GB2303789A - Perfumed compositions containing formaldehyde generating preservatives - Google Patents

Abstract

Cosmetic, personal care and liquid detergent compositions contain i) a formaldehyde generating preservative, e.g. DMDM Hydantoin and; ii) at least 0.1 % perfume which comprises less than 50 x 10 -5 moles enolisable aldehyde, e.g. octanal, heptanal or hydroxycitronellal, per gram of perfume. This low enolisable aldehyde content improves the stability of the perfume and thus the storage stability of the inventive compositions.

Description

PERFUMED COMPOSITIONS Fleld ofthe Invention The present invention relates to cosmetic, personal care and liquid detergent compositions and more particularly, to perfumed cosmetic , personal care and liquid detergent compositions containing a formaldehyde generating preservative which are stable upon long-term storage.

Background of the Invention Most cosmetic, personal care and liquid detergent compositions e.g.

shampoos, bath foams, skin creams, washing-up liquids and the like, contain ingredients that are susceptible to microbial spoilage e.g. surfactant molecules, emollient oils, perfumes. Such spoilage can not only compromise the designed performance of the product but also, in extreme cases, present a health hazard to the user of the product. Of course, manufacturers of such products take stringent precautions to prevent microbial contamination of their products during manufacture and distribution. Once the product package has been opened however, the contents may be open to inadvertent contamination by the user or e.g. through airborne spores.

It is customary, therefore, to add a preservative to such products at the time of manufacturing in order to protect the product against microbial contamination in the long term. A wide variety of such preservatives are known and used. The precise choice of type and level of the preservative is usually made by the formulator based upon a number of factors including, for example, the microbiological requirements of the product, cost, the pH of the product, compatibility with the other formulation ingredients, and regulatory restrictions. A guide to the factors used in preservative selection and testing can be found in 'Cosmetic and Drug Preservation, Vol.l, Principles and Practice', published by Marcel Dekker Inc..

One popular class of preservatives includes formaldehyde and those compounds capable of releasing formaldehyde, the latter including DMDM hydantoin and imidazolidinyl urea. However, regulatory restrictions often now limit the amount of formaldehyde that can be used. It is important, therefore, that the preservative used is able to act to its full potential over the lifetime of the product i.e. that it does not degrade or otherwise become inactive.

It has now been found that, in many formulations, especially in perfumed formulations, the formaldehyde level may decay on storage from its initial value. The rate and extent of the formaldehyde decay has been found to be a function of the type of perfume used. It can also be influenced by other ingredients within the formulation, for example by the type of surfactant used. In particular, certain aldehydic compounds, commonly used as perfume ingredients, are especially detrimental to the formaldehyde stability.

Without wishing to be bound by theory, the applicant believes that the aldehydic components react irreversibly with the formaldehyde, making it unavailable for use as a preservative. Such a reaction may have a further negative consequence in that it could also alter the olfactory character of the perfume.

It is accordingly an object of this invention to provide perfumed, cosmetic, personal care and liquid detergent compositions that are stable upon longterm storage.

It is a further object of the invention to provide perfumed, cosmetic, personal care and liquid detergent compositions which preserve the original character of the perfume.

Summary of the Invention According to one aspect of the present invention there is provided a cosmetic, personal care or liquid detergent composition comprising: a) an acceptable base; b) at least 0.1% perfume; and c) a formaldehyde generating preservative; characterised in that the perfume comprises less than 50 x 10-5 moles enolisable aldehydes per gramme of the perfume.

All levels and ratios are by weight of total composition, unless otherwise indicated.

Detailed Description of the Invention The compositions of the invention include as an essential feature a perfume comprising less than 50 x 10-5 moles enolisable aldehydes per gramme ofthe perfume.

As used herein the term 'perfume' refers to a composition which comprises materials which are used primarily to impart a desirable odour to the cosmetic, personal care or liquid detergent product. These materials, generally of an oily or lipophilic nature, can be natural products such as essential oils, absolutes, resins, etc., or synthetic perfume components such as hydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters, acetals, ketals, nitriles etc., including saturated and unsaturated compounds, aliphatic, carboxylic and heterocyclic compounds.Examples of such perfume components are: geranyl acetate, linalyl acetate, citronellyl acetate, dihydromyrcenyl acetate, terpinyl acetate, tricyclodecenyl acetate, tricyclodecenyl propionate, 2-phenylethyl acetate, benzyl acetate, benzyl salicylate, benzyl benzoate, styrallyl acetate, amyl salicylate, methyl dihydrojasmonate, phenoxyethyl isobutyrate, neryl acetate, trichloromethylphenylcarbinyl acetate, p-tertiary butyl-cyclohexyl acetate, isononyl acetate, cedryl acetate, vetiveryl acetate, benzyl alcohol, 2-phenylethanol, linalool, tetrahydrolinalool, citronellol, dimethylbenzylcarbinol, dihydromyrcenol, tetrahydromyrcenol, terpineol, eugenol, geraniol, vetiverol, 3-isocamphylcyclohexanol, 2-methyl-3 -(p-tertiary butylphenyl)-propanol, 2-methyl-3-(p sopropylphenyl)-propanol, 3 -(p-tertiary butylphenyl)-propanol, nerol, alphan-amylcinnamic aldehyde, alpha-hexyl-cinnamic aldehyde, 4-(4-hydroxy-4methylpentyl)-3-cyclohexenecarbaldehyde, 4-(4-methyl-3-pentenyl)-3 - cyclohexenecarbaldehyde, 4-acetoxy-3-pentyl-tetrahydropyran, 2-n-heptylcyclopentanone, 3-methyl-2-pentyl-cyclopentanone, n-decanal, n-dodecanal, hydroxycitronellal, phenylacetaldehyde dimethyl acetal, phenylacetaldehyde dimethyl acetal, geranonitrile, citronellonitrile, cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine, heliotropine, coumarin, vanillin, diphenyl oxide, ionones, methyl ionones, isomethyl ionones, irones, cis-3hexenol and esters thereof, indane musks, tetralin musks, isochroman musks, macrocyclic ketones, macrolactone musks, ethylene brassylate, aromatic nitromusks. The perfume composition can further include suitable extenders and diluents, for example: diethyl phthalate, triethyl citrate, etc.. In general, compositions of the invention will have a total perfume content of from about 0.1% to about 20%, preferably from about 0.3% to about 15%, more especially from about 0.5% to about 5%. The compositions of the invention are especially advantageous where the perfume content is greater than 1%.

The term 'enolisable aldehyde', as used herein, means a compound of the general formula (I)

wherein R1 and R2 may independently be hydrogen, alkyl, aryl, alkenyl, acyl, alkylamino and the like such that under suitable conditions the enol form (II) may be formed. R1 and R2 may also be joined such that they form part of a cyclic grouping including the alpha-carbon shown.

Examples of such enolisable aldehydes, useful as perfume components, include octanal (R2 = H, R1 = n-hexyl) and homologues such as heptanal, decanal and the like, hydroxycitronellal (R2 = H, R1 = 1,5-dimethyl-5hydroxyhexyl), phenylacetaldehyde (R2 = H, R1 = phenyl), cyclamen aldehyde (R2 = Me, R1 = p-isopropylphenyl) and isocyclocitral (III) wherein R1 and R2 form part of the same moiety.

Other examples of such enolisable aldehydes will be readily apparent to those skilled in the art. Preferably, the perfume comprises less than 30 x more preferably less than 15 x 10-5 moles enolisable aldehydes per gramme of the perfume. In especially preferred embodiments the perfume comprises less than 5 x 10-5 moles enolisable aldehydes per gramme of the perfume. In general, the more perfume is used in the cosmetic, personal care or liquid detergent compositions of the invention, the lower is the preferred level of enolisable aldehydes within the perfume from the point of view of formaldehyde stability. Ideally, the perfume is essentially free of enolisable aldehydes, although olfactory considerations may make a low level (e.g.

about 0.5 to about 10, especially about 1 to about 4 x 10-5 moles enolisable aldehydes per gramme of the perfume) desirable. The level of such components within a complex mixture can conveniently be estimated using 1H NMR spectroscopy, using pyridazine as a standard. The aldehydic hydrogen atoms resonate as doublets, triplets or quartets with chemical shifts generally in the range from about 9 to about 11 ppm.

A second essential component of the composition of the invention is a formaldehyde generating preservative. As used herein, the term 'formaldehyde generating preservative' means materials which either consist essentially of formaldehyde in solution or are capable of generating formaldehyde through decomposition within the medium of the composition of the invention.

Suitable materials for use herein are formalin (a 40% aqueous solution of formaldehyde); DMDM hydantoin, commercially available as GlydantS from Lonza Inc.; Glydant Plus, a commercially available mixture of DMDM hydantoin with iodopropynyl butylcarbamate;MDM hydantoin, available as Dantoin MDMHS from Lonza Inc.; imidazolidinyl urea, available as Germall 1 iso from Sutton Laboratories; diazolidinyl urea, available as Germall IIS from Sutton Laboratories; 5-bromo-5-nltro-1,3-dioxane, available as Bronidox LS from Henkel; 2-bromo-2-nitropropane-1,3-diol; glutaraldehyde; 7-ethylbicyclooxazolidine, available as Oxaban-E from Angus Chemical; quaternium-15, available as Dowicil 200 from Dow Chemical; and mixtures thereof.The precise choice and level of the preservative will be selected by the formulator based upon the microbiological requirements of the product, cost, the pH of the product, compatibility with the other non-pertume ingredients, regulatory restrictions and other factors. A guide to the factors used in preservative selection and testing can be found in 'Cosmetic and Drug Preservation, Vol.l, Principles and Practice', published by Marcel Dekker Inc.. In general, the level of preservative used in the compositions of the invention will be chosen so as not to exceed 2000 ppm of formaldehyde equivalents, preferably less than 500 ppm of formaldehyde equivalents is used. Preferred formaldehyde generating preservatives for use herein are DMDM hydantoin, imidazolidinyl urea, 5-bromo-5-nitro-l,3-dioxane and mixtures thereof.

The compositions of the invention can, optionally, further comprise nonformaldehyde-generating preservatives such as methyl or propyl paraben.

The compositions of the invention are cosmetic, personal care or liquid detergent compositions which take the form of shampoos, bath foams, skin creams, washing-up liquids and the like and further comprise an acceptable base suited to the product type. Typical formulations and methods of preparation for cosmetic and personal care compositions can be found in "Harry's Cosmeticology".

Cleansing compositions such as shampoos, bath foams, shower gels and washing-up liquids generally comprise one or more surfactants. These surfactants can be of the nonionic or ionic (cationic, anionic, amphoteric) type. Suitable anionic surfactants include the sodium, potassium, ammonium or alkylammonium salts of alcohol sulphates, alcohol ether sulphates, sulphosuccinates and isethionates. Cationic surfactants suitable for use herein comprise quaternary ammonium compounds and amine oxides e.g.

lauryldimethylamine oxide. Particularly suitable amphoteric surfactants are betaines such as cocoamidopropyl betaine.

It has now also been found that formaldehyde stability in perfumed compositions is adversely affacted by the presence of an ammonium, alkylammonium or alkanolammonium based salt. Frequently, ammonium, alkylammonium or alkanolammonium surfactants are used in such compositions.

The present invention is, therefore, of particular utility where an ammonium, alkylammonium or alkanolammonium based salt, particularly a surfactant, is used, especially ammonium, mono- or dialkylammonium or mono- or dialkanolammonium surfactants. Ammonium , alkylammonium or alkanolammonium neutralised surfactants are useful in the compositions of the invention at levels of from about 1% to about 15%, preferably at levels of from about 3% to about 10%. Suitable examples of such surfactants include, but are not limited to, ammonium laureth-3 sulfate, monoethanolamine laureth sulfate and diethanolamine laureth sulfate.Nevertheless, the perfumes according to the invention are suitable for use in the manufacture of a wide variety of cosmetic, personal care and liquid detergent compositions and particularly for those applications where other factors may make the choice of a non-formaldehyde-generating preservative unsuitable.

Examples Examples I and II are perfumes illustrative of the present invention.

l II Perfiime component % Triethyl citrate 14.5 15.5 2-Phenylethanol 14.1 14.9 Citronellol 10.6 10.6 4-Isopropyl cycylohexanol 8.1 8.

Benzyl acetate 5.8 5.8 Trimethylcyclododecenyl acetate 5.8 5.8 Linalool 5.5 5.5 Diethyl phthalate 5.3 5.

Hexyl cinnamic aldehyde 5.1 5.

Amyl salicylate 5.0 5. Musk ketone 5.0 5.0 Tetra-hydro linalool 4.5 4.5 Amyl cinnamic anhydride 4.0 4.0 Geraniol 2.1 2.1 Isopropyl myristate 2.0 2.0 p-tert-Butyl-a-methyl- 1.2 0.3 hydrocinnamaldehyde Hydroxycitronellal 0.9 0.2 Lauric aldeyhyde 0.3 0.2 Undecylenic aldehyde 0.2 0.1 Total 100 100 Examples III to VI are personal cleansing compositions in the form of shower gel or bath foam products and which are representative of the present invention. However, the invention is not limited thereto.

III IV V VI % % % % Sodium lauryl sulphate 4.0 4.0 2.0 2.0 Ammonium laureth-3 sulfate 10.0 - - 5.0 Cocoamphodiacetate 3 3.0 3.0 Polymer JRA00(RTM) 0.1 0.1 0.1 0.1 Perfume It 1.5 - 1.0 Perfume - 1.5 - 2.0 DMDM Hydantoin 0.2 0.2 Germall 115 0.2 0.2 Water < --- -to 100% - > t Perfumes I and II are taken from examples I and II above. They comprise, respectively, 13.9 x 10-5 and 4.3 x 10-5 moles enolisable aldehydes per gramme of the perfume.

The cosmetic, personal care and liquid detergent compositions of the invention have good long-term microbiological stability and a stable perfume character.

Claims (9)

1. A cosmetic, personal care or liquid detergent composition comprising: a) an acceptable base; b) at least 0.1% perfume; c) a formaldehyde generating preservative; characterised in that the perfume comprises less than 50 x 10-5 moles enolisable aldehydes per gramme of the perfume.

2. A composition according to Claim 1 wherein the perfume comprises less than 30 x 10-5, preferably less than 15 x 10-5, more preferably less than 5 x 10-5 moles enolisable aldehydes per gramme of the perfume.

3. A composition according to Claim 1 or Claim 2 wherein the composition comprises from 0.3% to 15%, preferably from 0.5% to 5%, more preferably from 1% to 5% ofthe perfume.

4. A composition according to any of Claims 1 to 3 wherein the composition further comprises an ammonium, alkylammonium or alkanolammonium salt.

5. A composition according to Claim 4 wherein the salt is an ammonium, alkyl ammonium or alkanolammonium surfactant.

6. A composition according to Claim 5 wherein the surfactant is an ammonium surfactant.

7. A composition according to any of Claims 1 to 6 wherein the formaldehyde generating preservative is selected from DMDM hydantoin, imidazolidinyl urea, 5-bromo-5-nitro-1,3-dioxane and mixtures thereof.

8. Use, as a formaldehyde-compatible perfume, of a perfume comprising less than 50 x 10-5 moles enolisable aldehydes per gramme of the perfume, in the manufacture of a cosmetic, personal care or liquid detergent composition comprising: a) an acceptable base; b) at least 0.1% perfume; c) a formaldehyde generating preservative.

9. Use according to Claim 8 wherein the composition comprises from 0.3% to 15%, preferably from 0.5% to 5%, more preferably from 1% to 5% of the perfume.