WO2012013505A2

WO2012013505A2 - Composition

Info

Publication number: WO2012013505A2
Application number: PCT/EP2011/062008
Authority: WO
Inventors: Alexander Gordon James; David William Thornthwaite
Original assignee: Unilever Plc; Unilever N.V.; Hindustan Unilever Limited
Priority date: 2010-07-28
Filing date: 2011-07-13
Publication date: 2012-02-02
Also published as: WO2012013505A3

Abstract

Composition comprising oxalysine. Composition for reducing or prevent malodour comprising an effective antimicrobial amount of oxalysine. Use of oxalysine for the prevention or reduction of malodour. Use of oxalysine as an antimicrobial agent

Description

COMPOSITION

The present invention relates to a new antimicrobial composition. Despite the prior art there remains a need for further antimicrobial compositions.

Accordingly, and in a first aspect, the present invention provides a composition comprising oxalysine. Oxalysine is commercially available from Aldrich as (S)-(+)-2-Amino-3-(2- aminoethoxy)propanoic acid monohydrochloride (98%), catalogue number 510564. It has an assigned CAS number of: CAS 1 18021 -35-5.

Preferably, the oxalysine is L-4-oxalysine. More preferably, oxalysine is 2-amino- 3-(2- aminoethoxy)propanoicacid.

Preferably, the oxalysine is present at from 0.001 to 1 .5% wt. of the composition, more preferably from 0.1 to 1.0% wt. of the composition and most preferably from 0.3 to 0.6% by wt. of the composition.

In a second aspect there is provided a composition for reducing or preventing malodour comprising an effective antimicrobial amount of oxalysine.

The compositions of either aspect of the invention may take any form. Example compositions include wax-based sticks, soap-based sticks, compressed powder sticks, roll-on suspensions or solutions, emulsions, gels, creams, squeeze sprays, pump sprays, and aerosols. Each product form contains its own selection of additional components, some essential and some optional. The types of components typical for each of the above product forms may be incorporated in the corresponding compositions of the invention. A carrier material is an essential component of the compositions of the invention. For cosmetic applications, it is essential that the carrier material is cosmetically acceptable. The carrier material may be hydrophobic or hydrophilic, solid or liquid. Preferred carrier materials are liquids, meaning that they are in neither a solid nor a gaseous state and that they are able to flow under gravity at ambient temperature. Particularly preferred carriers materials are selected from the group consisting of liquid silicones and short chain (C2-C6) alcohols, such as ethanol.

References to ambient temperature in this description should be understood to refer to a temperature of about 23°C.

Liquid silicones are hydrophobic in nature and are frequently known as liquid polyorganosiloxanes. Such materials may be cyclic or linear, examples include Dow Corning silicone fluids 344, 345, 244, 245, 246, 556, and the 200 series; Union Carbide Corporation Silicones 7207 and 7158; and General Electric silicone SF1202. When the carrier material comprises a liquid silicone, it is common for the oxalysine to be present as a suspension in the carrier material.

Short chain (C2-C6) alcohols are often able to dissolve the oxalysine and it is common for said compound to be present in solution when the carrier material comprises such an alcohol. Preferred short chain (C2-C6) alcohols are

dipropylene glycol, glycerol propylene glycol, butylene glycol, ethanol, propanol, isopropanol, and industrial methylated spirits. Particularly preferred are ethanol and isopropanol, ethanol being the most preferred.

Alternatively or in addition to a short chain (C2-C6) alcohol, another organic solvent may be used as a carrier material, examples including polyglycol ethers, preferably oligoglycol ethers having only 2 to 5 repeat units. Alternatively or in addition to a silicone oil, a carrier material that is a non-silicone hydrophobic liquids may be used. Such materials include mineral oils,

hydrogenated polyisobutene, polydecene, paraffins, isoparaffins of at least 10 carbon atoms, aliphatic or aromatic ester oils (e.g. isopropyl myristate, lauryl myristate, isopropyl palmitate, diisopropyl sebecate, diisopropyl adipate, or Cs to C-I 8 alkyl benzoates), and polyglycol ethers, for example polyglycol butanol ethers.

Other hydrophilic liquid carrier materials, for example water, may also be employed. When water is employed, it is preferred that the pH of the formulation is near to neutral; that is to say, pH 6 to 8. Such pH values give optimum storage stability to the deodorant active and thereby lengthen the useful lifetime of the composition.

Mixtures of carrier materials may also be used. The total amount of carrier material employed is preferably at least 5%, more preferably from 30% to 99%, and most preferably from 60% to 98% by weight of the composition, excluding any volatile propellant present.

An essential component of compositions of the invention is a fragrance material. Suitable fragrance materials include conventional perfumes, such as perfume oils and also include so-called deo-perfumes, as described in EP 545,556 and other publications. These latter materials may also qualify as additional organic antimicrobial agents. Levels of incorporation are preferably up to 4% by weight, particularly from 0.1 % to 2% by weight, and especially from 0.7% to 1 .7% by weight of a composition. Synergies may exist between the oxalysine and the perfume - highly effective odour control being the result.

Particular compositions of the invention comprise a solution of the deodorant active in an organic solvent. Such solutions are preferably homogeneous, preferably having an absorbance, relative to the solvent, of less than 0.2, especially less than 0.1 (for a 1 cm pathlength at 600 nm) measured using a Pharmacia Biotech Ultrospec 200 Spectrophotometer or similar instrument.

Suitable organic solvents for use in this embodiment include the aforementioned short chain (C2-C6) alcohols.

When organic solvent is present in the composition, it is preferably present at from 30% to 98, more preferably at from 60% to 97% by weight of the composition, excluding any volatile propellant present. In embodiments of the invention in which the oxalysine is suspended in the carrier material, the oxalysine may have superior chemical stability.

In many compositions according to the invention, it is preferred that less than 10%, in particular less than 5%, and especially less than 1 % by weight of water is present. Such low levels of water can lead to an enhancement of the

performance of the oxalysine, in particular its performance after long term storage of the composition.

Deodorant actives other than oxalysine may also be present in compositions according to the invention. Such materials may be organic anti-microbial agents. Levels of incorporation of such materials are typically from 0.01 % to 3%, in particular from 0.03% to 0.5% by weight of the composition, excluding any volatile propellant also present. Most of the classes of agents commonly used in the art can be utilised, for example quaternary ammonium compounds, like

cetyltrimethylammonium salts; chlorhexidine and salts thereof; and diglycerol monocaprate, diglycerol monolaurate, glycerol monolaurate, and similar materials, as described in "Deodorant Ingredients", S.A.Makin and M.R.Lowry, in

"Antiperspirants and Deodorants", Ed. K. Laden (1999, Marcel Dekker, New York). More preferred additional deodorant actives are polyhexamethylene biguanide salts; 2,4,4'-trichloro,2'-hydroxy-diphenyl ether (triclosan); and 3,7, 1 1 - trimethyldodeca-2,6, 10-trienol (farnesol).

A particularly preferred additional deodorant active is a transition metal chelator, in particular a material having a high binding constant for iron (III); that is to say, a binding constant for iron (III) of greater than 10¹⁵, preferably greater than 10²⁰, and most preferably greater than 10²⁶, such materials being described in

EP 1 ,248,520 B (Unilever). A particularly preferred material of this class is diethylenetriaminepentaacetic acid (DTPA). Salts of such materials may also be employed. The total amount of transition metal chelator and/or salt thereof is preferably from 0.1 % to 5%, more preferably from 0.2% to 3%, and especially from 0.4% to 2% by weight of the composition.

Inorganic anti-microbial agents may also be present as additional deodorant actives. Such materials may also function as anti-perspirant actives. Typically, such materials are astringent metal salts, in particular, aluminium, zirconium and mixed aluminium/zirconium salts, including both inorganic salts, salts with organic anions and complexes. Examples of such astringent salts include aluminium, zirconium and aluminium/zirconium halides and halohydrate salts, such as chlorohydrates. When included, preferred levels of incorporation are from 0.5% to 60%, particularly from 5% to 30% or 40% and especially from 5% or 10% to 30% or 35% by weight of a composition.

Structurants and emulsifiers are further carrier materials that may be employed. Structurants, when employed, are preferably present at from 1 % to 30% by weight of a composition, whilst emulsifiers are preferably present at from 0.1 % to 10% by weight of a composition. Structurants include cellulosic thickeners such as hydroxy propyl cellulose and hydroxy ethyl cellulose, and dibenzylidene sorbitol. Other structurants include sodium stearate, stearyl alcohol, cetyl alcohol, hydrogenated castor oil, synthetic waxes, paraffin waxes, hydroxystearic acid, dibutyl lauroyl glutamide, alkyl silicone waxes, quaternium-18 bentonite, quaternium-18 hectorite, silica, and propylene carbonate. Emulsifiers include steareth-2, steareth-20, steareth-21 , ceteareth-20, glyceryl stearate, cetyl alcohol, cetearyl alcohol, PEG-20 stearate, dimethicone copolyol, and poloxamines.

Further emulsifiers desirable in compositions of the invention comprising perfume are perfume solubilisers. Examples include PEG-hydrogenated castor oil, available from BASF in the Cremaphor RH and CO ranges, preferably present at up to 1 .5% by weight, more preferably 0.3 to 0.7% by weight.

Other emulsifiers desirable in compositions of the invention are wash-off agents, for example poly(oxyethylene) ethers.

Certain sensory modifiers are further desirable components in the compositions of the invention. Such materials are preferably used at a level of up to 20% by weight of a composition. Emollients, humectants, volatile oils, non-volatile oils, and particulate solids which impart lubricity are all suitable classes of sensory modifiers. Examples of such materials include cyclomethicone, dimethicone, dimethiconol, isopropyl myristate, isopropyl palmitate, talc, finely divided silica (e.g. Aerosil 200), polyethylene (eg. Acumist B18), polysaccharides, corn starch, C12-C15 alcohol benzoate, PPG-3 myristyl ether, octyl dodecanol, C7-C14 isoparaffins, di-isopropyl adipate, isosorbide laurate, PPG-14 butyl ether, glycerol, hydrogenated polyisobutene, polydecene, titanium dioxide, phenyl trimethicone, dioctyl adipate, and hexamethyl disiloxane.

It should be noted that certain components of compositions perform more than one function. Such components are particularly preferred additional ingredients, their use often saving both money and formulation space. Examples of such components include ethanol, isopropyl myristate, and silica. Further additional components that may also be included are colourants and preservatives, for example C1 -C3 alkyl parabens.

Aerosol compositions according to the invention generally comprise a volatile propellant. The level of incorporation of the volatile propellant is typically from 30 to 99 parts by weight and particularly from 50 to 95 parts by weight. Non- chlorinated volatile propellant are preferred, in particular liquefied hydrocarbons or halogenated hydrocarbon gases (particularly fluorinated hydrocarbons such as 1 , 1 -difluoroethane and/or 1 -trifluoro-2-fluoroethane) that have a boiling point of below 10°C and especially those with a boiling point below 0°C. It is especially preferred to employ liquefied hydrocarbon gases, and especially C3 to Ce hydrocarbons, including propane, isopropane, butane, isobutane, pentane and isopentane and mixtures of two or more thereof. Preferred propellants are isobutane, isobutane/isopropane, isobutane/propane and mixtures of isopropane, isobutane and butane.

Other propellants that can be contemplated include alkyl ethers, such as dimethyl ether or compressed non-reactive gases such as air, nitrogen or carbon dioxide. Compositions according to the invention may be prepared by suspending or dissolving the active in a cosmetically acceptable carrier material, preferably with sufficient agitation to achieve a homogeneous mixture. When the oxalysine is suspended in the carrier material, it is preferred that it is first ground to a mean particle size of less 100 microns. The fragrance material is preferably added to the composition after the oxalysine has been dissolved or suspended in the carrier.

In a third aspect there is provided the use of oxalysine for the prevention or reduction of malodour. In a fourth aspect there is provided the use of oxalysine as an antimicrobial agent. EXAMPLE Standard 5 & 24hr deodorancy test protocol was conducted.

A = Unfragranced ethanolic roll-on control

B = Unfragranced ethanolic roll-on + 0.3% Oxalysine 35 subjects participated in both the 5 hour and 24 hour tests.

Mean Malodour Score Mean Dosage (300mg)

5hr 24hr

A 2.23 2.42

B 2.36 2.54

Difference for significance @ 95% 0.09 0.10

Difference for significance @ 99% 0.12 0.13

At 5 hours: Oxalysine is superior to control with 99% confidence.

At 24 hours: Oxalysine is superior to control with 95% confidence.

Claims

1 . Composition comprising oxalysine.

2. Composition according to claim 1 wherein the oxalysine is present at from 0.001 to 1 .5% wt. of the composition.

3. Composition for reducing or prevent malodour comprising an effective antimicrobial amount of oxalysine.

4. Use of oxalysine for the prevention or reduction of malodour.

5. Use of oxalysine as an antimicrobial agent.