Antimicrobial preservative compositions for personal care products

Abstract

A personal product antimicrobial preservative composition for preservation of topical personal care formulations is provided comprising [A] one or more undecylenic acid derivatives depicted by Formula (I),[B] one or more octanoic acid derivatives depicted by Formula (II),and [C] 2-phenoxy ethanol or 2-ethyl hexyl glyceryl ether or mixture of these two ‘liquid alcohol ethers’; wherein, each of the two components [A] and [B] is present in the range of 5 to 20% by weight and together [A] and [B] constitute 10 to 30% by weight and the ‘liquid alcohol ether’, component [C], is present 70 to 90% by weight of the total preservative composition. A method for preserving personal care product from microbial attack is provided containing an aqueous phase comprising three component composition from about 0.5 to 2.5% by weight of the total personal care formulation.

Description

FIELD OF THE INVENTION[0001]The present invention relates to the preservation of personal care formulations with synergistic blends of three types of ingredients that offer a broad spectrum of activity against the microbes namely, an undecylenic acid derivative of Formula (I), an octanoic acid component of Formula (II) and a liquid alcohol ether, 2-phenoxy ethanol or 2-ethyl hexyl glyceryl ether or blend of the two. Further, the invention relates to the use of the combinations of three types of cosmetic ingredients.BACKGROUND AND PRIOR ART OF THE INVENTION[0002]Preservation of personal care products from microbial contamination has become a difficult task since the available approved antimicrobials are very few and those which have good antimicrobial activity are quite toxic. Consumers want products meant for topical applications to be free from toxic antimicrobials that are used as preservatives. This situation is partly addressed by exploiting the synergy between disparate of anti...

AI Technical Summary

Benefits of technology

This patent text describes a new preservative blend for personal care formulations that has three components and is designed to work together to prevent the growth of bacteria and other microbes. The blend does not contain any harmful substances like formaldehyde.

Problems solved by technology

Preservation of personal care products from microbial contamination has become a difficult task since the available approved antimicrobials are very few and those which have good antimicrobial activity are quite toxic.

Chloroxylenol is significantly toxic to mammals and is a skin irritant with quite allergic properties.

However, during 1998 to 2004 a few scientific publications implicated parabens in endocrine disrupting estrogenic activity and some other deleterious effects on reproductive systems in various test methods.

However, this clean chit does not seem to be adequate to mitigate the grave concern about the usage of parabens as preservatives.

Due to the paucity of effective and well-accepted antimicrobials, the industry is forced to continue with the using formaldehyde donors like DMDM hydantoin, imidazolidinyl urea, and diazolidinyl urea.

This is a big disadvantage for sunscreen formulations.

Quaternary ammonium antimicrobials: The third category of the quaternary ammonium compounds (examples are cetyl pyridinium chloride, benzethonium chloride, benzalkonium chloride, polyaminopropyl biguanide), has been of limited use for personal care industry due to specific incompatibilities with other cosmetic ingredients.

It is common knowledge that like phenolic compounds, the halogenated organic molecules exhibit significant levels of toxic effects.

For example, IPBC has risk of thyroid hormonal disturbances due to its iodine content.

But the toxicity of such powerful anti-microbials is extremely high and hence cosmetic formulators do not prefer to use this kind of powerful antimicrobial in the cosmetics that remain on human skin for a long time.

So far there is very little success with the search of a new safe ideal molecule and all the major manufacturers of antimicrobial preservatives for cosmetics continue to manufacture and sell preservative blends with either parabens or with formaldehyde donors.

Preserving personal care products from microbial degradation is quite challenging.

Thus, the requirement for the preservation of the personal care products is indeed quite challenging.

This is further compounded by the limited choice of antimicrobials.

Most antimicrobials available today for preservation of personal care products are not the ideal ones.

Bad press (suspected endocrine disrupting activity) for the parabens forced antimicrobial manufacturers and the cosmetic industry to search for the alternatives to paraben.

Though discovering a new powerful and toxicologically safe broad spectrum antimicrobial is possible, it is a long and expensive process to discover new material and have it approved by the Cosmetics Directives and accepted by the global markets.

In summary, the antimicrobial manufacturers do not seem to be looking to invent the ‘ideal’ preservative but synergistic combinations of antimicrobials to avoid parabens or formaldehyde donors.

A limitation of low molecular weight organic acids is that they are effective in acid form and hence only at low pH show efficacy as antimicrobial preservative.

However, again, using enzymatic compositions as preservative for personal care product may not be globally accepted since the enzymes used are glucose oxidase and lactoperoxidase.

Although several undecylenic acid derivatives have been reported to possess some antifungal activity, these have not been exploited commercially for the preservation of personal care formulations.

However, the significant limitation of using lipidated amino acid like undecylenoyl glycine is that they show effectiveness only when present in carboxylic acid form.

This is a severe limitation that pH of the cosmetic formulation has to be on the acidic side (WO 99 / 27902 / EP 0983055B1).

In summary, personal care industry has limited choice of anti-microbial agents that can be safely used for preservation of formulations that are accepted by the end consumers.

These requirements are not easily addressed by designing a new antimicrobial molecule because it takes at least a decade before a globally accepted molecule is born.

This is simply because there is no effective and efficacious alternative preservative system available that would replace them.

Preservative industry's efforts in this direction have been met with little or no success at all.

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