Patent Application
20110192412
The present invention relates to a hair grooming device and a formulation for use therewith.
The present invention is concerned with the problem of deposition of a benefit agent, particularly high molecular weight silicone from a hair grooming device.
Accordingly, the present invention provides a hair grooming device comprising a head, a nebuliser, a power supply therefore and a reservoir containing a composition to be applied to the hair during use by the nebuliser, the composition an emulsified composition wherein the viscosity of the emulsion is less than 8 cSt 25° C.
Preferably the head is bristle or tooth-bearing, more preferably the device is a comb or brush. Most preferably it is a brush.
The nebuliser is selected from those known in the art. Preferably, the nebuliser comprises a gauze defined by a rigid ring, a reservoir for containing a composition to be nebulised and a circuit connected to the power supply. Such a nebuliser is commercially available from Aerogen®.
Preferably, the gauze is convex with regard to the reservoir. This improves the movement of the nebulised fluid on to the hair during use.
Preferably, the nebuliser is located within the head and the head also comprises an aperture for releasing the nebulised fluid during use on to the hair. Preferably, the aperture is a hole or slot in the head. In a preferred embodiment there is a plurality of apertures.
Where the device is a brush it is preferred that the aperture is located centrally on the brush head. More preferably, the aperture is surrounded by bristles. Where there are more than one aperture they are preferably arranged symmetrically on the brush head to provide uniform release of nebulised.
Where the device is a comb it is preferred that there is a plurality of apertures located uniformly on the comb head.
Preferably, the nebuliser is located in a chamber in the device and the chamber is connected to the exterior by a channel.
Preferably, the device comprises a handle which houses the power source. Alternatively, the power source could be separate and the device powered through the mains.
Benefit agents can be selected from the group consisting of fragrances, silicone oils, waxes, hydrocarbons, higher fatty acids, essential oils, hair styling polymers, colourants, hair conditioners, hair cleansers, hair growth promoters, vitamins, hair straighteners, hair growth stimulants, hair growth retardants, hair shedding inhibitors, antibacterial compounds, antifungal compounds, anti-inflammatory compounds, anti-pruritic agents, sebum suppressants, sunscreens and mixtures thereof.
A particularly preferred benefit agent is silicone. Suitable silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone. Also particularly suitable for use compositions of the invention are polydimethyl siloxanes having hydroxyl end groups, which have the CTFA designation dimethiconol.
The viscosity of the emulsified silicone itself (not the emulsion or the final hair conditioning composition) is preferably at least 10,000 cSt (25° C.). The viscosity of the silicone itself is preferably at least 60,000 cSt (25° C.), most preferably at least 500,000 cSt (25° C.), ideally at least 900,000 cSt (25° C.). Preferably the viscosity does not exceed 3M cSt (25° C.).
Emulsified silicones for use the invention will typically have an average silicone particle size (D50) in the composition of less than 1000 nm, preferably less than 800 nm, more preferably less than 700 nm, ideally it ranges from 100 to 800 nm, more preferably from 150 nm to 600 nm.
Suitable silicone emulsions for use in compositions of the invention are available from suppliers of silicones such as Dow Corning and GE Silicones. The use of such pre-formed silicone emulsions is preferred for ease of processing and control of silicone particle size. Such pre-formed silicone emulsions will typically additionally comprise a suitable emulsifier such as an anionic or nonionic emulsifier, or mixture thereof, and may be prepared by a chemical emulsification process such as emulsion polymerisation, or by mechanical emulsification using a high shear mixer.
Examples of suitable pre-formed silicone emulsions include emulsions DC2-1766, DC-1785, DDC-1788, DC2-1865 and DC2-1870, all available from Dow Corning. These are all emulsions/microemulsions of dimethiconol. Preferred silicones are DC5-7051, particularly preferred are DC1788 and DC 1785.
Mixtures of any of the above described silicone emulsions may also be used.
The silicone level is preferably present at from 0.1 to 40% wt of the total composition, more preferably from 0.5 to 35% wt. especially from 1 to 30% wt. The level of silicone that can be deposited is dependent on the silicone used.
Compositions for use with the invention suitably comprises a carrier. Preferably, this carrier is water.
Preferably the levels of carrier in the total composition are above 60 wt % of the total composition, more preferably above 70 wt %, most preferably above 80 wt %.
The viscosity of the final composition is preferably from 1 cSt to 8 cSt at 25° C. a more preferably from 2 cSt to 7.5 cSt (25° C.), most preferably they have a viscosity above 3.5M cSt (25° C.). When nebulising a silicone emulsion it is found that more silicone can be deposited at higher composition viscosities than if a solution of silicone is used.
It is preferred if the products are left on hair after application and not immediately washed off (within 10 minutes of application). Such products are known as leave in compositions.
The pH of the formulation is preferably from 2.5 to 6 at 25° C. More preferably from 3 to 5.
Examples of suitable emulsifying agents include nonionic, cationic, anionic surfactants, or mixtures thereof. If such an emulsifying agent is used, it is preferably present at a level of from about 0.01% to about 7.5% by weight based on total weight of the composition.
The invention will now be described with reference to the following non-limiting drawings in which:
In detail
The following are non-limiting Examples according to the invention.
Approximately 1 g of each aqueous emulsion was nebulised into a sealed container of known weight. The water was evaporated from the container and the amount of silicone nebulised was measured by re-weighing the container.
The standard error of this experiment was calculated which is equivalent to the error in the deposited value which is 0.0014 g.
The results of this experiment express conclusively that there is no loss of silicone transport with emulsions of the invention.
DC5-7051 (2 wt % in water) and DC200 350cSt in isododecane were applied using a nebuliser to dry hair. 2.5 g TA switches which were laid flat. An X-ray fluorescence sample was taken from the centre of the switch and the level of silicone measured.
The above data shows that DC5-7051 emulsion at 2% exhibits better deposition (relative to expected value) than a solution of 0.5% DC200 in Isododecane.
| Number | Date | Country | Kind |
|---|---|---|---|
| 08166377.5 | Oct 2008 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP09/59942 | 7/31/2009 | WO | 00 | 4/7/2011 |
