherein X^" is halide or sulphonate;

and optionally (b) one or more additional anti-microbial agents, and wherein the composition is substantially free of anionic surfactant.

2. A wipe according to claim 1 , wherein the substrate comprises from 10 to 100% by weight of a cellulosic material.

3. A wipe according to claim 1 or 2, wherein the cellulosic material is viscose.

4. A wipe according to any one of the preceding claims wherein the substrate comprises viscose blended with polyester or polypropylene.

5. A wipe according to any one of the preceding claims, wherein the non-ionic surfactant comprises at least one non-ionic surfactant selected from ethylene oxide/propylene oxide block polymers, fatty esters and amides, alkylpolyglycosides and polyalkoxylated derivatives of general structure R(OCHXCH₂)_nOH, where R is derived from an alcohol, phenol, carboxylic acid, ester, amine or amide, X is independently H or CH₃and n is from 1 to 50.

6. A wipe according to claim 5, wherein the non-ionic surfactant comprises at least one non-ionic surfactant selected from alcohol ethoxylates and ethoxylated esters having from 2 to 15 ethoxylated units.

7. A wipe according to any one of the preceding claims wherein the anti-microbial component comprises at least two quaternary ammonium compounds.

8. A wipe according to any one of the preceding claims in which the anti-microbial component comprising a component (b) which is at least one polymeric biguanidine.

9. A wipe according to any one of the proceeding claims, wherein the compound of formula (A) has the formula (Α') (CH₃)_n(A)_mN⁺X^',

wherein each A is independently as defined for R_{1 (} R₂, R₃ and R₄, n is from 1 to 3 and m is from 1 to 3 provided that the sum of n and m is 4.

10. A wipe according to any one of claims 1 to 9, wherein the quaternary ammonium compound is selected from Cetrimide, dodecyltrimethyl ammonium bromide, tetradecyltrimethyl ammonium bromide, and hexadecyltrimethyl ammonium bromide.

11. A wipe according to any one of claims 1 to 8, wherein the quaternary ammonium com ound is a benzalkonium halide of formula:

wherein R is as defined for R^ R₂, R₃ and R₄ or an aryl ring substituted derivative thereof.

12. A wipe according to any one of the preceding claims which does not comprise a quaternary ammonium compound in which one or more of R¹, R², R³ and R⁴ are interrupted by a heteroatom.

13. A wipe according to any one of the preceding claims, wherein n is from 1 to 8.

14. A wipe according to any of the preceding claims wherein the polar solvent comprises water, and optionally one or more of an ester, an hydroxy and/or glycol ester, a polyol or a ketone.

15. A wipe according to any one of the preceding claims in which the composition comprises 0.5 % by weight or less of alcohol.

16. A wipe according to claim 15, which is free of an alcohol.

17. A wipe according to any one of the preceding claims that is free of one or more of EDTA, EDTA containing materials, chelating agents and citrate salts.

18. The use of a wipe according to any one of the preceding claims to provide an antimicrobial effect to a surface treated with the wipe.

19. The use of a wipe according to any one of claims 1 to 17 to substantially reduce or control the formation of microbial colonies on or at a surface.

20. A wipe as generally as herein described with reference to the Examples.