ANTI-MICROBIAL COMPOSITION
This invention relates to anti-microbial compositions and to formulations including the antimicrobial compositions.
Microorganisms are known to present health hazards due to infection or contamination. They can also cause spoilage of items such as clothing and unpleasant odours. When microorganisms are present on the surface of a substrate they can replicate rapidly to form colonies.
Many anti-microbial agents that can destroy microorganisms that 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.
The known anti-microbial agents and the compositions that contain these anti-microbial agents destroy microorganisms by a number of different mechanisms.
For example, many anti-microbial agents are poisonous to microorganisms and, therefore, destroy microorganisms with which they are contacted. Examples of this type of antimicrobial agent include hypochlorites (bleaches), phenol and compounds thereof, and salts of copper, tin and arsenic. However, some of these agents can be highly toxic to humans and animals as well as to microorganisms. Consequently these anti-microbial agents are dangerous to handle, and specialist handling, treatment and equipment are therefore required in order to handle them safely. The manufacture and disposal of compositions comprising this type of anti-microbial agent can, therefore, be problematic. There can also be problems associated with the use of compositions containing this type of anti-microbial agent, particularly in consumer materials where it is difficult to ensure that they are used for designated purposes.
Herein, unless the context indicates otherwise, "toxicity" is intended to refer to toxicity to complex organisms such as mammals. References to "toxic" are to be construed accordingly.
Once the anti-microbial agents enter the environment they can affect the health of life forms that they were not intended to affect. Furthermore, the anti-microbial agents are often highly
stable and can cause environmental problems for long periods of time.
Other anti-microbial agents currently in use include antibiotic type compounds. Antibiotics disrupt the biochemistry within microorganisms. Although antibiotics are effective, it is believed that they may selectively permit the development of resistant strains of the species that they are used against.
Another method of microbial control is the use of oxidising agents in materials, such as household bleach, which can be based on hypochlorite or peroxides such as hydrogen peroxide. These materials are effective in a wet environment for sterilization and cleansing but stop working shortly after drying.
The listing or discussion of an apparently prior-published document in this specification should not necessarily be taken as an acknowledgment that the document is part of the state of the art or is common general knowledge.
There is a need to provide compositions for a variety of applications and uses, such as cleaning applications that have anti-microbial properties and that address one or more of the problems set out above. However, it is not a straight forward matter to do this. There are regulations such as the Biocidal Products Regulations (Directive 98/8/EC) which regulates the use of anti-microbial agents both in terms of the nature and the amount of a given antimicrobial agent that may be used. Additionally, the potential reactivity of an anti-microbial agent once in a composition is important as some anti-microbial agents are rendered inactive by chemical reaction. Even where an anti-microbial agent is not deactivated by chemical reaction it may have its activity suppressed by other components of the composition.
The present inventors have surprisingly found that the foregoing deficiencies can be overcome by certain combinations of components. It has also been found that compositions containing these combinations of components can have some surprising and unexpected properties.
In particular, the present invention provides anti-microbial compositions suitable for a variety of consumer applications. The compositions of the invention are particularly suitable for use on hard surfaces. Some compositions of the invention are suitable for cleaning a hard surface and also provide a residual anti-microbial effect.
The compositions of the invention can be used for a range of applications and are particularly suitable for use on hard surfaces. The compositions of the invention may be used on hard surfaces indoors such as those found in a domestic setting, an office or a public building such as a hospital or out of doors.
As used herein, by the term cleaning we mean the removal of soils, such as dirt, soap scum and limescale.
The compositions of the invention comprise (i) an anti-microbial component comprising at least one quaternary ammonium compound; (ii) a polymer as defined below; (iii) a polar solvent; (iv) at least one non-ionic surfactant and (v) a chelate. The anti-microbial component (i) preferably contains at least two quaternary ammonium compounds.
While it is envisaged that compositions of the invention can contain additional ingredients as described below and other ingredients that are standard in the art, the compositions of the invention may consist of or consist essentially of the components listed in the paragraph above.
For the avoidance of doubt, in this specification when we use the term "comprising" or "comprises" we mean that the composition or formulation or component being described must contain the listed ingredient(s) but may optionally contain additional ingredients. When we use the term "consisting essentially of or "consists essentially of we mean that the composition or formulation or component being described must contain the listed ingredient(s) and may also contain small (for example up to 5% by weight, or up to 1% or 0.1% by weight) of other ingredients provided that any additional ingredients do not affect the essential properties of the composition, formulation or component. When we use the term "consisting of we mean that the composition or formulation or component being described must contain the listed ingredient(s) only. These terms can be applied in an analogous manner to processes, methods and uses.
By "substantially free" we mean that the composition or formulation or component being described contains less than 3% by weight, preferably less than 1%, more preferably 0.1% or less by weight of the stated ingredient. For example, the compositions of the invention that are substantially free of alcohol contain less than 3% by weight of alcohol, preferably less than 1% by weight of alcohol, more preferably 0.1% or less alcohol.
By the term "anti-microbial" we mean 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 antimicrobial 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.
The compositions of the invention 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 that inhibit the growth of the respective microorganisms but do not necessarily kill the microorganisms and agents that kill the respective microorganisms. Thus, for example, within the term anti-bacterial we include agents that inhibit the growth of bacteria but may not necessarily kill bacteria and bactericidal agents that 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 of the invention 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 of the invention are effective against a wide range of organisms, including Gram negative and Gram positive bacteria, funguses, yeasts, viruses and some spore formers.
The anti-microbial component (i) may comprise (a) at least one, preferably at least two quaternary ammonium compounds having anti-microbial properties and optionally (b) one or more additional anti-microbial agents. Commercially available blends of quaternary ammonium compounds having anti-microbial properties may be used.
The quaternary ammonium anti-microbial agent(s) used in the present invention are typically water soluble at room temperature and pressure.
Suitable anti-microbial quaternary ammonium compounds include compounds of formula (A)
wherein R and R2 are each independently a straight chain, unsubstituted and uninterrupted Ce-12 alkyl group and X" is a halide anion such as chloride, bromide, fluoride, iodide or sulphonate, saccharinate, carbonate or bicarbonate and benzalkonium compounds having the formula (B)
wherein m is from 8 to 18, and X" is a halide anion such as chloride, bromide, fluoride, iodide, sulphonate, saccharinate, carbonate or bicarbonate. The compounds of formula (B) are generally called benzalkonium compounds. The benzalkonium chloride is provided and/or used as a mixture of C8.i8 alkyl groups, particularly a mixture of straight chain, unsusbtituted and uninterrupted alkyl groups n-C8H17 to n-C18H37, mainly n-C 2H25 (dodecyl), n-C14H29 (tetradecyl), and n-C16H33 (hexadecyl). Preferably m is 8, 10, 12, 14 and/or 16. Most preferably m is from 12 to 16, for example 12, 14 and/or 16.
In the compounds of formula (A) each group R1 and R2 is independently a straight chain, unsubstituted, uninterrupted C8-12 alkyl group, for example an alkyl group containing 8, 9, 10, 11 or 12 carbon atoms. In one aspect, the groups R1 and R2 contain the same number of carbon atoms but this is not essential and compounds in which R1 and R2 contain different numbers of carbon atoms can be used.
The anion of each quaternary ammonium compound in the compositions of the invention may be the same or different. For example, the anion of a compound of formula (A) may be
the same or different to the anion of a compound of formula (B). In one aspect, the anion for each compound is chloride.
Examples of quaternary ammonium compounds of formula (A) include di-n-decyldimethyl ammonium chloride, octyl decyl dimethyl ammonium chloride and dioctyl dimethyl ammonium chloride.
Examples of commercially available compounds of formula (A) include Acticide DDQ 50, Bardac 2250, 2280 and Maquat 4480E, from Mason Chemical Company, USA.
Examples of quaternary ammonium compounds of formula (B) include N,N- benzyldimethyloctylammonium chloride, Ν,Ν-benzyldimethyldecylammonium chloride , N- dodecyl-N-benzyl-N,N-dimethylammonium chloride, N-tetradecyl-N-benzyl-N,N- dimethylammonium chloride, N-hexadecyl-N,N-dimethyl-N-benzylammonium chloride, N,N- dimethyl N-benzyl N-octadecyl ammonium chloride and mixtures thereof.
Commercially available benzalkonium chloride often contains a mixture of compounds with different alkyl chain lengths. Examples of commercially available benzalkonium chlorides that may be used in the present invention are shown in the following Table. It will be appreciated that other commercially available benzalkonium compounds may alternatively or additionally be used.
CAS Number Chemical Name
For example, Acticide Bac 50 - Quaternary ammonium compounds,
63449-41-2 benzyl C8-18 alkyl dimethyl chlorides (25-50%), from Thor Chemicals in
UK, or BQ 451-8 from Albermarle, Global).
Alkyl (95% C14, 3% C12, 2% C16) dimethyl benzyl ammonium chloride,
68424-85-1 for example Barquat MB50/80, both registered as blends using the same
CAS number, from Lonza Inc, Switzerland
Alkyl (95% C14, 3% C12, 2% C16) dimethyl benzyl ammonium chloride dehydrate
Alkyl (95% C14, 3% C12, 2% C16) dimethyl benzyl ammonium chloride monohydrate
Alkyl (C14, C12, C16) dimethyl benzyl ammonium chloride
Alkyl dimethyl cumenyl ammonium chloride
Alkyl dimethyl isopropyl benzyl ammonium chloride
Alkyl(68% C12, 32% C14)dimethyl dimethylbenzyl ammonium chloride
Alkyl* dimethyl benzyl ammonium chloride *(50% C12, 30% C14, 17%
8001-54-5 C16, 3% C18), for example NOBAC® BZK, from Mason Chemical
Company, USA
It will be appreciated that a single CAS number often refers to more than one blend or mixture. A CAS classification for a commercial preparation typically covers blends comprising specified compounds in amounts within defined ranges. The compositions having the CAS numbers quoted above are only examples of compositions having a given CAS number that may be used in the present invention.
The amount of component (i) in the compositions of in the present invention will vary depending on a number of factors, such as the intended use of composition and the particular compound(s) used as component (i).
If a mixture of quaternary ammonium compounds of formula A and formula B are used the weight ratio of A to B is not limited and may be from about 1 :10 to about 10:1 , preferably from 1 :5 to 5:1 or from about 1 :4 to about 4:1 , such as about 2:1 or from about 3:2 to about 2:3.
An example of the quaternary ammonium component is a mixture comprising octyl decyl dimethyl ammonium chloride and/or didecyl dimethyl ammonium chloride and/or dioctyl dimethyl ammonium chloride, and alkyl (C14, 50%; C12, 40%, C16, 10%) dimethyl benzyl ammonium chloride. These compounds may be used together in any suitable ratio. One such ratio is about 2:1 :1:2.7 by weight. A suitable mixture is sold commercially as Maquat MQ 615M by Mason Chemical.
Component (i) may consist essentially of or consist of at least one or at least two compounds of formula (A) or may consist essentially of or consist of at least one or at least two compounds of formula (B).
In one aspect, component (i) comprises, consists essentially of or consists of at least one compound of formula (A) and at least one compound of formula (B). In this aspect the ratio by weight of the compound of formula (A) to the compound of formula (B) is for example from 10:1 to 1 :10 or 4:1 to 1 :4, such as 3:2 or 2:3.
In one aspect, the quaternary ammonium antimicrobial component (i) may consist of (1) a component consisting essentially of a single compound of formula (A); and
(2) a component consisting essentially of at least one benzalkonium compound having the formula (B), wherein the ratio by weight of (1) to (2) is from 10:1 to 1:10 or 4:1 to 1:4, such as 3:2 or 2:3. The quaternary ammonium compounds used in the present invention are typically not polymerized.
The compositions of the invention must contain at least one, such as at least two, quaternary ammonium anti-microbial agents. They may additionally comprise any other suitable anti- microbial agent(s) (b), such as those described in the EPA (United States Environmental Protection Agency) Listing and Annex I and Annex 3 of the EC Biocides Directive.
Suitable anti-microbial agents (b) include anti-microbial agents that are not quaternary ammonium compounds. Preferably, these additional antimicrobial agent(s) are water soluble at room temperature and pressure.
Examples of suitable additional antimicrobial agents include but are not limited to polymeric biguanidines (e.g. polyhexamethylene biguanidine (PHMB)), non-polymeric biguanides (e.g. chlorhexidine), silver, octenidine HCI, amphoteric compounds, iodophores, phenolic compounds, amine anti-microbial agents and nitrogen based heterocyclic compounds, ortho phenyl phenol (OPP), and nitro bromopropanes (e.g. bronopol (INN), 2-bromo-2- nitropropane-1 ,3-diol), naturally derived biocidal compounds (e.g. honey and extracts of honey such as those comprising methyl glyoxal, flavenoids based antimicrobials, essential oils and organic acids e.g. lactic acid or citric acid).
In one aspect, the compositions of the invention are free of inorganic antimicrobial agents such as those comprising silver. In this aspect, the additional antimicrobial agent is an organic antimicrobial agent. Preferred additional antimicrobial agents (b) include polymeric biguanidines. One preferred additional antimicrobial agent (b) is polyhexamethylene biguanidine (PHMB). PHMB is commercially available from Arch Biocides as Vantocil (Industrial grade quality or Cosmocil (Cosmetic grade quality, For example PHMB20 supplied by Thor). An example of amine anti-microbial agents that may be used in the compositions of the invention is a compound of formula (C)
^ (CH2)3- NH2
R - N
(CH2)3- NH2
where R is an unsubstituted C8 to C18 alkyl group. Preferably R is from 10 to 14, for example 12. A preferred compound of formula (C) is dodecyl dipropylene triamine (N,N-bis(3- aminopropyl)-dodecylamine CAS no. 2372-82-9), commercially available from Lonzabac as Lonzabac 12, it is also known as Triameen YD12 (available from Akzo Nobel).
In one aspect, the compositions of the invention do not comprise PHMB or they may be free of polymeric biguanides or they may be free of non-polymeric biguanidines or free of biguanidines (eg free of polymeric and non-polymeric biguanides). In one aspect of the invention the anti-microbial composition does not comprise any isothiazalones and/or any nitrobromopropanes such as bronopol and/or any hypochlorites.
In one particular aspect, compositions of the invention that comprise a compound of formula (C), for example N,N-bis(3-aminopropyl)-dodecylamine do not comprise PHMB or are free of polymeric biguanidines or free of biguanidines (e.g. free of polymeric and non-polymer biguanidines). However, compositions that comprise a compound of formula (C), for example N,N-bis(3-aminopropyl)-dodecylamine and a biguanidine, such as a polymeric or non-polymer biguanidines, for example PHMB are also envisaged. An example of a composition of the invention is a composition in which component (i) is (a) at least one or at least two quaternary ammonium compounds as described above, for example a compound of formula (A) and/or a compound of formula (B) and (b) at least one polymeric biguanide such as PHMB, which may be the only additional anti-microbial component (b) or the component (b) may contain a further anti-microbial ingredient.
An example of a composition of the invention is a composition in which component (i) comprises (a) at least one or at least two quaternary ammonium compounds as described above, for example a compound of formula (A) and/or a compound of formula (B) and (b) at least one compound of formula (C), such as N,N-bis(3-aminopropyl)-dodecylamine.
An example of a composition of the invention is a composition in which component (i) comprises (a) at least one or at least two quaternary ammonium compounds as described above, for example a compound of formula (A) and/or a compound of formula (B) but does not comprise an additional antimicrobial agent (b).
In one aspect, component (b) does not comprise isothiazole. In this aspect, the compositions of the invention are free of isothiazole. The compositions of the invention can be provided in concentrated form for dilution before use or in ready to use form. It is preferred that the compositions of the invention are provided in ready to use form and, unless otherwise stated, information about amounts (such as weight% or ppm) provided in this document relate to ready to use compositions. Typically, but not essentially, the compositions of the invention have a concentration of component (i) of from about 100 or 500 to about 20000 ppm, such as from about 2000 to about 10000 ppm, or 3000 to 8000 ppm.
The polymers suitable for use in the present invention are hydrophilic polymers comprising at least two of the following types of monomer:
(1) a monomer having a permanent cationic charge or a monomer that is capable of forming a cationic charge upon protonation;
(2) an acidic monomer having an anionic charge or capable of forming an anionic charge; and
(3) a neutral monomer.
Any combination of these types of monomer may be used. For example, suitable polymers include but are not limited to those comprising, consisting of or consisting essentially of at least one monomer of type (1) and at least one monomer of type (2) and polymers comprising, consisting of or consisting essentially of at least one monomer of type (1) and at least one momoner of type (3), polymers comprising, consisting of or consisting essentially of polymers comprising at least one monomer of type (2) and at least one monomer of type (3) and polymers comprising, consisting of or consisting essentially of at least one of each of the three types of monomer.
The polymers used in the present invention may have a polyampholyte structure such that the charge and surface adsorption are determined by pH. For example, the polymer may be an acrylic acid amine-functional polymer. Examples of suitable hydrophilic polymers are described in US6,569,261, US6.593.288, US6.703.358 and US6.767.410, the disclosure of these documents is incorporated herein by reference. These documents describe water- soluble or water-dispersible copolymers including, in the form of polymerized units, (1) at
least one amine-functional monomer, (2) at least one hydrophilic monomer with an acidic nature and (3) optionally at least one neutral hydrophilic monomer having an ethylenic unsaturation. The copolymers include quaternized ammonium acrylamide acid copolymers. Examples of a cationic monomer (1) include but are not limited to:
![Figure imgf000012_0001](https://patentimages.storage.googleapis.com/47/8b/bb/56fb83e4ee17df/imgf000012_0001.png)
Diallyldimethylammonium halides such as diallyldimethylammonium chloride (DADMAC) or the corresponding bromide. Alternatively, the counter ion may be sulphate or phosphate. Similar momomer units, such as those in which one or more of the CH
3 groups is replaced by a C
2 to 12 for example a C
2 t
0 6 alkyl group or one or more of the CH
2 groups is replaced by an alkyl group having from 2 to 12, for example from 2 to 6 carbon atoms may be used. In other words, other similar commercially available monomers or polymers containing such monomers may be used.
N,N,N-trimethyl-3-((2-methyl-1-oxo-2-propenyl)amino)-1- propanaminium halides, such as the chloride (MAPTAC, also known as methacryl- amido(propyl)-trimethyl ammonium chloride).
Examples of the acidic monomer (2) include but are not limited to acrylic acid and methylacrylic acid. Examples of neutral monomers (3) include but are not limited to:
2-(Dimethylamino)ethyl methacrylate (DMAEMA),
N-vinyl pyrrolidone (NVP),
N-vinylimidazole,
methacrylamide. An example of a polymer suitable for use in the present invention is a polymer comprising, consisting of or consisting essentially of DMAEMA, MAPTAC and methylacrylic acid.
Suitable polymers include those sold under the trade name Mirapol, for example as Mirapol Surf-SHO, Mirapol Surf-S200 or Mirapol Surf-S500 available from Rhodia, Novecare.
Other suitable polymers include polymers comprising, consisting of or consisting essentially of DADMAC and acrylamide, such as those sold under the trade name Polyquat 7 or PQ7 from Surfacare or under the trade name Merquat S from Lubrizol. Other suitable polymers include polymers comprising, consisting of or consisting essentially of DADMAC and methacrylamide and/or, acrylic acid or methacrylic acid.
Polymers comprising, consisting of or consisting essentially of MAPTAC and acrylamide or methacrylamide are also suitable for use in this invention. Also suitable are polymers comprising, consisting of or consisting essentially of MAPTAC and vinyl pyrrolidone, such as Polyquat 28. Suitable polymers include those sold under the trade names Polyquart Pro. (which is polyquat 28 plus silicone) and Polyquart Ampo 140 from BASF.
Other suitable polymers include polymers comprising, consisting of or consisting essentially of MAPTAC and acrylic acid or methacrylic acid, such as those sold under the trade name Polyquat Ampho, eg Polyquat Ampho 149.
Polymers comprising, consisting of or consisting essentially of DMAEMA and vinylpyrrolidone are suitable for use in this invention. An example of such a polymer is sold under the name PQ11 by BRB International.
Other suitable polymers include polymers comprising, consisting of or consisting essentially of DMAEMA and acrylamide, such as the polymer sold under the trade name Polyquat 5. Typically the polymers used in the present invention are unmodified. By this we mean that the polymers are, for example, not modified by reactions such as grafting with a functionalizing agent or a hydrophobic agent.
The ratio in terms of parts per million (PPM) of the quaternary ammonium component (a) to the polymer (ii) is typically from 200:1 to 1:20, such as from 1:1 to 20:1 or 10:1, for example about 2:1 or about 4:1. In a particular aspect the amount in ppm of component (a) is greater than or equal to the amount of polymer. For example, the ratio of component (a) to the polymer (ii) may be about 5:1 or about 4:1 or about 3:1 or about 2:1 or about 1:1. As an example, compositions of the invention may comprise from 500 to 3000 ppm of polymer, such as from 1000 to 2500 ppm or about 2000 ppm.
The compositions of the invention may comprise a single polymer (that is only one combination of monomer units) or two or more polymers may be used (that is polymers made up of two or more combinations of monomer units).
The pH of the compositions of the invention can vary within wide limits. Typically, the pH of a composition of the invention will be similar to that of known compositions which are intended to be used for the same purpose or a similar purpose to a given composition of the invention. Formulations for use for purposes such as kitchen or bathroom cleaning may have either a low pH, such as a pH of 3 or below, for example about 2, or a high pH such as a pH of 10 or above, for example 11.
In one aspect, the compositions of the invention have a pH of 2.5 or more, for example 3.5 or more or 4 or more or pH 4.5 or more, such as from 5 to 13, for example from about pH 5 to about pH 12, such as from about pH 5 to a pH of 9 or above.
The compositions of the invention comprise at least one suitable non-ionic surfactant or a combination of surfactants including at least one non-ionic surfactant, for example at least one non-ionic surfactant optionally in combination with at least one cationic and/or amphoteric surfactant. The selection of surfactants will depend on the nature of and the
intended purpose of the composition. Suitable surfactants for use in formulations intended for different purposes will be within the knowledge of the person of ordinary skill in the art. Likewise, the selection of suitable amounts of surfactant will be within the knowledge of the person of ordinary skill in the art.
Some compositions of the invention comprise an amphoteric 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 surfactant. The amphoteric surfactant and the non-ionic surfactant may, for example, be used in approximately equal amounts by weight.
In one aspect, the composition is substantially free of or free of anionic surfactant. In another aspect, the compositions of the invention do not comprise an amphoteric surfactant.
The compositions of the invention comprise a polar solvent, component (iii). Suitable polar solvents include, but are not limited to, water, alcohols, glycol ethers and mixtures thereof.
Suitable alcohols include, but are not limited to, straight or branched chain Cn 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. Preferred polar solvents for use in the compositions of the invention include, but are not limited to, water, ethanol, n-propanol, isopropanol, ethylene glycol ethers, propylene glycol ethers, butyl diglycol (BDG) and dipropylene glycol methyl ether (Trade name Dowanol DPM) and mixtures thereof. In one aspect, the composition comprises water or a mixture of water and one or more alcohols selected from the alcohols described above. In such mixtures, water is preferably the major component. The polar solvent may consist essentially of water or consist of water.
If the compositions of the invention comprise an alcohol, the alcohol is typically present in an amount lower than the amount necessary for the alcohol to provide an antimicrobial effect.
In one aspect, the compositions of the invention are substantially free of alcohol.
example, the compositions may contain 1% or less by weight alcohol. For example, the compositions may contain less than 1% or less than 0.5% by weight or 0.1% by weight or less of an alcohol such as isopropanol. As an example, compositions of the invention may comprise no isopropanol or may comprise no alcohol.
The composition may comprise water or a mixture of water and one or more alcohols selected from the alcohols described above. In such mixtures, water is preferably the major component. Suitable non-ionic surfactants include, but are not limited to, amine oxides, alkyl polyglucosides, linear and branched 1° and 2° alcohol ethoxylates, nonyl phenol ethoxylates, and ethoxylated/propoxylated (EOPO) block polymers.
Amine oxides suitable for use in the present invention are those with an alkyl chain length of C8-C16. Amine oxides are suitable for use in the present invention because they can provide better cleaning properties and can have less of a degradative effect on surfaces in particular plastic than some other surfactants.
Examples of suitable amine oxides compounds include, but are not limited to, C8 amine oxide surfactants such as those sold under the trade name Macat AO-8 (Mason Chemical Company), C10 amine oxides such as those sold under the trade names Euroxide D40 (EOC Group) and Mackamine C10 (Rhodia Novecare), Longer chain glucosides such as C 2 amine oxides for example those sold under the trade names Euroxide LO/A (EOC Group), Ammonyx LO (Stepan Chemicals) and Surfac AO30 (Surfachem) and C10-C16 amine oxides such as those sold under the trade name Ammonyx C (Stepan Chemicals).
Alcohol alkoxylates suitable for use in the present invention include primary and secondary linear and branched alcohol ethoxylates, such as C6-C18 alcohol ethoxylates having 2 to 20 EO units such as 7 to 12 EO units. Preferred primary linear alcohol alkoxylates include Cg. n alcohol ethoxylates having 5 to 12 EO units such as 7 to 12 EO units. These surfactants are available under the commercial name of the Neodol series (From Shell Chemical Company). Examples of secondary C 12-15 alcohol ethoxylates, include those that have from about 3 to about 10 EO units, such those available in the Tergitol series (Dow), particularly those in the Tergitol 15-S series. Examples of suitable branched alcohol exthoxylates include C10 Guerbet alcohol with 3 to 14 EO units such as Lutensol XL and XP series (available from BASF). Alcohol ethoxylates having EO and PO mixtures are also suitable, these include
linear and branched alcohol ethoxylates with PO-EO units such as ECOSURF™ EH Surfactants (DOW) and Plurafac D250 (BASF). Alkylphenol ethoxylate (APE) surfactants may also be used. A further class of non-ionic surfactants that may be used is alkoxy block copolymers, in particular, compounds based on ethoxy/propoxyl block copolymers. Polymeric alkylene oxide block copolymers include non-ionic surfactants in which the major portion is made up of block polymeric C2-4 alkylene oxides. Specific examples include surfactants commercially available under the Pluronic trade name and in particular the Pluronic F series, Pluronic L series, Pluronic P series and Pluronic R series.
A further class of suitable non-ionic surfactants are alkyl polyglucosides or glucosides. Suitable examples include Surface APG a capryl glucoside available from Surfachem and the Glucopon seriers available from BASF (Glucopon 425N/HH (C8-14), Glucopon 215 (C8- 10) and Glucopon 600 (C12-14) alkyl polyglucoside).
In one aspect of the invention, the compositions of the invention may be free of alcohol alkoxylate. For example, compositions of the invention that contain a compound of formula (C) as defined herein such as those containing N,N-bis(3-aminopropyl)-dodecylamine may be free of alcohol alkoxylate.
The compositions of the invention may alternatively or additionally be free of alkyl polyglucoside. For example, compositions of the invention that contain a compound of formula (C) as defined herein such as those containing N,N-bis(3-aminopropyl)- dodecylamine may be free of alkyl polyglucoside (APG).
Typically, the component (iv), is present in the compositions of the invention in an amount of from about 500 to 35000 ppm. The amount of surfactant (iv) depends on a number of factors such as the pH of the composition and the intended use of the composition. Typically higher pH compositions require higher concentrations of non-ionic surfactant. A preferred range for the amount of surfactant (iv) for a composition having a pH of from 8 to 10.5 is from 2000 to 13500 ppm.
Suitable amphoteric surfactants include but are not limited to C6-C20 alkylamphoacetates or amphodiacetates (such as cocoamphoacetates), C 0-C18 alkyldimethyl betaines, Ci0-C18 alkyl amidopropyldimethyl betaines. Examples include but are not limited to coconut amphoteric
surfactant cocoamidopropyi betaine (CAPB) (Surfac B4, CAS 61789-40-9), coco imidazoline betaine, oleo amido propyl betaine, and tall oil imidazoline.
Without wishing to be bound by theory, it has been found that the surfactant component can have several effects on the properties of the compositions of the invention. The presence of a non-ionic surfactant can improve the cleaning ability of the composition, that is improve the removal of soils and dirt. It has been found that the use of an alcohol alkoxylate in combination with an amine oxide can in some situations improve cleaning performance. Additionally, the inclusion of non-ionic surfactants can improve the stability of the compositions of the invention.
The present inventors have surprisingly found that by using the combinations described herein stable compositions that provide residual antimicrobial performance can be obtained. In one aspect, the compositions of the invention are free of glycol ethers, for example they are free of propylene glycol n-butyl ether and/or free of a binary solvent combination of a glycol with a linear primary alcohol.
The compositions of the invention comprise a chelate. Any suitable chelate may be used. Suitable chelates include but are not limited to EDTA (Ethylenediaminetetraacetic acid), Gluconate, GLDA (Glutamic acid diacetic acid) - Trade name Dissolvine GL, EDDS (Ethylenediamine-N.N'-disuccinic acid), DPTA (Diethylenetriaminepentaacetic acid), HEDTA (Hydroxyethylethylenediaminetriacetic acid), MGDA (Methyl glycine diacetic acid) - Trade name Trilon M, PDTA (1 ,3-propylenediaminetetraacetic acid), and EDG (Ethanoldiglycineic acid) and mixtures thereof. If the chelate contains a counter ion that counter ion is preferably metallic. Suitable metallic counter ions include but are not limited to Na, Ca, Fe, K, Zn, Mg and Mn.
Preferred chelates are GLDA (Dissolvine) and EDTA.
The chelate is typically present in an amount of from about 100 to 10,000 ppm, preferably from about 400 to 3,000 ppm, for example from about 500 to 2000ppm.
It will be appreciated that the compositions of 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. The person of ordinary skill in the art will
know which additional ingredients are suitable for use in compositions for different applications.
Additional ingredients that may be used in the compositions of the invention include but are not limited to buffering agents include, but are not limited to, hydrophobic materials such as siloxanes, bicarbonate salts such as sodium bicarbonate, sodium chloride, potassium chloride, triethylamine, triethylenetetramine tetraethylethylenediamine, tetramethylenediamine, piperazines, histadines, imidazoles, morpholines, aminoalcohols such as 2-aminoethanol and 2-amino-2-methyl-1-propanol (AMP) and triethanolamine, phosphate buffers, citrate buffers and salts thereof and mixtures thereof.
Complexing agents may be used. For example, complexing agents can be used to help provide a clear composition even when the compositions of the invention are used with hard water. Suitable complexing agents include but are not limited to sodium salts of methane diphosphonic acid, hydroxythenae-1 ,1-diphosphonic aicd, 1-aminoethane-1 ,1-diphosphonic acid, amino -trimethylene phosphonic acid, ethylene diamine-tetra (methylene phosphonic acid), diethylene triamine-penta (methylene phosphonic acid), 2-phos-phonobutane-1 ,2,4- tricarboxylic acid, and nitrilotriacetic acid (NTA), citrates and gluconates or salts of glutaric, adipic and succinic acids and mixtures thereof. pH modifiers may be used. Suitable pH modifiers include but are not limited to acids such as citric, sulfamic, hydrochloric, phosphoric, nitric, lactic, formic, acetic glycolic or gluconic acids or other mineral or organic acids or bases such as sodium or potassium hydroxide and carbonates and mixtures thereof. The compositions of the invention may alternatively or additionally contain salts such as the halides of alkali metals or alkaline earth metals such NaCI or KCI. In some situations, the use of salts can facilitate the formation of a stable composition.
Some compositions of the invention are free of or substantially free of acids or bases. For example some compositions of the invention do not comprise a citrate or citric acid or lactic acid. Other compositions may contain an acid or base as is appropriate for their intended use. In one aspect of the invention the composition contains 0.5% by weight or less of formic acid or is free of formic acid. Siloxanes suitable for use in the present invention include those having formulae (H3C)[SiO(CH3)2]nSi(CH3)3l and (H3C)[SiO(CH3)H]nSi(CH3)3, and mixtures thereof, where n is
an integer, of from 1 to 10, more preferably from 1 to 6 and most preferably from 1 to 4, for example n may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, especially 1 , 2, 3 or 4. 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). Commercially available siloxanes that may be used include those available from Xiameter under the trade names PMX 200 and PMX-1184.
In a particular aspect of the invention the compositions of the invention do not comprise or are substantially free of a hydrophobic material, for example they do not comprise or are substantially free of siloxanes, silicones, polysiloxanes such as polydimethylsiloxanes.
The compositions of the invention may also contain other ingredients that are standard in the art such as colorants, fragrances, emollients, antioxidants, thickeners and corrosion inhibitors and mixtures thereof.
Typically, component (i) is present in the compositions of the invention in an amount of from about 0.05 to about 2 % by weight of the compositions, such as from about 0.2 or about 0.5 to about 1.5 or about 1.0 %. The ratio by weight of the component (a) to the additional anti-microbial agent (b) is typically from about 1 :10 or about 1 :2 or about 1 :1 to about 50:1 , or to about 30:1 , for example, from about 1 :1 or about 2:1 or about 3:1 to about 20:1 or about 10:1 or about 6:1 or from about 0.4:1 to about 4:1 , such as about 0.55:1 to about 3.16:1 , for example about 1 :1 , or about 2:1 , or about 2.75:1 or about 3:1 or 4:1.
Typically, the polar solvent component (iii) is present in the compositions of the invention 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%).
Typically, the additional anti-microbial agent component (b) is present in the compositions in an amount of from about 0.001 to about 0% by weight of the compositions, such as from about 0.005 to about 5%, 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%).
An example of a composition of the invention is a composition comprising:
(i) (C10H2i)2(CH3)2N+Cr and a benzalkonium chloride, which may be in a ratio in terms weight from about 1 : 10 to 10: 1 , for example about 4: 1 ;
(ii) a polymer as defined above, such as a polymer comprising DMAEMA, MAPTAC and methylacrylic acid, or DADMAC and acrylamide, methacrylamide, acrylic acid or methacrylic acid, or MAPTAC and acrylamide or methacrylamide, or MAPTAC or DMAEMA and vinyl pyrrolidone, or MAPTAC and acrylic acid or methacrylic acid, or DMAEMA and acrylamide;
(iii) water;
(iv) a non-ionic surfactant such as an alcohol ethoxylate or amine oxide or a mixture thereof; and
(v) a chelate such as EDTA or GLDA.
This composition has a pH of at least 2.5, such as at least 3.5.
It is preferred that the polymer comprises DMAEMA, MAPTA and methylacrylic acid, a commercial example of which is sold under the trade name Mirapol Surf-S 110.
Without wishing to be bound by theory, the inventors have found that there are very significant advantages associated with the compositions of the invention. It has been found that in use compositions of the invention have advantageous anti-microbial effects. For example, such compositions have an anti-microbial effect when initially applied to a surface (so called "wet kill") and they can also have a residual anti-microbial effect in that they control, reduce or prevent the formation of new microbial colonies at the surface (so called "dry kill").
The compositions of the invention are also resistant to washing with water and to wiping. This means that the compositions 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.
The compositions of the invention provide a residual antimicrobial effect and provide an antimicrobial effect even after being subjected to the residual efficacy test described herein. That is, these compositions provide a reduction in micro-organisms when subjected to a three wear cycle test on a non-porous stainless steel, glass or plastics substrate and typically provide a 3 log or greater reduction over a 24 hour period. By this we mean that 24 hours after application of the composition of the invention to the surface, if micro-organisms are
applied to that surface (without the further addition of a composition of the invention or another anti-microbial agent) at least a 3 log reduction in those micro-organisms will be achieved. An advantage of the invention is that it is possible 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 invention is therefore general in its control of microorganisms.
Typically, the compositions of the invention do not need to contain materials that are highly toxic to mammals. The anti-microbial agents used in the anti-microbial compositions are typically well known and widely understood and tested anti-microbial agents. The efficacy of the known anti-microbial agents is amplified in the formulations of the invention. Therefore, anti-microbial agents that have a low toxicity can be used in the anti-microbial compositions. In contrast, many "new" anti-microbial agents for known techniques of sanitization use "stronger", more toxic and/or little tested materials.
The anti-microbial compositions of the invention do not contain 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.
The anti-microbial compositions of the invention do not interfere with the biochemical reproductive pathways of the micro-organisms they control. The risk of resistance build up and the development of resistant strains is, therefore, low.
The anti-microbial compositions of the invention can have a duel effect in that not only do they provide an anti-microbial effect in use but they can also have a preservative effect on the composition. This means that it is typically not necessary to include additional preservatives in the formulations of the invention.
The compositions of the invention do not typically give surfaces to which they are applied a greasy feel.
According to a further aspect of the invention, there is provided the use of composition of the invention to control, reduce or prevent the formation of colonies of micro-organisms on a surface at which it is provided. The present invention provides a method for providing a residual antimicrobial benefit to a surface such as a hard surface or skin, which method comprises applying a composition as defined herein to that surface. The composition may be applied to the surface by spraying the composition on the surface or wiping the composition onto the surface. In one method of the invention, it is not necessary for the method to include any steps in addition to simply applying the composition to the surface. Thus, a method that consists essentially of or consists of applying the composition to the surface is provided.
It will be appreciated that in order to also provide cleaning it may also be necessary to wipe or scrub the surface. Thus, the invention also provides a method in which the surface is wiped or scrubbed when the composition of the invention is applied to the surface.
The compositions of the invention can be used in the form in which they are provided or can be diluted with water before use. Thus, the invention also provides a method, such as a method as defined above, in which a composition of the invention is diluted before use.
The compositions of the invention that comprise a compound of formula (C) such as N,N- bis(3-aminopropyl)-dodecylamine are particularly useful for controlling or reducing or preventing the formation of fungi. The anti-microbial compositions of the invention 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.
The property of mobility of the product permits materials that are frequently washed or rinsed to be "recharged" with the anti-microbial composition during a routine act of cleaning or maintenance.
Typically, the anti-microbial composition is incorporated into a simple conventional detergent solution or added to a "final rinse" during cleaning. The anti-microbial composition will be drawn, due to the presence of its hydrophobic elements, into the surface of the product to be
"recharge". The sanitization properties of the formulation are, therefore, restored without the need for re-manufacture or difficult treatment processes.
Any wash off or rinsates containing the anti-microbial composition or formulation diluted by such a re-charging solution and water would quickly dissociate into the biodegradable components as previously discussed.
According to a further aspect of the invention, there is provided the use of an anti-microbial composition of the invention to reduce or prevent the formation of colonies of microorganisms on a surface at which it is provided.
The anti-microbial compositions of the invention are typically made by a process as described below. 1. The main bulk of the water (approximately 50 to 75% of the total amount of water used) is weighed into suitable vessel.
2. The chelate is added to the water and stirred until homogenous.
3. Optionally, if a polar solvent in addition to water is being used this is added and the mixture is stirred until homogenous.
4. In a separate vessel, a combination of non-ionic surfactant and amphoteric surfactant (if used) and fragrance (if used) is prepared and then added to the mixture obtained in step 4 and the mixture stirred until, homogenous.
5. If any cationic surfactants are used they are added and the mixture stirred until homogenous.
6. The quaternary ammonium compound(s) are added and the mixture stirred until homogenous.
7. The polymer is added and the mixture stirred until homogenous.
8. Water is added to 100% and the mixture stirred. The person of ordinary skill in the art would know how to adjust the pH of the composition. For example, if this method is being used to produce a high pH composition sodium carbonate and/or sodium bicarbonate and/or other suitable pH adjusters can be added in step 2. If this method is being used to produce a low pH composition, the pH can be adjusted by adding an acid to the composition between steps 7 and 8.
If the composition is to comprise an additional anti-microbial agent such as PHMB, this is added between steps 6 and 7.
The compositions may be prepared in a concentration form (i.e. with little or no polar solvent) and diluted with polar solvent (e.g. water) when used.
The present invention provides compositions obtainable by the process set out above.
Brief description of the Figures:
Figure 1 shows the results of the cleaning test reported in Example 6.
Figure 2 shows the results of the cleaning test reported in Example 7. The invention will now be illustrated by the following non-limiting Examples. Experimental Residual Efficacy Testing
Aim: Testing was carried out to determine the residual sanitising efficacy of antimicrobial products on non-porous stainless steel surface against certain microorganisms using abrasion steps and microbial challenges over a 24 hour period.
Equipment
Stainless steel coupons 2cm diameter, grade 304/1.4301 with grade 2B finish (as documented in EN13697:2001)
Tryptone soya agar (TSA), for anti bacterial efficacy testing
Malt Extract Agar (MEA), for anti fungal efficacy testing
Tryptone -saline diluent (as documented in EN1276-2009)
Bovine albumin (fraction V)
Vortex
Validated neutralisation solution
Sterile plastic containers > 3cm and < 5cm in diameter
Forceps
50ml centrifuge tube weighted to ~200g
Sterile petri dishes
Inoculating loops
70% (v/v) iso-propanol
Balance to at least 2 decimal places
LAF Class 2 Biologica Safety cabinet
Deionised water
Hard surface polypropylene wipes
Standard Hard water (as referenced in en1276:2009)
Incubator capable of 37°C ± 1 °C
Method
Preparation of steel coupons
Steel coupons (stainless steel discs) were rinsed thoroughly with clean hot water (tap water) to remove any contaminating dirt from the surface then rinsed for a few seconds with freshly deionised water. The cleaned coupons were sanitised by submerging in 70% (v/v) iso- propanol for 15 minutes. Using sterile forceps the coupons were transferred to sterile Petri dishes and dried by evaporation under laminar air flow by leaving the lid slightly ajar. Five replicates were used for each time point sampled plus a control set.
Abrasive Cycle
A 50ml centrifuge tube was weighted so that it weighed approximately 200g (+/- 20g). A professional care wipe was folded twice (4 layers) and wrapped over the lid of the centrifuge tube ensuring a smooth cover. An abrasive cycle consisted of a dry wipe followed by a bacterial challenge and a wet wipe followed by a bacterial challenge (as detailed below). a) Wet Wipe
This constituted an abrasion with a polypropylene hard surface wipe wrapped over the lid of a 50 ml centrifuge tube. The wipe was dampened by spraying a mist of standard sterile hard water, using a trigger spray (2 sprays, approximately 50 cm distance from the wipe). The tube was wiped in a forward and backward motion across the stainless steel coupon taking 2-3 seconds, allowing all the downward pressure to be provided by the weight of the centrifuge tube on the coupon surface. The wiped discs were then allowed to dry before the dry wipe cycle was carried out. b) Dry Wipe
Mechanism as in the wet wipe cycle however the wipe was not wetted. c) Bacterial challenge
The discs were then subject to a bacterial challenge using either a 106 CFU/ml (intermediate
time/ wear points) or 10 CFU/ml (0 and final wear cycles) concentration of the required bacterial suspension with an interferring substance. (See below for bacterial challenge preparation). Bacterial Challenge Preparation
A bacterial suspension was prepared fresh from a secondary subculture on TSA (subcultures prepared as documented in EN13697:2001). The bacterial suspension was diluted as necessary using tryptone saline, to give a cell concentration of approximately 108 CFU/ml suspension. The concentration of the bacterial suspension was determined using a colorimeter. The suspension was mixed 1:1 with bovine albumin soluion (0.6%) before use to achive a final concentration of 0.3% bovine albumin solution in the bacterial suspension. The 108 CFU/ml concentration of bacterial suspension was used for the initial and final bacterial challenges in the testing. For re-innoculations (included in the abrasion steps) the 108 CFU/ml suspension was further diluted to 106 CFU/ ml using tryptone-saline solution. The 106 CFU/ml suspension was mixed 1:1 with bovine albumin soluion (0.6%) before use to achive a final concentration of 0.3% bovine albumin solution in the bacterial suspension. Test Method (All testing performed using 5 replicates)
1. Time Ohr: 100μΙ of the product being tested or sterile hard water (for control coupons) was pipetted onto sterile coupons, ensuring the entire surface was covered by spreading the product with an inoculating loop. The coupon was left to dry on a level surface in a biological safety cabinet until completely dry at ambient temperature (21-23°C).
2. (0 wears) A control steel disc was assessed for initial antibacterial efficacy - 10 of the bacterial suspension (108 CFU/ml) containing 0.3% bovine albumin was added to the steel disc and after 5 minutes contact time, using sterile tweezers, the disc was placed into a vial containing 10ml neutraliser solution. The vial was shaken briefly to allow mixing, then left to stand for 5 minutes, after which time the vial was vortexed for 30 seconds. Serial dilutions (10"4) were then prepared in the neutralisation solution and plated out. Molten TSA was poured into the plates and allowed to set before incubation at 37°C for 48 hours.
3. Abrasion samples
1st abrasive wear cycle - Following the complete desiccation of the 100 μΙ of product (at least 3 hours) the steel coupons were subjected to their first abrasion wear cycle. This consisted of
a dry wipe followed by a bacterial challenge and a wet wipe followed by a bacterial challenge using a 106 CFU/ ml concentration of the bacterial suspension (0.3% bovine albumin concentration). 10 μΙ of the 106 CFU/ ml bacterial/ bovine albumin suspension was applied to the centre of the disc and gently spread using a sterile disposable loop. The discs were left to dry in a Petri dish in a safety cabinet. Once dried the lids were replaced and the discs left to stand until the next abrasive cycle was required.
2nd abrasive wear cycle - exactly as above 3rd abrasive wear cycle (24 hours). A dry wipe followed by a re-inoculation was performed before a final wet wipe was carried out on the discs and the antibacterial efficacy was determined as in the initial activity (0 wears) using the 108 CFU/ml bovine albumin bacterial suspension as follows. 10 μΙ of the 108 CFU/ml bacterial/bovine albumin suspension was added to the discs and after 5 minutes contact time, using sterile tweezers, the discs were placed into separate vials containing 10ml neutraliser solution. The vials shaken briefly to allow mixing, then left to stand for 5 minutes, after which time the vials were vortexed for 30 seconds. Serial dilutions to (10"4) were then prepared in the neutralisation solution and plated out. Molten TSA was poured into the plates and allowed to set before incubation at 37°C for 48 hours.
Neutraliser Validation:
A fresh batch of bacterial suspension was prepared (108 CFU/ml) in tryptone-saline solution from a secondary culture on TSA. The suspension was mixed 1:1 with 0.6% bovine albumin solutions to achieve a final concentration of 0.3% bovine albumin solution in the bacterial suspension.
For each product under test, 100 μΙ of product was pipette into a sterile container with 10 ml of neutraliser and gently mixed, left for 5 minutes. After the neutralisation the disc was inoculated with 10 μΙ of 108 CFU/ml of the antimicrobial test suspension and transferred to a vial and mixed well, the vial was allowed to stand for 5 minutes and vortexed for 30 seconds. Serial dilutions to 0"4 were prepared in the neutraliser solution and plated out. Molten TSA (Tryptone Soya Agar) was poured into the plate and allowed to set before being incubated at 37°C for 48 hours. TVC's (total viable counts of the bacteria grown in the agar) were obtained from the products and log 10 bacterial reductions calculated from discs treated with hard water as a control.
The compositions tested were considered to pass the test and provide a residual antimicrobial benefit if at the end of this test they gave a log 3 or greater bacterial reduction. EXAMPLE 1 : Simple formulations - Quats/ Chelate/ Surfactant - With and Without Polymer (Mirapol)
These results show that a formulation that does not contain a polymer (Mirapol Surf S110) does not provide residual antimicrobial performance against either Pseudomonas or E.coli. These results also show that a formulation containing all the essential ingredients of the compositions of the invention provide residual antimicrobial performance.
Experimental
Quat Blend Concentrate - RSH008/100A
In a suitably sized vessel Deionised Water (760.00g) was added, followed by the addition of DDQ (Acticide DDQ40) (200.00g) the mixture was left to stir for 10 minutes on a magnetic. The BAC (Acticide BAC50M) (40.00g) was then added and left to stir for a further 30 minutes.
Preparation of 12E
In a suitably sized vessel Deionised water (90.00g) was added, followed by the addition of Tetrasodium EDTA (Surfac Na4 EDTA Liquor - Surfachem) (0.2g) the mixture was left to stir
on a magnetic stirrer for 15 minutes. The C9-11 Alcohol Ethoxylate (Surfac UN9090 - Surfachem) (0.11g) was then added the mixture was left to stir for a further 15 minutes. The Quat blend (RSH008/100A - Byotrol) (7.00g) was then added and left to stir for a further 10 minutes. The pH was then checked and adjusted to approximately pH 4 using 88% Lactic Acid Sol (Fisher) (0.1g). Deionised water was then added to make sample up to 100g (4.61 g) and then stirrer for a further 15 minutes.
EXAMPLE 2: Low pH mixed surfactant formulations
Residual performance against Pseudomonas
These results show that compositions that do not comprise the polymer do not provide the desired level of residual anti-microbial performance. It is known that the addition of high levels of surfactant relative to the amount of quaternary ammonium compound can have an impact on the antimicrobial performance of a composition. The results of Sharp 3E show this effect, however, the addition of component (ii) the polymer and the chelate (v) provides a formulation that has a desirable level of residual antimicrobial performance (> 3 log).
Experimental for Sharp Series: Sharp 3B
In a suitably sized vessel Deionised Water approx. (78.35g) was added, followed by the addition of Dissolvine GL-47 (Brenntag) (0.2g) the mixture was then left to stir for 10 minutes
on a magnetic stirrer. The Alcohol Ethoxylate (Surfac UN9090 - Surfachem) (0.50g) and C10 Amine Oxide (Euroxide D40 - EOC) (1.0g) were then added and stirred for a further 15 minutes. After this the Quat blend (4:1 blend of DDAC and BAC) (14.0g) was added and the mixture stirred for a further 10 minutes. The Mirapol Surf S110 (Rhodia) (0.95g) was then added and stirred for a further 10 minutes. The pH was then checked and adjusted to approximately pH 4 using 8.8% Lactic Acid Sol (Fisher) (4.14g). Deionised water (0.86g) was then added to 100g and stirred for a further 15 minutes.
Samples Sharp 3A, C and E were made using the same procedure as for Sharp 3B but with the omission of the ingredients specified in the table.
EXAMPLE 3: Low pH mixed surfactant formulations with various chelates - Residual performance against Pseudomonas
Project Sharp 4: Sharp 4A
In a suitably sized vessel Deionised water (75g) was added, followed by the Alcohol Ethoxylate (Surfac UN9090 - Surfachem) (0.50g) and C10 Amine Oxide (Euroxide D40 - EOC) (1 0g) was then added and the mixture stirred for 15 minutes. After this the Quat blend
(4:1 blend of DDAC and BAC) (14.0g) was added and the mixture stirred for a further 10 minutes. The Mirapol Surf S110 (Rhodia) (0.95g) was then added and stirred for a further 10 minutes. The Tetrasodium EDTA (Surfac Na4EDTA Liquor) (0.4g) was then added and the mixture stirrered for a further 15 minutes. The pH was then checked and adjusted to approximately pH 4 using 88% Lactic Acid Sol (Fisher) (0.5g). Deionised water (7.65g) was then added to 100g and stirred for a further 15 minutes.
All other formulations were prepared in the same way as Sharp 4A using the alternative chelate.
EXAMPLE 4: High pH Formulations - Residual performance against Pseudomonas
These results show that in addition to improving residual antimicrobial performance, at high pH the chelate can also improve the clarity of the formulation. This is of particular interest in achieving an aesthetically favourable product.
The inventors have found that formulating with polymers of the types described herein can sometime cause clarity issues at higher pH (>4.5), in part due to the chemical nature of the
monomers. By selection of the surfactant, the chelate and the amount of these ingredients the clarity of the compositions can be improved.
Experimental Project Sharp 2: Sharp 2A (RSH008/96A)
In a suitably sized vessel Deionised Water (75g) was added, followed by the addition Sodium Carbonate (Fisher) (0.36g) and Sodium Bicarbonate (Fisher) (0.1 Og) the mixture was left to stir for 15 minutes on a magnetic stirrer. After this the Alcohol Ethoxylate (Surfac UN9090 - Surfachem) (0.5g) and C10 Amine Oxide (Euroxide D40- EOC) (2.00g) were added and left to stir for a further 30 minutes. The Quat Blend (4:1 blend of DDAC:BAC) (14.00g) was then added and stirred for a further 10 minutes. The Mirapol Surf S110 (Rhodia) (0.95g) was then added and stirred for a further 10 minutes, the solution becomes hazy at this point. The Chelate -Tetrasodium EDTA (Surfac Na4 EDTA Liquor- Surfachem) (0.4g) was then added and stirred for a further 15 minutes, solution cleared on addition of EDTA. The pH was then checked spec pH 9.50 - 10.00. Deionised water (6.69g) was then added to 100g and mixture was then stirred for a further 15 minutes. Sharp 2F was made in the same way with the omission of chelate.
At high pH there can be stability and clarity issues. The use of a chelate can help improve the clarity of a composition and its subsequent stability. The absence of a chelate (EDTA) can have a negative effect on the microbiological performance.
PH 9.85 9.76 10.02 10.07
Formulation comments Clear Clear Clear Clear
Microbiological results 1 >4.57 (0.47) >4.00 (0.84) >4.57 (0) 4.16 (0.89) (Pseudo) (735, 747)
These results show that the use of a polar solvent in addition to water can help improve the stability of the composition, especially if the composition contains a fragrance. The inclusion of such a solvent does not have a detrimental effect of residual anti-microbial performance. All of the compositions tested in this Example passed the test for residual antimicrobial benefit.
Experimental
Compositions Sharp 2E, 2G and 2H were made using the method described compositions Sharp 2A, with the additional of the solvent being added after the surfactant.
EXAMPLE 5: High pH formulations - with and without polymer (Mirapol) and with and without chelates - Residual performance against Pseudomonas
These results show that the absence of a chelate and/or a polymer can reduce residual antimicrobial efficacy. They also show that compositions that contain both a polymer and a chelate pass the test for residual antimicrobial benefit. Formulation Sharp 11 B contained no surfactants and as a result was an opaque solution, this is not desirable. Although desirable residual performance was achieved the samples that did not contain a surfactant would not be desirable due to poor cleaning performance. Formulation Sharp 2A shows a composition comprising all 4 essential ingredients required by the present invention has desirable residual antimicrobial performance and desirable cleaning ability (see Example 6). Experimental
The compositions were prepared as described above for the Sharp 2 series.
EXAMPLE 6: Comparison of the cleaning properties of high and low pH formulations with and without surfactants.
The results of this experiment are shown in Figure 1.
Line 1 - Sharp 2A - High pH composition comprising surfactant
Line 2 - Sharp 11B - High pH composition, no surfactant
Line 3 - Sharp 3A - Low pH composition, no surfactant,
Line 4 - Sharp 3B - Low pH composition comprising surfactant
The results show that surfactants are essential for cleaning and that high pH composition may provide slightly better cleaning than low pH compositions. Mixed surfactants may provide improved cleaning performance, particularly against a range of soils.
Procedure for Cleaning Tests (Use of Wet Abrasion Scrub Tester Re 903PG)
A white acrylic panel dosed with a composition of simulated bath soil (a combination of calcium carbonate, soap and grease) was loaded onto the Wet Abrasion Scrub Tester with the soiled side facing up. 4 sponges labelled 1-4, were soaked in cold water then squeezed out between 2 tiles. For each product 2 grams was dosed onto a sponge, recording which product was on which sponge. The sponges were the loaded into the Wet Abrasion Scrub Tester in sponge holders 1 to 4. 300 grams of extra weight was added to each sponge holder. The machine was set to 100 hundred wear cycles, and then started. Once the run was complete, the panel was removed from the machine and the level of soil removal assessed on tracks 1 to 4. The tracks were then marked between 0 and 10. 0 corresponds to no soil removal, 10 corresponds to complete soil removal.
Series 6: High pH with and without Surfactants
Series 6: Low pH with and without Surfactants
Example 7: Cleaning performance
The results of this experiment are shown in Figure 2.
Line 1 - Sharp 8A - Low pH composition, comprising polymer, no surfactant, no chelate Line 2 - Sharp 8B - Low pH composition, comprising polymer and chelate, no surfactant Line 3 - Sharp 8C - Low pH composition, no surfactant, no polymer, no chelate
Line 4 - Sharp 8D - Low pH composition comprising surfactant, chelate and polymer The results show that surfactants facilitate cleaning.
Experimental: Sharp 8D
In a suitably sized vessel Deionised Water (85g) was added, followed by the addition of Quat Blend (RSH008/100A- Byotrol) (7.0g) the mixture was then left to stir for 10 minutes on a magnetic stirrer. After this the Mirapol Surf S110 (Rhodia) (0.95g) was added and left to stir for a further 10 minutes. The Dissolvine GL-47(Brenntag) (0.20g) was then added and left to stir for a further 10 minutes. The C10 Amine Oxide (Euroxide D40 - EOC) (1.0g) and C9-11 Alcohol Ethoxylate (Surfac UN90 90 - Surfachem) (0.5g) were then added and the mixture stirred for a further 15 minutes. The pH was then checked and adjusted to approximately pH 3.5 using 88% Lactic Acid Sol (Fisher) (0.60g). Deionised water (5.75g) was then added to 100g and the mixture stirred for a further 15 minutes.
Compositions Sharp 8A, B and C were made using the same procedure but with the omission of the indicated ingredients.