Patent Application
20120245075
The following invention is directed to creating a high performance fragrance formulation.
In the early 1960's, Jean Carles developed a method to create fine fragrances by defining a fragrance as being made up of with ingredients designated as top, middle and base notes and with the fragrance formulation containing 25% top, 20% middle and 55% base notes (Series of publications in Reserches, 1961, 1962, 1963). Top notes are defined as volatile ingredients that lack tenacity on blotters or smelling strips and that provide strong performance at initial product application. Middle notes or “modifiers” have intermediate volatility and tenacity on blotters while the heavier base notes provide the long lasting component expected in every fragrance.
In practice, it is usually the case that many of the compounds considered “top” notes are fleeting, and disappear from the vapor around the wearer within the first five minutes of application. While these notes contribute a pleasurable moment for the user, they contribute little to the aroma that another observer would recognize as the signature consumers identify with of a particular fine fragrance. Therefore the aura the wearer projects over the first few hours is composed of compounds which are diffusive over time, and compounds which gradually decline in the vapor as the fragrance evolves. These compounds are distinguished in the present invention from the top and middle dichotomy, to simply one class known as ‘push’.
One important performance parameter for fine fragrances is their ability to be noticed and appreciated in the “air” around the fragrance user. This parameter is typically referred to as fragrance diffusivity. An added benefit for most fine fragrances is their ability to be diffusive over time and therefore continue to provide performance during a typical use cycle for the fragrance. A high performing fine fragrance will combine this continued diffusivity benefit along with being designed to meet different olfactive and hedonic characteristics.
In efforts to increase the long-lasting, diffusive performance of fragrance additives such as fixatives, pro-fragrances and delivery systems have been disclosed in U.S. Pat. No. 7,196,052, European Patent No. 0977548B2, and U.S. Pat. No. 7,119,057. While these additives have been reported to offer fragrance performance benefits, they also can have issues depending on the fragrances product application. These issues can include negative interactions with the product and/or fragrance, inefficient mode of activation on skin, negative product sensory aspects and others.
We have surprisingly found that we can create long-lasting, high performing fragrances by designing these fragrances with a specific range of and combination of “diffusive” ingredients as defined by a diffusivity index without the addition of fixatives, profragrances or delivery vehicles.
By systematically using appropriate amounts of high performing diffusive and push ingredients and using the remainder of the formula to provide further olfactive and hedonic characteristics, one can create a high performing, long lasting diffusive fragrance that is hedonically pleasing to the consumer.
In one embodiment of the invention, a method of formulating a high performance fragrance formulation by selecting an effective amount of long-lasting, diffusive fragrance ingredients selected from the group consisting of aroma chemicals and essential oils defined according to the following algorithm
wherein P is equal to molecular polarizability, V is equal to molecular volume, A is equal to the molecular surface area. Ψ is a constant falling within the range {0.0025-0.0055} and Δ is a constant falling in the range of {−0.55 to −1.0} and the pair result in the above equality. Compounds with a favorable push factor possess vapor pressures from about 0.1 to about 100 pa.
In another embodiment of the invention a method to formulate a high performance fragrance formulation is provided wherein at least 40 weight percent % of the formula by weight is comprised of fragrance ingredients where two constants (Ψ and Δ) can be found which are solutions to the equation and at least 5 weight percent % of formula by weight is comprised of compounds with a favorable push factor
In a further embodiment of the invention a method to formulate a high performance fragrance formulation is provided wherein about 50 weight percent % to about 90 weight percent % of all fragrance ingredients has constants (Ψ and Δ) which are a solution and about 5 to about 20 weight percent % of the fragrance ingredients have a favorable push factor.
In yet a further embodiment of the invention, a method to formulate a high performance fragrance formulation is provided wherein the weighted average of the constant Δ is above −0.5, more preferably the weighted average of the constant Δ is above −0.6.
According to the present invention, the effective diffusivity index was determined by correlating the long term effective performance of a compound applied on skin with the global molecular properties, specifically, molecular surface area, molecular volume, and polarizability/molar volume. The highly effective long lasting diffusive compounds are generally larger in size, with a relatively low surface area and high polarizability.
According to the present invention, molecular volume is defined as the molecular mass/molecular density. It is a measure of the volume occupied by a molecule (or scaled by moles, the volume occupied by a mole of molecules) condensed phase at room temperature and atmospheric pressure.
Molecular surface area is defined as the area of the Van der Waals surface area of a molecule. This is the area of an imaginary surface surrounding the molecule calculated where overlap between molecular orbitals of separate molecules in the condensed phase is of the lowest free energy.
Polarizability is defined as the capacity of a molecule to polarize in an electric field due to a displacement of mobile charges within the molecule. For a mole of molecules, these individual polarizabilities (p) sum to a molar polarizability (Np) value. Molecules with high polarizability tend to be unsaturated and sometimes aromatic and have functional groups which allow strong delocalization of electrons across pi systems between electron donor and acceptor pairs. These types of molecules tend to absorb strongly in the near UV and visible ranges.
Diffusivity is a time-space description of the transport of a property through a medium such as air. A highly desirable fragrance composition is one which can produce an experience not just at a point in time after application but over an extended period of several hours. This performance can be measured using purge and trap sampling techniques with subsequent GC and/or GC/MS analysis of the sample. This sampling technique allows fragrance concentrations to be quantified over the fragrance performance time-space continuum desired by consumers
The effective odor produced by the concert of compounds within a fragrance composition is described from a physical mode, and from a phenomenological mode.
As with any means to use physical or molecular properties of the fragrance composition, there are quantifiable uncertainties.
The structure of a compound has a profound effect on physical properties of the compound such as vapor pressure and water solubility, and on the neurobiological properties like odor character and odor threshold.
In one embodiment, the correlations of the global molecular and electronic properties with fragrance performance were explicitly established without appealing to secondary thermodynamic properties such as vapor pressure, water solubility, logP, Henry's law constant or boiling point.
Accordingly, the following algorithm has been developed to determine the proper combination of fragrance ingredients to create a high performance fragrance.
In one embodiment of the invention, a method of formulating a high performance fragrance formulation by selecting an effective amount of long-lasting, diffusive fragrance ingredients selected from the group consisting of aroma chemicals and essential oils defined according to the following algorithm:
wherein P is equal to molecular polarizability, V is equal to molecular volume; A is equal to the molecular surface area. Ψ is a constant falling within the range {0.0025-0.0055} and Δ is a constant falling in the range of {−0.55 to −1.0} and the pair result in the above equality. Compounds with a favorable push factor possess vapor pressures from about 0.1 to about 100 pa.
The mass or weight fractions of the compounds in the fragrance formula is designated by the algorithms to provide, in aggregate, those properties of a successful, highly performing benchmark fragrance that would be described as pleasantly diffusive.
One important performance parameter for fine fragrances is there ability to be noticed and appreciated in the “air” around the fragrance user. This parameter is typically referred to as fragrance diffusivity. An added benefit for most fine fragrances is their ability to be diffusive over time and therefore continue to provide performance during a typical use cycle for the fragrance. A high performing fine fragrance will combine this continued diffusivity benefit along with being designed to meet different olfactive/hedonic characteristics.
In another embodiment of the invention, a method to formulate a high performance fragrance formulation is provided wherein at least 40% of the formula by weight is comprised of fragrance ingredients where two constants (Ψ and Δ) can be found which are solutions to the equation and at least 5 weight percent % of formula by weight is comprised of compounds with a favorable push factor.
In a further embodiment of the invention a method to formulate a high performance fragrance formulation is provided wherein about 50 weight percent to about 90 weight percent % of all fragrance ingredients have constants (Ψ and Δ) which are a solution and about 5 weight percent to about 20 weight percent % of the fragrance ingredients have a favorable push factor.
In yet a further embodiment of the invention, a method to formulate a high performance fragrance formulation is provided wherein the weighted average of the constant Δ is above −0.5, more preferably the weighted average of the constant Δ is above −0.6.
To determine high performing diffusive ingredients, different fragrance formulas were prepared and tested for their performance. Analytical measurements were used to identify the fragrance ingredients present in higher performing fragrance formulas. The effectiveness of individual fragrance ingredients was determined by combining the analytical and olfactive assessments.
Understanding the chemical and physical properties of fragrance ingredients that contribute to the desired long-lasting and diffusive properties of a final fragrance creation provides insight into the design of hedonically pleasing and high performing perfumes.
Others have defined “enduring” fragrances as containing very high percentages of ingredients with high boiling points and high partition coefficients, but it has been found that by using more complex ingredient parameters, fragrance ingredients can be ranked in their effectiveness as long-lasting and diffusive. By combining these long-lasting diffusive ingredients with “push” ingredients, the performance of the fragrance can be optimized over the entire use cycle.
“Push” is defined by the ability of particular compounds to appear in the vapor around the wearer at a significantly higher level than the mean ingredient (from among approximately 1000 tested). These compounds are characterized by a high level in the vapor directly after application and a very gradual decline over a few hours.
Some preferred high performing diffusive fragrance ingredients include but are not limited by the following: galaxolide, iso gamma super, tonalid, hedione, cedrol, ambroxan, benzyl salicylate, eugenol, vertofix, ethylene brassylate, helional, hexyl cinnamaldehyde, amyl salicylate, polysantol, damascene delta and methyl ionone alpha.
These analytical and olfactive assessments also defined the “push” ingredients and they include, but are not limited by the following ingredients: aldehyde AA, aldehyde C10, fenchyl acetate, terpineol, styryl acetate, methyl nonyl ketone, linalool, dihydromyrcenol, menthol, linalyl acetate, benzyl acetate, allyl heptanoate, citronellol, citronellyl nitrile, isobutyl benzoate and citronellal.
Understanding fine fragrance performance over time is critical and as previously described, a perfume must be designed to provide benefits over the entire use cycle of the product. To that end, analytical measurements were obtained at different time points and an understanding of which ingredients contributed most to the fragrances performance at different time points was gleaned from these measurements.
All U.S. patents and patent applications cited herein are incorporated by reference as if set forth herein in their entirety.
The following are provided as specific embodiments of the present invention. Other modifications of this invention will be readily apparent to those skilled in the art. Such modifications are understood to be within the scope of this invention. As used herein all percentages are weight percent unless otherwise noted, ppm is understood to stand for parts per million, L is understood to be liter, mL is understood to be milliliter, pa is understood to be pascal, g is understood to be gram, mol is understood to be mole, and mmHg be millimeters (mm) of mercury (Hg). IFF as used in the examples is understood to mean International Flavors & Fragrances Inc., New York, N.Y., USA.
Below are examples of three compounds with a favorable diffusivity index (Df<−0.9), including calculations, and three compounds with unfavorable diffusivity indexes (Df>−0.9):
This example demonstrates two fragrances with very different performance. One fragrance was created to provide a weighted favorable long lasting, diffusive performance by providing a mixture containing >60 wt % diffusive ingredients (Fragrance 2) and the other fragrance will have poor long lasting performance as this mixture only contains −22 wt % diffusive ingredients. Measurements were made with TSAR Version 3 commercially available from Accelrys located in San Diego.
A sensory test was performed to show the difference in long, lasting diffusive performance of these two fragrances. In this test a total of four sprays (total ca. 0.42-0.43 g) is applied to four different areas of the wearer: one spray on each wrist and one on each side of the neck. Diffusivity evaluations were made at three time points: Initial impact, 4 hr & 8 hrs after product application. Each fragrance was applied to eight fragrance wearers and evaluated by eight judges trained in rating intensity of fragrances on labeled magnitude scale. The sensory judges evaluate the intensity of each fragrance from a distance of three feet while the fragrance wearers make ten passes walking briskly. Within each fragrance condition, the order in which the fragrance wearers walked past the judges is counterbalanced. Data analysis is performed by applying ANOVA to intensities of fragrances. Significance of the data is established at p<0.05.
This example demonstrates two fragrances with very different performance. One fragrance was created to provide a weighted favorable Σxi*Δi<−0.6, average delta value (WADf) (Fragrance 2) which will provide good long lasting, diffusive properties and one fragrance with weight averaged delta which will have limited performance Σxi*Δi>.−0.6. Measurements were made using TSAR Version 3 commercially available from Accelrys located in San Diego.
