WO 2015/006801 PCT/AU2014/000718 1 Improved Bio-Repellent Hygiene System Technical Field [0001] This invention relates to a process for inhibiting the build-up of infectious material on a surface. More particularly this invention relates to a process for controlling the spread of infection on a surface, in particular a hospital acquired infection. Background of Invention [0002] More than a century after the discovery of the first successful disinfectant/ antiseptic, science has yet to find an effective answer to the ever growing persistent problem of contagious, potentially fatal, Hospital Acquired Infection (HAI). [0003] Control over the distribution of highly infective bacteria and other infective microorganisms throughout modern hospitals remains the greatest challenge to the efficient administration and operation of all classes of health care institutions. This is a worldwide problem resulting from multiple well described causes, not the least of which is the misuse and overuse of antibiotic drugs and the inefficient use of available means of chemical control. [0004] Controlling the ever increasing spread of HAl, also referred to in literature as Nosocomial Infections, is compounded by the recurring appearance of newer classes of highly infective pathogens that may cause either fungal, bacterial, viral or prion infectivity. Examples of more recently emerged pathogens found in hospitals are MRSA, Methicillin Resistant Staphylococcus aureus, VRE, Vancomycin resistant Enterococcus, and Clostridium difficile. Their importance derives from a combination of evolving resistance to antibiotics and biocides and that they have the propensity to rapidly spread through the residential patient environment, containing sick patients. These emerging pathogens invariably cause high mortality rate and expenditure of expensive more specialised medications. [0005] The organism C Difficile currently defies challenge by existing classes of chemical disinfectants and cleaner/disinfectants. It now occurs more frequently resulting from prolonged use of antibiotics acquired during treatment and antibiotic WO 2015/006801 PCT/AU2014/000718 2 resistance throughout populations. The only generally agreed chemical disinfectant that can eliminate populations of C Difficile spores in hospitals is to apply a solution of 50000ppm (5%) chlorine as sodium hypochlorite and maintain the surface wetted with the solution for one minute. This procedure is hazardous to personnel and surfaces and is not practical for general use in hygiene maintenance of healthcare institutions (Role of the hospital environment in disease transmission with a focus on C difficile: William Rutala et al. Health Infection 2013, 18, 14-22). [0006] A program for measuring the effectiveness of cleaning hospital procedures is that outlined in US Patent 20060223731 to P.C. Carling. This patent describes the many surfaces in hospitals, classified as "touch surfaces", which it groups into two categories - "low touch" where minimal contact occurs in the daily operations of hospital areas, and "high touch" where surfaces are routinely touched by both patients and hospital staff, the latter being found to be major reservoirs of HAI and therefore priority surfaces for frequent, effective, cleaning and disinfecting. [0007] Carling's process was evaluated in 2011-2 as an initial indicator of cleaning effectiveness as part of a research program in a large public hospital in Sydney, Australia. Total effectiveness of cleaning was measured by swabbing freshly cleaned surfaces to determine the type and number of retained pathogens. [0008] Surfaces involved in this trial were first subjected to "terminal cleaning" comprising an initial clean with a neutral detergent followed by terminal disinfection employing 500 ppm chlorine (Diversol, Johnson Diversey, Smithfield, Australia) the latter product being internationally promoted for high level hospital disinfection. Surfaces terminally cleaned in this carefully controlled research program were analysed by Scanning Electron Microscope, SEM. This revealed biofilms containing the different virulent multi resistant organisms, MRO, on all surfaces tested. [0009] All touch surfaces tested contained serious pathogenic microbes, within biofilms remaining after the internationally recommended terminal cleaning process. These results demonstrate beyond doubt the ineffectiveness of currently practiced procedures for terminal cleaning and, indeed, regular cleaning and disinfecting in hospitals, particularly after discharge of sick patients from wards. Current cleaning WO 2015/006801 PCT/AU2014/000718 3 processes fail to remove biofilms containing virulent pathogenic organisms therefore failing as a means of effective microbial control. [0010] A critical finding from this research was that oxidising types of chemical disinfectants, employing 500 ppm of active chlorine at use dilution for terminal disinfectant, fail to adequately clean and disinfect common touch surfaces built into modern hospitals. Prevention of transfer of resident pathogens under currently recommended hospital hygiene procedures is clearly not being achieved; and is, unquestionably, a significant contributor to increasing problems of HAI. [0011] The existence and significance of bacterial biofilms has been widely reported over the past two decades. A biofilm is a structured community of organisms encased and securely attached to a surface by exopolymeric substances (EPS). The EPS makes up to 90 percent of the biofilm forming protection from environmental desiccation. These films are difficult to remove by commonly used detergents and common chemical disinfectants recommended for hospital cleaning and general environmental hygiene. [0012] Most importantly, bacteria within biofilm are up to 250-500 times more resistant to biocides than the same bacteria growing freely in a liquid culture. In the biofilms, bacteria endure for extended periods in hostile conditions and are unrecognisable without special microbial examination, as, for example, by electron microscopy or atomic force microscopy. [0013] Biofilms can generally be found in moist environments resulting in infection on implanted medical devices such as catheters and breast implants, as well as surgical instruments routinely immersed in fluids. It is now found that despite decreased moisture availability on dry surfaces, bacteria can reside for extended periods in biofilms whereby medically resistant organisms are protected from physical and chemical disinfection. [0014] Microbes adhere to surfaces by means of exudates from the exterior membrane of vegetative cells, usually in the form of long protrusions composed of exopolysaccharide, commonly referred to as lipopolysaccharide, that possess highly effective adhesive properties. These filament-like exudates bond to surfaces serving WO 2015/006801 PCT/AU2014/000718 4 as anchors for the cell. This can occur with virtually every solid surface in its natural state. [0015] Recent research has demonstrated that it is the specific chemical characteristics of the surface chemistry that dictate whether or not a bacterial cell can attach to a surface. [0016] Bacteria have the ability to sense and respond to their environment. It is also possible that bacterial populations collectively respond to adjacent surfaces by quorum sensing (bacterial cell to cell communication) within their immediate environment. This may also be the consequence of individual cells sensing the nature of surrounding surfaces by their cell-associated proteins, or by specific cell associated structures such as flagella or pilli. [0017] The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application. [0018] It would be desirable to provide an improved method for inhibiting the formation of biofilms on surfaces in healthcare and other facilities, since current disinfection procedures have been disclosed inadequate. The present invention is directed to achieving this by depositing on such surfaces, in particular "touch surfaces", an ultrathin film, the characteristics of which inhibit the adhesion of microbes and soils, such as those found in healthcare facilities. This inhibits biofilm formation. Soiling and microbial matter may then be removed by cleaning. The process of the invention is intended to reduce the dependence on current generation chemical disinfectants, which are now recognised as fallible tools for infection control. Summary of Invention [0019] According to a first embodiment of the invention, there is provided a process for inhibiting build-up of infectious material on a surface, comprising applying to said surface a film forming composition comprising: WO 2015/006801 PCT/AU2014/000718 5 at least about 50% w/w of a liquid polymeric silicone, at least one first surfactant, wherein said first surfactant is hydrophobic, and at least one biocide; to form a film on said surface, and cleaning said film with a detergent composition comprising at least one second surfactant, said second surfactant yielding in aqueous solution an air/water surface tension of less than about 24 dyne/cm. [0020] According to a second embodiment of the invention, there is provided a process for inhibiting build-up of infectious material on a surface, said process comprising the steps of: a) applying to said surface a film forming composition comprising: at least about 50% w/w of a liquid polymeric silicone, at least one first surfactant, wherein said first surfactant is hydrophobic, and at least one biocide; to form a film on said surface; b) cleaning said film with a detergent composition comprising at least one second surfactant; and c) applying a maintainer composition, said maintainer composition comprising a small amount of said film-forming composition and at least one third surfactant; wherein said second and third surfactants yield in aqueous solution an air/water surface tension of less than about 24 dyne/cm. [0021] According to a third embodiment of the invention, there is provided a process according to the second embodiment comprising the further step of: d) substantially removing remaining film from said surface with said detergent composition; and optionally, repeating steps a to d. [0022] According to a fourth embodiment of the invention, there is provided a composition for inhibiting build-up of infectious material on a surface, said composition comprising at least two parts: WO 2015/006801 PCT/AU2014/000718 6 a first part comprising at least about 50% w/w of a liquid polymeric silicone at least one first surfactant, wherein said first surfactant is hydrophobic; and at least one biocide; and a second part comprising a detergent composition comprising at least one second surfactant, said second surfactant yielding in aqueous solution an air/water surface tension of less than about 24 dyne/cm. [0023] According to a fifth embodiment of the invention, there is provided a composition for inhibiting build-up of infectious material on a surface, said composition comprising: a) a film forming composition comprising at least about 50% w/w of a liquid polymeric silicone; at least one first surfactant, wherein said first surfactant is hydrophobic; and at least one biocide; b) a detergent composition comprising at least one second surfactant; and c) a maintainer composition comprising a small amount of said film forming composition and at least one third surfactant; said second and third surfactants yielding in aqueous solution an air/water surface tension of less than about 24 dyne/cm. [0024] Where the terms 'comprise', 'comprised' or 'comprising' are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components, or group thereof. [0025] In the context of this invention, a "biocide" is taken to mean a chemical that will kill, inactivate or repel living or replicating organisms. The term "living or replicating organisms" is taken to encompass living or replicating viruses, bacteria, fungi, yeasts, moulds, insects (for example, ants, bed bugs, cockroaches), arachnids (for example, spiders, mites such as dust mites,) and other vermin that can impact on the welfare of people.
WO 2015/006801 PCT/AU2014/000718 7 Detailed Description The film forming composition [0026] The first part of the process of the invention is to apply to a surface a very thin layer of a water repellent, hydrophobic film forming composition, which then forms a film on the surface. The film which is formed is preferably inert, non-toxic, non irritant, odourless, oxidation stable, durable, yet capable of being easily removed when required, repellent to chemicals commonly found in detergents and disinfectants, these properties making it well-suited for use in a health-care facility. It is also preferable that the film be environmentally safe. [0027] Preferably, the film does not provide a nutrient food source for pathogenic microbes, in the unlikely circumstance that adhesion of microbes to the film occurs, thereby inhibiting biofilm formation. [0028] Water repellents include polysiloxanes or polytetrafluorohydrocarbon. These have low surface free energy. For the purposes of this invention, liquid polymers of moderate molecular weight are preferred. Liquid fluorinated polymers are not environmentally friendly and may have health hazards. Polydimethylsiloxanes are suitable for the present invention. Liquid silicone CAS 63148-62-9 has excellent exterior durability and is environmentally friendly and is therefore preferred for the composition of the invention. [0029] The film forming composition of this invention comprises at least about 50 percent of a liquid polymeric silicone, preferably polydimethylsiloxane. To this is added a small quantity of at least one hydrophobic surfactant, that will increase the hydrophobicity of the silicone by further increasing the interfacial surface tension of the polymeric silicone to aqueous liquids, thus further increasing the repellency of the silicone film to normal hospital soils, including microbial fouling. Preferably the silicone is present in an amount of about 50 - 95% w/w, more preferably about 65-85% w/w, of the film forming composition. [0030] The at least one first surfactant used in the film forming composition increases the hydrophobicity of silicone fluid, and is generally of a type acceptable on WO 2015/006801 PCT/AU2014/000718 8 health and environmental grounds. It increases the interfacial tension of silicone fluid and increases penetration into surfaces, in particular semi-porous or rough surfaces. [0031] Preferably the first surfactant is selected from the group consisting of a dimeric surfactant, such as a Gemini (bis- or double tailed) siloxane surfactant, a fluorosurfactant (such as a DuPont CapstoneTM surfactant), a C8-C20 linear, unsaturated or branched chain fatty acid, reacted with a monovalent ion, preferably a sodium or potassium ion, or divalent metal ion; an ester of citric, lactic, propionic or maleic acid with a C2-C1 0 alcohol; a block polymer of one or more of ethylene oxide, propylene oxide and/or butylene oxide. [0032] Most preferably the first surfactant is hydrophobic. [0033] In one embodiment, the first surfactant is a Gemini surfactant, for example, the commercially available EnviroGem ADO1T '(Air Products), or a Capstone fluorosurfactant. In an alternative embodiment the first surfactant is a block copolymer based on ethylene oxide, propylene oxide and/or butylene oxide, preferably ethylene oxidelpropylene oxide block copolymers, of which the Pluronic range (BASF), such as Pluronic 31R1I T, are examples. [0034] Particularly preferred as first surfactants are EnviroGem ADO1 TM (Air Products Inc), having an HLB value 4, and Pluronic 31 R1 TM, having an HLB value of 2 to 7. [0035] Preferably, the first surfactant is present in an amount of about 0.5 to 8% w/w, more preferably about 1 to 6% w/w, of the film forming composition. [0036] The film forming composition further comprises a small quantity of at least one biocide, as hereinbefore defined. In one embodiment, a wide spectrum biocide is used, intended as further preventative of biofilm formation on surfaces, in the unlikely event that exopolysaccharride of a microbe or an undefined species makes contact with the film applied to the surface, thus inhibiting the growth of biofilm. [0037] Most preferably, the biocide is a hydrophobic biocide. [0038] Biocides suitable for use in the film are preferably water insoluble to avoid the possibility of leaching from the film during cleaning and disinfecting with aqueous WO 2015/006801 PCT/AU2014/000718 9 solutions. The biocides should be soluble in polydimethylsiloxane and be broad spectrum, to repel living or replicating organisms encountered in healthcare in normal use. [0039] The biocide use in the film forming composition may be selected from the group consisting of a phenolic biocide, organic divalent metal compound, silane biocide, chemicals described as 'repellents', and mixtures thereof. [0040] Phenolic biocides which may be used in the film forming composition are selected from the group consisting of 2,4,4'-trichloro-2'-hydroxydipheny ether (Triclosan
TM
); 2,4 dimethyl phenol; 4-tert-amylphenol; 2- benzyl-4- chlorophenol; p chlorophenol ; p-chloro-m-cresol; p-chloro-m-xylenol; tert-amyl-o- bromophenol; 2,2 methyl methylene bis (3,4,6-trichlorophenol); o-phenylphenol; a polyalkyl halophenol; and mixtures thereof. A preferred phenolic biocide is p-chloro-m-xylenol. [0041] Preferably the organic divalent metal compound is an organo-zinc compound. Most preferably, the organic divalent metal compound is selected from the group consisting of, but not limited to, zinc pyrithione, zinc acetate, zinc lactate, zinc octoate; and mixtures thereof. [0042] In an alternative embodiment, the biocide may be a silane biocide, such as 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (CAS 27668-52-6) or chloropropyltrimethyoxysilane (CAS 2530-87-2); and mixtures thereof. Other biocidal silane molecules exist that may exhibit useful biocidal properties and are not excluded, providing that each molecule is compatible with the composition used in the process of the invention. [0043] In a preferred embodiment of the invention, chemicals described as 'repellents', for example insect repellents, may be incorporated as biocide in the compositions of the invention. These particular chemicals work as repellents because of the slow, but adequate level of vapour found in the immediate vicinity of the surface to which they are applied. The chemical nature of the vapour layer proves hostile to the cells of organisms seeking attachment to a surface. The vapour layer is non conductive and, being negative ionically, prevents entry of positively charged groups on bacterial cells contacting surfaces treated with the repellent coatings of this invention. In this preferred embodiment, there are thus two distinct barriers inhibiting WO 2015/006801 PCT/AU2014/000718 10 attachment by organisms to treated surfaces - firstly a hostile vapour barrier and secondly a coating of hydrophobic ingredients that are repellent for reason of low surface energy and hydrophobicity. In this embodiment, the inclusion of the repellent in the composition of the invention is a further form of protection against attachment of living or replicating organisms and possible biofilm formation on surfaces. [0044] Preferably the repellents may be selected from the group consisting of naphthalene, paradichlorbenzene, camphor, dialkyl(C1-5) esters of phthalic acid, pyrethrum, diethyl toluamide(DEET), n-octyl bicycloheptene dicarboxamide, di-n propyl isochinchomeronate, imiprothrin, deltamethrin, permethrin, bioresmethrin, bifenthrin, BioallethrinTM (Sumitomo Chemical Pty Ltd), and terpenes. [0045] Particularly preferred as repellents are dimethyl phthalate and pyrethrum. [0046] Preferably the biocide is present in an amount of about 0.1 to 10%w/w, more preferably about 0.2 to 5% w/w, of the film forming composition. Typically, the film forming composition is diluted at use and the biocide is present in the range about 50ppm to 1 000ppm at use dilution. [0047] Optionally, a fluorescent dye may be included in the film forming composition. Preferably, the dye is strongly fluorescent to ultraviolet light. The dye will serve as a visual indicator of the effective presence of the film. A wide range of organic fluorescing agents are available for this purpose. Those used in flaw or crack location fluids for use on engineered parts, and optical brighteners used in laundry detergents, are particularly suitable. Biocides exhibiting this useful phenomenon may also be employed, for example salicylanilide and related amine and imine derivatives of salicylic acid. As low as about 1Oppm by weight of the fluorescent dye may be sufficient to provide strong visual indication of presence. [0048] A small quantity of a water-miscible solvent or solubilizing agent (hydrotrope) may also be added to the film forming composition to solubilise particular surfactants and biocides into the concentrated film. It also facilitates penetration into and dispersion of biofilm EPS. After application of the film-forming composition, the solvent evaporates, leaving the film on the surface which is to be protected.
WO 2015/006801 PCT/AU2014/000718 11 [0049] Preferably the solvent or solubilizing agent is selected from the group consisting of a C2-C8 aromatic alcohol or C2-C10 glycol and C1-C6 esters thereof; a nitrogen containing compound having less than 9 carbon atoms, and mixtures thereof. More preferably the solvent is selected from the group consisting of ethanolamines pyrrolidone; N-methyl pyrrolidone; urea and possibly its alkyl C1-C4 derivatives (which are useful for solubilizing proteins), such as methyl urea; and mixtures thereof. [0050] Preferably the solvent is present in an amount of about 5 to 25% w/w of the film forming composition, more preferably about 10-15%w/w of the film forming composition. The Detergent Composition [0051] Because of the extremely low free energy of the films once applied to a surface (they typically exhibit an air/water surface tension of less than 23 dyne/cm) it is necessary to provide a cleaning composition that will allow the wetting of the initial film. Present generation hospital detergents generally have an air/water surface tension of greater than 26 dyne/cm, typically about 27 to 36 dyne/cm, and are therefore unable to effectively wet and thereby clean soil and microbes built up on the film from the hospital surfaces, [0052] In one embodiment of the invention, the film on the surface is cleaned off with a detergent composition. The detergent composition includes at least one second surfactant which lowers the air/water surface tension to less than about 24 dyne/cm, which facilitates wetting of the film by the detergent composition. [0053] The at least one second surfactant possesses an air/water surface tension of less than about 24 dynes/cm, and preferably has a critical micelle concentration (CMC), will be water soluble, compatible with the other surfactants and biocides used in the film forming composition, and be environmentally acceptable and safe to use. Several classes of surfactant fulfil these requirements, including dimeric surfactants (such as the commercial Gemini group which includes Gemini siloxane surfactants), fluorosurfactants included in the DuPont Inc. range of Capstone Surfactants, a fluorosurfactant range produced by the 3M Company, Novec FC 4430, as well as other surfactants produced in Europe and Asia. Several alkyl sulfosuccinates are excluded on compatibility with other ingredients, particularly where surfactants and WO 2015/006801 PCT/AU2014/000718 12 biocides are essentially cationic in nature. For the process of the present invention, a Gemini (dimeric) surfactant is particularly preferred as the second surfactant. [0054] The detergent composition may be made up including at least one second surfactant, or, alternatively, at least one second surfactant may be added to a pre made detergent composition. [0055] The second surfactant is preferably present in an amount of about 0.01 to 5% w/w of the detergent composition. More preferably, the second surfactant is present in an amount of about 0.05 to 2% wiw of the detergent composition. [0056] The detergent composition preferably comprises an organic chelating agent, typically derived from ethylene diamine or another amine of similar configuration. Most preferably the organic chelating agent is tetrasodium ethylene diamine tetraacetic acid. Generally, the organic chelating agent is present in an amount of less than about 1.5% w/w of the detergent composition. [0057] The detergent composition may comprise a biocide. Preferably, the biocide is a hydrophobic biocide. More preferably the biocide is selected from the group consisting of a phenolic biocide, a nitrogen containing biocide, and mixtures thereof. The Maintainer Composition [0058] In another embodiment of the invention, a maintainer composition is applied at regular intervals to the film on the surface, to clean off infectious material which has built up on the film on the surface, and to replenish areas of the film which may have become worn since the original application of the film forming composition. After several applications of the maintainer solution at, preferably, regular intervals, the surface is cleaned thoroughly with the detergent composition to remove film (and attached biofilm, if present) off the surface. The process is then repeated, that is, the film forming composition is re-applied, and the film on the surface is cleaned at regular intervals with the detergent composition and the maintainer composition is applied to the surface, also at regular intervals, but less frequently; after some time the remaining film is cleaned off using the detergent composition.
WO 2015/006801 PCT/AU2014/000718 13 [0059] An advantage of this alternative embodiment is that it avoids the need to regularly carry out the more intensive process of re-applying the film forming composition, thus saving time and money, and allowing cleaning personnel to attend to other cleaning duties. [0060] The maintainer composition comprises a small amount of the film-forming composition used in the process of the invention together with at least one surfactant which also yields in aqueous solution an air/water surface tension of less than about 24 dyne/cm. The surfactant used in the maintainer composition is preferably selected from the same group of surfactants as used in the detergent composition. [0061] The surfactant is preferably present in an amount of about 0.01 to 5% w/w of the maintainer composition. More preferably, the surfactant is present in an amount of about 0.05 to 2% w/w of the maintainer composition. [0062] Preferably the maintainer composition comprises about 2-5% w/w of the film forming composition. More preferably the maintainer composition comprises about 2-3%w/w of the film forming composition. [0063] Preferably the maintainer composition comprises at least one biocide selected from the same group of biocides as used in the film-forming composition. That is, the biocide used in the maintainer composition may be selected from the group consisting of a phenolic biocide, organic divalent metal compound, silane biocide, chemicals described as 'repellents', preferably an insect repellent, and mixtures thereof. Most preferably the biocide is a repellent selected from the group consisting of naphthalene, paradichlorbenzene, camphor, dialkyl(C1 -5) esters of phthalic acid, pyrethrum, diethyl toluamide(DEET), n-octyl bicycloheptene dicarboxamide, di-n-propyl isochinchomeronate, imiprothrin, deltamethrin, TM permethrin, bioresmethrin, bifenthrin, Bioallethrin , and terpenes. Preferably the biocide is present in the range of about 5 to 15% w/w of the maintainer composition. [0064] Preferably the maintainer composition also comprises an organic chelating agent, of the same type used in the detergent composition. Generally, the organic chelating agent is present in an amount of less than about 1 .5% w/w of the maintainer composition.
WO 2015/006801 PCT/AU2014/000718 14 [0065] The maintainer composition and detergent composition used in the same cleaning cycle may have the same or different basic formulations. That is, the same or different surfactant, biocide and/or organic chelating agent, and other components may be used in the detergent composition and maintainer composition. Preferably, the detergent composition will have the same basic formulation as the maintainer composition used in the same cleaning cycle. [0066] Generally, once the film forming composition of the invention is applied to a surface, it will last for several weeks under normal use conditions, although sections of the film may require replenishment due to high traffic on the surface. Therefore, by applying the maintainer composition at regular intervals, infectious material which has accumulated on the film may be removed, and, at the same time, the film will be replenished. [0067] An example of a routine which may be adopted to control build-up of infectious material and biofilm on a surface, using this embodiment of the process of the invention, is: Step 1: Thoroughly clean all surfaces to be treated Step 2: Apply the film forming composition to the cleaned surfaces, forming a film on the surfaces. Step 3: Daily - clean the surfaces with the detergent composition. Step 4: Weekly - clean the surfaces with the maintainer composition. Step 5: Monthly - clean the surfaces with the detergent composition, removing remaining film from the surface, and then reapplying the film forming composition. Repeat the cycle. Applications of the invention [0068] Whilst the process of the invention is ideally suited to use in a health-care facility, including a hospital or veterinary practice, where prevention of biofilm build-up is of extreme importance, clearly it is applicable to any other environment where it WO 2015/006801 PCT/AU2014/000718 15 would be desirable to prevent the build-up of infectious material on a surface. For example, the process of the invention could be used in shopping centre restrooms, in an industrial setting, such as in a food production facility, in the home, in particular kitchens, bathrooms and toilets, and in schools and child care centres, where infections such as colds and influenza are often present, particularly in winter. [0069] The film forming composition, detergent composition and/or maintainer composition each may be formulated into a liquid, spray and/or aerosol, or provided in any presentation suited to the environment in which the process of the invention is to be used. For example, the film forming composition, detergent composition and/or maintainer composition may be contained in a dissolvable packaging, incorporated into a fabric wipe, packaged in an aerosol, spray device, and /or cleaning tool, for example the cleaning tool of Australian Patent Application number 2014202266. The components may be provided separately, or together, in a kit form. [0070] The process and product of the invention may be used to provide on-going protection against build-up of infectious material on a surface. Thus biofilm build-up on surfaces may be controlled. Example 1 [0071] The formulations detailed in Tables 1 and 1A, Tables 2 and 2A are for a concentrated film forming composition used in the process of the invention, designed for packaging into aerosol, as a spray, or for incorporation into fabric wipes, such as are currently in use in hospital hygiene. Table I Silicone oil (polydinethylsi loxane) 82.2% w/w EnviroGein ADO IIm (Air Products Inc.) 0.8% w w 3-(trimethoxysilyl)propyldimethyl octadecyl ammonium chloride 0.5% w/w Phenoxv ethanol 16.5% w/w WO 2015/006801 PCT/AU2014/000718 16 In an alternative embodiment, a repellent may be added to the composition, as exemplified in Table 1A below: Table 1A Silicone oil (polydimethylsiloxane) 77.7% w/w EnviroGem ADOI Tll (Air Products Inc.) 0.8%o WYW 3 (trimethoxysilyI)propyldimethyl octadecyl amonium chloride 0,5% w/w Phenoxy ethanol 16.5 %N w/w Dimethyl phthalate 4 5% /w [0072] The formulations of Tables 1 and 1A may be further diluted by the addition of cyclohexanol, or similar solvent, for application to surfaces. [0073] Table 2 shows a suitable alternative formulation for the film forming composition, in concentrated form. Table 2 Silicone oil 799% w/w Pluronic 31 -R ITM 2.2% w/w Zinc pyrrithione 1 5 % w/w Methoxy-2-propanoi acetate 16.4%,4 w/w In an alternative embodiment, a repellent may be added to the formulation of Table 2, as exemplified in Table 2A below: Table 2A Silicone oil 77.4% w/w P ironic 31 -R. FTM 2 2% wxw Zinc pyrrithione 1 5% w/w Methoxy-2-propano acetate 64% w/w Pyrethrum 2.5% w/w [0074] The formulations of Tables 2 and 2A may be diluted with dimethylpropylene glycol, as required, for application to a surface. [0075] To evaluate the effectiveness of the film in prevention of biofilm formation on a surface, coupons of a test surface, to which has been applied the film forming WO 2015/006801 PCT/AU2014/000718 17 composition of Table 1, 1A, 2 or 2A, are immersed in a liquid culture of test microbes, withdrawn, and the coupons are allowed to air dry for 24 hours. The coupons are then examined by scanning electron microscopy for the presence of biofilm. Example 2 [0076] A typical detergent composition used in the process of the invention, and meeting the requirements of a hospital grade detergent, has the formulation given in Table 3: Table 3 Alkyi (C -12-16.) dimiethvlben-zylan-mion-iumi chloride 12,0% wv/w Alkyl (C12-14) trimethylethylbenzylammonium chloride 12 0% w/w Alkyl (C9-1 1) poly (7-10) ethoxylate I1 5 % w/w Tetrasodium ethylene diamine tetraacetate 1 25% wv w Sodium bromide 0 05% wlw Gemini surfactant Tego TwinTM 1 /5% w/w Isopropanol 6.5%x/w Diethylenglycol monoethylether 8 0% ww Water balance Ph 6.5-8.5 [0077] This formulation may be diluted for use with water, ethanol or isopropanol, or mixtures thereof, in an amount of 1 part concentrate with 50 to 100 parts of diluent. [0078] To inhibit build-up of infectious material on a surface, the film forming composition of Table 1, 1A, 2 or 2A is applied to a surface which has been cleaned using standard hospital cleaning procedures. Subsequently, the detergent composition of Table 3 is used to clean the surface. This process is repeated routinely. Example 3 [0079] Table 4 is an example of a maintainer composition used in the process of the invention.
WO 2015/006801 PCT/AU2014/000718 18 Table 4 Ortho phenylphenol 7.8% w/w Amylphenol 7.7% w/w Sodium lauryl sulphate 1,0.6% w/w Tetrasodium ethylene diamine tetraacetate 1.2 5% w/ I sopropanol 24.5% w/w Gemini surfactant Tego TwinThl 0.85% w/w Film fomiing composition of Table 1, 1 A, 2 2.7 5 %w/w or 2A Water balance Example 4 [0080] An example of an embodiment of the process of the invention is as follows: [0081] After the application of the film forming composition of Tables 1, 1A, 2 or 2A to a surface, the surface is cleaned at regular intervals (typically daily) with the detergent composition of Table 3. At weekly intervals, the maintainer composition of Table 4 is applied to the surface. After several applications of the maintainer composition, the surface is thoroughly cleaned using the detergent composition of Table 3, removing remaining film from the surface and biofilm that might have built up. The process is then repeated: the film forming composition of Tables 1, 1A, 2 or 2A is re-applied to the surface, followed by cleaning using the detergent composition and application of the maintainer composition,