Drug – bio-affecting and body treating compositions – Anti-perspirants or perspiration deodorants
Reexamination Certificate
2001-10-17
2004-01-20
Wilson, James O. (Department: 1623)
Drug, bio-affecting and body treating compositions
Anti-perspirants or perspiration deodorants
C424S066000, C424S400000, C424S401000, C536S123130
Reexamination Certificate
active
06680048
ABSTRACT:
The present invention relates to esters and in particular to esters of cellobiose, compositions containing them, and their use as structurants.
BACKGROUND
Many compositions intended for topical application to skin, including a number for various parts of the body, such as face, gums, hands, limbs, feet, torso, underarm, breasts, genitalia, hair and other parts of the body, comprise one or more active agents are distributed within or otherwise supported by a carrier fluid. Although it is possible, in many instances, that such compositions are in the form of lotions, it is often desirable that the active ingredient in such compositions, be it for medical or for cosmetic purposes, remains substantially localised in the region of the body to which it has been topically applied. In order to assist this to happen and also to enable alternative dispensers for the composition to be employed, the carrier fluid can be thickened or structured, for example by introducing one or more materials for that purpose. Thickened or structured compositions commonly adopt the form of firm sticks, or soft solids and creams. In such circumstances, the materials are often referred to as structurants or gelants and may sometimes alternatively as thickeners, depending on the final form of the composition. The carrier fluid may comprise water and/or a water-miscible organic liquid and alternatively or additionally a water-immiscible liquid.
In general, the choice of structurants or thickeners tends to vary in accordance with the physical nature of the carrier fluid and in particular on whether it is water-miscible or immiscible. The present invention is directed more particularly towards materials which are capable of structuring a water-immiscible liquid, which may act by itself as carrier for an active ingredient or comprise a water-immiscible phase in an emulsion or micro-emulsion or a liquid crystalline phase.
Many materials have been proposed for structuring or thickening a water-immiscible liquid phase of a composition intended for topical application to humans. These have included waxes natural waxes, such as paraffin waxes or those typically extracted from vegetation, such as candelilla wax, or glyceride waxes, or produced by chemical treatment of natural oils, for example hydrogenation of castor oil, or produced by extracted from fauna, such as beeswax or spermaceti wax, or derivatives or synthetic variants of them. Others include fatty alcohols, e.g. linear C18 or C22 alcohols. Other materials are polymeric, such as polysiloxane waxes, or polysiloxane elastomers, or various polyamide/polysiloxane copolymers.
In the closing years of the 20th century, a number of structurants were identified which the present inventors classify as fibre-forming. These include 12-hydroxy stearic acid, various amino acid amides, including particularly, combinations of sterols and sterol esters, for example, particularly, &bgr;-sitosterol and &ggr;-oryzanol, derivatives of threitol, diamide derivatives of cyclohexane, and acylated derivatives of cellobiose. Each of the various structurants has to a greater or lesser extent its particular benefits and its intrinsic disadvantages, either in absolute or relative terms. These properties can include the ability of the material to gel or otherwise structure the carrier liquid, including the resultant hardness and stability, and the sensory properties and appearance of the resultant composition, being of great importance for cosmetic compositions.
One of the most desirable class of structurants comprises acylated cellobiose, as described in PCT application No PCT/GB 00/01228, published as WO 00/61079, particularly for structuring a water-immiscible liquid in a cosmetic compositions, including especially antiperspirant and deodorant compositions. In said PCT application, it has been disclosed that the cellobiose can adopt either an &agr; or &bgr; configuration, preferably the former, and various preferences are given for both the number of acyl substituents of the cellobiose nucleus and the chemical constitution of such substituents. Nonanoate esters of cellobiose (sometimes abbreviated to CB9) and particularly cellobiose octanonanoate in the predominantly &agr; configuration is described therein as the most highly preferred acylated cellobiose, because CB9, particularly cellobiose octanonanoate, and specifically the &agr; anomer is capable of structuring water-immiscible liquids that demonstrate an excellent combination of properties, namely high clarity and acceptable hardness when they are made.
However, it has been found that some samples of water-immiscible liquids which had been structured successfully using &agr; anomeric CB9 tended to suffer from a loss of clarity after extended periods of storage and/or to exhibit some loss of structural strength. Either effect conveys self-evident disadvantages. Manifestly, if the stored product loses its structural strength, it can disintegrate under pressure. Alternatively an impairment in clarity is a visual cue which can be equated by consumers to impaired product performance. Formulations such as cosmetic formulations can take a long time to pass through conventional distribution channels or can sometimes remain unused for several months in consumers' homes.
Accordingly, it would be desirable to find a way to ameliorate or overcome the foregoing long-term disadvantages of &agr; anomeric CB9 whilst at the same time retaining the capability of the material to act as a good structurant for water-immiscible liquids, and especially in the presence of a dispersed phase. It would be of only limited benefit if a solution that addressed the foregoing disadvantages on storage of CB9 structured formulations resulted in significant impairment of other and beneficial properties of the structured product.
It is an object of the present invention to provide an acylated cellobiose which demonstrates an attractive combination of properties in comparison with such &agr; anomeric CB9, particularly in the context of acting as a structurant for a water-immiscible liquid.
Other and further objects of the present invention or aspects or embodiments thereof can be deduced from the disclosures hereinafter.
Research conducted by the instant inventors indicates that CB9 is a mixture of compounds which are present in varying proportions, depending on the method of manufacture and extent of blending. The overall properties of the mixture likewise vary. Three identifiable sub-classes of compounds have been found which contribute to the variation in properties. One sub-class comprises compounds in which the anomeric carbon is substituted by the nonanoate group in the axial orientation, called herein the &agr; anomer, the second sub-class comprises compounds in which the anomeric carbon is substituted by the nonanoate group in the equitorial orientation, called herein the &bgr; anomer, and the third sub-class comprises compounds in which the anomeric carbon is substituted by an hydroxyl group.
In particular, it has been found that the objects of the present invention can be achieved by suitable selection simultaneously of two parameters of CB9. One parameter comprises the proportion of the &agr; anomer compared with the &bgr; anomer and the second parameter comprises the proportion of the hydrocarbon-containing substituent at the anomeric carbon in the acylated cellobiose structurant.
It will be understood, however, that although the material of the instant invention is contemplated especially for use in cosmetic formulations, its potential use is much wider, including the structuring of a water-immiscible liquid to make a cream, soft solid or stick for any other purpose. Such other purposes could include topical medicaments, topically applied veterinary products or animal cosmetics and waxes or polishes.
BRIEF DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, there is provided an acylated cellobiose which contains n-nonanoate acyl substituents of the cellobiose rings characterised in that the percentage Y of the nonano
Grainger Lynda
Gransden Kathryn Elizabeth
Hopkinson Andrew
Kowalski Adam Jan
Webb Nicholas
Maier Leigh C.
Stein Kevin J.
Unilever Home & Personal Care USA a division of Conopco, Inc.
Wilson James O.
LandOfFree
Esters does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Esters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Esters will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3211699